Abstract: A semiconductor device for flush mounting to an external heatsink includes an integral encapsulating body and an internal heatsink having a surface for heat transfer to an external heatsink. The encapsulating body encloses a semiconductor element and a portion of the internal heatsink but has a lower surface which when mounted to the external heatsink, lies above the surface thereof thereby insuring that flush mounting can be consistently achieved.

Abstract: A light-control device includes a liquid crystal material sandwiched between a pair of planar, light-transmitting members. The liquid crystal material particularly includes an asymmetrical azine compound having the general formula: ##STR1## wherein R.sub.1 and R.sub.2 are different para-substituents selected from the group comprising cyano, halogen, alkyl, and substituted alkyl radicals in which the alkyl radical has from one to nine carbon atoms, and wherein X and Y are selected from the group comprising hydrogen and methyl radicals.

Abstract: A semiconductor device is described wherein a semiconductor pellet is disposed within a hermetically sealed chamber including a thermally conductive base and a substantially rigid housing, said housing including an open upper chamber in which are disposed electrical terminals and which is filled with a sealing and strengthening layer to substantially increase the strength and hermeticity of the package.

Abstract: A method for forming an electrode on a semiconductor device is described. Where surface adjacent regions of differing dislocation densities are present, an initial mechanical abrading step followed by a plasma etching step produces a surface to which a metal layer may be applied with relatively uniform adherence characteristics.

Abstract: A p-type region is formed in a semiconductor body by diffusion of aluminum from an aluminum oxide source in an open tube process. Both ceramic aluminum oxide and sapphire sources are described and an inert atmosphere of argon and hydrogen provides stable results. An alternative embodiment provides both the deep diffusion characteristics of aluminum with the high surface concentration of boron by using a boron nitride wafer carrier.

Abstract: A method for forming a p-conductivity type layer in a semiconductor wafer using aluminum as a diffusion source and which can be carried out in an open diffusion tube is described. A variety of aluminum sources can be employed in an open tube. A stream of essentially oxygen-free inert gas provides transport for the dopant and prevents the entry of potentially contaminating ambient into the tube.

Abstract: The valve adjustment tool includes an elongated barrel having a bore therethrough. The upper portion of the barrel is provided with a tool land and a length of external threads. The lower end of the barrel is provided with an integral collet which forms a nut socket. The collet is surrounded by a compression collar. An elongated internally threaded sleeve overlays the barrel. The sleeve abuts the compression collar. When the sleeve is threaded downwardly on the barrel, the collar compresses the collet. When the sleeve is threaded upwardly on the barrel, the collar is free to move and the collet assumes its uncompressed state. An elongated valve adjuster driver is also provided. The driver is provided with a large disc shaped knob at its upper end and an engagement lug at its lower end. The driver normally reposes within the through-bore of the barrel and is rotatable therein and removable therefrom. The top of the disc shaped knob provides a landing for the foot of a dial indicator.

Abstract: An improved unijunction transistor having increased valley current is characterized by a region of locally lower lifetime proximate the emitter-base junction. The lifetime is reduced either by overall irradiation of the device or, more preferably, by selective irradiation of the junction area alone.

Abstract: Apparatus for dispensing flowable particulate materials from a storage container while protecting the material from unnecessary exposure to ambient atmosphere through a double vapor control mechanism. The apparatus includes a funnel unit mounted below the container for receipt of particulate material therefrom. A flow control disc is mounted between the container and the funnel unit to control the flow of material into the funnel unit, irrespective of the head of material within the funnel. A hollow, moveable, metering bell, and moveable funnel outlet closure are mounted on a common reciprocable rod within the funnel and are normally seated between cycles to provide double isolation of the material from the ambient atmosphere.

Abstract: A carriage reciprocator and positioner is provided with two air clutches and a continuously moving chain. The chain is arranged to move over co-planar spaced sprockets so as to present one direction of chain motion to the top of the carriage and a second direction of chain motion to the bottom of the carriage. The carriage is also provided with two chain engaging sprockets each controlled by a respective one of two air clutches. The chain engaging sprockets on the carriage normally idle with chain motion. However actuation of the controlling air clutch halts the spinning and forces the sprocket and clutch to act as a unit to thereby move the carriage linearly along the length of the chain in a direction dependent upon which portion of the chain was so engaged. Means are provided to automatically reverse the stroke, to vary the length of the stroke and to vary the speed of the stroke.

