Magnetic sensor, magnetic head, and magnetic recording device

Abstract

The present invention provides a magnetic sensor, a magnetic head, and a magnetic recording device that detect a target magnetic field with high sensitivity. [Solution] The magnetic sensor 70A includes a detection unit 70x. The detection unit 70x includes first to fourth shields 41 to 44, a first magnetic member 11, and non-magnetic first to fourth conductive members 21 to 24. The direction from the third shield 41 to the fourth shield 44 intersects with the direction from the first shield 41 to the second shield 42. The first magnetic member 11 is provided between the first shield 41 and the second shield 42 and between the third shield 43 and the fourth shield 44. The first to fourth conductive members 21 to 24 are provided, respectively, between the first to fourth shields 41 to 44 and the first magnetic member 11. The first to fourth conductive members satisfy any of the first to fourth conditions relating to the first to third materials. The first material includes Nb, Mo, Tc, Ta, W, or Re. The second material includes Ru, Rh, Pd, Os, Ir, or Pt. The third material includes Cu, Al, Tb, or Cr.

Description

Technical Field

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

Background Art

[0002] Information recorded on a magnetic recording medium is reproduced using a magnetic head employing a magnetic sensor including a magnetic layer. In the magnetic sensor, improvement in characteristics is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments of the present invention provide a magnetic sensor, a magnetic head, and a magnetic recording device capable of improving characteristics.

Means for Solving the Problems

[0005] According to the embodiment, the magnetic sensor includes a detection unit. The detection unit includes a first shield, a second shield, a third shield, a fourth shield, a first magnetic member, a first conductive member, a second conductive member, a third conductive member, and a fourth conductive member. The second direction from the third shield to the fourth shield intersects the first direction from the first shield to the second shield. The first magnetic member is provided between the first shield and the second shield, and between the third shield and the fourth shield. The first magnetic member is provided between the first shield and the first magnetic member and is non-magnetic. The second conductive member is provided between the second shield and the first magnetic member and is non-magnetic. The third conductive member is provided between the third shield and the first magnetic member and is non-magnetic. The fourth conductive member is provided between the fourth shield and the first magnetic member and is non-magnetic. The first conductive member, the second conductive member, the third conductive member, and the fourth conductive member satisfy any of the first, second, third, and fourth conditions. In the first condition, one of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member includes either the first material or the second material, and the other three of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member include the third material. In the second condition, the first conductive member and the second conductive member include either the first material or the second material, and the third conductive member and the fourth conductive member include the third material. In the third condition, the third conductive member and the fourth conductive member include either the first material or the second material, and the first conductive member and the second conductive member include the third material. In the fourth condition, three of the first conductive member, second conductive member, third conductive member, and fourth conductive member include one of the first material and the second material, and the other one of the first conductive member, second conductive member, third conductive member, and fourth conductive member includes the third material. The first material includes at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material includes at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt.The third material comprises at least one selected from the group consisting of Cu, Al, Tb, and Cr. [Brief explanation of the drawing]

[0006] [Figure 1] Figures 1(a) and 1(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. [Figure 2] Figures 2(a) and 2(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. [Figure 3] Figures 3(a) and 3(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. [Figure 4] Figures 4(a) and 4(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. [Figure 5] Figure 5 is a schematic perspective view illustrating a magnetic head and magnetic recording device according to the second embodiment. [Figure 6] Figure 6 is a schematic perspective view illustrating a part of the magnetic recording apparatus according to the embodiment. [Figure 7] Figure 7 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. [Figure 8] Figures 8(a) and 8(b) are schematic perspective views illustrating a part of a magnetic recording apparatus according to an embodiment. [Modes for carrying out the invention]

[0007] The embodiments of the present invention will be described below with reference to the drawings. Drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of different parts, are not necessarily identical to those of reality. Even when representing the same part, the dimensions and ratios may be depicted differently in different drawings. In this specification and in each figure, elements similar to those described above are denoted by the same reference numerals with respect to previously shown figures, and detailed explanations are omitted as appropriate.

[0008] (First Embodiment) Figures 1(a) and 1(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. As shown in Figure 1(a), the magnetic sensor 70A according to this embodiment includes a detection unit 70x. The detection unit 70x includes a first shield 41, a second shield 42, a third shield 43, a fourth shield 44, a first magnetic member 11, a first conductive member 21, a second conductive member 22, a third conductive member 23, and a fourth conductive member 24. Figure 1(b) corresponds to a cross-sectional view in a plan including the first shield 41, the first magnetic member 11, and the second shield 42.

