激光诱导放电等离子体极紫外辐射的模拟  

Simulation of extreme ultraviolet radiation of laser induced discharge plasma

作　　者：王均武 玄洪文 俞航航 王新兵[2] Vassily S.Zakharov Wang Jun-Wu;Xuan Hong-Wen;Yu Hang-Hang;Wang Xin-Bing;Vassily S.Zakharov(GBA Research Institute of AIRCAS,Guangzhou 510700,China;Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,China;Keldysh Institute of Applied Mathematics,Moscow 125047,Russia;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]广东大湾区空天信息研究院,广州510700 [2]华中科技大学武汉国家光电研究中心,武汉430074 [3]凯尔迪什应用数学研究所,莫斯科125047 [4]中国科学院大学,北京100049

出　　处：《物理学报》2024年第1期258-265,共8页Acta Physica Sinica

基　　金：广州市基础与应用基础研究专题(批准号:2023A04J0024);中国科学院人才引进计划(批准号:E33310030D);中国科学院空天信息创新研究院(批准号:E1Z1D101,E2Z2D101)资助的课题。

摘　　要：极紫外光刻是目前新一代超高集成度半导体芯片制造流程中重要的一环,激光诱导放电等离子体是极紫外光源产生的重要技术手段之一.本文基于全局状态方程、原子结构计算程序、碰撞辐射模型建立了一个辐射磁流体力学模型,对激光诱导放电等离子体的动力学特性及极紫外的辐射特性进行模拟,模拟复现了放电过程中的箍缩现象,得到的极紫外光的转化效率与实验符合.研究发现放电电流的上升速率对极紫外光的产生有极大的影响,该结果对后续极紫外光输出功率、转化效率以及光谱纯度的提升有重要的指导意义.Extreme ultraviolet(EUV)light source is an important part of EUV lithography system in semiconductor manufacturing.The EUV light source requires that the 4p~64d~n-4p~54d~(n+1)+4d~(n–1)4f transitions of Sn~(8+~13+)ions emit thousands of lines which form unresolved transition arrays near 13.5 nm.Laser-induced discharge plasma is one of the important technical means to excite target into an appropriate plasma condition.Laser-induced discharge plasma has a simple structure and a low cost.It also has important applications in mask inspection,microscopic imaging,and spectral metrology.In the design and production process,there are many factors that can influence the conversion efficiency,such as current,electrode shape,and laser power density.The simulation method is a convenient way to provide guidance for optimizing the parameters.In this paper,a completed radiation magneto-hydrodynamic model is used to explore the dynamic characteristics of laserinduced discharge plasma and its EUV radiation characteristics.To improve the accuracy,a more detailed global equation of state model,an atomic structure calculation model including relativistic effect and a collision radiation model are proposed simultaneously.The simulation reconstructs the discharge process effectively,which is divided into five stages in the first half cycle of current,including expansion of laser plasma,column formation of discharge plasma,diffusion of discharge plasma,contraction of discharge plasma,and re-diffusion of discharge plasma.It is revealed that the pinch effect during the current rising time exerts a significant influence on the generation of EUV radiation.The conversion efficiency of EUV radiation is still low under our existing conditions,and hopefully a higher rising rate of current can improve the conversion efficiency in the future work.

关 键 词：辐射磁流体力学 激光诱导放电等离子体 碰撞辐射模型 极紫外光 

分 类 号：O53[理学—等离子体物理] TN405[理学—物理]