XPS study of single crystal Ge-Si alloys

Abstract The binding energies of the Ge 3d and Si 2p core electrons in single crystal GeSi alloys were studied by x-ray photoelectron spectroscopy (XPS). It was found that up to the instrumental resolution neither the energy position nor the line shapes change as the alloy composition is varied. This in turn puts a limit on the electronegativity of Ge and Si and consequently on the electron charge transfer between the two atoms in the alloy. The results are discussed and compared to similar measurements on sputtered grown amorphous GeSi alloys.