Periodic Faceting Of Au(4,3,3) Observed By Scanning-Tunneling-Microscopy
Résumé
The Au(4,3,3) surface, vicinal to Au(1,1,1), has been studied by scanning tunneling microscopy in ultra high vacuum. It is thermally unstable towards faceting. For annealing temperatures ranging from 700 K to 1000 K, the stable state of the faceted surface is found to be a periodic succession of (1,1,1) and (7,5,5) facets. The superperiod is about 110 Angstrom and the length of the close-packed facet is about 40 Angstrom. The occurence of the (7,5,5) facet is discussed in correlation with previous equilibrium shape observations. A model to qualitatively account for the periodic formation of facets is proposed.