Quantum transport in patterned graphene nanoribbons

The paper presents the fabrication of graphene nanoribbons (GNR) on exfoliated graphene flakes on SiO₂/Si. The Si substrate is heavily doped n-type. Al metal masks were patterned by electron beam lithography and electron beam deposition. The exposed graphene was removed by O₂ plasma etching and then the metal masks were removed by Al etchant. Quantized conductance was observed in the thin GNRs which form quasi-1D transport systems due to the carrier constriction by the ribbon edge boundaries. Landauer´s formula was applied to fit the experimental data and excellent agreement was achieved.