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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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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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.
The authors declare no competing interests.
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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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