Abstract: A method of producing soot, including: combusting a first fuel stream and a first oxidizer at a burner face; combusting a second fuel stream and a second oxidizer at the burner face, wherein the second fuel stream and the second oxidizer are premixed in advance of the burner face and a second equivalence ratio of the second fuel stream and the second oxidizer is less than about 1; and combusting a silicon-containing fuel into a plurality of soot particles, wherein the second fuel stream and the second oxidizer are combusted between the first fuel stream and the silicon-containing fuel. Applying this method of producing soot to deposit a preform suitable for the manufacture of optical fibers.

Abstract: This invention aims at providing a silicon electromagnetic casting apparatus for accurate and easy manufacturing of high quality silicon ingots. This apparatus uses a furnace vessel 100, a conductive crucible 200 installed in the internal part of the furnace vessel 100 and an induction coil 300 installed on the outer circumference of the crucible 200. Constant pressure is maintained in the internal part of the furnace vessel 100 using a prescribed gas and the silicon inside the above mentioned crucible 200 is solidified after melting it by induction heating by applying voltage on the induction coil 300. The induction coil 300 is made by placing 2 induction coils 310 and 320 having different induction frequencies one above the other.

Abstract: In order to improve the yield of an optical fiber base material, provided is a manufacturing apparatus for manufacturing an optical fiber base material by forming a soot deposition body on a surface of a target rod, including a main burner that generates glass microparticles to be deposited on the target rod while moving in a longitudinal direction of the target rod; a pair of side burners that are arranged outside a movement range of the main burner and heat both ends of the soot deposition body formed on the surface of the target rod; and a shielding member that prevents the glass microparticles generated by the main burner from being deposited on the target rod farther outward than a segment of the target rod sandwiched by the pair of side burners.

Abstract: An optical fiber base material manufacturing method includes: supplying oxygen, hydrogen, and silicide to a core deposition burner; depositing silicon dioxide; adjusting a drawing up speed so that a deposition tip position remains at the same position in accordance with growth of a porous base material; calculating an average of the drawing up speed at each preset time interval; calculating a difference of the calculated average from a preset value of the drawing up speed; correcting a flow rate of silicon tetrachloride when the supplied hydrogen is hydrogen produced or stored at normal temperature, and correcting a flow rate of hydrogen when the supplied hydrogen is hydrogen obtained by vaporizing liquid hydrogen, where when correcting the flow rate of hydrogen, a flow rate of hydrogen supplied to a cladding deposition burner is also corrected in a ratio of before and after the correction of the flow rate of the hydrogen.

Abstract: According to some embodiments a fiber sensor comprises: —an optical fiber configured for operation at a wavelength from about 300 nm to about 2000 nm, and further defined by a transmission end, another end, a fiber outer diameter and a fiber length, the fiber comprising: (a) a hybrid core comprising a single mode core portion and a multi-mode core portion; and (b) a cladding surrounding the hybrid core.

Abstract: The present invention relates to a process for preparing epitaxial ?-quartz layers on a solid substrate, to the material obtained according to this process, and to the various uses thereof, especially in the electronics field.

Abstract: Casting polycrystalline silicon includes placing a bottomless cooling crucible divided at least partially in the axis direction into a plurality of parts in the peripheral direction and having an inner surface coated with a release agent containing nitrogen, in an induction coil of a chamber charged with an inert gas; melting a raw material of polycrystalline silicon in the bottomless cooling crucible by electromagnetic induction heating using the induction coil; and pulling out the molten silicon downward while cooling and solidifying it. Pullout of the solidified molten silicon is performed through adjusting the carbon concentration of the molten silicon to 4.0×1017 atoms/cm3 or more to 6.0×1017 atoms/cm3 or less, the oxygen concentration thereof to 0.3×1017 atoms/cm3 or more to 5.0×1017 atoms/cm3 or less, and the nitrogen concentration to 8.0×1013 atoms/cm3 or more to 1.0×1018 atoms/cm3 or less.

