Fujitsu Corporation

Takashi Gouke

Akira Kikuchi

Chiaki Okuyama

Atsushi Endo

Reiko Murao

A perpendicular magnetic recording medium is provided with a substrate, a soft magnetic back layer provided on a surface of the substrate, an orientation controlling underlayer provided on the soft magnetic back layer, and a recording layer provided above the orientation controlling underlayer and having axes of easy magnetization approximately perpendicular to the surface of the substrate. The recording layer is made of a ferromagnetic material having an hcp crystal structure. The orientation controlling underlayer is made of a nonmagnetic material having an fcc crystal structure and having NiCr or NiCu as a main component.

Perpendicular magnetic recording medium and magnetic storage apparatus

A magnetic recording medium is disclosed that is able to increase a coercive force Hc of a recording layer and improve a signal-to-noise ratio of the recording layer without degradation of a thermal fluctuation resistance of the recording layer, and enables high density recording. The magnetic recording medium includes a substrate, a seed layer formed from a crystalline material, a grain diameter control layer, an underlying layer, and a recording layer. The grain diameter control layer is formed from an Ag film or a W film, to be a dispersed film or a continuous film on the seed layer. The grain diameter control layer acts as growing nuclei of the underlying layer formed thereon, and controls crystal grain diameters of the underlying layer. Especially, when the grain diameter control layer is deposited to be a dispersed layer, the underlying layer grows on the seed layer and the grain diameter control layer, and due to influence of the surface of the seed layer, the crystalline property of the underlying layer is improved.

Magnetic recording medium and magnetic storage device

A magnetic recording medium includes a substrate, an AlFe-based alloy layer provided above the substrate, an underlayer provided on the AlFe-based alloy layer, and a recording layer provided on the underlayer and magnetized in a predetermined recording direction when being recorded with information. The substrate has a textured surface having grooves formed approximately along the recording direction.

Magnetic recording medium and magnetic storage apparatus

A magnetic recording medium which is thermally stable and produces low media noise. By providing a plurality of intermediate layers made of a CoCr alloy of which saturation magnetic flux densities are controlled within a predetermined range, the magnetic recording medium simultaneously realizes both a high S/Nm and thermal stability.

Thermally stable low noise magnetic recording media

A polycrystalline structure film is formed on the surface of a substrate in a magnetic recording medium. The second magnetic layer has a saturation magnetic flux density Bs larger than that of the first magnetic layer in the polycrystalline structure film, so that the magnetic layer for recordation ensures a larger residual magnetization Br, as compared with the case where the first magnetic layer solely forms a magnetic layer for recordation. A sufficient magnitude of product tBr of thickness t and residual magnetization Br can be obtained even if the thickness of the overall magnetic layer for recordation is reduced. A sufficient magnitude of magnetic outputs can be ensured. A reduced thickness of the magnetic layer serves to minimize the magnetic crystal grains in the first and second magnetic layers. A higher resolution of recordation and reproduction can be obtained.

Growing community of inventors

Higashine, Japan

Takashi Gouke