Enhancing Graphene Sensor Performance: Investigating Substrate-Depedent Ion Detection
Journal
2025 IEEE BioSensors Conference, BioSensors 2025 - Conferece Proceedings
Start Page
1
End Page
4
ISBN (of the container)
979-833152000-7
Date Issued
2025-11-18
Author(s)
Abstract
Graphene field-effect transistors (GFETs) show great potential for biosensor due to their exceptional sensitivity to surface charge. However, their sensing performance is highly sensitive to external environmental conditions and strongly influenced by interfacial effects. This study investigates the impact of different supporting layers- SiO2, PMMA, and PTFE - on the performance of GFETs in ionic solutions with different concentrations and ionic valencies. Electrical measurements reveal that OS-GFET exhibits significant charge trapping, leading to charge neutrality point shifts. In contrast, OPMS-GFET and OPTS-GFET demonstrate lower charge trapping due to surface functionalization. This effect is more significant for divalent ions (Mg2) than for monovalent ions (K). These findings underscore the importance of interfacial modifications in enhancing the sensitivity of GFET-based biosensors for real-time ion detection and biochemical applications.
Event(s)
3rd Annual IEEE BioSensors Conference, BioSensors 2025
Subjects
biosensor
charge neutrality point
Graphene field-effect transistor (GFET)
interfacial engineering
ion sensing
Publisher
IEEE
Type
conference paper