Abstract
The purpose of this paper is to find the effect of surface finish on electrodes between the rigid printed circuit board (RPCB) and flexible PCB (FPCB) using ultrasonic vibration. The electrodes of the FPCB were electroless-plated with electroless Ni/immersion Au (ENIG) and electroless Ni/electroless Pd/immersion Au (ENEPIG) and those of RPCB were electroless-plated with ENIG. The peel strengths of the joints were investigated with various parameters, such as bonding pressure and time. This study showed that the thickness of intermetallic compound (IMC) bonded with ENEPIG surface finish was thinner than that bonded with ENIG surface finish.
