- Hexagonal Boron Nitride Crystal Growth from Iron, a Single Component Flux doi link

Auteur(s): Li Jiahan, Wang Junyong, Zhang Xiaotian, Elias C., Ye Gaihua, Evans Dylan, Eda Goki, Redwing Joan m., Cassabois G.(Corresp.), Gil B., Valvin P., He Rui, Bin Liu, Edgar James h.

(Article) Publié: Acs Nano, vol. 15 p.7032-7039 (2021)

Ref HAL: hal-03282908_v1
DOI: 10.1021/acsnano.1c00115
WoS: WOS:000645436800093
Exporter : BibTex | endNote

The highest quality hexagonal boron nitride (hBN) crystals are grown from molten solutions. For hBN crystal growth at atmospheric pressure, typically the solvent is a combination of two metals, one with a high boron solubility and the other to promote nitrogen solubility. In this study, we demonstrate that high-quality hBN crystals can be grown at atmospheric pressure using pure iron as a flux. The ability to produce excellent-quality hBN crystals using pure iron as a solvent is unexpected, given its low solubility for nitrogen. The properties of crystals produced with this flux matched the best values ever reported for hBN: a narrow Raman E2g vibration peak (7.6 cm–1) and strong phonon-assisted peaks in the photoluminescence spectra. To further test their quality, the hBN crytals were used as a substrate for WSe2 epitaxy. WSe2 was deposited with a low nucleation density, indicating the low defect density of the hBN. Lastly, the carrier tunneling through our hBN thin layers (3.5 nm) follows the Fowler–Nordheim model, with a barrier height of 3.7 eV, demonstrating hBN’s superior electrical insulating properties. This ability to produce high-quality hBN crystals in such a simple, environmentally friendly and economical process will advance two-dimensional material research by enabling integrated devices.