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:
Apr. 21, 2015
Filed:
Nov. 10, 2011
Takeshi Iwasaki, Inagi, JP;
Kaori Kimura, Yokohama, JP;
Hiroyuki Hyodo, Hino, JP;
Masatoshi Sakurai, Tokyo, JP;
Takeshi Iwasaki, Inagi, JP;
Kaori Kimura, Yokohama, JP;
Hiroyuki Hyodo, Hino, JP;
Masatoshi Sakurai, Tokyo, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Abstract
According to one embodiment, a magnetic recording medium is formed by performing gas ion irradiation by using a magnetism deactivating gas on a stack including a perpendicular magnetic recording layer, an Ru nonmagnetic underlayer containing a magnetism deactivating element selected from chromium, titanium, and silicon, and a nonmagnetic substrate. Before gas ion irradiation, the perpendicular magnetic recording layer contains platinum and at least one of iron and cobalt. Gas ion irradiation is performed using nitrogen gas alone or a gas mixture of nitrogen gas and at least one gas selected from the group consisting of helium, hydrogen, and BH.