Vapor Transport Crystal Growth of Mercury-Cadmium-Telluride in Microgravity

Heribert Wiedemeier

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NASA NTRS · 19950007802

Vapor Transport Crystal Growth of Mercury-Cadmium-Telluride in Microgravity

Heribert Wiedemeier

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Abstract

Two epitaxial growth experiments of Hg 1-x Cd x Te layers on (100) CdTe substrates in closed ampoules using HgI 2 as a transport agent have been performed during the USML-1 mission. The characterization results to date demonstrate a considerable improvement of the space-grown epitaxial layers relative to ground-control specimens in terms of morphology, compositional uniformity, and structural micro homogeneity. These results show the effects of microgravity and fluid dynamic disturbances on-ground on the deposition and growth processes. The continued analysis of this technologically important system is designed to further elucidate the observed crystallographic improvements and their relation to mass flow.

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Heribert Wiedemeier. 1994-05-01. Vapor Transport Crystal Growth of Mercury-Cadmium-Telluride in Microgravity. https://ntrs.nasa.gov/citations/19950007802

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