A method is provided for transmitting radio signals. Two channels are defined by two transmit antennas, having two orthogonal directions, together with two receive antennas, having two orthogonal directions. An optimal quality of one received signal is determined by signal processing, which emulates a rotation of the two orthogonal receive directions, and a mutual interference of the signals received on the two channels, due to a polarization mismatch, is cancelled, based on a corresponding optimal rotation angle.

Multiple antenna (MIMO) technologies have become commonplace in wireless communications systems in order to provide spatial diversity and improve performance and/or provide spatial multiplexing and increase the transmitted data rate. For instance, mobile WiMAX systems employ two MIMO profiles on the downlink:
Matrix A: This is the well-known Alamouti space-time code (STC) for transmit diversity described in S. M. Alamouti, "A Simple Transmit Diversity Technique for Wireless Communications," IEEE Journal on Selected Areas in Communications, vol. 16, no. 8, pp. 1451-1458, October 1998. This MIMO scheme provides diversity, but it has no spatial multiplexing gain. Although 2 transmit antennas are used, the transmitted data rate is the same as in single antenna systems. The virtue of this technique is that it provides a transmit diversity order of 2. With N antennas at the receiver, the total diversity order is 2N. Therefore, with 2 receive antennas, it leads to 4th-order diversity.
Matrix B: This scheme is based on spatial multiplexing (SM) of two data streams transmitted by the two transmit antennas. SM does not provide any diversity on the transmitter side, but, with N antennas at the receiver and maximum-likelihood detection (MLD), it provides a diversity order of N. In other words, second-order diversity can be achieved with 2 receive antennas.
There are also more advanced 2×2 MIMO schemes providing better diversity/multiplexing tradeoffs. These include the Golden code, in J.-C. Belfiore, G. Rekaya, and E. Viterbo, "The Golden Code: A 2×2 Full-Rate Space—Time Code with Nonvanishing Determinants," IEEE Transactions on Information Theory, Vol. 51, No. 4, pp. 1432-1436, April 2005, which is the best known STC of dimension 2×2, or the recently proposed STC, in the European Patent Application, EP 07 290 394.1, which provides similar performance to the Golden code while simplifying the optimum detector by orders of magnitude. The STC in said patent application is described by the coding matrix:
                              D          =                      [                                                                                as                      1                                        +                                          bs                      3                                                                                -                                              cs                        2                        *                                                              -                                          ds                      4                      *                                                                                as                      2                                        +                                          bs                      4                                                                                cs                      1                      *                                        +                                          ds                      3                      *                                                                                ]                          ,                            (        1        )            where a, b, c, and d are complex-valued design parameters and the star designates complex conjugate.
In this matrix representation, the first column represents the symbol combinations transmitted during a first symbol interval and the second column represents the symbol combinations transmitted during the second symbol interval. The first row of the matrix gives the symbol combinations transmitted from the first transmit antenna, and the second row of the matrix gives the symbol combinations transmitted from the second antenna. As described in said patent application, the complexity of the maximum likelihood (ML) decoder of this code is proportional to M2, where M is the size of the signal constellation.
To further increase the spatial multiplexing and the diversity gains, future standards will include MIMO systems with a larger number of antennas, for instance 4×4 MIMO schemes. There are many well-known STC designs for this type of systems. The simplest one is the pure spatial multiplexing scheme, which consists of transmitting in parallel 4 data streams using the 4 transmit antennas. Another one is the Double Alamouti scheme, which consists of transmitting one Alamouti matrix from the first two antennas and another Alamouti matrix in parallel from the other two antennas. This scheme offers a multiplexing gain of 2 (compared to 4 in the SM case), but its diversity order is 8 instead of 4 in the SM technique. More generally, one can design an STC providing a multiplexing gain of 4 and leading to high diversity and coding gains, but the complexity of the optimum decoder would be excessive for practical applications.                When the size of a MIMO system is increased, for instance by a factor 2 for upgrading a K×K MIMO system into a 2K×2K MIMO system, the complexity, or the computation load, is increased by a large factor. Consequently, more costly technologies need to be used. Furthermore, these technologies imply higher power consumption, thus causing an increased need for cooling the integrated circuits. The total cost is thus quite impacted.

Wireless communications method and system with spatial multiplexing using dually polarized antennas and corresponding receiver


A dual mode ceramic filter has an enclosure with two cavities separated by a wall, and two TM dual-mode resonators, each TM dual-mode resonator positioned in a corresponding cavity. Each TM dual-mode resonator has first and second modes, and a body having a central portion with a plurality of arms extending outwardly from the central portion. The filter also has two input conductive members, each input conductive members positioned in a corresponding cavity. Each input conductive member is disposed proximate a corresponding TM dual-mode resonator for coupling between the input conductive member and the TM dual-mode resonator.

A wireless telecommunication system typically includes a plurality of base stations connected to a communication network. Each base station includes radio transceivers associated with a transmission tower. A typical base station includes one or more filters for processing IF signals. One such filter is known as a microwave cavity filter which includes resonators formed in cavities in order to provide a desired frequency response when signals are input to the filter.
One type of cavity filter design employs dual-mode resonators utilized in the cavity filters, providing desired filter functions while reducing the filter size compared to conventional cavity filters utilizing single mode resonators. However, many existing dual-mode resonators are difficult to manufacture due to the shape of the resonator structure. Other existing resonators that use hybrid modes, are too large and bulky for certain applications.
Accordingly, an objective of the present invention is to provide a structure for smaller base station cavity filters which avoids the above-noted problems.


A fuel pump has a motor mounted within a housing with a shaft extending therefrom to which a helically shaped impeller is fitted for pumping fuel from a fuel tank to an automotive engine. An end section of the housing has an inlet leading from the fuel tank to a pre-swirl fuel channel or trough located at the radially outermost perimeter of an impeller mating face on the end section. The trough has an inlet ramp which routes fuel to an inclined section with an axial grade to force the fuel to flow in the direction of impeller rotation. A trough termination ramp between the inclined section and the inlet ramps fuel toward the impeller at a steeper grade than the inclined section such that the fuel trough becomes flush with the impeller mating face. Fuel can thus be picked-up by the impeller throughout at least 340.degree. of rotation.

Electric fuel pump designs have evolved to a steady design state of employing gerotors, roller vanes, or modified fluid turbine principles for generating high fuel pressure in essentially all current vehicle applications. Fuel is picked-up by such fuel pumps over an arc extending between 60.degree. and 120.degree. around a pumping channel formed along the pumping element circumference. Low pressure and high pressure regions are thus created at the fuel inlet and fuel outlet, respectively, which are at opposite ends of the channel. Since the pumping channel terminates abruptly at the outlet, a pulsing effect is created as the pumping element rotates past the non-channel circumferential portion of the pump housing. These hydraulic pulsations result in decreased pump efficiency since high energy fuel either is carried from the high pressure side to the low pressure side or leaks across. In addition, prior fuel pump inlets have a sudden pressure decrease in the vacuum stage leading to the pumping channel inlet thus creating turbulence and enhancing the conditions which promote undesirable cavitation. These prior inlets also had a secondary backflow which reduced pump efficiency.
Other pumps, such as that disclosed in U.S. Pat. No. 4,880,352 (Aarestad), have side inlets, as opposed to the end inlet of the present invention, which do not ramp fuel into the impeller inlet channel. In addition, the pump shown in the Aarestad patent picks up fuel through only 180.degree. as opposed to at least 340.degree. for the present invention.


An apparatus for forming an image on the nail of a user comprises a handle body having an outer gripping surface and an inner surface defining a clear bore extending completely therethrough and an image transfer body formed of a transparent pliable material having an outer surface corresponding to the clear bore of the handle body and an image transfer surface extending from the handle body. A kit may include the apparatus and a plate containing at least one image location having a depression adapted to contain a portion of paint to be transferred to a user's nail. A user locates a portion of paint in depression of the plate, presses an image transfer surface on the image transfer body on the portion of paint to transfer the portion of paint to the image transfer surface and applies the image transfer surface to a nail of the user.

