SF6-RF-plasma environments were employed for the generation of SF x -oxygen-scavenger species, and used for the synthesis of thin highly fluorinated paper, poly(acrylic acid) (PAA), polyethylene (PE), plasma-oxidized polyethylene (OxPE), and poly(vinyl alcohol) (PVA) surface layers. The concentration of fluorine atoms in the SF6-plasma was monitored using actinometry. The relative surface atomic concentrations and the surface characteristics of the plasma-modified substrates were evaluated using electron spectroscopy for chemical analysis, contact angle goniometry, and atomic force microscopy. It was demonstrated that the plasma-produced SF x species initiate simultaneous intense surface fluorination and oxygen extraction mechanisms, and that −C−O, −CO, and −COOH functionalities are converted into −CF, −CF2, and −CF3 groups, respectively. Contact angle (CA) investigations indicate that longer plasma exposure times result in very high, stable contact angle values. It is suggested that the low stability in time of CA values for the paper samples can be related to the porous nature of the substrates and macromolecular motion. The results of these investigations open up novel ways for the plasma-enhanced synthesis of thin membrane structures with dissimilar surfaces, which might play a significant role in the area of membrane-assisted catalysis (e.g., Nafion-type structures). It is also suggested that preoxidized polymer surfaces might lead to more efficient and uniform surface fluorination processes under SF6-plasma environments in comparison to their non-oxidized counterparts. By selecting plasma-enhanced oxidation reaction mechanisms, which selectively result in the formation of −CO and −COOH groups, novel routes open up for the synthesis of CF2- and CF3-bearing surface layers.

Teflon-like thin layers were deposited on various substrate surfaces from perfluoro-1-butanesulfonyl fluoride/methane radio frequency pulsed plasma environments. The deposited films were characterized using attenuated total reflectance Fourier transform infrared spectroscopy, electron spectroscopy for chemical analysis, differential thermal analysis/thermogravimetric analysis (DTA/TG), and atomic force microscopy techniques. It has been demonstrated that the presence of methane is crucial for the deposition of fluorinated structures due to the simultaneously developed and fluorine atoms controlled competitive etching and deposition processes. It has been shown that plasma films with the highest fluorine concentrations can be generated under low duty cycle and high methane partial pressure conditions. DTA/TG data indicate that the Teflon-like layers have a fairly high thermal stability.