Domain Aligned Growth of Molybdenum Disulfide on Various Substrates by Chemical Vapor Deposition

We synthesized single-layer MoS2 atomic films on various substrates by a chemical vapor deposition method. We chose three different substrates for MoS2 synthesis in this study; SiO2 as an amorphous substrate, Al2O3 or GaN as hexagonal crystalline substrates. The lattice constant of Al2O3 is not well matched with that of MoS2 whereas the lattice constant for GaN is well matched with that of MoS2. We investigated the orientation properties of the domains of single-layer MoS2 atomic films on these three substrates and found that MoS2 domains synthesized on lattice-matched GaN substrate are aligned better than the other MoS2 domains synthesized on SiO2 or Al2O3 substrates. Our study may provide an insight as a route to synthesize large size, single-layer, and single-domain MoS2 atomic films.