The effect of substrates on the Raman spectrum of graphene: Graphene-on-sapphire and graphene-on-glass

The authors investigated the influence of substrates on Raman scattering spectrum from graphene. The room-temperature Raman signatures from graphene layers on GaAs, sapphire, and glass substrates were compared with those from graphene on the standard Si/SiO2 (300 nm) substrate, which served as a reference. It was found that while G peak of graphene on Si/SiO2 and GaAs is positioned at 1580 cm(-1), it is downshifted by similar to 5 cm(-1) for graphene on sapphire and, in some cases, splits into doublets for graphene on glass with the central frequency around 1580 cm(-1). The obtained results are important for nanometrology of graphene and graphene-based devices. (c) 2007 American Institute of Physics.