The nucleation of dislocations from sharp corners acting as stress concentration sites on a silicon (100) surface was studied by a combination of atomistic and continuum modelling. Ledges of various heights, similar to those found in micro-electronic devices, were considered. Attention was focussed here on the effect of ledge height and ledge-ledge elastic interaction on the activation energy for dislocation nucleation. The activation energy decreased slightly with increasing height of the ledge and had a more pronounced non-monotonic variation with the distance between stress concentration sites. The effect of introducing a radius of curvature at the root of the ledge was also studied. It was concluded that even a small radius of curvature renders the nucleation process similar to that from a flat surface of same crystallographic orientation.

Dislocation Nucleation from Interacting Surface Corners in Silicon. Z.Li, R.C.Picu: Journal of Applied Physics, 2010, 108[3], 033522