等离子体密度对放电等离子体极紫外光源影响研究  

Effect of Plasma Density on Discharge Produced Plasma Extreme Ultraviolet Source

作　　者：徐强[1] 赵永蓬[2] 王骐[2] 杨永涛[1] 

机构地区：[1]东北林业大学理学院,黑龙江哈尔滨150040 [2]哈尔滨工业大学可调谐激光技术国家级重点实验室,黑龙江哈尔滨150001

出　　处：《光谱学与光谱分析》2017年第8期2560-2563,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(61505025);国家科技重大专项(2008ZX02501-001);中央高校基本科研业务费专项(2572015BX09)资助

摘　　要：等离子体状态是决定极紫外光源功率和转换效率的最重要因素之一,理论和实验研究上Xe气流量对放电等离子体极紫外光源辐射谱和等离子体状态的影响,对于优化光源工作条件具有重要的意义。理论上,采用碰撞-辐射模型,模拟了非局部热力学平衡条件下,不同电离度的离子丰度分布随电子温度和离子密度的变化。推导了Xe8+~Xe11+离子4d-5p跃迁谱线强度随电子温度的变化趋势。实验上,采用毛细管放电机制,利用罗兰圆谱仪测量和分析了不同等离子体密度条件下,放电等离子体极紫外光谱的变化,分析了Xe气流量对等离子体状态的影响。理论和实验结果表明:相同的电流条件下,等离子体箍缩时的平均电子温度随着Xe气流量的增加而降低。对于4d-5p跃迁,低电离度离子与高电离度离子谱线强度的比值随着温度的增加而减少。电流28kA、Xe气流量0.4sccm(cm3·min-1)时,等离子体Z箍缩平均电子温度位于29eV附近。Xe气流量增加时,受离子密度和最佳电子温度的影响,实现Xe10+离子4d-5p跃迁13.5nm(2%带宽)辐射谱线强度最优化的Xe气流量位于0.3~0.4sccm之间。Condition of the plasma is one of the key factors affecting the power and the conversion efficiency of the expreme ultraviolet（EUV）source.The effects of the Xe flow rate on spectra and plasma for discharge produced plasma extreme ultraviolet source were investigated theoretically and experimentally,which was important to optimize the running condition of the EUV source.Moreover,the relationship between the distributions of abundances of ions and electron temperature as well as the density under non-local thermodynamic equilibrium were simulated with the Collisional-Radiation model.The variation tendency of the intensity for Xe8＋～Xe11＋ 4d-5p transitions on electron temperature was derived.The spectra detected by the rowland spectrometer was detected and analyzed under different density of the plasma with the capillary discharge produced plasma technology.Meanwhile,the effect of Xe gas flow rate on the condition of the plasma was studied as well.The experiments and theory showed that,during the Z-pinch process,the temperature decreased when the flow rate of Xe was increasing.And the average electron temperature was approximated to 29 eV when the current was 28 kA and the flow rate of Xe was 0.4 sccm.Meanwhile,the optimal flow rate for 13.5 nm（2%bandwidth）emission,mainly due to 4d-5p transition of Xe10＋ ions,was among 0.3～0.4 sccm.

关 键 词：放电等离子体 极紫外辐射 毛细管放电 极紫外光源 

分 类 号：TN23[电子电信—物理电子学]