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. 24, 2022
Filed:
May. 30, 2018
Hitachi High-tech Corporation, Tokyo, JP;
Akira Doi, Tokyo, JP;
Minoru Sasaki, Tokyo, JP;
Masaki Hasegawa, Tokyo, JP;
Hironori Ogawa, Tokyo, JP;
Tomohiko Ogata, Tokyo, JP;
Yuko Okada, Tokyo, JP;
HITACHI HIGH-TECH CORPORATION, Tokyo, JP;
Abstract
The present disclosure provides a wafer inspection technology that involves less degradation of the image quality even when an object to be observed has a variation in height due to warpage, etc. of a wafer. This wafer inspection apparatus obtains an image with less degradation by: adjusting the focal point of an observation optical system to a height measured by a height sensor for measuring wafer surface heights; and further, correcting a switching signal for a CCD line sensor on the basis of stage position data and optical magnification data corresponding to the height so as to make a correction corresponding to the wafer surface height.