Misfit Dislocation Generation for MBE Grown GaAs on In-Doped LEC-GaAs Substrates

Abstract
Nearly dislocation-free indium-doped LEC-GaAs crystals are applied to substrates for MBE-GaAs growth. Misfit dislocation generation at the epi-layer/substrate interface is found by electron beam induced current method. The critical trhickness for generating misfit dislocations agrees with theoretical predictions. The relationship between the critical thickness and indium concentration is deduced. This result suggests that misfit dislocations generate at small epi-layer thickness (< 1.5 µm) when the indium concentration is more than 5×1019/cm3.
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