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Office of Scientific and Technical Information
Wide-Bandgap Semiconductors
SciTech Connect
With the increase in demand for more efficient, higher-power, and higher-temperature operation of power converters, design engineers face the challenge of increasing the efficiency and power density of converters [1, 2]. Development in power semiconductors is vital for achieving the design goals set by the industry. Silicon (Si) power devices have reached their theoretical limits in terms of higher-temperature and higher-power operation by virtue of the physical properties of the material. To overcome these limitations, research has focused on wide-bandgap materials such as silicon carbide (SiC), gallium nitride (GaN), and diamond because of their superior material advantages such as large bandgap, high thermal conductivity, and high critical breakdown field strength. Diamond is the ultimate material for power devices because of its greater than tenfold improvement in electrical properties compared with silicon; however, it is more suited for higher-voltage (grid level) higher-power applications based on the intrinsic properties of the material [3]. GaN and SiC power devices have similar performance improvements over Si power devices. GaN performs only slightly better than SiC. Both SiC and GaN have processing issues that need to be resolved before they can seriously challenge Si power devices; however, SiC is at a more technically advanced stage than GaN. SiC is considered to be the best transition material for future power devices before high-power diamond device technology matures. Since SiC power devices have lower losses than Si devices, SiC-based power converters are more efficient. With the high-temperature operation capability of SiC, thermal management requirements are reduced; therefore, a smaller heat sink would be sufficient. In addition, since SiC power devices can be switched at higher frequencies, smaller passive components are required in power converters. Smaller heat sinks and passive components result in higher-power-density power converters. With the advent of the use of SiC devices it is imperative that models of these be made available in commercial simulators. This enables power electronic designers to simulate their designs for various test conditions prior to fabrication. To build an accurate transistor-level model of a power electronic system such as an inverter, the first step is to characterize the semiconductor devices that are present in the system. Suitable test beds need to be built for each device to precisely test the devices and obtain relevant data that can be used for modeling. This includes careful characterization of the parasitic elements so as to emulate the test setup as closely as possible in simulations. This report is arranged as follows: Chapter 2--The testing and characterization of several diodes and power switches is presented. Chapter 3--A 55-kW hybrid inverter (Si insulated gate bipolar transistor--SiC Schottky diodes) device models and test results are presented. A detailed description of the various test setups followed by the parameter extraction, modeling, and simulation study of the inverter performance is presented. Chapter 4--A 7.5-kW all-SiC inverter (SiC junction field effect transistors (JFET)--SiC Schottky diodes) was built and tested. The models built in Saber were validated using the test data and the models were used in system applications in the Saber simulator. The simulation results and a comparison of the data from the prototype tests are discussed in this chapter. Chapter 5--The duration test results of devices utilized in buck converters undergoing reliability testing are presented.
Chinthavali, M.S.
Wide Bandgap Semiconductors: Essential to Our Technology Future |
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
Wide Bandgap Semiconductors: Essential to Our Technology Future Wide Bandgap Semiconductors: Essential to Our Technology Future Wide Bandgap Semiconductors: Essential to Our Technology Future January 15, 2014 - 8:00am Addthis Learn how wide bandgap semiconductors could impact clean energy technology and our daily lives. | Video by Sarah Gerrity and Matty Greene, Energy Department. Dr. Ernest Moniz Dr. Ernest Moniz Secretary of Energy What are the key facts? North Carolina State University will lead the Energy Department's new manufacturing innovation institute for the next generation of power electronics, focusing on wide bandgap (WBG) semiconductors. Building America's leadership in WBG semiconductor manufacturing while driving down the cost of the technology could lead to more affordable products for businesses and consumers, billions of dollars in energy
Wide-Bandgap Compound Semiconductors to Enable Novel Semiconductor Devices
DOE Green Energy (OSTI)
This report represents the completion of a three-year Laboratory-Directed Research and Development (LDRD) program that focused on research and development of GaN-based wide bandgap semiconductor materials (referred to as III-N materials). Our theoretical investigations include the determination of fundamental materials parameters from first-principles calculations, the study of gain properties of III-N heterostructures using a microscopic laser theory and density-functional-theory, charge-state calculations to determine the core structure and energy levels of dislocations in III-N materials. Our experimental investigations include time-resolved photoluminescence and magneto-luminescence studies of GaN epilayers and multiquantum well samples as well as x-ray diffraction studies of AlGaN ternary alloys. In addition, we performed a number of experiments to determine how various materials processing steps affect both the optical and electrical properties of GaN-based materials. These studies include photoluminescence studies of GaN epilayers after post-growth rapid thermal annealing, ion implantation to produce n- and p-type material and electrical and optical studies of plasma-etched structures.
Crawford, M.H.; Chow, W.W.; Wright, A.F.; Lee, S.R.; Jones, E.D.; Han, J.; Shul, R.J.
Wide Bandgap Semiconductors: Pursuing the Promise
NLE Websites -- All DOE Office Websites (Extended Search)
the size of an automotive cooling system by 60% or even eliminate the secondary liquid cooling system. 2 Military: WBG semiconductors have great potential as an enabling...
Anomalous Charge Transport in Disordered Organic Semiconductors
Science Conference Proceedings (OSTI)
Anomalous charge carrier transport in disordered organic semiconductors is studied using fractional differential equations. The connection between index of fractional derivative and dispersion exponent is examined from the perspective of fractional Fokker-Planck equation and its link to the continuous time random walk formalism. The fractional model is used to describe the bi-scaling power-laws observed in the time-of flight photo-current transient data for two different types of organic semiconductors.
Muniandy, S. V.; Woon, K. L. [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Choo, K. Y. [Faculty of Engineering, Multimedia University, 63100 Cyberjaya, Selangor (Malaysia)
Method of depositing wide bandgap amorphous semiconductor materials
DOE Patents (OSTI)
A method of depositing wide bandgap p type amorphous semiconductor materials on a substrate without photosensitization by the decomposition of one or more higher order gaseous silanes in the presence of a p-type catalytic dopant at a temperature of about 200.degree. C. and a pressure in the range from about 1-50 Torr.
Ellis, Jr., Frank B. (Princeton Junction, NJ); Delahoy, Alan E. (Rocky Hill, NJ)
Wide Bandgap Semiconductors for Clean Energy Workshop: Summary...
Facilitator: Foundry service is from Defense Advanced Research Projects Agency (DARPA), Metal Oxide Semiconductor Implementation Service (MOSIS). There is an evaluation of...
High-Throughput Transfer Imprinting for Organic Semiconductors
E-Print Network (OSTI)
Development of nanoimprint lithography(NIL) has enabled high-throughput and high-resolution patterning over the optical limitation. In recent years, thermal nanoimprint has been used to directly pattern functional materials such as organic semiconductors because heat and pressure used in thermal nanoimprint do not damage functional materials. However, issues such as residual layer removal and mold contamination still limit the application of nanoimprint for organic semiconductor patterning. In this work, nanoimprint-based transfer imprinting of organic semiconductor is studied. In the same time the suggested technique is simulated with COMSOL multi-physics simulator to understand its mechanism. This transfer printing technique utilize thermal nanoimprint scheme to enable residual-layer-free patterning of organic semiconductors without mold contamination. The transfer imprinting technique is amenable to roll-to-roll process for high-throughput patterning of organic semiconductors for low-cost organic electronic applications.
Choo, Gihoon
Bottoms Up: Better Organic Semiconductors for Printable ...
... A patent from British researchers in 2005 offered a promising compromise: blend the small semiconductor molecules in with the polymer. ...
Electroluminescence in ion gel gated organic polymer semiconductor transistors
emission in ion gel gated, thin film organic semiconductor tran- sistors and investigates the light emission mechanism behind these devices. We report that ion gel gated organic polymer semiconductor transistors emit light when the drain source volt- age... the organic light emitting devices become mainstream, there are several challenges that need to be resolved and current research focus is to ad- dress those challenges. One particular challenge is relatively high operating volt- ages of light emitting organic...
Bhat, Shrivalli
Method and apparatus for use of III-nitride wide bandgap semiconductors in optical communications
The present disclosure relates to the use of III-nitride wide bandgap semiconductor materials for optical communications. In one embodiment, an optical device includes an optical waveguide device fabricated using a III-nitride semiconductor material. The III-nitride semiconductor material provides for an electrically controllable refractive index. The optical waveguide device provides for high speed optical communications in an infrared wavelength region. In one embodiment, an optical amplifier is provided using optical coatings at the facet ends of a waveguide formed of erbium-doped III-nitride semiconductor materials.
Hui, Rongqing (Lenexa, KS); Jiang,Hong-Xing (Manhattan, KS); Lin, Jing-Yu (Manhattan, KS)
Organic conductive films for semiconductor electrodes
According to the present invention, improved electrodes overcoated with conductive polymer films and preselected catalysts are provided. The electrodes typically comprise an inorganic semiconductor overcoated with a charge conductive polymer film comprising a charge conductive polymer in or on which is a catalyst or charge-relaying agent.
Frank, Arthur J. (Lakewood, CO)
Photocell utilizing a wide-bandgap semiconductor material
A photocell comprises a p-i-n amorphous silicon structure having a wide bandgap layer adjacent to either the p-type or n-type layer. This structure reduces the absorption of light entering the photocell and the back-diffusion of minority carriers.
Carlson, David E. (Yardley, PA); Williams, Brown F. (Princeton, NJ)
Toward a Unified Treatment of Electronic Processes in Organic Semiconductors
A quantitative study of n-type doping in highly crystalline organic semiconductor films establishes the predominant influence of electrostatic forces in these low-dielectric materials. Based on these findings, a self-consistent model of doped (purposely or not) organic semiconductors is proposed in which: (1) the equilibrium free carrier density, nf, is a small fraction of the total charge density; (2) a superlinear increase in conductivity with doping density is universal; (3) nf increases with applied electric field; and (4) the carrier mobility is field-dependent regardless of crystallinity.
Gregg. B.A.
Hyperfine interaction and magnetoresistance in organic semiconductors
We explore the possibility that hyperfine interaction causes the recently discovered organic magnetoresistance (OMAR) effect. Our study employs both experiment and theoretical modelling. An excitonic pair mechanism model based on hyperfine interaction, previously suggested by others to explain magnetic field effects in organics, is examined. Whereas this model can explain a few key aspects of the experimental data, we, however, uncover several fundamental contradictions as well. By varying the injection efficiency for minority carriers in the devices, we show experimentally that OMAR is only weakly dependent on the ratio between excitons formed and carriers injected, likely excluding any excitonic effect as the origin of OMAR.
Y. Sheng; D. T. Nguyen; G. Veeraraghavan; �. Mermer; M. Wohlgenannt; U. Scherf
Development of New Building Blocks for Constructing Novel Polymer Semiconductors for Organic Thin Film Transistors.
??Organic semiconductors are envisioned to have widespread applications in flexible displays, radio-frequency identification (RFID) tags, bio- and chem-sensors, as well as organic solar cells. Polymer� (more)
Yan, Zhuangqing
ESS 2012 Peer Review - Engineered Gate Oxides for Wide Bandgap Semiconductor MOSFETs - Jon Ihlefeld, SNL
-5 -5 10 -4 10 -3 10 -2 10 -1 10 0 10 1 -6 -4 -2 0 2 4 6 8 10 |J Leakage | (A-cm -2 ) Semiconductor Voltage (V) Engineered Gate Oxides for Wide Bandgap S emiconductor M OSFETs* Jon I hlefeld, M ichael B rumbach, S andeepan D asGupta, and Stanley AtciEy Sandia NaGonal Laboratories *Sponsored b y t he U .S. D epartment o f E nergy's O ffice o f E lectricity E nergy S torage Systems P rogram email@example.com, 505---844---3162; s firstname.lastname@example.com, 505---284---2701 Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND No. 2011-XXXXP Cooling Power electronics Energy storage Energy storage -V gate Low defect oxide Metal gate Wide
Electronic Properties of Disordered Organic Semiconductors via QM/MM Simulations
Organic semiconductors (OSCs) have recently received significant attention for their potential use in photovoltaic, light emitting diode, and field effect transistor devices. Part of the appeal of OSCs is the disordered, ...
Difley, Seth
Laboratory Thin-Film Encapsulation of Air-Sensitive Organic Semiconductor Devices
We present an approach, which is compatible with both glass and polymer substrates, to in-laboratory handling and intra-laboratory shipping of air-sensitive organic semiconductors. Encapsulation approaches are presented ...
Subbarao, Samuel P.
Physics and simulation of transport processes in hybrid organic semiconductor devices
Organic semiconductors and nanomaterials promise to potentially form the basis for future efficient and cost-effective large area optoelectronic devices, such as lightemitting diodes and solar cells. Although these materials' ...
Rousseau, Ian Michael
Photocatalytic Oxidation of Aqueous Organic Contaminants by Semiconductors using Visible Light Radiation
· Continuously mixed Light Source · T5 8 watt florescent bulbs · "Daylight Spectrum" · Color Rendering Index 75Photocatalytic Oxidation of Aqueous Organic Contaminants by Semiconductors using Visible Light
Meyers, Steven D.
Singlet exciton fission, a multi-exciton generation process, in organic semiconductor solar cells
Organic semiconductor photovoltaics hold the promise of cheap production and low manufacturing setup costs. The highest efficiency seen in research labs, ~10% today, is still too low for production. In this work we explore ...
Jadhav, Priyadarshani
Spectroscopy of Charge Carriers and Traps in Field-Doped Organic Semiconductors
This research project aims to achieve quantitative and molecular level understanding of charge carriers and traps in field-doped organic semiconductors via in situ optical absorption spectroscopy, in conjunction with time-resolved electrical measurements. During the funding period, we have made major progress in three general areas: (1) probed charge injection at the interface between a polymeric semiconductor and a polymer electrolyte dielectric and developed a thermodynamic model to quantitatively describe the transition from electrostatic to electrochemical doping; (2) developed vibrational Stark effect to probe electric field at buried organic semiconductor interfaces; (3) used displacement current measurement (DCM) to study charge transport at organic/dielectric interfaces and charge injection at metal/organic interfaces.
Zhu, Xiaoyang; Frisbie, C Daniel
From semiconductor-semiconductor transition (42 K) to the highest- Tc organic superconductor,. kappa. -(ET) sub 2 Cu(N(CN) sub 2 )Cl ( Tc = 12. 5 K)
The discovery of an organic superconductor with the highest transition temperature (125 K) recorded following the suppression of a semiconductor-semiconductor transition (42 K) is reported. The reported compound is a kappa-phase superconductor, kappa-(ET){sub 2}Cu(N(CN){sub 2})Cl, which is isostructural with the recently prepared ambient-pressure superconductor kappa-(ET){sub 2}Cu(N(CN){sub 2})Br with a transition temperature of 11.5 K that has been previously reported. Band electronic structural calculations show the newly discovered compound to be a two-dimensional metal. 15 refs., 2 figs.
Williams, J.M.; Kini, A.M.; Wang, H.H.; Carlson, K.D.; Geiser, U.; Montgomery, L.K.; Pyrka, G.J.; Watkins, D.M.; Kommers, J.M.; Boryschuk, S.J.; Strieby Crouch, A.V.; Kwok, W.K. (Argonne National Lab., IL (USA)); Schirber, J.E.; Overmyer, D.L. (Sandia National Labs., Albuquerque, NM (USA)); Jung, D.; Whangbo, Myunghwan (North Carolina State Univ., Raleigh (USA))
Optical and electrical properties of III-V nitride wide bandgap semiconductors. Annual report, April 1, 1997--May 31, 1998
The objectives of this project were to investigate the optical and electrical properties of III-nitride wide bandgap semiconductors (GaN, InGaN, AlGaN) and quantum wells, to understand the fundamental optical transitions and impurity properties of these materials, to study the physics components of GaN-based devices, and to provide input for new approaches toward the improvement of materials quality and the optimization of device design. We were the first group to employ transport measurement techniques on the persistent photoconductivity (PPC) state to study the impurity properties of III-nitrides. We were also one of the few research groups m in the world to employ picosecond time-resolved photoluminescence (PL) measurement technique to study mechanisms of optical transitions, LED emission, and lasing m in GaN materials. During this funding period, we have investigated a variety of GaN samples and structures grown by MBE as well as by MOCVD. We have also made a significant progress in MOCVD GaN materials growth. This report briefly discusses the following accomplishments: effects of deep level impurities in the AlGaN/GaN heterostructures; materials characterization of III-nitrides alloys; optical studies of III-nitride epilayers and quantum wells; fabrication and optical studies of III-nitride microdisk arrays; and materials growth by MOCVD.
Negative capacitance in organic semiconductor devices: bipolar injection and charge recombination mechanism
We report negative capacitance at low frequencies in organic semiconductor based diodes and show that it appears only under bipolar injection conditions. We account quantitatively for this phenomenon by the recombination current due to electron-hole annihilation. Simple addition of the recombination current to the well established model of space charge limited current in the presence of traps, yields excellent fits to the experimentally measured admittance data. The dependence of the extracted characteristic recombination time on the bias voltage is indicative of a recombination process which is mediated by localized traps.
Ehrenfreund, E; Dennler, G; Neugebauer, H; Sariciftci, N S
Development of nanostructured and surface modified semiconductors for hybrid organic-inorganic solar cells.
Solar energy conversion is increasingly being recognized as one of the principal ways to meet future energy needs without causing detrimental environmental impact. Hybrid organic-inorganic solar cells (SCs) are attracting particular interest due to the potential for low cost manufacturing and for use in new applications, such as consumer electronics, architectural integration and light-weight sensors. Key materials advantages of these next generation SCs over conventional semiconductor SCs are in design opportunities--since the different functions of the SCs are carried out by different materials, there are greater materials choices for producing optimized structures. In this project, we explore the hybrid organic-inorganic solar cell system that consists of oxide, primarily ZnO, nanostructures as the electron transporter and poly-(3-hexylthiophene) (P3HT) as the light-absorber and hole transporter. It builds on our capabilities in the solution synthesis of nanostructured semiconducting oxide arrays to this photovoltaic (PV) technology. The three challenges in this hybrid material system for solar applications are (1) achieving inorganic nanostructures with critical spacing that matches the exciton diffusion in the polymer, {approx} 10 nm, (2) infiltrating the polymer completely into the dense nanostructure arrays, and (3) optimizing the interfacial properties to facilitate efficient charge transfer. We have gained an understanding and control over growing oriented ZnO nanorods with sub-50 nm diameters and the required rod-to-rod spacing on various substrates. We have developed novel approaches to infiltrate commercially available P3HT in the narrow spacing between ZnO nanorods. Also, we have begun to explore ways to modify the interfacial properties. In addition, we have established device fabrication and testing capabilities at Sandia for prototype devices. Moreover, the control synthesis of ZnO nanorod arrays lead to the development of an efficient anti-reflection coating for multicrystalline Si solar cells. An important component of this project is the collaboration with Dr. Dave Ginley's group at NREL. The NREL efforts, which are funded by NREL's LDRD program, focus on measuring device performance, external quantum efficiency, photoconductance through highly specialized non-contact time-resolved microwave conductivity (TRMC) measurements, and vapor phase deposition of oxide materials. The close collaboration with NREL enables us to enter this competitive field in such short time. Joint publications and presentations have resulted from this fruitful collaboration. To this date, 5 referred journal papers have resulted from this project, with 2 more in preparation. Several invited talks and numerous contributed presentations in international conferences are also noted. Sandia has gained the reputation of being one of forefront research groups on nanostructured hybrid solar cells.
Hsu, Julia, W. P.
Rational Design and Preparation of Organic Semiconductors for use in Field Effect Transistors and Photovoltaic Cells
in thin film organic photovoltaic cells (OPVs) is presented.Effect Transistors and Photovoltaic Cells By Clayton EdwardEffect Transistors and Photovoltaic Cells By Clayton Edward
Mauldin, Clayton Edward
The meeting shall strive to develop and further the fundamental understanding of defects and their roles in the structural, electronic, optical, and magnetic properties of bulk, thin film, and nanoscale semiconductors and device structures. Point and extended defects will be addressed in a broad range of electronic materials of particular current interest, including wide bandgap semiconductors, metal-oxides, carbon-based semiconductors (e.g., diamond, graphene, etc.), organic semiconductors, photovoltaic/solar cell materials, and others of similar interest. This interest includes novel defect detection/imaging techniques and advanced defect computational methods.
Doping in Organic Semiconductors: Impact of Trap Filling on Interface Control and Charge Carrier Mobility
2 /V.s. Numerical simulations utilizing kinetic Monte Carlo method confirm an exponential tail, chemical, structural and electrical properties of materials relevant to thin-film electronic devices. His developed for applications in organic and molecular electronics. His group is particularly interested
Ejiri, Shinji
Data mining solves tough semiconductor manufacturing problems
Keywords: data mining, machine learning, manufacturing optimization, neural networks, pattern recognition, rule induction, self organizing maps, semiconductor yield enhancement
Mike Gardner; Jack Bieker
Semiconductors News
... Nhan Nguyen demonstrates how he performs optical measurements on a graphene-insulator-semiconductor sample structure. ...
The synthesis of inorganic semiconductor nanocrystalline materials for the purpose of creating hybrid organic/inorganic light-emitting devices
Colloidal semiconductor nanocrystals (NCs) or quantum dots (QDs) can be synthesized to efficiently emit light from the ultraviolet, across the entire visible spectrum, and into the near infrared. This is now possible due ...
Steckel, Jonathan S. (Jonathan Stephen)
Raman scattering in organic semiconductors based on erbium biphthalocyanine molecules and chlorine-containing europium-lutetium triphthalocyanine molecules
The Raman spectra of semiconductor structures based on erbium biphthalocyanine molecules and chlorine-substituted europium-lutetium triphthalocyanine molecules are studied on excitation with Ar{sup +} laser radiation at the wavelength 514 nm. The data on the spectral position of Raman intensity peaks related to vibronic states of the basic molecular groups forming the semiconductor are obtained. Raman lines irrelevant to the known vibronic states of the basic phthalocyanine molecular groups are observed in the ranges 100-500 and 500-900 cm{sup -1}. It is shown that, in the spectra of triphthalocyanine, some lines are structurally complex and shifted with respect to the characteristic lines of molecular groups by several inverse centimeters.
Belogorokhov, I. A., E-mail: email@example.com [Federal State Research and Design Institute for Rare-Metal Industry (Russian Federation); Mamichev, D. A.; Dronov, M. A.; Pushkarev, V. E.; Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)
Semiconductor Analytics
... LED Lighting and Displays � Solar PV � Why Semiconductors? ... Potential Comments Solar PV 20.4 25-30% Politically driven. BP disaster will help. ...
Vibronic states in organic semiconductors based on non-metal naphthalocyanine. Detection of heterocyclic phthalocyanine compounds in a flexible dielectric matrix
The vibronic properties of semiconductor structures based on non-metal naphthalocyanine molecules are studied using IR and Raman spectroscopy methods. New absorption lines in the transmission spectra of such materials are detected and identified. Three transmission lines are observed in the range 2830-3028 cm{sup -1}, which characterize carbon-hydrogen bonds of peripheral molecular groups. Their spectral positions are 2959, 2906, and 2866 cm{sup -1}. It is detected that the phthalocyanine ring can also exhibit its specific vibronic properties in the Raman spectra at 767, 717, and 679 cm{sup -1}. The naphthalocyanine molecule in the organic dielectric matrix of microfibers is described using IR spectroscopy. It is shown that the set of vibrations characterizing the isoindol group, pyrrole ring, naphtha group, and C-H bonds, allows an accurate enough description of the vibronic states of the naphthalocyanine complex in complex heterostructures to be made. The spectral range with fundamental modes, characterizing a naphthalocyanine semiconductor in a heterostructure, is 600-1600 cm{sup -1}. A comparison of the compositions of complex systems with a similar heterostructure containing lutetium diphthalocyanine demonstrated few errors.
Belogorokhov, I. A., E-mail: firstname.lastname@example.com [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Tikhonov, E. V. [Moscow State University (Russian Federation); Dronov, M. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Belogorokhova, L. I. [Moscow State University (Russian Federation); Ryabchikov, Yu. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)
The Yeast Proteome Database (YPD): a model for the organization of genome-wide functional data. Nucleic Acids Res
The Yeast Proteome Database (YPD) is a model for the organization and presentation of comprehensive protein information. Based on the detailed curation of the scientific literature for the yeast Saccharomyces cerevisiae, YPD contains more than 50 000 annotations lines derived from the review of 8500 research publications. The information concerning each of the ?6100 yeast proteins is structured around a convenient one-page format, the Yeast Protein Report, with additional information provided as pop-up windows. Protein classification schema have been revised this year, defining each protein�s cellular role, function and pathway, and adding a Functional Abstract to the Yeast Protein Report. These changes provide the user with a succinct summary of the protein�s function and its place in the biology of the cell, and they enhance the power of YPD Search functions. Precalculated sequence alignments have been added, to provide a crossover point for comparative genomics. The first transcript profiling data has been integrated into the YPD Protein Reports, providing the framework for the presentation of genome-wide functional data. The Yeast Proteome Database can be accessed on the Web at
Peter E. Hodges; Andrew H. Z. Mckee; Brian P. Davis; William E. Payne; James I. Garrels
Improved Organic Photovoltaics - Energy Innovation Portal
Solar Photovoltaic Improved Organic Photovoltaics B4 Materials For Organic Semiconductor Applications, Including Molecular Electronics And Organic Photovoltaics
Wide Bandgap Semiconductor Material Growth and Characterization
Mar 6, 2013 ... Advanced Materials for Power Electronics, Power Conditioning, and Power .... due to a historical lack of native substrates and challenges in selectively ... have been optimized to provide equal growth rates of both polarities.
... Motors: WBG materials will enable higher-efficiency, variable- speed drives in motors�pumps, fans, compressors, and HVAC systems�used ...
... Geothermal: WBG-based electronic sensors can withstand the harsh, high-pressure, and high-temperature environments of geothermal wells. ...
Wide Bandgap Semiconductors Materials Growth and ...
Progress in 4H SiC Wafers and Epitaxy for Power Electronics Applications: Darren Hansen1; Mark Loboda1; Stephan Mueller1; Jie Zhang1; Bernd Thomas1
Stretchable semiconductor elements and stretchable electrical circuits
The invention provides methods and devices for fabricating printable semiconductor elements and assembling printable semiconductor elements onto substrate surfaces. Methods, devices and device components of the present invention are capable of generating a wide range of flexible electronic and optoelectronic devices and arrays of devices on substrates comprising polymeric materials. The present invention also provides stretchable semiconductor structures and stretchable electronic devices capable of good performance in stretched configurations.
Rogers, John A. (Champaign, IL); Khang, Dahl-Young (Seoul, KR); Menard, Etienne (Durham, NC)
Genome-wide SNP discovery in walnut with an AGSNP pipeline updated for SNP discovery in allogamous organisms
in walnut with an AGSNP pipeline updated for SNP discoveryin walnut with an AGSNP pipeline updated for SNP discoverythe development of a pipeline (AGSNP) for genome-wide SNP
II-V Compound Semiconductors - Microsystems Science, Technology...
researched, developed and delivered include: A wide variety of specialty semiconductor lasers Integrated VCSEL-RCPD circuits (vertical-cavity surface-emitting lasers,...
Sandia National Labs: PCNSC: Departments: Semiconductor and Optical
Semiconductor & Optical Sciences Semiconductor & Optical Sciences > Semiconductor Material & Device Sciences > Advanced Materials Sciences > Lasers, Optics & Remote Sensing Energy Sciences Small Science Cluster Business Office News Partnering Research Jeff Nelson Jerry A. Simmons Sr. Manager Idabelle Idabelle Courtney Admin. Asst. Departments Semiconductor and Optical Sciences The Semiconductor and Optical Sciences Department oversees the operations of the following departments providing new scientific knowledge that can lead to technology solutions in the areas of: Compound semiconductor optoelectronic materials and devices Chemical science to materials technologies, emphasizing the science and engineering of Metal Organic Chemical Vapor Deposition (MOCVD) Remote sensing and detection of WMD proliferation activities
Wafer-fused semiconductor radiation detector
Wafer-fused semiconductor radiation detector useful for gamma-ray and x-ray spectrometers and imaging systems. The detector is fabricated using wafer fusion to insert an electrically conductive grid, typically comprising a metal, between two solid semiconductor pieces, one having a cathode (negative electrode) and the other having an anode (positive electrode). The wafer fused semiconductor radiation detector functions like the commonly used Frisch grid radiation detector, in which an electrically conductive grid is inserted in high vacuum between the cathode and the anode. The wafer-fused semiconductor radiation detector can be fabricated using the same or two different semiconductor materials of different sizes and of the same or different thicknesses; and it may utilize a wide range of metals, or other electrically conducting materials, to form the grid, to optimize the detector performance, without being constrained by structural dissimilarity of the individual parts. The wafer-fused detector is basically formed, for example, by etching spaced grooves across one end of one of two pieces of semiconductor materials, partially filling the grooves with a selected electrical conductor which forms a grid electrode, and then fusing the grooved end of the one semiconductor piece to an end of the other semiconductor piece with a cathode and an anode being formed on opposite ends of the semiconductor pieces.
Lee, Edwin Y. (Livermore, CA); James, Ralph B. (Livermore, CA)
Wide Bandgap Extrinsic Photoconductive Switches
Photoconductive semiconductor switches (PCSS) have been investigated since the late 1970s. Some devices have been developed that withstand tens of kilovolts and others that switch hundreds of amperes. However, no single device has been developed that can reliably withstand both high voltage and switch high current. Yet, photoconductive switches still hold the promise of reliable high voltage and high current operation with subnanosecond risetimes. Particularly since good quality, bulk, single crystal, wide bandgap semiconductor materials have recently become available. In this chapter we will review the basic operation of PCSS devices, status of PCSS devices and properties of the wide bandgap semiconductors 4H-SiC, 6H-SiC and 2H-GaN.
Sullivan, J S
Improved Organic Semiconductors and Organic Vaccine for ...
Helical Nanofilament Phases. Science. 2009 Jul 24; 456-460. PDF available upon request. Author: polak Created Date: 10/17/2013 1:05:17 PM ...
The drawback to using these typical inorganic photovoltaic ... is that processing is often quite expensive and energy ... which has potential for use ...
Details in Semiconductors Gordon Conference, New London, NH, August 3-8, 2008
Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in homogeneous and structured semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, with an increases emphasis on nanostructures as compared to previous conferences. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference deals with defects in a broad range of bulk and nanoscale electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, doped nanoparticles, and organic semiconductors. Presentations of state-of-the-art theoretical methods will contribute to a fundamental understanding of atomic-scale phenomena. The program consists of about twenty invited talks, with plenty of discussion time, and a number of contributed poster sessions. Because of the large amount of discussion time, the conference provides an ideal forum for dealing with topics that are new and/or controversial.
Shengbai Zhang and Nancy Ryan Gray
Process for forming shaped group II-VI semiconductor nanocrystals, and product formed using process
A process for the formation of shaped Group II-VI semiconductor nanocrystals comprises contacting the semiconductor nanocrystal precursors with a liquid media comprising a binary mixture of phosphorus-containing organic surfactants capable of promoting the growth of either spherical semiconductor nanocrystals or rod-like semiconductor nanocrystals, whereby the shape of the semiconductor nanocrystals formed in said binary mixture of surfactants is controlled by adjusting the ratio of the surfactants in the binary mixture.
Alivisatos, A. Paul (Oakland, CA); Peng, Xiaogang (Fayetteville, AR); Manna, Liberato (Palo del Colle, IT)
Process for forming shaped group III-V semiconductor nanocrystals, and product formed using process
A process for the formation of shaped Group III-V semiconductor nanocrystals comprises contacting the semiconductor nanocrystal precursors with a liquid media comprising a binary mixture of phosphorus-containing organic surfactants capable of promoting the growth of either spherical semiconductor nanocrystals or rod-like semiconductor nanocrystals, whereby the shape of the semiconductor nanocrystals formed in said binary mixture of surfactants is controlled by adjusting the ratio of the surfactants in the binary mixture.
2010 Defects in Semiconductors GRC
Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.
Shengbai Zhang
Methods and devices for fabricating and assembling printable semiconductor elements
Nuzzo, Ralph G; Rogers, John A; Menard, Etienne; Lee, Keon Jae; Khang, Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao
Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Durham, NC); Lee, Keon Jae (Daejeon, KR); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Champaign, IL); Meitl, Matthew (Raleigh, NC); Zhu, Zhengtao (Urbana, IL)
Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Urbana, IL); Lee, Keon Jae (Savoy, IL); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Champaign, IL); Meitl, Matthew (Champaign, IL); Zhu, Zhengtao (Urbana, IL)
Photoelectrosynthesis at semiconductor electrodes
The general principles of photoelectrochemistry and photoelectrosynthesis are reviewed and some new developments in photoelectrosynthesis are discussed. Topics include energetics of semiconductor-electrolyte interfaces(band-edge unpinning); hot carrier injection at illuminated semiconductor-electrolyte junctions; derivatized semiconductor electrodes; particulate photoelectrochemical systems; layered compounds and other new materials; and dye sensitization. (WHK)
Nozik, A. J.
Spire Semiconductor formerly Bandwidth Semiconductor LLC | Open Energy
Open Energy Info (EERE)
Semiconductor formerly Bandwidth Semiconductor LLC Semiconductor formerly Bandwidth Semiconductor LLC Jump to: navigation, search Name Spire Semiconductor (formerly Bandwidth Semiconductor LLC) Place Hudson, New Hampshire Zip 3051 Product Spire-owned US-based manufacturer of gallium-arsenide (GaAs) cells; offers design and manufacturing capabilities of concentrator cells. References Spire Semiconductor (formerly Bandwidth Semiconductor LLC)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Spire Semiconductor (formerly Bandwidth Semiconductor LLC) is a company located in Hudson, New Hampshire . References ↑ "Spire Semiconductor (formerly Bandwidth Semiconductor LLC)" Retrieved from "http://en.openei.org/w/index.php?title=Spire_Semiconductor_formerly_Bandwidth_Semiconductor_LLC&oldid=351621"
Unitary lens semiconductor device
A unitary lens semiconductor device and method. The unitary lens semiconductor device is provided with at least one semiconductor layer having a composition varying in the growth direction for unitarily forming one or more lenses in the semiconductor layer. Unitary lens semiconductor devices may be formed as light-processing devices such as microlenses, and as light-active devices such as light-emitting diodes, photodetectors, resonant-cavity light-emitting diodes, vertical-cavity surface-emitting lasers, and resonant cavity photodetectors.
Lear, Kevin L. (Albuquerque, NM)
Study of the transport properties of organic semiconductors based on europium diphthalocyanine and bi-tris-phthalocyanine complexes with ortho-bis(oxymethyl)phenyl bridge and based on erbium and europium dinaphthalocyanine complexes
The transport properties of organic semiconductors based on europium diphthalocyanine and bitris-phthalocyanine complexes with ortho-bis(oxymethyl)phenyl bridge and based on europium and erbium dinaphthalocyanine are studied. The temperature dependences of the dc conductivity for all types of the structures under study are obtained; it is shown that all dependences include two activation portions. For high-temperature portions, the activation energies are determined as 0.85 eV for europium diphthalocyanine with the ortho-bis(oxymethyl)phenyl bridge, 1.135 eV for europium bi-tris-phthalocyanine with the orthobis(oxymethyl)phenyl bridge, 0.98 eV for europium dinaphthalocyanine, and 1.18 eV for erbium dinaphthalocyanine. For the low-temperature activation portion, it is shown that lanthanide ions and their bond with a ligand make the dominant contribution to the conductivity of the structures under study.
Belogorokhov, I. A., E-mail: firstname.lastname@example.com [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Tikhonov, E. V. [Moscow State University (Russian Federation); Dronov, M. A. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Ryabchikov, Yu. V. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Pashkova, N. V.; Kladova, E. I. [State Research and Project Institute of Rare-Metal Industry GIREDMET (Russian Federation); Belogorokhova, L. I.; Tomilova, L. G.; Khokhlov, D. R. [Moscow State University (Russian Federation)
Uranium Oxide Semiconductors
of semiconductors, it would consume the annual production rate of depleted uranium from uranium enrichment facilities. For more information: PDF Semiconductive Properties of...
Theory of Semiconductor Laser Cooling .
??Recently laser cooling of semiconductors has received renewed attention, with the hope that a semiconductor cooler might be able to achieve cryogenic temperatures. In order� (more)
Rupper, Greg
Exploring and enhancing conductivity in semiconductor nanoparticle films
Semiconductor nanocrystals (NCs) are a promising material for use in opto-electronic devices as their optical properties tune with particle size. NCs formed via colloidal synthesis are suspended in solution by the organic ...
