Transparent Water-repellent Films Containing Fluoro-alkyl Functions by RF Plasma-enhanced CVD

Summary

Transparent water-repellent films containing fluoro-alkyl functions were prepared on polycarbonate, glass and Si substrates by rf plasma-enhanced CVD. The vapours of the fluoro-alkyl silanes were used as raw materials. The substrate temperature during deposition was around 50°C. The films obtained had good water repellency. The maximum contact angle for a water drop was 107 degrees. The contact angles obtained depended on the number of—(CF₂)—in FAS molecules. FTIR and XPS were used to investigate the film properties. The existence of the fluoro-alkyl functions CP₃—,—CF₂—and >CF—was confirmed at the film surfaces. The transmittance of the PC substrate was improved by the coating. These films also have a function as anti-reflective coatings.