The contact resistance at two-dimensional graphene/MoS2 lateral heterojunctions is theoretically studied, using first-principles simulations based on density functional theory and the nonequilibrium Green's function method. The computed contact resistance lies in the range of 102 to 104 Ω μm, depending on the contact edge symmetry (armchair or zigzag) and termination (Mo and/or S terminated). This large variation in the contact resistance arises from the variation in the interface barrier height, which is sensitive to the presence of polar C-Mo bonds or sulfur dangling bonds at the interface. These results highlight that the control of the edge symmetry and/or edge termination is crucial to achieve a low contact resistance (in the range of a few hundred ohms micrometer) at graphene/MoS2 lateral heterojunctions for 2D material-based field-effect devices.

1.
S. Z.
Butler
,
S. M.
Hollen
,
L. Y.
Cao
,
Y.
Cui
,
J. A.
Gupta
,
H. R.
Gutiérrez
,
T. F.
Heinz
,
S. S.
Hong
,
J. X.
Huang
,
A. F.
Ismach
 et al., “
Progress, challenges, and opportunities in two-dimensional materials beyond graphene
,”
ACS Nano
7
,
2898
(
2013
).
2.
G.
Fiori
,
F.
Bonaccorso
,
G.
Iannaccone
,
T.
Palacios
,
D.
Neumaier
,
A.
Seabaugh
,
S. K.
Banerjee
, and
L.
Colombo
, “
Electronics based on two-dimensional materials
,”
Nat. Nanotechnol.
9
,
768
(
2014
).
3.
F.
Schwierz
,
J.
Pezoldt
, and
R.
Granzner
, “
Two-dimensional materials and their prospects in transistor electronics
,”
Nanoscale
7
,
8261
(
2015
).
4.
A.
Molle
,
J.
Goldberger
,
M.
Houssa
,
Y.
Xu
,
S. C.
Zhang
, and
D.
Akinwande
, “
Buckled two-dimensional Xene sheets
,”
Nat. Mater.
16
,
163
(
2017
).
5.
J. A.
Robinson
, “
2D for beyond CMOS
,”
APL Mater.
6
,
058202
(
2018
).
6.
A. K.
Geim
and
I. V.
Grigorieva
, “
Van der Waals heterostructures
,”
Nature
499
,
419
(
2013
).
7.
C.
Huang
,
S.
Wu
,
A. M.
Sanchez
,
J. J. P.
Peters
,
R.
Beanland
,
J. S.
Ross
,
P.
Rivera
,
W.
Yao
,
D. H.
Cobden
, and
X.
Xu
, “
Lateral heterojunctions with monolayer MoSe2-WSe2 semiconductors
,”
Nat. Mater.
13
,
1096
(
2014
).
8.
Y.
Gong
,
J.
Lin
,
X.
Wang
,
G.
Shi
,
S.
Lei
,
Z.
Lin
,
X.
Zou
,
G.
Ye
,
R.
Vajtai
,
B. I.
Yakobson
,
H.
Terrones
,
M.
Terrones
,
B. K.
Tay
,
J.
Lou
,
S. T.
Pantelides
,
Z.
Liu
,
W.
Zhou
, and
P. M.
Ajayan
, “
Vertical and in-plane heterostructures from WS2/MoS2 monolayers
,”
Nat. Mater.
13
,
1135
(
2014
).
9.
Q. A.
Vu
,
J. H.
Lee
,
V. L.
Nguyen
,
Y. S.
Shin
,
S. C.
Lim
,
K.
Lee
,
J.
Heo
,
S.
Park
,
K.
Kim
, and
Y. H.
Lee
, “
Tuning carrier tunneling in van der Waals heterostructures for ultrahigh detectivity
,”
Nano Lett.
17
,
453
(
2017
).
10.
C.
Zhang
,
M. Y.
Li
,
J.
Tersoff
,
Y.
Han
,
Y.
Su
,
L. J.
Li
,
D. A.
Muller
, and
C. K.
Shih
, “
Strain distributions and their influence in electronic structures of WSe2-MoS2 laterally strained heterojunctions
,”
Nat. Nanotechnol.
13
,
152
(
2018
).
11.
D.
Unuchek
,
A.
Ciarrocchi
,
A.
Avsar
,
K.
Watanabe
,
T.
Taniguchi
, and
A.
Kis
, “
Room-temperature electrical control of exciton flux in a van der Waals heterostructure
,”
Nature
560
,
340
(
2018
).
12.
A.
Allain
,
J.
Kang
,
K.
Banerjee
, and
A.
Kis
, “
Electrical contacts to two-dimensional semiconductors
,”
Nat. Mater.
14
,
1195
(
2015
).
13.
G.
Yoo
,
S.
Lee
,
B.
Yoo
,
C.
