Effect of contact resistance in organic field‐effect transistors

Abstract Contact resistance (RC) is universally present in organic field‐effect transistors (OFETs) and the performance of OFETs can be easily affected by RC, which will result in poor performances such as low mobility (μ), large threshold voltage (VT), and non‐ideal transfer/output characteristics. In this article, we provide a comprehensive review on the effects of RC in OFETs. We start with a brief introduction of the origin of RC and its effects on OFETs, followed by the commonly used methods for extraction of RC. Then, methods for reducing RC are thoroughly discussed. Especially, fabricating monolayer molecular crystal (MMC) OFETs is highlighted as one of the key solutions to reduce RC effectively. The final section describes the challenges in MMCs preparation and concludes with an outlook for further reducing RC to enhance the performances of OFETs.