The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 29, 2016
Filed:
May. 07, 2013
Wacker Chemie Ag, Munich, DE;
Wacker Chemie AG, Munich, DE;
Abstract
Granular polycrystalline silicon includes a compact matrix including radiating acicular crystal aggregates of crystal size from 0.001-200 μm. A process for producing granular polycrystalline silicon includes producing granular silicon in a fluidized bed reactor from a gas mixture containing TCS (20-29 mol %) and hydrogen at a fluidized bed temperature of 900-970° C., dividing the granular silicon in a screen system having at least one screen deck into at least two screen fractions, the smallest screen fraction being ground in a grinding system to give seed particles having a size of 100-1500 μm and a mass-based median value from 400 to 900 μm, and these seed particles being supplied to fluidized bed reactor, and a further screen fraction being supplied to a fluidized bed reactor, and being surface-treated with a gas mixture containing TCS (5.1-10 mol %) and hydrogen at a fluidized bed temperature of 870-990° C.