Plasma polymerization and deposition of glycidyl methacrylate on Si(100) surface for adhesion improvement with polyimide

Abstract

Thin polymer films were deposited on Si(100) surfaces by plasma polymerization of glycidyl methacrylate (GMA) under different glow discharge conditions. The FT-IR, X-ray photoelectron spectroscopy (XPS), and amine treatment results suggested that the epoxide functional groups of the deposited films had been preserved to various extents, depending on the plasma deposition conditions. The use of a low radio frequency power (∼ 5 W) and a relatively high system pressure (100-400 Pa) readily resulted in the deposition of thin films having nearly the same composition of the epoxide functional groups as that of the GMA homopolymer. The plasma-polymerized GMA (PP-GMA) thin films deposited on the Ar plasma-pretreated Si(100) surfaces were retained to a large extent after acetone extraction, suggesting the presence of covalent bonding between the PP-GMA layer and the Si surface. Thermal imidization of the poly(amic acid) precursor of polyimide on the GMA plasma-polymerized Si(100) surface resulted in a strongly adhered polyimide film. The adhesion results further suggested that the GMA polymer had been grafted on the Si(100) surface and the epoxide functional groups had undergone reactive interaction (curing) with the carboxylic and amine groups of the poly(amic acid) during thermal imidization. Copyright © 2001 John Wiley and Sons, Ltd.