30 results about "Ultra low expansion glass" patented technology

The invention is directed to ultra-low expansion glasses to which adjustments have been made to selected variables in order to improve the properties of the glasses, and particularly to lower the expansivity of the glasses. The glasses are titania-doped silica glasses. The variables being adjusted include an adjustment in β-OH level; an adjustment to the cooling rate of the molten glass material through the setting point; and the addition of selected dopants to impact the CTE behavior.

The invention provides an ultra-low-expansion glass ceramic for a laser gyro and a preparation method thereof, wherein, the ultra-low-expansion glass ceramic includes the following ingredients according to mass percentages: 56-68% of SiO2, 21-27% of Al2O3, 2-4% of Li2, 0-1% of Na2, 0-1% of K2, 0-3% of MgO, 0-1.5% of ZnO, 4.5-6.8% of P2O5, 1-2.5% of TiO2, 1-2.5% of ZrO2 and 0.5-1.5% of Sb2O3/As2O3; the principal crystalline phase is beta quartz solid solution; the crystalline phase content is 70-85%; the grain size is lower than 50nm; and the magnitude order of coefficient of heat expansion is 10<-8>. The preparation method comprises the steps of dosing, mixing, melting, evening, clarifying, glass moulding, annealing and sitallization heat treatment, wherein, the steps of melting, evening and clarifying are carried out at 1570-1590 DEG C; the sitallization heat treatment comprises the steps as follows: the materials are crystallized after 6-10 hours of warm keeping at nucleating temperature of 650-750 DEG C with crystallizing rate of 1 DEG C/min; the crystallizing temperature is 750-850 DEG C; and the warm-keeping time is 6-10 hours. The buckling strength of the ultra-low expansion glass ceramic is higher than 170MPa; the process roughness is higher than 2-star; and the spectrum transmittance is more than 90% within the waveband of 0.6-2mum. In addition, the ultra-low-expansion glass ceramic has excellent hardness and abrasion resistance.

A low expansion silica-titania glass suitable for making extreme ultraviolet lithographic element, with the titania-containing silica glass having a titania content in the range of 5-10 wt. % and a including a further constituent of a viscosity reducing dopant having a content in the range of 0.001 to 1 wt %.

A high temperature micro-glassblowing process and a novel inverted-wineglass architecture that provides self-aligned stem structures. The fabrication process involves the etching of a fused quartz substrate wafer. A TSG or fused quartz device layer is then bonded onto the fused quartz substrate, creating a trapped air pocket or cavity between the substrate and the TSG device layer. The substrate and TSG device layer 14 are then heated at an extremely high temperature of approximately 1700° C., forming an inverted wineglass structure. Finally, the glassblown structure is cut or etched from the substrate to create a three dimensional wineglass resonator micro-device. The inverted wineglass structure may be used as a high performance resonator for use as a key element in precision clock resonators, dynamic MEMS sensors, and MEMS inertial sensors.

By measuring, for an ultra-low-expansion glass material, the frequency dependence of acoustic velocities and attenuation coefficients of bulk waves (longitudinal waves and shear waves), and the density, its fundamental acoustic properties are revealed, and a standard specimen for use in system calibration is prepared. By an absolute calibration method using the standard specimen, absolute values for both the LSAW and LSSCW velocities are obtained. Moreover, there are obtained relationships for the acoustic properties and the coefficient of thermal expansion to evaluate the coefficient of thermal expansion from the acoustic properties. In case there is a distribution of characteristics due to periodic striae, an accurate acoustic property distribution in the substrate can be ascertained and an evaluation performed, by selecting for the substrate a cutting angle with respect to the striae plane.

A method for joining at least two members of a lithographic apparatus is disclosed. The method includes providing a first member, providing a second member, direct-bonding the first member and the second member to form a direct-bond, and anodically bonding the first member and the second member. At least one of the members includes ultra low expansion glass and/or ultra low expansion glass ceramics.

Silica-titania glasses with small temperature variations in coefficient of thermal expansion over a wide range of zero-crossover temperatures and methods for making the glasses. The method includes a cooling protocol with controlled anneals over two different temperature regimes. A higher temperature controlled anneal may occur over a temperature interval from 750° C.-950° C. or a sub-interval thereof. A lower temperature controlled anneal may occur over a temperature interval from 650° C.-875° C. or a sub-interval thereof. The controlled anneals permit independent control over CTE slope and Tzc of silica-titania glasses. The independent control provides CTE slope and Tzc values for silica-titania glasses of fixed composition over ranges heretofore possible only through variations in composition.

A reflective reticle substantially reduces or eliminates pattern distortion that results from the absorption of EUV radiation while maintaining a reticle thickness consistent with industry standards. The reflective reticle includes a layer of ultra-low expansion (ULE) glass and a substrate of Cordierite having a thermal conductivity substantially larger than that of ULE glass. An aluminum layer is disposed onto a first surface of the ULE glass and a second surface of the ULE glass is polished to be substantially flat and defect-free. The Cordierite substrate can be directly bonded to the aluminum layer using anodic bonding to form the reflective reticle. Alternatively, a first surface of an intermediate Zerodur layer can be bonded to the aluminum layer, and a second aluminum layer can be used to anodically bond the Cordierite substrate to a second surface of the Zerodur layer, thereby forming the reflective reticle.

