中国物理B ›› 2018, Vol. 27 ›› Issue (12): 124701-124701.doi: 10.1088/1674-1056/27/12/124701

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Gas flow characteristics of argon inductively coupled plasma and advections of plasma species under incompressible and compressible flows

Shu-Xia Zhao(赵书霞), Zhao Feng(丰曌)   

  1. Physics Department, Dalian University of Technology, Dalian 116024, China
  • 收稿日期:2018-06-07 修回日期:2018-10-03 出版日期:2018-12-05 发布日期:2018-12-05
  • 通讯作者: Shu-Xia Zhao E-mail:zhaonie@dlut.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundations of China (Grant No. 11305023). The author is deeply indebted to the Dalian University of Technology for providing the authority of utilizing the COMSOL software.

Gas flow characteristics of argon inductively coupled plasma and advections of plasma species under incompressible and compressible flows

Shu-Xia Zhao(赵书霞), Zhao Feng(丰曌)   

  1. Physics Department, Dalian University of Technology, Dalian 116024, China
  • Received:2018-06-07 Revised:2018-10-03 Online:2018-12-05 Published:2018-12-05
  • Contact: Shu-Xia Zhao E-mail:zhaonie@dlut.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundations of China (Grant No. 11305023). The author is deeply indebted to the Dalian University of Technology for providing the authority of utilizing the COMSOL software.

摘要:

In this work, incompressible and compressible flows of background gas are characterized in argon inductively coupled plasma by using a fluid model, and the respective influence of the two flows on the plasma properties is specified. In the incompressible flow, only the velocity variable is calculated, while in the compressible flow, both the velocity and density variables are calculated. The compressible flow is more realistic; nevertheless, a comparison of the two types of flow is convenient for people to investigate the respective role of velocity and density variables. The peripheral symmetric profile of metastable density near the chamber sidewall is broken in the incompressible flow. At the compressible flow, the electron density increases and the electron temperature decreases. Meanwhile, the metastable density peak shifts to the dielectric window from the discharge center, besides for the peripheral density profile distortion, similar to the incompressible flow. The velocity profile at incompressible flow is not altered when changing the inlet velocity, whereas clear peak shift of velocity profile from the inlet to the outlet at compressible flow is observed as increasing the gas flow rate. The shift of velocity peak is more obvious at low pressures for it is easy to compress the rarefied gas. The velocity profile variations at compressible flow show people the concrete residing processes of background molecule and plasma species in the chamber at different flow rates. Of more significance is it implied that in the usual linear method that people use to calculate the residence time, one important parameter in the gas flow dynamics, needs to be rectified. The spatial profile of pressure simulated exhibits obvious spatial gradient. This is helpful for experimentalists to understand their gas pressure measurements that are always taken at the chamber outlet. At the end, the work specification and limitations are listed.

关键词: gas flow, inductively coupled plasma, compressible flow, fluid model

Abstract:

In this work, incompressible and compressible flows of background gas are characterized in argon inductively coupled plasma by using a fluid model, and the respective influence of the two flows on the plasma properties is specified. In the incompressible flow, only the velocity variable is calculated, while in the compressible flow, both the velocity and density variables are calculated. The compressible flow is more realistic; nevertheless, a comparison of the two types of flow is convenient for people to investigate the respective role of velocity and density variables. The peripheral symmetric profile of metastable density near the chamber sidewall is broken in the incompressible flow. At the compressible flow, the electron density increases and the electron temperature decreases. Meanwhile, the metastable density peak shifts to the dielectric window from the discharge center, besides for the peripheral density profile distortion, similar to the incompressible flow. The velocity profile at incompressible flow is not altered when changing the inlet velocity, whereas clear peak shift of velocity profile from the inlet to the outlet at compressible flow is observed as increasing the gas flow rate. The shift of velocity peak is more obvious at low pressures for it is easy to compress the rarefied gas. The velocity profile variations at compressible flow show people the concrete residing processes of background molecule and plasma species in the chamber at different flow rates. Of more significance is it implied that in the usual linear method that people use to calculate the residence time, one important parameter in the gas flow dynamics, needs to be rectified. The spatial profile of pressure simulated exhibits obvious spatial gradient. This is helpful for experimentalists to understand their gas pressure measurements that are always taken at the chamber outlet. At the end, the work specification and limitations are listed.

Key words: gas flow, inductively coupled plasma, compressible flow, fluid model

中图分类号:  (Navier-Stokes equations)

  • 47.10.ad
47.11.Fg (Finite element methods) 47.15.-x (Laminar flows) 52.30.Ex (Two-fluid and multi-fluid plasmas)