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arXiv · 0802.4103

Top-gated graphene field-effect-transistors formed by decomposition of SiC

Y. Q. Wu·P. D. Ye·M. A. Capano·Y. Xuan·Y. Sui·M. Qi·J. A. Cooper
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Abstract

Top-gated, few-layer graphene field-effect transistors (FETs) fabricated on thermally-decomposed semi-insulating 4H-SiC substrates are demonstrated. Physical vapor deposited SiO2 is used as the gate dielectric. A two-dimensional hexagonal arrangement of carbon atoms with the correct lattice vectors, observed by high-resolution scanning tunneling microscopy, confirms the formation of multiple graphene layers on top of the SiC substrates. The observation of n-type and p-type transition further verifies Dirac Fermions unique transport properties in graphene layers. The measured electron and hole mobility on these fabricated graphene FETs are as high as 5400 cm2/Vs and 4400 cm2/Vs respectively, which are much larger than the corresponding values from conventional SiC or silicon.

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Y. Q. Wu, P. D. Ye, M. A. Capano, Y. Xuan, Y. Sui, M. Qi, J. A. Cooper. 2008-02-27. Top-gated graphene field-effect-transistors formed by decomposition of SiC. https://doi.org/10.1063/1.2889959

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