Organic thin-film transistors based on solution-processable benzodithiophene dimers modified with hexyl groups

Benzodithiophene dimers modified with hexyl groups (2C(6)-BDT-dimer) were investigated as solution-processable organic semiconductors for organic thin-film transistors (OTFTs). Since 2C(6)-BDT-dimer crystals have an anisotropic shape, flow coating was adopted to grow polycrystalline films. The flow-coated films were inferior to the vacuum-evaporated ones in terms of their crystallinity estimated from X-ray diffraction data. However, the hole mobility of the OTFTs with the flow-coated films, which was 1.7 cm(2)V(-1)s(-1) at maximum, was higher than that of the OTFTs with vacuum-evaporated films because the one-dimensional thin crystals of the flow-coated films were aligned in the flow-coating direction. (C) 2017 The Japan Society of Applied Physics