Abstract: Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc and a process for production thereof. The sputtering target is a sputtering target comprising metallic Co, metallic Pt, and an oxide, wherein the sputtering target does not contain metallic Cr, and the oxide is WO3 and wherein the sputtering target comprises 25 to 50 at % of metallic Co relative to a total of metallic Co and metallic Pt.

Abstract: Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc and a process for production thereof. The sputtering target is a sputtering target comprising metallic Co, metallic Pt, and an oxide, wherein the sputtering target does not contain metallic Cr, and the oxide is WO3 and wherein the sputtering target comprises 25 to 50 at % of metallic Co relative to a total of metallic Co and metallic Pt.

Abstract: The present invention relates to Fe16N2 particles in the form of a single phase which are obtained by subjecting iron oxide or iron oxyhydroxide whose surface may be coated with at least alumina or silica, if required, as a starting material, to reducing treatment and nitridation treatment, a process for producing the Fe16N2 particles in the form of a single phase for a heat treatment time of not more than 36 hr, and further relates to an anisotropic magnet or a bonded magnet which is obtained by magnetically orienting the Fe16N2 particles in the form of a single phase. The Fe16N2 particles according to the present invention can be produced in an industrial scale and have a large BHmax value.

Abstract: Ferromagnetic particles including an Fe16N2 compound phase in an amount of not less than 80% as measured by Mössbauer spectrum and each having an outer shell in which FeO is present in the form of a film having a thickness of not more than 5 nm. Ferromagnetic particles may be made by subjecting iron oxide or iron oxyhydroxide having an average major axis diameter of 40 to 5000 nm and an aspect ratio (major axis diameter/minor axis diameter) of 1 to 200 as a starting material to dispersing treatment to prepare aggregated particles; subjecting the iron compound particles passed through a mesh to hydrogen reducing treatment at a temperature of 160 to 420° C.; and then subjecting the resulting particles to nitridation treatment at a temperature of 130 to 170° C.

Abstract: There are provided a method for manufacturing a magnetic recording medium which is excellent in terms of both the recording and reproduction characteristics and the thermal fluctuation characteristics without reducing the density and hardness of the perpendicular magnetic layer; a magnetic recording medium; and a magnetic recording and reproducing apparatus with which an excellent recording density is achieved, wherein, in the method for manufacturing the magnetic recording medium, at least a portion of the perpendicular magnetic layer 4 is formed as a magnetic layer having a granular structure that contains Co as a major component and also contains an oxide of at least one nonmagnetic metal selected from the group consisting of Cr, Si, Ta, Al, Ti, W and Mg; a target for forming the perpendicular magnetic layer 4 by the sputtering process is prepared so as to include an oxide of Co and a compound of Co and at least one nonmagnetic metal selected from the group consisting of Cr, Si, Ta, Al, Ti, W and Mg, an

Abstract: The present invention provides ferromagnetic iron nitride particles, in particular, in the form of fine particles, and a process for producing the ferromagnetic iron nitride particles. The present invention relates to a process for producing ferromagnetic iron nitride particles, comprising the steps of mixing metallic iron obtained by mixing at least one compound selected from the group consisting of a metal hydride, a metal halide and a metal borohydride with an iron compound, and then subjecting the obtained mixture to heat treatment, with a nitrogen-containing compound; and then subjecting the resulting mixture to heat treatment, in which a reduction step and a nitridation step of the iron compound are conducted in the same step, and the at least one compound selected from the group consisting of a metal hydride, a metal halide and a metal borohydride is used as a reducing agent in the reduction step, whereas the nitrogen-containing compound is used as a nitrogen source in the nitridation step.

Abstract: According to one embodiment, there is provided a thin magnetic film having a negative anisotropy of ?6×106 erg/cm3 or less and including, on at least a nonmagnetic substrate, at least one seed layer made of a metal or metal compound, a ruthenium underlayer for controlling the orientation of an immediately overlying layer, and a magnetic layer having negative anisotropy in the normal line direction perpendicular to a surface of the magnetic layer and mainly containing Co and Ir, wherein the additive element concentration of Ir in the magnetic layer is 10 (inclusive) to 45 (inclusive) at %.

