Comparative characterization of graphene grown by chemical vapor deposition, transferred to nonconductive substrate, and subjected to Ar ion bombardment using X-ray photoelectron and Raman spectroscopies

Abstract

Graphene specimens grown by chemical vapor deposition on copper and graphene transferred to Si/SiO2 substrate were subjected to an Ar+ ion treatment. A combination of X-ray photoelectron spectroscopy and Raman spectroscopy was used for the characterization graphene in as-grown, air exposed, transferred to Si/SiO2, and subjected to Ar+ bombardment states. We paid attention to make the analysis of the same spot of the sample. It is shown, that the bombardment of graphene on Cu substrate leads to edge etching and decrease of graphene crystallites size. The samples on Si/SiO2 appear less susceptible to etching, however, the defect concentrations reach up the value two orders of magnitude higher than that in graphene on Cu. It is explained by an interaction of carbon on the defect sites introduced under the bombardment with carbon-oxygen radicals generated due to decomposition of organic groups adsorbed on graphene surface.