Side-gated transport in focused-ion-beam-fabricated multilayered graphene nanoribbons

A study was conducted to demonstrate the patterning, exfoliation, and micromanipulation of thin graphitic discs, which were connected and patterned into nanometric ribbons, with a resist-free process, using focused ion beam (FIB) lithography and deposition. The electronic transport properties of the double side-gated nanoribbons were investigated and interpreted, with a simple model of a 1D array of tunneling junctions. The process of sample preparation consisted of a number of steps, including patterning cylindrical micropillars on a HOPG crystal, extracting thin discs from the core of the pillar and depositing at the center of prepatterned micromanipulator, obtaining 12- 8-nm-thick discs through in situ exfoliation with the glass tip, and assessing the structural quality through atomic force microscopy (AFM) imaging.