Epoxy polymers are frequently used for electronic purposes, in particular for built up layers and micro-vias in advanced printed circuit boards. The adhesion of the plated metal layers to this polymer surface is of prime importance for the reliability of the interconnection. Chemical treatment of the polymer surface changes the chemical and physical nature of the polymer. This results in specific groups of the polymer chain present on the surface and changes the roughness of the polymer layer. The influence of swellers and oxidizing agents on the polymer surface roughness and the chemical properties of the surface are investigated. The surface is analyzed by atomic force microscopy, attenuated total reflectance-infrared (ATR-IR) spectroscopy, dynamic contact analyses (DCA), and peel strength measurements after electroless and electroplating of the surface. The changing of the chemical functionalities on the surface, which is detected by ATR-IR and DCA plays an important part in the adhesion strength of electrochemically plated copper. The combination of roughness and the presence of certain chemical groups, like alcohols, play an important role in the adhesion of electrochemically deposited metals to the polymer surface. (C) 2004 The Electrochemical Society.