Origin of layer decoupling in ordered multilayer graphene grown by high-temperature sublimation on C-face 4H-SiC

Ingemar Persson, Nerijus Armakavicius, Chamseddine Bouhafs, Vallery Stanishev, Philipp Kühne, Tino Hofmann, Mathias Schubert, Johanna Rosen, Rositsa Yakimova, Per O.Å. Persson, Vanya Darakchieva

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Abstract

We study the origin of layer decoupling in ordered multilayer graphene grown by high temperature sublimation on C-face 4H-SiC. The mid-infrared optical Hall effect technique is used to determine the magnetic field dependence of the inter-Landau level transition energies and their optical polarization selection rules, which unambiguously show that the multilayer graphene consists of electronically decoupled layers. Transmission electron microscopy reveals no out-of-plane rotational disorder between layers in the stack, which is in contrast to what is typically observed for C-face graphene grown by low temperature sublimation. It is found that the multilayer graphene maintains AB-stacking order with increased interlayer spacing by 2.4%-8.4% as compared to highly oriented pyrolytic graphite. Electron energy loss spectroscopy mapping reveals Si atoms trapped in between layers, which are proposed to be the cause for the observed increased interlayer spacing leading to layer decoupling. Based on our results, we propose a defect-driven growth evolution mechanism for multilayer graphene on C-face SiC via high temperature sublimation.

Original languageEnglish (US)
Article number011104
JournalAPL Materials
Volume8
Issue number1
DOIs
Publication statusPublished - Jan 1 2020

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ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)

Cite this

Persson, I., Armakavicius, N., Bouhafs, C., Stanishev, V., Kühne, P., Hofmann, T., ... Darakchieva, V. (2020). Origin of layer decoupling in ordered multilayer graphene grown by high-temperature sublimation on C-face 4H-SiC. APL Materials, 8(1), [011104]. https://doi.org/10.1063/1.5134862