NaCl-Assisted Chemical Vapor Deposition of Large-Domain Bilayer MoS₂ on Soda-Lime Glass

In recent years, two-dimensional molybdenum disulfide (MoS₂) has attracted extensive attention in the application field of next-generation electronics. Compared with single-layer MoS₂, bilayer MoS₂ has higher carrier mobility and has more promising applications for future novel electronic devices. Nevertheless, the large-scale low-cost synthesis of high-quality bilayer MoS₂ still has much room for exploration, requiring further research. In this study, bilayer MoS₂ crystals grown on soda-lime glass substrate by sodium chloride (NaCl)-assisted chemical vapor deposition (CVD) were reported, the growth mechanism of NaCl in CVD of bilayer MoS₂ was analyzed, and the effects of molybdenum trioxide (Mo) mass and growth pressure on the growth of bilayer MoS₂ under the assistance of NaCl were further explored. Through characterization with an optical microscope, atomic force microscopy and Raman analyzer, the domain size of bilayer MoS₂ prepared by NaCl-assisted CVD was shown to reach 214 μm, which is a 4.2X improvement of the domain size of bilayer MoS₂ prepared without NaCl-assisted CVD. Moreover, the bilayer structure accounted for about 85%, which is a 2.1X improvement of bilayer MoS₂ prepared without NaCl-assisted CVD. This study provides a meaningful method for the growth of high-quality bilayer MoS₂, and promotes the large-scale and low-cost applications of CVD MoS₂.