1. Department of Chemistry,
   
2. School of Advanced Materials Science and Engineering,
   
3. SKKU Advanced Institute of Nanotechnology,
   
4. Center for Nanotubes and Nanostructured Composites, Sungkyunkwan University, Suwon 440-746, Korea
   
5. Samsung Advanced Institute of Technology, PO Box 111, Suwon 440-600, Korea
   
6. Department of Chemistry, Pohang University of Science and Technology, Pohang 790-784, Korea
   
7. Department of Physics, Columbia University, New York, New York 10027, USA

Correspondence to: Jae-Young Choi⁵Byung Hee Hong^1,3,4 Correspondence and requests for materials should be addressed to B.H.H. (Email: byunghee@skku.edu) or J.-Y.C. (Email: jaeyoung88.choi@samsung.com).

Problems associated with large-scale pattern growth of graphene constitute one of the main obstacles to using this material in device applications¹. Recently, macroscopic-scale graphene films were prepared by two-dimensional assembly of graphene sheets chemically derived from graphite crystals and graphene oxides^{2, 3}. However, the sheet resistance of these films was found to be much larger than theoretically expected values. Here we report the direct synthesis of large-scale graphene films using chemical vapour deposition on thin nickel layers, and present two different methods of patterning the films and transferring them to arbitrary substrates. The transferred graphene films show very low sheet resistance of 280  per square, with 80 per cent optical transparency. At low temperatures, the monolayers transferred to silicon dioxide substrates show electron mobility greater than 3,700 cm² V^-1 s^-1 and exhibit the half-integer quantum Hall effect^{4, 5}, implying that the quality of graphene grown by chemical vapour deposition is as high as mechanically cleaved graphene⁶. Employing the outstanding mechanical properties of graphene⁷, we also demonstrate the macroscopic use of these highly conducting and transparent electrodes in flexible, stretchable, foldable electronics^{8, 9}.