Large-area synthesis of high-quality and uniform monolayer WS2 on reusable Au foils

• Published in: Nature communications Vol. 6; no. 1; p. 8569
• Main Authors: Gao, Yang, Liu, Zhibo, Sun, Dong-Ming, Huang, Le, Ma, Lai-Peng, Yin, Li-Chang, Ma, Teng, Zhang, Zhiyong, Ma, Xiu-Liang, Peng, Lian-Mao, Cheng, Hui-Ming, Ren, Wencai
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.10.2015; Nature Publishing Group; Nature Pub. Group
• Subjects: 119/118; 140/133; 140/146; 142/126; 639/301/357/1018; 639/925/357/551; Crystals; Electrical properties; Electrochemistry; Fabrication; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms9569

Large-area monolayer WS 2 is a desirable material for applications in next-generation electronics and optoelectronics. However, the chemical vapour deposition (CVD) with rigid and inert substrates for large-area sample growth suffers from a non-uniform number of layers, small domain size and many defects, and is not compatible with the fabrication process of flexible devices. Here we report the self-limited catalytic surface growth of uniform monolayer WS 2 single crystals of millimetre size and large-area films by ambient-pressure CVD on Au. The weak interaction between the WS 2 and Au enables the intact transfer of the monolayers to arbitrary substrates using the electrochemical bubbling method without sacrificing Au. The WS 2 shows high crystal quality and optical and electrical properties comparable or superior to mechanically exfoliated samples. We also demonstrate the roll-to-roll/bubbling production of large-area flexible films of uniform monolayer, double-layer WS 2 and WS 2 /graphene heterostructures, and batch fabrication of large-area flexible monolayer WS 2 film transistor arrays. WS 2 is a promising material for application in next-generation electronics, yet current methods of fabrication can only yield micrometre-sized domains. Here, via ambient-pressure CVD, the authors report the growth of high-quality, uniform monolayer WS 2 single crystals of the order of millimetres.