Abstract
In this paper, we investigate the relationship between the external and internal plasma parameters in a C4F8 + O2 + Ar mixture under conditions of an inductive radio-frequency (13.56 MHz) discharge. With the combined use of plasma diagnostics based on Langmuir probes and zero-dimensional (global) plasma simulation, first, the key plasma-chemical processes that form stationary electrophysical parameters and gas phase composition are identified; second, the densities of the neutral and charged particle fluxes to the surface contacting with the plasma are determined; and third, a phenomenological (using tracking parameters as ratios of particle flux densities) analysis of the kinetics of the heterogeneous processes that occur during SiO2 etching is carried out. In addition, assumptions about the mechanisms of influence of the initial mixture composition and gas pressure on the etching rate and effective interaction probability in the SiO2 + F system are made.
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This work was supported by the Russian Foundation for Basic Research, project no. 19-07-00804А.
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Translated by Yu. Kornienko
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Efremov, A.M., Murin, D.B., Sobolev, A.M. et al. Kinetics of the Volumetric and Heterogeneous Processes in the Plasma of a C4F8 + O2 + Ar Mixture. Russ Microelectron 50, 24–32 (2021). https://doi.org/10.1134/S1063739721010054
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DOI: https://doi.org/10.1134/S1063739721010054