Abstract:
The present invention relates to a substrate for EUV lithography optical member, comprising a silica glass containing TiO2, in which the substrate has two opposite surfaces, and the substrate has temperatures at which a coefficient of linear thermal expansion (CTE) is 0 ppb/° C. (Cross-Over Temperature: COT), and in which the two opposite surfaces have difference in the COTs of 5° C. or more.
Abstract:
An ytterbium-doped optical fiber of the present invention includes: a core which contains ytterbium, aluminum, and phosphorus and does not contain germanium; and a cladding which surrounds this core. The ytterbium concentration in the core in terms of ytterbium oxide is 0.09 to 0.68 mole percent. The molar ratio between the phosphorus concentration in the core in terms of diphosphorus pentoxide and the above ytterbium concentration in terms of ytterbium oxide is 3 to 30. The molar ratio between the aluminum concentration in the core in terms of aluminum oxide and the above ytterbium concentration in terms of ytterbium oxide is 3 to 32. The molar ratio between the above aluminum concentration in terms of aluminum oxide and the above phosphorus concentration in terms of diphosphorus pentoxide is 1 to 2.5.
Abstract:
The present invention relates to a substrate for EUV lithography optical member, comprising a silica glass containing TiO2, in which the substrate has two opposite surfaces, and the substrate has temperatures at which a coefficient of linear thermal expansion (CTE) is 0 ppb/° C. (Cross-Over Temperature: COT), and in which the two opposite surfaces have difference in the COTs of 5° C. or more.
Abstract:
A mixed quartz powder contains quartz powder and two or more types of doping element in an amount of from 0.1 to 20 mass %. The aforementioned doped elements include a first dope element selected from the group consisting of N, C and F, and a second dope element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, the lanthanides and the actinides. The “quartz powder” is a powder of crystalline quartz or it is a powder of glassy SiO2 particles. It is made form natural occurring quartz or it is fabricated synthetically. The “quartz powder” may be doped. The compounding ratio of the total amount (M1) of the aforementioned first elements and the total amount (M2) of the aforementioned second elements as the ratio of the number of atoms (M1)/(M2) is preferably from 0.1 to 20. Al as well as the aforementioned doped elements is preferably included in a mixed quartz powder of this invention.
Abstract:
The present invention is to provide a TiO2—SiO2 glass having suitable thermal expansion properties as an optical member of an exposure tool for EUVL. The present invention relates to a TiO2-containing silica glass having a temperature, at which a coefficient of thermal expansion is 0 ppb/° C., falling within the range of 23±4° C. and a temperature width, in which a coefficient of thermal expansion is 0±5 ppb/° C., of 5° C. or more.
Abstract:
The present invention is to provide a synthetic quartz glass body having a high light transmittance. The present invention provides a synthetic quartz glass body having pores in a surface part thereof.
Abstract:
The present invention is to provide a synthetic quartz glass body having a high light transmittance. The present invention provides a synthetic quartz glass body having pores in a surface part thereof.
Abstract:
Disclosed is an optical fiber having a silica-based core comprising an alkali metal oxide selected from the group consisting of K2O, Na2O, LiO2, Rb2O, Cs2O and mixtures thereof in an average concentration in said core between about 50 and 500 ppm by weight, said core further comprising chlorine and fluorine, wherein the average concentration of fluorine in said core is greater than the average concentration of alkali metal oxide in said core and the average concentration of chlorine in said core is greater than the average concentration of alkali metal oxide in said core; and a silica-based cladding surrounding and directly adjacent the core. By appropriately selecting the concentration of alkali metal oxide dopant in the core and the cladding, a low loss optical fiber may be obtained.
Abstract:
Disclosed are high purity synthetic silica glass material having a high OH concentration homogeneity in a plane perpendicular to the optical axis, and process of making the same. The glass has high refractive index homogeneity. The glass can have high internal transmission of at least 99.65%/cm at 193 nm. The process does not require a post-sintering homogenization step. The controlling factors for high compositional homogeneity, thus high refractive index homogeneity, include high initial local soot density uniformity in the soot preform and slow sintering, notably isothermal treatment during consolidation.
Abstract:
The present invention relates to an optical fiber for an optical amplifier and a method for manufacturing the same, which can be applied to an optical transmission system in the S-band area (4130 nm-1530 nm). According to the present invention, silica is used as a base material and the optical fiber for an optical amplifier contains Tm3+ ions and metal ions in a first core layer formed on an inner surface of a second core layer using the MCVD (Modified Chemical Vapor Deposition) method and a solution doping method whereby the practicability and productivity of the optical fiber are remarkably improved.