Direct CVD Synthesis of MoS2 Monolayers on Glass by Carbothermal Reduction

Chemical vapor deposition (CVD) synthesis for two-dimensional (2D) transition-metal dichalcogenides (TMDCs) is fundamentally important for realizing high-quality single crystals of TMDCs for future electronic and optoelectronic device applications. However, CVD synthesis of TMDCs generally requires a high synthetic temperature (>700 degrees C), which limits the choice of growth substrates and their broad applications. In this work, we present direct CVD synthesis of 2D MoS2 on glass. The CVD growth temperature was significantly decreased to 500 degrees C by employing carbothermal reduction, which uses carbon as the catalyst for reducing the thermal decomposition temperature of MoO3 precursors. MoS2 single crystals grown on glass showed no observable degradation in electrical, optical, and structural properties compared to MoS2 grown at high temperatures. The MoS2 grown on glass exhibited field effect mobility around 7.6 cm2 V-1 s-1 and a high ON/OFF ratio of up to 107, photoresponsivity up to 40 A/W, and stable and repeatable photocurrent. These findings demonstrate a promising strategy in the CVD growth of 2D materials and the design of their flexible and transparent devices.