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:
Apr. 26, 2022
Filed:
Dec. 03, 2018
Applicant:
Showa Denko K.k., Tokyo, JP;
Inventors:
Yoshitaka Nishihara, Chichibu, JP;
Koji Kamei, Chichibu, JP;
Assignee:
SHOWA DENKO K.K., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/02 (2006.01); H01L 21/66 (2006.01); C30B 29/00 (2006.01); G01N 21/64 (2006.01); G01N 21/95 (2006.01); G01N 21/84 (2006.01);
U.S. Cl.
CPC ...
H01L 22/12 (2013.01); C30B 29/00 (2013.01); G01N 21/6489 (2013.01); G01N 21/9501 (2013.01); H01L 21/02378 (2013.01); H01L 21/02529 (2013.01); G01N 2021/8461 (2013.01); G01N 2021/8477 (2013.01);
Abstract
An evaluation method of a SiC epitaxial wafer includes: a first observation step of preparing a SiC epitaxial wafer having a high-concentration epitaxial layer having an impurity concentration of 1×10cmor more, irradiating a surface of the high-concentration epitaxial layer having an impurity concentration of 1×10cmor more with excitation light, and observing a surface irradiated with the excitation light via a band-pass filter having a wavelength band of 430 nm or less.