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Title: Short-range ordering of ion-implanted nitrogen atoms in SiC-graphene

We perform a structural analysis of nitrogen-doped graphene on SiC(0001) prepared by ultra low-energy ion bombardment. Using scanning tunneling microscopy, we show that nitrogen atoms are incorporated almost exclusively as graphitic substitution in the graphene honeycomb lattice. With an irradiation energy of 25 eV and a fluence of approximately 5 × 10{sup 14 }cm{sup −2}, we achieve a nitrogen content of around 1%. By quantitatively comparing the position of the N-atoms in the topography measurements with simulated random distributions, we find statistically significant short-range correlations. Consequently, we are able to show that the dopants arrange preferably at lattice sites given by the 6 × 6-reconstruction of the underlying substrate. This selective incorporation is most likely triggered by adsorbate layers present during the ion bombardment. This study identifies low-energy ion irradiation as a promising method for controlled doping in epitaxial graphene.
Authors:
; ;  [1] ; ; ;  [2] ; ;  [3]
  1. IV. Physikalisches Institut der Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen (Germany)
  2. II. Physikalisches Institut der Universität Göttingen, Friedrich-Hund-Platz 1, D-37077 Göttingen (Germany)
  3. Department of Condensed Matter Physics and Materials' Science, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400 005 (India)
Publication Date:
OSTI Identifier:
22303499
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 11; 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; CORRELATIONS; DISTRIBUTION; DOPED MATERIALS; EPITAXY; EV RANGE; GRAPHENE; GRAPHITE; ION IMPLANTATION; IRRADIATION; NITROGEN IONS; RANDOMNESS; SCANNING TUNNELING MICROSCOPY; SILICON CARBIDES; SIMULATION; SUBSTRATES; TOPOGRAPHY