Abstract: An etchant for semiconductors having a high preferential etch rate for doped silica particularly phosphorous doped silica, consisting of a 20:20:1 mixture, by volume, of 37% hydrochloric acid, deionized water, and 49% hydrofluoric acid. The etchant is particularly useful in a semiconductor process wherein an emitter opening is washed out following the diffusion thereof.

Abstract: Various devices are described herein utilizing anisotropic etching and dielectric isolations as means for limiting areas of either conductivity type semiconductor material. Surface junctions normally found in the diffused semiconductor devices of the prior art are also eliminated by the use of overlap diffusion techniques. Anisotropic etching is employed in certain of the devices for attaining buried PN junctions.

Abstract: Liquid crystal compositions consisting essentially of certain N-(p-alkyloxybenzylidene)-p-alkylanilines with certain p-alkoxyphenyl-p'-alkylbenzoates and/or p-alkylphenyl-p'-cyanobenzoates exhibit a glassy structure at low temperatures, rather than a solid crystal form. The compositions also have a broad operating temperature range, suitable for use in liquid crystal displays. Liquid crystal displays incorporating these compositions maintain high contrast when exposed to low temperatures, while conventional liquid crystal compositions lose high contrast when so exposed to low temperatures.

Abstract: Wire bonding is eliminated in the assembly of microelectronic devices, by a process involving the direct bonding of circuit electrodes to a metallic sheet-frame member having a plurality of inwardly extending leads. A single-step bonding technique is employed for the simultaneous bonding of all leads to a semiconductor integrated circuit chip. Lateral confinement of the lead frame member during the bonding steps causes a buckling action in the lead fingers, to introduce a small but critical loop in each lead to ensure clearance between the lead fingers and the perimeter of the semiconductor chip, whereby electrical shorting is avoided. The loop also provides a structural flexibility in the leads, which tends to protect the bonding sites from excessive stresses. Subsequently, the first frame member including the bonded circuit is attached, preferably by resistance welding, to a second lead frame member of heavier gage and increased dimensions, suitable for connection with external circuitry.

Abstract: A semiconductor device having metallization consisting essentially of beryllium. The beryllium makes ohmic contact by deposition on a substrate at 300.degree. C-400.degree. C or it is deposited at lower temperatures and then heat treated to render ohmic the contact to the semiconductor device.

Abstract: There is disclosed a method of manufacturing a multicolor monolithic light display utilizing the etching of multiple channels in a substrate and selectively refilling said channels with single crystal material, each channel being filled with material capable of emitting light of a given wavelength, depending on the dopant or the type of material deposited. There is also disclosed a multicolor or monolithic light display comprising at least a pair of matrices of light emitting diodes in an integral structure which pair of matrices are alternatively or simultaneously, scannable to produce a display in a first and a second color. Each matrix includes a plurality of light emitting diodes, preferably gallium phosphide, which, by proper doping, can be made to emit either a red or a green wavelength of light.

Abstract: A molding compound consisting essentially of 0.1 to 10 percent of N-methyl-2-pyrrolidone and a resin selected from the group consisting of epoxy, phenolic and silicone resins. The compound is injected in the mold as in the standard molding process and reacts with any surface contamination that may remain from the previous injection. The contamination is thereby removed with the removal of the molded device and the process is essentially self-cleaning.

Abstract: Machine readable identifying indices for a semiconductor wafer having a top surface, a bottom surface, and at least one flat edge is placed on the bottom surface of the semiconductor wafer, positioned in a predetermined relationship to the flat edge, desirably parallel to the flat edge. Means is provided for directing a first beam of radiant energy at the machine readable code and a second beam of radiant energy at the semiconductor wafer proximate to the machine readable code. Sensing means detects the first and second beams after impinging on the semiconductor wafer. A differential amplifier produces a series of output pulses representing the machine readable code. The output from the sensing means constitutes the inputs to the differential amplifier. In a preferred form, the machine readable code is a bar code including error check symbols. This approach gives a simplified means for identifying semiconductor wafers that is highly reliable.

Abstract: Immersion of semiconductor devices, particularly diodes, having a defective tin plating thereon in a solution of 5 - 20 percent by weight trichloroacetic acid, 0.1 to 5 percent by weight of a compound selected from the group consisting of cationic, anionic, and nonionic surfactants and the balance water effectively removes the tin therefrom. The process is effective at room temperature but preferably is performed at approximately 100.degree. C.

