Abstract
In this paper, we investigate the kinetics and mechanisms of reactive-ion etching of Si and SiO2 in the plasma of an HBr + O2 mixture with a variable initial composition under conditions of the high-frequency (13.56 MHz) inductive discharge. In the experimental and theoretical (model) analysis of the plasma parameters, the key plasma-chemical processes that form the stationary composition of the gas phase are identified and the densities of active particle fluxes onto the surface under processing are determined. It is found that the increase in the O2 concentration in the plasma-forming mixture is accompanied by a decrease in the kinetic coefficients (probability of effective interaction and etching yield) that characterize the heterogeneous stages of the etching process. It is assumed that the main mechanism of this effect is the oxidation of SiBrx etching products to low volatile compounds of the SiBrxOy type.
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Funding
This work was carried out as part of a state task for the Scientific Research Institute of System Analysis, Russian Academy of Sciences (fundamental scientific research) on topic no. 0065-2019-0006 “Fundamental and Applied Research in the Field of Subwavelength Holographic Lithography, Physicochemical Processes of Etching 3D Nanometer Dielectric Structures for the Development of Crucial Electronic Component Manufacturing Technologies.”
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Translated by Yu. Kornienko
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Efremov, A.M., Betelin, V.B. & Kwon, KH. Kinetics and Mechanisms of Reactive-Ion Etching of Si and SiO2 in a Plasma of a Mixture of HBr + O2 . Russ Microelectron 49, 379–384 (2020). https://doi.org/10.1134/S1063739720060037
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DOI: https://doi.org/10.1134/S1063739720060037