Silicon nitride gate dielectrics and band gap engineering in graphene layers.
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.
Zhu
Wenjuan
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IBM Thomas J Watson Research Center, Yorktown Heights, New York 10598, USA. wenjuan@us.ibm.com
Neumayer
Deborah
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Perebeinos
Vasili
V
Avouris
Phaedon
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