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Title: Negative ion behavior in single- and dual-frequency plasma etching reactors: Particle-in-cell/Monte Carlo collision study

Abstract

Particle-in-cell/Monte Carlo simulations are used to simulate the trajectories and energies of randomly sampled F{sup -} and CF{sub 3}{sup -} ions in capacitively coupled radio-frequency discharges, in order to clarify the movement of the negative ions in the sheaths and plasma in both single- and dual-frequency regimes, as well as in symmetric and asymmetric discharges. In the single-frequency reactor both types of negative ions are confined in the plasma and the main loss mechanism is recombination with positive ions. In the dual-frequency reactor under certain operating conditions when the sheaths are wide and the bulk plasma is narrow the light F{sup -} ions move across from one sheath to the other, and they can even be lost at the electrodes. The main loss mechanisms are then electron detachment and absorption at the electrodes. The much heavier CF{sub 3}{sup -} ions are still confined in the bulk and represent the major negative charge. In an asymmetric discharge the electric field in the sheath to the smaller (powered) electrode is much stronger than that in the sheath to the grounded electrode. Consequently, the F{sup -} ions reach mainly the grounded electrode.

Authors:
;  [1]
  1. PLASMANT Research Group, Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk-Antwerp (Belgium)
Publication Date:
OSTI Identifier:
20778875
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 73; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevE.73.036402; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABSORPTION; ANIONS; ASYMMETRY; CARBON FLUORIDES; CATIONS; COMPUTERIZED SIMULATION; ELECTRIC FIELDS; ELECTRODES; ELECTRON DETACHMENT; ETCHING; FLUORINE IONS; HIGH-FREQUENCY DISCHARGES; ION COLLISIONS; MOLECULAR IONS; MONTE CARLO METHOD; PLASMA; PLASMA SHEATH; PLASMA SIMULATION; RADIOWAVE RADIATION; RECOMBINATION

Citation Formats

Georgieva, V., and Bogaerts, A. Negative ion behavior in single- and dual-frequency plasma etching reactors: Particle-in-cell/Monte Carlo collision study. United States: N. p., 2006. Web. doi:10.1103/PHYSREVE.73.0.
Georgieva, V., & Bogaerts, A. Negative ion behavior in single- and dual-frequency plasma etching reactors: Particle-in-cell/Monte Carlo collision study. United States. doi:10.1103/PHYSREVE.73.0.
Georgieva, V., and Bogaerts, A. Wed . "Negative ion behavior in single- and dual-frequency plasma etching reactors: Particle-in-cell/Monte Carlo collision study". United States. doi:10.1103/PHYSREVE.73.0.
@article{osti_20778875,
title = {Negative ion behavior in single- and dual-frequency plasma etching reactors: Particle-in-cell/Monte Carlo collision study},
author = {Georgieva, V. and Bogaerts, A.},
abstractNote = {Particle-in-cell/Monte Carlo simulations are used to simulate the trajectories and energies of randomly sampled F{sup -} and CF{sub 3}{sup -} ions in capacitively coupled radio-frequency discharges, in order to clarify the movement of the negative ions in the sheaths and plasma in both single- and dual-frequency regimes, as well as in symmetric and asymmetric discharges. In the single-frequency reactor both types of negative ions are confined in the plasma and the main loss mechanism is recombination with positive ions. In the dual-frequency reactor under certain operating conditions when the sheaths are wide and the bulk plasma is narrow the light F{sup -} ions move across from one sheath to the other, and they can even be lost at the electrodes. The main loss mechanisms are then electron detachment and absorption at the electrodes. The much heavier CF{sub 3}{sup -} ions are still confined in the bulk and represent the major negative charge. In an asymmetric discharge the electric field in the sheath to the smaller (powered) electrode is much stronger than that in the sheath to the grounded electrode. Consequently, the F{sup -} ions reach mainly the grounded electrode.},
doi = {10.1103/PHYSREVE.73.0},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 3,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}
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