JP7424946B2 - Magnetic head and magnetic recording device - Google Patents

Description

Embodiments of the present invention relate to a magnetic head and a magnetic recording device.

Information is recorded on a magnetic storage medium such as an HDD (Hard Disk Drive) using a magnetic head. In magnetic heads and magnetic recording devices, it is desired to improve the recording density.

JP 2019-57337 Publication

Embodiments of the present invention provide a magnetic head and a magnetic recording device that can improve recording density.

According to embodiments of the invention, a magnetic recording device includes a magnetic head and an electrical circuit. The magnetic head includes a first magnetic pole, a second magnetic pole, and a laminate provided between the first magnetic pole and the second magnetic pole. The laminate includes a first nonmagnetic layer, a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole, and a first magnetic layer between the first magnetic layer and the second magnetic pole. a second non-magnetic layer provided between the first layer and the second magnetic pole; and a second non-magnetic layer provided between the second non-magnetic layer and the second magnetic pole. 2 magnetic layers, and a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole. The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more. The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. ,including. The first layer includes Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Contains at least one selected from the group consisting of Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack.

FIGS. 1(a) to 1(c) are schematic cross-sectional views illustrating the magnetic recording device according to the first embodiment. FIGS. 2A and 2B are schematic cross-sectional views illustrating a magnetic recording device according to a reference example. 3(a) to 3(c) are schematic cross-sectional views illustrating the magnetic recording device according to the first embodiment. FIG. 4 is a graph diagram illustrating the characteristics of the magnetic head according to the embodiment. FIG. 5 is a graph diagram illustrating the characteristics of the magnetic head according to the embodiment. FIG. 6 is a graph diagram illustrating the characteristics of the magnetic head. FIG. 7 is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment. FIGS. 8(a) to 8(c) are schematic cross-sectional views illustrating a magnetic recording device according to the second embodiment. FIG. 9 is a schematic cross-sectional view illustrating a magnetic recording device according to the second embodiment. FIG. 10 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment. FIG. 11 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. FIG. 12 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment. FIG. 13 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment. FIG. 14 is a schematic perspective view illustrating a magnetic recording device according to an embodiment. FIGS. 15A and 15B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Each embodiment 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 width of each part, the size ratio between parts, etc. are not necessarily the same as the reality. Even when the same part is shown, the dimensions and ratios may be shown differently depending on the drawing.
In the specification of this application and each figure, the same elements as those described above with respect to the existing figures are given the same reference numerals, and detailed explanations are omitted as appropriate.

(First embodiment)
FIGS. 1(a) to 1(c) are schematic cross-sectional views illustrating the magnetic recording device according to the first embodiment.
As shown in FIG. 1A, a magnetic recording device 210 according to the embodiment includes a magnetic head 110 and a magnetic recording medium 80. Information is recorded on the magnetic recording medium 80 by the magnetic head 110 . The magnetic recording medium 80 is, for example, a perpendicular recording medium. An example of the magnetic recording medium 80 will be described later.

As shown in FIG. 1A, the magnetic head 110 includes a first magnetic pole 30, a second magnetic pole 31, and a laminated body 20. The laminated body 20 is provided between the first magnetic pole 30 and the second magnetic pole 31.

In this example, the laminate 20 includes a first nonmagnetic layer 41 , a first magnetic layer 21 , a first layer 25 , a second nonmagnetic layer 42 , a second magnetic layer 22 , and a third nonmagnetic layer 43 . As described later, another magnetic layer (third magnetic layer) may be further provided.

The first magnetic layer 21 is provided between the first nonmagnetic layer 41 and the second magnetic pole 31. The first layer 25 is provided between the first magnetic layer 21 and the second magnetic pole 31. The second nonmagnetic layer 42 is provided between the first layer 25 and the second magnetic pole 31. The second magnetic layer 22 is provided between the second nonmagnetic layer 42 and the second magnetic pole 31. The third nonmagnetic layer 43 is provided between the second magnetic layer 22 and the second magnetic pole 31.

The first magnetic layer 21 includes at least one first element selected from the group consisting of Co, Fe, and Ni. The concentration of the first element in the first magnetic layer 21 is 50 atomic % or more. The first magnetic layer 21 includes, for example, a FeCo alloy or a NiFe alloy.

The second magnetic layer 22 includes at least one second element selected from the group consisting of Fe, Ni, and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti, and Sc. ,including.

For example, the material of the second magnetic layer 22 is different from the material of the first magnetic layer 21. For example, the characteristics of the second magnetic layer 22 are different from the characteristics of the first magnetic layer 21. For example, the properties of the second magnetic layer 22 are different from the properties of the first magnetic layer 21. For example, the polarization characteristics of the second magnetic layer 22 are different from the polarization characteristics of the first magnetic layer 21. For example, the first magnetic layer 21 has positive polarization. The second magnetic layer 22 has negative polarization.

The first layer 25 includes Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Contains at least one selected from the group consisting of Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu (hereinafter referred to as "first layer material group").

For example, the first nonmagnetic layer 41 includes at least one selected from the group consisting of Ta, Ru, Cr, and Cu. For example, the second nonmagnetic layer 42 includes at least one selected from the group consisting of Cu, Ag, Au, and Cr. The third nonmagnetic layer 43 includes at least one selected from the group consisting of Cu, Ag, and Au.

