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:
Jan. 06, 2004
Filed:
Sep. 11, 2002
Applicant:
Inventors:
Pary Baluswamy, Boise, ID (US);
Tim H. Bossart, Boise, ID (US);
Assignee:
Micron Technology, Inc., Boise, ID (US);
Primary Examiner:
Int. Cl.
CPC ...
H01L 2/166 ; H01L 2/3544 ;
U.S. Cl.
CPC ...
H01L 2/166 ; H01L 2/3544 ;
Abstract
In the manufacture of a multi-layer integrated circuit, a reference target is etched into a test wafer along with circuit features of a reference layer. As successive dependent layers are printed, successive dependent targets overlaying the same reference target are formed in photoresist. As each successive dependent target is printed, the degree to which it is registered with the reference target is used to determine the overlay error. After determination of overlay error for a layer, the layer's dependent target is removed, allowing the reference target to be matched with the dependent target of another layer.