GROWTH AND CHARACTERIZATION OF II-VI BLUE-LIGHT-EMITTING DIODES USINGSHORT-PERIOD SUPERLATTICES

We investigate the properties of II-VI short period superlattice (SPSL ) blue light-emitting diodes grown by molecular beam epitaxy. The devi ce consists of a ZnSe active layer, SPSL MgZnSSe cladding layers, and a ZnSeTe digital graded contact. The SPSL structure is made of alterna ting layers of MgSe, ZnSe, ZnS, and ZnSe. Highly ordered SPSL layer st ructures are successfully grown. Tweedlike contrast is observed in the pseudomorphic SPSL from our transmission electron microscopy analysis . The device shows high purity blue emission at 460 nm at room tempera ture with a 13 nm full width at half maximum. Operating at 14 A/cm(2), the half-intensity Lifetime is more than 13 h at room temperature wit h an external quantum efficiency of similar to 0.1%. (C) 1996 American Institute of Physics.