Cambridge NanoTech Inc.

UV BLOCKING

Double layer CeO2-TiO2 coatings are typically used for UV blocking applications, e.g. in automobile windshield applications. In this example, 160 nm thick UV absorbing coatings consisting of a complex oxide of cerium and titanium were deposited on glass via the sol-gel process. Addition of TiO2 to CeO2 changed the crystallinity and coordination state of CeO2 and improved UV absorption. Formation of a double-layered coating comprised of outer CeO2-TiO2 layer and inner TiO2-SiO2 layer diminished the interference coloring and improved the adhesion of the coating to the glass substrate. The double layer coated glass shows high UV-shielding properties without visible light absorption and excellent durability against chemical and physical attacks. Since both CeO2 and TiO2 are easily deposited by ALD, we suggest that this is explored. Improved properties can be expected due to the amorphous and homogeneous structure of ALD oxides, zero porosity, low stress, no baking needed and thus no shrinkage, excellent adhesion and with ALD less waste is produced compared to sol-gel based liquid processing.