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arXiv · 2003.08147

The performance limits of epigraphene Hall sensors

Hans He·Naveen Shetty·Thilo Bauch·Sergey Kubatkin·Timo Kaufmann·Martin Cornills·Rositsa Yakimova·Samuel Lara-Avila
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Abstract

Epitaxial graphene on silicon carbide, or epigraphene, provides an excellent platform for Hall sensing devices in terms of both high electrical quality and scalability. However, the challenge in controlling its carrier density has thus far prevented systematic studies of epigraphene Hall sensor performance. In this work we investigate epigraphene Hall sensors where epigraphene is doped across the Dirac point using molecular doping. Depending on the carrier density, molecular-doped epigraphene Hall sensors reach room temperature sensitivities $S_V=0.23 V/VT$,$S_I=1440 V/AT$ and magnetic field detection limits down to $B_{MIN}=27$ $nT/\sqrt{Hz}$ at 20 kHz. Thermally stabilized devices demonstrate operation up to $T=150$ $^oC$ with $S_V=0.12 V/VT$, $S_I=300 V/AT$ and $B_{MIN}\approx 100$ $nT/\sqrt{Hz}$ at 20 kHz.

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Hans He, Naveen Shetty, Thilo Bauch, Sergey Kubatkin, Timo Kaufmann, Martin Cornills, Rositsa Yakimova, Samuel Lara-Avila. 2020-03-18. The performance limits of epigraphene Hall sensors. https://doi.org/10.1063/5.0006749

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