Nitride-based light-emitting diodes with p-AlInGaN surface layers prepared at various temperatures

The authors have prepared bulk p-AlInGaN layers and light-emitting diodes (LEDs) with p-AlInGaN surface layers by metal organic chemical vapor deposition. They found that the surfaces of the LEDs with p-AlInGaN layers are rough with high density of hexagonal pits. They also found that the pit width and the pit density depend on the growth temperature of the p-AlInGaN layer. Furthermore, it is found that a 62% enhancement in output intensity can be achieved from the LED with an 820 °C p-AlInGaN cap layer without increasing the LED operation voltage.