1. Field of Invention
The present invention relates generally to personal decorating and in particular relates to a method and apparatus for forming an image on the nail of a user.
2. Description of Related Art
In personal fashion, many users enjoy applying colors and images to their nails for decorative effect. In particular, the application of images to the nails of a user provides a pleasing visual appearance. Conventionally, such images may be applied to the user's nail through painting freehand however it will be appreciated that such images require great skill to apply and have limited detail and consistency which may be applied. Additionally, images may be formed on the nail by applying a sticker or the like having the desired image. Disadvantageously, such stickers will form a raised image on the nail resulting in a uneven finish and are also limited to the images and colors published and available for purchase.
To address these deficiencies, the use of image stampers has been adopted whereby an image is formed on a plate using paint of a desired color. Thereafter a rubber stamp is utilized to pick up and transfer the image from the plate to the nail. A disadvantage of conventional stampers is that they block the image which the user is attempting to pick up thereby making precise placement of the image difficult. This is especially difficult in circumstances where a user wishes to form an image of multiple colors. In these circumstances, a user would commonly form each part of the image which is to be formed from a particular color as a separate image part. The stamper would then be used to transfer each image part to a common composite image on a transfer plate or the like. This allows the user to verify alignment of the image parts before transfer to the user's nail or start over if the image parts do not sufficiently align. It will be appreciated that such process may be time consuming and difficult to complete for detailed images having many colors.

Method and apparatus for forming an image


A device connector (10) includes a service cover (30) to close a service hole (22) on a case (20). A case-side connector (60) is arranged in the case (20) and mounted in a mounting recess (42) in a terminal block (40). A cover-side connector (50) is provided integrally to the service cover (30) and is connected to the case-side connector (60) in a waiting state to form an interlock circuit when the service cover (30) is mounted on the case (20). Flexible pieces (65) hold the case-side connector (60) with a clearance (CL) between the case-side connector (60) and the inner wall of the mounting recess (42) when the case-side connector (60 is in the waiting state. On the other hand, the flexible pieces (65) bias the case-side connector (60) to return the case-side connector (60) to the waiting state when the clearance (CL) changes.

1. Field of the Invention
The invention relates to a device connector in a case of a device in a vehicle, the case being formed with an opening used to perform a bolt tightening operation for a terminal block in the case.
2. Description of the Related Art
U.S. Patent Application Publication No. 2010/0255728 discloses a device connector in a case of a device. A tightening tool is inserted through an opening in the case through to tighten bolts so that terminals of busbars or the like can be connected electrically conductively. A service cover is mounted on the case to close the opening after the bolt tightening operation is completed so that water, dust and the like do not enter the case through the opening.
An interlock circuit switches an electrical circuit in the device to an OFF state as a safety measure when the service cover is removed from the case even though the terminals are in an electrically conductive state. Specifically, the interlock circuit is formed and the electrical circuit is switched to an ON state by connecting a cover-side connector on the service cover and a case-side connector in the case. On the other hand, the interlock circuit is cut off and the electrical circuit is switched to the OFF state when the service cover is removed from the case.
Several tightening portions may be arranged on one terminal block in the above-described device connector. Openings could be provided in one-to-one correspondence with the tightening portions. However, a separate service cover then would be required for each opening, thereby making a mounting operation cumbersome. A common opening could be provided for several tightening portions and one service cover could be provided for covering the opening. However, the larger service cover is more likely to be misaligned during mounting on the case. The interlock circuit may not be formed if the connectors on the cover and the case are not aligned properly.
The present invention was completed based on the above situation and an object thereof is to connect a cover-side connector and a case-side connector precisely by absorbing a misalignment in mounting a service cover on a case.


A camera has a lens system that includes a lens barrel incorporating therein an image taking lens, the lens barrel being variable in a barrel length between a collapsed state in which the barrel length is relative short and a photographic state in which the barrel length is relative long. The lens barrel comprises a light quantity control member that controls quantity of photographic light passing through the image taking lens, and a light quantity control member saving and advancing mechanism that provides such a control that when the lens barrel changes over from the photographic state to the collapsed state, the light quantity control member is saved from a photographic optical axis, and when the lens barrel changes over from the collapsed state to the photographic state, the light quantity control member is advanced to the photographic optical axis.

1. Field of the Invention
The present invention relates to a camera in which subject light is formed on a solid state imaging device so that an image signal is created.
2. Description of the Related Art
Hitherto, such a type of camera that photography is performed on a silver halide film comes into wide use. And recently, in addition to such a type of camera, there rapidly comes into wide use a digital camera in which a subject is image-formed on a solid state imaging device such as a CCD imaging device or a CMOS imaging device to create an image signal.
Also in such a digital camera, there is strongly needed an improvement of a portability as well as an improvement of a photographic efficiency. There is known such a type of digital camera that in order that a desired view angle of photography is available through varying a focal length and the camera is convenient to carry about, at the time of non-photography a lens barrel, which incorporates thereinto an image taking lens constituted of a plurality of lens groups, is collapsed into a cover member of the camera so that the respective lengths among the plurality of lens groups constituting the image taking lens are under lengths of the minimum requirements for photography, and at the time of photography the lens barrel is extended from the cover member of the camera so that the respective lengths among the plurality of lens groups are lengths necessary for photography (cf. Japanese Patent Application Laid Open Gazette TokuKai Hei. 5-34769).
Hitherto, in a digital camera having the above-mentioned lens barrel, it is attempted to provide thinness of the lens structure by collapsing an image taking lens so as to narrow intervals between ones arranged on an optical axis, for example, lens groups, light quantity control members such as a shutter and an aperture, and a solid state imaging device, as far as possible.
However, there is a limit as to providing thinness through narrowing intervals between ones arranged on an optical axis as far as possible.


A measurement system includes a broadband light source that outputs a broadband light, an optical splitter that divides the broadband light into a plurality of divided light beams and a plurality of optical sensors, each optical sensor configured to receive a single one of the divided light beams and measure an electrical parameter of a conductor.

The field of the present disclosure relates generally to fiber optic current transducers based on the Faraday effect. More particularly, the present disclosure relates to distributed, multiplexed fiber optical current transducers using optical power division.
Fiber optic current transducers (FOCT) measure current based on the Faraday effect. The Faraday effect is a magneto-optical phenomenon (i.e., the interaction of light with a medium in a magnetic field). The interaction of light with the medium in a magnetic field causes a rotation of the plane of polarization of the light by an angle that is linearly proportional to the component of the magnetic field in the direction of propagation of the light.
Typically, FOCT systems support only a single flint glass fiber and are capable of measuring only single phase electrical current. In order to measure multiple phases of electrical current, multiple FOCT systems are required. The use of multiple FOCT systems to measure current increases cost and reduces efficiency.

Distributed, multiplexed fiber optic current transducer using optical power division


A process control system which includes at least one manipulated variable and at least one controlled variable, provides a method for robust control of a process. Predetermined constraints of the manipulated variables and the controlled variables, and the present values of the manipulated variables are obtained. New values are calculated for the controlled variables for a predetermined number of points in the future, such that the values of the controlled variables are within the predetermined range thereby obtaining an optimal robustness of the resultant controller. The manipulated variables are also calculated to be within predetermined constraints, and the controlled variables to fall within a predetermined range when controllable. From a plurality of solutions, a most robust solution is selected. Then the manipulated variables are adjusted to cause the process control system to drive the values of the controlled variables to the calculated values.

The present invention relates to control systems, and more particularly, to a method of robust multivariable predictive control (RMPC) techniques utilizing range controls.
In present day process control systems, many techniques are presently in use which utilize model predictive control techniques which control process variables to predetermined setpoints. Oftentimes the setpoints are a best estimate by the system operator of the value of the setpoint or set points. When a process is being controlled to a setpoint, the controller may not be able to achieve the best control performances, especially under process/model mismatch.
In order to enhance the controller performance, there is a need to provide a method for controlling a process which controls the process variables (i.e., controlled variables) by commanding each manipulated variable associated with the controller of the process control system to a corresponding range, i.e., each control specification having an upper bound and a lower bound, The result is that the Frobenius norm of the controller is minimized and thus the process is controlled within the desired tolerance of the product specification, the impact to the system is reduced, and results in a more robust controller.

Method of multivariable predictive control utilizing range control


Methods, computer-readable media, software, systems and apparatuses may retrieve, via a computing device and over a network, information related to one or more characteristics of a particular application or service deployed in a computing environment. The particular application or service may be associated with a class of applications or services based on the information. A type of personal data collected may be determined for each application or service in the associated class. For the particular application or service, a risk metric indicative of a type of personal data collected by the particular application or service in relation to the type of personal data collected by other applications or services in the associated class may be determined. An additional application or service with a lower risk than the particular application or service may be recommended.

