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. 23, 2021
Filed:
Dec. 07, 2017
Sic wafer defect measuring method, reference sample, and method of manufacturing sic epitaxial wafer
Applicant:
Showa Denko K.k., Tokyo, JP;
Inventor:
Koji Kamei, Chichibu, JP;
Assignee:
SHOWA DENKO K.K., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C30B 25/04 (2006.01); G01N 21/64 (2006.01); C30B 29/06 (2006.01); C30B 29/36 (2006.01); G01N 21/95 (2006.01); G01N 21/956 (2006.01); H01L 21/02 (2006.01); H01L 21/67 (2006.01);
U.S. Cl.
CPC ...
G01N 21/6489 (2013.01); C30B 25/04 (2013.01); C30B 29/06 (2013.01); C30B 29/36 (2013.01); G01N 21/9501 (2013.01); G01N 21/95607 (2013.01); H01L 21/02529 (2013.01); H01L 21/67288 (2013.01);
Abstract
A SiC wafer defect measuring method which includes a device management step of managing a defect measuring device by irradiating a reference sample made of a material having a light-emitting intensity that does not change with repeated irradiation by excitation light and which has a pattern made of recesses and/or protrusions in the surface, the irradiation by the excitation light being performed before measuring defects in a SiC wafer and under the same irradiation conditions as the measurement of the defects in the SiC wafer, and then measuring the S/N ratio of the pattern from a reflection image of the pattern.