Abstract: A method for determining the refractive index profile of a preform is provided.

Abstract: A method for producing synthetic quartz glass by fusion of SiO2 granulate involves synthesizing amorphous SiO2 primary particles, granulating the amorphous SiO2 primary particles to form an open-pore SiO2 granulate, sintering the open-pore SiO2 granulate by heating in a sintering atmosphere at a sintering temperature and for a sintering period to form a densified SiO2 granulate, and melting the densified SiO2 granulate at a melting temperature to form the synthetic quartz glass. To provide an inexpensive production of low-bubble transparent components of quartz glass despite the use of still open-pore SiO2 granulate, the sintering atmosphere, sintering temperature and sintering duration are adjusted such that the densified SiO2 granulate still comprises open pores but manifests a material-specific infrared transmission T1700 at a wavelength of 1700 nm. This transmission is in the range of 50-95% of the infrared transmission T1700 of quartz glass granules of the same material.

Abstract: A method for determining the refractive index profile of a preform is provided.

Abstract: An optical component made of synthetic quartz glass includes a glass structure substantially free of oxygen defect sites and having a hydrogen content of 0.1×1016 to 1.0×1018 molecules/cm3, an SiH group content of less than 2×1017 molecules/cm3, a hydroxyl group content of 0.1 to 100 wt. ppm, and an Active temperature of less than 1070° C. The optical component undergoes a laser-induced change in the refractive index in response to irradiation by a radiation with a wavelength of 193 nm using 5×109 pulses with a pulse width of 125 ns and a respective energy density of 500 ?J/cm2 at a pulse repetition frequency of 2000 Hz. The change totals a first measured value M193 nm when measured using the applied wavelength of 193 nm and a second measured value M633 nm when measured using a measured wavelength of 633 nm. The ratio M193 nm/M633 nm is less than 1.7.

Abstract: An optical component made of synthetic quartz glass includes a glass structure substantially free of oxygen defect sites and having a hydrogen content of 0.1×1016 to 1.0×1018 molecules/cm3, an SiH group content of less than 2×1017 molecules/cm3, a hydroxyl group content of 0.1 to 100 wt. ppm, and an Active temperature of less than 1070° C. The optical component undergoes a laser-induced change in the refractive index in response to irradiation by a radiation with a wavelength of 193 nm using 5×109 pulses with a pulse width of 125 ns and a respective energy density of 500 ?J/cm2 at a pulse repetition frequency of 2000 Hz. The change totals a first measured value M193 nm when measured using the applied wavelength of 193 nm and a second measured value M633 nm when measured using a measured wavelength of 633 nm. The ratio M193 nm/M633 nm is less than 1.7.

Abstract: On the basis of a known method for producing a blank of titanium-doped glass with a high silica content (glass) for a mirror substrate for use in EUV lithography which has a surface region that has an outer contour, is intended to be provided with a reflective coating and is specified as a highly loaded zone when the mirror substrate is used as intended, in order to provide a blank which can be produced at low cost and nevertheless meets high requirements with respect to homogeneity and freedom from blisters and striae, a procedure which comprises the following method steps is proposed: (a) producing a front body of titanium-doped high-quality glass with dimensions more than large enough to enclose the outer contour, (b) producing a cylindrical supporting body from titanium-doped glass, (c) bonding the front body and the supporting body to form a composite body, and (d) working the composite body to form the mirror substrate blank, wherein the step of producing the front body comprises a homogenizing process

Abstract: A method for producing synthetic quartz glass by fusion of SiO2 granulate involves synthesizing amorphous SiO2 primary particles, granulating the amorphous SiO2 primary particles to form an open-pore SiO2 granulate, sintering the open-pore SiO2 granulate by heating in a sintering atmosphere at a sintering temperature and for a sintering period to form a densified SiO2 granulate, and melting the densified SiO2 granulate at a melting temperature to form the synthetic quartz glass. To provide an inexpensive production of low-bubble transparent components of quartz glass despite the use of still open-pore SiO2 granulate, the sintering atmosphere, sintering temperature and sintering duration are adjusted such that the densified SiO2 granulate still comprises open pores but manifests a material-specific infrared transmission T1700 at a wavelength of 1700 nm. This transmission is in the range of 50-95% of the infrared transmission T1700 of quartz glass granules of the same material.

