基于阴影法的脉冲CO<sub>2</sub>激光Sn等离子体羽辉膨胀特性研究

基于阴影法测量了脉冲CO2激光Sn等离子体羽辉在缓冲气体中的膨胀特性，得到了羽辉边界位置及其等离子体碎屑动能随延时的变化规律，并利用修正的阻力扩散模型拟合了实验数据。研究表明，在入射激光脉冲能量为400 mJ，脉冲半峰全宽为75 ns，缓冲空气气压为1000 Pa时，初期(延时小于100 ns)Sn等离子体羽辉边界的膨胀速度可以达到3 cm/μs，随着延时的增加，由于背景气体分子的热碰撞阻力作用，羽辉粒子的速度急剧下降，后期(延时大于800 ns)羽辉碎屑离子膨胀速度降到了0.3 cm/μs。修正的阻力扩散模型拟合的结果表明等离子体羽辉膨胀的极限尺寸xst=15.2 mm，实验测试结果表明，羽辉碎屑粒子运动的极限距离约为16 mm，理论模型与实验结果吻合较好。

Abstract

The characteristics of pulsed CO2 laser produced Sn plasma plume expansion under ambient air pressures are studied by shadowgraph technique. The dependences of Sn plume expansion position and plasma debris energy on delay time are obtained. The modified drag diffusion model is employed to fit the experimental data. Plasmas are generated by irradiating planar Sn targets using 400 mJ, 75 ns pulses from a CO2 laser. Our results show that the estimated expansion velocity of the plasma in the early stage (delay time is less than 100 ns) is almost 3 cm/μs, and decreases rapidly with delay time to about 0.3 cm/μs at later stage (delay time is larger than 800 ns) because of the thermalization collisions with buffer gas pressure of 1000 Pa. Fitting results of modified drag diffusion model indicate that the plasma plume maximum size is xst=15.2 mm, which is found to agree fairly well with the measured data of 16 mm.

参考文献

[1] J. Finders, M. Dusa, P. Nikolsky et al.. Litho and patterning challenges for memory and logic applications at the 22 nm node［C］. SPIE, 2010, 7640: 76400C

[2] V. Banine, R. Moors. Plasma source or EUV lithography exposure tools［J］. J. Phys. D: Appl. Phys., 2004, 37(23): 3207～3210

[3] 吴涛, 王新兵, 唐建等. CO2激光锡等离子体极端紫外及可见光光谱［J］. 光学学报, 2012, 32(4): 0430002

Wu Tao, Wang Xinbing, Tang Jian et al.. Extreme ultraviolet and visible emission spectroscopic characterization of CO2 laser produced tin plasma for lithography［J］. Acta Optica Sinica, 2012, 32(4): 0430002

[4] V. Bakshi. EUV Sources for Lithography［M］. Washington: SPIE Press, 2006. 3～41

[5] Y. Tao, M. S. Tillack, S. Yuspeh et al.. Interaction of a CO2 laser pulse with tin-based plasma for an extreme ultraviolet lithography source［J］. IEEE Trans. Plasma Sci., 2010, 38(4): 714～718

[6] S. S. Harilal, T. Sizyuk, A. Hassanein et al.. The effect of excitation wavelength on dynamics of laser-produced tin plasma［J］. J. Appl. Phys., 2011, 109(6): 063306

[7] S. Yuspeh, Y. Tao, R. A. Burdt et al.. Dynamics of laser-produced Sn microplasma for a high-brightness extreme ultraviolet light source［J］. Appl. Phys. Lett., 2011, 98(20): 201501

[8] J. R. Freeman, S. S. Harilal, A. Hassanein. Enhancements of extreme ultraviolet emission using prepulsed Sn laser-produced plasmas for advanced lithography applications［J］. J. Appl. Phys., 2011, 110(8): 083303

[9] Wu Tao, Wang Xinbing, Wang Shaoyi et al.. Time and space resolved visible spectroscopic imaging CO2 laser produced extreme ultraviolet emitting tin plasmas［J］. J. Appl. Phys., 2012, 111(6): 063304

[10] 吴涛, 王新兵, 王少义等. 基于脉冲CO2激光锡等离子体光刻光源的极紫外辐射光谱特性研究［J］. 光谱学与光谱分析, 2012, 32(7): 1729～1733

Wu Tao, Wang Xinbing, Wang Shaoyi et al.. Characteristics of extreme ultraviolet emission from tin plasma using CO2 laser for lithography［J］. Spectroscopy and Spectral Analysis, 2012, 32(7): 1729～1733

[11] Y. Ueno, G. Soumagne, A. Sumitani et al.. Reduction of debris of a CO2 laser-produced Sn plasma extreme ultraviolet source using a magnetic field［J］. Appl. Phys. Lett., 2008, 92(21): 211503

[12] D. Bleiner, T. Lippert. Stopping power of a buffer gas for laser plasma debris mitigation［J］. J. Appl. Phys., 2009, 106(12): 123301

[13] S. S. Harilal, C. V. Bindhu, M. S. Tillack et al.. Internal structure and expansion dynamics of laser ablation plumes into ambient gases［J］. J. Appl. Phys., 2003, 93(5): 2380～2388

[14] D. B. Geohegan. Physics and diagnostics of laser ablation plume propagation for high-Tc superconductor film growth［J］. Thin Solid Films, 1992, 220(1-2): 138～145

[15] A. V. Rode, E. G. Gamaly, B. Luther-Davies. Formation of cluster-assembled carbon nano-foam by high repetition-rate laser ablation［J］. Appl. Phys. A, 2000, 70(2): 135～144

[16] A. Bailini, P. M. Ossi. Modelling the propagation of an ablation plume in a gas［J］. Radiation Effects & Defects in Solids, 2008, 163(4-6): 497～503

吴涛, 王新兵, 王世芳, 谭荣. 基于阴影法的脉冲CO₂激光Sn等离子体羽辉膨胀特性研究[J]. 中国激光, 2013, 40(1): 0102003. Wu Tao, Wang Xinbing, Wang Shifang, Tan Rong. Research on Pulsed CO2 Laser Produced Sn Plasma Plume Expansion Properties by Shadowgraph Technique[J]. Chinese Journal of Lasers, 2013, 40(1): 0102003.

基于阴影法的脉冲CO₂激光Sn等离子体羽辉膨胀特性研究

关于本站 Cookie 的使用提示

全站搜索

基于阴影法的脉冲CO2激光Sn等离子体羽辉膨胀特性研究

相关论文

相关资讯

关于本站 Cookie 的使用提示

全站搜索

基于阴影法的脉冲CO₂激光Sn等离子体羽辉膨胀特性研究