Abstract: A magnetic recording medium includes a non-magnetic substrate, an inorganic compound layer that is formed on the substrate and which contains a crystalline first oxide and a second oxide, and a magnetic layer that is formed on the inorganic compound layer. The crystalline first oxide comprises at least one oxide selected from cobalt oxide, chromium oxide, iron oxide and nickel oxide. The second oxide comprises at least one oxide selected from silicon oxide, aluminum oxide, titanium oxide, tantalum oxide and zinc oxide. The second oxide is present at a grain boundary of crystal grains of said first oxide. According to the present invention, magnetic recording media low in noise and diminished in thermal fluctuation and thermal decay can be obtained by making fine the crystal grains of a magnetic layer and controlling the dispersion of the grain size. Thus, magnetic recording apparatuses can be realized which can perform an ultrahigh density magnetic recording of higher than 20 Gb/in2.

Abstract: Magnetic recording medium includes at least two layers having different magnetic anisotropy constants formed on a substrate and the perpendicular magnetic anisotropy of the second magnetic film of those magnetic films, far from the substrate surface, made equal to or larger than that of the first magnetic film near to the substrate surface, thus improving the magnetic isolation of the first magnetic film near to the substrate surface.

Abstract: It is an object of the present invention to provide a magnetic recording medium which has a high level of magnetic anisotropy energy, retains stably the state of recording magnetization within the operating temperature range and is suitable for high-density recording with a low noise level, and a magnetic storage device for the magnetic recording medium.

Abstract: A magnetic recording medium includes a substrate, an underlayer provided on the substrate, a Co alloy magnetic film formed through the underlayer, and a protective film for protecting the magnetic film, wherein the underlayer has a two-layer structure of an lower underlayer contacted with the substrate and an upper underlayer contacted with the Co alloy magnetic film, the upper underlayer is a Co—Crx—My alloy film having a hexagonal close-packed structure, where 25 atomic %≦x+y≦50 atomic %, 0.5 atomic % y, nonmagnetic element M is one selected from the group of elements B, Si, Ge, C, Al, P, Ti, V, Nb, Zr, Hf, Mn, Rh, Os, Ir, Re, Pd, Pt, Mo, Ta, W, Ag and Au. Thereby the medium can be increased in its coercive force and can be improved in its thermal stability characteristics.

Abstract: An in-plane magnetic recording medium comprises, on a substrate, a first underlying base layer of NiAl, a second underlying base layer of CrMo, a ferromagnetic atom-rich layer of CoPt, a magnetic coupling layer of Ru, a recording layer of CoCrPtB, and a protective layer of carbon. The magnetic coupling layer brings about exchange coupling force between the recording layer and the ferromagnetic atom-rich layer. The ferromagnetic atom concentration is high in the ferromagnetic atom-rich layer as compared with the recording layer. Therefore, the exchange coupling force, which is exerted between the ferromagnetic atom-rich layer and the recording layer, is remarkably improved. Accordingly, it is possible to provide a magnetic recording apparatus which is excellent in recording stability over a long period of time in which the thermal stability of the magnetic recording medium is excellent.

Abstract: Magnetic recording medium includes at least two layers having different magnetic anisotropy constants formed on a substrate and the perpendicular magnetic anisotropy of the second magnetic film of those magnetic films, far from the substrate surface, made equal to or larger than that of the first magnetic film near to the substrate surface, thus improving the magnetic isolation

Abstract: A magnetic recording medium includes a substrate, an underlayer provided on the substrate, a Co alloy magnetic film formed through the underlayer, and a protective film for protecting the magnetic film, wherein the underlayer has a two-layer structure of an lower underlayer contacted with the substrate and an upper underlayer contacted with the Co alloy magnetic film, the upper underlayer is a Co—Crx—My alloy film having a hexagonal close-packed structure, where 25 atomic %≦x+y≦50 atomic %, 0.5 atomic %≦y, nonmagnetic element M is one selected from the group of elements B, Si, Ge, C, Al, P, Ti, V, Nb, Zr, Hf, Mn, Rh, Os, Ir, Re, Pd, Pt, Mo, Ta, W, Ag and Au. Thereby the medium can be increased in its coercive force and can be improved in its thermal stability characteristics.

Abstract: A magnetic sensor is constructed to be capable of detecting the change of tunnel current due to co-tunneling effect at a high S/N ratio by using a tunneling magneto-resistive element having a first magnetic layer of a soft magnetic material formed on a flat substrate, first and second tunnel barrier layers formed on the first magnetic layer, magnetic particles of a ferromagnetic material provided between the first and second tunnel barrier layers, and a second magnetic layer of a soft magnetic material formed on the second tunnel barrier layer so as to create tunneling junctions.

Abstract: It is an object of the present invention to provide a magnetic recording medium which has a high level of magnetic anisotropy energy, retains stably the state of recording magnetization within the operating temperature range and is suitable for high-density recording with a low noise level, and a magnetic storage device for the magnetic recording medium. For attaining the above object, the magnetic recording film of the magnetic recording medium is characterized in that its magnetic anisotropy energy constant Ku at an absolute temperature of 300 K is greater than 3.6×106 erg/cc and the average particle diameter is larger than 5 nm and smaller than 12 nm.

