摘要:
A known method for producing synthetic quartz glass comprises the method steps: (a) forming a cylindrical SiO2 soot body having an inner portion and at least one free cylinder jacket surface surrounding the inner portion; (b) thermally drying the porous soot body; and (c) vitrifying the dried soot body with formation of the cylinder from synthetic quartz glass. Starting therefrom, to indicate a method which permits a particularly flat radial distribution in the inner portion of the cylinder, it is suggested according to the invention that the dried SiO2 soot body that is present after method step b) should be subjected to a homogenizing method prior to vitrification, the homogenizing method comprising the following steps: (I) heating the soot body to a consolidation temperature to form a sealing layer in the area of the at least one cylinder jacket, the sealing layer sealing the inner portion to the outside; (II) cooling the soot body from the consolidation temperature; and (III) annealing the soot body in the range of a homogenization temperature during a period of at least 5 hours so that the radial profile of the hydroxyl group concentration flattens in the inner portion.
摘要:
A known method for producing synthetic quartz glass comprises the method steps: (a) forming a cylindrical SiO2 soot body having an inner portion and at least one free cylinder jacket surface surrounding the inner portion; (b) thermally drying the porous soot body; and (c) vitrifying the dried soot body with formation of the cylinder from synthetic quartz glass. Starting therefrom, to indicate a method which permits a particularly flat radial distribution in the inner portion of the cylinder, it is suggested according to the invention that the dried SiO2 soot body that is present after method step b) should be subjected to a homogenizing method prior to vitrification, the homogenizing method comprising the following steps: (I) heating the soot body to a consolidation temperature to form a sealing layer in the area of the at least one cylinder jacket, the sealing layer sealing the inner portion to the outside; (II) cooling the soot body from the consolidation temperature; and (III) annealing the soot body in the range of a homogenization temperature during a period of at least 5 hours so that the radial profile of the hydroxyl group concentration flattens in the inner portion.
摘要:
An object of the present invention is to provide an improved blank such that an optical member of a high homogeneity can be obtained therefrom, and to provide a vessel and a heat treatment method for heat-treating a highly uniform synthetic quartz blank. In a first aspect of the invention a special designed blank is provided showing a concave shaped outer surface. In a second aspect of the invention a special designed vessel for heat-treating blanks is provided, whereby the degree of heat emission at the center is set higher than that of the surroundings.
摘要:
In a known method for producing quartz glass that is doped with nitrogen, an SiO2 base product is prepared in the form of SiO2 grains or in the form of a porous semi-finished product produced from the SiO2 grains and the SiO2 base product is processed into the quartz glass with the nitrogen chemically bound therein in a hot process in an atmosphere containing a reaction gas containing nitrogen. From this starting point, a method is provided for achieving nitrogen doping in quartz glass with as high a fraction of chemically bound nitrogen as possible. This object is achieved according to the invention in that a nitrogen oxide is used as the nitrogen-containing reaction gas, and that a SiO2 base product is used that in the hot process has a concentration of oxygen deficient defects of at least 2×1015 cm−3, wherein the SiO2 base product comprises SiO2 particles having an average particle size in the range of 200 nm to 300 μm (D50 value).
摘要:
The present invention relates to a quartz glass blank for an optical component for transmission of ultraviolet radiation of a wavelength of 250 nm or shorter, and to a use of the quartz glass blank in microlithography in combination with ultraviolet radiation of a wavelength of 250 nm or shorter. Moreover, the invention relates to a procedure for manufacture of the quartz glass blank. A quartz glass blank of the described type should show little induced absorption and be optimized with respect to compaction and decompaction. The quartz glass blank according to the invention is characterized by the following properties: a glass structure essentially free of oxygen defect sites, an H2-content in the range of 0.1×1016 molecules/cm3 to 4.0×1016 molecules/cm3, an OH-content in the range of 125 wt-ppm to 450 wt-ppm, an SiH group-content of less than 5×1016 molecules/cm3, a refractive index inhomogeneity, Δn, of less than 2 ppm, and a stress birefringence of less than 2 nm/cm. In the use according to the invention, the quartz glass blank complies with dimensioning rules (2), (3), and (4) in terms of its OH-content, minimal and maximal hydrogen contents, COH, CH2min, and CH2max, respectively, with P being the pulse number and ε being the energy density: COH [wt-ppm]=1,700×ε[mJ/cm2]0.4±50, (2) CH2min [molecules/cm3]=1×106ε2 P, (3) CH2max [molecules/cm3]=2×1018ε. (4) The procedure according to the invention is characterized in that a mixed quartz glass is generated from a first and a second quartz glass by mixing the two quartz glasses.
