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arXiv · 0909.0020

Tuning the graphene work function by electric field effect

Young-Jun Yu·Yue Zhao·Sunmin Ryu·Louis E. Brus·Kwang S. Kim·Philip Kim
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Abstract

We report variation of the work function for single and bi-layer graphene devices measured by scanning Kelvin probe microscopy (SKPM). Using the electric field effect, the work function of graphene can be adjusted as the gate voltage tunes the Fermi level across the charge neutrality point. Upon biasing the device, the surface potential map obtained by SKPM provides a reliable way to measure the contact resistance of individual electrodes contacting graphene.

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Young-Jun Yu, Yue Zhao, Sunmin Ryu, Louis E. Brus, Kwang S. Kim, Philip Kim. 2009-08-31. Tuning the graphene work function by electric field effect. https://doi.org/10.1021/nl901572a

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