Wafer‐Scale Growth of Monolayer MoSe ₂ via Salt‐Assisted Chemical Vapor Deposition

2D transition metal dichalcogenide (TMDs) of monolayer molybdenum diselenide (MoSe₂) is an emerging semiconductor for next-generation electronics, owing to its remarkable physical and electronic properties. The realization of diverse device applications depends critically on the scalable synthesis of high-quality monolayer MoSe₂ crystals, which remains challenging. In this study, the successful epitaxy of monolayer MoSe₂ films is demonstrated on sapphire substrates at a maximum wafer size of 2 inches via a salt-assisted chemical vapor deposition (SA-CVD) technique. A clean, rapid, and complete transfer process assisted by deionized water only has also been developed for the transfer of as-grown monolayer MoSe₂ films onto the target substrates. Field-effect transistors (FETs) fabricated from these monolayer MoSe₂ films exhibited an impressive mobility of 39.1 cm²V^-1s^-1 and an on/off current ratio ranging from 10⁸ to 10¹⁰. These results underscore an effective and scalable strategy for the synthesis of high-quality TMDCs, paving the way for their integration into advanced electronic applications.