Organic thin film transistors using 6,13-bis(tri-isopropylsilylethynyl)pentacene embedded into polymer binders

Abstract

The active channel material of an organic thin film transistor (OTFT), 6,13-bis(tri-isopropylsilylethynyl)pentacene (TIPS pentacene), is a functionalized pentacene designed to enhance both the solubility and solid-state packing of the pentacene. In this work, in order to improve device performance, three types of polymer binders-poly(alpha-methylstyrene) (PAMS), poly(4-vinylbiphenyl) (PVBP), and poly(triarylamine) (PTAA)-were employed to fabricate OTFT devices with organic soluble TIPS pentacene. These binders improved film formation in a large area uniformly and helped the TIPS pentacene to form a stronger binding between source/drain electrodes onto dielectric layer. Thus, device performance was highly improved due to improvement of interfacial contact and an increase in the charge transfer in the active channel. OTFTs using TIPS pentacene with PAMS, PVBP, and PTAA for field effect mobilities in the saturation regime have 5x10(-3), 8x10(-3), and 2.7x10(-2) cm(2)/V s, respectively.