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:
Aug. 25, 2015
Filed:
Nov. 12, 2013
Sumco Corporation, Minato-ku, Tokyo, JP;
Takeshi Kadono, Minato-ku, JP;
SUMCO Corporation, Tokyo, JP;
Abstract
Provided is an epitaxial silicon wafer with reduced metal contamination achieved by higher gettering capability and a method of efficiently producing the same. The method of producing an epitaxial wafer includes a wafer production step of pulling a single crystal silicon ingot having a COP formation region by Czochralski process, and subjecting the obtained single crystal silicon ingot to slicing, thereby producing a silicon waferincluding COPs; a cluster ion irradiation step of irradiating the produced silicon waferwith cluster ionsto form a modifying layerformed from a constituent element of the cluster ions, contained as a solid solution in a surface portionA of the silicon wafer; and an epitaxial layer formation step of forming an epitaxial layeron the modifying layerof the silicon wafer