[0009] The second direction D2 from the third shield 43 to the fourth shield 44 intersects with the first direction D1 from the first shield 41 to the second shield 42.

[0010] The X-axis is defined as one direction perpendicular to the Z-axis. The Y-axis is defined as a direction perpendicular to both the Z-axis and X-axis. In the examples in Figures 1(a) and 1(b), the first direction D1 can be the X-axis. The second direction D2 can be the Y-axis.

[0011] The first magnetic member 11 is provided between the first shield 41 and the second shield 42, and between the third shield 43 and the fourth shield 44.

[0012] The first conductive member 21 is provided between the first shield 41 and the first magnetic member 11 and is non-magnetic. The second conductive member 22 is provided between the second shield 42 and the first magnetic member 11 and is non-magnetic. The third conductive member 23 is provided between the third shield 43 and the first magnetic member 11 and is non-magnetic. The fourth conductive member 24 is provided between the fourth shield 44 and the first magnetic member 11 and is non-magnetic.

[0013] In this embodiment, the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 satisfy any of the first, second, third, and fourth conditions.

[0014] Under the first condition, one of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 includes one of the first material and the second material. The other three of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 include the third material.

[0015] The first material includes at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material includes at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt. The third material includes at least one selected from the group consisting of Cu, Al, Tb, and Cr.

[0016] Under the second condition, the first conductive member 21 and the second conductive member 22 include one of the above-mentioned first material and the second material, and the third conductive member 23 and the fourth conductive member 24 include the above-mentioned third material.

[0017] Under the third condition, the third conductive member 23 and the fourth conductive member 24 include one of the above-mentioned first material and the second material, and the first conductive member 21 and the second conductive member 22 include the above-mentioned third material.

[0018] Under the fourth condition, three of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 include one of the above-mentioned first material and the second material, and the other one of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 includes the third material.

[0019] In the detection unit 70x as described above, for example, a first current i1 flows through the first magnetic member 11 via the first shield 41 and the second shield 42. In this state, when a detection target magnetic field is applied to the detection unit 70x, the signal (voltage Vx) generated in the laminated structure of the third shield 43, the first magnetic member 11, and the fourth shield 44 changes according to the detection target magnetic field. By detecting the signal (voltage Vx), the detection target magnetic field can be detected. As will be described later, the first current i1 may flow through the first magnetic member 11 via the third shield 43 and the fourth shield 44, and the signal (voltage Vx) generated in the laminated structure of the first shield 41, the first magnetic member 11, and the second shield 42 may be detected.

[0020] As described above, in the embodiment, the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 satisfy any one of the above first to fourth conditions. Under such conditions, it has been found that a large signal (voltage Vx) can be obtained. By applying such materials, the detection target magnetic field can be detected with high sensitivity. The detection target magnetic field can be detected with high accuracy. A magnetic sensor capable of improving characteristics can be provided.

[0021] For example, in the above first material, a negative spin Hall angle with a large absolute value can be obtained. For example, in the above second material, a positive spin Hall angle with a large absolute value can be obtained. It is considered that a large signal (voltage Vx) is obtained by the action of the spins accumulated in the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 and the magnetization of the first magnetic member 11 due to the large spin Hall angle.

[0022] By selecting and applying one of the first material and the second material, the signals generated between the first conductive member 21 and the first magnetic member 11, between the second conductive member 22 and the first magnetic member 11, between the third conductive member 23 and the first magnetic member 11, and between the fourth conductive member 24 and the first magnetic member 11 are coordinated, and a large signal (voltage Vx) is obtained.

[0023] In the third material, the spin Hall angle is small. Even when this third material is combined with either the first or second material, the decrease in the absolute value of the spin Hall angle is suppressed. Overall, a large spin Hall angle is maintained.

[0024] Under the above conditions 1 to 4, a large signal (voltage Vx) can be obtained.

[0025] In this embodiment, the first magnetic member 11 may include at least one selected from the group consisting of Fe, Co, and Ni. In such a material, good crystallinity is easily obtained, which makes it easier to obtain stable properties. On the other hand, in such a material, the signal (voltage Vx) obtained when the first current i1 flows is relatively small. By combining the first magnetic member 11 containing such a material with the conductive member (first material or second material) described above, a large signal (voltage Vx) can be easily and stably obtained.

[0026] When the first magnetic member 11 contains at least one selected from the group consisting of Fe, Co, and Ni, the first magnetic member 11 may further contain B. For example, the first magnetic member 11 contains CoFeB. This makes it easier to obtain an even better crystal orientation.