Applications and services may collect data, which in some cases may be sensitive information. In some instances, data collection may be utilized to provide certain features and/or functionalities to users. However, in other instances, data may be collected solely to facilitate targeted advertising and other marketing strategies. Furthermore, such collected data may be sold or otherwise provided to other companies. In some instances, there may be a risk of loss of data due to security vulnerabilities in a system.
Application developers and service providers may generally disclose a type, nature, and/or amount of data collected by the software or service. However, end users may not be attentive to such disclosures. Furthermore, users may not understand the risks, and may sometimes forget what data is being collected, due to a large number of applications and services they may be using. Also, in some instances, users may not understand the full scope of any benefit provided by such data collection. Also, for example, parents may not fully understand an extent and/or type of data that may be collected by applications or services being used by their children.
Accordingly, there may be an advantage to automatically analyze disclosures provided by application developers and service providers to determine risk profiles associated with applications and services. In some instances, it may be of significance to compare risk profiles for different applications or services that may provide similar functionalities. In some aspects, it may be advantageous to automatically identify and recommend applications and/or services that may carry a lower risk of unnecessary data collection.

Dynamic system profiling based on data extraction


Methods of generating and expanding proliferative, multipotent connective tissue progenitor cells from embryonic stem cells and embryoid bodies are provided. Also provided are methods of generating functional tendon grafts in vitro and bone, cartilage and connective tissues in vivo using the isolated cell preparation of connective tissue progenitor cells.

The present invention relates to methods of generating and isolating proliferative, non terminally differentiated connective tissue progenitor cells from embryonic stem cells and embryoid bodies and, more particularly, to methods of using such cells for cell based therapy and tissue engineering applications.
Cell-based tissue engineering is an evolving interdisciplinary area that offers new opportunities for clinical applications, creating a tool for repairing and replacing damaged or lost tissues with biological substitutes. The shortage of organ transplants and the exceeding number of patients on waiting lists greatly encourage the development of this field. The fundamentals of tissue engineering combine cells, bioactive matrices and chemically and biophysically defined in-vitro culture conditions. For tissue engineering, cells must be easily isolated, sufficient in numbers, with a great proliferation capacity and a well-defined differentiation potential. A number of cell sources have been suggested including primary cells and stem cells which are either host- or donor-derived. A wide array of matrices, either biologically or synthetically designed, are to provide the mechanical cues and three-dimensional environment, supporting cell attachment, migration, proliferation, differentiation and organization into complex tissues. Controlling stem cell proliferation and differentiation into any desired cell type requires the identification of chemicals (e.g., hormones and growth factors) and/or growth conditions (e.g., static or dynamic culturing conditions), which regulate the differentiation into the desired cell or tissue.
Connective tissue repair and regeneration are subjected to intensive research within clinical medicine. Damaged or disordered connective tissues, such as bone, cartilage and tendons need to be reconstructed or replaced due to traumatic injuries, degenerative diseases, tumor resections and congenital malformations. Current strategies in reconstructive orthopedic surgery include the use of autografts, allografts and artificial substitutes, all subjected to various limitations. While the use of cell grafts is limited by availability and morbidity, synthetic grafts are osteoconductively inferior to their biological counterparts, and could fail.
Mesenchymal stem cells (MSCs) have previously been derived from bone (Sottile, V et al 2002), bone marrow (Pittenger, M. F et al, 1999), muscle (Mastrogiacomo, M et al 2005), and fat (Zuk, P. A et al, 2001), and were capable of differentiating into adipocytic, chondrocytic, osteocytic or myogenic lineages.
Human embryonic stem cells (hESCs) hold great promise as a source of cells for tissue engineering. Their ability for practically unlimited self-renewal can potentially provide the required amount of cells needed for ex vivo tissue construction. In addition, they are characterized by a developmental potential to differentiate into any cell type of the mammalian embryo, and recently have been efficiently derived by means of somatic cell nuclear transfer, creating patient-specific immune-matched cell lines. hESCs have been shown to be able to form vascularized tissue-like structures when grown on either PLGA/PLLA or alginate porous scaffolds.
Several approaches have been recently described for isolating MSC-like cells from hESCs.
For example, Olivier E N., et al., 2006 [Olivier, E. N., et al., 2006, Stem Cells 24, 1914-1922] cultured spontaneously differentiating cells of hESCs colonies which were scraped from the edges of the colonies ("raclures") until a thick multi-layer epithelium was formed (at least 4 weeks). The cells of the thick epithelium were further dissociated and routinely passaged. The resulting cells exhibited surface phenotype of MSCs such as CD105+/CD166+/HLA-ABC+/CD73+/CD45−/HLA-DR− and were capable of in-vitro differentiation into osteoblasts and adipocytes. However, the use of such a method (the "raclure method") is limited because specific ESCs are mechanically scraped from ESC colonies cultured on mouse feeder cells, which may result in a crude, non-defined, population of cells.
In another study Barberi, T., et al. (2005) co-cultured hESCs on mouse OP-9 stromal feeder layers and following 40 days of co-culture isolated CD73-positive cells (MSC-like cells) and replated them in the absence of the stromal cells. However, this method is limited by the extremely low yield of the MSC-like cells (only 5% of the cells were CD73-positive cells) and by the co-culturing of the hESCs on mouse feeder-layers, which complicates culturing procedures and limits the use for cell-based therapy.
Other approaches utilized ESCs which have undergone spontaneous differentiation to embryoid bodies (EBs) in order to generate in-vitro committed cells of the osteogenic lineage.
For example, EBs were dissociated into single cells and were further induced to terminally differentiate into the osteogenic lineage by culturing them in an osteogenic medium without passaging for 21 (Sottile V, et al., 2003) or 28 (Bielby et al., 2004) days. The resulting cells expressed osteogenic markers and formed mineralized nodules.
Other studies obtained committed cells of the osteogenic lineage by plating intact EBs on adherent culture plates and culturing the EBs for at least 22 days without passaging (Cao T., et al. 2005). Thus, Cao et al. (2005), Bielby et al. (2004) and Sottile et al. (2003) concluded that culturing cells of EBs in an osteogenic medium results in terminally differentiated cells of the osteoblast cell lineage.
There is thus a widely recognized need for, and it would be highly advantageous to have, hESC-derived multipotent cells for tissue engineering devoid of the above limitations.

Human embryonic stem cell-derived connective tissue progenitors for tissue engineering

Technion Research & Development Foundation Ltd.


A mold tool for forming an electronic component having a semiconductor chip sealed on a supporting member by a resin-molded package, includes an upper mold having an upper cavity and a lower mold having a lower cavity, the package being molded in the cavities. Upper and lower gates are arranged at opposing surfaces of the molds and symmetrically formed with respect to a parting face of the mold tool to connect with the cavities. A method for forming the component includes the steps of inserting the supporting member with the chip in the cavities of the molds of the mold tool, clamping the molds, injecting molten resin into the cavities of the clamped molds through the upper and lower gates, cooling the molten resin in the cavities, and separating the molds from each other and removing the component from the cavities. The supporting member has a recess where the chip is located, and the recess has such a depth that a distance between an upper surface of the chip located in the recess and an upper surface of the package is substantially equal to a distance between a lower surface of a portion where the recess is formed and a lower surface of the package. A lead frame is one of the supporting member and includes a cutout formed at a portion corresponding to the gates, which are connected to each other through the cutout.

The present invention relates to a mold tool for forming an electronic component having a semiconductor chip sealed on a substrate by resin, a method for forming the electronic component, and a lead frame on which a semiconductor chip can be put and thereafter the chip on the frame is sealed by resin.
Referring to FIGS. 6-8, a known semiconductor sealing method will be described hereinafter. FIG. 6 is a schematic cross-sectional view of a known resin-molded electronic component 21 and FIGS. 7 and 8 show example phenomena caused by molding in the known semiconductor sealing method.
In FIG. 6, a substrate 23 for attaching a semiconductor 22 is flat. The chip 22 is sealed on the substrate 23 by resin, resulting in a difference between the distance (c) from the upper surface of the chip 22 to the upper surface of a sealing portion 27 and the distance (d) from the lower surface of the substrate 23 to the lower surface of the sealing portion 27.
However, since the configuration elements such as the sectional area and the thickness of the molded product have a great effect on the flow of the molten resin, the above construction causes the resin to firstly flow in the lower mold having a cavity with a larger depth than the depth of the upper mold as shown in FIG. 7 and then flow to the upper mold after the lower cavity of the lower mold is filled with resin. As a result thereof, the resin flow forces gas in the cavities to be held in the upper mold having the cavity with the smaller depth, forming voids in the upper cavity, thus causing disadvantages such as poor insulation properties of the product. As shown in FIG. 8, if the substrate 23 is easily deformed, the substrate 23 is easily deformed by the resin flow. The forward ends 28a and 28b of the two resin flows entering the upper and lower cavities after passing through a gate 24 are difficult to coincide with each other. Therefore, after the lower cavity is filled with the resin, the pressure caused in the lower cavity by the resin is applied to the substrate 23 to deform, resulting in a poor quality of the electronic component molded by resin.

