Inkjet printing using copper nanoparticles synthesized by electrolysis

A modified electrolysis method was employed to synthesize copper nanoparticles for mass production. Processing parameters including electrolyte temperature, pH and reduction agents were controlled in order to synthesize the particles continuously and directly from copper plates. As a result, well-dispersed copper nanoparticles with an average diameter of 15 nm were obtained and the oxidation of these particles was prevented by controlling the parameters. Using an amphiphilic surfactant, a water-based copper nano-colloid was prepared and printed onto a polyimide substrate using a conventional ink-jet printer. Copper patterns sintered at 230 °C showed a resistivity of 5.4 μΩ-cm (bulk resistivity; 1.67 μΩ-cm).