阅读说明：本技术 磁头及磁记录再现装置
(Magnetic head and magnetic recording/reproducing apparatus
) 是由 首藤浩文
成田直幸
永泽鹤美
高岸雅幸
前田知幸 于 2019-03-08 设计创作，主要内容包括：提供一种能够提高记录密度的磁头和磁记录再现装置。根据实施方式,磁头包括磁极、第1屏蔽件、磁性层、第1导电层以及第2导电层。所述磁性层设置于所述磁极与所述第1屏蔽件之间。所述第1导电层设置于所述磁极与所述第1屏蔽件之间且包括选自Cu、Ag、Au、Al以及Cr中的至少一个。从所述第1导电层向所述磁性层的方向与从所述磁极向所述第1屏蔽件的第1方向交叉。所述第2导电层设置于所述第1导电层与第1屏蔽件之间的第1位置、和所述磁极与所述第1导电层之间的第2位置中的任一个。所述第2导电层包括选自Ta、Pt、W、Ru、Mo、Ir、Rh以及Pd中的至少一个。(A magnetic head and a magnetic recording/reproducing apparatus capable of improving the recording density are provided. According to an embodiment, a magnetic head includes a magnetic pole, a 1 st shield, a magnetic layer, a 1 st conductive layer, and a 2 nd conductive layer. The magnetic layer is disposed between the magnetic pole and the 1 st shield. The 1 st conductive layer is disposed between the magnetic pole and the 1 st shield and includes at least one selected from Cu, Ag, Au, Al, and Cr. The direction from the 1 st conductive layer to the magnetic layer crosses the 1 st direction from the magnetic pole to the 1 st shield. The 2 nd conductive layer is disposed at any one of a 1 st position between the 1 st conductive layer and the 1 st shield, and a 2 nd position between the magnetic pole and the 1 st conductive layer. The 2 nd conductive layer includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.)
1. A magnetic head includes:
a magnetic pole;
1 st shield;
a magnetic layer disposed between the magnetic pole and the 1 st shield;
a 1 st conductive layer disposed between the magnetic pole and the 1 st shield and including at least one selected from Cu, Ag, Au, Al, and Cr, a direction from the 1 st conductive layer to the magnetic layer crossing a 1 st direction from the magnetic pole to the 1 st shield; and
and a 2 nd conductive layer disposed at any one of a 1 st position between the 1 st conductive layer and the 1 st shield and a 2 nd position between the magnetic pole and the 1 st conductive layer and including at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.
2. The magnetic head as claimed in claim 1,
current flows from the 1 st conductive layer to the 2 nd conductive layer.
3. The magnetic head according to claim 1, further comprising:
a 3 rd conductive layer which is a non-magnetic conductive layer provided between the magnetic pole and the magnetic layer; and
a 4 th conductive layer which is a non-magnetic conductive layer provided between the magnetic layer and the 1 st shield,
the 2 nd conductive layer is disposed at the 1 st position,
the 3 rd conductive layer includes at least one selected from Cu, Ag, Au, Al and Cr,
the 4 th conductive layer includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.
4. A magnetic head as claimed in claim 3,
the 3 rd conductive layer interfaces with the magnetic pole and the magnetic layer,
the 4 th conductive layer interfaces with the magnetic layer and the 1 st shield.
5. A magnetic head as claimed in claim 3,
and a first insulating layer (1) is further provided,
the 1 st conductive layer includes a 1 st portion and a 2 nd portion,
the 1 st insulating layer is disposed between the magnetic pole and the 2 nd portion,
the 1 st portion is disposed between the 1 st insulating layer and the 3 rd conductive layer in a direction crossing the 1 st direction.
6. A magnetic head as claimed in claim 3,
and a second insulating layer (2) formed on the second insulating layer,
the 2 nd conductive layer includes a 3 rd portion and a 4 th portion,
the 2 nd insulating layer is disposed between the 1 st shield and the 4 th portion,
the 3 rd portion is disposed between the 2 nd insulating layer and the 4 th conductive layer in the direction crossing the 1 st direction.
7. The magnetic head according to claim 1, further comprising:
a 3 rd conductive layer which is a non-magnetic conductive layer disposed between the magnetic layer and the 1 st shield; and
a 4 th conductive layer which is a non-magnetic conductive layer provided between the magnetic pole and the magnetic layer,
the 2 nd conductive layer is disposed at the 2 nd position,
the 3 rd conductive layer includes at least one selected from Cu, Ag, Au, Al and Cr,
the 4 th conductive layer includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.
8. A magnetic head as claimed in claim 7,
the 3 rd conductive layer interfaces with the magnetic layer and the 1 st shield,
the 4 th conductive layer is contiguous with the magnetic pole and the magnetic layer.
9. A magnetic head as claimed in claim 7,
and a first insulating layer (1) is further provided,
the 1 st conductive layer includes a 1 st portion and a 2 nd portion,
the 1 st insulating layer is disposed between the 1 st shield and the 2 nd portion,
the 1 st portion is disposed between the 1 st insulating layer and the 3 rd conductive layer in a direction crossing the 1 st direction.
