Dislocation patterns in strained layers from sources on parallel glide planes

The interaction of dislocations on parallel glide planes in a strained epitaxial layer is investigated nu-merically. It is found that if two dislocations approach closely enough they will form an immobile bound complex. If a third dislocation now comes near such a complex: it will knock one of the partners forward and in turn bind with the survivor. The repetitive action of this simple process leads to the growth of elaborate network structures in the substrate. The network geometry predicted by the calculation is remarkably similar to previously unexplained dislocation structures observed in transmission electron microscopy images.