Abstract: A bilateral optically coupled phototransistor includes an infrared emitting diode coupled with a light sensitive transistor. The transistor includes symmetrical interdigitated emitter and collector regions separated by a light sensitive base. Diffused, epitaxial and thermal gradient migration structures are described. Applications are illustrated for variable resistor and analog switch modes of operation.

Abstract: An electronic circuit which tracks an electrical signal to determine if the slope of the signal equals or exceeds a predetermined value in a predetermined time.

Abstract: A light-control device includes a liquid crystal material sandwiched between a pair of planar, light-transmitting members. The liquid crystal material particularly includes an asymmetrical azine compound having the general formula: ##STR1## wherein R.sub.1 and R.sub.2 are different para-substituents selected from the group comprising cyano, halogen, alkyl, and substituted alkyl radicals in which the alkyl radical has from one to nine carbon atoms, and wherein X and Y are selected from the group comprising hydrogen and methyl radicals.

Abstract: A method for selectively diffusing a semiconductor body with p-conductivity type impurities utilizing aluminum as a diffusion source and able to be performed in a reuseable open diffusion tube is described. A gas flow is established in the diffusion tube which is essentially an inert gas and includes from one to ten percent oxygen. Simultaneous blanket and selective diffusions may be formed in accordance with this invention by modifying the amount of oxygen in the flow.

Abstract: The optocoupling between an optical source and an optical sensor is enhanced while retaining a high dielectric strength by providing a homogeneous medium surrounding the source and the sensor having an inner light transmissive region and an outer light reflective region encapsulated within a substantially opaque body. The homogeneous medium is formed by applying an optically transmissive material to the source and sensor and no more than partially curing said material before applying an optically reflective material which, when fully cured along with the optically transmissive material, does not form an isolation degrading boundary therebetween.

Abstract: Disclosed is a method of manufacturing a metal oxide varistor body. Conventional manufacturing techniques through sintering are utilized on any metal oxide varistor formulation which includes bismuth oxide. Following sintering, the devices are heat treated at a temperature between 750.degree. C. and 1200.degree. C. for a time in excess of about 10 hours. The heat treatment increases the alpha of the devices and substantially lowers the leakage current.

Abstract: Disclosed is a rectifier pellet and a method for the fabrication thereof. A layer of oxide is grown on a semiconductor wafer that has been diffused to form a plurality of rectifier pellets, and openings are etched in the oxide at locations corresponding to each pellet. Gold is diffused through the openings into a preselected distribution to reduce turnoff time. Grooves are etched to facilitate glass passivation and division of the wafer into pellets.

Abstract: This invention relates to a system for separating a semiconductor wafer into a plurality of discrete pellets while maintaining the relative orientation that the pellets exhibited when in the wafer. The invention is carried out by first applying a ductile variable coupling layer to a surface of the wafer. The coupling layer is affixed to a stretchable membrane which, after the wafer is subdivided, is stretched to space the pellets from one another. The coupling material adheres more tightly to the membrane than to the wafer. A portion of the bond between the ductile coupling layer and the membrane is broken during stretch so that the pellets adhere less tightly to the coupling layer following stretch than prior thereto.

Abstract: A method for dividing a semiconductor wafer into pellets includes attaching the wafer to a vinyl membrane with a coupling material which adheres more tenaciously to the membrane than to the pellets and sawing completely through the wafer and at least partially through the coupling material to separate the wafer into discrete pellets. In accordance with a preferred method, the membrane is at least slightly cut by the saw to insure complete division of the wafer. The pellets are readily removed from the coated membrane without any residues remaining thereon from the coupling material. A resinous vinyl coupling material is preferred.

Abstract: In one implementation of the inventive method an aircraft with an antenna mounted thereon is compelled to follow a sinuous path. The antenna normally provide 120.degree. coverage on either side of the aircraft. Full 360.degree. coverage is provided by the same antenna as the aircraft traverses the predetermined sinuous path.