In this work, we numerically investigate the N-polar AlGaN-based deep ultraviolet light-emitting diodes (DUV LEDs) over the Ga-polar DUV LEDs. The light output power has increased from 7.1 mW of Ga-polar DUV LED to 18.8 mW of N-polar DUV LED at 60 mA, and the wall-plug efficiency (WPE) of N-polar DUV LED is boosted by 104% at 60 mA with the same structure of Ga-polar conventional DUV LED. Furthermore, the higher operation voltage of N-polar DUV LED induced by the large energy difference between the p-type interlayer and the p-GaN hole supplier is noted. To reduce the operation voltage of N-polar DUV LED, the structure with a staircase-like p-type interlayer is proposed. The incorporation of staircase-like aluminum composition p-type interlayer mitigates the large potential barrier for holes injection, and the operation voltage is comparable to the Ga-polar DUV LED. The reduced operation voltage further promotes the WPE of N-polar DUV LEDs. Thus, combined with the promoted electron blocking ability and the mitigated potential barrier for holes of N-polar DUV LED, the greatly enhanced WPE is as high as 4.9% at 60 mA, which is 2.88 times higher than the Ga-polar DUV LED.

中文翻译：

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大幅提高 N 极性 AlGaN 基深紫外发光二极管的插壁效率

在这项工作中，我们在 Ga 极性 DUV LED 上对 N 极性 AlGaN 基深紫外发光二极管 (DUV LED) 进行了数值研究。光输出功率从 Ga 极性 DUV LED 的 7.1 mW 增加到 60 mA 时 N 极性 DUV LED 的 18.8 mW，N 极性 DUV LED 的壁插效率 (WPE) 在 60 mA 时提高了 104% mA 与 Ga 极性常规 DUV LED 结构相同。此外，还注意到由 p 型夹层和 p-GaN 空穴供应器之间的大能量差异引起的 N 极 DUV LED 的更高工作电压。为了降低 N 极 DUV LED 的工作电压，提出了具有阶梯状 p 型中间层的结构。阶梯状铝成分p型夹层的掺入减轻了空穴注入的大势垒，并且工作电压与Ga-polar DUV LED相当。降低的工作电压进一步提高了 N 极 DUV LED 的 WPE。因此，结合N极DUV LED提升的电子阻挡能力和降低的空穴势垒，大幅增强的WPE在60 mA时高达4.9%，是Ga极DUV LED的2.88倍。