High Performance Organic Thin-Film Transistor based on Amorphous A,B-Alternating Poly(arylenevinylene) Copolymers

Abstract

A series of amorphous polymers of poly(arylenevinylene) copolymers, in which heterocycles (furan, thiophene, selenophene) and dialkoxy phenylenes were alternatingly linked by vinylene unit, was prepared by the Horner−Emmons reaction. Because of high regularity of the polymer microstructure by selective formation of E olefin, the resulting polymers showed good interchain π−π stacking in thin film state despite being amorphous polymers. When the A,B-alternating poly(phenylene thiophene vinylene), in particular with the bis(heptoxy) group, was used as a semiconductor material in an organic thin-film transistor, the best hole mobility up to 0.03 cm2/(V s) was observed, which is one of the highest values recorded from amorphous polymer film. The mobility was even improved to 0.06 cm2/(V s) when the polymer was blended with well-dispersed single-wall carbon nanotubes (SWCNT). Although this mobility is lower than that from the best crystalline polymers, these amorphous polymers showed advantages such as the device performances being less sensitive to both their molecular weights and the choice of gate insulators than the typical crystalline polymers.