▎ 摘　　要

NOVELTY - The photodetector has a source insulation layer (120) formed on a semiconductor substrate (100). A source electrode (130) is formed on the source insulation layer. A drain electrode (140) is formed on the substrate opposed to the source insulation layer or the source electrode. A graphene channel (110) is formed on the substrate and interposed between the source insulation layer and the source electrode. A gate insulation layer (150) is formed on the channel, and comprises light transmittance. A gate electrode (160) is formed on the gate insulation layer, and comprises light transmittance. USE - Graphene photodetector. ADVANTAGE - The photodetector adjusts a gain according to gate voltage applied and provides a high sensitivity. The photodetector allows electron-hole pairs formed in semiconductors and graphene, so that a photoabsorption rate and a photoreactivity of the photodetector are increased, and the photoelectric conversion gain is increased or decreased in response to the gate voltage. The photodetector improves photoreactivity or controls photoreactivity. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a graphene photodetector. Semiconductor substrate (100) Graphene channel (110) Source insulation layer (120) Source electrode (130) Drain electrode (140) Gate insulation layer (150) Gate electrode (160)