Abstract: Methods and apparatuses for forming optical preforms from silica glass soot are disclosed. According to one embodiment, a method for forming an optical preform may include loading silica glass soot in a mold cavity of a mold body. The mold body may be rotated at a rotational speed sufficient to force the silica glass soot towards an inner wall of the mold body. Thereafter the silica glass soot is compressed in an inward radial direction as the mold body is rotated to form a soot compact layer.

Abstract: A multi-line mass flow device configured for controlled delivery of two or more fluids into a process chamber. The multi-line mass flow device comprises a cluster mass flow control manifold and a multi-inlet manifold. The cluster mass flow control manifold comprises a controller, a gas manifold mounting block, and two or more gas flow control stations. The multi-inlet manifold comprises a multi-inlet mounting block, and two or more isolation valves mounted on the multi-inlet mounting block.

Abstract: A novel array of hollow silica glass microneedles is provided. The array is prepared from a silica dispersion. A novel apparatus is provided comprising a negative mold component having tapered openings therein and a positive mold component having positive elements that are received within the tapered openings of the negative mold component. An assembly is prepared of the negative mold component and the positive mold component, with an aqueous silica dispersion received within the space between the outer surface of the positive elements and the inner surface of the openings. The assembly is heated to remove air and water vapors from the silica dispersion, then the assembly is further heated to sinter the remaining silica to silica glass. The sintered silica glass when removed from the mold components is in the form of an array of microneedles.

Abstract: A burner module comprising a burner gas inlet block, a lower flow plate, an upper flow plate, a burner gas flow disperser, and a burner gas discharge block. The burner gas inlet block, the burner gas flow disperser, and the burner gas discharge block each comprising a plurality of channels separated by partitions. The partitions of the burner gas flow disperser and the burner gas discharge block comprising a knife edge. The upper flow plate and the lower flow plate each comprising a plurality of pressure holes in fluid communication with the plurality of channels. Additionally, the method of forming a glass sheet or ribbon using the disclosed burner module and a glass sheet or ribbon formed using the method.

Abstract: Synthetic sintered YPO4 composite materials comprising excess amount of Y2O3 in the composition and process for making such materials. The Y2O3-modified sintered YPO4 composite material exhibits improved mechanical properties compared to stoichiometric YPO4 materials. The modified YPO4 materials can be used to produce different components used in the glass-making process such as, for example, an isopipe.

Abstract: Provided is a method for manufacturing a vitreous silica crucible and a manufacturing apparatus for the same, which can reduce the amount of bubbles and impurities of a crucible inner surface and enhance a crystallization yield of silicon single crystal. A method for manufacturing a vitreous silica crucible of the invention includes a silica powder supplying process of supplying silica powder in a rotating mold to form a silica powder layer; an arc fusing process of fusing the silica powder layer by arc discharge generated by carbon electrodes; and a fire polishing process of throwing an arc flame toward a target surface of the silica powder layer for surface removal, wherein, in the fire polishing process, the distances from the tips of the carbon electrodes to the target surface is set to be equal.

Abstract: There are provided an apparatus and a method for manufacturing a vitreous silica crucible which can prevent the deterioration of the inner surface property in the manufacturing process of a vitreous silica crucible. The apparatus includes a mold defining an outer shape of a vitreous silica crucible, and an arc discharge unit having electrodes and a power-supply unit, wherein each of the electrodes includes a tip end directed to the mold, the other end opposite to the tip end, and a bent portion provided between the tip end and the other end.

Abstract: There is provided a method of manufacturing a vitreous silica crucible having non-bubbles on the inner surface without necessitating new apparatuses for grinding and polishing and without damaging the productivity. According to the present invention, there is provided a method of manufacturing a vitreous silica crucible including the processes of: gathering a vitreous silica layer containing residual bubbles existing in a near-surface region of the transparent layer of the vitreous silica crucible by controlling the number of rotations applied to the vitreous silica crucible in a state that an inner surface side of the vitreous silica crucible is fused by arc heating; and moving a portion of a non-bubble layer in the surface of the transparent layer exposed by movement of the residual bubble-containing layer to cover a region in which bubbles have gathered with the non-bubble layer.

