Other

Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Toshiba Corporation

Hiro Mochizuki

Hiroshi Sakai

Akira Sakawaki

Kenji Shimizu

Takashi Hikosaka

Hui Yang

Soichi Oikawa

Masakazu Kobayashi

Futoshi Nakamura

Masato Kokubu

A magnetic recording medium having excellent magnetic read/write characteristics and thermal stability characteristics, and a method of manufacturing therefor, and a magnetic read/write apparatus are provided. This magnetic recording medium comprises an orientation control filmthat controls the orientation of a film provided directly thereabove, a perpendicular magnetic filmof which the axis of easy magnetization is generally oriented perpendicular to a substrate, and a protective filmthat are provided on a non-magnetic substratewherein the orientation control filmis made of a non-magnetic material which contains 33 to 80 at % of Ni and one or more kinds of elements selected from Sc, Y, Ti, Zr, Hf, Nb and Ta.

Magnetic recording medium, including an HCP structured Ni-alloy control film method of manufacture therefor, and magnetic read/write apparatus

A magnetic recording medium having a non-magnetic substrate; an orientation-regulating layer for regulating the crystal orientation of a layer provided directly thereon; a perpendicular magnetic layer in which easy-magnetization axes are oriented generally perpendicular to the substrate; and a protective layer is disclosed. The perpendicular magnetic layer is formed from a material containing Co as a primary component and at least Cr, Pt, and Nd. A process to produce the magnetic recording medium and a magnetic recording and reproducing apparatus are also disclosed.

Magnetic recording medium, production process thereof, and magnetic recording and reproducing apparatus

A magnetic recording medium that is capable of recording and reading back information at a higher density by improving the read/write characteristics and thermal stability, a method of manufacture therefor, and a magnetic read/write apparatus are provided. This magnetic recording medium, comprises an orientation control film that controls the orientation of a film provided directly thereabove, a perpendicular magnetic film, of which the axis of easy magnetization is generally oriented perpendicular to a non-magnetic substrate, and a protective film, that are provided on the non-magnetic substrate, wherein the perpendicular magnetic film is made of a material which contains Co, Cr, Pt and Cu, the Cr content being 16 at % to 24 at % and the Cu content being 0.1 at % to 4 at %, and a coercive force (Hc) of the perpendicular magnetic film being at least 3000 (Oe), negative nucleation field (&minus;Hn) being 0 (Oe) to 2500 (Oe), and a ratio of residual magnetization (Mr) to saturation magnetization (Ms) being at least 0.85.

Magnetic recording medium, method of manufacture therefor, and magnetic read/write apparatus

The present invention provides a magnetic recording medium having excellent magnetic read/write characteristics and thermal stability, a method of manufacturing therefor, and a magnetic read/write apparatus. The magnetic recording medium comprises a soft magnetic undercoat film, an orientation control film, a perpendicular magnetization film, and a protective film, that are formed on a non-magnetic substrate, wherein the orientation control film has an hcp structure and, at the same time, &Dgr;&thgr;50 of the ( ) orientation plane is set within a range from 3 to 10 degrees and a difference (&Dgr;&thgr;50 (mag)&minus;&Dgr;&thgr;50 (ori)) between &Dgr;&thgr;50 (ori) of the orientation control film and &Dgr;&thgr;50 (mag) of the perpendicular magnetization film is set within a range from 1 to 8 degrees.

Magnetic recording medium, method of manufacturing therefor, and magnetic read/write apparatus

Growing community of inventors

Ichihara, Japan

Hiro Mochizuki