Balancing the film strain of organic semiconductors for ultrastable organic transistors with a five-year lifetime

Xiaosong Chen; Zhongwu Wang; Jiannan Qi; Yongxu Hu; Yinan Huang; Shougang Sun; Yajing Sun; Wenbin Gong; Langli Luo; Lifeng Zhang; Haiyan Du; Xiaoxia Hu; Cheng Han; Jie Li; Deyang Ji; Liqiang Li; Wenping Hu

doi:10.1038/s41467-022-29221-8

Balancing the film strain of organic semiconductors for ultrastable organic transistors with a five-year lifetime

Nat Commun. 2022 Mar 16;13(1):1480. doi: 10.1038/s41467-022-29221-8.

Authors

Xiaosong Chen^#¹, Zhongwu Wang^#^{1

2}, Jiannan Qi^#¹, Yongxu Hu¹, Yinan Huang¹, Shougang Sun¹, Yajing Sun¹, Wenbin Gong³, Langli Luo⁴, Lifeng Zhang⁴, Haiyan Du⁵, Xiaoxia Hu⁵, Cheng Han², Jie Li¹, Deyang Ji¹, Liqiang Li^{6

7

8}, Wenping Hu^{1

9}

Affiliations

¹ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China.
² SZU-NUS Collaborative Innovation Center for Optoelectronic Science & Technology, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060, China.
³ School of Physics and Energy, Xuzhou University of Technology, Xuzhou, 221018, China.
⁴ Institute of Molecular Plus, Tianjin University, Tianjin, 300072, China.
⁵ Analysis and Testing Center of Tianjin University, Tianjin University, Tianjin, 300072, China.
⁶ Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, Institute of Molecular Aggregation Science, Tianjin University, Tianjin, 300072, China. lilq@tju.edu.cn.
⁷ Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, 215123, China. lilq@tju.edu.cn.
⁸ Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou, 350207, China. lilq@tju.edu.cn.
⁹ Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou, 350207, China.

^# Contributed equally.

Abstract

The instability of organic field-effect transistors (OFETs) is one key obstacle to practical application and is closely related to the unstable aggregate state of organic semiconductors (OSCs). However, the underlying reason for this instability remains unclear, and no effective solution has been developed. Herein, we find that the intrinsic tensile and compressive strains that exist in OSC films are the key origins for aggregate state instability and device degradation. We further report a strain balance strategy to stabilize the aggregate state by regulating film thickness, which is based on the unique transition from tensile strain to compressive strain with increasing film thickness. Consequently, a strain-free and ultrastable OSC film is obtained by regulating the film thickness, with which an ultrastable OFET with a five-year lifetime is realized. This work provides a deeper understanding of and a solution to the instability of OFETs and sheds light on their industrialization.