Effect of precursor on growth and morphology of MoS2 monolayer and multilayer

The rise of two-dimensional (2D) material is one of the results of successful efforts of researchers which laid the path to the new era of electronics. One of the most exciting materials is MoS₂. Synthesis has been always a major issue as electronic devices need reproducibility along with similar properties for mass productions. Chemical vapor deposition (CVD) is one of the successful methods for 2D materials including graphene. Furthermore, the choice of starting materials for Mo and S source is crucial. The different source has different effects on the layers and morphology of MoS₂ films. In this work, we have extensively studied the CVD technique to grow few layers of MoS₂ with two precursors MoO₃ and MoCl₅, show remarkable changes. The MoO₃ source gives a triangular shaped MoS₂ monolayer while that of MoCl₅ can achieve uniform MoS₂ without triangle. The absence of geometric shapes with MoCl₅ is poorly understood. We tried to explain with MoCl₅ precursor, the formation of continuous monolayer of MoS₂ without any triangle on the basis of chemical reaction formalism mostly due to one step reaction process and formation of MoS₂ from gas phase to the solid phase. The film synthesized by MoCl₅ is more continuous and it would be a good choice for device applications.