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arXiv · 1603.04872

Thermo Activated Hysteresis on High Quality Graphene/h-BN Devices

Abstract

We report on gate hysteresis in resistance on high quality graphene/h-BN devices. We observe a thermal activated hysteretic behavior in resistance as a function of the applied gate voltage at temperatures above 375K. In order to investigate the origin of the hysteretic phenomenon, we design heterostructures involving graphene/h-BN devices with different underlying substrates such as: SiO2/Si and graphite; where heavily doped silicon and graphite are used as a back gate electrodes, respectively. The gate hysteretic behavior of the resistance shows to be present only in devices with an h-BN/SiO2 interface and is dependent on the orientation of the applied gate electric field and sweep rate. Finally, we suggest a phenomenological model, which captures all of our findings based on charges trapped at the h-BN/SiO2. Certainly, such hysteretic behavior in graphene resistance represents a technological problem for the application of graphene devices at high temperatures, but conversely, it can open new routes for applications on digital electronics and graphene memory devices.

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BibTeXRIS

A. R. Cadore, E. Mania, K. Watanabe, T. Taniguchi, R. G. Lacerda, L. C. Campos. 2016-03-15. Thermo Activated Hysteresis on High Quality Graphene/h-BN Devices. https://doi.org/10.1063/1.4953162

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