Porter, Venda Jane
Atomic hydrogen cleaning of semiconductor photocathodes
Negative Electron Affinity (NEA) semiconductor photocathodes are widely used for the production of polarized electron beams, and are also useful for the production of high brightness electron beams which can be modulated at very high frequencies. Preparation of an atomically clean semiconductor surface is an essential step in the fabrication of a NEA photocathode. This cleaning step is difficult for certain semiconductors, such as the very thin materials which produce the highest beam polarization, and those which have tightly bound oxides and carbides. Using a small RF dissociation atomic hydrogen source, the authors have reproducibly cleaned GaAs wafers which have been only degreased prior to installation in vacuum. They have consistently prepared very high quantum efficiency photocathodes following atomic hydrogen cleaning. Details of their apparatus and most recent results are presented.
Sinclair, C.K.; Poelker, B.M.; Price, J.S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
Ferromagnetism in Oxide Semiconductors
In order to become a practical technology, semiconductor spintronics requires the discovery and utilization of ferromagnetic semiconductors which exhibit spin polarization in the majority carrier band at and above room temperature. Intrinsic remanent magnetization would allow spin polarized currents to be propagated in such materials without the need for a continuous magnetic field. However, the discovery and understanding of such materials is proving to be a grand challenge in solid-state science. Indeed, one of the 125 critical unanswered scientific questions recently posed in Science magazine asks, �Is it possible to create magnetic semiconductors that work at room temperature?�
Chambers, Scott A.; Droubay, Timothy; Wang, Chong M.; Rosso, Kevin M.; Heald, Steve M.; Schwartz, S. A.; Kittilstved, Kevin R.; Gamelin, Daniel R.
Photoelectrochemical etching of semiconductors
Photoelectrochemical (PEC) etching of III-V semiconductors has been used to fabricate unique structures in electronic and photonic devices, such as integral lenses on light-emitting diodes, gratings on laser structures, and through-wafer via connections ...
P. A. Kohl
Mixed Semiconductor Nanocrystal Compositions
Mixed Semiconductor Nanocrystal Compositions Mixed Semiconductor Nanocrystal Compositions Mixed Semiconductor Nanocrystal Compositions Composition comprising one or more energy donors and one or more energy acceptors. Available for thumbnail of Feynman Center (505) 665-9090 Email Mixed Semiconductor Nanocrystal Compositions Composition comprising one or more energy donors and one or more energy acceptors, wherein energy is transferred from the energy donor to the energy acceptor and wherein: the energy acceptor is a colloidal nanocrystal having a lower band gap energy than the energy donor; the energy donor and the energy acceptor are separated by a distance of 40 nm or less; wherein the average peak absorption energy of the acceptor is at least 20 meV greater than the average peak emission energy of the energy donor; and
Organization Print Organization Print 2012-12 org chart A complete ALS organization chart (June 2013) is available in PDF. Appointed and elected members of advisory panels provide guidance to Berkeley Lab and ALS management in developing the ALS scientific and user programs. ALS Staff Photo staff photo thumb Click on the image to see a recent photo of ALS staff in front of the dome. The photo was taken on May 14, 2013. ALS Management and Advisory Team Steve Kevan, Deputy Division Director, Science Michael J. Banda, Deputy Division Director, Operations Robert W. Schoenlein, Senior Staff Scientist, Next Generation Light Source Initiative Janos Kirz, Scientific Advisor Paul Adams, Division Deputy for Biosciences ALS Scientific, Technical, and User Support Groups Accelerator Physics
Blasting detonators incorporating semiconductor bridge technology
The enormity of the coal mine and extraction industries in Russia and the obvious need in both Russia and the US for cost savings and enhanced safety in those industries suggests that joint studies and research would be of mutual benefit. The author suggests that mine sites and well platforms in Russia offer an excellent opportunity for the testing of Sandia`s precise time-delay semiconductor bridge detonators, with the potential for commercialization of the detonators for Russian and other world markets by both US and Russian companies. Sandia`s semiconductor bridge is generating interest among the blasting, mining and perforation industries. The semiconductor bridge is approximately 100 microns long, 380 microns wide and 2 microns thick. The input energy required for semiconductor bridge ignition is one-tenth the energy required for conventional bridgewire devices. Because semiconductor bridge processing is compatible with other microcircuit processing, timing and logic circuits can be incorporated onto the chip with the bridge. These circuits can provide for the precise timing demanded for cast effecting blasting. Indeed tests by Martin Marietta and computer studies by Sandia have shown that such precise timing provides for more uniform rock fragmentation, less fly rock, reduce4d ground shock, fewer ground contaminants and less dust. Cost studies have revealed that the use of precisely timed semiconductor bridges can provide a savings of $200,000 per site per year. In addition to Russia`s vast mineral resources, the Russian Mining Institute outside Moscow has had significant programs in rock fragmentation for many years. He anticipated that collaborative studies by the Institute and Sandia`s modellers would be a valuable resource for field studies.
Bickes, R.W. Jr.
Method of doping a semiconductor
A method for doping semiconductor material. An interface is established between a solid electrolyte and a semiconductor to be doped. The electrolyte is chosen to be an ionic conductor of the selected impurity and the semiconductor material and electrolyte are jointly chosen so that any compound formed from the impurity and the semiconductor will have a free energy no lower than the electrolyte. A potential is then established across the interface so as to allow the impurity ions to diffuse into the semiconductor. In one embodiment the semiconductor and electrolyte may be heated so as to increase the diffusion coefficient.
Yang, Chiang Y. (Miller Place, NY); Rapp, Robert A. (Columbus, OH)
Hydrogen in semiconductors
After an incubation'' period in the 1970's and early 80's, during which the first hydrogen related centers were discovered and characterized in ultra-pure germanium, a sharp increase of research activity occurred after the discovery of shallow acceptor passivation in crystalline silicon. The aim of this review is to convey an insight into the rich, multifaceted physics and materials science which has emerged from the vast variety of experimental and theoretical studies of hydrogen in semiconductors. In order to arrive at the current understanding of hydrogen related phenomena in a logical way, each chapter will start with a brief review of the major experimental and theoretical advances of the past few years. Those who are interested to learn more about this fascinating area of semiconductor research are referred to reviews, to a number of conference proceedings volumes, and to an upcoming book which will contain authoritative chapters on most aspects of hydrogen in crystalline semiconductors. Some of the early art of semiconductor device processing can finally be put on a scientific foundation and new ways of arriving at advanced device structures begin to use what we have learned from the basic studies of hydrogen in semiconductors. 92 refs., 8 figs.
Haller, E.E. (California Univ., Berkeley, CA (USA) Lawrence Berkeley Lab., CA (USA))
Light-matter Interactions in Semiconductor Nanostructures
Light-matter interactions in Semiconductor Nanostructures. ... We investigate the interaction of light with semiconductor-based nanostructures. ...
Kansas Advanced Semiconductor Project
KASP (Kansas Advanced Semiconductor Project) completed the new Layer 0 upgrade for D0, assumed key electronics projects for the US CMS project, finished important new physics measurements with the D0 experiment at Fermilab, made substantial contributions to detector studies for the proposed e+e- international linear collider (ILC), and advanced key initiatives in non-accelerator-based neutrino physics.
Baringer, P.; Bean, A.; Bolton, T.; Horton-Smith, G.; Maravin, Y.; Ratra, B.; Stanton, N.; von Toerne, E.; Wilson, G.
Compound semiconductor MOSFETs
Enhancement mode, high electron mobility MOSFET devices have been fabricated using an oxide high-@k gate dielectric stack developed using molecular beam epitaxy. A template layer of Ga"2O"3, initially deposited on the surface of the III-V device unpins ... Keywords: Compound semiconductors, GaAs gate dielectric, III-V MOSFETs
R. Droopad; K. Rajagopalan; J. Abrokwah; P. Zurcher; M. Passlack
Amorphous semiconductor solar cell
A solar cell comprising a back electrical contact, amorphous silicon semiconductor base and junction layers and a top electrical contact includes in its manufacture the step of heat treating the physical junction between the base layer and junction layer to diffuse the dopant species at the physical junction into the base layer.
Dalal, Vikram L. (Newark, DE)
Synthetic Control of Organic Semiconductor Excited States
Al architecture. Indium-doped tin oxide (ITO) coated glassTiO 2 /Polymer/Al. Indium-doped tin oxide (ITO) coated glassAl architecture. Indium-doped tin oxide (ITO) coated glass
Clem, Tabitha Ann
overlap with the solar spectrum seen for high-performingoverlap with the AM 1.5 solar spectrum, but the materialsoverlap with the solar spectrum. In light of its superior
Novel room temperature ferromagnetic semiconductors
Today's information world, bits of data are processed by semiconductor chips, and stored in the magnetic disk drives. But tomorrow's information technology may see magnetism (spin) and semiconductivity (charge) combined in one 'spintronic' device that exploits both charge and 'spin' to carry data (the best of two worlds). Spintronic devices such as spin valve transistors, spin light emitting diodes, non-volatile memory, logic devices, optical isolators and ultra-fast optical switches are some of the areas of interest for introducing the ferromagnetic properties at room temperature in a semiconductor to make it multifunctional. The potential advantages of such spintronic devices will be higher speed, greater efficiency, and better stability at a reduced power consumption. This Thesis contains two main topics: In-depth understanding of magnetism in Mn doped ZnO, and our search and identification of at least six new above room temperature ferromagnetic semiconductors. Both complex doped ZnO based new materials, as well as a number of nonoxides like phosphides, and sulfides suitably doped with Mn or Cu are shown to give rise to ferromagnetism above room temperature. Some of the highlights of this work are discovery of room temperature ferromagnetism in: (1) ZnO:Mn (paper in Nature Materials, Oct issue, 2003); (2) ZnO doped with Cu (containing no magnetic elements in it); (3) GaP doped with Cu (again containing no magnetic elements in it); (4) Enhancement of Magnetization by Cu co-doping in ZnO:Mn; (5) CdS doped with Mn, and a few others not reported in this thesis. We discuss in detail the first observation of ferromagnetism above room temperature in the form of powder, bulk pellets, in 2-3 mu-m thick transparent pulsed laser deposited films of the Mn (<4 at. percent) doped ZnO. High-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) spectra recorded from 2 to 200nm areas showed homogeneous distribution of Mn substituting for Zn a 2+ state in the ZnO lattice. Ferromagnetic Resonance (FMR) technique is used to confirm the existence of ferromagnetic ordering at temperatures as high as 425K. The ab initio calculations were found to be consistent with the observation of ferromagnetism arising from fully polarized Mn 2+ state. The key to observed room temperature ferromagnetism in this system is the low temperature processing, which prevents formation of clusters, secondary phases and the host ZnO from becoming n-type. The electronic structure of the same Mn doped ZnO thin films studied using XAS, XES and RIXS, revealed a strong hybridization between Mn 3d and O 2p states, which is an important characteristic of a Dilute magnetic Semiconductor (DMS). It is shown that the various processing conditions like sintering temperature, dopant concentration and the properties of precursors used for making of DMS have a great influence on the final properties. Use of various experimental techniques to verify the physical properties, and to understand the mechanism involved to give rise to ferromagnetism is presented. Methods to improve the magnetic moment in Mn doped ZnO are also described. New promising DMS materials (such as Cu doped ZnO are explored). The demonstrated new capability to fabricate powder, pellets, and thin films of room temperature ferromagnetic semiconductors thus makes possible the realization of a wide range of complex elements for a variety of new multifunctional phenomena related to Spintronic devices as well as magneto-optic components.
Gupta, Amita
Definition: Semiconductor | Open Energy Information
Semiconductor Semiconductor Jump to: navigation, search Dictionary.png Semiconductor Any material that has a limited capacity for conducting an electric current. Certain semiconductors, including silicon, gallium arsenide, copper indium diselenide, and cadmium telluride, are uniquely suited to the photovoltaic conversion process.[1] View on Wikipedia Wikipedia Definition A semiconductor is a material which has electrical conductivity to a degree between that of a metal (such as copper) and that of an insulator (such as glass). Semiconductors are the foundation of modern solid state electronics, including transistors, solar cells, light-emitting diodes (LEDs), quantum dots and digital and analog integrated circuits. A semiconductor may have a number of unique properties, one of which is the
Light amplification using semiconductors
During the summer of 1953, John von Neumann discussed his ideas concerning light amplification using semiconductors with Edward Teller. In September of that year, von Neumann sent a manuscript containing his ideas and calculations on this subject to Teller for his comments. To the best of our knowledge, von Neumann did not take time to work further on these ideas, and the manuscript remained unpublished. These previously unpublished writings of John von Neumann on the subject of light amplification in semiconductors are printed as a service to the laser community. While von Neumann's original manuscript and his letter to Teller are available to anyone who visits the Library of Congress, it is much more convenient to have this paper appear in an archival journal.
Dupuis, R.D.
Isotopically controlled semiconductors
The following article is an edited transcript based on the Turnbull Lecture given by Eugene E. Haller at the 2005 Materials Research Society Fall Meeting in Boston on November 29, 2005. The David Turnbull Lectureship is awarded to recognize the career of a scientist who has made outstanding contributions to understanding materials phenomena and properties through research, writing, and lecturing, as exemplified by the life work of David Turnbull. Haller was named the 2005 David Turnbull Lecturer for his 'pioneering achievements and leadership in establishing the field of isotopically engineered semiconductors; for outstanding contributions to materials growth, doping and diffusion; and for excellence in lecturing, writing, and fostering international collaborations'. The scientific interest, increased availability, and technological promise of highly enriched isotopes have led to a sharp rise in the number of experimental and theoretical studies with isotopically controlled semiconductor crystals. This article reviews results obtained with isotopically controlled semiconductor bulk and thin-film heterostructures. Isotopic composition affects several properties such as phonon energies, band structure, and lattice constant in subtle, but, for their physical understanding, significant ways. Large isotope-related effects are observed for thermal conductivity in local vibrational modes of impurities and after neutron transmutation doping. Spectacularly sharp photoluminescence lines have been observed in ultrapure, isotopically enriched silicon crystals. Isotope multilayer structures are especially well suited for simultaneous self- and dopant-diffusion studies. The absence of any chemical, mechanical, or electrical driving forces makes possible the study of an ideal random-walk problem. Isotopically controlled semiconductors may find applications in quantum computing, nanoscience, and spintronics.
Haller, Eugene E.
Method of passivating semiconductor surfaces
A method of passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.
Wanlass, Mark W. (Golden, CO)
A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.
Wanlass, M.W.
High power semiconductor laser diode arrays
The cw optical power obtainable from semiconductor laser diodes has been extended to unprecedented levels in recent years through the use of multistripe arrays. By spreading out the optical power with more than 100 stripes, single-facet, cw output in exces of 5 Watts has been demonstrated, and 500 mW cw is now commercially available. Recent improvements to array performance include: arrays up to 1 cm wide that generates quasi-cw (150 usec pulse) output in excesss of 11 Watts, and a novel device structure which produces up to 215 mW cw in a single diffraction limited lobe.
Cross, P.S.
Visitors Far and Wide
4 4 Visitors Far and Wide From left: Minister Danilov-Daniljan, Evan Mills (Assistant Director, Center for Building Science), Victoria Mats (interpreter and Soviet energy analyst), and Len Grossman (PG&E Energy Center) tour the PG&E Energy Center in San Francisco. The Russian Minister of Ecology and Natural Resources, Victor I. Danilov-Daniljan, spent three days in California as the Center's guest. The Minister presented information on current Soviet energy and environmental dilemmas and participated in a day-long roundtable discussion with representatives of major utilities, manufacturers of energy-efficient technologies, energy regulators, nongovernmental organizations, and Center scientists. Julian Aizenberg, one of the former Soviet Union's (FSU) foremost lighting
Semiconductor devices incorporating multilayer interference regions
A semiconductor high reflector comprising a number of thin alternating layers of semiconductor materials is electrically tunable and may be used as a temperature insensitive semiconductor laser in a Fabry-Perot configuration. 8 figs.
Biefeld, R.M.; Drummond, T.J.; Gourley, P.L.; Zipperian, T.E.
Molecular Chemistry to the Fore: New Insights into the Fascinating World of Photoactive Colloidal Semiconductor Nanocrystals
Colloidal semiconductor nanocrystals possess unique properties that are unmatched by other chromophores such as organic dyes or transition-metal complexes. These versatile building blocks have generated much scientific interest and found applications in bioimaging, tracking, lighting, lasing, photovoltaics, photocatalysis, thermoelectrics, and spintronics. Despite these advances, important challenges remain, notably how to produce semiconductor nanostructures with predetermined architecture, how to produce metastable semiconductor nanostructures that are hard to isolate by conventional syntheses, and how to control the degree of surface loading or valence per nanocrystal. Molecular chemists are very familiar with these issues and can use their expertise to help solve these challenges. In this Perspective, we present our group�s recent work on bottom-up molecular control of nanoscale composition and morphology, low-temperature photochemical routes to semiconductor heterostructures and metastable phases, solar-to-chemical energy conversion with semiconductor-based photocatalysts, and controlled surface modification of colloidal semiconductors that bypasses ligand exchange.
Vela-Becerra, Javier [Ames Laboratory
Semiconductor bulk crystals and multilayer structures with controlled isotopic composition have attracted much scientific and technical interest in the past few years. Isotopic composition affects a large number of physical properties, including phonon energies and lifetimes, bandgaps, the thermal conductivity and expansion coefficient and spin-related effects. Isotope superlattices are ideal media for self-diffusion studies. In combination with neutron transmutation doping, isotope control offers a novel approach to metal-insulator transition studies. Spintronics, quantum computing and nanoparticle science are emerging fields using isotope control.
Layered semiconductor neutron detectors
Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.
Mao, Samuel S; Perry, Dale L
Method Of Transferring Strained Semiconductor Structures
Of Transferring Strained Semiconductor Structures Of Transferring Strained Semiconductor Structures Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. June 25, 2013 Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having surface contaminants. Available for thumbnail of Feynman Center (505) 665-9090 Email Method Of Transferring Strained Semiconductor Structures The transfer of strained semiconductor layers from one substrate to another substrate involves depositing a multilayer structure on a substrate having
Climate VISION: Private Sector Initiatives: Semiconductors: Resources...
Office of Scientific and Technical Information (OSTI)
FederalState Programs PFC ReductionClimate Partnership for the Semiconductor Industry Launched in 1996 in collaboration with the Semiconductor Industry Association, EPA's PFC...
Sandia National Labs: PCNSC: Research: Compound Semiconductor...
Compound Semiconductor Science and Technology Thrust The Physical, Chemical, and Nano Sciences Center's vision for Compound Semiconductors is to develop the science of compound...
Process for producing chalcogenide semiconductors
A process for producing chalcogenide semiconductor material is disclosed. The process includes forming a base metal layer and then contacting this layer with a solution having a low pH and containing ions from at least one chalcogen to chalcogenize the layer and form the chalcogenide semiconductor material.
Noufi, R.; Chen, Y.W.
Variable temperature semiconductor film deposition
A method of depositing a semiconductor material on a substrate is disclosed. The method sequentially comprises (a) providing the semiconductor material in a depositable state such as a vapor for deposition on the substrate; (b) depositing the semiconductor material on the substrate while heating the substrate to a first temperature sufficient to cause the semiconductor material to form a first film layer having a first grain size; (c) continually depositing the semiconductor material on the substrate while cooling the substrate to a second temperature sufficient to cause the semiconductor material to form a second film layer deposited on the first film layer and having a second grain size smaller than the first grain size; and (d) raising the substrate temperature, while either continuing or not continuing to deposit semiconductor material to form a third film layer, to thereby anneal the film layers into a single layer having favorable efficiency characteristics in photovoltaic applications. A preferred semiconductor material is cadmium telluride deposited on a glass/tin oxide substrate already having thereon a film layer of cadmium sulfide.
Li, X.; Sheldon, P.
Nanostructures, magnetic semiconductors and spintronics
The aim of this paper is to give a brief overview of recent advances in the area of semiconductor nanomaterials, which represent extremely promising applications for materials with the spin-polarized transport of the charge carriers. It is shown on the ... Keywords: Magnetic properties, Nanostructure, Semiconductor, Spin-polarized transport, Spintronics
Paata Kervalishvili; Alexander Lagutin
Mesoscopic Magnetic/Semiconductor Heterostructures
We report the experimental results of Fe and Fe3O4 nanostructures on GaAs(100) surfaces and hybrid Ferromagnetic/Semiconductor/Ferromagnetic (FM/SC/FM) spintronic devices. Element specific x-ray magnetic circular dichroism (XMCD) ... Keywords: Epitaxial ferromagnetic thin film, ferromagnetic/semiconductor hybrid structures, spintronics
Yong Bing Xu; E. Ahmad; Yong Xiong Lu; J. S. Claydon; Ya Zhai; G. van der Laan
Organic photosensitive cells grown on rough electrode with nano-scale morphology control
An optoelectronic device and a method for fabricating the optoelectronic device includes a first electrode disposed on a substrate, an exposed surface of the first electrode having a root mean square roughness of at least 30 nm and a height variation of at least 200 nm, the first electrode being transparent. A conformal layer of a first organic semiconductor material is deposited onto the first electrode by organic vapor phase deposition, the first organic semiconductor material being a small molecule material. A layer of a second organic semiconductor material is deposited over the conformal layer. At least some of the layer of the second organic semiconductor material directly contacts the conformal layer. A second electrode is deposited over the layer of the second organic semiconductor material. The first organic semiconductor material is of a donor-type or an acceptor-type relative to the second organic semiconductor material, which is of the other material type.
Yang, Fan (Piscataway, NJ); Forrest, Stephen R. (Ann Arbor, MI)
Hydrogen in compound semiconductors
Progress in the understanding of hydrogen and its interactions in III/V and II/VI compound semiconductors is reviewed. Donor, acceptor and deep level passivation is well established in III/V compounds based on electrical measurements and on spectroscopic studies. The hydrogen donor levels in GaAs and GaP are estimated to lie near E{sub v}+0.5 eV and E{sub v}+0.3 eV, respectively. Arsenic acceptors have been passivated by hydrogen in CdTe and the very first nitrogen-hydrogen local vibrational model spectra in ZnSe have been reported. This long awaited result may lead to an explanation for the poor activation of nitrogen acceptors in ZnSe grown by techniques which involve high concentrations of hydrogen.
Haller, E.E.
Semiconductor radiation detector
A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.
Bell, Zane W. (Oak Ridge, TN); Burger, Arnold (Knoxville, TN)
Thermal Conductivity of Polycrystalline Semiconductors and Ceramics
industries, polycrystalline semiconductors and ceramics havelaser industry, people are also seeking good ceramic laser
Wang, Zhaojie
Reactive codoping of GaAlInP compound semiconductors
A GaAlInP compound semiconductor and a method of producing a GaAlInP compound semiconductor are provided. The apparatus and method comprises a GaAs crystal substrate in a metal organic vapor deposition reactor. Al, Ga, In vapors are prepared by thermally decomposing organometallic compounds. P vapors are prepared by thermally decomposing phospine gas, group II vapors are prepared by thermally decomposing an organometallic group IIA or IIB compound. Group VIB vapors are prepared by thermally decomposing a gaseous compound of group VIB. The Al, Ga, In, P, group II, and group VIB vapors grow a GaAlInP crystal doped with group IIA or IIB and group VIB elements on the substrate wherein the group IIA or IIB and a group VIB vapors produced a codoped GaAlInP compound semiconductor with a group IIA or IIB element serving as a p-type dopant having low group II atomic diffusion.
Hanna, Mark Cooper (Boulder, CO); Reedy, Robert (Golden, CO)
Hydrogen local vibrational modes in semiconductors
Following, a review of experimental techniques, theory, and previous work, the results of local vibrational mode (LVM) spectroscopy on hydrogen-related complexes in several different semiconductors are discussed. Hydrogen is introduced either by annealing in a hydrogen ambient. exposure to a hydrogen plasma, or during growth. The hydrogen passivates donors and acceptors in semiconductors, forming neutral complexes. When deuterium is substituted for hydrogen. the frequency of the LVM decreases by approximately the square root of two. By varying the temperature and pressure of the samples, the microscopic structures of hydrogen-related complexes are determined. For group II acceptor-hydrogen complexes in GaAs, InP, and GaP, hydrogen binds to the host anion in a bond-centered orientation, along the [111] direction, adjacent to the acceptor. The temperature dependent shift of the LVMs are proportional to the lattice thermal energy U(T), a consequence of anharmonic coupling between the LVM and acoustical phonons. In the wide band gap semiconductor ZnSe, epilayers grown by metalorganic chemical vapor phase epitaxy (MOCVD) and doped with As form As-H complexes. The hydrogen assumes a bond-centered orientation, adjacent to a host Zn. In AlSb, the DX centers Se and Te are passivated by hydrogen. The second, third, and fourth harmonics of the wag modes are observed. Although the Se-D complex has only one stretch mode, the Se-H stretch mode splits into three peaks. The anomalous splitting is explained by a new interaction between the stretch LVM and multi-phonon modes of the lattice. As the temperature or pressure is varied, and anti-crossing is observed between LVM and phonon modes.
McCluskey, M.D. [Univ. of California, Berkeley, CA (United States). Dept. of Physics]|[Lawrence Berkeley National Lab., CA (United States)
Controlled buckling structures in semiconductor interconnects and nanomembranes for stretchable electronics
In an aspect, the present invention provides stretchable, and optionally printable, components such as semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed, and related methods of making or tuning such stretchable components. Stretchable semiconductors and electronic circuits preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention are adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.
Rogers, John A. (Champaign, IL); Meitl, Matthew (Raleigh, NC); Sun, Yugang (Naperville, IL); Ko, Heung Cho (Urbana, IL); Carlson, Andrew (Urbana, IL); Choi, Won Mook (Champaign, IL); Stoykovich, Mark (Dover, NH); Jiang, Hanqing (Urbana, IL); Huang, Yonggang (Glencoe, IL); Nuzzo, Ralph G. (Champaign, IL); Lee, Keon Jae (Tokyo, JP); Zhu, Zhengtao (Rapid City, SD); Menard, Etienne (Durham, NC); Khang, Dahl-Young (Seoul, KR); Kan, Seong Jun (Daejeon, KR); Ahn, Jong Hyun (Suwon, KR); Kim, Hoon-sik (Champaign, IL)
Simulating nanoscale semiconductor devices.
The next generation of electronic devices will be developed at the nanoscale and molecular level, where quantum mechanical effects are observed. These effects must be accounted for in the design process for such small devices. One prototypical nanoscale semiconductor device under investigation is a resonant tunneling diode (RTD). Scientists are hopeful the quantum tunneling effects present in an RTD can be exploited to induce and sustain THz frequency current oscillations. To simulate the electron transport within the RTD, the Wigner-Poisson equations are used. These equations describe the time evolution of the electrons distribution within the device. In this paper, this model and a parameter study using this model will be presented. The parameter study involves calculating the steady-state current output from the RTD as a function of an applied voltage drop across the RTD and also calculating the stability of that solution. To implement the parameter study, the computational model was connected to LOCA (Library of Continuation Algorithms), a part of Sandia National Laboratories parallel solver project, Trilinos. Numerical results will be presented.
Salinger, Andrew Gerhard; Zhao, P. (North Carolina State University, Raleigh, NC); Woolard, D. L. (U. S. Army Research Laboratory, NC); Kelley, C. Tim (North Carolina State University, Raleigh, NC); Lasater, Matthew S. (North Carolina State University, Raleigh, NC)
Correlated exciton dynamics in semiconductor nanostructures
The absorption and dissipation of energy in semiconductor nanostructures are often determined by excited electron dynamics. In semiconductors, one fundamentally important electronic state is an exciton, an excited electron ...
Wen, Patrick, Ph. D. Massachusetts Institute of Technology
Synchronization in semiconductor laser rings
We examine the dynamics of semiconductor lasers coupled in a ring configuration. The lasers, which have stable output intensity when isolated, behave chaotically when coupled unidirectionally in a closed chain. In this way, we show that neither feedback nor bidirectional coupling is necessary to induce chaotic dynamics at the laser output. We study the synchronization phenomena arising in this particular coupling architecture, and discuss its possible application to chaos-based communications. Next, we extend the study to bidirectional coupling and propose an appropriate technique to optical chaos encryption/decryption in closed chains of mutually coupled semiconductor lasers.
Javier M. Buldu; M. C. Torrent; Jordi Garcia-Ojalvo
Innovations in Semiconductor Devices for Exascale ...
Innovations in Semiconductor Devices for Exascale Computing. TC Chen IBM Fellow and Vice President of Science and ...
Semiconductor assisted metal deposition for nanolithography applications
An article of manufacture and method of forming nanoparticle sized material components. A semiconductor oxide substrate includes nanoparticles of semiconductor oxide. A modifier is deposited onto the nanoparticles, and a source of metal ions are deposited in association with the semiconductor and the modifier, the modifier enabling electronic hole scavenging and chelation of the metal ions. The metal ions and modifier are illuminated to cause reduction of the metal ions to metal onto the semiconductor nanoparticles.
Rajh, Tijana (Naperville, IL); Meshkov, Natalia (Downers Grove, IL); Nedelijkovic, Jovan M. (Belgrade, YU); Skubal, Laura R. (West Brooklyn, IL); Tiede, David M. (Elmhurst, IL); Thurnauer, Marion (Downers Grove, IL)
Robust Capacity Planning in Semiconductor Manufacturing
Oct 3, 2001 ... Abstract: We present a stochastic programming approach to capacity planning under demand uncertainty in semiconductor manufacturing.
Economic Impact of Measurement in the Semiconductor ...
... semiconductors are the workhorses that take electric voltage and engender ... the distance between lines of memory (dynamic random access ...
Sandia National Labs: PCNSC: Departments: Semiconductor Material...
Semiconductor Material & Device Sciences > Advanced Materials Sciences > Lasers, Optics & Remote Sensing Energy Sciences Small Science Cluster Business Office News Partnering...
Method of photocatalytic conversion of C-H organics
The present invention is the addition of a semiconductor material and energy to the reaction mixture of organic, acid (for example, trifluoroacetate), and oxygen. A transition metal ion may be added to the reaction mixture. The semiconductor material converts energy to oxidants thereby promoting oxidation of the organic. Alternatively, using metal in combination with exposure to light may be used.
Camaioni, Donald M. (Richland, WA); Lilga, Michael A. (Richland, WA)
Mechanical scriber for semiconductor devices
A mechanical scriber using a scribing tip, such as a diamond, provides controlled scriber forces with a spring-loaded compound lever arrangement. The scribing force and range of scribing depth are adjusted by a pair of adjustable micrometer heads. A semiconductor device, such as a multilayer solar cell, can be formed into scribed strips at each layer. 5 figs.
Lin, P.T.
A mechanical scriber using a scribing tip, such as a diamond, provides controlled scriber forces with a spring-loaded compound lever arrangement. The scribing force and range of scribing depth are adjusted by a pair of adjustable micrometer heads. A semiconductor device, such as a multilayer solar cell, can be formed into scribed strips at each layer.
Lin, Peter T. (East Brunswick, NJ)
National Nuclear Security Administration (NNSA)
NNSA-Wide Fiscal Year 2012 Year-End Workforce Diversity Office of Civil Rights NA-1.2 Albuquerque Complex PO Box 5400 Albuquerque, NM 87185 Phone (505) 845-5517 Fax (505) 845-4963...
White organic light-emitting diodes: Status and perspective
White organic light-emitting diodes (OLEDs) are ultrathin, large-area light sources made from organic semiconductor materials. Over the past decades, much research has been spent on finding suitable materials to realize ...
Reineke, Sebastian
Effective Community-Wide Policy Technical Assistance: The NREL...
NRELDOE Approach Jump to: navigation, search Tool Summary Name: Effective Community-Wide Policy Technical Assistance: The NRELDOE Approach AgencyCompany Organization: National...
A comparative study of semiconductor-based plasmonic metamaterials
Recent metamaterial (MM) research faces several problems when using metal-based plasmonic components as building blocks for MMs. The use of conventional metals for MMs is limited by several factors: metals such as gold and silver have high losses in the visible and near-infrared (NIR) ranges and very large negative real permittivity values, and in addition, their optical properties cannot be tuned. These issues that put severe constraints on the device applications of MMs could be overcome if semiconductors are used as plasmonic materials instead of metals. Heavily doped, wide bandgap oxide semiconductors could exhibit both a small negative real permittivity and relatively small losses in the NIR. Heavily doped oxides of zinc and indium were already reported to be good, low loss alternatives to metals in the NIR range. Here, we consider these transparent conducting oxides (TCOs) as alternative plasmonic materials for many specific applications ranging from surface-plasmon-polariton waveguides to MMs with hype...
Naik, Gururaj V; 10.1016/j.metmat.2010.11.001
Power Electronics in the Semiconductor Fabrication Industry
This report provides utility marketing and account executives and engineering staff with fundamental information about the use of power electronics systems in semiconductor fabrication equipment. It details the power electronics systems used in typical semiconductor production equipment as well as current topology and system compatibility issues. Finally, the report outlines how power electronics will serve future advances in the semiconductor industry and how utilities can help the industry make their e...
Optical devices featuring textured semiconductor layers
A semiconductor sensor, solar cell or emitter, or a precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate. The textured layers enhance light extraction or absorption. Texturing in the region of multiple quantum wells greatly enhances internal quantum efficiency if the semiconductor is polar and the quantum wells are grown along the polar direction. Electroluminescence of LEDs of the invention is dichromatic, and results in variable color LEDs, including white LEDs, without the use of phosphor.
Moustakas, Theodore D. (Dover, MA); Cabalu, Jasper S. (Cary, NC)
Lattice matched semiconductor growth on crystalline ...
Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a metal or ...
Low Energy Ion Implantationin Semiconductor Manufacturing | U...
Office of Science (SC) Website
Low Energy Ion Implantation in Semiconductor Manufacturing Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications Spinoff...
Stangl Semiconductor Equipment AG | Open Energy Information
Solar Product German manufacturer of wet chemistry systems for processing silicon and thin-film solar cells. References Stangl Semiconductor Equipment AG1 LinkedIn...
Low Energy Ion Implantation in Semiconductor Manufacturing Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Spinoff Applications SBIRSTTR...
Climate VISION: Private Sector Initiatives: Semiconductors: Work...
Work Plans The Semiconductor Industry Association has finalized its work plan with the collaboration of EPA. The plan describes actions the industry intends to take to achieve its...
Implications of mercury interactions with band-gap semiconductor oxides
Titanium dioxide is a well-known photooxidation catalyst. It will oxidize mercury in the presence of ultraviolet light from the sun and oxygen and/or moisture to form mercuric oxide. Several companies manufacture self-cleaning windows. These windows have a transparent coating of titanium dioxide. The titanium dioxide is capable of destroying organic contaminants in air in the presence of ultraviolet light from the sun, thereby keeping the windows clean. The commercially available self-cleaning windows were used to sequester mercury from oxygen�nitrogen mixtures. Samples of the self-cleaning glass were placed into specially designed photo-reactors in order to study the removal of elemental mercury from oxygen�nitrogen mixtures resembling air. The possibility of removing mercury from ambient air with a self-cleaning glass apparatus is examined. The intensity of 365-nm ultraviolet light was similar to the natural intensity from sunlight in the Pittsburgh region. Passive removal of mercury from the air may represent an option in lieu of, or in addition to, point source clean-up at combustion facilities. There are several common band-gap semiconductor oxide photocatalysts. Sunlight (both the ultraviolet and visible light components) and band-gap semiconductor particles may have a small impact on the global cycle of mercury in the environment. The potential environmental consequences of mercury interactions with band-gap semiconductor oxides are discussed. Heterogeneous photooxidation might impact the global transport of elemental mercury emanating from flue gases.
Granite, E.J.; King, W.P.; Stanko, D.C.; Pennline, H.W.
Business Case Slide 28: High-Value: Semiconductors - Program...
Semiconductors - Program Focus Previous Slide Next Slide Table of Contents High-Value: Semiconductors - Program Focus Measurement of DUO2 transistor properties at ORNL Measurement...
Stable surface passivation process for compound semiconductors
A passivation process for a previously sulfided, selenided or tellurated III-V compound semiconductor surface. The concentration of undesired mid-gap surface states on a compound semiconductor surface is reduced by the formation of a near-monolayer of metal-(sulfur and/or selenium and/or tellurium)-semiconductor that is effective for long term passivation of the underlying semiconductor surface. Starting with the III-V compound semiconductor surface, any oxidation present thereon is substantially removed and the surface is then treated with sulfur, selenium or tellurium to form a near-monolayer of chalcogen-semiconductor of the surface in an oxygen-free atmosphere. This chalcogenated surface is then contacted with a solution of a metal that will form a low solubility chalcogenide to form a near-monolayer of metal-chalcogen-semiconductor. The resulting passivating layer provides long term protection for the underlying surface at or above the level achieved by a freshly chalcogenated compound semiconductor surface in an oxygen free atmosphere.
