Abstract: A perpendicular magnetic recording medium comprises a soft-magnetic backing layer formed on a substrate, an orientation control layer formed on the soft-magnetic backing layer, a first foundation layer of a continuous film of Ru or a Ru alloy formed on the orientation control layer, a second foundation layer including a plurality of crystal grains of Ru or a Ru alloy formed on the first foundation layer with a gap separating the plurality of crystal grains from each other, and a recording layer including a plurality of magnetic particles formed on the second foundation layer respectively in correspondence to the plurality of crystal grains, each of the magnetic particles having an easy axis of magnetization in a direction generally perpendicular to a substrate surface, and a non-magnetic grain boundary phase isolating said plurality of magnetic particles from each other, wherein the first foundation layer comprises a plurality of crystal grains formed in contact with each other at respective grain boundaries,

Abstract: A perpendicular magnetic recording medium is disclosed that includes a recording layer having a columnar granular structure possessing an appropriate diameter distribution and uniform arrangement of magnetic particles. The perpendicular magnetic recording medium includes a substrate, and a soft-magnetic underlayer, a seed layer, an underlayer, a recording layer, a protection film, and a lubrication layer stacked on the substrate in order. The underlayer includes granular crystals formed from Ru or a Ru alloy and interstices separating the granular crystals from each other so as to isolate individual granular crystals. A continuing film formed from Ru or Ru alloys may be provided below the underlayer.

Abstract: A second thin film having a second thickness is overlaid on a first thin film having a first thickness in a first laminate unit. The first thin film is made of nonmagnetic noble metal atoms. The second thin film is made of magnetic atoms. A fourth thin film having a fourth thickness different from the second thickness is overlaid on a third thin film having a third thickness different from the first thickness in a second laminate unit. The third thin film is made of the nonmagnetic noble metal atoms. The fourth thin film is made of the magnetic atoms. The total saturation magnetization Ms and the total anisotropic magnetic field Hk can be adjusted by changing the numbers of the first and second thin films.

Abstract: 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 Ru.

Abstract: According to an aspect of an embodiment, a magnetic recording medium includes: a soft magnetic underlayer disposed on a substrate; a foundation layer on the soft magnetic underlayer, the foundation layer including a plurality of Ru crystal grains isolated from each other at an upper portion of the foundation layer; a first magnetic layer including a plurality of magnetic crystal grains on the plurality of the Ru crystal grains of the foundation layer; and a second magnetic layer disposed on the plurality of magnetic crystal grains of the first magnetic layer, the second magnetic layer including a plurality of magnetic crystal grains having axes of easy magnetization in the direction perpendicular to the major surface of the substrate and nonmagnetic materials interposed between the crystal grains, the magnetic crystal grains of the first magnetic layer having a smaller grain size than those of the second magnetic layer.

Abstract: A perpendicular magnetic recording medium having a substrate, a soft magnetic buffer layer formed on the substrate, an Ru/Ru alloy underlayer formed on the soft magnetic buffer layer, the Ru/Ru alloy underlayer including Ru or a Ru alloy, a recording layer formed on the Ru/Ru alloy underlayer, the recording layer including at least a layer including a plurality of magnetic particles having an easy axis oriented perpendicular to the substrate, and a non-magnetic material surrounding the plural magnetic particles, and a layered structure interposed between the soft magnetic buffer layer and the Ru/Ru alloy underlayer, the layered structure including at least an Ru/Ru alloy crystalline structure film including Ru or a Ru alloy, a first polycrystalline film including Ru or a Ru alloy, and a second polycrystalline film.

Abstract: A perpendicular magnetic recording medium includes a substrate, a first underlayer formed over the substrate and formed of ruthenium or a ruthenium alloy with crystal grains growing approximately perpendicular to the substrate and isolated from one another in an in-plane direction by a first air gap, a recording layer placed over the first underlayer and formed of magnetic crystal grains growing approximately perpendicular to the substrate and isolated one another in the in-plane direction by a second air gap, and a grain size dispersion preventing layer inserted between the recording layer and the first underlayer, the grain size dispersion preventing layer including crystal grains of a cobalt-based alloy growing approximately perpendicular to the substrate and an oxide isolating the crystal grains of the cobalt-based alloy from one another in the in-plane direction.

