Enhanced Performance in Epitaxial Graphene FETs with Optimized Channel Morphology

Abstract

This letter reports the impact of surface morphology on the carrier transport and RF performance of graphene FETs formed on epitaxial graphene films synthesized on SiC substrates. Such graphene exhibits long terrace structures with widths between 3-5 μm and steps of 10\pm2 nm in height. While a carrier mobility above 3000 cm2/Vs at a carrier density of 1e12 cm-2 is obtained in a single graphene terrace domain at room temperature, the step edges can result in a vicinal step resistance of ~21 kΩ.μm. By orienting the transistor layout so that the entire channel lies within a single graphene terrace, and reducing the access resistance associated with the ungated part of the channel, a cut-off frequency above 200 GHz is achieved for graphene FETs with channel lengths of 210 nm, which is the highest value reported on epitaxial graphene thus far.

References in corpus (2)

• Ultrahigh electron mobility in suspended graphene
• Wafer-scale Epitaxial Graphene Growth on the Si-face of Hexagonal SiC (0001) for High Frequency Transistors

Cited by in corpus (7)

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• Static Non-linearity in Graphene Field Effect Transistors
• Modeling of graphene Hall effect sensors for microbead detection
• Physical Properties of Zener Tunnelling Nano-devices in Graphene