Assessment of structural properties of InAs/GaSb superlattice by double crystal X-Ray diffraction and cross-sectional scanning tunnelling microscopy

An investigation of the structural properties of InAs / GaSb superlattices was carried out by double crystal X-ray diffraction analysis and cross-sectional scanning tunnelling microscopy. It was demonstrated that the combination of these methods make it possible to describe in sufficient details the thickness and composition of the alternating layers as well as characterize the interfaces between them. The effect of MBE growth conditions (Sb flux) on the cation and anion segregation profiles and interface bond formation was studied. It was suggested that the use of high Sb flux during the GaSb growth helps to minimize As-for-Sb exchange at the InAs-on-GaSb heterojunction and preserve In-Sb type bonds. (author)