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 成田直幸
前田知幸 于 2019-03-12 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及磁记录再现装置。根据实施方式,磁头包括磁极、第1屏蔽区域、第2屏蔽区域以及第1层叠体。从所述磁极向所述第1屏蔽区域的方向沿着第1方向。从所述磁极向所述第2屏蔽区域的方向与所述第1方向交叉。所述第1层叠体设置于所述磁极与所述第2屏蔽区域之间。所述第1层叠体包括：第1磁性层,包含选自Fe、Co以及Ni中的至少一个；第1导电层,设置于所述磁极与所述第1磁性层之间；以及第2导电层,设置于所述第1磁性层与所述第2屏蔽区域之间。所述第1方向沿着所述磁极相对的磁记录介质与所述磁极之间的相对的移动方向。(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, a1 st shield region, a2 nd shield region, and a1 st stack. The direction from the magnetic pole to the 1 st shield region is along the 1 st direction. A direction from the magnetic pole toward the 2 nd shield region intersects the 1 st direction. The 1 st stacked body is disposed between the magnetic pole and the 2 nd shield region. The 1 st stack includes: a1 st magnetic layer containing at least one selected from the group consisting of Fe, Co, and Ni; the 1 st conducting layer is arranged between the magnetic pole and the 1 st magnetic layer; and a2 nd conductive layer disposed between the 1 st magnetic layer and the 2 nd shielding region. The 1 st direction is along a relative moving direction between the magnetic recording medium whose magnetic poles are opposed and the magnetic poles.)
1. A magnetic head includes:
a magnetic pole;
a1 st shield region along a1 st direction from the magnetic pole toward the 1 st shield region;
a2 nd shield region, a direction from the magnetic pole to the 2 nd shield region intersecting the 1 st direction; and
a1 st stacked body provided between the magnetic pole and the 2 nd shield region,
the 1 st stack includes:
a1 st magnetic layer containing at least one selected from the group consisting of Fe, Co, and Ni;
the 1 st conducting layer is arranged between the magnetic pole and the 1 st magnetic layer; and
a2 nd conductive layer disposed between the 1 st magnetic layer and the 2 nd shield region,
the 1 st direction is along a relative moving direction between the magnetic recording medium whose magnetic poles are opposed and the magnetic poles.
2. A magnetic head includes:
a magnetic pole;
a1 st shield region along a1 st direction from the magnetic pole toward the 1 st shield region;
a2 nd shield region, a direction from the magnetic pole to the 2 nd shield region intersecting the 1 st direction; and
a1 st stacked body provided between the magnetic pole and the 2 nd shield region,
the 1 st stack includes:
a1 st magnetic layer containing at least one selected from the group consisting of Fe, Co, and Ni;
the 1 st conducting layer is arranged between the magnetic pole and the 1 st magnetic layer and is connected with the magnetic pole and the 1 st magnetic layer; and
and the 2 nd conducting layer is arranged between the 1 st magnetic layer and the 2 nd shielding region and is connected with the 1 st magnetic layer and the 2 nd shielding region.
3. The magnetic head as claimed in claim 1,
the 1 st conductive layer includes at least one selected from Cu, Ag, Al and Au,
the 2 nd conductive layer contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd,
the 1 st current can be passed in a direction from the 1 st conductive layer to the 2 nd conductive layer.
4. The magnetic head as claimed in claim 1,
the 1 st conductive layer contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd,
the 2 nd conductive layer contains at least one selected from Cu, Ag, Al and Au,
the 1 st current can be passed in a direction from the 2 nd conductive layer to the 1 st conductive layer.
5. A magnetic head as claimed in claim 3,
a1 st resistance between the magnetic pole and the 2 nd shield region when a1 st current flows between the magnetic pole and the 2 nd shield region is different from a2 nd resistance between the magnetic pole and the 2 nd shield region when another current flows between the magnetic pole and the 2 nd shield region, and a direction of the another current is opposite to a direction of the 1 st current.
6. A magnetic head includes:
a magnetic pole;
1 st shield region;
a2 nd shielding region;
a 3 rd shield region which crosses a1 st direction from the magnetic pole to the 1 st shield region in a direction from the 3 rd shield region to the 2 nd shield region, at least a part of the magnetic pole being provided between the 3 rd shield region and the 2 nd shield region in the direction from the 3 rd shield region to the 2 nd shield region;
a1 st stacked body provided between the magnetic pole and the 2 nd shield region; and
a2 nd stacked body provided between the magnetic pole and the 3 rd shield region,
the 1 st stack includes:
a1 st magnetic layer containing at least one selected from the group consisting of Fe, Co, and Ni;
the 1 st conducting layer is arranged between the magnetic pole and the 1 st magnetic layer; and
a2 nd conductive layer disposed between the 1 st magnetic layer and the 2 nd shield region,
the 2 nd stack includes:
a2 nd magnetic layer containing at least one selected from Fe, Co, and Ni;
a 3 rd conductive layer disposed between the magnetic pole and the 2 nd magnetic layer; and
and the 4 th conducting layer is arranged between the 2 nd magnetic layer and the 3 rd shielding region.
