Data for Impact of co-reactants in atomic layer deposition of high-κ dielectrics on monolayer molybdenum disulfide

Traditional thermal atomic layer deposition (ALD) is commonly used to deposit dielectrics on three-dimensional substrates, but ALD of high-κ materials on monolayer TMDCs is more challenging. Thermal ALD with water (H2O) co-reactant often results in incomplete and nonuniform dielectric growth on atomically thin TMDCs, owing to a chemically inert basal plane.

The development of alternative ALD processes for the realization of dielectric layers on monolayer TMDCs is therefore important. Here, we study oxygen (O2) plasma and ozone (O3) as co-reactants for the ALD of aluminum oxide (Al2O3) and hafnium dioxide (HfO2) on monolayer molybdenum disulfide (1L MoS2) films. By employing a robust characterization process that combines atomic force microscopy, Raman/photoluminescence spectroscopy, and X-ray photoelectron spectroscopy, we reveal growth of high-κ dielectrics by plasma-enhanced ALD with O2 plasma oxidant damages the underlying 1L MoS2 via oxidation to molybdenum trioxide (MoO3).