Magnetic recording medium and magnetic recording device

Abstract

To provide a magnetic recording medium and a magnetic recording device capable of improving recording density.SOLUTION: According to the embodiment, a magnetic recording medium includes first to third magnetic regions. The second magnetic region is provided between the third magnetic region and the first magnetic region. A first composition ratio of a PT atomic concentration to a Co atomic concentration in the first magnetic region and a third composition ratio of a PT atomic concentration to a Co atomic concentration in the third magnetic region is higher than a second composition ratio of a Pt atomic concentration to a Co atomic concentration in the second magnetic region. A distance along a first direction between the second magnetic region and the first magnetic region is longer than a distance along the first direction between the third magnetic region and the second magnetic region. Or, the first magnetic region is separated from the second magnetic region and the third magnetic region is in contact with the second magnetic region.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a magnetic recording medium and a magnetic recording device.

Background Art

[0002] Information is recorded on a magnetic recording medium such as a HDD (Hard Disk Drive) using a magnetic head. In the magnetic recording medium, an improvement in recording density is desired.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments of the present invention provide a magnetic recording medium and a magnetic recording device capable of improving the recording density.

Means for Solving the Problems

[0005] According to one embodiment, the magnetic recording medium includes a first magnetic region, a second magnetic region, and a third magnetic region. The second magnetic region lies between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Pt atom concentration in the first magnetic region to the first Co atom concentration in the first magnetic region is higher than the second composition ratio of the second Pt atom concentration in the second magnetic region to the second Co atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. The first distance along the first direction between the second magnetic region and the first magnetic region is longer than the second distance along the first direction between the third magnetic region and the second magnetic region. Alternatively, the first magnetic region is separated from the second magnetic region, and the third magnetic region is in contact with the second magnetic region. [Brief explanation of the drawing]

[0006] [Figure 1] Figure 1 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 2] Figures 2(a) to 2(c) are graphs illustrating the characteristics of magnetic recording media. [Figure 3] Figures 3(a) to 3(c) are graphs illustrating the characteristics of magnetic recording media. [Figure 4] Figures 4(a) to 4(c) are graphs illustrating the characteristics of magnetic recording media. [Figure 5] Figure 5 is a graph illustrating the characteristics of a magnetic recording medium. [Figure 6] Figure 6 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 7] Figure 7 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 8] Figure 8 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 9] Figure 9 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 10] Figure 10 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 11] Figure 11 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. [Figure 12] Figure 12 is a schematic perspective view illustrating a magnetic recording device according to the second embodiment. [Figure 13] Figure 13 is a schematic cross-sectional view illustrating a part of a magnetic recording device according to the second embodiment. [Figure 14] Figure 14 is a schematic perspective view illustrating a part of a magnetic recording apparatus according to an embodiment. [Figure 15] Figure 15 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. [Figure 16] Figures 16(a) and 16(b) are schematic perspective views illustrating a part of a magnetic recording apparatus according to an embodiment. [Modes for carrying out the invention]

[0007] (First Embodiment) Figure 1 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 1, the magnetic recording medium 80 according to this embodiment is used together with a magnetic head 110. The magnetic recording medium 80 and the magnetic head 110 are included in the magnetic recording device 150. The magnetic head 110 controls the magnetization of the magnetic recording medium 80. As a result, information is recorded on the magnetic recording medium 80. The magnetic head 110 may be capable of reproducing the recorded information.

[0008] As shown in Figure 1, the magnetic recording medium 80 includes a first magnetic region 81, a second magnetic region 82, and a third magnetic region 83. The first magnetic region 81, the second magnetic region 82, and the third magnetic region 83 are included in the recording layer 80R.

[0009] The second magnetic region 82 is located between the third magnetic region 83 and the first magnetic region 81 in the first direction D1 from the third magnetic region 83 to the first magnetic region 81. The first direction D1 is the Z-axis direction. One direction perpendicular to the Z-axis direction is the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is the Y-axis direction. The first magnetic region 81, the second magnetic region 82, and the third magnetic region 83 are substantially parallel to the X-Y plane. These regions are layered.

[0010] The magnetization of the first magnetic region 81, the magnetization of the second magnetic region 82, and the magnetization of the third magnetic region are along the first direction D1. The magnetic recording medium 80 is a perpendicular magnetization medium.

[0011] For example, the first magnetic region 81, the second magnetic region 82, and the third magnetic region 83 are granular magnetic regions. For example, high-density recording is possible.

[0012] As shown in FIG. 1, the magnetic recording medium 80 may include a non-magnetic substrate 85S and an intermediate layer 84. The third magnetic region 83 is provided between the non-magnetic substrate 85S and the first magnetic region 81. The intermediate layer 84 is provided between the non-magnetic substrate 85S and the third magnetic region 83. The intermediate layer 84 is, for example, soft magnetic. The non-magnetic substrate 85S includes, for example, at least one selected from the group consisting of SiO2 (for example, glass), Al-based alloys, ceramics, and resins. The intermediate layer 84 includes, for example, at least one selected from the group consisting of CoZrNb, CoB, CoTaZr, FeSiAl, FeTaC, CoTaC, NiFe, Fe, FeCoB, FeCoN, and FeTaN.

[0013] As shown in FIG. 1, in the embodiment, the first magnetic region 81 is located between the third magnetic region 83 and the magnetic head 110.

[0014] In the three magnetic regions, the compositions are different from each other. The composition ratios of the three magnetic regions are different from each other. The composition ratio in each of the three magnetic regions may be, for example, an average composition ratio.

[0015] The ratio of the concentration of the first Pt atom in the first magnetic region 81 to the concentration of the first Co atom in the first magnetic region 81 (Pt / Co) is defined as the first composition ratio. The average of the first composition ratio in the first direction D1 is defined as the first average value AC1. The difference between the highest and lowest values ​​of the first composition ratio in the first magnetic region 81 is defined as the first difference ΔC1.

[0016] For example, the first ratio (ΔC1 / AC1) of the first difference ΔC1 to the first average value AC1 is 0.2 or less. That is, in the first magnetic region 81, the composition ratio may change within 20%. The first ratio may also be 0.4 or less.

