大功率射频板条CO_(2)激光器  

High-Power Radio-Frequency Slab CO_(2) Laser

作　　者：唐霞辉[1] 秦应雄[1] 彭浩[1] 李玉洁 吴洋 肖龙胜 肖瑜[1] 柳娟 Tang Xiahui;Qin Yingxiong;Peng Hao;Li Yujie;Wu Yang;Xiao Longsheng;Xiao Yu;Liu Juan(School of Optics and Electronic Information,Huazhong Unicersity of Science and Techuology,Wuhan 430074,Hubei,China;College of Physics and Electromechanical Engineering,Hubei Unicersity of Education,Wuhan 430205,Hubei,China;College of Aeronautics and Astronautics,Xiamen University,Xiamen 361005,Fujian,China)

机构地区：[1]华中科技大学光学与电子信息学院,湖北武汉430074 [2]湖北第二师范学院物理与机电工程学院,湖北武汉430205 [3]厦门大学航空航天学院,福建厦门361005

出　　处：《中国激光》2022年第12期79-92,共14页Chinese Journal of Lasers

摘　　要：大功率射频板条CO_(2)激光器曾经是深熔焊接、切割的主力光源,目前主要用于超大规模集成电路晶圆退火。华中科技大学于2007年就开始了大功率射频板条CO_(2)激光器的研发,并进行大量的理论研究和产业化工作。本文介绍了射频板条CO_(2)激光器的国内外发展动态;重点分析了激光器的结构设计、(板条)面积放大、扩散冷却、激励电源、射频传输、阻抗匹配、射频气体放电等离子体、放电均匀性、电极热效应、非稳-波导混合腔、激光功率提取、输出光束特性、光束整形等核心技术;展望了射频板条CO_(2)激光器在超大规模集成电路晶圆激光退火中的重要创新应用。Significance Around the world,high-power CO_(2) laser has been the main light source for laser cutting,welding,and surface treatment,including cross-flow CO_(2) laser,axial fast-flow CO_(2) laser,and radio-frequency(RF)slab CO_(2) laser.RF-excited diffusion-cooled slab CO_(2) laser has compact structure and high beam quality,which once could not be achieved by all gas lasers above kilowatt level.It has an important application in the field of plate cutting and welding and represents the development direction of CO_(2) gas laser.However,with the rapid development of fiber laser,the CO_(2) laser metal processing market has almost been replaced by fiber laser.Yet,in recent years,RF slab CO_(2) laser has been the only one used for laser annealing of VLSI wafers,with no other laser to replace it.Today,two types of annealing equipment are mainly used in the annealing of integrated circuit wafers.One is the traditional rapid thermal processing(RTP)equipment.The RTP equipment uses halogen tungsten lamps to heat a single wafer to 300℃--1050℃within 1--30s.In addition,it has been adopted by semiconductor manufacturing industry for more than 20 years.Another novel heat treatment method is millisecond annealing(MSA),which can heat the wafer to 1100℃--1350℃(just below the melting point of silicon)in a few hundred microseconds to a few milliseconds.MSA can be realized using two different methods:laser spike annealing(LSA)or flash laser annealing.LSA uses long-wavelength CO_(2) laser beam to irradiate the semiconductor wafer at grazing angle to form a “line beam” on the wafer surface to scan the wafer back and forth.For the formation of USJ(ultra shallow junction)and nickel silicide,each method has its own challenges.With the reduction of device size,the formation of nickel silicide is a new challenge in wafer manufacturing.Conventional formation of nickel silicide includes two low-temperature RTP steps and an optional etching step between the two steps.When the device size is reduced to 28nm or even smaller,the nick

关 键 词：激光器 大功率射频板条CO_(2)激光器 扩散冷却 非稳-波导混合腔 光束整形 射频激励 气体放电 

分 类 号：TN248.2[电子电信—物理电子学]