GaN基垂直结构LED的n型电极结构设计及芯片制备  

n-type Electrode Patterns Design and Device Fabrication of GaN-based Vertical Structure LEDs

作　　者：刘丽[1] 胡晓龙[1] 王洪[1] 

机构地区：[1]华南理工大学广东省光电工程技术研究中心,物理与光电学院,广东广州510640

出　　处：《发光学报》2016年第3期338-345,共8页Chinese Journal of Luminescence

基　　金：国家高技术研究发展计划(863计划)(2014AA032609);国家自然科学基金(61404050);广东省战略性新兴产业专项资金(2012A080302003);中央高校基本科研业务费(2014ZM0036)资助项目

摘　　要：首先利用电流路径模型分析n型电极尺寸及间距等对垂直结构发光二极管(VS-LEDs)电流分布均匀性的影响,依此设计出一种螺旋状环形结构电极。其次,通过建立有限元分析软件Comsol仿真模型模拟VSLEDs有源层的电流密度分布,发现螺旋状环形结构电极的环间距越小,电流密度分布越均匀。最后,利用VS-LEDs芯片制备技术实现具有螺旋状环形电极的垂直结构LED芯片。实验结果显示,在350 m A电流驱动下,电极环间距为146.25μm的芯片具有最大的功能转换效率,达到26.8%。The influences of size and spacing of n-type electrode on the current distribution of verti- cal-structure light-emitting diodes （VS-LEDs） were firstly analyzed by two-dimension circuit model- ing, and annulospiral n-type electrodes were proposed for the fabrication of VS-LEDs. Then, finite element analysis model in Comsol Multiphysics was built to study the current density distribution in the active layer of VS-LEDs with the annulospiral electrodes. It is found that the current density distribution became more uniform when the electrode spacing reduced. Finally, VS-LEDs with various annulospiral electrodes were fabricated using high-reflectivity p-type Ohmic electrode, copper substrate electroplating and laser lift-off techniques. The wall plug efficiency of VS-LEDs with the elec- trode spacing of 146.25 Ixm is 26.8% at 350 mA, which is higher than that of VS-LEDs with other electrode spacings.

关 键 词：氮化镓 垂直结构发光二极管 电流分布 螺旋状环形结构电极 

分 类 号：TN383.1[电子电信—物理电子学]