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. 25, 2018
Filed:
May. 31, 2011
Kazuaki Sakamoto, Singapore, SG;
Takenori Kajiwara, Singapore, SG;
Kazuaki Sakamoto, Singapore, SG;
Takenori Kajiwara, Singapore, SG;
WD MEDIA (SINGAPORE) PTE.LTD., Irvine, CA (US);
Abstract
A method of manufacturing a perpendicular magnetic disk comprises forming, on a base, a film of a first ground layer made of Ru or a Ru alloy at a first pressure, forming, on the first ground layer, a film of a second ground layer made of Ru or a Ru alloy at a second pressure higher than a first pressure, forming, on the second ground layer, a film of a third ground layer having Ru or a Ru alloy as a main component and an oxide as an accessory component at a third pressure higher than the first pressure and lower than the second pressure, and forming, on a layer above the third ground layer, a film of a granular magnetic layer in which a non-magnetic substance having an oxide is segregated around magnetic particles having an CoCrPt alloy grown in a columnar shape to form a grain boundary.