▎ 摘　　要

We report observations of well developed half integer quantum Hall effect on mono layer graphene films of 7 mm x 7 mm in size. The graphene films are grown by chemical vapor deposition on copper, then transferred to SiO2/Si substrates, with typical carrier mobilities approximate to 4000 cm(2)/Vs. The large size graphene with excellent quality and electronic homogeneity demonstrated in this work is promising for graphene-based quantum Hall resistance standards and can also facilitate a wide range of experiments on quantum Hall physics of graphene and practical applications exploiting the exceptional properties of graphene. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3663972]