A method of thinning SOI films for providing ultra-thin active device regions having excellent thickness uniformity and further having self-aligned isolation regions between the active device regions is disclosed. A substrate having an isolation layer formed thereon and further having a single crystal silicon layer formed upon the isolation layer is first provided. A thermal oxide layer is grown upon the silicon layer, patterned in desired regions corresponding to polish stop regions positioned between predetermined active device regions, and etched. The silicon layer is thereafter etched according to the patterned thermal oxide layer with a high selectivity etch, thereby creating grooves in the silicon layer. An insulative polish stop material is then deposited upon the thermal oxide, silicon, and isolation layers, the polish stop material forming top, sidewall, and bottom polish stop material thereon, respectively, partially filling the grooves, and further wherein the bottom polish stop material comprises a prescribed thickness. Polysilicon is deposited upon the polish stop material to further completely fill the grooves and then is planarized down to the top polish stop material. The top polish stop material and the oxide layer are then etched away. Lastly, by chemical-mechanical polishing, the silicon, sidewall polish stop material, and polysilicon are thinned down to the bottom polish stop material, whereby active device regions have uniform thickness corresponding to the thickness of the bottom polish stop material.

1. Field of the Invention
This invention generally relates to silicon-on-insulator films and, more particularly, to a method for thinning an SOI film having improved thickness uniformity.
2. Discussion of the Related Art
It has been demonstrated by 2D simulations and experiments that thinning SOI films to less than the maximum depletion depth in the channel region (that is, approximately 1000.ANG. or less) brings about remarkable device properties as described in M. Yoshimi, et al., "Electrical Properties and Technological Perspectives of Thin-Film SOI MOSFETs", IEICE Trans., Vol. E74, No. 2, Feb. 1991, pp. 337-351. In ultra-thin SOI, the device body becomes fully depleted which results in greatly improved short channel characteristics at much lower channel dopings. This also increases the device turn-on voltage, i.e., threshold voltage (V.sub.T), tolerance to body doping and channel length. In addition, full depletion produces near ideal subthreshold slope, nearly 45% improved transconductance and much higher current drivability. This in conjunction with reduced junction capacitances yields greater switching speed with thin SOI CMOS than in comparable bulk Si CMOS. These properties of ultra-thin SOI CMOS open superior possibilities for scaling CMOS structures in the deep sub-half .mu.m regions that are impossible with conventional bulk silicon.
SOI films with thickness near 1000.ANG. can be made using SIMOX (Separation by IMplantation of OXygen) technology. However, SIMOX/SOI wafers suffer from high defect density (>1000 per cm.sup.2). Also, the cost of commercially available thin SIMOX/SOI is very high. On the other hand, wafer bonding and polishing produces defect-free SOI films at much lower cost. However, the minimum SOI thickness achievable with the present commercial wafer bonding technology is about 2 .mu.m with thickness uniformity of about .+-.3000.ANG.. Therefore, thinning the commercially available bonded SOI wafers to the thickness required for fully depleted CMOS (i.e., <1000.ANG.) is an attractive approach for producing ultra-thin near-zero defect SOI material. A method for thinning SOI films having excellent thickness uniformity is highly desirable. Furthermore, a method for producing ultra-thin active device regions having self-aligned isolation regions is highly desirable.

Method for thinning SOI films having improved thickness uniformity

International Business Machines Corporation


An isolator mount for the active dissipation of shocks and vibrations is presented. The invention includes at least one energy dissipating element disposed between deflectable elements so as to provide soft damping for small disturbance excitations, yet remaining sufficiently stiff to mitigate large shocks. The mount transfers mechanical energy to the dissipating element via the device structure. Dissipating element mitigates the energy in shocks and vibrations as either heat or magnetic energy. A snap-together modular embodiment enables the coupling of two or more isolators for use within a wide variety of shock and vibration applications. Quasi-static tuning of one or more mounts comprising a snap-together module facilitates an active response to changing conditions.

1. Field of the Invention
The present invention generally relates to an isolator mount. Specifically, the invention includes an alloy or rare earth integrated within an active-mode isolation mechanism so as to impede both shocks and vibrations. Methods of manufacture are described facilitating the integration of alloys and rare earths within a plastic, composite, and metal.
2. Related Arts
Naval ships employ a wide variety of isolator mounts to impede acoustic transmissions and to protect sensitive equipment from shocks and vibrations. Presently, isolator mounts are specifically designed for a limited range of shocks and vibrations. As such, a variety of mounts are required to satisfy a wide range of mechanical load conditions.
Energy dissipation mechanisms employed within presently known devices quickly degrade with use thereby requiring frequent replacement. For example, passive mounts comprised of rubber and metal rapidly lose their damping capacity. Consequently, isolator mounts are often used well beyond their effective lifetime thereby compromising the integrity and performance of shipboard systems.
Active mounts with integrated electronics increase the range of shocks and vibrations effectively isolated. However, active mounts are generally less durable and sensitive to environmental conditions. For example, wires externally attached to such devices are susceptible to breakage. Furthermore, electronics within such devices are susceptible to the very shocks and vibrations dissipated and to damage by saltwater, ozone, and oil contaminants.
Low-frequency shocks, typically from 3 to 10 Hz, and vibrations, typically from 5 to 30 Hz, exclude many passive and active damping devices. For example, the effectiveness of viscoelastic damping increases with frequency and is therefore of limited utility at low frequencies. Passive damping by piezoelectric or electrostrictive devices, also referred to as direct effect damping devices, is not particularly useful at low bandwidths since damping is dependent upon hysteresis loops and elastic-mechanical-to-electrical energy coupling. Coupling coefficients are generally poor and total loss is insignificant at the lower dynamic range.
Piezopolymers are better direct coupling materials than piezoceramics and electrostrictors, therefore applicable to piezo-passive damping devices. In a passive-mode device, a generalized matched impedance circuit is coupled to the active ferroelectric materials so as to transfer elastic energy to heat. In a semi-active mode, the circuit is variably tunable. However, strength and stiffness characteristics preclude the use of ferroelectric polymers, such as PVDF and urethane, as active devices.
What is required is an isolator mount possessing both soft damping for small disturbance excitations and stiffness to mitigate large shocks.
What is required is an isolator mount having a high level of damping effective against shocks and vibrations yet which remains sufficiently stiff otherwise.
What is required is an isolator mount that functions over a wide range of temperature and load conditions.
What is required is an isolator mount that facilitates quasi-static tuning for adaptive passive damping.


A recording medium has a management area and a data area. Information pertaining to recording reservation is recorded in the management area so as to be displayable in the form of an image. A recording/playback apparatus for recording and reproducing information with respect to the recording medium reads out information pertaining to recording reservation from the recording medium and executes reservation recording on the basis of the information that is read out.

