Abstract
Electrical and optical enhancements of single-layer semiconducting materials such as transition metal dichalcogenides have recently been studied to achieve sensitive properties via external treatments, such as the formation of organic/inorganic protecting layers on field-effect transistors (FETs), thermal annealing, and nano-dot doping of sensors and detectors. Here, we propose a new analytical approach to electrical and optical enhancement through a passivation process using atomic layer deposition (ALD), and demonstrate a synthesized MoS2 monolayer incorporated with Al atoms in an Al2O3 passivation layer. The incorporated Al atoms in the MoS2 monolayer are clearly observed by spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM) and TEM-energy-dispersive X-ray spectroscopy results. We demonstrate that the chemically incorporated FETs exhibit highly enhanced mobilities of approximately 3.7 cm2·V−1·s−1, forty times greater than that of as-synthesized MoS2, with a three-fold improvement in the photoluminescence properties.
Similar content being viewed by others
References
Zhang, W. J.; Huang, J.-K.; Chen, C.-H.; Chang, Y.-H.; Chen, Y.-J.; Li, L.-J. High-gain phototransistors based on a CVD MoS2 monolayer. Adv. Mater. 2013, 25, 3456–3461.
Chen, C. Y.; Qiao, H.; Lin, S. H.; Luk, C. M.; Liu, Y.; Xu, Z. Q.; Song, J. C.; Xue, Y. Z.; Li, D. L.; Yuan, J. et al. Highly responsive MoS2 photodetectors enhanced by graphene quantum dots. Sci. Rep. 2015, 5, 11830.
Tsuboi, Y.; Wang, F. J.; Kozawa, D.; Funahashi, K.; Mouri, S.; Miyauchi, Y.; Takenobu, T.; Matsuda, K. Enhanced photovoltaic performances of graphene/Si solar cells by insertion of a MoS2 thin film. Nanoscale 2015, 7, 14476–14482.
Tsai, M.-L.; Su, S.-H.; Chang, J.-K.; Tsai, D.-S.; Chen, C.-H.; Wu, C.-I.; Li, L.-J.; Chen, L.-J.; He, J.-H. Monolayer MoS2 heterojunction solar cells. ACS Nano 2014, 8, 8317–8322.
Zhang, Y. W.; Li, H.; Wang, L.; Wang, H. M.; Xie, X. M.; Zhang, S.-L.; Liu, R.; Qiu, Z.-J. Photothermoelectric and photovoltaic effects both present in MoS2. Sci. Rep. 2015, 5, 7938.
Bertolazzi, S.; Krasnozhon, D.; Kis, A. Nonvolatile memory cells based on MoS2/graphene heterostructures. ACS Nano 2013, 7, 3246–3252.
Zhang, E. Z.; Wang, W. Y.; Zhang, C.; Jin, Y. B.; Zhu, G. D.; Sun, Q. Q.; Zhang, D. W.; Zhou, P.; Xiu, F. X. Tunable charge-trap memory based on few-layer MoS2. ACS Nano 2015, 9, 612–619.
Roy, K.; Padmanabhan M.; Goswami S.; Sai, T. P.; Ramalingam, G.; Raghavan, S.; Ghosh, A. Graphene-MoS2 hybrid structures for multifunctional photoresponsive memory devices. Nat. Nanotechnol. 2013, 8, 826–830.
Lembke, D.; Kis, A. Breakdown of high-performance monolayer MoS2 transistors. ACS Nano 2012, 6, 10070–10075.
Wu, W.; De, D.; Chang, S.-C.; Wang, Y.; Peng, H. B.; Bao, J. M.; Pei, S.-S. High mobility and high on/off ratio fieldeffect transistors based on chemical vapor deposited singlecrystal MoS2 grains. Appl. Phys. Lett. 2013, 102, 142106.
