Enhancing the Uniformity of Organic Field-Effect Transistors by a Single-Crystalline Layer-Controlled Active Channel

Despite remarkable improvement in the mobility of the organic field-effect transistors (OFETs) being achieved in past decades, the uniformity in electrical performance remains ambiguous, impeding their implantation in organic integrated circuits. The coefficient of variance (CV) in mobility of reported OFETs is typically larger than 8%, which is not adequate for building medium-to-large scale integrated circuits. In this work, it is shown that utilizing single-domain molecular monolayer crystals as the active channel can largely enhance the uniformity of OFETs. Benefiting from the sole molecular layer with long-range ordering, the OFETs exhibit uniformities in both channel transport and charge injection, thereby giving rise to a high average mobility of 11.64 cm² V^-1 s^-1 and CV of only 2.57%. Statistical transmission length method evaluation is conducted, covering channel length from 3 to 21 µm, channel width from 90 to 170 µm, and a total OFET number of 370. The low contact resistance of 79.00 ± 7.00 Ω cm and high intrinsic mobility of 12.36 ± 0.45 cm² V^-1 s^-1 are acquired with very high accuracy and reliability. As such, this work provides a practical way to enhance the uniformity of OFETs by a single-crystalline layer-controlled active channel toward their applications in integrated circuits.