Dislocation glide in {110} planes in semiconductors with diamond or zinc-blende structure

The activation of the secondary a/2〈110〉{110} glide systems as observed by transmission electron microscopy in epitaxial Ge(Si) and InGaAs layers grown on comparatively highly misfitting substrates, is rationalized in terms of a mechanical equilibrium analysis that includes a frictional force on the gliding dislocations. The conditions for occurrence of further secondary glide planes, such as {113} and {100}, are outlined.