Share This Article:

Remote Plasma Maintenance in Low-Pressure Discharges with an External Magnetic Field

Abstract Full-Text HTML Download Download as PDF (Size:1552KB) PP. 1616-1625
DOI: 10.4236/jmp.2012.330199    3,306 Downloads   5,177 Views   Citations

ABSTRACT

The spatial structure of remote plasma regions in rf discharges is analyzed based on a 2D model of free-fall regime discharge maintenance. Since the study is directed towards description of the magnetic filter region in the tandem plasma sources of negative hydrogen ions, hydrogen discharges are considered, with a weak magnetic field located outside the region of the rf power deposition. With the formation of different regions in the discharge—the rf power deposition region, the region with electron magnetization, the transition between them and the region behind the filter—the results display superimposed effects of nonlocal discharge maintenance without and with a magnetic field. Slight decrease of the electron temperature accompanied with strong drop of the electron density is the “pure” effect of the plasma expansion in regions without external magnetic field. Strong drop of the electron temperature accompanied with formation of a maximum of the electron density in the filter region is the “pure” effect of the plasma expansion through a magnetic field. Based on the results for the spatial distribution of the electron density and temperature obtained with shifting the position of the magnetic filter, optimization of the source regarding high yield of volume-produced negative ions is discussed.

Conflicts of Interest

The authors declare no conflicts of interest.

Cite this paper

S. Lishev, A. Shivarova and K. Tarnev, "Remote Plasma Maintenance in Low-Pressure Discharges with an External Magnetic Field," Journal of Modern Physics, Vol. 3 No. 10A, 2012, pp. 1616-1625. doi: 10.4236/jmp.2012.330199.

