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Low-temperature electrical conduction of plasma-treated bilayer MoS2

  • Jakub Jadwiszczak (a1) (a2) (a3) (a4), Yangbo Zhou (a4) and Hongzhou Zhang (a1) (a2) (a3)


We report on the low-temperature electrical characterization of bilayer MoS2 treated with increasing dose of oxygen:argon (1:3) plasma. We characterize the effective Schottky barrier heights as a function of plasma exposure time and observe a significant barrier lowering, with no accompanying p-type conduction in the negative bias region. Furthermore, we observe a crossover in the temperature-dependent conduction regimes below 181 K due to the plasma exposure. The Efros–Shklovskii (ES) hopping regime is seen to transform upon plasma exposure to a mixed ES/thermally-activated regime at high temperatures, and to a strongly short-range Arrhenius regime at low temperatures. We attribute the observed crossovers to a critical defect density created by the surface reaction with the plasma.


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Address all correspondence to Hongzhou Zhang at


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1.Wang, Q.H., Kalantar-Zadeh, K., Kis, A., Coleman, J.N., and Strano, M.: Electronics and Optoelectronics of two-dimensional transition metal dichalcogenides. Nat. Nanotechnol. 7, 699712 (2012).
2.Yu, Z., Ong, Z.-Y., Li, S., Xu, J.-B., Zhang, G., Zhang, Y.-W., Shi, Y., and Wang, X.: Analyzing the carrier mobility in transition-metal dichalcogenide MoS2 field-effect transistors. Adv. Funct. Mater. 27, 1604093 (2017).
3.English, C.D., Shine, G., Dorgan, V.E., Saraswat, K.C., and Pop, E.: Improved contacts to MoS2 transistors by ultra-high vacuum metal deposition. Nano Lett. 16, 38243830 (2016).
4.Chuang, S., Battaglia, C., Azcatl, A., McDonnell, S., Kang, J.S., Yin, X., Tosun, M., Kapadia, R., Fang, H., Wallace, R.M., and Javey, A.: MoS2 P-type transistors and diodes enabled by high work function MoOX contacts. Nano Lett. 14, 13371342 (2014).
5.Chen, M., Nam, H., Wi, S., Ji, L., Ren, X., Bian, L., Lu, S., and Liang, X.: Stable few-layer MoS2 rectifying diodes formed by plasma-assisted doping. Appl. Phys. Lett. 103, 142110 (2013).
6.Chen, M., Nam, H., Wi, S., Priessnitz, G., Gunawan, I.M., and Liang, X.: Multibit data storage states formed in plasma-treated MoS2 transistors. ACS Nano 8, 40234032 (2014).
7.Tao, L., Duan, X., Wang, C., Duan, X., and Wang, S.: Plasma-engineered MoS2 thin-film as an efficient electrocatalyst for hydrogen evolution reaction. Chem. Commun. 51, 74707473 (2015).
8.Giannazzo, F., Fisichella, G., Greco, G., Di Franco, S., Deretzis, I., La Magna, A., Bongiorno, C., Nicotra, G., Spinella, C., Scopelliti, M., Pignataro, B., Agnello, S., and Roccaforte, F.: Ambipolar MoS2 Transistors by nanoscale tailoring of schottky barrier using oxygen plasma functionalization. ACS Appl. Mater. Interfaces 9, 2316423174 (2017).
9.Jadwiszczak, J., O'Callaghan, C., Zhou, Y., Fox, D.S., Weitz, E., Keane, D., Cullen, C.P., O'Reilly, I., Downing, C., Shmeliov, A., Maguire, P., Gough, J.J., McGuinness, C., Ferreira, M.S., Bradley, A.L., Boland, J.J., Duesberg, G.S., Nicolosi, V., and Zhang, H.: Oxide-mediated recovery of field-effect mobility in plasma-treated MoS2. Sci. Adv. 4, eaao5031 (2018).
10.Jariwala, D., Sangwan, V.K., Late, D.J., Johns, J.E., Dravid, V.P., Marks, T.J., Lauhon, L.J., and Hersam, M.C.: Band-like Transport in high mobility unencapsulated single-layer MoS2 transistors. Appl. Phys. Lett. 102, 26 (2013).
11.Baugher, B.W.H., Churchill, H.O.H., Yang, Y., and Jarillo-Herrero, P.: Intrinsic electronic transport properties of high-quality monolayer and bilayer MoS2. Nano Lett. 13, 42124216 (2013).
12.Filanovsky, I.M. and Allam, A.: Mutual compensation of mobility and threshold voltage temperature effects with applications in CMOS circuits. IEEE Trans. Circuits Syst. I Fundam. Theory Appl. 48, 876884 (2001).
13.Shu, J.P., Wu, G.T., Guo, Y., Liu, B., Wei, X.L., and Chen, Q.: The intrinsic origin of hysteresis in MoS2 field effect transistors. Nanoscale 8, 30493056 (2016).
