Atomically Thin Ohmic Edge Contacts Between Two-Dimensional Materials.
With the decrease of the dimensions of electronic devices, the role played by electrical contacts is ever increasing, eventually coming to dominate the overall device volume and total resistance. This is especially problematic for monolayers of semiconducting transition-metal dichalcogenides (TMDs), which are promising candidates for atomically thin electronics. Ideal electrical contacts to them would require the use of similarly thin electrode materials while maintaining low contact resistances. Here we report a scalable method to fabricate ohmic graphene edge contacts to two representative monolayer TMDs, MoS2 and WS2. The graphene and TMD layer are laterally connected with wafer-scale homogeneity, no observable overlap or gap, and a low average contact resistance of 30 kΩ·μm. The resulting graphene edge contacts show linear current-voltage (I-V) characteristics at room temperature, with ohmic behavior maintained down to liquid helium temperatures.
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Marcos H D
MH
Guimarães
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Hui
H
Gao
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Yimo
Y
Han
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Kibum
K
Kang
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Saien
S
Xie
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Cheol-Joo
CJ
Kim
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
David A
DA
Muller
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Daniel C
DC
Ralph
Kavli Institute at Cornell for Nanoscale Science, ‡Laboratory of Atomic and Solid State Physics, §Department of Chemistry and Chemical Biology, and ∥School of Applied and Engineering Physics, Cornell University , Ithaca, New York 14853, United States.
Jiwoong
J
Park
edge contacts; graphene; heterostructure; ohmic contacts; transition-metal dichalcogenides