Interaction of Organic Semiconductors and Graphene Materials in the Source-Drain Channel of Field-Effect Transistors

This study investigates the interfacial interactions between two organic semiconductors (tetrathiafulvalene (TTF) and hexaazatriphenylene-hexacarbonitrile (HAT-CN)) and graphene-based materials (nanocrystalline graphite and vertically aligned graphene) used in Field-Effect Transistors (FETs). The interaction mechanisms, including π–π stacking, charge transfer, and dipole–dipole interactions, were explored through SEM imaging, Raman and FTIR spectroscopy, and FET transfer characteristics. Spectroscopic data confirmed strong π–π and charge-transfer interactions, with distinct modifications in graphene structural and electronic features. Electrical measurements revealed significant modulation of channel conductivity, confirming effective surface functionalization. These findings provide a framework for engineering high-performance organic/graphene hybrid interfaces in electronic devices and biosensors. Importantly, the results demonstrate that molecular design and interfacial control at the nanoscale can be strategically used to modulate charge transport in graphene-based FETs. This approach opens new pathways for developing tunable, molecule-specific biosensors and nanoelectronic platforms with enhanced sensitivity and selectivity.