采用AlGaN/GaN阻挡层的大功率InGaN/GaN MQWs蓝光LED

High Power InGaN/GaN MQWs Blue LED with AlGaN/GaN Blocking Layers

大功率InGaN/GaN多量子阱蓝光发光二极管在大注入电流下,载流子泄漏而引起的效率下降问题是目前限制大功率发光二极管光电特性及其应用的突出问题。本文通过在p型GaN和InGaN/GaN多量子阱(MQW)有源区之间插入p型AlGaN/GaN多量子势垒(MQB)电子阻挡层,利用多量子势垒对电子的量子反射作用,有效地解决了大注入下载流子泄漏问题。与未使用多量子势垒电子阻挡层的样品相比,MQB样品的光功率和外量子效率分别提高了约80%和100%。

The external quantum efficiency drooping at high injection level is a critical problem for the application of high power InGaN/GaN multiquantum wells(MQWs)blue light emitting diodes(LEDs),which is commonly attributed to the current leakage at high injection level.The p-AlGaN/GaN multiquatum barriers were inserted as the electron blocking layers between the p-GaN and InGaN/GaN MQWs active region,which can effectively prohibit the carriers leakage because of the quantum reflection effect of MQBs at high injection level.Compared with the samples without the MQBs,the light output power and the external quantum efficiency of the samples with MQBs are improved 80% and 100%,respectively.