Chen, J., Zuo, Y., Ong, C. Y., He, J., Yang, Y., Wong, L. M., Zhang, X., & Yang, M. (2024). Modulating interface performance between 2D semiconductor MoSi2N4 and its native high-k dielectric Si3N4. Journal of Materials Chemistry C, 12(28), 10718–10725. https://doi.org/10.1039/d4tc01938e
Abstract:
Two-dimensional (2D) transition metal silicon nitrides (MSi2N4: M denotes Mo or W) are promising
channel materials for nanoelectronics owing to their attractive structural and electronic properties. The
integration of high-k dielectrics into 2D semiconductors MSi2N4 is one of the vital steps for achieving
high-performance electronic devices, which however remains challenging. In this study, we propose
silicon nitride (Si3N4) as the native high-k dielectric for 2D MSi2N4 and reveal their interfacial properties.
Using first-principles calculations, we show that a high-performance interface can be formed, as
supported by weak interface interaction, insignificant charge density redistribution, and nearly intact
electronic properties of monolayer MSi2N4 with the integration of Si3N4. We further demonstrate that
interfacial hydrogenation can effectively passivate the dangling bonds at the Si3N4 surface, leading to
improved interface performance. Importantly, this interfacial hydrogenation does not bring a detrimental
effect to both the high-k dielectric and the 2D semiconductors, as it is thermodynamically and
kinetically stable at the Si3N4 surface. These results provide a deep understanding for the integration of
high-k dielectrics on 2D semiconductors MSi2N4, design a viable interfacial engineering strategy to
improve the interface performance, and therefore could be useful for the development of 2D MSi2N4
based high-performance electronics.
License type:
Publisher Copyright
Funding Info:
This research was supported by the National Key R&D Program of the Ministry of Science and Technology of China (project number: 2022YFA1203804), the Hong Kong Polytechnic University (project number: ZE2F, CE04, and ZE2X) and PolyU RCNN (Project No.: CE0H), and Research Grants Council, Hong Kong (project number: F-PP8T).