Abstract: A burner module comprising a burner gas inlet block, a lower flow plate, an upper flow plate, a burner gas flow disperser, and a burner gas discharge block. The burner gas inlet block, the burner gas flow disperser, and the burner gas discharge block each comprising a plurality of channels separated by partitions. The partitions of the burner gas flow disperser and the burner gas discharge block comprising a knife edge. The upper flow plate and the lower flow plate each comprising a plurality of pressure holes in fluid communication with the plurality of channels. Additionally, the method of forming a glass sheet or ribbon using the disclosed burner module and a glass sheet or ribbon formed using the method.

Abstract: A high-surface quality glass sheet is formed using a roll-to-roll glass soot deposition and sintering process. The glass sheet formation involves providing glass soot particles, depositing a first fraction of the glass soot particles on a deposition surface to form a supported soot layer, electrostatically attracting and collecting a second fraction of the glass soot particles onto a surface of a charged plate, removing the soot layer from the deposition surface to form a soot sheet, and heating at least a portion of the soot sheet to sinter the glass soot particles to form a glass sheet.

Abstract: An arc discharge method includes the steps of heating and melting a non-conductive object by arc discharge using a plurality of carbon electrodes in a output range of 300 to 12,000 kVA; and setting a ratio of the distance between a contact position at which the carbon electrodes come in contact with each other and a front end to the diameter of the carbon electrode during the start of the arc discharge to be in the range of 0.001 and 0.9.

Abstract: A mold for making a fused silica crucible includes a cylindrical can having an interior bore. A graphite insert is received in the bore and has an upper surface adapted to form the lower surface of the crucible while the interior bore of the can forms the side wall of the crucible. Silica grain is deposited in the mold while it rotates. Bores formed in the can above the insert and in the insert draw air through the silica during fusion.

Abstract: A glass sheet is formed using a roll-to-roll glass soot deposition and sintering process. The glass sheet formation involves forming a first glass soot layer on a deposition surface of a soot-receiving device, removing the first glass soot layer from the deposition surface, and forming a second glass soot layer on the unsupported first glass soot layer. The resulting composite glass soot sheet is heated to form a sintered glass sheet. The glass sheet can be a substantially homogeneous glass sheet or a composite glass sheet having layer-specific attributes.

Abstract: Provided is an apparatus for manufacturing a vitreous silica crucible, which is capable of stably manufacturing a high quality vitreous silica crucible by stabilizing heat generation through an arc discharge. The apparatus for manufacturing a vitreous silica crucible includes a mold that defines a shape of a vitreous silica crucible, carbon electrodes that generate an arc discharge for fusing a silica powder molded body formed in the mold, and a power supply device that supplies power to the carbon electrodes. The power supply device includes a saturable reactor that is provided on a supply path of the power to the carbon electrodes and has variable reactance, and a control device that controls the power supplied to the carbon electrodes by changing the reactance of the saturable reactor.

Abstract: During fabrication of a vitreous silica crucible, contamination of the vitreous silica crucible due to wear particles and debris of components of an apparatus for manufacturing a vitreous silica crucible is reduced by preventing damage and wear of the components of the apparatus due to silica fume. The apparatus for manufacturing a vitreous silica crucible is divided into a lower section for accommodating a mold and a mold driving system and an upper section for accommodating an arc electrode driving system, wherein a sectioning member including one or more communication paths for allowing penetration of arc electrodes, thereby the air flow is controlled so as to reduce exchange between gas in the upper section and gas in the lower section.

Abstract: During fabrication of a vitreous silica crucible, contamination of the vitreous silica crucible due to wear particles and debris of components of an apparatus for manufacturing a vitreous silica crucible is reduced by preventing damage and wear of the components of the apparatus due to silica fume. The apparatus for manufacturing a vitreous silica crucible is divided into a lower section for accommodating a mold and a mold driving system and an upper section for accommodating an arc electrode driving system, wherein a sectioning member including one or more communication paths for allowing penetration of arc electrodes, thereby the air flow is controlled so as to reduce exchange between gas in the upper section and gas in the lower section.

