Fernando A. Ponce

Arizona State University, Tempe, Arizona (formerly at Xerox PARC)

The Nitride-Semiconductor Revolution in Lighting Technologies" Nitride semiconductor thin films (GaN, InN, AlN) have recently achieved light emitting efficiencies that exceed those of incandescent lamps (by about an order of magnitude) and fluorescent lamps (by a factor of two). With longer lifetimes and continuously decreasing production costs, they are poised for applications such as interior lighting, signals and flat panel displays. Laser diodes operating in the blue/violet region are now commercially available and are expected to be utilized in high density optical recording applications. These recent developments signal a revolution in lighting technologies based on the nitride semiconductors. The physical properties of these materials are quite different from other semiconductors. Fundamental understanding of these materials is far from accomplished. Many challenges remain, in particular in the production of ternary (AlGaN and InGaN) and quaternary (GaInAlN) alloys, that will allow the fabrication of near-monochromatic LEDs and laser diodes spanning the full range of the visible spectrum and into the ultraviolet range.