Matsushita Electric Industrial Co., Ltd.


A semiconductor integrated circuit includes: a data output terminal; a first semiconductor element connected between a first operating potential point and the data output terminal; a second semiconductor element connected between the data output terminal and a second operating potential point; first control means connected to a control input terminal of the first semiconductor element; second control means connected to a control input terminal of the second semiconductor element; first generating means for generating a first predetermined voltage; and second generating means for generating a second predetermined voltage higher than the first predetermined voltage. When voltage at the data output terminal is higher than the second predetermined voltage, the first control means controls the first semiconductor element to be in the OFF-state, and the second control means controls the second semiconductor element to be in the ON-state to lower the voltage of the data output terminal to the second predetermined voltage. On the other hand, in the case where the voltage of the data output terminal is lower than that of the first predetermined voltage, the output of the first control means controls the first semiconductor element so that it is in the ON-state and the output of the second control means controls the second semiconductor element so that it is in the OFF-state so as to raise the voltage of the data output terminal to the first predetermined voltage.

This invention relates to a semiconductor integrated circuit, and in particular to a semiconductor integrated circuit provided with an output buffer circuit for sending signals within the semiconductor circuit to the exterior of the integrated circuit with a relatively high current drive ability.
Such a prior art device is disclosed in the National Convention Record, 1987, The Institute of Electronics, Information and Communication Engineers: Part 2, p. 2-218 (in Japanese). This prior art example has a function to preset the potential of the output terminal at a certain medium level.

High speed MOSFET output buffer with low noise


An unloading plunger having a chamber for compressed gas and a method for unloading liquid from a wellbore via ascending of the unloading plunger including ascending via formation pressure the unloading plunger from the bottom portion of the wellbore to a rest position at a wellhead and releasing compressed gas from the chamber into the wellbore during the ascending to decrease hydrostatic pressure of liquid in the wellbore above the unloading plunger.

A well may be unloaded by removing a column of kill fluid from the wellbore to initiate flow from the subterranean formation (reservoir). Practices for unloading a well may include circulation of lower density fluid, nitrogen lifting, swabbing, plunger lift, and so on. The selection of the technique employed may depend on the well completion design, reservoir characteristics, and other factors. Plunger lift is an artificial lift technique for unloading a well that utilizes well energy of formation pressure to cycle a plunger (e.g., traveling piston) up the tubing or casing of a well. The plunger may serve as a solid interface between the liquid above the plunger and the fluid (e.g., primarily gas) below the plunger. The fluid below the plunger may supply the energy (via formation pressure) to propel the plunger (and the liquid slug above the plunger) to the Earth surface. Once the plunger is at the surface, the well may produce hydrocarbon from the subterranean formation. Then, when a column of liquid again accumulates in the wellbore, the well (wellbore) may be shut in to facilitate (allow) the plunger to drop back to bottom. Another cycle may begin once the well has built up sufficient pressure. Cycle frequency may vary with each well and type of production.
Plunger lift is an artificial-lift alternative applied to gas and oil wells typically having high gas-liquid ratio (GLR). Plunger lift may be an artificial-lift technique principally utilized in gas wells to unload liquid (e.g., condensate, water, etc.). However, plunger lift is also applied to oil wells with high GLR and oil wells without high GLR. Again, plunger lift is a type of gas-lift method that employs a plunger that goes up and down inside the tubing. The plunger provides an interface between the liquid phase above the plunger and the lift gas below the plunger to reduce liquid fallback.


A method and a dual-source CT are disclosed. In at least one embodiment, the projection data of the integrating and of the counting detector from a quarter rotation of the gantry is used jointly for reconstruction of a first tomographic image dataset, the energy-resolved projection data of the counting detector from at least one half rotation of the gantry being used for reconstruction of at least a second material-selective tomographic image dataset, and at least one tomographic result image dataset being formed by overlaying the first tomographic image dataset with the material selection of the second image dataset.

Dual-source CT systems with a conventional integrating scintillation detector and a counting detector are known. In such cases both measurement systems are operated simultaneously to scan a measurement object, mostly a patient. Such a dual-source CT system contains two emitter-detector systems including an x-ray emitter and the respectively associated detector in each case, which are disposed offset at an angle to each other on a gantry.

Method and computed tomography system for generating tomographic image datasets with integrating detector and counting detector


An improved retainer, apparatus and method for retaining a circuit card are provided, through the use of a circuit card retainer comprising a length of spring wire defining a longitudinal axis of the retainer, lying in a plane of the retainer, and formed to define a wavy section of the retainer having peaks and valleys of the spring wire lying in the plane of the retainer with at least some of the peaks and/or the valleys being offset from the axis of the retainer. Some embodiments include a retainer guide, having a groove therein for properly orienting the wavy section of the retainer with respect to the circuit card.

Electronic equipment often employs printed circuit boards or cards. These cards typically are mounted in a chassis or card rack by stacking the cards in row alignment with one another. Row alignment in the chassis is defined by slotted or spaced surfaces within or on the chassis, with each card placed in a slot or between a pair of spaced surfaces.
Many applications for such retainers require that the retainer secure a printed circuit card to the chassis under severe shock and vibration conditions. This is particularly true for retainers used to secure circuit cards in equipment for spacecraft, or military aircraft.
In addition, the printed circuit board chassis often does not allow sufficient cooling air or fluid to pass over the circuit board, particularly where the chassis must be sealed from the surrounding environment, or where the chassis is densely packed with circuit components. To provide adequate cooling for components on the circuit card, heat generated on the circuit card is conducted to an edge of the circuit card, through a metal heat sink, inner copper planes, or a heat pipe attached to the circuit card, and then transferred by thermal conduction through the chassis to a heat exchanger or plenum operatively attached to the chassis. In order to achieve the required heat transfer, the edge of the circuit card must be clamped securely by the retainer against a clamping surface, of the chassis or heat sink, with enough force, directed normal to the card, to ensure intimate contact of the edge of the card with the clamping surface of the chassis or heatsink.
In one prior approach to retaining circuit cards, the edge of the card is positioned within a channel between a pair of oppositely facing surfaces. A screw-actuated wedge locking device installed in the channel between one of the surfaces and the card is utilized for forcing the edge of the card into contact with the other surface, to secure the card against movement and to clamp the edge of the card against the clamping surface to facilitate heat transfer from the edge of the card into the clamping surface. Such wedge locking type retainers are sometimes attached to the edge of the circuit card. U.S. Pat. No. 4,823,951 to Colomina, U.S. Pat. No. 5,290,122 to Hulme, and U.S. Pat. No. 6,285,564B1 to O'brien, describe such wedge locking circuit card retainers. Such wedge locking type retainers are also sold under the trade name "series 226 Card-lock" by Calmark Corporation, of San Gabriel Calif., United States of America.
Screw actuated wedge locking retainers have several disadvantages. The mechanism is somewhat complex, given the simple function to be performed, thereby driving up the cost of the retainers and installation into the chassis. The complexity and necessity for angular movement of the wedges makes this type or retainer larger than is desirable in densely packed electronic chasses. The screw must also typically be made of steel or a high strength alloy, which adds undesirable weight. A pair of oppositely facing surfaces on the chassis is also required, thereby adding undesirable complexity to the chassis.
In another prior approach to securing circuit cards in a chassis, retainers having a plurality of leaf spring members have been utilized. One such leaf-spring type retainer is provided under the trade name "Series nw125 and nw126 Card Retainer" by Calmark Corporation of San Gabriel Calif., United States of America. U.S. Pat. Nos. 3,231,785 and 3,950,057 to Calabro disclose other forms of leaf finger spring retainers.
In some forms of prior leaf spring retainers, such as the Series nw125 and nw126 Card Retainers, by Calmark Corporation, one of the opposing surfaces can be eliminated from the chassis by securing the card retainer to the chassis adjacent to the clamping surface. Right and left handed retainers must be provided, however, depending upon the orientation of the clamping surface with respect to the retainer. Such leaf spring retainers must also typically be made of a high strength material such as stainless steel, or beryllium copper, thereby making them heavier than is desirable. Such leaf spring type retainers are also relatively bulky, consuming more package volume than is desirable. The additional steps of riveting or otherwise attaching the retainer to the chassis also add undesirable expenditures of time and cost during fabrication.
It is desirable, therefore, to provide an improved retainer, apparatus, and method for retaining a circuit card against a clamping surface of a chassis or heatsink.

