Direct Solution Deposition of Large-Area Non-Solvated Fullerene Single-Crystal Films for High-Performance n-Type Field-Effect Transistors

Fullerene (C₆₀) crystals have attracted considerable attention in the field of optoelectronic devices owing to their excellent performance as n-type semiconductor material. However, a challenge still remains unbeaten as to the continuous crystallization of non-solvated C₆₀ single-crystal films with high coverage and uniform alignment using low-cost solution techniques. Here, a facile bar coating method is used to prepare ribbon-shaped non-solvated C₆₀ crystals with a large area (up to centimeters) and high coverage (>95%) by precisely controlling the crystallization process from specific solvents. Benefiting from the non-solvated crystalline structure, well-distributed thickness, uniform morphological alignment, and crystallographic orientation, organic field-effect transistors fabricated from the C₆₀ single-crystal films exhibit a high average electron mobility of 2.28 cm² V^-1s^-1, along with the coefficient of variance (CV) as small as 13.6%. This efficient manufacturing method will lay a strong foundation for C₆₀ single-crystal films to fit into the future high-performance integrated optoelectronic application.