GE CLUSTER FORMATION WITH MONOLAYER AND SUBMONOLAYER COVERAGES ON THEGAAS(110) SURFACE

We examine the deposition process of Ge adatoms on the GaAs(110) surfa ce. We use total energy calculations based on ab initio pseudopotentia ls constructed within the local density approximation. The equilibrium morphologies for the adatoms, and the growth pattern determined for m onolayer and submonolayer coverages, are calculated. Also, the binding energy of different sites, vibrational frequencies of adatoms on thes e sites, and the migration energy barrier along the [110BAR] direction are presented. Our theoretical model for Ge cluster formation and mor phology on the GaAs surface is consistent with recent scanning tunnell ing microscopy measurements for this surface.