Wafer-Scale Growth of Aligned C-60 Single Crystals via Solution-Phase Epitaxy for High-Performance Transistors

Fullerene (C-60) single crystals with exceptionally low defects and nearly perfect translational symmetry make them appealing in achieving high-performance n-type organic transistors. However, because of its natural 0D structure, control over continuous crystallization of C-60 over a large area is extremely challenging. Here, the authors report a solution-phase epitaxial approach for wafer-scale growth of continuously aligned C-60 single crystals. This method enables the rational control of the density of nucleation event at meniscus front by confining the size and shape of meniscus with a microchannel template. In this case, a single nucleus as seed crystal can be formed at the front of meniscus, and then epitaxial growth from the seed crystal occurs with continuous retreat of the meniscus. As a result, highly uniform C-60 single-crystal array with ultralow defect density is obtained on 2-inch substrate. Organic field-effect transistors made from the C-60 single-crystal array show a high average electron mobility of 2.17 cm(2) V-1 s(-1), along with a maximum mobility of 5.09 cm(2) V-1 s(-1), which is much superior to the C-60 polycrystalline film-based devices. This strategy opens new opportunities for the scalable fabrication of high-performance integrated devices based on organic crystals.