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Nano Research 2020, 13(4): 952-958 https://doi.org/10.1007/s12274-020-2724-x
Research Article | Issue | Published: 11 April 2020

Enormous enhancement in electrical performance of few-layered MoTe2 due to Schottky barrier reduction induced by ultraviolet ozone treatment

Show Author's Information Xiaoming Zheng1,2,  Xueao Zhang3,  Yuehua Wei2,  Jinxin Liu1,  Hang Yang2,  Xiangzhe Zhang2,  Shitan Wang1,  Haipeng Xie1,  Chuyun Deng2,  Yongli Gao1,4,  Han Huang1( )
Hunan Key Laboratory of Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha 410083, China
College of Arts and Science, National University of Defense Technology, Changsha 410073, China
College of Physical Science and Technology, Xiamen University, Xiamen 361005, China
Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA
Keywords:
Schottky barrier, MoTe2, ultraviolet ozone, surface charge transfer, air stable hole doping
Topics:
Electric field effects Field effect transistorsHole concentrationMolybdenum oxidePhotoelectron spectroscopySemiconductor doping
Cite this article:
Zheng X, Zhang X, Wei Y, et al. Enormous enhancement in electrical performance of few-layered MoTe2 due to Schottky barrier reduction induced by ultraviolet ozone treatment. Nano Research, 2020, 13(4): 952-958. https://doi.org/10.1007/s12274-020-2724-x
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Abstract Full text Electronic supplementary material About this article

Doping can improve the band alignment at the metal-semiconductor interface to modify the corresponding Schottky barrier, which is crucial for the realization of high-performance logic components. Here, we systematically investigated a convenient and effective method, ultraviolet ozone treatment, for p-type doping of MoTe2 field-effect transistors to enormously enhance the corresponding electrical performance. The resulted hole concentration and mobility are near 100 times enhanced to be ~ 1.0 × 1013 cm-2 and 101.4 cm2/(V·s), respectively, and the conductivity is improved by 5 orders of magnitude. These values are comparable to the highest ones ever obtained via annealing doping or non-lithographic fabrication methods at room temperature. Compared with the pristine one, the photoresponsivity (522 mA/W) is enhanced approximately 100 times. Such excellent performances can be attributed to the sharply reduced Schottky barrier because of the surface charge transfer from MoTe2 to MoOx (x < 3), as proved by photoemission spectroscopy. Additionally, the p-doped devices exhibit excellent stability in ambient air. Our findings show significant potential in future nanoelectronic and optoelectronic applications.


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Electronic supplementary material
About this article

Enormous enhancement in electrical performance of few-layered MoTe2 due to Schottky barrier reduction induced by ultraviolet ozone treatment

Show Author's information Xiaoming Zheng1,2, Xueao Zhang3, Yuehua Wei2, Jinxin Liu1, Hang Yang2, Xiangzhe Zhang2, Shitan Wang1, Haipeng Xie1, Chuyun Deng2, Yongli Gao1,4, Han Huang1( )
Hunan Key Laboratory of Super-microstructure and Ultrafast Process, School of Physics and Electronics, Central South University, Changsha 410083, China
College of Arts and Science, National University of Defense Technology, Changsha 410073, China
College of Physical Science and Technology, Xiamen University, Xiamen 361005, China
Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627, USA

Abstract

Doping can improve the band alignment at the metal-semiconductor interface to modify the corresponding Schottky barrier, which is crucial for the realization of high-performance logic components. Here, we systematically investigated a convenient and effective method, ultraviolet ozone treatment, for p-type doping of MoTe2 field-effect transistors to enormously enhance the corresponding electrical performance. The resulted hole concentration and mobility are near 100 times enhanced to be ~ 1.0 × 1013 cm-2 and 101.4 cm2/(V·s), respectively, and the conductivity is improved by 5 orders of magnitude. These values are comparable to the highest ones ever obtained via annealing doping or non-lithographic fabrication methods at room temperature. Compared with the pristine one, the photoresponsivity (522 mA/W) is enhanced approximately 100 times. Such excellent performances can be attributed to the sharply reduced Schottky barrier because of the surface charge transfer from MoTe2 to MoOx (x < 3), as proved by photoemission spectroscopy. Additionally, the p-doped devices exhibit excellent stability in ambient air. Our findings show significant potential in future nanoelectronic and optoelectronic applications.

Keywords: Schottky barrier, MoTe2, ultraviolet ozone, surface charge transfer, air stable hole doping

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Publication history
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Acknowledgements

Publication history

Received: 11 November 2019
Revised: 14 February 2020
Accepted: 21 February 2020
Published: 11 April 2020
Issue date: April 2020

Copyright

© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2020

Acknowledgements

We acknowledge the financial support from the National Natural Science Foundation of China (Nos. 11874427 and 11874423). Dr. Han Huang acknowledges support from the Innovation-Driven project of Central South University (No. 2017CX018) and from the Natural Science Foundation of Hunan province (No. 2016JJ1021). Mr. Xiaoming Zheng acknowledges the support from the Fundamental Research Funds for the Central Universities of Central South University (No. 2017zzts066).

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