Nitride-based LEDs with 800/spl deg/C grown p-AlInGaN-GaN double-cap layers

GaN-based light-emitting diodes (LEDs) with various p-cap layers were prepared. It was found that surface morphologies of the LEDs with 800/spl deg/C grown cap layers were rough due to the low lateral growth rate of GaN. It was also found that 20-mA forward voltage of the LED with 800/spl deg/C grown p-AlInGaN-GaN double-cap layer was only 3.05 V. Furthermore, it was found that we could achieve a high output power and a long lifetime by using the 800/spl deg/C grown p-AlInGaN-GaN double-cap layer.