Ultrafast Direct Writing of Polymers as a Simple Fabrication Method for Organic Electrochemical Transistors

Organic ionic/electronic conductors (OMIECs) offer a promising alternative to metals and inorganic semiconductors for direct interfacing between human-made electronics and biological tissues. A device that takes advantage of the mixed ionic/electronic conductivity of OMIEC materials is the organic electrochemical transistor (OECT). High-density OECTs are typically fabricated using costly cleanroom-based lithography and complex lift-off processes. To simplify the fabrication of OECTs, we propose laser direct writing of conjugated polymers using a commercial two-photon polymerization 3D printer. Ultrafast laser direct writing allows single-digit micrometer resolution and high-speed processing, thereby enabling a cost-effective and simple fabrication process.