Abstract:
Disclosed is a thermally assisted magnetic recording medium comprising a substrate, a plurality of underlayers formed on the substrate, and a magnetic layer which is formed on the underlayers and predominantly comprised of an alloy having a L10 structure, characterized in that at least one of the underlayers is predominantly comprised of MgO and comprises at least one kind of a metal element having a melting point of at least 2,000° C., such as Nb, Mo, Ru, Ta or W. The thermally assisted magnetic recording medium has magnetic crystal grains having uniform size in the magnetic layer, and has a narrow switching field distribution (SFD), and a magnetic recording storage provided with the thermally assisted magnetic recording medium exhibits a high SN ratio.
Abstract:
A magnetic recording apparatus including a drive unit to drive the magnetic recording medium, a compound-type magnetic head, a means to move the magnetic head relative to the magnetic recording medium, and a means to process recording and retrieving signals generated by the magnetic head. The magnetic recording medium comprises a non-magnetic substrate and a magnetic layer formed thereon with three underlayers interposed inbetween. The magnetic layer is composed of a plurality of layers of Co-based alloy of hexagonal close-packed structure which are antiferromagnetically coupled to one another through a non-magnetic intermediate layer, said three underlayers including an amorphous alloy layer, a Ta layer, and a Cr-based alloy layer of body-centered cubic structure.
Abstract:
A magnetic recording system includes an in-plane magnetic recording medium having a magnetic layer fabricated on a single underlayer or on a plurality of underlayers respectively fabricated on a substrate; a driver unit for driving the in-plane magnetic recording medium in a write direction; a magnetic head having a read unit and a write unit; a unit for moving the magnetic head relative to the in-plane magnetic recording medium; and a read/write signal processing unit for reading an output signal from the magnetic head and writing an input signal to the magnetic recording media, wherein the read unit of the magnetic head is a magnetoresistive head and the single underlayer or at least one of the plurality of underlayers is made of Co-containing amorphous material or fine crystal material, or is made of alloy material, the alloy material having as the main components at least one element selected from a group consisting of Cr, Mo, V and Ta and containing at least one element selected from a group consisting of B, C, P and Bi. The magnetic recording system can be realized which can read and write high density information and have high reliability.
Abstract:
An inplane magnetic recording medium having high S/N and thermal stability and a reliable magnetic storage device having surface recording density of 50 megabit/mm2 or more is described. The magnetic recording medium includes magnetic layers formed on a nonmagnetic substrate with a plurality of ground layers therebetween, at least one of the ground layers formed from an alloy of a body-centered cubic structure containing Cr as a main component and B of from 2 atomic % to 12 atomic %. Main components of the magnetic layers include a lower magnetic layer containing Co and Cr of from 10 atomic % to 16 atomic %, with film thickness of from 1.5 nm to 4.5 nm, and an upper magnetic layer containing Co, coupling anti-ferromagnetically with the lower magnetic layer through nonmagnetic intermediate layers.
Abstract:
A magnetic recording medium capable of attaining high in-plane recording density of 100 Mbits or more per 1 mm2 is provided. Magnetic recording medium is provided in which underlayers, a first magnetic layer, a first intermediate layer, a second magnetic layer, a second intermediate layer, a third magnetic layer, a protection layer and lubrication layer are formed in this order above a substrate. Each of the third magnetic layer and the second magnetic layer comprises a Co-based alloy containing at least Pt, Cr and B. The concentration of Pt contained in the second magnetic layer is not more than that in the third magnetic layer.
Abstract:
It is an object of the present invention to provide a high reliability magnetic storage apparatus capable of performing writing and reading back of high density information. The magnetic storage apparatus is so configured as to have a longitudinal magnetic recording medium including: a magnetic layer formed on a non-magnetic substrate via a plurality of underlayers; the magnetic layer including a lower magnetic layer containing Ru in an amount of not less than 3 at % to not more than 30 at %, and Cr in an amount of not less than 0 at % to not more than 18 at %, and further containing at least one of B or C in an amount of not less than 0 at % to not more than 20 at %, and an upper magnetic layer containing Co as a main component disposed thereon via a non-magnetic intermediate layer.
Abstract:
A magnetic recording medium includes a first underlying film of a NiTa alloy having a nonmagnetic amorphous structure and formed on a nonmagnetic substrate, and a second underlying film made of an alloy containing Cr and Ti, further a first magnetic film of a CoCrPt alloy, a nonmagnetic intermediate film of Ru and a second magnetic film of a CoCrPtB alloy that are serially formed over the first underlying film, wherein oxygen locally exists in an interface between the first underlying film and the second underlying film.
Abstract:
In a magnetic storage apparatus having a magnetic recording medium, a drive unit for driving this medium in a prespecified recording direction, a magnetic head assembly including a recorder section and reproduction section, a way to cause the magnetic head to move relatively with respect to the magnetic record medium, and a record/playback signal processor for performing signal inputting to the magnetic head and for effecting reproduction of an output signal from the magnetic head, the reproduction section of said magnetic head is composed of a magnetic head of the magnetoresistance effect type, while said magnetic record medium is structured including a substrate and a magnetic layer formed thereover with one or several underlayers being sandwiched therebetween, wherein at least one of hte underlayers is a specific layer that is made of amorphous or microcrystalline materials containing therein Ni as the principal or main component thereof and further containing at least one kind of element as selected from the group consisting of Nb and Ta.
Abstract:
A magnetic recording medium having first undercoating layers 40, 40′ formed directly or via substrate face undercoating layers on a substrate 40, second undercoating layers 42, 42′ directly formed on the first undercoating layers 40, 40′, magnetic films 43, 43′ formed on the second undercoating layers 42, 42′, and protective films 44, 44′ formed on the magnetic films 43, 43′. Clusters having a large amount of oxygen are dispersed on the boundary face of the first and second undercoating layers. Preferably, the first undercoating layer is made of an alloy which includes two kinds of elements in which the difference between oxide formation standard free energies &Dgr;G° of the elements at the temperature of 250° C. is large.
Abstract:
A thermal-assist magnetic recording medium is provided which can accomplish a surface recording density of 1 Tbit/inch2. The thermal-assist magnetic recording medium includes: a substrate; a plurality of underlying layers formed on the substrate; a first magnetic layer formed on the underlying layers; a coupling control layer formed on the first magnetic layer and formed of a ferromagnetic alloy; and a second magnetic layer formed on the coupling control layer. Here, Curie temperatures of the first magnetic layer and the second magnetic layer are higher than the Curie temperature of the coupling control layer, an anisotropy magnetic field of the first magnetic layer is greater than the anisotropy magnetic field of the second magnetic layer, and a saturation magnetic field has a minimum value at a temperature of 350° C. or lower.