A continuum model, for non-equilibrium heterogeneous elastic systems, was presented which included smooth and singular strains; as well as their coupling to free surfaces, in 2 dimensions. It included the nucleation, interaction and dynamics of dislocations. It was demonstrated that the model reproduced the Matthews-Blakeslee critical thickness for the nucleation of misfit dislocations. For misfitting hetero-epitaxial films above the critical thickness, dislocations competed with stress-induced instability of the film/vapour interface as a strain-relief mechanism. At short times, the dislocations slowed the initial instability by climbing to the film/substrate interface and partially relaxing the misfit strain.

Dislocations and Morphological Instabilities - Continuum Modelling of Misfitting Heteroepitaxial Films. M.Haataja, J.Müller, A.D.Rutenberg, M.Grant: Physical Review B, 2002, 65[16], 165414 (20pp)