GaN基薄膜LED倒装芯片表面结构设计及光萃取效率研究  

Design of Surface Textures for High Light Extraction Efficiency GaN-based Flip-chip TFLEDs

作　　者：齐赵毅[1,2] 胡晓龙[1] 王洪[1,2] QI Zhao-yi HU Xiao-long WANG Hong(Engineering Research Center for Optoelectronics of Guangdong Province, School of Electronic and Information Engineering, South China University of Technology, Guangzhou 510640, China Academy of Electronics and Information, South China University of Technology, Guangzhou 510640, China)

机构地区：[1]华南理工大学广东省光电工程技术研究开发中心,广东广州510640 [2]华南理工大学电子与信息学院,广东广州510640

出　　处：《发光学报》2017年第3期338-346,共9页Chinese Journal of Luminescence

基　　金：国家高技术研究发展计划(863)(2014AA032609);国家自然科学基金(61404050);广东省重大科技专项(2014B010119002);广东省应用型科技专项资金重大项目(2015B010127013);广州市产学研协同创新重大专项项目(201504291502518)资助~~

摘　　要：利用FDTD方法研究具有表面微纳结构氮化镓基倒装薄膜LED芯片的光萃取效率。通过优化表面结构并研究了器件的光萃取效率随p-Ga N层厚的变化。研究发现,具有表面光子晶体和六棱锥结构的器件的光萃取效率最大值比无表面微结构器件分别提高了56%和97%。尽管两种表面结构都能有效提高器件的光萃取效率,然而采用光子晶体的方案对p-Ga N厚度和腔长要求极为苛刻。采用六棱锥结构则不仅可以获得更高的光萃取效率,并且还将大大降低实验上材料外延生长及器件制备的难度。Light extraction efficiency （LEE） of flip-chip thin-film LEDs （FC-TFLEDs） with differ- ent surface textures were performed by using finite difference time domain method. The surface tex- tures and different thicknesses of p-GaN layer were optimized for high LEE FC-TFLEDs. It is found that the maximum LEE of FC-TFLEDs with photonic crystals and hexagonal cones is 1.56 and 1.97 times to that of FC-TFLEDs with flat surface, respectively. Both types of the surface textures can im- prove the LEE of FC-TFLEDs, however, it is much difficult to obtain high LEE FC-TFLEDs by em- ploying photonic crystals. The simulated results show that the LEE of FC-TFLEDs is effectively im- proved by the use of the hexagonal cones, in addition, it can greatly reduce the difficulty in LED material growth and device fabrication.

关 键 词：倒装薄膜LED FDTD 光萃取效率 光子晶体 六棱锥 

分 类 号：TN383.1[电子电信—物理电子学]