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. 05, 2002
Filed:
Jan. 08, 1999
Chiwoei Wayne Lo, Campbell, CA (US);
Kenichi Kanai, Palo Alto, CA (US);
Schlumberger Technologies, Inc., Santa Clara, CA (US);
Abstract
Defects in a patterned substrate are detected by inspection with a charged particle beam inspection tool which generates an image of a portion of the patterned substrate and compares the image with a reference in order to identify any defects in the patterned substrate. Parameters of the tool are optimized to improve image uniformity and contrast, particularly voltage contrast. Prior to imaging an area of the substrate, the tool charges an area surrounding the image area to eliminate or reduce the effects caused by asymmetrical charging in the surrounding area. The tool alternates between charging the surrounding area and imaging the image area to produce a plurality of images of the image area, which are then averaged. The result is a highly uniform image with improved contrast for accurate defect detection.