10. A magnetic recording/reproducing apparatus includes:
the magnetic head of claim 1;
a magnetic recording medium through which information is recorded; and
and a 1 st circuit capable of supplying a current between the magnetic pole and the 1 st shield.
Technical Field
Embodiments of the present invention relate to a magnetic head and a magnetic recording and reproducing apparatus.
Background
Information is recorded on a magnetic storage medium such as an HDD (Hard Disk Drive) using a magnetic head. In a magnetic head and a magnetic recording/reproducing apparatus, it is desired to increase the recording density.
Disclosure of Invention
Embodiments of the present invention provide a magnetic head and a magnetic recording and reproducing apparatus capable of improving recording density.
According to an embodiment of the present invention, a magnetic head includes a magnetic pole, a 1 st shield, a magnetic layer, a 1 st conductive layer, and a 2 nd conductive layer. The magnetic layer is disposed between the magnetic pole and the 1 st shield. The 1 st conductive layer is disposed between the magnetic pole and the 1 st shield and includes at least one selected from Cu, Ag, Au, Al, and Cr. The direction from the 1 st conductive layer to the magnetic layer crosses the 1 st direction from the magnetic pole to the 1 st shield. The 2 nd conductive layer is disposed at any one of a 1 st position between the 1 st conductive layer and the 1 st shield, and a 2 nd position between the magnetic pole and the 1 st conductive layer. The 2 nd conductive layer includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd.
According to the magnetic head having the above configuration, a magnetic head and a magnetic recording and reproducing apparatus capable of improving recording density can be provided.
Drawings
Fig. 1(a) and 1(b) are schematic cross-sectional views illustrating a magnetic head of embodiment 1.
Fig. 2 is a schematic cross-sectional view illustrating the operation of the magnetic head according to embodiment 1.
Fig. 3 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
Fig. 4(a) and 4(b) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
Fig. 5 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
Fig. 6 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
Fig. 7(a) to 7(c) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
Fig. 8(a) to 8(c) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
Fig. 9(a) to 9(d) are schematic plan views illustrating the magnetic head of embodiment 1.
Fig. 10(a) and 10(b) are schematic diagrams illustrating an operation of the magnetic head according to the embodiment.
Fig. 11 is a schematic perspective view illustrating a part of the magnetic recording and reproducing apparatus of the embodiment.
Fig. 12 is a schematic perspective view illustrating a magnetic recording and reproducing apparatus of the embodiment.
Fig. 13(a) and 13(b) are schematic perspective views illustrating a part of the magnetic recording and reproducing device of the embodiment.
Description of the reference symbols
20D: 1 st circuit, 21-24: 1 st to 4 th conductive layers, 23sp and 24 sp: spin torque, 25: magnetic layer, 25M: magnetization, 25 a: face 1, 25 s: side surface, 30: magnetic pole, 30D: circuit 2, 30F: pole face, 30M: magnetization, 30 c: coil, 30 e: end, 30 i: insulation, 30sp, 31 sp: spin torque, 31: 1 st shield, 31M: magnetization, 32: 2 nd shield, 41, 42: 1 st and 2 nd insulating layers, 80: magnetic recording medium, 80 c: center, 85: medium moving direction, 110a, 111a, 120, 121, 130a, 130b, 131a, 131b, 140 to 143: magnetic head, 150: magnetic recording and reproducing apparatus, 154: suspension, 155: arm, 156: voice coil motor, 157: bearing portion, 158: head gimbal assembly, 159: head slider, 159A: air inflow side, 159B: air outflow side, 160: head stack assembly, 161: support frame, 162: coil, 180: recording medium disk, 180M: spindle motor, 181: recording medium, 190: signal processing unit, AA, AR: arrow, D1: direction 1, H2: magnetic field, Hg 1: gap magnetic field, I1: current 1, Ic: current, Je: electron flow, L25: length, T1, T2: 1 st and 2 nd terminals, W1 and W2: 1 st and 2 nd wirings, i1 and i 2: 1 st and 2 nd currents, p1 to p 4: 1 st to 4 th parts, t21, t22, t 25: and (4) thickness.
Detailed Description
Embodiments of the present invention will be described below with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and the width of each portion, the ratio of the sizes of the portions, and the like are not necessarily the same as those in reality. Even when the same portions are shown, the sizes and ratios may be different from each other in the drawings.
In the present specification and the drawings, the same reference numerals are given to the same elements as those of the previously described configuration in the above drawings, and detailed description is appropriately omitted.
(embodiment 1)
Fig. 1(a) and 1(b) are schematic cross-sectional views illustrating a magnetic head of embodiment 1.
Fig. 1(b) is an enlarged view of a part of fig. 1 (a).
As shown in fig. 1(a), magnetic head 110 of the embodiment includes magnetic pole 30, 1 st shield 31, magnetic layer 25, 1 st conductive layer 21, and 2 nd conductive layer 22. A 2 nd shield 32 and a coil 30c are also provided in this example.
The magnetic pole 30 is located between the 1 st shield 31 and the 2 nd shield 32. For example, at least a portion of the coil 30c is located between the pole 30 and the 1 st shield 31. In this example, a portion of the coil 30c is located between the pole 30 and the 2 nd shield 32.
