Investigation of graphene-SiC interface by nanoscale electrical characterization

We have carried out an investigation of graphene/4H-SiC (0001) interface by nanoscale current transport measurements. Graphene was deposited by mechanical exfoliation of HOPG. Novel Scanning Probe Current Mapping and Scanning Probe Current Spectroscopy are found to be useful for non-destructive characterization of graphene. Presence of graphene lowers Schottky barrier height on 4H-SiC (0001). Observed barrier heights (0.8 +/- 0.1 eV) are comparable but higher than reported in literature for 6H-SiC (0001).