光学学报, 2018, 38 (1): 0122001, 网络出版: 2018-08-31
利用截头圆锥形仿生蛾眼结构提高LED光提取效率 下载: 1177次
Enhancement of Light Extraction Efficiency of LED by Bionic Moth-Eye Structure with Frustum of a Cone
光学设计 发光二极管 亚波长微结构 纳米球 光提取效率 电致发光 optical design light-emitting diode sub-wavelength microstructure nanosphere light extraction efficiency electroluminescence
摘要
为提高发光二极管(LED)光提取效率,根据等效介质理论在LED钝化层(SiNx )表面设计并制作了一种截头圆锥形微结构阵列。通过模拟重点分析了微结构的底面占空比、底面直径、高度和倾角对提高LED光提取效率的影响,得出微结构的底面占空比为0.55、底面半径为220 nm、高度为245 nm、侧面倾角为70°时器件的光提取效率最优,是无表面微结构器件的4.85倍。采用纳米球刻蚀技术在LED钝化层表面制备该亚波长纳米结构,并与无表面微结构的LED芯片进行电致发光对比测试。结果表明,制作有微结构的样品在20 mA和150 mA工作电流下的发光效率是无微结构参考样品的4.41倍和4.36倍,计算结果与实验结果比较一致,说明在LED钝化层制作该结构可有效提高光提取效率。
Abstract
In order to improve the light extraction efficiency of light-emitting diode (LED), according to the equivalent medium theory, microstructure array with frustum of a cone is designed and fabricated in the LED passivation layer (SiNx) surface. The influence of the fill factor of the bottom surface, bottom diameter, height and angle of the micro structure on the light extraction efficiency of LED is emphatically analyzed through simulation.to improve light extraction efficiency of LED. The results show that when the micro structure of the fill factor of the bottom surface is 0.55, the radius of bottom surface is 220 nm, the height is 245 nm, and the side slope angle is 70°, the light extraction efficiency of the device is optimized. Which is 4.85 times as much as the device without surface micro structure. The sub-wavelength nanostructure is prepared on the surface of LED passivation layer by nanosphere lithography technology, and the comparison test of electroluminescent between the proposed structure and LED chip without surface micro structure is carried out. The results show that the luminous efficiency of the samples with micro structure at 20 mA and 150 mA working current are 4.41 times and 4.36 times of the reference samples without micro structure. The calculated results and the experimental results are consistent, which means that the structure produced by the LED passivation layer can effectively improve the light extraction efficiency.
刘顺瑞, 王丽, 孙艳军, 王君, 王越, 吴天祺, 冷雁冰, 董连和. 利用截头圆锥形仿生蛾眼结构提高LED光提取效率[J]. 光学学报, 2018, 38(1): 0122001. Shunrui Liu, Li Wang, Yanjun Sun, Jun Wang, Yue Wang, Tianqi Wu, Yanbing Leng, Lianhe Dong. Enhancement of Light Extraction Efficiency of LED by Bionic Moth-Eye Structure with Frustum of a Cone[J]. Acta Optica Sinica, 2018, 38(1): 0122001.