High performance polymer field‐effect transistors based on polythiophene derivative with conjugated side chain |
| |
| Authors: | Youjun He Weiping Wu Yunqi Liu Yongfang Li |
| |
| Institution: | 1. Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China;2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China |
| |
| Abstract: | Poly(3‐2‐(5‐hexyl‐2‐thienyl) ethenyl]‐2,2′‐bithiophene) ( P2 , see Scheme 1 ) with conjugated thienylvinyl side chain was synthesized by copolymerization of the thiophene units with and without conjugated side chain with Pd‐catalyzed Stille coupling method. For comparison, P1 with the hexyl side chain instead of conjugated side chain was also synthesized. P2 film shows broad absorption in the visible region with absorption edge at about 700 nm. The solution‐processed polymer field‐effect transistors were fabricated and characterized with bottom gate/top contact geometry. The organic field‐effect transistors (OFET) based on P2 showed an average hole mobility of about 0.034 cm2/Vs (the highest value reached 0.061 cm2/Vs) upon annealing at about 180 °C for 30 min, with a threshold voltage of ?1.15 V and an on/off ratio of 104 with n‐octadecyltrichlorosilane (OTS) modified SiO2 substrate. In comparison, the OFET based on P1 displayed a hole mobility of 8.9 × 10–4 cm2/Vs and an on/off ratio of 104 with OTS modified SiO2 substrate. The results indicate that the polythiophene derivative with conjugated thienylvinyl side chain is a promising polymer for the application in polymer field‐effect transistors. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5304–5312, 2009 |
| |
| Keywords: | charge transport conjugated polymers conjugated side chain hole mobility organic field effect transistors polythiophene derivatives UV– vis spectroscopy |
|
|
