Morphology and composition of Au films on Si(100)

Spot profile analysis low-energy electron diffraction, low-energy ion scattering and Auger electron spectroscopy were employed to study the morphology and composition of Au films on Si(100). After annealing, two distinct surface reconstructions were observed: a two-domain c(8×2) phase and a four-domain incommensurate (5×3.2)R5.7° phase. During the transition from the c(8×2) to the (5×3.2)R5.7° phase, the subsurface composition changes drastically from Au-rich to Si-rich, whereas the outermost layer composition remains almost constant (about 65 at.% Au). Detailed information concerning the domain structure for the two phases is subtracted from the profiles of the LEED spots.