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Title: Fluorine negative ion density measurement in a dual frequency capacitive plasma etch reactor by cavity ring-down spectroscopy

Abstract

F{sup -} negative ions were detected by direct observation of the weak photodetachment absorption continuum below 364.5 nm by cavity ring-down spectroscopy. The negative ions were generated in a modified industrial dielectric plasma etch reactor, with 2+27 MHz dual frequency capacitive excitation in Ar/CF{sub 4}/O{sub 2} and Ar/C{sub 4}F{sub 8}/O{sub 2} gas mixtures. The F{sup -} signal was superimposed on an unidentified absorption continuum, which was diminished by O{sub 2} addition. The F{sup -} densities were in the range of (0.5-3)x10{sup 11} cm{sup -3}, and were not significantly different for single (27 MHz) or dual (2+27 MHz) frequency excitation, not confirming recent modeling predictions.

Authors:
; ; ; ; ;  [1];  [2]
  1. Laboratoire de Physique et Technologie des Plasmas, CNRS UMR 7648, Ecole Polytechnique, 91128 Palaiseau (France)
  2. (Slovakia)
Publication Date:
OSTI Identifier:
20778890
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 88; Journal Issue: 15; Other Information: DOI: 10.1063/1.2194823; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABSORPTION; ANIONS; ARGON; CARBON TETRAFLUORIDE; ELECTRON DETACHMENT; EXCITATION; FLUORINE IONS; MHZ RANGE 01-100; MIXTURES; OXYGEN; PLASMA; PLASMA DENSITY; PLASMA DIAGNOSTICS; SIMULATION; SPECTROSCOPY

Citation Formats

Booth, Jean-Paul, Corr, Cormac S., Curley, Garrett A., Jolly, Jacques, Guillon, Jean, Foeldes, Tomas, and Department of Experimental Physics, Comenius University, Bratislava, Slovakia 84248. Fluorine negative ion density measurement in a dual frequency capacitive plasma etch reactor by cavity ring-down spectroscopy. United States: N. p., 2006. Web. doi:10.1063/1.2194823.
Booth, Jean-Paul, Corr, Cormac S., Curley, Garrett A., Jolly, Jacques, Guillon, Jean, Foeldes, Tomas, & Department of Experimental Physics, Comenius University, Bratislava, Slovakia 84248. Fluorine negative ion density measurement in a dual frequency capacitive plasma etch reactor by cavity ring-down spectroscopy. United States. doi:10.1063/1.2194823.
Booth, Jean-Paul, Corr, Cormac S., Curley, Garrett A., Jolly, Jacques, Guillon, Jean, Foeldes, Tomas, and Department of Experimental Physics, Comenius University, Bratislava, Slovakia 84248. Mon . "Fluorine negative ion density measurement in a dual frequency capacitive plasma etch reactor by cavity ring-down spectroscopy". United States. doi:10.1063/1.2194823.
@article{osti_20778890,
title = {Fluorine negative ion density measurement in a dual frequency capacitive plasma etch reactor by cavity ring-down spectroscopy},
author = {Booth, Jean-Paul and Corr, Cormac S. and Curley, Garrett A. and Jolly, Jacques and Guillon, Jean and Foeldes, Tomas and Department of Experimental Physics, Comenius University, Bratislava, Slovakia 84248},
abstractNote = {F{sup -} negative ions were detected by direct observation of the weak photodetachment absorption continuum below 364.5 nm by cavity ring-down spectroscopy. The negative ions were generated in a modified industrial dielectric plasma etch reactor, with 2+27 MHz dual frequency capacitive excitation in Ar/CF{sub 4}/O{sub 2} and Ar/C{sub 4}F{sub 8}/O{sub 2} gas mixtures. The F{sup -} signal was superimposed on an unidentified absorption continuum, which was diminished by O{sub 2} addition. The F{sup -} densities were in the range of (0.5-3)x10{sup 11} cm{sup -3}, and were not significantly different for single (27 MHz) or dual (2+27 MHz) frequency excitation, not confirming recent modeling predictions.},
doi = {10.1063/1.2194823},
journal = {Applied Physics Letters},
number = 15,
volume = 88,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2006},
month = {Mon Apr 10 00:00:00 EDT 2006}
}
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