中国物理B ›› 2018, Vol. 27 ›› Issue (6): 65202-065202.doi: 10.1088/1674-1056/27/6/065202

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

Measurements of argon metastable density using the tunable diode laser absorption spectroscopy in Ar and Ar/O2

Dao-Man Han(韩道满), Yong-Xin Liu(刘永新), Fei Gao(高飞), Wen-Yao Liu(刘文耀), Jun Xu(徐军), You-Nian Wang(王友年)   

  1. 1 Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams(Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China;
    2 National Demonstration Center for Experimental Physics Education, Dalian University of Technology, Dalian 116024, China;
    3 North University of China, Taiyuan 030051, China
  • 收稿日期:2018-02-03 修回日期:2018-03-19 出版日期:2018-06-05 发布日期:2018-06-05
  • 通讯作者: Yong-Xin Liu E-mail:yxliu129@dlut.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos.11335004,11722541,11675039,and 11747153) and the Important National Science and Technology Specific Project,China (Grant No.2011ZX02403-001).

Measurements of argon metastable density using the tunable diode laser absorption spectroscopy in Ar and Ar/O2

Dao-Man Han(韩道满)1, Yong-Xin Liu(刘永新)1,2, Fei Gao(高飞)1, Wen-Yao Liu(刘文耀)3, Jun Xu(徐军)1, You-Nian Wang(王友年)1   

  1. 1 Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams(Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China;
    2 National Demonstration Center for Experimental Physics Education, Dalian University of Technology, Dalian 116024, China;
    3 North University of China, Taiyuan 030051, China
  • Received:2018-02-03 Revised:2018-03-19 Online:2018-06-05 Published:2018-06-05
  • Contact: Yong-Xin Liu E-mail:yxliu129@dlut.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos.11335004,11722541,11675039,and 11747153) and the Important National Science and Technology Specific Project,China (Grant No.2011ZX02403-001).

摘要:

Densities of Ar metastable states 1s5 and 1s3 are measured by using the tunable diode laser absorption spectroscopy (TDLAS) in Ar and Ar/O2 mixture dual-frequency capacitively coupled plasma (DF-CCP). We investigate the effects of high-frequency (HF, 60 MHz) power, low-frequency (LF, 2 MHz) power, and working pressure on the density of Ar metastable states for three different gas components (0%, 5%, and 10% oxygen mixed in argon). The dependence of Ar metastable state density on the oxygen content is also studied at different working pressures. It is found that densities of Ar metastable states in discharges with different gas components exhibit different behaviors as HF power increases. With the increase of HF power, the metastable density increases rapidly at the initial stage, and then tends to be saturated at a higher HF power. With a small fraction (5% or 10%) of oxygen added in argon plasma, a similar change of the Ar metastable density with HF power can be observed, but the metastable density is saturated at a higher HF power than in the pure argon discharge. In the DF-CCP, the metastable density is found to be higher than in a single frequency discharge, and has weak dependence on LF power. As working pressure increases, the metastable state density first increases and then decreases, and the pressure value, at which the density maximum occurs, decreases with oxygen content increasing. Besides, adding a small fraction of oxygen into argon plasma will significantly dwindle the metastable state density as a result of quenching loss by oxygen molecules.

关键词: argon metastable states, tunable diode laser absorption spectroscopy, capacitively coupled plasmas

Abstract:

Densities of Ar metastable states 1s5 and 1s3 are measured by using the tunable diode laser absorption spectroscopy (TDLAS) in Ar and Ar/O2 mixture dual-frequency capacitively coupled plasma (DF-CCP). We investigate the effects of high-frequency (HF, 60 MHz) power, low-frequency (LF, 2 MHz) power, and working pressure on the density of Ar metastable states for three different gas components (0%, 5%, and 10% oxygen mixed in argon). The dependence of Ar metastable state density on the oxygen content is also studied at different working pressures. It is found that densities of Ar metastable states in discharges with different gas components exhibit different behaviors as HF power increases. With the increase of HF power, the metastable density increases rapidly at the initial stage, and then tends to be saturated at a higher HF power. With a small fraction (5% or 10%) of oxygen added in argon plasma, a similar change of the Ar metastable density with HF power can be observed, but the metastable density is saturated at a higher HF power than in the pure argon discharge. In the DF-CCP, the metastable density is found to be higher than in a single frequency discharge, and has weak dependence on LF power. As working pressure increases, the metastable state density first increases and then decreases, and the pressure value, at which the density maximum occurs, decreases with oxygen content increasing. Besides, adding a small fraction of oxygen into argon plasma will significantly dwindle the metastable state density as a result of quenching loss by oxygen molecules.

Key words: argon metastable states, tunable diode laser absorption spectroscopy, capacitively coupled plasmas

中图分类号:  (Plasma diagnostic techniques and instrumentation)

  • 52.70.-m
52.70.Kz (Optical (ultraviolet, visible, infrared) measurements) 52.80.Vp (Discharge in vacuum)