Large-area fabrication of periodic sub-15 nm-width single-layer graphene nanorings

A periodically aligned array of graphene nanorings (GRNRs) with a sub-15 nm linewidth at a pitch of 450 nm is fabricated with a large area, 9 cm(2) , through conventional nanoimprint lithography coupled with sophisticated metal deposition and plasma-etching processes. The existence of the single-layer GRNRs is verified by various techniques.