Meniscus-guided coating of continuous organic semiconductor crystalline thin-films via surface tension modulation

Meniscus-guided coating (MGC) enables facile production of large-area, unidirectionally oriented organic semiconductor crystalline thin-films. While efforts have been made in controlling the morphology of MGC-grown films, leading to improvements in device performance and uniformity along the coating direction, film continuity perpendicular to the coating direction has been largely overlooked. This work demonstrates that using high surface tension solvents significantly improved film continuity in the direction perpendicular to the coating, which was applicable to various organic semiconductors. Specifically, 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) film exhibited millimeter-sized domains and effective grain boundary contact, displaying single-crystal-like charge transport properties. Organic field-effect transistor arrays based on this two-dimensionally continuous, oriented crystalline thin-film showed enhanced mobilities and device-to-device uniformity in both parallel and perpendicular directions to the coating. The lowest coefficient of variation, 5.0%, was obtained for TIPS-PEN. This work provides a universal strategy for improving the continuity of MGC-grown films, promoting the practical application of OSSCs in organic electronics.