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:
Oct. 02, 2012
Filed:
Sep. 10, 2010
Jianing Zhou, Fremont, CA (US);
B. Ramamurthy Acharya, Fremont, CA (US);
E. Noel Abarra, Tokyo, JP;
Gunn Choe, San Jose, CA (US);
Jianing Zhou, Fremont, CA (US);
B. Ramamurthy Acharya, Fremont, CA (US);
E. Noel Abarra, Tokyo, JP;
Gunn Choe, San Jose, CA (US);
Seagate Technology LLC, Cupertino, CA (US);
Abstract
A perpendicular recording medium having a perpendicular magnetic recording layer and a magnetically soft underlayer structure disposed beneath the recording layer. The soft underlayer structure includes at least first and second soft magnetic layers having different magnetic permeabilities to create a magnetic permeability gradient in the soft underlayer structure. One or more of the soft magnetic layers can be anti-parallel coupled. The soft underlayer structure of the present invention having a magnetic permeability gradient advantageously leads to reduced adjacent track erasure (ATE) while maintaining good overwrite (OW) properties.