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arXiv · 1009.2023

Silicon nitride gate dielectrics and bandgap engineering in graphene layers

Wenjuan Zhu·Deborah Neumayer·Vasili Perebeinos·Phaedon Avouris
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Abstract

We show that silicon nitride can provide uniform coverage of graphene in field-effect transistors while preserving the channel mobility. This insulator allowed us to study the maximum channel resistance at the Dirac (neutrality) point as a function of the strength of a perpendicular electric field in top-gated devices with different numbers of graphene layers. Using a simple model to account for surface potential variations (electron-hole puddles) near the Dirac point we estimate the field-induced band-gap or band-overlap in the different layers.

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Wenjuan Zhu, Deborah Neumayer, Vasili Perebeinos, Phaedon Avouris. 2010-09-10. Silicon nitride gate dielectrics and bandgap engineering in graphene layers. https://doi.org/10.1021/nl101832y

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