Abstract
Electroless plating has not been applied to FPC production processes as a method of metallization on PI and PEN surfaces because of the adhesion deterioration problem after heat load. This problem could be a result of the necessary pretreatment surface modification required for electroless plating. This study focused on reducing the modification layer thickness to solve this problem. With a modification layer on a PI film of approximately 10 nm, the peeling strength dropped from 0.58 kN/m to 0.22 kN/m after heat load. However, when the modification layer was reduced to several nm, the peeling strength rose from 0.39 kN/m to 0.55 kN/m. In the case of PEN film, the rise of peeling strength was observed while the modification conditions were weak. Based on the analysis of the stripped interface, it can be concluded that the resin deteriorates due to the heat load when there is a large amount of modification. On the other hand, no deterioration is observed, which can therefore improve the adhesion interface.