The growth of high quality CdTe on GaAs by molecular beam epitaxy

Journal Article · Thu Mar 01 00:00:00 EST 1990 · Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA)

DOI:https://doi.org/10.1116/1.576997· OSTI ID:6976154

Reno, J L; Carr, M J; Gourley, P L ^[1]

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1. Sandia National Laboratories, Albuquerque, New Mexico 87185 (US)

We have grown CdTe (111) on oriented and misoriented GaAs (100) and have characterized the layers by photoluminescence microscopy (PLM) and transmission electron microscopy (TEM). Photoluminescence microscopy showed a totally different type of defect structure for the oriented substrate than for the misoriented substrates. The CdTe grown on the misoriented substrates exhibited only threading dislocations. The CdTe grown on oriented GaAs showed fewer threading dislocations but exhibited a random structure of loops. The loop structure observed by PLM has been identified by TEM as the boundary between twinned crystallites which extend from the CdTe/GaAs interface to the CdTe surface. When viewed along the growth axis, these boundaries between the columnar twins appear as loops and segments. Surface roughness of the GaAs substrate contributes to the initial growth of twinned material. This leads to competitive growth between the twins and the creation of the observed columnar twins. We present for the first time the growth of CdTe on patterned GaAs substrates. By growing on oriented GaAs(100) substrates that had been patterned prior to growth with 12 {mu}m mesas, it is possible to grow material on the mesa top that is twin free and has a low dislocation density.

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6976154
• Journal Information: Journal of Vacuum Science and Technology, A (Vacuum, Surfaces and Films); (USA), Vol. 8:2; ISSN 0734-2101
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CADMIUM TELLURIDES
SEMICONDUCTOR MATERIALS
GALLIUM ARSENIDES
MERCURY COMPOUNDS
THIN FILMS
MEASURING METHODS
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
SORPTION
TRANSMISSION ELECTRON MICROSCOPY
ARSENIC COMPOUNDS
ARSENIDES
CADMIUM COMPOUNDS
CHALCOGENIDES
ELECTRON MICROSCOPY
EPITAXY
FILMS
GALLIUM COMPOUNDS
LUMINESCENCE
MATERIALS
MICROSCOPY
PNICTIDES
TELLURIDES
TELLURIUM COMPOUNDS
360603* - Materials- Properties