30results about How to "High recording density" patented technology

To provide a method for manufacturing a perpendicular magnetic recording medium which has improved electromagnetic conversion characteristics, and thus making it possible to achieve the much higher recording density.

Disclosed is a method for manufacturing a perpendicular magnetic recording medium to be used for recording information by a perpendicular magnetic recording system, the perpendicular magnetic recording medium including at least a soft magnetic layer, an underlayer, and a magnetic recording layer on a substrate. In the method, the underlayer is formed by sputtering deposition, including a low-gas-pressure deposited layer deposited at a low gas pressure during the deposition, and a high-gas-pressure deposited layer deposited at a high gas pressure during the deposition. The high-gas-pressure deposited layer is formed of a multilayer deposited by decreasing a deposition rate in a stepwise manner.

A write-once optical recording medium has a transparent resin substrate having a concentric groove or a spiral groove and having recessed cells defining recording regions that are arranged in the groove, a recording film comprising an organic dye formed to fill the cells, and a metal reflection film formed on the recording film.

A TAMR (Thermal Assisted Magnetic Recording) write head uses the energy of optical-laser generated plasmons in a plasmon antenna to locally heat a magnetic recording medium and reduce its coercivity and magnetic anisotropy. To enable the TAMR head to operate most effectively, the maximum gradient of the magnetic recording field should be concentrated in the small region being heated. Typically this does not occur because the spot being heated by the antenna is offset from the position at which the magnetic pole concentrates its magnetic field. The present invention incorporates a magnetic core within a plasmon antenna, so the antenna effectively becomes an extension of the magnetic pole and produces a magnetic field whose maximum gradient overlaps the region being heated by edge plasmons being generated in a conducting layer surrounding the antenna's magnetic core.

A magnetic recording medium comprises a non-magnetic substrate, a non-magnetic undercoat layer, a magnetic layer, and a protective film, the layers and film being successively formed on the substrate. The non-magnetic undercoat layer has a multi-layer structure formed of at least two layers and contains a layer A formed of a material selected from a Cr—Ta based alloy, a Cr—Nb-based alloy, a Cr—Ti based alloy, a Cr—Zr-based alloy, and a Cr—Hf-based alloy, and a layer B formed of a material selected from a Co—W based alloy, a Co—W—B-based alloy, a Co—Mo based alloy, a Co—Mo—B based alloy, a Co—W—Mo based alloy, and a Co—W—Mo—B based alloy. The layers A and B are provided in this order from the non-magnetic substrate. A process for producing the medium comprises exposing the surface of the layer B to an oxygen atmosphere.

The present invention provides an aluminium alloy substrate used for a magnetic disc, and a method of manufacturing the same. The aluminium alloy substrate is resistant to impact, has great flatness, and has a plated surface with excellent smoothness. The aluminium alloy substrate is characterized by comprising the following aluminium alloys: below 0.03 by mass of Si, below 0.03 by mass of Fe, over 3.5 and below 4.5 by mass of Mg, below 0.2 by mass of Cr, and at least one selected from over 0.01 and below 0.20 by mass of Cu and over 0.01 and below 0.40 by mass of Zn, the balance being Al and unavoidable impurities, wherein the degree of flatness is less than 5 [mu]m, and the area rate of equiaxed grains on the surface of the substrate is less than 30%.

A head assembly includes a slider having a head element, a load beam, a fulcrum formed at a top end section of the load beam, a slider support plate for supporting the slider to freely turn around the fulcrum, at least one drive element for applying a turning force to the slider support plate in a plane thereof, a first linear link part having at both ends a first top end joint part mechanically connected to the slider support plate, and a first base end joint part mechanically connected to the load beam, and a second linear link part having at both ends a second top end joint part mechanically connected to the slider support plate, and a second base end joint part mechanically connected to the load beam. Both of an extended line of the first linear link part and an extended line of the second linear link part travel toward a position of the fulcrum and intersect with each other.