7. A magnetic head as claimed in claim 6,
the 1 st conductive layer includes at least one selected from Cu, Ag, Al and Au,
the 2 nd conductive layer contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd,
the 3 rd conductive layer includes at least one selected from Cu, Ag, Al and Au,
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 6,
the 1 st conductive layer contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd,
the 2 nd conductive layer contains at least one selected from Cu, Ag, Al and Au,
the 3 rd conductive layer contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh and Pd,
the 4 th conductive layer includes at least one selected from Cu, Ag, Al, and Au.
9. A magnetic recording/reproducing apparatus includes:
the magnetic head of claim 6;
a magnetic recording medium through which information is recorded; and
and a1 st circuit capable of supplying a current to the 1 st layered body.
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 and 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, a1 st shield region, a2 nd shield region, and a1 st stack. The direction from the magnetic pole to the 1 st shield region is along the 1 st direction. A direction from the magnetic pole toward the 2 nd shield region intersects the 1 st direction. The 1 st stacked body is disposed between the magnetic pole and the 2 nd shield region. The 1 st stack includes: a1 st magnetic layer containing at least one selected from the group consisting of Fe, Co, and Ni; the 1 st conducting layer is arranged between the magnetic pole and the 1 st magnetic layer; and a2 nd conductive layer disposed between the 1 st magnetic layer and the 2 nd shielding region. The 1 st direction is along a relative moving direction between the magnetic recording medium whose magnetic poles are opposed and the magnetic poles.
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 views illustrating a magnetic head according to embodiment 1.
Fig. 2 is a schematic view illustrating the magnetic head according to embodiment 1.
Fig. 3 is a schematic diagram illustrating an operation of the magnetic head according to embodiment 1.
Fig. 4 is a diagram illustrating characteristics of a magnetic head.
Fig. 5 is a schematic diagram illustrating an operation of the magnetic head according to the embodiment.
Fig. 6 is a schematic perspective view illustrating a part of the magnetic recording and reproducing device according to the embodiment.
Fig. 7 is a schematic perspective view illustrating a magnetic recording and reproducing apparatus according to an embodiment.
Fig. 8(a) and 8(b) are schematic perspective views illustrating a part of the magnetic recording and reproducing device according to the embodiment.
Description of the reference symbols
11. 12: 1 st and 2 nd magnetic layers;
11M, 12M: magnetizing;
20D: a1 st circuit;
21-24: the 1 st to 4 th conductive layers;
21sp, 22 sp: a spin torque;
30: a magnetic pole;
30D: a2 nd circuit;
30F: the 1 st surface;
30M: magnetizing;
30 c: a coil;
30 i: an insulating section;
30M: magnetizing;
31-34: 1 st to 4 th shield regions;
32M: magnetizing;
80: a magnetic recording medium;
110: a magnetic head;
150: a magnetic recording and reproducing device;
154: a suspension;
155: an arm;
156: a voice coil motor;
157: a bearing portion;
158: a head gimbal assembly;
159: a head slider;
159A: an air inflow side;
159B: an air outflow side;
160: a head stack assembly;
161: a support frame;
162: a coil;
180: a recording medium disk;
180M: a spindle motor;
181: a recording medium;
190: a signal processing unit;
AF. AR 1: an arrow;
D1-D3: the 1 st direction;
H1-H3: a magnetic field;
HT: a height;
hg 1: a gap magnetic field;
HS: magnetic field strength;
ic: current flow;
je: a stream of electrons;
l1: a length;
SB1, SB 2: 1 st and 2 nd laminated bodies;
T1-T3: 1 st to 3 rd terminals;
W1-W3: 1 st to 3 rd wirings;
i1, i 2: 1 st and 2 nd currents;
pY: a location;
t11, t12, t21, t22, t23, t 24: 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 drawings, 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 practice. Even when the same portions are indicated, the sizes and ratios of the portions may be indicated differently according to the drawings.
In the present specification and the drawings, the same elements as those described in the previous drawings are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.
(embodiment 1)
Fig. 1(a), 1(b), and 2 are schematic views illustrating a magnetic head according to embodiment 1.
FIG. 1(a) is a sectional view taken along line B1-B2 of FIG. 1 (B). Fig. 1(b) is a plan view as seen from an arrow AR1 in fig. 1 (a). FIG. 2 is a cross-sectional view taken along line A1-A2 of FIG. 1 (a).
As shown in fig. 1(b), a magnetic head 110 according to the embodiment includes a magnetic pole 30, a1 st shield region 31, a2 nd shield region 32, and a1 st stacked body SB 1. In this example, the 3 rd shield region 33 and the 2 nd stacked body SB2 are also provided. In the cross section shown in fig. 1(a), the 2 nd shield region 32, the 1 st stacked body SB1, the 3 rd shield region 33, and the 2 nd stacked body SB2 are not visible. In fig. 1(a), the positions of the 1 st stacked body SB1 and the 2 nd stacked body SB2 are indicated by broken lines.
