Molecular dynamics simulations were made of silicon nanostructures submitted to various stresses and temperatures. For a given stress orientation, a transition in the onset of silicon plasticity was revealed depending on the temperature and stress magnitude. At high temperature and low stress, partial dislocation loops were nucleated in the {111} glide-set planes. But at low temperature and very high stress, perfect dislocation loops were formed in the other set of {111} planes called shuffle. This result confirmed by three different classical potentials suggested that plasticity in silicon nanostructures could be controlled by dislocation nucleation.

Evidence of Two Plastic Regimes Controlled by Dislocation Nucleation in Silicon Nanostructures. J.Godet, P.Hirel, S.Brochard, L.Pizzagalli: Journal of Applied Physics, 2009, 105[2], 026104