Dislocation dynamics in hetero-epitaxial multilayer thin film systems was simulated for the case where threading dislocations emerging from the substrate replicated themselves into the thin film during the film growth process. In the regime where the thin film layer thickness was tens of nanometers, the strain hardening mechanism involves the glide of single threading dislocation segments in the thin film instead of by dislocation pile-ups. The evolution behavior and interactions of the dislocations were studied since these then became significant to the strain-hardening of the multilayer structure. Cross-slip of threading dislocation segments in multilayer structure was found to be more prevalent compared to a single-layered thin film. This could result in a more complex pattern of interfacial dislocations and may have a significant contribution to the interactions between threading and interfacial dislocations. The simulation was carried out using the level set method incorporating thin film growth.

Dislocation Cross-Slip in Heteroepitaxial Multilayer Films. S.S.Quek, Y.W.Zhang, Y.Xiang, D.J.Srolovitz: Acta Materialia, 2010, 58[1], 226-34