Contacting graphene

We present a robust method for forming high quality ohmic contacts to graphene, which improves the contact resistance by nearly 6000 times compared to untreated metal/graphene interfaces. The optimal specific contact resistance for treated Ti/Au contacts is found to average <10−7 Ω cm2. Additionally, we examine Al/Au, Ti/Au, Ni/Au, Cu/Au, Pt/Au, and Pd/Au contact metallizations and find that most metallizations result in similar specific contact resistances in this work regardless of the work function difference between graphene and the metal overlayer. The results presented in this work serve as a foundation for achieving ultralow resistance ohmic contacts to graphene for high speed electronic and optoelectronic applications.