The present invention relates to a recording medium and recording/playback apparatus capable of recording and reproducing recording reservation information and, more particularly, to an apparatus which can be effectively incorporated into a digital video disk recording/playback apparatus.
As is well known, moving picture optical disk playback apparatuses capable of reproducing optical H disks recording, e.g., video and audio data have been developed recently. For example, LDs (Laser Disks) and video CDs (Compact Disks) are finding widespread use for movie software, karaoke, and the like.
At present, a DVD (Digital Video Disk) video standard based on an AC-3 audio compression method has been proposed by using the internationally standardized MPEG (Moving Picture Image Coding Experts Group) 2 method.
This DVD video standard supports MPEG2 as a moving image compression method and AC-3 audio, MPEG audio, and linear PCM (Pulse Code Modulation) as audio compression methods in accordance with MPEG2 system layers. Additionally, the DVD video standard includes sub-picture data, for a caption, which is obtained by run-length-compressing bitmap data, and control data (navigation data) for special playback such as fast forward playback and fast rewind playback.
This DVD video standard also supports ISO (International Organization for Standardization) 9660 and micro UDF (Universal Disk Format) to allow computers to read data.
After that, a DVD-RAM (Random Access Memory) has been announced and rewritable optical disks having capacities such as 2.6 Gbytes (Gigabytes) and 4.7 Gbytes have been realized.
These technologies are beginning to realize recording and playback of video signals with respect to optical disks.
Meanwhile, VTRs (Video Tape Recorders) are currently widely used as means for recording video and audio signals. These VTRs have very high cost performance because the running cost with respect to the recorded information amount is low.
On the other hand, an optical disk as a recording medium represented by a DVD-RAM is required to be able to record computer data and disk management information in addition to video data.
It is expected by using the superiority of a disk over a VTR to realize new functions which have been impossible.
One of these new functions is program reservation recording. To realize this reservation recording, recording reservation must be performed before that. Conventionally, various improvements such as a G code system have been made to simplify recording reservation. However, settings for recording reservation are. still considerably cumbersome.
Additionally, to make a collection of a certain program by sequentially recording episodes of the program in a single optical disk, it is necessary to perform inefficient operations of managing the correspondence between optical disks and such programs and performing recording reservation each time a program of interest is broadcast.
The present invention has been made in consideration of the above situation, and has as its object to provide a recording medium which can record reservation (recording reservation) information of recording, i.e., recording reservation information or by which a recording/playback apparatus automatically starts up in accordance with reservation information and performs reservation recording.
It is another object of the present invention to provide a recording/playback apparatus which accesses the recording medium and records or reproduces reservation information.
It is still another object of the present invention to provide a recording/playback apparatus capable of accessing a recording medium and performing reservation recording on the basis of reservation information recorded on the recording medium.
A recording medium according to the present invention has a management area and a data area. Information pertaining to recording reservation is recorded in the management area so as to be displayable in the form of an image.
Also, a recording/playback apparatus according to the present invention records and reproduces information with respect to a recording medium. The apparatus includes control means for reading information pertaining to recording reservation, which is recorded on the recording medium so as to be displayable in the form of an image, and executing a reservation recording operation on the basis of this information.
In the above arrangements, the information pertaining to recording reservation is recorded on the recording medium. Therefore, reservation recording of a program can be efficiently performed with a high degree of freedom.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.

RECORDING MEDIUM AND RECORDING/PLAYBACK APPARATUS CAPABLE OF RECORDING AND REPRODUCING RECORDING RESERVATION INFORMATION AND ADDITIONAL INFORMATION INDICATING WHETHER THE RECORDING RESERVATION INFORMATION IS VALID


An n-type channel diffused layer and an n-type well diffused layer are formed in the top portion of a semiconductor substrate, and a gate insulating film and a gate electrode are formed on the semiconductor substrate. Using the gate electrode as a mask, boron and arsenic are implanted to form p-type extension implanted layers and n-type pocket impurity implanted layers. Fluorine is then implanted using the gate electrode as a mask to form fluorine implanted layers. The resultant semiconductor substrate is subjected to rapid thermal annealing, forming p-type high-density extension diffused layers and n-type pocket diffused layers. Sidewalls and p-type high-density source/drain diffused layers are then formed.

The present invention relates to a semiconductor device and a fabrication method for the same. In particular, the present invention relates to a semiconductor device that can be made finer and also has shallow-junction, low-resistance diffused layers, and a fabrication method for such a semiconductor device.
With the tendency of higher integration of semiconductor integrated circuits, finer MIS transistors have been demanded. To respond to this demand, MIS transistors having shallow-junction, low-resistance extension diffused layers are required.
A conventional fabrication method for a semiconductor device will be described with reference to FIGS. 9A to 9E (see Japanese Laid-Open Patent Publication No. 2002-76136, for example).
FIGS. 9A to 9E are cross-sectional views for sequentially illustrating process steps of a conventional fabrication method for a semiconductor device.
In the step shown in FIG. 9A, arsenic (As) ions and phosphorus (P) ions as n-type impurities are implanted in a p-type semiconductor substrate 200. The resultant substrate is subjected to heat treatment, to form an n-type channel diffused layer 203 containing arsenic impurities in the top portion of the semiconductor substrate 200 and an n-type well layer 204 containing phosphorus impurities in a portion under the n-type channel diffused layer 203.
In the step shown in FIG. 9B, a silicon oxide film and a polysilicon film are sequentially formed on the resultant semiconductor substrate 200, and then patterned by photolithography and dry etching, to form a gate oxide film 201 and a gate electrode 202.
In the step shown in FIG. 9C, As ions as n-type impurities are implanted in the semiconductor substrate 200 using the gate electrode 202 as a mask, to form n-type pocket implanted layers 207A. Subsequently, boron (B) as p-type impurities are implanted in the semiconductor substrate 200 using the gate electrode 202 as a mask, to form p-type extension implanted layers 206A.
In the step shown in FIG. 9D, a silicon nitride film is deposited over the entire top surface of the semiconductor substrate 200 and then etched by anisotropic etching, to form sidewalls 208 on the walls of the gate electrode 202.
In the step shown in FIG. 9E, boron difluoride (BF2) molecular ions as p-type impurities are implanted in the semiconductor substrate 200, to form high-density source/drain implanted layers. The resultant substrate is subjected to high-temperature, short-time heat treatment, to form p-type high-density source/drain diffused layers 205, p-type extension diffused layers 206 and n-type pocket diffused layers 207.
In the conventional fabrication method for a semiconductor device, the boron implantation energy for formation of the p-type extension implanted layers 206A is made lower than usual in the process of forming the p-type extension diffused layers 206, to thereby attain a shallow junction.
As described above, in the conventional fabrication method for a semiconductor device, boron is implanted in the semiconductor substrate 200 under low-energy, high-dose implantation conditions, to form the p-type extension implanted layers 206A having a shallow junction.
The conventional method described above however has a problem as follows. During the high-temperature, short-time heat treatment performed after the boron implantation, boron in the semiconductor substrate 200 is subjected to a phenomenon of transient enhanced diffusion (hereinafter, referred to as TED). Due to the TED, boron is diffused deep into a region beyond a predetermined junction in the semiconductor substrate 200, and this results in failure to give a desired impurity profile to the p-type extension diffused layers 206. The transient enhanced diffusion (TED) as used herein refers to an abnormal diffusion phenomenon in which impurity atoms interact with excessive point defects such as interstitial silicon atoms and atomic vacancies existing in the semiconductor substrate, resulting in enhancement of diffusion of the impurity atoms. The excessive point defects are mainly introduced by implantation damage occurring during ion implantation in many cases.
Hence, in the conventional fabrication method for a semiconductor device described above, even though the ion implantation energy is lowered to attain a shallower junction, the TED of implanted dopants increases. Therefore, it is difficult to form MIS transistors having shallow-junction, low-resistance extension diffused layers only by implanting ions of a single element at a low energy.

Semiconductor device and fabrication method therefor

Matsushita Electric Industrial Co., Ltd.


The present invention refers to pharmaceutical formulations based on lipids for ophthalmic use comprising a phospholipid component composed of zwitterionic phospholipids of natural origin and an oily component composed of oils of natural origin emulsified in water. In particular, the invention refers to ophthalmic formulations useful, for example, for transporting drugs to the eye and in the treatment of ocular dryness, capable of restoring the lipid layer of the tear film. In particular, in a non-transitory but pathological situation such as the dry eye syndrome, such formulations also succeed in reducing the often-present inflammatory component.

