Wacker Chemie Ag

Coltène/whaledent Gmbh + Co. Kg

Barbara Mueller

Werner Mannschedel

Walter Haeckl

Martin Schlueter

Johannes Wolfert

Michael Stepp

Heinz Kraus

Laszlo Fabry

Mikhail Sofin

Robert Ring

Wolfgang Stoiber

Thomas Koch

Elmar Monz

A process for producing polysilicon, includes a) depositing polycrystalline silicon on filaments using reaction gas containing silicon-containing component (SCC) containing trichlorosilane, and hydrogen, wherein molar saturation of SCC based on hydrogen is at least 25%; b) feeding offgas from the deposition into a cooling apparatus, i) wherein condensed offgas components containing SiClare conducted to an apparatus which enables distillative purification of the condensate, and ii) non-condensing components are conducted to an adsorption or desorption unit; c) obtaining a first stream of non-condensing components purified by adsorption and containing hydrogen; and d) obtaining, during adsorption unit regeneration, a second stream of non-condensing components, containing SiClwhich is then preferably supplied to a converter for conversion of SiClto trichlorosilane. A process for depositing polysilicon on filaments with a reaction gas includes a SCC and hydrogen, wherein molar saturation of SCC based on hydrogen is at least 25%.

Process for producing polysilicon

Bottle holder for a modular filling station for filling syringes

Modular filling station for filling syringes

Installation of a shield around a Siemens reactor prior to harvesting polysilicon rods produced therein allows the upper, bell jar-like shell to be removed for cleaning, while protecting the polysilicon rods from contamination and increasing safety of nearby personnel. The polysilicon rods are harvested while the shield is present.

Process for producing polycrystalline silicon

The Siemens process for deposition of polycrystalline silicon in the form of rods in a sealed reactor is improved by, after introduction of deposition gas has ceased, introducing a ventilating gas into the partially sealed reactor, withdrawing a gas stream from the reactor, and monitoring the components in the gas stream withdrawn until a desired concentration of one or more components is reached, and opening the reactor to remove the rods.

Reactive depletion of reactor deposits in harvesting polycrystalline silicon rods

The content of phosphorus in polycrystalline silicon prepared by the Siemens process is reduced by treating phosphorus-containing steel surfaces with an &#x3b1;-amino-functional alkoxysilane. The treated surface exhibits less corrosion in an atmosphere of moist hydrogen chloride, and less loss of phosphorus as a result.

Treatment of steel surfaces

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Burgkirchen, Germany

Barbara Mueller