OPTICAL SYNTHETIC QUARTZ GLASS, ITS PRODUCTION AND OPTICAL MEMBER FOR EXCIMER LASER

摘要

PROBLEM TO BE SOLVED: To provide an optical synthetic quartz glass excellent in light transmittance, optical homogeneity and optical stability and highly resistant to a laser, its production method and an optical member for an excimer laser. SOLUTION: The synthetic quartz glass is formed by directly vitrifying the silica fine particle obtained by the flame hydrolysis of an organodisilazane compd. on a preform, and its birefringence is controlled to <=5 nm/cm and the refractive index difference (Δn) to <=2×10<-6> . The synthetic quartz glass is produced by introducing an organodisilazane compd. expressed, by (R<1> )3 SiNHSi(R<2> )3 into a flame 2 consisting of a combustion gas and a combustion supporting gas, depositing the formed silica fine particle on the rotating heat- resistant preform 1, melting and vitrifying the particle. In the formula, R<1> and R<2> are hydrogen and 1-3C univalent aliphatic hydrocarbonic groups which can be the same or different. The optical member for an excimer laser is produced from the synthetic quartz glass.