Fuji Electric Co., Ltd.

Fuji Electric Device Technology Co., Ltd.

Takahiro Shimizu

Naoki Takizawa

Hiroyuki Uwazumi

Tadaaki Oikawa

Miyabi Nakamura

Akira Iso

Akihide Hara

Myabi Nakamura

A method and apparatus for manufacturing a magnetic recording medium uses a small-diameter insulating substrate. The apparatus includes a carrier for a special size of 3.5 inches for receiving a plurality of small-diameter insulating substrates. Seed layers are deposited on the substrates, then each substrate is rotated to shift the position of the substrate so that the movable claw contacts the deposited seed layer. A bias voltage is applied via the movable claw for subsequent deposition layers.

Apparatus and method for manufacturing magnetic recording medium

A magnetic recording medium, and method of manufacturing the same, is provided with excellent recording performance by employing a granular magnetic layer having a specified composition. A magnetic recording medium according to the present invention comprises a nonmagnetic underlayer, a granular magnetic layer, a protective film, and a liquid lubrication layer sequentially laminated on a nonmagnetic substrate. The granular magnetic layer consists of ferromagnetic crystal grains containing cobalt and nonmagnetic grain boundary region surrounding the ferromagnetic crystal grains. The ferromagnetic crystal grains contain platinum in the range of 15 at % to 17 at %.

Magnetic recording medium and method for manufacturing the same

A magnetic recording medium exhibiting low noise and having a sufficiently high coercive force includes a magnetic layer having a granular structure including ferromagnetic crystal grains with a hexagonal closed packed structure and a nonmagnetic grain boundary region of mainly an oxide intervening between the crystal grains. An underlayer has a body-centered cubic lattice structure. A nonmagnetic intermediate layer with the hexagonal closest packed structure includes Ru, Os, and/or Re, which are provided between the magnetic layer and the underlayer. A degree of mismatching &#x394;=|d&#x2212;d|/dis at most 10%, for instance, in a range from 2.5% to 7.0%, where dis a spacing of lattice planes of the crystal grains in the magnetic layer and dis a spacing of the lattice planes of the crystal grains in the intermediate layer. A proportion of the crystal grains with a grain size of equal or greater than 8 nm are at most 10% of the crystal grains included in the intermediate layer and a standard deviation of the grain size is at most 1.4 nm. The layers are deposited without preheating the substrate.

Magnetic recording medium exhibiting low noise and high coercive force

A magnetic recording medium has a non-magnetic under-layer, a magnetic layer, a protective film and a liquid lubricant layer sequentially laminated on a non-magnetic substrate. The magnetic layer has a multi-layer structure laminated with two or more magnetic layer components, each of the magnetic layer components having ferromagnetic grains and non-magnetic grain boundaries surrounding the grain. The resulting magnetic recording medium has a granular magnetic layer exhibiting very high Hc accompanying high density of magnetic recording, while decreasing the amount of platinum needed for attaining the high Hc, and reducing media noise accompanying the high recording density.

Magnetic recording medium and method for manufacturing same

A magnetic recording medium for perpendicular magnetic recording system includes a nonmagnetic substrate and layers sequentially laminated on the substrate. The layers include a seed layer comprised of a metal or an alloy with a face centered cubic crystal structure, a nonmagnetic underlayer of a metal or an alloy with a hexagonal closest packed crystal structure, a magnetic layer having a granular structure including ferromagnetic crystalline grains with a hexagonal closest packed structure and nonmagnetic grain boundary region of mainly oxide surrounding the crystalline grains, a protective layer, and a liquid lubricant layer.

Magnetic recording medium

A nonmagnetic foundation layer is made to have a body-centered cubic crystal structure with a preferred crystal orientation plane being the bcc (110) plane. A nonmagnetic intermediate layer, provided between the foundation layer and a granular magnetic layer, has a hexagonal close-packed structure with the hcp (100) plane or the hcp (200) plane being the preferred orientation plane. Furthermore, the crystal lattice misfit amount between the nonmagnetic intermediate layerand the granular magnetic layer is made to be not more than 10% for each of an a-axis and a c-axis. As a result, epitaxial growth of ferromagnetic crystals in the granular magnetic layer, which has an hcp structure, is promoted, and hence the crystallinity of the magnetic layer is increased, and thus it becomes possible to simultaneously realize an increase in coercivity and a reduction in noise. Depositing the layers on an unheated substrate yields reduces manufacturing costs.

Magnetic recording medium and manufacturing method thereof

A method of manufacturing a magnetic recording medium facilitates preventing a film inflation from occurring in an environmental condition range between &#x2212;40&#xb0; C. and 80&#xb0; C. and an 80% relative humidity. The magnetic recording medium includes a plastic substrate and an undercoating layer on the plastic substrate. The undercoating layer is provided with a columnar structure, which prevents water (moisture) between the plastic substrate and the undercoating layer from aggregating and, therefore, the film inflation from occurring.