Retainer and method for holding a circuit card against a clamping surface of a chassis or heatsink


Immersion lithography aberration control systems and methods that compensate for a heating effect of exposure energy in an immersion fluid across an exposure zone are provided. An aberration control system includes actuators that adjust optical elements within the immersion lithography system and a fluid heating compensation module coupled to the actuators. The fluid heating adjustment module determines actuator commands to make aberration adjustments to optical elements within the immersion lithography system based on changes in one or more of a flow rate of the immersion liquid, an exposure dose and a reticle pattern image. In an embodiment, the aberration control system includes an interferometric sensor that pre-calibrates aberrations based on changes in operating characteristics related to the immersion fluid. Methods are provided that calibrate aberrations, determine actuator adjustments and implement actuator adjustments upon changes in operating characteristics to control aberration effects.

1. Field of the Invention
The present invention relates to immersion lithography, more particularly, to providing systems and methods for correcting thermally-induced aberrations due to immersion liquid heating.
2. Related Art
Lithography is a process used to create features on the surface of substrates.
Such substrates can include those used in the manufacture of flat panel displays (e.g., liquid crystal displays), semiconductor wafers, circuit boards, various integrated circuits, print heads, macro/nano-fluidic substrates, and the like. During lithography, a substrate, which is disposed on a substrate stage, is exposed to an image projected onto the surface of the substrate by exposure and projection optical systems located within a lithography apparatus.
The projected image produces changes in the characteristics of a layer, for example, photoresist, deposited on the surface of the substrate. These changes correspond to the features projected onto the substrate during exposure. Subsequent to exposure, the layer can be etched or otherwise processed (e.g., developed in case of the layer being a photoresist layer) to produce a patterned layer. The pattern corresponds to those features projected onto the substrate during exposure. The patterned layer is then used to remove or further process exposed portions of underlying structural layers within or on the substrate, such as conductive, semiconductive, or insulative layers. This process is repeated, together with other steps, until the desired features have been formed on the surface, or in various layers, of the substrate. In the field of immersion lithography the exposure operation is conducted with an immersion liquid, which is typically water, between the last lens element of the projection optics and the substrate. This requires certain design modifications to the apparatus.
Lithographic systems have adjustable optics which allow for the correction of optical wave aberrations of, for example, the projection optics. Adjustments are made for lens heating effects which occur even though the lenses of a projection optics are temperature controlled. The aberration levels are measured and adjusted using both on-system and off-system metering devices such as interferometer based sensors.
Current aberration control systems only deal with slowly changing aberration effects related to lens heating. For example, U.S. Pat. No. 6,563,564, entitled Method of Operating an Optical Imaging System, Lithographic Projection Apparatus, Device Manufacturing method and Device Manufactured Thereby, issued to de Mol et al. on May 13, 2003 relates to lens heating and does not address the heating effect of an immersion fluid. The heating effect on the immersion fluid is instantaneous and dependant upon the delivered dose. As soon as the exposure energy is turned off the heated block of fluid is swept away by the fluid flow through an immersion lithography showerhead. The flowing fluid induces a non-symmetric temperature distribution across the width of the exposure slit which induces aberrations in the image field. The aberrations, such as defocus, change across the width of the field. This kind of instantaneous, non-symmetrical aberration effect is not corrected in current aberration control systems.
What are needed are aberration control systems and methods that effectively address instantaneous, non-symmetrical aberration effects that occur within an immersion lithography system.

Systems and methods for thermally-induced aberration correction in immersion lithography


A second substrate has detection electrodes of a touch panel, each of pixels has a pixel electrode and a counter electrode, the counter electrode is divided into a plurality of blocks, the counter electrodes of the respective divided blocks are commonly provided for the respective pixels of the plurality of display lines in series, and the counter electrodes also serve as scanning electrodes of the touch panel, and a counter electrode selector circuit that selects the counter electrodes. The counter electrode selector circuit includes an address decoder circuit that selects the counter electrodes of the respective blocks for a given period, and a selector circuit that applies a touch panel scanning voltage to the counter electrode of the block selected by the address decoder circuit, and applies a counter voltage to the counter electrodes of the blocks not selected by the address decoder circuit.

1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly to a technique effectively applied to a liquid crystal display device with built-in a touch panel so called in-cell type.
2. Description of the Related Art
A display device having a device (hereinafter referred to also as "touch sensor" or "touch panel") for entering information by the operation of touching (touch pressing operation, hereinafter referred to merely as "touch") a display screen with a user's finger, pen or the like is used for mobile electronic devices such as a PDA or a portable terminal, a variety of home electric appliances, and automated teller machines and so on.
As the touch panel of this type, there has been known a capacitance type that detects a change in a capacitance of a touched portion.
As the touch panel of the capacitance type, a liquid crystal display device having the so-called in-cell type touch panel, which is a liquid crystal display panel with a built-in touch panel function, has been known as disclosed in JP 2009-258182 A.
In the touch panel of the in-cell type, scanning electrodes of a tough panel are configured by dividing a counter electrode (also called "common electrode") formed on a first substrate (so-called "TFT substrate") configuring the liquid crystal display panel.

Liquid crystal display device with touch panel


A digital suture fixation system includes an anchor, an introducer that is attachable to a finger of a person such that at least a distal tip of the finger is available to palpate tissue and identify a landmark within a patient, and a delivery device attached to the introducer. The anchor is removably attached to the delivery device. The anchor is exposed on an exterior of the delivery device and the delivery device is positioned to allow the finger to push the anchor into the landmark.

Intracorporeal suturing of tissue during surgery presents challenges to the surgeon in that the surgeon is called upon to manipulate one or more suturing instruments within the confines of an incision formed in the patient's body. In some cases, the surgeon will use his/her finger(s) to dissect tissue or separate tissue along tissue planes to form a space within the tissue that allows the surgeon to palpate and identify a desired target location for placement of a suture. Often, the space formed in the dissected tissue is opened until it is large enough to receive both the surgeon's finger(s) and the suturing instrument(s). The space provides access to the identified target location where it is desired to place the suture. However, the intracorporeal target location is often disposed at an angle that is difficult to reach and can have a depth that precludes visualization of the target location. Delivering surgical instruments to the target location is challenging when the target location cannot be visualized by the surgeon.


Systems and methods for data separation, which may be employed to receive and process RFID tag data in RF signal environments where multiple RFID tags are tracked, localized and/or employed to transmit information. The disclosed systems and methods may be implemented for data separation in a high density aRFID environment using RFID tags in combination with spatial and/or frequency separation.

As defined by the FCC, an ultra-wideband (UWB) signal is an antenna transmission in the range of 3.1 GHz up to 10.6 GHz at a limited transmit power of −41.3 dBm/MHz with an emitted signal bandwidth that exceeds the lesser of 500 MHz or 20% of the center frequency. UWB signals are currently employed for high-bandwidth, short range communications that use high bandwidth radio energy that is pulsed at specific time instants.
Applications for FCC-defined UWB transmissions include distance-based location and tracking applications, and localization techniques that employ precision time-of-arrival measurements. Examples of such UWB applications include radio frequency identification (RFID) tags that employ UWB communication technology for tracking, localization and transmitting information. Other types of UWB applications include precision radar imaging technology. Inventory tracking has been implemented through the use of passive, active and semi-passive RFID devices. These devices have widespread use, and typically respond to interrogation or send data at fixed intervals.
A high density active radio frequency identification (aRFID) environment can easily exceed 1000 aRFID tags for certain application installations, such as cattle feedlot applications where individual cows are each tagged with an aRFID tag. Currently, aRFID installations such as these may be implemented using a maximum of approximately 1000 aRFID tags per each RFID receiver that is provided for the installation. However, aRFID environments may routinely contain in excess of 40,000 tags within a 1 to 2 sq mile area. One previous attempt that has been made to reliably receive and process tag data, and to perform geolocation calculations in such environments, is to use software-only coding schemes in order to help distinguish between multiple tags. This method typically works up to the point where available bandwidth is exceeded due to the number of bits being transmitted (˜100 bits per tag transmission) and the number of tags in the environment (˜1000). Existing RFID tag geolocation technologies employ RFID tags which typically report data at a fixed rate, which is acceptable for low tag density environments (i.e., tag density less than approximately 1000) where interleaved and colliding packets are not problematic.
Traditional time difference of arrival (TDOA) techniques that are employed to locate emitters, such as transmitting RFID tags, require that the absolute time of arrival (TOA) of an emitted signal at each of two or more receivers be recorded and the difference taken, or require that the two signals be processed using a cross correlation method. The primary source of error in determining the absolute TOA is the accuracy with which the arrival time of the emitted signal may be measured at each receiver. Although a high degree of timing accuracy can, in principal, be obtained by employing highly synchronized clocks at each receiver (e.g., using synchronized atomic clocks), this can be a very expensive option. Use of a cross correlation method is appropriate only for narrow band signals and also lacks a high degree of precision.

