Poly(α-methyl styrene) polymer additive for organic thin film transistors

While great progress has been achieved in the research of various solution-processed organic semiconductors, the randomized crystal orientations and charge carrier mobility variations have posed tremendous challenges to implement the organic semiconductors for organic electronic device applications. Among the miscellaneous polymer additives reported to tune the crystal growth and modulate charge transport, poly(α-methyl styrene) (PαMS) has been extensively studied for its capability to improve semiconductor crystallization, reduce bulk crystal misorientation, induce phase segregation, enhance morphological uniformity and boost electrical performance of organic thin film transistors and organic electronic devices. In the first section of this article, we review the recent progress of organic electronics and highlight the crystal misorientation and mobility variation as the challenges that need to be overcome. Then, the various merits from mixing polymeric additives with organic semiconductors are discussed. In the second section, we provide an overview of the previous works that employ PαMS for regulating the crystal orientation alignment and modulating charge transport of miscellaneous solution-processed small-molecular organic semiconductors including 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene) and 2,8-difluoro-5,11-bis(triethylsilylethynyl)anthradithiophene (diF-TESADT). By discussing these important examples, we intend to demonstrate that PαMS can be versatilely implemented to improve other new organic semiconductor crystallization and mobility for high-performance organic electronic applications.