Nonlinear dependence of X-ray diffraction peak broadening in InxGa1-xSb epitaxial layers on GaAs substrates

Abstract

The configuration of the interfacial misfit array at InxGa1-xSb/GaAs interfaces with different indium compositions and thicknesses grown by metalorganic chemical vapor deposition was systematically analyzed using X-ray diffraction (XRD) reciprocal space maps (RSMs). These analyses confirmed that the epilayer relaxation was mainly contributed to by the high degree of spatial correlation of the 90 degrees misfit array (correlation factors <0.01). The anisotropic peak-broadening aspect ratio was found to have a non-linear composition dependence as well as be thickness-dependent, related to the strain relaxation of the epilayer. However, the peak-broadening behavior in each RSM scan direction had different composition and thickness dependences. (c) 2018 The Japan Society of Applied Physics