Growth mechanism and clustering phenomena: The Ge-on-Si system

The clustering behavior of Ge thin films deposited on Si has been investigated by ion scattering and electron microscopy. Post-deposit-annealed Ge is shown to cluster according to an Ostwald ripening mechanism. The cluster-volume growth is linear in time, and the cluster-size distribution is in agreement with the theoretical prediction. Cluster formation during low deposition rates is also studied. This permits an estimate of the limit for the application of the Ostwald-ripening approach to the nonzero deposition-rate regime.