Abstract
Transition metal dichalcogenides (TMDCs) are promising next-generation materials for optoelectronic devices because, at subnanometer thicknesses, they have a transparency, flexibility, and band gap in the near-infrared to visible light range. In this study, we examined continuous, large-area MoSe 2 film, grown by molecular beam epitaxy on an amorphous SiO 2 /Si substrate, which facilitated direct device fabrication without exfoliation. Spectroscopic measurements were implemented to verify the formation of a homogeneous MoSe 2 film by performing mapping on the micrometer scale and measurements at multiple positions. The crystalline structure of the film showed hexagonal (2H) rotationally stacked layers. The local strain at the grain boundaries was mapped using a geometric phase analysis, which showed a higher strain for a 30° twist angle compared to a 13° angle. Furthermore, the photon-matter interaction for the rotational stacking structures was investigated as a function of the number of layers using spectroscopic ellipsometry. The optical band gap for the grown MoSe 2 was in the near-infrared range, 1.24-1.39 eV. As the film thickness increased, the band gap energy decreased. The atomically controlled thin MoSe 2 showed promise for application to nanoelectronics, photodetectors, light emitting diodes, and valleytronics.
| Original language | English |
|---|---|
| Pages (from-to) | 30786-30796 |
| Number of pages | 11 |
| Journal | ACS Applied Materials and Interfaces |
| Volume | 9 |
| Issue number | 36 |
| DOIs | |
| Publication status | Published - 2017 Sep 13 |
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All Science Journal Classification (ASJC) codes
- Materials Science(all)
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Characterization of Rotational Stacking Layers in Large-Area MoSe 2 Film Grown by Molecular Beam Epitaxy and Interaction with Photon . / Choi, Yoon Ho; Lim, Dong Hyeok; Jeong, Jae Hun; Park, Dambi; Jeong, Kwang Sik; Kim, Minju; Song, Aeran; Chung, Hee Suk; Chung, Kwun Bum; Yi, Yeonjin; Cho, Mann-Ho.
In: ACS Applied Materials and Interfaces, Vol. 9, No. 36, 13.09.2017, p. 30786-30796.Research output: Contribution to journal › Article
TY - JOUR
T1 - Characterization of Rotational Stacking Layers in Large-Area MoSe 2 Film Grown by Molecular Beam Epitaxy and Interaction with Photon
AU - Choi, Yoon Ho
AU - Lim, Dong Hyeok
AU - Jeong, Jae Hun
AU - Park, Dambi
AU - Jeong, Kwang Sik
AU - Kim, Minju
AU - Song, Aeran
AU - Chung, Hee Suk
AU - Chung, Kwun Bum
AU - Yi, Yeonjin
AU - Cho, Mann-Ho
PY - 2017/9/13
Y1 - 2017/9/13
N2 - Transition metal dichalcogenides (TMDCs) are promising next-generation materials for optoelectronic devices because, at subnanometer thicknesses, they have a transparency, flexibility, and band gap in the near-infrared to visible light range. In this study, we examined continuous, large-area MoSe 2 film, grown by molecular beam epitaxy on an amorphous SiO 2 /Si substrate, which facilitated direct device fabrication without exfoliation. Spectroscopic measurements were implemented to verify the formation of a homogeneous MoSe 2 film by performing mapping on the micrometer scale and measurements at multiple positions. The crystalline structure of the film showed hexagonal (2H) rotationally stacked layers. The local strain at the grain boundaries was mapped using a geometric phase analysis, which showed a higher strain for a 30° twist angle compared to a 13° angle. Furthermore, the photon-matter interaction for the rotational stacking structures was investigated as a function of the number of layers using spectroscopic ellipsometry. The optical band gap for the grown MoSe 2 was in the near-infrared range, 1.24-1.39 eV. As the film thickness increased, the band gap energy decreased. The atomically controlled thin MoSe 2 showed promise for application to nanoelectronics, photodetectors, light emitting diodes, and valleytronics.
AB - Transition metal dichalcogenides (TMDCs) are promising next-generation materials for optoelectronic devices because, at subnanometer thicknesses, they have a transparency, flexibility, and band gap in the near-infrared to visible light range. In this study, we examined continuous, large-area MoSe 2 film, grown by molecular beam epitaxy on an amorphous SiO 2 /Si substrate, which facilitated direct device fabrication without exfoliation. Spectroscopic measurements were implemented to verify the formation of a homogeneous MoSe 2 film by performing mapping on the micrometer scale and measurements at multiple positions. The crystalline structure of the film showed hexagonal (2H) rotationally stacked layers. The local strain at the grain boundaries was mapped using a geometric phase analysis, which showed a higher strain for a 30° twist angle compared to a 13° angle. Furthermore, the photon-matter interaction for the rotational stacking structures was investigated as a function of the number of layers using spectroscopic ellipsometry. The optical band gap for the grown MoSe 2 was in the near-infrared range, 1.24-1.39 eV. As the film thickness increased, the band gap energy decreased. The atomically controlled thin MoSe 2 showed promise for application to nanoelectronics, photodetectors, light emitting diodes, and valleytronics.
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U2 - 10.1021/acsami.7b05475
DO - 10.1021/acsami.7b05475
M3 - Article
VL - 9
SP - 30786
EP - 30796
JO - ACS applied materials & interfaces
JF - ACS applied materials & interfaces
SN - 1944-8244
IS - 36
ER -