Abstract: A known method for producing synthetic quartz glass comprises: (a) reacting a carbonic silicon compound-containing raw material with oxygen in a reaction zone into SiO2 particles, (b) precipitating the SiO2 particles on a sedimentation area by forming a porous SiO2 soot body containing hydrogen and hydroxyl groups, (c) drying the porous SiO2 soot body, and (d) glazing to the synthetic quartz glass by heating the soot body up to a glazing temperature. In order to facilitate cost-efficient production of quartz glass by means of pyrolyzing or hydrolyzing a carbon-containing silicon compound using a carbon-containing raw material, the invention describes the production of a soot body with a carbon content within the range of 1 ppm by weight to 50 ppm by weight.

Abstract: An optical component made of synthetic quartz glass includes a glass structure substantially free of oxygen defect sites and having a hydrogen content of 0.1×1016 to 1.0×1018 molecules/cm3, an SiH group content of less than 2×1017 molecules/cm3, a hydroxyl group content of 0.1 to 100 wt. ppm, and an Active temperature of less than 1070° C. The optical component undergoes a laser-induced change in the refractive index in response to irradiation by a radiation with a wavelength of 193 nm using 5×109 pulses with a pulse width of 125 ns and a respective energy density of 500 ?J/cm2 at a pulse repetition frequency of 2000 Hz. The change totals a first measured value M193nm when measured using the applied wavelength of 193 nm and a second measured value M633nm when measured using a measured wavelength of 633 nm. The ratio M193nm/M633nm is less than 1.7.

Abstract: On the basis of a known method for producing a blank of titanium-doped glass with a high silica content (glass) for a mirror substrate for use in EUV lithography which has a surface region that has an outer contour, is intended to be provided with a reflective coating and is specified as a highly loaded zone when the mirror substrate is used as intended, in order to provide a blank which can be produced at low cost and nevertheless meets high requirements with respect to homogeneity and freedom from blisters and striae, a procedure which comprises the following method steps is proposed: (a) producing a front body of titanium-doped high-quality glass with dimensions more than large enough to enclose the outer contour, (b) producing a cylindrical supporting body from titanium-doped glass, (c) bonding the front body and the supporting body to form a composite body, and (d) working the composite body to form the mirror substrate blank, wherein the step of producing the front body comprises a homogenizing process

Abstract: On the basis of a known method for producing a blank of titanium-doped glass with a high silica content (glass) for a mirror substrate for use in EUV lithography which has a surface region that has an outer contour, is intended to be provided with a reflective coating and is specified as a highly loaded zone when the mirror substrate is used as intended, in order to provide a blank which can be produced at low cost and nevertheless meets high requirements with respect to homogeneity and freedom from blisters and striae, a procedure which comprises the following method steps is proposed: (a) producing a front body of titanium-doped high-quality glass with dimensions more than large enough to enclose the outer contour, (b) producing a cylindrical supporting body from titanium-doped glass, (c) bonding the front body and the supporting body to form a composite body, and (d) working the composite body to form the mirror substrate blank, wherein the step of producing the front body comprises a homogenizing process

Abstract: A known method for producing synthetic quartz glass comprises: (a) reacting a carbonic silicon compound-containing raw material with oxygen in a reaction zone into SiO2 particles, (b) precipitating the SiO2 particles on a sedimentation area by forming a porous SiO2 soot body containing hydrogen and hydroxyl groups, (c) drying the porous SiO2 soot body, and (d) glazing to the synthetic quartz glass by heating the soot body up to a glazing temperature. In order to facilitate cost-efficient production of quartz glass by means of pyrolysing or hydrolysing a carbon-containing silicon compound using a carbon-containing raw material, the invention describes the production of a soot body with a carbon content within the range of 1 ppm by weight to 50 ppm by weight.

