Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals
The electrical and optical properties of semiconducting transition metal dichalcogenides (TMDs) can be tuned by controlling their composition and the number of layers they have. Among various TMDs, the monolayer WSe<sub>2</sub> has a direct bandgap of 1.65 eV and exhibits p-type or bipol...
Main Authors: | , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2019-11-01
|
Series: | Nanomaterials |
Subjects: | |
Online Access: | https://www.mdpi.com/2079-4991/9/11/1642 |
_version_ | 1819058600500264960 |
---|---|
author | Hyeon-Sik Jang Jae-Young Lim Seog-Gyun Kang Sang-Hwa Hyun Sana Sandhu Seok-Kyun Son Jae-Hyun Lee Dongmok Whang |
author_facet | Hyeon-Sik Jang Jae-Young Lim Seog-Gyun Kang Sang-Hwa Hyun Sana Sandhu Seok-Kyun Son Jae-Hyun Lee Dongmok Whang |
author_sort | Hyeon-Sik Jang |
collection | DOAJ |
description | The electrical and optical properties of semiconducting transition metal dichalcogenides (TMDs) can be tuned by controlling their composition and the number of layers they have. Among various TMDs, the monolayer WSe<sub>2</sub> has a direct bandgap of 1.65 eV and exhibits p-type or bipolar behavior, depending on the type of contact metal. Despite these promising properties, a lack of efficient large-area production methods for high-quality, uniform WSe<sub>2</sub> hinders its practical device applications. Various methods have been investigated for the synthesis of large-area monolayer WSe<sub>2</sub>, but the difficulty of precisely controlling solid-state TMD precursors (WO<sub>3</sub>, MoO<sub>3</sub>, Se, and S powders) is a major obstacle to the synthesis of uniform TMD layers. In this work, we outline our success in growing large-area, high-quality, monolayered WSe<sub>2</sub> by utilizing methane (CH<sub>4</sub>) gas with precisely controlled pressure as a promoter. When compared to the catalytic growth of monolayered WSe<sub>2</sub> without a gas-phase promoter, the catalytic growth of the monolayered WSe<sub>2</sub> with a CH<sub>4</sub> promoter reduced the nucleation density to 1/1000 and increased the grain size of monolayer WSe<sub>2</sub> up to 100 μm. The significant improvement in the optical properties of the resulting WSe<sub>2</sub> indicates that CH<sub>4</sub> is a suitable candidate as a promoter for the synthesis of TMD materials, because it allows accurate gas control. |
first_indexed | 2024-12-21T13:57:47Z |
format | Article |
id | doaj.art-c4bf80f1d80f4511bffad89185ffedca |
institution | Directory Open Access Journal |
issn | 2079-4991 |
language | English |
last_indexed | 2024-12-21T13:57:47Z |
publishDate | 2019-11-01 |
publisher | MDPI AG |
record_format | Article |
series | Nanomaterials |
spelling | doaj.art-c4bf80f1d80f4511bffad89185ffedca2022-12-21T19:01:29ZengMDPI AGNanomaterials2079-49912019-11-01911164210.3390/nano9111642nano9111642Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> CrystalsHyeon-Sik Jang0Jae-Young Lim1Seog-Gyun Kang2Sang-Hwa Hyun3Sana Sandhu4Seok-Kyun Son5Jae-Hyun Lee6Dongmok Whang7School of Advanced Materials Science and Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), 2066, Seobu-Ro, Jangan-Gu, Suwon-Si, Gyeonggi-Do 16419, KoreaSchool of Advanced Materials Science and Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), 2066, Seobu-Ro, Jangan-Gu, Suwon-Si, Gyeonggi-Do 16419, KoreaSchool of Advanced Materials Science and Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), 2066, Seobu-Ro, Jangan-Gu, Suwon-Si, Gyeonggi-Do 16419, KoreaDepartment of Energy Systems Research and Department of Materials Science and Engineering, Ajou University, Suwon, Gyeonggi-Do 16499, KoreaSchool of Advanced Materials Science and Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), 2066, Seobu-Ro, Jangan-Gu, Suwon-Si, Gyeonggi-Do 16419, KoreaDepartment of Physics, Mokpo National University, Muan-gun, Jeollanam-Do 58554, KoreaDepartment of Energy Systems Research and Department of Materials Science and Engineering, Ajou University, Suwon, Gyeonggi-Do 16499, KoreaSchool of Advanced Materials Science and Engineering and SKKU Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University (SKKU), 2066, Seobu-Ro, Jangan-Gu, Suwon-Si, Gyeonggi-Do 16419, KoreaThe electrical and optical properties of semiconducting transition metal dichalcogenides (TMDs) can be tuned by controlling their composition and the number of layers they have. Among various TMDs, the monolayer WSe<sub>2</sub> has a direct bandgap of 1.65 eV and exhibits p-type or bipolar behavior, depending on the type of contact metal. Despite these promising properties, a lack of efficient large-area production methods for high-quality, uniform WSe<sub>2</sub> hinders its practical device applications. Various methods have been investigated for the synthesis of large-area monolayer WSe<sub>2</sub>, but the difficulty of precisely controlling solid-state TMD precursors (WO<sub>3</sub>, MoO<sub>3</sub>, Se, and S powders) is a major obstacle to the synthesis of uniform TMD layers. In this work, we outline our success in growing large-area, high-quality, monolayered WSe<sub>2</sub> by utilizing methane (CH<sub>4</sub>) gas with precisely controlled pressure as a promoter. When compared to the catalytic growth of monolayered WSe<sub>2</sub> without a gas-phase promoter, the catalytic growth of the monolayered WSe<sub>2</sub> with a CH<sub>4</sub> promoter reduced the nucleation density to 1/1000 and increased the grain size of monolayer WSe<sub>2</sub> up to 100 μm. The significant improvement in the optical properties of the resulting WSe<sub>2</sub> indicates that CH<sub>4</sub> is a suitable candidate as a promoter for the synthesis of TMD materials, because it allows accurate gas control.https://www.mdpi.com/2079-4991/9/11/1642tmd2d materialwse<sub>2</sub>monolayermethane promotersingle-crystal |
spellingShingle | Hyeon-Sik Jang Jae-Young Lim Seog-Gyun Kang Sang-Hwa Hyun Sana Sandhu Seok-Kyun Son Jae-Hyun Lee Dongmok Whang Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals Nanomaterials tmd 2d material wse<sub>2</sub> monolayer methane promoter single-crystal |
title | Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals |
title_full | Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals |
title_fullStr | Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals |
title_full_unstemmed | Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals |
title_short | Methane-Mediated Vapor Transport Growth of Monolayer WSe<sub>2</sub> Crystals |
title_sort | methane mediated vapor transport growth of monolayer wse sub 2 sub crystals |
topic | tmd 2d material wse<sub>2</sub> monolayer methane promoter single-crystal |
url | https://www.mdpi.com/2079-4991/9/11/1642 |
work_keys_str_mv | AT hyeonsikjang methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT jaeyounglim methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT seoggyunkang methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT sanghwahyun methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT sanasandhu methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT seokkyunson methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT jaehyunlee methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals AT dongmokwhang methanemediatedvaportransportgrowthofmonolayerwsesub2subcrystals |