DIELECTRIC FILM HAVING HIGH REFRACTIVE INDEX AND METHOD FOR PREPARATION THEREOF

摘要

A dielectric film having a high refractive index, characterized in that it comprises an amorphous material comprising a titanium oxide (TiOx wherein 1≤x≤2) as a primary component and another metal oxide (MOw wherein M is a metal such as niobium or tantalum and 1≤w) as an additive component and having no cylindrical structure. Although a titanium oxide is prone to crystallize even in a thin film form, the above dielectric film takes an amorphous state since the above another metal oxide added interferes with the crystal growth of a titanium oxide. The dielectric film has a high refractive index, exhibits the reduced change over time of optical characteristics, and has a reduced film stress, and thus it can be used with stability as a constituent material of an optical multilayer film.