Insight into the local density of states at Si sites at the submonolayer Si/Ge(001)-2 x 1 interface from Si KLV Auger spectroscopy

An analysis of the differences observed between the Si KLV Auger spectra of the Si/Ge(001)-2 x 1 interface and pure Si indicates that the electronic structure of the interface is characterized by a reduction in the local p DOS at the Si sites and a transfer of p valence charge from Si to Ge. As a result, the screening of core-ionized Si sites at the interface is significantly shifted towards s screening compared with the situation for pure Si. It is possible that there is an increase in the on-site electron correlation energy, U(P), for Si sites at the interface as compared with pure Si.