Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: A method of forming a glass article is provided. The method includes the steps of positioning a first interface surface of a first glass block proximate a second interface surface of a second glass block to define an interface seam, welding the first and second glass blocks together around a majority of the interface seam to define an internal cavity, coupling a vacuum fitting to at least one of the first and second glass blocks, drawing a vacuum in the cavity between the first and second glass blocks, and heating the first and second glass blocks to fuse the first and second glass blocks together.

Abstract: Near-infrared shielding includes a glass material. The shielding provides transmittance at wavelengths between 390 to 700 nm, but near infrared absorbing species are distributed throughout the glass material and the shielding blocks light in the near infrared range. Further, the glass material has a near zero or negative coefficient of thermal expansion, allowing the glass material to heat up when the shielding is blocking a near infrared laser, without expanding much.

Abstract: A glass composite for use in Extreme Ultra-Violet Lithography (EUVL) is provided. The glass composite includes a first silica-titania glass section. The glass composite further includes a second doped silica-titania glass section mechanically bonded to a surface of the first silica-titania glass section, wherein the second doped silica-titania glass section has a thickness of greater than about 1.0 inch.

Abstract: A process for manufacturing glass articles from powder at low temperatures includes the steps of preparing a slurry of powder suspended in a liquid; depositing the slurry on a substrate; drying the slurry to form a layer on the substrate; depositing slurry on the layer; drying the slurry deposited on the layer on the substrate to form another layer; repeating the steps of depositing a slurry and drying the to form a plurality of sequential layers on the substrate; and consolidating the plurality of sequential layers to form a glass article. The process requires a small manufacturing footprint, and facilitates the manufacture of very large near-net shape glass articles.

Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: Near-infrared shielding includes a glass material. The shielding provides transmittance at wavelengths between 390 to 700 nm, but near infrared absorbing species are distributed throughout the glass material and the shielding blocks light in the near infrared range. Further, the glass material has a near zero or negative coefficient of thermal expansion, allowing the glass material to heat up when the shielding is blocking a near infrared laser, without expanding much.

Abstract: A method of forming a glass article is provided. The method includes the steps of positioning a first interface surface of a first glass block proximate a second interface surface of a second glass block to define an interface seam, welding the first and second glass blocks together around a majority of the interface seam to define an internal cavity, coupling a vacuum fitting to at least one of the first and second glass blocks, drawing a vacuum in the cavity between the first and second glass blocks, and heating the first and second glass blocks to fuse the first and second glass blocks together.

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.

Abstract: A glass composite for use in Extreme Ultra-Violet Lithography (EUVL) is provided. The glass composite includes a first silica-titania glass section. The glass composite further includes a second doped silica-titania glass section mechanically bonded to a surface of the first silica-titania glass section, wherein the second doped silica-titania glass section has a thickness of greater than about 1.0 inch.

Abstract: A doped silica-titania (“DST”) glass article that includes a glass article having a glass composition comprising a silica-titania base glass containing titania at 7 to 14 wt. % and a balance of silica, and a dopant selected from the group consisting of (a) F at 0.7 to 1.5 wt. %, (b) B2O3 at 1.5 to 5 wt. %, (c) OH at 1000 to 3000 ppm, and (d) B2O3 at 0.5 to 2.5 wt. % and OH at 100 to 1400 ppm. The glass article has an expansivity slope of less than about 1.3 ppb/K2 at 20° C. For DST glass articles doped with F or B2O3, the OH level can be held to less than 10 ppm, or less than 100 ppm, respectively. In many aspects, the DST glass articles are substantially free of titania in crystalline form.

Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: A doped silica-titania (“DST”) glass article that includes a glass article having a glass composition comprising a silica-titania base glass containing titania at 7 to 14 wt. % and a balance of silica, and a dopant selected from the group consisting of (a) F at 0.7 to 1.5 wt. %, (b) B2O3 at 1.5 to 5 wt. %, (c) OH at 1000 to 3000 ppm, and (d) B2O3 at 0.5 to 2.5 wt. % and OH at 100 to 1400 ppm. The glass article has an expansivity slope of less than about 1.3 ppb/K2 at 20° C. For DST glass articles doped with F or B2O3, the OH level can be held to less than 10 ppm, or less than 100 ppm, respectively. In many aspects, the DST glass articles are substantially free of titania in crystalline form.

Abstract: A doped silica-titania glass article is provided that includes a glass article having a glass composition comprising (i) a silica-titania base glass, (ii) a fluorine dopant, and (iii) a second dopant. The fluorine dopant has a concentration of fluorine of up to 5 wt. % and the second dopant comprises one or more oxides selected from the group consisting of Al, Nb, Ta, B, Na, K, Mg, Ca and Li oxides at a total oxide concentration from 50 ppm to 6 wt. %. Further, the glass article has an expansivity slope of less than 0.5 ppb/K2 at 20° C. The second dopant can be optional. The composition of the glass article may also contain an OH concentration of less than 100 ppm.

Abstract: Ultralow expansion titania-silica glass. The glass has high hydroxyl content and optionally include one or more dopants. Representative optional dopants include boron, alkali elements, alkaline earth elements or metals such as Nb, Ta, Al, Mn, Sn Cu and Sn. The glass is prepared by a process that includes steam consolidation to increase the hydroxyl content. The high hydroxyl content or combination of dopant(s) and high hydroxyl content lowers the fictive temperature of the glass to provide a glass having a very low coefficient of thermal expansion (CTE), low fictive temperature (Tf), and low expansivity slope.

Abstract: Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

Abstract: A glass article for use in Extreme Ultra-Violet Lithography (EUVL) is provided. The glass article includes a silica-titania glass having a compositional gradient through the glass article, the compositional gradient being defined by the functions: [TiO2]=(c+f(x,y,z)), and [SiO2]=(100?{c+f(x,y,z)}??(x,y,z)) wherein [TiO2] is the concentration of titania in wt. %, [SiO2] is the concentration of silica in wt. %, c is the titania concentration in wt. % for a predetermined zero crossover temperature (Tzc), f(x, y, z) is a function in three-dimensional space that defines the difference in average composition of a volume element centered at the coordinates (x, y, z) with respect to c, and ?(x, y, z) is a function in three-dimensional space that defines the sum of all other components of a volume element centered at the coordinates (x, y, z).

Abstract: A boron-doped titania-silica glass containing 0.1 wt % to 8.0 wt % boron, 9.0 wt % to 16.0 wt % TiO2, and 76.0 wt % to 90.9 wt % SiO2. The glass may further include F, Nb, Ta, Al, Li, Na, K, Ca, and Mg, individually or in combinations of two or more, at levels up to 4 wt %. The glass may have an OH concentration of more than 10 ppm. The glass features a CTE slope at 20° C. of less than 1 ppb/K2. The fictive temperature of the glass is less than 825° C. and the peak CTE of the glass is less than 30 ppb/K. The glass has two crossover temperatures and a wide temperature interval over which CTE is close to zero. The uniformity of each crossover temperature relative to its average over a volume of at least 50 cm3 is within ±5° C.