High mobility organic thin-film transistors based on p-p heterojunction buffer layer

The p-p heterojunction of 5, 6, 11, 12-tetraphenylnaphthacene/vanadyl phthalocyanine, which has been used as the buffer layer, is demonstrated. The highest field-effect mobility is 5.1 cm2/Vs, which is one of the highest reported for polycrystalline rubrene thin film transistors. Current versus voltage characteristics of heterojunction diodes are utilized to investigate the charge injection mechanism, revealing the factors that bring about the improvement of carrier injection and the reduction of contact resistance. These results suggest that our approach is very promising to fabricate high performance organic thin-film transistors for practical applications in organic electronics.