Fabrication of organic field effect transistors using directed assembled silver nanoparticle source/drain electrodes

Abstract Organic field effect transistors (OFETs) have attracted considerable attention in recent years owing to their unique properties of cost-effectiveness, lightweight, flexibility, and biocompatibility. Commercial OFETs are mainly fabricated utilizing traditional micro/nano fabrication techniques which require high vacuum conditions and sophisticated equipment, while emerging solution-based printing techniques have limited resolution and poor pattern fidelity. Here, we report the fabrication of bottom-gate bottom-contact OFETs on silicon/silicon dioxide substrates utilizing silver patterns as source/drain electrodes and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) as semiconducting channels. The silver patterns are fabricated using the surface energy-directed assembly (SEDA) process, while the C8-BTBT channels are fabricated using a combination of spin-coating and solvent vapor annealing processes. The fabricated OFETs exhibit p-type electrical behavior, achieving a high on/off current ratio of 10 7 and an average field-effect mobility of 6.24 × 10 −2 cm 2 V −1 s −1 . The normal operation of the OFETs demonstrates the applicability of silver nanoparticles in source/drain electrodes. In addition, the applicability of utilizing the SEDA process for cost-effective fabrication of source/drain electrodes is demonstrated.