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:
Aug. 24, 2010
Filed:
Feb. 04, 2008
Akifumi Kamijima, Tokyo, JP;
Hideyuki Yatsu, Tokyo, JP;
Hitoshi Hatate, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
An alignment method of mask patterns includes forming a first layer by transferring a first mask pattern onto a wafer, forming a second layer by transferring a second mask pattern onto the first layer, and particularly a first alignment step, forming the first layer, which performs alignment for minimizing offset between a center position of the wafer and a center position of the first mask pattern and a residual rotation error between the wafer and the first mask pattern and additional alignment for compensating an amount of possible deviation of superposition of the second layer pattern on the first layer pattern, and a second alignment step, forming the second layer, which performs only alignment for minimizing offset between a center position of the first layer pattern and a center position of the second mask pattern and a residual rotation error between the first layer pattern and the second mask pattern.