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arXiv · 2105.03182

A Versatile Post-Doping Towards Two-Dimensional Semiconductors

Y. Murai·S. Zhang·T. Hotta·Z. Liu·Y. Miyata·T. Irisawa·Y. Gao·M. Maruyama·S. Okada·H. Mogi·T. Sato·S. Yoshida·H. Shigekawa·Takashi Taniguchi·Kenji Watanabe·R. Kitaura
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Abstract

We have developed a simple and straightforward way to realize controlled post-doping towards 2D transition metal dichalcogenides (TMDs). The key idea is to use low-kinetic energy dopant beams and a high-flux chalcogen beam at the same time, leading to substitutional doping with controlled dopant densities. Atomic-resolution transmission electron microscopy has revealed that dopant atoms injected toward TMDs are incorporated substitutionally into the hexagonal framework of TMDs. Electronic properties of doped TMDs (Nb-doped WSe2) have shown drastic change, p-type action with more than two orders of magnitude increase in on current. Position-selective doping has also been demonstrated by the post-doping toward TMDs with a patterned mask on the surface. The post-doping method developed in this work can be a versatile tool for 2D-based next-generation electronics in the future.

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Y. Murai, S. Zhang, T. Hotta, Z. Liu, Y. Miyata, T. Irisawa, Y. Gao, M. Maruyama, S. Okada, H. Mogi, T. Sato, S. Yoshida, H. Shigekawa, Takashi Taniguchi, Kenji Watanabe, R. Kitaura. 2021-05-07. A Versatile Post-Doping Towards Two-Dimensional Semiconductors. https://doi.org/10.1021/acsnano.1c04584

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