Dislocation formation from a surface step in semiconductors: Anab initiostudy

The role of a simple surface defect, such as a step, for relaxing the stress applied to a semiconductor, has been investigated by means of large-scale first-principles calculations. Our results indicate that the step is the privileged site for initiating plasticity, with the formation and glide of 60^∘ dislocations for both tensile and compressive deformations. We have also examined the effect of surface and step termination on the plastic mechanisms.