[0027] In this embodiment, the first magnetic member 11 may exhibit an anomalous Hall effect, making it easier to obtain a large signal (voltage Vx).

[0028] In embodiments, the first magnetic member 11 may include at least one selected from the group consisting of Co2MnGa, Co2MnAl, FePt, MnGa, Mn3Sn, Mn3Ge, Mn3Ga, RuO2, MnTe, CrSb, and Mn5Si3. These materials can effectively provide, for example, an anomalous Hall effect.

[0029] As shown in Figure 1(b), the first shield 41 includes a first end face 41F. The direction from the first magnetic member 11 to the fifth conductive member 25 is along a third direction D3. The third direction D3 intersects a plane containing the first direction D1 and the second direction D2. The third direction D3 is, for example, the Z-axis direction. When the magnetic sensor 70A is applied to a magnetic head, the first end face 41F may correspond to the media-facing surface.

[0030] As shown in Figure 1(b), the detection unit 70x may further include a non-magnetic fifth conductive member 25. The position of at least a portion of the first magnetic member 11 in the third direction D3 (first position) lies between the position of the first end face 41F in the third direction D3 (first end face position) and the position of the fifth conductive member 25 in the third direction D3 (fifth conductive member position).

[0031] For example, the fifth conductive member 25 may contain either the first material or the second material. A portion of the current passing through the first magnetic member 11 may flow through the fifth conductive member 25. By including the above material in the fifth conductive member 25, spin accumulation is more easily maintained. A large signal (voltage Vx) is obtained through the interaction of the spins accumulated in the fifth conductive member 25 and the magnetization of the first magnetic member 11.

[0032] In the example shown in Figure 1(a), the third shield 43 is provided between a part of the first shield 41 and a part of the second shield 42 in the first direction D1. The fourth shield 44 is provided between another part of the first shield 41 and another part of the second shield 42 in the first direction D1.

[0033] As shown in Figure 1(a), the length of the first conductive member 21 along the first direction D1 is defined as the first conductive member length L1. The first conductive member length L1 is preferably 4 nm or more. This prevents spins accumulating in opposite directions at the end face from mixing, making accumulation easier. As a result, the amount of spin accumulation increases, and a large signal (voltage Vx) can be obtained.

[0034] As shown in Figure 1(a), the length of the second conductive member 22 along the first direction D1 is defined as the second conductive member length L2. The second conductive member length L2 is preferably 4 nm or more. This prevents spins accumulating in opposite directions at the end face from mixing, making accumulation easier. As a result, the amount of spin accumulation increases, and a large signal (voltage Vx) can be obtained.

[0035] As shown in Figure 1(a), the length of the third conductive member 23 along the first direction D1 is defined as the length of the third conductive member L3. The length of the third conductive member L3 is preferably 4 nm or more. This prevents the mixing of spins accumulating in opposite directions at the end face, making accumulation easier. This increases the amount of spin accumulation, resulting in a larger signal (voltage Vx).

[0036] As shown in Figure 1(a), the length of the fourth conductive member 24 along the first direction D1 is defined as the length of the fourth conductive member L4. The length of the fourth conductive member L4 is preferably 4 nm or more. This prevents spins accumulating in opposite directions at the end face from mixing, making accumulation easier. As a result, the amount of spin accumulation increases, and a large signal (voltage Vx) can be obtained.

[0037] As shown in Figure 1(a), in this example, the first shield magnetization 41M of the first shield 41 has an orientation from the third shield 43 to the fourth shield 44. The second shield magnetization 42M of the second shield 42 has an orientation from the third shield 43 to the fourth shield 44. The third shield magnetization 43M of the third shield 43 has an orientation from the third shield 43 to the fourth shield 44. The fourth shield magnetization 44M of the fourth shield 44 has an orientation from the third shield 43 to the fourth shield 44. The first magnetic member magnetization 11M of the first magnetic member 11 has an orientation from the third shield 43 to the fourth shield 44.

[0038] The detection unit 70x may further include an insulating member 31. For example, the insulating member 31 may include a first insulating part 31a, a second insulating part 31b, a third insulating part 31c, and a fourth insulating part 31d. The first insulating part 31a is provided between a part of the first shield 41 and the third shield 43. The second insulating part 31b is provided between another part of the first shield 41 and the fourth shield 44. The third insulating part 31c is provided between a part of the second shield 42 and the third shield 43. The fourth insulating part 31d is provided between another part of the second shield 42 and the fourth shield 44.

[0039] As shown in Figure 1(a), a portion of the insulating member 31 may be provided between the first shield 41 and the second shield 42.

