▎ 摘　　要

NOVELTY - Preparing a graphene film involves subjecting the substrate to physical impurity removal and chemical impurity removal in sequence, and then placing the impurity-removed substrate in a chemical vapor deposition (CVD) system and performing annealing treatment. The annealed substrate is placing in an inert atmosphere, introducing a gaseous carbon source and hydrogen to perform graphene growth, where the flow rate of the carbon source is 1-10 sccm, and the flow ratio of the carbon source to the hydrogen gas is 1:5-100 to obtain the desired product. USE - Method for preparing a graphene film used for a display screen, an electronic device, and a microelectromechanical sensor (claimed). ADVANTAGE - The method enables to prepare a graphene film, which has high-quality single-layer or small-layer graphene film, and fast growth rate of graphene film, and greatly reduces production cost, and has promoted the wide application of graphene in the fields of display screens, electronic devices and microelectromechanical sensors.