Direct patterning of silver circuit using surface-modification and UV irradiation on polyimide resin

A simplified method is proposed for the formation of a silver circuit pattern on a polyimide resin substrate through modification of the resin surface followed by adsorption of silver(I) ion and UV photoreduction to form patterns. The amide bond and carboxyl group, as a cation exchange group, were formed on the polyimide resin surface by a potassium hydroxide treatment. UV irradiation of the adsorbed silver(I) ion results in the formation of a silver thin film. Silver circuit patterns are easily formed on the modified polyimide resin substrates without using a plating resist by use of a metal-on-quartz mask.