[0040] As shown in Figure 1(a), the detection unit 70x may include a first terminal 51, a second terminal 52, a third terminal 53, and a fourth terminal 54. The first terminal 51 is electrically connected to the first shield 41. The second terminal 52 is electrically connected to the second shield 42. The third terminal 53 is electrically connected to the third shield 43. The fourth terminal 54 is electrically connected to the fourth shield 44.

[0041] For example, a voltage detection circuit 75v may be connected between the first terminal 51 and the second terminal 52. A current supply circuit 75i may be connected between the third terminal 53 and the fourth terminal 54. The current supply circuit 75i is configured to supply a first current i1 through the current path including the third shield 43, the first magnetic member 11, and the fourth shield 44 via the third terminal 53 and the fourth terminal 54. The voltage detection circuit 75v is configured to detect an electrical signal (voltage Vx) generated between the first terminal 51 and the second terminal 52.

[0042] Thus, the detection unit 70x may be configured such that the voltage Vx between the first terminal 51 and the second terminal 52 changes according to the magnetic field to be detected when a first current i1 flows between the third terminal 53 and the fourth terminal 54.

[0043] Figures 2(a) and 2(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. As shown in Figure 2(a), in the magnetic sensor 70B according to this embodiment, a voltage detection circuit 75v is connected between the third terminal 53 and the fourth terminal 54, and a current supply circuit 75i is connected between the first terminal 51 and the second terminal 52. The configuration of the magnetic sensor 70B, apart from these, may be the same as that of the magnetic sensor 70A.

[0044] In the magnetic sensor 70B, a large signal (voltage Vx) can be obtained by applying either the first or second material described above. The first to fourth configurations may also be applied to the magnetic sensor 70B.

[0045] In the magnetic sensor 70B, the detection unit 70x may be configured such that the voltage Vx between the third terminal 53 and the fourth terminal 54 changes according to the magnetic field to be detected when a first current i1 flows between the first terminal 51 and the second terminal 52.

[0046] Figures 3(a) and 3(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. As shown in Figure 3(a), the configuration of the multiple shields in the magnetic sensor 70C according to this embodiment is different from that of the magnetic sensor 70A. The configuration of the magnetic sensor 70C, excluding this, may be the same as that of the magnetic sensor 70A.

[0047] In the magnetic sensor 70C, the first shield 41 is provided between a part of the third shield 43 and a part of the fourth shield 44 in the first direction D1. The second shield 42 is provided between another part of the third shield 43 and another part of the fourth shield 44 in the first direction D1.

[0048] In this example, the first direction D1 may be along the Y-axis. The second direction D2 may be along the X-axis.

[0049] In the magnetic sensor 70C, a large signal (voltage Vx) can be obtained by applying either the first or second material described above. The first to fourth configurations may also be applied to the magnetic sensor 70C.

[0050] In the magnetic sensor 70C, a voltage detection circuit 75V is connected between the first terminal 51 and the second terminal 52, and a current supply circuit 75i is connected between the third terminal 53 and the fourth terminal 54.

[0051] In the configuration of the magnetic sensor 70C, the length of the third conductive member 23 along the second direction D2 is defined as the length L3 of the third conductive member. The length L3 of the third conductive member is preferably 4 nm or more. This prevents the mixing of spins accumulating in opposite directions at the end face, making accumulation easier. This increases the amount of spin accumulation, resulting in a larger signal (voltage Vx).

[0052] In the configuration of the magnetic sensor 70C, the length of the fourth conductive member 24 along the second direction D2 is defined as the length of the fourth conductive member L4. The length of the fourth conductive member L4 is preferably 4 nm or more. This prevents the mixing of spins accumulating in opposite directions at the end face, making accumulation easier. This increases the amount of spin accumulation, resulting in a larger signal (voltage Vx).

[0053] In the configuration of the magnetic sensor 70C, the length of the first conductive member 21 along the second direction D2 is defined as the first conductive member length L1. The first conductive member length L1 is preferably 4 nm or more. This prevents spins accumulating in opposite directions at the end face from mixing, making accumulation easier. As a result, the amount of spin accumulation increases, and a larger signal (voltage Vx) can be obtained.

[0054] In the configuration of the magnetic sensor 70C, the length of the second conductive member 22 along the second direction D2 is defined as the second conductive member length L2. The second conductive member length L2 is preferably 4 nm or more. This prevents spins accumulating in opposite directions at the end face from mixing, making accumulation easier. This increases the amount of spin accumulation, resulting in a larger signal (voltage Vx).

