We report on electronic properties of graphene synthesized by chemical vapor deposition (CVD) on copper then transferred to SiO2 /Si. Wafer-scale (up to 4 in.) graphene films have been synthesized, consisting dominantly of monolayer graphene as indicated by spectroscopic Raman mapping. Low temperature transport measurements are performed on microdevices fabricated from such CVD graphene, displaying ambipolar field effect (with on/off ratio ∼5 and carrier mobilities up to ∼3000 cm2 /V s) and "half-integer" quantum Hall effect, a hall-mark of intrinsic electronic properties of monolayer graphene. We also observe weak localization and extract information about phase coherence and scattering of carriers. © 2010 American Institute of Physics.