中文摘要：

极紫外光源功率是影响光源使用的关键参数，研究放电等离子体EUV光源等离子体时间特性，优化放电结构和光源功率具有重要意义。理论上计算了不同内径毛细管内等离子体压缩过程和收集效率，实验上采用极紫外探测器测量了毛细管内径对Xe气极紫外光源13.5 nm（2%带宽）辐射输出时间特性的影响，分析了毛细管内径对等离子状态的影响。结合该系统光学收集系统设计参数、不同内径毛细管收集效率和极紫外探测器信号强度，给出了不同内径毛细管中间焦点处13.5 nm（2%带宽）光功率比。结果表明：气压7 Pa、电流28 kA时，毛细管内径7 mm条件下，光源中间焦点处光功率最优化。

英文摘要：

The power of the 13.5 nm （2% bandwidth） emission is one of the key parameter for the EUV source. It′s important to study the temporary of the plasma in the capillary, which is useful to optimize the discharge structure and the EUV source power. In this paper, the pinch process of the plasma and the collection efficiency under different inner radiuses of the capillary were calculated theoretically. And the influence of the inner radius of the capillary on the dynamic condition of the 13.5 nm （2% bandwidth） emission was detected by a EUV monitor, which was used to analyze the influence of the inner radius of the capillary on the pinch process of the plasma. By combing the theoretical and experimental results with the design of collectors in this system, the 13.5 nm （2% bandwidth） emissions at the IF point were calculated under different inner radius of the capillary. The results show that the optimal of the power at the IF point has been got with the inner radius of the capillary 7 mm, the Xe gas pressure 7 Pa and discharge current 28 kA.