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:
Aug. 04, 1998
Filed:
Sep. 27, 1996
Hisashi Masumura, Nishigou-mura, JP;
Hideo Kudo, Nishigou-mura, JP;
Shingo Sumie, Kobe, JP;
Hidetoshi Tsunaki, Kobe, JP;
Yuji Hirao, Kobe, JP;
Noritaka Morioka, Kobe, JP;
Shin-Etsu Handotai Co., Ltd., Tokyo, JP;
Abstract
The invention seeks to permit evaluation of edge portion of like inclined surfaces of wafer with high accuracy without the conventional destruction process based on the selective etching process but with the contact-free, non-destructive and high accuracy optical acoustical process. To this end, the invention features determination of residual damages as crystal damages caused to wafer edge in an optical acoustical process, which comprises the steps of causing a measurement probe to face each of three exciting laser beam irradiation points on upper and lower inclined surfaces and at an accurate end of an edge portion of a semiconductor wafer, and determining a thermal response induced by the exciting laser beam by a laser interference process.