Abstract: A CoPt-oxide-based in-plane magnetized film having a magnetic coercive force of 2.00 kOe or more and remanent magnetization per unit area Mrt of 2.00 memu/cm2 or more. The in-plane magnetized film for use as a hard bias layer of a magnetoresistive element contains metal Co, metal Pt, and an oxide. The in-plane magnetized film contains the metal Co in an amount of 55 at % or more and less than 95 at % and the metal Pt in an amount of more than 5 at % and 45 at % or less relative to a total of metal components of the in-plane magnetized film, and contains the oxide in an amount of 10 vol % or more and 42 vol % or less relative to a whole amount of the in-plane magnetized film. The in-plane magnetized film has a thickness of 20 nm or more and 80 nm or less.

Abstract: Provided is a magnetic recording medium having a large magnetocrystalline anisotropy constant Ku and a high coercivity Hc as well as a sputtering target used for producing such a magnetic recording medium. A Pt-oxide-based sputtering target consists of 60 vol % or more and less than 100 vol % of a Pt-base alloy phase and more than 0 vol % and 40 vol % or less of an oxide, where the Pt-base alloy phase contains 50 at % or more and 100 at % or less of Pt.

Abstract: An in-plane magnetized film for use as a hard bias layer of a magnetoresistive effect element contains metal Co, metal Pt, and an oxide and has a thickness of 20 nm or more and 80 nm or less, wherein: the in-plane magnetized film contains the metal Co in an amount of 45 at% or more and 80 at% or less and the metal Pt in an amount of 20 at% or more and 55 at% or less relative to a total of metal components of the in-plane magnetized film; the in-plane magnetized film contains the oxide in an amount of 3 vol% or more and 25 vol% or less relative to a whole amount of the in-plane magnetized film; and the in-plane direction average grain diameter of magnetic crystal grains of the in-plane magnetized film is 15 nm or more and 30 nm or less.

Abstract: An in-plane magnetized film multilayer structure for use as a hard bias layer of a magnetoresistive effect element contains a plurality of in-plane magnetized films and a nonmagnetic intermediate layer. The nonmagnetic intermediate layer is disposed between the in-plane magnetized films, and the in-plane magnetized films adjacent across the nonmagnetic intermediate layer are coupled by a ferromagnetic coupling. Each of the in-plane magnetized films contains metal Co and metal Pt, and contains the metal Co in an amount of 45 at % or more and 80 at % or less and the metal Pt in an amount of 20 at % or more and 55 at % or less relative to a total of metal components of the each of the in-plane magnetized films. A total thickness of the plurality of in-plane magnetized films is 30 nm or more.

Abstract: Provided is a sputtering target to be used for forming a granular magnetic thin film in which FePt magnetic grains are isolated by an oxide and which constitutes a heat-assisted magnetic recording medium having enhanced uniaxial magnetic anisotropy, thermal stability, and SNR (signal-to-noise ratio). The sputtering target for a heat-assisted magnetic recording medium contains an FePt alloy and a nonmagnetic material as main components, where the nonmagnetic material is an oxide having a melting point of 800° C. or higher and 1100° C. or lower.

Abstract: Provided is a perpendicular magnetic recording medium that exhibits improved thermal stability and achieves reduction in switching magnetic field by providing a cap layer having characteristics (characteristics contributing to reducing switching magnetic field of the perpendicular magnetic recording medium as well as to improving thermal stability thereof) superior to existing cap layers. A perpendicular magnetic recording layer (24) has a granular structure which comprises Co- Pt-alloy magnetic crystal grains (24A) and a non-magnetic grain boundary oxide (24B). A cap layer (26) has a granular structure which comprises Co-Pt-alloy magnetic crystal grains (26A) and a magnetic grain boundary oxide (26B). The Co- Pt -alloy magnetic crystal grains (26A) in the cap layer (26) contain 65-90 at % of Co and 10-35 at % of Pt. The magnetic grain boundary oxide (26B) is included in a volume fraction of 5-40 vol % with respect to the total volume of the cap layer (26).