As shown in fig. 1(a), a coil 30c and a 4 th shield region 34 are also provided.
The direction from the magnetic pole 30 to the 1 st shield region 31 is along the 1 st direction D1 (see fig. 1(a) and 1 (b)). The 1 st direction is defined as the X-axis direction. One direction perpendicular to the X-axis direction is set as the Z-axis direction. The direction perpendicular to the X-axis direction and the Z-axis direction is referred to as the Y-axis direction.
The magnetic pole 30 is, for example, a main magnetic pole. The pole 30 includes a1 st face 30F. The 1 st face 30F is opposed to the magnetic recording medium 80. The 1 st face 30F corresponds to, for example, the medium opposing face. The 1 st Surface 30F corresponds to, for example, an ABS (Air Bearing Surface).
The pole 30 is located between the 1 st and 4 th shield regions 31 and 34. At least a portion of the coil 30c is located between the pole 30 and the 1 st shield region 31. In this example, a portion of coil 30c is located between pole 30 and 4 th shield region 34.
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. A recording magnetic field is applied to the magnetic recording medium 80, recording information to the magnetic recording medium 80. In this manner, the recording circuit (2 nd circuit 30D) can supply a current (recording current) corresponding to the recorded information to the coil 30 c.
For example, a direction perpendicular to the 1 st surface 30F is referred to as a Z-axis direction. The Z-axis direction is, for example, a height direction. The X-axis direction is, for example, the track direction. The Y-axis direction is, for example, a cross-track direction. The 1 st direction D1(X axis direction) is along the relative moving direction between the magnetic recording medium 80 and the magnetic pole 30 where the magnetic pole 30 is opposed. The angle between the 1 st direction D1 and the direction of relative movement between the magnetic recording medium 80 and the magnetic pole 30 is ± 25 degrees or less. The angle may be ± 20 degrees or less. The absolute value of the angle between the 1 st direction D1 and the along-track direction is smaller than the absolute value of the angle between the 1 st direction D1 and the cross-track direction.
The 1 st shield region 31 corresponds to, for example, "trailing shield: trailing shield ". The 4 th shielding region 34 corresponds to, for example, "leading shield: leading shield ". The 1 st shield region 31 is, for example, an auxiliary magnetic pole. The 1 st shield region 31 can form a magnetic core together with the magnetic pole 30. For example, the 4 th shield region 34 may also form a magnetic core with the magnetic pole 30.
As shown in fig. 1(a), for example, an insulating portion 30i is provided around the magnetic pole 30.
As shown in fig. 1 b, a direction from the magnetic pole 30 to the 2 nd shield region 32 (for example, the 2 nd direction D2) intersects with the 1 st direction D1 (X-axis direction). The direction from the magnetic pole 30 to the 3 rd shield region 33 (for example, the 3 rd direction D3) intersects with the 1 st direction D1 (X-axis direction).
For example, the direction from the 3 rd shield region 33 to the 2 nd shield region 32 intersects with the 1 st direction D1 (X-axis direction). The direction from the 3 rd shield region 33 to the 2 nd shield region 32 is, for example, along the Y-axis direction. At least a part of the magnetic pole 30 is disposed between the 3 rd shield region 33 and the 2 nd shield region 32 in the above-described direction (for example, the Y-axis direction) from the 3 rd shield region 33 to the 2 nd shield region 32.
The 2 nd shield region 32 corresponds to, for example, the 1 st side shield. The 3 rd shield region 33 corresponds to, for example, the 2 nd side shield.
As shown in fig. 1(b), the 1 st stacked body SB1 is provided between the magnetic pole 30 and the 2 nd shield region 32.
The 1 st stacked body SB1 includes a1 st magnetic layer 11, a1 st conductive layer 21, and a2 nd conductive layer 22. The 1 st magnetic layer 11 contains at least one selected from Fe, Co, and Ni. The 1 st magnetic layer 11 is, for example, a FeCo layer or a FeNi layer. The 1 st magnetic layer 11 is, for example, ferromagnetic. The 1 st magnetic layer 11 contains, for example, a ferromagnetic metal.
The 1 st conductive layer 21 is disposed between the magnetic pole 30 and the 1 st magnetic layer 11. The 2 nd conductive layer 22 is disposed between the 1 st magnetic layer 11 and the 2 nd shielding region 32. The 1 st conductive layer 21 and the 2 nd conductive layer 22 are, for example, nonmagnetic. The 1 st conductive layer 21 and the 2 nd conductive layer 22 contain, for example, a nonmagnetic metal.
In one example, the 1 st conductive layer 21 interfaces with the magnetic pole 30 and the 1 st magnetic layer 11. In one example, the 2 nd conductive layer 22 interfaces with the 1 st magnetic layer 11 and the 2 nd shield region 32.