Abstract: A magnetic sensor is constructed to be capable of detecting the change of tunnel current due to co-tunneling effect at a high S/N ratio by using a tunneling magneto-resistive element having a first magnetic layer of a soft magnetic material formed on a flat substrate, first and second tunnel barrier layers formed on the first magnetic layer, magnetic particles of a ferromagnetic material provided between the first and second tunnel barrier layers, and a second magnetic layer of a soft magnetic material formed on the second tunnel barrier layer so as to create tunneling junctions.

Abstract: A ferromagnetic thin film is used to provide a magnetic recording medium whose noise is low and whose S/N is high. The ferromagnetic thin film as the magnetic film of the magnetic recording medium is such that the fluctuation field of magnetic viscosity at 25° C. at the field strength equal to remanence coercivity or coercivity is not less than 15 oersteds and the coercivity is not less than 2000 oersteds.

Abstract: A thin film magnetic recording medium including a magnetic layer having a fluctuation field defined as S/Xirr, where S is magnetic viscosity and Xirr is irreversible susceptibility Xirr. The fluctuation field of the magnetic layer is not less than 15 oersteds.

Abstract: Magnetic recording medium includes at least two layers having different magnetic anisotropy constants formed on a substrate and the perpendicular magnetic anisotropy of the second magnetic film of those magnetic films, far from the substrate surface, made equal to or larger than that of the first magnetic film near to the substrate surface, thus improving the magnetic isolation of the first magnetic film near to the substrate surface.

Abstract: A magnetic recording medium capable of reducing noise and an error rate of the medium comprises a nonmagnetic substrate; a magnetic layer formed on the surface of the nonmagnetic substrate directly or through a nonmagnetic underlayer; and a protective layer formed on the magnetic layer. The magnetic recording medium satisfies the following relationships: −0.5≦{Hc(1)−Hc(p)}/Hc(1)≦0.3 Hc(1)≧2 kOe 20 G×&mgr;m≦Br(1)×t≦100 G×&mgr;m where Hc(1) is a corecivity of the magnetic layer measured in the longitudinal direction; Hc(p) is a coercivity of the magnetic layer measured in the perpendicular direction; Br(1) is a remanent magnetization of the magnetic layer measured in the longitudinal direction; and “t” is a layer thickness of the magnetic layer.

Abstract: A magnetic sensor is constructed to be capable of detecting the change of tunnel current due to co-tunneling effect at a high S/N ratio by using a tunneling magnetoresistive element having a first magnetic layer of a soft magnetic material formed on a flat substrate, first and second tunnel barrier layers formed on the first magnetic layer, magnetic particles of a ferromagnetic material provided between the first and second tunnel barrier layers, and a second magnetic layer of a soft magnetic material formed on the second tunnel barrier layer so as to create tunneling junctions.

Abstract: The present invention relates to a perpendicular magnetic recording medium and a magnetic storage apparatus which are improved to be suitable for high-density magnetic recording. An object thereof is to provide the perpendicular magnetic recording medium and the magnetic storage apparatus which have a low noise property for realizing a recording density of 10 Gb/in.2 or more and a high stability against thermal fluctuation. The perpendicular magnetic recording medium comprising a perpendicular magnetic film formed through an underlayer on a nonmagnetic substrate, wherein the underlayer comprises a material having a hexagonal close packed structure or an amorphous structure, and has a first underlayer nearer to the substrate, and a second underlayer having a hexagonal close packed structure formed on the first underlayer and a preferred growth orientation of [0001] and comprising a material capable of hetero-epitaxy growth onto the perpendicular magnetic film.

Abstract: A magnetic recording system high in S/N and low in bit error rate, capable of carrying out writing and reading of high recording density of at least 1 gigabit per 1 square inch and high in reliability can be realized by making the magnetic layer of the magnetic recording medium from a mixture comprising at least one non-magnetic compound selected from the group consisting of oxides and nitrides and a magnetic material comprising Co and Pt as main components and specifying the molar ratio of Pt to Co in the magnetic layer, and employing a magnetoresistive read back magnetic recording head.

Abstract: A magnetic recording system high in S/N and low in bit error rate, capable of carrying out writing and reading of high recording density of at least 1 gigabit per 1 square inch and high in reliability can be realized by making the magnetic layer of the magnetic recording medium from a mixture comprising at least one non-magnetic compound selected from the group consisting of oxides and nitrides and a magnetic material comprising Co and Pt as main components and specifying the molar ratio of Pt to Co in the magnetic layer, and employing a magnetoresistive read back magnetic recording head.

Abstract: A magnetic recording media with a magnetic film made from at least two layers stacked via a non-magnetic intermediate layer, wherein the magnetic film is formed on a structure control underlayer situated on a non-magnetic substrate. A magnetic recording system is also disclosed which includes this magnetic recording media and a magnetic recording head for recording on and reading back from the magnetic recording media. The system further includes a disk drive system, which generates relative motion between the magnetic recording media and the magnetic recording head, and an actuator which determines an appropriate location, on the magnetic recording media, over which the head should be located.

Abstract: A magnetic recording system includes an intermediate layer arranged between adjacent ones of a plurality of magnetic layers constituting a magnetic recording medium, the magnetic recording medium driven by a drive section in the recording direction, and a magnetic head including a write section and a read-back section set in relative motion with respect to the magnetic recording medium. Signals are applied to the magnetic head and the output signals from the magnetic head are read back by a read/write signal processing device. The read-back section of the magnetic head includes a magnetoresistive magnetic head. The magnetic layers of the magnetic recording medium include crystal grains having different crystal orientations and existing in overlapped positions in the direction perpendicular to the medium surface. High-density information read/write operation thus is made possible with an improved reliability.