Heraeus Quarzglas Gmbh & Co Kg

W.c. Heraeus Gmbh

Heraeus Quarzglas Gmbh

Heraeus Quarzschmelze Gmbh

Heraeus Elektroden Gmbh

Waltraud Werdecker

Fritz Aldinger

Johann Leist

Rolf Gerhardt

Juergen Weber

Udo Gertig

Norbert Traeger

Heinz Fabian

Christian Schenk

Bodo Kuehn

Gerrit Scheich

Jürgen Weber

Rainer Koeppler

Ulrich Kirst

Rolf G&ouml;bel

Martin Trommer

Walter Lehmann

Stefan Ochs

Jörg Becker

Richard Keilberth

Wolfgang Englisch

Martin Kutzner

Helmut Leber

Peter Fabian

Rolf Bruning

Bruno Uebbing

Hartwig Schaper

Wolfgang Stang

Armin Maul

Thorsten Herbert

Joachim Peekhaus

Joerg Becker

Werner Ponto

Rainer K&ouml;ppler

Wolfgang Krock

Norbert Cibis

Poul-Erik Breidenbach

Harry Heinke

Franz Schreiber

Dieter Brunner

Tobias Pogge

Kerstin Meyer-Merget

Sebastian Pankalla

Erich Rosin

Thilo Braemer

Maximilian Kara

Roland Horn

The invention relates to a process for producing a paste-like SiOcomposition using an SiOslip which allows simple intermediate storage and transport conditions without the processability of the slip to give the paste-like SiOcomposition being impaired thereby. According to the invention, it is for this purpose proposed that a homogeneous SiObase slip be subjected to a drying step to form a dry SiOcomposition and subsequently be processed further by means of a remoistening step to give the paste-like SiOcomposition, where the remoistening step comprises the addition of liquid to the dry SiOcomposition to form a paste-like kneadable SiOcomposition having a solids content of more than 85% by weight. The invention further relates to the use of a paste-like SiOcomposition as repair composition.

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In a known method, a SiOslip layer is applied to a basic quartz glass body by means of spraying on an SiOslip, the slip layer is dried and sintered to form an SiO-containing functional layer. In order to permit the reproducible production of a functional quartz glass layer, even in the case of surfaces that are curved or inclined with respect to the vertical, having high layer thicknesses which satisfy high requirements on the layer homogeneity, the invention proposes that the slip contain the following components in a dispersion liquid: splintery, amorphous SiOgranules having a gain size distribution having a Dvalue in the range of 3 &#x3bc;m to 30 &#x3bc;m and having a proportion by weight of at least 10% by weight, based on the total solids content; spherical, amorphous SiOparticles having a particle size distribution having a Dvalue in the range of 1 &#x3bc;m to 50 &#x3bc;m and having a proportion by weight of at least 30% by weight, based on the total solids content; SiOnano particles having particle sizes of less than 100 nm and having a proportion by weight between 0.2% and 10% by weight, based on the total solids content; and a non-ionic, alkali-free surfactant having a proportion in the range of 0.005 to 0.5%, based on the volume of the dispersion liquid.

Method for producing a coated quartz glass component

To optimize a known method for producing a composite body from a basic body of opaque quartz glass and a dense sealing layer, in such a way that the basic body can be provided with the dense sealing layer without any significant changes and deformations in the opaque material being noticed, the invention suggests a method comprising the following steps: (a) producing the basic body by using a first slip which contains larger amorphous SiOparticles; (b) providing a second slip which contains smaller amorphous SiOparticles and the composition of which differs from that of the first slip at least in that it contains SiOnanoparticles in the range between 0.2% by wt. to 15% by wt. and which is distinguished by a relatively low vitrification temperature; (d) producing a slip layer from the second slip on a surface of the basic body, drying the slip layer, and (e) subsequently vitrifying the slip layer with formation of the dense sealing layer.

Method for the production of a composite body from a basic body of opaque quartz glass and a tight sealing layer

SiOslurry for the production of quartz glass contains a dispersion liquid and amorphous SiOparticles with particle sizes to a maximum of 500 &#x3bc;m. The largest volume fraction is SiOparticles with particle sizes of 1 &#x3bc;m-60 &#x3bc;m, as well as SiOnanoparticles with particle sizes less than 100 nm constituting 0.2-15% volume by weight of the entire solids content. To prepare the slurry for use and optimize its flow behavior for later processing by dressing or pouring the slurry mass, and for later drying and sintering without cracks, the slurry has SiOparticles with a multimodal distribution of particle sizes, with a first maximum in the range 1 &#x3bc;m-3 &#x3bc;m and a second maximum in the range 5 &#x3bc;m-50 &#x3bc;m, and an 83%-90% solids content by weight of the SiOparticles and the SiOnanoparticles together.

