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Title: Electric probe investigations of microwave generated, atmospheric pressure, plasma jets

Abstract

We examine the applicability of the Langmuir-type of characterization for atmospheric pressure plasma jets generated in a millimeter-size cavity microwave resonator at 2.45 GHz. Wide range I-V characteristics of helium, argon, nitrogen, air and oxygen are presented for different gas fluxes, distances probe-resonator, and microwave powers. A detailed analysis is performed for the fine variation in the current around the floating potential. A simplified theory specially developed for this case is presented, considering the ionic and electronic saturation currents and the floating potential. Based on this theory, we conclude that, while the charge carrier density depends on gas flow, distance to plasma source, and microwave absorbed power, the electron temperature is quite independent of these parameters. The resulting plasma parameters for helium, argon, and nitrogen are presented.

Authors:
; ;  [1]
  1. Microwave Department, Ferdinand-Braun-Institut, Leibniz-Institut fuer Hoechstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)
Publication Date:
OSTI Identifier:
21476338
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 108; Journal Issue: 1; Other Information: DOI: 10.1063/1.3448034; (c) 2010 American Institute of Physics
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AIR; ARGON; ATMOSPHERIC PRESSURE; CAVITY RESONATORS; CHARGE CARRIERS; ELECTRIC CONDUCTIVITY; ELECTRON TEMPERATURE; GHZ RANGE; HELIUM; ION TEMPERATURE; LANGMUIR PROBE; NITROGEN; OXYGEN; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; PLASMA JETS; PLASMA POTENTIAL; ELECTRIC POTENTIAL; ELECTRIC PROBES; ELECTRICAL PROPERTIES; ELECTRONIC EQUIPMENT; ELEMENTS; EQUIPMENT; FLUIDS; FREQUENCY RANGE; GASES; NONMETALS; PHYSICAL PROPERTIES; PROBES; RARE GASES; RESONATORS

Citation Formats

Porteanu, H. E., Kuehn, S., and Gesche, R. Electric probe investigations of microwave generated, atmospheric pressure, plasma jets. United States: N. p., 2010. Web. doi:10.1063/1.3448034.
Porteanu, H. E., Kuehn, S., & Gesche, R. Electric probe investigations of microwave generated, atmospheric pressure, plasma jets. United States. doi:10.1063/1.3448034.
Porteanu, H. E., Kuehn, S., and Gesche, R. Thu . "Electric probe investigations of microwave generated, atmospheric pressure, plasma jets". United States. doi:10.1063/1.3448034.
@article{osti_21476338,
title = {Electric probe investigations of microwave generated, atmospheric pressure, plasma jets},
author = {Porteanu, H. E. and Kuehn, S. and Gesche, R.},
abstractNote = {We examine the applicability of the Langmuir-type of characterization for atmospheric pressure plasma jets generated in a millimeter-size cavity microwave resonator at 2.45 GHz. Wide range I-V characteristics of helium, argon, nitrogen, air and oxygen are presented for different gas fluxes, distances probe-resonator, and microwave powers. A detailed analysis is performed for the fine variation in the current around the floating potential. A simplified theory specially developed for this case is presented, considering the ionic and electronic saturation currents and the floating potential. Based on this theory, we conclude that, while the charge carrier density depends on gas flow, distance to plasma source, and microwave absorbed power, the electron temperature is quite independent of these parameters. The resulting plasma parameters for helium, argon, and nitrogen are presented.},
doi = {10.1063/1.3448034},
journal = {Journal of Applied Physics},
number = 1,
volume = 108,
place = {United States},
year = {Thu Jul 15 00:00:00 EDT 2010},
month = {Thu Jul 15 00:00:00 EDT 2010}
}
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