CLUSTER DYNAMICS ON VICINAL SURFACES

We have carried out a study of the dynamics of cluster formation during epitaxial growth an recovery on vicinal surfaces. By considering all of the possible configurations for up to four-atom clusters, we have been able to elucidate the role of different island types and shapes during the various stages of growth. Inclusion of species with slow decay pathways is crucial for describing the recovery of the surface morphology, since the breakup of stable configurations is the rate-determining step for the relaxation of the surface once the incoming flux has been turned off. We find that the recovery of the surface can be divided into two stages: an initial rapid decay due to activity of atoms with one nearest neighbor, and a subsequent slower stage is coupled up to third order to the breakup of the most stable species.