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Title: Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001)

Abstract

Structural and electronic properties of epitaxial graphene on 4H-SiC were studied before and after an atomic oxidation process. X-ray photoemission spectroscopy indicates that oxygen penetrates into the substrate and decouples a part of the interface layer. Raman spectroscopy demonstrates the increase of defects due to the presence of oxygen. Interestingly, we observed on the near edge x-ray absorption fine structure spectra a splitting of the π* peak into two distinct resonances centered at 284.7 and 285.2 eV. This double structure smears out after the oxidation process and permits to probe the interface architecture between graphene and the substrate.

Authors:
 [1];  [2];  [1]; ;  [3]; ;  [4];  [2];  [5]
  1. Laboratoire de Photonique et de Nanostructures (CNRS-LPN), Route de Nozay, 91460 Marcoussis (France)
  2. (France)
  3. Synchrotron-SOLEIL, Saint-Aubin, BP48, F91192 Gif sur Yvette Cedex (France)
  4. CNRS, UMR 7588, Institut des NanoSciences de Paris (INSP), F-75005 Paris (France)
  5. Institut de Minéralogie et de Physique des Milieux Condensés, CNRS–UMR7590, Sorbonne Universités-Pierre et Marie Curie, 4 Pl. Jussieu, 75005 Paris (France)
Publication Date:
OSTI Identifier:
22283037
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 104; Journal Issue: 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION SPECTRA; CRYSTAL STRUCTURE; EPITAXY; FINE STRUCTURE; GRAPHENE; INTERFACES; LAYERS; OXIDATION; OXYGEN; PHOTOEMISSION; RAMAN SPECTRA; RAMAN SPECTROSCOPY; SILICON CARBIDES; SUBSTRATES; X-RAY SPECTRA

Citation Formats

Velez-Fort, E., Institut de Minéralogie et de Physique des Milieux Condensés, CNRS–UMR7590, Sorbonne Universités-Pierre et Marie Curie, 4 Pl. Jussieu, 75005 Paris, Ouerghi, A., Silly, M. G., Sirtti, F., Eddrief, M., Marangolo, M., Sorbonne Universités, UPMC Univ. Paris 06, UMR 7588, INSP, F-75005 Paris, and Shukla, A. Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001). United States: N. p., 2014. Web. doi:10.1063/1.4867348.
Velez-Fort, E., Institut de Minéralogie et de Physique des Milieux Condensés, CNRS–UMR7590, Sorbonne Universités-Pierre et Marie Curie, 4 Pl. Jussieu, 75005 Paris, Ouerghi, A., Silly, M. G., Sirtti, F., Eddrief, M., Marangolo, M., Sorbonne Universités, UPMC Univ. Paris 06, UMR 7588, INSP, F-75005 Paris, & Shukla, A. Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001). United States. doi:10.1063/1.4867348.
Velez-Fort, E., Institut de Minéralogie et de Physique des Milieux Condensés, CNRS–UMR7590, Sorbonne Universités-Pierre et Marie Curie, 4 Pl. Jussieu, 75005 Paris, Ouerghi, A., Silly, M. G., Sirtti, F., Eddrief, M., Marangolo, M., Sorbonne Universités, UPMC Univ. Paris 06, UMR 7588, INSP, F-75005 Paris, and Shukla, A. 2014. "Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001)". United States. doi:10.1063/1.4867348.
@article{osti_22283037,
title = {Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001)},
author = {Velez-Fort, E. and Institut de Minéralogie et de Physique des Milieux Condensés, CNRS–UMR7590, Sorbonne Universités-Pierre et Marie Curie, 4 Pl. Jussieu, 75005 Paris and Ouerghi, A. and Silly, M. G. and Sirtti, F. and Eddrief, M. and Marangolo, M. and Sorbonne Universités, UPMC Univ. Paris 06, UMR 7588, INSP, F-75005 Paris and Shukla, A.},
abstractNote = {Structural and electronic properties of epitaxial graphene on 4H-SiC were studied before and after an atomic oxidation process. X-ray photoemission spectroscopy indicates that oxygen penetrates into the substrate and decouples a part of the interface layer. Raman spectroscopy demonstrates the increase of defects due to the presence of oxygen. Interestingly, we observed on the near edge x-ray absorption fine structure spectra a splitting of the π* peak into two distinct resonances centered at 284.7 and 285.2 eV. This double structure smears out after the oxidation process and permits to probe the interface architecture between graphene and the substrate.},
doi = {10.1063/1.4867348},
journal = {Applied Physics Letters},
number = 9,
volume = 104,
place = {United States},
year = 2014,
month = 3
}
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