[0055] As shown in Figure 3(a), in the magnetic sensor 70C, the insulating member 31 may include a first insulating portion 31a, a second insulating portion 31b, a third insulating portion 31c, and a fourth insulating portion 31d. The first insulating portion 31a is provided between the third shield 43 and a part of the first shield 41. The second insulating portion 31b is provided between another part of the third shield 43 and the second shield 42. The third insulating portion 31c is provided between a part of the fourth shield 44 and the first shield 41. The fourth insulating portion 31d is provided between another part of the fourth shield 44 and the second shield 42.

[0056] The insulating member 31 may include a fifth insulating portion 31e, a sixth insulating portion 31f, a seventh insulating portion 31g, and an eighth insulating portion 31h. The fifth insulating portion 31e is provided between a part of the first shield 41 and the first magnetic member 11. The sixth insulating portion 31f is provided between another part of the first shield 41 and the first magnetic member 11. The seventh insulating portion 31g is provided between a part of the second shield 42 and the first magnetic member 11. The eighth insulating portion 31h is provided between another part of the second shield 42 and the first magnetic member 11.

[0057] The first conductive member 21 may be provided between the fifth insulating portion 31e and the sixth insulating portion 31f. The second conductive member 22 may be provided between the seventh insulating portion 31g and the eighth insulating portion 31h.

[0058] Figures 4(a) and 4(b) are schematic cross-sectional views illustrating a magnetic sensor according to the first embodiment. As shown in Figure 4(a), in the magnetic sensor 70D according to this embodiment, a voltage detection circuit 75v is connected between the third terminal 53 and the fourth terminal 54, and a current supply circuit 75i is connected between the first terminal 51 and the second terminal 52. The configuration of the magnetic sensor 70D, aside from these, may be the same as that of the magnetic sensor 70C.

[0059] In the magnetic sensor 70D, a large signal (voltage Vx) can be obtained by applying either the first or second material described above. The first to fourth configurations may also be applied to the magnetic sensor 70D.

[0060] In the magnetic sensor 70D, the detection unit 70x may be configured such that the voltage Vx between the third terminal 53 and the fourth terminal 54 changes according to the magnetic field to be detected when a first current i1 flows between the first terminal 51 and the second terminal 52.

[0061] In an embodiment, if the detection unit 70x includes a first conductive member 21, a second conductive member 22, a third conductive member 23, a fourth conductive member 24, and a fifth conductive member 25, the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 may not satisfy any of the first to fourth conditions described above. In this case, the fifth conductive member 25 includes either a first material or a second material. The first material includes at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material includes at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt.

[0062] In the embodiment, at least one of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 may contain Bi. This results in a large absolute value spin Hall angle. A large signal (voltage Vx) is obtained. In Bi, the spin Hall angle may be positive or negative. At least one of the first conductive member 21, the second conductive member 22, the third conductive member 23, and the fourth conductive member 24 may further contain Sb in addition to Bi. At least one of these conductive members may contain a compound containing Bi and Sb. A large spin Hall angle is obtained.

[0063] (Second Embodiment) Figure 5 is a schematic perspective view illustrating a magnetic head and magnetic recording device according to the second embodiment. As shown in Figure 5, the magnetic head 110 according to this embodiment includes a playback unit 70. The playback unit 70 includes a magnetic sensor (magnetic sensor 70A, magnetic sensor 70B, magnetic sensor 70C, or magnetic sensor 70D) according to the first embodiment. The magnetic head 110 is used together with a magnetic recording medium 80. In this example, the magnetic head 110 includes a recording unit 90. The recording unit 90 of the magnetic head 110 records information on the magnetic recording medium 80. The playback unit 70 plays back the information recorded on the magnetic recording medium 80.

[0064] The magnetic recording medium 80 includes, for example, a media substrate 82 and a magnetic recording layer 81 provided on the media substrate 82. The magnetization 83 of the magnetic recording layer 81 is controlled by the recording unit 90. The recording unit 90 includes, for example, a first magnetic pole 91 and a second magnetic pole 92. The first magnetic pole 91 is, for example, a main magnetic pole. The second magnetic pole 92 is, for example, a trailing shield. The recording unit 90 may also include a recording unit element 93. The recording unit element 93 may include a magnetic field control element or a high-frequency oscillation element, etc. The recording unit element 93 may be omitted.

[0065] 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 83 of the magnetic recording layer 81.

