Growth of Large Area Graphene Single Crystals in Confined Reaction Space with Diffusion Driven Chemical Vapor Deposition
To synthesize large area graphene single crystals, we specifically designed a low pressure chemical vapor deposition (LPCVD) reactor with confined reaction space (L 22 mm x W 13 mm x H 50 mm) Within the confined reaction space, a uniform distribution of reactant concentrations, reduced substrate roughness, and the shift of growth kinetics toward a diffusion limited regime can be achieved, favoring the preparation of large area, high quality graphene single crystals. The gas flow field and mass transport pattern of reactants in the LPCVD system simulated with a finite element method support the advantages of using this confined reaction room for graphene growth. Using this space confined reactor together with the optimized synthesis parameters, we obtained monolayer, highly uniform, and defect free graphene single crystals of up to ~0.8 mm in diameter with the field effect mobility of mEF 4800 cm2 V 1 s 1 at room temperature. In addition, structural design of the confined reaction space by adjusting the.