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SnSe₂ Field-Effect Transistor with High On/Off Ratio and Polarity-Switchable Photoconductivity.

ABSTRACT: SnSe₂ field-effect transistor was fabricated based on exfoliated few-layered SnSe₂ flake, and its electrical and photoelectric properties have been investigated in detail. With the help of a drop of de-ionized (DI) water, the SnSe₂ FET can achieve an on/off ratio as high as ~ 10⁴ within 1 V bias, which is ever extremely difficult for SnSe₂ due to its ultrahigh carrier density (10¹⁸/cm³). Moreover, the subthreshold swing and mobility are both improved to ∼ 62 mV/decade and ~ 127 cm² V^-1 s^-1 at 300 K, which results from the efficient screening by the liquid dielectric gate. Interestingly, the SnSe₂ FET exhibits a gate bias-dependent photoconductivity, in which a competition between the carrier concentration and the mobility under illumination plays a key role in determining the polarity of photoconductivity.

SUBMITTER: Xu H

PROVIDER: S-EPMC6326916 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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SnSe2 Field-Effect Transistor with High On/Off Ratio and Polarity-Switchable Photoconductivity.

Xu Hong H Xing Jie J Huang Yuan Y Ge Chen C Lu Jinghao J Han Xu X Du Jianyu J Hao Huiying H Dong Jingjing J Liu Hao H

Nanoscale research letters 20190109 1

SnSe2 field-effect transistor was fabricated based on exfoliated few-layered SnSe2 flake, and its electrical and photoelectric properties have been investigated in detail. With the help of a drop of de-ionized (DI) water, the SnSe2 FET can achieve an on/off ratio as high as ~ 104 within 1 V bias, which is ever extremely difficult for SnSe2 due to its ultrahigh carrier density (1018/cm3). Moreover, the subthreshold swing ...[more]

PMID: 30627821

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