Radiative and Auger Recombination Constants and Internal Quantum Efficiency of (0001) AlGaN Deep‐UV Light‐Emitting Diode Structures
Radiative and Auger Recombination Constants and Internal Quantum Efficiency of (0001) AlGaN Deep‐UV Light‐Emitting Diode Structures
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(0001) AlGaN 深紫外发光二极管结构的辐射和俄歇复合常数以及内量子效率
DOI：
10.1002/pssa.201900878
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
S. Karpov
中科院分区：
文献类型：
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作者：
M. Rudinsky;S. Karpov
采用通过成分波动解释空穴定位的半经验模型来估计 (0001) AlGaN 量子阱中的辐射和俄歇复合常数，该量子阱用作深紫外 (UV) 发光二极管 (LED) 的有源区域。利用直接测量的 Al0.25Ga0.75N 合金和量子阱中的空穴局域化长度对该模型进行了初步校准。发现复合常数随合金成分/发射波长非单调变化。器件模拟与估计的复合常数相结合，可以识别限制 LED 结构内部量子效率的主要因素：各种复合通道的竞争以及分别在长于和短于 240 nm 的波长下通过电子阻挡层的电子泄漏。将预测的复合常数与块状 AlGaN 合金和 Al0.45Ga0.55N/AlN 量子阱的可用数据进行了比较。
A semiempirical model accounting for hole localization by composition fluctuations is applied to estimate the radiative and Auger recombination constants in (0001) AlGaN quantum wells serving as active regions of deep‐ultraviolet (UV) light‐emitting diodes (LEDs). The model is preliminarily calibrated using the directly measured hole localization lengths in Al0.25Ga0.75N alloys and quantum wells. The recombination constants are found to vary nonmonotonously with the alloy composition/emission wavelength. Device simulations combined with the estimated recombination constants enable identification of major factors limiting the internal quantum efficiency of the LED structures: competition of various recombination channels and electron leakage through the electron‐blocking layer at wavelengths longer and shorter than ≈240 nm, respectively. Comparison of the predicted recombination constants with the data available for bulk AlGaN alloys and Al0.45Ga0.55N/AlN quantum wells is done.