A recording circuit (2 nd circuit 30D) is electrically connected to the coil 30 c. A recording current is supplied from the recording circuit to the coil 30 c. A magnetic field (recording magnetic field) corresponding to the recording current is generated from the magnetic pole 30. The recording magnetic field is applied to the magnetic recording medium 80, and information is recorded in the magnetic recording medium 80. Thus, the recording circuit (2 nd circuit 30D) can supply a current (recording current) corresponding to the recorded information to the coil 30 c.
As shown in fig. 1(b), the magnetic layer 25 is disposed between the magnetic pole 30 and the 1 st shield 31. The 1 st conductive layer 21 is disposed between the magnetic pole 30 and the 1 st shield 31.
In this example, the 2 nd conductive layer 22 is disposed between the 1 st conductive layer 21 and the 1 st shield 31. As described below, the positions of the 1 st conductive layer 21 and the 2 nd conductive layer 22 may be replaced with each other. The 2 nd conductive layer 22 is provided at any one of the 1 st position between the 1 st conductive layer 21 and the 1 st shield 31 and the 2 nd position between the magnetic pole 30 and the 1 st conductive layer 21. In the example of fig. 1(b), the 2 nd conductive layer 22 is disposed at the 1 st position.
The direction from the magnetic pole 30 to the 1 st shield 31 is referred to as the 1 st direction D1. The direction from the 1 st conductive layer 21 to the magnetic layer 25 intersects the 1 st direction D1.
In this example, the 2 nd conductive layer 22 overlaps with a part (convex portion) of the 1 st shield 31 in the direction intersecting the 1 st direction D1. As described below, the 2 nd conductive layer 22 may overlap the magnetic layer 25 in the direction intersecting the 1 st direction D1.
The 1 st conductive layer 21 includes at least one selected from Cu, Ag, Au, Al, and Cr.
The 2 nd conductive layer 22 includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.
In one example, the 1 st conductive layer 21 includes Cu and the 2 nd conductive layer 22 includes Ta.
The 1 st conductive layer 21 and the 2 nd conductive layer 22 are nonmagnetic. The 1 st conductive layer 21 maintains spin polarization of electrons, for example. The 2 nd conductive layer 22 relaxes, for example, spin polarization of electrons.
For example, the 1 st conductive layer 21 is in contact with the magnetic layer 25. For example, the 2 nd conductive layer 22 is in contact with the 1 st conductive layer 21.
The thickness t21 (length) of the 1 st conductive layer 21 in the 1 st direction D1 is, for example, 10nm or more and 30nm or less. The thickness t22 (length) of the 2 nd conductive layer 22 in the 1 st direction D1 is, for example, 0.1nm or more and 10nm or less.
In the example shown in fig. 1(b), the thickness t21 is thicker than the thickness t 22.
The 1 st conductive layer 21 faces the side surface 25s of the magnetic layer 25. A magnetic action is generated between the 1 st conductive layer 21 and the side surface 25s of the magnetic layer 25. The magnetic action is, for example, torque based on the accumulation of spins. For example, by making the side surface 25s of the magnetic layer 25 relatively large, magnetic action is easily generated. Examples of magnetic effects are described later.
As shown in fig. 1(b), the magnetic layer 25 includes a 1 st surface 25a on the magnetic pole 30 side. The size of the side surface 25s may have a value relatively close to that of the 1 st surface 25 a. For example, the thickness t25 of the magnetic layer 25 in the 1 st direction D1 may be 0.2 times or more and 5 times or less the length of the 1 st face 25a in one direction of the 1 st face 25a (e.g., the length L25 shown in fig. 1 (b)). The thickness t25 corresponds to one of the lengths of the side faces 25 s. The length L25 may be, for example, a length in any direction perpendicular with respect to the 1 st direction D1.
As shown in fig. 1(a), for example, an insulating portion 30i is provided around the magnetic pole 30, the 1 st shield 31, the 2 nd shield 32, the coil 30c, the magnetic layer 25, the 1 st conductive layer 21, and the 2 nd conductive layer 22. In fig. 1(b), the insulating portion 30i is omitted.
The magnetic pole 30 is, for example, a main magnetic pole. A pole face 30F is provided at an end 30e of the magnetic pole 30. The pole face 30F is, for example, along the ABS (Air Bearing Surface) of the head 110. The magnetic pole face 30F faces the magnetic recording medium 80.
The direction perpendicular to the magnetic pole surface 30F is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is set as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is referred to as the Y-axis direction.
The Z-axis direction is, for example, a height direction. The X-axis direction is, for example, a down track (down track) direction. The Y-axis direction is a cross-track (cross track) direction.
For example, in the vicinity of the magnetic pole face 30F, the magnetic pole 30 is separated from the 1 st shield 31 in the X-axis direction. For example, in the vicinity of the pole face 30F, the 2 nd shield 32 is spaced away from the pole 30 in the X-axis direction. The magnetic head 110 and the magnetic recording medium 80 are relatively moved substantially in the X-axis direction. Thereby, information is recorded at an arbitrary position of the magnetic recording medium 80.
