Rca Inc.

US Government As Represented by the Secretary of the Army

Jonathan Isaac Gittleman

Benjamin Abeles

Harry Louis Pinch

Robert Alfred Bartolini

Stanley Bozowski

A device for non-destructive surface photovoltage testing of silicon-on-sapphire (SOS) wafers employs the electrically equivalent of an inserted capacitance in series in a measuring circuit. A pair of thin irridescent coated (TIC) glasses, are positioned on each side of an SOS wafer with an electrical lead attached to each of the conductive coating of tin oxide and indium tin oxide of the TIC glasses. The glass surface (the non-conductive side) of each TIC glass is positioned adjacent to the sapphire layer and silicon layer respectively. An incident light illuminates the sapphire layer and subsequently illuminates the silicon-sapphire interface with a predetermined wave length of light wherein the silicon absorbs all of the light within about 100A of the silicon-sapphire interface. Thus, the incident light is transmitted through the conductive layer of the first TIC glass which is in electrical contact with a detection circuit. The second TIC glass conductive layer is in electrical contact with a calibration signal input which completes the measuring circuit. The measuring circuit with the electrical equivalent of a capacitor in series is able to detect the altered signal resulting from surface photovoltage (SPV) charge due to absorbed incident light which is a measure of the sapphire-silicon interface condition to permit a non-destructive SPV testing of SOS wafers, greatly speeding the pre-selection process of SOS wafers.

Non-destructive testing of SOS wafers using surface photovoltage

A multi-layer optical record blank and information record comprises a light-reflective layer, a light-transmissive layer, a light-absorptive layer, and a heat-sensitive information layer wherein the thicknesses of the layers are chosen to achieve a low-reflection condition. Information is recorded as variations of an optical property in the information layer indirectly heated by light absorbed in the absorptive layer.

Optical record blank and information record

A cermet film includes metal particles in an insulator with the metal particles having an average diameter of from about 30A to about 120A. The cermet film has a high resistivity, and low temperature coefficient of resistivity, and is stable under electric fields of up to 10.sup.5 volts/cm. The cermet film can be formed by co-sputtering the metal and the insulator onto a substrate. The sputtered cermet film is then annealed in a reducing atmosphere whereby its resistivity is increased without a corresponding change in its temperature coefficient of resistivity.

Method of making high resistance cermet film

A layer of electrically insulating material is coated on a reflector. Granular semiconductor particles are uniformly dispersed in the layer of electrically insulating material. The combination forms an efficient absorber for high temperature photothermal conversion of solar energy.

Growing community of inventors

Trenton, NJ, United States of America

Jonathan Isaac Gittleman