Plasma Polymerization Behavior of Fluorocarbon Monomers in Low‐Pressure AF and RF Discharges

Abstract

AbstractThe plasma polymerization behavior of fluorocarbon monomers was investigated using C3F6, C3F6O, C4F10 and C2F4H2, which were compared to hydrocarbons such as methane and butane. The plots of the normalized thickness growth rates of plasma polymers, GR/FM, versus the energy input composite parameters, W/FM, revealed the energy‐deficient and monomer‐deficient domains for each monomer, along with the critical energy input, (W/FM)c, representing the transition between the two domains. The luminous gas phase in fluorocarbon discharges does not contain much polymer‐forming species and thus, the monomer‐deficient domain shifted to a much lower W/FM and GR/FM values than in the case of hydrocarbon systems. For hydrocarbon systems, deposition rates were greater in RF than in AF discharges, which is opposite to the situation observed for the fluorocarbon systems. These differences were attributed to the locations of the dissociation glows and to the nature of the luminous gas phase in respect to polymer‐forming species.magnified image