The 1 st shield 31 corresponds to, for example, a "trailing shield". The 2 nd shield 32 corresponds to, for example, "leading shield". The 1 st shield 31 is, for example, an auxiliary pole. The 1 st shield 31 can form a magnetic core together with the magnetic pole 30. For example, an additional shield such as a side shield (not shown) may be provided.
In the example shown in fig. 1(a) and 1(b), the 1 st direction D1 is inclined with respect to the X-Y plane.
As shown in fig. 1(b), the 1 st current I1 flows in the 1 st conductive layer 21 and the 2 nd conductive layer 22. In the example shown in fig. 1(b), the 1 st current I1 has a direction from the magnetic pole 30 to the 1 st shield 31 (a direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22). As described below, the direction of the 1 st current I1 may also have a direction from the 1 st shield 31 toward the magnetic pole 30 in other examples.
For example, the 1 st conductive layer 21 may be electrically connected with the magnetic pole 30. The 2 nd conductive layer 22 may be electrically connected to the 1 st shield 31. In this case, the 1 st current I1 described above may be supplied via the magnetic pole 30 and the 1 st shield 31.
As shown in fig. 1(a), a 1 st wire W1 and a 2 nd wire W2 may be provided. The 1 st wire W1 is electrically connected to the magnetic pole 30. The 2 nd wiring W2 is electrically connected to the 1 st shield 31. A 1 st terminal T1 and a 2 nd terminal T2 may be provided. The 1 st terminal T1 is electrically connected to the magnetic pole 30 via the 1 st wire W1. The 2 nd terminal T2 is electrically connected to the 1 st shield 31 via the 2 nd wire W2.
The 1 st current I1 is supplied from, for example, the 1 st circuit 20D (see fig. 1 a). For example, the 1 st current I1 can be supplied from the 1 st circuit 20D to the magnetic pole 30 and the 1 st shield 31 via the 1 st terminal T1, the 1 st wire W1, the 2 nd wire W2, and the 2 nd terminal T2.
In the embodiment, when the 1 st current I1 flows through the 1 st conductive layer 21 and the 2 nd conductive layer 22, for example, spin accumulation occurs at the interface between the 1 st conductive layer 21 and the magnetic pole 30 and the interface between the 2 nd conductive layer 22 and the 1 st shield 31. The spin is transferred (e.g., diffused) to the magnetic layer 25, and the direction of magnetization of the magnetic layer 25 can be inverted with respect to the magnetic field emitted from the magnetic pole 30. The spins act via the side 25s of the magnetic layer 25.
Fig. 2 is a schematic cross-sectional view illustrating the operation of the magnetic head according to embodiment 1.
In fig. 2, the magnetic pole 30, the 1 st shield 31, and the magnetic layer 25 are depicted, and other components (the 1 st conductive layer 21, the 2 nd conductive layer 22, and the like) are omitted.
The magnetic layer 25 has a magnetization 25M. A magnetic field H2 (recording magnetic field) is generated from the magnetic pole 30. At least a portion of the magnetic field H2 is a recording magnetic field. The magnetic field H2 enters the magnetic layer 25, assuming that the magnetization 25M of the magnetic layer 25 is not reversed as described above. On the other hand, as shown in fig. 2, when a current is supplied to the 1 st conductive layer 21 and the 2 nd conductive layer 22, the spin diffuses into the magnetic layer 25, and the direction of the magnetization 25M of the magnetic layer 25 is inverted with respect to the magnetic field H2, the magnetic field H2 hardly moves toward the magnetic layer 25. Thereby, the magnetic field H2 is directed toward the magnetic recording medium 80. The magnetic field H2 mostly enters the 1 st shield 31 through the magnetic recording medium 80 as a recording magnetic field. Therefore, a large amount of magnetic field H2 (recording magnetic field) is easily applied to the magnetic recording medium 80. The magnetic field H2 can be effectively applied to the magnetic recording medium 80 even when the write gap (writegap) is reduced.
In the embodiment, even when the write gap is reduced, the magnetic field H2 emitted from the magnetic pole 30 is suppressed from directly facing the 1 st shield 31 via the magnetic layer 25. As a result, the magnetic field H2 emitted from the magnetic pole 30 is directed toward the magnetic recording medium 80 in many cases, and the recording magnetic field is effectively applied to the magnetic recording medium 80. This can improve the recording density.
The magnetization 25M of the magnetic layer 25 is inverted when the direction of the 1 st current I1 is a predetermined direction. The direction of the 1 st current I1 for inversion depends on the materials of the 1 st conductive layer 21 and the 2 nd conductive layer 22. For example, when the 1 st conductive layer 21 includes a material that maintains spin polarization and the 2 nd conductive layer 22 includes a material that relaxes spin polarization of electrons, the magnetization 25M of the magnetic layer 25 is inverted when the 1 st current I1 flows from the 1 st conductive layer 21 to the 2 nd conductive layer 22. Examples of such materials correspond to Cu, Ag, Au, Al, Cr, and the like. Examples of other materials correspond to Ta, Pt, W, Ru, Mo, Ir, Rh, Pd, and the like.