Ashby, Carol I. H. (Edgewood, NM)
Preparation of a semiconductor thin film
A process for the preparation of a semiconductor film. The process comprises depositing nanoparticles of a semiconductor material onto a substrate whose surface temperature during nanoparticle deposition thereon is sufficient to cause substantially simultaneous fusion of the nanoparticles to thereby coalesce with each other and effectuate film growth.
Pehnt, Martin (TuBingen, DE); Schulz, Douglas L. (Denver, CO); Curtis, Calvin J. (Lakewood, CO); Ginley, David S. (Evergreen, CO)
Semiconductor liquid-junction solar cell
A semiconductor liquid junction photocell in which the photocell is in the configuration of a light concentrator and in which the electrolytic solution both conducts current and facilitates the concentration of incident solar radiation onto the semiconductor. The photocell may be in the configuration of a non-imaging concentrator such as a compound parabolic concentrator, or an imaging concentrator such as a lens.
Parkinson, B.A.
Island Wide Management Corporation
Office of Legacy Management (LM)
9 1986 9 1986 Island Wide Management Corporation 3000 Marcus Avenue Lake Success, New York 11042 Dear Sir or Madam: I am sending you this letter and the enclosed information as you have been identified by L. I. Trinin of Glick Construction Company as the representatives of the owners of the property that was formerly the site of the Sylvania-Corning Nuclear Corporation in Bayside, New York. The Department of Energy is evaluating the radiological condition of sites that were utilized under the Manhattan Engineer District and/or the Atomic Energy Commission in the early years of nuclear energy development to determine whether they need remedial action and whether the Department has authority to perform such action. As you may know, the former Sylvania-Corning Corporation Bayside site was identified as one such site.
Semiconductor switch geometry with electric field shaping
An optoelectric switch is disclosed that utilizes a cylindrically shaped and contoured GaAs medium or other optically active semiconductor medium to couple two cylindrically shaped metal conductors with flat and flared termination points each having an ovoid prominence centrally extending there from. Coupling the truncated ovoid prominence of each conductor with the cylindrically shaped optically active semiconductor causes the semiconductor to cylindrically taper to a triple junction circular line at the base of each prominence where the metal conductor conjoins with the semiconductor and a third medium such as epoxy or air. Tapering the semiconductor at the triple junction inhibits carrier formation and injection at the triple junction and thereby enables greater current carrying capacity through and greater sensitivity of the bulk area of the optically active medium.
Booth, Rex (Livermore, CA); Pocha, Michael D. (Livermore, CA)
the World Wide Web
technical report has been made technical report has been made electronically available on the World Wide Web through a contribution from Walter L. Warnick In honor of Enrico Fermi Leader of the first nuclear reactor, Nobel Prize winner, and visionary technologist Dr. Warnick is delighted to be the first sponsor for posting a Department of Energy technical report and making it broadly available Office of Scientific and Technical Information Office of Science U.S. Department of Energy September 2008 osti.gov U N I T E D S T A T E S A T O M I C E N E R G Y C O M M I S S I O N AECD-3269 EXPERIMENTAL PRODUCTION OF A DNERGENT CHAIN REACTION BY E. Fermi January 4, 1952 [TIS Issuance ate] [chicago University] - T e c h n i c a l I n f o r m a t i o n S e r v i c e , O a k Ridge, T e n n e s s e e r ABSTRACTS Description of the construction and operation of the chain
Semiconductor Nanoclusters as Potential Photocatalysts
High Power Electronics Based on the 2-Dimensional Electron Gas in GaN High Power Electronics Based on the 2-Dimensional Electron Gas in GaN Heterostructures by S. R. Kurtz, A. A. Allerman, and D. Koleski Motivation-GaN-based electronics offer miniaturization potential of radical proportions for microwave power amplifiers. GaN's large bandgap, high breakdown field, high electron velocity, and excellent thermal properties have led to high electron mobility transistors (HEMT) with up to 10x the power density of GaAs and other traditional semiconductors at frequencies up to 20 GHz. Further contributing to the outstanding performance of GaN-based amplifiers is the highly conducting, 2-dimensional electron gas (2DEG) used for the HEMT channel. Intrinsic polarization and piezoelectric properties of GaN materials can produce a 2DEG at an
Phosphorus doping a semiconductor particle
A method of phosphorus doping a semiconductor particle using ammonium phosphate is disclosed. A p-doped silicon sphere is mixed with a diluted solution of ammonium phosphate having a predetermined concentration. These spheres are dried with the phosphorus then being diffused into the sphere to create either a shallow or deep p-n junction. A good PSG glass layer is formed on the surface of the sphere during the diffusion process. A subsequent segregation anneal process is utilized to strip metal impurities from near the p-n junction into the glass layer. A subsequent HF strip procedure is then utilized to removed the PSG layer. Ammonium phosphate is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirement. 1 fig.
Stevens, G.D.; Reynolds, J.S.
Semiconductor processing with excimer lasers
The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Extensive comparisons of the quality of annealing of ion-implanted Si obtained with XeCl and ruby lasers have been made. The results indicate that irrespective of the large differences in the optical properties of Si at uv and visible wavelengths, the efficiency of usage of the incident energy for annealing is comparable for the two lasers. However, because of the excellent optical beam quality, the XeCl laser can provide superior control of the surface melting and the resulting junction depth. Furthermore, the concentrations of electrically active point defects in the XeCl laser annealed region are 2 to 3 orders of magnitude lower than that obtained from ruby or Nd:YAG lasers. All these results seem to suggest that XeCl lasers should be suitable for fabricating not only solar cells but also the more advanced device structures required for VLSI or VHSIC applications.
Young, R.T.; Narayan, J.; Christie, W.H.; van der Leeden, G.A.; Rothe, D.E.; Cheng, L.J.
Excess charges in semiconductor nanocrystallites
The authors explore in this report the effects of excess electrons on the edge of the absorption spectrum of small semiconductor particles. The presence of these charges leads to strong bleaching of the absorption at the exciton region and to slight enhancement of the absorption on both sides of the bleaching. They show that the effect is independent of the origin of the charge; it occurs whether the charge is injected into the particle or only attached to its surface, and it appears even when the charge is deeply localized within the band gap. They conclude that the effect arises from the electric field associated with the charge and not from its presence in the band.
Laungdilok, C.; Lawless, D.; Cook, A.R.; Meisel, D. [Argonne National Lab., IL (United States). Chemistry Div.
Heating device for semiconductor wafers
An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. For instance, in one embodiment, the light energy sources form a spiral configuration. In an alternative embodiment, the light energy sources appear to be randomly dispersed with respect to each other so that no discernible pattern is present. In a third alternative embodiment of the present invention, the light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light. 4 figs.
Vosen, S.R.
An apparatus for heat treating semiconductor wafers is disclosed. The apparatus includes a heating device which contains an assembly of light energy sources for emitting light energy onto a wafer. In particular, the light energy sources are positioned such that many different radial heating zones are created on a wafer being heated. For instance, in one embodiment, the light energy sources form a spiral configuration. In an alternative embodiment, the light energy sources appear to be randomly dispersed with respect to each other so that no discernable pattern is present. In a third alternative embodiment of the present invention, the light energy sources form concentric rings. Tuning light sources are then placed in between the concentric rings of light.
Vosen, Steven R. (Berkeley, CA)
Boron doping a semiconductor particle
A method (10,30) of boron doping a semiconductor particle using boric acid to obtain a p-type doped particle. Either silicon spheres or silicon powder is mixed with a diluted solution of boric acid having a predetermined concentration. The spheres are dried (16), with the boron film then being driven (18) into the sphere. A melt procedure mixes the driven boron uniformly throughout the sphere. In the case of silicon powder, the powder is metered out (38) into piles and melted/fused (40) with an optical furnace. Both processes obtain a p-type doped silicon sphere with desired resistivity. Boric acid is not a restricted chemical, is inexpensive, and does not pose any special shipping, handling, or disposal requirements.
Stevens, Gary Don (18912 Ravenglen Ct., Dallas, TX 75287); Reynolds, Jeffrey Scott (703 Horizon, Murphy, TX 75094); Brown, Louanne Kay (2530 Poplar Tr., Garland, TX 75042)
Energy Management in Semiconductor Cleanrooms
6 6 Energy Management in Semiconductor Cleanrooms Cleanrooms are used extensively in the manufacturing of integrated circuits and in the biological and pharmaceutical industries. For particle concentrations to remain low, for example, less than 100 particles/ft3 at >0.5 micrometers (Class 100), the air in the cleanroom must be filtered. Typically, the air is circulated through high-efficiency particulate air (HEPA) filters at a very high rate, such as 400 to 600 room air volumes per hour, to maintain low particle concentrations. The combined effect of high recirculation and a high pressure drop through HEPA filters is higher power costs per unit floor area to operate the cleanroom than to ventilate a commercial building. Cleanrooms are usually ventilated constantly and
Novel patterning techniques for manufacturing organic and nanostructured electronics
Molecular organic semiconductors and nanometer size particles are two new classes of functional materials allowing fabrication of electronic devices on low-cost and large area substrates. Patterning these electronic materials ...
Chen, Jianglong, 1976-
Photosynthesis-inspired device architectures for organic photovoltaics
Organic semiconductor photovoltaics offer a promising route to low-cost, scalable, emissions-free electricity generation. However, achieving higher power conversion efficiencies is critical before these devices can play a ...
Heidel, Timothy David
A World Wide Web Update
A World Wide Web Update The Center for Building Science now has a World Wide Web homepage accessible from the general LBL homepage. Through WWW and the Mosaic browser, Internet...
OSRAM OPTO SEMICONDUCTORS, INC. FOR AN ADVANCE WAIVER OSRAM OPTO SEMICONDUCTORS, INC. FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN INVENTION RIGHTS UNDER DOE COOPERATIVE AGREEMENT NO. DE-FC26-04NT41947; W(A)-04-021, CH-1190 The Petitioner, Osram Opto Semiconductors (Osram), was awarded this cooperative agreement for the performance of work entitled, "Polymer OLED White Light Development Program." In this program, Osram will develop, fabricate, and fully characterize a 12-inch square OLED (Organic Light Emitting Diode) white light prototype. The prototype will be based on use of multiple discrete 3-inch square white light devices fabricated on glass substrates. A broadband light-emitting co-polymer for the generation of white light, from either a single large area emitting film, or from a relatively small number of segmented emitting films will be used. An alternate
Hemlock Semiconductor Corp HSC | Open Energy Information
Hemlock Semiconductor Corp HSC Hemlock Semiconductor Corp HSC Jump to: navigation, search Name Hemlock Semiconductor Corp (HSC) Place Hemlock, Michigan Zip 48626 Sector Solar Product US-based manufacturer polycrystalline silicon for semiconductor and solar industries. Coordinates 39.589497°, -82.153275° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":39.589497,"lon":-82.153275,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Climate VISION: Private Sector Initiatives: Semiconductors
Letters of Intent/Agreements Letters of Intent/Agreements The U.S. semiconductor industry, represented by the members of the Environmental Protection Agency's PFC Reduction/Climate Partnership for the Semiconductor Industry, has committed to reduce absolute perfluorocompound (PFC) emissions by 10% below the 1995 baseline level by the year 2010. Perfluorocompounds include the most potent and long-lived greenhouse gases such as perfluorocarbons (e.g., CF4, C2F6, C3F8), trifluoromethane (CHF3), nitrogen trifluoride (NF3), and sulfur hexafluoride (SF6). The Environmental Protection Agency's (EPA) voluntary semiconductor industry partnership was developed collaboratively with the Semiconductor Industry Association (SIA). EPA, SIA, and the Partner companies (listed below) are working to reduce industry greenhouse gas (GHG) emissions. EPA's
Science and applications of infrared semiconductor nanocrystals
In this work we study several applications of semiconductor nanocrystals (NCs) with infrared band gaps. In the first half, we explore the physics of two systems with applications in NC based photovoltaics. The physics of ...
Geyer, Scott Mitchell
High Aspect Ratio Semiconductor Heterojunction Solar Cells
High Aspect Ratio Semiconductor Heterojunction Solar Cells Haoting Shen Prof. Redwing's Research and in-situ dopant for Si nanowires Y. Ke, X.J. Weng, J.M. Redwing, C.M. Eichfeld, T.R. Swisher, S
Yener, Aylin
Developing New Nanoprobes from Semiconductor Nanocrystals
Water-Soluble Silica- Coated CdSe/ZnS Semiconductor QuantumEnhanced Luminescence of CdSe Quantum Dots on Gold Colloids.CdS/ZnS shells on colloidal CdSe nanorods. Journal Of The
Fu, Aihua
Thermovoltaic semiconductor device including a plasma filter
A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.
Baldasaro, Paul F. (Clifton Park, NY)
Semiconductor-nanocrystal/conjugated polymer thin films
The invention described herein provides for thin films and methods of making comprising inorganic semiconductor-nanocrystals dispersed in semiconducting-polymers in high loading amounts. The invention also describes photovoltaic devices incorporating the thin films.
Alivisatos, A. Paul (Oakland, CA); Dittmer, Janke J. (Munich, DE); Huynh, Wendy U. (Munich, DE); Milliron, Delia (Berkeley, CA)
Gaining creative control over semiconductor nanowires
Gaining creative control over semiconductor nanowires Gaining creative control over semiconductor nanowires Gaining creative control over semiconductor nanowires Using a microfluidic reactor, Los Alamos researchers transformed the SLS process into a flow-based technique. September 26, 2013 Growth of nanowire precursors in a flowing carrier solvent Growth of nanowire precursors in a flowing carrier solvent The new "flow" solution-liquid-solid method allows scientists to slow down growth and thereby capture mechanistic details as the nanowires grow in solution. A Los Alamos research team has transformed the synthesis process of semiconductor nanowires for use in solar cells, batteries, electronics, sensors and photonics using a solution-liquid-solid (SLS) batch approach to achieve unprecedented control over growth rates, nanowire size and internal
Mospec Semiconductor Corp | Open Energy Information
Mospec Semiconductor Corp Mospec Semiconductor Corp Jump to: navigation, search Name Mospec Semiconductor Corp Place Tainan, Taiwan Sector Solar Product Taiwanese semiconductor products producer; offers monocrystalline silicon wafers and as of April 2008, ingots for the solar industry. Coordinates 22.99721°, 120.180862° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":22.99721,"lon":120.180862,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Optical temperature indicator using thermochromic semiconductors
A reversible optical temperature indicator utilizes thermochromic semiconductors which vary in color in response to various temperature levels. The thermochromic material is enclosed in an enamel which provides protection and prevents breakdown at higher temperatures. Cadmium sulfide is the preferred semiconductor material. The indicator may be utilized as a sign or in a striped arrangement to clearly provide a warning to a user. The various color responses provide multiple levels of alarm.
Kronberg, J.W.
Optical devices featuring nonpolar textured semiconductor layers
A semiconductor emitter, or precursor therefor, has a substrate and one or more textured semiconductor layers deposited onto the substrate in a nonpolar orientation. The textured layers enhance light extraction, and the use of nonpolar orientation greatly enhances internal quantum efficiency compared to conventional devices. Both the internal and external quantum efficiencies of emitters of the invention can be 70-80% or higher. The invention provides highly efficient light emitting diodes suitable for solid state lighting.
Moustakas, Theodore D; Moldawer, Adam; Bhattacharyya, Anirban; Abell, Joshua
Electron gas grid semiconductor radiation detectors
An electron gas grid semiconductor radiation detector (EGGSRAD) useful for gamma-ray and x-ray spectrometers and imaging systems is described. The radiation detector employs doping of the semiconductor and variation of the semiconductor detector material to form a two-dimensional electron gas, and to allow transistor action within the detector. This radiation detector provides superior energy resolution and radiation detection sensitivity over the conventional semiconductor radiation detector and the "electron-only" semiconductor radiation detectors which utilize a grid electrode near the anode. In a first embodiment, the EGGSRAD incorporates delta-doped layers adjacent the anode which produce an internal free electron grid well to which an external grid electrode can be attached. In a second embodiment, a quantum well is formed between two of the delta-doped layers, and the quantum well forms the internal free electron gas grid to which an external grid electrode can be attached. Two other embodiments which are similar to the first and second embodiment involve a graded bandgap formed by changing the composition of the semiconductor material near the first and last of the delta-doped layers to increase or decrease the conduction band energy adjacent to the delta-doped layers.
Optical Nonlinearities and Ultrafast Carrier Dynamics in Semiconductor Quantum Dots
Low-dimensional semiconductors have attracted great interest due to the potential for tailoring their linear and nonlinear optical properties over a wide-range. Semiconductor nanocrystals (NC's) represent a class of quasi-zero-dimensional objects or quantum dots. Due to quantum cordhement and a large surface-to-volume ratio, the linear and nonlinear optical properties, and the carrier dynamics in NC's are significantly different horn those in bulk materials. napping at surface states can lead to a fast depopulation of quantized states, accompanied by charge separation and generation of local fields which significantly modifies the nonlinear optical response in NC's. 3D carrier confinement also has a drastic effect on the energy relaxation dynamics. In strongly confined NC's, the energy-level spacing can greatly exceed typical phonon energies. This has been expected to significantly inhibit phonon-related mechanisms for energy losses, an effect referred to as a phonon bottleneck. It has been suggested recently that the phonon bottleneck in 3D-confined systems can be removed due to enhanced role of Auger-type interactions. In this paper we report femtosecond (fs) studies of ultrafast optical nonlinearities, and energy relaxation and trap ping dynamics in three types of quantum-dot systems: semiconductor NC/glass composites made by high temperature precipitation, ion-implanted NC's, and colloidal NC'S. Comparison of ultrafast data for different samples allows us to separate effects being intrinsic to quantum dots from those related to lattice imperfections and interface properties.
Klimov, V.; McBranch, D.; Schwarz, C.
Spin Transport in Semiconductor heterostructures
The focus of the research performed under this grant has been the investigation of spin transport in magnetic semiconductor heterostructures. The interest in these systems is motivated both by their intriguing physical properties, as the physical embodiment of a spin-polarized Fermi liquid, as well as by their potential applications as spintronics devices. In our work we have analyzed several different problems that affect the spin dynamics in single and bi-layer spin-polarized two-dimensional (2D) systems. The topics of interests ranged from the fundamental aspects of the electron-electron interactions, to collective spin and charge density excitations and spin transport in the presence of the spin-orbit coupling. The common denominator of these subjects is the impact at the macroscopic scale of the spin-dependent electron-electron interaction, which plays a much more subtle role than in unpolarized electron systems. Our calculations of several measurable parameters, such as the excitation frequencies of magneto-plasma modes, the spin mass, and the spin transresistivity, propose realistic theoretical estimates of the opposite-spin many-body effects, in particular opposite-spin correlations, that can be directly connected with experimental measurements.
Domnita Catalina Marinescu
Photoelectrochemistry of Semiconductor Nanowire Arrays
This project supported research on the growth and photoelectrochemical characterization of semiconductor nanowire arrays, and on the development of catalytic materials for visible light water splitting to produce hydrogen and oxygen. Silicon nanowires were grown in the pores of anodic aluminum oxide films by the vapor-liquid-solid technique and were characterized electrochemically. Because adventitious doping from the membrane led to high dark currents, silicon nanowire arrays were then grown on silicon substrates. The dependence of the dark current and photovoltage on preparation techniques, wire diameter, and defect density was studied for both p-silicon and p-indium phosphide nanowire arrays. The open circuit photovoltage of liquid junction cells increased with increasing wire diameter, reaching 350 mV for micron-diameter silicon wires. Liquid junction and radial p-n junction solar cells were fabricated from silicon nano- and microwire arrays and tested. Iridium oxide cluster catalysts stabilized by bidentate malonate and succinate ligands were also made and studied for the water oxidation reaction. Highlights of this project included the first papers on silicon and indium phosphide nanowire solar cells, and a new procedure for making ligand-stabilized water oxidation catalysts that can be covalently linked to molecular photosensitizers or electrode surfaces.
Mallouk, Thomas E; Redwing, Joan M
Glass, Plastic and Semiconductors: Packaging Techniques for Miniature Optoelectric Components
At Lawrence Livermore National Laboratory, they have extensive experience with the design and development of miniature photonic systems which require novel packaging schemes. Over the years they have developed silicon micro-optical benches to serve as a stable platform for precision mounting of optical and electronic components. They have developed glass ball lenses that can be fabricated in-situ on the microbench substrate. They have modified commercially available molded plastic fiber ribbon connectors (MT) and added thin film multilayer semiconductor coatings to create potentially low-cost wavelength combiners and wavelength selective filters. They have fabricated both vertical-cavity and in-plane semiconductor lasers and amplifiers, and have packaged these and other components into several miniature photonics systems. For example, they have combined the silicon optical bench with standard electronic packaging techniques and the custom-made wavelength-selective filters to develop a four-wavelength wavelength-division-multiplexing transmitter module mounted in a standard 120-pin ceramic PGA package that couples light from several vertical-cavity-surface-emitting-laser arrays into one multimode fiber-ribbon array. The coupling loss can be as low as 2dB, and the transmitters can be operated at over 1.25 GHz. While these systems were not designed for biomedical or environmental applications, the concepts and techniques are general and widely applicable.
Pocha, M.D.; Garrett, H.E.; Patel, R.R.; Jones II, L.M.; Larson, M.C.; Emanuel, M.A.; Bond, S.W.; Deri, R.J.; Drayton, R.F.; Peterson, H.E.; Lowry, M.E.
Organic Electronics: Materials, Processing, Devices and Applications, 1st edition
In the near future, organic semiconductors may be used in a variety of products, including flat-screen TVs, e-book readers, and third-generation organic photovoltaics applications, to name just a few. While organic electronics has received increased ...
Franky So
Photodeposition of Pt on Colloidal CdS and CdSe/CdS Semiconductor Nanostructures
Semiconductor photocatalysis has been identified as a promising avenue for the conversion of solar energy into environmentally friendly fuels, most notably by the production of hydrogen from water.[1-5] Nanometer-scale materials in particular have attracted considerable scientific attention as the building blocks for light-harvesting applications.[6,7] Their desirable attributes include tunability of the optical properties with size, amenability to relatively inexpensive low-temperature processing, and a high degree of synthetic sophistication leading to increasingly complex and multi-functional architectures. For photocatalysis in particular, the high surface-to-volume ratios in nanoscale materials should lead to an increased availability of carriers for redox reactions on the nanoparticle surface. Recombination of photoexcited carriers directly competes with photocatalytic activity.[3] Charge separation is often achieved with multi-component heterostructures. An early example is the case of TiO2 powders functionalized with Pt and RuO2 particles, where photoexcited electrons are transferred to Pt (the reduction site) and holes to RuO2 (the oxidation site).[8] More recently, many colloidally synthesized nanometer-scale metal-semiconductor heterostructures have been reported.[7,9,10] A majority of these structures are made by thermal methods.[7,10] We have chosen to study photochemical formation of metal-semiconductor heterostructures. The detailed understanding of the mechanisms involved in photodeposition of metals on nanometer-scale semiconductors is necessary to enable a high degree of synthetic control. At the same time, because the results of metal deposition can be directly observed by electron microscopy, it can be used to understand how factors such as nanocrystal composition, shape, carrier dynamics, and surface chemistry influence the photochemical properties of semiconductor nanocrystals. In this communication, we report on the photodeposition of Pt on colloidal CdS and CdSe/CdS core/shell nanocrystals. Among the II-VI semiconductors, CdS is of particular interest because it has the correct band alignment for water photolysis[2] and has been demonstrated to be photocatalytically active.[11-16] We have found that the photoexcitation of CdS and CdSe/CdS in the presence of an organometallic Pt precursor leads to deposition of Pt nanoparticles on the semiconductor surface. Stark differences are observed in the Pt nanoparticle location on the two substrates, and the photodeposition can be completely inhibited by the modification of the semiconductor surface. Our results suggest that tuning of the semiconductor band structure, spatial organization and surface chemistry should be crucial in the design of photocatalytic nanostructures.
Dukovic, Gordana; Merkle, Maxwell G.; Nelson, James H.; Hughes, Steven M.; Alivisatos, A. Paul
Method for removing semiconductor layers from salt substrates
A method is described for removing a CVD semiconductor layer from an alkali halide salt substrate following the deposition of the semiconductor layer. The semiconductor-substrate combination is supported on a material such as tungsten which is readily wet by the molten alkali halide. The temperature of the semiconductor-substrate combination is raised to a temperature greater than the melting temperature of the substrate but less than the temperature of the semiconductor and the substrate is melted and removed from the semiconductor by capillary action of the wettable support.
Shuskus, Alexander J. (West Hartford, CT); Cowher, Melvyn E. (East Brookfield, MA)
High-power semiconductor separate-confinement double heterostructure lasers
The review is devoted to high-power semiconductor lasers. Historical reference is presented, physical and technological foundations are considered, and the concept of high-power semiconductor lasers is formulated. Fundamental and technological reasons limiting the optical power of a semiconductor laser are determined. The results of investigations of cw and pulsed high-power semiconductor lasers are presented. Main attention is paid to inspection of the results of experimental studies of single high-power semiconductor lasers. The review is mainly based on the data obtained in the laboratory of semiconductor luminescence and injection emitters at the A.F. Ioffe Physicotechnical Institute. (review)
Tarasov, I S [A.F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg (Russian Federation)
Light sources based on semiconductor current filaments
The present invention provides a new type of semiconductor light source that can produce a high peak power output and is not injection, e-beam, or optically pumped. The present invention is capable of producing high quality coherent or incoherent optical emission. The present invention is based on current filaments, unlike conventional semiconductor lasers that are based on p-n junctions. The present invention provides a light source formed by an electron-hole plasma inside a current filament. The electron-hole plasma can be several hundred microns in diameter and several centimeters long. A current filament can be initiated optically or with an e-beam, but can be pumped electrically across a large insulating region. A current filament can be produced in high gain photoconductive semiconductor switches. The light source provided by the present invention has a potentially large volume and therefore a potentially large energy per pulse or peak power available from a single (coherent) semiconductor laser. Like other semiconductor lasers, these light sources will emit radiation at the wavelength near the bandgap energy (for GaAs 875 nm or near infra red). Immediate potential applications of the present invention include high energy, short pulse, compact, low cost lasers and other incoherent light sources.
Zutavern, Fred J. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Buttram, Malcolm T. (Sandia Park, NM); Mar, Alan (Albuquerque, NM); Helgeson, Wesley D. (Albuquerque, NM); O' Malley, Martin W. (Edgewood, NM); Hjalmarson, Harold P. (Albuquerque, NM); Baca, Albert G. (Albuquerque, NM); Chow, Weng W. (Cedar Crest, NM); Vawter, G. Allen (Albuquerque, NM)
Total organic carbon (TOC) and chemical oxygen demand (COD) - Monitoring of organic pollutants in wastewater.
?? Total organic carbon (TOC) and chemical oxygen demand (COD) are two methods used for measuring organic pollutants in wastewater. Both methods are widely used� (more)
Hodzic, Elvisa
Zecon Solar Semiconductor Inc | Open Energy Information
Zecon Solar Semiconductor Inc Zecon Solar Semiconductor Inc Jump to: navigation, search Name Zecon Solar & Semiconductor Inc Place Cupertino, California Zip 95014 Sector Solar Product Focused on large-scale solar building integrated PV systems. Coordinates 37.31884°, -122.029244° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.31884,"lon":-122.029244,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Substrate solder barriers for semiconductor epilayer growth
During the growth of compound semiconductors by epitaxial processes, substrates are typically mounted to a support. In molecular beam epitaxy, mounting is done using indium as a solder. This method has two drawbacks: the indium reacts with the substrate, and it is difficult to uniformly wet the back of a large diameter substrate. Both of these problems have been successfully overcome by sputter coating the back of the substrate with a thin layer of tungsten carbide or tungsten carbide and gold. In addition to being compatible with the growth of high quality semiconductor epilayers this coating is also inert in all standard substate cleaning etchants used for compound semiconductors, and provides uniform distribution of energy in radiant heating. 1 tab.
Drummond, T.J.; Ginley, D.S.; Zipperian, T.E.
Emissivity Correcting Pyrometry of Semiconductor Growth
Emissivity Correcting Pyrometry of Semiconductor Growth Emissivity Correcting Pyrometry of Semiconductor Growth by W. G. Breiland, L. A. Bruskas, A. A. Allerman, and T. W. Hargett Motivation-Temperature is a critical factor in the growth of thin films by either chemical vapor deposition (CVD) or molecular beam epitaxy (MBE). It is particularly important in compound semiconductor growth because one is often challenged to grow materials with specific chemical compositions in order to maintain stringent lattice-matching conditions or to achieve specified bandgap values. Optical pyrometry can be used to measure surface temperatures, but the thin film growth causes significant changes in the emissivity of the surface, leading to severe errors in the pyrometer measurement. To avoid these errors, emissivity changes must be measured and
Coherent optical control of electronic excitations in functionalized semiconductor nanostructures
The feasibility of creating and manipulating coherent quantum states on surfaces offunctionalized semiconductor nanostructures is computationally investigated. Quantumdynamics simulations of electron-hole transfer between catechol molecules adsorbed ... Keywords: adsorbates, coherent control, semiconductors, wave-packet dynamics
L. G. C. Rego; S. G. Abuabara; V. S. Batista
Business Case Slide 27: High-Value: Semiconductors - Basis for...
Semiconductors - Basis for Use Basis for use DUO2 has good electronic properties for semi-conductor applications Have made and tested a diode and transistor which appear superior...
Business Case Slide 25: High-Value: Semiconductors - Description
Semiconductors - Description Receipt of rare DUO crystals at ORNL Receipt of rare DUO2 crystals at ORNL Description Use DUO2 as a semiconductor material Computer CPU or RAM chips...
Lattice mismatched compound semiconductors and devices on silicon
III-V compound semiconductors, due to their superior electron mobility, are promising candidates for n-type metal-oxide-semiconductor field effect transistors (MOSFETs). However, the limited size of III-V substrates and ...
Yang, Li, Ph. D. Massachusetts Institute of Technology
Surface passivation process of compound semiconductor material using UV photosulfidation
A method for passivating compound semiconductor surfaces by photolytically disrupting molecular sulfur vapor with ultraviolet radiation to form reactive sulfur which then reacts with and passivates the surface of compound semiconductors.
Taiwan Semiconductor Manufacturing Co Ltd TSMC | Open Energy Information
Semiconductor Manufacturing Co Ltd TSMC Semiconductor Manufacturing Co Ltd TSMC Jump to: navigation, search Name Taiwan Semiconductor Manufacturing Co Ltd (TSMC) Place Hsinchu, Taiwan Zip 300 Sector Solar Product Taiwan-based semiconductor company. The firm is also venturing into solar and LED production. References Taiwan Semiconductor Manufacturing Co Ltd (TSMC)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Taiwan Semiconductor Manufacturing Co Ltd (TSMC) is a company located in Hsinchu, Taiwan . References ↑ "Taiwan Semiconductor Manufacturing Co Ltd (TSMC)" Retrieved from "http://en.openei.org/w/index.php?title=Taiwan_Semiconductor_Manufacturing_Co_Ltd_TSMC&oldid=352012"
Method Of Transferring A Thin Crystalline Semiconductor Layer
Method Of Transferring A Thin Crystalline Semiconductor Layer Method Of Transferring A Thin Crystalline Semiconductor Layer Method Of Transferring A Thin Crystalline Semiconductor Layer A method for transferring a thin semiconductor layer from one substrate to another substrate involves depositing a thin epitaxial monocrystalline semiconductor layer on a substrate having surface contaminants. Available for thumbnail of Feynman Center (505) 665-9090 Email Method Of Transferring A Thin Crystalline Semiconductor Layer A method for transferring a thin semiconductor layer from one substrate to another substrate involves depositing a thin epitaxial monocrystalline semiconductor layer on a substrate having surface contaminants. An interface that includes the contaminants is formed in between the deposited layer and the substrate. Hydrogen atoms are introduced into the structure
Semiconductor Equipment and Materials International SEMI | Open Energy
Semiconductor Equipment and Materials International SEMI Semiconductor Equipment and Materials International SEMI Jump to: navigation, search Name Semiconductor Equipment and Materials International (SEMI) Place San Jose, California Zip 95134 2127 Product Global trade association, publisher and conference organiser representing the semiconductor and flat panel display equipment manufacturers. References Semiconductor Equipment and Materials International (SEMI)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Semiconductor Equipment and Materials International (SEMI) is a company located in San Jose, California . References ↑ "Semiconductor Equipment and Materials International (SEMI)" Retrieved from "http://en.openei.org/w/index.php?title=Semiconductor_Equipment_and_Materials_International_SEMI&oldid=350739
Furan Substituted Diketopyrrolopyrrole and Thienylenevinylene Based Low Band Gap Copolymer for High Mobility Organic Thin Film Transistors
A novel solution processable donor-acceptor (D-A) based low band gap polymer semiconductor poly{l_brace}3,6-difuran-2-yl-2,5-di(2-octyldodecyl)-pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thienylenevinylene{r_brace} (PDPPF-TVT), was designed and synthesized by a Pd-catalyzed Stille coupling route. An electron deficient furan based diketopyrrolopyrrole (DPP) block and electron rich thienylenevinylene (TVT) donor moiety were attached alternately in the polymer backbone. The polymer exhibited good solubility, film forming ability and thermal stability. The polymer exhibits wide absorption bands from 400 nm to 950 nm (UV-vis-NIR region) with absorption maximum centered at 782 nm in thin film. The optical band gap (E{sub g}{sup opt}) calculated from the polymer film absorption onset is around 1.37 eV. The {pi}-energy band level (ionization potential) calculated by photoelectron spectroscopy in air (PESA) for PDPPF-TVT is around 5.22 eV. AFM and TEM analyses of the polymer reveal nodular terrace morphology with optimized crystallinity after 200 C thermal annealing. This polymer exhibits p-channel charge transport characteristics when used as the active semiconductor in organic thin-film transistor (OTFT) devices. The highest hole mobility of 0.13 cm{sup 2} V{sup -1} s{sup -1} is achieved in bottom gate and top-contact OTFT devices with on/off ratios in the range of 10{sup 6}-10{sup 7}. This work reveals that the replacement of thiophene by furan in DPP copolymers exhibits such a high mobility, which makes DPP furan a promising block for making a wide range of promising polymer semiconductors for broad applications in organic electronics.
Sonar, Prashant [Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology, and Research; Zhuo, Jing-Mei [Department of Physics, National University of Singapore; Zhao, Li-Hong [National University of Singapore; Lim, Kai-Ming [Department of Physics, National University of Singapore; Chen, Jihua [ORNL; Rondinone, Adam Justin [ORNL; Singh, Samarendra [Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology, and Research; Chua, Lay-Lay [National University of Singapore; Ho, Peter [National University of Singapore; Dodabalapur, Ananth [National University of Singapore
The importance of intra-molecular electron spin relaxation in small molecular semiconductors
Electron spin relaxation rate (eSR) is investigated on several organic semiconductors of different morphologies and molecular structures, using avoided level crossing muon spectroscopy as a local spin probe. We find that two functionalized acenes (polycrystalline tri(isopropyl)silyl-pentacene and amorphous 5,6,11,12-tetraphenyltetracene) exhibit eSRs with an Arrhenius-like temperature dependence, each with two characteristic energy scales similar to those expected from vibrations. Polycrystalline tris(8-hydroxyquinolate)gallium shows a similar behavior. The observed eSR for these molecules is no greater than 0.85 MHz at 300 K. The variety of crystal structures and transport regimes that these molecules possess, as well as the local nature of the probe, strongly suggest an intra-molecular phenomenon general to many organic semiconductors, contrasting the commonly assumed spin relaxation models based on inter-molecular charge carrier transport.
L. Schulz; M. Willis; L. Nuccio; P. Shusharov; S. Fratini; F. L. Pratt; W. P. Gillin; T. Kreouzis; M. Heeney; N. Stingelin; C. A. Stafford; D. J. Beesley; C. Bernhard; J. E. Anthony; I. Mckenzie; J. S. Lord; A. J. Drew
Metal Oxide Semiconductor Nanoparticles Open the Door to ...
Using metal oxide semiconductor nanoparticles to target and control biological molecules could fuel medical breakthroughs in many areas, including ...
