Electronic structure of Ni and other transition-metal silicide overlayers on Si

摘要: The electronic structure of Ni overlayers on Si (111) has been calculated by the tight-binding method for various possible bonding geometries. Surface EXAFS suggests nickel exists at six- or sevenfold-coordinated, Ni6 Ni7, sites buried between topmost layers Si. authors results favour geometry which EF lies in lower gap, as observed, while Ni7 configuration appears to be less stable. A general model other transition-metal is developed. Co5 CoSi2:Si(111) interfaces rationalised and an interstitial threefold coordination suggested Co monolayers account photoemission data.