Enhanced electrical and optical properties of single-layered MoS2 by incorporation of aluminum


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.

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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).

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Correspondence to Jang-Yeon Kwon.

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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

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  • MoS2
  • aluminum
  • incorporation
  • chemical vapor deposition
  • atomic layer deposition