Graphene; chemical vapour deposition; electron-backscattered diffraction; ethanol precursor.
The growth of graphene by chemical vapour deposition (CVD) on copper is the most promising scalable method for high-quality graphene. The use of ethanol, an economic and safe precursor, for the fast growth of graphene on copper by a home-built CVD set-up was analysed. Full coverage of uniform single-layer graphene with high crystalline quality was found on $\langle100\rangle$ textured Cu foils in just 30 s. The nucleation density of graphene islands was found to be independent of facets but the island shape showed facet dependence. Diamond-like islands were observed on Cu(100) facets while random shaped islands were seen on other facets. The last observation is discussed in terms of a competition between graphene-island growth and its relaxation rate on different facets. On Cu(100) slower island growth as compared to its relaxation leads to equilibrium shapes as opposed to other facets. Further, an observed evolution in graphene contrast in electron micrographs with time on different facets was discussed in terms of oxygen diffusion between graphene and Cu.