The 2 nd laminated body SB2 is provided between the magnetic pole 30 and the 3 rd shield region 33. The 2 nd laminated body SB2 includes a2 nd magnetic layer 12, a 3 rd conductive layer 23, and a 4 th conductive layer 24. The 2 nd magnetic layer 12 contains at least one selected from Fe, Co, and Ni. The 2 nd magnetic layer 12 is, for example, a FeCo layer or a FeNi layer. The 2 nd magnetic layer 12 is, for example, ferromagnetic. The 2 nd magnetic layer 12 contains, for example, a ferromagnetic metal.
The 3 rd conductive layer 23 is disposed between the magnetic pole 30 and the 2 nd magnetic layer 12. The 4 th conductive layer 24 is disposed between the 2 nd magnetic layer 12 and the 3 rd shielding region 33. The 3 rd conductive layer 23 and the 4 th conductive layer 24 are, for example, nonmagnetic. The 3 rd conductive layer 23 and the 4 th conductive layer 24 contain, for example, a nonmagnetic metal.
In one example, conductive layer 3 23 interfaces with magnetic pole 30 and magnetic layer 2 12. In one example, the 4 th conductive layer 24 interfaces with the 2 nd magnetic layer 12 and the 3 rd shielded region 33.
For example, the thickness of the 1 st magnetic layer 11 along the direction from the magnetic pole 30 to the 2 nd shield region 32 (the 2 nd direction D2) is set to be the thickness t 11. The thickness t11 is, for example, 4nm or more and 20nm or less.
The thickness of the 1 st conductive layer 21 in the direction from the magnetic pole 30 to the 2 nd shield region 32 (the 2 nd direction D2) is set to a thickness t 21. The thickness of the 2 nd conductive layer 22 along the 2 nd direction D2 is set to a thickness t 22. The thickness t21 and the thickness t22 are, for example, 0.3nm or more and 15nm or less, respectively.
As will be described later, with such a thickness, for example, the magnetization of the 1 st magnetic layer 11 is easily oriented in a desired direction.
For example, the thickness of the 2 nd magnetic layer 12 along the direction from the magnetic pole 30 to the 3 rd shield region 33 (the 3 rd direction D3) is set to be the thickness t 12. The thickness t12 is, for example, 4nm or more and 20nm or less.
The thickness of the 3 rd conductive layer 23 along the direction from the magnetic pole 30 to the 3 rd shielding region 33 (the 3 rd direction D3) is set to a thickness t 23. The thickness of the 4 th conductive layer 24 along the 3 rd direction D3 is set to a thickness t 24. The thickness t23 and the thickness t24 are, for example, 0.3nm or more and 15nm or less, respectively.
As will be described later, with such a thickness, for example, the magnetization of the 2 nd magnetic layer 12 is easily oriented in a desired direction.
As shown in fig. 2, in one example, the 1 st to 3 rd terminals T1 to T3 are provided. The 1 st terminal T1 is electrically connected to the magnetic pole 30. The 2 nd terminal T2 is electrically connected to the 2 nd shield region 32. The 3 rd terminal T3 is electrically connected to the 3 rd shielding region 33. The 2 nd terminal T2 may be electrically connected to at least either one of the 2 nd shield region 32 and the 3 rd shield region 33. In the case where the 2 nd terminal T2 is electrically connected to the 2 nd and 3 rd shielding regions 32 and 33, the 3 rd terminal T3 may be omitted.
For example, the 1 st to 3 rd wirings W1 to W3 may be provided. The 1 st wire W1 is electrically connected to the 1 st terminal T1. The 2 nd wire W2 is electrically connected to the 2 nd terminal T2. The 3 rd wire W3 is electrically connected to the 3 rd terminal T3.
For example, the 1 st to 3 rd wires W1 to W3 are electrically connected to the 1 st circuit 20D. The 1 st circuit 20D can supply the 1 st current i1 to the 1 st stacked body SB 1. The 1 st circuit 20D can supply the 2 nd current i2 to the 2 nd stack SB 2.
The 1 st current i1 is supplied to the 1 st stacked body SB1 via the magnetic pole 30 and the 2 nd shield region 32, for example. The 1 st current i1 flows in the 1 st conductive layer 21, the 1 st magnetic layer 11, and the 2 nd conductive layer 22. The direction of the 1 st current i1 will be described later.
The 2 nd current i2 is supplied to the 2 nd stacked body SB2 via the magnetic pole 30 and the 3 rd shield region 33, for example. The 2 nd current i2 flows in the 3 rd conductive layer 23, the 2 nd magnetic layer 12, and the 4 th conductive layer 24. The direction of the 2 nd current i2 will be described later.
The 1 st current i1 and the 2 nd current i2 have direct current components. The current is, for example, a direct current.
For example, the material of the 1 st conductive layer 21 may be different from the material of the 2 nd conductive layer 22. For example, the material of the 3 rd conductive layer 23 may be different from the material of the 4 th conductive layer 24.