A magnetic transfer master substrate includes a non-magnetic base having depressed portions formed on a surface thereof corresponding to an information signal array, a ferromagnetic body formed in the depressed portions and having a top portion thereof protruding above the surface of the non-magnetic base, and a non-magnetic protective film covering the surface of the non-magnetic base, except for the depressed portion thereof, and also covering a side portion of the ferromagnetic body. A section through the ferromagnetic body, taken perpendicularly to the substrate, includes a round corner, a curvature of which has a radius of no less than 1 nm and no more than 10 nm. The apex of the top portion of the ferromagnetic body protrudes above the surface of the non-magnetic base by 2 nm or more, and protrudes above the surface of the non-magnetic protective film by a distance less than the radius of the curvature.

A hard bias (HB) structure for longitudinally biasing a free layer in a MR sensor is disclosed that includes a mildly etched seed layer and a hard bias (HB) layer on the etched seed layer. The HB layer may contain one or more HB sub-layers stacked on a lower sub-layer which contacts the etched seed layer. Each HB sub-layer is mildly etched before depositing another HB sub-layer thereon. The etch may be performed in an IBD chamber and creates a higher concentration of nucleation sites on the etched surface thereby promoting a smaller HB average grain size than would be realized with no etch treatments. A smaller HB average grain size is responsible for increasing Hcr in a CoPt HB layer to as high as 2500 to 3000 Oe. Higher Hcr is achieved without changing the seed layer or HB material and without changing the thickness of the aforementioned layers.

An information recording and reproducing apparatus, includes: a recording layer including a first layer including a first compound, the first compound being a conjugated compound including at least two types of cation elements, at least one selected from the cation elements being a transition element having a d orbit incompletely filled by electrons, a shortest distance between adjacent cation elements being not more than 0.32 nm; a voltage application unit that applies a voltage to the recording layer, produces a phase change in the recording layer, and records information; an electrode layer that applies a voltage to the recording layer; and an orientation control layer provided between the recording layer and the electrode layer to control an orientation of the recording layer.

A perpendicular magnetic recording medium is disclosed that includes a substrate; a soft magnetic underlayer formed on the substrate; a seed layer of an amorphous material formed on the soft magnetic underlayer; an oxidation prevention layer formed on the seed layer; an underlayer formed on the oxidation prevention layer, the underlayer including multiple crystal grains formed of Ru or a Ru alloy having an hcp crystal structure, and a first air gap part configured to separate the crystal grains from each other; and a recording layer formed on the underlayer, the recording layer including multiple magnetic particles having a magnetocrystalline easy axis in a direction substantially perpendicular to the surface of the substrate, and one of a second air gap part and a non-magnetic non-solid-solution phase, the one being configured to separate the magnetic particles from each other. The oxidation prevention layer includes a noble metal element other than R.

A reproducing circuit for magnetic disks wherein a MR head bias voltage does not exceed the specified value during any malfunction of the power supply voltage including the cases of power supply ON/OFF, and the central voltage of the MR head is controlled to the ground. The reproducing circuit for magnetic disk apparatus is composed of a MR head, a bias circuit that provides bias voltage specified relative to the MR head, an amplifying circuit for amplifying the output signals of the MR head, a power supply voltage monitor circuit that monitors the changes in the power supply voltage, and a control circuit that is controlled by the power supply voltage monitor circuit. MR bias voltage does not exceed the specified value during any malfunction of the power supply voltage including the cases of power supply ON/OFF, and the central voltage of the MR head is controlled to the ground such that the MR head is protected.

A soft magnetic film is formed of a CoFe alloy having an Fe content in the range of 68 to 80 mass %, thereby having a saturation magnetic flux density of 2.0 T or more. The center lain average roughness of the film surface is 9 nm or less. The soft magnetic film can achieve a corrosive resistant magnetic head with a high recording density.