14.Khondaker, S.I. and Islam, M.R.: Bandgap engineering of MoS2 flakes via oxygen plasma: a layer dependent study. J. Phys. Chem. C 120, 1380113806 (2016).
15.Choudhary, N., Islam, M.R., Kang, N., Tetard, L., Jung, Y., and Khondaker, S.I.: Two-dimensional lateral heterojunction through bandgap engineering of MoS2 via oxygen plasma. J. Phys. Condens. Matter. 28, 364002 (2016).
16.Cui, N.-Y., Brown, N.M.D., and McKinley, A.: An AFM study of the topography of natural MoS2 following treatment in an RF–oxygen plasma. Appl. Surf. Sci. 151, 1728 (1999).
17.Islam, M.R., Kang, N., Bhanu, U., Paudel, H.P., Erementchouk, M., Tetard, L., Leuenberger, M.N., and Khondaker, S.I.: Tuning the electrical property via defect engineering of single layer MoS2 by oxygen plasma. Nanoscale 6, 1003310039 (2014).
18.Kim, C., Moon, I., Lee, D., Choi, M.S., Ahmed, F., Nam, S., Cho, Y., Shin, H., Park, S., and Yoo, W.J.: Fermi level pinning at electrical metal contacts of monolayer molybdenum dichalcogenides. ACS Nano 11, 15881596 (2017).
19.Wang, J., Yao, Q., Huang, C., Zou, X., Liao, L., Chen, S., Fan, Z., Zhang, K., Wu, W., and Xiao, X.: High mobility MoS2 transistor with low schottky barrier contact by using atomic thick h-BN as a tunneling layer. Adv. Mater. 28, 83028308 (2016).
20.Yildiz, A., Serin, N., Serin, T., and Kasap, M.: Crossover from nearest-neighbor hopping conduction to Efros–Shklovskii variable-range hopping conduction in hydrogenated amorphous silicon films. Jpn. J. Appl. Phys. 48, 11203 (2009).
21.Papadopoulos, N., Steele, G.A., and van der Zant, H.S.J.: Efros-Shklovskii variable range hopping and nonlinear transport in 1 T/1 T′−MoS2. Phys. Rev. B 96, 235436 (2017).
22.Kim, J.S., Kim, J., Zhao, J., Kim, S., Lee, J.H., Jin, Y., Choi, H., Moon, B.H., Bae, J.J., Lee, Y.H., and Lim, S.C.: Electrical transport properties of polymorphic MoS2. ACS Nano 10, 75007506 (2016).
23.Qiu, H., Xu, T., Wang, Z., Ren, W., Nan, H., Ni, Z., Chen, Q., Yuan, S., Miao, F., Song, F., Long, G., Shi, Y., Sun, L., Wang, J., and Wang, X.: Hopping transport through defect-induced localized states in molybdenum disulphide. Nat. Commun. 4, 2642 (2013).
24.Stanford, M.G., Pudasaini, P.R., Gallmeier, E.T., Cross, N., Liang, L., Oyedele, A., Duscher, G., Mahjouri-Samani, M., Wang, K., Xiao, K., Geohegan, D.B., Belianinov, A., Sumpter, B.G., and Rack, P.D.: High conduction hopping behavior induced in transition metal dichalcogenides by percolating defect networks: toward atomically thin circuits. Adv. Funct. Mater. 27, 1702829 (2017).
25.Matis, B.R., Garces, N.Y., Cleveland, E.R., Houston, B.H., and Baldwin, J.W.: Electronic transport in bilayer MoS2 encapsulated in HfO2. ACS Appl. Mater. Interfaces 9, 2799528001 (2017).
26.Efros, A.L. and Shklovskii, B.I.: Coulomb gap and low temperature conductivity of disordered systems. J. Phys. C: Solid State Phys. 8, L49 (1975).
27.Radisavljevic, B. and Kis, A.: Mobility engineering and a metal–insulator transition in monolayer MoS2. Nat. Mater. 12, 815820 (2013).
28.Cui, X., Lee, G.-H., Kim, Y.D., Arefe, G., Huang, P.Y., Lee, C.-H., Chenet, D.A., Zhang, X., Wang, L., Ye, F., Pizzocchero, F., Jessen, B.S., Watanabe, K., Taniguchi, T., Muller, D.A., Low, T., Kim, P., and Hone, J.: Multi-terminal transport measurements of MoS2 using a van der waals heterostructure device platform. Nat. Nanotechnol. 10, 534540 (2015).
29.Ko, T.Y., Jeong, A., Kim, W., Lee, J., Kim, Y., Lee, J.E., Ryu, G.H., Park, K., Kim, D., Lee, Z., Lee, M.H., Lee, C., and Ryu, S.: On-stack two-dimensional conversion of MoS2 into MoO3. 2D Mater. 4, 14003 (2016).
30.Dhall, R., Neupane, M.R., Wickramaratne, D., Mecklenburg, M., Li, Z., Moore, C., Lake, R.K., and Cronin, S.: Direct bandgap transition in many-layer MoS2 by plasma-induced layer decoupling. Adv. Mater. 27, 15731578 (2015).

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Low-temperature electrical conduction of plasma-treated bilayer MoS2

  • Jakub Jadwiszczak (a1) (a2) (a3) (a4), Yangbo Zhou (a4) and Hongzhou Zhang (a1) (a2) (a3)


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