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:
Jul. 28, 2009
Filed:
Sep. 15, 2006
Shinichi Kohda, Kyoto, JP;
Shinichi Kohda, Kyoto, JP;
Rohm Co., Ltd., Kyoto-shi, JP;
Abstract
Processed traces are formed on at least a part of intended cutting lines A along which a wafer () where a nitride semiconductor lamination portion () is formed on a GaN based substrate () is divided into chips, by irradiating with a laser beam LB having a wavelength which is longer than the band gap wavelength of the GaN based substrateand an electrical field intensity which causes a multiple photons absorption, while adjusting the focal point to a constant depth d within the GaN based substrate () from the back surface of the wafer. After that, the wafer () is divided into chips along cutting starting points () which are formed in the vicinity of the processed traces by hitting with an impact. As a result, the wafer can be easily divided into chips, and in particular, end faces of a resonator can be formed with cleavage planes when an LD is formed.