EFFECT OF PLASMA POLYMER DEPOSITION METHODS ON COPPER CORROSION PROTECTION

The behavior of plasma polymer coating for Cu corrosion protection was investigated in de cathodic polymerization, with and without anode ma gnetron enhancement, af magnetron glow discharge polymerization, and r f glow discharge polymerization. The combination of visual and scannin g electron microscopy observations established general trends in an ac celerated wet/dry cycle corrosion testing environment containing 0.1N chloride ions. Dc anodic magnetron cathodic polymerization of TMS offe red the best Cu corrosion protection due to an enhanced deposition uni formity and adhesion of the deposited plasma polymer to the Cu substra te. No corrosion was observed after 25 wet/dry cycle accelerated corro sion tests when uncoated Cu suffered a severely generalized attack in one cycle. Superior corrosion protection was also performed by an af p lasma polymerized coating of C4F10 + H-2 (1 : 1) at a low-energy input density and of methane at high-energy input and high deposition thick ness carried out in the range of this study. The application of plasma polymers which showed high water vapor permeation resistance and surf ace dynamic stability greatly reduced the pitting densities. (C) 1996 John Wiley & Sons, Inc.