Abstract: A vitreous silica crucible manufacturing apparatus includes a plurality of carbon electrodes configured to heat and melt raw material powder by arc discharge, and a value of a ratio R2/R1 of a diameter R2 of a front end of each of the carbon electrodes to a diameter R1 of a base end is set in a range of 0.6 to 0.8. Each carbon electrode has a diameter reduction portion formed at a front end position and reduced in diameter from a diameter R3 of a base end side to the diameter R2 of the front end. When a length of the diameter reduction portion is L1, the diameter of the front end is R2, the diameter of the base end is R1, an angle between the axis lines of the carbon electrodes is ?1, and X=(R1?R2)/2, a value of L1?(X/tan(?1/2)) is set in a range of 50 to 150 mm.

Abstract: Accurate temperature measurement during manufacturing a vitreous silica crucible is enabled. The present invention provides an apparatus for manufacturing a vitreous silica crucible including: a mold for forming a silica powder layer by supplying silica powder therein; an arc discharge unit having carbon electrodes and a power supply unit and for heating and fusing the silica powder layer by arc discharge; and a temperature measurement unit for measuring temperature of a fused portion in the mold, wherein the temperature measurement unit is an radiation thermometer for measuring temperature by detecting radiation energy of a wavelength of 4.8 to 5.2 ?m.

Abstract: Provided is a method for manufacturing a vitreous silica crucible and a manufacturing apparatus for the same, which can reduce the amount of bubbles and impurities of a crucible inner surface and enhance a crystallization yield of silicon single crystal. A method for manufacturing a vitreous silica crucible of the invention includes a silica powder supplying process of supplying silica powder in a rotating mold to form a silica powder layer; an arc fusing process of fusing the silica powder layer by arc discharge generated by carbon electrodes; and a fire polishing process of throwing an arc flame toward a target surface of the silica powder layer for surface removal, wherein, in the fire polishing process, the distances from the tips of the carbon electrodes to the target surface is set to be equal.

Abstract: There are provided an apparatus and a method for manufacturing a vitreous silica crucible which can prevent the deterioration of the inner surface property in the manufacturing process of a vitreous silica crucible. The apparatus includes a mold defining an outer shape of a vitreous silica crucible, and an arc discharge unit having electrodes and a power-supply unit, wherein each of the electrodes includes a tip end directed to the mold, the other end opposite to the tip end, and a bent portion provided between the tip end and the other end.

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: A mold for the production of a silica crucible by heat-fusing silica or quartz powder attached onto an inner wall of a rotating mold, wherein a ring-shaped heat insulating barrier material having a specified inner diameter is disposed on an inner peripheral wall of an upper opening portion of the mold corresponding to an upper region of the silica crucible.

Abstract: In a mold for use in the production of a silica crucible, a mold cover corresponding to a small-diameter thinned portion of an upper part of the silica crucible is detachably disposed on a mold substrate corresponding to a main body of the silica crucible, and the mold cover has a barrier function against arc heating, and an inner diameter of the mold cover is smaller than that of the mold substrate but larger than that of the silica crucible.

Abstract: There is provided a mold for use in the production of a silica crucible by heat-fusing silica or quartz powder attached onto an inner wall of a rotating mold, wherein an inner side of an upper opening portion of the mold corresponding to an upper part of the silica crucible is ground to obtain a step portion and a ring-shaped heat insulating barrier member having an inner diameter smaller than that of the mold is disposed on the step portion through a hollow disk-shaped support member having an inner diameter equal to or somewhat larger than that of the heat insulating barrier member.

Abstract: In a mold for use in the production of a silica crucible, a cylindrical rim member is engagedly supported through hooks to an inner side of an upper opening portion of the mold corresponding to an upper part of a silica crucible and an outer diameter of the rim member is smaller than an inner diameter of the mold but larger than an inner diameter of the silica crucible.

Abstract: Provided is a method of manufacturing a vitreous silica crucible, including: an arc fusing process for fusing the silica powder molded body by using arc flames generated from the plurality of carbon electrodes, wherein the arc fusing process is performed in a state of disposing tips of at least a pair of carbon electrodes of the plurality of carbon electrodes closer to a target surface of the silica powder molded body than other carbon electrode tips, and setting distances from each of the tips of the closer carbon electrodes to the target surface, to be equal, and the arc fusing process is performed by heating and fusing the silica powder molded body while performing fire polishing, which partially removes an inner surface of the silica powder molded body by using arc flames generated by the closer carbon electrodes.

