Thermal and Plasma-Enhanced Atomic Layer Deposition of Yttrium Oxide Films and the Properties of Water Wettability

摘要

The atomic layer deposition (ALD) of yttrium oxide (Y2O3) is investigated using the liquid precursor Y(EtCp)(2)(iPr-amd) as the yttrium source with thermal (H2O) and plasma-enhanced (H2O plasma and O-2 plasma) processes, respectively. Saturation is confirmed for the growth of the Y2O3 films with each investigated reactant with a similar ALD window from 150 to 300 degrees C, albeit with a different growth rate. All of the as-deposited Y2O3 films are pure and smooth and have a polycrystalline cubic structure. The as-deposited Y2O3 films are hydrophobic with water contact angles >90 degrees. The water contact angle gradually increased and the surface free energy gradually decreased as the film thickness increased, reaching a saturated value at a Y2O3 film thickness of similar to 20 nm. The hydrophobicity was retained during post-ALD annealed at 500 degrees C in static air for 2 h. Exposure to polar and nonpolar solvents influences the Y2O3 water contact angle. The reported ALD process for Y2O3 films may find potential applications in the field of hydrophobic coatings.