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arXiv · 1707.05197

Intrinsic p-type W-based transition metal dichalcogenide by substitutional Ta-doping

Yajun Fu·Mingsheng Long·Anyuan Gao·Yu Wang·Chen Pan·Xiaowei Liu·Junwen Zeng·Kang Xu·Lili Zhang·Erfu Liu·Weida Hu·Xiaomu Wang·Feng Miao
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Abstract

Two-dimensional (2D) transition metal dichalcogenides (TMDs) have recently emerged as promising candidates for future electronics and optoelectronics. While most of TMDs are intrinsic n-type semiconductors due to electron donating which originates from chalcogen vacancies, obtaining intrinsic high-quality p-type semiconducting TMDs has been challenging. Here, we report an experimental approach to obtain intrinsic p-type Tungsten (W)-based TMDs by substitutional Ta-doping. The obtained few-layer Ta-doped WSe2 (Ta0.01W0.99Se2) field-effect transistor (FET) devices exhibit competitive p-type performances, including ~10^6 current on/off at room temperature. We also demonstrate high quality van der Waals (vdW) p-n heterojunctions based on Ta0.01W0.99Se2/MoS2 structure, which exhibit nearly ideal diode characteristics (with an ideality factor approaching 1 and a rectification ratio up to 10^5) and excellent photodetecting performance. Our study suggests that substitutional Ta-doping holds great promise to realize intrinsic p-type W-based TMDs for future electronic and photonic applications.

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Yajun Fu, Mingsheng Long, Anyuan Gao, Yu Wang, Chen Pan, Xiaowei Liu, Junwen Zeng, Kang Xu, Lili Zhang, Erfu Liu, Weida Hu, Xiaomu Wang, Feng Miao. 2017-07-17. Intrinsic p-type W-based transition metal dichalcogenide by substitutional Ta-doping. https://doi.org/10.1063/1.4995400

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