Effect of InAs Thickness on the Structural and the Electrical Properties of InAs Layers Grown on GaAs Substrates with an AlAs_(0.32)Sb_(0.68) Buffer Layer

摘要

InAs layers on GaAs substrates with AlAs_(0.32)Sb_(0.68) buffer layers were grown by using molecular beam epitaxy. X-ray diffraction patterns showed that the dominant peaks corresponding to the GaAs, InAs, and AlAs_(0.32)Sb_(0.68) layers appeared. Atomic force microscopy images showed that the root-mean-square surface roughness of the InAs surface increased with increasing thickness of the InAs layer due to the lattice-constant difference between the InAs and the AlAs_(0.32)Sb_(0.68) layers, resulting in relaxation of the strain in the InAs layer. Hall effect measurements at 300 K showed that the electron mobility increased with increasing InAs film thickness.