为了提高倒装发光二极管(LED)光提取效率的同时实现单偏振光输出, 建立了正装、倒装和集成金属亚波长光栅倒装LED 3种模型, 采用RSOFT软件进行仿真对比及器件优化,并进行了理论分析和模拟验证。结果表明, 倒装LED虽然可以提高光提取效率但对P-GaN层厚非常敏感, 无法单偏振光输出; 集成了金属亚波长光栅的倒装LED可以不受P-GaN层厚影响, 实现单偏振光输出, 但要输出稳定偏振光, 受光栅参量和介质过渡层厚度影响非常显著;优化后的结构可以实现57.63%的光提取效率, 偏振消光比达到25.8dB。该研究对制造高性能蓝光LED具有一定的指导作用。

In order to improve light extraction efficiency of a flip-chip light-emitting diode (LED) and realize single polarization light output, three models of normal, flip-chip and integrated metal sub-wavelength grating flip-chip LED were established. RSOFT software was used to simulate and optimize the device, and theoretical analysis and simulation verification were carried out. The results show that, flip-chip LED can improve the light extraction efficiency, but it is very sensitive to the thickness of P-GaN layer and can not output single polarized light. Flip-chip LED integrated with metal sub-wavelength grating can achieve single polarized light output without the influence of P-GaN layer thickness; this kind of LED can output stable polarized light, but it is heavily affected by grating parameters and thickness of transition layer. The thickness of transition layer and parameters are very significant. By optimizing the structure, the extraction efficiency can reach 57.63% and the polarization extinction ratio can reach 25.8dB. The research has some guidance for manufacturing blue ray LED with high performance.