Self-assembled Monolayers Mediated Charge Injection For High Performance Bottom-contact Pory(3,3''-didodecylquaterthiophene) Thin-film Transistors

摘要

Device performance of bottom-contact poly(3,3"'-didodecylquaterthiophene) (PQT-12) thin-film transistors (TFTs) was significantly improved via surface-modification of Au source-drain (S-D) electrodes with 1-decanethiol and 1H,1H,2H,2H-perfluorodecanethiol self-assembled monolayers (SAMs). By improving the PQT-12 morphology and modulating the Schottky barrier at electrode/PQT-12 contacts, the thiol SAMs chemisorbed onto Au surfaces can improve the charge carrier injection at electrode/PQT-12 contacts and result in dramatic enhancements in device mobilities. Device mobilities up to 0.09 and 0.19 cm~2 V~(-1) s~(-1) were obtained in high performance bottom-contact PQT-12 TFTs with 1-decanethiol and 1H,1H,2H,2H-perfluorodecanethiol SAMs surface-modified Au S-D electrodes, compared with 0.015 cm~2 V~(-1) s~(-1) in PQT-12 TFTs with bare Au electrodes. This work may provide a simple path to the fabrication of high performance, low-cost, and solu-tion-processable bottom-contact OTFTs using fine lithography technology.