Abstract
The effect of the O2/Ar component ratio in the CHF3 + O2 + Ar mixture on the electrical parameters of the plasma, kinetics of active particles, and their stationary concentrations under the high-frequency (13.56 MHz) induction discharge is investigated. Using jointly the plasma diagnostics and simulation techniques, (i) features of the plasma composition in the oxygen-free system CHF3 + Ar are found, (ii) the effect of oxygen on the stationary concentrations of active particles is established via the kinetics of processes under the electron impact and the reaction of the atom–molecule interaction, and (iii) a simulation analysis of the kinetics of heterogeneous processes (etching, polymerization, and destruction of a polymer film), which determine the etching mode and output characteristics, is carried out.
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This study was supported by the Russian Foundation for Basic Research, project no. 19-07-00804А.
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Efremov, A.M., Murin, D.B. & Kwon, KH. Plasma Parameters and Kinetics of Active Particles in the Mixture CHF3 + O2 + Ar. Russ Microelectron 49, 233–243 (2020). https://doi.org/10.1134/S1063739720030038
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DOI: https://doi.org/10.1134/S1063739720030038