Mechanism for Improving the Heat-Resistance of Adhesive Interface in Flexible Printed Circuits

Abstract:
Flexible printed circuits (FPC’s) have been utilized for various kinds of applications in electronics. Recently, due to the increasing demand for FPC's as power electronics components, they are required to withstand high temperatures. In this study we will explain the degradation mechanism of the adhesive interface between the conductive metal layer and the insulative polyimide base film at high temperatures. By chemiluminescence measurements, it has been proven that the copper layer which is attached directly to the fluoropolymer (FKM) adhesive layer causes the oxidation reaction of the adhesives when heated at high temperatures.