Data separation in high density environments

L-3 Communications Integrated Systems L.P.


A device, a system, and/or a method are provided for monitoring the eye behavior of drivers of oncoming cars. A camera mounted to a car mirror may monitor the eyes of oncoming drivers. An eye recognition analyzer may recognize nystagmus symptoms exhibited by the oncoming drivers. A machine may recognize the license plate information of the oncoming cars. The license plate numbers, as well as other identifying features of the oncoming cars, may be displayed on a head-up display of a car. A driver of the car may be otherwise notified by an alarm and/or warning about the possibility of a dangerous, oncoming car. An emitter located on the car may emit signals to other nearby networked cars in order to warn their drivers about the dangerous oncoming car. Information regarding the dangerous oncoming car may be displayed on the head-up displays of the other nearby networked cars.

Traffic-related fatalities are one of the leading causes of death in many countries throughout the world. Many traffic accidents are due to temporary physical incapacitation of the driver. Such physical incapacitation may be, for example, due to the influence of drugs and/or alcohol, the effects of under sleeping, and/or the use of hand-held devices. While harsher punishments may discourage some people from partaking in volatile driving practices, they may not serve as a sufficient deterrent for all people. Oftentimes it is the other driver, who was practicing safe driving, who is injured or killed in accidents due to drunk driving or the like. Thus, the law-abiding citizen may feel powerless against the risk of encountering a nearby driver whose capacity to drive is in some way hindered.
Thus, many systems and devices exist for increasing driver safety. The most obvious of these are airbags and seatbelts. However, recent innovations have been introduced which monitor and/or regulate an under-slept or incapacitated driver's behavior. One example of such innovations is an in-car breathalyzer device which prevents the car from starting unless and until the driver blows and registers legal blood-alcohol content into the device. However, many ways exist to bypass this requirement, such as having another person blow into the device. Moreover, such devices are mainly only imposed upon people with prior driving-while-intoxicated convictions.
Another recent innovation has been devices and systems which monitor a user's eye activity. Such devices warn a driver with a vibration of the seat or steering wheel if they detect the driver to be nodding off while at the wheel. While such innovations are welcome, they do not serve to protect a driver from other nearby cars. No devices or systems exist which warn other drivers and/or police about a possibly incapacitated nearby driver. Such an innovation would be extremely useful because it would be the first to protect a driver from other drivers, as opposed to protecting a driver from himself/herself.
In view of the foregoing, there is a need for a device, system and method for warning other drivers about a possible incapacitated state of a driver a vehicle.

Devices, systems and methods for identifying potentially dangerous oncoming cars


The present invention relates to a method for transmitting frames from a transmitting mesh device to a receiving mesh device in a mesh network, comprising: storing frames received in the transmitting mesh device from a source mesh device and intended for a destination mesh device in a relay queue, the source mesh device and the destination mesh device being different from the transmitting device, storing frames generated by the transmitting mesh device in a local queue, different from the relay queue, selecting a frame from the relay queue or local queue based on a predetermined scheduling strategy, —transmitting the selected frame to the receiving mesh device.

In conventional wireless mesh networks, mesh devices have the ability to perform several types of operations:                forwarding frames received from a source device and intended for a destination device,        consuming frames, received from a source device, and used during sequence of operations of local applications of the device, and        They can generate frames during operating sequences of local applications.
These operations do not mutually exclude each other, which means that applications running on a mesh device may generate frames concurrently to frames that the mesh devices receive and have to forward
In most existing implementations for WMNs, both types of frames, i.e. generated frames and received frames are handled equally when it comes to transmitting them to a receiving node. Indeed, frames of local origin and frames of remote origin are stored in the same transmission queue, and are sorted and transmitted according to their order of occurrence.
However, frames of both origins do not experience the same loss before reaching the transmission queue, depending on their origin. Frames generated by local applications do not traverse a transmission medium and, accordingly, do not experience any frame loss. For these frames, frame dropping occurs only if a lower layer buffer is full, which means that, in most cases, local applications easily store their frames in the local transmission queues.
On the contrary, frames coming from another mesh device have to traverse the wireless medium, which means that they are less likely to be successfully stored in the mesh device's transmission queue, because they may experience frame loss during crossing of the medium. Thus, the transmission queue may contain more generated frames than received ones.
Moreover, transmission rate on the wireless medium is limited, whereas applications locally running at mesh devices may generate frames at a higher rate. Consequently, both the limited incoming traffic rate and the reduced reception success probability of frames received from external devices increase the probability for these frames to be dropped at the transmitting mesh devices.
In addition, if p denotes the frame dropping probability on a single transmission link, the probability of a successful transmission over a chain of n equal and independent links is (1−p)n. Thus, the frame dropping probability increase with every additional hop, which means that frame transmissions of devices that are close to the intended destination experience better performance than frame transmissions that still have to traverse a large number of hops.
Accordingly, it appears that current implementations using equal treatments for both types of frames present major drawbacks in always giving precedence to frames of local origin, thus leading to bad performance of multi-hop transmissions, and also by offering different qualities of service and overall performance to users situated in different locations in the network.

Method of transmitting frames in a mesh network, mesh device and mesh network therefor


The present invention discloses a method of fabricating a thin film in a chamber where a heater and a suscepter are located. The method includes the steps of disposing an object on the susceptor so as to form the thin film thereon; heating the object; a first sub-step of introducing a first gaseous reactant into the first chamber such that the first gaseous reactant is absorbed on the object to form an absorption layer; a second sub-step of introducing a second gaseous reactant into the first chamber such that the second gaseous reactant reacts with the absorption layer absorbed on the object; and a third sub-step of introducing a reducing gas into the first camber such that the reducing gas reduces by-products and impurities of the first and second gaseous reactants.

