In Situ Oxygen Doping of Monolayer MoS2 for Novel Electronics

Jian Tang; Zheng Wei; Qinqin Wang; Yu Wang; Bo Han; Xiaomei Li; Biying Huang; Mengzhou Liao; Jieying Liu; Na Li; Yanchong Zhao; Cheng Shen; Yutuo Guo; Xuedong Bai; Peng Gao; Wei Yang; Lan Chen; Kehui Wu; Rong Yang; Dongxia Shi; Guangyu Zhang

doi:10.1002/smll.202004276

In Situ Oxygen Doping of Monolayer MoS₂ for Novel Electronics

Small. 2020 Oct;16(42):e2004276. doi: 10.1002/smll.202004276. Epub 2020 Sep 17.

Authors

Jian Tang^{1

2}, Zheng Wei^{1

2}, Qinqin Wang^{1

2}, Yu Wang^{1

2}, Bo Han³, Xiaomei Li^{1

2

3}, Biying Huang^{1

2}, Mengzhou Liao¹, Jieying Liu^{1

2}, Na Li^{1

2

4}, Yanchong Zhao^{1

2}, Cheng Shen^{1

2}, Yutuo Guo^{1

2}, Xuedong Bai^{1

2}, Peng Gao³, Wei Yang^{1

2

4

5}, Lan Chen^{1

2

4}, Kehui Wu^{1

2

4}, Rong Yang^{1

4

5}, Dongxia Shi^{1

2

5}, Guangyu Zhang^{1

2

4

5}

Affiliations

¹ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing, 100190, China.
² School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100190, China.
³ Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China.
⁴ Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China.
⁵ Beijing Key Laboratory for Nanomaterials and Nanodevices, Beijing, 100190, China.

PMID: 32939960
DOI: 10.1002/smll.202004276

Abstract

In 2D semiconductors, doping offers an effective approach to modulate their optical and electronic properties. Here, an in situ doping of oxygen atoms in monolayer molybdenum disulfide (MoS₂ ) is reported during the chemical vapor deposition process. Oxygen concentrations up to 20-25% can be reliable achieved in these doped monolayers, MoS_2- _x O_x . These oxygen dopants are in a form of substitution of sulfur atoms in the MoS₂ lattice and can reduce the bandgap of intrinsic MoS₂ without introducing in-gap states as confirmed by photoluminescence spectroscopy and scanning tunneling spectroscopy. Field effect transistors made of monolayer MoS_2- _x O_x show enhanced electrical performances, such as high field-effect mobility (≈100 cm² V^-1 s^-1 ) and inverter gain, ultrahigh devices' on/off ratio (>10⁹ ) and small subthreshold swing value (≈80 mV dec^-1 ). This in situ oxygen doping technique holds great promise on developing advanced electronics based on 2D semiconductors.

Keywords: 2D electronics; MoS2; bandgap engineering; substitutional doping.

Abstract

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