摘要:
The present invention relates to a quartz glass blank for an optical component for transmission of ultraviolet radiation of a wavelength of 250 nm or shorter, and to a use of the quartz glass blank in microlithography in combination with ultraviolet radiation of a wavelength of 250 nm or shorter. Moreover, the invention relates to a procedure for manufacture of the quartz glass blank. A quartz glass blank of the described type should show little induced absorption and be optimized with respect to compaction and decompaction. The quartz glass blank according to the invention is characterized by the following properties: a glass structure essentially free of oxygen defect sites, an H2-content in the range of 0.1×1016 molecules/cm3 to 4.0×1016 molecules/cm3, an OH-content in the range of 125 wt-ppm to 450 wt-ppm, an SiH group-content of less than 5×1016 molecules/cm3, a refractive index inhomogeneity, Δn, of less than 2 ppm, and a stress birefringence of less than 2 nm/cm. In the use according to the invention, the quartz glass blank complies with dimensioning rules (2), (3), and (4) in terms of its minimal and maximal hydrogen contents and OH-content, CH2min, CH2max, and COH, respectively, with P being the pulse number and ε being the energy density (in mJ/cm2): CH2min [molecules/cm3]=1×106ε2P, (2) CH2max [molecules/cm3]=2×1018ε, (3) COH [wt-ppm]=1,700×ε[mJ/cm2]0.4±50. (4) The procedure according to the invention is characterized in that a mixed quartz glass is generated from a first and a second quartz glass by mixing the two quartz glasses in the course of a homogenization treatment.
摘要:
The invention relates to a previously known method for producing synthetic silica glass, comprising the following steps: a gas stream containing a vaporizable initial substance, which can be converted into SiO2 by means of oxidation or flame hydrolysis, is formed; the gas stream is delivered to a reaction zone in which the initial substance is converted so as to form amorphous SiO2 particles; the amorphous SiO2 particles are deposited on a support so as to form an SiO2 layer; and the SiO2 is vitrified during or following deposition of the SiO2 particles in order to obtain the silica glass. The aim of the invention is to create an economical method for producing synthetic silica glass, which is characterized by a favorable damaging behavior towards short-wave UV radiation while being particularly suitable for producing an optical component used for transmitting high-energy ultraviolet radiation having a wavelength of 250 nm or less. Said aim is achieved by using a mixture of a monomeric silicon compound containing a singular Si atom and an oligomeric silicon compound containing several Si atoms as an initial substance, provided that the oligomeric silicon compound in the mixture contributes less than 70 percent to the total silicon content.
摘要:
In a known process for producing a quartz glass cylinder, a porous soot tube, which is sintered to form the quartz glass cylinder, is produced by depositing SiO2 particles on an outer cylindrical surface of a support, which rotates about the longitudinal axis thereof and has a layer of silicon carbide (SiC layer). In order on this basis to specify a support having a high resistance to fracture, which firstly can easily be removed and which secondly presents a low risk of contamination for the soot body, the invention proposes that the SiC layer is treated at a high temperature in an oxygen-containing atmosphere before the SiO2 particles are deposited, in such a manner that an SiO2 protective layer having a thickness of at least 0.1 μm is produced by oxidation.
摘要:
In a known method for drawing a tubular quartz glass strand, a crucible is fed with SiO2-containing start material, the start material is softened in the crucible and, as a softened quartz glass mass, is drawn vertically downwards as a tubular quartz glass strand along a drawing axis through an annular gap between an outer member and an inner member, which is arranged in a through hole of the outer member, of a drawing nozzle provided in the bottom area of the crucible. To improve the known method with respect to less inhomogeneity in the drawn-off tubular strand and thereby to permit the manufacture of homogeneous, defect-free hollow cylinders of quartz glass by drawing from the melt, it is suggested according to the invention that the inner member of the drawing nozzle, viewed in the direction of the drawing axis, is held suspended and radially movable inside the through hole of the outer member, and that the annular gap of the drawing nozzle has a longitudinal section “L” in which its cross-sectional nozzle area is reduced in size from the top to the bottom.
摘要:
An ideal quartz glass for a wafer jig for use in an environment having an etching effect is distinguished by both high purity and high resistance to dry etching. To indicate a quartz glass that substantially fulfills these requirements, it is suggested according to the invention that the quartz glass is doped with nitrogen at least in a near-surface area, has a mean content of metastable hydroxyl groups of less than 30 wt ppm and that its fictive temperature is below 1250° C. and its viscosity is at least 1013 dPa·s at a temperature of 1200° C. An economic method for producing such a quartz glass comprises the following method steps: melting an SiO2 raw material to obtain a quartz glass blank, the SiO2 raw material or the quartz glass blank being subjected to a dehydration measure, heating the SiO2 raw material or the quartz glass blank to a nitriding temperature in the range between 1050° C. and 1850° C. in an ammonia-containing atmosphere, a temperature treatment by means of which the quartz glass of the quartz glass blank is set to a fictive temperature of 1250° C. or less, and a surface treatment of the quartz glass blank with formation of the quartz glass jig.