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:
Feb. 25, 2014
Filed:
Jan. 28, 2011
Kazunari Kurita, Tokyo, JP;
Kazunari Kurita, Tokyo, JP;
Sumco Corporation, Tokyo, JP;
Abstract
An object of the present invention is to provide a method of producing a silicon wafer and a method of producing an epitaxial wafer, which enable easily forming a gettering site in a relatively short period of time and effectively suppressing occurrence of dislocation induced by internal stresses. Specifically, the present invention provides a method of producing a silicon wafer, comprising: irradiating a first laser beam having a relatively long wavelength and a second laser beam having a relatively short wavelength onto a portion of a silicon wafer located at a predetermined depth measured from a surface of the silicon wafer, wherein the first laser beam is concentrated at a portion located at a predetermined depth of the wafer to form a process-affected layer for gettering heavy metals thereat, the second laser beam is concentrated at a beam-concentration portion in the vicinity of the surface of the wafer to melt the beam-concentration portion, the beam-concentration portion is then recrystallized.