Highly fluorinated polyimide gate dielectric for fully transparent aqueous precursor derived In–Zn oxide thin-film transistors

Abstract

The development of flexible dielectric polymers with robust temperature durability, excellent mechanical properties and high transparency will be of great significance for the soft electronics. In current work, a highly fluorinated polyimide (hF-PI) material was successfully synthesized. By using (3-Aminopropyl) triethoxysilane as “bridge” and controlling the humidity rigidly, transparent polyimide films with smooth surface and tight adhesion to a strong substrate was prepared. As well, the mechanism of non-transparent hF-PI film formation in an ambient atmosphere at a low concentration was clarified. Based on the high temperature resistance of the hF-PI, the indium–zinc oxide (IZO) semiconductor film was successfully prepared on hF-PI film by the simple eco-friendly aqueous route. The IZO thin-film transistor using hF-PI film as insulating layer exhibited highly transparent and excellent electrical performance in the carrier mobility and the on/off current ratio. In addition, the operating voltage was greatly reduced by physically doping with carbon nanotube, while the devices still maintained good transparency.