Improving the device performances of two-dimensional semiconducting transition metal dichalcogenides: Three strategies

Abstract

Two-dimensional (2D) semiconductors are emerging as promising candidates for the next-generation nanoelectronics. As a type of unique channel materials, 2D semiconducting transition metal dichalcogenides (TMDCs), such as MoS₂ and WS₂, exhibit great potential for the state-of-the-art field-effect transistors owing to their atomically thin thicknesses, dangling-band free surfaces, and abundant band structures. Even so, the device performances of 2D semiconducting TMDCs are still failing to reach the theoretical values so far, which is attributed to the intrinsic defects, excessive doping, and daunting contacts between electrodes and channels. In this article, we review the up-to-date three strategies for improving the device performances of 2D semiconducting TMDCs: (i) the controllable synthesis of wafer-scale 2D semiconducting TMDCs single crystals to reduce the evolution of grain boundaries, (ii) the ingenious doping of 2D semiconducting TMDCs to modulate the band structures and suppress the impurity scatterings, and (iii) the optimization design of interfacial contacts between electrodes and channels to reduce the Schottky barrier heights and contact resistances. In the end, the challenges regarding the improvement of device performances of 2D semiconducting TMDCs are highlighted, and the further research directions are also proposed. We believe that this review is comprehensive and insightful for downscaling the electronic devices and extending the Moore’s law.

Graphical abstract

Keywords

2D semiconductor / transition metal dichalcogenides / wafer-scale single crystal / ingenious doping / interfacial contact / device performance

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Acknowledgements

This work was supported by the National Key R&D Program of China (Grant Nos. 2018YFA0703700 and 2021YFA1200800), the National Natural Science Foundation of China (Grant Nos. 91964203 and 92164103), the Beijing National Laboratory for Molecular Sciences (Grant No. BNLMS202001), and the Fundamental Research Funds for the Central Universities (Grant No. 2042021kf0029).

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