Concerning the Effect of Type of Fluorocarbon Gas on the Output Characteristics of the Reactive-Ion Etching Process

• Published in: Russian microelectronics Vol. 49; no. 3; pp. 157 - 165
• Main Authors: Efremov, A. M., Murin, D. B., Kwon, K.-H.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.05.2020; Springer Nature B.V
• Subjects: Anisotropy; Binary systems; Chemical reactions; Composition effects; Electrical Engineering; Electron bombardment; Engineering; Fluorine; Ion bombardment; Perfluorocarbons; Physical properties; Plasma etching; Process parameters; Reaction kinetics; Reactive ion etching; Selectivity; Silicon dioxide; Steady state
• ISSN: 1063-7397; 1608-3415
• DOI: 10.1134/S1063739720020031

The comparative research of the parameters, steady-state composition, and the effects of heterogeneous interaction in the plasma of fluorocarbon gases C x H y F z with various z / x relations in conditions of an induction RF (13.56 MHz) discharge is carried out. The binary systems C x H y F z + Ar based on CF 4 ( z / x = 4), CHF 3 ( z / x = 3), and C 4 F 8 ( z / x = 2) are used as the subjects of research. Through the methods of diagnostics and simulation of plasma we found (a) the reasons of the differences in the physical parameters (temperature and density of electrons, energy of ion bombardment) of the plasma in the studied systems; (b) the special characteristics of the kinetics of the plasma-chemical processes determining the steady state concentrations of fluorine atoms and polymer-forming radicals; and (c) the special characteristics of the kinetics of the heterogeneous process forming the output parameters (rate, selectivity, anisotropy) of the reactive ion etching of Si and SiO 2 .