▎ 摘 要
Here we report the low-defect synthesis of bilayer graphene film on SiO2 with a nickel catalyst using pulsed laser deposition combined with rapid thermal annealing. A parametric study was performed with various initial amorphous carbon (a-C) film thicknesses and annealing temperatures and a fixed nickel catalyst film thickness. Raman spectra and mapping over large areas of up to 100 x 100 mu m(2) were used to investigate the structure and the defects of graphene films. Optimal conditions for graphene growth were an initial a-C film thickness of 2 nm and an annealing temperature of 900 degrees C. Results showed that 76% of the optimized film contained graphene bilayers, and 18% of the optimized film contained graphene monolayers. A transmittance of 87% at 550 nm is observed without any transfer process from the SiO2 substrate. This paper presents experimental guidelines for optimal synthesis conditions to control graphene growth by pulsed laser deposition.