AlN/蓝宝石衬底上AlGaN-UV-LEDs光学性能改善研究

Study of improvement in optical property for AlGaN-UV-LEDs based on AlN/sapphire template

通过有机金属化学气相沉积法在AlN/蓝宝石衬底上生长AlGaN基多量子阱结构的发光二极管(LEDs),其对应的发光峰值波长为264nm(UV-C区)。通过在活性区域和p型外延层之间插入1nm厚的本征AlN层(起到电子挡层的作用),可以清楚地观测到有效抑制位于320nm附件的寄生发光峰,推测这是电子溢出或Mg扩散所致。此外,发现了通过改变外延层的结构可以使LEDs的输出功率增长20倍以上。

Using metal organic chemical vapour deposition,AlGaN-based multiple-quantum-well light-emitting diodes（LEDs）with peak emission at UV-C region of 264 nm have been successfully gown on AlN/sapphire template.It has been clearly observed that a subband emission around 320 nm can be drastically reduced by inserting a thin 1nm-thick i-AlN interlayer（as a function of electron blocking layer）between the active region and p-type epitaxy layers.Which is presumably a result of the suppression of electron overflow or Mg diffusion.In addition,it has been found that the output power in LEDs can be 20 times more than that by changing the layer construction.