Large-area MoS2 deposition via MOVPE

The direct deposition of the 2D transition metal dichalcogenide MoS2 via metal-organic vapour phase epitaxy (MOVPE) is investigated. Growth is performed in a commercial AIXTRON horizontal hot-wall reactor. Molybdenum hexacarbonyl (MCO) and Di-tert-butyl sulfide (DTBS) are used as metal-organic precursors for molybdenum and sulfur, respectively. The successful deposition of MoS2 is demonstrated via Raman spectroscopy on various substrates such as sapphire and Si as well as AIN and GaN templates. The influence of growth time on the evolution of layer morphology is investigated. Variation of carrier gas reveals that a pure nitrogen growth atmosphere and a growth temperature of 750 degrees C improve layer quality. Additionally, a post-deposition annealing process of the grown samples is examined. It is shown that annealing in a pure nitrogen atmosphere at temperatures between 650 degrees C and 750 degrees C strongly increases the Raman intensities.