Abstract: A rotating mold has a plurality of air channels that communicate with a cavity formed in the mold. Silica grain is deposited in the rotating mold and then formed into the shape of a crucible having a lower portion that comprises a substantially uniformly thick wall. An upper portion of the grain is formed into a substantially narrowed wall portion about the perimeter of the formed shape. The silica grain is heated, and a pump draws gas through the air channels while the silica fuses. There is a pressure drop across the narrowed wall portion. After fusing, the upper portion of the crucible, including the narrowed wall portion, is cut off.

Abstract: The invention is concerned with a material which shows low absorption for UV radiation having a wavelength below 250 nm, low birefringence, high chemical resistance and high radiation resistance and which is therefore particularly usable for making optical components for microlithography. According to the invention the material consists of synthetically produced quartz crystallites which form a polycrystalline structure and have a mean grain size in the range between 500 nm and 30 ?m. The method according to the invention for making a blank from the material comprises providing granules consisting of synthetically produced quartz crystals having a mean grain size in the range between 500 nm and 30 ?m, and sintering the granules to obtain a blank of polycrystalline quartz.

Abstract: A vitreous silica crucible manufacturing apparatus includes a plurality of carbon electrodes configured to heat and melt raw material powder by arc discharge, and a value of a ratio R2/R1 of a diameter R2 of a front end of each of the carbon electrodes to a diameter R1 of a base end is set in a range of 0.6 to 0.8. Each carbon electrode has a diameter reduction portion formed at a front end position and reduced in diameter from a diameter R3 of a base end side to the diameter R2 of the front end. When a length of the diameter reduction portion is L1, the diameter of the front end is R2, the diameter of the base end is R1, an angle between the axis lines of the carbon electrodes is ?1, and X=(R1?R2)/2, a value of L1?(X/tan(?1/2)) is set in a range of 50 to 150 mm.

Abstract: A known method for producing a cylinder of quartz glass comprises a method step in which a porous SiO2 body comprising a central inner bore, a lower end and an upper end is sintered in a sintering furnace zone by zone, starting from the upper end, to obtain the quartz glass cylinder, a holding device being used by means of which the SiO2 body is held standing in vertical orientation during a first sintering phase and suspended in a second sintering phase.

Abstract: The arc discharge apparatus comprises a plurality of carbon electrodes connected to respective phases of a power supply for heating a silica powder and causing it to fuse by generating arc discharge between the carbon electrodes. All of the carbon electrodes have a density in a range from 1.30 g/cm3 to 1.80 g/cm3, and variability in density among the carbon electrodes is 0.2 g/cm3 or less. The carbon particles that constitute the carbon electrodes preferably have a particle diameter of 0.3 mm or less.

Abstract: A method of manufacturing a fused silica crucible by heating and melting a vitreous silica powder compact shaped into a mold using arc discharge of electrodes arranged around a rotation shaft of the mold, includes the steps of: arranging the electrodes in a ring shape, and setting a ratio W/R of a horizontal distance W between the electrode front end and the surface of the vitreous silica powder compact to a vitreous silica powder compact opening radius R, for at least a predetermined time during arc heating, to be in the range of 0.002 to 0.98.

Abstract: An arc discharge method of the present invention includes the steps of: heating and melting a non-conductive object by arc discharge using a plurality of carbon electrodes in an output range of 300 to 12,000 kVA; and setting a ratio of the distance between a contact position at which the carbon electrodes come in contact with each other and a front end to the diameter of the carbon electrode during the start of the arc discharge to be in the range of 0.001 to 0.9.

Abstract: An apparatus and process for making glass soot sheet and sintered glass sheet. Glass soot particles are deposited on a curved deposition surface of a rotating drum to form a soot sheet. The soot sheet is then released from the deposition surface. The soot sheet can be sintered into a consolidated glass. The soot sheet and the sintered glass can be sufficiently long and flexible to be reeled into a roll.

Abstract: A method for forming a silica glass blank includes generating soot using an array of soot producing burners, directing the soot along a first direction onto a bait, collecting the soot on the bait, imparting relative oscillatory motion having a repeat period between the array of soot producing burners and the bait along a second direction orthogonal to the first direction while collecting the soot, and offsetting the relative oscillatory motion by a selected distance along the second direction after each repeat period.