[0017] The ratio of the second Pt atom concentration in the second magnetic region 82 to the second Co atom concentration in the second magnetic region 82 (Pt / Co) is defined as the second composition ratio. The average of the second composition ratio in the first direction D1 is defined as the second average value AC2. The difference between the highest and lowest values ​​of the second composition ratio in the second magnetic region 82 is defined as the second difference ΔC2.

[0018] For example, the second ratio (ΔC2 / AC2) of the second difference ΔC2 to the second average value AC2 is 0.2 or less. That is, in the second magnetic region 82, the composition ratio may change within 20%. The second ratio may also be 0.4 or less.

[0019] The ratio of the concentration of the third Pt atom in the third magnetic region 83 to the concentration of the third Co atom in the third magnetic region 83 (Pt / Co) is defined as the third composition ratio. The average of the third composition ratio in the first direction D1 is defined as the third average value AC3. The difference between the highest and lowest values ​​of the third composition ratio in the third magnetic region 83 is defined as the third difference ΔC3.

[0020] For example, the third ratio (ΔC3 / AC3) of the third difference ΔC3 to the third average value AC3 is 0.2 or less. That is, in the third magnetic region 83, the composition ratio may change within 20%. The third ratio may also be 0.4 or less.

[0021] In the embodiment, the first composition ratio is higher than the second composition ratio. The third composition ratio is higher than the second composition ratio. For example, in the embodiment, the first average value AC1 is higher than the second average value AC2. The third average value AC3 is higher than the second average value AC2.

[0022] As shown in Figure 1, the distance along the first direction D1 between the second magnetic region 82 and the first magnetic region 81 is defined as the first distance d1. The distance along the first direction D1 between the third magnetic region 83 and the second magnetic region 82 is defined as the second distance d2. In this embodiment, the first distance d1 is longer than the second distance d2. Alternatively, the first magnetic region 81 is separated from the second magnetic region 82, and the third magnetic region 83 is in contact with the second magnetic region 82.

[0023] It was found that a high areal recording density can be obtained with this configuration. As shown in Figure 1, a magnetic head 110 faces one side of the recording layer 80R. A recording magnetic field is applied to the recording layer 80R from the magnetic head 110. At this time, for example, an alternating magnetic field may be applied to the recording layer 80R from the magnetic head 110. The alternating magnetic field is, for example, a high-frequency magnetic field. For example, MAMR (Microwave Assisted Magnetic Recording) may be implemented. The recording magnetic field and alternating magnetic field applied by the magnetic head 110 pass through the first magnetic region 81 and reach the second magnetic region 82 and the third magnetic region 83. According to this embodiment, a magnetic recording medium capable of improving recording density can be provided.

[0024] In this embodiment, as described above, the first distance d1 is longer than the second distance d2. This results in a high areal recording density. This is thought to be because the magnetic properties (including exchange coupling properties) of the three magnetic regions are properly set.

[0025] Because the first distance d1 is longer than the second distance d2, the exchange coupling strengths are different. For example, the first exchange coupling strength between the second magnetic region 82 and the first magnetic region 81 is lower than the second exchange coupling strength between the third magnetic region 83 and the second magnetic region 82.

[0026] For example, even when the first magnetic region 81 is separated from the second magnetic region 82 and the third magnetic region 83 is in contact with the second magnetic region 82, the first exchange coupling strength is lower than the second exchange coupling strength.

[0027] As described above, the composition (e.g., the average composition ratio) in each of the three magnetic regions is different from one another. A high ratio of Pt atom concentration to Co atom concentration (Pt / Co) results in a large anisotropic magnetic field Hk in the magnetic region. A low ratio results in a small anisotropic magnetic field Hk in the magnetic region. The anisotropic magnetic field (e.g., the average anisotropic magnetic field) in each of the three magnetic regions is different from one another.

[0028] For example, the anisotropic magnetic field of one magnetic region can be taken as the average of the anisotropic magnetic fields in the first direction D1. The average of the anisotropic magnetic fields of the first magnetic region 81 in the first direction D1 is defined as the first average anisotropic magnetic field Hk1. The average of the anisotropic magnetic fields of the second magnetic region 82 in the first direction D1 is defined as the second average anisotropic magnetic field Hk2. The average of the anisotropic magnetic fields of the third magnetic region 83 in the first direction D1 is defined as the third average anisotropic magnetic field Hk3.

[0029] In this embodiment, the anisotropic magnetic field of the first magnetic region 81 is greater than that of the second magnetic region 82. The anisotropic magnetic field of the third magnetic region 83 is greater than that of the second magnetic region 82. For example, in this embodiment, the first average anisotropic magnetic field Hk1 is greater than that of the second average anisotropic magnetic field Hk2. The third average anisotropic magnetic field Hk3 is greater than that of the second average anisotropic magnetic field Hk2. This allows for a high areal recording density.

[0030] The following describes an example of simulation results for the magnetic recording medium 80. In the simulation, the anisotropic magnetic fields of the magnetic region (first mean anisotropic magnetic field Hk1, second mean anisotropic magnetic field Hk2, and third mean anisotropic magnetic field Hk3) are changed. The anisotropic magnetic fields reflect the composition ratio described above. In the simulation, the first exchange coupling strength Jex1 and the second exchange coupling strength Jex2 are also changed. The exchange coupling strength is related to the distance described above. When the distance is long, the exchange coupling strength becomes lower.

[0031] Figures 2(a) to 2(c), 3(a) to 3(c), 4(a) to 4(c), and 5 are graphs illustrating the characteristics of magnetic recording media. These figures illustrate the relationship between the anisotropic magnetic field and the exchange coupling strength, and the areal recording density required for proper recording and playback operation.

[0032] In Figures 2(a) to 2(c), the first exchange coupling strength Jex1 is lower than the second exchange coupling strength Jex2. In this example, the first exchange coupling strength Jex1 is between 0.1 and 0.6 times the second exchange coupling strength Jex2. Figures 2(a) to 2(c) correspond to the case where the first distance d1 is longer than the second distance d2. The horizontal axis in Figure 2(a) is Hk1 / Hk2. The horizontal axis in Figure 2(b) is Hk3 / Hk2. The horizontal axis in Figure 2(c) is Hk1 / Hk3. The vertical axis in these figures is the areal recording density ADC.

