Abstract: A light responsive device (10) has a body (12) that includes a matrix comprised of Group III-V material, the matrix having inclusions (14) comprised of a Group V material contained therein. The body is responsive to a presence of a light beam that has a spatially varying intensity for modifying in a corresponding spatially varying manner a distribution of trapped photoexcited charge carriers within the body. The distribution of trapped charge carriers induces a corresponding spatial variation in at least one optical property of the Group III-V material, such as the index of refraction of the Group III-V material and/or an absorption coefficient of the Group III-V material. The Group III-V material is comprised of LTG GaAs:As or LTG AlGaAs:As.

Abstract: A semiconductor device where an emitter material composition and doping profile produces an electron gas in a base adjacent a band offset heterojunction interface, the electrons in the electron gas in the base are confined under bias by a low barrier and the ballistic carriers have their kinetic energy controlled to prevent intervalley scattering by an electrostatic barrier that under influence of bias provides an essentially level conduction band in the portion of the base adjacent the collector.

Abstract: A surface termination of a compound semiconductor is provided wherein conditions are provided for a pristine surface to be retained in an unpinned condition and a surface layer of a non-metallic material is provided. A GaAs substrate is heated in an oxygen-free atmosphere at high temperature with hydrogen sulfide, producing a pristine surface with a coating of gallium sulfide covered with a 1,000 nanometer covering of low temperature plasma enhanced chemical vapor deposited silicon dioxide.

Abstract: An electrical device which employs two-dimensional space charge modulation in a semiconductor structure. The device has an approximately Debye length wide contact and a rectifying contact positioned adjacent to each other within a Debye length on a semiconductor body and a contact remotely positioned. A bias on the rectifying contact will effect conduction between the other contacts.

Abstract: Crystalline compound semiconductors are passivated with a layer of the most volatile element thereof to prevent the formation of oxides that would interfere with further processing. A GaAs crystal is provided with a surface layer of arsenic. The arsenic layer is formed by exposure to light having a photon energy greater than 1.8 eV, at a power density of 0.01 to 0.5 watts per cm.sup.2 while the GaAs immersed in a 1:1 HCl:H.sub.2 O solution for a period of 10-30 minutes. The intermediate processing passivated GaAs crystal may be stored and handled in air and the As layer is removed by low temperature baking.

Abstract: In a molecular beam epitaxy furnace, a heater is described for heating the interior of an effusion cell. The heater includes an outer cylindrical sleeve having one end connected to receive a vacuum, and an opposite end extending into the furnace. An inner sleeve is provided coaxial with the outer cylindrical sleeve, one end of the inner sleeve being sealed with the opposite end of the cylindrical sleeve. The inner sleeve extends along a portion of the outer cylindrical sleeve providing an interior vacuum chamber. A heating element is disposed between the cylindrical sleeve and inner sleeve which heats the interior crucible receiving chamber and a crucible therein bearing semiconductor constituent material such that the semiconductor constituent material effuses without contamination from the heating element.

Abstract: A refractory compound structure comprising a substrate of a compound which is a combination of a refractory and/or metallic element and a nonmetallic element and an elemental layer of the refractory and/or metallic element on the substrate is formed by heating the refractory compound in a vacuum at a decomposition temperature for the refractory compound.

Abstract: When growing GaAs by molecular beam epitaxy (MBE), a typical related reaction acts to affix Ga.sub.2 O.sub.3 to the growth surface and hence incorporates such oxide contaminants in the epitaxial layer as it is grown. Such contaminants may yield crystals of poor electrical and optical properties. When Al is added to the Ga source crucible, the Ga.sub.2 O flux is reduced substantially thereby suppressing the formation of such oxide contaminants and remove a serious constraint to MBE growth. When doping GaAs with Mg to form a p-type GaAs layer, unity Mg doping efficiency is achieved by including 0.1% Al in the Ga effusion cell. Such an inclusion of Al improves the Mg doping efficiency by suppressing the formation of MgO, and allows MBE growth at lower substrate temperatures and at higher growth rates.

Abstract: A semiconductor device of the ballistic type, wherein the carrier transport in the body of the device from one electrode to the other takes place essentially free of collisions, is fabricated with a semiconductor body having a long mean-free path, a body width between ohmic electrodes that is less than or equal to the product of the velocity of a carrier and the time to a collision, but more than the distance that will permit quantum mechanical tunnelling, an impressed voltage less than required for an intervalley carrier transition and having the ohmic external contact on each surface of the body free of any barrier to carrier flow. A ballistic type triode device is provided with a current modulating electrode included within the body of the device.