摘要
为提高氮化镓(Ga N)基发光二极管(LED)的光提取效率,基于等效介质理论设计了底面100%占空比、半径为320 nm的正方形孔径纳米半球阵列。利用时域有限差分法(FDTD)对正方形孔径纳米半球阵列结构底面占空比、半径对光提取效率的影响进行了仿真计算研究。仿真结果表明:LED p-Ga N表面刻蚀半径为320 nm、底面占空比为100%的正方形孔径纳米半球阵列的光提取效率最优。采用电子束曝光配合热回流技术和ICP刻蚀完成正方形孔径纳米半球阵列的Ga N基LED制作及测试实验。结果表明:在20 m A和150 m A工作电流下,有微纳结构的LED较无微纳结构的参考样品的发光效率分别提高4.67倍和4.59倍,计算结果与实验结果比较一致,说明加入方形孔径纳米半球阵列可以有效提高LED光提取效率。
Based on the equivalent medium theory,an square aperture nano-hemisphere structure with bottom surface fill-factor of 100% and spherical vector height of 320 nm was designed and put into use in the course of experiment as it sought to make Ga N-based LED more efficient. Guided by the finite-difference time-domain method（ FDTD）,a simulation research on how the parameters of structure influenced the light extraction efficiency performance,such as the spherical vector height,the bottom surface fill-factor was schemed to be conducted in the experiment. The study provided the evidence that the optical light extraction efficiency could be achieved on the occasion that the square aperture nano-hemisphere array with a radius of 320 nm and a bottom surface fill-factor 100% pGa N was etched and presented on the surface of LED. Such technologies as electron beam exposure combined with thermal reflow and ICP etching should be applied and come into service for building square aperture nano-hemisphere arrays. In strict accordance with calculation results,under the working current of 20 m A and 150 m A,the luminous efficiency of the LED with the nano structure is4. 67 times and that of the reference sample is less than 4. 59 times,which shows that square aperture nano-hemisphere array promises to help make the light extraction efficiency of LED better,according to the electroluminescence test.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2017年第12期1668-1674,共7页
Chinese Journal of Luminescence
基金
总装预研基金(9140A10011515BQ03135)资助项目~~
关键词
发光二极管
时域有限差分法
纳米半球
光提取效率
电致发光
LED
finite-difference time-domain method
nano-hemisphere
light extraction efficiency
electroluminescence
