SILICA GLASS CONTAINING TIO2 AND OPTICAL MATERIAL FOR EUV LITHOGRAPHY

摘要

A silica glass containing TiO2, characterized in that the fluctuation of the refractive index (Deltan) is at most 2 ~10<-4> within an area of 30 mm ~ 30 mm in at least one plane. A silica glass containing TiO2, characterized in that the TiO2 concentration is at least 1 mass%, and the striae pitch is at most 10 µm. An optical material for EUV lithography, characterized in that it is made of a silica glass containing TiO2, and the fluctuation of the refractive index (Deltan) is at most 2 ~10<-4> in a plane perpendicular to the incident light direction. An optical material for EUV lithography, characterized in that it is made of a silica glass containing TiO2, wherein the TiO2 concentration is at least 1 mass%, and the difference between the maximum value and the minimum value of the TiO2 concentration is at most 0.06 mass% in a plane perpendicular to the incident light direction.