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:
Nov. 12, 2002
Filed:
Aug. 31, 2001
Alleppey V. Hariharan, Nashua, NH (US);
Mohan Chandra, Merrimack, NH (US);
Michael Costantini, Hudson, NH (US);
Yuepeng Wan, Nashua, NH (US);
G.T. Equipment Technologies, Inc., Nashua, NH (US);
Abstract
A thermodynamically stable, protective coating layer is applied by thermal spray technique to the inner and outer surfaces of a quartz crucible used for mono or polycrystalline silicon crystallization processing, inhibiting fusion between the silicon melt and the vitreous silica of the crucible, contamination of the silicon melt by contaminants released from the crucible by devitrification, and any chemical reaction occurring between the crucible and any supporting graphite structure. A powdered form of a suitable protective coating material compatible with high temperature plasma spray techniques, such as magnesium zirconate, barium zirconate, or stabilized zirconium oxide, is fed into a high temperature and high speed plasma jet directed at the crucible. The powder particles are softened or melted in the jet and deposited on the surfaces of the quartz crucible, and allowed to cool and harden into a protective coating.