Various equilibrium dissociation geometries of 60º dissociated misfit dislocations in single heterostructures were considered in terms of elasticity theory. It was concluded that 60º glide misfit dislocations in strained-layer heterostructures generally dissociated into partial dislocations. Three geometries of the equilibrium dissociation configurations of these misfit dislocations with respect to the strained interface were possible; depending upon the material parameters. In some cases, the equilibrium dissociation configuration involved one partial which lay at, or near to, the strained interface while the other partial lay in the strained layer. In other cases, the equilibrium dissociation configuration was flexible with respect to the strained interface. The equilibrium dissociation width had the same value as it had in the bulk substrate material. The equilibrium dissociation configuration could also be such that one partial lay at, or near to, the strained interface while the other lay partly in the substrate. The equilibrium dissociation width was again the same as that in the bulk substrate material. The positions of the two partials, with respect to the epitaxial surface, depended upon the growth direction and the strain state (compressive or tensile). In the case of a 30º partial which led during the generation of 60º misfit dislocations, the 30º partial was further away from the epitaxial surface than was the 90º partial. In the case where the 90º partial led, the 30º partial was closer to the epitaxial surface than was the 90º partial.

Theoretical Consideration of Equilibrium Dissociation Geometries of 60º Misfit Dislocations in Single Semiconductor Heterostructures. J.Zou, D.J.H.Cockayne: Journal of Applied Physics, 1995, 77[6], 2448-53