Abstract
Transition metal dichalcogenide, TMDC, has been researched in recent years and got great progress in digit、analogy、microwave、optical、flexible devices, and large-area growth is the basis of all above. While CVD can grow large-area films now, but they are polycrystalline films with many boundaries, and these boundaries affect carrier transport a lot. In this thesis, we introduce NaCl as catalysts successfully enlarge single crystal WSe2 to exceeding 50 μm. In the other hand, we use MOCVD to precisely control precursor flow and expecting to grow less-defect, large-area monolayer MoS2 film. In the end, due to electron beam related instruments have been used in many research, and some papers have revealed that high energy electron beam will interact with samples. So, we do some analysis about how electron beam lithography system affect single crystal WSe2.