Flexible Hall Sensors Based on Graphene

TL;DR

This paper reports the development of highly sensitive, flexible graphene-based Hall sensors fabricated on Kapton foil, demonstrating durability under bending and outperforming previous flexible sensors in sensitivity.

Contribution

The work introduces a scalable fabrication process for flexible graphene Hall sensors with record sensitivities and excellent mechanical durability.

Findings

Sensitivity up to 0.096 V/VT and 79 V/AT achieved

Sensors maintain performance after bending to small radii

Durability confirmed over 1,000 bending cycles

Abstract

The excellent electronic and mechanical properties of graphene provide a perfect basis for high performance flexible electronic and sensor devices. Here, we present the fabrication and characterization of flexible graphene based Hall sensors. The Hall sensors are fabricated on 50 um thick flexible Kapton foil using large scale graphene grown by chemical vapor deposition technique on copper foil. Voltage and current normalized sensitivities of up to 0.096 V/VT and 79 V/AT were measured, respectively. These values are comparable to the sensitivity of rigid silicon based Hall sensors and are the highest values reported so far for any flexible Hall sensor devices. The sensitivity of the Hall sensor shows no degradation after being bent to a minimum radius of 4 mm, which corresponds to a tensile strain of 0.6%, and after 1,000 bending cycles to a radius of 5 mm.