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AssigneeWD Media (Singapore) Pte. Ltd.
InventorsYoshiaki Sonobe, Teiichiro Umezawa, Chikara Takasu
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A magnetic disk 10 for use in perpendicular magnetic recording has at least a magnetic recording layer on a substrate 1. The magnetic recording layer is composed of a ferromagnetic layer 5 of a granular structure containing silicon (Si) or an oxide of silicon (Si) between crystal grains containing cobalt (Co), a stacked layer 7 having a first layer containing cobalt (Co) or a Co alloy and a second layer containing palladium (Pd) or platinum (Pt), and a spacer layer 6 interposed between the ferromagnetic layer 5 and the stacked layer 7. After forming the ferromagnetic layer 5 on the substrate 1 by sputtering in an argon gas atmosphere, the stacked layer 7 is formed by sputtering in the argon gas atmosphere at a gas pressure lower than that used when forming the ferromagnetic layer 5.
A perpendicular magnetic recording disk for use in perpendicular magnetic recording, said perpendicular magnetic recording disk characterized by comprising a substrate, a soft magnetic layer of a material selected from a group consisting of an Fe-based material and a Co-based material on said substrate, and a magnetic recording layer on said soft magnetic layer, wherein said magnetic recording layer comprises a ferromagnetic layer on said soft magnetic layer, having a granular structure, and comprising crystal grains mainly made of cobalt (Co) and grain boundary portions mainly made of SiO2, a spacer layer selected from a group consisting of a Pd layer and a Pt layer on said ferromagnetic layer, and a layer, on said spacer layer, having no granular structure and comprising alternating films of Co or an alloy thereof and Pd or alternating films of Co or an alloy thereof and Pt, the content of the SiO2 in said ferromagnetic layer being 8 at% to 15 at%, said perpendicular magnetic recording disk comprising, on said substrate, said soft magnetic layer, said ferromagnetic layer having the granular structure, said spacer layer, and said layer having no granular structure in this order;
A method of manufacturing a perpendicular magnetic recording disk for use in perpendicular magnetic recording and having at least a soft magnetic layer of a material selected from a group consisting of an Fe-based material and a Co-based material on a substrate and a magnetic recording layer on said soft magnetic layer, said method characterized by, in a step of forming said magnetic recording layer comprising, on said soft magnetic layer, a ferromagnetic layer of a granular structure comprising SiO2 between crystal grains comprising cobalt (Co), the content of the SiO2 in said ferromagnetic layer being 8 at% to 15 at%, a spacer layer selected from a group consisting of a Pd layer and a Pt layer on said ferromagnetic layer, and a layer, on said spacer layer, having no granular structure and comprising alternating films of Co or an alloy thereof and Pd or alternating films of Co or an alloy thereof and Pt, forming said ferromagnetic layer on said soft magnetic layer by sputtering in an argon gas atmosphere and then forming said layer having no granular structure by sputtering in an argon gas atmosphere at a gas pressure lower than a gas pressure used when forming said ferromagnetic layer,
A method of manufacturing a perpendicular magnetic recording disk for use in perpendicular magnetic recording and having at least a soft magnetic layer of a material selected from a group consisting of an Fe-based material and a Co-based material on a substrate, an underlayer including Ru on said soft magnetic layer, and a magnetic recording layer on said underlayer, said method characterized by,
Dependencies are inferred from the claim text.