Enhanced intrinsic voltage gain in artificially stacked bilayer CVD graphene field effect transistors

Himadri Pandey; Jorge Daniel Aguirre Morales; Satender Kataria; Sebastien Fregonese; Vikram Passi; Mario Iannazzo; Thomas Zimmer; Eduard Alarcon; Max C. Lemme

doi:10.1002/andp.201700106

arXiv · 2212.01877

Enhanced intrinsic voltage gain in artificially stacked bilayer CVD graphene field effect transistors

Himadri Pandey·Jorge Daniel Aguirre Morales·Satender Kataria·Sebastien Fregonese·Vikram Passi·Mario Iannazzo·Thomas Zimmer·Eduard Alarcon·Max C. Lemme

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Abstract

We report on electronic transport in dual-gate, artificially stacked bilayer graphene field effect transistors (BiGFETs) fabricated from large-area chemical vapor deposited (CVD) graphene. The devices show enhanced tendency to current saturation, which leads to reduced minimum output conductance values. This results in improved intrinsic voltage gain of the devices when compared to monolayer graphene FETs. We employ a physics based compact model originally developed for Bernal stacked bilayer graphene FETs (BSBGFETs) to explore the observed phenomenon. The improvement in current saturation may be attributed to increased charge carrier density in the channel and thus reduced saturation velocity due to carrier-carrier scattering.

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Himadri Pandey, Jorge Daniel Aguirre Morales, Satender Kataria, Sebastien Fregonese, Vikram Passi, Mario Iannazzo, Thomas Zimmer, Eduard Alarcon, Max C. Lemme. 2022-12-04. Enhanced intrinsic voltage gain in artificially stacked bilayer CVD graphene field effect transistors. https://doi.org/10.1002/andp.201700106

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