Mechanism for island formation during low-temperature growth on (100) surfaces of fcc metals.

Abstract

We propose a mechanism for island formation during growth on (100) surfaces of fcc metals in the absence of both thermal and nonthermal mobility of isolated adatoms: the rearrangement of atoms in islands by local diffusion processes. By means of kinetic Monte Carlo simulations we investigate the influence of these diffusion processes on the growth properties. For all these allowed rearrangement processes one single hopping rate H was chosen. For H smaller than the deposition rate R the influence of the diffusion is negligible, in the sense that the surface morphology is hardly distinguishable from the case H=0. For larger values of H/R island formation is observed, with an average island separation of 7--8 interatomic distances, in reasonable agreement with experiments. \textcopyright{} 1996 The American Physical Society.