合束方式提高准分子激光输出脉冲能量稳定性  

Improvement of the stability of excimer laser output pulse energy by beam combination

作　　者：刘墨林 刘嘉仪 王怡哲 喻学昊 方晓东 游利兵 Liu Molin;Liu Jiayi;Wang Yizhe;Yu Xuehao;Fang Xiaodong;You Libing(College of New Materials and New Energies,Shenzhen Technology University,Shenzhen 518118,China;Shenzhen Shengfang Technology Co.,Ltd.,Shenzhen 518173,China)

机构地区：[1]深圳技术大学新材料与新能源学院,广东深圳518118 [2]深圳盛方科技有限公司,广东深圳518173

出　　处：《红外与激光工程》2024年第1期127-135,共9页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(62175167);广东省科技计划项目(2021QN02Z552);广东省重点建设学科科研能力提升项目(2021ZDJS112);深圳市科技计划项目(JCYJ20210324120207021,JSGG20220831094202005,KQTD20170331115422184)。

摘　　要：为了获得稳定性更好、能量更大的准分子激光输出脉冲,对合束方式提高输出脉冲能量稳定性的可行性进行了理论推导、模拟实验以及合束实验研究。从理论推导得知,当激光输出脉冲能量符合正态分布时,多台激光器合束可以降低输出能量相对标准差。对三台输出脉冲能量分布特性符合正态分布的准分子激光器进行合束模拟实验研究,每台输出脉冲能量平均值约为153 mJ,脉冲能量相对标准差约为1%。两台准分子激光器合束时得到输出脉冲能量平均值为305 mJ、能量相对标准差为0.7%的准分子激光脉冲。三台准分子激光器合束时可以得到输出能量平均值为458 mJ、能量相对标准差为0.6%的准分子激光脉冲。使用两台准分子激光器进行三次实际合束实验,其中两台准分子激光器三次合束分别输出能量平均值约为355、350、330 mJ,相对标准差为1.3%、1.2%、1.4%的激光脉冲;三次合束后分别得到能量平均值为687、694、646 mJ,相对标准差为0.86%、0.79%、0.83%的激光脉冲。模拟实验以及合束实验都表明,合束后的能量相对标准差均小于单台能量相对标准差,即合束提高准分子输出脉冲的稳定性。因此,当单台准分子激光输出脉冲能量符合正态分布且平均能量相当时,多台合束可以有效提高激光输出脉冲的能量稳定性。Objective UV excimer lasers have the characteristics of short wavelength,high power and narrow linewidth,and are widely used in semiconductor lithography,new display manufacturing,corneal refractive correction,etc.Whether in the fields of medical treatment,industry,flat panel processing,or scientific research,the pulse energy stability of excimer lasers is a very important parameter,which directly determines the accuracy of surgery,the critical dimensions of processing,and the uniformity of material processing.Limited by the composition and proportion of working gas,gas circulation system,stability of excitation source,laser resonance amplification mechanism,etc.,the energy stability of excimer laser pulses output by current excimer lasers generally fluctuates around 1%-2%,and it is difficult to further improve.However,the pulse energy stability directly affects the development of industrial production,medical treatment,and scientific research.For example,in the field of integrated circuit manufacturing,the lithography process determines the key dimensions of the device,while the exposure light source directly affects the quality of lithography.The instability of the laser light source may cause pattern deformation and poor registration effect.Therefore,it is of great significance to further improve the output energy stability of excimer lasers based on the existing technology.In practical use,it has been found that when two excimer lasers are used in beam combination,the pulse energy stability is also improved to some extent while the output power is increased.Methods In order to obtain more stable and powerful excimer laser output pulses,theoretical derivation,simulation experiments,and beam combination experiments were conducted to investigate the feasibility of improving the stability of output pulse energy through beam combination.Theoretical derivation showed that when the laser output pulse energy follows a normal distribution,beam combination of multiple lasers with similar parameters can reduce the relat

关 键 词：准分子激光 脉冲能量 稳定性 相对标准差 

分 类 号：TN23[电子电信—物理电子学]