When a current flows through such a stacked body (at least any one of the 1 st stacked body SB1 and the 2 nd stacked body SB 2), the direction of magnetization of the magnetic layer (at least any one of the 1 st magnetic layer 11 and the 2 nd magnetic layer 12) included in the stacked body can be controlled. For example, the magnetization of the magnetic layer has a component opposite to the direction of the magnetic field emitted from the magnetic pole 30. This makes it possible to appropriately control the distribution of the direction of the magnetic field emitted from the magnetic pole 30.
Preferably, the 1 st terminal T1 and the 2 nd terminal T2 do not have other electrical connections through the 1 st stacked body SB 1. Preferably, the 1 st terminal T1 and the 3 rd terminal T3 do not have other electrical connections through the 2 nd stacked body SB 2.
Fig. 3 is a schematic diagram illustrating an operation of the magnetic head according to embodiment 1.
A recording current flows in the coil 30c, thereby generating a magnetic field from the magnetic pole 30. A part of the magnetic field emitted from the magnetic pole 30 (magnetic field H1) is directed toward the magnetic recording medium 80. On the other hand, the other part of the magnetic field emitted from the magnetic pole 30 (magnetic field H2) has a component toward the 2 nd shield region 32. At this time, when a current (1 st current i1) flows in the 1 st stack SB1, the magnetization 11M of the 1 st magnetic layer 11 has a component opposite to the magnetic field H2. This makes it difficult for the magnetic field H2 to pass through the 1 st magnetic layer 11. As a result, the magnetic field H2 is easily directed toward the magnetic recording medium 80. This enables the intensity of the recording magnetic field to be changed rapidly at the end in the cross-track direction (the end on the 2 nd shield region 32 side).
Similarly, the other part of the magnetic field emitted from the magnetic pole 30 (magnetic field H3) has a component toward the 3 rd shield region 33. When a current (2 nd current i2) flows in the 2 nd stacked body SB2, the magnetization 12M of the 2 nd magnetic layer 12 has a component opposite to the magnetic field H3. This makes it difficult for the magnetic field H3 to pass through the 2 nd magnetic layer 12. As a result, the magnetic field H3 is easily directed toward the magnetic recording medium 80. This enables the intensity of the recording magnetic field to be changed rapidly at the end in the cross-track direction (the end on the 3 rd shield region 33 side).
In an embodiment, for example, the distribution of the recording magnetic field across the track direction can be controlled. For example, the steepness of the end of the recording magnetic field can be improved. Thus, for example, even if the interval in the cross-track direction of the plurality of tracks is narrowed, good recording and reproducing characteristics can be obtained.
According to the embodiment, a magnetic head and a magnetic recording and reproducing apparatus capable of improving recording density can be provided.
For example, tile Recording (shift Recording) is sometimes performed. In the shingle recording, a2 nd track is overlapped on a part of a1 st track to be recorded, and the 2 nd track is recorded. By being able to control the distribution of the recording magnetic field across the track direction well, the tile recording can be performed more well.
In the embodiment, by providing the 1 st stacked body SB1, the distribution of the recording magnetic field on the 2 nd shield region 32 side can be controlled. By providing the 2 nd laminated body SB2, the distribution of the recording magnetic field on the 3 rd shield region 33 side can be controlled. In the embodiment, one of the 1 st layered body SB1 and the 2 nd layered body SB2 may be provided.
In one example, the 1 st conductive layer 21 includes at least one selected from Cu, Ag, Al, and Au. In this case, the 2 nd conductive layer 22 is preferably at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd, for example. In this case, the 1 st current i1 in the direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22 can be applied. In this case, the magnetization 11M of the 1 st magnetic layer 11 has a component opposite to the magnetic field emitted from the magnetic pole 30.
In other examples, the 1 st conductive layer 21 includes at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. In this case, the 2 nd conductive layer 22 preferably contains at least one selected from Cu, Ag, Al, and Au, for example. In this case, the 1 st current i1 in the direction from the 2 nd conductive layer 22 to the 1 st conductive layer 21 can be applied. In this case, the magnetization 11M of the 1 st magnetic layer 11 has a component opposite to the magnetic field emitted from the magnetic pole 30.
The resistance of the 1 st stacked body SB1 when the magnetization 11M of the 1 st magnetic layer 11 has a component opposite to the magnetic field emitted from the magnetic pole 30 by the 1 st current i1 may be changed from the resistance when the 1 st current i1 is not applied.
For example, the resistance between the magnetic pole 30 and the 2 nd shield region 32 when the 1 st current i1 flows between the magnetic pole 30 and the 2 nd shield region 32 is set to the 1 st resistance. The resistance between the magnetic pole 30 and the 2 nd shield region 32 when the 3 rd current flows between the magnetic pole 30 and the 2 nd shield region 32 is set as the 2 nd resistance. The 1 st resistance is different from the 2 nd resistance. The direction of the 3 rd current is opposite to the direction of the 1 st current i 1.
For example, with a1 st current i1, the magnetization 11M of the 1 st magnetic layer 11 is inverted with respect to the magnetic field from the magnetic pole 30. For example, when the 3 rd current flows, the magnetization 11M of the 1 st magnetic layer 11 is not inverted with respect to the magnetic field from the magnetic pole 30. In one example, the 1 st resistance is higher than the 2 nd resistance.