[0033] In Figures 3(a) to 3(c), the first exchange coupling strength Jex1 is substantially the same as the second exchange coupling strength Jex2. In this example, the first exchange coupling strength Jex1 is between 0.9 and 1.1 times the second exchange coupling strength Jex2. Figures 3(a) to 3(c) correspond to the case where the first distance d1 is substantially the same as the second distance d2. The horizontal axis in Figure 3(a) is Hk1 / Hk2. The horizontal axis in Figure 3(b) is Hk3 / Hk2. The horizontal axis in Figure 3(c) is Hk1 / Hk3. The vertical axis in these figures is the areal recording density ADC.

[0034] In Figures 4(a) to 4(c), the first exchange coupling strength Jex1 is higher than the second exchange coupling strength Jex2. In this example, the first exchange coupling strength Jex1 is more than 1 times the second exchange coupling strength Jex2 and less than or equal to 20 times. Figures 4(a) to 4(c) correspond to the case where the first distance d1 is shorter than the second distance d2. The horizontal axis in Figure 4(a) is Hk1 / Hk2. The horizontal axis in Figure 4(b) is Hk3 / Hk2. The horizontal axis in Figure 4(c) is Hk1 / Hk3. The vertical axis in these figures is the areal recording density ADC.

[0035] As shown in Figures 2(a) to 2(c), when the first exchange coupling strength Jex1 is lower than the second exchange coupling strength Jex2, there are conditions under which a high areal recording density ADC of 0.9 to 1.0 can be obtained. In contrast, as shown in Figures 3(a) to 3(c), when the first exchange coupling strength Jex1 is substantially the same as the second exchange coupling strength Jex2, the areal recording density ADC is 0.8 or less. As shown in Figures 4(a) to 4(c), when the first exchange coupling strength Jex1 is higher than the second exchange coupling strength Jex2, the areal recording density ADC is 0.8 or less.

[0036] Thus, a high surface density is obtained when the first exchange bond strength Jex1 is lower than the second exchange bond strength Jex2. For example, the first exchange bond strength Jex1 is between 0.1 and 0.6 times the second exchange bond strength Jex2. A high surface density is obtained.

[0037] For example, the distance between the first magnetic region 81 and the magnetic head 110 is shorter than the distance between the second magnetic region 82 and the magnetic head 110, and shorter than the distance between the third magnetic region 83 and the magnetic head 110. During recording by the magnetic head 110, the magnetization of the first magnetic region 81 is more easily reversed than the magnetization of the other magnetic regions. The reversed magnetization of the first magnetic region 81 is transmitted to the second magnetic region 82 by a low first exchange coupling strength Jex1. For example, the magnetization of the second magnetic region 82, which has a small second mean anisotropy field Hk2, is effectively reversed by the influence of the magnetization of the first magnetic region 81, which has a large first mean anisotropy field Hk1. On the other hand, a high second exchange coupling strength Jex2 allows the magnetization of the second magnetic region 82, which has a small second mean anisotropy field Hk2, to be transmitted to the third magnetic region 83. For example, even when the third mean anisotropy field Hk3 of the third magnetic region 83 is high, the high second exchange coupling strength Jex2 allows the magnetization of the second magnetic region 82 to be transmitted to the third magnetic region 83. This is thought to result in a high surface density.

[0038] As shown in Figure 2(a), a high areal recording density ADC can be obtained when Hk1 / Hk2 is between 1.4 and 1.7. As shown in Figure 2(b), a high areal recording density ADC can be obtained when Hk3 / Hk2 is between 1.4 and 1.7. As shown in Figure 2(c), a high areal recording density ADC can be obtained when Hk1 / Hk3 is between 0.9 and 1.1.

[0039] The horizontal axis in Figure 5 represents the exchange coupling ratio JR. The exchange coupling ratio JR is the ratio of the first exchange coupling strength Jex1 to the second exchange coupling strength Jex2. In Figure 5, Hk1 > Hk2 and Hk3 > Hk2. As shown in Figure 5, a high areal recording density can be obtained when the exchange coupling ratio JR is between 0.1 and 0.6.

[0040] In the embodiment, for example, the ratio of the first exchange coupling strength to the second exchange coupling strength is preferably 0.1 or more and 0.6 or less. This allows for a high areal recording density.

[0041] In the embodiment, the ratio of the anisotropic magnetic field of the first magnetic region 81 to the anisotropic magnetic field of the second magnetic region 82 is preferably 1.4 or more and 1.7 or less. For example, the ratio of the first average anisotropic magnetic field Hk1 to the second average anisotropic magnetic field Hk2 (Hk1 / Hk2) is preferably 1.4 or more and 1.7 or less. This allows for a high areal recording density. The ratio of the anisotropic magnetic field of the third magnetic region 83 to the anisotropic magnetic field of the second magnetic region 82 is preferably 1.4 or more and 1.7 or less. For example, the ratio of the third average anisotropic magnetic field Hk3 to the second average anisotropic magnetic field Hk2 (Hk3 / Hk2) is preferably 1.4 or more and 1.7 or less. This allows for a high areal recording density. The ratio of the anisotropic magnetic field of the first magnetic region 81 to the anisotropic magnetic field of the third magnetic region 83 is preferably 0.9 or more and 1.1 or less. For example, the ratio of the first mean anisotropic magnetic field Hk1 to the third mean anisotropic magnetic field Hk3 (Hk1 / Hk3) is preferably between 0.9 and 1.1. This allows for a high areal recording density.

[0042] In the embodiment, the first average anisotropic magnetic field Hk1 is preferably, for example, 19000 Oe or more. The first average anisotropic magnetic field Hk1 may be 25000 Oe or less. The second average anisotropic magnetic field Hk2 is preferably, for example, 11000 Oe or more and 15000 Oe or less. The third average anisotropic magnetic field Hk3 is preferably, for example, 18000 Oe or more. The third average anisotropic magnetic field Hk3 may be 25000 Oe or less.

