Effect of C2H4/N2 Ratio in an Atmospheric Pressure Dielectric Barrier Discharge on the Plasma Deposition of Hydrogenated Amorphous Carbon-Nitride Films (a-C:N:H)

Abstract

The goal of this study was to investigate the properties and growth mechanisms of nitrogen-containing carbon-based coatings obtained with an atmospheric pressure dielectric barrier discharge in an N 2 -C 2 H 4 atmosphere. Radically different chemical compositions were observed depending on C 2 H 4 /N 2 ratio. With a low C 2 H 4 concentration (\400 ppm) as a function of the residence time in the discharge, two different growth mechanisms were observed consisting of a highly nitrogenated coating (N/C [ 0.8) and low hydrogen content. At the short residence time, growth was due to mobile small radicals that procured a smooth yet soluble coating, while at the longer residence time, diffusionlimited aggregation of high sticking N-containing radicals produced a cauliflower-like structure. With a high C 2 H 4 concentration (C2,000 ppm), a polymer-like coating with relatively lower nitrogen content (N/C * 0.2) was observed with a cauliflower morphology for the entire coating. Nanoindentation measurements revealed very different physical properties in the two types of coatings.

Plasma chemical reactions in C2H2/N2, C2H4/N2, and C2H6/N2 gas mixtures of a laboratory dielectric barrier discharge

“…Comparison of C 2 H 2 /N 2 and C 2 H 4 /N 2 (left) and of C 2 H 4 /N 2 and C 2 H 6 /N 2 mass spectra with plasma in the mass range M/Z up to 180. Similar ratios had been observed for films deposited in a C 2 H 4 /N 2 dielectric barrier discharge plasma (Sarra-Bournet et al, 2010).…”

Anti-Fog Layer Deposition onto Polymer Materials: A Multi-Step Approach

“…These experiments showed that the amount of surface amino groups was 2.5%, corresponding approximately to 0.5-2 amine/nm 2 [42], and was thus adequate for surface conjugation. Another interesting finding is that these data were recorded 1 week after the organic layer deposition, thus confirming that the remaining amine concentration was stable and no longer susceptible to aging effects [43,44].…”

Ultra-Shallow Chemical Characterization of Organic Thin Films Deposited by Plasma and Vacuum-Ultraviolet, Using Angle- and Excitation Energy-Resolved XPS

“…4) generally involves four components (or sub-peaks), here labelled cc, c1, c2 and c3. Several different attributions can be found in the literature, but none appear to be completely satisfactory, on [42]. These assignments, which are mainly deduced from comparisons with chemical shifts in standard polymers [32], cannot be considered reliable for quantitative analyses.…”