Arsenic overlayer on Si(111): Removal of surface reconstruction

Abstract
The complex reconstruction characteristic of annealed Si(111) surfaces is removed by the interaction of As with the clean Si(111) 7×7 surface. Surface-sensitive core-level spectroscopy measurements of the Si(111):As 1×1 surface reveal a well-ordered surface with threefold-coordinated As atoms replacing the Si atoms in the outermost layer. The absence of dangling bonds in this structure leads to an unreconstructed surface which is highly resistant to contamination.