%0 Journal Article
%T Dependence of the Raman spectrum characteristics on the number of layers and stacking orientation in few-layer graphene
%+ Laboratoire Charles Coulomb (L2C)
%+ Department of Physics and Research Group on Carbon Nanostructures (CARBONNAGe)
%A Bayle, Maxime
%A Reckinger, Nicolas
%A Huntzinger, Jean-Roch
%A Felten, Alexandre
%A Bakaraki, Ahmad
%A Landois, Perine
%A Colomer, Jean-Francois
%A Henrard, Luc
%A Zahab, Ahmed-Azmi
%A Sauvajol, Jean-Louis
%A Paillet, Matthieu
%< avec comité de lecture
%Z L2C:15-234
%@ 0370-1972
%J physica status solidi (b)
%I Wiley
%V 252
%N 11
%P 2375-2379
%8 2015-11
%D 2015
%R 10.1002/pssb.201552204
%K 2D band
%K few-layer graphene
%K graphene
%K optical contrast
%K Raman spectroscopy
%Z Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]Journal articles
%X Few-layer graphene (FLG) samples prepared by two methods (chemical vapour deposition on copper followed by transfer onto SiO2/Si substrate and mechanical exfoli-ation) are characterised by combined optical contrast and micro-Raman mapping experiments. We examine the be-haviour of the integrated intensity ratio of the 2D and G bands (A2D/AG) and of the 2D band width (2D) as a function of the number of layers (N). For our mechanically exfoliated FLG, A2D/AG decreases and 2D increases with N as expected for commensurately stacked FLG. For CVD grown FLG (2 to 6 layers), both similar and opposite behaviours are observed and are ascribed to dif-ferent stacking orders. For small (resp. large) relative ro-tation angle between adjacent layers (), the values of the A2D/AG ratio is smaller (resp. larger) and the 2D band is broader (resp. narrower) than for single layer graphene. Moreover, the A2D/AG ratio decreases (resp. increases) and, conversely, 2D increases (resp. decreases) as a function of N for small (resp. large) . An intermediate behaviour has also been found and is interpreted as the presence of both small and large  within the studied area. In terms of characterisation criteria, these results confirm that neither A2D/AG nor 2D are definitive criteria to iden-tify single layer graphene, or to count the number of layers in FLG.
%G English
%L hal-01251716
%U https://hal.science/hal-01251716
%~ CNRS
%~ L2C
%~ MIPS
%~ UNIV-MONTPELLIER
%~ UM-2015-2021