Model of a surface-wave discharge at atmospheric pressure with a fixed profile of the gas temperature

19th International Summer School on Vacuum, Electron and Ion Technologies

Nikovski, M.^1 ; Kiss'Ovski, Zh.^1 ; Tatarova, E.^2

Faculty of Physics, St. Kl. Ohridski University of Sofia, 5 J Bourchier blvd., Sofia

1164, Bulgaria^1

Institute of Plasmas and Nuclear Fusion, Instituto Superior Técnico, University of Lisbon, Lisbon

1049-001, Portugal^2

关键词: Collisional radiative model;    Dispersion relations;    Electron energies;    Excited molecules;    Local approximation;    Surface wave discharge;    Surface-wave-sustained discharges;    Symmetric surface wave;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/700/1/012014/pdf
DOI  :  10.1088/1742-6596/700/1/012014

来源: IOP

【 摘 要 】

We present a 3D model of a surface-wave-sustained discharge at 2.45 GHz at atmospheric pressure. A small plasma source creates a plasma column in a dielectric tube and a plasma torch is observed above the top. The plasma parameters and the axial profile of the gas temperature are significantly changed in the presence of the substrate above the plasma torch. The Boltzmann equation for electrons under the local approximation is solved, together with the heavy particle balance equations at a fixed axial profile of the gas temperature. The model of this finite length plasma column includes also the dispersion relation of azimuthally-symmetric surface waves. A detailed collisional-radiative model is also implemented for argon discharge at atmospheric pressure, which includes 21 rate balance equations for excited Ar atoms [(Ar(1s5-1s2), Ar(2p10-2p1), Ar(2s3d), Ar(3p)], for positive Ar+and Ar2+ions and for excited molecules. The changes in the EEDF shape and the mean electron energy along the plasma column are investigated and the axial structures of the discharge and plasma parameters are obtained.