Epitaxial growth of CuInS2 on sulphur terminated Si(111)

We demonstrate the direct heteroepitaxial growth of the chalcopyrite semiconductor CuInS2 on silicon (111) substrates by means of three-source molecular beam epitaxy. The pretreatment of the silicon wafers includes sulphur termination which leads to a new surface structure defining the starting condition for successful epitaxy. All stages of the growth process were controlled in situ using Auger electron spectroscopy and low energy electron diffraction. Furthermore, the epitaxial layers were characterized by means of x-ray diffraction methods and by Rutherford backscattering spectrometry including channeling. X-ray rocking curves showed a typical width of 0.2° while the minimum yield due to the channeling effect was found to be 56%.