Chemical Research in Chinese Universities ›› 2026, Vol. 42 ›› Issue (4): 1229-1236.doi: 10.1007/s40242-026-6015-2

• Research Articles • Previous Articles     Next Articles

Modulating Organic Transistor Performance by Optimizing Organic-Organic Interface Charge Transfer

SHEN Xueli1, XUE Di1, YIN Yao1, YAN Chi1, WANG Wenchong1, XIE Miao1, HUANG Lizhen1, CHI Lifeng1,2   

  1. 1. Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou 215123, P. R. China;
    2. Macao Institute of Materials Science and Engineering (MIMSE), MUSTSUDA Joint Research Center for Advanced Functional Materials, Macau University of Science and Technology, Taipa 999078, Macao, P. R. China
  • Received:2026-01-13 Revised:2026-03-12 Online:2026-08-01 Published:2026-07-28
  • Contact: CHI Lifeng,E-mail:chilf@suda.edu.cn;HAUNG Lizhen,E-mail:lzhuang@suda.edu.cn;WANG Wenchong,E-mail:wcwang@suda.edu.cn E-mail:chilf@suda.edu.cn;lzhuang@suda.edu.cn;wcwang@suda.edu.cn
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (Nos. 22222205, 52173176), the Science and Technology Development Fund of Macao, China (No. 0063/2024/RIA1), and the Project of the Suzhou Key Laboratory of Surface and Interface Intelligent Matter, China (No. SZS2022011).

Abstract: Organic heterojunctions have demonstrated significant potential in modulating the properties and performance of organic electronic devices through interfacial charge effects. However, these effects are critically dependent on the electronic structure and film morphology, which can lead to unpredictable variations in device performance. In this study, we systematically investigated the interfacial charge transfer between two thiophene derivatives and achieved optimized organic field-effect transistor (OFET) performance through interface engineering. The heterojunction is constructed via 2,7-dihexyl-dithieno[2,3-d;2',3'-d']benzo[1,2-b;4,5-b']dithiophene (DTBDT-C6) and dicyanovinylterthiophene (DCV3T), with density functional theory (DFT) calculations revealing distinct HOMO-LUMO distributions that facilitate charge transfer at the interface. This is further confirmed through in situ photoluminescence spectroscopy, X-ray photoelectron spectroscopy (XPS) and Kelvin probe force microscopy (KPFM). The OFET performance exhibits a pronounced thickness dependence, where both the off-state current and charge mobility initially increase but subsequently decrease with increasing DCV3T thickness. This behavior is attributed to the competing effects of enhanced conductivity and thickness-dependent injection barriers at the interface. By spatially confining DCV3T to an optimal thickness at the electrode-semiconductor interface together with dielectric surface modification, we achieved a balanced performance with a super on/off current ratio of 107 and a high mobility over 1 cm2·V-1·s-1. These results underscore the importance of heterojunction engineering in advancing device operation.

Key words: Organic field-effect transistor (OFET), Organic heterojunction, Interface charge transfer, Spatially confining