Fabrication of highly regular suspended graphene nanoribbons through a one-step electron beam lithography process

摘要

A method to obtain pre-oriented large longitudinal 1-D arrays of identical suspended graphene nanoribbons is presented. Mechanical exfoliation from graphite was done in order to deposit single- and multiple-layered graphene over a Polymethyl-Methacrylate (PMMA) substrate, which is used as a sacrificial material. Electron beam lithography (EBL) is used to define the anchors and the suspended part of the structures. The method allows achieving a high number of graphene suspended nanoribbons with a very regular width and length. The main advantage of the method, from the process point of view, with respect to other standard procedures is that only one EBL step is needed in the whole sequence, so that the overall process is extremely simplified.