Hole Mobility Enhancement in Benzo[1,2-b:4,5-b']Dithiophene-Based Conjugated Polymer Transistors through Directional Alignment, Perovskite Functionalization and Solid-State Electrolyte Gating.

Tunability in electronic and optical properties have been intensively explored for developing conjugated polymers and its applications in organic and perovskite-based electronics. Particularly, charge carrier mobility of conjugated polymer semiconductors has been deemed to be a vital figure-of-merit for achieving high performance organic field-effect transistors (OFETs). In this study, we demonstrate the systematic hole carrier mobility improvement of benzo[1,2-b:4,5-b']dithiophene-based conjugated polymer in perovskite-functionalized organic transistors. In conventional OFETs with a poly(methyl methacrylate) (PMMA) gate dielectric, we measured improvements in hole mobility of 0.019 cm 2 V -1 s -1 using an off-center spin-coating technique, which exceeded those of on-center counterparts (0.22 ± 0.07 × 10 -2 cm 2 V -1 s -1 ). Furthermore, the mobility was drastically increased by adopting solid-state electrolyte gating, corresponding to 2.99 ± 1.03 cm 2 V -1 s -1 for the control, and the best hole mobility was 8.03 cm 2 V -1 s -1 (average ≈ 6.94 ± 0.59 cm 2 V -1 s -1 ) for perovskite-functionalized organic FETs with a high current on/off ratio of > 10 6 . The achieved device performance would be attributed to the enhanced film crystallinity and charge carrier density in the hybrid perovskite-functionalized organic transistor channel, resulting from the high-capacitance electrolyte dielectric. This article is protected by copyright. All rights reserved.