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. 02, 2014
Filed:
Apr. 28, 2014
Hgst Netherlands B.v., Amsterdam, NL;
Bruce Alvin Gurney, San Jose, CA (US);
En Yang, Los Altos, CA (US);
HGST Netherlands B.V., Amsterdam, NL;
Abstract
A perpendicular magnetic recording disk has servo regions that have a patterned underlayer with seed layer pillars formed on the underlayer pillars above the underlayer trenches. The underlayer is made of an oxidizable material. Magnetic recording material is located on the seed layer pillars and on an oxide layer in the underlayer trenches. The magnetic material in the trenches exhibits a magnetic field substantially less than the magnetic field exhibited by the magnetic material on the seed layer pillars, which has perpendicular magnetic anisotropy. The reduced magnetic field from the trenches results from structural differences between the magnetic material on the seed layer pillars and in the trenches, such as smaller grain size of the magnetic material on the seed layer pillars and a wider distribution of crystallographic axes of the magnetic material in the trenches. The seed layer may be made of a material substantially non-reactive with oxygen.