为了提高GaN基LED的发光效率, 设计了一种新型LED模型, 该模型主要包括Ag光栅, 氧化铟锡过渡层和P-GaN光栅。首先阐述了利用该结构激发表面等离子体从而改善LED发光特性的原理, 讨论了该模型的加工工艺与制作过程。基于COMSOL软件, 利用有限元法对本文提出的LED模型进行了仿真分析, 得出该模型在不同结构参数下, 归一化辐射功率与归一化损耗功率随波长的变化规律以及电场分布情况。仿真结果表明, 在ITO过渡层厚度为55 nm, 周期为270 nm, 占空比为0.5时, 所设计的GaN基LED模型的发光强度较普通LED提高近30倍, 这一结果为研制高性能GaN基LED提供了可靠基础。

In order to improve the luminous efficiency of GaN based LED, a novel type LED model which mainly includes Ag grating, transition layer of indium tin oxide and P-GaN grating was designed. The method that using the structure to stimulate surface plasma for improving luminous characteristics of LED was explored, and the processing technology and manufacturing process of the model was discussed. Based on COMSOL software, the LED model was simulated by finite element method, revealing the principle for the variation of normalized radiant power and normalized loss power with wavelength and electric field distribution under different structure parameters. The simulation result shows that when the thickness of the transition layer is 55 nm, period is 270 nm and duty circle is 0.5, the luminous intensity of the GaN based LED is increased nearly 30 times of the normal LED, which lays a reliable foundation for the research of GaN based LED with high performance.