Effect of cluster size on Cu/Au(111) epitaxy

Investigations of the size effect on the epitaxy when a Cu cluster was softly deposited onto Au(111) were performed using molecular dynamics, combing the tight-binding interaction potential with electron-phonon coupling. These studies reveal that epitaxy can be obtained more easily for small clusters than for the large ones after deposition. The critical cluster size to obtain epitaxy depends strongly on the incident energy and ambient temperature. Moreover, the initial structure of the cluster is also responsible for epitaxy. Here, it is shown that the lattice distortion in the cluster-substrate interface is the most serious compared with the distortion in other layers.