Title:
改良された位相欠陥感度のためのデフォーカスを利用する差分検出器
Document Type and Number:
Japanese Patent JP4666919
Kind Code:
B2
Abstract:
Provided are apparatus and methods for detecting phase defects. The invention relies generally on the distortion of light as it passes through defects in phase shift masks to detect these defects. Light traveling through a defect, such as a bump in an etched area will travel at a different rate than light traveling through air. In order to enhance the signals generated from the defects, the invention in several embodiments provides a defocused light inspection beam by setting the focus of the beam to a level above or below the photomask subject to inspection. The light from the photomask is collected by a detector split into at least two portions, each generating a signal. A resulting differential signal produced from the signals generated at each of the two detector portions is used to determine whether a defect in the photomask is present, in one embodiment, by generating an image from the resulting signal.
More Like This:
Inventors:
Kranz Matthias Sea.
Pettybone Donald W.
Kvam Damon Ef.
Stokovsky Stan
Pettybone Donald W.
Kvam Damon Ef.
Stokovsky Stan
Application Number:
JP2003558900A
Publication Date:
April 06, 2011
Filing Date:
December 24, 2002
Export Citation:
Assignee:
KLA-TENCOR CORPORATION
International Classes:
G01N21/896; G01N21/956; G03F1/84; G03F7/20; H01L21/027
Domestic Patent References:
| JP4328549A | ||||
| JP54005750A | ||||
| JP9230247A | ||||
| JP5165197A | ||||
| JP6273916A |
Attorney, Agent or Firm:
Meisei International Patent Office