Graphene Based Flexible Hall Sensors

İnkaya, Uğur Yiğit
Graphene is a two-dimensional material that has electronic properties such as having low density of charge carriers with high mobility, which are ideal for fabricating Hall sensors. Also considering its elastic properties, it is a promising material for flexible electronics including flexible Hall sensorics. Graphene was synthesized via atmospheric pressure chemical vapor deposition (CVD) on 20μm-thick copper by using methane as carbon feedstock. CVD-graphene was transferred onto EVA-coated PET film via lamination. By using the resultant graphene/EVA/PET laminate, we manufactured Hall devices. We characterized the devices by measuring their Hall sensitivity. The devices showed mostly linear sensor response with sensitivity of up to 1200 Ω/T. Also we studied graphene-based multilayered conductive films on EVA/PET by using Hall devices for the electronic characterization. The films were made via layer-by-layer transfer-printing graphene onto EVA/PET. Further characterization was performed by van der Pauw measurements. It revealed mobilities around 1000 cm2/(Vs) and the hole density increasing almost linearly with the number of laminations performed to make the film. The surface topography of the films were studied via atomic force microscopy. Finally we performed Joule heating experiments that showed the surface temperature of the film can be increased up to ~100°C.


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Citation Formats
U. Y. İnkaya, “Graphene Based Flexible Hall Sensors,” Ph.D. - Doctoral Program, Middle East Technical University, 2021.