Ultrafast Growth of High-Quality Monolayer WSe2 on Au

5 years ago

Ultrafast Growth of High-Quality Monolayer WSe2 on Au

Xiu-Liang Ma, Hui-Ming Cheng, Yang Gao, Zhiqing Yang, Yi-Lun Hong, Wencai Ren, Mao-Lin Chen, Li-Chang Yin, Teng Ma, Zhibo Liu, Zhangting Wu, Zhenhua Ni, Dong-Ming Sun

The ultrafast growth of high-quality uniform monolayer WSe2 is reported with a growth rate of ≈26 µm s−1 by chemical vapor deposition on reusable Au substrate, which is ≈2–3 orders of magnitude faster than those of most 2D transition metal dichalcogenides grown on nonmetal substrates. Such ultrafast growth allows for the fabrication of millimeter-size single-crystal WSe2 domains in ≈30 s and large-area continuous films in ≈60 s. Importantly, the ultrafast grown WSe2 shows excellent crystal quality and extraordinary electrical performance comparable to those of the mechanically exfoliated samples, with a high mobility up to ≈143 cm2 V−1 s−1 and ON/OFF ratio up to 9 × 106 at room temperature. Density functional theory calculations reveal that the ultrafast growth of WSe2 is due to the small energy barriers and exothermic characteristic for the diffusion and attachment of W and Se on the edges of WSe2 on Au substrate. Ultrafast growth of high-quality uniform monolayer WSe2 is achieved by chemical vapor deposition using Au as a reusable substrate. The growth rate is ≈2–3 orders of magnitude faster than those reported due to the small energy barriers and exothermic characteristic, and the materials show excellent crystal quality and extraordinary electrical properties comparable to those of exfoliated samples.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adma.201700990