Method of manufacturing a magnetic recording medium

A magnetic recording medium and a manufacturing method therefore includes a protective film, a nonmagnetic substrate, a nonmagnetic base layer, a nonmagnetic intermediate layer, a magnetic layer, and a liquid lubricant layer. The nonmagnetic base layer has a body-centered cubic structure and a (200) plane including a crystal-orientation parallel with a surface of the protective film. The nonmagnetic intermediate layer has a hexagonal close-packed structure and a (110) plane including a crystal-orientation parallel with the surface of the protective film. The magnetic layer has a granular structure including hexagonal close-packed ferromagnetic crystal grains and oxide-based nonmagnetic grain boundaries surrounding the ferromagnetic crystal grains. The nonmagnetic base layer, the nonmagnetic intermediate layer, the magnetic layer, the protective film, and the liquid lubricant layer are sequentially stacked on the nonmagnetic substrate.

Magnetic recording medium and manufacture method therefor

A magnetic recording medium according to the invention includes a nonmagnetic substrate made of a polymer resin, the nonmagnetic substrate having been treated to improve an adhesion characteristic thereof; an adhesive layer on the nonmagnetic substrate, a nonmagnetic undercoating layer on the an adhesive layer; a magnetic layer above the nonmagnetic undercoating layer; a protection layer above the magnetic layer; and a liquid lubricant layer on the protection layer. A method of manufacturing the magnetic recording medium described above includes the steps of: treating a nonmagnetic substrate to improve an adhesion characteristic thereof; forming an adhesive layer on the nonmagnetic substrate, the adhesion thereof having been improved; forming a nonmagnetic undercoating layer on the adhesive layer; forming a magnetic layer above the nonmagnetic undercoating layer; forming a protection layer above the magnetic layer; and forming a liquid lubricant layer on the protection layer. A magnetic storage device according to the invention mounts thereon the magnetic recording medium described above.

Magnetic recording medium, a method of manufacturing the same, and a magnetic storage device using the magnetic recording medium

A manufacturing method achieves excellent magnetic recording characteristics by sequentially sputtering a non-magnetic under-layer, a non-magnetic intermediate layer, and a magnetic layer on a non-magnetic substrate in an atmosphere of H O partial pressure of 2&times;10 Torr or lower. This process allows beneficial deposition of the magnetic layer and reduces raw materials costs. The magnetic layer includes ferromagnetic grains and non-magnetic grain boundaries. The intermediate layer has a hexagonal close-packed crystal structure. The manufacturing method allows manufacture of a high quality magnetic recording medium without a heating step thereby allowing use of lower cost materials, reduces manufacturing time, and increases savings.

Method for manufacturing a magnetic recording medium

In a magnetic recording medium, a plurality of non-magnetic metallic intermediate layers is laminated between an under-layer and a magnetic layer. One of the intermediate layers is composed of at least an element selected from the group consisting of Ru, Re and Os and contains oxygen, and another is composed of a CoCr alloy containing at least an element selected from the group consisting of Nb, Mo, Ru, Rh, Pd, Ta, W, Re Os, Ir and Pt. The resulting magnetic recording medium provides reduced costs and improved recording characteristics.

Magnetic recording medium, method for manufacturing a magnetic recording medium and magnetic recording device

A magnetic recording medium has at least a non-magnetic under-layer, a magnetic layer, a protective layer and a liquid lubricant layer sequentially laminated on a non-magnetic substrate. The magnetic layer includes ferromagnetic grains and non-magnetic grain boundaries formed of metallic oxide or carbide surrounding the ferromagnetic grains. A non-magnetic intermediate layer, having grains of non-magnetic substance and non-magnetic grain boundaries, formed of metallic oxide or carbide, surrounding the grains of non-magnetic substance, is provided between the non-magnetic under-layer and the magnetic layer. The resulting magnetic recording medium exhibits a high coercive force, Hc, and low noise. Furthermore, the resulting magnetic recording medium prevents the deterioration of the media characteristics in an initial growth region in the granular magnetic layer.

Recording medium and method for manufacturing the same

A magnetic recording medium achieves excellent noise reduction by controlling the crystal orientation of a magnetic layer without thermal processing. The magnetic recording medium includes multiple layers laminated to a substrate. These layers include at least the magnetic layer and a non-magnetic under layer. The magnetic layer has a granular structure consisting of ferromagnetic grains with a hexagonal close-packed structure and non-magnetic grain boundaries composed mainly oxide or a nitride. The non-magnetic under-layer is a material having a body centered cubic crystal structure with a preferential orientation along a (200) plane parallel to a film surface of the under-layer.

Growing community of inventors

Nagano, Japan

Takahiro Shimizu