High-performance polymer tfts printed on a plastic substrate

Abstract

High-performance poly (3-hexylthiophene) (P3HT) thin-film transistors array was fabricated on a plastic substrate by employing micro-contact printing process. The microcontact printing process, which uses a silicon elastomer stamp, enables the patterning of polymer layers without any photolithography process. As the gate dielectric, spun polyimide, and low-temperature ion-beam deposited silicon dioxide layers were used, forming a dual-layer structure. It is found out that the polymide layer improves the surface roughness of the dielectric and accordingly brings about enhanced device performance. Additionally, by using O2 plasma treatment, both higher drain current and carrier mobility were obtained simultaneously. Changes in the surface states of the source-drain electrodes and the morphology of the dielectric are proposed to account for the observed improvements. Based on the experiments, we built a high-performance plastic-based P3HT transistors array including 0.02 cm2 V ·s in carrier mobility and on/off current ratio about 103 ~ 104.