NITROGEN DOPED DIAMOND LIKE CARBON THIN FILMS ON PTFE FOR ENHANCED HEMOCOMPATIBILITY

Diamond like carbon (DLC) doped with nitrogen thin films were synthesized on silicon and Polytetrafluroethylene (PTFE) substrates using methane, argon and nitrogen mixture ion beams in a dual ion beam deposition (DIBD) system and hot wire plasma sputtering of graphite in argon and nitrogen gas mixture. The chemical composition, electronic structure. morphology. tribological. and hemocompatible properties of the DLC films were investigated by various methods including X-ray Photoclectron Spectroscopy. Scanning Electron Microscopy, Raman Spectroscopy. scratching, nanoindentation. ball-on-disc wear tests, and platelet adhesion technique. The effects of nitrogen doping and ion beam energy on the tribological properties of DLC thin films were studied. The results show that ion deposited films are dense and smooth and that nitrogen doped DLC thin films exhibits much lower friction coefficient and enhanced hemocompatibility. Nitrogen doping improved the hardness and hemocompatibility of DLC thin films.