As described above, the magnetization 25M of the magnetic layer 25 is inverted by the 1 st current I1. Since the magnetic pole 30, the magnetic layer 25, and the 1 st shield 31 are stacked, the resistance can be changed in the above-described stacked structure by the inversion of the magnetization 25M of the magnetic layer 25.
For example, the case where the magnetic layer 25 is electrically connected to the magnetic pole 30 and the 1 st shield 31 is as follows. The resistance when the recording current flows in the coil 30c and the current from the magnetic pole 30 to the 1 st shield 31 flows may be different from the resistance when the recording current flows in the coil 30c and the current from the 1 st shield 31 to the magnetic pole 30 flows. From the difference in resistance, information on the presence or absence of reversal of the magnetization 25M can be obtained. For example, the resistance when the recording current flows in the coil 30c and the 1 st current I1 flows from the magnetic pole 30 to the 1 st shield 31 may be different from the resistance when the recording current flows in the coil 30c and a current smaller than the 1 st current I1 flows between the 1 st shield 31 and the magnetic pole 30.
Hereinafter, examples of various magnetic heads according to the embodiment will be described. Hereinafter, a structure different from the magnetic head 110 will be described.
Fig. 3 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
As shown in fig. 3, in the magnetic head 111 of the embodiment, the 2 nd conductive layer 22 is provided between the magnetic pole 30 and the magnetic layer 25 (2 nd position). In this case, the 1 st current I1 also has a direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22. The 1 st current I1 has a direction from the 1 st shield 31 toward the pole 30. When the 1 st current I1 flows, the magnetization 25M of the magnetic layer 25 is inverted with respect to the magnetic field H2 (see fig. 2) from the magnetic pole 30. In this case, the recording magnetic field can be effectively applied to the magnetic recording medium 80. This can improve the recording density.
Fig. 4(a) and 4(b) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
As shown in fig. 4(a) and 4(b), in the magnetic heads 110a and 111a, the 2 nd conductive layer 22 overlaps the magnetic layer 25 in a direction intersecting the 1 st direction D1. The other configurations of the magnetic heads 110a and 111a are the same as those of the magnetic heads 110 and 111, respectively. The recording magnetic field can be effectively applied to the magnetic recording medium 80 also in the magnetic heads 110a and 111 a. This can improve the recording density.
Fig. 5 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
As shown in FIG. 5, magnetic head 120 of an embodiment includes conductive layers 3, 23, and 24 in addition to magnetic pole 30, shield 1, magnetic layer 25, conductive layer 1, 21, and conductive layer 2, 22.
In this example, the 2 nd conductive layer 22 is disposed at the 1 st position.
The 3 rd conductive layer 23 is disposed between the magnetic pole 30 and the magnetic layer 25. The 4 th conductive layer 24 is disposed between the magnetic layer 25 and the 1 st shield 31. The 3 rd conductive layer 23 and the 4 th conductive layer 24 are nonmagnetic.
The 3 rd conductive layer 23 includes at least one selected from Cu, Ag, Au, Al, and Cr. The 4 th conductive layer 24 includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. For example, the 3 rd conductive layer 23 may include the same material as that included in the 1 st conductive layer 21. For example, the 4 th conductive layer 24 may include the same material as the 2 nd conductive layer 22.
Current I1 has a direction from conductive layer 1, 21, to conductive layer 2, 22. Current I1 has a direction from conductive layer 3, 23, to conductive layer 4, 24.
By the 1 st current I1, magnetization 25M of magnetic layer 25 is more easily inverted with respect to magnetic field H2 derived from magnetic pole 30 by the action of conductive layers 23 and 24.
The recording magnetic field is more effectively applied to the magnetic recording medium 80. The recording density can be improved.
In the example of magnetic head 120, for example, conductive layer 3 23 interfaces with magnetic pole 30 and magnetic layer 25. The 4 th conductive layer 24 interfaces the magnetic layer 25 and the 1 st shield 31.
Fig. 6 is a schematic cross-sectional view illustrating the magnetic head of embodiment 1.
As shown in fig. 6, the magnetic head 121 of the embodiment also includes the 3 rd conductive layer 23 and the 4 th conductive layer 24 in addition to the magnetic pole 30, the 1 st shield 31, the magnetic layer 25, the 1 st conductive layer 21, and the 2 nd conductive layer 22.
In this example, the 2 nd conductive layer 22 is disposed at the 2 nd position.
The 3 rd conductive layer 23 is disposed between the magnetic layer 25 and the 1 st shield 31. The 4 th conductive layer 24 is disposed between the magnetic pole 30 and the magnetic layer 25. The 3 rd conductive layer 23 and the 4 th conductive layer 24 are nonmagnetic.
The 3 rd conductive layer 23 includes at least one selected from Cu, Ag, Au, Al, and Cr. The 4 th conductive layer 24 includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd.
In this case, the 1 st current I1 also has a direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22. Current I1 has a direction from conductive layer 3, 23, to conductive layer 4, 24.
