Structure of vapor-deposited GaxIn1−xAs crystals

Abstract

Deformation of the crystal lattice of layers of Ga x In1−x As (0.5 < x < 1.0) grown onto GaAs substrates by a chemical vapor deposition process was investigated. For this study, Ga and In were transported as chlorides with HCl and AsH3 was the source of As. It was observed that the lattice constant along the direction of the film thickness was larger than that along the surface. This fact indicates that the crystal lattice of Ga x In1−x As is compressed along the substrate surface as a result of lattice mismatch. The influence of both the composition of the epitaxial layers and the crystal plane of the substrate surface on the degree of this deformation was investigated. It was also found that the epitaxial orientation grew inclined to the substrate crystal when the crystal surface of the substrate was {100} or {110}.