Fast selective metal deposition on polymers by using IR and excimer VUV photons

The major advantages of infra-red (IR) lamp induced decomposition of metal organic films for large-area deposition of metal films on substrate surfaces, local excimer laser ablation of thin metal films, and subsequent electroless metal plating were combined to develop a novel fast selective metallisation technique for thermally stable polymers. With the new method, metal structures with high edge quality on different types of polyimide (PI) foils can be produced easily. Without damaging the underlying PI substrate, the metal organic film (e.g. palladium acetate, PdAc) can be decomposed by infra-red irradiation in only about one second. The precise etching capability of ArF excimer laser ablation at λ=193nm allows the IR-induced palladium (Pd) layers to be removed from the PI surface with one excimer laser pulse, selectively. The residual patterned Pd film on the PI surface then acts as an excellent catalyst for conventional electroless copper plating.