Ultra-sensitive Hall sensors based on graphene encapsulated in hexagonal boron nitride

TL;DR

This paper reports the development of ultra-sensitive graphene-based Hall sensors encapsulated in hexagonal boron nitride, demonstrating superior sensitivity and low noise performance suitable for industrial applications.

Contribution

The paper introduces a novel fabrication of graphene boron nitride heterostructure Hall sensors with record sensitivity and low noise, advancing sensor technology.

Findings

Sensitivity up to 5700 V/AT and 3 V/VT

Magnetic resolution below 50 nT/Hz

High device quality with low charge carrier density

Abstract

The encapsulation of graphene in hexagonal boron nitride provides graphene on substrate with excellent material quality. Here, we present the fabrication and characterization of Hall sensor elements based on graphene boron nitride heterostructures, where we gain from high mobility and low charge charier density at room temperature. We show a detailed device characterization including Hall effect measurements under vacuum and ambient conditions. We achieve a current- and voltage-related sensitivity of up to 5700 V/AT and 3 V/VT, respectively, outpacing state-of- the-art silicon and III/V Hall sensor devices. Finally, we extract a magnetic resolution limited by low frequency electric noise of less than 50 nT/pHz making our graphene sensors highly interesting for industrial applications.