Published online by Cambridge University Press: 15 February 2011
The strain induced by the thermal mismatch in Pbl−xSnxSe and other IV–VI compound layers on Si(111)-substrates relaxes by glide of dislocations in the main <110> {001}-glide system. The glide planes are arranged with 3-fold symmetry and inclined to the (111)-surface. Despite a high threading dislocation density (> 107 cm−2) in these heavily lattice mismatched structures, the misfit dislocations move easily even at cryogenic temperatures and after many temperature cycles between RT and 77K. The cumulative plastic deformation after these cycles is up to 500%! Despite a pronounced deformation hardening occurs, the structural quality of the layer is only slightly adversely affected as regards additional threading dislocations created. The interaction probability between these dislocations is estimated to be about 10−5.