Homo- and hetero-epitaxial growth of InSb and AlxIn1−xSb layers by molecular beam epitaxy

Al_xIn_1-xSb and InSb layers have been grown by molecular beam epitaxy (MBE) on GaAs and InSb substrates with various orientations. Reflection high-energy electron diffraction (RHEED) was used for in-situ monitoring of crystalline quality during growth. Quality and surface morphology of the grown layers was assessed by x-ray diffractometry (XRD), field emmission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM). Homoepitaxial InSb layers were grown on (111)A and (111)B InSb subtrates and photodiodes were fabricated by growing thin p-Al_xIn_1-xSb barriers between n-InSb and p-InSb layers. Heteroepitaxial InSb layers were grown on semi-insulating (001) GaAs substrates without using any buffer layer. This buffer-free growth procedure speeds up the production process and eliminates the unwanted impurities at the expense of slight degradation of crystalline quality.