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arXiv · 0908.3822

Observation of quantum-Hall effect in gated epitaxial graphene grown on SiC (0001)

T. Shen·J. J. Gu·M. Xu·Y. Q. Wu·M. L. Bolen·M. A. Capano·L. W. Engel·P. D. Ye
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Abstract

Epitaxial graphene films were formed on the Si-face of semi-insulating 4H-SiC substrates by a high temperature sublimation process. A high-k gate stack on epitaxial graphene is realized by inserting a fully oxidized nanometer thin aluminum film as a seeding layer followed by an atomic-layer deposition process. The electrical properties of epitaxial graphene films are sustained after gate stack formation without significant degradation. At low temperatures, the quantum-Hall effect in Hall resistance is observed along with pronounced Shubnikov-de Hass oscillations in diagonal magneto-resistance of gated epitaxial graphene on SiC (0001).

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T. Shen, J. J. Gu, M. Xu, Y. Q. Wu, M. L. Bolen, M. A. Capano, L. W. Engel, P. D. Ye. 2009-10-29. Observation of quantum-Hall effect in gated epitaxial graphene grown on SiC (0001). https://doi.org/10.1063/1.3254329

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