Absorption of Li on the Si(100)2x1 surface studied with high-resolution core-level spectroscopy

The adsorption of Li on the Si(100) surface has been studied over a wide coverage range with high-resolution core-level spectroscopy. The dimer structure of the clean surface was preserved up to a coverage corresponding to Delta phi = -1.8 eV. Above this coverage intermixing and silicide growth starts. It is shown that the silicide reaction is controlled by the amount of Li present on the surface. Up to four new components shifted equidistantly by similar to 0.44 eV to lower binding energies appeared in the Si 2p spectra upon the silicide formation. The Li 1s level displayed several components, indicating the presence of increasingly Li-rich phases at high coverges.