侧壁粗化提高GaN基发光二极管出光效率的研究  

Enhanced Light Output Efficiency of GaN-based Light-emitting Diodes by Sidewall Texturing

作　　者：李晓莹[1] 朱丽虹[1] 邓彪 张玲[1] 刘维翠 曾凡明[1] 刘宝林[1] 

机构地区：[1]厦门大学物理与机电工程学院,福建厦门361005 [2]晶能光电有限公司,江西南昌330029

出　　处：《厦门大学学报（自然科学版）》2015年第3期384-389,共6页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(11104230;60276029)

摘　　要：采用工艺成熟且成本低廉的芯片技术实现侧壁粗化以提高GaN基发光二极管(LED)的出光效率是备受关注的研究课题.通过普通光刻技术和感应耦合等离子体(ICP)刻蚀技术在器件内部引入侧壁粗化结构,有效提高了LED芯片的出光效率.由于侧壁几何微元结构的改变,光线到达该界面位置处的全反射作用得到抑制而使芯片的出光总量增加.结果表明,注入电流为350 mA时,具有三角状侧壁粗化结构的LED芯片比传统LED芯片的输出光功率增加20.6%,出光效率提升20.5%,并且侧壁粗化后不会影响LED芯片的电学性能和发光稳定性.光强空间分布特性显示,发光强度的增加主要位于-35°^-20°和+20°^+35°的斜角范围内.Using the mature and low-cost chip technology to achieve textured sidewalls for more efficient GaN-based light-emitting diodes（LED）has become a research focus.In this paper,the conventional lithography and inductively coupled plasma（ICP）etching techniques are adopted to fabricate LED chips with the sidewall-textured structure to enhance the light output efficiency.Due to micro-geometrical changes of sidewalls,the output intensity of the laterally propagated light can be improved by suppressing the total internal reflection at interfaces.The result shows that the light output power of the LED chips with triangle-textured sidewalls is enhanced by 20.6%,which leads to an increase of 20.5%in light output efficiency,as compared to that of conventional LED chips at an injection current of 350 mA.Meanwhile,the electrical performance is not obviously degraded and the electroluminescence is stable after the sidewall texturing.The light emission pattern indicates that the enhancement appears primarily along the oblique directions,within the angle regions of-35°to-20°and ＋20°to＋35°.

关 键 词：GAN 发光二极管 感应耦合等离子体(ICP)刻蚀 侧壁粗化 出光效率 

分 类 号：TN383.1[电子电信—物理电子学]