新型电子阻挡层结构对蓝光InGaN发光二极管性能的提高

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AlGaN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。

Performance Improvement of Blue InGaN Light-emitting Diode with A Special Designed Electron-blocking Layer

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.