The electromigration-induced flow of islands and voids on the (001) surface was studied at the atomic scale. The basic drift mechanisms were identified by using a complete set of energy barriers for adatom hopping on the (001) surface; together with kinetic Monte Carlo simulation. The energy barriers were calculated by using the embedded-atom method and were parametrized by using a simple model. The dependence of the flow upon temperature, size of cluster, and strength of applied field was obtained. It was found that, for both islands and voids, edge diffusion was the predominant mass-transport mechanism and the rate-limiting steps were identified. For both islands and voids, the latter involved the detachment of atoms from corners and onto the adjacent edge. The energy barriers for these moves were found to be in good agreement with the activation energy for island and void drift which was obtained from an Arrhenius analysis of the simulation results. It was concluded that the results were relevant to other face-centered cubic (001) metal surfaces.

Electromigration-Induced Flow of Islands and Voids on the Cu(001) Surface. H.Mehl, O.Biham, O.Millo, M.Karimi: Physical Review B, 2000, 61[7], 4975-82