Azimuthal rotation in epitaxial CdSe/Ge /111/ heterojunctions

Doubly thinned specimens of CdSe films grown by focused electron beam evaporation in a vacuum were examined by transmission electron microscope in order to study the epitaxial orientation relation between the films and the (111) Ge substrates. Some micrographs showed what might be misfit dislocations, although a Burgers vector determination on these possible misfit dislocations was not possible. An analysis was performed to examine quantitatively the consequences of the hypothesis that the CdSe/Ge (111) interface contains a network of 60-deg misfit dislocations with their Burgers vectors in the interface. This hypothesis was found to be able to account self-consistently for both the change in lattice parameter and the azimuthal rotation across the interface.