Figure 6. Characterization of the graphene/Si Schottky junctions analyzed by SKPM and CAFM. a) Topographical image of the graphene/Si surface in SKPM mode. b-c) Mapping the distribution of the surface potential in the presence (“light”) and absence (“dark”) of light irradiation, respectively. d) The band change between graphene and Si is illustrated. e) Topographical image of the graphene/Si surface in CAFM mode. f-g) Mapping the distribution of the surface current in the presence (“light”) and absence (“dark”) of light illumination, respectively. h) The current values correspond to the white dotted lines in Figures 3f-3g. i-k) Images correspond to current maps collected using various biases and light states, as indicated on each image. l) TypicalI  – V curve obtained by sweeping the bias applied to the graphene/Si Schottky junctions between –3 and + 4 V in the dark (Average value measured under the 10  ×  10 µm2 area).