Fig. 3: Characterization of graphene in the μGS.

a Graphene sheet thickness measured by atomic force microscopy. b Unique spectral peaks of graphene observed using Raman spectroscopy. c Current-gate voltage response in a characteristic device showing the change in carrier mobility before and after passivation. The Dirac point shifts due to the change in surface interactions of the μGS. The inset compares mobility before and after passivation to that of silicon sensors