Evaluation of multilayer graphene for advanced interconnects

In this work we are electrically characterizing multilayer graphene ribbons as potential Cu replacement towards future interconnect applications. We are comparing their performance with single-layer ribbons and we are reporting on sheet resistance, mobility and mean free path. We are additionally characterizing the contact properties for Pd contacts in top and edge configuration. Our results show high current carrying capacity for the multilayer ribbons and lower sheet resistance. Edge contacts to multilayer ribbons seem a promising approach for the decrease of the contact resistivity. Values of sheet resistance Rs ~ 280 Ω and contact resistivity Rc*W ~ 325 Ω·μm are measured for multilayer samples and edge contacts. Although the calculated ribbon mean free path is high for single-layer graphene (MFPSLG ~ 60 nm), it is comparable with the MFP of Cu for the multilayer samples (MFPFLG ~ 30 nm). Intercalation is a potential approach for improvement of the multilayer wire properties.