A known SiOslurry for the production of quartz glass contains a dispersion liquid and amorphous SiOparticles with particle sizes to a maximum of 500 &#x3bc;m, wherein the largest volume fraction is composed of SiOparticles with particle sizes in the range 1 &#x3bc;m-60 &#x3bc;m, as well as SiOnanoparticles with particle sizes less than 100 nm in the range 0.2-15% volume by weight (of the entire solids content). In order to prepare such a slurry for use, and to optimize the flow behavior of such a slurry with regard to later processing by dressing or pouring the slurry mass, and with regard to later drying and sintering without cracks, the invention suggests a slurry with SiOparticles with a multimodal distribution of particle sizes, with a first maximum of the sizes distribution in the range 1 &#x3bc;m-3 &#x3bc;m and a second maximum in the range 5 &#x3bc;m-50 &#x3bc;m, and a solids content (percentage by weight of the SiOparticles and the SiOnanoparticles together) in the range 83%-90%.

Methods for producing a quartz glass component with reflector layer are known in which a reflector layer composed of quartz glass acting as a diffuse reflector is produced on at least part of the surface of a substrate body composed of quartz glass. In order, taking this as a departure point, to specify a method which enables cost-effective and reproducible production of uniform SiOreflector layers on quartz glass components, it is proposed according to the invention that the reflector layer is produced by thermal spraying by means of SiOparticles being fed to an energy carrier, being incipiently melted or melted by means of said energy carrier and being deposited on the substrate body. In the case of a quartz glass component obtained according to the method, the SiOreflector layer is formed as a layer which is produced by thermal spraying and has an opaque effect and which is distinguished by freedom from cracks and uniformity.

Quartz glass component with reflector layer and method for producing the same

In a known method for bonding components made of material with a high silicic acid content by means of a substance to substance bond, a SiO-containing bonding mass is formed between connecting surfaces of the components. In order to provide for cost-efficient manufacture of a thermally stable composite, the invention proposes to generate a SiO-containing bonding mass that is generic with regard to the material with a high silicic acid content, comprising the following procedural steps: provision of a slurry containing amorphous SiOparticles; formation of a slurry mass between the connecting surfaces which are fixed in position with regard to each other; drying of the slurry mass; and solidification of the slurry mass by heating under formation of the SiO-containing bonding mass. A component assembly manufactured according to the method of the invention shows high temperature resistance and thermal fatigue resistance and can also be used in contamination-sensitive applications. The component assembly is characterized by an amorphous SiO-containing bonding mass, whose chemical composition is generic with regard to the material with the high silicic acid content of the basic material of the components, whereby the specific density of the SiO-containing bonding mass is at least 2.0 g/cm.

Method for bonding components made of material with a high silicic acid content

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&#xb0; C. and its viscosity is at least 10dPa&#xb7;s at a temperature of 1200&#xb0; C. An economic method for producing such a quartz glass comprises the following method steps: melting an SiOraw material to obtain a quartz glass blank, the SiOraw material or the quartz glass blank being subjected to a dehydration measure, heating the SiOraw material or the quartz glass blank to a nitriding temperature in the range between 1050&#xb0; C. and 1850&#xb0; 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&#xb0; C. or less, and a surface treatment of the quartz glass blank with formation of the quartz glass jig.

Holder made from quartz glass for the processing of semiconductor wafers and method for production of the holder

The invention relates to a method for the economic production of a blank for a component made from laser-active quartz glass in any form or dimension. The method comprises the following method steps: a) preparation of a dispersion with a solids content of at least 40 wt. %, comprising SiOnanopowder and doping agents, including a cation of the rare earth metals and transition metals in a fluid, b) granulation by agitation of the dispersion, with removal of moisture to form a doped SiOgranulate of spherical porous granular particles with a moisture content of less than 35 wt. % and a density of at least 0.95 g/cm, c) drying and purification of the SiOgranulate, by heating to a temperature of at least 1000&#xb0; C. to form doped porous SiOgrains with an OH content of less than 10 ppm and d) sintering or fusing the doped SiOgrains in a reducing atmosphere to give the blank made from doped quartz glass.

Method for the production of laser-active quartz glass and use thereof

A process for manufacture of a component made of opaque synthetic quartz glass, and a quartz glass tube manufactured according to said process. The process comprises (i) providing a starting material in the form of granulated material of highly pure, synthetic SiO comprising at least partially porous agglomerates of SiO primary particles, the granulated material having a compacted bulk density of no less than 0.8 g/cm , (ii) filling the granulated material into a mold and converting it to an opaque quartz glass preform through a process of melting, and (iii) reshaping the preform in a heat reshaping process to obtain a component made of opaque quartz glass. A quartz glass tube is made of quartz glass consisting of a granulated material of synthetic SiO with a lithium content of no more than 100 wt-ppb, and the wall thickness of said component being in the range of 0.5 mm to 15 mm.

