View article

We investigate the ability of different carrier gases to control defects and secondary nucleation in atmospheric pressure chemical vapor deposition (APCVD) growth of MoS₂ on Si/SiO₂ substrates. We observe that a reducing environment using H₂ gas is more favorable for achieving uniform two-dimensional (2D) growth. Compared to the growth in an inert environment, secondary nucleation on primary MoS₂ domains grown using H₂ as the carrier gas (H–MoS₂) is drastically reduced. We employ a phase-field model to understand the role of enhanced surface diffusion in H–MoS₂, due to passivation of defects and dangling bonds, promoting compact secondary domain formation as opposed to dendritic secondary domains under an inert environment. Using X-ray photoelectron spectroscopy, we show that the Mo(VI) oxidation state (corresponding to MoO₃), which is prominent for MoS₂ grown under an inert …