▎ 摘　　要

NOVELTY - Preparing metal/graphene/polycrystalline diamond film particle detector comprises depositing a layer of graphene on the surface of the patterned metal substrate as an ohmic contact electrode layer, and growing a diamond film in situ on the graphene, where the thickness of the metal base is 0.025-0.05 mm, and the thickness of the diamond film is 0.25-0.5 mm. The metal substrate is copper foil or nickel foil. The copper foil is polycrystalline copper foil or nickel foil. The graphene is multilayer graphene. USE - The metal/graphene/polycrystalline diamond film particle detector is useful in field of nuclear physics. ADVANTAGE - The method includes steps preferably completed in the same set of microwave plasma chemical vapor deposition equipment, and the overall structure of the detector is constructed by in-situ continuous growth in the same set of equipment, materials does not need to be transferred between different devices, has high preparation efficiency, simple steps, low cost, and can ensure the high quality of each layer of material preparation.