RF sputtering of hydrocarbon polymers and their derivatives

RF sputtering of polymeric targets was discussed from the point of view of history and present status of the field. RF sputtering of polytetrafluorethylene (PTFE) was mentioned in self-sputtering mode, argon, nitrogen and other gases. The emission of fragments from the target observed by means of quadrupole mass spectroscopy and target surface as observed by SEM were described. Columnar morphology of the sputtered films at substrate temperatures below room temperature was mentioned. Deposition rate of sputtered PTFE films was found up to one order of magnitude higher than polyimide (PI) sputtered films. Results of PI sputtering process and films characterization in terms of tribological coatings were reviewed. Polyethylene (PE) and polypropylene (PP) sputtering was found below 100 W power more than three times slower than PTFE sputtering. The films are hydrocarbon plasma polymers containing a lot of oxygen and OH groups. Above 100 W the co-evaporation from the erosion zone of the target took place and deposited films resemble much more the parent target as observed by FTIR. Finally, co-sputtering of metal and polymer that results in nanocomposite metal/plasma polymer films and sputtering of SiO2/PTFE composite target is shortly discussed.