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:
May. 11, 1999
Filed:
Apr. 08, 1996
Yasuo Yatsugake, Saitama-ken, JP;
Takashi Okawa, Fujioka, JP;
Norihiko Mizutani, Saitama-ken, JP;
Shigeharu Iizuka, Honjo, JP;
Hitachi Electronics Engineering, Co., Ltd., Tokyo, JP;
Abstract
A wafer surface inspection method and device including a low angle light receiving system having an elevation angle less than 30.degree. with reference to the wafer surface, and a high angle light receiving system having an elevation angle equal to or larger than 30.degree., scans the wafer with a laser beam, receives scattered light to perform extraneous substance detection in response to the scanning, and detects wafer defects only by the high angle light receiving system, and sticking extraneous substances by either the low angle receiving system or by both the low angle light receiving system and the high angle light receiving system.