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Date/Time: Oct 22, 2025, 13:00-14:00
Venue: Online (Microsoft Teams Webinar)
Lecturer: Prof. Tatsuo Hasegawa (University of Tokyo)
“Organic Electronics Fully Utilizes Layered Molecular Ordering”
Admission:Free
Registration:https://forms.office.com/r/i3fP5QhYmj
Registration Deadline: Registration will be accepted until just before the seminar starts.
If you register in advance, a reminder with the link for participation will be sent to your registered e-mail address on October 21.

【Abstract】 The development of organic semiconductors and molecular conductors has underscored the critical importance of highly ordered intermolecular structures as the basis for diverse electronic functionalities. While phenomena such as superconductivity and topological effects in CT complexes have been observed, they are typically limited to tiny bulk molecular single crystals, severely limiting practical device integration. In contrast, recent advances have demonstrated that molecular ordering can be effectively exploited to fabricate high-performance, large-area organic single-crystal thin-film devices. Notably, organic semiconductors composed of rod-like molecules with π-conjugated backbones and linear alkyl chains exhibit exceptionally high layered crystallinity, enabling the formation of ultrathin single-crystal films with molecular-level thickness over wafer-scale areas via solution coating techniques that promote molecular self-assembly into layered structures. Furthermore, by forming an ultraclean semiconductor–insulator interface through semiconductor solution coating on a highly liquid-repellent insulating layer, we have realized high-performance FETs that exhibit extremely steep switching behavior—approaching the theoretical limit—at low operating voltages and with excellent stability. In this presentation, we will focus on the mechanism of layered molecular arrangements that allow these developments. We elucidate the origin of layered molecular ordering through high-precision calculations of intermolecular interactions and apply these insights to the prediction of layered crystal structures. We also discuss the underlying mechanism to achieve large-scale layered molecular arrangements by leveraging metastable phases, such as layered liquid-crystal states in solution or melt phases.