Abstract: Structured materials for photonic devices, at wavelengths of X-ray, ultraviolet, visible, infrared and microwave radiation, can be made using layer growth techniques. Such a structure can be made layer by layer, by homogeneous deposition followed by localized modification for refractive index differentiation. Alternatively, the structure can be made by simultaneous growth of regions whose refractive index differs. The structures can be used as selective bandpass filters, and in photovoltaic solar cells, for example.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: Glow discharge method and apparatus useful for coating photoresponsive devices in the form of drums and plates are described. Improved photoresponsive devices using amorphous silicon which accepts a high surface voltage in the dark and discharges to a low residual voltage under illumination are also described.

Abstract: Glow discharge method and apparatus useful for coating electrophotographic photoreceptors in the form of drums and plates are described. Improved photoreceptors using amorphous silicon which accepts a high surface voltage in the dark and discharges to a low residual voltage under illumination are also described.

Abstract: Glow discharge method and apparatus useful for coating electrophotographic photoreceptors in the form of drums and plates are described. Improved photoreceptors using amorphous silicon which accepts a high surface voltage in the dark and discharges to a low residual voltage under illumination are also described.

Abstract: Photovoltaic junctions useful for solar energy conversion and for electrophotographic image formation are fabricated from a layer of amorphous boron in contact with a layer of amorphous silicon. The amorphous boron is preferably deposited at a reduced temperature on the amorphous silicon; or, alternatively, the amorphous silicon is deposited on a boron-bearing body previously deposited on an opaque metallic substrate.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: A heat exchanger with an auxiliary cooling system capable of cooling a nuclear reactor should the normal cooling mechanism become inoperable. A cooling coil is disposed around vertical heat transfer tubes that carry secondary coolant therethrough and is located in a downward flow of primary coolant that passes in heat transfer relationship with both the cooling coil and the vertical heat transfer tubes. A third coolant is pumped through the cooling coil which absorbs heat from the primary coolant which increases the downward flow of the primary coolant thereby increasing the natural circulation of the primary coolant through the nuclear reactor.

Abstract: In a gaseous glow-discharge process for coating a substrate with semiconductor material, a variable electric field in the region of the substrate and the pressure of the gaseous material are controlled to produce a uniform coating having useful semiconducting properties. Electrodes having concave and cylindrical configurations are used to produce a spacially varying electric field. Twin electrodes are used to enable the use of an AC power supply and collect a substantial part of the coating on the substrate. Solid semiconductor material is evaporated and sputtered into the glow discharge to control the discharge and improve the coating. Schottky barrier and solar cell structures are fabricated from the semiconductor coating. Activated nitrogen species is used to increase the barrier height of Schottky barriers.

Abstract: Separation of U.sup.235 and U.sup.238 isotopes by converting a mixture of these isotopes to organic compounds or to silicon compounds and then irradiating the isotope compounds selectively to change their chemical (and/or physical) properties, thereby to facilitate separation. In a preferred embodiment of the invention the uranium compounds are selected from the group having a chemical moiety R bonded directly to the U atom, the U-R bond having a fundamental, overtone, or combination virbational absorption frequency between 900 and 1100 cm.sup.-1. The selected U mixture is then irradiated with a frequency-selective CO.sub.2 laser.