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:
Sep. 15, 2009
Filed:
May. 28, 2004
Amanda Baer, Campbell, CA (US);
Nian-xiang Sun, Sunnyvale, CA (US);
Sue Siyang Zhang, Saratoga, CA (US);
Yi Zheng, San Ramon, CA (US);
Amanda Baer, Campbell, CA (US);
Nian-Xiang Sun, Sunnyvale, CA (US);
Sue Siyang Zhang, Saratoga, CA (US);
Yi Zheng, San Ramon, CA (US);
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
A method of enhancing alignment marks defined in a relatively thin layer on a wafer by etching the alignment marks into an underlying alignment mark transfer layer is described. The target area for the alignment marks is prepared by depositing material for the transfer layer. In alternative embodiments an oversized trench is formed in the target area prior to the deposition of the transfer layer. The alignment marks can fabricated in the layer(s) deposited by the existing process or alternatively, the original layers can be removed and replaced with a layer of material selected to have comparable etching properties (definition layer).