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Clough, R.

Publications and source records attributed to Clough, R..

11 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

NBS: Nondestructive evaluation of nonuniformities in 2219 aluminum alloy plate: Relationship to processing

The compositional homogeneity, microstructure, hardness, electrical conductivity and mechanical properties of 2219 aluminum alloy plates are influenced by the process variables during casting, rolling and thermomechanical treatment. The details of these relationships wre investigated for correctly processed 2219 plate as well as for deviations caused by improper quenching after solution heat treatment. Primary emphasis was been placed on the reliability of eddy current electrical conductivity and hardness as NDE tools to detect variations in mechanical properties.

Swartzendruber, L.↗
NASA NTRS1970

P-n junctions formed in gallium antimonide

Vapor phase deposition process forms a heavily doped n-region on a melt-grown p-type gallium antimonide substrate. HCl transports gallium to the reaction zone, where it combines with antimony hydride and the dopant carrier, hydrogen telluride. Temperatures as low as 400 degrees C are required.

Clough, R.↗
NASA NTRS1970

Growth of single-crystal gallium nitride

Use of ultrahigh purity ammonia prevents oxygen contamination of GaN during growth, making it possible to grow the GaN at temperatures as high as 825 degrees C, at which point single crystal wafers are deposited on /0001/-oriented sapphire surfaces.

Clough, R.↗
NASA NTRS1970

Visible light electroluminescent diodes of indium-gallium phosphide

Vapor deposition and acceptor impurity diffusion techniques are used to prepare indium-gallium phosphide junctions. Certain problems in preparation are overcome by altering gas flow conditions and by increasing the concentration of phosphine in the gas. A general formula is given for the alloy's composition.

Clough, R.↗