›› 2014, Vol. 23 ›› Issue (7): 75202-075202.doi: 10.1088/1674-1056/23/7/075202

• PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES • 上一篇    下一篇

Mitigation of energetic ion debris from Gd plasma using dual laser pulses and the combined effect with ambient gas

窦银萍, 孙长凯, 刘超智, 高健, 郝作强, 林景全   

  1. School of Science, Changchun University of Science and Technology, Changchun 130022, China
  • 收稿日期:2013-10-21 修回日期:2014-01-02 出版日期:2014-07-15 发布日期:2014-07-15
  • 基金资助:
    Project supported by the National Basic Research Program of China (Grant No. 2013CB922404), the National Natural Science Foundation of China (Grant Nos. 11074027, 61178022, 11274053, and 11211120156), the Science & Technology Department of Jilin Province, China (Grant No. 20111812), the Research Fund for the Doctoral Program of Higher Education of China (Grant Nos. 20122216120009, 20122216110007, and 20112216120006), and the Young Scientists Fund of Changchun University of Science and Technology, China (Grant No. 000520).

Mitigation of energetic ion debris from Gd plasma using dual laser pulses and the combined effect with ambient gas

Dou Yin-Ping (窦银萍), Sun Chang-Kai (孙长凯), Liu Chao-Zhi (刘超智), Gao Jian (高健), Hao Zuo-Qiang (郝作强), Lin Jing-Quan (林景全)   

  1. School of Science, Changchun University of Science and Technology, Changchun 130022, China
  • Received:2013-10-21 Revised:2014-01-02 Online:2014-07-15 Published:2014-07-15
  • Contact: Sun Chang-Ka, Lin Jing-Quan E-mail:changkaisun@cust.edu.cn;linjingquan@cust.edu.cn
  • About author:52.38.-r; 52.59.Px; 52.59.Ye
  • Supported by:
    Project supported by the National Basic Research Program of China (Grant No. 2013CB922404), the National Natural Science Foundation of China (Grant Nos. 11074027, 61178022, 11274053, and 11211120156), the Science & Technology Department of Jilin Province, China (Grant No. 20111812), the Research Fund for the Doctoral Program of Higher Education of China (Grant Nos. 20122216120009, 20122216110007, and 20112216120006), and the Young Scientists Fund of Changchun University of Science and Technology, China (Grant No. 000520).

摘要: For the next-generation beyond extreme ultraviolet lithography (EUVL) sources, gadolinium (Gd) plasma with emission wavelength at 6.7 nm seems to be the leading candidate. Similar to the Sn target 13.5 nm light source, ion debris mitigation is one of the most important tasks in the laser-produced Gd plasma EUV source development. In this paper, a dual-laser-pulse scheme, which uses a low energy pulse to produce a pre-plasma and a main pulse after a time delay to shoot the pre-plasma, is employed to mitigate the energetic ion generation from the source. Optimal conditions (such as pre-pulse energy and wavelength, and the time delay between the pre-pulse and the main pulse for mitigating the ion energy) are experimentally obtained, and with the optimal conditions, the peak of the ion energy is found to be reduced to 1/18 of that of a single laser pulse case. Moreover, the combined effect by applying ambient gas to the dual-pulse scheme for ion debris mitigation is demonstrated, and the result shows that the yield of Gd ions is further reduced to around 1/9 of the value for the case with dual laser pulses.

关键词: extreme ultraviolet source, laser-induced plasma, Gd plasma, ion debris

Abstract: For the next-generation beyond extreme ultraviolet lithography (EUVL) sources, gadolinium (Gd) plasma with emission wavelength at 6.7 nm seems to be the leading candidate. Similar to the Sn target 13.5 nm light source, ion debris mitigation is one of the most important tasks in the laser-produced Gd plasma EUV source development. In this paper, a dual-laser-pulse scheme, which uses a low energy pulse to produce a pre-plasma and a main pulse after a time delay to shoot the pre-plasma, is employed to mitigate the energetic ion generation from the source. Optimal conditions (such as pre-pulse energy and wavelength, and the time delay between the pre-pulse and the main pulse for mitigating the ion energy) are experimentally obtained, and with the optimal conditions, the peak of the ion energy is found to be reduced to 1/18 of that of a single laser pulse case. Moreover, the combined effect by applying ambient gas to the dual-pulse scheme for ion debris mitigation is demonstrated, and the result shows that the yield of Gd ions is further reduced to around 1/9 of the value for the case with dual laser pulses.

Key words: extreme ultraviolet source, laser-induced plasma, Gd plasma, ion debris

中图分类号:  (Laser-plasma interactions)

  • 52.38.-r
52.59.Px (Hard X-ray sources) 52.59.Ye (Plasma devices for generation of coherent radiation ?)