Growth of InSb films on a Si(001) substrate with Ge buffer layer

InSb films were grown on Si(001) substrates by molecular beam epitaxy using Ge buffer layers with thickness up to 1000 ML (monolayer). The surface morphology of Ge layers on which heteroepitaxy of InSb film is achieved, was observed using atomic force microscope (AFM) The density of Ge islands on Si(001) substrate rapidly increased with increase in the thickness of Ge layer (d(Ge)). X-ray diffraction (XRD) measurements were performed to characterize the InSb films. The dependence of the crystal quality of InSb films on d(Ge) was studied. The intensity of the InSb(004) peak was substantially enhanced with the increase in d(Ge) compared to the other diffraction peaks. These results indicate that the enhancement of intensity of the InSb(004) peak is correlated with the increase in the areal density of Ge islands which facilitate the heteroepitaxial growth of InSb films.