Two-dimensional (2D) nanomaterials have shown unique electrical and chemical characteristics essential for the enhancement of electronic and optoelectronic devices. Large-area fabrication of 2D materials like MoS₂ is challenging due to poor nucleation and vertical multilayer growth. In this study, we employed wafer-scale CVD with gaseous precursors for MoS₂ to facilitate large-area deposition and utilized NaCl to assist nucleation control. Precise control of the nucleation with NaCl has significantly increased the grain size of MoS₂ from about 1–2 nm to 300 nm. However, a phase shift in MoS₂ thin films from semiconductive 2H to metallic 1T phase was observed due to the Na intercalation. As a result, a shift in lower binding energy occurs in XPS analysis. Our findings contribute to the comprehension of phase transition phenomena in MoS₂ thin films and further advancement in the synthesis techniques of MoS₂ thin films within wafer-scale deposition environments.

https://www.sciencedirect.com/science/article/pii/S0167577X24003318