S. Kozyukhin, R. Golovchak, A. Kovalskiy, O. Shpotyuk, H. Jain.
Физика и техника полупроводников, vol. 45, No. 4, 2011, p. 433-436.
High-resolution X-ray photoelectron spectroscopy (XPS) is used to study regularities in the formation of valence band electronic structure in binary AsxSe100−x, AsxS100−x, GexSe100−x and GexS100−x chalcogenide vitreous semiconductors. It is shown that the highest occupied energetic states in the valence band of these materials are formed by lone pair electrons of chalcogen atoms, which play dominant role in the formation of valence band electronic structure of chalcogen-rich glasses. A well-expressed contribution from chalcogen bonding p electrons and more deep s orbitals are also recorded in the experimental valence band XPS spectra. Compositional dependences of the observed bands are qualitatively analyzed from structural and compositional points of view.