Lithography-Free Fabrication of Graphene Devices
  We have developed a lithography-free, all-dry process for fabricating graphene devices using an ultrathin quartz filament as a shadow mask to avoid possible contamination of graphene during lithographic process. This technique was used to prepare devices for electrical transport as well as planar tunnel junction studies of n-layer graphene (nLG), with n = 1, 2, 3 and higher. We observed localization behavior and an apparent reduction of density of states (DOS) near the Fermi energy in nLG. 
N. Staley, H. Wang, C. Puls, J. Forster, T.N. Jackson, K. McCarthy, B.   Clouser, and Y. Liu