Nano- and micro-scale wear of fluorinated carbon films

Wear of fluorinated carbon films deposited by plasma assisted chemical vapor deposition has been studied by atomic force microscopy and the sliding sphere test. The films microstructure and chemical composition were also investigated. The films became polymeric upon fluorine incorporation, as revealed by density measurements, Raman and X-ray photoelectron spectroscopies. It was shown that the wear marks produced with a microscope diamond tip are strongly related to the film hardness and microstructure. The wear depth measured on a polymeric film is greater compared with the ones obtained from hard carbon and carbon fluorinated films. At nanometer scale, the minimum force necessary to scratch the films increases with the film hardness, while the wear rate decreases. Similar behaviors were observed in both nano- and micro-scale wear experiments.