▎ 摘　　要

NOVELTY - A silicon-graphene based photodetector preparing method involves providing an silicon on insulator substrate, where the silicon on insulator substrate comprises bulk silicon substrate, insulating layer, and top layer silicon, and etching the first openings and the second openings spaced apart in the top silicon, forming a first metal electrode in the first opening and a portion of the top silicon, forming a second metal electrode in the second opening, forming a graphene layer formed on the top layer silicon and connected to the second metal electrode across the gap, forming a fixed layer on the surface of the structure, removing the bulk silicon substrate and the insulating layer to expose the top silicon, the first metal electrode, and the second metal electrode. USE - Method for preparing silicon-graphene based photodetector. ADVANTAGE - The method enables preparing silicon-graphene based photodetector with high flexibility, and in simple and cost effective manner.