Current status and future prospects of ZnSe-based light-emitting devices

Device lifetime has been improved to over 100 h by reducing dark-spot density (DSD) to less than 3×10 ³ cm ^-2. The lifetime of II-VI laser diodes is no longer limited by a rapid degradation but by gradual degradation due to microscopic point defects. Lifetime has been significantly improved up to ∼500 h at 20°C under CW operation with LDs grown in Se-rich conditions for the active layer. If we know the growth-condition dependence of degradation behaviors, it may be possible to improve the reliability of ZnSe-based LDs. ZnSe-based LDs are being developed for applications such as display systems and printing systems utilizing their pure green emission.