Lateral Homoepitaxy Growth of Organic Single-Crystal Arrays for Large-Scale and High-Performance Organic Field-Effect Transistors

Abstract

Epitaxial single-crystal semiconductors, serving as the backbone of electronic devices, are the cornerstones of modern electronics. Solution-processable organic semiconductors provide the potential for the epitaxial growth of their single crystals using low-cost and scale-up solution-based methods. However, current epitaxy methods for the growth of organic semiconducting single crystals (OSSCs) are plagued by limited scalability and controllability, impeding their integration into large-area electronic platforms. Here, we report a lateral homoepitaxy growth method that can be compatible with scalable solution printing techniques, thus obtaining centimeterscale OSSC arrays. We engineer a selective wettability area to enable the formation of well-aligned seed crystals and unlock a stable lateral homoepitaxy epitaxy process. Using this approach, we achieve purely aaxis oriented 2,7-dioctyl[1]-benzothieno [3,2-b][1]benzothiophene (C 8 −BTBT) OSSC arrays with high-uniformity morphology and low trap carrier density of 2.8 × 10 17 cm −3 eV −1 . Leveraging these superiorities, 100 organic field-effect transistors (OFETs) over a centimeter scale developed by the OSSC arrays exhibit a 520% improved average mobility of 10.4 cm 2 V −1 s −1 and a low 14.6% variation in carrier mobility. Our approach will lay a strong foundation for OSSCs to fit into the manufacturing of large-area organic single-crystal electronics.