Morphology and composition of Au films on Si(100)

Spot profile analysis low-energy electron diffraction, low-energy ion scatt ering and Auger electron spectroscopy were employed to study the morphology and composition of Au films on Si(100). After annealing, two distinct surf ace reconstructions were observed: a two-domain c(8 x 2) phase and a four-d omain incommensurate (5 x 3.2)R5.7 degrees phase. During the transition fro m the c(8 x 2) to the (5 x 3.2)R5.7 degrees phase, the subsurface compositi on changes drastically from Au-rich to Si-rich, whereas the outermost layer composition remains almost constant (about 65 at.% Au). Detailed informati on concerning the domain structure for the two phases is subtracted from th e profiles of the LEED spots. (C) 1999 Elsevier Science B.V. All rights res erved.