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Wafer-scale production of patterned transition metal ditelluride layers for two-dimensional metal–semiconductor contacts at the Schottky–Mott limit

Nature Electronics volume 3, pages 207–215 (2020)Cite this article

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Abstract

A key challenge in the development of two-dimensional (2D) devices is the fabrication of metal–semiconductor junctions with minimal contact resistance and depinned energy levels. An ideal solution for practical applications is to make contacts between 2D van der Waals semiconductors and 2D van der Waals metals. Here we report the wafer-scale production of patterned layers of metallic transition metal ditellurides on different substrates. Our tungsten ditelluride and molybdenum ditelluride layers, which are grown using a tellurization process applied to a precursor transition metal layer, have an electronic performance comparable to that of mechanically exfoliated flakes and can be combined with the 2D semiconductor molybdenum disulfide. The resulting metal–semiconductor junctions are free from significant disorder effects and Fermi-level pinning, and are used to create monolayer molybdenum disulfide field-effect transistors. The Schottky barrier heights of the devices also largely follow the trend of the Schottky–Mott limit.

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Fig. 1: Position-controllable growth of WTe2 atomic layers directly on a SiO2/Si substrate.
Fig. 2: Electro- and magnetotransporting behaviours of WTe2 films.
Fig. 3: Atomically thin FETs composed of the MoS2 channel and WTe2 contact.
Fig. 4: Low SB nature of (W,Mo)Te2 contacts for atomically thin FETs.

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Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.

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Acknowledgements

This work was supported by the Nano-Material Technology Development Program (Grant no. 2017M3A7B8065377) through the National Research Foundation (NRF) of Korea funded by the Ministry of Science, ICT and Future Planning. This work has benefited from the use of the facilities at UNIST Central Research Facilities.

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Authors and Affiliations

  1. School of Materials Science and Engineering and Center for Future Semiconductor Technology (FUST), Ulsan National Institute of Science and Technology (UNIST), Ulsan, Korea

    Seunguk Song, Yeoseon Sim, Se-Yang Kim, Jung Hwa Kim, Inseon Oh, Do Hee Lee, Jaewon Wang, Jinsung Kwak, Jung-Woo Yoo, Zonghoon Lee & Soon-Yong Kwon

  2. Center for Multidimensional Carbon Materials, Institute for Basic Science (IBS), Ulsan, Korea

    Yeoseon Sim, Jung Hwa Kim & Zonghoon Lee

  3. Department of Physics, Sogang University, Seoul, Korea

    Woongki Na & Hyeonsik Cheong

  4. Beijing Academy of Quantum Information Sciences, Beijing, P. R. China

    Shili Yan & Jian-Hao Chen

  5. International Center for Quantum Materials, School of Physics, Peking University, Beijing, P. R. China

    Yinan Liu & Jian-Hao Chen

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Contributions

S.S. performed most of the experiments with assistance from Y.S., S.-Y. Kim, D.H.L., J.W., S.Y., Y.L., J.K., J.-H.C.; J.H.K. and Z.L. performed the high-resolution TEM imaging of the samples; I.O. and J.-W.Y. performed the low-temperature magnetoresistance measurements; W.N. and H.C. performed the Raman measurements; S.S. and S.-Y. Kwon wrote the manuscript; all the authors revised and commented on the manuscript; S.-Y. Kwon planned and supervised the project.

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Correspondence to Soon-Yong Kwon.

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Supplementary Notes 1 and 2, Figs. 1–24 and Tables 1–3.

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Song, S., Sim, Y., Kim, SY. et al. Wafer-scale production of patterned transition metal ditelluride layers for two-dimensional metal–semiconductor contacts at the Schottky–Mott limit. Nat Electron 3, 207–215 (2020). https://doi.org/10.1038/s41928-020-0396-x

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