Abstract: A method of producing sheets of crystalline material is disclosed, as well as devices employing such sheets. In the method, a growth mask is formed upon a substrate and crystalline material is grown at areas of the substrate exposed through the mask and laterally over the surface of the mask to form a sheet of crystalline material. This sheet is optionally separated so that the substrate can be reused. The method has particular importance in forming sheets of crystalline semiconductor material for use in solid state devices.

Abstract: A display panel is formed using a single crystal thin-film material that may be transferred to substrates for display fabrication. Pixel arrays form light valves or switches that can be fabricated with control electronics in the thin-film material prior to transfer. The resulting circuit panel is then incorporated into a display panel with a light emitting or liquid crystal material to provide the desired display.

Abstract: Light emitting diodes (LEDs) and LED bars and LED arrays formed of semiconductive material, such as III-V, and particularly AlGaAs/GaAs material, are formed in very thin structures using organometallic vapor deposition (OMCVD). Semiconductor p-n junctions are formed as deposited using carbon as the p-type impurity dopant. Various lift-off methods are described which permit back side processing when the growth substrate is removed and also enable device registration for LED bars and arrays to be maintained.

Abstract: A method of producing sheets of crystalline material is disclosed, as well as devices employing such sheets. In the method, a growth mask is formed upon a substrate and crystalline material is grown at areas of the substrate exposed through the mask and laterally over the surface of the mask to form a sheet of crystalline material. This sheet is optionally separated so that the substrate can be reused. The method has particular importance in forming sheets of crystalline semiconductor material for use in solid state devices.

Abstract: A display panel is formed using essentially single crystal thin-film material that is transferred to substrates for display fabrication. Pixel arrays form light valves or switches that can be fabricated with control electronics in the thin-film material prior to transfer. The resulting circuit panel is than incorporated into a display panel with a light emitting or liquid crystal material to provide the desired display.

Abstract: A method of producing sheets of crystalline material is disclosed, as well as devices employing such sheets. In the method, a growth mask is formed upon a substrate and crystalline material is grown at areas of the substrate exposed through the mask and laterally over the surface of the mask to form a sheet of crystalline mateGOVERNMENT SUPPORTWork described herein was supported by the U.S. Air Force.

Abstract: A method of forming gallium arsenide on silicon heterostructure including the use of strained layer superlattices in combination with rapid thermal annealing to achieve a reduced threading dislocation density in the epilayers. Strain energy within the superlattices causes threading dislocations to bend, preventing propagation through the superlattices to the epilayer. Rapid thermal annealing causes extensive realignment and annihilation of dislocations of opposite Burgers vectors and a further reduction of threading dislocations in the epilayer.

Abstract: A display panel is formed using essentially single crystal thin-film material that is transferred to substrates for display fabrication. Pixel arrays form light valves or switches that can be fabricated with control electronics in the thin-film material prior to transfer. The resulting circuit panel is than incorporated into a display panel with a light emitting or liquid crystal material to provide the desired display.

Abstract: An apparatus for responding to incident electromagnetic radiation includes a first medium having a surface and through which incident electromagnetic radiation may be transmitted, a second such medium having a surface, the surfaces being generally parallel, and smectic liquid crystal between said surfaces and aligned generally in parallel in layers that extend generally parallel to each other and perpendicularly to such surfaces (bookshelf alignment), the liquid crystal material being operative to undergo self-focusing in response to a characteristic of incident electromagnetic radiation exceeding a value and being cooperative with at least one of such media thereby automatically to limit the energy or energy density of electromagnetic radiation exiting the apparatus.

Abstract: A photovoltaic device utilizing compound semiconductor materials that are stable when operated at high temperatures. Hostile environments, and in particular, thermally stressful environments such as those generated by use of light concentrating systems, require encapsulation of the device. Sealing of the photo-active junction, the conductive grid, the exposed semiconductor surfaces, and the pads contacting the grid away from the junction area provide such thermal stability. A heterojunction structure can be used along with barrier materials providing a conductive grid in contact with the photo-active surface thereby reducing interdiffusion of that surface with the conductive grid.

Abstract: Dislocation densities are reduced in growing semiconductors from the vapor phase by employing a technique of interrupting growth, cooling the layer so far deposited, and then repeating the process until a high quality active top layer is achieved. The method of interrupted growth, coupled with thermal cycling, permits dislocations to be trapped in the initial stages of epitaxial growth.

Abstract: An monolithic integrated transceiver formed on an Si substrate comprising: a III-V compound light source, a III-V compound light detector and a pyramidal groove formed in the substrate for aligning an optical fiber with said transmitter.

Abstract: An optical device formed on an Si substrate comprising: a III-V optical transmitter formed on the Si substrate, a silicon device formed in or on, the Si substrate and an alignment groove formed in the substrate for aligning an optical fiber with said transmitter.

Abstract: A photovoltaic device utilizing compound semiconductor materials that are stable when operated at high temperatures. Hostile environments, and in particular, thermally stressful enviornments such as those generated by use of light concentrating systems, require encapsulation of the device. Sealing of the photo-active junction, the conductive grid, the exposed semiconductor surfaces, and the pads contacting the grid away from the junction area provide such thermal stability. A heterojunction structure can be used along with barrier materials providing a conductive grid in contact with the photo-active surface thereby reducing interdiffusion of that surface with the conductive grid.

Abstract: An improved method of zone-melting and recrystallizing of polysilicon film on an insulator over silicon is described.

Abstract: A method for reducing the defect and dislocation density in III-V material layers deposited on dissimilar substrates is disclosed. The method involves ion implantation of dopant materials to create amorphous regions within the layers followed by an annealing step during which the amorphous regions are recrystallized to form substantially monocrystalline regions. The wafers produced by the process are particularly well suited for optoelectronic devices.

Abstract: An improved method and apparatus for optimizing the electrical properties while crystallizing material is disclosed. In this invention, a material which is to be crystallized is formed on a substrate and subjected to a heat treatment to intentionally induce thermal stress while crystallizing the material. The heat treatment melts the material being crystallized and when the material solidifies, a built-in stress is retained which, in the case of n-doped Si on fused silica results in a tensile stress which produces an electron mobility in the film of 870 cm.sup.2 /volt-sec as compared to similarly fashioned unstressed n-doped Si on SiO.sub.2 coated Si which has an electron mobility of 500 cm.sup.2 /volt-sec.

Abstract: A reactor, suitable for CVD processes, which presents a high aspect ratio to reactant gasses, is described. Substrates are mounted on oppositely disposed susceptors in a vertical chimney-type reactor. Means are provided to rotate the susceptors about an axis perpendicular to gas flow. Side-loading or top-loading mechanisms are provided for loading and unloading the susceptors through a gate valve. A diffuser below the reaction zone adjusts the gas flow into the reaction zone.

Abstract: A method of producing sheets of crystalline material is disclosed, as well as devices employing such sheets. In the method, a growth mask is formed upon a substrate and crystalline material is grown at areas of the substrate exposed through the mask and laterally over the surface of the mask to form a sheet of crystalline material. This sheet is optionally separated so that the substrate can be reused. The method has particular importance in forming sheets of crystalline semiconductor material for use in solid state devices.

Abstract: Transparent heat-mirrors are disclosed which are comprised of composite films. These films include a discrete and continuous layer of metallic silver sandwiched between a transparent, outer, protective, anti-reflection layer and a transparent, phase-matching layer. This combination of layers is chosen to provide high solar transmission with minimum loss of thermal radiation. Transparent heat-mirrors are useful in the collection and trapping of solar energy, and in other applications where it is desired or necessary to have high infrared reflectivity with high solar transmission.