Composite SiOx/fluorocarbon plasma polymer films prepared by r.f. magnetron sputtering of SiO2 and PTFE

Composite films SiOx/fluorocarbon plasma polymers were prepared by r.f. sputtering from two balanced magnetrons equipped with polytetrafluoroethylene (PTFE) and silica (SiO2) targets. Argon was used as the working gas. The obtained films were characterised by means of XPS, RBS, FTIR, AFM, TEM, microhardness and static contact angle measurements. The obtained SiOx/fluorocarbon plasma polymer films reveal different wettability (static contact angle of water ranges from 68° to 40°) and hardness (ranges from 720 to 3200 N/mm2) when the volume fraction ratio (filling factor) of SiO2 changes from 0.01 to 0.7. The concentration of elements determined by RBS/ERDA varies strongly over this range of filling factors. The heterogeneous structure of the composite films is indicated by TEM at high SiOx contents.