Using reaction pathway sampling, an investigation was made of the shear stress dependences of the activation energies of shuffle-set and glide-set dislocation nucleation from a sharp corner in silicon. The gradient of the glide-set dislocation curve was lower than that of the shuffle-set dislocation, and the athermal stress of glide-set dislocation was largely higher than that of shuffle-set dislocation. As a result, the two curves had  a cross point, which means that shuffle-set dislocation was likely nucleated at high stress and low temperature and glide-set dislocation was likely nucleated at low stress and high temperature. The result clearly explained the mechanism of recent molecular dynamics on these two types of dislocation nucleation at different temperatures and stress regimes. With increased compressive stress on the slip plane, the activation energy of the shuffle-set dislocation nucleation was greatly decreased, while that of glide-set dislocation nucleation was slightly increased. That would explain why shuffle-set dislocations were found under compressive stress fields.

Reaction Pathway Analysis for Dislocation Nucleation from a Sharp Corner in Silicon: Glide Set Versus Shuffle Set. K.Shima, S.Izumi, S.Sakai: Journal of Applied Physics, 2010, 108[6], 063504