Abstract The carrier mobility is an important figure of merit and is sensitively influenced by the microstructure of semiconducting films such as crystallization and morphology. Here, a method of blending semiconducting small molecule 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) and insulating polymer binder is reported to well control the microstructures of blend semiconducting films. It is found that the insulating polymer in the blends prevents the dewetting of C8-BTBT from the SiO2 substrate and provides a platform for C8-BTBT molecules to segregate and crystallize at the air-film interface. By controlling the spinning speed, polymer type and ratio of the blend solution, it is possible to regulate the domain size and the surface roughness of C8-BTBT films, which in turn determines the performances of OTFTs. The bottom gate transistors based on C8-BTBT/polystyrene(PS) blend demonstrate excellent stability and a mobility up to 6.80 cm2/Vs due to the large domain size, smooth grain boundary and the phase-separated interface, which shows the potential applications in high-performance flexible and printed electronics.

中文翻译：

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用于高性能有机场效应晶体管的聚合物-小分子共混薄膜的可控微结构

摘要 载流子迁移率是一个重要的品质因数，受半导体薄膜的微观结构如结晶和形貌的影响很大。在这里，报道了一种将半导体小分子 2,7-二辛基 [1] 苯并噻吩并 [3,2-b][1] 苯并噻吩 (C8-BTBT) 和绝缘聚合物粘合剂混合的方法，可以很好地控制混合半导体薄膜的微观结构。结果表明，共混物中的绝缘聚合物可防止 C8-BTBT 从 SiO2 基材上脱湿，并为 C8-BTBT 分子在空气膜界面处分离和结晶提供平台。通过控制共混溶液的纺丝速度、聚合物类型和比例，可以调节C8-BTBT薄膜的畴尺寸和表面粗糙度，进而决定OTFT的性能。