Smoothening of wrinkles in CVD-grown hexagonal boron nitride films
Hexagonal boron nitride (h-BN) is an ideal substrate for two-dimensional (2D) materials because of its unique electrically insulating nature, atomic smoothness and low density of dangling bonds. Although mechanical exfoliation from bulk crystals produces the most pristine flakes, scalable fabricatio...
| Huvudupphovsmän: | , , , , , , , , |
|---|---|
| Övriga upphovsmän: | |
| Materialtyp: | Journal Article |
| Språk: | English |
| Publicerad: |
2020
|
| Ämnen: | |
| Länkar: | https://hdl.handle.net/10356/137103 |
| _version_ | 1826112543992578048 |
|---|---|
| author | Lin, Jinjun Tay, Roland Yingjie Li, Hongling Jing, Lin Tsang, Siu Hon Wang, Hong Zhu, Minmin McCulloch, Dougal G. Teo, Edwin Hang Tong |
| author2 | School of Electrical and Electronic Engineering |
| author_facet | School of Electrical and Electronic Engineering Lin, Jinjun Tay, Roland Yingjie Li, Hongling Jing, Lin Tsang, Siu Hon Wang, Hong Zhu, Minmin McCulloch, Dougal G. Teo, Edwin Hang Tong |
| author_sort | Lin, Jinjun |
| collection | NTU |
| description | Hexagonal boron nitride (h-BN) is an ideal substrate for two-dimensional (2D) materials because of its unique electrically insulating nature, atomic smoothness and low density of dangling bonds. Although mechanical exfoliation from bulk crystals produces the most pristine flakes, scalable fabrication of devices is still dependent on other more direct synthetic routes. To date, the most utilized method to synthesize large-area h-BN films is by chemical vapor deposition (CVD) using catalytic metal substrates. However, a major drawback for such synthetic films is the manifestation of thermally-induced wrinkles, which severely disrupt the smoothness of the h-BN films. Here, we provide a detailed characterization study of the microstructure of h-BN wrinkles and demonstrate an effective post-synthesis smoothening route by thermal annealing in air. The smoothened h-BN film showed an improved surface smoothness by up to 66% and resulted in a much cleaner surface due to the elimination of polymer residues with no substantial oxidative damage to the film. The unwrinkling effect is attributed to the hydroxylation of the h-BN film as well as the substrate surface, resulting in a reduction in adhesion energy at the interface. Dehydroxylation occurs over time under ambient conditions at room temperature and the smoothened film can be restored back with the intrinsic properties of h-BN. This work provides an efficient route to achieve smoother h-BN films, which are beneficial for high-performance 2D heterostructure devices. |
| first_indexed | 2024-10-01T03:08:47Z |
| format | Journal Article |
| id | ntu-10356/137103 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T03:08:47Z |
| publishDate | 2020 |
| record_format | dspace |
| spelling | ntu-10356/1371032020-06-01T10:26:30Z Smoothening of wrinkles in CVD-grown hexagonal boron nitride films Lin, Jinjun Tay, Roland Yingjie Li, Hongling Jing, Lin Tsang, Siu Hon Wang, Hong Zhu, Minmin McCulloch, Dougal G. Teo, Edwin Hang Tong School of Electrical and Electronic Engineering School of Materials Science & Engineering Temasek Laboratories Engineering::Electrical and electronic engineering Hexagonal Boron Nitride Wrinkles Hexagonal boron nitride (h-BN) is an ideal substrate for two-dimensional (2D) materials because of its unique electrically insulating nature, atomic smoothness and low density of dangling bonds. Although mechanical exfoliation from bulk crystals produces the most pristine flakes, scalable fabrication of devices is still dependent on other more direct synthetic routes. To date, the most utilized method to synthesize large-area h-BN films is by chemical vapor deposition (CVD) using catalytic metal substrates. However, a major drawback for such synthetic films is the manifestation of thermally-induced wrinkles, which severely disrupt the smoothness of the h-BN films. Here, we provide a detailed characterization study of the microstructure of h-BN wrinkles and demonstrate an effective post-synthesis smoothening route by thermal annealing in air. The smoothened h-BN film showed an improved surface smoothness by up to 66% and resulted in a much cleaner surface due to the elimination of polymer residues with no substantial oxidative damage to the film. The unwrinkling effect is attributed to the hydroxylation of the h-BN film as well as the substrate surface, resulting in a reduction in adhesion energy at the interface. Dehydroxylation occurs over time under ambient conditions at room temperature and the smoothened film can be restored back with the intrinsic properties of h-BN. This work provides an efficient route to achieve smoother h-BN films, which are beneficial for high-performance 2D heterostructure devices. NRF (Natl Research Foundation, S’pore) Accepted version 2020-02-25T07:29:41Z 2020-02-25T07:29:41Z 2018 Journal Article Lin, J., Tay, R. Y., Li, H., Jing, L., Tsang, S. H., Wang, H., . . . Teo, E. H. T. (2018). Smoothening of wrinkles in CVD-grown hexagonal boron nitride films. Nanoscale, 10(34), 16243-16251. doi:10.1039/C8NR03984D 2040-3364 https://hdl.handle.net/10356/137103 10.1039/C8NR03984D 34 10 16243 16251 en Nanoscale © 2018 The Royal Society of Chemistry. All rights reserved. This paper was published in Nanoscale and is made available with permission of The Royal Society of Chemistry. application/pdf |
| spellingShingle | Engineering::Electrical and electronic engineering Hexagonal Boron Nitride Wrinkles Lin, Jinjun Tay, Roland Yingjie Li, Hongling Jing, Lin Tsang, Siu Hon Wang, Hong Zhu, Minmin McCulloch, Dougal G. Teo, Edwin Hang Tong Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title | Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title_full | Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title_fullStr | Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title_full_unstemmed | Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title_short | Smoothening of wrinkles in CVD-grown hexagonal boron nitride films |
| title_sort | smoothening of wrinkles in cvd grown hexagonal boron nitride films |
| topic | Engineering::Electrical and electronic engineering Hexagonal Boron Nitride Wrinkles |
| url | https://hdl.handle.net/10356/137103 |
| work_keys_str_mv | AT linjinjun smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT tayrolandyingjie smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT lihongling smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT jinglin smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT tsangsiuhon smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT wanghong smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT zhuminmin smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT mccullochdougalg smootheningofwrinklesincvdgrownhexagonalboronnitridefilms AT teoedwinhangtong smootheningofwrinklesincvdgrownhexagonalboronnitridefilms |