Strain relaxation in highly mismatched hexagonal heterosystems

In this work, the formation of interfacial misfit dislocations (IMD) along with the elastic strain relaxation have been considered for the case of highly lattice mismatched heterosystems with m:n matched interfaces. It was shown that for the growth stage anticipating the coalescence, the strain relaxation in the nuclei can be described analytically by means of the unified mechanical/ thermodynamical (Kern's/IMD) model using two key parameters-the residual strain in the nuclei and their critical thickness. The general conditions for the rapid coalescence in such systems have been formulated in terms of the macroscopic system parameters: coalescence thickness<mean system length<critical size of the nucleus.