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. 02, 2024
Filed:
Jun. 03, 2020
Disco Corporation, Tokyo, JP;
Ryohei Yamamoto, Tokyo, JP;
Shuichi Torii, Tokyo, JP;
DISCO CORPORATION, Tokyo, JP;
Abstract
A method for manufacturing an SiC wafer from an SiC ingot includes a verifying step of applying a test laser beam to the SiC ingot in a predetermined area with the focal point of the test laser beam set inside the SiC ingot at a predetermined depth from the end surface of the SiC ingot. The test laser beam has a transmission wavelength to SiC, thereby forming a test separation layer inside the SiC ingot at the predetermined depth. The test separation layer has a test modified portion where SiC is decomposed into Si and C and test cracks extend from the test modified portion along a c-plane in the SiC ingot. Whether or not the test cracks have been properly formed is verified. When verifying, the power of the test laser beam is changed to set a proper power at which the test cracks are properly formed.