Abstract: A perpendicular magnetic recording medium comprises a soft-magnetic backing layer formed on a substrate, an orientation control layer formed on the soft-magnetic backing layer, a first foundation layer of a continuous film of Ru or a Ru alloy formed on the orientation control layer, a second foundation layer including a plurality of crystal grains of Ru or a Ru alloy formed on the first foundation layer with a gap separating the plurality of crystal grains from each other, and a recording layer including a plurality of magnetic particles formed on the second foundation layer respectively in correspondence to the plurality of crystal grains, each of the magnetic particles having an easy axis of magnetization in a direction generally perpendicular to a substrate surface, and a non-magnetic grain boundary phase isolating said plurality of magnetic particles from each other, wherein the first foundation layer comprises a plurality of crystal grains formed in contact with each other at respective grain boundaries,

Abstract: 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.

Abstract: A higher value of an anistropic magnetic feild can be acquired by using a magnetic material where Cr is not added as a material of a magnetic layer on which magnetic data is recorded. A magnetic recording medium can be manufactured through the processes of laminating an underlayer cosisting opf Cr-based non-magnetic material on a substrate, and then laminating, on this underlayer, a magnetic layer consisting of an alloy of at least one kind of non-magnetic material that is different from Cr and Co.

Abstract: Magnetic crystalline grains are spaced from each other on a base layer a polycrystalline structure. The magnetic crystalline grains are made of an ordered alloy. The ordered alloy serves to ensure the crystalline magnetic anisotropy energy larger than that of Co alloy in the magnetic crystalline grains. Such crystalline magnetic anisotropy energy reaches over 1×106J/m3, for example. A sufficient magnetic crystalline magnetic anisotropy energy serves to reliably maintain the magnetization in finely structured magnetic crystalline grains. The ordered alloy may have the L10 structure, for example. The ordered alloy may include of Fe50Pt50 (atom %), Fe50Pd50 (atom %), Co50Pt50 (atom %), and the like.

Abstract: A perpendicular magnetic recording medium is disclosed that includes a substrate, an underlayer formed of one of Ru and a Ru alloy on the substrate, and a recording layer formed on the underlayer. The underlayer includes multiple crystal grains extending in a direction perpendicular to the surface of the substrate, the crystal grains being separated from each other by a first air gap part. The recording layer includes multiple magnetic particles deposited on the crystal grains of the underlayer, the magnetic particles being separated from each other by a second air gap part.

Abstract: First magnetic crystalline grains are located at spaced positions on the surface of a base layer in a polycrystalline structure film. Magnetic interaction can reliably be prevented between the adjacent first magnetic crystalline grains. An amorphous material or a non-magnetic material covers over the first magnetic crystalline grains. An orientation controlling layer covering over the first magnetic crystalline grains and the amorphous or non-magnetic material on the base layer. Second magnetic crystalline grains are located at spaced locations on the surface of the orientation controlling layer. The orientation controlling layer serves to set the orientation in a predetermined direction in the second magnetic crystalline grains. Since the orientation of the magnetic crystalline grains can be aligned in a predetermined direction, the magnetic field of a sufficient intensity can be leaked out of the polycrystalline structure film.

Abstract: A magnetic recording medium includes an underlayer formed on a substrate and a magnetic layer formed by epitaxial growth on the underlayer. The underlayer is made of Cr based substance, and the magnetic layer is made of Co based magnetic substance. The magnetic layer further includes a plurality of layers, each made of Co based alloy including at least one of oxide and nitride as additional content.

