Patterning Liquid Crystalline Organic Semiconductors via Inkjet Printing for High‐Performance Transistor Arrays and Circuits
Xiaochen Fang,1,+ Jialin Shi,1,+ Xiujuan Zhang,1,* Xiaobin Ren,1 Bei Lu,1 Wei Deng,1,* Jiansheng Jie,1,2 and Xiaohong Zhang1,*
1 Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu 215123, P. R. China
2 Macao Institute of Materials Science and Engineering, Macau University of Science and Technology, Taipa, Macau SAR 999078, P. R. China
Liquid crystalline (LC) organic semiconductors having long-range-ordered LC phases hold great application potential in organic field-effect transistors (OFETs). However, to meet real device application requirements, it is a prerequisite to precisely pattern the LC film at desired positions. Here, a facile method that combines the technique of inkjet printing and melt processing to fabricate patterned LC film for achieving high-performance organic integrated circuits is demonstrated. Inkjet printing controls the deposition locations of the LC materials, while the melt processing implements phase transition of the LC materials to form high-quality LC films with large grain sizes. This approach enables to achieve patterned growth of high-quality 2,7-dioctyl-benzothieno[3,2-b]benzothiophene (C8-BTBT) LC films. The patterned C8-BTBT LC film-based 7 × 7 OFET array has 100% die yield and shows high average mobility of 6.31 cm2 V−1s−1, along with maximum mobility up to 9.33 cm2V−1s−1. As a result, the inverters based on the patterned LC films reach a high gain up to 23.75 as well as an ultrahigh noise margin over 81.3%. Given the good generality of the patterning process and the high quality of the resulting films, the proposed method paves the way for high-performance organic integrated devices.