The invention relates to an ultra-low-expansion glass-ceramic super-stable treatment method. The invention adopts an air-sealing low conductive high temperature dependent non-metallic box (1). The method comprises the following steps that: an ultra-low-expansion glass-ceramic machining part (2) to be treated is placed in a heat treatment furnace (3), the heat treatment furnace is heated from the room temperature to a temperature ranging from 360 DEG C to 420 DEG C at a rate of 3-5 DEG C/min according to the demand, the temperature is kept for 8-12 hours, then the temperature is reduced at a rate of 0.05-0.2DEG C/min; and when the temperature of the treatment furnace is reduced to 120+/-20 DEG C, the treatment furnace control system is closed, and the treated machining part is placed in the furnace for 48 hours and then taken out. By adopting the ultra-low-expansion glass-ceramic super-stable treatment method, the internal stress existing in the machining part and the thermal deformation of the machining part can be effectively reduced so that the angle variation is less than 1 second of arc when the temperature changes from -50 DEG C to +100 DEG C; and the linear expansion coefficient of the glass-ceramic is ensured to be superior to 0.5*10<-7>/DEG C and the stabilization efficiency is increased.

The method of making optical fluoride crystal components provide optical components with beneficial final polished transmission surfaces for transmitting below 200 nm wavelengths of light, such as produced by excimer lasers and utilized in optical lithography. The invention utilizes colloidal silica soot in the polishing of optical fluoride crystal surfaces. This colloidal silica soot is a byproduct of chemical vapor deposition processing of fused silica or ultra low expansion glasses. The colloidal silica byproduct is referred to as "soot". Retaining the same physical properties as the parent glass and having a spherical morphology, the colloidal silica soot is an ideal for final polishing applications of optical fluoride crystals, and particularly for optical fluoride crystals such as calcium fluoride which have high transmission levels to below 300 nm light such as produced by excimer lasers. The soot has a large particle size and spherical shape when compared to conventional colloidal or fumed silica.

An ultralow-expansion glass ceramic continuous production line comprises a material selection system including a plurality of material conveyers; the material conveyers are each composed of a material conveyer belt, an electric screen and a burdening weighing device, the material conveyer belt is connected with the electric screen, and the electric screen is connected with the burdening weighing device; after passing through the burdening weighing device, the materials enter a mixing conveyer belt connected with a mixing unit, and a discharge port of the mixing unit is connected with a conveying rail device; one side of the conveying rail device is sequentially provided with a melting furnace, a forming unit, an annealing furnace, a sorting device and a crystallizing furnace; a back-conveying belt is disposed between the sorting device and the melting furnace; the melting furnace is connected with a water pipe. The ultra-low-expansion glass ceramic continuous production line and method have greatly improved production efficiency, save labor cost and have controllable product quality.

The invention relates to a method for measuring the thermal expansion coefficient of ultralow-expansion glass, and belongs to the technical field of ultrasonic detection. Ultrasonic propagation ratesat different positions of a radial mark of the ultralow-expansion glass are measured by using a water immersion type ultrasonic pulse echo method so as to achieve the measurement of the thermal expansion coefficient of the ultralow-expansion glass. The thermal expansion coefficient and the ultrasonic propagation rate of the ultralow-expansion glass are related to the TiO2 content in the glass, related researches show that the thermal expansion coefficient [alpha] of the ultralow-expansion glass and the ultrasonic propagation rate V are in a linear relationship, so that the thermal expansion coefficients at different positions can be deduced by measuring the ultrasonic propagation rates at different positions of the ultralow-expansion glass.

The invention relates to an integral production line for ultra-low expansion glass-ceramics. The integral production line comprises a raw material selecting and preparing system. The raw material selecting and preparing system comprises a plurality of raw material conveyors. Each raw material conveyor comprises a raw material conveying belt, an electric sieve and a material preparing and weighing device, wherein the raw material conveying belt is connected with the electric sieve, and the electric sieve is connected with the material preparing and weighing device. Raw materials pass the material preparing and weighing devices and enter a material mixing conveying belt connected with a material mixer. The raw materials fully mixed by the material mixer enters a conveying rail device. A melting furnace, a forming machine, an annealing furnace, a sorting device and a crystallization furnace are sequentially arranged on one side of the conveying rail device. A return belt is arranged between the sorting device and the melting furnace. The integral production line has the advantages that automatic production is achieved, various procedures of the production are in smooth butt joint, manpower cost is saved greatly, production efficiency is increased, and product quality is stable and controllable.

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 20DEG C. The second dopant can be optional. The composition of the glass article may also contain an OH concentration of less than 100 ppm.