By the 1 st current I1, magnetization 25M of magnetic layer 25 is more easily inverted with respect to magnetic field H2 derived from magnetic pole 30 by the action of conductive layers 23 and 24.
For example, the 3 rd conductive layer 23 interfaces with the magnetic layer 25 and the 1 st shield 31. The 4 th conductive layer 24 interfaces with the magnetic pole 30 and the magnetic layer 25.
Fig. 7(a) to 7(c) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
As shown in fig. 7(a), in the magnetic head 130 of the embodiment, the 1 st insulating layer 41 and the 2 nd insulating layer 42 are further provided in the configuration of the magnetic head 120.
The 1 st conductive layer 21 includes a 1 st portion p1 and a 2 nd portion p 2. The 1 st insulating layer 41 is disposed between the magnetic pole 30 and the 2 nd portion p 2. The 1 st portion p1 is disposed between the 1 st insulating layer 41 and the 3 rd conductive layer 23 in a direction crossing the 1 st direction D1.
The 2 nd conductive layer 22 includes a 3 rd portion p3 and a 4 th portion p 4. The 2 nd insulating layer 42 is disposed between the 1 st shield 31 and the 4 th portion p 4. The 3 rd portion p3 is disposed between the 2 nd insulating layer 42 and the 4 th conductive layer 24 in a direction crossing the 1 st direction D1.
The 1 st insulating layer 41 and the 2 nd insulating layer 42 function as, for example, a current confinement layer (current constriction layer). By providing the insulating layer described above, the 1 st current I1 effectively flows in the 1 st part p1 and the 3 rd part p3 close to the magnetic layer 25. For example, the magnetization 25M of the magnetic layer 25 can be effectively reversed.
The 1 st insulating layer 41 may be provided and the 2 nd insulating layer 42 may be omitted as in the magnetic head 130a shown in fig. 7 (b). The 2 nd insulating layer 42 may be provided and the 1 st insulating layer 41 may be omitted as in the magnetic head 130b shown in fig. 7 (c).
Fig. 8(a) to 8(c) are schematic cross-sectional views illustrating the magnetic head of embodiment 1.
As shown in fig. 8(a), in the magnetic head 131 of the embodiment, a 1 st insulating layer 41 and a 2 nd insulating layer 42 are further provided in the configuration of the magnetic head 121.
The 1 st conductive layer 21 includes a 1 st portion p1 and a 2 nd portion p 2. The 1 st insulating layer 41 is disposed between the 2 nd portion p2 and the 1 st shield 31. The 1 st portion p1 is disposed between the 1 st insulating layer 41 and the 3 rd conductive layer 23 in a direction crossing the 1 st direction D1.
The 2 nd conductive layer 22 includes a 3 rd portion p3 and a 4 th portion p 4. The 2 nd insulating layer 42 is disposed between the magnetic pole 30 and the 4 th portion p 4. The 3 rd portion p3 is disposed between the 2 nd insulating layer 42 and the 4 th conductive layer 24 in a direction crossing the 1 st direction D1.
In this case, the 1 st insulating layer 41 and the 2 nd insulating layer 42 also function as, for example, current confinement layers. The 1 st current I1 effectively flows in the 1 st part p1 and the 3 rd part p3 near the magnetic layer 25. For example, the magnetization 25M of the magnetic layer 25 can be effectively reversed.
The 1 st insulating layer 41 may be provided and the 2 nd insulating layer 42 may be omitted as shown in the magnetic head 131a shown in fig. 8 (b). The 2 nd insulating layer 42 may be provided and the 1 st insulating layer 41 may be omitted as in the magnetic head 131b shown in fig. 8 (c).
Fig. 9(a) to 9(d) are schematic plan views illustrating the magnetic head of embodiment 1.
These illustrations are plan views of the magnetic head as viewed from arrow AA (magnetic pole face 30F or ABS) shown in fig. 1 (a). The 2 nd shield 32 and the insulating portion are omitted in these drawings.
As shown in fig. 9(a) to 9(d), in magnetic heads 140 to 143, the direction from the 1 st conductive layer 21 toward the magnetic layer 25 intersects the direction from the magnetic pole 30 toward the 1 st shield 31. In this example, the direction from the 1 st conductive layer 21 toward the magnetic layer 25 is along the Y-axis direction. The direction from the 1 st conductive layer 21 toward the magnetic layer 25 is along the cross-track direction.
As shown in fig. 9(a) and 9(b), in the magnetic heads 140 and 141, the direction from a part of the 1 st conductive layer 21 toward the 3 rd conductive layer 23 is along the Y-axis direction. The direction from the 2 nd conductive layer 22 toward the 4 th conductive layer 24 is along the Y-axis direction. A current having a direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22 is supplied.
As shown in fig. 9(c) and 9(d), in magnetic heads 142 and 143, the direction from 1 st conductive layer 21 toward magnetic layer 25 is along the Y-axis direction, and the direction from 2 nd conductive layer 22 toward magnetic layer 25 is along the Y-axis direction. A current having a direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22 is supplied.
Fig. 10(a) and 10(b) are schematic diagrams illustrating an operation of the magnetic head according to the embodiment.