This application claims the benefit of Korean Patent Applications No. 2001-5043 filed on Feb. 2, 2001, which is hereby incorporated by reference as if fully set forth herein.
1. Field of the Invention
The present invention relates to a method for performing Chemical Vapor Deposition (CVD), and more particularly to Atomic Layer Deposition (AID) Processes.
2. Discussion of the Related Art
In the field of thin film technology requirements for thinner deposition layers, better uniformity over increasingly larger area substrates, larger production yields, and higher productivity have been driving forces behind emerging technologies developed by equipment manufactures for coating substrates in the manufacturing of various semiconductor devices.
Electric devices are recently highly integrated to have smaller size and light weight because of semiconductor devices. Specifically, the manufacture of Ultra Large Scale Integration is possible due to the improved thin film deposition technologies manufacturing the semiconductor devices.
Namely, process control and uniform film deposition achieved in the production of a microprocessor can be achieved. These same factors in combination with new materials also dictate higher packing densities for memories that are available on a single chip or device. As these devices become smaller, the need for greater uniformity and process control regarding layer thickness rises dramatically.
Various technologies well known in the art exist for applying thin films to substrates or other substrates in manufacturing steps for integrated circuits (ICs). Among the more established technologies available for applying thin films, Chemical Vapor Deposition (CVD) is an often-used and commercialized process. Atomic Layer Deposition (ALD), a variant of CVD, is a relatively new technology now emerging as a potentially superior method for achieving uniformity, excellent step coverage, and transparency to substrate size. ALD, however, exhibits a generally lower deposition rate than CVD.
CVD is flux-dependent application requiring specific and uniform substrate temperature and precursors (chemical species) to be in a state of uniformity in the process chamber in order to produce a desired layer of uniform thickness on a substrate surface. These requirements becomes more critical as substrate size increases, creating a need for more complexity in chamber design and gas flow technique to maintain adequate uniformity.
In the CVD method alluded above, deposition rates of thin films and characteristics of deposited thin films depend on circumstances of the process chamber, such as chamber temperature and pressure, accompanying precursor""s flow rate. Another problem in CVD coating, wherein reactants and the products of reaction coexist in a close proximity to the deposition surface, is the probability of inclusion of reaction products and other contaminants in each deposited layer. Also reactant utilization efficiency is low in CVD, and is adversely affected by decreasing chamber pressure. Still further, highly reactive precursor molecules contribute to homogeneous gas phase reactions that can produce unwanted particles which are detrimental to film quality. Therefore, Low Pressure Chemical Vapor Deposition (LPCVD) by which step coverage and uniform thickness of thin film are improved is now in the spotlight in forming thin films on a substrate surface. However, when using LPCVD, the deposition rates decrease, thereby attempting to introduce reaction gases having higher partial pressures. This also causes the problems that gas reactions occur in an undesired position of reaction chamber, so the possibility of contaminants in the deposited layer increases.
On account of above-mentioned problems, Atomic Layer Deposition (ALD) has been researched and developed. Although a slower process than CVD and although the similarity to CVD in using precursor reactions, ALD demonstrates a remarkable ability to maintain ultra-uniform thin deposition layers over complex topology. This is at least partially because ALD is not flux dependent as described earlier with regards to CVD. This flux-independent nature of ALD allows processing at lower temperatures than with conventional CVD rocesses.
ALD processes proceed by chemisorption at the deposition surface of the substrate. The technology of ALD is based on concepts of Atomic Layer Epitaxy (ALE) developed in the late 1970s or early 1980s, for example, U.S. Pat. No. 4,058,430, for growing of polycrystalline and amorphous films of ZnS and dielectric oxides for electroluminescent display devices. The technique of ALD is based on the principle of the formation of a saturated monolayer of reactive precursor molecules by chemisorption. In ALD appropriate reactive precursors are alternately pulsed into a deposition chamber. Each injection of a reactive precursor is separated by an inert gas purge. Each precursor injection provides a new atomic layer additive to previous deposited layers to form a uniform layer of solid film. The cycle is repeated to form the desired film thickness.
A good reference work in the field of Atomic Layer Epitaxy, which provides a discussion of the underlying concepts incorporated in ALD, is Chapter 14, written by Tuomo Suntola, of the Handbook of Crystal Growth, Vol. 3, edited by D. T. J. Hurle, .COPYRGT. 1994 by Elsevier Science B. V. The Chapter title is xe2x80x9cAtomic Layer Epitaxyxe2x80x9d. This reference is incorporated herein by reference as background information.
To further illustrate the general concepts of ALD, an ALD process for forming a film of materials A and B, as elemental materials, will be explained hereinafter. A solid layer of element A is formed over the initial substrate surface, and then a first purge is processed to form a single atomic layer of element A. Over the A layer, a layer of element B is applied, and then, a second purge is performed. Therefore, the layers are provided on the substrate surface by alternatively pulsing a first precursor gas A and a second precursor gas B into the region of the surface, resulting in providing the AB solid material.
Meanwhile, gaseous reactants and their bonding energy are dependant on a substrate and a material which are under the deposited thin films. When forming a single-crystalline layer on a surface of single-crystalline silicon substrate, there are a lot of active portions which are distributed uniformly on that silicon substrate surface and on which gaseous reactants are deposited. By way of applying a thermal energy to the gaseous reactants with maintaining the substrate at a high temperature, gaseous reactants are uniformly deposited and decomposed in the surface of substrate, and thus, silicon atoms are rearranged and grow to a single-crystalline thin film in accordance with the single-crystalline surface of the substrate. At this time, the physically deposited gaseous reactants exist on the chemically deposited silicon layer provided on the substrate surface, and thus such gaseous reactants act as impurities and contaminants that decrease purity of deposited layer. Therefore, a purge process proceeds after such a depositing process. Namely, the substrate heated with the aid of a suitable heating source is subjected to the gaseous reactants, and then purged using an inert gas. Therefore, the chemically deposited reactants are left on the substrate, whereas the physically deposited reactants are removed from the substrate, resulting in forming a single atomic silicon layer on the single-crystalline silicon substrate.
This type of procedure is also disclosed in U.S. Pat. No. 4,389,973, for example. According to that patent, the wafer is sequentially subjected to a plurality of gaseous reactants in order to form thin films thereon. During the deposition processes, the gas phase diffusion barrier is used as a carrier gas in order to prevent reactions between source gases, or the carrier gas is used to remove the residual gases after injecting each source gas.
U.S. Pat. No. 4,767,494, as another example, discloses the compound semiconductor thin film formed by growing a plurality of molecular layers one over another. According to that invention, while a carrier gas and a small quantity of hydride containing an element in Group V or VI are normally flowed, an organometallic compound which is diluted with hydrogen and which contains an element in Group V or VI and a hydride which is diluted with hydrogen and which contains an element in Group V or VI are alternately introduced over a substrate so that an atomic layer of an element in Group III or II and an atomic layer of an element in Group V or VI are alternately grown over the substrate. Therefore, grown layers having a high degree of purity can be obtained.
In U.S. Pat. No. 5,130,269, the method of growing a gallium arsenide single crystal layer on a silicon substrate comprises steps of growing a buffer layer of aluminum arsenide on the silicon substrate by Atomic Layer Epitaxy (ALE), and growing the gallium arsenide single crystal layer on the buffer layer epitaxially.
As known from the above-mentioned patented invention, ALD has been developed to overcome the drawback of CVD, so that ALD in resent obtains better uniformity over increasingly large area substrates and excellent step coverage. Contrary to CVD where gaseous reactants simultaneously flow into a reaction chamber to deposit thin films on a substrate, ALD alternately subjects the substrate to gaseous reactants, and includes an inert gas purge process to remove residual gases, thereby dropping the impurity content in the deposited layers. For example, when forming a thin film on a substrate using two vapor phase reactants, one cycle of the gas sequence for the growth of the thin film includes four sub-steps. In a first sub-step, a first vapor phase reactant is introduced into a reaction chamber in which a substrate is positioned. Thereafter, residual gas is removed from the reaction chamber, i.e., a second sub-step. In a third sub-step, a second vapor phase reactant is introduced into the reaction chamber to form a thin film with the first layer formed of the vapor phase reactant. In a four sub-step, residual gas is removed again from the reaction chamber. This conventional ALD technology is disclosed in U.S. Pat. Nos. 4,413,022 and 6,015,590. As a method for removing the residual gas, the inert gases are used in U.S. Pat. No. 4,413,022, and the vacuum pump is adopted according to U.S. Pat. No. 6,015,590.
FIG. 1 is a graph illustrating one cycle of forming a thin film using a conventional ALD technology. In FIG. 1, one cycle T of forming a thin film includes a first quantity t1 representing the time during the first sub-step, a second quantity t2 representing the time during the second sub-step, a third quantity t3 representing the time during the third sub-step, and a fourth quantity t4 representing the time during the fourth sub-step. The time quantities t2 and t4 over which the residual gases are removed are longer than the time quantities t1 and t3 over which the substrate is objected to the gaseous reactants. As a result, the process of forming a thin film needs a sufficiently long time, and manufacturing yield of thin film is reduced.
At this point, a lot of methods and plans are introduced to reduce the time required in each sub-step. However, the time quantities t1 and t3 should maintains for a sufficient time because these should be enough to distribute and absorb the injected gaseous reactants over the whole surface of the substrate. Furthermore, it is difficult to reduce the time quantities t2 and t4.
For example of applying the above-mentioned ALD method, a process of forming an alumina (Al2O3) film using the conventional ALD is presented in Applied Physics Lettersxe2x80x94Volume 71, No. 25, pp. 3604-3606, Dec. 22, 1997. At a deposition temperature of about 370 degrees centigrade (xc2x0 C.), tri-methyl-aluminum [Al(CH3)3, TMA] is introduced into the reaction chamber during the first sub-step t1 of about one second under the pressure of about 230 mTorr. Then, the introduction of TMA is stopped, and Ar gas is introduced into the reaction chamber during the second sub-step t2 of about 14 seconds. The above-mentioned Ar gas prevents the TMA from being over-adsorbed on the silicon substrate, and discharges a residual non-reacting gas out of the reaction chamber. Thereafter, a de-ionized water (DIW) vapor is introduced into the reaction chamber during the third sub-step t3 of about 1 second under the pressure of about 200 mTorr. Subsequently, the introduction of TMA is stopped, and Ar gas is introduced again into the reaction chamber during the fourth sub-step t4 of about 14 seconds such that another residual non-reacting gas is discharged out of the reaction chamber.
After one cycle, specifically 30 seconds, during the above-mentioned process, the obtained film is less than 0.3 nm in thickness. Therefore, for the fabrication of 10 nm film, the above-mentioned cycle should be repeated for about 33 times. In other words, it takes more than 990 seconds to fabricate the 10 nm film by applying the ALD. Accordingly, although the use of the conventional ALD method can produce a thin film having a low-impurity content, it takes longer processing time while depositing the film on the substrate.
Meanwhile, if a substrate or a underlayer is polycrystalline or amorphous, the energy level of active portion varies depending on substrate""s or underlayer""s crystal structure and surface state because the active portions on which the gaseous reactants are deposited exist in a various state. Therefore, when the gaseous reactants are objected to the substrate or underlayer, the active portion""s position and the binding energy are determined by the gaseous reactant type. At this point, as mentioned before, the physically deposited reactants are cleaned from the reaction chamber in accordance with the quantity of injected inert gas and the chamber pressure or the vacuum pump capacity. However, at the time of that cleaning process, the chemically deposited reactants can be exhausted from the substrate or underlayer if the binding energy is weak in the active portion. Therefore, the layer thickness, which is obtained during one cycle, is various depending on the process condition although the gaseous reactant is the same. To obtain a determined thickness, thus, the deposition process alluded before should be repeated a lot more times. This results in increasing depositing time and decreasing manufacturing yield.
As mentioned before, in the CVD method, a lot of gaseous reactants are injected into the reaction chamber and converted into radicals, thereby forming thin films by interactions of radicals. At this time of forming the thin films, by-products are produced and then trapped into the deposited layers due to the continuous apply of gaseous reactants.
However, in case of the ALD method, after introducing the gaseous reactants to the substrate, the purge process is repeatedly performed over each reactant introduction. Therefore, the impurity concentration in the deposited layer and the layer thickness over one cycle are determined in accordance with the quantity of inert gas and the time consumption. Furthermore, the hourly productivity is varied by these inert gas quantity and the time passage. In other words, when the inert gas quantity increases and when it takes longer processing time to purge the active portion and to pump down the reaction chamber for the purpose of decreasing the impurity ratio from the layer, the adhered reactants are rapidly reduced due to the removal of deposited elements. These cause the decrease of layer thickness less than single atomic layer and produce the inferior production, thereby deteriorating the hourly productivity. Moreover, due to the injecting and purge processes, there are other problems of shifting gas injection devices, and thus, the time delay is unfortunately caused, and productivity is further declined. To overcome these problems, the complex facilities having various equipments and devices are recommended, but those facilities increases the production cost in the field of semiconductor devices.
Accordingly, the present invention is directed to a method of forming a thin film that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a method of forming a thin film, which presents an excellent step coverage, a uniform layer composition and a high degree of purity in the thin film.
Another object of the present invention is to provide a method of forming a thin film, which has a short processing time of layer deposition.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to achieve the above object, the preferred embodiment of the present invention provides a method of forming a thin film in a first chamber where a heater and a suscepter are located. The method includes the steps of disposing an object on the susceptor so as to form the thin film thereon; heating the object; a first sub-step of introducing a first gaseous reactant into the first chamber such that the first gaseous reactant is absorbed on the object to form an absorption layer; a second sub-step of introducing a second gaseous reactant into the first chamber such that the second gaseous reactant reacts with the absorption layer absorbed on the object; and a third sub-step of introducing a reducing gas into the first camber such that the reducing gas reduces by-products and impurities of the first and second gaseous reactants.
In one aspect, the first, second and third sub-steps are sequentially repeated as one cycle so as to form the thin film having an ultra-high degree of purity. A thickness of the thin film having the ultra-high degree of purity is 0.3 nm after performing the first and second sub-steps one time. The thin film having the ultra-high degree of purity is 10 nm in thickness after final deposition process.
In another aspect, three-time repetitions of the first and second sub-steps and one time of the third sub-step form one cycle of deposition and several repetitions of one cycle form the thin film having a high degree of purity. A thickness of the thin film having the high degree of purity is 1 nm after three-time repetitions of the first and second sub-steps. A thickness of the thin film having the high degree of purity ranges from 0.2 to 0.3 nm after one time of the first and second sub-step. The thin film having the high degree of purity is 10 nm in thickness after final deposition process.
In another aspect, more than ten-time repetitions of the first and second sub-steps and one-time of the third sub-step form one cycle of deposition and several repetitions of one cycle form one of crystalline and amorphous thin films. A thickness of each of crystalline and amorphous thin films ranges from 2 to 3 nm after one cycle of deposition. Each of crystalline and amorphous thin films is 10 nm in thickness after final deposition process. A thickness of each of crystalline and amorphous thin films ranges from 0.2 to 0.3 nm after performing the first and second sub-steps one time.
In the above-mentioned method, the first and second sub-steps form an oxidized layer and the reducing gas is one of oxygen and ozone. The first and second sub-steps form a nitride layer and the reducing gas is one of ammonia and hydrazine.
The above-mentioned method further includes the step of thermal-treating the object in a second chamber after the third sub-step when the deposited thin film is used as a dielectric layer for the electric device. The second chamber is a vacuum chamber and the reducing gas of the third sub-step is introduced in the second chamber. The reducing gas introduced in the second chamber is excited into a plasma during the thermal treatment for the dielectric layer. The dielectric layer is one of alumina thin film and tantalum pentoxide (Ta2O5) thin film. The method further includes the step of forming a polycrystalline silicon layer on each of alumina thin film and tantalum pentoxide (Ta2O5) thin film. Forming one of alumina thin film and tantalum pentoxide (Ta2O5) thin film and forming the polycrystalline silicon layer are sequentially performed in the first and second chamber.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Thin film deposition method including using atomic layer deposition without purging between introducing the gaseous reactants


