High‐mobility Ambipolar Transistors and High‐gain Inverters from a Donor–Acceptor Copolymer Semiconductor

Abstract

Ambipolar organic field-effect transistors (OFETs), which are capable of both p- and n-channel operations, are gaining attention as an alternative approach to mimicking complementary metal-oxide semiconductor (CMOS) digital integrated circuits for achieving high-performance and cost-effective circuits in organic electronics. [1‐13] Low power dissipation and high performance are some of the major advantages of CMOS technology over non-complementary ones. [14] Power consumption is minimized in CMOS circuits because the component transistors are selectively turned on only when the circuit is switching, otherwise they are off at the steady state. The better performance of a CMOS circuit in terms of sharp switching and high noise immunity arises because every elemental transistor actively contributes to the function of the circuit. [14] Most efforts towards CMOS-like circuits in organic electronics have focused on utilizing distinct p- and n-type semiconductors. [1,15] However, the necessity of lateral patterning of semiconductors in CMOS circuits makes device fabrication on a common substrate a very complex process. Ambipolar OFETs represent an approach to high-performance CMOS-like circuits that minimize patterning and complex fabrication processes. [1] Ambipolar transistors are also of interest in fundamental studies of charge transport in organic semiconductors [1,6,16] as well as the development of efficient light-emitting transistors. [8,17‐21]