采用实验与理论模拟相结合的方法, 研究了氮化镓基绿光发光二极管(LED)中V坑对空穴电流分布的影响。首先, 实验获得了V坑面积占比不同的3种样品; 然后, 建立数值模型, 使得理论计算的外量子效率(EQE)及电压与实验测试的变化趋势相匹配, 从而确立了所用数值模型的可信性。计算结果显示: V坑改变了空穴电流的分布, 空穴电流密度在V坑处显著增加, 在平台处明显减小。进一步的分析表明: V坑面积占比在0~10%范围内, V坑空穴电流占比与V坑面积占比之间呈近线性增长(斜率为2.06), 但V坑空穴注入在整个空穴注入的过程中仍未占主导。

The effect of V-shaped pit hole current distributionin GaN based green LED was experimentally and theoretically investigated. First, three LED samples were prepared by experiment, which V-shaped pit area ratio was different. Then, a numerical model was established to match the external quantum efficiency(EQE) and the voltage of the theoretical calculation with the trend of the experimental test, thus the credibility of the numerical model was established. Calculation results show that the V-shaped pit changes the distribution of hole current, the hole current density increases significantly in the V-shaped pit, and reduces significantly at the platform. Further, the analysis shows that the hole current ratio in the V-shaped pit shows a near linear increase with the V-shaped pit area ratio(slope is 2.06) when the V-shaped pit area ratio is in the range of 0-10%, while the V-shaped pit hole injection has not yet dominated the whole hole injection process.