Doped silica-titania glass having low expansivity and methods of making the same

Patent metadata

Field	Value
Publication number	US-2016145147-A1
Application number	US-201514950374-A
Country	US
Kind code	A1
Filing date	Nov 24, 2015
Priority date	Nov 26, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

A method of forming a doped silica-titania glass is provided. The method includes blending batch materials comprising silica, titania, and at least one dopant. The method also includes heating the batch materials to form a glass melt. The method further includes consolidating the glass melt to form a glass article, and annealing the glass article.

First claim

What is claimed is:

1 . A method of forming a doped silica-titania glass, the method comprising:
blending batch materials comprising silica, titania, and at least one dopant; heating the batch materials to form a glass melt; consolidating the glass melt to form a glass article; and annealing the glass article.

2 . The method of claim 1 , wherein the at least one dopant is selected from the group consisting of chlorine, fluorine, and oxides containing boron, niobium, tantalum, aluminum, manganese, lithium, sodium, potassium, calcium, arsenic, antimony, tin, copper, zirconium, germanium and magnesium, and combinations thereof.

3 . The method of claim 1 , wherein blending the batch materials comprises forming a slurry in the presence of a liquid.

4 . The method of claim 1 , further comprising doping the glass melt with fluorine by contacting the glass melt with a fluorine precursor gas.

5 . The method of claim 4 , wherein the fluorine precursor is selected from the group consisting of F 2 , C 2 F 6 , CF 4 , SF 6 , SiF 4 and combinations thereof.

6 . The method of claim 1 , further comprising heating the glass article to form a glass article substantially free of crystalline material.

7 . The method of claim 1 , comprising consolidating the glass melt under vacuum.

8 . The method of claim 1 , wherein consolidating the glass melt comprises exposing the glass melt to a steam-containing atmosphere.

9 . The method of claim 1 , wherein annealing the glass article comprises holding the glass article at a temperature between about 600° C. and about 1000° C.

10 . The method of claim 1 , wherein annealing the glass article comprises cooling the glass article at a rate of less than about 10° C. per hour.

11 . A doped silica-titania glass formed by batch melting, the glass comprising:
between about 75 wt. % and about 91 wt. % silica; between about 9.0 wt % and about 17 wt. % titania; and between about 0.001 wt. % and about 10 wt. % of at least one dopant.

12 . The doped silica-titania glass of claim 11 , wherein the at least one dopant comprises boron oxide.

13 . The doped silica-titania glass of claim 12 , comprising between about 0.50 wt. % and about 5.0 wt. % boron oxide.

14 . The doped silica-titania glass of claim 11 , wherein the at least one dopant comprises fluorine.

15 . The doped silica-titania glass of claim 14 , comprising between about 0.001 wt. % and about 2.0 wt. % fluorine.

16 . An optical element for photolithography, the optical element comprising a doped silica-titania glass formed by batch melting, the glass comprising:
between about 75 wt. % and about 91 wt. % silica; between about 9.0 wt % and about 17 wt. % titania; and between about 0.001 wt. % and about 10 wt. % of at least one dopant.

17 . The optical element of claim 16 , wherein the at least one dopant comprises boron oxide.

18 . The optical element of claim 17 , comprising between about 0.50 wt. % and about 5.0 wt. % boron oxide.

19 . The optical element of claim 16 , wherein the at least one dopant comprises fluorine.

20 . The optical element of claim 19 , comprising between about 0.001 wt. % and about 2.0 wt. % fluorine.

Assignees

• Corning Inc

Inventors

• Annamalai Sezhian
• Duran Carlos Alberto
• Hrdina Kenneth Edward
• Moore Lisa Anne

Classifications

• C03B2201/12

  doped with fluorine (C03B2201/14 takes precedence) · CPC title

• C03C3/112 Primary

  containing fluorine · CPC title

• C03C3/06

  with more than 90% silica by weight, e.g. quartz {(C03C3/045 takes precedence)} · CPC title

• G03F1/22

  Masks or mask blanks for imaging by radiation of 100nm or shorter wavelength, e.g. X-ray masks, extreme ultraviolet [EUV] masks; Preparation thereof · CPC title

• C03C3/089

  containing boron · CPC title