Abstract: Wire bonding is eliminated in the assembly of microelectronic devices, by a process involving the direct bonding of circuit electrodes to an unsupported metallic sheet-frame member having a plurality of inwardly extending leads. A single-step vibratory pressure welding technique is employed for the simultaneous bonding of all leads to a semiconductor integrated circuit chip. Lateral confinement of the leads during the bonding steps causes a buckling action to introduce a small but critical loop in each lead to ensure clearance between the lead fingers and the perimeter of the semiconductor chip, whereby electrical shorting is avoided. The loop also provides a structural flexibility in the leads, which tends to protect the bonding sites from excessive stresses. Subsequently, the first frame member including the bonded circuit is attached, preferably by resistance welding, to a second lead frame member of heavier gage and increased dimensions, suitable for connection with external circuitry.

Abstract: A method of producing monocrystalline semiconductor material in web form which provides the steps of providing a web of polycrystalline semiconductor material having a width which is much greater than its thickness, providing a monocrystalline semiconductor material seed having the same relative dimensions as the polycrystalline material source, providing one or more semiconductor material shaping members, contacting the source, the seed and the shaping member and heating the interface therebetween preferentially to produce a molten zone, moving said monocrystalline semiconductor material seed away from said molten zone as monocrystalline semiconductor material is formed thereon.

Abstract: A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.

Abstract: A metallization system for metallurgically bonding a semiconductor die to metallic conducting slugs as terminals at the same time, and at the same temperature, that a surrounding glass sleeve is hermetically sealed to the conducting slugs for forming a zener diode, for example, is disclosed. The metallization system comprises a combination of aluminum, tin and palladium, for bonding to molybdenum, the aluminum being vapor deposited followed by a vapor co-deposition of aluminum and tin and further followed by a vapor deposited layer of palladium.

Abstract: Apparatus utilizes two or more orifices in series, fixed normal to the flow field, which provide a pressure reservoir from which the static pressure is sensed for the purpose of sensing variations in flow within a tube. The apparatus comprises a plurality of orifices, flow regulators, pressure repeaters and electrical pressure switches all connected so as to function as a complete system.

Abstract: A composition for the corrosion protection of a metallized semiconductor die or wafer containing an alcohol solution of boron, phosphorous and a metal selected from the group consisting of gold, palladium, rhodium and platinum. The solution is prepared by mixing phosphorous pentoxide in an alcohol solvent. The dissolution of the phosphorous pentoxide is exothermic and the temperature of the solution will rise during the reaction. Then boric anhydride and a salt or oxide of gold, palladium, rhodium or platinum are added to the solution.

Abstract: Apparatus for automatically controlling, by stationary optical means, the diameter of a crystal from seed to final taper in a Czochralski crystal pulling method is disclosed. The diameter control has a feed back loop including diameter sensing means which controls a motor for moving the pulled crystal up faster or slower. The diameter, at any value, is sensed by two closely adjacent photocells receiving radiation from spaced points on the solid-liquid interface and a voltage value corresponding to that diameter is developed.When a constant diameter is being maintained and the diameter increases, the magnitudes of the sensed radiation change and a difference signal voltage in one direction is generated causing the crystal pull rate to increase. When the diameter decreases the magnitudes of the sensed radiation change in the reverse and a difference signal voltage in the opposite direction is generated causing crystal pull rate to decrease.

Abstract: In the manufacture of semiconductor components, more radiation tolerant semiconductors are accomplished by growing a uniform epitaxial collector region on a dielectrically isolated substrate having islands of high conductivity semiconductor material.

Abstract: A process for preparing an aluminum foil for coating with photoresist for the purpose of preparing an etched strip for semiconductor assembly utilizing the step of cleaning said aluminum surface with a water solution comprising one to five percent ammonium persulfate, one to five percent sodium chlorate and one to three percent of a surfactant selected from the group consisting of dioctyl sodium sulfo succinate and dodecyl benzene sulfonate.

Abstract: A method for fabricating a liquid crystal display device includes the steps of providing a pair of insulated electrode-carrying plates, depositing on the surface of one of the plates, overlying the electrodes a layer of photopolymeric material approximately 0.0005 inches in thickness, masking and light exposing the photopolymeric layer and thereafter developing a way with a suitable solvent a predetermined area of material to provide a cavity in the photopolymeric layer through which the electrodes on the plate are accessible. On the surface of the second one of the plates whereat the second set of electrodes are located, a layer of photopolymeric material of approximately 0.

Abstract: A monolithic two-phase charge coupled MNOS device having on a substrate an oxide layer having alternate relatively thin and thick regions thereof and a nitride layer thereon. Alternate electrodes for distributing, respectively, first and second phase clock signals are provided on the nitride layer. Each electrode overlays both a thin region and an adjacent thick region in the oxide layer. The MNOS devices formed by an electrode, the nitride layer, a thin oxide region in the oxide layer, and the substrate have electrically alterable threshold voltages, which permits electrical alteration of the surface potential pattern, so that the direction of transfer of a charge packet during the shifting operation may be electrically predetermined.