Recent Advances in the Atmospheric Pressure PE-CVD of Fluorocarbon Films: Influence of Air and Water Vapour Impurities

The influence of air and water vapour on the deposition process of fluoropolymers in argon-hexafluoropropene (Ar-C3F6) filamentary dielectric barrier discharges was investigated by adding known concentrations of these contaminants to the feed gas. The obtained results show that Ar-C3F6 DBDs allow in depositing thin films with a XPS F/C ratio as high as 1.7. Under the experimental conditions investigated, contaminant addition slightly affects the F/C ratio of the coatings, and does not cause appreciable O- and N-uptake, but induces a decrease of the deposition rate. Preliminary results from the DES investigation of the gas phase and the GC-MS analysis of the gas effluent are also reported.