Photopatterned coumarin‐functionalized polymer dielectric for organic transistors and complementary inverters

Abstract

AbstractSolution‐processable and patternable polymer dielectrics are of great importance for the development of high‐performance flexible electronic devices, as the patterning process is essential to enhance performance and integration of devices. In this study, we report the photopatterning of a coumarin‐functionalized polymer gate dielectric, poly(7‐(4‐vinyl‐benzyloxyl)‐4‐methylcoumarin) (PVBMC), which was synthesized by introducing the photoreactive coumarin moiety in the position of the hydroxyl group of poly(4‐vinylphenol). Photopatterning of the PVBMC with a resolution of up to 50 μm was performed under ultraviolet light (365 nm) irradiation and the properties of the resulted photopatterned PVBMC were investigated. Pentacene (p‐type) and PTCDI‐C8 (n‐type) organic thin‐film transistors (OTFTs) with the patterned PVBMC were prepared. The resulting p‐ and n‐type OTFTs achieved maximum mobilities of 0.126 cm2/V/s and 1.15 × 10−3 cm2/V/s, respectively, with high operational stability. Organic complementary inverters were also demonstrated by integrating the p‐ and n‐type OTFTs on a single substrate. The resulting devices exhibited a gain (dVOUT/dVIN) of 12.6 and proper switching behavior up to 20 Hz. Our findings demonstrate the potential of this dielectric material for use in other flexible electronic applications.