Microstructure study of a degraded pseudomorphic separate confinement heterostructure blue-green laser diode

The microstructure of a degraded II-VI blue-green laser diode based on the ZnCdSe/ZnSSe/ ZnMgSSe pseudomorphic separate confinement heterostructure has been examined by transmission electron microscopy. Triangular nonluminescent dark defects observed in the laser stripe region by electroluminescence microscopy have been identified to be dislocation networks developed at the quantum-well region. The dislocation networks have been observed to be nucleated at threading dislocations originating from pairs of V-shaped stacking faults which are nucleated at or near the II-VI/GaAs interface and extending into the n-ZnMgSSe lower cladding layer.