高反射率电极及n-GaN表面粗化的InGaN/GaN多量子阱LED的研制

• 作 者: 林秀其 柳铭岗 杨亿斌 任远 陈扬翔 向鹏 陈伟杰 韩小标 藏文杰 林佳利 罗慧 廖强 张佰君
• 机 构: 中山大学物理科学与工程技术学院光电材料与技术国家重点实验室,
• 出 处: 半导体光电
• 发表日期: 2015年03期
• 关键词: InGaN/GaN LED n-GaN 高反射率 粗化 高反射率电极 表面粗化 光萃取效率 电极 萃取效率

采用高反射率的Cr/Al/Pd/Au作为LED的p-GaN和n-GaN金属电极,替代低反射率的Cr/Pd/Au电极,减小了金属电极对光的吸收,使入射到高反射率金属电极的光经过反射后增加了出射概率,提高了光萃取效率。通过进一步粗化n-GaN表面,抑制了n-GaN/空气界面的光全反射,提高了光萃取效率。实验结果表明,在350mA电流下,采用高反射率的Cr/Al/Pd/Au电极的LED相比传统电极LED光输出增加了14.3%;结合n-GaN表面粗化,LED的光输出则增加了35.3%。

Substituting Cr / Al / Pd / Au with high reflectance for the p-GaN and n-GaN metal electrodes of LEDs, the absorption of light by the metal electrodes is reduced by the substitution of low reflectivity Cr / Pd / Au electrodes, After the reflection of the light of the high-reflectivity metal electrode, the probability of exiting is increased, and the light extraction efficiency is improved. By further roughening the n-GaN surface, the total light reflection at the n-GaN / air interface is suppressed and the light extraction efficiency is improved. The experimental results show that the LED output of Cr / Al / Pd / Au electrode with high reflectivity is increased by 14.3% compared with that of the conventional electrode under the current of 350mA. Combined with the n-GaN surface roughening, the LED light output increases 35.3%.