Air-stable solution-processed n-channel organic thin film transistors with polymer-enhanced morphology

作者：He Zhengran; Shaik Shoieb; Bi Sheng; Chen Jihua; Li Dawen^*

来源：Applied Physics Letters, 2015, 106(18): 183301.

DOI：10.1063/1.4919677

N,Ns'-1H,1H-perfluorobutyl dicyanoperylenecarboxydiimide (PDIF-CN2) is an n-type semiconductor exhibiting high electron mobility and excellent air stability. However, the reported electron mobility based on spin-coated PDIF-CN2 Zfilm is much lower than the value of PDIF-CN2 single crystals made from vapor phase deposition, indicating significant room for mobility enhancement. In this study, various insulating polymers, including poly(vinyl alcohol), poly(methyl methacrylate) (PMMA), and poly(alpha-methylstyrene) (P alpha MS), are pre-coated on silicon substrate aiming to enhance the morphology of the PDIF-CN2 thin film, thereby improving the charge transport and air stability. Atomic force microscopy images reveal that with the pre-deposition of P alpha MS or PMMA polymers, the morphology of the PDIF-CN2 polycrystalline films is optimized in semiconducting crystal connectivity, domain size, and surface roughness, which leads to significant improvement of organic thin-film transistor (OTFT) performance. Particularly, an electron mobility of up to 0.55 cm(2)/V s has been achieved from OTFTs based on the PDIF-CN2 film with the pre-deposition of P alpha MS polymer.

• 出版日期2015-5-4