ELECTRONIC PROPERTIES OF THE SINGLE-DOMAIN LI/SI(001) SURFACE

Abstract

We report surface electronic band structures of the single-domain Li-adsorbed Si(001) surface investigated by using synchrotron uv radiation. The spectral changes observed for the first two Li-induced ordered structures, a (2 x 2)-Li and a (2 x 1)-Li, suggest that these surfaces consist of asymmetric dimers as the basic building ingredients for the structures and that Li adatoms locate primarily at or near the up-Si atoms of the asymmetric dimers. Results of the line-shape analysis of Si 2p core level shifts as a function of the Li coverage support the asymmetric dimer models for the first two ordered structures and account for the rigid shifts in the surface bands.