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. 22, 2025
Filed:
Apr. 06, 2021
Hitachi High-tech Corporation, Tokyo, JP;
Toshifumi Honda, Tokyo, JP;
Takeru Utsugi, Tokyo, JP;
HITACHI HIGH-TECH CORPORATION, Tokyo, JP;
Abstract
A defect inspection apparatus that includes a differential interference contrast illumination system that irradiates a sample surface with an illumination spot set composed of two polarized illumination spots that have different phases at a predetermined wavelength and that are offset by a predetermined shear amount, a differential interference contrast detection system that condenses reflected light beams of the two polarized illumination spots reflected from the sample surface to generate interference light beams, a scanning unit that scans the sample surface using the two polarized illumination spots, a sensor unit that photoelectrically converts the interference light beams generated by the differential interference contrast detection system to generate interference signals, a height displacement measurement unit that processes the interference signals to measure height displacement between the illumination spots, and a height shape reconstruction unit that accumulates height displacement data of the illumination spots and reconstructs a height shape of the sample surface.