Structure and morphology of InSb epitaxial films in the AlAs matrix

Abstract

We report the results of electron microscopy study of the structural and morphological features of epitaxial films in the AlAs matrix. The epitaxial films were grown in the matrix by deposition of indium and antimony from molecular flows onto the aluminum arsenide surface and subsequent deposition of aluminum and arsenic. The objects of study were (110) cross sections and (001) planar foils. Instead of the InSb binary compound, we found the In_xAl_1–xSb_yAs_1–y quaternary solid solution in the AlAs matrix in the form of a wetting layer with coherently conjugated and relaxed islands. The In and Sb contents in the solid solution were indirectly estimated. Misfit dislocations at the heterointerfaces of relaxed islands were analyzed using the geometric phase method. It was established that each misfit dislocation is formed by a pair of close 60° dislocations with the inclined Burgers vectors of the a/2〈110⟩ type. In this case, the resulting Burgers vector of each pair lies in the heterointerface plane.