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.
@article{arxiv.0802.4103,
title = {Top-gated graphene field-effect-transistors formed by decomposition of SiC},
author = {Y. Q. Wu and P. D. Ye and M. A. Capano and Y. Xuan and Y. Sui and M. Qi and J. A. Cooper},
journal= {arXiv preprint arXiv:0802.4103},
year = {2009}
}