skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Experimental and numerical investigations of the phase-shift effect in capacitively coupled discharges

Abstract

The phase-shift effect has been investigated by a Langmuir probe and a fluid model in Ar capacitively coupled plasmas at 50 mTorr. In the discharge, two sources with the same frequency, i.e., 27.12 MHz, are applied on the top and bottom electrodes simultaneously, and the phase shift between them varies from 0 to π. It is found that the electron density has an off-axis peak near the radial edge when the phase difference is equal to 0 due to the electrostatic edge effect, and the best radial uniformity is observed at a phase difference equal to π. Furthermore, when the voltage increases, the best radial uniformity is obtained at lower phase shift values. Moreover, the electron energy probability function has a bi-temperature structure at all the selected phase differences at r = 1–15 cm. The evolution of the plasma characteristics with the phase difference implies that the best radial uniformity can be obtained, by balancing the electrostatic edge effect and the phase shift effect.

Authors:
; ; ;  [1]
  1. Key Laboratory of Materials Modification by Laser, Ion, and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
Publication Date:
OSTI Identifier:
22303807
Resource Type:
Journal Article
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 21; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTRIC POTENTIAL; ELECTRODES; ELECTRON DENSITY; ELECTRONS; LANGMUIR PROBE; MHZ RANGE 01-100; PHASE SHIFT; PLASMA

Citation Formats

Gao, Fei, Zhang, Yu-Ru, Zhao, Shu-Xia, and Wang, You-Nian. Experimental and numerical investigations of the phase-shift effect in capacitively coupled discharges. United States: N. p., 2014. Web. doi:10.1063/1.4892948.
Gao, Fei, Zhang, Yu-Ru, Zhao, Shu-Xia, & Wang, You-Nian. Experimental and numerical investigations of the phase-shift effect in capacitively coupled discharges. United States. https://doi.org/10.1063/1.4892948
Gao, Fei, Zhang, Yu-Ru, Zhao, Shu-Xia, and Wang, You-Nian. 2014. "Experimental and numerical investigations of the phase-shift effect in capacitively coupled discharges". United States. https://doi.org/10.1063/1.4892948.
@article{osti_22303807,
title = {Experimental and numerical investigations of the phase-shift effect in capacitively coupled discharges},
author = {Gao, Fei and Zhang, Yu-Ru and Zhao, Shu-Xia and Wang, You-Nian},
abstractNote = {The phase-shift effect has been investigated by a Langmuir probe and a fluid model in Ar capacitively coupled plasmas at 50 mTorr. In the discharge, two sources with the same frequency, i.e., 27.12 MHz, are applied on the top and bottom electrodes simultaneously, and the phase shift between them varies from 0 to π. It is found that the electron density has an off-axis peak near the radial edge when the phase difference is equal to 0 due to the electrostatic edge effect, and the best radial uniformity is observed at a phase difference equal to π. Furthermore, when the voltage increases, the best radial uniformity is obtained at lower phase shift values. Moreover, the electron energy probability function has a bi-temperature structure at all the selected phase differences at r = 1–15 cm. The evolution of the plasma characteristics with the phase difference implies that the best radial uniformity can be obtained, by balancing the electrostatic edge effect and the phase shift effect.},
doi = {10.1063/1.4892948},
url = {https://www.osti.gov/biblio/22303807}, journal = {Physics of Plasmas},
issn = {1070-664X},
number = 8,
volume = 21,
place = {United States},
year = {Fri Aug 15 00:00:00 EDT 2014},
month = {Fri Aug 15 00:00:00 EDT 2014}
}