Growth of pseudomorphic structures through organic epitaxy
The control of molecular orientation in thin solid film phases of organic semiconductors is a basic factor for the exploitation of their physical properties for optoelectronic devices. We compare structural and optical properties of thin films of the organic semiconductor {alpha}-quarterthiophene grown by molecular beam epitaxy on different organic substrates. We show how epitactic interactions, characteristic of the surface of organic crystals, can drive the orientation of the crystalline overlayer and the selection of specific polymorphs and new pseudomorphic phases. We identify a key role in this phenomenon played by the marked groove-like corrugations present in some organic crystal surfaces. Since different polymorphs possess rather different performance in terms of, e.g., charge carrier mobility, this strategy is demonstrated to allow for the growth of oriented phases with enhanced physical properties, while keeping the substrate at room temperature. These results provide useful guidelines for the design of technological substrates for organic epitaxy and they substantiate the adoption of an organic epitaxy approach for the fabrication of optoelectronic devices based on thin films of organic semiconductors.
Kaviyil, Sreejith Embekkat; Sassella, Adele; Borghesi, Alessandro [Department of Materials Science, Universita degli Studi di Milano Bicocca, Via R. Cozzi 53, I-20125 Milan (Italy); Campione, Marcello [Department of Earth and Environmental Sciences, Universita degli Studi di Milano Bicocca, Piazza della Scienza 4, I-20126 Milan (Italy); Su Genbo; He Youping [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou 350002 (China); Chen Chenjia [Department of Physics, Peking University, Beijing 100871 (China)
Method of physical vapor deposition of metal oxides on semiconductors
A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.
Norton, David P. (Knoxville, TN)
Preparation of III-V semiconductor nanocrystals
Nanometer-scale crystals of III-V semiconductors are disclosed, They are prepared by reacting a group III metal source with a group V anion source in a liquid phase at elevated temperature in the presence of a crystallite growth terminator such as pyridine or quinoline.
Alivisatos, A. Paul (Berkeley, CA); Olshavsky, Michael A. (Brunswick, OH)
Optical temperature sensor using thermochromic semiconductors
Optical thermometry is a growing technological field which exploits the ability of certain materials to change their optical properties with temperature. A subclass of such materials are those which change their color as a reversible and reproducible function of temperature. These materials are thermochromic. This invention is a composition to measure temperature utilizing thermochromic semiconductors.
High resolution scintillation detector with semiconductor readout
A novel high resolution scintillation detector array for use in radiation imaging such as high resolution Positron Emission Tomography (PET) which comprises one or more parallelepiped crystals with at least one long surface of each crystal being in intimate contact with a semiconductor photodetector such that photons generated within each crystal by gamma radiation passing therethrough is detected by the photodetector paired therewith.
Levin, Craig S. (Santa Monica, CA); Hoffman, Edward J. (Los Angeles, CA)
Semiconductor diode with external field modulation
A non-destructive-readout nonvolatile semiconductor diode switching device that may be used as a memory element is disclosed. The diode switching device is formed with a ferroelectric material disposed above a rectifying junction to control the conduction characteristics therein by means of a remanent polarization. The invention may be used for the formation of integrated circuit memories for the storage of information.
Nasby, Robert D. (Albuquerque, NM)
Electrical Usage Characterization of Semiconductor Processing Tools
This paper presents the basic concepts in performing an energy and power audit of a semiconductor process tool. A protocol exists that fully describes these measurements and their use and applicability and it will be described. This protocol is currently being examined by SEMATECH for future publication. Example data will be presented showing the power, energy, and current load profiles of a typical tool.
Hinson, S. R.
Band anticrossing effects in highly mismatched semiconductor alloys
The first five chapters of this thesis focus on studies of band anticrossing (BAC) effects in highly electronegativity- mismatched semiconductor alloys. The concept of bandgap bowing has been used to describe the deviation of the alloy bandgap from a linear interpolation. Bowing parameters as large as 2.5 eV (for ZnSTe) and close to zero (for AlGaAs and ZnSSe) have been observed experimentally. Recent advances in thin film deposition techniques have allowed the growth of semiconductor alloys composed of significantly different constituents with ever- improving crystalline quality (e.g., GaAs{sub 1-x}N{sub x} and GaP{sub 1-x}N{sub x} with x {approx}< 0.05). These alloys exhibit many novel and interesting properties including, in particular, a giant bandgap bowing (bowing parameters > 14 eV). A band anticrossing model has been developed to explain these properties. The model shows that the predominant bowing mechanism in these systems is driven by the anticrossing interaction between the localized level associated with the minority component and the band states of the host. In this thesis I discuss my studies of the BAC effects in these highly mismatched semiconductors. It will be shown that the results of the physically intuitive BAC model can be derived from the Hamiltonian of the many-impurity Anderson model. The band restructuring caused by the BAC interaction is responsible for a series of experimental observations such as a large bandgap reduction, an enhancement of the electron effective mass, and a decrease in the pressure coefficient of the fundamental gap energy. Results of further experimental investigations of the optical properties of quantum wells based on these materials will be also presented. It will be shown that the BAC interaction occurs not only between localized states and conduction band states at the Brillouin zone center, but also exists over all of k-space. Finally, taking ZnSTe and ZnSeTe as examples, I show that BAC also occurs between localized states and the valence band states. Soft x-ray fluorescence experiments provide direct evidence of the BAC interaction in these systems. In the final chapter of the thesis, I describe and summarize my studies of optical properties of wurtzite InN and related alloys. Early studies performed on InN films grown by sputtering techniques suggested a direct bandgap of {approx}1.9 eV for this semiconductor. Very recently, high-quality InN films with much higher mobility have become available by using the molecular beam epitaxy growth method. Optical experiments carried out on these samples reveal a narrow bandgap for InN of 0.77 eV, much lower than the previously accepted value. Optical properties of InGaN and InAlN ternaries on the In rich side have also been characterized and are found to be consistent with the narrow bandgap of InN. The bandgap bowing parameters in these alloys were determined. In the context of these findings, the bandgap energies of InGaN and InAlN were found to cover a wide spectral range from the infrared for InN to the ultraviolet for GaN and deep ultraviolet for AlN. The significance of this work is rooted in many important applications of nitride semiconductors in optoelectronics and solar energy conversion devices.
Wu, Junqiao
Evaluation of Radiation Resistance for Organic Materials
carbide fiber Evaluation of semiconductor devices for space use Creation of carnations with variety Research Activities for Quantum Beam Applications Polymer electrolyte membrane for fuel cells Silicon for organic materials used in atomic energy- related facilities J-PARC ITER Si-polymer Forming : fiber
McDonald, Kirk
0001 0001 Transport and Kinetic Processes in GaN Epitaxial Lateral Overgrowth M. E. Coltrin and C. C. Mitchell Motivation-GaN is a wide band gap semi- conductor with a broad range of potential appli- cations, e.g., high-temperature electronics, op- telectronics, chemical or biological sensors. GaN thin films usually have a high defect den- sity, leading to poor performance. Epitaxial Lat- eral Overgrowth (ELO) has been shown to greatly reduce defect densities, often by factors of 100 or more. We are conducting fundamental studies of GaN growth kinetics during ELO. Accomplishment-In ELO, a mask pattern of dielectric material is deposited on top of a GaN buffer layer. Further growth of GaN occurs se- lectively on exposed areas of the underlying buffer layer, and not on the dielectric material.
A Spintronic Semiconductor with Selectable Charge Carriers
A Spintronic Semiconductor with Selectable Charge Carriers Print A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics, processing is done using semiconductor materials like silicon and germanium that have the requisite properties to perform logical operations with both electrons (negative n-type charge carriers) and holes (positive p-type charge carriers). Thus, a spintronically desirable semiconductor would simultaneously have discrete spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or on alloying, both of which have drawbacks such as chemical instability or reduced mobility. In BiTeI, however, electron and hole conduction is achieved without modifying the ideal crystal structure. One of the things discovered by Crepaldi et al. was that the electronic band structure of BiTeI bends in different ways near the surface depending on which layer is on top. That, in turn, means that the Fermi level (which determines a material's conductivity) can be located in either the valence band (for positive charge carriers) or the conduction band (for negative charge carriers). With techniques such as molecular-beam epitaxy and chemical vapor deposition, it is realistic to consider that regions with opposite band bending could be patterned on a substrate, opening new possibilities for the manipulation of spin-polarized states.
Semiconductor Laser Diode Pumps for Inertial Fusion Energy Lasers
Solid-state lasers have been demonstrated as attractive drivers for inertial confinement fusion on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) and at the Omega Facility at the Laboratory for Laser Energetics (LLE) in Rochester, NY. For power plant applications, these lasers must be pumped by semiconductor diode lasers to achieve the required laser system efficiency, repetition rate, and lifetime. Inertial fusion energy (IFE) power plants will require approximately 40-to-80 GW of peak pump power, and must operate efficiently and with high system availability for decades. These considerations lead to requirements on the efficiency, price, and production capacity of the semiconductor pump sources. This document provides a brief summary of these requirements, and how they can be met by a natural evolution of the current semiconductor laser industry. The detailed technical requirements described in this document flow down from a laser ampl9ifier design described elsewhere. In brief, laser amplifiers comprising multiple Nd:glass gain slabs are face-pumped by two planar diode arrays, each delivering 30 to 40 MW of peak power at 872 nm during a {approx} 200 {micro}s quasi-CW (QCW) pulse with a repetition rate in the range of 10 to 20 Hz. The baseline design of the diode array employs a 2D mosaic of submodules to facilitate manufacturing. As a baseline, they envision that each submodule is an array of vertically stacked, 1 cm wide, edge-emitting diode bars, an industry standard form factor. These stacks are mounted on a common backplane providing cooling and current drive. Stacks are conductively cooled to the backplane, to minimize both diode package cost and the number of fluid interconnects for improved reliability. While the baseline assessment in this document is based on edge-emitting devices, the amplifier design does not preclude future use of surface emitting diodes, which may offer appreciable future cost reductions and increased reliability. The high-level requirements on the semiconductor lasers involve reliability, price points on a price-per-Watt basis, and a set of technical requirements. The technical requirements for the amplifier design in reference 1 are discussed in detail and are summarized in Table 1. These values are still subject to changes as the overall laser system continues to be optimized. Since pump costs can be a significant fraction of the overall laser system cost, it is important to achieve sufficiently low price points for these components. At this time, the price target for tenth-of-akind IFE plant is $0.007/Watt for packaged devices. At this target level, the pumps account for approximately one third of the laser cost. The pump lasers should last for the life of the power plant, leading to a target component lifetime requirement of roughly 14 Ghosts, corresponding to a 30 year plant life and 15 Hz repetition rate. An attractive path forward involes pump operation at high output power levels, on a Watts-per-bar (Watts/chip) basis. This reduces the cost of pump power (price-per-Watt), since to first order the unit price does not increase with power/bar. The industry has seen a continual improvement in power output, with current 1 cm-wide bars emitting up to 500 W QCW (quasi-continuous wave). Increased power/bar also facilitates achieving high irradiance in the array plane. On the other hand, increased power implies greater heat loads and (possibly) higher current drive, which will require increased attention to thermal management and parasitic series resistance. Diode chips containing multiple p-n junctions and quantum wells (also called nanostack structures) may provide an additional approach to reduce the peak current.
Deri, R J
World Wide Web Information Servers
World Wide Web Information Servers World Wide Web Information Servers Lawrence Berkeley Laboratory recently announced a gopher and World Wide Web site. To get to the web site, telnet to www.lbl.gov, login: www. Access is provided to LBL's gopher, library catalog, and publication list. The Center is funding the implementation of a WWW network node for on-line access to publications, databases, and documents full of hypermedia links to other documents or information systems from the Energy & Environment Division. Full implementation is expected by May 1994, and will include access to a variety of information from all the research programs and centers. The technology transfer project calls for this newsletter to be published on WWW using the Mosaic interface under development at the National Center
Oxide Ferromagnetic Semiconductors for Spin-Electronic Transprt
The objective of this research was to investigate the viability of oxide magnetic semiconductors as potential materials for spintronics. We identified some members of the solid solution series of ilmenite (FeTiO3) and hematite (Fe2O3), abbreviated as (IH) for simplicity, for our investigations based on their ferromagnetic and semiconducting properties. With this objective in focus we limited our investigations to the following members of the modified Fe-titanates: IH33 (ilmenitehematite with 33 atomic percent hematite), IH45 (ilmenite-hematite with 45 atomic percent hematite), Mn-substituted ilmenite (Mn-FeTiO3), and Mn-substituted pseudobrookite (Mn- Fe2TiO5). All of them are: 1. wide bandgap semiconductors with band gaps ranging in values between 2.5 to 3.5 eV; 2. n-type semiconductors; 3.they exhibit well defined magnetic hysteresis loops and 4. their magnetic Curie points are greater than 400K. Ceramic, film and single crystal samples were studied and based on their properties we produced varistors (also known as voltage dependent resistors) for microelectronic circuit protection from power surges, three-terminal microelectronic devices capable of generating bipolar currents, and an integrated structured device with controlled magnetic switching of spins. Eleven refereed journal papers, three refereed conference papers and three invention disclosures resulted from our investigations. We also presented invited papers in three international conferences and one national conference. Furthermore two students graduated with Ph.D. degrees, three with M.S. degrees and one with B.S. degree. Also two post-doctoral fellows were actively involved in this research. We established the radiation hardness of our devices in collaboration with a colleague in an HBCU institution, at the Cyclotron Center at Texas A&M University, and at DOE National Labs (Los Alamos and Brookhaven). It is to be appreciated that we met most of our goals and expanded vastly the scope of research by including investigations of Mn-FeTiO3, Mn-Fe2TiO5 and by producing a novel three terminal device capable of generating bipolar currents besides producing radiation resistant varistors and a magnetically switchable device. Furthermore we conclusively established the radiation hardness of the four modified iron titanates we studied. In all our publications, conference and seminar presentations, dissertations and theses sponsorship of DOE has been acknowledged
Dr. R. K. Pandey, Cudworth Endowed Professor (Professor Emeritus of The Unviersity of Alabama) Ingram Endowed Professor, Ingram School of Engineering and Physics Department, Texas State University, San Marocs, TX78666
VENTILATION (HVAC) FAILURE (BUILDING WIDE) A failure or shutdown of the ventilation system will be signaled by cessation of the audible background "rumbling" sound of the building's HVAC system. As building durations. NOTE: Due to unpredictable pressure differentials in and around the labs during an HVAC failure
Strynadka, Natalie
Aspects of charge recombination and charge transport in organic solar cells and light-emitting devices
In this thesis, aspects of charge reconbination and charge transport in organic solar cells and light-emitting devices are presented. These devices show promise relative to traditional inorganic semiconductors. We show ...
Measurement and control of exciton spin in organic light emitting devices
Organic semiconductors are a promising new material set for electronic and optoelectronic devices. Their properties can be precisely controlled through chemistry, and they are well-suited for large-area, flexible, and ...
Segal, Michael, Ph. D. Massachusetts Institute of Technology
Physical properties and design of light-emitting devices based on organic materials and nanoparticles
This thesis presents the detailed experimental and theoretical characterization of light-emitting devices (LEDs) based on organic semiconductors and colloidal quantum dots (QDs). This hybrid material system has several ...
Anikeeva, Polina Olegovna
Isotopically engineered semiconductors: from the bulk tonanostructures
Research performed with semiconductors with controlled isotopic composition is evolving from the measurement of fundamental properties in the bulk to those measured in superlattices and nanostructures. This is driven in part by interests associated with the fields of 'spintronics' and quantum computing. In this topical review, which is dedicated to Prof. Abstreiter, we introduce the subject by reviewing classic and recent measurements of phonon frequencies, thermal conductivity, bandgap renormalizations, and spin coherence lifetimes in isotopically controlled bulk group IV semiconductors. Next, we review phonon properties measured in isotope heterostructures, including pioneering work made possible by superlattices grown by the group of Prof. Abstreiter. We close the review with an outlook on the exciting future possibilities offered through isotope control in 1, 2, and 3 dimensions that will be possible due to advances in nanoscience.
Ager III, Joel W.; Haller, Eugene E.
Proximity charge sensing for semiconductor detectors
A non-contact charge sensor includes a semiconductor detector having a first surface and an opposing second surface. The detector includes a high resistivity electrode layer on the first surface and a low resistivity electrode on the high resistivity electrode layer. A portion of the low resistivity first surface electrode is deleted to expose the high resistivity electrode layer in a portion of the area. A low resistivity electrode layer is disposed on the second surface of the semiconductor detector. A voltage applied between the first surface low resistivity electrode and the second surface low resistivity electrode causes a free charge to drift toward the first or second surface according to a polarity of the free charge and the voltage. A charge sensitive preamplifier coupled to a non-contact electrode disposed at a distance from the exposed high resistivity electrode layer outputs a signal in response to movement of free charge within the detector.
Luke, Paul N; Tindall, Craig S; Amman, Mark
Semiconductor P-I-N detector
A semiconductor P-I-N detector including an intrinsic wafer, a P-doped layer, an N-doped layer, and a boundary layer for reducing the diffusion of dopants into the intrinsic wafer. The boundary layer is positioned between one of the doped regions and the intrinsic wafer. The intrinsic wafer can be composed of CdZnTe or CdTe, the P-doped layer can be composed of ZnTe doped with copper, and the N-doped layer can be composed of CdS doped with indium. The boundary layers is formed of an undoped semiconductor material. The boundary layer can be deposited onto the underlying intrinsic wafer. The doped regions are then typically formed by a deposition process or by doping a section of the deposited boundary layer.
Sudharsanan, Rengarajan (53 Timber Line Dr., Nashua, NH 03062); Karam, Nasser H. (577 Lowell St., Lexington, MA 02173)
Semiconductor Manufacturing International Corp SMIC | Open Energy
Manufacturing International Corp SMIC Manufacturing International Corp SMIC Jump to: navigation, search Name Semiconductor Manufacturing International Corp (SMIC) Place Shanghai, Shanghai Municipality, China Zip 201203 Sector Solar Product Semiconductor group launching solar cell production from its recycled silicon wafers. Coordinates 31.247709°, 121.472618° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":31.247709,"lon":121.472618,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
GaTe semiconductor for radiation detection
GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.
Payne, Stephen A. (Castro Valley, CA); Burger, Arnold (Nashville, TN); Mandal, Krishna C. (Ashland, MA)
Semiconductor junction formation by directed heat
The process of the invention includes applying precursors 6 with N- and P-type dopants therein to a silicon web 2, with the web 2 then being baked in an oven 10 to drive off excessive solvents, and the web 2 is then heated using a pulsed high intensity light in a mechanism 12 at 1100.degree.-1150.degree. C. for about 10 seconds to simultaneously form semiconductor junctions in both faces of the web.
Campbell, Robert B. (Pittsburgh, PA)
Fuzzy Logic Connectivity in Semiconductor Defect Clustering
In joining defects on semiconductor wafer maps into clusters, it is common for defects caused by different sources to overlap. Simple morphological image processing tends to either join too many unrelated defects together or not enough together. Expert semiconductor fabrication engineers have demonstrated that they can easily group clusters of defects from a common manufacturing problem source into a single signature. Capturing this thought process is ideally suited for fuzzy logic. A system of rules was developed to join disconnected clusters based on properties such as elongation, orientation, and distance. The clusters are evaluated on a pair-wise basis using the fuzzy rules and are joined or not joined based on a defuzzification and threshold. The system continuously re-evaluates the clusters under consideration as their fuzzy memberships change with each joining action. The fuzzy membership functions for each pair-wise feature, the techniques used to measure the features, and methods for improving the speed of the system are all developed. Examples of the process are shown using real-world semiconductor wafer maps obtained from chip manufacturers. The algorithm is utilized in the Spatial Signature Analyzer (SSA) software, a joint development project between Oak Ridge National Lab (ORNL) and SEMATECH.
Gleason, S.S.; Kamowski, T.P.; Tobin, K.W.
Visible-wavelength semiconductor lasers and arrays
A visible semiconductor laser. The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1.lambda.) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%.
Schneider, Jr., Richard P. (Albuquerque, NM); Crawford, Mary H. (Albuquerque, NM)
Hybrid Solar Cells with Prescribed Nanoscale Morphologies Based onHyperbranched Semiconductor Nanocrystals
In recent years, the search to develop large-area solar cells at low cost has led to research on photovoltaic (PV) systems based on nanocomposites containing conjugated polymers. These composite films can be synthesized and processed at lower costs and with greater versatility than the solid state inorganic semiconductors that comprise today's solar cells. However, the best nanocomposite solar cells are based on a complex architecture, consisting of a fine blend of interpenetrating and percolating donor and acceptor materials. Cell performance is strongly dependent on blend morphology, and solution-based fabrication techniques often result in uncontrolled and irreproducible blends, whose composite morphologies are difficult to characterize accurately. Here we incorporate 3-dimensional hyper-branched colloidal semiconductor nanocrystals in solution-processed hybrid organic-inorganic solar cells, yielding reproducible and controlled nanoscale morphology.
Gur, Ilan; Fromer, Neil A.; Chen, Chih-Ping; Kanaras, AntoniosG.; Alivisatos, A. Paul
Climate VISION: Private Sector Initiatives: Semiconductors: Resources and
Semiconductor Industry Association (SIA) The Semiconductor Industry Association (SIA) is the premier trade association representing the U.S. semiconductor industry. Founded in 1977 by five microelectronics innovators, the SIA has grown to include over 100 companies that account for more than 83% of U.S.-based semiconductor production. The SIA provides a forum for domestic semiconductor companies to work collectively to advance the competitiveness of the $70 billion U.S. chip industry. Through its national and international network of chief executive officers and working committees, the SIA shapes public policy on issues important to the industry and provides a spectrum of services to help its members grow their businesses. World Semiconductor Council (WSC)
Semiconductor and Materials Company Inc SAMCO | Open Energy Information
and Materials Company Inc SAMCO and Materials Company Inc SAMCO Jump to: navigation, search Name Semiconductor and Materials Company Inc (SAMCO) Place Kyoto, Kyoto, Japan Zip 612-8443 Sector Solar Product Japanese manufactruer of semiconductor and solar manufacturing equipment such as etching, deposition and cleaning systems. References Semiconductor and Materials Company Inc (SAMCO)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Semiconductor and Materials Company Inc (SAMCO) is a company located in Kyoto, Kyoto, Japan . References ↑ "Semiconductor and Materials Company Inc (SAMCO)" Retrieved from "http://en.openei.org/w/index.php?title=Semiconductor_and_Materials_Company_Inc_SAMCO&oldid=350738
Gallium-Nitride Transistors for High-Efficiency Industrial Power Supplies, Phase 1: State of Semiconductor Development and Industrial Power Supply Market
This white paper describes recent advancements in the development of Gallium-Nitride (GaN) transistors for power conversion applications. This wide bandgap semiconductor has the potential to reduce losses and improve performance of power converters. The industrial power supply market is described and the application of GaN to power conversion in this segment is introduced for future work.
Guiding effect of quantum wells in semiconductor lasers
The guiding effect of InGaAs quantum wells in GaAs- and InP-based semiconductor lasers has been studied theoretically and experimentally. The results demonstrate that such waveguides can be effectively used in laser structures with a large refractive index difference between the quantum well material and semiconductor matrix and a large number of quantum wells (e.g. in InP-based structures). (semiconductor lasers. physics and technology)
Aleshkin, V Ya; Dikareva, Natalia V; Dubinov, A A; Zvonkov, B N; Karzanova, Maria V; Kudryavtsev, K E; Nekorkin, S M; Yablonskii, A N
Graded core/shell semiconductor nanorods and nanorod barcodes
Graded core/shell semiconductor nanorods and shaped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.
Alivisatos, A. Paul (Oakland, CA); Scher, Erik C. (San Francisco, CA); Manna, Liberato (Lecce, IT)
Graded core/shell semiconductor nanorods and shapped nanorods are disclosed comprising Group II-VI, Group III-V and Group IV semiconductors and methods of making the same. Also disclosed are nanorod barcodes using core/shell nanorods where the core is a semiconductor or metal material, and with or without a shell. Methods of labeling analytes using the nanorod barcodes are also disclosed.
Alivisatos, A. Paul; Scher, Erik C.; Manna, Liberato
Controlled growth of larger heterojunction interface area for organic photosensitive devices
An optoelectronic device and a method of fabricating a photosensitive optoelectronic device includes depositing a first organic semiconductor material on a first electrode to form a continuous first layer having protrusions, a side of the first layer opposite the first electrode having a surface area at least three times greater than an underlying lateral cross-sectional area; depositing a second organic semiconductor material directly on the first layer to form a discontinuous second layer, portions of the first layer remaining exposed; depositing a third organic semiconductor material directly on the second layer to form a discontinuous third layer, portions of at least the second layer remaining exposed; depositing a fourth organic semiconductor material on the third layer to form a continuous fourth layer, filling any exposed gaps and recesses in the first, second, and third layers; and depositing a second electrode on the fourth layer, wherein at least one of the first electrode and the second electrode is transparent, and the first and third organic semiconductor materials are both of a donor-type or an acceptor-type relative to second and fourth organic semiconductor materials, which are of the other material type.
Yang, Fan (Somerset, NJ); Forrest, Stephen R. (Ann Arbor, MI)
Photophysics of Two-dimensional Semiconductor Nanoparticle/Liquid Interfaces
These studies have investigated the optical properties of two very different types of two-dimensional semiconductor nanoclusters and superlattices of these nanoclusters.
Kelley, David F.
Understanding How Semiconductors Absorb Light | U.S. DOE Office...
Understanding How Semiconductors Absorb Light Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy...
Strain tuning of topological band order in cubic semiconductors
We theoretically explore the possibility of tuning the topological order of cubic diamond/zinc-blende semi- conductors with external strain. Based on a simple tight-binding model, we analyze the evolution of the cubic semiconductor band structure under hydrostatic or biaxial lattice expansion, by which a generic guiding princi- ple is established that biaxial lattice expansion can induce a topological phase transition of small band-gap cubic semiconductors via a band inversion and symmetry breaking at point. Using density functional theory cal- culations, we demonstrate that a prototype topological trivial semiconductor, InSb, is converted to a nontrivial topological semiconductor with a 2% 3% biaxial lattice expansion.
Feng, wanxiang [Chinese Academy of Sciences; Zhu, Wenguang [University of Tennessee, Knoxville (UTK); Weitering, Hanno [University of Tennessee, Knoxville (UTK); Stocks, George Malcolm [ORNL; Yao, yugui [Chinese Academy of Sciences; Xiao, Di [ORNL
Resonator for Coherent Addition of Semiconductor Laser Arrays ...
Resonator for Coherent Addition of Semiconductor Laser Arrays and Applications for a Solar Pumped Laser Array Oak Ridge National Laboratory. Contact ...
Method for depositing high-quality microcrystalline semiconductor materials
A process for the plasma deposition of a layer of a microcrystalline semiconductor material is carried out by energizing a process gas which includes a precursor of the semiconductor material and a diluent with electromagnetic energy so as to create a plasma therefrom. The plasma deposits a layer of the microcrystalline semiconductor material onto the substrate. The concentration of the diluent in the process gas is varied as a function of the thickness of the layer of microcrystalline semiconductor material which has been deposited. Also disclosed is the use of the process for the preparation of an N-I-P type photovoltaic device.
Guha, Subhendu (Bloomfield Hills, MI); Yang, Chi C. (Troy, MI); Yan, Baojie (Rochester Hills, MI)
Production of 35S for a Liquid Semiconductor Betavoltaic
The specific energy density from radioactive decay is five to six orders of magnitude greater than the specific energy density in conventional chemical battery and fuel cell technologies. We are currently investigating the use of liquid semiconductor based betavoltaics as a way to directly convert the energy of radioactive decay into electrical power and potentially avoid the radiation damage that occurs in solid state semiconductor devices due to non-ionizing energy loss. Sulfur-35 was selected as the isotope for the liquid semiconductor demonstrations because it can be produced in high specific activity and it is chemically compatible with known liquid semiconductor media.
Meier, David E.; Garnov, A. Y.; Robertson, J. D.; Kwon, J. W.; Wacharasindhu, T.
Argonne CNM News: HMapping Deformation in Buried Semiconductor...
CMOS performance. Nano-XRD allows for the first time in situ nanoscale mapping of lattice strain and tilt within a buried semiconductor layer at high spatial resolution...
Metal Oxide Semiconductor Nanoparticles Pave the Way for ...
Argonne researchers have developed a unique application of technology that involves using metal oxide semiconductor nanoparticles to target and control biological ...
Technical Information Technical Information Download Acrobat Reader Modeling China's Semiconductor Industry Fluorinated Compound Emissions and Drafting a Roadmap for Climate Protection. (PDF 101 KB) 14th Annual International Semiconductor Environment Safety & Health (ISESH) Conference in Jeju, Korea (June 2007) presentation by Scott Bartos, U.S. EPA. Estimating the Impact of Migration to Asian Foundry Production on Attaining the WSC 2010 PFC Reduction Goal. (PDF 458 KB) 11th Annual ISESH Conference in Makuhari, Japan (July 2004) presentation by Scott Bartos, U.S. EPA. Guidelines for Environmental Characterization of Semiconductor Equipment (PDF 361 KB) This document provides guidelines for suppliers of semiconductor processing and abatement equipment to characterize their equipment to meet
July 28, 2010, Guiding semiconductor research through collaborative engagement
The SRC ... The SRC ... Guiding semiconductor research through collaborative engagement Elizabeth J. Weitzman Exec. VP, SRC Exec. Director, Focus Center Research Program Semiconductor Research Corporation 2 ... Awarded Nat'l Medal of Technology Presidential Citation: "For building the world's largest and most successful university research force to support the ... semiconductor industry; For proving the concept of collaborative research as the first high-tech research consortium; and For creating the concept and methodology that evolved into the International Technology Roadmap for Semiconductors." 3 Key Attributes of SRC Research Entities 1. Accepted IP model. SRC's model has been
MST: Organizations: Organic Materials
Adhesive Bonding Adhesive Bonding Composites Encapsulation Materials Characterization Mechanical Testing Molding, Thermoforming, & Compounding Organizations Organic Materials Composite-to-metal adhesive bond Experimental/analytical study of composit-to-metal adhesive bond. The Organic Materials department in the Advanced Manufacturing and Processing Laboratory provides innovative prototype fabrication, full service small lot production, materials technology, processing expertise, and a broad range of organic material characterization and mechanical testing techniques. We encapsulate, we join and bond, we foam, we analyze and image, we build composite structures. We strive to make you, our customers, successful! We partner with you to find the right combination of materials, processing, and fixturing that will result in the highest value
Organization | Department of Energy
Organization Organization Organization View Office of Management Organization Chart in PDF format. Office of Resource Management and Planning The Office of Resource Management and Planning provides the leadership and centralized management and direction of the Office of Management (MA) planning, budgeting, financial, human resources, and program execution processes; ensures that these processes are effective, and fully integrated and consistent with the Department-wide processes and requirements. Office of Aviation Management The Department of Energy, Aviation Program is the management function for all fleet aircraft and contracted aviation services for the Department. The program and its management personnel operate world-wide. To take advantage of the best communications and information services available, we have
Fully Integrated Complementary Metal Oxide Semiconductor (CMOS) Bio-Assay Platform
Oxide Semiconductor (CMOS) Bio-Assay Platform by OctavianOxide Semiconductor (CMOS) Bio-Assay Platform by OctavianOxide Semiconductor (CMOS) Bio-Assay Platform by Octavian
Florescu, Octavian
Environmental Resources on the World Wide Web
site is a directory to more than 350 organizations concerneddirectory called The Environmental Guidebook, which profiles nearly 500 key organizations
Shrode, Flora
GaAs photoconductive semiconductor switch
A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices.
Loubriel, Guillermo M. (Sandia Park, NM); Baca, Albert G. (Albuquerque, NM); Zutavern, Fred J. (Albuquerque, NM)
III-Nitride Semiconductors for Photovoltaic Applications
Using a band-structure method that includes bandgap correction, we study the chemical trends of the bandgap variation in III-V semiconductors and predict that the bandgap for InN is 0.85 0.1 eV. This result suggests that InN and its III-nitride alloys are suitable for photovoltaic applications. The unusually small bandgap for InN is explained in terms of the atomic energies and the bandgap deformation potentials. The electronic and structural properties of the nitrides and their alloys are also provided.
Wei, S. H.
Photocatalytic semiconductor clusters for fuel production
High quality crystalline, monodisperse nanometer-size semiconductor clusters were successfully grown using an inverse micellar synthesis process and their optical and structural properties were studied. Among the materials studied were PbS, FeS{sub 2}, MoS{sub 2}, CdS and related compounds. The results demonstrated strong electronic quantum confinement effects and broad tailorability of the bandgaps with decreasing cluster size, features that are important for the potential use of these materials as photocatalysts for solar fuel production and solar detoxification. The highlights of the work are included in an Executive Summary.
Wilcoxon, J.P.; Bliss, D.E.; Martin, J.E. [and others
Interesting Electronic and Dynamic Properties of Quantum Dot Quantum Wells and other Semiconductor Nanocrystal Heterostructures .
??Some interesting electronic and dynamic properties of semiconductor nanocrystal heterostructures have been investigated using various spectroscopic methods. Semiconductor nanocrystal heterostructures were prepared using colloidal synthesis� (more)
Schill, Alexander Wilhem
Dilute magnetic semiconductors in spin-polarized electronics (invited)
Dilute magnetic semiconductors have proven to be very useful in building an all-semiconductor platform for spintronics{emdash}so far they provide the only viable route to establish spin-polarized current injection into a nonmagnetic semiconductor. The reasons for this become apparent from a simple spin-channel model, which predicts that spin injection into a semiconductor can, within linear response, only readily be achieved from a ferromagnetic injector that has: (i) a resistivity that is comparable to the semiconductor and (ii) preferably is 100% spin polarized. Both of these criteria can be met in magnetic semiconductors, but (so far) are hard to achieve using other materials. Experimentally, we demonstrate how dilute magnetic II{endash}VI semiconductors can be used to inject a strongly (up to 90%) spin-polarized current into a light emitting diode. In addition, we discuss the implications of the spin-channel model for the observation of giant magnetoresistance-like effects in the magnetoresistance of an all-semiconductor device. {copyright} 2001 American Institute of Physics.
Schmidt, Georg; Molenkamp, Laurens W.
Study on Water-Cooled Solar Semiconductor Air Conditioner
Water-cooled solar semiconductor air conditioner was designed. Relevant calculation was made to determine the room's cooling load, which export the solar panels and battery capacity, followed by selection of CNC matcher. Development work also involves ... Keywords: solar energy, peltier effect, semiconductor air conditioner
Dong Zhi-Ming; Chang Ji-Bin; Xiang Li-Juan; Zhou Xue-Bin
Semiconductor device design using the BiMADS algorithm
Designing high-performance semiconductor devices is a complex optimization problem, which is characterized by multiple and, often, conflicting objectives. In this research work, we introduce a multi-objective optimization design approach based on the ... Keywords: Diodes, Drift-diffusion, Energy-transport, MESFETs, MOSFETs, Optimization, Semiconductors
Giovanni Stracquadanio, Vittorio Romano, Giuseppe Nicosia
The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1{lambda}) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%. 5 figs.
Schneider, R.P. Jr.; Crawford, M.H.
Coated semiconductor devices for neutron detection
A device for detecting neutrons includes a semi-insulated bulk semiconductor substrate having opposed polished surfaces. A blocking Schottky contact comprised of a series of metals such as Ti, Pt, Au, Ge, Pd, and Ni is formed on a first polished surface of the semiconductor substrate, while a low resistivity ("ohmic") contact comprised of metals such as Au, Ge, and Ni is formed on a second, opposed polished surface of the substrate. In one embodiment, n-type low resistivity pinout contacts comprised of an Au/Ge based eutectic alloy or multi-layered Pd/Ge/Ti/Au are also formed on the opposed polished surfaces and in contact with the Schottky and ohmic contacts. Disposed on the Schottky contact is a neutron reactive film, or coating, for detecting neutrons. The coating is comprised of a hydrogen rich polymer, such as a polyolefin or paraffin; lithium or lithium fluoride; or a heavy metal fissionable material. By varying the coating thickness and electrical settings, neutrons at specific energies can be detected. The coated neutron detector is capable of performing real-time neutron radiography in high gamma fields, digital fast neutron radiography, fissile material identification, and basic neutron detection particularly in high radiation fields.
