Nanopatterning of graphene with crystallographic orientation control

The recent papers on the nanopatterning of graphene and cutting of graphene nanoribbons were reviewed. It was found that until now the simultaneous control of crystallographic orientation and of the ribbon width in the range of nanometers was possible only by scanning tunneling lithography. The cutting process by local anodic oxidation under the AFM tip is a similar process, but due to the different physical interaction mechanisms of the STM and AFM tip with the substrate, and due to the larger radius of the AFM tip, the resolution of AFM lithography is poorer. The various cutting processes based on mobile, catalytic nanoparticles yield trenches with well defined crystallographic orientation, but have a major drawback: the location of the nanoparticles and the control of the direction in which the cutting will start are currently not predictable. The first promising results of a solid phase reduction reaction of the SiO2 substrate at the graphene edge indicate the possibility of developing a new type of lithography that will allow the realization of complex nanopatterns. Recent results pointing to the possibility of the engineered modification of graphene edges may prove useful to all lithographic processes. (C) 2010 Elsevier Ltd. All rights reserved.