Adv. Funct. Mater.: A Facile Method for the Growth of Organic Semiconductor Single Crystal Arrays on Polymer Dielectric toward Flexible Field-Effect Transistors

Title：

A Facile Method for the Growth of Organic Semiconductor Single Crystal Arrays on Polymer Dielectric toward Flexible Field-Effect Transistors

Authors：

Wanqin Zhao, Jiansheng Jie*, Qi Wei, Zhengjun Lu, Ruofei Jia, Wei Deng, Xiujuan Zhang, Xiaohong Zhang*

Institutions：

Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123,P.R.China.

Abtstract：

Polymer dielectrics with intrinsic mechanical flexibility are considered as a key component for flexible organic feld-effect transistors (OFETs). However, it remains a challenge to fabricate highly aligned organic semiconductor single crystal (OSSC) arrays on the polymer dielectrics. Herein, for the frst time, a facile and universal strategy, polar surface-confned crystallization (PSCC), is proposed to grow highly aligned OSSC arrays on poly(4-vinylphenol) (PVP) dielectric layer. The surface polarity of PVP is altered periodically with oxygenplasma treatment, enabling the preferential nucleation of organic crystals on the strong-polarity regions. Moreover, a geometrical confnement effect of the patterned regions can also prevent multiple nucleation and misaligned molecular packing, enabling the highly aligned growth of OSSC arrays with uniform morphology and unitary crystallographic orientation. Using 2,7-dioctyl[1]benzothieno[3,2-b]benzothiophene (C₈-BTBT) as an example, highly aligned C₈-BTBT single crystal arrays with uniform molecular packing and crystal orientation are successfully fabricated on the PVP layer, which can guarantee their uniform electrical properties. OFETs made from the C₈-BTBT single crystal arrays on flexible substrates exhibit a mobility as high as 2.25 cm² V^-1 s^-1, which has surpassed the C₈-BTBT polycrystalline flm-based flexible devices. This work paves the way toward the fabrication of highly aligned OSSCs on polymer dielectrics for high-performance, flexible organic devices.

IF：

15.621

Link：

 https://doi.org/10.1002/adfm.201902494

Editor: Wenchang Zhu