Study on generation of electro-chemical migration in layered insulating films for flexible printed circuit

摘要

Printed circuit boards for communication equipment have been promoted by mounting circuits in them with higher-density. It is said that an ECM (Electro Chemical Migration) generates in the insulating material when a high electric stress is applied to the board material under high temperature with high humid condition. Since the ECM degrades the insulation properties of it, it is necessary to use a suitable material for prevent the generation of ECM. However, while many research for the ECM in some traditional rigid circuit boards were carried out, there is a few reports about ECM in FPC (Flexible printed circuit). Which is usually used in many advanced recent electronic devices. Therefore we attempted to study the occurrence of the ECM in the FPC.