We demonstrate the optoelectrical characteristics of thick well short-period InGaN/GaN multiple-quantum-well (MQW) light-emitting diodes (LEDs) with H2 in GaN barrier spacer layer. Introducing ramped H2 in the GaN barrier spacer layer creates a wide range of severe well thickness variation randomly distributed in the thick InGaN well. The thickness-fluctuated InGaN well would effectively increase the carrier concentration in the region of the thick InGaN well region during the current injection. Moreover, the ramped H2 in GaN barrier spacer layer would improve the interface and crystal quality of thick well short-period InGaN/GaN MQWs LEDs. Therefore, compared with traditional long-period InGaN/GaN MQW LEDs, thick well short-period InGaN/GaN MQW LEDs with fluctuated InGaN well thickness enhance output power (25.6% at 20 mA) and improve efficiency droop from 55.0% to 36.7%.
© 2012 IEEEPDF Article