Affiliation:
1. Tianjin Key Laboratory of Film Electronic and Communication Devices School of Integrated Circuit Science and Engineering Tianjin University of Technology Tianjin 300384 China
2. Department of Chemistry Institute of Molecular Aggregation Science Key Laboratory of Organic Integrated Circuits Ministry of Education Tianjin Key Laboratory of Molecular Optoelectronic Sciences Tianjin University Tianjin 300072 China
3. Shenzhen Key Laboratory of New Information Display and Storage Materials College of Materials Science and Engineering College of Physics and Optoelectronic Engineering Shenzhen University Shenzhen 518060 China
Abstract
AbstractThe key roles of electrode/semiconductor and semiconductor/dielectric interfaces play in the ideality of organic field‐effect transistors (OFETs) by traditional device preparation technologies are not yet fully understood, which severely limits progress in the design of molecules, the understanding of transport mechanisms, and the circuit applications of OFETs. Herein, at a quantitative level, the origin of nonideal current–voltage (I–V) curves and possibly overestimated mobility in single‐crystal OFETs is revealed, including contact resistance (Rc), charge trapping, and scattering at interfaces of devices. Impressively, an efficient interface collaborative strategy, which consists of transferred “doped” electrodes with tunable contact “doping” localized regions at the source‐drain contacts and polymer‐modified SiO2 with suitable surface polarity (γsp) is further demonstrated that have great advantages in the construction of ideal high mobility devices. Also, an interesting double‐edged sword effect of γsp of dielectric on the ideality of OFETs is observed. The dielectric with a lower γsp can result in higher mobility, while too low γsp would degrade the device ideality due to significant effect of charge scattering. The findings not only provide new perspectives and strategies to construct ideal OFETs but also offer useful guidance to correctly evaluate organic semiconductor materials.
Funder
National Natural Science Foundation of China
Key Technologies Research and Development Program