Growth enhanced surface diffusion and elastic instability on amorphous solids

A continuum model for growth of solids is developed, considering adatom deposition, surface diffusion, and configuration dependent incorporation rate. For amorphous solids it is related to surface energy densities. The high adatom density leads to growth enhanced dynamics of (a) Mullins’ classical equation [J. Appl. Phys. {\bf 28}, 333 (1957)] without, and (b) of the Asaro-Tiller-Grinfeld-Srolovitz instability with lateral stress in the growing film. The latter mechanism is attributed to morphologies found in recent experiments.