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arXiv · 1807.04772

Ultra Low Specific Contact Resistivity in Metal-Graphene Junctions via Atomic Orbital Engineering

Vikram Passi·Amit Gahoi·Enrique G. Marin·Teresa Cusati·Alessandro Fortunelli·Giuseppe Iannaccone·Gianluca Fiori·Max C. Lemme
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Abstract

A systematic investigation of graphene edge contacts is provided. Intentionally patterning monolayer graphene at the contact region creates well-defined edge contacts that lead to a 67% enhancement in current injection from a gold contact. Specific contact resistivity is reduced from 1372 Ωm for a device with surface contacts to 456 Ωm when contacts are patterned with holes. Electrostatic doping of the graphene further reduces contact resistivity from 519 Ωm to 45 Ωm, a substantial decrease of 91%. The experimental results are supported and understood via a multi-scale numerical model, based on density-functional-theory calculations and transport simulations. The data is analyzed with regards to the edge perimeter and hole-to-graphene ratio, which provides insights into optimized contact geometries. The current work thus indicates a reliable and reproducible approach for fabricating low resistance contacts in graphene devices. We provide a simple guideline for contact design that can be exploited to guide graphene and 2D material contact engineering.

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Vikram Passi, Amit Gahoi, Enrique G. Marin, Teresa Cusati, Alessandro Fortunelli, Giuseppe Iannaccone, Gianluca Fiori, Max C. Lemme. 2018-07-12. Ultra Low Specific Contact Resistivity in Metal-Graphene Junctions via Atomic Orbital Engineering. https://doi.org/10.1002/admi.201801285

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