Intrinsic interface states and defect states for Si/NiSi2(111)

Abstract

The intrinsic interface states and the states associated with interfacial vacancies have been calculated for the type A Si/NiSi2(111) interface. A prominent band of intrinsic interface states is predicted near and below the Si valence band maximum, Ev, dispersing downward from an energy in the Si band gap to an energy about 1 eV below Ev. This band should be observable in photoemission experiments. Our calculation for the interfacial Si vacancy on the NiSi2 side of the interface yields a level, a few tenths of an electron volt above the valence band edge, that can explain observed Schottky barriers at Si/NiSi2(111) interfaces.