Scalable Printing of High‐Resolution Flexible Transparent Grid Electrodes Using Directed Assembly of Silver Nanoparticles

Abstract

AbstractNext‐generation optoelectronic applications such as virtual and augmented reality systems need ultrahigh resolution displays with a greater number of smaller, tightly packed pixels to avoid issues such as aliasing and the screen‐door effect. High‐resolution grid electrodes with submicron or nanoscale line widths are ideal for successful integration of more pixels with smaller light‐emitting diodes. Solution‐printed metal grid electrodes are a cost‐effective alternative to the vapor‐deposited indium tin oxide or metal grid transparent electrodes, but a scalable method to print high‐resolution (≤2 µm line width) grid structures over large flexible or rigid substrates remains elusive. A versatile, scalable, directed assembly process is presented for printing high‐resolution grid transparent conductive electrodes under ambient conditions using silver nanoparticles over large substrates. Silver grid electrodes with line widths of 2 µm and 300 nm are printed using the described process. The aspect ratio and hence the electrical properties of the transparent electrodes are tailored using the withdrawal speed and the depth of the patterned photoresist. A high‐performance grid electrode with a sheet resistance of 43 Ω sq−1 and an average transmittance of ≈93% to visible light is realized. The printed grid electrodes are also remarkably flexible and are suited to a wide variety of conventional and emerging optoelectronic applications.