It is known that the function of the tear film is that of keeping the ocular surface wet, protecting the corneal and conjunctival epithelium and transporting biologically active substances which are useful for the physiology of the eye (nutrients, oxygen). To preserve the physical characteristics of the ocular epithelium, the tear film must have a proper surface tension (proper capacity of the mucous layer to permits the aqueous phase to be extended on the epithelium) and must have a physiological evaporation speed. The alteration of these properties determines the rise of ocular dryness and possibly dry eye syndrome.
The tear film is substantially composed of three layers. The first adheres to the ocular surface (cornea, conjunctiva) and is mainly composed of mucin; the intermediate layer is substantially composed of an aqueous solution containing ions, proteins etc.; the third layer, in contact with the air, is mainly composed of non-polar and polar lipids of different nature (cholesterol, cholesterol esters, phospholipid triglycerides, ceramides, cerebrosides etc.) having the function of avoiding a sudden evaporation of the intermediate aqueous layer.
In reality, such layers are in dynamic equilibrium with each other, due to the eyelid blinking, which causes an overall more complex and homogenous tear film.
One cause of the onset of ocular dryness and in particular of dry eye is the excessive evaporation of the aqueous layer of the tear film caused by a poor functionality of the outer lipid layer following qualitative-quantitative modifications of its composition.
Ophthalmic compositions are on the market containing polymers which reduce the evaporation of the tear film due to a certain viscosity level.
Other compositions based on phospholipids or oil emulsions in water are used in order to restore the natural lipid layer of the tear film, always with the function of reducing the evaporation of the aqueous film. These compositions are for instance reported in the Glonek patent, U.S. Pat. No. 5,578,586.
In particular, the aforesaid patent describes a specific and metastable formulation, composed of a phospholipid component and an oily component, at determined concentrations and ratios thereof emulsified in water.
In the indicated patent, the phospholipid component is composed of charged phospholipids (net positive or negative charge) in quantities in the range of 0.01%-7% by weight on the total weight of the composition, while the oily component is composed of mineral oils in quantities between 0.1%-12.5% by weight on the total weight of the composition.
The patent specifies, in particular, that this oil type, defined "non-polar", is preferred to that of animal or vegetal origin, defined "polar" (since they contain a significant number of acid and/or ester groups), since the latter would cause undesired effects of sight dimming and composition instability with respect to synthetic oils.
It should be noted that, with regard to the phospholipids, zwitterionic molecules such as phosphatidylethanolamine and phosphatidylcholine (lecithin) are explicitly excluded from the scope of U.S. Pat. No. 5,578,586, since they are provided with a positive charge which, at pH 7, cancels the negative charge of the phosphate group. Negatively-charged phospholipids are preferred according to this patent, as the negative charge which they impart would facilitate, by a light electrostatic repulsion with the ocular surface negatively-charged, the extension of the composition on the ocular surface.
Moreover, all formulations containing lipids which are available on the market today require being preserved at low temperature (4° C.) due to the poor stability of the lipid component which grows rancid at room temperature.

Pharmaceutical formulations based on apolar and polar lipids for ophthalmic use


A rain head is disclosed having three filters through which water entering an inlet to the rain head must pass before passing out through an outlet from the rain head. The filters remove successively smaller particles from the water.

This invention relates to a rain head. Rain heads are located adjacent the underside of a roof gutter and are attached to an upper end of a downpipe. Rain heads are designed to provide a "safety break" between the downpipe and the roof gutter. This safety break ensures that in the event of a downpipe blockage or rain head blockage from the gutter, water can escape and spill onto the ground and thus prevent flooding of the eaves, wall cavity and the building.
When water from a roof of a building is captured for use and storage in a holding tank the quality of water is reduced by coliforms from animal matter and by turbidity.
Coliforms are the result of animal matter entering the tank whilst turbidity is a result of suspended solids like fine dust particles and vegetable matter.
In an attempt at reducing the presence of coliforms and reducing turbidity, known rain heads usually incorporate a single filter to exclude particles down to a size of about 955 microns. This is usually achieved by stainless steel mesh.
Screening in known rain heads is not particularly effective and these rain heads readily become blocked if not cleaned at relatively short intervals. Once a rain head becomes blocked, water which would otherwise be collected in the holding tank is lost.


A pattern forming method comprises subjecting a surface of a semiconductor substrate to a surface treatment for imparting hydrogen atoms, irradiating a desired region of said surface with an energy ray, selectively forming a metal film on a non-irradiated region other than the desired region, and etching said semiconductor substrate using said metal film as a mask.

1. Field of the Invention
This invention relates to a pattern forming method used in fabricating semiconductor devices. More particularly, it relates to a method of forming a pattern serving as an etching mask, and a method of preparing a photomask for photolithography.
2. Related Background Art
Organic resists have been conventionally used when fine processing is carried out. Using the organic resists as masks, desired patterns are formed by dry etching or the like. Here, in the formation of organic resist fine patterns serving as masks, the processing dimension of organic resists would be limited to of 0.15 .mu.m at best even with an improvement in photomasks used, an improvement in energy ray irradiation apparatus and an improvement in the organic resists.
When the organic resists are developed, the processing size would slightly deviate from the desired size. Accordingly, in photolithography hitherto widely used in VLSI processes, it has been very difficult to control the processing dimension of the organic resists in a good precision of as fine as 0.1 .mu.m or less.
Meanwhile, in photolithographic techniques, photomasks previously provided with patterns of diffusion regions, separating regions, wiring, contact holes, etc. to be formed on a wafer are used and these patterns are successively optically transferred to wafers while keeping their mutual overlap precision. As a system for transferring the patterns on the masks to a wafer, a reduction projection exposure system called a stepper is prevalent at present. In the stepper, patterns on reticles (masks for the stepper are particularly called reticles) are reduced to 1/5 and transferred onto a wafer. At present, it has become possible to transfer a pattern with a width of 0.5 to 0.8 .mu.m onto a wafer at a positional precision of 0.2 .mu.m or less. At this time, the standards of dimensional precision, positional precision, etc. required for light-screening film patterns on the reticle are considered to be values obtained by subtracting errors occurring when patterns are transferred onto a wafer, from the precision actually acceptable on a wafer.
Now, a dimensional error tolerable in a reticle dimension will be estimated, which is intended for an example in which a pattern with a width of 0.5 .mu.m is formed on a wafer at a dimensional precision of .+-.10%. Assume that there are three kinds of dimensional variation factors in a process of forming the pattern onto a wafer, i.e., i) errors in reticle dimension, ii) a resist pattern formation step and iii) an etching step, and their contributions are 1/3 each, the dimensional variation error tolerable as a reticle dimensional error comes to be .+-.0.08 .mu.m around 2.5 .mu.m.
In the meantime, as a method of forming light-screening film patterns on the reticle, electron beam (hereinafter "EB") photolithography is prevalent, this is a process making use of an EB exposure apparatus as an exposure system. Its formation process and main factors of dimensional variations of the light-screening film pattern in each step are shown below.
1. Polishing and washing a light-transmissive substrate (surface flatness, scratches). PA1 2. Depositing a light-screening film on the light-transmissive substrate (layer thickness, adhesion). PA1 3. Coating an EB resist on the light-screening film (layer thickness, sensitivity). PA1 4. Exposure using the EB exposure apparatus (beam precision, amount of exposure). PA1 5. Development of the EB resist exposed (rate of development). PA1 6. Etching of the light-screening film by using the EB resist pattern as an etching mask (difference in pattern conversion).
As shown above, in the conventional EB photolithography, a pattern of highly precise electron beams irradiated from an EB exposure apparatus is first shed on an EB resist to cause a chemical change in the EB resist, and then development is carried out to convert it into an EB resist pattern. Next, using as an etching mask the EB resist pattern thus formed, the light-screening film is etched to form a light-screening film pattern. Hence, it follows that the dimensional variations of the light-screening film pattern finally formed include, in addition to the precision of the pattern of electron beams irradiated from an EB exposure apparatus, an error occurring when the pattern of electron beams is converted into the EB resist pattern, and a difference in pattern conversion produced when the light-screening film is etched using the EB resist pattern as an etching mask.
Since, however, the pattern-generating precision of the EB exposure apparatus is about .+-.0.1 .mu.m at present, it is necessary to keep the pattern-generating precision of the EB exposure apparatus and also make virtually zero the error factors that affect other dimensions and positional precision, in order to achieve the tolerable error .+-.0.08 calculated above. This fact shows that reticles necessary to form pattern dimension of 0.5 .mu.m or less on a wafer can be prepared with great difficulty when a conventional reticle preparation process is used. Hence, in order to establish the formation of fine patterns in a dimension of 0.5 .mu.m or less as a mass production technique in future, it is prerequisite to establish the technique for preparing high-precision reticles.
As the photomasks, those provided with a light-screening film pattern comprising chromium or the like, formed on a transparent substrate, have been hitherto used. However, as LSIs are made to have higher integration and patterns formed on wafers are made finer, it has been attempted to change the construction of photomasks so that the result of transferred pattern can be more improved, and there is a proposal of a technique called a phase-shift mask.
The phase-shift mask is a mask on the surface of which a pattern comprising what is called a phase shifter is formed in addition to a pattern comprising conventional light-screening film regions and light-transmitting regions. The phase shifter has a function to cause changes in the phases of transmitted light, where the positional relationship between the phase of this phase shifter and the light-screening film pattern and light-transmitting regions may be appropriately designed to form a mask. This makes it possible to obtain phase-shift masks with a higher resolution limit than conventional masks even when a projection lens of the same kind is used.
Thus, in the phase-shift mask, different from conventional photomasks, a light-screening film pattern and a phase shifter pattern must be formed on the photomask substrate. In addition, in order to obtain highly precise transfer patterns, both the light-screening film pattern and the phase shifter pattern must be formed faithfully to the designed size. Moreover, the overlap of the light-screening film pattern and the phase shifter pattern must be precise, and hence its preparation process becomes more complicated than that for conventional photomasks and various technical breakthroughs are needed.
The technical breakthroughs leading to a solution include, for one thing, a method of forming a phase shifter pattern. In a conventional photomask preparation process, the electron beam lithography is used to draw a pattern on an electron beam resist film by means of an electron beam exposure apparatus, followed by development to form a resist pattern, and a light-screening film is etched using this resist pattern as an etching mask of light-screening film. A light-screening film pattern is thus formed.
Hence, it is also possible to similarly use the conventional electron beam lithography in the formation of phase shifter patterns. However, an actual attempt to form phase shifter patterns according to the conventional process has revealed that there are the following two main problems.
One of them is the deterioration of mask surfaces that occurs when phase shifter patterns are formed by etching, and the other is a poor dimensional precision of phase shifter patterns that results when phase shifter patterns are formed by etching using an electron beam resist pattern as an etching mask.
It is difficult to avoid these two problems so long as dry etching such as reactive ion etching, capable of achieving anisotropic etching, is used as an etching process. Accordingly, it has been sought to establish a method by which phase shifter patterns can be formed without causing the deterioration of mask surfaces and also with high precision.

