Plasma-chemical polymerization in CH4-based mixtures containing various amounts of rare gases

For constant-current glow discharge in Ar + Ne + CH4 mixtures in a pressure range of 13–250 Pa and a discharge current range of 5–100 mA, the following characteristics were determined: gas temperature; longitudinal electric field intensity; radiation line intensities of Ne (3p → 3s) and Ar (4p → 4s) transitions; intensities of Hα, Hβ, and Hγ lines of Balmer series; concentrations of Ne, Ar, and H atoms in metastable and resonance states; concentration of atomic hydrogen; and growth rate of polymer films. The composition of the polymer films was analyzed with the use of infrared spectroscopy. Mathematical modeling of discharges under the selected conditions was carried out. The results of calculations were compared to the experimental data. The mechanism of processes that proceed in the glow discharge plasma is shown to depend strongly on the Ne-to-Ar concentration ratio, which results in the qualitative difference between the compositions of films that were grown at the same pressure and discharge current, as well as in the difference between the growth rates of the films.