Investigations of the SiO2/Si interface. I. Oxidation of a clean Si(100) surface using photoemission spectroscopy with synchrotron radiation

Abstract

The surface oxidation process of Si(100), and the distribution of intermediary oxidation states at the SiO₂/Si interface have been extensively studied by high resolution (ΔE2/Si interface for three intermediary states, Si³⁺, Si²⁺, and Si¹⁺ (SiO_x), is strongly dependent on SiO₂ layer thickness. In particular, the proportion of Si³⁺ increases with the formation of the 0∼1 nm thick SiO₂ layer. However, the three intermediary components at the interface are distributed with ratios of Si³⁺:Si²⁺:Si¹⁺=7:2.5:1 in the oxidation stage where a SiO₂ layer is formed over 1 nm.