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:
Jun. 19, 2018
Filed:
Apr. 21, 2015
Hitachi High-technologies Corporation, Tokyo, JP;
Hitachi High-Technologies Corporation, Tokyo, JP;
Abstract
For scanning electron beams and measuring overlay misalignment between an upper layer pattern and a lower layer pattern with high precision, electron beams are scanned over a region including a first pattern and a second pattern of a sample, the sample having the lower layer pattern (the first pattern) and the upper layer pattern (the second pattern) formed in a step after a step of forming the first pattern. The electron beams are scanned such that scan directions and scan sequences of the electron beams become axial symmetrical or point-symmetrical in a plurality of pattern position measurement regions defined within the scan region for the electron beams, thereby reducing measurement errors resulting from the asymmetry of electric charge.