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Specific Features of the Kinetics of the Reactive-Ion Etching of Si and SiO2 in a CF4 + O2 Mixture in a Low Power Supply Mode

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Abstract

The kinetics of reactive ion etching of Si and SiO2 in the plasma of a high-frequency (13.56 MHz) inductive discharge in a CF4 + O2 mixture in the range of input power of 200–600 W (0.02–0.06 W/cm3) is studied. The key plasma-chemical processes that form stationary electrophysical parameters and composition of the gas phase are identified (a), and the flux densities of neutral and charged particles on the treated surface are determined (b) with the combined use of plasma diagnostics by Langmuir probes and 0-dimensional (global) plasma modeling. It is found that the dominant etching mechanism for both materials is an ion-stimulated chemical reaction proceeding in the kinetic mode and limited by the fluorine flux. It is shown that the decrease in the effective probability of interaction in Si/SiO2 + F systems with an increase in the input power and gas pressure may be due to heterogeneous processes with the participation of oxygen atoms.

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Funding

This study was carried out as part of a state assignment of the Federal State Institution “Federal Scientific Center Research Institute for System Research,” Russian Academy of Sciences, on topic no. 0065-2019-0006 “Fundamental and applied research in the field of subwavelength holographic lithography and physicochemical processes of etching of 3D nanometer dielectric structures for the development of critical technologies for the production of electronic components.” The study and construction of models and designs of microelectronic elements was carried out in an extended temperature range (from –60 to +300°С).

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Authors and Affiliations

  1. Ivanovo State University of Chemical and Technology, 153000, Ivanovo, Russia

    A. M. Efremov

  2. Federal State Institution “Federal Scientific Center Research Institute for System Research,” Russian Academy of Sciences, Moscow, Russia

    V. B. Betelin

  3. Korea University, 339-700, Sejong, South Korea

    K.-H. Kwon

Authors
  1. A. M. Efremov
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  2. V. B. Betelin
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  3. K.-H. Kwon
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Correspondence to A. M. Efremov.

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Efremov, A.M., Betelin, V.B. & Kwon, KH. Specific Features of the Kinetics of the Reactive-Ion Etching of Si and SiO2 in a CF4 + O2 Mixture in a Low Power Supply Mode. Russ Microelectron 50, 303–310 (2021). https://doi.org/10.1134/S1063739721040053

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  • DOI: https://doi.org/10.1134/S1063739721040053

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