Electronic and geometric structures of the Au–Si(1 0 0) surface observed by photoemission spectroscopy and LEED

Abstract

We have investigated the electronic and geometric structures of the Au–Si(1 0 0) surface as a function of annealing temperature by means of Si 2p and Au 4f core-level photoemission spectroscopy and low energy electron diffraction (LEED). The 1 × 1, c(8 × 2) and 5 × 3.2 structures were obtained by annealing the Au–Si(1 0 0) surface at 250, 630 and 750 °C, respectively. From the intensity ratio of the Au 4f to Si 2p spectra, it was found that the chemical composition was almost identical for the 1 × 1, c(8 × 2) and 5 × 3.2 structures. On the other hand, changes in the peak position and shape of the Si 2p and Au 4f spectra were observed when the 1 × 1/ c(8 × 2) structure changed to the c(8 × 2)/5 × 3.2 structure. The spectral changes indicate that there are several components due to different Au–Si interactions. Based on the results of the Si 2p and Au 4f core-level photoemission analysis and LEED patterns, we discuss the electronic and geometric structures of the Au–Si(1 0 0) surface.