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Parameters and Composition of Plasma in a CF4 + H2 + Ar Mixture: Effect of CF4/H2 Ratio

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Abstract

The electrophysical parameters of the plasma and the kinetics of plasma-chemical processes in a CF4 + H2 + Ar mixture while varying the CF4/H2 ratio are studied. When using diagnostic methods and plasma modeling together, it is found that replacing tetrafluoromethane with hydrogen (a) leads to a decrease in the plasma density and an increase in electronegativity; and (b) it causes a disproportionately sharp drop in the concentration of fluorine atoms. The reason for the latter effect is the increase in the frequency of the death of atoms in reactions of the CHFx + F → CFx + HF type initiated by heterogeneous recombination via the CFx + H → CHFx mechanism. The simultaneous increase in the concentration of polymer-forming CHxFy (x + y < 3) radicals indicates an increase in the polymerization load of the plasma on the surfaces in contact with it.

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Funding

This study was supported by the Russian Science Foundation grant no. 23-29-00771, https://rscf.ru/project/23-29-00771/.

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Authors and Affiliations

  1. Valiev Institute of Physics and Technology, Russian Academy of Sciences, 117218, Moscow, Russia

    A. V. Miakonkikh, V. O. Kuzmenko & K. V. Rudenko

  2. Ivanovo State Chemical-Technological University, 153000, Ivanovo, Russia

    A. M. Efremov

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  1. A. V. Miakonkikh
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  2. V. O. Kuzmenko
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  3. A. M. Efremov
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Miakonkikh, A.V., Kuzmenko, V.O., Efremov, A.M. et al. Parameters and Composition of Plasma in a CF4 + H2 + Ar Mixture: Effect of CF4/H2 Ratio. Russ Microelectron 53, 70–78 (2024). https://doi.org/10.1134/S1063739723600012

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