Electronic and atomic structure of Si(111) Al, Ag, and Ni metal overlayer induced surface reconstructions

Abstract

The electronic structure of the ordered metal overlayers Si(111) √3× √3: Al and √3×√3: Ag and Si(111) √19×√19: Ni prepared from Si(111)7×7 surfaces has been studied with angle-resolved photoelectron spectroscopy. On all these surfaces we find dangling bond derived bands which for Al and Ag overlayers have a dispersion of 0.4 eV. We also report a new Si(111) √7×√7: Al structure at ?0.5 monolayer coverage of Al. A new structural model for the √19×√19: Ni surface is proposed.