Pattern forming method by imparting hydrogen atoms and selectively depositing metal film


A method for forming an insulation film on a semiconductor substrate by plasma reaction includes: introducing into a reaction chamber a source gas of a silicon-containing hydrocarbon compound comprising in its molecule at least one Si—O bond and at least one bond selected from the group consisting of a Si—Si bond, Si—N bond, and Si—H bond; introducing into the reaction chamber an additive gas constituted by C, H, and optionally O; controlling a susceptor at a temperature of −50° C. to 50° C.; forming by plasma reaction an insulation film constituted by Si, O, H, and optionally N on an irregular surface of a substrate at a deposition rate of 100 nm/min or less; and heat-treating the substrate with the insulation film, thereby increasing a density of the insulation film to more than 2.1 g/cm3 as a result of the heat treatment.

1. Field of the Invention
This invention relates generally to a semiconductor technique and more particularly to a silicone polymer film or oxide film used as an insulation film on a semiconductor substrate, which is formed by using plasma CVD (chemical vapor deposition).
2. Description of the Related Art
In the plasma chemical vapor deposition method (plasma CVD method), deposition of a film on semiconductor substrates is conducted by placing each semiconductor substrate, being a processing target, on a resistance-heating type heater preheated to 0 to 350° C. in an atmosphere of 1 to 10 Torr. This heater is placed in a manner facing a shower plate that releases reactant gas, and high-frequency power of 13.56 MHz to 60 MHz, etc., is applied by 100 to 4,000 W to the shower plate to cause high-frequency discharge between the heater and shower plate and thereby generate plasma. The plasma CVD method is used to deposit various types of thin film, such as an interconnect insulation film, passivation film, and anti-reflection film. Since achieving a disproportionately high level of surface diffusion is difficult with parallel-plate type plasma CVD, high-density plasma CVD that uses microwaves has traditionally been used to form an oxide film, etc., having filling characteristics. These techniques have been used since the days of 250-nm device nodes. One feature of such apparatus is that it not only forms a film, but also performs etching of a film, which means that the apparatus can support smaller hole diameters. With current products having device nodes of 65 nm to 90 nm, the mainstream processing method is one that combines film formation and etch-back. Representative processes in which this method is used include STI (Shallow Trench Isolation), and upper-layer processing in the wiring process.
However, combination of film formation and etch-back will not likely support smaller device nodes of 60 nm and below, and there is a need for an insulation film offering sufficient filling characteristics in line with the accelerating trend for super-fine circuitry.

Method for forming insulation film having high density


A method of making a patterned OLED layer or layers. The method uses a shadow mask having, for example, a free-standing silicon nitride membrane to pattern color emitter material with a feature size of less than 10 microns. The methods can be used, for example, in the manufacture of OLED microdisplays.

The OLED diode structure was discovered in 1987, and has been developed into a technology that is used for displays in cellphones, microdisplays and televisions. Microdisplays are small displays that are used under magnification or for projection applications. Some of the applications of microdisplays are camera viewfinders and wearable displays, specifically for professions that require hands free information or for virtual reality applications. Google Glass, currently in development, could usher in mass market microdisplays.
One feature that differentiates microdisplays from normal displays is that the pixel density of microdisplays is much greater than normal displays. An example of normal displays with high pixel densities are the displays on the Samsung Galaxy S4 and the HTC One with 441 and 468 pixels per inch (PPI), respectively. Pixel densities on some microdisplays such as eMagin SXGA and Holoeye HED 6001 have 2646 and 3175 PPI, respectively, about an order of magnitude higher in PPI than normal displays.
Most microdisplays are fabricated on single crystal silicon substrates using CMOS technology. For most microdisplays, liquid crystals (LC) with backlighting are used, but a growing segment of microdisplays are based on organic light emitting diodes (OLEDs). OLED microdisplays have a few advantages over LC microdisplays: OLED is intrinsically simpler in design, does not need backlighting, has a higher viewing angle, faster response time, higher contrast, and it has a higher temperature operating range.
A full color (i.e. RGB colors) OLED display requires patterning to place individual color OLED stacks onto its respective color sub-pixels. Conventional patterning using lithography is not possible with organics due to the sensitivity of the organics to photoresist and chemistries, which is required for photoresist processing. There are few methods to pattern organics other than photoresist such as metal shadow mask, organic vapor jet deposition, and thermal dye transfer. All commercial high resolution full color OLED displays are made using shadow mask patterning in which fine metal masks (FMM) are used.
Current methods produce color emitter layers with a metal shadow mask, which suffers from resolution issues and may prevent color emitter sub-pixel sizes under 10 μm. Other methods create high-resolution OLED microdisplay RGB sub-pixels using a white OLED overlaid with a color filter. The color filters may absorb approximately 80% of the white light and reduce light output from the OLED.


A golf ball 2 includes a core 4, a mid layer 6, and a cover 8. The core 4 includes a center 10 and an envelope layer 12. The ratio of the volume Ve of the core 4 to the volume of a phantom sphere of the golf ball 2 is equal to greater than 76%. The ratio (Co/Ce) of an amount of compressive deformation Co of the center 10 to an amount of compressive deformation Ce of the core 4 is greater than 2.0 but less than 3.0. The ratio (Vo/Ve) of the volume Vo of the center 10 to the volume Ve of the core 4 is equal to or greater than 0.01 but equal to or less than 0.13.