Abstract: On the basis of a known method for producing a blank of titanium-doped glass with a high silica content (glass) for a mirror substrate for use in EUV lithography which has a surface region that has an outer contour, is intended to be provided with a reflective coating and is specified as a highly loaded zone when the mirror substrate is used as intended, in order to provide a blank which can be produced at low cost and nevertheless meets high requirements with respect to homogeneity and freedom from blisters and striae, a procedure which comprises the following method steps is proposed: (a) producing a front body of titanium-doped high-quality glass with dimensions more than large enough to enclose the outer contour, (b) producing a cylindrical supporting body from titanium-doped glass, (c) bonding the front body and the supporting body to form a composite body, and (d) working the composite body to form the mirror substrate blank, wherein the step of producing the front body comprises a homogenizing process

Abstract: The present invention relates to a quartz glass blank for an optical component for transmitting radiation of a wavelength of 15 nm and shorter, the blank consisting of highly pure quartz glass, doped with titanium and/or fluorine, which is distinguished by an extremely high homogeneity. The homogeneity relates to the following features: a) micro-inhomogeneities caused by a local variance of the TiO2 distribution (<0.05% TiO2, averaged over a volume element of (5 ?m)3 in relation to the mean value of the TiO2 content), b) an absolute maximum inhomogeneity in the thermal expansion coefficient ?? in the main functional direction (<5 ppb/K), c) a radial variance of the thermal expansion coefficient over the usable surface of the quartz glass blank of not more than 0.4 ppb/(K.cm); d) a maximum stress birefringence (SDB) at 633 nm in the main functional direction of 2 nm/cm with a specific progression; and e) a specific progression of the ??, averaged according to (b) on the optical surface.

Abstract: To optimize an optical component of synthetic quartz glass, in the case of which a quartz glass blank is subjected to a multistage annealing treatment, with respect to compaction and central birefringence, the present invention suggests a method comprising the following steps: (a) a first treatment phase during which the quartz glass blank is treated in an upper temperature range between 1130° C. and 1240° C., (b) cooling the quartz glass blank at a first-higher-mean cooling rate to a quenching temperature below 1100° C., a fictive temperature with a high mean value of 1100° C. or more being reached in the quartz glass, (c) a second treatment phase which comprises cooling of the quartz glass blank at a second-lower-mean cooling rate, and in which the quartz glass blank is treated in a lower temperature range between 950° C. and 1100° C. such that a fictive temperature is reached in the quartz glass with a low mean value which is at least 50° C.

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: 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.

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 known method for producing synthetic quartz glass with a predetermined hydroxyl group content comprises the following steps: a porous SiO2 soot body is produced by flame hydrolysis or oxidation of a silicon-containing start compound and by layerwise deposition of SiO2 particles on a rotating support; the soot body is subjected to a dehydration treatment in a reaction gas-containing drying atmosphere at a drying temperature for removing hydroxyl groups; and the SiO2 soot body is vitrified into a body consisting of the synthetic quartz glass. Starting from this, and in order to permit a reproducible and reliable manufacture of synthetic, UV-radiation resistant quartz glass with predetermined hydroxyl group content and low chlorine content, it is suggested according to the invention that the dehydration treatment according to method step (b) comprises a drying phase during which ozone is used as the reaction gas, whereby the ozone content of the drying atmosphere is between 0.5% by vol. and 10% by vol.

Abstract: To provide an optical component of quartz glass for use in a projection objective for immersion lithography at an operating wavelength below 250 nm, which component is optimized for use with linearly polarized UV laser radiation and particularly with respect to compaction and birefringence induced by anisotropic density change, it is suggested according to the invention that the quartz glass should contain hydroxyl groups in the range of from 1 wtppm to 60 wtppm and chemically bound nitrogen, and that the mean hydrogen content of the quartz glass should be in the range of 5×1015 molecules/cm to 1×1017 molecules/cm3.