Behavior of Ga on Si(100) as studied by scanning tunneling microscopy

Abstract
The behavior of gallium on the Si(100) surface has been studied with scanning tunneling microscopy at low metal coverages. The Ga atoms are more mobile on Si(100) than on Si(111) under the same conditions. At less than 0.1 monolayer, the Ga atoms line up in rows parallel to the Si dimerization direction with a two unit cell periodicity. At higher metal densities, these rows are organized into areas of 3×2 two-dimensional order. The relevance of these results to studies of the initial stages of growth of GaAs on Si is discussed.