Ambipolar, high performance, acene-based organic thin film transistors

Area of Science:

• Organic electronics
• Materials science
• Semiconductor devices

Background:

• Ambipolar organic field-effect transistors (OFETs) are crucial for low-power electronics.
• Developing single-material ambipolar OFETs remains a significant challenge.
• Molecular design is key to achieving balanced charge transport.

Purpose of the Study:

• To present a high-performance ambipolar organic field-effect transistor (OFET) based on a single material.
• To demonstrate the potential of asymmetric linear acenes with fluorine substitution for ambipolar transport.
• To investigate the charge transport properties in both inert and ambient conditions.

Main Methods:

• Fabrication of OFETs using a low band gap, asymmetric linear acene with fluorine atoms.
• Device characterization under nitrogen atmosphere and ambient conditions.
• Surface treatment with octadecyltrimethoxysilane (OTS) and substrate heating at 60°C.

Main Results:

• Achieved high charge carrier mobilities for both holes and electrons in a single material.
• Reported hole mobility of up to 0.12 cm²/V·s in ambient conditions.
• Observed electron mobility up to 0.37 cm²/V·s in nitrogen, with electron transport quenched in ambient.
• Demonstrated successful device fabrication on OTS-treated surfaces.

Conclusions:

• The developed single-material ambipolar OFET shows promise for advanced electronic applications.
• Fluorine substitution effectively lowers molecular orbital energies, facilitating electron injection.
• Device performance is sensitive to environmental conditions, highlighting the need for further encapsulation strategies.