Electroluminescence topographic and transmission electron microscopic structural studies were made of the non-luminescent areas which were developed by current injection into alloy-based II-VI blue-light emitting diodes. The non-radiative regions, which spread out in <100> directions during current injection, consisted of a high density of dislocation dipoles and dislocation loops. The sources of these defects were preexisting stacking faults which originated at the substrate/epilayer interface. The dipoles themselves were aligned along both of the <110> directions which lay in the {111} plane. Their Burgers vectors were of the type, (a/2)<011>, and were inclined at 45º to the (001) junction plane.

S.Tomiya, E.Morita, M.Ukita, H.Okuyama, S.Itoh, K.Nakano, A.Ishibashi: Applied Physics Letters, 1995, 66[10], 1208-10