Enhanced adhesion between a vapor deposited metal and an organic polymer

Abstract

Enhanced adhesion between a vapor deposited metal and an organic polymer surface is achieved without utilizing any intermediate surface preparatory steps. The morphology of the polymer surface is tailored to produce mounds and dimples on the surface which leads to a mechanically tougher, interdigitated metal/polymer interface. In the preferred embodiment, a solution of a solvent or solvent system and two or more polymer precursors or polymers or combinations thereof are cast in a film on a substrate and heated to spontaneously form a rough surface due to phase separation. The surface topography of such a film consists of characteristic mounds and dimples depending upon the composition of the solution. Direct metal vapor deposition onto the roughened surface results in an enhanced adhesion of the metal to the organic polymer surface. The organic polymer surface or substrate may be, but need not be, attached to yet another underlying substrate such as a ceramic (e.g., a silicon semiconductor chip), plastic or metal.