Klann, Raymond T. (Bolingbrook, IL); McGregor, Douglas S. (Whitmore Lake, MI)
Photonic switching devices based on semiconductor nanostructures
Squeezing and guiding light into semiconductor nanostructures delivers revolutionary concepts of photonic devices, which may offer a practical pathway towards power-efficient optical networks. In this review, we consider photonic switches using semiconductor quantum dots (QDs) and photonic cavities. By intuitively introducing in a field enhancement factor, the optical nonlinearity of nano-photonic switches can be understood and this has shown their unique features to dramatically improve the power-density/speed limitation that has lain in conventional photonic switches for decades. In addition, the power consumption has been reduced due to the atom-like characterization of QDs as well as the nano-size footprint of photonic cavities. Based on this theoretical perspective, the current progress of QD/cavity switches is reviewed in terms of various optical nonlinearities which have been employed to demonstrate photonic switching at the nanoscale. Emerging functionalities enabled by cavity nonlinear effects such as the wavelength tuning and Purcell-factor tuning have been further introduced.
Chao-Yuan Jin; Osamu Wada
Distributed Quantum Computation Architecture Using Semiconductor Nanophotonics
In a large-scale quantum computer, the cost of communications will dominate the performance and resource requirements, place many severe demands on the technology, and constrain the architecture. Unfortunately, fault-tolerant computers based entirely on photons with probabilistic gates, though equipped with "built-in" communication, have very large resource overheads; likewise, computers with reliable probabilistic gates between photons or quantum memories may lack sufficient communication resources in the presence of realistic optical losses. Here, we consider a compromise architecture, in which semiconductor spin qubits are coupled by bright laser pulses through nanophotonic waveguides and cavities using a combination of frequent probabilistic and sparse determinstic entanglement mechanisms. The large photonic resource requirements incurred by the use of probabilistic gates for quantum communication are mitigated in part by the potential high-speed operation of the semiconductor nanophotonic hardware. The system employs topological cluster-state quantum error correction for achieving fault-tolerance. Our results suggest that such an architecture/technology combination has the potential to scale to a system capable of attacking classically intractable computational problems.
Rodney Van Meter; Thaddeus D. Ladd; Austin G. Fowler; Yoshihisa Yamamoto
Microbially Mediated Method for Making Semiconductor Nanoparticles
or quantum dot nanoparticles, are increasingly used in a wide range of electronics, including LED displays, solar cells, and medical imaging.
Elements of Doping Engineering in Semiconductors
Using defect thermodynamics, we discuss physical factors that affect doping limits in semiconductors. The dependencies of the defect formation enthalpy on the atomic chemical potentials and on the electron Fermi energy are demonstrated. These dependencies, in particular on the Fermi energy, lead to spontaneous formation of charge-compensating defects that can limit doping. Experimental data compiled for III-V, II-VI, and I-III-VI2 compounds support this view and further provide insight into the connections among different host materials. We argue that what matters is not the magnitude of the band gap that determines the dopability of a material, but rather, the relative position of the conduction-band minimum (in the case of n-doping) and the valence-band maximum (in the case of p-doping) with respect to vacuum.
Zhang, S. B.; Wei, S.; Zunger, A.
Internal cooling in a semiconductor laser diode
Abstract�A thermal model of a diode laser structure is developed which includes a bipolar thermoelectric term not included in previous models. It is shown that heterostructure band offsets can be chosen so that there are thermoelectric cooling sources near the active region; this method of cooling is internal to the device itself, as opposed to temperature stabilization schemes which employ an external cooler. A novel laser structure is proposed that is capable of internal cooling in the Ga1 In As Sb1 �GaSb material system with = 2 64 m. Index Terms�Electrothermal effects, lasers, laser thermal factors, photothermal effects, semiconductor lasers, thermionic emission, thermionic energy conversion, thermoelectric devices, thermoelectric energy conversion, thermoelectricity. Fig. 1. Band structure and thermoelectric heat source distribution for (a) and (b) conventional SCH, and (c) and (d) ICICLE.
K. P. Pipe; R. J. Ram; A. Shakouri
Exciton binding energy in semiconductor quantum dots
In the adiabatic approximation in the context of the modified effective mass approach, in which the reduced exciton effective mass {mu} = {mu}(a) is a function of the radius a of the semiconductor quantum dot, an expression for the exciton binding energy E{sub ex}(a) in the quantum dot is derived. It is found that, in the CdSe and CdS quantum dots with the radii a comparable to the Bohr exciton radii a{sub ex}, the exciton binding energy E{sub ex}(a) is substantially (respectively, 7.4 and 4.5 times) higher than the exciton binding energy in the CdSe and CdS single crystals.
Pokutnii, S. I., E-mail: firstname.lastname@example.com [National Academy of Sciences of Ukraine, G.V. Kurdjumov Institute for Metal Physics (Ukraine)
Ion Trap in a Semiconductor Chip
The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ion. Work on miniaturizing electromagnetic traps to the micrometer scale promises even higher levels of control and reliability. Compared with 'chip traps' for confining neutral atoms, ion traps with similar dimensions and power dissipation offer much higher confinement forces and allow unparalleled control at the single-atom level. Moreover, ion microtraps are of great interest in the development of miniature mass spectrometer arrays, compact atomic clocks, and most notably, large scale quantum information processors. Here we report the operation of a micrometer-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. We confine, laser cool, and measure heating of a single 111Cd+ ion in an integrated radiofrequency trap etched from a doped gallium arsenide (GaAs) heterostructure.
D. Stick; W. K. Hensinger; S. Olmschenk; M. J. Madsen; K. Schwab; C. Monroe
Hybrid Semiconductors for Hardier Electronics and Optoelectronics? |
Unveiling the Molecular Structure of the Target of Many Drugs Unveiling the Molecular Structure of the Target of Many Drugs A New Scenario for First Life on Earth Surface Orbital 'Roughness' in Colossal Magnetoresistive Oxide Different Roads Toward Quantum Criticality Orbital Reconstruction at a Complex Oxide Interface Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed Hybrid Semiconductors for Hardier Electronics and Optoelectronics? DECEMBER 21, 2007 Bookmark and Share The crystal structure of β-ZnTe(en)0:5, determined by single-crystal x-ray diffraction. Two-monolayerthick ZnTe slabs are interconnected by ethylenediamine (C2N2H8) molecules bonded to zinc atoms. Zn-Green, Te-Red, N-Blue,and C-Gray. Hydrogen atoms are omitted for clarity.
Organization Chart
and Mission Organization Staff - Organization Chart About Us Bob Cottingham, 865-241-0554 Computational Biology and Bioinformatics Meghan Drake 865-241-8288 Michael...
Science Organizations
Organizations Science Organizations National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place...
Equipment Reliability Site-Wide Training v1.0
The Equipment Reliability Site-Wide Training is a computer based training module that allows users to access training when desired and review it at their own pace. It provides graphics and interactive features to enhance learning. This training will support EPRInuclear utility members by raising awareness of personnel in various organizations as to their roles and responsibilities related to equipment reliability and focus attention on critical components and single point vulnerabilities within nuclear p...
Directory lists information, addresses, and phone numbers for 2,600 international, national, and regional organizations,organizations. Free software facilitates management of bibliographies, organizational and expertise directories,
Ultra wide-bandwidth micro energy harvester
An ultra wide-bandwidth resonating thin film PZT MEMS energy harvester has been designed, modeled, fabricated and tested. It harvests energy from parasitic ambient vibration at a wide range of amplitude and frequency via ...
Hajati, Arman
Spin Splitting and Spin Current in Strained Bulk Semiconductors
We present a theory for two recent experiments in bulk strained semiconductors and show that a new, previously overlooked, strain spin-orbit coupling term may play a fundamental role. We propose simple experiments that could clarify the origin of strain-induced spin-orbit coupling terms in inversion asymmetric semiconductors. We predict that a uniform magnetization parallel to the electric field will be induced in the samples studied in for specific directions of the applied electric field. We also propose special geometries to detect spin currents in strained semiconductors.
Bernevig, B.Andrei; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.
Inference of gene regulatory networks from genome-wide knockout fitness data
Motivation: Genome-wide fitness is an emerging type of high-throughput biological data generated for individual organisms by creating libraries of knockouts, subjecting them to broad ranges of environmental conditions, and measuring the resulting ...
Liming Wang, Xiaodong Wang, Adam P. Arkin, Michael S. Samoilov
Equipment Reliability Site-Wide Training - Korean Release (ER Site-Wide Training - Korean Release) 1.0
Equipment Reliability Site-Wide Training is a computer based training module that allows users to access training when desired and review it at their own pace. It provides graphics and interactive features to enhance learning. This training will support EPRInuclear utility members by raising awareness of personnel in various organizations as to their roles and responsibilities related to equipment reliability and focus attention on critical components and single point vulnerabilities within nuclear power...
Synthesis and Manipulation of Semiconductor Nanocrystals inMicrofluidic Reactors
Microfluidic reactors are investigated as a mechanism tocontrol the growth of semiconductor nanocrystals and characterize thestructural evolution of colloidal quantum dots. Due to their shortdiffusion lengths, low thermal masses, and predictable fluid dynamics,microfluidic devices can be used to quickly and reproducibly alterreaction conditions such as concentration, temperature, and reactiontime, while allowing for rapid reagent mixing and productcharacterization. These features are particularly useful for colloidalnanocrystal reactions, which scale poorly and are difficult to controland characterize in bulk fluids. To demonstrate the capabilities ofnanoparticle microreactors, a size series of spherical CdSe nanocrystalswas synthesized at high temperature in a continuous-flow, microfabricatedglass reactor. Nanocrystal diameters are reproducibly controlled bysystematically altering reaction parameters such as the temperature,concentration, and reaction time. Microreactors with finer control overtemperature and reagent mixing were designed to synthesize nanoparticlesof different shapes, such as rods, tetrapods, and hollow shells. The twomajor challenges observed with continuous flow reactors are thedeposition of particles on channel walls and the broad distribution ofresidence times that result from laminar flow. To alleviate theseproblems, I designed and fabricated liquid-liquid segmented flowmicroreactors in which the reaction precursors are encapsulated inflowing droplets suspended in an immiscible carrier fluid. The synthesisof CdSe nanocrystals in such microreactors exhibited reduced depositionand residence time distributions while enabling the rapid screening aseries of samples isolated in nL droplets. Microfluidic reactors werealso designed to modify the composition of existing nanocrystals andcharacterize the kinetics of such reactions. The millisecond kinetics ofthe CdSe-to-Ag2Se nanocrystal cation exchange reaction are measured insitu with micro-X-ray Absorption Spectroscopy in silicon microreactorsspecifically designed for rapid mixing and time-resolved X-rayspectroscopy. These results demonstrate that microreactors are valuablefor controlling and characterizing a wide range of reactions in nLvolumes even when nanoscale particles, high temperatures, causticreagents, and rapid time scales are involved. These experiments providethe foundation for future microfluidic investigations into the mechanismsof nanocrystal growth, crystal phase evolution, and heterostructureassembly.
Chan, Emory Ming-Yue
directory of sustainable building professionals, created and maintained by Sustainable Sources , an organization
Structure and growth morphology of an archetypal system for organic epitaxy: PTCDA on Ag,,111... B. Krause,1
.10.Aj, 61.66.Hq I. INTRODUCTION Over the last few years, organic semiconductors have ex- periencedStructure and growth morphology of an archetypal system for organic epitaxy: PTCDA on Ag,,111... B; revised manuscript received 24 July 2002; published 10 December 2002 The planar organic molecule 3
Schreiber, Frank
About Us Organization Organization Leadership Organization History Careers Contact Us Organization...
Ramgraber Semiconductor Equipment GmbH | Open Energy Information
Ramgraber Semiconductor Equipment GmbH Ramgraber Semiconductor Equipment GmbH Jump to: navigation, search Name Ramgraber Semiconductor Equipment GmbH Place Brunnthal, Germany Zip 85649 Sector Solar Product Makes semiconductor processing equipment, including solar cell manufacturing lines. Coordinates 48.006898°, 11.684687° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":48.006898,"lon":11.684687,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Argonne licenses diamond semiconductor discoveries to AKHAN Technologies |
licenses diamond semiconductor discoveries to AKHAN Technologies licenses diamond semiconductor discoveries to AKHAN Technologies By Joseph Bernstein * By Jared Sagoff * March 4, 2013 Tweet EmailPrint LEMONT, Ill. - The U.S. Department of Energy's Argonne National Laboratory announced today that the laboratory has granted AKHAN Technologies exclusive diamond semiconductor application licensing rights to breakthrough low-temperature diamond deposition technology developed by Argonne's Center for Nanoscale Materials (CNM). The Argonne-developed technology allows for the deposition of nanocrystalline diamond on a variety of wafer substrate materials at temperatures as low as 400 degrees Celsius. The combination of the Argonne's low-temperature diamond technology with AKHAN's Miraj Diamond(tm) process represents the state of the art in diamond semiconductor
Improving reuse of semiconductor equipment through benchmarking, standardization, and automation
The 6D program at Intel� Corporation was set up to improve operations around capital equipment reuse, primarily in their semiconductor manufacturing facilities. The company was faced with a number of challenges, including ...
Silber, Jacob B. (Jacob Bradley)
Business Case Slide 26: High-Value: Semiconductors - Description...
(cont.) Previous Slide Next Slide Table of Contents High-Value: Semiconductors - Description (cont.) Measuring the photo-voltaic properties of a DUO2 diode at NREL Measuring the...
Conductive layer for biaxially oriented semiconductor film growth
A conductive layer for biaxially oriented semiconductor film growth and a thin film semiconductor structure such as, for example, a photodetector, a photovoltaic cell, or a light emitting diode (LED) that includes a crystallographically oriented semiconducting film disposed on the conductive layer. The thin film semiconductor structure includes: a substrate; a first electrode deposited on the substrate; and a semiconducting layer epitaxially deposited on the first electrode. The first electrode includes a template layer deposited on the substrate and a buffer layer epitaxially deposited on the template layer. The template layer includes a first metal nitride that is electrically conductive and has a rock salt crystal structure, and the buffer layer includes a second metal nitride that is electrically conductive. The semiconducting layer is epitaxially deposited on the buffer layer. A method of making such a thin film semiconductor structure is also described.
Findikoglu, Alp T. (Los Alamos, NM); Matias, Vladimir (Santa Fe, NM)
A New Earth-Abundant Semiconductor for Solar Energy Conversion
Presentation Title, G2, ZnSnN2: A New Earth-Abundant Semiconductor for Solar Energy Conversion. Author(s), Lise Lahourcade, Naomi C Coronel, Harry A�...
Semiconductor nanocrystals : synthesis, mechanisms of formation, and applications in biology
The primary focus of this thesis is the synthesis and applications of semiconductor nanocrystals, or quantum dots (QDs). Novel synthetic routes to ternary 1-III-VI QDs are presented, and we report the first highly luminescent ...
Allen, Peter M. (Peter Matthew)
AlGaN/GaN-based power semiconductor switches
AlGaN/GaN-based high-electron-mobility transistors (HEMTs) have great potential for their use as high efficiency and high speed power semiconductor switches, thanks to their high breakdown electric field, mobility and ...
Lu, Bin, Ph. D. Massachusetts Institute of Technology
Spin polarized transport effects in III-V semiconductor heterostructures
In the field of spintronics, GaMnAs, a ferromagnetic semiconductor, offers many advantages to study tunnel magnetotransport properties when used as an electrode. The complexity of the transport mechanisms associated with spin orbit coupled states make ...
J.-M. George
Printable semiconductor structures and related methods of making and assembling
The present invention provides a high yield pathway for the fabrication, transfer and assembly of high quality printable semiconductor elements having selected physical dimensions, shapes, compositions and spatial orientations. The compositions and methods of the present invention provide high precision registered transfer and integration of arrays of microsized and/or nanosized semiconductor structures onto substrates, including large area substrates and/or flexible substrates. In addition, the present invention provides methods of making printable semiconductor elements from low cost bulk materials, such as bulk silicon wafers, and smart-materials processing strategies that enable a versatile and commercially attractive printing-based fabrication platform for making a broad range of functional semiconductor devices.
Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Durham, NC); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Raleigh, NC); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)
Nuzzo, Ralph G. (Champaign, IL); Rogers, John A. (Champaign, IL); Menard, Etienne (Urbana, IL); Lee, Keon Jae (Tokyo, JP); Khang, Dahl-Young (Urbana, IL); Sun, Yugang (Westmont, IL); Meitl, Matthew (Champaign, IL); Zhu, Zhengtao (Rapid City, SD); Ko, Heung Cho (Urbana, IL); Mack, Shawn (Goleta, CA)
Nuzzo, Ralph G.; Rogers, John A.; Menard, Etienne; Lee, Keon Jae; Khang; , Dahl-Young; Sun, Yugang; Meitl, Matthew; Zhu, Zhengtao; Ko, Heung Cho; Mack, Shawn
Colloidal crystal formation in a semiconductor quantum plasma
The static shielding and the far-field dynamical oscillatory wake potentials in an ion-implanted piezoelectric semiconductor with colloid ions as test particles have been investigated in detail. The dielectric response function of the semiconductor is contributed by the quantum effect of electrons through the Bohm potential and lattice electron-phonon coupling effects. It is found that the quantum effect causes tighter binding of the electrons reducing the quantum Debye shielding length and the effective length of the wake potential to several angstroms. Hence, a quasiquantum lattice of colloid ions can be formed in the semiconductor in the quantum scales giving rise to drastic modifications of the ion-implanted semiconductor properties.
Zeba, I.; Uzma, Ch.; Jamil, M.; Salimullah, M. [Department of Physics, GC University, 54000 Lahore (Pakistan); Shukla, P. K. [Theoretische Physik IV, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)
Characterization of Novel Semiconductor Alloys for Band Gap Engineering
parameter for the lower-energy matrix like band. The fullthe optical matrix is constant with energy and given by: 2 menergy of the host semiconductor. Diagalization of the matrix
Broesler, Robert Joseph
A thermovoltaic semiconductor device including a plasma filter
A thermovoltaic energy conversion device and related method for converting thermal energy into an electrical potential are disclosed. An interference filter is provided on a semiconductor thermovoltaic cell to pre-filter black body radiation. The semiconductor thermovoltaic cell includes a P/N junction supported on a substrate which converts incident thermal energy below the semiconductor junction band gap into electrical potential. The semiconductor substrate is doped to provide a plasma filter which reflects back energy having a wavelength which is above the band gap and which is ineffectively filtered by the interference filter, through the P/N junction to the source of radiation thereby avoiding parasitic absorption of the unusable portion of the thermal radiation energy.
Baldasaro, Paul F.
Ultrafast nonlinear optical properties of passive and active semiconductor devices
Nonlinear optical properties and ultrafast carrier dynamics of slab-coupled optical waveguide amplifiers, silicon nanowaveguides, and III-V semiconductor saturable Bragg reflectors are studied. The limits imposed by two ...
Motamedi, Ali Reza
Varian Semiconductor Equipment Associates Inc VSEA | Open Energy
Varian Semiconductor Equipment Associates Inc VSEA Varian Semiconductor Equipment Associates Inc VSEA Jump to: navigation, search Name Varian Semiconductor Equipment Associates Inc (VSEA) Place Gloucester, Massachusetts Zip 1930 Sector Services Product Massachusetts-based, designs, manufactures, and services semiconductor processing equipment used in the fabrication of integrated circuits. Coordinates 37.413962°, -76.526305° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.413962,"lon":-76.526305,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Semiconductor nanocrystals covalently bound to solid inorganic surfaces using self-assembled monolayers
Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed. 10 figs.
Alivisatos, A.P.; Colvin, V.L.
Methods are described for attaching semiconductor nanocrystals to solid inorganic surfaces, using self-assembled bifunctional organic monolayers as bridge compounds. Two different techniques are presented. One relies on the formation of self-assembled monolayers on these surfaces. When exposed to solutions of nanocrystals, these bridge compounds bind the crystals and anchor them to the surface. The second technique attaches nanocrystals already coated with bridge compounds to the surfaces. Analyses indicate the presence of quantum confined clusters on the surfaces at the nanolayer level. These materials allow electron spectroscopies to be completed on condensed phase clusters, and represent a first step towards synthesis of an organized assembly of clusters. These new products are also disclosed.
Alivisatos, A. Paul (Berkeley, CA); Colvin, Vicki L. (Berkeley, CA)
Gas fixation solar cell using gas diffusion semiconductor electrode
A gas diffusion semiconductor electrode and solar cell and a process for gaseous fixation, such as nitrogen photoreduction, CO/sub 2/ photoreduction and fuel gas photo-oxidation are described. The gas diffusion photosensitive electrode has a central electrolyte porous matrix with an activated semiconductor material on one side adapted to be in contact with an electrolyte and a hydrophobic gas diffusion region on the opposite side adapted to be in contact with a supply of molecular gas.
Ang, P.G.; Sammells, A.F.
Thermally robust semiconductor optical amplifiers and laser diodes
A highly heat conductive layer is combined with or placed in the vicinity of the optical waveguide region of active semiconductor components. The thermally conductive layer enhances the conduction of heat away from the active region, which is where the heat is generated in active semiconductor components. This layer is placed so close to the optical region that it must also function as a waveguide and causes the active region to be nearly the same temperature as the ambient or heat sink. However, the semiconductor material itself should be as temperature insensitive as possible and therefore the invention combines a highly thermally conductive dielectric layer with improved semiconductor materials to achieve an overall package that offers improved thermal performance. The highly thermally conductive layer serves two basic functions. First, it provides a lower index material than the semiconductor device so that certain kinds of optical waveguides may be formed, e.g., a ridge waveguide. The second and most important function, as it relates to this invention, is that it provides a significantly higher thermal conductivity than the semiconductor material, which is the principal material in the fabrication of various optoelectronic devices.
Dijaili, Sol P. (Moraga, CA); Patterson, Frank G. (Danville, CA); Walker, Jeffrey D. (El Cerrito, CA); Deri, Robert J. (Pleasanton, CA); Petersen, Holly (Manteca, CA); Goward, William (Antioch, CA)
Nanoimprinted organic field-effect transistors: fabrication, transfer mechanism and solvent effects on device characteristics
The influence of solvent effects on the electrical characteristics of solution-processed organic field-effect transistors, with dihexylquaterthiophene (DH4T) as the active semiconductor material, has been investigated. A combination of nanoimprint and ... Keywords: nanoimprint lithography, organic field-effect transistors, short channel effects
A. P. Kam; J. Seekamp; V. Solovyev; C. Clavijo Cede�o; A. Goldschmidt; C. M. Sotomayor Torres
Electron transfer at sensitized semiconductor electrodes
Electron transfer from the excited state of sensitizing dyes to the conduction band of semiconductors has been studied through photoelectrochemical techniques. Two systems were analyzed in detail: rhodamine B on ZnO and rose bengal on TiO/sub 2/. Prior to electrochemical experimentation, the adsorption characteristics of these dyes were investigated using ZnO, ZnS, and TiO/sub 2/ single crystals as substrates. Absorbance measurements of the adsorbed dye were taken as a function of the solution concentration of the dye. Adsorption isotherms heats of adsorption were also established; they were similar to literature data reported for adsorption of these dyes on powdered substrates. Using the absorbance data, the quantum efficiency for photoinjection of electrons from rhodamine B into a ZnO electrode was determined to be 2.7 x 10/sup -2/. This value was independent of the dye surface concentration down to 50% coverage of the electrode. With the assumption that not all of the rhodamine B adsorbed on the electrode has the same rate of electron injection, a kinetic model for the time decay of the photocurrent was developed; data were analyzed according to this theory. A rate constant for photoreduction of the adsorbed dye was determined for the reducing agents. 86 references.
Spitler, M.T.
Enterprise-Wide Agreements | Department of Energy
Enterprise-Wide Enterprise-Wide Agreements Enterprise-Wide Agreements DOE's Office of the Chief Information Officer (OCIO) has designed the IT Acquisition: Enterprise-Wide Agreement (EWA) Program to develop and implement policies and procedures that support the identification, acquisition, oversight and compliance of enterprise licenses. EWAs are Department-wide acquisitions of widely used commercial software. The EWA Program has two core objectives to achieve the Program mission : Maximizing IT buying power and reducing total cost of ownership; Streamlining the IT total acquisition lifecycle. The EWA Program applies a centralized, cross-functional, strategic enterprise software solutions approach. The EWA Program leverages opportunities to create efficiencies and enhances the value of IT
Introducing transformational information technologies: the case of the world wide web technology
Transformational information technologies, by definition, transform organizations. Research on radical technological innovation and revolutionary change suggests a particular set of conditions and strategies for the successful introduction of transformational ... Keywords: diffusion of innovation, internet, organization design, technological innovation, transformational technology, world wide web
Sirkka L. Jarvenpaa; Blake Ives
Pulsed laser ablation of binary semiconductors: mechanisms of vaporisation and cluster formation
Formation of small clusters during pulsed ablation of two binary semiconductors, zinc oxide and indium phosphide, in vacuum by UV, visible, and IR laser radiation is comparatively studied. The irradiation conditions favourable for generation of neutral and charged Zn{sub n}O{sub m} and In{sub n}P{sub m} clusters of different stoichiometry in the ablation products are found. The size and composition of the clusters, their expansion dynamics and reactivity are analysed by time-of-flight mass spectrometry. A particular attention is paid to the mechanisms of ZnO and InP ablation as a function of laser fluence, with the use of different ablation models. It is established that ZnO evapourates congruently in a wide range of irradiation conditions, while InP ablation leads to enrichment of the target surface with indium. It is shown that this radically different character of semiconductor ablation determines the composition of the nanostructures formed: zinc oxide clusters are mainly stoichiometric, whereas In{sub n}P{sub m} particles are significantly enriched with indium. (photonics and nanotechnology)
Bulgakov, A V; Evtushenko, A B; Shukhov, Yu G [S S Kutateladze Institute of Thermophysics, Siberian Branch, Russian Academy of Sciences, Novosibirsk (Russian Federation); Ozerov, I; Marin, W [Universite de la Mediterranee, CINaM, UPR CNRS 3118, Marseille (France)
Impact of energy filtering and carrier localization on the thermoelectric properties of granular semiconductors
Energy filtering has been widely considered as a suitable tool to increase the thermoelectric performances of several classes of materials. In its essence, energy filtering provides a way to increase the Seebeck coefficient by introducing a strongly energy-dependent scattering mechanism. Under certain conditions, however, potential barriers may lead to carrier localization, that may also affect the thermoelectric properties of a material. A model is proposed, actually showing that randomly distributed potential barriers (as those found, e.g., in polycrystalline films) may lead to the simultaneous occurrence of energy filtering and carrier localization. Localization is shown to cause a decrease of the actual carrier density that, along with the quantum tunneling of carriers, may result in an unexpected increase of the power factor with the doping level. The model is corroborated toward experimental data gathered by several authors on degenerate polycrystalline silicon and lead telluride. - Graphical abstract: In heavily doped semiconductors potential barriers may lead to both carrier energy filtering and localization. This may lead to an enhancement of the thermoelectric properties of the material, resulting in an unexpected increase of the power factor with the doping level. Highlights: Black-Right-Pointing-Pointer Potential barriers are shown to lead to carrier localization in thermoelectric materials. Black-Right-Pointing-Pointer Evidence is put forward of the formation of a mobility edge. Black-Right-Pointing-Pointer Energy filtering and localization may explain the enhancement of power factor in degenerate semiconductors.
Narducci, Dario, E-mail: email@example.com [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy) [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Selezneva, Ekaterina [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy)] [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Cerofolini, Gianfranco [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy) [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Frabboni, Stefano; Ottaviani, Giampiero [Department of Physics, University of Modena and Reggio Emilia, via Campi 213, 41100 Modena (Italy)] [Department of Physics, University of Modena and Reggio Emilia, via Campi 213, 41100 Modena (Italy)
Organo luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes
A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) an affinity molecule linked to the semiconductor nanocrystal. The semiconductor nanocrystal is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Exposure of the semiconductor nanocrystal to excitation energy will excite the semiconductor nanocrystal causing the emission of electromagnetic radiation. Further described are processes for respectively: making the luminescent semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.
Weiss, Shimon (Pinole, CA); Bruchez, Jr., Marcel (Albany, CA); Alivisatos, Paul (Oakland, CA)
A regenerative frequency divider and multiplier having wide band input characteristics is presented. The circuit produces output oscillations having frequencies related by a fixed ratio to input oscillations over a wide band of frequencies. In accomplishing this end, the divider-multiplier includes a wide band input circuit coupled by mixer means to a wide band output circuit having a pass band related by a fixed ratio to that of the input circuit. A regenerative feedback circuit derives a fixed frequency ratio feedback signal from the output circuit and applies same to the mixer means in proper phase relation to sustain fixed frequency ratio oscillations in the output circuit.
Laine, E.F.
TRANSIMPEDAN E AMPLIFIER TE HNOLOGY SUMMARY Many applications require wide range detection, where detector current is converted to a voltage by a
Interconnection-Wide Transmission Planning Initiative: Topic...
State Agency Input Regarding Electric Resource and Transmission Planning in the Texas Interconnection Interconnection-Wide Transmission Planning Initiative: Topic B, State Agency...
Interconnection-Wide Transmission Planning Initiative: Topic B, State Agency Input Regarding Electric Resource and Transmission Planning in the Texas Interconnection...
Wide Electrochemical Window Solvents - Energy Innovation Portal
Biomass and Biofuels; ... This solvent has such a wide electrochemical window and such powerful solvating properties that it is an excellent target solvent ...
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Structure-fluctuation-induced abnormal thermoelectric properties in semiconductor copper selenide
Thermoelectric effects and related technologies have attracted a great interest due to the world-wide energy harvesting. Thermoelectricity has usually been considered in the context of stable material phases. Here we report that the fluctuation of structures during the second-order phase transition in Cu2Se semiconductor breaks the conventional trends of thermoelectric transports in normal phases, leading to a critically phase-transition-enhanced thermoelectric figure of merit zT above unity at 400K, a three times larger value than for the normal phases. Dynamic structural transformations introduce intensive fluctuations and extreme complexity, which enhance the carrier entropy and thus the thermopower, and strongly scatter carriers and phonons as well to make their transports behave critically.
Liu, Huili [Chinese Academy of Sciences; Shi, Xun [Chinese Academy of Sciences; Kirkham, Melanie J [ORNL; Wang, Hsin [ORNL; Li, Qiang [Brookhaven National Laboratory (BNL); Uher, Ctirad [University of Michigan; Zhang, Wenqing [Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS); Chen, Lidong [Chinese Academy of Sciences
Electrical Transport Through a Single Nanoscale SemiconductorBranch Point
Semiconductor tetrapods are three dimensional branched nanostructures, representing a new class of materials for electrical conduction. We employ the single electron transistor approach to investigate how charge carriers migrate through single nanoscale branch points of tetrapods. We find that carriers can delocalize across the branches or localize and hop between arms depending on their coupling strength. In addition, we demonstrate a new single-electron transistor operation scheme enabled by the multiple branched arms of a tetrapod: one arm can be used as a sensitive arm-gate to control the electrical transport through the whole system. Electrical transport through nanocrystals, molecules, nanowires and nanotubes display novel quantum phenomena. These can be studied using the single electron transistor approach to successively change the charge state by one, to reveal charging energies, electronic level spacings, and coupling between electronic, vibrational, and spin degrees of freedom. The advent of colloidal synthesis methods that produce branched nanostructures provides a new class of material which can act as conduits for electrical transport in hybrid organic-inorganic electrical devices such as light emitting diodes and solar cells. Already, the incorporation of branched nanostructures has yielded significant improvements in nanorod/polymer solar cells, where the specific pathways for charge migration can have a significant impact on device performance. Progress in this area requires an understanding of how electrons and holes migrate through individual branch points, for instance do charges delocalize across the branches or do they localize and hop between arms. Here we employ the single electron transistor approach to investigate the simplest three dimensional branched nanostructure, the semiconductor tetrapod, which consists of a pyramidal shaped zinc blende-structured ''core'' with four wurzite-structured arms projecting out at the tetrahedral angle. Monodisperse CdTe tetrapods with arms 8 nm in diameter and 150 nm in length were synthesized as previously reported. The tetrapods dispersed in toluene were deposited onto {approx}10 nm thick Si{sub 3}N{sub 4} dielectrics with alignment markers and a back gate (see Supporting Information). A tetrapod spontaneously orients with one arm pointing perpendicularly away from the substrate and three arms projecting down towards the surface. Individual 60 nm-thick Pd electrodes were placed by EBL onto each of the three arms downwards so that there are four terminals (three arms and a back gate) as shown schematically in Fig. 1 top inset. Figure 1 bottom inset shows a typical scanning electron micrograph (SEM) of the devices. The center brighter spot is due to the fourth arm pointing up away from the substrate although its controlled breaking is possible. The separation between the metal electrodes and the tetrapod branch point ranges from 30 to 80 nm in our devices. The devices were loaded into a He{sup 4}-flow cryostat for low-temperature ({approx}5K) electrical measurements.
Cui, Yi; Banin, Uri; Bjork, Mikael T.; Alivisatos, A. Paul
Efficient semiconductor light-emitting device and method
A semiconductor light-emitting device and method. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL).
Choquette, Kent D. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM); Schneider, Jr., Richard P. (Albuquerque, NM)
A semiconductor light-emitting device and method are disclosed. The semiconductor light-emitting device is provided with at least one control layer or control region which includes an annular oxidized portion thereof to channel an injection current into the active region, and to provide a lateral refractive index profile for index guiding the light generated within the device. A periodic composition grading of at least one of the mirror stacks in the device provides a reduced operating voltage of the device. The semiconductor light-emitting device has a high efficiency for light generation, and may be formed either as a resonant-cavity light-emitting diode (RCLED) or as a vertical-cavity surface-emitting laser (VCSEL). 12 figs.
Choquette, K.D.; Lear, K.L.; Schneider, R.P. Jr.
Optical Properties and Potential Applications of Doped Semiconductor Nanoparticles
Recent studies on the optical properties, in particular luminescence, of a variety of doped semiconductor nanoparticles are reviewed. The effects of quantum confinement, temperature, and pressure on luminescent properties are discussed. In addition, electroluminescence, cathodoluminescence, magnetoluminescence and related applications involving doped semiconductor nanoparticles are presented. A new phenomenon, upconversion luminescence of doped nanoparticles, is reviewed and its potential applications are discussed. While more research efforts are necessary in order to fully understand the fundamentals and explore the great technological potential behind doped nanoparticles, recent results already show that this is a new and exciting field with applications in many fields. In particular, the emerging field of ''spintronics'', where spin states are exploited in analogy to conventional electronic states, is discussed and the advantages of using doped semiconductor nanoparticles are elucidated.
Chen, Wei; Zhang, Jin Z.; Joly, Alan G.
Wavelength-resonant surface-emitting semiconductor laser
A wavelength resonant semiconductor gain medium is disclosed. The essential feature of this medium is a multiplicity of quantum-well gain regions separated by semiconductor spacer regions of higher bandgap. Each period of this medium consisting of one quantum-well region and the adjacent spacer region is chosen such that the total width is equal to an integral multiple of 1/2 the wavelength in the medium of the radiation with which the medium is interacting. Optical, electron-beam and electrical injection pumping of the medium is disclosed. This medium may be used as a laser medium for single devices or arrays either with or without reflectors, which may be either semiconductor or external.
Brueck, Steven R. J. (Albuquerque, NM); Schaus, Christian F. (Albuquerque, NM); Osinski, Marek A. (Albuquerque, NM); McInerney, John G. (Cedar Crest, NM); Raja, M. Yasin A. (Albuquerque, NM); Brennan, Thomas M. (Albuquerque, NM); Hammons, Burrell E. (Tijeras, NM)
This chapter provides an overview of some recent research activities on the study of optical and dynamic properties of semiconductor nanomaterials. The emphasis is on unique aspects of these properties in nanostructures as compared to bulk materials. Linear, including absorption and luminescence, and nonlinear optical as well as dynamic properties of semiconductor nanoparticles are discussed with focus on their dependence on particle size, shape, and surface characteristics. Both doped and undoped semiconductor nanomaterials are highlighted and contrasted to illustrate the use of doping to effectively alter and probe nanomaterial properties. Some emerging applications of optical nanomaterials are discussed towards the end of the chapter, including solar energy conversion, optical sensing of chemicals and biochemicals, solid state lighting, photocatalysis, and photoelectrochemistry.
Grant, C D; Zhang, J Z
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Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach
Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach Jump to: navigation, search Tool Summary Name: Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach Agency/Company /Organization: National Renewable Energy Laboratory, United States Department of Energy Sector: Energy Focus Area: Renewable Energy Topics: Implementation, Policies/deployment programs Resource Type: Publications, Guide/manual, Lessons learned/best practices Website: www.nrel.gov/applying_technologies/state_local_activities/pdfs/48689.p Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach Screenshot References: Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach[1] Logo: Effective Community-Wide Policy Technical Assistance: The NREL/DOE Approach
Ultra-wide bandwidth piezoelectric energy harvesting
Here, we present an ultra wide-bandwidth energy harvester by exploiting the nonlinear stiffness of a doubly clamped microelectromechanical systems (MEMSs) resonator. The stretching strain in a doubly clamped beam shows a ...
