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Title: Two-dimensional electromagnetic model of a microwave plasma reactor operated by an axial injection torch

Abstract

This paper presents a two-dimensional electromagnetic model for a microwave (2.45 GHz) plasma reactor operated by an axial injection torch. The model solves Maxwell's equations, adopting a harmonic time description and considering the collision dispersion features of the plasma. Perfect-conductor boundary conditions are satisfied at the reactor walls, and absorbing boundary conditions are used at the open end of the coaxial waveguide powering the system. Simulations yield the distribution of the electromagnetic fields and the average power absorbed by the system for a given spatial profile of the plasma density (tailored from previous experimental measurements), with maximum values in the range 10{sup 14}-10{sup 15} cm{sup -3}. Model results reveal that the system exhibits features similar to those of an air-filled, one-end-shorted circular metal waveguide, supporting evanescent or oscillatory solutions for radial dimensions below or above a critical radius, respectively. Results also show that the fractional average power absorbed by the plasma is strongly influenced by the system dimensions, which play a major role in defining the geometry pattern of the electromagnetic field distribution. Simulations are used to provide general guidelines for device optimization.

Authors:
;  [1]
  1. Centro de Fisica dos Plasmas, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal)
Publication Date:
OSTI Identifier:
20982877
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 10; Other Information: DOI: 10.1063/1.2732508; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AIR; BEAM INJECTION; BOUNDARY CONDITIONS; ELECTROMAGNETIC FIELDS; GEOMETRY; GHZ RANGE 01-100; MATHEMATICAL SOLUTIONS; MAXWELL EQUATIONS; MICROWAVE RADIATION; OPTIMIZATION; PLASMA; PLASMA DENSITY; PLASMA SIMULATION; TWO-DIMENSIONAL CALCULATIONS; WAVEGUIDES

Citation Formats

Alvarez, R., and Alves, L. L. Two-dimensional electromagnetic model of a microwave plasma reactor operated by an axial injection torch. United States: N. p., 2007. Web. doi:10.1063/1.2732508.
Alvarez, R., & Alves, L. L. Two-dimensional electromagnetic model of a microwave plasma reactor operated by an axial injection torch. United States. doi:10.1063/1.2732508.
Alvarez, R., and Alves, L. L. Tue . "Two-dimensional electromagnetic model of a microwave plasma reactor operated by an axial injection torch". United States. doi:10.1063/1.2732508.
@article{osti_20982877,
title = {Two-dimensional electromagnetic model of a microwave plasma reactor operated by an axial injection torch},
author = {Alvarez, R. and Alves, L. L.},
abstractNote = {This paper presents a two-dimensional electromagnetic model for a microwave (2.45 GHz) plasma reactor operated by an axial injection torch. The model solves Maxwell's equations, adopting a harmonic time description and considering the collision dispersion features of the plasma. Perfect-conductor boundary conditions are satisfied at the reactor walls, and absorbing boundary conditions are used at the open end of the coaxial waveguide powering the system. Simulations yield the distribution of the electromagnetic fields and the average power absorbed by the system for a given spatial profile of the plasma density (tailored from previous experimental measurements), with maximum values in the range 10{sup 14}-10{sup 15} cm{sup -3}. Model results reveal that the system exhibits features similar to those of an air-filled, one-end-shorted circular metal waveguide, supporting evanescent or oscillatory solutions for radial dimensions below or above a critical radius, respectively. Results also show that the fractional average power absorbed by the plasma is strongly influenced by the system dimensions, which play a major role in defining the geometry pattern of the electromagnetic field distribution. Simulations are used to provide general guidelines for device optimization.},
doi = {10.1063/1.2732508},
journal = {Journal of Applied Physics},
number = 10,
volume = 101,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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