1. Field of the Invention
The present invention relates to golf balls. Specifically, the present invention relates to multi-piece golf balls that include a center, an envelope layer, a mid layer, and a cover.
2. Description of the Related Art
Golf players' foremost requirement for golf balls is flight performance. Golf players place importance on flight performance upon shots with a driver and a long iron. Flight performance correlates with the resilience performance of a golf ball. When a golf ball with excellent resilience performance is hit, the golf ball flies at a high speed, thereby achieving a large flight distance.
An appropriate trajectory height is required in order to achieve a large flight distance. A trajectory height depends on a spin rate and a launch angle. In a golf ball that achieves a high trajectory by a high spin rate, a flight distance is insufficient. In a golf ball that achieves a high trajectory by a high launch angle, a large flight distance is obtained. Use of a core having an outer-hard/inner-soft structure can achieve a low spin rate and a high launch angle.
In light of achieving various performance characteristics, golf balls each having a multilayer structure have been proposed. JPH9-56848 (U.S. Pat. No. 5,725,442) discloses a golf ball that includes a core, an inner cover, and an outer cover. The core consists of an inner sphere and an envelope layer.
JPH10-328326 (U.S. Pat. No. 6,468,169) discloses a golf ball that includes a core, an envelope layer, an inner cover, and an outer cover.
JP2001-17575 (U.S. Pat. No. 6,271,296) discloses a golf ball that includes a core, an envelope layer, a mid layer, and a cover.
JP2002-272880 (U.S. Pat. No. 6,913,547) discloses a golf ball that includes a core and a cover. The core consists of a center and an outer core layer. The cover consists of an inner cover layer and an outer cover layer.
JP2003-205052 (US 2003/0166422) discloses a golf ball that includes a center, a mid layer, and a cover.
JP2004-130072 (US 2004/0029648) discloses a golf ball that includes a core and a cover. The core has a three-layer structure.
JP2006-289065 (US 2006/0229143 and US 2007/0155541) discloses a golf ball that includes a core and a cover. The core consists of an inner layer and an outer layer.
A shot with a middle iron is mainly intended to carry a golf ball onto a putting green. Even for a shot with a middle iron, a golf ball having a large flight distance is advantageous similarly to shots with a driver and a long iron.
The loft angle of a middle iron is greater than that of a long iron. Upon a shot with a middle iron, the spin rate is high as compared to that upon a shot with a long iron. The trajectory upon a shot with a middle iron is high. The trajectory upon a shot with a middle iron is likely to be influenced by wind. In particular, when a headwind blows, a flight distance is considerably impaired. A golf ball that is unlikely to be influenced by wind upon a shot with a middle iron is desired.
Golf players also place importance on spin performance of golf balls. When a backspin rate is high, the run is short. It is easy for golf players to cause a golf ball, to which backspin is easily provided, to stop at a target point. When a sidespin rate is high, the golf ball tends to curve. It is easy for golf players to intentionally cause a golf ball, to which sidespin is easily provided, to curve. A golf ball to which spin is easily provided has excellent controllability. In particular, advanced golf players place importance on controllability upon a shot with a short iron.
An object of the present invention is to provide a golf ball having excellent flight performance when being hit with a middle iron. Another object of the present invention is to provide a golf ball having excellent controllability when being hit with a short iron.

This patent is subject to a terminal disclaimer.


A level restore circuit used in MOS logic circuit design provides a voltage swing from a valid low to a valid high logic level in response to an input signal ranging from a degraded voltage high signal to a logic low signal. An input stage receives the degraded logic signal and provides separate gate drive signals to an inverter. An inverter in the intermediate stage receives the separate drive signals and provides an inverted signal output at a valid logic level. The intermediate stage also includes a pull-up device to pull up one of the gate nodes of the inverter to a logic high level. An output stage can optionally be coupled to the inverter to isolate it from a load.

In logic circuit design, it is sometimes necessary to insert level restoration circuitry into a circuit to restore a signal to a valid logic level. For example, a very long routing path in an integrated circuit can degrade a high logic signal due to the impedance of the routing trace. Heavily loaded lines can also degrade a valid logic high signal. This problem also occurs in pass-gate logic designs that include a number of transistors coupled in series because of the threshold voltage drop across the transistors.
Serial pass-gate logic refers to logic circuits where logical functions are implemented using a network of pass-gates coupled in series. FIG. 1 is a schematic diagram illustrating an example of a pass-gate string 20 coupled to an inverter 22. The term, "pass-gate" refers to the manner in which a gate in the logic network passes a logic signal from an input to an output when the gate is turned on. For example, FIG. 1 illustrates a string of four pass-gates 24-30 coupled in series. In order for the logic signal to pass from the input of the first pass-gate 24 to the output of the fourth pass-gate 30, each of the four pass-gates must be turned on.
Logic functions may be constructed from a network of pass-gates to produce a desired output in response to one or more inputs. When pass-gates are constructed of N-channel transistors coupled in series, it is sometimes difficult to produce valid logic signals at the output of the pass-gate network. Consider, for example, the pass-gate network illustrated in FIG. 1. This particular pass-gate network is able to produce a valid logic zero level, but it cannot produce a valid logic one level. The signal level is degraded because of the threshold voltage drop across each of the four pass-gates 24-30 coupled in series. Assuming a threshold voltage drop of one volt across the pass-gate string 20 and a supply voltage of 3 volts, the output of the N-channel pass-gate string will swing from about zero volts to about 2 volts. This output voltage swing is insufficient to reliably drive other logic stages coupled to the output of the pass-gate network.
Specifically in this case, the voltage swing produced by the pass-gate string is insufficient to reliably drive the inverter 22 coupled to the output of the pass-gate network. As a result, the P-channel transistor 32 in the inverter does not completely turn off when the logic signal at 2 volts is applied to the input. The failure of the P-channel transistor 32 to turn off can cause excessive static current to flow through the inverter and attenuate its output swing.
One possible solution is to increase the supply voltage. However, this alternative is unsatisfactory because the trend in the industry is toward lower power devices that operate at lower supply voltages. Increasing the supply voltage is contrary to this trend and results in higher power consumption.
Another possible solution is to use a pull-up transistor connected as shown in FIG. 2. FIG. 2 is a schematic diagram of an N-channel pass-gate network 40 with a P-channel pull-up transistor 42. In this example, the P-channel pull-up transistor 42 is added to address the insufficient gate drive problem. The P-channel pull-up transistor 42 is driven by the output 44 of the inverter 46 and is designed to pull-up the output of the pass-gate network 40 to a valid logic signal. The P-channel transistor 42 coupled to the output of the inverter 46 forms a feedback path that detects the N-channel transistor 48 in the inverter turning on, and in response ensures that the P-channel transistor 50 in the inverter turns off.
When used in conjunction with an N-channel pass-gate network as shown in FIG. 2, the pull-up transistor 42 addresses the gate drive problem sufficiently at low frequencies. However, as the frequency increases, the P-channel pull-up transistor 42 cannot turn on fast enough to pull-up the output of the pass-gate network 40 to a valid logic signal. As a result, the signal swing at the input of the inverter 46 decreases, and eventually reaches an insufficient voltage swing from zero to 2 volts.
When a small pull-up transistor is used is relative to the N-channel devices in the pass-gate string, the source impedance of the pull-up transistor 42 is higher. As such, the pull-up transistor 42 cannot provide sufficient current to pull-up the transistors in the pass-gate string 40. The larger N-channel devices have a higher parasitic capacitance relative to the pull-up transistor, and thus, are more difficult to pull-up to a logic high level.
One solution to this problem is to increase the size of the pull-up transistor. This is an unsatisfactory solution, however, because it causes the logic level zero signal to the inverter to be degraded. The pass-gate string 40, due to its high resistance value, cannot source zero volts while the pull-up transistor 42 is active. The pass-gate string current must overcome the current sourced by the pull-up transistor 42 to achieve a logic zero value.
The problem with the pull-up transistor 42 in FIG. 2 is especially a concern when the speed of the N-channel and P-channel transistors is not matched. When the P-channel is faster than the N-channel devices in the string, it is more difficult for the N-channel devices to provide a valid logic low. In this case, the impedance of the pass-gate string is higher, making it more difficult for the string to sink current. When the N-channel devices are faster than the P-channel devices, it is more difficult for the P-channel device to source current and pull-up the output of the string to a logic high level.
As is apparent from the foregoing discussion, there is a need for an improved restoration circuit for insuring valid logic signals in pass-gate networks.

Level restoration circuit for pass logic devices


An air cleaner for a vehicle has an improved door locking structure that is not affected by the temperature of an engine compartment, and is configured to performing a door opening/closing operation and a filter replacing operation by simple manipulation. The air cleaner includes: a filter assembly; a case accommodating and providing access to the filter assembly; a door rotatably installed at the case that opens and closes the entrance of the case; an elastic member mounted between the door and the case to apply an elastic restoring force; and a locking unit installed that locks the door at a closed position and unlocks the door by one touch manipulation of pressing the door at the closed position.