References

[1] M. J. Kushner, “Plasma Chemistry of He/O2/SiH4 and He/N2O/SiH4Mixtures for Remote Plasma-Activated Chemical-Vapor Deposition of Silicon Dioxide,” Journal of Applied Physics, Vol. 74, No. 11, 1993, pp. 6538-6553. doi:10.1063/1.355115
[2] D. P. Lymberopoulos and D. J. Economou, “Two-Dimensional Self-Consistent Radio Frequency Plasma Simulations Relevant to the Gaseous Electronics Conference RF Reference Cell,” Journal of Research of the National Institute of Standards and Technology, Vol. 100, No. 4, 1995, pp. 473-494. doi:10.6028/jres.100.036
[3] M. J. Kushner, “Hybrid Modelling of Low Temperature Plasmas for Fundamental Investigations and Equipment Design,” Journal of Physics D: Applied Physics, Vol. 42, 2009, Article ID: 194013.
[4] E. Speth, H. D. Falter, P. Franzen, U. Fantz, M. Bandyopadhyay, S. Christ, A. Encheva, M. Froschle, D. Holtum, B. Heinemann, W. Kraus, A. Lorenz, Ch. Martens, P. McNeely, S. Obermayer, R. Riedl, R. Suss, A. Tanga, R. Wilchelm and D. Wünderlich, “Overview of the RF Source Development Programme at IPP Garching,” Nuclear Fusion, Vol. 46, No. 6, 2006, pp. S220-S238. doi:10.1088/0029-5515/46/6/S03
[5] Ts. V. Paunska, A. P. Shivarova, Kh. Ts. Tarnev and Ts. V. Tsankov, “2D Model of a Tandem Plasma Source: The Role of the Transport Processes,” AIP Conference Proceedings, Vol. 1097, 1997, pp. 12-21.
[6] M. Bacal, “Physics Aspects of Negative Ion Sources,” Nuclear Fusion, Vol. 46, No. 6, 2006, pp. S250-S259. doi:10.1088/0029-5515/46/6/S05
[7] A. J. T. Holmes, “Electron Flow through Transverse Magnetic Fields in Magnetic Multipole Arc Discharges,” Review of Scientific Instruments, Vol. 53, No. 10, 1982, pp. 1517-1522. doi:10.1063/1.1136828
[8] A. J. T. Holmes, “Electron Cooling in Magnetic Multipole Arc Discharges,” Review of Scientific Instruments, Vol. 53, No. 10, 1982, pp. 1523-1526. doi:10.1063/1.1136829
[9] F. A. Haas, L. M. Lea and A. J. T. Holmes, “A ‘Hydrodinamic’, Model of the Negatice-Ion Source,” Journal of Physics D: Applied Physics, Vol. 24, No. 9, 1991, pp. 1541-1550. doi:10.1088/0022-3727/24/9/005
[10] A. J. T. Holmes, R. McAdams, G . Proudfoot, S. Cox, E. Surrey and R. King, “Intense Negative Ion Sources at Culham Laboratory,” Review of Scientific Instruments, Vol. 65, No. 4, 1994, pp. 1153-1158. doi:10.1063/1.1145043
[11] M. Shirai, M. Ogasawara, T. Koishimine and A. Hatayama, “Theoretical Investigations of Electron Temperature Variation across Magnetic Filter in a Negative Ion Source,” Review of Scientific Instruments, Vol. 67, No. 3, 1996, pp. 1085-1087. doi:10.1063/1.1147230
[12] A. J. T. Holmes, “A One-Dimensional Model of a Negative Ion Source,” Plasma Sources Science and Technology, Vol. 5, No. 3, 1996, pp. 453-473. doi:10.1088/0963-0252/5/3/014
[13] K. Ohi, H. Naitou, Y. Tauchi and O. Fukumasa, “Observation of the Limit Cycle in Symmetric Plasma Divided by a Magnetic Filter,” Physics of Plasmas, Vol. 8, No. 1, 2001, pp. 23-30. doi:10.1063/1.1329653
[14] T. Mizuno, Y. Kitade, A. Hatayama, T. Sakurabayashi, N. Imai, T. Miroshita and T. Inoue, “Numerical Analysis of Plasma Spatial Uniformity in Negative Ion Sources by a Fluid Model,” Review of Scientific Instruments, Vol. 75, No. 5, 2004, pp. 1760-1763. doi:10.1063/1.1695622
[15] H. Naitou, K. Ohi and O. Fukumasa, “Beam Instability Excited by the Magnetic Filter,” Review of Scientific Instruments, Vol. 71, No. 2, 2000, pp. 875-877. doi:10.1063/1.1150318
[16] St. Kolev, St. Lishev, A. Shivarova, Kh. Tarnev and R. Wilhelm, “Magnetic Filter Operation in Hydrogen Plasmas,” Plasma Physics and Controlled Fusion, Vol. 49, No. 9, 2007, pp. 1349-1369. doi:10.1088/0741-3335/49/9/001
[17] St. Kolev, G. J. M. Hagelaar and J. P. Boeuf, “Particle-in-Cell with Monte Carlo Collision Modeling of the Electron and Negative Hydrogen Ion Transport across a Localized Transverse Magnetic Field,” Physics of Plasmas, Vol. 16, 2009, Article ID: 042318.
[18] G. J. M. Hagelaar and N. Oudini, “Plasma Transport across Magnetic Field Lines in Low-Temperature Plasma Sources,” Plasma Physics and Controlled Fusion, Vol. 53, No. 12, 2011, Article ID: 124032.
[19] St. St. Lishev, A. P. Shivarova and Ts. V. Tsankov, “Experiments on the Detection of Negative Hydrogen Ions in a Small-Size Tandem Plasma Source,” AIP Conference Proceedings, Vol. 1097, 2009, pp. 127-136. doi:10.1063/1.3112505
[20] St. St. Lishev and A. P. Shivarova, “Laser-Photodetachment and Faraday-Cup Measurements in the Expansion Region of a Tandem-Type Plasma Source,” AIP Conference Proceedings, Vol. 1390, 2011, pp. 192-201.
[21] R. K. Janev, W. D. Langer, K. Evans Jr. and D. E. Post Jr., “Elementary Processes in Hydrogen-Helium Plasmas,” Springer, Berlin, 1987.
[22] R. H. Neynaber and S. M. Trujillo, “Study of H2+ + H3 → H2+ + H Using Merging Beams,” Physical Review, Vol. 167, No. 1, 1968, pp. 63-67. doi:10.1103/PhysRev.167.63
[23] A. Rousseau, A. Granier, G. Gousset and P. Leprince, “Microwave Discharge in H2: Influence of H-Atom Den- sity on the Power Balance,” Journal of Physics D: Applied Physics, Vol. 27, No. 7, 1994, pp. 1412-1422. doi:10.1088/0022-3727/27/7/012
[24] I. Koleva, Ts. Paunska, H. Schluter, A. Shivarova and Kh. Tarnev, “Surface-Wave Produced Discharges in Hydrogen: I. Self-Consistent Model of Diffusion-Controlled Discharges,” Plasma Sources Science and Technology, Vol. 12, No. 4, 2003, pp. 597-607. doi:10.1088/0963-0252/12/4/311
[25] St. Lishev, A. Shivarova and Kh. Tarnev, “On the Inertia Term in the Momentum Equation in the Free-Fall Regime of Discharge Maintenance,” Journal of Plasma Physics, Vol. 77, No. 4, 2011, pp. 469-478. doi:10.1017/S0022377810000620
[26] S. Weissman and E. A. Mason, “Estimation of the Mutual Diffusion Coefficient of Hydrogen Atoms and Molecules,” Journal of Chemical Physics, Vol. 36, No. 3, 1962, pp. 794-797. doi:10.1063/1.1732612

  
comments powered by Disqus

Copyright © 2019 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.