Abstract: This disclosure is directed to a silica-titania-niobia glass and to a method for making the glass. The composition of the silica-titania-niobia (SiO2—TiO2—Nb2O5) glass, determined as the oxides, is Nb2O5 in an amount in the range of 0.005 wt. % to 1.2 wt. %, TiO2 in an amount in the range of 5 wt. % to 10 wt. %, and the remainder of glass is SiO2. In the method, the STN glass precursor is consolidated into a glass by heating to a temperature of 1600° C. to 1700° C. in flowing helium for 6 hours to 10 hours. When this temperature is reached, the helium flow can be replaced by argon for the remainder of the time. Subsequently the glass is cooled to approximately 1050° C., and then from 1050° C. to 700° C. followed by turning off the furnace and cooling the glass to room temperature at the natural cooling rate of the furnace.

Abstract: An antireflection article including: a transparent substrate having a refractive index of from 1.48 to 1.53; a binder layer associated with the substrate, the binder having a refractive index of from 1.55 to 1.75; and a nanoparticulate monolayer or near monolayer associated with the binder layer, the nanoparticulate layer having an effective refractive index less than the refractive index of binder. Methods of making and using the article are also disclosed.

Abstract: A fused silica glass article having greater resistance to damage induced by exposure to laser radiation such as laser induced wavefront distortion at deep ultraviolet (DUV) wavelengths, and behaviors such as fluence dependent transmission, which are related to intrinsic defects in the glass. The improved resistance to laser damage may be achieved in some embodiments by loading the glass article with molecular hydrogen (H2) at temperatures of about 400° C. or less, or 350° C. or less. The combined OH and deuteroxyl (OD) concentration may be less than 10 ppm by weight. In other embodiments, the improved resistance may be achieved by providing the glass with 10 to 60 ppm deuteroxyl (OD) species by weight. In still other embodiments, improved resistance to such laser damage may be achieved by both loading the glass article with molecular hydrogen at temperatures of about 350° C. or less and providing the glass with less than 10 ppm combined OH and OD, or 10 to 60 ppm OD by weight.

Abstract: The present disclosure is directed to a doped silica-titania glass, DST glass, consisting essentially of 0.1 wt. % to 5 wt. % halogen, 50 ppm-wt. to 6 wt. % one or more oxides of Al, Ta and Nb, 3 wt. % to 10 wt. % TiO2 and the remainder SiO2. In an embodiment the halogen content can be in the range of 0.2 wt. % to 3 wt. % along with 50 ppm-wt. to 6 wt. % one or more oxides of Al, Ta and Nb, 3 wt. % to 10 wt. % TiO2 and the remainder SiO2. In an embodiment the DST glass has an OH concentration of less than 100 ppm. In another embodiment the OH concentration is less than 50 ppm. The DST glass has a fictive temperature Tf of less than 875° C. In an embodiment Tf is less than 825° C. In another embodiment Tf is less than 775° C.

Abstract: The disclosure describes a silica-titania glass having a selected titania content in the range of 5-20 wt % that has zero crossover temperature (Tzc) associated with the selected titania content withing this range, and the Tzc is adjustable by ±10° C. or less. The disclosure also describes a method by which the Tzc of a silica-titania glass article, for example, a mirror substrate, can be tuned to within a specification range by means of a selected final anneal that shifts Tzc of the article or substrate to the desired Tzc value. In addition, since different mirrors in a set can be specified at different values of Tzc, this process the method can be on used glass samples or pieces from a single glass boule to make parts with different Tzc values, thus reducing the number of separate boules required to fill an order.

Abstract: The present disclosure is directed to a doped silica-titania glass, DST glass, consisting essentially of 0.1 wt. % to 5 wt. % halogen, 50 ppm-wt. to 6 wt. % one or more oxides of Al, Ta and Nb, 3 wt. % to 10 wt. % TiO2 and the remainder SiO2. In an embodiment the halogen content can be in the range of 0.2 wt. % to 3 wt. % along with 50 ppm-wt. to 6 wt. % one or more oxides of Al, Ta and Nb, 3 wt. % to 10 wt. % TiO2 and the remainder SiO2. In an embodiment the DST glass has an OH concentration of less than 100 ppm. In another embodiment the OH concentration is less than 50 ppm. The DST glass has a fictive temperature Tf of less than 875° C. In an embodiment Tf is less than 825° C. In another embodiment Tf is less than 775° C.