Kappera, R.; Voiry, D.; Yalcin, S. E.; Branch, B.; Gupta, G.; Mohite, A. D.; Chhowalla, M. Phase-engineered low-resistance contacts for ultrathin MoS2 transistors. Nat. Mater. 2014, 13, 1128–1134.
Liu, H.; Si, M. W.; Deng, Y. X.; Neal, A. T.; Du, Y. C.; Najmaei, S.; Ajayan, P. M.; Lou, J.; Ye, P. D. Switching mechanism in single-layer molybdenum disulfide transistors: An insight into current flow across Schottky barriers. ACS Nano 2014, 8, 1031–1038.
He, G.; Ghosh, K.; Singisetti, U.; Ramamoorthy, H.; Somphonsane R.; Bohra, G.; Matsunaga. M.; Higuchi, A.; Aoki, N.; Najmaei, S. et al. Conduction mechanisms in CVD-grown monolayer MoS2 transistors: From variable-range hopping to velocity saturation. Nano Lett. 2015, 15, 5052–5058.
Fuhrer, M. S.; Hone, J. Measurement of mobility in dualgated MoS2 transistors. Nat. Nanotechnol. 2013, 8, 146–147.
Ghorbani-Asl, M.; Enyashin, A. N.; Kuc, A.; Seifert, G.; Heine, T. Defect-induced conductivity anisotropy in MoS2 monolayers. Phys. Rev. B 2013, 88, 245440.
Santosh, K. C.; Longo, R. C.; Addou, R.; Wallace, R. M.; Cho, K. Impact of intrinsic atomic defects on the electronic structure of MoS2 monolayers. Nanotechnology 2014, 25, 375703.
Islam, M. R.; Kang, N.; Bhanu, U.; Paudel, H. P.; Erementchouk, M.; Tetard, L.; Leuenberger, M. N.; Khondaker, S. I. Tuning the electrical property via defect engineering of single layer MoS2 by oxygen plasma. Nanoscale 2014, 6, 10033–10039.
Zhou, C. J.; Wang, X. S.; Raju, S.; Lin, Z. Y.; Villaroman, D.; Huang, B. L.; Chan, H. L.-W.; Chan, M. S.; Chai, Y. Low voltage and high on/off ratio field-effect transistors based on CVD MoS2 and ultra high-k gate dielectric PZT. Nanoscale 2015, 7, 8695–8700.
Cheng, L. X.; Qin, X. Y.; Lucero, A. T.; Azcatl, A.; Huang, J.; Wallace, R. M.; Cho, K.; Kim, J. Atomic layer deposition of a high-k dielectric on MoS2 using trimethylaluminum and ozone. ACS Appl. Mater. Interfaces 2014, 6, 11834–11838.
Zhang, K. H.; Feng, S. M.; Wang, J. J.; Azcatl, A.; Lu, N.; Addou, R.; Wang, N.; Zhou, C. J.; Lerach, J.; Bojan, V. et al. Manganese doping of monolayer MoS2: The substrate is critical. Nano Lett. 2015, 15, 6586–6591.
Al-Dulaimi, N.; Lewis, D. J.; Zhong, X. L.; Malik, M. A.; O’Brien, P. Chemical vapour deposition of rhenium disulfide and rhenium-doped molybdenum disulfide thin films using single-source precursors. J. Mater. Chem. C 2016, 4, 2312–2318.
Amani, M.; Chin, M. L.; Birdwell, A. G.; O’Regan, T. P.; Najmaei, S.; Liu, Z.; Ajayan, P. M.; Lou, J.; Dubey, M. Electrical performance of monolayer MoS2 field-effect transistors prepared by chemical vapor deposition. Appl. Phys. Lett. 2013, 102, 193107.
Wang, J.; Chen, L. F.; Lu, W. J.; Zeng, M. Q.; Tan, L. F.; Ren, F.; Jiang, C. Z.; Fu, L. Direct growth of molybdenum disulfide on arbitrary insulating surfaces by chemical vapor deposition. RSC Adv. 2015, 5, 4364–4367.