Fig. 10(a) shows an example of magnetic action in the 1 st conductive layer 21, the magnetic layer 25, and the 2 nd conductive layer 22. Fig. 10(b) shows an example of magnetic action in the 3 rd conductive layer 23, the magnetic layer 25, and the 4 th conductive layer 24.
As shown in fig. 10(a), the 1 st conductive layer 21, the 2 nd conductive layer 22, and the magnetic layer 25 are provided between the magnetic pole 30 and the 1 st shield 31.
A recording current is supplied from the 2 nd circuit 30D (see fig. 1 a) to the coil 30c of the magnetic pole 30. Thereby, the gap magnetic field Hg1 is generated from the magnetic pole 30. The gap magnetic field Hg1 is applied to the 1 st conductive layer 21, the 2 nd conductive layer 22, and the magnetic layer 25.
For example, the magnetization 30M of the pole 30 and the magnetization 31M of the 1 st shield 31 are substantially parallel to the gap magnetic field Hg 1. In a state before the current Ic (corresponding to the 1 st current I1) flows, the magnetization 25M of the magnetic layer 25 is substantially parallel to the gap magnetic field Hg 1.
The 1 st circuit 20D supplies a current Ic (corresponding to the 1 st current I1). In this case, the current Ic flows from, for example, the 1 st conductive layer 21 to the 2 nd conductive layer 22. At this time, the electron current Je flows. The electron current Je flows from the 2 nd conductive layer 22 to the 1 st conductive layer 21.
By the electron current Je, spin torque 31sp is generated at the interface between the 2 nd conductive layer 22 and the 1 st shield 31. The spin torque 31sp is, for example, a transmission type. On the other hand, a spin torque 30sp is generated at the interface between the 1 st conductive layer 21 and the magnetic pole 30 by the electron current Je. The spin torque 30sp is, for example, a reflection type. Due to the difference in the materials of the 1 st conductive layer 21 and the 2 nd conductive layer 22, the spin torque 30sp is larger than the spin torque 31 sp. The spin torque described above flows into the magnetic layer 25 by diffusion, and the magnetization 25M of the magnetic layer 25 changes. The magnetization 25M has a component opposite to the gap magnetic field Hg 1.
As shown in fig. 10(b), the 3 rd conductive layer 23, the magnetic layer 25, and the 4 th conductive layer 24 are provided between the magnetic pole 30 and the 1 st shield 31.
A recording current is supplied from the 2 nd circuit 30D (see fig. 1 a) to the coil 30c of the magnetic pole 30. Thereby, the gap magnetic field Hg1 is generated from the magnetic pole 30. A gap magnetic field Hg1 is applied to conductive layer 3, magnetic layer 25, and conductive layer 4 24.
For example, the magnetization 30M of the pole 30 and the magnetization 31M of the 1 st shield 31 are substantially parallel to the gap magnetic field Hg 1. In a state before the current Ic (corresponding to the 1 st current I1) flows, the magnetization 25M of the magnetic layer 25 is substantially parallel to the gap magnetic field Hg 1.
The 1 st circuit 20D supplies a current Ic (corresponding to the 1 st current I1). In this case, the current Ic flows from, for example, the 4 th conductive layer 24 to the 3 rd conductive layer 23. At this time, the electron current Je flows. The electron current Je flows from the 3 rd conductive layer 23 to the 4 th conductive layer 24.
By the electron flow Je, spin torque 23sp is generated at the interface between the 3 rd conductive layer 23 and the magnetic layer 25. The spin torque 23sp is, for example, a transmission type. On the other hand, a spin torque 24sp is generated at the interface between the magnetic layer 25 and the 4 th conductive layer 24 by the electron current Je. The spin torque 24sp is, for example, a reflection type. By the spin torque described above, the magnetization 25M of the magnetic layer 25 is inverted. The reversed magnetization 25M has a component opposite to the gap magnetic field Hg 1.
The current Ic may flow from the 3 rd conductive layer 23 toward the 4 th conductive layer 24, for example. At this time, the direction of spin torque 23sp and the direction of spin torque 24sp shown in fig. 10(b) are reversed. At this time, spin torque 23sp is a reflection type, and spin torque 24sp is a transmission type.
For example, by appropriately controlling the spin torque 23sp and the spin torque 24sp, the magnetization 25M of the magnetic layer 25 is easily inverted.
For example, the 4 th conductive layer 24 may include Ir. In this case, the thickness (length along the 1 st direction D1) of the 4 th conductive layer 24 is, for example, 0.3nm or more and 0.8nm or less. At this time, antiferromagnetic coupling easily occurs. For example, in the example of FIG. 1(b), the magnetic layer 25 is antiferromagnetically coupled to the 1 st shield 31. The magnetization 25M is easily inverted with respect to the magnetic field H2 originating from the magnetic pole 30.