An "extra-folded" projection display system includes a selectively reflective material (e.g., a linear reflecting polarizer) placed immediately behind the system's imaging screen. The display system includes an image projector that projects an image beam containing light of a predetermined linear polarization toward the imaging screen. The linear reflecting polarizer reflects the light in the image beam away from the screen. The reflected image beam then encounters a 1/4-wavelength achromatic retarder which converts the linear polarization to circular polarization. The image beam next hits a mirror that reflects the light back through the 1/4-wavelength achromatic retarder, which converts the circular polarization back to linear polarization, with the polarization director rotated 90.degree. from the original polarization director. The linear reflecting polarizer then allows the light to pass through to the image screen.

1. Field of the Invention
The invention relates to projecting images.
2. Description of the Related Art
Referring to FIG. 1, light projectors are used, for example, to display images on large surfaces, such as movie or television screens. In a front projection system 20, an image beam 24 is projected from an image source 21 onto the "front" side of a reflection-type angle transforming screen, which then reflects the light toward a viewer 27 positioned in front of the screen. In a rear projection system, the image beam is projected onto the "rear" side of a transmission-type angle transforming screen 26 and transmitted toward a viewer 29 located in front of the screen.
Due to the physical properties of light, the size of the image beam 24 when it reaches the screen 26 depends upon the magnification rate of the image source 21 and the distance between the screen 26 and the image source 22. To efficiently utilize the screen 26, the image beam 24 should just fill the entire height S and width (not shown) of the screen 26. In FIG. 1, the image beam 24 fills the screen 26 when the source 22 is at an appropriate distance D from the screen 26, i.e., when the center of the image beam 24 follows an optical path 28 of length D. The optical path length D depends upon the screen height S and the magnification rate of the image source. Any non-transparent object placed in the path of the image beam 24 typically will obstruct the image beam 24 and form a shadow on the screen 26.
Referring to FIG. 2, designers have reduced the size of the typical image projection system 30 by "folding" the optical path of the projected image beam to reduce the apparent projection length L of the system 30. The "folded" system 30 includes one or more mirrors 34, 36 placed at strategic points along the optical path to redirect the projected image and to form multiple optical subpaths D1, D2, D3. The overall system configuration in this optical system 30 is more rectilinear than the conical system configuration of FIG. 1.
In the folded image projection system 30, assuming that the image source 40 and the screen 32 are similar to those in FIG. 1, the image 38 fills the screen 32 entirely when the mirrors 34, 36 are positioned such that the combined length of the optical subpaths D1, D2, and D3 equals the optical path length D in FIG. 1, even though the apparent projection length L is less than D.