Effect of As2 and As4 fluxes on the morphology of GaSb(001) surface during growth of GaSb/InAs heterojunction by MBE

摘要

Interaction of GaSb(001) surface with fluxes of As2, As4 and Sb4 molecules was investigated on the basis of the reflection high energy electron diffraction (RHEED) method. Exposure of GaSb surface to As2 and As4 fluxes results in substitution of antimony atoms by arsenic atoms. It is shown that As2 molecules interact with GaSb surface mostly on the basis of the direct substitution mechanism, while As4 molecules interact with it on the basis of the vacancy mechanism. It has been found that for reproducible generation of In-Sb heteroboundaries in InAs/GaSb super-lattices it is necessary to use As4 flux rather than As2 one. The research results have allowed optimizing the technology for growth of short-period InAs/GaSb superlattices that have high potential for development of IR photodetectors.