Abstract:
A method for manufacturing a primary preform for optical fibers using an internal vapor deposition process, including the steps of: i) providing a hollow glass substrate tube having a supply side and a discharge side, ii) surrounding at least part of the hollow glass substrate tube by a furnace, iii) supplying a gas flow, doped or undoped, of glass-forming gases to the interior of the hollow glass substrate tube via the supply side thereof, iv) creating a reaction zone in which conditions such that deposition of glass will take place on the interior of the hollow glass tube are created, and v) moving the reaction zone back and forth in longitudinal direction over the hollow glass substrate tube between a reversal point located near the supply side and a reversal point located near the discharge side of the hollow glass substrate tube.
Abstract:
In one aspect the disclosure is directed to a binary silica-titania glass blank having a CTE of 0±30 ppb/° C. or less over a temperature range of 5° C. to 35° C., and a doped silica-titania glass critical zone, wherein the dopant(s) are selected from the group consisting of aluminum oxide, and transition metal oxides, and amount of the dopant(s) is in the range of 0.05 wt. % to 8 wt. %. In various embodiments the dopants are selected from the group consisting of 0.25 wt. % to 8 wt. % Al2O3, 0.05 wt. % to 3 wt. % Nb2O5, and 0.25 wt. % to 6 wt. % Ta2O5, and mixtures thereof.
Abstract:
A process for producing a porous quartz glass body containing hydrolyzing a metal dopant precursor and an SiO2 precursor in a flame of a burner to form glass fine particles, and depositing and growing the formed glass fine particles on a base material, in which the burner has at least two nozzles, and in which a mixed gas containing (A) a metal dopant precursor gas, (B) an SiO2 precursor gas, (C) one gas of H2 and O2, and (D) one or more gases selected from the group consisting of a rare gas, N2, CO2, a hydrogen halide and H2O, with a proportion of the gas (D) being from 5 to 70 mol %; and (E) the other gas of H2 and O2 of (C), are fed into different nozzles of the burner from each other.
Abstract:
A method for the production of a mirror element (10) that has a reflective coating (10a) for the EUV wavelength range and a substrate (10b). The substrate (10b) is pre-compacted by hot isostatic pressing, and the reflective coating (10a) is applied to the pre-compacted substrate (10b). In the method, either the pre-compacting of the substrate (10b) is performed until a saturation value of the compaction of the substrate (10b) by long-term EUV irradiation is reached, or, for further compaction, the pre-compacted substrate (10b) is irradiated, preferably homogeneously, with ions (16) and/or with electrons in a surface region (15) in which the coating (10a) has been or will be applied. A mirror element (10) for the EUV wavelength range associated with the method has a substrate (10b) pre-compacted by hot isostatic pressing. Such a mirror element (10) is suitable to be provided in an EUV projection exposure system.
Abstract:
On an EUV light-reflecting surface of titania-doped quartz glass, an angle (θ) included between a straight line connecting an origin (O) at the center of the reflecting surface to a birefringence measurement point (A) and a fast axis of birefringence at the measurement point (A) has an average value of more than 45 degrees. Since fast axes of birefringence are distributed in a concentric fashion, a titania-doped quartz glass substrate having a high flatness is obtainable which is suited for use in the EUV lithography.
Abstract:
The present invention relates to a process for production of a TiO2—SiO2 glass body, comprising a step of, when an annealing point of a TiO2—SiO2 glass body after transparent vitrification is taken as T1(° C.), holding the glass body after transparent vitrification in a temperature region of from T1−90(° C.) to T1−220(° C.) for 120 hours or more.
Abstract:
The present invention relates to a process for producing a porous quarts glass body containing hydrolyzing a metal dopant precursor and an SiO2 precursor in a flame of a burner to form glass fine particles, and depositing and growing the formed glass fine particles on a base material, in which the burner has at least two nozzles, and in which a mixed gas containing (A) a metal dopant precursor gas, (B) an SiO2 precursor gas, (C) one gas of H2 and O2, and (D) one or more gases selected from the group consisting of a rare gas, N2, CO2, a hydrogen halide and H2O, with a proportion of the gas (D) being from 5 to 70 mol %; and (E) the other gas of H2 and O2 of (C), are fed into different nozzles of the burner from each other.
Abstract:
An optically active glass and an optical fiber comprising such glass, having reduced photodarkening properties are provided. The optically active glass is mainly composed of silica representing from about 50 to 98 mol % of the glass. It also includes at least one active ion, such as a rear-earth ion, which induces a photodarkening effect in optical properties of the glass. Moreover, the glass includes an effective amount of phosphorus oxide providing the photodarkening reducing effect, preferably in an amount of from about 1 to 30 mol %. A method for reducing a photodarkening effect in optical properties of an optically active glass including the step of introducing phosphorus oxide to the glass is also provided.
Abstract:
A near-net or net shape fused silica glass article, such as a radome. The article is formed by depositing silica soot onto a mandrel having a shape that corresponds to the shape of the fused silica glass article. In some embodiments, the mandrel is inductively heated to a temperature that is sufficient to consolidate or sinter the silica soot upon deposition onto the mandrel to form fused silica glass. The fused silica glass article may have an outer layer that is under compression and/or multiple layers comprising various dopants that can alter or affect physical, mechanical, electrical, and/or optical properties.
Abstract:
The present invention provides a TiO2-containing silica glass from which a transparent extremely low thermal expansion glass having excellent transparency and having a temperature region in which the coefficient of thermal expansion is substantially zero can be obtained. The present invention relates to a TiO2-containing silica glass for optical member for EUV lithography, having a TiO2 concentration of from 3 to 14% by mass; an internal transmittance per 1-mm thickness in a wavelength region of from 400 to 700 nm, T400-700, of 97% or more; and an internal transmittance per 1-mm thickness in a wavelength region of from 400 to 3,000 nm, T400-3,000, of 70% or more.