Fabrication of Transparent Electrode based on Metallic Nanofiber Network via Combined Heat Treatment

With the increasing interest in research on the development of next-generation technologies such as flexible smartphones, displays, and wearable devices, interest in the development of materials and processes for transparent electrodes constituting them is also increasing. The most widely used material for manufacturing transparent devices is indium tin oxide (ITO). However, ITO is scarce, expensive, and brittle, making it is essential to replace it with new materials. In this study, we successfully fabricated a transparent electrode by electrospinning polyvinylpyrrolidone (PVP) and copper electroless deposition on the polyimide film. Especially, this study suggests a new combined heat treatment that uses both the hot plate and the convection oven. Through the combined heat treatment, the junctions between the nanofibers overlapped removed consequently reducing contact resistance. The mechanical stability of the fabricated electrode was evaluated by using a highly repeated bending test. Also, through the tape-peeling test, we confirmed that the adhesive strength of the electrode was high. This method can be applied to various polymer-based, substrate which are vulnerable to annealing process.