LAUSR

In this letter, a nondestructive local characterization of graphene fabricated by the reduction method on graphene oxide aqueous was demonstrated by using a near-field scanning microwave microscopy (NSMM). The dielectric properties of graphene films have been extracted to analyze the quality of graphene. Clear images of defects on graphene film were obtained by mapping the resonant frequency, $f_{r}$ , and quality factor, $Q$ , of a given area. The results and images obtained demonstrate that NSMM can be employed in thin-film analysis for characterization of local electrical properties of materials in a nondestructive manner and for obtaining a map of conductivity distribution.