All-wet metallization process for transparent polyimide films

Abstract

Electrically conductive Ag thin films were successfully formed onto optically transparent polyimide films via all-wet chemical process. The process involves alkaline-induced surface modification of polyimide films, subsequent incorporation of Ag+ ions through ion exchange reaction followed by reduction of incorporated Ag+ ions. Initial alkaline treatment time determines thickness (depth) of surface-modified layer and amount of Ag + ions loading consequently. Higher Ag+ ions loading result in forming electrically conductive Ag thin films and its granular interfacial structure. Cu electroplating is able to be conducted on the resulting Ag thin films directly, and adhesive strength between the Cu(/Ag) film and transparent polyimide substrate reached up to 2 kN m-1.