Investigating the Recombination Mechanism of V-Pits in InGaN/GaN Multiple Quantum Wells LEDs Combining Hyperspectral Electroluminescence and Cathodoluminescence

作者：Yaqi Cai, Honglin Gong, Weijie Guo, Huanting Chen, Zhong Chen, Yijun Lü, Lihong Zhu · 发表于：ACS Photonics · 年份：2025 · DOI：10.1021/acsphotonics.5c00426 · 被引用次数：4 · 研究领域：GaN-based semiconductor devices and materials、ZnO doping and properties、Semiconductor Quantum Structures and Devices

V-shaped pits (V-pits) significantly affect the performance of InGaN/GaN multiple quantum wells (MQWs) and light-emitting diodes (LEDs), yet their recombination mechanism remains controversial. A deeper understanding of carrier transport and recombination in V-pits is essential. In this study, we proposed a new approach that integrates microhyperspectral electroluminescence (EL), photoluminescence (PL), and cathodoluminescence (CL) into the investigation of the optical and transport properties of V-pits from microscale to nanoscale in green mini-LEDs. Based on analysis of the full-structure device, this approach avoids variations from separately prepared samples. Dual-perspective CL measurements, including top-view and cross-sectional electron-beam injections, reveal three distinct recombination mechanisms in association with V-pit center, V-pit sidewall, and flat MQWs. Additionally, analysis of the peak intensity ratio provides direct evidence of lateral carrier transport from V-pits to surrounding MQWs, uncovering the role of V-pits in modulating recombination dynamics within the quantum wells. PL imaging based on an acousto-optic tunable filter (AOTF) reveals significant spatial separation in luminescence between the V-pit-dominant and the MQWs-dominant area, which validates carrier transport behavior. These findings deepen the understanding toward V-pit-induced recombination mechanisms and offer a framework for improving LED material design, fabrication processes, and dev...