Figure 5. Photodetector
constructed with the monolayer
graphene directly synthesized on Si substrate. a) Schematic diagram of
the photodetector. b) I-V characteristics of the graphene/Si-based
photodetectors measured in the dark and under light illumination with
variable wavelengths of 532, 980, and 1550 nm, respectively. The laser
intensity is set at 30 mW/cm2.