蓝宝石衬底上的半极性面GaN基LED超快激光剥离  

Ultrafast Laser Lift-off of Semipolar GaN-based LEDs on Sapphire Substrates

作　　者：项文辞 孙浩 王思博 周慧莲 帅凌霄 叶云霞 张韵 XIANG Wenci;SUN Hao;WANG Sibo;ZHOU Huilian;SHUAI Lingxiao;YE Yunxia;ZHANG Yun(Department of Optoelectronic Information Science and Engineering,School of Mechanical Engineering,Jiangsu University,Zhengjiang 212013,China)

机构地区：[1]江苏大学机械工程学院光电信息科学与工程系,江苏镇江212013

出　　处：《发光学报》2024年第4期681-687,共7页Chinese Journal of Luminescence

基　　金：国家自然科学基金(61904068);中国博士后科学基金(2021T140304);江苏大学科研基金(19JDG020)。

摘　　要：衬底导电性和导热性差一直是困扰生长于蓝宝石衬底上的GaN基LED的难题,利用激光剥离技术将蓝宝石衬底上的GaN基LED转移至其他衬底是解决该问题的有效方法之一。本文使用超快皮秒激光将生长于图案化蓝宝石衬底上的半极性面GaN基LED进行衬底剥离,并成功转移至Si衬底,形成垂直结构的LED器件。利用SEM测试发现,当超快激光能量密度在1.3 J/cm^(2)附近可以有效分解蓝宝石和GaN交界层,且对器件产生最小负面损伤。拉曼光谱测试结果表明,剥离后的LED中GaN层的残余应力得到有效释放,从1.42 GPa降低为0.29 GPa。对制备的垂直结构LED进行I-V性能测试,5 V电压下正向电流由0.164 mA增大至0.759 mA,光致发光和电致发光性能均有增强。本文完成了蓝宝石衬底上的半极性面GaN基LED超快激光剥离的实验研究,为实现低损伤、高效率的转移技术的开发提供理论支撑,有望加速半极性面GaN基LED的发展与应用。The poor substrate conductivity and thermal properties have been a big challenge for GaN-based LEDs grown on sapphire substrates.Utilizing laser lift-off technology to transfer GaN-based LEDs from sapphire substrates to alternative substrates has emerged as an effective solution.This paper employed ultrafast picosecond laser to detach semi-polar GaN-based LEDs overgrown on patterned sapphire substrates and successfully transfered them to Si substrates,forming vertical structure LED devices.SEM measurements revealed that at a laser energy density of 1.3 J/cm²,efficient decomposition of the sapphire and GaN interface occurred,minimizing adverse effects on the devices.Raman spectroscopy results demonstrated effective stress release in the GaN layer,in which the residual stress decreases from 1.42 GPa to 0.29 GPa.I-V measurements of the fabricated vertical structure LEDs showed an increase in forward current from 0.164 mA to 0.759 mA at 5 V voltage,along with an enhancement in photoluminescence and electroluminescence performances.This study presents experimental research on ultrafast laser lift-off of semi-polar GaN-based LEDs on sapphire substrates,providing support for the development of low-damage,high-efficiency transfer technologies.It holds promise in accelerating the advancement and application of semi-polar GaNbased LEDs.

关 键 词：LED 超快激光 图案化蓝宝石 半极性面 氮化镓 

分 类 号：TN364.2[电子电信—物理电子学] TN312.8