The effect of Ar plasma on the space-confined growth of MoS2 with low-pressure chemical vapor deposition

Plasma assisted low-pressure chemical vapor deposition has previously been shown to allow for large area growth of a variety of 2D materials, such as graphene and boron nitride. However, it also presented with degradation of electronic properties owing to decreases in grain sizes and increased inclusion of defects. In this work, we report on the influence of an Ar plasma during the growth of MoS2. We produce hexagonal and triangular single crystal 2D MoS2 with sizes up to 10 µm, similar to that achieved without plasma present. Raman analysis also exhibits no significant changes with plasma. However, the plasma does induce changes to the morphology of the MoS2 crystals, leading to non-uniform edge structures with the degree of non-uniformity scaling with plasma power. Comparing the overall morphology at different temperatures and amounts of precursor material suggests that plasma increases the availability of Mo for growth, which is further evidenced by increased growth zones. Therefore, the use of an Ar plasma may provide a means to reduce required precursor quantities without significantly compromising the overall structure of the resulting MoS2 crystals.