title: Low resistance metal contacts to MoS2 devices with nickel-etched-graphene electrodes.
abstract: We report an approach to achieve low-resistance contacts to MoS2 transistors with the intrinsic performance of the MoS2 channel preserved. Through a dry transfer technique and a metal-catalyzed graphene treatment process, nickel-etched-graphene electrodes were fabricated on MoS2 that yield contact resistance as low as 200 Ω · μm. The substantial contact enhancement (∼ 2 orders of magnitude), as compared to pure nickel electrodes, is attributed to the much smaller work function of nickel-graphene electrodes, together with the fact that presence of zigzag edges in the treated graphene surface enhances tunneling between nickel and graphene. To this end, the successful fabrication of a clean graphene-MoS2 interface and a low resistance nickel-graphene interface is critical for the experimentally measured low contact resistance. The potential of using graphene as an electrode interlayer demonstrated in this work paves the way toward achieving high performance next-generation transistors.
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore , Singapore 117583.
authors.forename: Wei Sun
authors.initials: WS
authors.lastname: Leong
authors.forename: Xin
authors.initials: X
authors.lastname: Luo
authors.forename: Yida
authors.initials: Y
authors.lastname: Li
authors.forename: Khoong Hong
authors.initials: KH
authors.lastname: Khoo
authors.forename: Su Ying
authors.initials: SY
authors.lastname: Quek
authors.forename: John T L
authors.initials: JT
authors.lastname: Thong
keywords: Transition metal dichalcogenide; contact resistance; field-effect transistor; graphene; heterostructure; molybdenum disulfide