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:
Nov. 12, 2002
Filed:
Mar. 18, 1999
Shinroku Maejima, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A semiconductor device having a registration accuracy measurement mark allows measurement in registration to be within an allowable measurement error even if there is a difference in height between a master pattern and a pattern of the registration accuracy measurement mark. The width of the second layer registration accuracy measurement mark pattern formed as a line is made larger than that of the second layer master pattern formed as a line by 0.85 &mgr;m to 1.0 &mgr;m. Accordingly, the difference in the amount of offset due to aberration upon transfer of the patterns between the second layer master pattern and the second layer registration accuracy measurement mark pattern can be within an allowable range in the overlay measurement. In addition, even if the second layer registration accuracy measurement mark pattern and the second layer master pattern are formed to have a difference in height (maximum 0.6 &mgr;m), the depth of focus (1.2 &mgr;m) is ensured.