Abstract: According to one embodiment, there is provided a thin magnetic film having a negative anisotropy of ?6×106 erg/cm3 or less and including, on at least a nonmagnetic substrate, at least one seed layer made of a metal or metal compound, a ruthenium underlayer for controlling the orientation of an immediately overlying layer, and a magnetic layer having negative anisotropy in the normal line direction perpendicular to a surface of the magnetic layer and mainly containing Co and Ir, wherein the additive element concentration of Ir in the magnetic layer is 10 (inclusive) to 45 (inclusive) at %.

Abstract: A magnetic recording medium is disclosed in which, on a non-magnetic substrate 1, at least an orientation control layer that controls orientation of a layer immediately above and a vertical magnetic layer in which an easy axis of magnetization is mainly vertically oriented with respect to the non-magnetic substrate are laminated. The orientation control layer includes an Ru-containing layer containing Ru or Ru alloy, and a diffusion prevention layer provided on the Ru-containing layer on the side of the vertical magnetic layer, is made of a material having a melting point of 1500° C. or higher and 4215° C. or lower and formed by a covalent bond or an ionic bond, and prevents thermal diffusion of Ru atoms of the Ru-containing layer.

Abstract: The present invention relates to ferromagnetic particles capable of exhibiting a high purity and excellent magnetic properties from the industrial viewpoints and a process for producing the ferromagnetic particles, and also provides an anisotropic magnet, a bonded magnet and a compacted magnet which are obtained by using the ferromagnetic particles. The ferromagnetic particles comprising an Fe16N2 compound phase in an amount of not less than 80% as measured by Mössbauer spectrum and each having an outer shell in which FeO is present in the form of a layer having a thickness of not more than 5 nm according to the present invention can be produced by subjecting aggregated particles of an iron compound as a starting material whose primary particles have a ratio of [(average deviation of major axis lengths of particles)/(average major axis length of particles)] of not more than 50%, Uc of not more than 1.55, Cg of not less than 0.95, Cg2 of not less than 0.

Abstract: The present invention relates to ferromagnetic particles capable of exhibiting a high purity and excellent magnetic properties from the industrial viewpoints and a process for producing the ferromagnetic particles, and also provides an anisotropic magnet, a bonded magnet and a compacted magnet which are obtained by using the ferromagnetic particles.

Abstract: The present invention relates to ferromagnetic particles comprising an Fe16N2 compound phase in an amount of not less than 70% as measured by Mössbauer spectrum, and at least one metal element X selected from the group consisting of Mn, Ni, Ti, Ga, Al, Ge, Zn, Pt and Si in such an amount that a molar ratio of the metal element X to Fe is 0.04 to 25%, the ferromagnetic particles having a BHmax value of not less than 5 MGOe, and a process for producing the ferromagnetic particles, and further relates to an anisotropic magnet or a bonded magnet which is obtained by magnetically orienting the ferromagnetic particles. The ferromagnetic particles according to the present invention can be produced in an industrial scale and are in the form of Fe16N2 particles comprising different kinds of metal elements having a large BHmax value.

Abstract: A perpendicular magnetic recording medium including at least a soft under layer, an orientation control layer, a magnetic recording layer and a protective layer on a non-magnetic substrate, wherein the orientation control layer is composed of three or more layers including a seed layer, a first intermediate layer and a second intermediate layer sequentially, formed in that order from the substrate side, the crystal grains that constitute the first intermediate layer are epitaxially grown on the crystal grains of the seed layer, the crystal grains that constitute the second intermediate layer are epitaxially grown on the crystal grains of the first intermediate layer, and the crystal grains that constitute the second intermediate layer are finer than the crystal grains that constitute the first intermediate layer.

