Thin InSb films on GaAs substrates by molecular beam epitaxy

We optimized the suitable growth conditions for obtaining smooth surface and high-quality InSb epilayer grown on semi-insulating GaAs substrate. The low temperature (LT) buffer layer was introduced into the growth process to improve the surface morphology and interface quality of the epilayers. It was confirmed that high quality InSb epilayer strongly depends on LT InSb buffer layer and growth conditions and parameters. Our typical InSb samples were obtained at the growth temperature of 420-425 degrees C, with the optimum Sb/In ratio of 1.4 : 1, and in our experiments, the epilayer thickness was in the range of 1.0 to 2.2 mu m. Typically, the room temperature X-ray diffraction (XRD) full width half maximum (FWHM) of 172 '' and mobility of 64300 cm(2) V-1 S-1 at 77 K were obtained for typical sample of 2.2 mu m thickness.