Structure and carrier lifetime in LT-GaAs

Journal Article · Wed Dec 01 04:00:00 EST 1993 · Journal of Electronic Materials

DOI:https://doi.org/10.1007/BF02650000· OSTI ID:535224

Liliental-Weber, Z ^[1]; Cheng, H J; Gupta, S ^[2]

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1. Lawrence Berkeley Lab., CA (United States)
2. Univ. of Michigan, Ann Arbor, MI (United States); and others

The relationship between the structural quality of low-temperature GaAs layers and the photoexcited carrier lifetime has been studied. Transmission electron microscopy, x-ray rocking curves, time-resolved reflectance methods, and photoconductive-switch-response measurements were used for this study. For a variety of samples grown at temperatures in the vicinity of 200{degrees}C, subpicosecond carrier lifetimes were observed both in as-grown layers, as well as in the same layers after post-annealing and formation of As precipitates. These results suggest that the carrier lifetime, which was found to be shorter in the as-grown layers than in the annealed ones, might be related to the density of As{sub Ga} antisite defects present in the layers. The annealed layers which contained structural defects before annealing appeared to exhibit the longest carrier lifetime due to gathering of As on these defects (and formation of relatively large As precipitates) and depletion of extra As (As{sub Ga}) defects from the layer. It was found as well that the responsivity of detectors fabricated on these layers depended strongly on the structural quality of the layers, with the greatest response obtained not for the layers with the fewest defects, but for the layers with 10{sup 7}-10{sup 8}/cm{sup 2} of pyramidal defects. 14 refs., 4 figs.

• Sponsoring Organization: USDOE
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 535224
• Journal Information: Journal of Electronic Materials, Journal Name: Journal of Electronic Materials Journal Issue: 12 Vol. 22; ISSN JECMA5; ISSN 0361-5235
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ANNEALING
CARRIER LIFETIME
CRYSTAL DEFECTS
ELECTRICAL PROPERTIES
GALLIUM ARSENIDES
LAYERS
TRANSMISSION ELECTRON MICROSCOPY