[0066] In the magnetic head 110, if a magnetic sensor 70A or magnetic sensor 70B is applied, the first regenerative magnetic shield 72a corresponds to, for example, one of the first shield 41 and the second shield 42, and the second regenerative magnetic shield 72b corresponds to, for example, the other of the first shield 41 and the second shield 42.

[0067] In the magnetic head 110, if a magnetic sensor 70C or magnetic sensor 70D is applied, the first regenerative magnetic shield 72a corresponds to, for example, one of the third shield 43 and the fourth shield 44, and the second regenerative magnetic shield 72b corresponds to, for example, the other of the third shield 43 and the fourth shield 44. The magnetic regeneration element 71 includes the first magnetic member 11.

[0068] As shown in Figure 5, 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 83 of the magnetic recording layer 81 at any position. The magnetic head 110 reproduces the information corresponding to the magnetization 83 of the magnetic recording layer 81 at any position. The magnetic field to be detected described in relation to the first embodiment is based on the magnetization 83 of the magnetic recording medium 80.

[0069] Figure 6 is a schematic perspective view illustrating a part of the magnetic recording apparatus according to the embodiment. Figure 6 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.

[0070] 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.

[0071] Figure 7 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. The magnetic recording device may be a magnetic recording and playback device. As shown in Figure 7, 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).

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] Figures 8(a) and 8(b) are schematic perspective views illustrating a part of a magnetic recording apparatus according to an embodiment. Figure 8(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 8(b) is a perspective view illustrating a magnetic head assembly (head gimbal assembly: HGA) 158, which is part of the head stack assembly 160.

[0077] As shown in Figure 8(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.

[0078] As shown in Figure 8(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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] The embodiments may include the following technical proposals. (Technical proposal 1) The first shield and, The second shield, The third shield and, The fourth shield is such that the second direction from the third shield to the fourth shield intersects with the first direction from the first shield to the second shield, and the fourth shield is... A first magnetic member provided between the first shield and the second shield, and between the third shield and the fourth shield, A non-magnetic first conductive member is provided between the first shield and the first magnetic member, A non-magnetic second conductive member is provided between the second shield and the first magnetic member, A non-magnetic third conductive member is provided between the third shield and the first magnetic member, A non-magnetic fourth conductive member is provided between the fourth shield and the first magnetic member, It includes a detection unit, The first conductive member, the second conductive member, the third conductive member, and the fourth conductive member satisfy any of the first, second, third, and fourth conditions, In the first condition, one of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member includes one of the first material and the second material, and the other three of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member include the third material. In the second condition, the first conductive member and the second conductive member include one of the first material and the second material, and the third conductive member and the fourth conductive member include the third material. In the third condition, the third conductive member and the fourth conductive member include one of the first material and the second material, and the first conductive member and the second conductive member include the third material. In the fourth condition, three of the first conductive member, second conductive member, third conductive member and fourth conductive member include one of the first material and the second material, and the other one of the first conductive member, second conductive member, third conductive member and fourth conductive member includes the third material. The first material comprises at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material comprises at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt. The third material comprises at least one selected from the group consisting of Cu, Al, Tb, and Cr, in a magnetic sensor.

[0086] (Technical proposal 2) The magnetic sensor according to Technical Proposal 1, wherein the first magnetic member includes at least one selected from the group consisting of Fe, Co, and Ni.

[0087] (Technical proposal 3) The magnetic sensor according to Technical Proposal 2, wherein the first magnetic member further includes B.

[0088] (Technical proposal 4) The magnetic sensor according to Technical Proposal 1, wherein the first magnetic member includes at least one selected from the group consisting of Co2MnGa, Co2MnAl, FePt, MnGa, Mn3Sn, Mn3Ge, Mn3Ga, RuO2, MnTe, CrSb, and Mn5Si3.

[0089] (Technical proposal 5) The first magnetic member is a magnetic sensor according to Technical Proposal 4, having an anomalous Hall effect.

[0090] (Technical proposal 6) The detection unit further includes a non-magnetic fifth conductive member, The first shield includes a first end face, The direction from the first magnetic member to the fifth conductive member is along a third direction that intersects a plane including the first and second directions. A magnetic sensor according to any one of Technical Proposals 1 to 5, wherein the first position in the third direction of at least a portion of the first magnetic member is located between the first end face position in the third direction of the first end face and the fifth conductive member position in the third direction of the fifth conductive member.

[0091] (Technical proposal 7) The magnetic sensor according to Technical Proposal 6, wherein the fifth conductive member includes one of the first material and the second material.

