Step edge influence on barrier height and contact area in vertical heterojunctions between epitaxial graphene and n-type 4H-SiC

Journal Article · Mon Feb 17 00:00:00 EST 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4866024· OSTI ID:22283294

Nyakiti, L. O.; Robinson, Z. ^[1]; Anderson, T. J.; Myers-Ward, R. L.; Wheeler, V. D.; Eddy, C. R.; Gaskill, D. K.; Koehler, A. D.; Hobart, K. D.; Kub, F. J. ^[2]

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1. American Society for Engineering Education, Washington, DC 20036 (United States)
2. U.S. Naval Research Laboratory, 4555 Overlook Ave, SW, Washington, DC 20375 (United States)

Vertical rectifying contacts of epitaxial graphene grown by Si sublimation on the Si-face of 4H-SiC epilayers were investigated. Forward bias preferential conduction through the step edges was correlated by linear current density normalization. This phenomenon was observed on samples with 2.7–5.8 monolayers of epitaxial graphene as determined by X-ray photoelectron spectroscopy. A modified Richardson plot was implemented to extract the barrier height (0.81 eV at 290 K, 0.99 eV at 30 K) and the electrically dominant SiC step length of a Ti/Al contact overlapping a known region of approximately 0.52 μm wide SiC terraces.

• OSTI ID: 22283294
• Journal Information: Applied Physics Letters, Vol. 104, Issue 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
CURRENT DENSITY
EPITAXY
GRAPHENE
HETEROJUNCTIONS
N-TYPE CONDUCTORS
SILICON
SILICON CARBIDES
SUBLIMATION
TEMPERATURE DEPENDENCE
X-RAY PHOTOELECTRON SPECTROSCOPY