A Self-Aligned Strategy for Printed Electronics: Exploiting Capillary Flow on Microstructured Plastic Surfaces

Printing is a promising route for high-throughput processing of electronic devices on large-area, flexible substrates by virtue of its integration into roll-to-roll production formats. However, multilayered electronic devices require materials registration with micrometer-level tolerances, which is a serious challenge for continuous manufacturing. Here, a novel, self-aligned manufacturing approach is introduced that allows precision patterning of multilayered electronic devices by inkjet printing on microimprinted plastic substrates. Materials registration is achieved automatically by sequential deposition of liquid inks into multilevel trench networks on the substrate surface using capillary forces. By creating suitable multitier capillary networks, fully self-aligned fabrication of all the major building blocks of an integrated circuit, including resistors, capacitors, transistors, and crossovers, with excellent yields and performance metrics is demonstrated. The current status of inkjet and imprint technologies suggests that this self-aligned manufacturing strategy can be scaled up to large-area substrates with integration densities greater than 1000 devices cm⁻².