On the hole accelerator for Ⅲ-nitride light-emitting diodes

摘要

In this work, we systematically conduct parametric studies revealing the sensitivity of the hole injection on the hole accelerator (a hole accelerator is made of the polarization mismatched p-electron blocking layer (EBL)/p-GaN/p-Al_xGa_(1-x)N heterojunction) with different designs, including the AlN composition in the p-Al_xGa_(1-x)N layer, and the thickness for the p-GaN layer and the p-Al_xGa_(1-x)N layer. According to our findings, the energy that the holes obtain does not monotonically increase as the AlN incorporation in the p-Al_xGa_(1-x)N layer increases. Meanwhile, with p-GaN layer or p-Al_xGa_(1-x)N layer thickening, the energy that the holes gain increases and then reaches a saturation level. Thus, the hole injection efficiency and the device efficiency are very sensitive to the p-EBL/p-GaN/p-Al_xGa_(1-x)N design, and the hole accelerator can effectively increase the hole injection if properly designed.