GROWTH MECHANISM AND CLUSTERING PHENOMENA: THE Ge ON Si SYSTEM.

The clustering behaviour of the system Ge on Si has been investigated by ion scattering and electron microscopy. Post-deposit annealed Ge is shown to grow 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. The single clusters show Moire fringes with decreasing spacing towards their center, indicating that the elastic strain is higher at the periphery region and lower at the center region. An analogue study of clusters formed during deposition at low rates show identical features. This is consistent with an estimate of the limit for the application of the Ostwald ripening approach to the non-zero deposition rate regime.