Wide-Bandgap II-VI Heterostructures for Blue/Green Optical Sources: Key Materials Issues

Substantial advances have been realized in the quest to achieve blu e/green light-emitting devices and injection lasers based on wide-bandgap II-VI semiconductor materials. The lasers operate continuously at room tem­ peratur e and emit a signifi cant amount of power with wavelengths ranging from 463 to 51 4 nm (depending on the actual structure). The various laser structures are composed of (Zn,Mg)(Se,S) and Zn(Se,S) cladding layers with (Zn,Cd)Se quantum wells and possess a graded ohmic contact con­ sisting of Au metal on a pseudo-alloy of Zn(Se, Te). In addition to describ­ ing the advantages and disadvantages offered by various epitaxial growth