Chemical Vapor Deposition of Uniform and Large-Domain Molybdenum Disulfide Crystals on Glass/Al 2 O 3 Substrates.

Two-dimensional molybdenum disulfide (MoS 2 ) has attracted significant attention for next-generation electronics, flexible devices, and optical applications. Chemical vapor deposition is the most promising route for the production of large-scale, high-quality MoS 2 films. Recently, the chemical vapor deposition of MoS 2 films on soda-lime glass has attracted great attention due to its low cost, fast growth, and large domain size. Typically, a piece of Mo foil or graphite needs to be used as a buffer layer between the glass substrates and the CVD system to prevent the glass substrates from being fragmented. In this study, a novel method was developed for synthesizing MoS 2 on glass substrates. Inert Al 2 O 3 was used as the buffer layer and high-quality, uniform, triangular monolayer MoS 2 crystals with domain sizes larger than 400 μm were obtained. To demonstrate the advantages of glass/Al 2 O 3 substrates, a direct comparison of CVD MoS 2 on glass/Mo and glass/Al 2 O 3 substrates was performed. When Mo foil was used as the buffer layer, serried small bilayer islands and bright core centers could be observed on the MoS 2 domains at the center and edges of glass substrates. As a control, uniform MoS 2 crystals were obtained when Al 2 O 3 was used as the buffer layer, both at the center and the edge of glass substrates. Raman and PL spectra were further characterized to show the merit of glass/Al 2 O 3 substrates. In addition, the thickness of MoS 2 domains was confirmed by an atomic force microscope and the uniformity of MoS 2 domains was verified by Raman mapping. This work provides a novel method for CVD MoS 2 growth on soda-lime glass and is helpful in realizing commercial applications of MoS 2 .