Investigation of a radio-frequency capacitive sheath and the effect of DC bias control on the power absorption at low pressures

POSTER

Abstract

Many of today's processing plasma tools are operated at low pressures to achieve high etch directivity and reduce side erosion on the wafer. At these pressures electron-neutral collisions are rare and the electrons cannot gain energy through the Ohmic heating process. Instead the heating mechanism is attributed to a stochastic process between the electrons and the sheath electric field. Theoretical models of this stochastic process include the hard wall approximation and the pressure heating effect. The former is inconsistent with electron current conservation in the sheath whilst the latter shows a difference in power absorption when the electron loss to the electrodes is considered. This paper examines the effects of electron current of a capacitive sheath by controlling this current with an additional DC bias. Experimental and particle-in-cell model results for a low pressure argon plasma are compared and presented. Results show that the electron power absorption is more effective when the electron conduction current is removed. The model also shows a high harmonic content on the sheath voltage which is attenuated by removing the electron current. These high frequency harmonics are measured in the experiment with a floating probe and their correlation with the electron current is in agreement with the model results.

Authors

  • Paule Maguire

    Department of Chemistry and Physics, Lamar University, Applied Materials, Sandia National Laboratories, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, D-44780 Bochum, Germany, Ecole Polytechnique, France, Assistant Research Professor, University of Saskatchewan, PPPL, University of Saskatchewan, Saskatoon, Canada, Plasma Physics Laboratory, Princeton University, Technische Universiteit Eindhoven, Institut fur Niedertemperatur Plasmaphysik, Old Dominion University, Norfolk, VA 23529, Korea Advanced Institute of Science and Technology \& New York University, Korea Advanced Institute of Science and Technology, St.Petersburg State Politechnical University, St.Petersburg, Russia, Hanyang University, University of Nantes, Eindhoven University of Technology, Universidad Nacional Autonoma de Mexico, Air Force Research Laboratory, Innovative Scientific Solutions, Inc, University of Cambridge, UK, University of Bristol, UK, University Kiel, Germany, INP Greifswald, Germany, KRISS, INP, Greifswald, Germany, Australian National University, Drake University, University of Central Florida, University of Missouri-Rolla, John Carroll University, Indiana University-Purdue University Fort Wayne, University of Southampton, UK and Hong Kong Polytechnic University, University of Nottingham, UK, University of Pittsburgh, Department of Physics, Pittsburgh, PA 15260, Department of Computer Science, Lamar University, Institute of Nuclear Physics, Moscow State University, Russia, Univ. of Houston, Dublin City University, Ireland, West Virginia University, Nagoya Institute of Technology, National University of Ireland, Maynooth, 3M Company, Samsung Electronics, Kyoto University, EM2C, Ecole Centrale, CNRS, Chatenay, France, University of