AlGaN single-quantum-well light-emitting diodes with emission at 285 nm

We report on AlGaN single-quantum-well light-emitting diodes (LEDs) on sapphire with peak emission at 285 nm. A study is presented to identify the key material parameters controlling the device quantum efficiency. At room temperature, for a 200 mumx200 mum square geometry mesa type device, we obtain a power as high as 0.25 mW for 650 mA pulsed pumping. The LEDs show significantly higher output powers at temperatures below 100 K. (C) 2002 American Institute of Physics.