Abstract: A perpendicular magnetic recording medium for enabling high density recording is disclosed. The perpendicular magnetic recording medium includes a substrate on which a soft magnetic underlayer, a seed layer made of a non-crystalline material, an underlayer made of Ru or an Ru alloy including Ru as a main component, and a recording layer including a first magnetic layer and a second magnetic layer. The first and second magnetic layers include a plurality of magnetic grains having easy magnetization axes in a substantially perpendicular direction with respect to the substrate surface, and first and second nonmagnetic non-soluble phases segregating the magnetic grains of the first and second magnetic layers, respectively. The first magnetic layer includes the first non-soluble phase at a first atomic concentration that is higher than a second atomic concentration of the second non-soluble phase in the second magnetic layer.

Abstract: A first group of atoms is first deposited for forming a multilayered structure film. The atoms are subjected to heat treatment to form a first polycrystalline layer. A second group of atoms is deposited on the surface of the first polycrystalline layer so as to form a second polycrystalline layer having a thickness larger than the thickness of the first polycrystalline layer. A third group of atoms is deposited on the surface of the second polycrystalline layer so as to form a magnetic polycrystalline layer. The method enables a reliable prevention of migration of atoms in the first group during the deposition of the first group. This enables establishment of fine and uniform crystal grains in the first polycrystalline layer. Migration can still be suppressed during the deposition of the second group. Fine and uniform crystal grains can thus be established in the second polycrystalline layer.

Abstract: A layered polycrystalline structure includes a seed crystal or Cr layer containing non-magnetic Cr atoms. A non-magnetic crystal layer such as a Co65Cr35 layer is formed on the exposed surface of the seed crystal layer. A magnetic crystal layer such as a co88Pt12 layer is formed on the exposed surface of the non-magnetic crystal layer. Heat treatment induces the diffusion of the Cr atoms along the grain boundaries within the magnetic crystal layer. Walls of a non-magnetic material can be established along the grain boundaries in the magnetic crystal layer. The diffusion of the Cr atoms can sufficiently be suppressed within the lattices of the magnetic crystal grains. Generation of an incomplete non-magnetic region can thus be restrained to the utmost within the magnetic crystal layer. Noise can be reduced in reproduction of a magnetic information data.

Abstract: A perpendicular magnetic recording medium is disclosed that includes a recording layer having a columnar granular structure possessing an appropriate diameter distribution and uniform arrangement of magnetic particles. The perpendicular magnetic recording medium includes a substrate, and a soft-magnetic underlayer, a seed layer, an underlayer, a recording layer, a protection film, and a lubrication layer stacked on the substrate in order. The underlayer includes granular crystals formed from Ru or a Ru alloy and interstices separating the granular crystals from each other so as to isolate individual granular crystals. A continuing film formed from Ru or Ru alloys may be provided below the underlayer.

Abstract: A perpendicular magnetic recording medium is disclosed that includes a recording layer having a columnar granular structure possessing an appropriate diameter distribution and uniform arrangement of magnetic particles. The perpendicular magnetic recording medium includes a substrate, and a soft-magnetic backup layer, a seed layer, an underlayer, a recording layer, a protection film, and a lubrication layer stacked on the substrate in order. The underlayer includes granular crystals formed from Ru or a Ru alloy and interstices separating the granular crystals from each other so as to isolate individual granular crystals. A continuing film formed from Ru or Ru alloys may be provided below the underlayer.

Abstract: First atoms are subjected to heat treatment after deposition so as to form a first polycrystalline layer. Second atoms are deposited on the surface of the first polycrystalline layer so as to form a second polycrystalline layer having a thickness larger than that of the first polycrystalline layer. The method enables a reliable prevention of migration of the first atoms during the deposition of the first atoms. Since the first atoms are only allowed to deposit at a smaller amount relative to the overall thickness of a multilayered structure film, fine and uniform crystal grains can be established in the first polycrystalline layer. The deposition of the second atoms can be realized to a predetermined thickness without inducing migration. Fine and uniform crystal grains can also be established in the second polycrystalline layer. Enlargement of the crystal grains can reliably be avoided in this manner.