Fluorine substitution influence on benzo[2,1,3]thiadiazole based polymers for field-effect transistor applications.

Four conjugated copolymers with a donor/acceptor architecture comprising 4,4-dihexadecyl-4H-cyclopenta[1,2-b:5,4-b']dithiophene as the donor structural unit and benzo[2,1,3]thiadiazole fragments with varying degrees of fluorination as the acceptor structural units have been synthesized and characterized. It has been shown that the energy levels were decreased after the fluorine substitution. The field-effect charge carrier mobility was similar for all polymers with less than an order of magnitude difference between different acceptor units.