Vinylene-Linked Oligothiophene-Difluorobenzothiadiazole Copolymer for Transistor Applications

Casey, Abby; Han, Yang; Gann, Eliot; Green, Joshua P.; McNeill, Christopher R.; Anthopoulos, Thomas D.; Heeney, Martin

ACS APPLIED MATERIALS & INTERFACES

2016

The synthesis of the novel donor–acceptor monomer 4,7-bis[(E)-2-(5-bromo-3-dodecylylthiophen-2-yl)ethenyl]-5,6-difluoro-2,1,3-benzothiadiazole (FBT-V2T2) is reported. Polymerization with 4,4′-ditetradecyl-5,5′-bistrimethylstannyl-2,2′-bithiophene afforded a highly crystalline polymer that aggregated strongly in solution. Polymer films were well ordered resulting in high performance field-effect transistors with low onset voltages, negligible hysteresis, high channel current on/off ratios, and peak hole mobilities of up to 0.5 cm2 V–1 s–1. Notably the transistors exhibited close to ideal behavior with extracted mobilities almost independent of gate of voltage.