Structural and Electronic Properties of a Thin Metal-Silicide Film on Silicon Surface: A First-Principles Study

Abstract

The structural stability of metal (M) silicide (M = Co, Ni) phases and magnetic properties for the deposited one and two monolayers (ML) of M on the Si(001) surface was studied by the use of the ab initio full-potential linear muffin-tin orbital (FP-LMTO) method. The diffusion of M atoms on Si into the tetrahedral (fourfold M) sites was found to be energetically favorable. The deposited M atoms easily migrate into the bulk because the diffusion or interchange is energetically more favorable than the formation of cluster in a surface layer. The energetics for the structural stability of the "fourfold Si surface" model was compared with that of the sixfold structural model. Our results for the electronic properties of the MSi2/Si(001) surface and interface were compared with experimental and other theoretical results.