Controlled Synthesis of Highly Crystalline MoS_2 Flakes by Chemical Vapor Deposition

摘要

The controlled synthesis of highly crystalline MoS_2 atomic layers remains a challenge for the practical applications of this emerging material. Here, we developed an approach for synthesizing MoS_2 flakes in rhomboid shape with controlled number of layers by the layer-by-layer sulfurization of MoO_2 microcrystals. The obtained MoS_2 flakes showed high crystallinity with crystal domain size of ～10 μm, significantly larger than the grain size of MoS_2 grown by other methods. As a result of the high crystallinity, the performance of back-gated field effect transistors (FETs) made on these MoS_2 flakes was comparable to that of FETs based on mechanically exfoliated flakes. This simple approach opens up a new avenue for controlled synthesis of MoS_2 atomic layers and will make this highly crystalline material easily accessible for fundamental aspects and various applications.