The application of a high-k polymer in flexible low-voltage organic thin-film transistors

Abstract

Although much progress has been made in the study of high-mobility organic semiconductors in recent years, one major challenge for organic thin film transistors (OTFTs) in real applications is the relatively high operating voltage, which is mainly related to the gate dielectric of the OTFT. Here we show the application of a high-k poly(vinylidene fluoride-trifluoroethylene-chlorofloroethylene) (P(VDF-TrFE-CFE)) as the gate dielectric of flexible low-voltage pentacene OTFTs for the first time. The performance of the OTFTs is optimized by modifying the surface of P(VDF-TrFE-CFE) films with various thin polymer films by a solution process. The flexible OTFTs show excellent performance at the operating voltage of 4 V and good stability after 1000 bending tests. It is expected that P(VDF-TrFE-CFE) is a suitable gate dielectric for low-voltage OTFTs based on various small-molecule organic semiconductors because P(VDF-TrFE-CFE) terpolymer films can be easily modified with different thin polymer films by a solution process.