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Title: Abnormal Heating of Low-Energy Electrons in Low-Pressure Capacitively Coupled Discharges

Abstract

In low-pressure capacitively coupled plasmas, high-energy electrons are collisionlessly heated by large rf fields in the sheaths while low-energy electrons are confined in the bulk plasma by the ambipolar potential. Low-energy electrons are typically inefficiently heated due to their low collisionality and the weak rf electric field present in the bulk. It is shown, however, that as a result of the nonlinear interaction between the electron motion and the weak rf field present in the bulk, low-energy electrons can be efficiently heated. Electrons in the bulk that bounce inside the electrostatic potential well with a frequency equal to the rf excitation frequency are efficiently heated by the coherent interaction with the rf field. This resonant collisionless heating can be very efficient and manifest itself as a plateau in the electron energy probability function.

Authors:
; ; ;  [1]
  1. Department of Electronics and Electrical Engineering, Pohang University of Science and Technology, Pohang, 790-784 (Korea, Republic of)
Publication Date:
OSTI Identifier:
20957685
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevLett.98.085003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ELECTRIC FIELDS; ELECTRONS; EXCITATION; HEATING; INTERACTIONS; NONLINEAR PROBLEMS; PLASMA; POTENTIALS; PROBABILITY

Citation Formats

Park, G. Y., You, S. J., Iza, F., and Lee, J. K.. Abnormal Heating of Low-Energy Electrons in Low-Pressure Capacitively Coupled Discharges. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.085003.
Park, G. Y., You, S. J., Iza, F., & Lee, J. K.. Abnormal Heating of Low-Energy Electrons in Low-Pressure Capacitively Coupled Discharges. United States. doi:10.1103/PHYSREVLETT.98.085003.
Park, G. Y., You, S. J., Iza, F., and Lee, J. K.. Fri . "Abnormal Heating of Low-Energy Electrons in Low-Pressure Capacitively Coupled Discharges". United States. doi:10.1103/PHYSREVLETT.98.085003.
@article{osti_20957685,
title = {Abnormal Heating of Low-Energy Electrons in Low-Pressure Capacitively Coupled Discharges},
author = {Park, G. Y. and You, S. J. and Iza, F. and Lee, J. K.},
abstractNote = {In low-pressure capacitively coupled plasmas, high-energy electrons are collisionlessly heated by large rf fields in the sheaths while low-energy electrons are confined in the bulk plasma by the ambipolar potential. Low-energy electrons are typically inefficiently heated due to their low collisionality and the weak rf electric field present in the bulk. It is shown, however, that as a result of the nonlinear interaction between the electron motion and the weak rf field present in the bulk, low-energy electrons can be efficiently heated. Electrons in the bulk that bounce inside the electrostatic potential well with a frequency equal to the rf excitation frequency are efficiently heated by the coherent interaction with the rf field. This resonant collisionless heating can be very efficient and manifest itself as a plateau in the electron energy probability function.},
doi = {10.1103/PHYSREVLETT.98.085003},
journal = {Physical Review Letters},
number = 8,
volume = 98,
place = {United States},
year = {Fri Feb 23 00:00:00 EST 2007},
month = {Fri Feb 23 00:00:00 EST 2007}
}
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