Interfacial Adhesion Characteristics Between Electroless-Plated Ni and Polyimide Films Modified by Alkali Surface Pretreatment

摘要

The effects of KOH + ethylenediamine (EDA) and subsequent KMnO_(4) + KOH treatments on the interfacial adhesion characteristics of an electroless-plated Ni/polyimide system were investigated for flexible printed circuit board applications. The interfacial adhesion energy, evaluated from 180 deg peel tests during the steady-state peeling process, showed a twofold decrease after subsequent KMnO_(4) + KOH treatment of the pyromellitic dianhydianiline-oxydianiline polyimide surface. Atomic force microscopy and x-ray photoemission spectroscopy results clearly reveal that this decrease can be attributed to both mechanical interlocking and chemical bonding effects.