(embodiment 2)
Embodiment 2 relates to a magnetic storage device. The magnetic storage device of the present embodiment includes a magnetic head, a magnetic recording medium 80 (e.g., a recording medium disk 180 described later), and a 1 st circuit 20D (see fig. 1 (a)). Information is recorded on the magnetic recording medium by a magnetic head (magnetic pole 30). As the magnetic head in embodiment 2, any of the magnetic heads ( magnetic heads 110, 110a, 111a, 120, 121, 130a, 130b, 131a, 131b, etc.) and modified magnetic heads according to embodiment 1 can be used. Hereinafter, a case of using the magnetic head 110 will be described.
As described above, the 1 st circuit 20D can supply the 1 st current I1 between the magnetic pole 30 and the 1 st shield 31. The magnetic memory device of the embodiment may further include a 2 nd circuit 30D (see fig. 1 (a)). As described above, the 2 nd circuit 30D can supply the current (recording current) corresponding to the information recorded on the magnetic recording medium 80 to the coil 30 c.
The magnetic head 110 can also perform tile recording on the magnetic recording medium 80. The recording density can be further improved.
Hereinafter, an example of the magnetic recording and reproducing device according to the present embodiment will be described.
Fig. 11 is a schematic perspective view illustrating a part of the magnetic recording and reproducing apparatus of the embodiment.
FIG. 11 illustrates a head slider.
The magnetic head 110 is provided to a head slider 159. The head slider 159 includes, for example, Al2O3and/TiC, etc. Head slider 159 with magnetic recordingThe medium floats on or comes into contact with the magnetic recording medium, and performs relative motion with respect to the magnetic recording medium.
The head slider 159 has, for example, an air inflow side 159A and an air outflow side 159B. The magnetic head 110 is disposed on the side of the air outflow side 159B of the head slider 159. Thus, the magnetic head 110 moves relative to the magnetic recording medium while floating above or in contact with the magnetic recording medium.
Fig. 12 is a schematic perspective view illustrating a magnetic recording and reproducing apparatus of the embodiment.
As shown in fig. 12, a rotary actuator is used in the magnetic recording and reproducing device 150 of the embodiment. The recording medium disk 180 is provided to a spindle motor 180M. The recording medium disk 180 is rotated in the direction of arrow AR by a spindle motor 180M. The spindle motor 180M responds to a control signal from the drive device control section. The magnetic recording and reproducing device 150 of the present embodiment may include a plurality of recording medium disks 180. The magnetic recording and reproducing device 150 may include a recording medium 181. The recording medium 181 is, for example, an SSD (Solid State Drive). The recording medium 181 uses a nonvolatile memory such as a flash memory. The magnetic recording and reproducing apparatus 150 may be, for example, a hybrid HDD (Hard Disk Drive).
The head slider 159 records and reproduces information recorded on the recording medium disk 180. The head slider 159 is provided at the tip of the film-like suspension 154. The magnetic head of the embodiment is provided near the tip of the head slider 159.
When the recording medium disk 180 rotates, the pressing force by the suspension 154 is balanced with the pressure generated on the medium opposing surface (ABS) of the head slider 159. The distance between the medium-facing surface of the head slider 159 and the surface of the recording medium disk 180 is a predetermined floating amount. In the embodiment, the head slider 159 may be in contact with the recording medium disk 180. For example, a contact movement type may be applied.
The suspension 154 is connected to one end of an arm 155 (e.g., an actuator arm). The arm 155 has, for example, a wire tube portion (bobbin). The bobbin portion holds a driving coil. A voice coil motor 156 is provided at the other end of the arm 155. The voice coil motor 156 is one of linear motors. The voice coil motor 156 includes, for example, a driving coil and a magnetic circuit. The drive coil is wound around the bobbin portion of the arm 155. The magnetic circuit includes a permanent magnet and an opposing yoke. A drive coil is provided between the permanent magnet and the opposing yoke. The suspension 154 has one end and the other end. The magnetic head is disposed at one end of the suspension 154. The arm 155 is connected to the other end of the suspension 154.
The arm 155 is held by a ball bearing. The ball bearings are provided at two positions above and below the bearing portion 157. The arm 155 can be rotated and slid by the voice coil motor 156. The magnetic head can be moved to an arbitrary position of the recording medium disk 180.
Fig. 13(a) and 13(b) are schematic perspective views illustrating a part of the magnetic recording and reproducing device of the embodiment.
Fig. 13(a) is an enlarged perspective view of the head stack assembly 160, illustrating a structure of a part of the magnetic recording and reproducing apparatus. Fig. 13(b) is a perspective view illustrating a head assembly (HGA) 158 which becomes a part of a head stack assembly (head stack assembly) 160.
As shown in fig. 13(a), the head stack assembly 160 includes a bearing portion 157, a head gimbal assembly 158, and a support bracket 161. A head gimbal assembly 158 extends from the bearing portion 157. The support frame 161 extends from the bearing portion 157. The support bracket 161 extends in the opposite direction to the head gimbal assembly 158. The support frame 161 supports the coil 162 of the voice coil motor 156.
As shown in fig. 13(b), the head gimbal assembly 158 has an arm 155 extending from the bearing portion 157 and a suspension 154 extending from the arm 155.
A head slider 159 is provided on the top end of the suspension 154. The head slider 159 is provided with the magnetic head of the embodiment.