1. Field of Invention
The present invention relates to an air cleaner for a vehicle, and more particularly, to an air cleaner for a vehicle having an improved door locking structure not affected by the temperature of an engine compartment and the air cleaner configured to be capable of performing a door opening/closing operation and a filter replacing operation by simple manipulation.
2. Description of Related Art
In general, intake systems for engines are systems that supply air required in a combustion process to an engine. An intake system for an engine includes an air cleaner that removes foreign substances in the air inhaled into the engine.
Since dust contained in the air or a fine impurity is included in the inhaled air, the inhaled air, dust or impurity of which is removed, must be supplied to a cylinder of the engine.
Thus, an air cleaner that purifies the inhaled air required for the combustion process of the engine is mounted on the intake system for the engine. The air cleaner is fixedly disposed in the intake system for the engine in a state in which a filter element of the air cleaner is hung or inserted between an upper case and a lower case.
Thus, the inhaled air introduced into a case through a duct passes through the filter element inside the air cleaner and then is supplied to the engine via an air hose. Thus, the inhaled air, foreign substances of which are removed by the filter element, is supplied to the cylinder such that the engine shows a high output and abrasion of the engine is prevented.
The filter element of the air cleaner needs to be periodically cleaned or replaced. Thus, an air cleaner that is capable of easily removing and mounting the filter element is required. A drawer type structure, in which the filter element can be inserted/removed into/from an inside of the case in a slide manner, has been proposed.
Prior-art documents 1 and 2 disclose constructions in which a filter element of an air cleaner can be inserted/removed into/from an inside of a case simply in a drawer manner without disassembling the case so that an operation of replacing the filter element can be easily performed.
However, air cleaners disclosed in prior-art documents 1 and 2 use additional frames (prior-art document 1: a frame at which a handle is installed, prior-art document 2: a drawer type case) having drawer shapes for fixing the filter element, and require a fixing unit for fixing the frame on which the filter element is mounted, to the case (upper/lower housing or case).
Since the air cleaners disclosed in prior-art documents 1 and 2 each have a structure using the frame, the number of operations when the filter element is replaced with a new one is large. That is, the frame must be taken out from the case and then the filter element must be removed from the frame, a new filter element must be mounted on the frame again and then, the frame must be inserted into the case.
In this procedure, the air cleaner disclosed in prior-art document 2 further requires a cumbersome procedure of releasing a fixed state of a ring-shaped holder that is a fixing unit, replacing the holder with a new one and then fixing the new holder again.
Furthermore, since directivity in which the filter element must be mounted in a predetermined direction, exists in a direction in which the filter element is to be mounted, convenience in the replacing operation is lowered.
Prior-art document 3 discloses an air cleaner having a frame structure using a link unit in which an operation of replacing a filter assembly including a filter element can be easily performed. The air cleaner disclosed in prior-art document 3 includes a door that opens/closes an entrance of a case and the link unit that causes the filter element to closely contact the case or to release the close-contact state of the filter assembly while being interlocked with a rotation operation of the door.
A hook-shaped clamp is formed integrally with the door so as to maintain a closed state. The clamp is fastened to a hanging jaw of an upper case and thus the door can be maintained in the closed state.
A coupling protrusion that protrudes laterally and a gasket (rubber seal) that is formed of a rubber material and is long installed to surround the coupling protrusion are provided at an outer side of the frame of the filter assembly. The gasket closely contacts an inner side of the case and a horizontal link so that airtightness can be maintained.
In the air cleaner disclosed in prior-art document 3, when the door is opened, a state in which the filter assembly closely contacts the case, is released, and the filter assembly can be easily removed from the case in the slide manner. Subsequently, when a new filter assembly is accommodated in the case and is coupled to the link unit and then the door is closed, the filter assembly is automatically in close contact with the case and is fixed thereto.
However, in the above-mentioned air cleaners, when the temperature of the engine rises, the clamp formed of a plastic material expands by heat such that a coupling force to the hanging jaw may be lowered. As a result, the fixed state of the filter assembly is released when the door is opened due to vibration.
A process of opening the door by releasing the hung state of the clamp is inconvenient (the number of processes is large), the coupling protrusion and the gasket have a complicated coupling structure, and friction between the gasket (that is long installed in all sections of the coupling protrusion in a lengthwise direction), the inner side of the case and the link is large such that the door and the link are not easily moved when the door is opened (there is a sense of tightness).
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.


A system and method for controlling multiple cooling fans is presented. The circuitry for directly driving each of the motors is removed from the motor casings, thus increasing air flow and reducing replacement costs should a motor fail. The system includes a common processor for centrally controlling the speeds of the motors and monitoring the performance of each of the multiple motors.

The present invention relates to the control of DC motors. In particular, the present invention relates to a system and method for controlling multiple DC motors driving cooling fans.
Much electronic equipment is cooled by fans to remove heat generated by the operation of the equipment. Typically, the fans are incorporated into the chassis (referred to as a fan bank, fan panel, etc.), frame, or cabinet housing the equipment and force air through the cabinet to cool the components contained therein. For equipment that generates a lot of heat, multiple fans are used, and may be switched on or off in response to temperatures inside the frame. It is not uncommon to find a bank of six to eight fans cooling a frame. Each fan may be independently controlled by an associated temperature sensor, or a single temperature sensor may control all fans in the bank simultaneously.
Another arrangement of fan control is to vary the speed of the fans in response to the temperature sensor. Drive circuitry for variable speed fan motors, however, is typically bulky and itself generates heat that has to be removed from the frame by the airflow. Because the direct current ("DC") motors may draw substantial currents, the drive circuitry typically include, among other electronic components, a large power transistor and an associated heat sink, and a diode.
In conventional fan configurations, the drive circuitry and heat sink for the fan are mounted to the motor hub which tends to impede the airflow through the fan. For efficient airflow, the drive circuitry is required to occupy as small a volume in the hub as possible. This in turn limits the maximum power rating of the drive circuit transistors that can be used, thus limiting the power of the DC motor resulting in low efficiency airflow. For example, for 40 mm and 80 mm motors used in typical cooling fans, about a third of the volume of the motor hub is occupied by drive circuit electronics. In the prior art there are, therefore, limiting factors in the performance of the fan due to the volume occupied by the drive circuitry. An especially critical application, for example, is in rack-mounted systems such as server farms, network switches, etc., where each piece of rack-mounted equipment is restricted in height affording very little room for proper airflow.
One industry standard defines a unit of measure, called a "rack unit," for a piece of equipment as being ˜44 mm (1.75 inches) in height; referred to as 1 U. The equipment can be integral multiples of 1 U in height, referred to as 2 U components, and so on. In typical rack-mounted systems, the height of the rack can be 42 U, meaning there can be 42 pieces equipment, 1 U tall, mounted into that rack. Heat generation and removal are a significant concern in such densely populated racks.
Another consideration when the drive circuitry is mounted on the motor hub is the cost of replacing a failed motor. As is known in the art, the motor may fail due to overheating of the windings or a mechanical breakdown, e.g., a damaged ball bearing assembly retaining the spindle of the motor. Because the drive circuitry is mounted on the motor hub, it is replaced along with the failed motor. Typically, the most expensive part of the fan is a microcontroller integrated circuit in the drive circuit and not the DC motor itself. Therefore, also taking the other electronic components in the drive circuit into consideration, it is much more costly to replace the motor hub assembly than it is to replace only the DC motor component.
Further, in the prior art, each of the fans operates independently of the other fans and sets its own rotational speed. There is no coordinated control of the set of fans in order to stabilize the airflow through the frame. The feedback that is established between the motor speeds and the reactions of the temperature sensor to the varying airflow caused by the independent motor speeds is not as predictable as a stable airflow caused by coordinated motor speeds.

System and method for controlling multiple DC fans


A technique for assaying samples entails irradiating a sample with a beam of gamma rays of sufficient energy to excite the nuclei of the assay elements into their isomeric states, ceasing the irradiation, detecting the gamma rays resulting from the decay of the isomeric states to the ground state, and analyzing the detected gamma rays to determine the content of assay elements in the sample. In a preferred embodiment, the apparatus is configured such that the irradiated sample is rapidly moved to a shielded environment in which the gamma rays from the isomeric transitions are detected. The system is ideally suited for analyzing large samples of ore for gold, silver, barium and other assay elements, but can be embodied to detect any assay elements susceptible to photon activation analysis in any sample geometry.

