Experimental and theoretical study of the electronic properties Of COSi2 and NiSi2

Electronic structure of Co and Ni silicides were studied by means of the spectral properties of XPS high-resolution measurements together with theoretical calculations using crystal orbital overlap population (COOP) analysis. Calculations were carried out for CoSi2 and NiSi2 microstructures. Analysis from calculations shows that hybridization is stronger in Co disilicide than in Ni disilicide. Close to the Fermi level, we noticed that for the Co disilicide there is a small distribution (bonding and antibonding) to the total COOP, while the contribution from the Ni disilicide is null. XPS analysis of sample under study gives evidence about the covalent bonding when the chemical shifts for the Co 2p(3/2), Ni 2p(3/2) and Si 2p transitions are analyzed in the depth-profile mode. (C) 2004 Published by Elsevier B.V.