Abstract: Problem To provide a method for manufacturing silica glass and device for manufacturing silica glass that facilitates the simple manufacture of a highly pure, bubble-free large flat-plate silica glass ingot in a short time. Solving Means In a method for manufacturing silica glass in which a silica glass powder is dropped from a powder supply device above a rotating furnace and layered in a centre portion of a furnace bottom, and then heat-fused and expanded in an outer circumferential direction of the furnace to form an ingot, the drop position and a fusion position of the silica glass powder is dispersed in the bottom portion of the furnace. The drop position of the silica glass powder is displaced from the centre portion of the bottom portion of the furnace, and the silica glass powder is preferably dispersed in the bottom portion of the furnace by the rotational movement of one or both of the powder supply device and the bottom portion of the furnace.

Abstract: A conformable nosing device is described herein which conforms to have a bowed shape that substantially matches a bowed shape of a glass sheet and which engages the glass sheet to help minimize the motion of the glass sheet and to help reduce the stress within the glass sheet while the glass sheet is being scored and separated into individual glass sheets. In addition, the conformable nosing device can include a passive nosing device which can be controlled to further help minimize the motion of the glass sheet while the glass sheet is being scored and separated into individual glass sheets.

Abstract: The invention provides a method for manufacturing a large scale quartz glass slab ingot in a flame hydrolysis reaction in a furnace, including the steps of rotating the furnace, depositing a fused silica on a furnace bed, and extending the deposit outwardly by heating and rotation of the furnace, thereby a quartz glass slab ingot is obtained. A quartz glass burner is installed at the ceiling of the furnace, hydrogen gas supplied to the burner flows down along the tapered wall of the oxygen chamber and is ejected into the outer casing. Part of the hydrogen gas is deflected to the center of the burner and mixed with the oxygen just after the ejection from the oxygen gas nozzles. Thereby, the flame is formed smoothly and the thermal efficiency is improved. The flame becomes wide enough and the silica powder transported by the hydrogen gas is uniformly fused by the flame and heat capacity of the fused silica.

Abstract: A method for forming EUV LITHOGRAPHY GLASS STRUCTURES WITH VOIDS is disclosed which includes forming a slurry mixture including silica soot particles, and inserting the slurry mixture into a casting mold. The method provides low weight mass reduced rigid glass structures with beneficial thermal stability. The casting mold includes therein a casting form. The casting form is adapted to provide selected geometry void spaces within the glass lithography structure. The slurry mixture is dried to form a green ware object. The casting form is removed from the green ware and the green ware object is consolidated into a lithography glass structure with voids.

Abstract: An object of the invention is to provide a quartz glass crucible for pulling up silicon single crystal and a method for producing the same, suitable for improving the productivity of the crucible and the quality of the silicon single crystal, which, by forming a crystalline layer on the inner surface of the quartz glass crucible during pulling up silicon single crystal, prevents degradation from occurring on the inner surface of the crucible and increases the ratio of single crystal while preventing the dislocation from forming on the single crystals.

Abstract: Disclosed is a method of making a photonic crystal preform using a pore former in combination with silica particles and a binder to form a paste that can be extruded into a greenware body. The pore former can be removed from the greenware body by heating. The brownware body resulting from the heating step has a high porosity that facilitates the removal of impurities, including OH, during subsequent cleansing and sintering stages. The methods disclosed allow the manufacture of relatively large photonic crystals and are flexible enough to provide a periodic array of channels or passageways as the crystal features.

Abstract: Methods and apparatus for producing fused silica members having high internal transmission are disclosed. The apparatus and methods are capable of producing fused silica having internal transmission of at least 99.65%/cm at 193 nm.

Abstract: The present invention relates to a method of making a soot particle and apparatus for making such soot particle. Preferably the method of making the soot particle is substantially free of the step of combusting a fuel and substantially free of the step of forming a plasma. Preferably, the apparatus is devoid of a heating element associated with both combustion and formation of a plasma. A preferred technique for at least one heating step for forming the soot particle is induction heating.