INVESTIGATION OF NATIVE-OXIDE GROWTH ON HF-TREATED SI(111) SURFACES BY MEASURING THE SURFACE-STATE DISTRIBUTION

The evaluation of the surface state distribution of differently HF-tre ated Si(111) surfaces during the native-oxide growth in air is investi gated by the large-signal field-modulated photovoltage technique. The surface state distribution consisting of intrinsic and extrinsic Si da ngling bond defects is directly related to the state of oxidation of t he Si surface. It is shown that the kind of HF treatment strongly infl uences the concentration of extrinsic defects with a lower state of ox idation. Special HF preparations for H termination of the Si(111) surf ace result in a nearly intrinsic surface state distribution. During th e oxidation process three typical phases can be distinguished each cha racterized by specific defect structures. It was found that native-oxi de growth is highly sensitive to the concentration of extrinsic defect s directly after HF treatment.