Controlled growth of organic single-crystal arrays on hydrophobic substrate surface for high-performance transistors

Optoelectronic devices such as organic field-effect transistors (OFETs) and organic light-emitting diodes are expected to achieve low-cost flexible optoelectronic applications, but the low-cost potential depends on the capability of large-area deposition of organic semiconducting single-crystal (OSSC) arrays based on solution methods. However, poor surface-wetting behavior and sophisticated fluid kinetics limit solution deposition of large-scale OSSC arrays. Herein, the wetting-ability and fluid drying dynamics were improved by adding trace surfactants, and the affinity between organic solution and hydrophobic surface was also enhanced. In addition, the groove structures of polydimethylsiloxane templates were used as confined spaces for the nucleation, crystallization, and growth of OSSCs, and finally an OSSC array over large areas was prepared. This strategy has good universality for materials and patterns. OFETs based on the OSSC array show good performance and uniformity. These illustrations will provide more opportunities for integrated applications of organic single-crystal devices.