We studied variations in the Raman spectrum as a function of thenumber of graphene layers by using micro-Raman spectroscopy andatomic force microscopy (AFM). The sample preparation was done bymicromechanical cleaving of natural graphite on an $sim$300 nmSiO$_{2}$ layer. The Raman $G$ band ($sim$1580 cm$^{-1})$, $G^*$band ($sim$2450 cm$^{-1})$ and 2$D$ band ($sim$2700 cm$^{-1})$varied as functions of the number of graphene layers. The Raman 2$D$band was especially sensitive to the number of graphene layers.These features are related to the electronic band structure ofgraphene. Moreover, areas of different numbers of graphene layerswere clearly identified using spatially-resolved micro-Raman imagingspectroscopy.

Keywords: Graphene, Raman, AFM