Characterization and physical modeling of MOS capacitors in epitaxial graphene monolayers and bilayers on 6H-SiC
Journal article, 2016

Capacitance voltage (CV) measurements are performed on planar MOS capacitors with an Al2O3 dielectric fabricated in hydrogen intercalated monolayer and bilayer graphene grown on 6H-SiC as a function of frequency and temperature. Quantitative models of the CV data are presented in conjunction with the measurements in order to facilitate a physical understanding of graphene MOS systems. An interface state density of order 2 . 10(12)eV(-1)cm(-2) is found in both material systems. Surface potential fluctuations of order 80-90meV are also assessed in the context of measured data. In bilayer material, a narrow bandgap of 260meV is observed consequent to the spontaneous polarization in the substrate. Supporting measurements of material anisotropy and temperature dependent hysteresis are also presented in the context of the CV data and provide valuable insight into measured and modeled data. The methods outlined in this work should be applicable to most graphene MOS systems.

Author

Michael Winters

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

E. O. Sveinbjornsson

Linköping University

University of Iceland

C. Melios

National Physical Laboratory (NPL)

University of Surrey

O. Kazakova

National Physical Laboratory (NPL)

W. Strupinski

Instytutu Technologii Materialow Elektronicznych w Warszawie

Niklas Rorsman

Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics

AIP Advances

2158-3226 (ISSN)

Vol. 6 8 085010

Graphene-Based Revolutions in ICT And Beyond (Graphene Flagship)

European Commission (FP7), 2013-10-01 -- 2016-03-31.

Subject Categories

Physical Sciences

DOI

10.1063/1.4961361

More information

Latest update

5/29/2018