Si K and Co L 3 XANES study of thin-film CoSi 2

Abstract

X-ray absorption near edge structure (XANES) spectra of thin-film CoSi 2 were measured at the Si K- and Co L 3-edge. The Si K-edge spectrum for CoSi 2 showed a dramatic reduction of intensity in the first broad feature accompanied by an increase in intensity of a peaked feature at higher energies when compared to the spectrum for crystalline Si. We attribute these two features to the Si 1s photoelectron excitations to a broad Si 3p nonbonding band and a relatively narrow band of hybridized Si p - Co 3d antibonding states, respectively. The Co L 3-edge white line spectrum for CoSi 2 reveals three distinct features which can be attributed to excitations to the unoccupied Co 3d nonbonding states and hybridized antibonding Co (3d, 4s) - Si p states.