反对称n-AlGaN层对GaN基双蓝光波长发光二极管性能的影响

采用数值分析方法对在InGaN/GaN混合多量子阱活性层和n-GaN之间引入n-AlGaN层的GaN基双蓝光波长发光二极管进行模拟分析.结果发现,与传统的具有p-AlGaN电子阻挡层的双蓝光波长发光二极管相比,这种反对称n-AlGaN层能有效改善电子和空穴在混合多量子阱活性层中的分布均匀性及减少电子溢出,实现电子空穴在各个量子阱中的平衡辐射,从而减弱了双蓝光波长发光二极管的效率衰减.此外,通过改变Al组分可以提高双蓝光波长发光二极管发射光谱的稳定性:当Al组分为0.16时,双蓝光波长发光二极管的光谱在小电流下比较稳定,而Al组分为0.12时,光谱在大电流下比较稳定.

Effect of an asymmetry n-AlGaN layer on performance of dual-blue wavelength light-emitting diodes

The effect of an n-type AlGaN layer on the physical properties of dual-wavelength light-emitting diode (LED) is investigated numerically. The simulation results show that compared with the conventional p-type AlGaN electron-blocking layer (EBL), the n-type AlGaN layer can improve the distribution of electrons and holes more uniformly and realize the radiation balance between electrons and holes in the quantum wells, and further reduce the efficiency dro of dual-blue wavelength LED at high current. In addition, the spontaneous emission rate of two kinds of quantum wells can be adjusted through the control of Al composition. It can be found from the results that the emission spectrum of dual-blue wavelength LED is more stable at low current with an Al composition of 0.16, while the emission spectrum is more stable at high current with an Al composition of 0.12.