Process Optimization for Synthesis of High-Quality Graphene Films by Low-Pressure Chemical Vapor Deposition

Low-pressure chemical vapor deposition (LPCVD) is a simple and useful method for the large-area synthesis of graphene films. Here, we have investigated how to adjust and optimize process conditions for the synthesis of single-layer graphene films by LPCVD. Through our experimental procedure, uniform and high-quality graphene films could be grown on Cu foil at 1000 °C for 20 min with an H 2 flow rate of 20 sccm, CH 4 flow rate of 40 sccm, total pressure of 1.7 Torr, and a fast cooling rate (>10 °C/s). In a Raman spectrum measured from synthesized graphene film, we found that the full width at half-maximum (FWHM) of a symmetric 2D peak centered at 2682.5 cm -1 was 34 cm -1 and the 2D-to-G intensity ratio was 1.35.