Ink-jet and gravure printed electronics

Abstract

Drop-on-demand ink-jet printing enables rapid, digital prototyping of electronic circuits based on solution-processable conductors, semiconductors and dielectrics. Through this technique we have developed fully printed, mechanically flexible, n- and p- type field-effect transistors (FETs) based on organic semiconductors. Design rules and device models have been extracted based on these printed FETs and used to produce complementary logic circuits such as shift registers and threshold detectors. These circuits can provide the signal processing capabilities required for print production of highly functional flexible sensing systems for applications such as health monitoring and item level tracking. In order to demonstrate such printed systems, the circuits have been integrated with printed sensors, memories, and power sources. In addition to ink-jet we have also investigated gravure printing for the fabrication of such electronic devices. This master-based technique allows for high resolution, rapid roll-to-roll production of electronics, proving a potential route to manufacturing of printed systems. We have also transferred the materials and designs from the lab-scale to a production-scale gravure press which presents additional challenges such as material selection and ink usage.