Modeling and experimental investigations of dielectric barrier discharges in Ar-monomer mixtures

Plasma-enhanced chemical vapor deposition (PECVD) of thin films is widely used in a variety of fields, particularly in coating and surface treatment industries. In recent years, the use of atmospheric pressure plasmas in PECVD has attracted increasing attention and extensive scientific research. Dielectric barrier discharges in argon with small amounts of siloxanes, organosilanes, or hydrocarbons, driven by sinusoidal voltages of a few kV at 19 kHz, are studied by combining modeling and experimental analysis. A time-dependent, spatially one-dimensional fluid-Poisson model, including balance equations for particle number densities and electron energy density coupled with Poisson's equation, is employed. Experimental data include ignition voltages, the chemical composition of thin films and the determination of the average deposited ion mass, obtained from profilometric and current measurements. The analysis of modeled surface fluxes of particle species reveals the central role of cations in film growth. Based on modeling results and measured average masses of deposited ions, the contributions of specific cations are identified and the reaction pathways for their formation are analyzed.