MOVPE-preparation of Si(111) surfaces for III–V nanowire growth

We studied the preparation of the clean Si(111) surface in H2 ambient with in situ reflection anisotropy spectroscopy and UHV-based surface science tools after contamination-free transfer. X-ray photoelectron spectroscopy confirmed complete oxide removal after high-temperature annealing. In situ RAS enabled observation of the oxide removal in dependence of process temperature. Monohydride termination was verified by Fourier transform infrared spectroscopy which agrees with a (1×1) surface reconstruction we observed by scanning tunneling microscopy and low energy electron diffraction. By atomic force microscopy analysis of the morphology, we found that wet-chemical pretreatment has an impact on the different silicon surfaces we have prepared, including homoepitaxy and termination of silicon with arsenic.