Classical fire assaying is and has remained the standard assay for gold and silver in precious metal mining. In this technique, a small rock sample, typically 30-150 grams (gm) is mixed with litharge (lead oxide) and silica fluxes and fused in a high temperature furnace. A resultant lead button containing solubilized gold and silver is poured into a conical mold. This lead button is subsequently cupeled in a bone ash or other cupel whereby the molten lead is converted to lead oxide which is absorbed by the substance of the cupel. When the cupeling is completed, a small dore bead of gold and silver remains.
This bead is parted in nitric acid to remove the silver after recording the initial weight. The parted bead is weighed again giving the gold weight directly. The silver weight is found by difference of the dore bead weight and the gold bead weight. Alternatively, the dore bead can be dissolved in aqua regia and the resultant solution analyzed on an atomic absorption (A.A.) instrument. The original sample may also be digested in aqua regia to solubilize the gold and silver, and the resultant solution analyzed on an A.A. instrument. In this technique a small sample, typically 10 to 15 grams (gm), is digested in the aqua regia.
Some difficulty is encountered with samples that contain very low quantities of gold and silver. Several samples may be fused and the resultant beads added together to obtain greater sensitivity, but this required more time and extra cost. In addition, very great care is required in temperature control and timing to obtain accurate silver assays. While fire assaying is a very sensitive assay technique for gold particularly, which is why it has been used for such a long time, its sensitivity is limited by the size of bead that can be detected and weighed or solubilized in an A.A. finish. There are some organic solvents, such as M.T.B.K., which can extract gold from an aqueous solution and thus concentrate the gold for greater sensitivity on an A.A. instrument.
Additionally, all of these techniques suffer from allowing only small ore samples to be analyzed. In order for the sample data to be meaningful, the small sample must be representative of the larger and typically non homogeneous rock sample from which it is obtained. To date, the only technique which has allowed this representativeness has been a meticulous sample preparation wherein a large rock sample is crushed into successively smaller sizes before being split into a smaller sample. The final sample is pulverized typically to less than 150 mesh prior to be digested or fused for assay. This meticulous sample preparation is not only expensive, but it can be very difficult to achieve with native gold metallics present. Gold is usually not homogeneously distributed in a sample but occurs most commonly as metallics frequently alloyed with silver. While silver can occur as a native metallic, it is more frequently present with gold as electrum or combined with sulfur as a silver sulfide.
The problems are aggravated when the ore deposits are of low grade. The current price of gold and the development of process and mining technology has allowed the development of large low grade deposits. These deposits typically require much drilling and blasting to break the ore for processing. Large volumes of samples are prepared from these blast holes for assaying to control the mining.
The fire assay technique has remained the standard, and low throughput, low sensitivity for low gold content, and the requirement for meticulous sample preparation have been accepted as inevitable.
In view of the above discussion, and object of the present invention is to provide a system which can assay relatively large samples of ore for gold and other assay elements of interest.
An additional object of the invention is to provide an assay system for certain elements in various environments which requires minimal sample preparation.
Yet another object of the invention is to provide an assay system with throughput which is greater than the prior art fire assay method.
Another object of the invention is to provide an assay system with sensitivity sufficient to meet requirements for commercial ore testing and production standards.
Still another object of the invention is to provide an assay system whose accuracy and precision is not adversely affected by typically non homogeneous ore samples and especially relatively large, non homogeneous samples.
Another object of the invention is to provide an assay system that is relatively insensitive to sample geometry.
Yet another object of the invention is to provide a non destructive assay or analysis system that can be used with a wide variety of sample types to determine the elemental concentration of any element susceptible to detection by means of photon activation.
There are other objects and applications of the invention which will become apparent in the following disclosure.

Method and systems for gold assay in large ore samples


Disclosed is a novel monomer composition and its preparation that is useful in the production of polyesters. This novel monomer composition is 1-acetoacetamido-2,3-propane diol and can be used in the preparation of polyesters in combination with a dicarboxylic acid.

Polyesters of many different types have been used for many years in various applications such as molded articles, fibers, and films. Polyesters that are useful in industrial applications have a wide variety of properties but not all polyesters can be used in all applications. Each new polyester is useful for at least one application and then, if its cost is low, it is substituted for existing polyesters in that application. Some new polyesters have such unusual properties that their existence creates a useful application.
U.S. Pat. No. 4,263,364 discloses polyesters of polyethylene terephthalate and polyesters of terephthalic acid, 1,4-cyclohexanedimethanol and ethylene glycol. These polyesters have excellent impact strength.
U.S. Pat. Nos. 5,037,946, 5,057,595, and 5,011,877 disclose polyesters having high tensile strength.
U.S. Pat. Nos. 5,003,041 and 5,221,719 disclose polyester blends having good gas barrier properties.
U.S. Pat. No. 5,237,038 discloses polyesters having good properties such as good flexibility and high heat resistance.
U.S. Pat. Nos. 3,313,777, 3,772,405, 4,263,364 and 4,585,854 generally disclose polyesters that can contain 2,2,4,4-tetramethyl-1,3-cyclobutanediol and have various properties.
A particularly, useful class of polyesters for coatings applications are alkyd resins. Typically alkyd resins are low to moderate molecular weight polyesters which contain reactive functionality to permit crosslinking of the polyester into a high molecular weight film. Thus alkyd resins can be applied to a surface prior to the final crosslinking step. Examples of different alkyd resin systems are disclosed in U.S. Pat. Nos. 3,666,698, 3,699,066, 3,549,577 and 3,494,882.
Research is currently being conducted to develop new polyesters for new applications and new polyesters for existing applications that are less costly and/or have improved properties. This research is focused on combinations of existing monomers (combinations of glycols and polycarboxylic acids) and on the discovery of new monomers for incorporation into polyesters.
In light of the above, it would be very desirable to be able to produce a novel monomer in order to produce novel polyesters from the novel monomer in combinations with other monomers.
Of particular interest would be novel monomers which provide for new and low temperature means for crosslinking in alkyd resins.

1-acetoacetamido-2,3-propane diol monomer and polyesters prerpared therefrom


A solar cell has a photoelectric conversion semiconductor layer and an electrode made of a material containing a conductive base material and a resin binder electrically connected to the photoelectric conversion semiconductor layer, wherein the volume of voids in the electrode having a diameter of 0.1 .mu.m or greater is 0.04 ml/g or less.

1. Field of the Invention
The present invention relates to a solar cell for use as a power supply for a variety of electronic equipment or a power source for a power plant. More particularly, the invention relates to a solar cell having an improved electrode structure with excellent resistance to the environment. Also, it relates to a solar cell which has a cheap, flexible, and durable electrode grid.
2. Related Background Art
In recent years, there has been growing interest in the environment and energy sources because of global warming and radioactive pollution due to atomic power plant accidents. In view of these situations, solar cells have been expected to be exploited as a reproducible, inexhaustible source of clean energy. At present, three types of solar cells are well known: single crystal silicon, polycrystalline silicon, and amorphous silicon. The amorphous silicon type solar cell has excellent characteristics such as its thin film construction, which permits easy realization of large area cells, and a large light absorption coefficient, unlike the crystal type solar cells, even though it is inferior in conversion efficiency to the crystal type solar cell. Thus, the amorphous silicon type solar cell is one of the more promising types of solar cells. Since its cost is estimated to be significantly less than the crystal types if production reaches several hundreds of MW, many studies on it have been performed throughout the world. An example of a conventional amorphous silicon type solar cell is shown in FIG. 2. A photoelectric conversion semiconductor layer 103 made of amorphous silicon is formed on an electrically conductive substrate 104, and a transparent electrically conductive layer 102 also useful as an anti-reflection layer is formed thereon. On the transparent electrically conductive layer there is formed a grid electrode 101 as a current collector. If light 106 is incident on the photoelectric conversion layer 103 from the grid electrode 101, as shown in FIG. 2, light energy is converted into electric current within the conversion layer 103, and outputted through the transparent electrically conductive layer 102 via the grid electrode 101 and the electrically conductive substrate 104. The photoelectric conversion layer 103 contains at least one or more pin or pn junctions, with the p side acting as the anode and the n side as the cathode.
When the solar cell is used outdoors, particularly good characteristics with respect to environmental resistance are required. However, studies by the present inventor have revealed that in a conventional grid electrode, a short-circuit may take place between the electrodes of the solar cell due to water permeating voids in the electrode, which is one of the causes of a decrease in the conversion efficiency. For example, a conventional grid electrode is disclosed in Japanese Laid-Open Patent Application Nos. 59-167056, 59-167057, and 59-168669. Specifically, as described in Japanese Laid-Open Patent Application No. 59-167056, the grid electrode is constituted of a conductive paste composed of 80 wt % silver and 20 wt % phenolic resin binder, but it is poor in durability and the void volume (as shown at 105 in FIG. 2) may increase with time. With such an electrode, it is difficult to produce a solar cell having no degradation of conversion efficiency when exposed to the environment. This aspect will be described later in detail.
In general, a solar cell having an output of several W or greater is used outdoors. Therefore, so-called "environment proof" characteristics with respect to the temperature and humidity are required. Particularly in a solar cell having a grid electrode as a collector, a conductive material such as silver or the like contained in the grid electrode may dissolve by the permeation of water (as shown with Ag.sub.2 O in FIG. 3) and by the photoelectromotive force of the material, diffuse through defective portions such as pinholes or exfoliations. This causes a short-circuit between the positive and negative electrodes of the solar cell, thereby greatly decreasing the conversion efficiency. For example, when the conductive base material is silver, the reaction proceeds between the anode and the cathode according to the following formula, thereby giving rise to a short-circuit. EQU Anode Ag.sub.2 O and H.sub.2 O.fwdarw.2Ag.sup.+ +2OH.sup.- (A) EQU Cathode Ag.sup.+ +e.sup.- .fwdarw.Ag (dendritic crystal deposition)(B)
This behavior is shown in FIG. 3. A silver ion 305 arising from a positive-side collector electrode 101 enters a pinhole 306 existing in the photoelectric conversion semiconductor layer 103 due to an electric field produced by the absorption of light, and adheres to the conductive substrate 104 to form a dendritic type crystal 307. If the dendritic crystal grows, the collector electrode 101 of the solar cell is electrically shorted to the conductive substrate 104, so that the output of the solar cell is reduced. Consequently, degradation of the conversion efficiency may occur.


