The adhesion of plated metal layers to epoxy polymer surfaces is of prime importance for the reliability of electronic interconnections. An increase in the roughness of the polymer surface, caused by chemical treatment, strengthens adhesion by increasing the total area of interaction between both layers. The evolution of the roughness at the polymer surface is studied through the kinetics of the chemical reactions on the surface. Sweller agents, that are able to diffuse through the free volume of the polymer, react with polar groups present in the bulk of the polymer and form channels. An increase in polar groups at the surface and the formation of channels facilitates the transport of water through the free volume of the polymer. The polar groups in these patches react with oxidizers and cause the formation of cavities as reported in literature. A mathematical model is developed to explain the influence of swellers and oxidizing agents on the development of polymer surface roughness. This model is based on atomic force microscopy measurements for the roughness and on attenuated total reflectance-infrared and electron spectroscopy for chemical analysis for the chemical changes on the polymer surface. Mass measurements are also used to record mass changes. The proposed model permits the prediction of roughness evolution. (C) 2004 The Electrochemical Society.