[0092] (Technical proposal 8) The first shield and, The second shield, The third shield and, The fourth shield is such that the second direction from the third shield to the fourth shield intersects with the first direction from the first shield to the second shield, and the fourth shield is... A first magnetic member provided between the first shield and the second shield, and between the third shield and the fourth shield, A non-magnetic first conductive member is provided between the first shield and the first magnetic member, A non-magnetic second conductive member is provided between the second shield and the first magnetic member, A non-magnetic third conductive member is provided between the third shield and the first magnetic member, A non-magnetic fourth conductive member is provided between the fourth shield and the first magnetic member, A non-magnetic fifth conductive member, It includes a detection unit, The first shield includes a first end face, The direction from the first magnetic member to the fifth conductive member is along a third direction that intersects a plane including the first and second directions. A magnetic sensor wherein the first position in the third direction of at least a portion of the first magnetic member is located between the first end face position in the third direction of the first end face and the fifth conductive member position in the third direction of the fifth conductive member.

[0093] (Technical proposal 9) The fifth conductive member includes one of the first material and the second material, The first material comprises at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The magnetic sensor according to Technical Proposal 8, wherein the second material comprises at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt.

[0094] (Technical proposal 10) The first shield and, The second shield, The third shield and, The fourth shield is such that the second direction from the third shield to the fourth shield intersects with the first direction from the first shield to the second shield, and the fourth shield is... A first magnetic member provided between the first shield and the second shield, and between the third shield and the fourth shield, A non-magnetic first conductive member is provided between the first shield and the first magnetic member, A non-magnetic second conductive member is provided between the second shield and the first magnetic member, A non-magnetic third conductive member is provided between the third shield and the first magnetic member, A non-magnetic fourth conductive member is provided between the fourth shield and the first magnetic member, It includes a detection unit, The first magnetic member comprises at least one selected from the group consisting of Fe, Co, and Ni. The first conductive member, the second conductive member, the third conductive member, and the fourth conductive member each include one of the first material and the second material. The first material comprises at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material comprises at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt, and is used in the magnetic sensor.

[0095] (Technical proposal 11) The magnetic sensor according to technical proposal 10, wherein the first magnetic member further comprises B.

[0096] (Technical proposal 12) The third shield is provided between a part of the first shield and a part of the second shield in the first direction. The magnetic sensor according to any one of the technical proposals 1 to 11, wherein the fourth shield is provided between another part of the first shield and another part of the second shield in the first direction.

[0097] (Technical proposal 13) The magnetic sensor according to Technical Proposal 12, wherein the length of the first conductive member along the first direction of the first conductive member is 4 nm or more.

[0098] (Technical proposal 14) The first shield is provided between a part of the third shield and a part of the fourth shield in the first direction. The magnetic sensor according to any one of the technical proposals 1 to 11, wherein the second shield is provided between another part of the third shield and another part of the fourth shield in the first direction.

[0099] (Technical proposal 15) The magnetic sensor according to Technical Proposal 14, wherein the length of the third conductive member along the first direction is 4 nm or more.

[0100] (Technical proposal 16) The first shield and the first terminal electrically connected, The second terminal is electrically connected to the second shield, The third terminal is electrically connected to the third shield, The fourth terminal is electrically connected to the fourth shield, A magnetic sensor described in any one of Technical Proposals 1 to 15, further equipped with the above.

[0101] (Technical proposal 17) The magnetic sensor according to Technical Proposal 16, wherein the detection unit is configured such that the voltage between the first terminal and the second terminal changes according to the magnetic field to be detected when a first current flows between the third terminal and the fourth terminal.

[0102] (Technical proposal 18) The detection unit is configured such that the voltage between the third terminal and the fourth terminal changes according to the magnetic field to be detected when a first current flows between the first terminal and the second terminal, as described in Technical Proposal 16.

[0103] (Technical proposal 19) Equipped with a magnetic sensor as described in Technical Proposal 17 or 18, The magnetic field to be detected is a magnetic head based on the magnetization of the magnetic recording medium.

[0104] (Technical proposal 20) The magnetic head described in Technical Proposal 19, The magnetic recording medium and, A magnetic recording device equipped with a magnetic recording device.

[0105] According to the embodiment, a magnetic sensor, a magnetic head, and a magnetic recording device capable of improving characteristics can be provided.

[0106] 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.

[0107] 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 configurations of elements such as shields, magnetic members, conductive members, and terminals included in magnetic sensors, magnetic heads, and magnetic recording devices are included within the scope of the present invention as long as the present invention can be implemented in the same manner and similar effects can be obtained by appropriately selecting from the range known to those skilled in the art.

[0108] 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.