For example, the resistance between the magnetic pole 30 and the 3 rd shield region 33 when the 2 nd current i2 flows between the magnetic pole 30 and the 3 rd shield region 33 is set to the 3 rd resistance. The resistance between the magnetic pole 30 and the 3 rd shield region 33 when the 4 th current flows between the magnetic pole 30 and the 3 rd shield region 33 is set as the 4 th resistance. The 4 th resistance is different from the 3 rd resistance. The direction of the 4 th current is opposite to the direction of the 2 nd current i 2.
For example, with a2 nd current i2, the magnetization 12M of the 2 nd magnetic layer 12 is reversed with respect to the magnetic field from the magnetic pole 30. For example, when the 4 th current described above flows, the magnetization 12M of the 2 nd magnetic layer 12 is not inverted with respect to the magnetic field from the magnetic pole 30. In one example, the 3 rd resistance is higher than the 4 th resistance.
The difference in resistance described above is based on the magnetoresistance effect, for example.
In one example, the 1 st conductive layer 21 includes at least one selected from Cu, Ag, Al, and Au. At this time, the 2 nd conductive layer 22 preferably contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. At this time, the 3 rd conductive layer 23 includes at least one selected from Cu, Ag, Al, and Au. At this time, the 4 th conductive layer 24 preferably contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. At this time, the 1 st current i1 in the direction from the 1 st conductive layer 21 to the 2 nd conductive layer 22 can be applied. At this time, current i2 of the 2 nd current in the direction from conductive layer 3 to conductive layer 4 24 can be applied.
In one example, the 2 nd conductive layer 22 includes at least one selected from Cu, Ag, Al, and Au. At this time, the 1 st conductive layer 21 preferably contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. At this time, the 4 th conductive layer 24 includes at least one selected from Cu, Ag, Al, and Au. At this time, the 3 rd conductive layer 23 preferably contains at least one selected from Ta, Pt, W, Ru, Mo, Ir, Rh, and Pd. At this time, the 1 st current i1 in the direction from the 2 nd conductive layer 22 to the 1 st conductive layer 21 can be applied. At this time, the 2 nd current i2 in the direction from the 4 th conductive layer 24 to the 3 rd conductive layer 23 can be applied.
By using conductive materials different from each other in the 1 st conductive layer 21 and the 2 nd conductive layer 22, the magnetization 11M of the 1 st magnetic layer 11 is easily inverted. By using conductive materials different from each other in the 3 rd conductive layer 23 and the 4 th conductive layer 24, the magnetization 12M of the 2 nd magnetic layer 12 is easily inverted.
An example of the simulation result of the characteristics of the magnetic head will be described below. In the simulated model 1, the height HT (see fig. 2) of the 1 st magnetic layer 11 in the Z-axis direction was 40 nm. The length L1 (see fig. 1 b) of the 1 st magnetic layer 11 was 60 nm. As shown in fig. 1(b), the length L1 is the length of the 1 st magnetic layer 11 in the direction along the plane including the 1 st face 30F. The length L1 is the length of the 1 st magnetic layer 11 in the direction perpendicular to the direction from the magnetic pole 30 to the 2 nd shield region 32. The height of the 2 nd magnetic layer 12 in the Z-axis direction is the same as the height HT of the 1 st magnetic layer 11. The length of the 2 nd magnetic layer 12 is the same as the length L1 of the 1 st magnetic layer 11. The 1 st magnetic layer 11 and the 2 nd magnetic layer 12 are provided at positions symmetrical to each other with respect to an axis passing through the center of the magnetic pole 30 in the Y axis direction and along the X axis direction (see fig. 1 (b)).
The parameters in the case of using the FeNi alloy are applied to the 1 st magnetic layer 11 and the 2 nd magnetic layer 12. The saturation magnetization of each of the 1 st magnetic layer 11 and the 2 nd magnetic layer 12 is 1T (tesla).
The thickness t11 and the thickness t12 (see fig. 1(b)) were each 10 nm. The thickness t21 and the thickness t23 (see fig. 1(b)) were each 15 nm. The thickness t22 and the thickness t24 (see fig. 1(b)) were each 15 nm. The distance between the magnetic pole 30 and the 2 nd shield region 32 and the distance between the magnetic pole 30 and the 3 rd shield region 33 are 40nm, respectively. In the 1 st model, the 1 st current i1 (see fig. 2) flows through the 1 st stacked body SB 1. The 2 nd current i2 (see fig. 2) flows through the 2 nd stacked body SB 2.
In the 2 nd model, the 1 st stack SB1 and the 2 nd stack SB2 were not provided. In model 2, an insulating layer (the same material as the insulating portion 30 i) is provided in a region between the magnetic pole 30 and the 2 nd shield region 32 and a region between the magnetic pole 30 and the 3 rd shield region 33. In the 2 nd model, the distance between the magnetic pole 30 and the 2 nd shield region 32 and the distance between the magnetic pole 30 and the 3 rd shield region 33 are 40nm, respectively.