The present invention discloses an information processing method including the following steps:

• • (1) a first step receiving an encoded information data series as input;
  • (2) a second step selecting a candidate decoded data code series from a first candidate decoded data code series group, decoding the encoded information data series, and generating a first decoded data code series;
  • (3) a third step detecting a position and contents of erroneous decoded data codes in the first decoded data code series that cannot exist in the information data code;
  • (4) a fourth step correcting the erroneous decoded data code and generating a corrected data code;
  • (5) a fifth step selecting a single decoded data code series out of a second candidate decoded data code series group, decoding the encoded information data code series again, and generating a second decoded data code series;
  • (6) The second candidate decode data code series group includes candidate decoded data code series from the first candidate decoded data code series group that fulfills at least one of the following conditions:
• 1. A candidate decoded data code series that does not contain erroneous decoded data codes that were detected at the third step and that could not be corrected at the fourth step.
• 2. A candidate data code series that contains: data codes that were determined at the third step to not contain erroneous decoded data codes; and corrected data codes corrected at the fourth step.

A thermal transfer sheet and yellow ink for use in thermal transfer, with which highly dense clear yellow color can be exhibited with low energy, with which a thermal transfer record excelling in color tone and light fastness can be obtained, and with which a highly dense preferable green tone can be exhibited when mixed with cyan, and to provide a thermal transfer sheet. There is provided a dye composition characterized by containing a dye having an arylidene pyrazolone skeleton and a dye having a bispyrazolone methine skeleton. There is further provided a thermal transfer ink characterized by containing a dye having an arylidene pyrazolone skeleton, a dye having a bispyrazolone methine skeleton and a medium. There is still further provided a thermal transfer sheet comprising a base material and, superimposed thereon, a color material layer containing a dye having an arylidene pyrazolone skeleton and a dye having a bispyrazolone methine skeleton.

Provided is an information storage medium using nanocrystal particles, a method of manufacturing the information storage medium, and an information storage apparatus including the information storage medium. The information storage medium includes a conductive layer, a first insulating layer formed on the conductive layer, a nanocrystal layer that is formed on the first insulating layer and includes conductive nanocrystal particles that can trap charges, and a second insulating layer formed on the nanocrystal layer.

In a data reproducing device using a read channel of a PRML system, during a period of a continuous reproducing operation mode for continuous reproduction processing of adjacent data sectors, a restart RG generator switches a restart read gate signal RRG ON in synchronization with switching ON of a reference read gate signal RG. Therefore, when data is reproduced from a data sector before continuous data sectors, data reproduction processing is started by means of the restart read gate signal RRG equivalent to the reference read gate signal RG. When data is continuously reproduced from a next data sector adjacent to the previous data sector, the restart RG generator switches the restart read gate signal RRG ON ahead of the reference read gate signal RG by a specified period.

A large-capacity, low-cost, longitudinal magnetic recording medium capable of ultra-high-density recording of 70 Gigabits or more per square inch is disclosed. The longitudinal magnetic recording medium of the present invention comprises a first seed layer, a second seed layer, a first underlayer, a second underlayer, and a magnetic layer, which are formed on a nonmagnetic substrate in this order. A material containing at least Al and any one of Ru and Re is used to form the second seed layer, and a material containing at least any one of Co and Ni and one or both of Al and Ti is used to form the first underlayer. It is also possible to use Cr or a Cr alloy containing Cr and at least one element selected from the constituent element group A consisting of Ti, Mo, and W for forming the second seed layer.

The present invention provides a magnetic recording medium capable of obtaining high recording density and also having a hardly charged magnetic layer. The magnetic recording tape 2 (magnetic recording medium) of a preferable embodiment has a magnetic layer 6 containing a SmCo magnetic fine particle 12 and a hydrophilic binder, wherein the SmCo magnetic fine particle 12 has a core 14 made of a SmCo nano particle and a coating layer 16 made of a hydrophilic polymer and coating at least a part of a surface of the core 14.

