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:
Jan. 27, 2009
Filed:
Jun. 17, 2005
Toyoki Kanzaki, Kyoto, JP;
Shu Yoshinaga, Kyoto, JP;
Toyoki Kanzaki, Kyoto, JP;
Shu Yoshinaga, Kyoto, JP;
Horiba, Ltd., Kyoto, JP;
Abstract
An apparatus for inspecting foreign matter on substrates on which circuit patterns, such as reticles or masks, are formed, reduces false detection due to scattered/diffracted light from circuit patterns and also reduces the occurrence of undetected foreign matters. A light source such as a scanning laser beam having a certain polarization angle to the surface of an inspection object substrate is provided. A main detector extinguishes scattered/diffracted light caused by a circuit pattern formed on the surface of the inspection substrate and detects an output signal. A reference detector transmits scattered/diffracted light caused by the circuit pattern, and detects an output signal. A signal processor calculates a difference signal by subtracting the intensity of a polarization component detected by the reference detector from the intensity of a polarization component detected by the main detector, and discriminates a signal with a large width caused by the circuit pattern and a signal with an acute peak caused by foreign matter.