[0043] Thus, in the magnetic recording medium 80 according to this embodiment, the first magnetic region 81, the second magnetic region 82, and the third magnetic region 83 may satisfy the following conditions. The anisotropic magnetic field in the first magnetic region 81 is greater than that of the second magnetic region 82. The anisotropic magnetic field in the third magnetic region 83 is greater than that of the second magnetic region 82. For example, the average of the anisotropic magnetic field in the first magnetic region 81 in the first direction D1 is the first average anisotropic magnetic field Hk1. For example, the first ratio of the first difference between the maximum and minimum values ​​of the anisotropic magnetic field in the first magnetic region 81 to the first average anisotropic magnetic field Hk1 is 0.2 or less. The average of the anisotropic magnetic field in the second magnetic region 82 in the first direction D1 is the second average anisotropic magnetic field Hk2. For example, the second ratio of the second difference between the maximum and minimum values ​​of the anisotropic magnetic field in the second magnetic region 82 to the second average anisotropic magnetic field Hk2 is 0.2 or less. The average of the anisotropic magnetic field in the third magnetic region 83 in the first direction D1 is the third average anisotropic magnetic field Hk3. For example, the third ratio of the third difference between the maximum and minimum values ​​of the anisotropic magnetic field in the third magnetic region 83 to the third mean anisotropic magnetic field Hk3 is 0.2 or less.

[0044] The first mean anisotropic magnetic field Hk1 is greater than the second mean anisotropic magnetic field Hk2. The third mean anisotropic magnetic field Hk3 is greater than the second mean anisotropic magnetic field Hk2. The first distance d1 along the first direction D1 between the second magnetic region 82 and the first magnetic region 81 is longer than the second distance d2 along the first direction D1 between the third magnetic region 83 and the second magnetic region 82. Alternatively, the first magnetic region 81 is separated from the second magnetic region 82, and the third magnetic region 83 is in contact with the second magnetic region 82.

[0045] The first thickness t1 of the first magnetic region 81 (see Figure 1) is, for example, 4 nm to 10 nm. The second thickness t2 of the second magnetic region 82 (see Figure 1) is, for example, 1 nm to 6 nm. The third thickness t3 of the third magnetic region 83 (see Figure 1) is, for example, 4 nm to 10 nm. These thicknesses are lengths along the first direction D1.

[0046] The first distance d1 is, for example, between 0.1 nm and 0.6 nm. The second distance d2 is, for example, between 0 nm and 0.5 nm.

[0047] Figure 6 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 6, in the magnetic recording medium 80A according to this embodiment, at least one of the three magnetic regions includes a plurality of magnetic films. The configuration of the magnetic recording medium 80A, excluding this, may be the same as that of the magnetic recording medium 80.

[0048] As shown in Figure 6, the first magnetic region 81 includes a plurality of first magnetic films 81f. The plurality of first magnetic films 81f are aligned along a first direction D1. The direction from one of the plurality of first magnetic films 81f to another of the plurality of first magnetic films 81f is along the first direction D1.

[0049] The second magnetic region 82 includes a plurality of second magnetic films 82f. The direction from one of the plurality of second magnetic films 82f to another of the plurality of second magnetic films 82f is along the first direction D1. The third magnetic region 83 includes a plurality of third magnetic films 83f. The direction from one of the plurality of third magnetic films 83f to another of the plurality of third magnetic films 83f is along the first direction D1.

[0050] The difference in composition ratio among multiple first magnetic films 81f is, for example, within 20%. The difference in composition ratio among multiple second magnetic films 82f is, for example, within 20%. The difference in composition ratio among multiple third magnetic films 83f is, for example, within 20%.

[0051] Figure 7 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 7, the magnetic recording medium 80B according to this embodiment further includes a first intermediate region 91n and a second intermediate region 92n. The configuration of the magnetic recording medium 80B, excluding these, may be the same as the configuration of the magnetic recording medium 80 or the magnetic recording medium 80A.

[0052] In the magnetic recording medium 80B, the first intermediate region 91n is provided between the second magnetic region 82 and the first magnetic region 81. The first intermediate region 91n is non-magnetic. The second intermediate region 92n is provided between the third magnetic region 83 and the second magnetic region 82. The second intermediate region 92n is non-magnetic.

[0053] The first intermediate region 91n and the second intermediate region 92n each include, for example, at least one selected from the group consisting of Ru, Pt, and C. The thickness of the first intermediate region 91n corresponds to the first distance d1. The thickness of the second intermediate region 92n corresponds to the second distance d2.

[0054] Figure 8 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 8, the magnetic recording medium 80C according to this embodiment includes a first intermediate region 91n. In the magnetic recording medium 80C, the second magnetic region 82 is in contact with the third magnetic region 83. The configuration of the magnetic recording medium 80C, excluding this, may be the same as that of the magnetic recording medium 80 or the magnetic recording medium 80A.

[0055] In the magnetic recording medium 80C, the second distance d2 is 0. Because the second magnetic region 82 is in contact with the third magnetic region 83, the first exchange coupling strength becomes lower than the second exchange coupling strength.

[0056] Figure 9 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 9, the magnetic recording medium 80D according to the embodiment further includes a first intermediate region 91n and a second intermediate magnetic region 92m. The configuration of the magnetic recording medium 80D, excluding these, may be the same as that of the magnetic recording medium 80 or the magnetic recording medium 80A.

[0057] The first intermediate region 91n is located between the second magnetic region 82 and the first magnetic region 81. The first intermediate region 91n is nonmagnetic. The second intermediate magnetic region 92m is located between the third magnetic region 83 and the second magnetic region 82. The second intermediate magnetic region 92m is a continuous magnetic region. The second intermediate magnetic region 92m includes, for example, at least one selected from the group consisting of Cr, Pt, and Pd, and Co. The thickness of the first intermediate region 91n corresponds to the first distance d1. The thickness of the second intermediate magnetic region 92m corresponds to the second distance d2.

