Transparent and water repellent ceria film grown by atomic layer deposition

Transparent and hydrophobic ceria film was fabricated by atomic layer deposition (ALD). The ceria coatings were characterized by goniometry, atomic force microscopy, X-ray photoelectron spectroscopy and variable angles spectroscopic ellipsometry. The hydrophobicity of the ceria coatings was investigated with water contact angles achieving as high as 105°. The effect of annealing or surface relaxation on the hydrophobicity was studied. Surface chemistry analysis of the ceria surfaces was carried out to understand the surface treatment towards the wettability of the ALD coatings. The proposed ALD ceria film offers the advantages of hydrophobic coatings covering fine optical lens such as band-pass filter.