Fabrication of graphene nanoribbons via nanowire lithography

Graphene nanoribbons (GNRs) are the counterpart of nanotubes in graphene nanoelectronics. The search for a cheap, parallel, and deterministic technique for practical implementation of these structures is still open. Nanowire lithography (NWL) consists in using nanowires (NWs) as etch masks to transfer their one-dimensional morphology to an underlying substrate. Here, we show that oxidized silicon NWs (SiNWs) are a simple and compatible system to implement NWL on graphene. The SiNWs morphology is transferred onto a graphene flake by a low-power O-2 plasma in a deep-reactive-ion-etcher. The process leads to conformal GNRs with diameter comparable to the overlaying NW lateral dimensions. The diameter can be further reduced by Multiple O-2 etching steps. Field-effect measurements show the transition to a semiconductor for low diameters. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim