Charge-density depinning at metal contacts of graphene field-effect transistors

Ryo Nouchi; Katsumi Tanigaki

doi:10.1063/1.3456383

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arXiv · 1003.3284

Charge-density depinning at metal contacts of graphene field-effect transistors

Ryo Nouchi·Katsumi Tanigaki

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Abstract

An anomalous distortion is often observed in the transfer characteristics of graphene field-effect transistors. We fabricate graphene transistors with ferromagnetic metal electrodes, which reproducibly display distorted transfer characteristics, and show that the distortion is caused by metal-graphene contacts with no charge-density pinning effect. The pinning effect, where the gate voltage cannot tune the charge density of graphene at the metal electrodes, has been experimentally observed; however, a pinning-free interface is achieved with easily-oxidizable metals. The distortion should be a serious problem for flexible electronic devices with graphene.

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Ryo Nouchi, Katsumi Tanigaki. 2010-06-15. Charge-density depinning at metal contacts of graphene field-effect transistors. https://doi.org/10.1063/1.3456383

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