Hgst Netherlands, B.v.

Hitachi Global Storage Technologies Netherlands B.v.

Hiroshi Kanai

Toshinori Ono

Hiroshi Inaba

Hiroyuki Suzuki

Tatsuya Hinoue

Hiroyuki Matsumoto

Mitsuhiro Shoda

Nobuto Yasui

Tatsuysa Hinoue

Embodiments of the present invention provide a manufacturing method that can form a track guide separation area of a magnetic disk substrate constituting a patterned medium represented by a discrete track medium or bit patterned medium suitable for high recording density, uniformly on the whole surface of the magnetic disk substrate, and accurately according to the mask. According to one embodiment, a soft magnetic film, an under coating film, and a magnetic film are formed on a substrate. A mask having an arbitrary pattern shape provided for forming the track guide separation area in the magnetic film is formed on the magnetic film, and the track guide separation area is formed by irradiating ions and electrons onto the surface of the magnetic film and applying an intermittent voltage to the substrate, thereby non-magnetizing the area irradiated.

Method for manufacturing magnetic recording medium

Embodiments of the present invention produce discrete track media and bit patterned media having both excellent read/write performance and reliability. According to one embodiment, the medium comprises a magnetic layers formed by at least two ferromagnetic alloy layers with different compositions on a substrate. The ferromagnetic alloy layer located closest to the medium surface has more concentrated parts and less concentrated parts of nonmagnetic element in the in-plane direction. The more concentrated parts of the nonmagnetic element contain more nonmagnetic elements than the other parts except for an intermediate layer in the magnetic recording layer. The more concentrated parts and the less concentrated parts of the nonmagnetic element in the ferromagnetic alloy layer located closest to the medium surface are formed substantially concentric. The more concentrated parts of the nonmagnetic element is formed by being doped with ions of nonmagnetic element.

Magnetic recording medium utilizing a recording layer having more and less concentrated parts of a nonmagnetic element in an in-plane direction and manufacturing method thereof

Embodiments of the present invention provide recording area separated magnetic recording media (DTMs, BPMs) allowing magnetic heads to fly lower. According to one embodiment, the recording area separated magnetic recording media are configured so that magnetic recording layers have parts with the relatively higher element ratio of a ferromagnetic material, and parts with the lower element ratio of the ferromagnetic material, occurring periodically in the in-plane direction, and the average height from the substrate surface of the parts with the relatively higher element ratio of a ferromagnetic material is higher than the average height from the substrate surface of the parts with the lower element ratio of the ferromagnetic material. In producing recording area separated magnetic recording media with the element ratio of a ferromagnetic material relatively lowered by ion implantation, preliminarily etching the part to be ion implanted makes the height after ion implantation relatively lower than the non-implanted part.

Magnetic recording medium having ion-implanted parts

Embodiments of the present invention help to produce discrete track media and bit patterned media having both excellent recording and reproducing performance and reliability. According to one embodiment, a manufacturing method forms a nonmagnetic layer mainly composed of the same element as a nonmagnetic element contained in magnetic recording layers and on the magnetic recording layers and a mask layer having apertures for forming more concentrated parts of the nonmagnetic element in the magnetic recording layers on the nonmagnetic layer. The method implants ions of the nonmagnetic element through the nonmagnetic layer masked by the mask layer to form the more concentrated parts of the nonmagnetic element in the magnetic recording layer.

Magnetic recording medium utilizing a recording layer having more and less concentrated parts of a nonmagnetic element in an in-plane direction and a nonmagnetic layer

Embodiments of the present invention help to improve corrosion resistance and durability by providing a functional diamond like carbon (DLC) protective layer for a perpendicular magnetic recording medium using a granular magnetic layer. According to one embodiment, when a DLC protective layer that protects a granular magnetic layer of a perpendicular magnetic recording medium is formed using a CVD method, the thickness of a first layer on the granular magnetic layer is set to 7.5 to 25% of the total thickness of the protective layer and a hydrogen content of the first layer is set to 33 to 38%, the thickness of a second layer is set to 50 to 85% of the total thickness of the protective layer and a nitrogen content of the second layer is set to 3 to 7%, and the thickness of a third layer located at the outermost side of the protective layer is set to 7.5 to 25% of the total thickness of the protective layer and a hydrogen content of the third layer is set to 25% or less.

Growing community of inventors

Kanagawa-ken, Japan

Hiroshi Kanai