Gas Phase Composition and Fluorine Atom Kinetics in SF6 Plasma

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Abstract

The model-based study of SF6 plasma composition in respect to both neutral and charged components in a wide range of electron density was carried out. The key plasma chemical processes determining steady-state densities if fluorine atoms under conditions of low- and high-density plasmas were figured out. It was shown that optimized (reduced by the exclusion of non-effective reactions) kinetic schemes provide the satisfactory agreement between modeling results and experimental data from literature sources.

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About the authors

A. V. Myakonkikh

Valiev Institute of Physics and Technology RAS

Author for correspondence.
Email: miakonkikh@ftian.ru
Russian Federation, Moscow

V. O. Kuzmenko

Valiev Institute of Physics and Technology RAS

Email: miakonkikh@ftian.ru
Russian Federation, Moscow

A. M. Efremov

Valiev Institute of Physics and Technology RAS; Molecular Electronics Research Institute (MERI)

Email: miakonkikh@ftian.ru
Russian Federation, Moscow; Zelenograd

K. V. Rudenko

Valiev Institute of Physics and Technology RAS

Email: miakonkikh@ftian.ru
Russian Federation, Moscow

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2. Fig. 1. Rate constants of reactions under the action of electron impact involving SF6 molecules leading to the formation of neutral (a) and charged (b) products. In Fig. b): solid lines - ionization, dashed lines - sticking. The numerical labels on the solid curves correspond to the reaction number in Tables 1 and 2.

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3. Fig. 2. Concentrations of neutral particles (a) and kinetics of fluorine atom formation (b) at = 3 eV. The numerical labels on the solid curves in Fig. b) correspond to the reaction number in Tables 1 and 2, with the number in parentheses reflecting the value of the parameter “x” in the SFx formula. The dotted line shows the total rate of atom formation.

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4. Fig. 3. Comparison of calculated (dashed line) and experimental (solid line + symbols) concentrations of fluorine atoms from [15] (a) and [16] (b). Both experimental curves in Fig. a) correspond to the same conditions of plasma excitation, but were obtained at different values of the actinometric coefficient.

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5. Fig. 4. Concentrations of positive (a) and negative (b) ions at = 3 eV. The dotted line shows the total concentration.

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