Titania-doped quartz glass and making method
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsShigeru Maida, Hisatoshi Otsuka, Osamu Sekizawa, Naoki Yanagisawa
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Abstract
A titania-doped quartz glass suited as an EUV lithographic member is prepared by feeding a silicon-providing reactant gas and a titanium-providing reactant gas through a burner along with hydrogen and oxygen, subjecting the reactant gases to oxidation or flame hydrolysis to form synthetic silica-titania fine particles, depositing the particles on a rotating target, and concurrently melting and vitrifying the deposited particles to grow an ingot of titania-doped quartz glass. The target is retracted such that the growth front of the ingot may be spaced a distance of at least 250 mm from the burner tip.
Claims15
A method for preparing a titania-doped quartz glass, comprising the steps of feeding a silicon-providing reactant gas and a titanium-providing reactant gas through a burner tip along with a combustible gas and a combustion-supporting gas, subjecting the reactant gases to oxidation or flame hydrolysis to form synthetic silica-titania fine particles, depositing the silica-titania fine particles on a rotating target, and concurrently melting and vitrifying the deposited particles to grow an ingot of titania-doped quartz glass,
- the method further comprising the step of retracting the target at such a rate that the distance between the burner tip and the growth front of the ingot is at least 250 mm.
A titania-doped quartz glass having an absorption edge wavelength at an apparent transmittance per 5-mm thickness, a distribution of the absorption edge wavelength being less than or equal to 10 nm.
Dependencies are inferred from the claim text.