A LiDAR system includes a light source and an arrayed micro-optic configured to receive light from the light source so as to produce and project a two-dimensional array of light spots on a scene. The LiDAR system also includes receiver optics having an array of optical detection sites configured so as to be suitable for establishing a one-to-one correspondence between light spots in the two-dimensional array and optical detection sites in the receiver optics. The LiDAR system further includes a birefringent prism and a lens. The LiDAR system may also include a mask placed in the light path between the birefringent prism and the receiver optics. Alternatively, the LiDAR system may include a controller programmed to activate or deactivate each optical detection site.

Monostatic Light Detection and Ranging (LiDAR) systems have the advantage, over bistatic systems, of not being affected by parallax. However, this requires the transmitter and receiver to be at the same location or located along the same optical path. Physically, the transmitter and receiver cannot be placed in the same location. Other solutions (for photonic integrated circuit-based solid-state LiDAR or optical communications systems), such as using an integrated 3-dB splitter in a waveguide to provide separate paths for the outgoing signal and return signal can lead to crosstalk and additional return signal loss.

The Charles Stark Draper Laboratory, Inc.


Methods and systems according to one or more examples are provided for laminating composite materials. In one example, a method comprises receiving a first layer material and a second layer material at a nip roller assembly and laminating, by the nip roller assembly, the first and second layer material to provide a laminated composite material comprising a main portion and at least one edge portion. The method further comprises delaminating the at least one edge portion of the laminated composite material to provide a partially laminated composite material for use in manufacturing a composite product.

Various lamination processes are commonly used in the manufacture of composite materials. In this regard, heat or pressure may be applied to two or more layers which cause them to adhere, bind, or otherwise become fixed together. For example, in some cases, bonding agents or other materials provided between the layers may be activated by the applied heat or pressure to laminate the layers together.
In some conventional lamination processes, the edges of the resulting composite material may exhibit undesirable non-uniformities after passing through a nip roller assembly. Such non-uniformities may include, for example, curling of the edges, wrinkles, waves, inconsistent surface textures at the edges, and/or other inconsistencies.
Unfortunately, such edge non-uniformities can be problematic for downstream manufacturing processes. For example, certain processes may be preferably performed on a laminated composite material that is disposed in a substantially flat orientation. Non-uniformities in the edges of the laminated composite material may reduce the efficacy of such processes.
One conventional approach to solving these problems involves the use of nip rollers having a reduced width to avoid laminating the edges of the composite material. In this case, the nip rollers may be applied to a main portion of the layers, while the edges of the layers pass through unaffected. Unfortunately, this approach can be of only limited use as the costs and practical implementation of nip rollers generally require them to be maintained at a fixed size.
In another approach, it may be possible to discard the non-uniform edge portions of the laminated composite material, for example, by severing them from the main body of the laminated composite material. However, such an approach is also costly and results in wasted material.
Accordingly, there is a need for improved systems, apparatus, and related methods to reduce non-uniformities in the edges of laminated composite materials.


According to one embodiment, a display device includes a display panel including a first sub display area and a second sub display area, and an illumination device, wherein the illumination device includes a first light source opposed to the first sub display area, a second light source opposed to the second sub display area, and a partition positioned between the first and second light sources and the display panel, and the partition includes a first side surface surrounding the first light source, a second side surface surrounding the second light source, and a connector which connects the first side surface and the second side surface, and the connector is formed of curved surfaces, or two or more flat surfaces, or a combination of curved surfaces and flat surfaces.

As a kind of display devices, there is a commercially utilized structure including a liquid crystal display panel and a backlight with light sources disposed immediately below thereof. There is a proposed technique that, when adjacent light sources in a backlight are all turned on, the total strength of the light is made substantially even. Furthermore, there is another proposed technique that, when an image displayed in a head-up display, a range of the displayed image is recognized to turn on light sources corresponding to the range in order to reduce the power and to suppress heating. Furthermore, there is another proposed technique that a direct backlight has step pyramid holes in a holder tapered from the light emitting element side to the light emitting surface in order to reduce unevenness in the brightness. The direct backlight is also called straight fall type backlight.
When a light source array in which light sources are arranged at certain intervals is driven, it is required to reduce unevenness in the brightness caused by a dim line with low brightness and a bright line with high brightness. Furthermore, a display device including such an illumination device is required to suppress deterioration of display quality caused by such unevenness in the brightness of the illumination device.


Apparatus for skimming liquid from the surface of a body of liquid which includes a lighter liquid floating on a heavier liquid. The apparatus includes an upwardly opening container having a specific gravity which causes the container to float in the body of liquid with an upper edge of the container in the vicinity of the interface between the lighter and heavier liquids. An elongated suction tube has a lower end extending down into the container. The upper end of the suction tube is connected to a source of suction so liquid is withdrawn from the container through the tube.

This invention relates to apparatus for skimming liquid from the surface of a liquid body which includes two liquids of different densities.
The invention can be used to separate any mixture of liquids which separate under gravity, but it is especially useful in treating water covered by a layer of oil.
"Tramp" oils (hydraulic oils, lubricating oil for mills, lathes, and drill presses, transmission oil, and any other undesirable oil) are a source of many problems associated with wash water used in industrial parts washers, and with water-based coolants (which include a water-miscible organic lubricant) used in machining and grinding operations. The coolants are designed primarily to lubricate and cool the work and the cutting or grinding surfaces of the machine doing the work. The coolants reduce heat build-up during the machining or grinding process, and prevent the burning of parts, reduce distortion in the work piece, extend tool life, and permit faster production.
Machine coolants include oils, emulsifiers, and water-soluble oils to combine the lubrication property of cutting oils with the cooling ability and economy of water. The machine coolants are fairly expensive and, therefore, are recirculated for various machining operations. Wash water used in industrial parts washers is also recirculated to reduce costs. Coolants and wash water pick up various amounts of tramp oil during machining, grinding or washing operations.
Most coolant formulations absorb tramp oil if the two materials remain in intimate contact for a sufficient length of time. Absorbed tramp oil can change the desirable properties of the coolants, thereby negatively affecting tool life, surface finish of work pieces, and skin sensitivity of tool operators. Therefore, it is important to remove tramp oil from coolant formulations promptly and completely to minimize these adverse effects. Prompt and efficient separation of tramp oil from coolant also extends coolant life, improves machining, and minimizes maintenance. It is also important to separate tramp oil from wash water to minimize the amount of water which must be used, and thereby save storage and disposal costs.
A number of skimmers have been developed to separate oil and water mixtures, but most of these are expensive, inefficient or require a large amount of floor space. Previously available skimmers are also difficult to adjust and keep properly adjusted for efficient removal of the separated products for a variety of operating temperatures and materials.