TEM studies of epitaxial CdTe and (Hg, Cd)Te grown by MOVPE on GaAs and CdTe substrates

Abstract

Epitaxial layers of {111}-oriented CdTe have been grown on {111}A CdTe, {111}B GaAs and {100} GaAs by MOVPE. Cross-sectional transmission electron microscope (TEM) studies have revealed the presence of many lamella twins lying parallel to the substrate-layer interface in all of these layers. In contrast, {100} CdTe deposited onto {100} GaAs exhibits a large number of misfit dislocations at the interface. A structural comparison of epitaxial layers of (Hg, Cd)Te deposited onto CdTe/{111}B GaAs hybrid substrates and onto bulk {111}A CdTe substrates is also reported.