[0058] In the magnetic recording medium 80D, the first distance d1 may be the same as the second distance d2, shorter, or longer. The difference between the non-magnetic film and the magnetic film results in a difference in exchange coupling strength. In the magnetic recording medium 80D, the first exchange coupling strength is lower than the second exchange coupling strength.

[0059] In the magnetic recording medium 80D, the second magnetic region 82 and the third magnetic region 83 are granular magnetic regions. The second intermediate magnetic region 92m, the second magnetic region 82, and the third magnetic region 83 can be identified, for example, by electron microscope images. The first magnetic region 81 may also be a granular magnetic region.

[0060] Thus, the magnetic recording medium 80D includes a first magnetic region 81, a second magnetic region 82, a third magnetic region 83, a first intermediate region 91n, and a second intermediate magnetic region 92m. The first intermediate region 91n is located between the second magnetic region 82 and the first magnetic region 81. The second intermediate magnetic region 92m is located between the third magnetic region 83 and the second magnetic region 82. The second intermediate magnetic region 92m is a continuous magnetic region. The first intermediate region 91n is non-magnetic.

[0061] Figure 10 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 10, the magnetic recording medium 80E according to this embodiment includes a first continuous magnetic region 95m. The configuration of the magnetic recording medium 80E, excluding this region, may be the same as that of the magnetic recording medium 80 or the magnetic recording medium 80A.

[0062] In the magnetic recording medium 80E, the first magnetic region 81 is provided between the third magnetic region 83 and the first continuous magnetic region 95m. The first continuous magnetic region 95m includes, for example, at least one selected from the group consisting of Cr, Pt, and Pd, and Co. The first continuous magnetic region 95m is, for example, a cap layer. By providing the first continuous magnetic region 95m, for example, high recording characteristics can be obtained.

[0063] In the magnetic recording medium 80E, the first magnetic region 81 is a granular magnetic region. The second magnetic region 82 and the third magnetic region 83 may also be granular magnetic regions.

[0064] Figure 11 is a schematic cross-sectional view illustrating a magnetic recording medium according to the first embodiment. As shown in Figure 11, in the magnetic recording medium 80F according to this embodiment, another recording layer 80RA is provided in addition to the recording layer 80R described above. The configuration of the magnetic recording medium 80F other than this can be the same as the configuration of any magnetic recording medium described above.

[0065] A non-magnetic substrate 85S is provided between another recording layer 80RA and another recording layer 80R. The other recording layer 80RA includes another first magnetic region 81A, another second magnetic region 82A, and another third magnetic region 83A. A non-magnetic substrate 85S is provided between another first magnetic region 81A and the first magnetic region 81. Another second magnetic region 82A is provided between another first magnetic region 81A and the non-magnetic substrate 85S. Another third magnetic region 83A is provided between another second magnetic region 82A and the non-magnetic substrate 85S. Another intermediate layer 84A may be provided between another third magnetic region 83A and the non-magnetic substrate 85S.

[0066] In the magnetic recording medium 80F, recording layers are provided on each of the two surfaces of the non-magnetic substrate 85S. Another magnetic head 110A faces another first magnetic region 81A.

[0067] (Second Embodiment) The second embodiment relates to a magnetic recording device 150. Figure 12 is a schematic perspective view illustrating a magnetic recording device according to the second embodiment. As shown in Figure 12, the magnetic head 110 is used together with a magnetic recording medium (for example, a magnetic recording medium 80) according to the first embodiment. In this example, the magnetic head 110 includes a recording unit 60 and a playback unit 70. The recording unit 60 of the magnetic head 110 records information on the magnetic recording medium 80. The playback unit 70 reproduces the information recorded on the magnetic recording medium 80.

[0068] The magnetic recording medium 80 includes, for example, a non-magnetic substrate 85S and a recording layer 80R provided on the non-magnetic substrate 85S. The magnetization 80M of the recording layer 80R is controlled by the recording unit 60.

[0069] The regeneration unit 70 includes, for example, a first regeneration magnetic shield 72a, a second regeneration magnetic shield 72b, and a magnetic regeneration element 71. The magnetic regeneration element 71 is provided between the first regeneration magnetic shield 72a and the second regeneration magnetic shield 72b. The magnetic regeneration element 71 is capable of outputting a signal corresponding to the magnetization 80M of the recording layer 80R.

[0070] As shown in Figure 12, the magnetic recording medium 80 moves relative to the magnetic head 110 in the direction of the medium movement direction 85. The magnetic head 110 controls the information corresponding to the magnetization 80M of the recording layer 80R at any given position. The magnetic head 110 reproduces the information corresponding to the magnetization 80M of the recording layer 80R at any given position.

[0071] As already explained, in the magnetic recording device 150, the first magnetic region 81 is located between the third magnetic region 83 and the magnetic head 110 (see Figure 1). The magnetic head 110 is capable of recording. During the recording operation, an alternating magnetic field is applied from the magnetic head 110 to the magnetic recording medium 80 (between it and the recording layer 80R). The recording magnetic field is applied from the magnetic head 110 to the magnetic recording medium 80 (recording layer 80R).

[0072] Figure 13 is a schematic cross-sectional view illustrating a part of a magnetic recording device according to the second embodiment. Figure 13 illustrates a magnetic head 110. The magnetic head 110 includes a first magnetic pole 31, a second magnetic pole 32, and a magnetic element 20. The magnetic element 20 is provided between the first magnetic pole 31 and the second magnetic pole 32.

[0073] For example, the magnetic element 20 includes a first magnetic layer 21, a second magnetic layer 22, a third magnetic layer 23, and a fourth magnetic layer 24. The first magnetic layer 21 is provided between the first magnetic pole 31 and the second magnetic pole 32. The second magnetic layer 22 is provided between the first magnetic layer 21 and the second magnetic pole 32. The third magnetic layer 23 is provided between the second magnetic layer 22 and the second magnetic pole 32. The fourth magnetic layer 24 is provided between the third magnetic layer 23 and the second magnetic pole 32.