Ye, M. X.; Winslow, D.; Zhang, D. Y.; Pandey, R.; Yap, Y. K. Recent advancement on the optical properties of twodimensional molybdenum disulfide (MoS2) thin films. Photonics 2015, 2, 288–307.
O’Brien, M.; McEvoy, N.; Hanlon, D.; Hallam, T.; Coleman, J. N.; Duesberg, G. S. Mapping of low-frequency Raman modes in CVD-grown transition metal dichalcogenides: Layer number, stacking orientation and resonant effects. Sci. Rep. 2016, 6, 19476.
Yang, L.; Cui, X. D.; Zhang, J. Y.; Wang, K.; Shen, M.; Zeng, S. S.; Dayeh, S. A.; Feng, L.; Xiang, B. Lattice strain effects on the optical properties of MoS2 nanosheets. Sci. Rep. 2014, 4, 5649.
Chhowalla, M.; Shin, H. S.; Eda, G.; Li, L.-J.; Loh, K. P.; Zhang, H. The chemistry of two-dimensional layered transition metal dichalcogenidenanosheets. Nat. Chem. 2013, 5, 263–275.
Wang, Q. H.; Kalantar-Zadeh, K.; Kis, A.; Coleman, J. N.; Strano, M. S. Electronics and optoelectronics of twodimensional transition metal dichalcogenides. Nat. Nanotechnol. 2012, 7, 699–712.
Jang, C.; Adam, S.; Chen, J.-H.; Williams, E. D.; Das Sarma, S.; Fuhrer, M. S. Tuning the effective fine structure constant in graphene: Opposing effects of dielectric screening on short- and long-range potential scattering. Phys. Rev. Lett. 2008, 101, 146805.
Tanaka, J.; Ueoka, Y.; Yoshitsugu, K.; Fujii, M.; Ishikawa, Y.; Uraoka, Y.; Takechi, K.; Tanabe, H. Comparison between effects of PECVD-SiOx and thermal ALD-AlOx passivation layers on characteristics of amorphous InGaZnO TFTs. ECS J. Solid State Sci. Technol. 2015, 4, Q61–Q65.
Hong, J. H.; Hu, Z. X.; Probert, M.; Li, K.; Lv, D. H.; Yang, X. N.; Gu, L.; Mao, N. N.; Feng, Q. L.; Xie, L. M. et al. Exploring atomic defects in molybdenum disulphide monolayers. Nat. Commun. 2015, 6, 6293.
Mouri, S.; Miyauchi, Y.; Matsuda, K. Tunable photoluminescence of monolayer MoS2 via chemical doping. Nano Lett. 2013, 13, 5944–5948.
Kim, Y.; Jhon, Y. I.; Park, J.; Kim, C.; Lee, S.; Jhon, Y. M. Plasma functionalization for cyclic transition between neutral and charged excitons in monolayer MoS2. Sci. Rep. 2016, 6, 21405.
Tongay, S.; Suh, J.; Ataca, C.; Fan, W.; Luce, A.; Kang, J. S.; Liu, J.; Ko, C.; Raghunathanan, R.; Zhou, J. et al. Defects activated photoluminescence in two-dimensional semiconductors: Interplay between bound, charged, and free excitons. Sci. Rep. 2013, 3, 2657.
Acknowledgements
This research was supported by the MSIT (Ministry of Science and ICT), Korea, under the ICT Consilience Creative program (IITP-2017-2017-0-01015) supervised by the IITP (Institute for information & communications Technology Promotion).
Author information
Authors and Affiliations
Corresponding author
Electronic supplementary material
Rights and permissions
About this article
Cite this article
Kim, HJ., Yang, S., Kim, H. et al. Enhanced electrical and optical properties of single-layered MoS2 by incorporation of aluminum. Nano Res. 11, 731–740 (2018). https://doi.org/10.1007/s12274-017-1682-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12274-017-1682-4