Abstract: A microwave oscillation element of the present invention includes a lamination main part in which an oscillating layer that is a magnetization free layer and that generates a high frequency electromagnetic field by an excitation of a spin wave, a nonmagnetic intermediate layer, a polarizer layer, and a reference layer that is to be a base magnetic layer of a spin transfer due to application of current are layered in this order. The oscillating layer is made of CoIr, the polarizer layer is configured of CoCr or CoRu; and the nonmagnetic intermediate layer is configured of Cr or Ru. As a result, the efficiency of the spin injection is improved and the microwave oscillation element where the oscillation efficiency is excellent can be realized.

Abstract: The present invention relates to Fe16N2 particles in the form of a single phase which are obtained by subjecting iron oxide or iron oxyhydroxide whose surface may be coated with at least alumina or silica, if required, as a starting material, to reducing treatment and nitridation treatment, a process for producing the Fe16N2 particles in the form of a single phase for a heat treatment time of not more than 36 hr, and further relates to an anisotropic magnet or a bonded magnet which is obtained by magnetically orienting the Fe16N2 particles in the form of a single phase. The Fe16N2 particles according to the present invention can be produced in an industrial scale and have a large BHmax value.

Abstract: The method of the present invention provides a magnetoresistance effect element, which is capable of having a high MR ratio, corresponding to high density recording and being suitably applied to a magnetoresistance device even though a barrier layer is thinned to reduce resistance of the magnetoresistance effect element. The method of producing the magnetoresistance effect element, which includes the barrier layer composed of an oxidized metal, a first magnetic layer contacting one of surfaces of the barrier layer and a second magnetic layer contacting the other surface thereof, comprises the steps of: laminating the barrier layer on the first magnetic layer with using a target composed of the oxidized metal; and laminating the second magnetic layer on the barrier layer. The barrier layer is annealed before laminating the second magnetic layer thereon.

Abstract: An MR element in a CPP structure includes a spacer layer made of Cu, a magnetic pinned layer containing CoFe and a free layer containing CoFe that are laminated to sandwich the spacer layer. The free layer is located below the magnetic pinned layer. The free layer is oriented in a (001) crystal plane, the spacer layer is formed and oriented in a (001) crystal plane on the (001) crystal plane of the free layer. Therefore, in a low resistance area where an area resistivity (AR) of the MR element is, for example, lower than 0.3 ?·?m2, an MR element that has a large variation of a resistance is obtained.

Abstract: The invention provides a magnetic recording medium, and a magnetic recording and reproducing apparatus. The magnetic recording medium includes a substrate 11, an under layer 12 formed on the substrate 11, a magnetic recording layer 13 formed on the under layer 12, and a protective layer 14 formed on the magnetic recording layer 13. The magnetic recording layer 13 is composed of a primary recording layer 14 and a secondary recording layer 15 which are mutually exchange-coupled. The primary recording layer 14 has magnetic grains and a nonmagnetic material that surrounds the magnetic grains, and has a perpendicular magnetic anisotropy. The secondary recording layer 15 is made of a material having a negative crystal magnetic anisotropy and its easy plane of the magnetization is a plane of the medium.

Abstract: An information recording apparatus has a plurality of fine particles forming an array on a plane in close proximity of each other, each of the plural particles including a ferromagnetic metal, a light-emitting device for exciting a near-field light, and a photo-electric conversion element for detecting a near-field light traveled along the fine particles. Summary information may be recorded for plural information recording parts.

Abstract: A microwave oscillation element of the present invention includes a lamination main part in which an oscillating layer that is a magnetization free layer and that generates a high frequency electromagnetic field by an excitation of a spin wave, a nonmagnetic intermediate layer, a polarizer layer, and a reference layer that is to be a base magnetic layer of a spin transfer due to application of current are layered in this order. The oscillating layer is made of CoIr, the polarizer layer is configured of CoCr or CoRu; and the nonmagnetic intermediate layer is configured of Cr or Ru. As a result, the efficiency of the spin injection is improved and the microwave oscillation element where the oscillation efficiency is excellent can be realized.