Nitride-based micron-scale hexagonal pyramids array vertical light emitting diodes by N-polar wet etching.

In this work, we reported the fabrication of nitride-based hexagonal pyramids array (HPA) vertical-injection light emitting diodes (V-LEDs) by N-polar wet etching. The performance of HPA V-LEDs devices was significantly improved with 30% higher internal quantum efficiency compared with conventional roughened broad area V-LEDs. The simulated extraction efficiency by finite difference time domain method was 20% higher than typical roughened V-LEDs. The reversed leakage current of HPA V-LEDs was reduced due to better crystal quality, which was confirmed by conductive atomic force microscopy measurement. Furthermore, the efficiency droop for HPA V-LEDs were substantially alleviated.