The dislocation densities in molecular beam epitaxially grown ZnSe/GaAs/GaAs heterostructures, with various different epilayer thicknesses, were studied by examining the full-widths at half-maximum of high-resolution X-ray diffraction reflection peaks. Three regimes of dislocation generation were observed. The first regime existed in samples of sub-critical thickness, where only stacking faults were present and their formation depended upon the preparation conditions of the substrate and the initial growth conditions. The second regime existed in samples with a layer thickness that was greater than the critical thickness, but thinner than a threshold thickness of about 0.3μ. Here, a large amount of misfit and threading dislocations were generated. The third regime existed at layer thicknesses greater than 0.3μ. Here, the formation of dislocations was substantially slowed, and their density obeyed a reciprocal dependence on thickness; as predicted by the glide model.

Dislocation densities in molecular beam epitaxially grown ZnSe epitaxial layers on GaAs M.E.Constantino, M.A.Vidal, B.Salazar-Hernández, H.Navarro-Contreras, M.López-López, M.Meléndez, I.Hernández-Calderon: Journal of Crystal Growth, 1998, 194[3-4], 301-8