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We present a semi-analytical model incorporating the effects of edge bond relaxation, the third nearest neighbor interactions, and edge scattering in graphene nanoribbon field-effect transistors (GNRFETs) with armchair-edge GNR (AGNR) channels. Unlike carbon nanotubes (CNTs) which do not have edges, the existence of edges in the AGNRs has a significant effect on the quantum capacitance and ballistic IV characteristics of GNRFETs. For an AGNR with an index of m=3p, the band gap decreases and the ON current increases whereas for an AGNR with an index of m=3p+1, the quantum capacitance increases and the ON current decreases. The effect of edge scattering, which reduces the ON current, is also included in the model.


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Computational Model of Edge Effects in Graphene Nanoribbon Transistors

Show Author's information Pei Zhao1Mihir Choudhury2Kartik Mohanram2Jing Guo1( )
Department of Electrical and Computer EngineeringUniversity of FloridaGainesvilleFL32611USA
Department of Electrical and Computer EngineeringRice UniversityHoustonTX77005USA

Abstract

We present a semi-analytical model incorporating the effects of edge bond relaxation, the third nearest neighbor interactions, and edge scattering in graphene nanoribbon field-effect transistors (GNRFETs) with armchair-edge GNR (AGNR) channels. Unlike carbon nanotubes (CNTs) which do not have edges, the existence of edges in the AGNRs has a significant effect on the quantum capacitance and ballistic IV characteristics of GNRFETs. For an AGNR with an index of m=3p, the band gap decreases and the ON current increases whereas for an AGNR with an index of m=3p+1, the quantum capacitance increases and the ON current decreases. The effect of edge scattering, which reduces the ON current, is also included in the model.

Keywords: Graphene nanoribbon field-effect transistor, edge bond relaxation, third nearest neighbor interaction, edge scattering

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DOI
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Publication history

Received: 16 August 2008
Revised: 13 September 2008
Accepted: 14 September 2008
Published: 01 October 2008
Issue date: October 2008

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© Tsinghua Press and Springer-Verlag 2008

Acknowledgements

Acknowledgements

The authors would like to thank Drs. C. T. White and D. Gunlycke for helpful discussions. This work was supported in part by the Office of Naval Research grant N000140810861, and in part by NSF grants ECCS-0824157 and CCF-0701547.

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