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Castle, J. G.

Publications and source records attributed to Castle, J. G..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1976

Space processing of crystalline materials: A study of known methods of electrical characterization of semiconductors

A literature survey is presented covering nondestructive methods of electrical characterization of semiconductors. A synopsis of each technique deals with the applicability of the techniques to various device parameters and to potential in-flight use before, during, and after growth experiments on space flights. It is concluded that the very recent surge in the commercial production of large scale integrated circuitry and other semiconductor arrays requiring uniformity on the scale of a few microns, involves nondestructive test procedures which could well be useful to NASA for in-flight use in space processing.

Castle, J. G.↗
NASA NTRS1975

Electrical characterization of GaAs single crystal in direct support of M555 flight experiment

An exploration of several nondestructive methods of electrical characterization of semiconductor single crystals was carried out. Two methods of obtaining the microwave skin depth, one for mapping flat surfaces and the other for analyzing the whole surface of small single crystal wafers, were developed to the stage of working laboratory procedures. The preliminary 35 GHz data characterizing the two types of space related single crystal surfaces, flat slices of gallium arsenide and small wafers of germanium selenide, are discussed. A third method of nondestructive mapping of donor impurity density in semiconductor surfaces by scanning with a light beam was developed for GaAs; its testing indicates reasonable precision at reasonable scan rates for GaAs surfaces at room temperature.

Castle, J. G.↗
NASA NTRS1975

Electrical characterization of GaAs single crystal in direct support of M555 flight experiment

The exploration of several nondestructive methods of electrical characterization of semiconductor single crystals was carried out during the period ending May 1974. Two methods of obtaining the microwave skin depth, one for the mapping flat surfaces and the other for analyzing the whole surface of small single crystal wafers, were developed to the stage of working laboratory procedures. The preliminary 35 GHz data characterizing the two types of space-related single crystal surfaces, flat slices of gallium arsenide and small wafers of germanium selenide, are discussed. A third method of nondestructive mapping of donor impurity density in semiconductor surfaces by scanning with a light beam was developed for GaAs; its testing indicates reasonable precision at reasonable scan rates for GaAs surfaces at room temperature.

Castle, J. G.↗
NASA NTRS1972

Improved electrodes for skin contacts

Design is described of thick, flexible electrodes with appropriate metal surfaces which prevent unnecessary skin motion. Electrodes provide sufficient radial pressure directed toward body surface to depress skin a noticeable portion of its normal resilient thickness.

Castle, J. G.↗