Surface modification with special morphology for the metallization of polyimide film

Metallized polyimide (PI) film has great applications in the field of flexible electronics. Surface property adjustment is considered as an effective way to realize the metallization of PI film by chemical methods . In this work, we demonstrate a facile approach to fabricate metallized PI film via surface modification and electroless plating . Polyethyleneimine (PEI) cross-linked with glutaraldehyde (GA) is used as a modifier to act on the surface of alkali-treated PI film, and a special regular morphology is obtained. This PEI-modified PI film possesses not only functional groups for chemical bonding but also large surface roughness for mechanical locking with metallic copper layer. The resulting copper layer has low resistivity (2.30 μΩ·cm) and satisfactory adhesion to PI film (the highest score of 5B according to ASTM D3359), and the metallized PI sample exhibits reliable flexibility. These results demonstrate a promising potential of this approach in the field of PI film metallization with impact in wearables, light-weight, and flexible electronics.