China Joins WorldWideScience Alliance
the addition of more Chinese sources to WorldWideScience.org after a successful test period. DOE's Office of Science, through (OSTI), serves as the Operating Agent for...
WorldWideScience.org Goes Multilingual
FOR IMMEDIATE RELEASE Friday, June 11, 2010 WorldWideScience.org Goes Multilingual OAK RIDGE, TN - Now you can find non-English scientific literature from databases in...
Agency-Wide Screening | Department of Energy
Agency-Wide Screening Agency-Wide Screening Agency-Wide Screening October 16, 2013 - 4:36pm Addthis Federal agencies face energy-related requirements on new construction projects and major renovations. These Federal requirements range from reductions in fossil-fuel use to specifying the use of certain renewable energy technologies. As some agencies have already found out, not all sites or construction projects are created equal. Because many of the requirements are agency-wide, an effective and efficient way to meet these requirements is to consider and identify appropriate locations for these technologies across all agency land and building assets. FEMP can help Federal agencies conduct a renewable energy screening at all of its sites, or just at all of its upcoming construction project
Organic-vapor-liquid-solid deposition with an impinging gas jet Daniel W. Shaw, Kevin Bufkin, Alexandr A. Baronov, Brad L. Johnson, and David L. Patrick
Organic-vapor-liquid-solid deposition with an impinging gas jet Daniel W. Shaw, Kevin Bufkin gas jet to a substrate coated by a thin liquid solvent layer. Films of the organic semiconductor, and the results compared to experiment. The combination of gas jet delivery with an organic-vapor-liquid
Patrick, David L.
Below-bandgap excitation of bulk semiconductors by twisted light
I theoretically investigate the response of bulk semiconductors to excitation by twisted light below the energy bandgap. To this end, I modify a well-known model of light-semiconductor interaction to account for the conservation of the light's momentum. I show that the excited states can be thought of as a superposition of slightly perturbed exciton states undergoing a complex center-of-mass motion. In addition, the absorption would occur at a slightly shifted energy (compared to plane waves) and would exhibit complex spatial patterns in the polarization and current.
Quinteiro, G F
Low temperature production of large-grain polycrystalline semiconductors
An oxide or nitride layer is provided on an amorphous semiconductor layer prior to performing metal-induced crystallization of the semiconductor layer. The oxide or nitride layer facilitates conversion of the amorphous material into large grain polycrystalline material. Hence, a native silicon dioxide layer provided on hydrogenated amorphous silicon (a-Si:H), followed by deposited Al permits induced crystallization at temperatures far below the solid phase crystallization temperature of a-Si. Solar cells and thin film transistors can be prepared using this method.
Naseem, Hameed A. (Fayetteville, AR); Albarghouti, Marwan (Loudonville, NY)
Low Power, Red, Green and Blue Carbon Nanotube Enabled Vertical Organic Light Emitting Transistors for Active Matrix OLED Displays
Organic semiconductors are potential alternatives to polycrystalline silicon as the semiconductor used in the backplane of active matrix organic light emitting diode displays. Demonstrated here is a light-emitting transistor with an organic channel, operating with low power dissipation at low voltage, and high aperture ratio, in three colors: red, green and blue. The single-wall carbon nanotube network source electrode is responsible for the high level of performance demonstrated. A major benefit enabled by this architecture is the integration of the drive transistor, storage capacitor and light emitter into a single device. Performance comparable to commercialized polycrystalline-silicon TFT driven OLEDs is demonstrated.
McCarthy, M. A. [University of Florida, Gainesville; Liu, B. [University of Florida, Gainesville; Donoghue, E. P. [University of Florida, Gainesville; Kravchenko, Ivan I [ORNL; Kim, D. Y. [University of Florida, Gainesville; So, Franky [University of Florida, Gainesville; Rinzler, A. G. [University of Florida, Gainesville
Building Structural Complexity in Semiconductor Nanocrystals through Chemical Transformations
Methods are presented for synthesizing nanocrystal heterostructures comprised of two semiconductor materials epitaxially attached within individual nanostructures. The chemical transformation of cation exchange, where the cations within the lattice of an ionic nanocrystal are replaced with a different metal ion species, is used to alter the chemical composition at specific regions ofa nanocrystal. Partial cation exchange was performed in cadmium sulfide (CdS) nanorods of well-defined size and shape to examine the spatial organization of materials within the resulting nanocrystal heterostructures. The selectivity for cation exchange to take place at different facets of the nanocrystal plays an important role in determining the resulting morphology of the binary heterostructure. The exchange of copper (I) (Cu+) cations in CdS nanorods occurs preferentially at the ends of the nanorods. Theoretical modeling of epitaxial attachments between different facets of CdS and Cu2S indicate that the selectivity for cation exchange at the ends of the nanorods is a result of the low formation energy of the interfaces produced. During silver (I) (Ag+) cation exchange in CdS nanorods, non-selective nucleation of silver sulfide (Ag2S), followed by partial phase segregation leads to significant changes in the spatial arrangement of CdS and Ag2S regions at the exchange reaction proceeds through the nanocrystal. A well-ordered striped pattern of alternating CdS and Ag2S segments is found at intermediate fractions of exchange. The forces mediating this spontaneous process are a combination of Ostwald ripening to reduce the interfacial area along with a strain-induced repulsive interaction between Ag2S segments. To elucidate why Cu+ and Ag+ cation exchange with CdS nanorods produce different morphologies, models for epitaxial attachments between various facets of CdS with Cu2S or Ag2S lattices were used to calculate interface formation energies. The formation energies indicate the favorability for interface nucleation at different facets of the nanorod and the stability of the interfaces during growth of the secondary material (Cu2S or Ag2S) within the CdS nanocrystal. The physical properties of the CdS-Ag2S and CdS-Cu2S binary nanorods are discussed in terms of the electronic structure of their components and the heterostructure morphology.
Sadtler, Bryce F
Optically Detected Magnetic Resonance Studies on ?-conjugated semiconductor systems
Optically Detected Magnetic Resonance (ODMR) techniques were used to investigate the dynamics of excitons and charge carriers in ?-conjugated organic semiconductors. Degradation behavior of the negative spin-1/2 electroluminescence-detected magnetic resonance (ELDMR) was observed in Alq3 devices. The increase in the resonance amplitude implies an increasing bipolaron formation during degradation, which might be the result of growth of charge traps in the device. The same behavior of the negative spin-1/2 ELDMR was observed in 2wt% Rubrene doped Tris(8-hydroxyquinolinato)aluminium (Alq3) devices. However, with increasing injection current, a positive spin-1/2 ELDMR, together with positive spin 1 triplet powder patterns at {delta}m{sub S}={+-}1 and {delta}m{sub S}={+-}2, emerges. Due to the similarities in the frequency dependences of single and double modulated ELDMR and the photoluminescence-detected magnetic resonance (PLDMR) results in poly[2-methoxy-5-(2 -ethyl-hexyloxy)-1,4-phenyl ene vinylene] (MEH-PPV) films, the mechanism for this positive spin-1/2 ELDMR was assigned to enhanced triplet-polaron quenching under resonance conditions. The ELDMR in rubrene doped Alq3 devices provides a path to investigate charge distribution in the device under operational conditions. Combining the results of several devices with different carrier blocking properties and the results from transient EL, it was concluded trions not only exist near buffer layer but also exist in the electron transport layer. This TPQ model can also be used to explain the positive spin-1/2 PLDMR in poly(3-hexylthiophene) (P3HT) films at low temperature and in MEH-PPV films at various temperatures up to room temperature. Through quantitative analysis, TE-polaron quenching (TPQ) model is shown having the ability to explain most behaviors of the positive spin-1/2 resonance. Photocurrent detected magnetic resonance (PCDMR) studies on MEH-PPV devices revealed a novel transient resonance signal. The signal may originate from the higher concentration of deep traps near cathode. A quantitative analysis based on this assumption was carried out and found to be consistent with the experimental results.
Chen, Ying
System design and simulation of constant temperature box using semiconductor refrigeration device
This paper presents the variation law of temperature in three-dimensional space, which is cooled by the refrigeration provided by the cold side of a semiconductor. The mathematical model of the temperature field of the semiconductor refrigeration ... Keywords: constant temperature box, forced convection, mathematical modelling, numerical simulation, semiconductor refrigeration, system design
Hui Zhang; Kuang-Chao Fan; Jun Wang
High-density organic light emitting diodes by nanoimprint technology Krutarth Trivedi, Caleb Nelson, Li Tao, Mathew Goeckner, Walter Hua)
High-density organic light emitting diodes by nanoimprint technology Krutarth Trivedi, Caleb Nelson sources. Despite the considerable development of inorganic semiconductor based light emitting diodes of miniaturization to nanoscale. Organic light emitting diode (OLED) technology is immune to quantum confinement
Hu, Wenchuang "Walter"
Integration of organic insulator and self-assembled gold nanoparticles on Si MOSFET for novel non-volatile memory cells
We have fabricated a hybrid non-volatile gold nanoparticle floating-gate memory metal insulator semiconductor field effect transistor (MISFET) device combining silicon technology and organic thin film deposition. The nanoparticles are deposited by chemical ... Keywords: hybrid Silicon-organic memory, nanocrystal memory, nanoparticles, non-volatile memory
S. Kolliopoulou; P. Dimitrakis; P. Normand; H.-L. Zhang; N. Cant; S. D. Evans; S. Paul; C. Pearson; A. Molloy; M. C. Petty; D. Tsoukalas
Generator of pumping pulses for powerful semiconductor lasers
The generator of electric and optic pulses are built using powerful MOS transistors and an ILPI-103 semiconductor laser generates pumping pulses with an amplitude of 15 A and optic pulses with a duration of 9 to 30 nsec at a repetition rate of up to 90 kHz. The output signal is TTL. The device is designed for open optic communication lines.
An, V.I.; Kolesnikov, Yu.Yu. [Voronezh Scientific Research Institute of Communications, Voronezh (Russian Federation)
Quantum Optics: Colloidal Fluorescent Semiconductor Nanocrystals (Quantum Dots)
U ncorrected Proof Chapter 3 Quantum Optics: Colloidal Fluorescent Semiconductor Nanocrystals (Quantum Dots) in Single-Molecule Detection and Imaging Laurent A. Bentolila, Xavier Michalet, and Shimon quantum dots (QDs), have emerged as new powerful fluorescent probes for in vitro and in vivo biological
Michalet, Xavier
User experience research in the semiconductor factory: a contradiction?
No doubt, user experience (UX) has become of high relevance within the HCI community. Within this paper, we present initial results from a qualitative study on UX in the factory context, more precisely in a semiconductor factory. We highlight the challenges ... Keywords: factory context, probing, user experience, user study
Marianna Obrist; Wolfgang Reitberger; Daniela Wurhofer; Florian F�rster; Manfred Tscheligi
The new -NMR facility at TRIUMF and applications in semiconductors
The new -NMR facility at TRIUMF and applications in semiconductors K.H. Chow a, Z. Salman b R facililty for conducting beta-detected nuclear magnetic resonance (-NMR) investigations of condensed matter facility are described, and some preliminary results on 8Li+ in GaAs are presented. Key words: -NMR
Baartman, Richard Abram
[Electron transfer rates at semiconductor/liquid interfaces]. Progress report
Work has focused on several aspects of the fundamental chemistry and physics semiconductor/liquid junction behavior. These projects have been directed primarily towards GaAs/liquid contacts, because GaAs/liquid systems provide high energy conversion efficiencies and offer an opportunity to gain mechanistic understanding of the factors that are important to control in an efficient photoelectrochemical energy conversion system.
Lewis, N.S.
(Electron transfer rates at semiconductor/liquid interfaces)
Chemosensors, biosensors, and microsystems based on standard semiconductor technology (CMOS)
Microfabrication techniques and, in particular, complementary metal oxide semiconductor (CMOS) technology have been used to devise chemosensors, biosensors, and microsystems in a generic approach. Examples of micromachined bio/chemosensors, such as cantilevers ... Keywords: CMOS, bioelectronics, biomicrosystem, biosensor, cells, chemical sensor, microelectronics
Andreas Hierlemann
Electronic displays using optically pumped luminescent semiconductor nanocrystals
A multicolor electronic display is based on an array of luminescent semiconductor nanocrystals. Nanocrystals which emit light of different colors are grouped into pixels. The nanocrystals are optically pumped to produce a multicolor display. Different sized nanocrystals are used to produce the different colors. A variety of pixel addressing systems can be used.
Weiss, Shimon (Pinole, CA); Schlamp, Michael C. (Plainsboro, NJ); Alivisatos, A. Paul (Oakland, CA)
Ados Co Ltd Dong Yang Semiconductor | Open Energy Information
Ados Co Ltd Dong Yang Semiconductor Ados Co Ltd Dong Yang Semiconductor Jump to: navigation, search Name Ados Co Ltd (Dong Yang Semiconductor) Place Seoul, Seoul, Korea (Republic) Product Korean manufacturer of semiconductors; through Ersol's technology, will develop PV plants and begin to roll out crystalline silicon wafers and cells by H2 2007. Coordinates 37.557121°, 126.977379° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":37.557121,"lon":126.977379,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}
Draft Site-Wide Environmental Impact Statement
Site-Wide Environmental Impact Statement Site-Wide Environmental Impact Statement for the Y-12 National Security Complex October 2009 U.S. Department of Energy National Nuclear Security Administration Y-12 Site Office DOE/EIS-0387 COVER SHEET RESPONSIBLE AGENCY: United States (U.S.) Department of Energy (DOE), National Nuclear Security Administration (NNSA) TITLE: Draft Site-wide Environmental Impact Statement for the Y-12 National Security Complex (DOE/EIS-0387) (Draft Y-12 SWEIS) CONTACT: For further information on this SWEIS, For general information on the DOE contact: National Environmental Policy Act (NEPA) process, contact: Pam Gorman Carol Borgstrom, Director Y-12 SWEIS Document Manager Office of NEPA Policy and Compliance, GC-20 Y-12 Site Office U.S. Department of Energy
The Los Alamos National Laboratory, on behalf of the Hewlett-Packard Company, is conducting tests of a closed-loop CO{sub 2}-based supercritical fluid process, known as Supercritical CO{sub 2} Resist Remover (SCORR). We have shown that this treatment process is effective in removing hard-baked, ion-implanted photoresists, and appears to be fully compatible with metallization systems. We are now performing experiments on production wafers to assess not only photoresist removal, but also residual surface contamination due to particulate and trace metals. Dense-phase (liquid or supercritical) CO{sub 2}, since it is non-polar, acts like an organic solvent and therefore has an inherently high volubility for organic compounds such as oils and greases. Also, dense CO{sub 2} has a low-viscosity and a low dielectric constant. Finally, CO{sub 2} in the liquid and supercritical fluid states can solubilize metal completing agents and surfactants. This combination of properties has interesting implications for the removal not only of organic films, but also trace metals and inorganic particulate. In this paper we discuss the possibility of using CO{sub 2} as a precision-cleaning solvent, with particular emphasis on semiconductor surfaces.
Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction
A more recent product is now available that contains this report, along with additional presentation materials to facilitate its use. See Product 1018109. This report provides guidance arising from the EPRI initiative on IC Strategies for Plant-Wide and Fleet-Wide Cost Reduction. The document describes a wide range of options while emphasizing integrated modernization across the plant or fleet. Coordinated improvements to shared communications and computing infrastructure, plant processes, and organizat...
A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in the probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.
Semiconductor nanocrystal probes for biological applications and process for making and using such probes
A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to the one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.
Weiss, Shimon (Pinole, CA); Bruchez, Marcel (Newark, CA); Alivisatos, Paul (Oakland, CA)
A semiconductor nanocrystal compound is described capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affity molecule. The compound is linked to an affinity molecule to form a semiconductor nanocrystal probe capable of bonding with a detectable substance. Subsequent exposure to excitation energy will excite the semiconductor nanocrystal in he probe, causing the emission of electromagnetic radiation. Further described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and using the probe to determine the presence of a detectable substance in a material.
Weiss, Shimon; Bruchez, Marcel; Alivisatos, Paul
Methods of use of semiconductor nanocrystal probes for treating a material
A semiconductor nanocrystal compound and probe are described. The compound is capable of linking to one or more affinity molecules. The compound comprises (1) one or more semiconductor nanocrystals capable of, in response to exposure to a first energy, providing a second energy, and (2) one or more linking agents, having a first portion linked to one or more semiconductor nanocrystals and a second portion capable of linking to one or more affinity molecules. One or more semiconductor nanocrystal compounds are linked to one or more affinity molecules to form a semiconductor nanocrystal probe capable of bonding with one or more detectable substances in a material being analyzed, and capable of, in response to exposure to a first energy, providing a second energy. Also described are processes for respectively: making the semiconductor nanocrystal compound; making the semiconductor nanocrystal probe; and treating materials with the probe.
Weiss, Shimon (Los Angeles, CA); Bruchez, Marcel (Belmont, CA); Alivisatos, Paul (Oakland, CA)
Recent advances in solid-state organic lasers
Organic solid-state lasers are reviewed, with a special emphasis on works published during the last decade. Referring originally to dyes in solid-state polymeric matrices, organic lasers also include the rich family of organic semiconductors, paced by the rapid development of organic light emitting diodes. Organic lasers are broadly tunable coherent sources are potentially compact, convenient and manufactured at low-costs. In this review, we describe the basic photophysics of the materials used as gain media in organic lasers with a specific look at the distinctive feature of dyes and semiconductors. We also outline the laser architectures used in state-of-the-art organic lasers and the performances of these devices with regard to output power, lifetime, and beam quality. A survey of the recent trends in the field is given, highlighting the latest developments in terms of wavelength coverage, wavelength agility, efficiency and compactness, or towards integrated low-cost sources, with a special focus on the gr...
Chenais, S�bastien; 10.1002/pi.3173
Traffic data repository at the WIDE project
It becomes increasingly important for both network researchers and operators to know the trend of network traffic and to find anomaly in their network traffic. This paper describes an on-going effort within the WIDE project to collect a set of free tools ...
Kenjiro Cho; Koushirou Mitsuya; Akira Kato
EIS-0387: DOE Notice of Availability of the Draft Site-Wide Environmental
DOE Notice of Availability of the Draft Site-Wide DOE Notice of Availability of the Draft Site-Wide Environmental Impact Statement EIS-0387: DOE Notice of Availability of the Draft Site-Wide Environmental Impact Statement Y-12 National Security Complex, Oak Ridge, TN The National Nuclear Security Administration (NNSA), a separately-organized agency within the Department of Energy (DOE), announces the availability of the Draft Site-Wide Environmental Impact Statement for the Y-12 National Security Complex (Draft Y-12 SWEIS, DOE/EIS-0387) (74 FR 56189) (October 2009) National Nuclear Security Administration Notice of Availability of the Draft Site-Wide Environmental Impact Statement for the Y-12 National Security Complex, EIS-0387(October 2009) More Documents & Publications EIS-0387: Record of Decision
DFAS Wide-Area Workflow Issues
DFAS Wide-Area Workflow DFAS Wide-Area Workflow Issues Mark Shvartzman Sr. Project Manager, CEM, CEA Southern California Edison Presented at the Spring FUPWG Meeting April 20, 2011 What We Are Going to Discuss * Review Delivery Order or Task Order for accounting lines information. * Contact Contracting Officer or Contracting specialist and request Pay DoDAAC and Ext. information * Create Payment Log by ACRN * Start creating Invoice How the WAWF works and how to navigate through: 2 CONTRACT N68711-03-G-4019 DO#0028 Pay Records Bill by CLIN Award $ by CLIN Billed To Date Invoice number Pay Total Balance by CLIN 7500009733 $330,899.11 CLIN 0001AA 674,220.00 674,220.00 7500009733 7500012596 674,220.00 0.00 7500012596 $641,344.69 CLIN 0001AB 325,780.00 298023.8 27,756.20 7500012596 7500015079 325,780.00
Ultrafast dynamics of excitons and charges in organic materials and semiconductor nanocrystals
and electronic properties that are of interest for applications in e.g. solar cells, photodiodes, light- emitting diodes, field-effect transistors and nanoscale molecular electronics. We studied the mechanism of charge
Schuster, Assaf
fabrication, patterned indium-tin oxide (ITO) coated glassis usually transparent indium tin oxide (ITO), poly(3,4-
Fluid characterisation and drop impact in inkjet printing for organic semiconductor devices
elements provides a typical example. A hole-injection layer and a luminescent layer are formed between a cathode and a transparent indium tin oxide (ITO) anode coated on to a glass substrate. The two layers are deposited by regions of less wettable... -suited for integration with metal oxide dielectric layers, which could enable improved optical and electrical performance. Figure 2-12. Photograph of a 10,000 cd m-2 OLED printed using Ir-based polyhedral oligomeric silsesquioxane (POSS) macromolecules emitting at a...
Jung, Sungjune
H4, Advanced X-Ray Peak Shape Analysis of Organic Semiconductors
L6, PECVD-SiN, Si or Si/Al2O3-Capped ED-Mode AlN/GaN Inverters � Hide details for [
Industry-Wide Database: Circuit Breakers
Best practice maintenance and asset management decisions are based on risks associated with actual equipment condition and performance. However, little effort has been made to systematically collect and analyze such industry information for high-voltage circuit breakers. This document presents the results of the initial effort of the Electric Power Research Institute (EPRI) to explore the development of an industry-wide database (IDB) for high-voltage circuit breakers (HVCBs). The project identified ...
TCP performance analysis for wide area networks
Even though networks have been getting faster, perceived throughput at the application level has not increased accordingly. In an attempt to identify many of the performance bottlenecks, we collected and analyzed data over a wide area network (WAN) at T3 (45 Mbps) bandwidth. The information gained will assist in designing new protocols and/or algorithms that are consistent with future high- speed requirements.
Chen, H.Y.; Hutchins, J.A. [Sandia National Labs., Livermore, CA (United States); Testi, N. [Sandia National Labs., Albuquerque, NM (United States)
Method of plasma etching GA-based compound semiconductors
A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent thereto. The chamber contains a Ga-based compound semiconductor sample in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. SiCl.sub.4 and Ar gases are flowed into the chamber. RF power is supplied to the platen at a first power level, and RF power is supplied to the source electrode. A plasma is generated. Then, RF power is supplied to the platen at a second power level lower than the first power level and no greater than about 30 W. Regions of a surface of the sample adjacent to one or more masked portions of the surface are etched at a rate of no more than about 25 nm/min to create a substantially smooth etched surface.
Qiu, Weibin; Goddard, Lynford L.
Semiconductor laser devices having lateral refractive index tailoring
A broad-area semiconductor laser diode includes an active lasing region interposed between an upper and a lower cladding layer, the laser diode further comprising structure for controllably varying a lateral refractive index profile of the diode to substantially compensate for an effect of junction heating during operation. In embodiments disclosed the controlling structure comprises resistive heating strips or non-radiative linear junctions disposed parallel to the active region. Another embodiment discloses a multi-layered upper cladding region selectively disordered by implanted or diffused dopant impurities. Still another embodiment discloses an upper cladding layer of variable thickness that is convex in shape and symmetrically disposed about a central axis of the active region. The teaching of the invention is also shown to be applicable to arrays of semiconductor laser diodes.
Ashby, C.I.H.; Hadley, G.R.; Hohimer, J.P.; Owyoung, A.
Semiconductor Nanocrystals-Based White Light Emitting Diodes
In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid state lighting, such as white light emitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement could cut the ever-increasing energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, we highlight the recent progress in semiconductor nanocrystals-based WLEDs, compare different approaches for generating white light, and discuss the benefits and challenges of the solid state lighting technology.
Dai, Quanqin [ORNL; Hu, Michael Z. [ORNL; Duty, Chad E [ORNL
Semiconductor-Nanocrystals-Based White Light-Emitting Diodes
In response to the demands for energy and the concerns of global warming and climate change, energy efficient and environmentally friendly solid-state lighting, such as white lightemitting diodes (WLEDs), is considered to be the most promising and suitable light source. Because of their small size, high efficiency, and long lifetime, WLEDs based on colloidal semiconductor nanocrystals (or quantum dots) are emerging as a completely new technology platform for the development of flat-panel displays and solid-state lighting, exhibiting the potential to replace the conventionally used incandescent and fluorescent lamps. This replacement can cut the ever-increasing level of energy consumption, solve the problem of rapidly depleting fossil fuel reserves, and improve the quality of the global environment. In this review, the recent progress in semiconductor-nanocrystals-based WLEDs is highlighted, the different approaches for generating white light are compared, and the benefits and challenges of the solid-state lighting technology are discussed.
Dai, Quanqin [ORNL; Duty, Chad E [ORNL; Hu, Michael Z. [ORNL
Method for mapping charge pulses in semiconductor radiation detectors
An efficient method for determining the distribution of charge pulses produced by semiconductor detectors is presented. The method is based on a quasi-steady-state model for semiconductor detector operation. A complete description of the model and underlying assumptions is given. Mapping of charge pulses is accomplished by solving an adjoint carrier continuity equation. The solution of the adjoint equation yields Green`s function, a time- and position-dependent map that contains all possible charge pulses that can be produced by the detector for charge generated at discrete locations (e.g., by gamma-ray interactions). Because the map is generated by solving a single, time-dependent problem, the potential for reduction in computational effort over direct mapping methods is significant, particularly for detectors with complex electrode structures. In this paper, the adjoint equation is derived and the mapping method is illustrated for a simple case.
Prettyman, T.H.
Hybrid high-temperature superconductor-semiconductor tunnel diode
We report the demonstration of hybrid high-Tc-superconductor-semiconductor tunnel junctions, enabling new interdisciplinary directions in condensed matter research. The devices were fabricated by our newly-developed mechanical bonding technique, resulting in high-Tc-semiconductor planar junctions acting as superconducting tunnel diodes. Tunneling-spectra characterization of the hybrid junctions of Bi2Sr2CaCu2O8+{\\delta} combined with bulk GaAs, or a GaAs/AlGaAs quantum well, exhibits excess voltage and nonlinearity - in good agreement with theoretical predictions for a d-wave superconductor-normal material junction, and similar to spectra obtained in scanning tunneling microscopy. Additional junctions are demonstrated using Bi2Sr2CaCu2O8+{\\delta} combined with graphite or Bi2Te3. Our results pave the way for new methods in unconventional superconductivity studies, novel materials and quantum technology applications.
Alex Hayat; Parisa Zareapour; Shu Yang F. Zhao; Achint Jain; Igor G. Savelyev; Marina Blumin; Zhijun Xu; Alina Yang; G. D. Gu; Harry E. Ruda; Shuang Jia; R. J. Cava; Aephraim M. Steinberg; Kenneth S. Burch
Semiconductor light source with electrically tunable emission wavelength
A semiconductor light source comprises a substrate, lower and upper claddings, a waveguide region with imbedded active area, and electrical contacts to provide voltage necessary for the wavelength tuning. The active region includes single or several heterojunction periods sandwiched between charge accumulation layers. Each of the active region periods comprises higher and lower affinity semiconductor layers with type-II band alignment. The charge carrier accumulation in the charge accumulation layers results in electric field build-up and leads to the formation of generally triangular electron and hole potential wells in the higher and lower affinity layers. Nonequillibrium carriers can be created in the active region by means of electrical injection or optical pumping. The ground state energy in the triangular wells and the radiation wavelength can be tuned by changing the voltage drop across the active region.
Belenky, Gregory (Port Jefferson, NY); Bruno, John D. (Bowie, MD); Kisin, Mikhail V. (Centereach, NY); Luryi, Serge (Setauket, NY); Shterengas, Leon (Centereach, NY); Suchalkin, Sergey (Centereach, NY); Tober, Richard L. (Elkridge, MD)
Method of plasma etching Ga-based compound semiconductors
A method of plasma etching Ga-based compound semiconductors includes providing a process chamber and a source electrode adjacent to the process chamber. The process chamber contains a sample comprising a Ga-based compound semiconductor. The sample is in contact with a platen which is electrically connected to a first power supply, and the source electrode is electrically connected to a second power supply. The method includes flowing SiCl.sub.4 gas into the chamber, flowing Ar gas into the chamber, and flowing H.sub.2 gas into the chamber. RF power is supplied independently to the source electrode and the platen. A plasma is generated based on the gases in the process chamber, and regions of a surface of the sample adjacent to one or more masked portions of the surface are etched to create a substantially smooth etched surface including features having substantially vertical walls beneath the masked portions.
Semiconductor-based, large-area, flexible, electronic devices
Novel articles and methods to fabricate the same resulting in flexible, large-area, triaxially textured, single-crystal or single-crystal-like, semiconductor-based, electronic devices are disclosed. Potential applications of resulting articles are in areas of photovoltaic devices, flat-panel displays, thermophotovoltaic devices, ferroelectric devices, light emitting diode devices, computer hard disc drive devices, magnetoresistance based devices, photoluminescence based devices, non-volatile memory devices, dielectric devices, thermoelectric devices and quantum dot laser devices.
Goyal, Amit (Knoxville, TN)
Method for measuring the drift mobility in doped semiconductors
A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorous. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells.
Crandall, Richard S. (Princeton, NJ)
A method for measuring the drift mobility of majority carriers in semiconductors consists of measuring the current transient in a Schottky-barrier device following the termination of a forward bias pulse. An example is given using an amorphous silicon hydrogenated material doped with 0.2% phosphorus. The method is particularly useful with material in which the dielectric relaxation time is shorter than the carrier transit time. It is particularly useful in material useful in solar cells. 10 figs.
Crandall, R.S.
Energy Conservation Through Water Usage Reduction in the Semiconductor Industry
The semiconductor industry uses large amounts of Ultrapure Water (UPW) in the wafer fabrication process. Producing UPW involves energy-intensive operations, such as membrane separations, ultraviolet lamps, and continuous pumping and recirculation systems. Indirect energy costs can also be allocated to steps in the UPW process. Motorola recognizes that by reducing UPW consumption, energy savings will result. Energy conservation can also be achieved by improving the UPW generation process itself and by recycling or reclaiming UPW and other water streams.
Mendicino, L.; McCormack, K.; Gibson, S.; Patton, B.; Lyon, D.; Covington, J.
Proceedings of the 13th international World Wide Web conference on Alternate track papers & posters
We welcome you to New York and WWW2004, the thirteenth conference in the series organized by the International World Wide Web Conference Committee. This should be both an exciting conference and a very enjoyable experience. New York is a center of communications, ...
Stuart Feldman; Mike Uretsky; Marc Najork; Craig Wills
Electronic Structure and Magnetism in Diluted Magnetic Semiconductors
Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.
Nonlinear fibre-optic devices pumped by semiconductor disk lasers
Semiconductor disk lasers offer a unique combination of characteristics that are particularly attractive for pumping Raman lasers and amplifiers. The advantages of disk lasers include a low relative noise intensity (-150 dB Hz{sup -1}), scalable (on the order of several watts) output power, and nearly diffraction-limited beam quality resulting in a high ({approx}70 % - 90 %) coupling efficiency into a single-mode fibre. Using this technology, low-noise fibre Raman amplifiers operating at 1.3 {mu}m in co-propagation configuration are developed. A hybrid Raman-bismuth doped fibre amplifier is proposed to further increase the pump conversion efficiency. The possibility of fabricating mode-locked picosecond fibre lasers operating under both normal and anomalous dispersion is shown experimentally. We demonstrate the operation of 1.38-{mu}m and 1.6-{mu}m passively mode-locked Raman fibre lasers pumped by 1.29-{mu}m and 1.48-{mu}m semiconductor disk lasers and producing 1.97- and 2.7-ps pulses, respectively. Using a picosecond semiconductor disk laser amplified with an ytterbium-erbium fibre amplifier, the supercontinuum generation spanning from 1.35 {mu}m to 2 {mu}m is achieved with an average power of 3.5 W. (invited paper)
Chamorovskiy, A Yu; Okhotnikov, Oleg G [Optoelectronics Research Center, Tampere University of Technology, Tampere (Finland)
Electronic Structure and Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Electronic Structure and Magnetism in Diluted Magnetic Semiconductors Print Wednesday, 29 November 2006 00:00 The possibility of using electrons' spins in addition to their charge in information technology has created much enthusiasm for a new field of electronics popularly known as "spintronics." An intensely studied approach to obtaining spin-polarized carriers for data-storage devices is the use of diluted magnetic semiconductors created by doping ions like Mn, Fe, or Co having a net spin into a semiconducting host such as GaAs, ZnO, or GaN. The interaction among these spins leads to ferromagnetic order at low temperatures, which is necessary to create spin-polarized carriers. A research team working at ALS Beamline 4.0.2 and European Synchrotron Radiation Facility Beamline ID8 made a big leap forward in clarifying the microscopic picture of magnetism and anisotropy in Mn-doped GaAs by resolving localized and hybridized d states using angle-dependent x-ray magnetic circular dichroism (XMCD) measurements.
EIS-0281; Sandia National Laboratories/New Mexico, Draft Site-Wide Environmental Impact Statement
Organization of the Site-Wide Environmental Impact Statement Organization of the Site-Wide Environmental Impact Statement The Site-Wide Environmental Impact Statement (SWEIS) is divided into a Summary and two volumes. The Summary provides an overview of material presented in the SWEIS, including background, purpose and need, alternatives, existing environment, and environmental impacts. Volume I analyzes the three alternatives (including the No Action Alternative) as they relate to U.S. Department of Energy (DOE) missions assigned to Sandia National Laboratories/New Mexico (SNL/NM): national security, energy resources, environmental quality, science and technology. Volume I contains 15 chapters. Chapter 1 provides introductory information on background, site missions, purpose and need, decisions to be made, related National Environmental Policy Act analyses, and public participation. Chapter 2
Applicant Organization:
Iogen Biorefinery Partners, LLC Iogen Biorefinery Partners, LLC Corporate HQ: Arlington, VA Proposed Facility Location: Shelley, Idaho Description: This project from a leading enzyme player will demonstrate a scaled up biochemical process with the flexibility to process a wide range of agricultural residues into cellulose ethanol. CEO or Equivalent: Brian Foody Participants: Iogen Corporation, Goldman Sachs; Royal Dutch Shell Oil Company; Others Production: * 18 million gallons/year in the first plant, 250 million gallons/year in future plants * Cellulose ethanol & co-products in first plant; future plants to be primarily cellulose ethanol Technology & Feedstocks: * Agricultural residues: wheat straw, barley straw, corn stover, switchgrass and rice
Magnetism of Semiconductor-Based Magnetic Tunnel Junctions under Electric Field from First Principles
Semiconductor magnetic tunnel junctions (MTJs), composed of diluted magnetic semiconductors (DMSs) sandwiching a semiconductor barrier, have potential applications in spintronics but their development has been slow due to the difficulty of controlling the magnetism of DMSs. In terms of density functional calculations for model semiconductor MTJs, (Zn,Co)O/ZnO/(Zn,Co)O and (Ga,Mn)N/GaN/(Ga,Mn)N, we show that the magnetic coupling between the transition metal ions in each DMS electrode of such semiconductor MTJs can be switched from ferromagnetic to antiferromagnetic, or vice versa, under the application of external electric field across the junctions. Our results suggest a possible avenue for the application of semiconductor MTJs.
Kan, E.; Xiang, H.; Yang, J.; Whangbo, M. H.
Wide Area and Distributed Hydrogen Sensors
Recent advances in optical sensors show promise for the development of new wide area monitoring and distributed optical network hydrogen detection systems. Optical hydrogen sensing technologies reviewed here are: 1) open path Raman scattering systems, 2) back scattering from chemically treated solid polymer matrix optical fiber sensor cladding; and 3) shlieren and shearing interferometry imaging. Ultrasonic sensors for hydrogen release detection are also reviewed. The development status of these technologies and their demonstrated results in sensor path length, low hydrogen concentration detection ability, and response times are described and compared to the corresponding status of hydrogen spot sensor network technologies.
Zalosh, Robert G.; Barilo, Nick F.
Applicant Organization: | Department of Energy
Applicant Organization: Applicant Organization: Applicant Organization: More Documents & Publications BlueFire Ethanol, Inc. Applicant Organization: Applicant Organization:...
