Controlled synthesis and optical properties of polycrystalline molybdenum disulfide atomic layers grown by chemical vapor deposition

Abstract

We report a scalable growth of mono to few-layer molybdenum disulfide (MoS2) atomic layers on different substrates by chemical vapor deposition (CVD). The effects of the source material (sulfur and MoO3 powder) and the growth temperature were systematically optimized for the growth of both highly crystalline and large area MoS2. The deposited film thickness could be precisely controlled by varying the growth temperatures, and this was confirmed by Raman and AFM results. The monolayer, bilayer, and multilayer MoS2 could be obtained at 650 °C, 700 °C, and 750–800 °C, respectively. The mobility value of ∼0.89 cm2/V s and current on/off ratio in the order of ∼104 was estimated for monolayer MoS2. The mobility value increased to ∼7.6 cm2/V s for the bilayer MoS2. Our results pave the way for the controlled synthesis of high-quality transition metal dichalcogenide materials, which are an attractive option for applications in electronic and optoelectronic devices.