It was noted that, in some systems, a surface roughness or waviness arose which was spatially correlated with the positions of interface misfit dislocations. It was suggested here that the waviness along the surface could be the result of surface diffusion which was driven by a gradient in the chemical potential of the material along the surface. The chemical potential gradient in turn arose from the non-uniform strain field of interface misfit dislocations, as well as from unrelaxed elastic mismatch strains. Emphasis was placed here on the development of a relatively simple model, for such a system, which led to an estimate of the magnitude and profile of surface waviness under conditions of thermodynamic equilibrium after the material had responded to the chemical potential gradient by adopting a new configuration in which the stresses had been redistributed and the chemical potential was again uniform. The condition of uniform chemical potential over the final shape led to an integro-differential equation, for the equilibrium surface shape, which was solved numerically. For typical values of the system parameters, estimates of equilibrium surface roughness were obtained which could vary from less than 1% of the film thickness, up to a significant fraction of the film thickness. Although transient aspects were not studied, the characteristic time required to achieve an equilibrium configuration was estimated.

Equilibrium Surface Roughness of a Strained Epitaxial Film due to Surface Diffusion Induced by Interface Misfit Dislocations. F.Jonsdottir, L.B.Freund: Mechanics of Materials, 1995, 20, 337-49