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Updated: Jul 4, 2026

Analysis of Contact Interfaces for Single GaN Nanowire Devices
Published on: November 15, 2013
Contact effects in graphene nanoribbon transistors
Gengchiau Liang1, Neophytos Neophytou, Mark S Lundstrom
1Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576. elelg@nus.edu.sg
Abstract:
The effects of the various contact types and shapes on the performance of Schottky barrier graphene nanoribbon field-effect-transistors (GNRFETs) have been investigated using a real-space quantum transport simulator based on the NEGF approach self-consistently coupled to a three-dimensional Poisson solver for treating the electrostatics. The device channel considered is a double gate semiconducting armchair nanoribbon. The types of contacts considered are (a) a semi-infinite normal metal, (b) a semi-infinite graphene sheet, (c) finite size rectangular shape armchair graphene contacts, (d) finite size wedge shape graphene contacts, and (e) zigzag graphene nanoribbon contacts. Among these different contact types, the semi-infinite graphene sheet contacts show the worst performance because of their very low density of states around the Dirac point resulting in low transmission possibility through the Schottky barrier, both at ON and OFF states. Although all other types of contacts can have significant enhancement in I ON to I OFF ratio, the zigzag GNR contacts show promising and size invariant performance due to the metallic properties.
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