EIS-0387: Draft Site-Wide Environmental Impact Statement | Department of
Draft Site-Wide Environmental Impact Statement Draft Site-Wide Environmental Impact Statement EIS-0387: Draft Site-Wide Environmental Impact Statement Y-12 National Security Complex, Oak Ridge, TN The NNSA, a separately organized agency within the DOE, has the responsibility to maintain the safety, reliability, and security of the U.S. nuclear weapons stockpile to meet national security requirements. NNSA manages nuclear weapons programs and facilities, including those at the Y-12 National Security Complex (Y-12) at Oak Ridge, Tennessee. This Draft Y-12 SWEIS analyzes the potential environmental impacts of reasonable alternatives for ongoing and foreseeable future operations, facilities, and activities at Y-12. EIS-0387-DEIS-Summary-2009.pdf Draft Site-Wide Environmental Impact Statement for the Y-12 National
EIS-0426: DOE Notice of Availability of the Draft Site-Wide Environmental
DOE Notice of Availability of the Draft Site-Wide DOE Notice of Availability of the Draft Site-Wide Environmental Impact Statement and Notice of Public Hearings EIS-0426: DOE Notice of Availability of the Draft Site-Wide Environmental Impact Statement and Notice of Public Hearings Continued Operation of the Nevada National Security Site and Off-Site Locations in the State of Nevada The National Nuclear Security Administration (NNSA), a separately organized semi-autonomous agency within the U.S. Department of Energy (DOE), announces the availability of the Draft Site-Wide Environmental Impact Statement for the Continued Operation of the Department of Energy/National Nuclear Security Administration Nevada National Security Site and Off-Site Locations in the State of Nevada (Draft SWEIS, DOE/EIS-0426D) for public review, as well as the locations, dates and
Coherent multi-exciton dynamics in semiconductor nanostructures via two-dimensional Fourier transform optical spectroscopy
The Coulomb correlations between photoexcited charged particles in materials such as photosynthetic complexes, conjugated polymer systems, J-aggregates, and bulk or nanostructured semiconductors produce a hierarchy of ...
Stone, Katherine Walowicz
Comment on "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"
This is a comment on PRL paper by A.P. Kirk "Analysis of quantum coherent semiconductor quantum dot p-i-n junction photovoltaic cells"
Scully, Marlan O
Generic process for preparing a crystalline oxide upon a group IV semiconductor substrate
A process for growing a crystalline oxide epitaxially upon the surface of a Group IV semiconductor, as well as a structure constructed by the process, is described. The semiconductor can be germanium or silicon, and the crystalline oxide can generally be represented by the formula (AO).sub.n (A'BO.sub.3).sub.m in which "n" and "m" are non-negative integer repeats of planes of the alkaline earth oxides or the alkaline earth-containing perovskite oxides. With atomic level control of interfacial thermodynamics in a multicomponent semiconductor/oxide system, a highly perfect interface between a semiconductor and a crystalline oxide can be obtained.
McKee, Rodney A. (Kingston, TN); Walker, Frederick J. (Oak Ridge, TN); Chisholm, Matthew F. (Oak Ridge, TN)
Development of fluorescent semi-conductor nanocrystal conjugates for in vitro and in vivo imaging applications
Semiconductor nanocrystals, also known as quantum dots (QDs), are promising imaging probes with characteristic optical properties: tunable bandgap from visible to infrared, narrow and symmetric emission features, broad ...
Han, Hee-Sun, Ph. D. Massachusetts Institute of Technology
Global product development in semiconductor industry : Intel -- Tick-Tock product development cadence
This thesis investigates on changes in semiconductor industry's product development methodology by following Intel's product development from year 2000. Intel was challenged by customer's preference change, competitors new ...
Park, Cheolmin, S.M. Massachusetts Institute of Technology
Frequency modulation on single sideband using controlled dynamics of an optically injected semiconductor laser
locked semicon- ductor lasers with delayed optoelectronicgeneration using semiconductor laser dynamics,� IEEE J. Sel.in optically-injected laser diodes,� Opt. Commun. , vol.
Chan, Sze-Chun; Liu, Jia-Ming
Group I-III-VI.sub.2 semiconductor films for solar cell application
This invention relates to an improved thin film solar cell with excellent electrical and mechanical integrity. The device comprises a substrate, a Group I-III-VI.sub.2 semiconductor absorber layer and a transparent window layer. The mechanical bond between the substrate and the Group I-III-VI.sub.2 semiconductor layer is enhanced by an intermediate layer between the substrate and the Group I-III-VI.sub.2 semiconductor film being grown. The intermediate layer contains tellurium or substitutes therefor, such as Se, Sn, or Pb. The intermediate layer improves the morphology and electrical characteristics of the Group I-III-VI.sub.2 semiconductor layer.
Basol, Bulent M. (Redondo Beach, CA); Kapur, Vijay K. (Northridge, CA)
Table 4-3 Site Wide Environmental Management Matrix
Site-Wide Environmental Assessment of Table 4-3. Site-Wide Environmental Management Matrix National Renewable Energy Laboratory's South Table Mountain Complex FINAL POTENTIAL...
Government-Wide Diversity and Inclusion Strategic Plan (2011...
Government-Wide Diversity and Inclusion Strategic Plan (2011), Office of Personnel Management Government-Wide Diversity and Inclusion Strategic Plan (2011), Office of Personnel...
Implications of Wide-Area Geographic Diversity for Short- Term...
Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar Power Title Implications of Wide-Area Geographic Diversity for Short- Term Variability of Solar...
Plant Wide Assessment for SIFCO Industries, Inc.
Sifco Industries carreid out a plant wide energy assessment under a collaborative program with the U.S. Department of Energy during October 2004 to September 2005. During the year, personnel from EIS, E3M, DPS, BuyCastings.Com, and Sifco plant facilities and maintenance personnel, as a team collected energy use, construction, process, equipment and operational information about the plant. Based on this information, the team identified 13 energy savings opportunities. Near term savings opportunities have a total potential savings of about $1,329,000 per year and a combined simple payback of about 11 months. Implementation of these recommendations would reduce CO2 emissions by about 16,000,000 pounds per year, which would reduce overall plant CO2 emissions by about 45%. These totals do not include another $830,000 per year in potential savings with an estimated 9-month payback, from converting the forging hammers from steam to compressed air.
Kelly Kissock, Arvind Thekdi et. al.
Activation of molecular catalysts using semiconductor quantum dots
Photocatalytic materials based on coupling of semiconductor nanocrystalline quantum dots (NQD) and molecular catalysts. These materials have capability to drive or catalyze non-spontaneous chemical reactions in the presence of visible radiation, ultraviolet radiation, or both. The NQD functions in these materials as a light absorber and charge generator. Following light absorption, the NQD activates a molecular catalyst adsorbed on the surface of the NQD via transfer of one or more charges (either electrons or electron-holes) from the NQD to the molecular catalyst. The activated molecular catalyst can then drive a chemical reaction. A photoelectrolytic device that includes such photocatalytic materials is also described.
Meyer, Thomas J. (Chapel Hill, NC); Sykora, Milan (Los Alamos, NM); Klimov, Victor I. (Los Alamos, NM)
Light emission patterns from stadium-shaped semiconductor microcavity lasers
We study light emission patterns from stadium-shaped semiconductor (GaAs) microcavity lasers theoretically and experimentally. Performing systematic wave calculations for passive cavity modes, we demonstrate that the averaging by low-loss modes, such as those realized in multi-mode lasing, generates an emission pattern in good agreement with the ray model's prediction. In addition, we show that the dependence of experimental far-field emission patterns on the aspect ratio of the stadium cavity is well reproduced by the ray model.
Susumu Shinohara; Takehiro Fukushima; Takahisa Harayama
Three-terminal semiconductor laser for wave mixing
We suggest and analyze the concept of a semiconductor laser device that incorporates two basic ideas: (i) dual-wavelength generation of two optical fields on the interband transitions with independent control of each field in a three-terminal "transistor" scheme, and (ii) generation of infrared radiation in the 3-300 mum range due to nonlinear wave mixing of the above optical fields in the same laser cavity. Due to inversionless nature of the difference frequency generation and inherently low threshold current, the laser can be capable of continuous room-temperature operation in the mid/far-infrared and THz range.
Belyanin, Alexey; Kocharovsky, V.; Kocharovsky, V.; Scully, Marlan O.
Bistability of Cation Interstitials in II-VI Semiconductors
The stability of cation interstitials in II-VI semiconductors is studied using ab initio methods. We find that interstitials in the neutral charge state are more stable in the tetrahedral interstitial site near the cation, whereas in the (2+) charge state, they are more stable near the anion. The diffusion energy barrier changes when the defect charge state changes. Therefore, if electrons/holes are taken from the defect level by light, changing its charge state, the interstitial atom will be able to diffuse almost spontaneously due to a reduced diffusion barrier.
Wei, S. H.; Dalpian, G. M.
Ultrafast shift and injection currents observed in wurtzite semiconductors via emitted terahertz radiation
and injection currents have been generated in bulk GaAs and strained GaAs quantum wells QWs , respectivelyUltrafast shift and injection currents observed in wurtzite semiconductors via emitted terahertz; published online 18 November 2005 Shift and injection currents are generated in the wurtzite semiconductors
Van Driel, Henry M.
Density-gradient theory: a macroscopic approach to quantum confinement and tunneling in semiconductor devices
Density-gradient theory provides a macroscopic approach to modeling quantum transport that is particularly well adapted to semiconductor device analysis and engineering. After some introductory observations, the basis of the theory in macroscopic and ... Keywords: Continuum, Density-gradient, Electron transport, Quantum confinement, Quantum tunneling, Semiconductor device simulation, Thermodynamics
M. G. Ancona
Spin-polarized current oscillations in diluted magnetic semiconductor multiple quantum wells Manuel Bejar,1
Spin-polarized current oscillations in diluted magnetic semiconductor multiple quantum wells Manuel and charge dynamics of electrons in n-doped II-VI semiconductor multiple quantum wells when one or more quantum wells are doped with Mn. The interplay between strongly nonlinear interwell charge transport
Sánchez, David
Spline regression based feature extraction for semiconductor process fault detection using support vector machine
Quality control is attracting more attention in semiconductor market due to harsh competition. This paper considers Fault Detection (FD), a well-known philosophy in quality control. Conventional methods, such as non-stationary SPC chart, PCA, PLS, and ... Keywords: Fault detection, Feature extraction, Semiconductor manufacturing, Spline regression, Support vector machine
Jonghyuck Park; Ick-Hyun Kwon; Sung-Shick Kim; Jun-Geol Baek
Organo Luminescent semiconductor nanocrystal probes for biological applications and process for making and using such probes
A luminescent semiconductor nanocrystal compound is described which is capable of linking to an affinity molecule. The compound comprises (1) a semiconductor nanocrystal capable of emitting electromagnetic radiation (luminescing) in a narrow wavelength band and/or absorbing energy, and/or scattering or diffracting electromagnetic radiation--when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam; and (2) at least one linking agent, having a first portion linked to the semiconductor nanocrystal and a second portion capable of linking to an affinity molecule. The luminescent semiconductor nanocrystal compound is linked to an affinity molecule to form an organo luminescent semiconductor nanocrystal probe capable of bonding with a detectable substance in a material being analyzed, and capable of emitting electromagnetic radiation in a narrow wavelength band and/or absorbing, scattering, or diffracting energy when excited by an electromagnetic radiation source (of narrow or broad bandwidth) or a particle beam. The probe is stable to repeated exposure to light in the presence of oxygen and/or other radicals. Further described is a process for making the luminescent semiconductor nanocrystal compound and for making the organo luminescent semiconductor nanocrystal probe comprising the luminescent semiconductor nanocrystal compound linked to an affinity molecule capable of bonding to a detectable substance. A process is also described for using the probe to determine the presence of a detectable substance in a material.
Performance of a parallel algebraic multilevel preconditioner for stabilized finite element semiconductor device modeling
In this study results are presented for the large-scale parallel performance of an algebraic multilevel preconditioner for solution of the drift-diffusion model for semiconductor devices. The preconditioner is the key numerical procedure determining ... Keywords: Drift-diffusion, Finite element, Graph partitioning, Multigrid, Multilevel preconditioners, Newton-Krylov, Nonsmoothed aggregation, Schwarz domain decomposition, Semiconductor devices
Paul T. Lin; John N. Shadid; Marzio Sala; Raymond S. Tuminaro; Gary L. Hennigan; Robert J. Hoekstra
Using the FDM and ANP to construct a sustainability balanced scorecard for the semiconductor industry
This paper proposed a sustainability balanced scorecard (SBSC) framework to measure the sustainable performance of the semiconductor industry. Based on the principle of four perspectives of balanced scorecard (BSC), of which two were changed from the ... Keywords: Analytic network process, Fuzzy Delphi method, Semiconductor industry, Sustainability balanced scorecard
Chia-Wei Hsu; Allen H. Hu; Cherng-Ying Chiou; Ta-Che Chen
Reading Comprehension - Organs and Organ Systems
together in a group make up an organ system. Examples of organ systems are cats and dogs the circulatory system and the respiratory system the stomacular system and...
5 14:37 FR IPL DOE CH 630 252 2779 TO RGCP-HQ P.02/04 5 14:37 FR IPL DOE CH 630 252 2779 TO RGCP-HQ P.02/04 * * STATEMENT OF CONSIDERATIONS REQUEST BY OSRAM OPTO SEMICONDUCTORS FOR AN ADVANCE WAIVER OF DOMESTIC AND FOREIGN INVENTION RIGHTS UNDER DOE CONTRACT NO. DE-FC26-05NT42341, SUBCONTRACT QZ001; W(A)-05-017, CH-1280 The Petitioner, OSRAM Opto Semiconductor (Osram) was awarded a subcontract under this cooperative agreement for the performance of work entitled, "Scaling Up KiloLumen Solid- State Lighting Exceeding 100 LPW via Remote Phosphor." The cooperative agreement was awarded to Light Prescriptions Innovators, LLC (LPI). The purpose of the cooperative agreement is to develop a new white light emitting diode (LED) light source that emits 1000 lumens with an efficacy exceeding 100 lumens per watt (LPW). The new white LED light source will use multiple
Characterization of Hydrogen Complex Formation in III-V Semiconductors
Atomic hydrogen has been found to react with some impurity species in semiconductors. Hydrogenation is a methodology for the introduction of atomic hydrogen into the semiconductor for the express purpose of forming complexes within the material. Efforts to develop hydrogenation as an isolation technique for AlGaAs and Si based devices failed to demonstrate its commercial viability. This was due in large measure to the low activation energies of the formed complexes. Recent studies of dopant passivation in long wavelength (0.98 - 1.55?m) materials suggested that for the appropriate choice of dopants much higher activation energies can be obtained. This effort studied the formation of these complexes in InP, This material is extensively used in optoelectronics, i.e., lasers, modulators and detectors. The experimental techniques were general to the extent that the results can be applied to other areas such as sensor technology, photovoltaics and to other material systems. The activation energies for the complexes have been determined and are reported in the scientific literature. The hydrogenation process has been shown by us to have a profound effect on the electronic structure of the materials and was thoroughly investigated. The information obtained will be useful in assessing the long term reliability of device structures fabricated using this phenomenon and in determining new device functionalities.
Williams, Michael D.
High-efficiency photovoltaics based on semiconductor nanostructures
The objective of this project was to exploit a variety of semiconductor nanostructures, specifically semiconductor quantum wells, quantum dots, and nanowires, to achieve high power conversion efficiency in photovoltaic devices. In a thin-film device geometry, the objectives were to design, fabricate, and characterize quantum-well and quantum-dot solar cells in which scattering from metallic and/or dielectric nanostructures was employed to direct incident photons into lateral, optically confined paths within a thin (~1-3um or less) device structure. Fundamental issues concerning nonequilibrium carrier escape from quantum-confined structures, removal of thin-film devices from an epitaxial growth substrate, and coherent light trapping in thin-film photovoltaic devices were investigated. In a nanowire device geometry, the initial objectives were to engineer vertical nanowire arrays to optimize optical confinement within the nanowires, and to extend this approach to core-shell heterostructures to achieve broadspectrum absorption while maintaining high opencircuit voltages. Subsequent work extended this approach to include fabrication of nanowire photovoltaic structures on low-cost substrates.
Yu, Paul K.L. [University of California, San Diego; Yu, Edward T. [University of Texas at Austin; Wang, Deli [University of California, San Diego
Helicon wave excitation to produce energetic electrons for manufacturing semiconductors
A helicon plasma source is controlled by varying the axial magnetic field or rf power controlling the formation of the helicon wave. An energetic electron current is carried on the wave when the magnetic field is 90 G; but there is minimal energetic electron current when the magnetic field is 100 G in one particular plasma source. Similar performance can be expected from other helicon sources by properly adjusting the magnetic field and power to the particular geometry. This control for adjusting the production of energetic electrons can be used in the semiconductor and thin-film manufacture process. By applying energetic electrons to the insulator layer, such as silicon oxide, etching ions are attracted to the insulator layer and bombard the insulator layer at higher energy than areas that have not accumulated the energetic electrons. Thus, silicon and metal layers, which can neutralize the energetic electron currents will etch at a slower or non-existent rate. This procedure is especially advantageous in the multilayer semiconductor manufacturing because trenches can be formed that are in the range of 0.18--0.35 mm or less. 16 figs.
Molvik, A.W.; Ellingboe, A.R.
Femtosecond laser interactions with semiconductor and dielectric materials
Electronic excitation-relaxation processes induced by ultra-short laser pulses are studied numerically for semiconductors and dielectric materials (Si, quartz). A detailed kinetic approach is used in the calculations accounting for electron-photon-phonon, electron-phonon and electron-electron scatterings. In addition, both laser field ionization ranging from multi-photon to tunneling one, and electron impact (avalanche) ionization processes are included in the model. Based on the performed calculations we study the relaxation time as a function of laser parameters. It is shown that this time depends on the density of the created free carriers, which in turn is a nonlinear function of laser intensity. In addition, a simple damage criterion is proposed based on the mean electron energy density rather than on critical free electron density. This criterion gives a reasonable agreement with the available experimental data practically without adjustable parameters. Furthermore, the performed modeling provides energy absorbed in the target, conditions for damage of dielectric materials, as well as conditions for surface plasmon excitation and for periodic surface structure formation on the surface of semiconductor materials.
Shcheblanov, Nikita S.; Derrien, Thibault J. Y.; Itina, Tatiana E. [Laboratoire Hubert Curien, CNRS//Universite Jeann Monnet, 18 rue du Prof. Benoit Lauras, 42000 Saint-Etienne (France); Laboratoire Lasers, Plasmas et Procedes Photoniques, CNRS//Universite de la Mediterranee, 162 avenue de Luminy, 13288, Marseille (France); Laboratoire Hubert Curien, CNRS//Universite Jeann Monnet, 18 rue du Prof. Benoit Lauras, 42000 Saint-Etienne (France)
Synthesis and catalytic properties of metal and semiconductor nanoclusters
Synthesis of metal or semiconductor nanoclusters in microheterogeneous oil-continuous inverse micelle systems is discussed. We focus on synthesis and catalytic properties of palladium, iron, and iron sulfide nanoclusters. Cluster size-control is achieved by changing the micelle size which is determined by small angle neutron scattering (SANS) and chosen to produce cluster in size range of 1-20 nm. Cluster sizes were determined by either transmission electron microscopy (TEM) or small-angle x-ray scattering (SAXS). Cluster structure was determined by either x-ray or electron diffraction. In the case of Fe nanoclusters the crystal structure depended on the chemical nature of the surfactant micelle used in the synthesis, illustrating the important role of the surfactant during the growth process. Results of in-situ pyrene hydrogenation using size-selected Pd clusters show a significant increase in activity/total surface area as the size decreases. These clusters also proved effective as unsupported catalysts for direct coal hydropyrolysis, even at very low metal concentrations. Synthesis and optical features of a new semiconductor cluster material, FeS{sub 2}, is discussed with regard to its use in photocatalysis. Application of FeS{sub 2} in coal hydrogenolysis reactions has improved yields of short chain hydrocarbons significantly compared to conventional FeS{sub 2} powders.
Wilcoxon, J.P.; Martino, T.; Klavetter, E.; Sylwester, A.P.
Low-temperature magnetization of (Ga,Mn) As semiconductors
We report on a comprehensive study of the ferromagnetic moment per Mn atom in (Ga,Mn)As ferromagnetic semiconductors. Theoretical discussion is based on microscopic calculations and on an effective model of Mn local moments antiferromagnetically coupled to valence band hole spins. The validity of the effective model over the range of doping studied is assessed by comparing with microscopic tight-binding/coherent-potential approximation calculations. Using the virtual crystal k center dot p model for hole states, we evaluate the zero-temperature mean-field contributions to the magnetization from the hole kinetic and exchange energies, and magnetization suppression due to quantum fluctuations of Mn moment orientations around their mean-field ground state values. Experimental low-temperature ferromagnetic moments per Mn are obtained by superconducting quantum interference device and x-ray magnetic circular dichroism measurements in a series of (Ga,Mn)As semiconductors with nominal Mn doping ranging from similar to 2 to 8%. Hall measurements in as-grown and annealed samples are used to estimate the number of uncompensated substitutional Mn moments. Based on our comparison between experiment and theory we conclude that all these Mn moments in high quality (Ga,Mn)As materials have nearly parallel ground state alignment.
Jungwirth, T.; Masek, J.; Wang, KY; Edmonds, KW; Sawicki, M.; Polini, M.; Sinova, Jairo; MacDonald, AH; Campion, RP; Zhao, LX; Farley, NRS; Johal, TK; van der Laan, G.; Foxon, CT; Gallagher, BL.
Method and apparatus for thermal processing of semiconductor substrates
An improved apparatus and method for thermal processing of semiconductor wafers. The apparatus and method provide the temperature stability and uniformity of a conventional batch furnace as well as the processing speed and reduced time-at-temperature of a lamp-heated rapid thermal processor (RTP). Individual wafers are rapidly inserted into and withdrawn from a furnace cavity held at a nearly constant and isothermal temperature. The speeds of insertion and withdrawal are sufficiently large to limit thermal stresses and thereby reduce or prevent plastic deformation of the wafer as it enters and leaves the furnace. By processing the semiconductor wafer in a substantially isothermal cavity, the wafer temperature and spatial uniformity of the wafer temperature can be ensured by measuring and controlling only temperatures of the cavity walls. Further, peak power requirements are very small compared to lamp-heated RTPs because the cavity temperature is not cycled and the thermal mass of the cavity is relatively large. Increased speeds of insertion and/or removal may also be used with non-isothermal furnaces.
Griffiths, Stewart K. (Danville, CA); Nilson, Robert H. (Cardiss, CA); Mattson, Brad S. (Los Gatos, CA); Savas, Stephen E. (Alameda, CA)
Argonne CNM News: State-of-the-Art Diamond Semiconductor Technology
State-of-the-Art Diamond Semiconductor Technology Licensed to AKHAN Technologies State-of-the-Art Diamond Semiconductor Technology Licensed to AKHAN Technologies The U.S. Department of Energy's Argonne National Laboratory announced today that the laboratory has granted AKHAN Technologies, Inc., exclusive diamond semiconductor application licensing rights to breakthrough low-temperature diamond deposition technology developed by Argonne's Center for Nanoscale Materials (CNM). The method allows for the deposition of nanocrystalline diamond on a variety of wafer substrate materials at temperatures as low as 400°C, highly advantageous for integration with processed semiconductor electronic materials and resulting in the deposition of low-defect nanocrystalline diamond (NCD) thin films. The combination of CNM's low-temperature diamond technology with the AKHAN Miraj Diamond(tm) process represents the state of the art in diamond semiconductor thin-film technology.
Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction: Utility Application Guideline
This CD provides guidance from the EPRI initiative on IC Strategies for Plant-Wide and Fleet-Wide Cost Reduction. Included on the CD are EPRI Technical Report 1015087, Instrumentation and Control Strategies for Plant-Wide and Fleet-Wide Cost Reduction: Utility Application Guideline, published October 2007, and two multimedia briefings. The report and briefings describe a wide range of options while emphasizing integrated modernization across the plant or fleet. Coordinated improvements to shared communi...
Flow-Solution-Liquid-Solid Growth of Semiconductor Nanowires: A Novel Approach for Controlled Synthesis
Semiconductor nanowires (SC-NWs) have potential applications in diverse technologies from nanoelectronics and photonics to energy harvesting and storage due to their quantum-confined opto-electronic properties coupled with their highly anisotropic shape. Here, we explore new approaches to an important solution-based growth method known as solution-liquid-solid (SLS) growth. In SLS, molecular precursors are reacted in the presence of low-melting metal nanoparticles that serve as molten fluxes to catalyze the growth of the SC-NWs. The mechanism of growth is assumed to be similar to that of vapor-liquid-solid (VLS) growth, with the clear distinctions of being conducted in solution in the presence of coordinating ligands and at relatively lower temperatures (<300 C). The resultant SC-NWs are soluble in common organic solvents and solution processable, offering advantages such as simplified processing, scale-up, ultra-small diameters for quantum-confinement effects, and flexible choice of materials from group III-V to groups II-VI, IV-VI, as well as truly ternary I-III-VI semiconductors as we recently demonstrates. Despite these advantages of SLS growth, VLS offers several clear opportunities not allowed by conventional SLS. Namely, VLS allows sequential addition of precursors for facile synthesis of complex axial heterostructures. In addition, growth proceeds relatively slowly compared to SLS, allowing clear assessments of growth kinetics. In order to retain the materials and processing flexibility afforded by SLS, but add the elements of controlled growth afforded by VLS, we transformed SLS into a flow based method by adapting it to synthesis in a microfluidic system. By this new method - so-called 'flow-SLS' (FSLS) - we have now demonstrated unprecedented fabrication of multi-segmented SC-NWs, e.g., 8-segmented CdSe/ZnSe defined by either compositionally abrupt or alloyed interfaces as a function of growth conditions. In addition, we have studied growth rates as a function of catalyst size/SC-NW diameter and shown for the first time that SLS is governed by Gibbs-Thomson effects. Lastly, from an applications standpoint, we report growth of SC-NWs from a range of substrates, including ITO-coated glass for fabrication of hybrid photovoltaic devices, comparing these to their quasi zero-dimensional quantum-dot counterparts.
Hollingsworth, Jennifer A. [Los Alamos National Laboratory; Palaniappan, Kumaranand [Los Alamos National Laboratory; Laocharoensuk, Rawiwan [National Science and Technology Center, Thailand; Smith, Nickolaus A. [Los Alamos National Laboratory; Dickerson, Robert M. [Los Alamos National Laboratory; Casson, Joanna L. [Los Alamos National Laboratory; Baldwin, Jon K. [Los Alamos National Laboratory
Recyclable Sorbent Coating for Organic Pollutant Sampler
Ion Sources with Antennas; Semiconductor and Other Manufacturing; Ion Source and Beam Tools; Nano- & Micro-technology; Software and IT ;
EIS-0387: Final Site-Wide Environmental Impact Statement | Department of
Final Site-Wide Environmental Impact Statement Final Site-Wide Environmental Impact Statement EIS-0387: Final Site-Wide Environmental Impact Statement Y-12 National Security Complex Project, Oak Ridge, TN NNSA, a separately organized agency within DOE, is responsible for maintaining the safety, reliability, and security of the U.S. nuclear weapons stockpile to meet national security requirements. NNSA manages nuclear weapons programs and facilities, including those at the Y-12 National Security Complex (Y-12) at Oak Ridge, Tennessee. This Final Y-12 SWEIS analyzes the potential environmental impacts of the reasonable alternatives for ongoing and foreseeable future operations and activities at Y-12, including alternatives for changes to site infrastructure and levels of operation (using production capacity as the key metric for
EIS-0387: Y-12 National Security Complex Site-Wide Environmental Impact
87: Y-12 National Security Complex Site-Wide Environmental 87: Y-12 National Security Complex Site-Wide Environmental Impact Statement, Oak Ridge, Tennessee EIS-0387: Y-12 National Security Complex Site-Wide Environmental Impact Statement, Oak Ridge, Tennessee Overview NNSA, a separately organized agency within DOE, is responsible for maintaining the safety, reliability, and security of the U.S. nuclear weapons stockpile to meet national security requirements. NNSA manages nuclear weapons programs and facilities, including those at the Y-12 National Security Complex (Y-12) at Oak Ridge, Tennessee. This Final Y-12 SWEIS analyzed the potential environmental impacts of the reasonable alternatives for ongoing and foreseeable future operations and activities at Y-12, including alternatives for changes to site infrastructure and
WorldWideScience.org: China's Participation Expands Access to...
International Council for Scientific and Technical Information (ICSTI), which serves as a primary sponsor of the WorldWideScience Alliance. WorldWideScience.org was conceived and...
Wide electrochemical window solvents for use in electrochemical ...
Wide electrochemical window solvents for use in electrochemical devices and electrolyte solutions incorporating such solvents United States Patent
System for characterizing semiconductor materials and photovoltaic devices through calibration
A method and apparatus for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby.
Sopori, Bhushan L. (Denver, CO); Allen, Larry C. (Arvada, CO); Marshall, Craig (Littleton, CO); Murphy, Robert C. (Golden, CO); Marshall, Todd (Littleton, CO)
Improved Thermoelectric Devices: Advanced Semiconductor Materials for Thermoelectric Devices
Broad Funding Opportunity Announcement Project: Phononic Devices is working to recapture waste heat and convert it into usable electric power. To do this, the company is using thermoelectric devices, which are made from advanced semiconductor materials that convert heat into electricity or actively remove heat for refrigeration and cooling purposes. Thermoelectric devices resemble computer chips, and they manage heat by manipulating the direction of electrons at the nanoscale. These devices aren�t new, but they are currently too inefficient and expensive for widespread use. Phononic Devices is using a high-performance, cost-effective thermoelectric design that will improve the device�s efficiency and enable electronics manufacturers to more easily integrate them into their products.
Standard practice for radiologic examination of semiconductors and electronic components
1.1 This practice provides the minimum requirements for nondestructive radiologic examination of semiconductor devices, microelectronic devices, electromagnetic devices, electronic and electrical devices, and the materials used for construction of these items. 1.2 This practice covers the radiologic examination of these items to detect possible defective conditions within the sealed case, especially those resulting from sealing the lid to the case, and internal defects such as extraneous material (foreign objects), improper interconnecting wires, voids in the die attach material or in the glass (when sealing glass is used) or physical damage. 1.3 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this practice. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the app...
American Society for Testing and Materials. Philadelphia
Band engineering in dilute nitride and bismide semiconductor lasers
Highly mismatched semiconductor alloys such as GaNAs and GaBiAs have several novel electronic properties, including a rapid reduction in energy gap with increasing x and also, for GaBiAs, a strong increase in spin orbit- splitting energy with increasing Bi composition. We review here the electronic structure of such alloys and their consequences for ideal lasers. We then describe the substantial progress made in the demonstration of actual GaInNAs telecomm lasers. These have characteristics comparable to conventional InP-based devices. This includes a strong Auger contribution to the threshold current. We show, however, that the large spin-orbit-splitting energy in GaBiAs and GaBiNAs could lead to the suppression of the dominant Auger recombination loss mechanism, finally opening the route to e?fficient temperature-stable telecomm and longer wavelength lasers with significantly reduced power consumption.
Christopher A. Broderick; Muhammad Usman; Stephen J. Sweeney; Eoin P. O'Reilly
GaN Metal Oxide Semiconductor Field Effect Transistors
A GaN based depletion mode metal oxide semiconductor field effect transistor (MOSFET) was demonstrated using Ga{sub 2}O{sub 3}(Gd{sub 2}O{sub 3}) as the gate dielectric. The MOS gate reverse breakdown voltage was > 35V which was significantly improved from 17V of Pt Schottky gate on the same material. A maximum extrinsic transconductance of 15 mS/mm was obtained at V{sub ds} = 30 V and device performance was limited by the contact resistance. A unity current gain cut-off frequency, f{sub {tau}}, and maximum frequency of oscillation, f{sub max} of 3.1 and 10.3 GHz, respectively, were measured at V{sub ds} = 25 V and V{sub gs} = {minus}20 V.
Ren, F.; Pearton, S.J.; Abernathy, C.R.; Baca, A.; Cheng, P.; Shul, R.J.; Chu, S.N.G.; Hong, M.; Lothian, J.R.; Schurman, M.J.
A method and apparatus are disclosed for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby. 44 figs.
Sopori, B.L.; Allen, L.C.; Marshall, C.; Murphy, R.C.; Marshall, T.
Predicted Ultrafast Single Qubit Operations in Semiconductor Quantum Dots
Several recently proposed implementations of scalable quantum computation rely on the ability to manipulate the spin polarization of individual electrons in semiconductors. The most rapid single-spin-manipulation technique to date relies on the generation of an effective magnetic field via a spin-sensitive optical Stark effect. This approach has been used to split spin states in colloidal CdSe quantum dots and to manipulate ensembles of spins in ZnMnSe quantum wells with femtosecond optical pulses. Here we report that the process will produce a coherent rotation of spin in quantum dots containing a single electron. The calculated magnitude of the effective magnetic field depends on the dot bandgap and the strain. We predict that in InAs/InP dots, for reasonable experimental parameters, the magnitude of the rotation is sufficient and the intrinsic error is low enough for them to serve as elements of a quantum dot based quantum computer.
C. E. Pryor; M. E. Flatt�
Active RF Pulse Compression Using An Electrically Controlled Semiconductor Switch
First we review the theory of active pulse compression systems using resonant delay lines. Then we describe the design of an electrically controlled semiconductor active switch. The switch comprises an active window and an overmoded waveguide three-port network. The active window is based on a four-inch silicon wafer which has 960 PIN diodes. These are spatially combined in an overmoded waveguide. We describe the philosophy and design methodology for the three-port network and the active window. We then present the results of using this device to compress 11.4 GHz RF signals with high compression ratios. We show how the system can be used with amplifier like sources, in which one can change the phase of the source by manipulating the input to the source. We also show how the active switch can be used to compress a pulse from an oscillator like sources, which is not possible with passive pulse compression systems.
Guo, Jiquan; Tantawi, Sami; /SLAC
Subtle Chemistry of Colloidal, Quantum-Confined Semiconductor Nanostructures
Nanoscale colloidal semiconductor structures with at least one dimension small enough to experience quantum confinement effects have captured the imagination and attention of scientists interested in controlling various chemical and photophysical processes. Aside from having desirable quantum confinement properties, colloidal nanocrystals are attractive because they are often synthesized in low-temperature, low-cost, and potentially scalable manners using simple benchtop reaction baths. Considerable progress in producing a variety of shapes, compositions, and complex structures has been achieved. However, there are challenges to overcome in order for these novel materials to reach their full potential and become new drivers for commercial applications. The final shape, composition, nanocrystal-ligand structure, and size can depend on a delicate interplay of precursors, surface ligands, and other compounds that may or may not participate in the reaction. In this Perspective, we discuss current efforts toward better understanding how the reactivity of the reagents can be used to produce unique and complex nanostructures.
Hughes, B. K.; Luther, J. M.; Beard, M. C.
High gain photoconductive semiconductor switch having tailored doping profile zones
A photoconductive semiconductor switch with tailored doping profile zones beneath and extending laterally from the electrical contacts to the device. The zones are of sufficient depth and lateral extent to isolate the contacts from damage caused by the high current filaments that are created in the device when it is turned on. The zones may be formed by etching depressions into the substrate, then conducting epitaxial regrowth in the depressions with material of the desired doping profile. They may be formed by surface epitaxy. They may also be formed by deep diffusion processes. The zones act to reduce the energy density at the contacts by suppressing collective impact ionization and formation of filaments near the contact and by reducing current intensity at the contact through enhanced current spreading within the zones.
Baca, Albert G. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Mar, Alan (Albuquerque, NM); Zutavern, Fred J (Albuquerque, NM); Hjalmarson, Harold P. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Zipperian, Thomas E. (Edgewood, NM); O' Malley, Martin W. (Edgewood, NM); Helgeson, Wesley D. (Albuquerque, NM); Denison, Gary J. (Sandia Park, NM); Brown, Darwin J. (Albuquerque, NM); Sullivan, Charles T. (Albuquerque, NM); Hou, Hong Q. (Albuquerque, NM)
Transforming the Lighting Sector with Semiconductor Lighting Technologies
17-TED-000924-9/27 SR#2000-2333C 17-TED-000924-9/27 SR#2000-2333C Transforming the Lighting Sector With Semiconductor Lighting Technologies Thomas Drennen Sandia National Laboratories Roland Haitz Agilent Technologies Jeffrey Tsao E20 Communications Sandia National Laboratories USAEE/IAEE Annual Meetings Philadelphia, PA September 24-27, 2000 Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL85000 2 6217-TED-000924-9/27 SR#2000-2333C Overview * Introduction * U.S. Lighting Demand * Evolution of LEDs * The LED Simulation Model (LEDSim) * Results 3 6217-TED-000924-9/27 SR#2000-2333C Introduction 0 50 100 150 200 1970 1980 1990 2000 2010 2020 Efficiency (lm/W) Year Incandescent Halogen Fluorescent Semi- conductor
FINITE DIFFERENCE METHODS FOR THE WIDE-ANGLE `PARABOLIC' EQUATION GEORGIOS AKRIVIS Abstract. We consider a model initial and boundary value problem for the wide-angle `parabolic' equation Lur = icu, the wide-angle `parabolic'equation of underwater acoustics. Given R > 0, µ 0, > 0, , and q real
Akrivis, Georgios
Methods of forming semiconductor devices and devices formed using such methods
Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.
