H01S 5/3214

Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures {characterised by special cladding layers, e.g. details on band-discontinuities comprising materials from other groups of the periodic system than the materials of the active layer, e.g. ZnSe claddings and GaAs active layer}