INVESTIGATION OF THE SURFACE-CHEMISTRY OF TEFLON .1. EFFECT OF LOW-ENERGY ARGON ION IRRADIATION ON SURFACE-STRUCTURE

PFA (tetrafluoroethylene and perfluoroalkoxyvinyl ether copolymer) surfaces were treated with low energy (0.5-3.0 keV range) Ar+ ions. The effects of ion energy, fluence, and ion type were studied individually. Modifications of the surface composition by the Ar+ ion bombardment were studied using X-ray photoelectron spectroscopy. The ion bombardment caused surface defluorination with bond breaking particularly at ion energies greater-than-or-equal-to 2 keV, leading to an unsaturated cross-linked, partially fluorinated network. The surface modification was found to be more dramatic with increasing ion energy and ion fluence. Fast atom bombardment spectrometry reveals that modifications of the PFA surface are characterized by severe defluorination processes due to loss of CF2, CF2CF2, CF2CF3, CF2CF2CF3, and OC(x)F(y) mass fragments.