Electronic structure of Au-Si(1Â 0Â 0) interface as a function of Au coverage

We have investigated the Au-Si(1 0 0) interface as a function of the Au coverage by means of the valence band and Au 4f core-level photoemission spectroscopy. At the initial stage of the Au deposition, deposited Au atoms are close to the atomic Au. With increasing the Au coverage, it is considered that the Au silicide is formed by the influence of the substrate Si atoms. From the relative intensity ratio of the Au 4f core-level spectrum to the Si 2p core-level spectrum, the appearance of the 3D islands was suggested at more than 12 ML. This means that the Au deposited surface is not homogeneous. In addition, it was found that there are two chemically different Au silicide components from the curve fitting analysis of the Au 4f core-level spectrum at the higher Au coverage.