Epoxy Polymer Surface Roughness Modeling Based on Kinetic Studies of Wet Chemical Treatments

Abstract

Epoxy polymers are frequently used for constructing buildup layers. Atop the dielectric polymer metal layers are plated by means of a wet-chemical electroless and/or electroplating process. The adhesion of the plated metal layers to this polymer surface is of prime importance for reliability of the interconnection. An increase in the roughness of the polymer surface plays an important part in the adhesion strength of plated metal layers by increasing the total area of interface between both layers. Hence, the evolution of polymer surface roughness with time due to the chemical treatment is of prime importance for determining the reliability of interconnections. A kinetic study of wet solution swellers and oxidizers is made, based on atomic force microscopy roughness measurements. Each chemical or combination of chemical treatments in a certain sequence has its influence on the evolution of roughness. The evolution of surface roughness also indicates the mechanisms that lead to the formation of roughness on the surface. Different models are proposed to explain the influence of sweller agents on polymer surface roughness. The kinetics of roughness formation under influence of swellers is modeled and the bases of the influence of swellers on oxidizing treatments are examined. © 2004 The Electrochemical Society. All rights reserved.