Potential applications of III-V nitride semiconductors

Gallium nitride and its alloys with InN and AlN have recently emerged as important semiconductor materials with applications to yellow, green: blue and ultraviolet portions of the spectrum as emitters and detectors and high Fewer temperature electronics. Blue and green nitride LEDs exhibit brightness levels and longevity well in excess of that required for outdoor applications. Combined with the available red LEDs, true full color all semiconductor displays can be attained for the first time. If used for traffic lights and illumination (pending further improvements in blue in some cases), these devices can outlast and outperform the incandescent light bulbs while saving precious energy. This material system is also intrinsically germane to short wavelength semiconductor lasers for increased data storage. Very recently, pulsed room temperature operation of 410 nm semiconductor lasers, the shortest wavelength ever from a semiconductor, have been reported. Nitrides are also conducive for high power devices/circuits, and sensors and detectors with applications in high temperature and unfriendly environments which leads to estimates that substantial weight savings can be achieved in aircraft and spacecraft. Moreover, the AlGaN alloy with bandgap above 5.5 eV shows negative electron affinity surfaces with applications to cold cathodes in general and Aat panel displays in particular. (C) 1997 Elsevier Science S.A.