Duisburg-Essen, Ruhr Uni Bochum, LSP, UJF, CNRS, Grenoble, France, Lawrence Berkeley National Laboratory, Tech-X Corporation, Dublin City University, Princeton Plasma Physics Laboratory, Plasma Physics Division, Naval Research Laboratory, The Open University, United Kingdom, Eindhoven University of Technology, The Netherlands, University of Minnesota, Universit\'e Joseph Fourier de Grenoble, France, Nagoya University, Japan, West Virginia University, Physics Department, Morgantown, WV 26506-6315, Dept. of Physics and Astronomy, The Open University, Milton Keynes, UK, Institute for Plasma and Atomic Physics, CPST, Ruhr-University Bochum, Germany, CAMS, Australian National University, Schuster Laboratory, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK, Centre for Antimatter-Matter Studies, Griffith University, ISAS/JAXA, University of Tokyo, Department of Aeronautics and Astronautics, Kyoto University, Kyoto, Japan, University of Texas at Austin, LTM, Grenoble, LSP, Grenoble, CPAT,Toulouse, LPGP, Orsay, France, NRL-NRC Postdoctoral Associate, SFA, Crofton, MD, Center for Plasma Science and Technology CPST, Ruhr University Bochum, D-44780 Bochum, Germany, Department of Physics, University Duisburg-Essen, D-45141 Essen, Germany, LACE, UCBL, CNRS, Lyon, France, LPTP, Ecole Polytechnique, CNRS, Palaiseau, France, Air Force Research Laboratory, Wright-Patterson AFB, OH, UES, INC., Dayton, OH, St. Petersburg State University, St. Petersburg, Russia, Suzuka National College of Technology, Japan, Plasma Research Laboratory, NCPST, Dublin City University, Dublin 9, Ireland, University Greifswald, Germany, Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Nagoya University, University of Liverpool, United Kingdom, LPTP, Ecole Polytechnique, Palaiseau, France, Laboratory for Optical Physics and Engineering, Dept. of Elec. and Computer Engr., University of Illinois, Laboratory for Optical Physics and Engineering, Dept. of Elect. and Computer Engr., University of Illinois, The Ohio State University (OH), Department of Physics, University of Rajshahi, Rajshahi, Bangladesh, CAMS, Murdoch University, Australia, Drake University, USA, Gothenburg University, University of Wisconsin- Madison, University of Wisconsin-Madison, Physics Dept., Sophia University, Chiyoda-ku, Tokyo 102-855, Japan, ARC Centre for Antimatter-Matter Studies, SoCPES, Flinders University, GPO Box 2100, Adelaide, 5001 Australia, Korea Advanced Institute of Science and Technology / New York University, National Fusion Research Center / Korea Advanced Institute of Science and Technology, Korea Advanced Institute of Science and Technology and Courant Institute-NYU, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, Korea Advanced Institute of Science and Technology / NewYork University, Sandia National Labs, Plasma, Pulsed-Power, and Microwave Lab, Nuclear Engineering and Radiological Sciences Dept., University of Michigan, Varian Semiconductor Equipment Associates, Gloucester, MA, Dominion University, Norfolk, VA, Sheffield Hallam University, GE Global Research, Kintech, University of Nebraska, University of Fribourg, Switzerland, CAMS, Flinders University, Australia, University of Nantes, France, CFD Research Corporation, Huntsville, AL, USA, Research Professor

