Strong temperature dependence of the initial oxide growth on the Si(111)7 × 7 surface

Temperature dependence of oxide growth kinetics on the Si(111)7×7 surface has been investigated by ultraviolet photoelectron spectroscopy. The amount of adsorbed oxygen on the Si surface during oxidation can be obtained from the O 2p spectra, which showed that the amount of oxygen increased with temperature below 600°C. It was found that the results cannot be described by the dual-oxide-species model for Langmuir-type adsorption in which adsorbed oxygen hardly moves on the surface. Therefore, we propose a new reaction model in which the migration and agglomeration of metastable oxygen on the surface should be considered. By studying the results of work function, we concluded that more adsorbed oxygen on the surface may incorporate into the back bond and a larger amount of defects can be generated at the Si/SiO₂ interface at higher temperature.