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:
Apr. 12, 2005
Filed:
Aug. 01, 2001
Yasuhiro Koizumi, Tokyo, JP;
Shiaki Murai, Tokyo, JP;
Shigeru Noguchi, Tokyo, JP;
Katsuhide Tsuchiya, Tokyo, JP;
Yasuhiro Koizumi, Tokyo, JP;
Shiaki Murai, Tokyo, JP;
Shigeru Noguchi, Tokyo, JP;
Katsuhide Tsuchiya, Tokyo, JP;
Dai Nippon Printing Co., Ltd., Tokyo, JP;
Abstract
The present invention relates to a defect inspection apparatus for a phase shift mask that is capable of detecting phase shifter defects that cannot be detected by conventional inspection techniques, by a simple method using an optical method and a comparison of electric signals. In a defect inspection apparatus for a phase shift mask having a phase shifter pattern provided on a mask transparent substrate, after the phase shifter pattern has been formed, a phase shifter defect inspection is performed from the mask transparent substrateside of the phase shift mask. To perform the defect inspection, lightis applied to the phase shift maskfrom the mask transparent substrateside thereof, and reflection images of at least two different phase shifter pattern fabricated regions are captured by photoelectric conversion light-receiving elementsand. The respective image signalsandof the reflection images are compared with each other to detect a defect on the mask from the difference between the signals.