It is to provide a silica glass containing TiO2, having a wide temperature range wherein the coefficient of thermal expansion is substantially zero.
A silica glass containing TiO2, which has a TiO2 concentration of from 3 to 10 mass %, a OH group concentration of at most 600 mass ppm and a Ti3+ concentration of at most 70 mass ppm, characterized by having a fictive temperature of at most 1,200° C., a coefficient of thermal expansion from 0 to 100° C. of 0±150 ppb/° C., and an internal transmittance T400-700 per 1 mm thickness in a wavelength range of from 400 to 700 nm of at least 80%. A process for producing a silica glass containing TiO2, which comprises porous glass body formation step, F-doping step, oxygen treatment step, densification step and vitrification step.