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arXiv · 2108.03904

Giant modulation of the electron mobility in semiconductor Bi$_2$O$_2$Se via incipient ferroelectric phase transition

Ziye Zhu·Xiaoping Yao·Shu Zhao·Xiao Lin·Wenbin Li
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Abstract

High-mobility layered semiconductors have the potential to enable the next-generation electronics and computing. This paper demonstrates that the ultrahigh electron mobility observed in the layered semiconductor Bi$_2$O$_2$Se originates from an incipient ferroelectric transition that endows the material with a robust protection against mobility degradation by Coulomb scattering. Based on first-principles calculations of electron-phonon interaction and ionized impurity scattering, it is shown that the electron mobility of Bi$_2$O$_2$Se can reach 10$^4$ to 10$^6$ cm$^2$V$^{-1}$s$^{-1}$ over a wide range of realistic doping concentrations. Furthermore, a small elastic strain of 1.7% can drive the material toward a unique interlayer ferroelectric transition, resulting in a large increase in the dielectric permittivity and a giant enhancement of the low-temperature electron mobility by more than an order of magnitude. These results establish a new route to realize high-mobility layered semiconductors via phase and dielectric engineering.

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Ziye Zhu, Xiaoping Yao, Shu Zhao, Xiao Lin, Wenbin Li. 2022-03-28. Giant modulation of the electron mobility in semiconductor Bi$_2$O$_2$Se via incipient ferroelectric phase transition. https://doi.org/10.1021/jacs.1c12681

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