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:
Feb. 03, 2015
Filed:
Feb. 02, 2010
Kenji Oka, Hitachinaka, JP;
Kenji Mitomo, Hitachinaka, JP;
Kenichiro Komeda, Kumamoto, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
While an illumination optical system is irradiating the surface of a contaminated standard wafer with illumination light, this illumination light is scanned over the surface of the contaminated standard wafer, then detectors of a detection optical system each detect the light scattered from the surface of the contaminated standard wafer, next a predefined reference value in addition to detection results on the scattered light is used to calculate a compensation parameter 'Comp' for detection sensitivity correction of photomultiplier tubes of the detectors, and the compensation parameter 'Comp' is separated into a time-varying deterioration parameter “P”, an optical characteristics parameter “Opt”, and a sensor characteristics parameter “Lr”, and correspondingly managed. This makes is easy to calibrate the detection sensitivity.