We use cookies to ensure that we give you the best experience on our website. By continuing to browse this repository, you give consent for essential cookies to be used. You can read more about our Privacy and Cookie Policy.

Durham Research Online
You are in:

Dirac point and transconductance of top-gated graphene field-effect transistors operating at elevated temperature.

Hopf, T. and Vassilevski, K.V. and Escobedo-Cousin, E. and King, P.J. and Wright, N.G. and O'Neill, A.G. and Horsfall, A.B. and Goss, J.P. and Wells, G.H. and Hunt, M.R.C (2014) 'Dirac point and transconductance of top-gated graphene field-effect transistors operating at elevated temperature.', Journal of applied physics., 116 (15). p. 154504.


Top-gated graphene field-effect transistors (GFETs) have been fabricated using bilayer epitaxial graphene grown on the Si-face of 4H-SiC substrates by thermal decomposition of silicon carbide in high vacuum. Graphene films were characterized by Raman spectroscopy, Atomic Force Microscopy, Scanning Tunnelling Microscopy, and Hall measurements to estimate graphene thickness, morphology, and charge transport properties. A 27 nm thick Al2O3 gate dielectric was grown by atomic layer deposition with an e-beam evaporated Al seed layer. Electrical characterization of the GFETs has been performed at operating temperatures up to 100 °C limited by deterioration of the gate dielectric performance at higher temperatures. Devices displayed stable operation with the gate oxide dielectric strength exceeding 4.5 MV/cm at 100 °C. Significant shifting of the charge neutrality point and an increase of the peak transconductance were observed in the GFETs as the operating temperature was elevated from room temperature to 100 °C.

Item Type:Article
Full text:(VoR) Version of Record
Download PDF
Publisher Web site:
Publisher statement:© 2014 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics 116, 154504 (2014) and may be found at
Date accepted:06 October 2014
Date deposited:12 November 2014
Date of first online publication:17 October 2014
Date first made open access:No date available

Save or Share this output

Look up in GoogleScholar