[0074] For example, the magnetic element 20 includes a first non-magnetic layer 41, a second non-magnetic layer 42, a third non-magnetic layer 43, a fourth non-magnetic layer 44, and a fifth non-magnetic layer 45. The first non-magnetic layer 41 is provided between the first magnetic pole 31 and the first magnetic layer 21. The second non-magnetic layer 42 is provided between the first magnetic layer 21 and the second magnetic layer 22. The third non-magnetic layer 43 is provided between the second magnetic layer 22 and the third magnetic layer 23. The fourth non-magnetic layer 44 is provided between the third magnetic layer 23 and the fourth magnetic layer 24. The fifth non-magnetic layer 45 is provided between the fourth magnetic layer 24 and the second magnetic pole 32.

[0075] In one example, the first non-magnetic layer 41 includes at least one selected from the group consisting of Cu, Au, Cr, V, Al, and Ag. The second non-magnetic layer 42 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. The third non-magnetic layer 43 includes at least one selected from the group consisting of Cu, Au, Cr, V, Al, and Ag. The fourth non-magnetic layer 44 includes at least one selected from the group consisting of Cu, Au, Cr, V, Al, and Ag. The fifth non-magnetic layer 45 includes at least one selected from the group consisting of Ru, Ir, Ta, Rh, Pd, Pt, and W. In such a configuration, for example, a stable alternating magnetic field is easily obtained.

[0076] As shown in Figure 13, during the recording operation, a current ic is supplied to the magnetic element 20. The current ic flows from the first magnetic pole 31 to the second magnetic pole 32. The electron current je flows from the second magnetic pole 32 to the first magnetic pole 31.

[0077] Figure 14 is a schematic perspective view illustrating a part of a magnetic recording apparatus according to an embodiment. Figure 14 illustrates a head slider. The magnetic head 110 is mounted on a head slider 159. The head slider 159 includes, for example, Al2O3 / TiC. The head slider 159 moves relative to the magnetic recording medium, either floating above or in contact with it.

[0078] The head slider 159 has, for example, an air inlet side 159A and an air outlet side 159B. The magnetic head 110 is positioned on the side of the air outlet side 159B of the head slider 159. As a result, the magnetic head 110 moves relative to the magnetic recording medium while floating above or in contact with it.

[0079] Figure 15 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. Figures 16(a) and 16(b) are schematic perspective views illustrating a part of a magnetic recording apparatus according to an embodiment. As shown in Figure 15, a rotary actuator is used in the magnetic recording device 150 according to this embodiment. The recording medium disk 180 is mounted on a spindle motor 180M. The recording medium disk 180 rotates in the direction of arrow AR by the spindle motor 180M. The spindle motor 180M responds to a control signal from the drive unit control. The magnetic recording device 150 according to this embodiment may include a plurality of recording medium disks 180. The magnetic recording device 150 may also include a recording medium 181. The recording medium 181 is, for example, an SSD (Solid State Drive). For example, a non-volatile memory such as flash memory is used for the recording medium 181. For example, the magnetic recording device 150 may also be a hybrid HDD (Hard Disk Drive).

[0080] The head slider 159 records and plays back information to be recorded on the recording medium disk 180. The head slider 159 is located at the tip of a thin-film suspension 154. A magnetic head according to this embodiment is located near the tip of the head slider 159.

[0081] As the recording medium disk 180 rotates, the pressing pressure from the suspension 154 and the pressure generated on the media-facing surface (ABS) of the head slider 159 are balanced. The distance between the media-facing surface of the head slider 159 and the surface of the recording medium disk 180 becomes a predetermined amount of levitation. In this embodiment, the head slider 159 may be in contact with the recording medium disk 180. For example, a contact-running type may be applied.

[0082] The suspension 154 is connected to one end of an arm 155 (for example, an actuator arm). The arm 155 has, for example, a bobbin section. The bobbin section holds a drive coil. A voice coil motor 156 is provided at the other end of the arm 155. The voice coil motor 156 is a type of linear motor. The voice coil motor 156 includes, for example, a drive coil and a magnetic circuit. The drive coil is wound around the bobbin section of the arm 155. The magnetic circuit includes a permanent magnet and an opposing yoke. The drive coil is provided between the permanent magnet and the opposing yoke. The suspension 154 has one end and the other end. A magnetic head is provided at one end of the suspension 154. The arm 155 is connected to the other end of the suspension 154.

[0083] The arm 155 is held by ball bearings. Ball bearings are provided at two locations, above and below the bearing portion 157. The arm 155 can rotate and slide by a voice coil motor 156. The magnetic head can move to any position on the recording medium disk 180.

[0084] Figure 16(a) illustrates a part of the configuration of a magnetic recording device and is an enlarged perspective view of the head stack assembly 160. Figure 16(b) is a perspective view illustrating a magnetic head assembly (head gimbal assembly: HGA) 158, which is part of the head stack assembly 160.

[0085] As shown in Figure 16(a), the head stack assembly 160 includes a bearing section 157, a head gimbal assembly 158, and a support frame 161. The head gimbal assembly 158 extends from the bearing section 157. The support frame 161 extends from the bearing section 157. The direction in which the support frame 161 extends is opposite to the direction in which the head gimbal assembly 158 extends. The support frame 161 supports the coil 162 of the voice coil motor 156.

[0086] As shown in Figure 16(b), the head gimbal assembly 158 includes an arm 155 extending from a bearing portion 157 and a suspension 154 extending from the arm 155.

[0087] A head slider 159 is provided at the tip of the suspension 154. A magnetic head according to the embodiment is provided on the head slider 159.

[0088] The magnetic head assembly (head gimbal assembly) 158 according to the embodiment includes a magnetic head according to the embodiment, a head slider 159 on which the magnetic head is provided, a suspension 154, and an arm 155. The head slider 159 is provided at one end of the suspension 154. The arm 155 is connected to the other end of the suspension 154.

[0089] The suspension 154 may have, for example, lead wires (not shown) for recording and reproducing signals. The suspension 154 may also have, for example, lead wires (not shown) for heaters for adjusting the amount of levitation. The suspension 154 may also have, for example, lead wires (not shown) for an oscillator or the like. These lead wires are electrically connected to a plurality of electrodes provided on the magnetic head.

