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arXiv · 1508.00805

Graphene field effect transistors with Niobium contacts and asymmetric transfer characteristics

Antonio Di Bartolomeo·Filippo Giubileo·Francesco Romeo·Paolo Sabatino·Giovanni Carapella·Laura Iemmo·Thomas Schroeder·Grzegorz Lupina
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Abstract

We fabricate back-gated field effect transistors using Niobium electrodes on mechanically exfoliated monolayer graphene and perform electrical characterization in the pressure range from atmospheric down to 10-4 mbar. We study the effect of room temperature vacuum degassing and report asymmetric transfer characteristics with a resistance plateau in the n-branch. We show that weakly chemisorbed Nb acts as p-dopant on graphene and explain the transistor characteristics by Nb/graphene interaction with unpinned Fermi level at the interface.

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Antonio Di Bartolomeo, Filippo Giubileo, Francesco Romeo, Paolo Sabatino, Giovanni Carapella, Laura Iemmo, Thomas Schroeder, Grzegorz Lupina. 2015-08-04. Graphene field effect transistors with Niobium contacts and asymmetric transfer characteristics. https://doi.org/10.1088/0957-4484%2F26%2F47%2F475202

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