Synthesis of monolayer MoS₂ via chemical vapor deposition

Abstract

Two-dimensional materials, specifically transition metal dichalcogenides (TMDs), have emerged as ideal candidates for lightweight and flexible optoelectronic applications. Unlike bulk solids, single layer TMDs exhibit a direct bandgap that makes next-generation device applications possible. This work describes the synthesis of single layer MoS2 via chemical vapor deposition (CVD). This method involves thermal vaporization of MoO3 and S precursors in a tube furnace. The influence of reaction conditions (e.g., temperature, pressure, reaction holding time, carrier gas flow rate, and precursor separation distance) on MoS2 sample morphology was quantified using optical microscopy. Isolated equilateral triangles with 11 μm-long edge lengths were reproducibly grown on Si/SiO2 substrates. The layer thickness was determined using Raman and photoluminescence spectroscopy.