▎ 摘　　要

NOVELTY - The process comprises: electrochemical polishing a copper substrate for 0.5-10 minutes; washing the substrate using deionized water; further washing using ethanol for 0.1-10 minutes and then drying on a quartz tube; performing chemical vapor deposition on the substrate in a special growth chamber; growing graphene films on the substrate in a heating furnace at high temperature; and filling high purity hydrogen into the chamber at a flow rate of 5-500 standard cubic centimeters per minute (sccm), a pressure of 5-500 Pa and a temperature of 850-1075 degrees C. USE - The process is useful for preparing a multi-graphene film (claimed). ADVANTAGE - The process is capable of simply and rapidly preparing the multi-graphene film with high uniformity. DETAILED DESCRIPTION - The process comprises: electrochemical polishing a copper substrate for 0.5-10 minutes; washing the substrate using deionized water; further washing using ethanol for 0.1-10 minutes and then drying on a quartz tube; performing chemical vapor deposition on the substrate in a special growth chamber; growing graphene films on the substrate in a heating furnace at high temperature; filling high purity hydrogen into the chamber at a flow rate of 5-500 standard cubic centimeters per minute (sccm), a pressure of 5-500 Pa and a temperature of 850-1075 degrees C; further filling high purity methane into the chamber at a flow rate of 5-500 sccm, a pressure of 10-1500 Pa and a temperature of 850-1075 degrees C; opening a lid of the chamber for rapid cooling to grow multilayer graphene films; and introducing argon gas in the chamber at less than 50 degrees C. The quartz tube has a diameter of 5 mm.