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

Nanoscale Research Letters

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[1] 0000 0001 2156 409X, grid.162107.3, School of Sciences, China University of Geosciences, 100083, Beijing, China;0000 0001 2156 409X, grid.162107.3, School of Sciences, China University of Geosciences, 100083, Beijing, China;0000000119573309, grid.9227.e, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China;0000000119573309, grid.9227.e, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, 100190, Beijing, China;

关键词: Field-effect transistor;    SnSe;    Photoconductivity;    On/off ratio;   

DOI  :  10.1186/s11671-019-2850-0

来源: publisher

【 摘 要 】

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.

【 授权许可】

CC BY