3175 PPI AlGaInP基红光Micro-LED及其CMOS驱动背板的凸点制备与键合  

Fabrication and bonding of bumps on 3175 PPI AIGalnP-based red Micro-LED and its CMOS driver

作　　者：郭成龙 王学燕 周毅坚 朱学奇 鄢支兵 杨天溪 李晋 李洋 孙捷 严群[1] Chenglong Guo;Xueyan Wang;Yijian Zhou;Xueqi Zhu;Zhibing Yan;Tianxi Yang;Jin Li;Yang Li;Jie Sun;Qun Yan(National and Local United Engineering Laboratory of Flat Panel Display Technology,Fuzhou University,and Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China,Fuzhou 350100,China;Quantum Device Physics Laboratory,Chalmers University of Technology,Gothenburg 41296,Sweden)

机构地区：[1]福州大学平板显示技术国家地方联合工程实验室,中国福建光电信息科学与技术创新实验室,福州350100 [2]Quantum Device Physics Laboratory,Chalmers University of Technology,Gothenburg 41296,Sweden

出　　处：《科学通报》2024年第32期4773-4782,共10页Chinese Science Bulletin

基　　金：国家重点研发计划(2023YFB3608703,2023YFB3608700);中国福建光电信息科学与技术创新实验室项目(2021ZZ122,2020ZZ110);福建省科技厅项目(2021HZ0114);国家自然科学基金(12474066)资助。

摘　　要：为了进一步推动微发光二极管(micro light emitting diode, Micro-LED)显示技术的发展进程,本文提出并优化了一种将红光Micro-LED芯片转移至互补金属氧化物(complementary metal oxide semiconductor, CMOS)驱动背板上并与之键合的方案.首先,将制备好阴阳电极的红光Micro-LED芯片由GaAs衬底通过苯并环丁烯(benzocyclobutene, BCB)胶转移至蓝宝石衬底,避免了GaAs衬底对红光的吸收,并提高了衬底的硬度.接着,在转移衬底后的红光Micro-LED芯片上制备铟凸点.在进行CMOS芯片表面绝缘层的刻蚀工艺时,针对不同厚度的绝缘层采用了不同的处理方法.在刻蚀较厚绝缘层时,通过增加额外的电感耦合等离子体(inductively coupled plasma, ICP)刻蚀步骤来替代氧等离子体清洗,解决了光刻存在的残胶问题以及氧等离子体清洗导致的孔径变大问题.最后,我们在0.7英寸(1 in=2.54 cm)的CMOS芯片上制备好2.23μm高的金属凸点并将其与带有铟凸点的红光Micro-LED芯片键合,成功制备了像素周期为8μm、分辨率为1920×1080、像素密度为3175 ppi的Micro-LED显示样机,通过CMOS芯片驱动Micro-LED芯片可显示指定图案.该工作对于高像素密度、高分辨率的CMOS驱动背板凸点制备及键合工艺,以及红光Micro-LED显示器的制备有着重要的参考价值,对推动Micro-LED实用化作出了贡献.In recent years,people have increasingly demanded both the quantity and quality of information conveyed by display technology.Therefore,micro light emitting diode(Micro-LED)display technology is crucial in facilitating immersive interaction between individuals and information,such as in augmented reality(AR)and virtual reality(VR),due to its advantages of high contrast,high brightness,long lifespan,and low power consumption.However,to excel as a widely used display technology,an unavoidable topic is achieving its full-color technology.As a popular research object for red LED luminescent materials,AIGalnP has certain research value in realizing the full-color technology of Micro-LED.Due to its lattice matching with GaAs,it is frequently grown on GaAs substrates.Nevertheless,the GaAs substrate's light absorption for AiGalnP will result in a diminished light extraction efficiency for red light.Hence,it is worthwhile to investigate the resolution to the issue of enhancing the light extraction efficiency of AIGalnP red Micro-LED.Simultaneously,the high-speed response and small size of the complementary metal oxide semiconductor(CMOS)chip enable the Micro-LED driven by it to achieve higher performance and higher pixel density.However,in reports on the production process of high pixel density Micro-LED display screens,the emphasis is typically placed on the production of Micro-LED chips,while the fabrication of bumps and the bonding process on CMOS chips receives less attention.Whether the process on the CMOS chip can be done well is also the key to the industrialization of Micro-LED displays in the future.In order to further promote the development of Micro-LED display technology,this paper proposed and optimized a scheme to transfer the red Micro-LED chip to the CMOS driver and bond with it.Initially,the red Micro-LED chip with equipped cathode and anode electrodes was transferred from the GaAs substrate to the sapphire substrate using benzocyclobutene(BCB)glue,which avoided the absorption of red light by the GaAs sub

关 键 词：微发光二极管 互补金属氧化物 凸点 刻蚀 键合 

分 类 号：TN312.8[电子电信—物理电子学]