Han
,
S.
Kim
, and
M. S.
Oh
, “
Electrical contact analysis of multilayer MoS2 transistor with molybdenum source/drain electrodes
,”
IEEE Electron Device Lett.
36
,
1215
(
2015
).
14.
J.
Meng
,
H. D.
Song
,
C. Z.
Li
,
Y.
Jin
,
L.
Tang
,
D.
Liu
,
Z. M.
Liao
,
F.
Xiu
, and
D. P.
Yu
, “
Lateral graphene p-n junctions formed by the graphene/MoS2 hybrid interface
,”
Nanoscale
7
,
11611
(
2015
).
15.
M. H. D.
Guimaraes
,
H.
Gao
,
Y.
Han
,
K.
Kang
,
S.
Xie
,
C. J.
Kim
,
D. A.
Muller
,
D. C.
Ralph
, and
J.
Park
, “
Atomically thin ohmic edge contacts between two-dimensional materials
,”
ACS Nano
10
,
6392
(
2016
).
16.
M.
Zhao
,
Y.
Ye
,
Y.
Han
,
Y.
Xia
,
H.
Zhu
,
S.
Wang
,
Y.
Wang
,
D. A.
Muller
, and
X.
Zhang
, “
Large-scale chemical assembly of atomically thin transistors and circuits
,”
Nat. Nanotechnol.
11
,
954
(
2016
).
17.
X.
Ling
,
Y.
Lin
,
Q.
Ma
,
Z.
Wang
,
Y.
Song
,
L.
Yu
,
S.
Huang
,
W.
Fang
,
X.
Zhang
,
A. L.
Hsu
,
Y.
Bie
,
Y.-H.
Lee
,
Y.
Zhu
,
L.
Wu
,
J.
Li
,
P.
Jarillo-Herrero
,
M.
Dresselhaus
,
T.
Palacios
, and
J.
Kong
, “
Parallel stitching of 2D materials
,”
Adv. Mater.
28
,
2322
(
2016
).
18.
X.
Liu
,
J.
Gao
,
G.
Zhang
, and
Y. W.
Zhang
, “
MoS2-graphene in-plane contact for high interfacial thermal conduction
,”
Nano Res.
10
,
2944
(
2017
).
19.
J. M.
Soler
,
E.
Artacho
,
J. D.
Gale
,
A.
Garcia
,
J.
Junquera
,
P.
Ordejon
, and
D.
Sanchez-Portal
, “
The Siesta method for ab initio order-N materials simulations
,”
J. Phys.: Condens. Matter
14
,
2745
(
2002
).
20.
J. P.
Perdew
,
K.
Burke
, and
M.
Ernzerhof
, “
Generalized gradient approximation made simple
,”
Phys. Rev. Lett.
77
,
3865
(
1996
).
21.
N.
Trouiller
and
J. L.
Martins
, “
Efficient pseudopotentials for plane-wave calculations
,”
Phys. Rev. B
43
,
1993
(
1991
).
22.
L.
Bengtsson
, “
Dipole correction for surface supercell calculations
,”
Phys. Rev. B
59
,
12301
(
1999
).
23.
M.
Brandbyge
,
J. L.
Mozos
,
P.
Ordejon
,
J.
Taylor
, and
K.
Stokbro
, “
Density-functional method for nonequilibrium electron transport
,”
Phys. Rev. B
65
,
165401
(
2002
).
24.
S.
Datta
,
Electronic Transport in Mesoscopic Systems
(
Cambridge University Press
,
Cambridge, UK
,
1995
).
25.
M. V.
Bollinger
,
K. W.
Jacobsen
, and
J. K.
Nørskov
, “
Atomic and electronic structure of MoS2 nanoparticles
,”
Phys. Rev. B
67
,
085410
(
2003
).
26.
W.
Chen
,
Y.
Yang
,
Z.
Zhang
, and
E.
Kaxiras
, “
Properties of in-plane graphene/MoS2 heterojunctions
,”
2D Mater.
4
,
045001
(
2017
).
27.
L.
Wang
,
I.
Meric
,
P. Y.
Huang
,
Q.
Gao
,
Y.
Gao
,
H.
Tran
,
T.
Taniguchi
,
K.
Watanabe
,
L. M.
Campos
, and
D. A.
Muller
, “
One-dimensional electrical contact to a two-dimensional material
,”
Science
342
,
614
(
2013
).
28.
D.
Jena
,
K.
Banerjee
, and
G. H.
Xing
, “
2D crystal semiconductors intimate contacts
,”
Nat. Mater.
13
,
1076
(
2014
).
29.
R. T.
Tung
, “
The physics and chemistry of the Schottky barrier height
,”
Appl. Phys. Rev.
1
,
011304
(
2014
).
You do not currently have access to this content.