X-Ray Photoelectron and Anger Electron Spectroscopic Studies of Chemical Shifts in Amorphous Ge–Se System

The chemical shifts of the Ge 3d, 3p 3/2,1/2 and Se 3d, 3p 3/2,1/2 photoelectron lines were measured for the amorphous Ge–Se system and those of the Ge photoelectron lines are corrected for Auger parameter shifts. According to the valence shell potential model, the ratio of the chemical shift in the amorphous Ge–Se system to that in stoichiometric GeSe 2 can be approximated by the ratio of the Ge–Se bond number in the Ge–Se system to that in GeSe 2 . The chemical shift ratios evaluated from the experimental results reveal bond structures at non-stoichiometric compositions. In the excess-Ge range, GeSe is composed of atomic clusters of three-fold co-ordinated Ge and Se atoms, and Ge 2 Se 3 contains atomic clusters of Se 3 Ge–GeSe 3 units. In the excess-Se range, GeSe 3 includes GeSe 4 tetrahedral units, and Se–Se chains and/or Se 8 rings.