Abstract
A novel Cu surface treatment method was developed to improve the adhesion between smooth Cu surfaces and epoxy dielectric layers using a silane coupling agent. In this process, the Cu surface was first modified with a functional group, which was then treated with the silane coupling agent. Here, we investigated the effect of the functional group and the silane coupling agent on the adhesion strength between Cu and epoxy dielectric layers. We also investigated the influence of the Cu/dielectric adhesion layer on smooth Cu wirings of the printed circuit board manufacturing process compatibility. From this study, it was found that two-step Cu surface modification with triazine trithiol followed by treatment of mercapto-group containing silane coupling agent would dramatically enhance the adhesion strength. It was found that a thin triazine trithiol layer was very effective to improve desmear-resistance.