Process for manufacture of a component made of opaque synthetic quartz glass

In order to provide a quartz glass crucible distinguished by high purity, high opacity and/or low transmissibility in the IR spectrum, it is proposed on the basis of a known quartz glass crucible of opaque quartz glass with a crucible body symmetrical in relation to a rotational axis, an outer zone ( ) of opaque quartz glass transitioning radially toward the inside into an inner zone ( ) of transparent quartz glass and with a density of at least 2.15 g/cm , that according to the invention, the crucible body ( ) be made of a synthetic SiO granulate with a specific BET surface ranging from 0.5 m /g to 40 m /g, a tamped volume of at least 0.8 g/cm and produced from at least partially porous agglomerates of SiO primary particles. A process for producing a quartz glass crucible of this kind is distinguished according to the invention in that for the production of the crucible a SiO granulate is used which was formed from at least partially porous agglomerates of synthetically manufactured SiO primary particles and that it has a specific BET surface ranging from 0.5 m /g to 40 m /g and a tamped volume of at least 0.8 g/cm , the heating effected in such a way that a vitrification front advances from the inside outward while an inner zone ( ) of transparent quartz glass is being formed.

Quartz glass crucible and process for the production thereof

Composite material with high resistance to temperature changes and a high density, and having an SiO -containing matrix with quartz glass grains embedded therein is produced by preparing a suspension from a particle mixture of finely divided SiO powder having at least two different particle fractions and of the quartz glass grains, forming a green compact and sintering the compact. The matrix has an SiO content of at least 99% by wt. and is formed from at least first and second particle fractions, each of which is present as granules of nanoscale, amorphous, synthetically produced SiO primary particles having a mean primary particle size of less than 100 nm. The composite material has an SiO -containing matrix with an SiO content of at least 99% by wt. It is particularly suited for applications such as starting material for producing a permanent mold for melting solar silicon.

Method of producing a composite material having a high SiO2 content, composite material obtained according to the method, and permanent mold made thereof

Based on a known process for the manufacture of opaque quartz glass, by mixing SiO particles and an additive which is volatile at a melting temperature, forming a body and melting said body with an advancing melt front forming in the body, it is proposed according to the invention that in order to reduce the danger of contamination, a body ( ) be formed with an inner bore ( ) and be heated in such a manner that the melt front ( ) advances from the inner bore ( ) to the outside. The article of pure opaque quartz glass according to the invention has high resistance to temperature change, high mechanical strength and good chemical durability. It is distinguished by an opening ( ) enclosed by an inner wall ( ), with an inner SiO surface layer ( ) having a layer thickness ranging from 30 mm to 500 mm and a density of at least 2.15 g/cm .

Process for making opaque quartz glass and opaque component made according to the process

In a known process for the production of opaque quartz glass a blank is formed from synthetic SiO granulate and is heated at a vitrification temperature to form a body of opaque quartz glass. In order to provide on this basis a process for the production of pure opaque quartz glass with a homogenous pore distribution, high density, high viscosity and a low tendency to devitrify, it is proposed according to the invention that the SiO granulate to be used is a SiO granulate ( ) composed of at least partially porous agglomerates of SiO primary particles, with a specific BET surface ranging from 1.5 m /g to 40 m /g and an apparent density of at least 0.8 g/cm . A SiO granulate ( ) suitable for the implementation of the process is distinguished in that it is formed from at least partially porous agglomerates of SiO primary particles and in that it has a specific BET surface ranging from 1.5 m /g to 40 m /g and an apparent density of at least 0.6 g/cm .

Process for making opaque quartz, for carrying out the process suitable SiO2 granulate, and component of opaque quartz glass

In a process for manufacture of dense, amorphous quartz glass granulate by production of a porous granulate from amorphous SiO powder and vitrification of the granulate, a porous SiO granulate is exposed to a fuel gas flame and is finely dispersed, heated and vitrified therein. The fuel gas flame is more flexible as concerns adjustment of the temperature than in known processes. It is in particular possible to set higher temperatures. The granulate can be exposed to very high sintering temperatures in the fuel gas flame without sintering into agglomerates. At the same time, heat resistance problems of sintering containers such as furnaces and melting pots are avoided. In addition, contamination of the SiO granulate by contact with the walls of sintering or vitrifying containers is eliminated. The process makes it possible to economically produce a highly pure and dense quartz glass granulate.

Process for the manufacture of quartz glass granulate

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Hanau, Germany

Waltraud Werdecker