Computer simulation of the surface topology of (001) silicon resulting from the termination of edge dislocations with Burgers vectors parallel to the surface

The Stillinger-Weber interatomic potential for silicon was used to simulate the atomic arrangement at the emergence points of a/2〈110〉 perfect edge dislocations at a free surface. Results indicate step heights are comparable in magnitude vectors parallel to the surface can produced steps at the surface. The resulting step heights are comparable in magnitude with the steps which would be created if these dislocations were dissociated into Shockley partials. As a result, step source activation from these dislocations is possible without dissociation. The origin of the steps can be rationalized in terms of the Poisson expansion and contraction owing to relaxation of the compressive and tensile stress fields of the edge dislocations at a free surface.