STUDIES ON REACTION PROCESSES OF HYDROGEN AND OXYGEN-ATOMS WITH H2O-ADSORBED SI(100) SURFACES BY HIGH-RESOLUTION ELECTRON-ENERGY-LOSS SPECTROSCOPY

Surface-reactions of H2O-adsorbed Si(100) with atomic hydrogen and oxy gen have been examined by high-resolution electron energy loss spectro scopy (HREELS). The surface with saturated coverage of H2O is terminat ed by H and OH species and the sticking probability of H2O is estimate d to be 0.9. This surface is stable for the adsorption of molecular ox ygen at room temperature. The presence of dissociation sites of oxygen molecules such as dangling bonds is considered to be essential to the oxidation of Si(100) surfaces. By the reaction of H2O-adsorbed Si(100 ) with atomic hydrogen, the uptake of oxygen atoms of Si-OH bonds into sites of Si back bonds occurs even at room temperature.