Provided is a spin valve element capable of performing multi-value recording, which includes a pair of ferromagnetic layers having different coercivities from each other, and sandwiching an insulating layer or a non-magnetic layer. The ferromagnetic layer having the smaller coercivity has a substantially circular in-plane profile, and a plurality of island-shaped non-magnetic portions I_N, I_E, I_W, and I_S are included. In addition, a storage device is manufactured by using such a spin valve element.

The present invention relates to an optical recording medium. The optical recording medium according to one embodiment of the present invention includes a substrate, a reflective layer located on the upper side of the substrate and reflecting an incident laser beam, and an information recording layer located on the reflective layer. The information recording layer includes a first recording layer containing Au and a second recording layer containing at least one element selected from the group consisting of Si, Ge, C, Sn and Zn. Therefore, the optical recording medium of the present invention may provide high recording density and transmittance velocity suitable for BD system by combining the recording layer materials.

In Two-dimensional optical Compensation Exposure method, Beam 1, which has an intensity not less than a sensitivity of a photoresist layer and has a predetermined irradiation timing of exposed patterns, is radiated onto a predetermined area of the photoresist, and Beam 2, which has an intensity less than the sensitivity of the photoresist layer and has an irradiation timing of exposed patterns opposite to the predetermined timing, is radiated onto an area different from the predetermined area. Beam 2, which has the intensity less than the sensitivity of the photoresist layer, is radiated onto both sides P/P (2 T) in a disk radial direction of an area in which a shortest mark P₂₂ is formed. The pit width is uniform irrelevant to the pit length. Further, it is possible to form the pit having a width shorter than a pit length. Therefore, it is possible to realize a high density.

Embodiments of the present invention provide a magnetic disk drive capable of allowing higher data transfer rates and higher recording densities. According to one embodiment, an upper magnetic core and lower magnetic core comprise a multi-layered magnetic film formed by alternately stacking a face-centered cubic (fcc) crystalline magnetic thin layer and a body-centered cubic (bcc) crystalline magnetic thin layer by plating. The plating bath is such that the temperature is about 30±1° C., pH is about 2.0−1.0 to 2.0+0.5, metal ion concentrations are about 5 to 25 (g/l) for Ni2+ and 5 to 15 (g/l) for Fe2+, saccharin sodium concentration is about 1.5±1.0 (g/l), sodium chloride concentration is about 25±5 (g/l), and boric acid concentration is about 25±5 (g/l). Since each layer's crystal structure is different from that of its adjacent lower layer, epitaxial growth is broken within each layer. Thus, since crystal grains are reduced in size, it is possible to lessen the decrease of the permeability μ at higher frequencies.

A method of manufacturing a thin film magnetic head comprising an insulating layer provided between a core and a coil is provided. Also provided is a method for forming an inorganic insulation underlying layer and an organic insulation underlying layer on a lower core layer behind a recording region. The withstand voltage between the lower core layer and the coil layer can be improved because a coil is formed on the organic insulation underlying layer with an inorganic insulation layer disposed on the organic insulation layer.

There is provided an optical element for an objective optical system of an optical information recording/reproducing device. The objective optical system is configured to satisfy conditions: λ<500; NA≧0.7; and f≦1.0, and at least one of surfaces of the optical element includes a diffraction structure defined by an optical path difference function φ(h):

φ(h)=(P₂h²+P₄h⁴+P₆h⁶+P₈h⁸+P₁₀h¹⁰+P₁₂h¹²)mλ

• • where P₂, P₄, P₆ . . . denote coefficients of 2^nd order, 4^th order, 6^th order . . . , respectively, h denotes a height from an optical axis of the optical element, and m denotes a diffraction order at which diffraction efficiency for the laser beam is maximized. The diffraction structure satisfies conditions:

P₂<0  (4);

P₂×P₄<−100  (5); and

−60<P₂/P₄<0  (6).