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

Solution-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 mu m was performed under ultraviolet light (365 nm) irradiation and the properties of the resulted photopatterned PVBMC were investigated. Pentacene (p-type) and PTCDI-C-8 (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 cm(2)/V/s and 1.15 X 10(-3) cm(2)/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 (dV(OUT)/dV(IN)) 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.