Fabrication of Large Area Sub‐200 nm Conducting Electrode Arrays by Self‐Confinement of Spincoated Metal Nanoparticle Inks

Abstract Here, the fabrication of sub‐200 nm metal wires from commercial silver inks with 50 nm particle size, 100 times narrower than with typical low‐resolution ink‐jet and screen printing in flexible electronics, is demonstrated. Using a combination of spincoating on prepatterned polymer substrates and flash lamp annealing, nanoparticles merge to wires featuring good electrical conductivity. With this method less than 150 nm thin wires can be generated from 2 µm wide or smaller V‐grooves due to adapted dilution of particle content, self‐confinement in V‐grooves, shrinkage of line width during solvent evaporation, and sintering. After nanoimprinting, grooves made from PMMA are smoothened out by thermal reflow without affecting the wires. The resistivity of 300 µm long, 400 nm wires is similar to more conventional ink‐jet printed wires with 10–50 µm widths.