[0090] In the magnetic recording device 150, a signal processing unit 190 is provided. The signal processing unit 190 records and reproduces signals on a magnetic recording medium using a magnetic head. The input and output lines of the signal processing unit 190 are connected, for example, to the electrode pads of the head gimbal assembly 158 and are electrically connected to the magnetic head.

[0091] The magnetic recording apparatus 150 according to the embodiment includes a magnetic recording medium, a magnetic head according to the embodiment, a movable part, a position control unit, and a signal processing unit. The movable part allows the magnetic recording medium and the magnetic head to move relative to each other while separated or in contact. The position control unit aligns the magnetic head to a predetermined recording position on the magnetic recording medium. The signal processing unit records and reproduces signals on the magnetic recording medium using the magnetic head.

[0092] For example, a recording medium disk 180 is used as the magnetic recording medium. The movable part includes, for example, a head slider 159. The position control unit includes, for example, a head gimbal assembly 158.

[0093] The embodiment may include the following configuration (e.g., proposed technical details). (Composition 1) The first magnetic region and, The second magnetic region, The third magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Pt atom concentration in the first magnetic region to the first Co atom concentration in the first magnetic region is higher than the second composition ratio of the second Pt atom concentration in the second magnetic region to the second Co atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. A magnetic recording medium wherein the first distance along the first direction between the second magnetic region and the first magnetic region is longer than the second distance along the first direction between the third magnetic region and the second magnetic region, or the first magnetic region is separated from the second magnetic region and the third magnetic region is in contact with the second magnetic region.

[0094] (Configuration 2) The magnetic recording medium according to configuration 1, wherein the first exchange coupling strength between the second magnetic region and the first magnetic region is lower than the second exchange coupling strength between the third magnetic region and the second magnetic region.

[0095] (Composition 3) The magnetic recording medium according to configuration 2, wherein the ratio of the first exchange coupling strength to the second exchange coupling strength is 0.1 or more and 0.6 or less.

[0096] (Composition 4) A magnetic recording medium according to any one of configurations 1 to 3, wherein the ratio of the first anisotropic magnetic field of the first magnetic region to the second anisotropic magnetic field of the second magnetic region is 1.4 or more and 1.7 or less.

[0097] (Composition 5) The magnetic recording medium according to configuration 4, wherein the ratio of the third anisotropic magnetic field of the third magnetic region to the second anisotropic magnetic field is 1.4 or more and 1.7 or less.

[0098] (Composition 6) The magnetic recording medium according to configuration 5, wherein the ratio of the first anisotropic magnetic field to the third anisotropic magnetic field is 0.9 or more and 1.1 or less.

[0099] (Composition 7) A magnetic recording medium according to any one of configurations 1 to 6, further comprising a non-magnetic first intermediate region provided between the second magnetic region and the first magnetic region.

[0100] (Composition 8) A magnetic recording medium according to any one of configurations 1 to 7, wherein the first magnetic region, the second magnetic region, and the third magnetic region are granular magnetic regions.

[0101] (Composition 9) Further comprising a second intermediate magnetic region provided between the third magnetic region and the second magnetic region, The magnetic recording medium according to configuration 8, wherein the second intermediate magnetic region is a continuous magnetic region.

[0102] (Composition 10) The first magnetic region and, The second magnetic region, The third magnetic region, A first intermediate region provided between the second magnetic region and the first magnetic region, A second intermediate magnetic region is provided between the third magnetic region and the second magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Co atom concentration in the first magnetic region to the first Pt atom concentration in the first magnetic region is higher than the second composition ratio of the second Co atom concentration in the second magnetic region to the second Pt atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. The first magnetic region, the second magnetic region, and the third magnetic region are granular magnetic regions. The second intermediate magnetic region is a continuous magnetic region, The first intermediate region is a non-magnetic magnetic recording medium.

[0103] (Composition 11) Further comprising a first continuous magnetic region, The first magnetic region is provided between the third magnetic region and the first continuous magnetic region, and is a magnetic recording medium according to any one of configurations 8 to 10.

[0104] (Composition 12) The first magnetic region and, The second magnetic region, The third magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first anisotropic magnetic field in the first magnetic region is greater than the second anisotropic magnetic field in the second magnetic region. The third anisotropic magnetic field in the third magnetic region is greater than the second anisotropic magnetic field. A magnetic recording medium wherein the first distance along the first direction between the second magnetic region and the first magnetic region is longer than the second distance along the first direction between the third magnetic region and the second magnetic region, or the first magnetic region is separated from the second magnetic region and the third magnetic region is in contact with the second magnetic region.

[0105] (Composition 13) The magnetic recording medium according to configuration 12, wherein the ratio of the first anisotropic magnetic field to the second anisotropic magnetic field is 1.4 or more and 1.7 or less.

[0106] (Composition 14) The magnetic recording medium according to configuration 13, wherein the ratio of the third anisotropic magnetic field to the second anisotropic magnetic field is 1.4 or more and 1.7 or less.

[0107] (Composition 15) The magnetic recording medium according to configuration 14, wherein the ratio of the first anisotropic magnetic field to the third anisotropic magnetic field is 0.9 or more and 1.1 or less.

[0108] (Composition 16) The first anisotropic magnetic field is 19000 Oe or more. The second anisotropic magnetic field is between 11,000 Oe and 15,000 Oe. The magnetic recording medium according to any one of configurations 12 to 15, wherein the third anisotropic magnetic field is 18,000 Oe or more.

[0109] (Composition 17) Non-magnetic substrate and The middle class, Furthermore, The third magnetic region is provided between the non-magnetic substrate and the first magnetic region. The intermediate layer is provided between the non-magnetic substrate and the third magnetic region. The magnetic recording medium according to any one of configurations 1 to 16, wherein the intermediate layer is soft magnetic.

[0110] (Composition 18) A magnetic recording medium described in any one of configurations 1 to 17, Magnetic head and Equipped with, A magnetic recording device in which the first magnetic region is located between the third magnetic region and the magnetic head.

