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Plasma Chemistry and Plasma Processing

, Volume 17, Issue 2, pp 193–206 | Cite as

Characterization of an argon-hydrogen microwave discharge used as an atomic hydrogen source. Effect of hydrogen dilution on the atomic hydrogen production

  • L. Thomas
  • J. L. Jauberteau
  • I. Jauberteau
  • J. Aubreton
  • A. Catherinot
Article

Abstract

This work is devoted to the study of an argon-hydrogen microwave plasma used as an atomic hydrogen source. Our attention has focused on the effect of the hydrogen dilution in argon on atomic hydrogen production. Diagnostics are performed either in the discharge or in the post-discharge using emission spectroscopy (actinometry) and mass spectrometry. The agreement between actinometry and mass spectrometry diagnostics proves that actinometry on the Ha(656.3 nm) and Hβ(486.1 nm) hydrogen Balmer lines can be used to measure the relative atomic hydrogen density within the microwave discharge. Results show that the atomic hydrogen density is maximum for a gas mixture corresponding to the partial pressure ratioP H 2/P Ar range between 1.5 and 2. The variation of atomic hydrogen density can be explained by a change of the dominant reactive mechanisms. At a low hydrogen partial pressure the dominant processes are the charge transfers with recombinations between Ar+ and H2 which lead to ArH+ and H 2 + ion formation. Both ions are dissociated in dissociative electron attachment processes. At a low argon partial pressure the electron temperature and the electron density decrease with increasing partial pressure ratio. The dominant mechanisms become direct reactions between charged particles (e, H+, H 2 + , and H 3 + ) or excited species H(n=2) with H2 producing H atoms.

Key words

Atomic hydrogen source microwave plasma optical spectroscopy mass spectrometry 

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References

  1. 1.
    A. Granier, S. Pasquier, C. Boisse-Laporte, R. Darchicourt, P. Leprince, and J. Marec,J. Phys. D: Appl. Phys. 22, 1487 (1989).CrossRefADSGoogle Scholar
  2. 2.
    A. Donnelly, M. P. Hughes, J. Geddes, and H. B. Gilbody,Meas. Sci. Technol. 3, 528 (1992).CrossRefADSGoogle Scholar
  3. 3.
    R. W. McCullough, J. Geddes, A. Donnelly, M. Liehr, M. P. Hughes, and H. B. Gilbody,Meas. Sci. Technol. 4, 79 (1993).CrossRefADSGoogle Scholar
  4. 4.
    C. Pecker-Wimel,Introduction à la spectroscopie des plasmas, Gordon and Breach (1967).Google Scholar
  5. 5.
    A. Rousseau, L. Tomassi, C. Boisse-Laporte, G. Gousset, and P. Leprince, Proc. Escampig 94, Noordwijkerhout, The Netherlands, August 23–26, 1994, European Physical Society (1994), pp. 436–437.Google Scholar
  6. 6.
    A. Rousseau, E. Bluem, A. Granier, P. Leprince, and J. Marec, Proc. Escampig 92, St. Petersburg, Russia, August 25–28, 1992, European Physical Society (1992), pp. 97–98.Google Scholar
  7. 7.
    J. Roboz,Introduction to Mass Spectrometry, Interscience, New York (1984).Google Scholar
  8. 8.
    L. Thomas, PhD thesis, Limoges University (1993).Google Scholar
  9. 9.
    J. Geddes, R. W. McCullough, A. Donnelly, and H. B. Gilbody,Plasma Sources Sci. Technol. 2, 93–99 (1993).CrossRefADSGoogle Scholar
  10. 10.
    A. Rousseau, E. Bluem, A. Granier, C. Boisse-Laporte, G. Gousset, and P. Leprince, Proc. 11th ISPC, Loughborough, Great Britain, August 1993, Heberlein (1993), p. 234.Google Scholar
  11. 11.
    M. J. de Graaf, R. P. Dahiya, J. L. Jauberteau, F. J. de Hoog, M. J. F. van de Sande, and D. C. Schram,Colloq. Phys. 51, C5-387 (1990).Google Scholar
  12. 12.
    D. K. Otorbaev, A. J. M. Buuron, N. T. Guerassimov, M. C. M. van de Sanden, and D. C. Schram,J. Appl. Phys. 76, 4499 (1994).CrossRefADSGoogle Scholar

Copyright information

© Plenum Publishing Corporation 1997

Authors and Affiliations

  • L. Thomas
    • 1
  • J. L. Jauberteau
    • 1
  • I. Jauberteau
    • 1
  • J. Aubreton
    • 1
  • A. Catherinot
    • 1
  1. 1.URA 320 CNRS, UER des SciencesLimogesFrance

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