The 3 rd model has the same constitution as the 1 st model. In the 3 rd model, the current was not supplied to the 1 st stack SB1 and the 2 nd stack SB 2.
Fig. 4 is a diagram illustrating characteristics of a magnetic head.
Fig. 4 illustrates simulation results of the characteristics of the 1 st to 3 rd models M1 to M3. The horizontal axis of fig. 4 represents the position py (nm) in the cross-track direction (Y-axis direction). The position where the position pY is 0nm corresponds to the center of the magnetic pole 30. The vertical axis of fig. 4 is the magnetic field strength hs (oe) applied from the magnetic pole 30 to the magnetic recording medium 80. The magnetic field strength HS is the maximum magnetic field strength in the track direction (X-axis direction) of the position pY.
Fig. 4 corresponds to the "off-track illustration". Preferably, in the off-track plot, the magnetic field strength HS changes (e.g., decays) sharply in the direction of the position pY. The magnetic field strength HS changes abruptly, so that a high recording density can be obtained.
As shown in fig. 4, in the 3 rd model M3, the maximum value of the magnetic field strength HS is increased as compared with the 2 nd model M2. However, in the 3 rd model M3, the steepness of the attenuation of the magnetic field strength HS is reduced as compared with the 2 nd model M2. This is considered to be because: in model 3M 3, the magnetization in the side shields (2 nd shield region 32 and 3 rd shield region 33) is saturated.
In contrast, in the 1 st model M1, the maximum value of the magnetic field strength HS is increased as compared with the 2 nd model M2 and the 3 rd model M3. Further, in the 1 st model M1, the steepness of the attenuation of the magnetic field strength HS is higher than in the 2 nd model M2 and the 3 rd model M3. In the 1 st model M1, a high recording density can be obtained. In the 1 st model M1, a current flows through the 1 st stack SB1 and the 2 nd stack SB 2. Thereby, the magnetization 11M of the 1 st magnetic layer 11 and the magnetization 12M of the 2 nd magnetic layer 12 are inverted. From this, it is considered that the steepness of the attenuation of the magnetic field strength HS becomes high.
For example, in fig. 4, the off-track magnetic field gradient (Oe/nm) can be calculated from the magnetic field strength HS at the position pY of 40nm and the magnetic field strength HS at the position pY of 0 nm. In each of the 1 st to 3 rd models M1 to M3, the off-orbit magnetic field gradient (Oe/nm) can be normalized by the maximum value of the magnetic field strength HS. The normalized off-orbit magnetic field gradient (1/nm) can be derived in each of the 1 st to 3 rd models M1 to M3. The normalized off-track magnetic field gradient is negative. The case where the absolute value of the normalized off-track magnetic field gradient is large corresponds to the case where the steepness is high. Preferably, the absolute value of the off-track magnetic field gradient is large.
In model 1M 1, the normalized off-track magnetic field gradient was-1.82 × 10-2And/nm. In model 2M 2, the normalized off-track magnetic field gradient was-1.4X 10-2And/nm. In model 3M 3, the normalized off-track magnetic field gradient was-1.1X 10-2/nm。
Hereinafter, in the 1 st model M1, an example of characteristics when the height HT (see fig. 2) of the 1 st magnetic layer 11 in the Z-axis direction is changed will be described. At this time, the height of the 2 nd magnetic layer 12 in the Z-axis direction is changed in conjunction with the height HT of the 1 st magnetic layer 11. The normalized off-track magnetic field gradient is about-1.8X 10 at heights HT of 20nm, 40nm, 60nm, and 80nm-2And/nm. The normalized off-track magnetic field gradient is substantially independent of the height HT.
Hereinafter, in the 1 st model M1, an example of characteristics when the length L1 (see fig. 1(b)) of the 1 st magnetic layer 11 is changed will be described. At this time, the length of the 2 nd magnetic layer 12 is changed in conjunction with the length L1 of the 1 st magnetic layer 11. As already mentioned, the normalized off-track magnetic field gradient at a length L1 of 60nm is approximately-1.8X 10-2And/nm. The normalized off-track magnetic field gradient at a length L1 of 50nm is approximately-1.78X 10-2And/nm. Normalized off-track magnetic field gradient at 40nm of length L1is-1.7X 10-2And/nm. The normalized off-track magnetic field gradient at a length L1 of 30nm is approximately-1.6X 10-2And/nm. The normalized off-track magnetic field gradient at a length L1 of 20nm is approximately-1.49X 10-2And/nm. When the length L1 is long, the absolute value of the normalized off-track magnetic field gradient becomes large. In the embodiment, the length L1 is preferably 30nm or more, for example.
Hereinafter, an example of the operation of the magnetic head 110 according to the embodiment will be described. The 1 st layered product SB1 will be described below. The following description can be applied to the 2 nd stacked body SB2 by replacing the 1 st stacked body SB1 with the 2 nd stacked body SB2 and replacing the 2 nd shielding region 32 with the 3 rd shielding region 33.
