METHOD FOR PRODUCING TIO2-SIO2 GLASS BODY, METHOD FOR HEAT-TREATING TIO2-SIO2 GLASS BODY, TIO2-SIO2 GLASS BODY, AND OPTICAL BASE FOR EUVL

摘要

The present invention relates to a process for production of a TiO2—SiO2 glass body, comprising a step of, when an annealing point of a TiO2—SiO2 glass body after transparent vitrification is taken as T1(° C.), holding the glass body after transparent vitrification in a temperature region of from T1−90(° C.) to T1−220(° C.) for 120 hours or more.