BLUE-GREEN II-VI LASER-DIODES

The first blue-green laser diodes were demonstrated in our laboratories in early April 1991 using wide band gap II-VI semiconductors. Since then, devices with emission wavelengths from 508 to 535 nm have been obtained in the pulsed mode at room temperature with threshold current densities about 1000 A/cm2. Continuous wave devices have also been operated at 80 K emitting more than 3 mW/facet. These diodes are separate confinement devices with single CdxZn1-xSe strained quantum wells within ZnSe p-n junctions. Optical confinement is accomplished by surrounding the ZnSe guide with ZnS0.07Se0.93 cladding layers. Characteristics of these devices and the issues standing in the way of commercializing II-VI LEDs and diode lasers are discussed.