Characterization of sputter-deposited ZrBxOy films

ZrBxOy films for optical durable coating application were deposited by reactive dc magnetron sputtering of Zr--B alloy target on soda-lime-silica glass substrate without intentional heating. Effect of boron content on film properties was investigated. The refractive index of the film was decreased from 2.1 to 1.69 corresponding to the increase of B2O3 content from 0 to 64 mol %. The films containing more than 13 mol % B2O3 fraction were amorphous and showed remarkably improved mechanical durability compared with ZrO2 film. More than 51 mol % B2O3 content resulted in degrading of chemical durability. Measurement of mechanical properties was carried out together with characterization on crystalline structure and chemical binding state