Fig. 5 is a schematic diagram illustrating an operation of the magnetic head according to the embodiment.
As shown in fig. 5, the 1 st stacked body SB1 is provided between the magnetic pole 30 and the 2 nd shield region 32. In the 1 st stacked body SB1, the 1 st magnetic layer 11, the 1 st conductive layer 21, and the 2 nd conductive layer 22 are provided.
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 was applied to the 1 st stack SB 1.
For example, the magnetization 30M of the pole 30 and the magnetization 32M of the 2 nd shield region 32 are substantially parallel to the gap magnetic field Hg 1. The magnetization 11M of the 1 st magnetic layer 11 is substantially parallel to the gap magnetic field Hg 1.
At this time, the 1 st circuit 20D supplies the current Ic (corresponding to the 1 st current i1) to the 1 st stacked body SB 1. In this example, the current Ic is supplied to the 1 st stacked body SB1 via the 2 nd shield region 32 and the magnetic pole 30. The current Ic flows from, for example, the 2 nd conductive layer 22 to the 1 st conductive layer 21. At this time, the electron current Je flows. The electron current Je flows from the 1 st conductive layer 21 to the 2 nd conductive layer 22.
By the electron current Je, spin torque 21sp is generated at the interface between the 1 st conductive layer 21 and the 1 st magnetic layer 11. The spin torque 21sp is of a transmission type. On the other hand, a spin torque 22sp is generated at the interface between the 1 st magnetic layer 11 and the 2 nd conductive layer 22 by the electron current Je. Spin torque 22sp is a reflection type. By the above-described spin torque, the magnetization 11M of the 1 st magnetic layer 11 is inverted. The reversed magnetization 11M has a component opposite to the gap magnetic field Hg 1.
The current Ic may flow from the 1 st conductive layer 21 toward the 2 nd conductive layer 22, for example. At this time, the direction of spin torque 21sp and the direction of spin torque 22sp shown in fig. 5 are reversed. At this time, spin torque 21sp is a reflection type, and spin torque 22sp is a transmission type.
For example, by appropriately controlling the spin torque 21sp and the spin torque 22sp, the magnetization 11M of the 1 st magnetic layer 11 is easily inverted. The spin torque can be appropriately controlled by the above-described examples of the materials described for the 1 st conductive layer 21 and the 2 nd conductive layer 22.
(embodiment 2)
Embodiment 2 relates to a magnetic recording and reproducing apparatus. The magnetic recording and reproducing apparatus includes, for example, the magnetic head 110 (and a modified magnetic head thereof) described in relation to embodiment 1. The magnetic recording and reproducing device further includes a magnetic recording medium 80, and a1 st circuit 20D capable of supplying a current (a 1 st current i1) to the 1 st stacked body SB 1. In the case where the magnetic head 110 includes the 2 nd stack SB2, the 1 st circuit 20D may also supply a current (the 2 nd current i2) to the 2 nd stack SB 2.
Hereinafter, an example of the magnetic recording and reproducing apparatus according to the present embodiment will be described.
Fig. 6 is a schematic perspective view illustrating a part of the magnetic recording and reproducing device according to the embodiment.
FIG. 6 illustrates a head slider.
The magnetic head 110 is provided to a head slider 159. The head slider 159 contains, for example, Al2O3and/TiC, etc. The head slider 159 performs a relative motion with respect to the magnetic recording medium while floating on or in contact with 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, and the like. Thus, the magnetic head 110 performs relative motion with respect to the magnetic recording medium while floating on or contacting the magnetic recording medium.
Fig. 7 is a schematic perspective view illustrating a magnetic recording and reproducing apparatus according to an embodiment.
Fig. 8(a) and 8(b) are schematic perspective views illustrating a part of the magnetic recording and reproducing device according to the embodiment.
As shown in fig. 7, a rotary actuator is used in the magnetic recording and reproducing device 150 according to 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 apparatus 150 according to the present embodiment may include a plurality of recording medium disks 180. The magnetic recording and reproducing device 150 may also include a recording medium 181. The recording medium 181 is, for example, an SSD (Solid State Drive). For example, a nonvolatile memory such as a flash memory is used for the recording medium 181. For example, the magnetic recording and reproducing device 150 may be 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 according to 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 and the pressure generated on the medium opposing surface (ABS) of the head slider 159 are balanced. The distance between the medium-facing surface of the head slider 159 and the surface of the recording medium disk 180 becomes a predetermined amount of levitation. 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 includes, for example, a wire barrel portion. 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 opposing yokes. 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 on the recording medium disk 180.
Fig. 8(a) is an enlarged perspective view of the head stack assembly 160, illustrating a part of the magnetic recording and reproducing apparatus.
Fig. 8(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. 8(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 direction of extension of the carrier 161 is opposite to the direction of extension of the head gimbal assembly 158. The carrier 161 supports a coil 162 of the voice coil motor 156.
As shown in fig. 8(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 according to the embodiment.