[0109] Furthermore, all magnetic sensors, magnetic heads, and magnetic recording devices that a person skilled in the art can design and implement based on the above-described embodiments of the present invention are also within the scope of the present invention, insofar as they encompass the gist of the present invention.

[0110] 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.

[0111] 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]

[0112] 11: First magnetic member, 11M: Magnetization of the first magnetic member, 21~25: First to fifth conductive members, 31: Insulating member, 31a~31h: First to eighth insulating parts, 41~44: First to fourth shields, 41F: First end face, 41M~44M: First to fourth shield magnetization, 51~54: First to fourth terminals, 70: Regeneration section, 70A~70D: Magnetic sensor, 70x: Detection section, 71: Magnetic regeneration element, 72a, 72b: First and second regeneration magnetic shields, 75i: Current supply circuit, 75v: Voltage detection circuit, 80: Magnetic recording medium, 81: Magnetic recording layer, 82: Medium substrate, 83: Magnetization, 85: Medium movement direction, 90: Recording section, 91, 92: First and second magnetic poles, 93: Recording element, 110: 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 section, AR: Arrow, D1~D3: 1st~3rd direction, L1~L4: 1st~4th conductive member length, Vx: Voltage, i1: 1st current

Claims

1. The first shield and, The second shield and, The third shield and, A fourth shield, wherein the second direction from the third shield to the fourth shield intersects with the first direction from the first shield to the second shield, and the fourth shield A first magnetic member provided between the first shield and the second shield, and between the third shield and the fourth shield, A non-magnetic first conductive member is provided between the first shield and the first magnetic member, A non-magnetic second conductive member is provided between the second shield and the first magnetic member, A non-magnetic third conductive member is provided between the third shield and the first magnetic member, A non-magnetic fourth conductive member is provided between the fourth shield and the first magnetic member, It includes a detection unit, The first conductive member, the second conductive member, the third conductive member, and the fourth conductive member satisfy any of the first, second, third, and fourth conditions, In the first condition, one of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member includes one of the first material and the second material, and the other three of the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member include the third material. In the second condition, the first conductive member and the second conductive member include one of the first material and the second material, and the third conductive member and the fourth conductive member include the third material. In the third condition, the third conductive member and the fourth conductive member include one of the first material and the second material, and the first conductive member and the second conductive member include the third material. In the fourth condition, three of the first conductive member, the second conductive member, the third conductive member and the fourth conductive member include one of the first material and the second material, and the other one of the first conductive member, the second conductive member, the third conductive member and the fourth conductive member includes the third material. The first material comprises at least one selected from the group consisting of Nb, Mo, Tc, Ta, W, and Re. The second material comprises at least one selected from the group consisting of Ru, Rh, Pd, Os, Ir, and Pt. The third material is a magnetic sensor comprising at least one selected from the group consisting of Cu, Al, Tb, and Cr.

2. The magnetic sensor according to claim 1, wherein the first magnetic member comprises at least one selected from the group consisting of Fe, Co, and Ni.

3. The magnetic sensor according to claim 2, wherein the first magnetic member further comprises B.

4. The detection unit further includes a non-magnetic fifth conductive member. The first shield includes a first end face, The direction from the first magnetic member to the fifth conductive member is along a third direction that intersects a plane including the first and second directions. The magnetic sensor according to claim 1, wherein the first position in the third direction of at least a portion of the first magnetic member is located between the first end face position in the third direction of the first end face and the fifth conductive member position in the third direction of the fifth conductive member.

5. The magnetic sensor according to claim 4, wherein the fifth conductive member includes one of the first material and the second material.

6. The first terminal is electrically connected to the first shield, The second terminal is electrically connected to the second shield, The third shield and the third terminal electrically connected, The fourth terminal electrically connected to the fourth shield, A magnetic sensor according to any one of claims 1 to 5, further comprising the above.

7. The magnetic sensor according to claim 6, wherein the detection unit is configured such that the voltage between the first terminal and the second terminal changes in accordance with the magnetic field to be detected when a first current flows between the third terminal and the fourth terminal.

8. The magnetic sensor according to claim 6, wherein the detection unit is configured such that the voltage between the third terminal and the fourth terminal changes in accordance with the magnetic field to be detected when a first current flows between the first terminal and the second terminal.

9. The magnetic sensor described in claim 7 is provided, The magnetic field to be detected is a magnetic head based on the magnetization of the magnetic recording medium.

10. The magnetic head according to claim 9, The magnetic recording medium and, A magnetic recording device equipped with a magnetic recording device.

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