Incorporation of Sb and As in MBE grown GaAsxSb1−x layers

Abstract

With the increasing interest in low effective mass materials for intersubband devices, mixed As-Sb compounds, like GaAsxSb1−x or AlxIn1−xAsySb1−y, gain more and more attention. The growth of these materials, however, still provides significant challenges due to the complex interaction between As and Sb. In this work, we provide an in-depth study on the incorporation of Sb into the GaAsxSb1−x layers and compare our findings to the present literature on this topic. It is found that both the composition and the crystal quality of GaAsxSb1−x layers are strongly influenced by the growth rate due to the As-for-Sb exchange reaction which takes place at the growing surface, and that high crystal quality can be achieved when the growth is performed under Sb limited conditions.