25th anniversary article: Organic field-effect transistors: The path beyond amorphous silicon

Abstract

Over the past 25 years, organic field-effect transistors (OFETs) have witnessed impressive improvements in materials performance by 3-4 orders of magnitude, and many of the key materials discoveries have been published in Advanced Materials. This includes some of the most recent demonstrations of organic field-effect transistors with performance that clearly exceeds that of benchmark amorphous silicon-based devices. In this article, state-of-the-art in OFETs are reviewed in light of requirements for demanding future applications, in particular active-matrix addressing for flexible organic light-emitting diode (OLED) displays. An overview is provided over both small molecule and conjugated polymer materials for which field-effect mobilities exceeding > 1 cm2 V-1 s-1 have been reported. Current understanding is also reviewed of their charge transport physics that allows reaching such unexpectedly high mobilities in these weakly van der Waals bonded and structurally comparatively disordered materials with a view towards understanding the potential for further improvement in performance in the future. The mobility of organic field-effect transistors (OFETs) has improved dramatically over the past 25 years, and now exceeds that of amorphous silicon. OFETs are being used in products such as flexible electronic paper displays. Current understanding of the charge transport physics that allows such unexpectedly high mobilities to be reached in van der Waals-bonded molecular and polymeric semiconductors is reviewed. © 2014 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.