DISLOCATION IN THE 1/2 (110) (110) GLIDE SYSTEM IN THE DIAMOND LATTICE - DISSOCIATION BY CLIMB

The dissociation by climb of a perfect dislocation (b = (a/2) [110]) in the (a/2) [110] {110} glide system is studied by high-resolution electron microscopy in heteroepitaxial Ge layers, grown onto Si(001). The partial dislocations have Burgers vectors b = (a/4) [110]. The energy of the stacking fault gamma can be assessed from the observed dissociation width of the partial dislocations as gamma = 120 mJ/m2. The formation process of this configuration is discussed in terms of a short circuit diffusion process. A dissociation of the dislocation within the {110} glide plane could not be observed in our samples.