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Updated: Jul 7, 2025

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
Subthreshold slope below 60 mV/decade in graphene transistors induced by channel geometry at the wafer-scale
Mircea Dragoman1, Adrian Dinescu1, Silviu Vulpe1
1National Research and Development Institute in Microtechnology, Str. Erou Iancu Nicolae 126A, 077190 Bucharest, Romania.
Abstract:
In this paper, we demonstrate experimentally that field-effect transistors with nanoconstricted graphene monolayer channels have a subthreshold swing (SS) below 60 mV/dec, which is slightly dependent on temperature. Two shapes of nanoconstricted graphene monolayers are considered: (i) a bow-tie shape, representative for a symmetric channel, and (ii) a trapezoidal shape, which illustrates an asymmetric channel. While both types of nonuniform channels are opening a bandgap in graphene, thus showing an on/off ratio of 105, the SS in the graphene bow-tie channel is below 60 mV/dec in the temperature range 25 °C-44 °C.
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