新型电子阻挡层结构对蓝光InGaN发光二极管性能的提高

摘要

分别对3种不种电子阻挡层的蓝光AlGaN LED进行数值模拟研究.3种阻挡层结构分别为传统Al-GaN电子阻挡层,AlGaN-GaN-AlGaN电子阻挡层和Al组分渐变的AlGaN-GaN-AlGaN电子阻挡层.此外对这对三种器件的活性区的载流子浓度、能带图、静电场和内量子效率进行比较和分析.研究结果表明,相较于传统AlGaN和AlGaN-GaN-AlGaN两种电子阻挡层的LED,具有Al组分渐变的AlGaN-GaN-AlGaN电子阻挡层结构的LED具有较高的空穴注入效率、较低的电子外溢现象和较小的静电场(活性区).同时,具有Al组分渐变的AlGaN-GaN-AlGaN电子阻挡层结构的LED的efficiency droop现象也得到一定的缓解.%Three kinds of electron-blocking layer (EBL) AlGaN based LED were compared numerically.They are conventional AlGaN EBL,AlGaN-GaN-AlGaN (AGA) and gradual Al composition AlGaN-GaN-AlGaN (GAGA)EBL.Their porfermance were analyzed involved carrier concentration in the active region,energy band diagram,electrostatic field and internal quantum efficiency (IQE).The results indicate that the LED with an GAGA EBL exhibits a better hole injection efficiency,a more peaceable efficiency droop,a lower electron leakage,and a smaller electrostatic field than the LED with a conventional AlGaN EBL or with an AGA EBL.