Fox, Robert V; Rodriguez, Rene G; Pak, Joshua
The development of large area saturable Bragg reflectors for the generation of widely-tunable ultra-short pulses
This thesis focuses on the realization of two photonic devices; 1) semiconductor lasers and 2) large area broadband Saturable Bragg Reflectors (SBRs). Semiconductor lasers explore the use of 3D and 2D quantum confinement ...
Nabanja, Sheila P
White organic light-emitting diodes (OLEDs) are ultra-thin, large-area light sources made from organic semiconductor materials. Over the last decades, much research has been spent on finding the suitable materials to realize highly efficient monochrome and white OLEDs. With their high efficiency, color-tunability, and color-quality, white OLEDs are emerging to become one of the next generation light sources. In this review, we discuss the physics of a variety of device concepts that are introduced to realize white OLEDs based on both polymer and small molecule organic materi als. Owing to the fact that about 80 % of the internally generated photons are trapped within the thin-film layer structure, we put a second focus on reviewing promising concepts for improved light outcoupling.
Reineke, Sebastian; L�ssem, Bj�rn; Leo, Karl
Benefits of Site-wide NEPA Review | Department of Energy
Benefits of Site-wide NEPA Review Benefits of Site-wide NEPA Review Benefits of Site-wide NEPA Review The purpose of this guidance memorandum is to describe potential benefits of conducting a site-wide NEPA review (environmental impact statement or environmental assessment). I believe that this information will help program and field offices prepare their annual NEPA planning summaries and their overall NEPA compliance strategies. Site-wide reviews can aid the Department of Energy (DOE) in meeting its goals to streamline the NEPA process, to make that process more useful to decision makers and the public, and to reduce the time and cost required to prepare NEPA documents Benefits of Site-wide NEPA Review More Documents & Publications Benefits of Site-wide NEPA National Environmental Policy Act Review (1994)
Interconnection-Wide Transmission Planning Initiative: Topic A,
Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning A description of the requirements for Topic A for all Interconnections under the Interconnection-Wide Transmission Planning Initiative, part of the American Recovery and Reinvestment Act. Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning More Documents & Publications Microsoft Word - yDE-FOA-0000068.rtf Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Eastern Interconnection on Electric Resource Planning and Priorities Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation
will develop, fabricate, and fully characterize a 12-inch square OLED (Organic Light Emitting Diode) white light prototype. The prototype will be based on use of multiple discrete...
Colloidal semiconductor nanocrystals as nanoscale emissive probes in light emitting diodes and cell biology
This thesis employs colloidal semiconductor nanocrystals (NCs) as nanoscale emissive probes to investigate the physics of light emitting diodes (LEDs), as well as to unveil properties of cells that conventional imaging ...
Huang, Hao, Ph. D. Massachusetts Institute of Technology
Optical Probe for Semiconductor: Cooperative Research and Development Final Report, CRADA Number CRD-06-206
This CRADA involves development of a new semiconductor characterization tool, Optical Probe, which can be commercialized by GT Solar. GT Solar will participate in the design and testing of this instrument that will be developed under an IPP project.
Sopori, B.
Role of propagating ionisation fronts in semiconductor generation of sub-ps THz radiation
in standard semiconductor THz emitters may lead to identification of superior materials and excitation) 2806. [7] J.L. Oudar, D. Hulin, A. Migus, A. Antonetti, F. Alexandre, Phys. Rev. Lett. 55 (1985) 2074
Strathclyde, University of
Multivariable analysis of spectral measurements for the characterization of semiconductor processes
The availability of affordable and reliable optical sensor technology and the abundance of data that these sensors now provide have created new opportunities to better characterize and control semiconductor processes in ...
White, David A. (David Allan), 1966-
Prediction of semiconductor band edge positions in aqueous environments from first principles
The ability to predict a semiconductor's band edge positions in solution is important for the design of water-splitting photocatalyst materials. In this paper, we introduce a first-principles method to compute the ...
Wu, Yabi
Semiconductor-based all-optical switching for optical time-division multiplexed networks
All-optical switching will likely be required for future optical networks operating at data rates which exceed electronic processing speeds. Switches utilizing nonlinearities in semiconductor optical amplifiers (SOA) are ...
Robinson, Bryan S. (Bryan Shawn), 1975-
Semiconductors and sustainability : energy and materials use in integrated circuit manufacturing
Semiconductors have propelled an incredible revolution in the way we generate, access, store, and communicate information; the effects of this revolution have transformed culture, society, and the economy. At the same time, ...
Branham, Matthew S
Substrate engineering for monolithic integration of III-V semiconductors with Si CMOS technology
Ge virtual substrates, fabricated using Si1-xGex-.Ge, compositionally graded buffers, enable the epitaxial growth of device-quality GaAs on Si substrates, but monolithic integration of III-V semiconductors with Si CMOS ...
Dohrman, Carl Lawrence
Integer programming-based real-time scheduler in semiconductor manufacturing
This paper demonstrates how an integer programming-based real-time scheduling heuristic approach can be applied for semiconductor manufacturing. Two integer programming formulations of a simplified version of this problem are proposed to model (1) a ...
Myoungsoo Ham; Young Hoon Lee; John W. Fowler
Product strategy in response to technological innovation in the semiconductor test industry
After the market boom of 2000 in the semiconductor industry changed significantly. The changes included stricter limits on capital cost spending, and the increased propensity of the industry to outsource the manufacturing ...
Lin, Robert W. (Robert Wei-Pang), 1976-
X-ray and photoelectron spectroscopy of the structure, reactivity, and electronic structure of semiconductor nanocrystals
Figure 2-5 FESEM of 60� CdSe nanocrystals on hexanedithiol/properties of semiconductor (CdSe, InAs) nanocrystals andCdSe)..
Hamad, Kimberly S.
Dilute magnetic semiconductor Cu2FeSnS4 nanocrystals with a novel zincblende structure
Diluted magnetic semiconductor Cu2FeSnS4 nanocrystals with a novel zincblende structure have been successfully synthesized by a hot-injection approach. Cu+, Fe2+, and Sn4+ ions occupy the same position in the ...
Xiaolu Liang; Xianhua Wei; Daocheng Pan
The physics and chemistry of semiconductor nanocrystals in sol-gel derived optical microcavities
The incorporation of semiconductor nanocrystals (NCs) into sol-gel derived matrices presents both novel applications as well as a robust platform in which to investigate the nonlinear optical properties of NCs. This thesis ...
Chan, Yinthai
BAs-GaAs Semiconductor Alloys as a Photovoltaic Alternative to Nitride Alloys
Nitrogen alloyed III-V semiconductor compounds have been intensely studied in recent years due to unusual effects caused by nitrogen alloying. These effects are exploited in band gap engineering for specific applications such as solar cells and blue lasers.
Hart, G. L. W.; Zunger, A.
Spectroscopy and external control of optical dynamics in single semiconductor nanocrystals
Single molecule spectroscopy has progressed substantially in the past ten years and the accompanying progress in the optical study of single semiconductor nanocrystals has opened a new dimension in our understanding of the ...
Shimizu, Kentaro, 1975-
Dilute III-V Nitride Semiconductors and Material Systems: Physics and Technology, 1st edition
A major current challenge for semiconductor devices is to develop materials for the next generation of optical communication systems and solar power conversion applications. Recently, extensive research has revealed that an introduction of only a few ...
Ayse Erol; Ayse Erol
Semiconductor with protective surface coating and method of manufacture thereof. [Patent application
Passivation of predominantly crystalline semiconductor devices is provided for by a surface coating of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating of amorphous germanium onto the etched and quenched diode surface in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices, which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating compensates for pre-existing undesirable surface states as well as protecting the semiconductor device against future impregnation with impurities.
Hansen, W.L.; Haller, E.E.
Simple method for surface selective adsorption of semiconductor nanocrystals with nanometric resolution
Self-assembly methods play a major role in many modern fabrication techniques for various nanotechnology applications. In this paper we demonstrate two alternatives for self-assembled patterning within the nanoscale resolution of optically active semiconductor ...
O. Koslovsky, S. Yochelis, N. Livneh, M. G. Harats, R. Rapaport, Y. Paltiel
Growth of coincident site lattice matched semiconductor layers and devices on crystalline substrates
Methods of fabricating a semiconductor layer or device and said devices are disclosed. The methods include but are not limited to providing a substrate having a crystalline surface with a known lattice parameter (a). The method further includes growing a crystalline semiconductor layer on the crystalline substrate surface by coincident site lattice matched epitaxy, without any buffer layer between the crystalline semiconductor layer and the crystalline surface of the substrate. The crystalline semiconductor layer will be prepared to have a lattice parameter (a') that is related to the substrate lattice parameter (a). The lattice parameter (a') maybe related to the lattice parameter (a) by a scaling factor derived from a geometric relationship between the respective crystal lattices.
Norman, Andrew G; Ptak, Aaron J
Microwave frequency division and multiplication using an optically injected semiconductor laser
Senior Member of the IEEE Laser and Electro-Optics Society,modelocked semiconductor lasers,� Electron. Lett. , vol. 36,recovery by a ?ber ring laser employing a linear optical
Atomic-scale properties of semiconductor heterostructures probed by scanning tunneling microscopy
The engineering of advanced semiconductor heterostructure materials and devices requires a detailed understanding of, and control over, the structure and properties of semiconductor materials and devices at the atomic to nanometer scale. Cross-sectional scanning tunneling microscopy has emerged as a unique and powerful method to characterize structural morphology and electronic properties in semiconductor epitaxial layers and device structures at these length scales. The basic experimental techniques in cross-sectional scanning tunneling microscopy are described, and some representative applications to semiconductor heterostructure characterization drawn from recent investigations in the authors laboratory are discussed. Specifically, they describe some recent studies of InP/InAsP and InAsP/InAsSb heterostructures in which nanoscale compositional clustering has been observed and analyzed.
Yu, E.T.; Zuo, S.L.; Bi, W.G.; Tu, C.W. [Univ. of California, San Diego, La Jolla, CA (United States). Dept. of Electrical and Computer Engineering; Biefeld, R.M.; Allerman, A.A. [Sandia National Labs., Albuquerque, NM (United States)
Program management systems for the semiconductor processing capital equipment supply chain
The Capital Equipment Procurement group of Intel Corporation is responsible for developing and procuring the semiconductor processing capital equipment that is used throughout all of the company's development and manufacturing ...
Chandler, Thomas B. (Thomas Brian), 1970-
Ge-on-Si Integrated Photonics: New Tricks from an Old Semiconductor
We review recent progress in Ge active photonic devices for electronic-photonic integration on Si, demonstrating new tricks in optoelectronics from this �old� semiconductor material used for the first transistor more than ...
Jifeng, Liu
Application of RFID on equipment parts readiness management system of semiconductor packaging plant
Management of equipment parts readiness for process setup adjustment to meet variable order requirements in a semiconductor packaging plant is crucial to the health of production lines and downtime avoidance. In order to improve the current equipment ...
Wei-Ling Wang; Chiao-Tzu Huang; Shu-Jen Wang; Chia-Pao Chang; Hui-Wen Liao
Understanding How Semiconductors Absorb Light | U.S. DOE Office of Science
How Semiconductors Absorb Light How Semiconductors Absorb Light Advanced Scientific Computing Research (ASCR) ASCR Home About Research Facilities Science Highlights Benefits of ASCR Funding Opportunities Advanced Scientific Computing Advisory Committee (ASCAC) News & Resources Contact Information Advanced Scientific Computing Research U.S. Department of Energy SC-21/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-7486 F: (301) 903-4846 E: email@example.com More Information » March 2013 Understanding How Semiconductors Absorb Light Advances in how we calculate optical properties of semiconductors shorten the path to improved solar cells and other optoelectronic devices. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo
Method for making graded I-III-VI.sub.2 semiconductors and solar cell obtained thereby
Improved cell photovoltaic conversion efficiencies are obtained by the simultaneous elemental reactive evaporation process of Mickelsen and Chen for making semiconductors by closer control of the evaporation rates and substrate temperature during formation of the near contact, bulk, and near junction regions of a graded I-III-VI.sub.2, thin film, semiconductor, such as CuInSe.sub.2 /(Zn,Cd)S or another I-III-VI.sub.2 /II-VI heterojunction.
Devaney, Walter E. (Seattle, WA)
An iterative method for single and vertically stacked semiconductor quantum dots simulation
We present in this paper a computational effective nonlinear iterative method for calculating the electron energy spectra in single and vertically stacked InAs/GaAs semiconductor quantum dots. The physical model problem is formulated with the effective ... Keywords: Coupling effect, Electronic structure, Energy spectra, Modelling and simulation, Multishift QR method, Nonlinear eigenvalue problem, Semiconductor nanostructure, Single quantum dot, Vertically stacked quantum dot, Wave function
Yiming Li
Media Advisory: Site-wide Safety Standards | Department of Energy
Media Advisory: Site-wide Safety Standards Media Advisory: Site-wide Safety Standards Media Advisory: Site-wide Safety Standards August 1, 2012 - 12:00pm Addthis Media Contacts Michael Turner, MSA email@example.com 509-376-2872 What: Department of Energy to announce two additions to the Hanford Site-wide Safety Standards - a set of 14 areas where Hanford contractors have collaborated to establish one uniform standard to guide safe operations. The latest additions to the Site-wide Safety Standards are Fall Protection and Electrical Safety. DOE Hanford management will explain the significance of the Site-wide Safety Standards, their use and application at the Hanford Site, the benefits to workers and the example Hanford is setting for excellence in safety. Media will then be offered a demonstration of Fall Protection training, along with other training programs at the DOE's Volpentest HAMMER Training Center, operated by Mission Support Alliance.
Definition: Wide Area Monitoring, Visualization, & Control | Open Energy
Wide Area Monitoring, Visualization, & Control Wide Area Monitoring, Visualization, & Control Jump to: navigation, search Dictionary.png Wide Area Monitoring, Visualization, & Control Wide area monitoring and visualization requires time synchronized sensors, communications, and information processing that make it possible for the condition of the bulk power system to be observed and understood in real-time so that protective, preventative, or corrective action can be taken.[1] Related Terms Wide area, bes emergency, sustainability, smart grid References ↑ SmartGrid.gov 'Description of Functions' An inl LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ine Glossary Definition Retrieved from "http://en.openei.org/w/index.php?title=Definition:Wide_Area_Monitoring,_Visualization,_%26_Control&oldid=502579
Executive Order 13583, Establishing a Coordinated Government-Wide
Executive Order 13583, Establishing a Coordinated Government-Wide Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce August 18, 2011 - 11:15am Addthis Executive Order 13583 Established a "coordinated government-wide initiative to promote diversity and inclusion in the federal workforce". Wherever possible, the Federal Government must also seek to consolidate compliance efforts established through related or overlapping statutory mandates, directions from Executive Orders, and regulatory requirements. Addthis Related Articles A Government-Wide Approach to a Diverse Workforce Executive Order 13583, Establishing a Coordinated Government-Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce
Organizing and managing personal electronic files: A mechanical engineer's perspective
This article deals with the organization and management of the computer files handled by mechanical engineers on their personal computers. In engineering organizations, a wide variety of electronic files (documents) are necessary to support both business ... Keywords: Engineers, directory and file naming conventions, file sharing and file recognition and recall, information management
B. J. Hicks; A. Dong; R. Palmer; H. C. Mcalpine
Semiconductor structures having electrically insulating and conducting portions formed from an AlSb-alloy layer
A semiconductor structure. The semiconductor structure comprises a plurality of semiconductor layers formed on a substrate including at least one layer of a III-V compound semiconductor alloy comprising aluminum (Al) and antimony (Sb), with at least a part of the AlSb-alloy layer being chemically converted by an oxidation process to form superposed electrically insulating and electrically conducting portions. The electrically insulating portion formed from the AlSb-alloy layer comprises an oxide of aluminum (e.g. Al.sub.2 O.sub.3), while the electrically conducting portion comprises Sb. A lateral oxidation process allows formation of the superposed insulating and conducting portions below monocrystalline semiconductor layers for forming many different types of semiconductor structures having particular utility for optoelectronic devices such as light-emitting diodes, edge-emitting lasers, vertical-cavity surface-emitting lasers, photodetectors and optical modulators (waveguide and surface normal), and for electronic devices such as heterojunction bipolar transistors, field-effect transistors and quantum-effect devices. The invention is expected to be particularly useful for forming light-emitting devices for use in the 1.3-1.6 .mu.m wavelength range, with the AlSb-alloy layer acting to define an active region of the device and to effectively channel an electrical current therein for efficient light generation.
Spahn, Olga B. (Albuquerque, NM); Lear, Kevin L. (Albuquerque, NM)
SSRL Users' Organization Ballot
2003 SSRL Users' Organization Executive Committee (SSRLUO-EC) Ballot The SSRL Users' Organization Executive Committee represents the scientific user community to the SSRL...
Organization Leadership Organization Contact Us The Office of Economic Impact and Diversity is comprised of six offices: The Office of the Director- contact us Office of...
EA-1583: Final Site-wide Environmental Assessment | Department...
Assessment EA-1583: Final Site-wide Environmental Assessment RMOTCNaval Petroleum Reserve No. 3 (October 2008) SUMMARY: The U.S. Departmem of Energy (DOE) is...
The Primary Standards Laboratory (PSL) maintains a wide variety...
Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary thermometry standards to assure...
Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary standards to assure accurate...
Nuclear Security Administration under contract DE-AC04-94AL85000. The Primary Standards Laboratory (PSL) maintains a wide variety of primary acceleration and shock...
Flow Phenomena in an Extra Wide CSP-mold-experimental ...
Presentation Title, Flow Phenomena in an Extra Wide CSP-mold-experimental Investigations. Author(s), R�diger Bahrmann, Antje R�ckert, Herbert Pfeifer.
EA-1422: Final Site-wide Environmental Assessment | Department...
Environmental Assessment EA-1422: Final Site-wide Environmental Assessment Sandia National Laboratories Sandia National Laboratories (SNL) is one of three national...
Sandia National Laboratories Site-Wide Environmental Impact Statement...
Site-Wide Environmental Impact Statement | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency...
NNSS Final Site-Wide Environmental Impact Statement (SWEIS) ...
NNSS Final Site-Wide Environmental Impact Statement (SWEIS) | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the...
NREL: Climate Neutral Research Campuses - Campus-Wide Measures...
Campus-Wide Measures Have Greater Potential Pursuing climate neutrality on research campuses fits into the bigger picture of addressing the impacts of climate change and...
Draft Site-Wide Environmental Impact Statement Nevada | National...
> About Us > Our Operations > NNSA Office of General Counsel > National Environmental Policy Act (NEPA) > NEPA Reading Room > Draft Site-Wide Environmental Impact Statement...
World-Wide Progress Review on Superconductor Development
Oct 19, 2010 ... Recent Developments in High Temperature Superconductivity: World-Wide ... Superconductivity Efforts at the US Department of Energy (DOE):�...
Section S Summary of the Site-Wide Environmental Assessment
process that was completed in May 2002. In accordance with DOE NEPA implementing regulations, DOE is required to evaluate the Site- Wide Environmental Assessment (EA) after...
EIS-0281: Final Site-Wide Environmental Impact Statement | Department...
Final Site-Wide Environmental Impact Statement Sandia National LaboratoriesNew Mexico DOE proposes to continue operating the Sandia National LaboratoriesNew Mexico (SNL...
A hybrid bio-organic interface for neuronal photo-activation
Interfacing artificial functional materials and living neuronal tissues is at the forefront of bio-nano-technology. Attempts have been so far based onto microscale processing of metals and inorganic semiconductors as electrodes or photoactive layers in biased devices. More recently, also nanomaterials properties have been investigated. In spite of extensive research however, the communication between biological tissues and artificial sensors is still a challenge. Constraints consist in the complexity of the fabrication processes (i.e. metal and semiconductor lithography), the mechanical properties (e.g. flexibility and mechanical invasiveness) and chemical influence (e.g. inflammatory reactions). In addition, electrodes have fixed geometries that limit the location in space of the stimulus and often electrical currents are detrimental for the overall system. To this respect organic soft matter offers a chance in terms of biological affinity and mechanical properties. In particular conjugated polymers have appealing optoelectronic features which could lead to a new generation of neuronal communication and photo-manipulation techniques. So far conjugated polymers have being only tested as coatings of electrodes for neuronal activity recording. Here we report an up-scale of their use: the successful interfacing of an organic semiconductor to a network of cultured primary neurons, through optical excitation. This allows to a new paradigm for the optical stimulation of neurons which could have important implications for the development of an artificial retina based on organic photodetectors.
Maria Rosa Antognazza; Diego Ghezzi; Marco Dal Maschio; Erica Lanzarini; Fabio Benfenati; Guglielmo Lanzani
A Novel Class of High-TC Ferromagnetic Semiconductors
We have grown single crystals of novel ruthenates (Sr,Ba)(Fe,Co){sub 2+x}Ru{sub 4-x}O{sub 11} that exhibit long-range ferromagnetic order well above room temperature, accompanied by narrow-gap semiconducting properties that include a large anomalous Hall conductance, low resistivity, high carrier concentration and low coercive field, which are properties well suited to spintronic applications. X-ray diffraction, EDX, neutron diffraction and x-ray absorption measurements on single crystals firmly establish the 'R-Type' hexagonal ferrite structure (space group P6{sub 3}/mmc, No 194) and single-phase nature of all samples. The electronic structure and physical properties can be tuned by simple chemical substitution of two elements, M = Fe or Co, or by varying the relative concentration of 3d solutes and 4d Ru. Our magnetotransport, x-ray magnetic circular dichroism and magnetic moment data suggest the mechanism for FM order is quite different from that governing known dilute magnetic semiconductors.
Shlyk, L. V.; Kryukov, S. A.; De Long, L. E.; Schupp-Niewa, B.; Niewa, R.; Lynn, J. W.; Huang, Qing; Arenholz, E.; Piamonteze, C.
Optimal doping control of magnetic semiconductors via subsurfactant epitaxy
Dilute magnetic semiconductors (DMS) with high ferromagnetic ordering temperatures (T{sub c}) have vast potential for advancing spin-based electronics or 'spintronics'. To date, achieving high-T{sub c} DMS typically required doping levels of order 5%. Such high doping levels inevitably compromise the structural homogeneity and carrier mobility of the DMS. Here, we establish 'subsurfactant epitaxy' as a novel kinetic pathway for synthesizing Mn-doped germanium with T{sub c} much higher than room temperature, at dramatically reduced doping levels. This is accomplished by optimal control of the diffusion kinetics of the dopant atoms near the growth front in two separate deposition steps. The first involves a submonolayer dose of Mn on Ge(100) at low temperature, which populates subsurface interstitial sites with Mn while suppressing lateral Mn diffusion and clustering. The second step involves epitaxial growth of Ge at elevated temperature, taking advantage of the strong floating ability of the interstitial Mn dopants towards the newly defined subsurface sites at the growth front. Most remarkably, the Mn dopants trapped inside the film are uniformly distributed at substitutional sites, and the resulting film exhibits ferromagnetism above 400 K at the nominal doping level of only 0.2%.
Zeng, Changgan [ORNL; Zhang, Zhenyu [ORNL; van Benthem, Klaus [ORNL; Chisholm, Matthew F [ORNL; Weitering, Harm H [ORNL
Measuring Imputed Costs in the Semiconductor Equipment Supply Chain
We consider the order ful�llment process of a customized capital equipment supplier. Prior to receiving a �rm purchase order from the customer, the supplier receives a series of shared forecasts, which are called `soft orders'. Facing a stochastic internal manufacturing lead-time, the supplier must decide at what time to begin the ful�llment of the order. This decision requires a trade-o � between starting too early, leading to potential holding or cancellation cost, and the cost of starting too late, leading to potential loss of goodwill. We collect detailed data of shared forecasts, actual purchase orders, production lead-times, and delivery dates for a supplier-buyer dyad in the semiconductor equipment supply chain. Under the assumption that the supplier acts rationally, optimally balancing the cancellation, holding, and delay costs, we are able to estimate the corresponding cost parameters based on the observed data. Our estimation results suggest that the cost of cancellation is four times higher and the holding cost is two times higher than the delay cost. In other words, the supplier is very conservative when commencing the order ful�llment, which negates the e�ectiveness of the overall forecast sharing mechanism. 1 1
Morris A. Cohen; Teck H. Ho; Justin Z. Ren; Christian Terwiesch
Sputter deposition of semiconductor superlattices for thermoelectric applications
Theoretical dramatic improvement of the thermoelectric properties of materials by using quantum confinement in novel semiconductor nanostructures has lead to considerable interest in the thermoelectric community. Therefore, we are exploring the critical materials issues for fabrication of quantum confined structures by magnetron sputtering in the lead telluride and bismuth telluride families of materials. We have synthesized modulated structures from thermoelectric materials with bilayer periods of as little as 3.2 nm and shown that they are stable at deposition temperatures high enough to grow quality films. Issues critical to high quality film growth have been investigated such as nucleation and growth conditions and their effect on crystal orientation and growth morphology. These investigations show that nucleating the film at a temperature below the growth temperature of optimum electronic properties produces high quality films. Our work with sputter deposition, which is inherently a high rate deposition process, builds the technological base necessary to develop economical production of these advanced materials. High deposition rate is critical since, even if efficiencies comparable with CFC based refrigeration systems can be achieved, large quantities of quantum confined materials will be necessary for cost-competitive uses.
Wagner, A.V.; Foreman, R.J.; Farmer, J.C.; Barbee, T.W.
Semiconductor grade, solar silicon purification project. Final technical report
Motorola's low cost poly silicon program is described. In the process, SiF/sub 4/, a low cost by-product is reacted with mg silicon to form SiF/sub 2/ gas which is polymerized. The (SiF/sub 2/)/sub x/ polymer is heated forming volatile Si/sub x/F/sub y/ homologues which disproportionate (C.V.D.) on a silicon particle bed forming silicon and SiF/sub 4/. During the initial phases of the investigation the silicon analysis procedure relied heavily on S.S.M.S. and E.S. analysis. This analysis demonstrated that major purification had occurred and some samples were indistinguishable from semiconductor grade silicon (except possibly for phosphorus). However, more recent electrical analysis via crystal growth reveals that the product contains compensated phosphorus and boron. Work on the control or removal of the electrically active donors and acceptors could yield a product suitable for solar application. The low projected product cost and short energy payback time suggest that the economics of this process will result in a cost less than the J.P.L./D.O.E. goal of $10/Kg (1975 dollars). Finally, assuming a successful demonstration of a pilot facility, the process appears to be readily scalable to a major silicon purification facility as was proposed by Motorola and R. Katzen.
Ingle, W.M.; Rosler, R.S.; Thompson, S.W.; Chaney, R.E.
Cluster Generation Under Pulsed Laser Ablation Of Compound Semiconductors
A comparative experimental study of pulsed laser ablation in vacuum of two binary semiconductors, zinc oxide and indium phosphide, has been performed using IR- and visible laser pulses with particular attention to cluster generation. Neutral and cationic Zn{sub n}O{sub m} and In{sub n}P{sub m} particles of various stoichiometry have been produced and investigated by time-of-flight mass spectrometry. At ZnO ablation, large cationic (n>9) and all neutral clusters are mainly stoichiometric in the ablation plume. In contrast, indium phosphide clusters are strongly indium-rich with In{sub 4}P being a magic cluster. Analysis of the plume composition upon laser exposure has revealed congruent vaporization of ZnO and a disproportionate loss of phosphorus by the irradiated InP surface. Plume expansion conditions under ZnO ablation are shown to be favorable for stoichiometric cluster formation. A delayed vaporization of phosphorus under InP ablation has been observed that results in generation of off-stoichiometric clusters.
Bulgakov, Alexander V.; Evtushenko, Anton B.; Shukhov, Yuri G. [Institute of Thermophysics SB RAS, Lavrentyev Ave. 1, 630090 Novosibirsk (Russian Federation); Ozerov, Igor; Marine, Wladimir [Universite de la Mediterranee, CINaM, UPR CNRS 3118, 13288 Marseille (France)
Utility-Scale Silicon Carbide Semiconductor: Monolithic Silicon Carbide Anode Switched Thyristor for Medium Voltage Power Conversion
ADEPT Project: GeneSiC is developing an advanced silicon-carbide (SiC)-based semiconductor called an anode-switched thyristor. This low-cost, compact SiC semiconductor conducts higher levels of electrical energy with better precision than traditional silicon semiconductors. This efficiency will enable a dramatic reduction in the size, weight, and volume of the power converters and electronic devices it's used in.GeneSiC is developing its SiC-based semiconductor for utility-scale power converters. Traditional silicon semiconductors can't process the high voltages that utility-scale power distribution requires, and they must be stacked in complicated circuits that require bulky insulation and cooling hardware. GeneSiC's semiconductors are well suited for high-power applications like large-scale renewable wind and solar energy installations.
Transportation Organization and Functions
Energy.gov (U.S. Department of Energy (DOE))
Office of Packaging and Transportation list of organizations and functions, with a list of acronyms.
TREC Organization User Agreement
Organization Application to use the TREC Information- Retrieval Text Research Collections. The _____ ...
Standards Development Organization Overview
... Standards Organizations NFPA (National Fire Protection Association) ... Fire News � Annual directory � NFPA Buyer's Guide ... Headquarters ...
Organic Electronics: Organic thin-film magnetometers
Magnetometry usually requires large probes and bulky instrumentation. Organic diodes have now been used in small probes that can measure moderate magnetic fields with 10 ppm precision.
Shinar, Joseph
Stable ohmic contacts to thin films of p-type tellurium-containing II-VI semiconductors
A photovolatic device is described comprising: a light transmissive substrate; an electrically conductive, transparent layer disposed on the substrate as a first electrode; a layer of a first semiconductor disposed on the first electrode; a p-type thin film of a tellurium-containing II-VI semiconductor disposed on the first semiconductor to form a photoresponsive junction with it; and a second electrode contacting the thin film.
Szabo, L.F.; Biter, W.J.
A, A, Interconnection-Level Analysis and Planning Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning A description of the requirements for Topic A for all Interconnections under the Interconnection-Wide Transmission Planning Initiative, part of the American Recovery and Reinvestment Act. Interconnection-Wide Transmission Planning Initiative: Topic A, Interconnection-Level Analysis and Planning More Documents & Publications Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Eastern Interconnection on Electric Resource Planning and Priorities Microsoft Word - yDE-FOA-0000068.rtf Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Western Interconnection on Electric Resource Planning
Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation
Interconnection-Wide Transmission Planning Initiative: Topic B, Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Eastern Interconnection on Electric Resource Planning and Priorities Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation Among States in the Eastern Interconnection on Electric Resource Planning and Priorities A description of the requirements for Topic B for the Eastern Interconnection under the Interconnection-Wide Transmission Planning Initiative, part of the American Recovery and Reinvestment Act. The fundamental purpose of the awards under Topic B is to facilitate dialogue and collaboration among the states in the respective interconnections (or among state agencies, in the Texas Interconnection). Interconnection-Wide Transmission Planning Initiative: Topic B, Cooperation
Genome-wide discovery of missing genes in biological pathways of prokaryotes
Genome-wide Genome-wide discovery of missing genes in biological pathways of prokaryotes Yong Chen 1,3,4,5 , Fenglou Mao 1,2 , Guojun Li 1,3 , Ying Xu 1,2,6* From The Ninth Asia Pacific Bioinformatics Conference (APBC 2011) Incheon, Korea. 11-14 January 2011 Abstract Background: Reconstruction of biological pathways is typically done through mapping well-characterized pathways of model organisms to a target genome, through orthologous gene mapping. A limitation of such pathway-mapping approaches is that the mapped pathway models are constrained by the composition of the template pathways, e.g., some genes in a target pathway may not have corresponding genes in the template pathways, the so-called "missing gene" problem. Methods: We present a novel pathway-expansion method for identifying additional genes that are possibly involved in a target pathway after pathway mapping,
2 www.trnmag.com Technology Research News February 23/March 2, 2005 Process yields semiconductor foam
Wayne State University have made crystalline aerogels -- new semiconductor materials that are very porous, giving them very high surface areas. Unlike conventional aerogels, the researchers' materials
Ruina, Andy L.
Printing Highly-aligned Single-crystalline Organic Electronic Thin Films |
Printing Highly-aligned Single-crystalline Organic Electronic Thin Films Printing Highly-aligned Single-crystalline Organic Electronic Thin Films Monday, September 23, 2013 Organic semiconductor materials have some intriguing advantages compared to their inorganic counterparts: low-cost and versatile manufacturing (e.g. roll-to-roll printing), material abundance and new form factors (e.g. flexible, transparent and stretchable). However, solution-processed organic devices are usually made and optimized with poorly scalable fabrication using lab-based techniques such as spin coating or dip coating. A better route for organic-electronics fabrication is printing, which can potentially realize large-area, high-throughput, low-cost fabrication on an industrial scale. Fluence image FLUENCE: fluid-enhanced crystal engineering. Solution shearing (a) using a
Charge and Spin Transport in Dilute Magnetic Semiconductors
This proposal to the DOE outlines a three-year plan of research in theoretical and computational condensed-matter physics, with the aim of developing a microscopic theory for charge and spin dynamics in disordered materials with magnetic impurities. Important representatives of this class of materials are the dilute magnetic semiconductors (DMS), which have attracted great attention as a promising basis for spintronics devices. There is an intense experimental effort underway to study the transport properties of ferromagnetic DMS such as (Ga,Mn)As, and a number of interesting features have emerged: negative magnetoresistance, anomalous Hall effect, non-Drude dynamical conductivity, and resistivity maxima at the Curie temperature. Available theories have been able to account for some of these features, but at present we are still far away from a systematic microscopic understanding of transport in DMS. We propose to address this challenge by developing a theory of charge and spin dynamics based on a combination of the memory-function formalism and time-dependent density functional theory. This approach will be capable of dealing with two important issues: (a) the strong degree of correlated disorder in DMS, close to the localization transition (which invalidates the usual relaxation-time approximation to the Boltzmann equation), (b) the essentially unknown role of dynamical many-body effects such as spin Coulomb drag. We will calculate static and dynamical conductivities in DMS as functions of magnetic order and carrier density, which will advance our understanding of recent transport and infrared absorption measurements. Furthermore, we will study collective plasmon excitations in DMS (3D, 2D and quantum wells), whose linewidths could constitute a new experimental probe of the correlation of disorder, many-body effects and charge and spin dynamics in these materials.
Ullrich, Carsten A.
Production of films and powders for semiconductor device applications
A process is described for chemical bath deposition of selenide and sulfide salts as films and powders employable as precursors for the fabrication of solar cell devices. The films and powders include (1) Cu{sub x}Se{sub n}, wherein x=1--2 and n=1--3; (2) Cu{sub x}Ga{sub y}Se{sub n}, wherein x=1--2, y=0--1 and n=1--3; (3) Cu{sub x}In{sub y}Se{sub n}, wherein x=1--2.27, y=0.72--2 and n=1--3; (4) Cu{sub x}(InGa){sub y}Se{sub n}, wherein x=1--2.17, y=0.96--2 and n=1--3; (5) In{sub y}Se{sub n}, wherein y=1--2.3 and n=1--3; (6) Cu{sub x}S{sub n}, wherein x=1--2 and n=1--3; and (7) Cu{sub x}(InGa){sub y}(SeS){sub n}, wherein x=1--2, y=0.07--2 and n=0.663--3. A reaction vessel containing therein a substrate upon which will form one or more layers of semiconductor material is provided, and relevant solution mixtures are introduced in a sufficient quantity for a sufficient time and under favorable conditions into the vessel to react with each other to produce the resultant salt being prepared and deposited as one or more layers on the substrate and as a powder on the floor of the vessel. Hydrazine is present during all reaction processes producing non-gallium containing products and optionally present during reaction processes producing gallium-containing products to function as a strong reducing agent and thereby enhance reaction processes. 4 figs.
Bhattacharya, R.N.; Noufi, R.; Li Wang