Growth and characterization of InAsSb layers on GaSb substrates by liquid phase epitaxy

Abstract

High quality InAs1−xSbx semiconductor films were successfully grown on (100) GaSb single crystal substrates using liquid phase epitaxy technique (LPE). The crystalline structure and lattice mismatch between film and substrate were investigated by high-resolution X-ray diffraction (HRXRD). The surface roughness and the interface morphology of the epitaxial film-on-substrate were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) and optical microscopy. These results show the high-purity InAs1−xSbx epitaxial layers with mirror-like surface and rms ranges from 0.5 to 2nm, and a sharp interface between substrate and ternary film. The optical properties of the layers were studied by low temperature photoluminescence (PL) spectroscopy. PL spectrum of the ternary film shows one radiative emission peak with narrow full width at half-maximum, which is an evidence of the good crystalline quality of the epilayer. It is worth to mention that the InAsSb films were grown on GaSb substrates for compositions of Sb with x=0.16 without introducing any intermediate composition buffer layer between the GaSb substrate and the film as reported in previous works.