Island formation in superlattice structures having a moderate defect density was investigated for a sub-monolayer range of CdSe nominal thicknesses. As well as the spontaneous formation of CdSe-enriched islands in defect-free regions, the presence of dislocations which crossed the superlattice caused emergence of defect-attached islands. The location of islands near to the interceptions of CdSe sheets with dislocations produced a staircase ordering of the islands in neighbouring superlattice layers. Such a mutual alignment of the CdSe-enriched islands resulted in modified optical properties of the defect-containing structures. The density and type of defects which promoted the laterally inhomogeneous incorporation of Cd were controlled, in general, by the initial stage of molecular beam epitaxial growth and lattice mismatch between ZnS(Be)Se cladding layers and a GaAs substrate.

Defect-Induced Island Formation in CdSe/ZnSe Structures. T.V.Shubina, A.A.Sitnikova, V.A.Solovev, A.A.Toropov, I.V.Sedova, S.V.Ivanov, M.Keim, A.Waag, G.Landwehr: Journal of Crystal Growth, 2000, 214-215, 727-31