  • Paule Maguire

    Department of Chemistry and Physics, Lamar University, Applied Materials, Sandia National Laboratories, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, D-44780 Bochum, Germany, Ecole Polytechnique, France, Assistant Research Professor, University of Saskatchewan, PPPL, University of Saskatchewan, Saskatoon, Canada, Plasma Physics Laboratory, Princeton University, Technische Universiteit Eindhoven, Institut fur Niedertemperatur Plasmaphysik, Old Dominion University, Norfolk, VA 23529, Korea Advanced Institute of Science and Technology \& New York University, Korea Advanced Institute of Science and Technology, St.Petersburg State Politechnical University, St.Petersburg, Russia, Hanyang University, University of Nantes, Eindhoven University of Technology, Universidad Nacional Autonoma de Mexico, Air Force Research Laboratory, Innovative Scientific Solutions, Inc, University of Cambridge, UK, University of Bristol, UK, University Kiel, Germany, INP Greifswald, Germany, KRISS, INP, Greifswald, Germany, Australian National University, Drake University, University of Central Florida, University of Missouri-Rolla, John Carroll University, Indiana University-Purdue University Fort Wayne, University of Southampton, UK and Hong Kong Polytechnic University, University of Nottingham, UK, University of Pittsburgh, Department of Physics, Pittsburgh, PA 15260, Department of Computer Science, Lamar University, Institute of Nuclear Physics, Moscow State University, Russia, Univ. of Houston, Dublin City University, Ireland, West Virginia University, Nagoya Institute of Technology, National University of Ireland, Maynooth, 3M Company, Samsung Electronics, Kyoto University, EM2C, Ecole Centrale, CNRS, Chatenay, France, University of Duisburg-Essen, Ruhr Uni Bochum, LSP, UJF, CNRS, Grenoble, France, Lawrence Berkeley National Laboratory, Tech-X Corporation, Dublin City University, Princeton Plasma Physics Laboratory, Plasma Physics Division, Naval Research Laboratory, The Open University, United Kingdom, Eindhoven University of Technology, The Netherlands, University of Minnesota, Universit\'e Joseph Fourier de Grenoble, France, Nagoya University, Japan, West Virginia University, Physics Department, Morgantown, WV 26506-6315, Dept. of Physics and Astronomy, The Open University, Milton Keynes, UK, Institute for Plasma and Atomic Physics, CPST, Ruhr-University Bochum, Germany, CAMS, Australian National University, Schuster Laboratory, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK, Centre for Antimatter-Matter Studies, Griffith University, ISAS/JAXA, University of Tokyo, Department of Aeronautics and Astronautics, Kyoto University, Kyoto, Japan, University of Texas at Austin, LTM, Grenoble, LSP, Grenoble, CPAT,Toulouse, LPGP, Orsay, France, NRL-NRC Postdoctoral Associate, SFA, Crofton, MD, Center for Plasma Science and Technology CPST, Ruhr University Bochum, D-44780 Bochum, Germany, Department of Physics, University Duisburg-Essen, D-45141 Essen, Germany, LACE, UCBL, CNRS, Lyon, France, LPTP, Ecole Polytechnique, CNRS, Palaiseau, France, Air Force Research Laboratory, Wright-Patterson AFB, OH, UES, INC., Dayton, OH, St. Petersburg State University, St. Petersburg, Russia, Suzuka National College of Technology, Japan, Plasma Research Laboratory, NCPST, Dublin City University, Dublin 9, Ireland, University Greifswald, Germany, Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Nagoya University, University of Liverpool, United Kingdom, LPTP, Ecole Polytechnique, Palaiseau, France, Laboratory for Optical Physics and Engineering, Dept. of Elec. and Computer Engr., University of Illinois, Laboratory for Optical Physics and Engineering, Dept. of Elect. and Computer Engr., University of Illinois, The Ohio State University (OH), Department of Physics, University of Rajshahi, Rajshahi, Bangladesh, CAMS, Murdoch University, Australia, Drake University, USA, Gothenburg University, University of Wisconsin- Madison, University of Wisconsin-Madison, Physics Dept., Sophia University, Chiyoda-ku, Tokyo 102-855, Japan, ARC Centre for Antimatter-Matter Studies, SoCPES, Flinders University, GPO Box 2100, Adelaide, 5001 Australia, Korea Advanced Institute of Science and Technology / New York University, National Fusion Research Center / Korea Advanced Institute of Science and Technology, Korea Advanced Institute of Science and Technology and Courant Institute-NYU, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, Korea Advanced Institute of Science and Technology / NewYork University, Sandia National Labs, Plasma, Pulsed-Power, and Microwave Lab, Nuclear Engineering and Radiological Sciences Dept., University of Michigan, Varian Semiconductor Equipment Associates, Gloucester, MA, Dominion University, Norfolk, VA, Sheffield Hallam University, GE Global Research, Kintech, University of Nebraska, University of Fribourg, Switzerland, CAMS, Flinders University, Australia, University of Nantes, France, CFD Research Corporation, Huntsville, AL, USA, Research Professor

