INSITU PREPARATION OF HYDROGEN-TERMINATED SILICON SINGLE-CRYSTAL SURFACES

We present a study of electrochemically treated n-doped Si(111) and Si(100) surfaces using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS) and low energy electron diffraction (LEED). The conditioning of the samples was carried out in a combined electrochemistry-ultrahigh vacuum surface analysis system resulting in an unusually low contamination by hydrocarbons. A comparision of the UP spectra with the spectra of Si hydrogenated in ultrahigh vacuum experiments suggests hydrogen-covered surfaces for (111)-oriented samples. Si(100) surfaces exhibit adsorbed residual oxide and fluoride. Based on theoretical results the existence of SiH and Si:SiH3 surface complexes is discussed.