Anisotropic Charge-Carrier Transport in High-Mobility Donor-Acceptor Conjugated Polymer Semiconductor Films.

Many high-performance solution-processable polymer thin-film transistors (PTFTs) have been reported. This contribution presents a comparative study of oriented films that have been deposited by means of solution shearing (SS) with charge-carrier transport anisotropy for PTFTs based on a diketopyrrolopyrrole-thiazolothiazole donor-acceptor copolymer (PDPPTzBT). The maximum field-effect mobility of the SS film of PDPPTzBT was 10.00 cm2 V−1 s. We also blended a solution of PDPPTzBT with a solution of polystyrene (PS). Solvent vapor annealing (SVA) lateral phase separation was adopted to block carrier transport in the direction of π-π stacking, and further evidence of charge transport anisotropy was provided. Highly oriented polymer films will further influence the carrier transport anisotropy and promote carrier transport along the backbone, and the performance of the field-effect transistor is thus improved. [ABSTRACT FROM AUTHOR]