  • Paule Maguire

    Department of Chemistry and Physics, Lamar University, Applied Materials, Sandia National Laboratories, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, D-44780 Bochum, Germany, Ecole Polytechnique, France, Assistant Research Professor, University of Saskatchewan, PPPL, University of Saskatchewan, Saskatoon, Canada, Plasma Physics Laboratory, Princeton University, Technische Universiteit Eindhoven, Institut fur Niedertemperatur Plasmaphysik, Old Dominion University, Norfolk, VA 23529, Korea Advanced Institute of Science and Technology \& New York University, Korea Advanced Institute of Science and Technology, St.Petersburg State Politechnical University, St.Petersburg, Russia, Hanyang University, University of Nantes, Eindhoven University of Technology, Universidad Nacional Autonoma de Mexico, Air Force Research Laboratory, Innovative Scientific Solutions, Inc, University of Cambridge, UK, University of Bristol, UK, University Kiel, Germany, INP Greifswald, Germany, KRISS, INP, Greifswald, Germany, Australian National University, Drake University, University of Central Florida, University of Missouri-Rolla, John Carroll University, Indiana University-Purdue University Fort Wayne, University of Southampton, UK and Hong Kong Polytechnic University, University of Nottingham, UK, University of Pittsburgh, Department of Physics, Pittsburgh, PA 15260, Department of Computer Science, Lamar University, Institute of Nuclear Physics, Moscow State University, Russia, Univ. of Houston, Dublin City University, Ireland, West Virginia University, Nagoya Institute of Technology, National University of Ireland, Maynooth, 3M Company, Samsung Electronics, Kyoto University, EM2C, Ecole Centrale, CNRS, Chatenay, France, University of Duisburg-Essen, Ruhr Uni Bochum, LSP, UJF, CNRS, Grenoble, France, Lawrence Berkeley National Laboratory, Tech-X Corporation, Dublin City University, Princeton Plasma Physics Laboratory, Plasma Physics Division, Naval Research Laboratory, The Open University, United Kingdom, Eindhoven University of Technology, The Netherlands, University of Minnesota, Universit\'e Joseph Fourier de Grenoble, France, Nagoya University, Japan, West Virginia University, Physics Department, Morgantown, WV 26506-6315, Dept. of Physics and Astronomy, The Open University, Milton Keynes, UK, Institute for Plasma and Atomic Physics, CPST, Ruhr-University Bochum, Germany, CAMS, Australian National University, Schuster Laboratory, School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK, Centre for Antimatter-Matter Studies, Griffith University, ISAS/JAXA, University of Tokyo, Department of Aeronautics and Astronautics, Kyoto University, Kyoto, Japan, University of Texas at Austin, LTM, Grenoble, LSP, Grenoble, CPAT,Toulouse, LPGP, Orsay, France, NRL-NRC Postdoctoral Associate, SFA, Crofton, MD, Center for Plasma Science and Technology CPST, Ruhr University Bochum, D-44780 Bochum, Germany, Department of Physics, University Duisburg-Essen, D-45141 Essen, Germany, LACE, UCBL, CNRS, Lyon, France, LPTP, Ecole Polytechnique, CNRS, Palaiseau, France, Air Force Research Laboratory, Wright-Patterson AFB, OH, UES, INC., Dayton, OH, St. Petersburg State University, St. Petersburg, Russia, Suzuka National College of Technology, Japan, Plasma Research Laboratory, NCPST, Dublin City University, Dublin 9, Ireland, University Greifswald, Germany, Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Nagoya University, University of Liverpool, United Kingdom, LPTP, Ecole Polytechnique, Palaiseau, France, Laboratory for Optical Physics and Engineering, Dept. of Elec. and Computer Engr., University of Illinois, Laboratory for Optical Physics and Engineering, Dept. of Elect. and Computer Engr., University of Illinois, The Ohio State University (OH), Department of Physics, University of Rajshahi, Rajshahi, Bangladesh, CAMS, Murdoch University, Australia, Drake University, USA, Gothenburg University, University of Wisconsin- Madison, University of Wisconsin-Madison, Physics Dept., Sophia University, Chiyoda-ku, Tokyo 102-855, Japan, ARC Centre for Antimatter-Matter Studies, SoCPES, Flinders University, GPO Box 2100, Adelaide, 5001 Australia, Korea Advanced Institute of Science and Technology / New York University, National Fusion Research Center / Korea Advanced Institute of Science and Technology, Korea Advanced Institute of Science and Technology and Courant Institute-NYU, Institute for Theoretical Electrical Engineering, Ruhr University Bochum, Korea Advanced Institute of Science and Technology / NewYork University, Sandia National Labs, Plasma, Pulsed-Power, and Microwave Lab, Nuclear Engineering and Radiological Sciences Dept., University of Michigan, Varian Semiconductor Equipment Associates, Gloucester, MA, Dominion University, Norfolk, VA, Sheffield Hallam University, GE Global Research, Kintech, University of Nebraska, University of Fribourg, Switzerland, CAMS, Flinders University, Australia, University of Nantes, France, CFD Research Corporation, Huntsville, AL, USA, Research Professor