Abstract: A CoPt-oxide-based in-plane magnetized film having a magnetic coercive force of 2.00 kOe or more and remanent magnetization per unit area Mrt of 2.00 memu/cm2 or more. The in-plane magnetized film for use as a hard bias layer of a magnetoresistive element contains metal Co, metal Pt, and an oxide. The in-plane magnetized film contains the metal Co in an amount of 55 at % or more and less than 95 at % and the metal Pt in an amount of more than 5 at % and 45 at % or less relative to a total of metal components of the in-plane magnetized film, and contains the oxide in an amount of 10 vol % or more and 42 vol % or less relative to a whole amount of the in-plane magnetized film. The in-plane magnetized film has a thickness of 20 nm or more and 80 nm or less.

Abstract: Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc. The sputtering target is a sputtering target that contains metallic Co, metallic Pt, and an oxide, wherein the sputtering target contains no metallic Cr except inevitable impurities, the oxide is B2O3 and the sputtering target comprises 10 to 50 vol % of the oxide.

Abstract: For a further high capacity, provided is a sputtering target for a magnetic recording medium that can form a magnetic thin film having enhanced uniaxial magnetic anisotropy, reduced intergranular exchange coupling, and improved thermal stability and SNR (signal-to-noise ratio). The sputtering target for a magnetic recording medium, comprises: a metal phase containing Pt and at least one or more selected from Cu and Ni, with the balance being Co and incidental impurities; and an oxide phase containing at least B2O3.

Abstract: Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc. The sputtering target is a sputtering target that contains metallic Co, metallic Pt, and an oxide, wherein the sputtering target contains no metallic Cr except inevitable impurities, the oxide has B2O3, and the sputtering target comprises 10 to 50 vol % of the oxide.

Abstract: A sputtering target for magnetic recording media capable of producing a magnetic thin film in which the magnetic crystal grains are micronized and the distance between the centers of the grains is reduced while good magnetic properties are maintained. The target including metallic Pt and an oxide, with the balance being metallic Co and inevitable impurities, wherein the Co is contained in a range of 70 at % to 90 at % and the Pt is contained in a range of 10 at % to 30 at % relative to a total of metallic components in the sputtering target for magnetic recording media, the oxide is contained in a range of 26 vol % to 40 vol % relative to a total volume of the sputtering target for magnetic recording media, and the oxide is composed of B2O3 and one or more high-melting-point oxides having a melting point of 1470° C. or higher and 2800° C. or lower.

Abstract: A sputtering target that can be used for forming a buffer layer that enables magnetic crystal grains in a magnetic recording layer granular film to be well separated when the magnetic recording layer granular film is stacked above a Ru underlayer. The target contains a metal and an oxide, wherein: the contained metal becomes a nonmagnetic metal including an hcp structure if the entirety of the contained metal is made into a single metal, the lattice constant “a” of the hcp structure included in the nonmagnetic metal being 2.59 ? or more and 2.72 ? or less; the contained metal includes 4 at % or more of metallic Ru relative to the whole amount of the contained metal; and the sputtering target contains 20 vol % or more and 50 vol % or less of the oxide relative to the entire sputtering target, the melting point of the contained oxide being 1700° C. or more.

Abstract: Through the present invention, a thin film containing an FePt-based alloy and carbon, the thin film being capable of being used as a magnetic recording medium, is enabled to be formed using one target, and amount of particles is enabled to be reduced. An FePt—C-based sputtering target containing Fe, Pt, and C, wherein the FePt—C-based sputtering target has a structure in which a C phase substantially being C is dispersed in an FePt-based alloy phase containing 33 mol % or more and 60 mol % or less of Pt with the balance substantially being Fe, an average value of the size indices a of the C phase is 4.0 ?m or more and 9.0 ?m or less, and an average value of the nonspherical indices b of the C phase is 3.0 or more.