[0111] (Composition 19) The magnetic head is capable of recording, The magnetic recording apparatus according to configuration 18, wherein, in the recording operation, an alternating magnetic field is applied to the magnetic recording medium from the magnetic head, and a recording magnetic field is applied to the magnetic recording medium from the magnetic head.

[0112] (Composition 20) The magnetic head is The first magnetic pole and, The second magnetic pole and, A magnetic element provided between the first magnetic pole and the second magnetic pole, Includes, The aforementioned magnetic circuit is A first magnetic layer provided between the first magnetic pole and the second magnetic pole, A second magnetic layer is provided between the first magnetic layer and the second magnetic pole, A third magnetic layer is provided between the second magnetic layer and the second magnetic pole, A fourth magnetic layer is provided between the third magnetic layer and the second magnetic pole, A magnetic recording device according to configuration 18 or 19, including the configuration described above.

[0113] According to the embodiment, a magnetic recording medium and a magnetic recording device capable of improving recording density can be provided.

[0114] In this specification, "perpendicular" and "parallel" do not mean strictly perpendicular and strictly parallel, but also include variations in the manufacturing process, for example, and it is sufficient if they are substantially perpendicular and substantially parallel.

[0115] Embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element included in the magnetic head and magnetic recording device, such as magnetic poles, magnetic elements, magnetic layers, non-magnetic layers, and control units, is included within the scope of the present invention as long as those skilled in the art can appropriately select from the known range to implement the present invention and obtain similar effects.

[0116] Combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.

[0117] Furthermore, all magnetic recording devices that can be implemented by those skilled in the art by appropriately modifying the design based on the magnetic recording device described above as an embodiment of the present invention also fall within the scope of the present invention, insofar as they encompass the gist of the present invention.

[0118] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention.

[0119] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of symbols]

[0120] 20: Magnetic element, 21-24: 1st-4th magnetic layers, 31, 32: 1st and 2nd magnetic poles, 41-45: 1st-5th non-magnetic layers, 60: Recording section, 70: Playback section, 71: Magnetic playback element, 72a, 72b: 2nd playback magnetic shield, 80, 80A-80F: Magnetic recording medium, 80M: Magnetization, 80R, 80RA: Recording layer, 81, 81A: 1st magnetic region, 82, 82A: 2nd magnetic region, 83, 83A: 3rd magnetic region, 81f-83f: 1st-3rd magnetic film, 84, 84A: Intermediate layer, 85: Medium movement direction, 85S: Non-magnetic substrate, 91n: 1st intermediate region, 92m: 2nd intermediate magnetic region, 92n: 2nd intermediate region 95m: First continuous magnetic region, 110, 110A: Magnetic head, 150: Magnetic recording device, 154: Suspension, 155: Arm, 156: Voice coil motor, 157: Bearing section, 158: Head gimbal assembly, 159: Head slider, 159A: Air inlet side, 159B: Air outlet side, 160: Head stack assembly, 161: Support frame, 162: Coil, 180: Recording medium disk, 180M: Spindle motor, 181: Recording medium, 190: Signal processing unit, AR: Arrow, D1: First direction, d1, d2: First and second distances, ic: Current, je: Electron flow, t1~t3: First to third thickness

Claims

1. The first magnetic region and, The second magnetic region and The third magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Pt atom concentration in the first magnetic region to the first Co atom concentration in the first magnetic region is higher than the second composition ratio of the second Pt atom concentration in the second magnetic region to the second Co atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. The first distance along the first direction between the second magnetic region and the first magnetic region is longer than the second distance along the first direction between the third magnetic region and the second magnetic region, or the first magnetic region is separated from the second magnetic region and the third magnetic region is in contact with the second magnetic region. The first exchange coupling strength between the second magnetic region and the first magnetic region is lower than the second exchange coupling strength between the third magnetic region and the second magnetic region. A magnetic recording medium in which the ratio of the first exchange coupling strength to the second exchange coupling strength is 0.1 or more and 0.6 or less.

2. A first magnetic region, The second magnetic region and The third magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Pt atom concentration in the first magnetic region to the first Co atom concentration in the first magnetic region is higher than the second composition ratio of the second Pt atom concentration in the second magnetic region to the second Co atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. The first distance along the first direction between the second magnetic region and the first magnetic region is longer than the second distance along the first direction between the third magnetic region and the second magnetic region, or the first magnetic region is separated from the second magnetic region and the third magnetic region is in contact with the second magnetic region. A magnetic recording medium in which the ratio of the first anisotropic magnetic field of the first magnetic region to the second anisotropic magnetic field of the second magnetic region is 1.4 or more and 1.7 or less.

3. The magnetic recording medium according to claim 2, wherein the ratio of the third anisotropic magnetic field of the third magnetic region to the second anisotropic magnetic field is 1.4 or more and 1.7 or less.

4. The magnetic recording medium according to claim 3, wherein the ratio of the first anisotropic magnetic field to the third anisotropic magnetic field is 0.9 or more and 1.1 or less.

5. The magnetic recording medium according to claim 1, further comprising a non-magnetic first intermediate region provided between the second magnetic region and the first magnetic region.

6. The first magnetic region and, The second magnetic region and The third magnetic region, A first intermediate region provided between the second magnetic region and the first magnetic region, A second intermediate magnetic region is provided between the third magnetic region and the second magnetic region, Equipped with, The second magnetic region is located between the third magnetic region and the first magnetic region in a first direction from the third magnetic region to the first magnetic region. The first composition ratio of the first Co atom concentration in the first magnetic region to the first Pt atom concentration in the first magnetic region is higher than the second composition ratio of the second Co atom concentration in the second magnetic region to the second Pt atom concentration in the second magnetic region. The third composition ratio of the third Pt atom concentration in the third magnetic region to the third Co atom concentration in the third magnetic region is higher than the second composition ratio. The first magnetic region, the second magnetic region, and the third magnetic region are granular magnetic regions. The second intermediate magnetic region is a continuous magnetic region, The first intermediate region is a non-magnetic magnetic recording medium.

7. A magnetic recording medium according to any one of claims 1 to 6, Magnetic head and Equipped with, A magnetic recording device in which the first magnetic region is located between the third magnetic region and the magnetic head.

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