Formation of type-II InAs/GaSb strained short-period superlattices for IR photodetectors by molecular beam epitaxy

Abstract

The interaction of the GaSb(001) surface with fluxes of As2, As4, and Sb4 molecules is studied using reflection high-energy electron diffraction. It is shown that As2 molecules interact with a GaSb surface predominantly by an exchange mechanism, and As4 molecules by the vacancy mechanism. It is established that for the reproducible generation of In-Sb heterointerfaces in InAs/GaSb superlattices, one needs to use a flux of As4 molecules rather than As2 molecules.