Abstract: The disclosure describes a method by which the Tzc of a silica-titania glass article, for example, a EUVL mirror substrate, can be tuned to within a specification range by means of a selected final anneal that shifts Tzc of the article or substrate to the desired Tzc value. In addition, since different mirrors in a set can be specified at different values of Tzc, this process can be on used glass samples or pieces from a single glass boule to make parts with different Tzc values, thus reducing the number of separate boules required to fill an order.

Abstract: This disclosure is directed to a silica-titania-niobia glass and to a method for making the glass. The composition of the silica-titania-niobia (SiO2—TiO2—Nb2O5) glass, determined as the oxides, is Nb2O5 in an amount in the range of 0.005 wt. % to 1.2 wt. %, TiO2 in an amount in the range of 5 wt. % to 10 wt. %, and the remainder of glass is SiO2. In the method, the STN glass precursor is consolidated into a glass by heating to a temperature of 1600° C. to 1700° C. in flowing helium for 6 hours to 10 hours. When this temperature is reached, the helium flow can be replaced by argon for the remainder of the time. Subsequently the glass is cooled to approximately 1050° C., and then from 1050° C. to 700° C. followed by turning off the furnace and cooling the glass to room temperature at the natural cooling rate of the furnace.

Abstract: A method of making a silica glass having a uniform fictive temperature. The glass article is heated at a target fictive temperature, or heated or cooled at a rate that is less than the rate of change of the fictive temperature, for a time that is sufficient to allow the fictive temperature of the glass to come within 3° C. of the target fictive temperature. The silica glass is then cooled from the target fictive temperature to a temperature below the strain point of the glass at a cooling rate that is greater than the relaxation rate of the glass at the target fictive temperature. The silica glass has a fictive temperature that varies by less than 3° C. after the annealing step. A silica glass made by the method is also described.

Abstract: In one embodiment the present disclosure is directed to a silica-titania glass with an internal transmission of >90%/cm at wavelengths from 340 nm to 840 nm. In another embodiment the internal transmission is >93%/cm at wavelengths from 340 nm to 840 nm. In a further embodiment the internal transmission is >95%/cm at wavelengths from 340 nm to 840 nm. In another embodiment the disclosure is directed to a silica-titania glass with an overall transmission through an optic made of the glass is >84% at wavelengths from 340 nm to 840 nm. In another embodiment overall transmission through an optic made of the glass is >86% at wavelengths from 340 nm to 840 nm. In a further embodiment the overall transmission through an optic made of the glass is >88% at wavelengths from 330 nm to 840 nm. In a further embodiment the silica-titania glass has a Ti+3 concentration level [Ti3+] less than 3 ppm by weight.

Abstract: Leaching alkali ions from a glass substrate to form a glass substrate having an intrinsic alkali barrier layer includes providing a glass substrate comprising alkali metal ions and having at least two opposing surfaces and a thickness between the surfaces, and contacting at least one of the surfaces of the substrate with a solution comprising alkaline earth salts in either water or as a melted salt bath such that at least a portion of the alkali metal ions are replaced by alkaline earth metal ions in the at least one surface and into the thickness to form the glass substrate having an intrinsic alkali barrier layer.

Abstract: The disclosure relates to vessels configured to contain molten semiconducting materials.

Abstract: A fused silica glass having a refractive index homogeneity of less or equal to about 5 ppm over an aperture area of at least about 50 cm2. The fused silica glass is also substantially free of halogens and has an adsorption edge of less than about 160 nm. The glass is dried by exposing a silica soot blank to carbon monoxide before consolidation, reducing the combined concentration of hydroxyl (i.e., OH, where H is protium (11H) and deuteroxyl (OD), where D is deuterium (12H)) of less than about 20 ppm by weight in one embodiment, less than about 5 ppm by weight in another embodiment, and less than about 1 ppm by weight in a third embodiment.

