Structures of glide-set 90° partial dislocation cores in diamond cubic semiconductors

Two core reconstructions of the 90degrees partial dislocations in diamond cubic semiconductors, the so-called single- and double-period structures, are often found to be nearly degenerate in energy. This near degeneracy suggests the possibility that both core reconstructions may be present simultaneously along the same dislocation core, with the domain sizes of the competing reconstructions dependent on temperature and the local stress state. To explore this dependence, a simple statistical mechanics-based model of the dislocation core reconstructions is developed and analyzed. Predictions for the temperature-dependent structure of the dislocation core are presented. (C) 2003 Elsevier B.V. All rights reserved.