Fluorine doped titanium dioxide films manufactured with the help of plasma enhanced chemical vapor deposition technique

In this work, a manufacture of TiO2 coatings doped with fluorine, in a concentration range of 0.6 to 6.7 at.%, is presented. The coatings were deposited onto silicon and quartz substrates with the help of radio frequency plasma enhanced chemical vapor deposition technique. They were characterized with regard to their elemental composition, chemical structure, phase composition, surface topography, optical properties, photo-wettability and bactericidal properties. For that purpose, such analytical techniques as X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy, atomic force microscopy, ultraviolet-visible absorption spectroscopy and variable angle spectroscopic ellipsometry were used. GIXRD analysis of the coatings doped with fluorine shows their amorphous structure. Apart from TiO2 bonding, FTIR and XPS analyses of the films reveal a presence of TieF and OeF bonds. Surface morphology studies indicate an increasing number of surface defects along with growing fluorine content. The coatings exhibit promising optical properties with some of them showing a super-hydrophilic effect as well. On the other hand, the bactericidal effect of fluorine doped TiO2 coatings is weaker than that of plain TiO2.