Abstract:
The present invention provides doped titania-doped silica glass articles having low thermal expansions and low variations in thermal expansion. According to one embodiment of the invention, a titania-doped silica glass article has a titania content of between about 5 wt % and about 9 wt %; a coefficient of thermal expansion of between about −30 ppb/° C. and about +30 ppb/° C. at a temperature between 15° C. and 30° C.; and a variation in coefficient of thermal expansion of less than about 5 ppb/° C. at a temperature between 15° C. and 30° C.
Abstract:
The present disclosure relates to microspheres (i.e., beads) having a high index of refraction. The disclosure also relates to retroreflective articles, and in particular pavement markings, comprising such microspheres.
Abstract:
A silica glass containing TiO2, characterized in that the fluctuation of the refractive index (Δn) is at most 2×10−4 within an area of 30 mm×30 mm in at least one plane. A silica glass containing TiO2, characterized in that the TiO2 concentration is at least 1 mass %, and the striae pitch is at most 10 μm. An optical material for EUV lithography, characterized in that it is made of a silica glass containing TiO2, and the fluctuation of the refractive index (Δn) is at most 2×10−4 in a plane perpendicular to the incident light direction. An optical material for EUV lithography, characterized in that it is made of a silica glass containing TiO2, wherein the TiO2 concentration is at least 1 mass %, and the difference between the maximum value and the minimum value of the TiO2 concentration is at most 0.06 mass % in a plane perpendicular to the incident light direction.
Abstract:
The invention is directed to polished glass substrates suitable for extreme ultraviolet lithography. The elements are silica-titania glass elements having a coefficient of thermal expansion of 0±30×10−9/° C. or less, and containing 5-10 wt. % titania. The polished elements have a mid-spatial frequency peak-to-valley roughness of 2.0 ml/cm2/min. Generally the flow rates are in the range of 2.0-10 ml/cm2/min. Glass substrates suitable for extreme ultraviolet lithography element have a coefficient of thermal expansion of 0±30×10−9/° C. or less. A particular glass suitable for EUVL use is silica-titania glass containing 5-10 wt. % titania.
Abstract:
A silica glass containing TiO2, which has a fictive temperature of at most 1,200° C., a F concentration of at least 100 ppm and a coefficient of thermal expansion of 0±200 ppb/° C. from 0 to 100° C. A process for producing a silica glass containing TiO2, which comprises a step of forming a porous glass body on a target quartz glass particles obtained by flame hydrolysis of glass-forming materials, a step of obtaining a fluorine-containing porous glass body, a step of obtaining a fluorine-containing vitrified glass body, a step of obtaining a fluorine-containing formed glass body and a step of carrying out annealing treatment.
Abstract:
A method for manufacturing a GRIN lens includes the steps of forming a wet gel provided with a concentration distribution having a different concentration of a refractive index distribution imparting metal that differs in concentration in a radial direction, drying the wet gel to form a dry gel having a bulk specific gravity ρ (g/cm3), sintering the dry gel to form a GRIN lens base material and stretching the GRIN lens base material while heating. The method is characterized in that, in the step of sintering the dry gel, partial pressures of oxygen during sintering at 800° C. or higher are 10−1 Pa or lower and also the relation between a rate of temperature increase ν (° C./hr) and a bulk density ρ of the dry gel during sintering at 1,000 to 1,150° C. is defined by ν≦105*EXP (−12ρ). As a result of this, the GRIN lens, which has a large numerical aperture and a small diameter, can stably and easily be manufactured.
Abstract:
The invention is directed to a method for reducing striae in ultra-low expansion glass by heat-treating the glass at temperatures above 1600° C. for a time in the range of 72-288 hours. In one embodiment of the invention the glass is heat treated without forcing the glass to flow or “move”. The invention was found to reduce the magnitude of striae in an ultra-low expansion glass by 500%, and particularly reduces most of the “higher frequency” striae.
Abstract:
What is disclosed includes OD-doped synthetic silica glass capable of being used in optical elements for use in lithography below about 300 nm. OD-doped synthetic silica glass was found to have significantly lower polarization-induced birefringence value than non-OD-doped silica glass with comparable concentration of OH. Also disclosed are processes for making OD-doped synthetic silica glasses, optical member comprising such glasses, and lithographic systems comprising such optical member. The glass is particularly suitable for immersion lithographic systems due to the exceptionally low polarization-induced birefringence values at about 193 nm.
Abstract:
The present invention provides doped titania-doped silica glass articles having low thermal expansions and low variations in thermal expansion. According to one embodiment of the invention, a titania-doped silica glass article has a titania content of between about 5 wt % and about 9 wt %; a coefficient of thermal expansion of between about −30 ppb/° C. and about +30 ppb/° C. at a temperature between 15° C. and 30° C.; and a variation in coefficient of thermal expansion of less than about 5 ppb/° C. at a temperature between 15° C. and 30° C.
Abstract:
The present invention relates to microspheres (i.e., beads) that comprise titania and bismuth oxide. The glass microspheres further comprise zirconia. The invention also relates to retroreflective articles, and in particular pavement markings, comprising such microspheres.