Abstract: A sputtering target for magnetic recording media capable of producing a magnetic thin film in which the magnetic crystal grains are micronized and the distance between the centers of the grains is reduced while good magnetic properties are maintained. The target including metallic Pt and an oxide, with the balance being metallic Co and inevitable impurities, wherein the Co is contained in a range of 70 at % to 90 at % and the Pt is contained in a range of 10 at % to 30 at % relative to a total of metallic components in the sputtering target for magnetic recording media, the oxide is contained in a range of 26 vol % to 40 vol % relative to a total volume of the sputtering target for magnetic recording media, and the oxide is composed of B2O3 and one or more high-melting-point oxides having a melting point of 1470° C. or higher and 2800° C. or lower.

Abstract: Through the present invention, a thin film containing an FePt-based alloy and carbon, the thin film being capable of being used as a magnetic recording medium, is enabled to be formed using one target, and amount of particles is enabled to be reduced. An FePt—C-based sputtering target containing Fe, Pt, and C, wherein the FePt—C-based sputtering target has a structure in which a C phase substantially being C is dispersed in an FePt-based alloy phase containing 33 mol % or more and 60 mol % or less of Pt with the balance substantially being Fe, an average value of the size indices a of the C phase is 4.0 ?m or more and 9.0 ?m or less, and an average value of the nonspherical indices b of the C phase is 3.0 or more.

Abstract: An FePt—C-based sputtering target containing Fe, Pt, and C, wherein the FePt—C-based sputtering target has a structure in which primary particles of C that contain unavoidable impurities are dispersed in an FePt-based alloy phase containing 33 at % or more and 60 at % or less of Pt with the balance being Fe and unavoidable impurities, the primary particles of C being dispersed so as not to be in contact with each other.

Abstract: Provided is a sputtering target with which it is possible to form a magnetic thin film having a high coercive force Hc. The sputtering target is a sputtering target that contains metallic Co, metallic Pt, and an oxide, wherein the sputtering target contains no metallic Cr except inevitable impurities, the oxide has B2O3 and the sputtering target comprises 10 to 50 vol % of the oxide.

Abstract: An FePt-based sputtering target contains Fe, Pt, and a metal oxide, and further contains one or more kinds of metal elements other than Fe and Pt, wherein the FePt-based sputtering target has a structure in which an FePt-based alloy phase and a metal oxide phase containing unavoidable impurities are mutually dispersed, the FePt-based alloy phase containing Pt in an amount of 40 at % or more and less than 60 at % and the one or more kinds of metal elements in an amount of more than 0 at % and 20 at % or less with the balance being Fe and unavoidable impurities and with the total amount of Pt and the one or more kinds of metal elements being 60 at % or less, and wherein the metal oxide is contained in an amount of 20 vol % or more and 40 vol % or less based on the total amount of the target.

Abstract: A process for producing an FePt-based sputtering target includes adding C powder containing unavoidable impurities and metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and 60 at % or less with the balance being Fe and unavoidable impurities so that the C powder and the metal oxide powder are contained to satisfy: 0<??20; 10??<40; and 20??+??40, where ? and ? represent contents of the C powder and the metal oxide powder by vol %, respectively, based on a total amount of the FePt-based alloy powder, the C powder, and the metal oxide powder, followed by mixing the FePt-based alloy powder, the C powder, and the metal oxide powder to produce a powder mixture.

Abstract: A process for producing an FePt-based sputtering target includes adding metal oxide powder containing unavoidable impurities to FePt-based alloy powder containing Pt in an amount of 40 at % or more and less than 60 at % and one or more kinds of metal elements other than Fe and Pt in an amount of more than 0 at % and 20 at % or less with the balance being Fe and unavoidable impurities and with a total amount of Pt and the one or more kinds of metal elements being 60 at % or less so that the metal oxide powder accounts for 20 vol % or more and 40 vol % or less of a total amount of the FePt-based alloy powder and the metal oxide powder, followed by mixing the FePt-based alloy powder and the metal oxide powder to produce a powder mixture.