Process optimization for synthesis of high-quality graphene films by low-pressure chemical vapor deposition

Abstract

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 degrees C for 20 min with an H-2 flow rate of 20 sccm, CH4 flow rate of 40 sccm, total pressure of 1.7 Torr, and a fast cooling rate (>10 degrees 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. (C) 2012 The Japan Society of Applied Physics