Abstract: A method of making a fused silica article that is loaded with hydrogen. A fused silica glass near net shape part is provided and is loaded with a molecular hydrogen in a range from about 0.1×1017 molecules/cm3 up to about 1×1019 molecules/cm3. The thinner shape of the near net shape part enables the shape to be loaded more quickly than previous methods. A fused silica article loaded with hydrogen using the method is also described.

Abstract: A fused silica glass article having a low absolute refractive index and low concentrations of hydroxyl groups, halogens, and metal having a low absolute refractive index. The glass article contains less than about 10 ppm protium-containing and deuterium-containing hydroxyl groups by weight and less than about 20 ppm halogens by weight. The silica glass article also has an absolute refractive index (ARI) less than or equal to 1.560820. In one embodiment, the ARI of the fused silica article is achieved by lowering the fictive temperature of the fused silica. A method of lowering the fictive temperature is also described.

Abstract: The present disclosure is directed to a method for producing constancy of the ion-exchanged product stress profile through adjustment of ion-exchange conditions by taking account of the influence of salt bath poisoning on the bath's useful lifetime. The present disclosure is directed to a method of ion-exchange in which the salt bath temperature and salt bath time are adjusted as a function of the amount of alkali metal ions that exchange in the bath. That is, temperature and time are adjusted as a function of salt bath poisoning. Temperature is set to its highest value and time to its shortest value in the starting unpoisoned salt bath, those values chosen to hit target values of surface compressive stress and exchange depth of layer. Temperature is then reduced and time lengthened as salt bath poisoning proceeds, those changes chosen to maintain the same surface compressive stress and exchange depth of layer.

Abstract: The present disclosure is directed to a method for producing constancy of the ion-exchanged product stress profile through adjustment of ion-exchange conditions by taking account of the influence of salt bath poisoning on the bath's useful lifetime. The present disclosure is directed to a method of ion-exchange in which the salt bath temperature and salt bath time are adjusted as a function of the amount of alkali metal ions that exchange in the bath. That is, temperature and time are adjusted as a function of salt bath poisoning. Temperature is set to its highest value and time to its shortest value in the starting un-poisoned salt bath, those values chosen to hit target values of surface compressive stress and exchange depth of layer. Temperature is then reduced and time lengthened as salt bath poisoning proceeds, those changes chosen to maintain the same surface compressive stress and exchange depth of layer.

Abstract: A method of chemically strengthening a glass article having an antireflective coating in which the reflectance of the coating is not significantly degraded by chemical strengthening. The glass article having the antireflective coating is strengthened using an ion exchange medium that comprises potassium nitrate and at least about 5 wt % potassium nitrite. Also provided are a glass article having an antireflective surface that is not degraded by such ion exchange and an ion exchange medium comprising potassium nitrate and at least about 5 wt % potassium nitrite.

Abstract: A method for producing a fused silica glass containing titania includes synthesizing particles of silica and titania by delivering a mixture of a silica precursor and a titania precursor to a burner, growing a porous preform by successively depositing the particles on a deposition surface while rotating and translating the deposition surface relative to the burner, and consolidating the porous preform into a dense glass.

Abstract: A low thermal expansion glass includes a base glass material having a front surface, a back surface, and a thickness and a glass coating material applied on at least the front surface of the base glass material. The base glass material consists essentially 10 wt % to 20 wt % titania and 80 wt % to 90 wt % silica. The glass coating material also consists essentially of titania and silica, but the total amount of titania in the glass coating material is lower than the total amount of titania in the base glass material. A silica-titania glass element suitable for extreme ultraviolet lithography applications consists of 12 wt % to 20 wt % titania and 80 wt % to 88 wt % silica and has a coefficient of thermal expansion of essentially 0 ?L/L in a temperature range of ?20° C. to +100° C.