Published online by Cambridge University Press: 01 February 2011
Good practical adhesion of sputter-deposited Cu is achieved to poly(tetrafluoroethylene-co-perfluoropropyl vinyl ether) (PFA) surfaces at short treatment times of vacuum UV (VUV) photo-oxidation downstream from Ar microwave (MW) plasma. Factors contributing to the adhesion include: (1) an improvement in wettability as observed by water contact angle measurements; (2) surface roughening; (3) defluorination of the surface; (4) cross-linking at the surface and (5) incorporation of oxygen as CF-O-CF2, CF2-O-CF2 and CF-O-CnF2n+1 moieties. With long treatment times, a cohesive failure occurred within the modified PFA and not at the Cu-PFA interface due to extensive chain scission weakening its mechanical properties.