The first magnetic pole 30 is, for example, a main magnetic pole. The second magnetic pole 31 is, for example, a shield (for example, a trailing shield). The first magnetic pole 30 and the second magnetic pole 31 form a magnetic circuit, for example. As will be described later, a coil is provided at the first magnetic pole 30 (or/and second magnetic pole 31). A recording magnetic field is generated from the first magnetic pole 30 in accordance with the recording current flowing through the coil. At least a portion of the generated recording magnetic field is directed toward the magnetic recording medium 80. At least a portion of the recording magnetic field is applied to the magnetic recording medium 80. The magnetization direction of the portion of the magnetic recording medium 80 to which the recording magnetic field is applied is controlled by the recording magnetic field. As a result, information is recorded on the magnetic recording medium 80 according to the direction of the recording magnetic field. For example, at least a portion of the recording magnetic field is directed toward the second magnetic pole 31 after being directed toward the magnetic recording medium 80 .

The direction from the first magnetic pole 30 to the second magnetic pole 31 is defined as the X-axis direction. The X-axis direction is, for example, a downtrack direction.

A current can be supplied to the stack 20. For example, as will be described later, current is supplied to the stacked body 20 via the first magnetic pole 30 and the second magnetic pole 31. The current is supplied from an electric circuit 20D (see FIG. 12) which will be described later.

FIG. 1A corresponds to a state where no current is supplied to the stacked body 20 (third state ST3). FIG. 1(c) corresponds to the first state ST1. In the first state ST1, the first current i1 is supplied to the stacked body 20. FIG. 1(b) corresponds to the second state ST2. In the second state ST2, the second current i2 is supplied to the stacked body 20. The second current i2 is smaller than the first current i1. The first current i1 is supplied, for example, from an electric circuit 20D (see FIG. 12), which will be described later. In the examples shown in FIGS. 1(a) to 1(c), the magnetization of the first magnetic pole 30 and the second magnetic pole 31 are fixed in the X-axis direction by the current flowing through the coil. In this state, the second current i2 is supplied to the stacked body 20.

The first current i1 is, for example, a current sufficient to reverse the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22.

In this example, the first current i1 has a first direction D1 from the second magnetic pole 31 to the first magnetic pole 30. The second current i2 also has a first direction D1 from the second magnetic pole 31 to the first magnetic pole 30. By supplying the large first current i1 to the stacked body 20, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 are reversed.

When the first current i1 flows through the stacked body 20, the first electron current je1 flows through the stacked body 20. The direction of the first electron current je1 is opposite to the direction of the first current i1. When the second current i2 flows through the stacked body 20, a second electron current je2 flows through the stacked body 20. The direction of the second electron current je2 is opposite to the direction of the second current i2.

In the first state ST1, the first magnetization 21M and the second magnetization 22M have components opposite to the direction of the magnetization 30M of the first magnetic pole 30 and the direction of the magnetization 31M of the second magnetic pole 31. This makes it difficult for the recording magnetic field generated from the first magnetic pole 30 to pass through the first magnetic layer 21 and the second magnetic layer 22 (that is, the laminated body 20). This makes it easier for most of the recording magnetic field generated from the first magnetic pole 30 to be directed toward the magnetic recording medium 80. A recording magnetic field is efficiently applied to the magnetic recording medium 80.

For example, when the distance between the first magnetic pole 30 and the second magnetic pole 31 is shortened in order to increase the recording density, the recording magnetic field generated from the first magnetic pole 30 is directed to the second magnetic pole 31 instead of toward the magnetic recording medium 80. It becomes easier to enter. At this time, in the embodiment, by reversing the first magnetization 21M and the second magnetization 22M, even if the distance between the first magnetic pole 30 and the second magnetic pole 31 is short, the recording magnetic field is effectively Head to the recording medium 80. Even when the distance between the first magnetic pole 30 and the second magnetic pole 31 is short, the recording magnetic field can be effectively applied to the magnetic recording medium 80. Thereby, a magnetic head and a magnetic recording device that can improve recording density can be provided.

In embodiments, for example, the stack 20 does not generate an alternating magnetic field. Alternatively, the frequency of the alternating magnetic field generated from the stacked body 20 is higher than the magnetic resonance frequency of the magnetic recording medium.

On the other hand, there is a reference example of MAMR (Microwave Assisted Magnetic Recording). In this reference example, a high frequency magnetic field is generated from a laminate including a magnetic layer. This high frequency magnetic field is applied to a part of the magnetic recording medium 80, causing magnetic resonance in a part of the magnetic recording medium 80, and the direction of magnetization of the magnetic recording medium 80 tends to change. In this reference example, the frequency of the high frequency magnetic field generated from the laminate is equal to or lower than the magnetic resonance frequency of the magnetic recording medium 80. As a result, the direction of magnetization of the magnetic recording medium 80 tends to change due to the occurrence of magnetic resonance.

In contrast, in the embodiment, the stacked body 20 does not generate an alternating magnetic field. Alternatively, the frequency of the alternating magnetic field generated from the stacked body 20 is higher than the magnetic resonance frequency of the magnetic recording medium. In the embodiment, unlike MAMR, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 are reversed.

Examples of changes in magnetization in the embodiment will be described below.
As shown in FIG. 1(a), in the third state ST3 (initial state) where no current is supplied, the magnetization 30M, the first magnetization 21M, the second magnetization 22M, and the magnetization 31M are in the same direction (for example, in the second direction D2).

As shown in FIG. 1(b), in the second state ST2 in which a small second current i2 (second electron current je2) is supplied to the stacked body 20, the second magnetization 22M of the second magnetic layer 22 is It is affected by the spin transfer torque STT3 from the magnetic pole 31 to the second magnetic layer 22. On the other hand, for example, since the first layer 25 is provided, the spin transfer torque STT1 from the first magnetic layer 21 is attenuated in the first layer 25, and the influence of the spin transfer torque STT1 on the second magnetic layer 22 is reduced. suppressed. As a result, the second magnetization 22M begins to change from its initial state. On the other hand, the first magnetization 21M of the first magnetic layer 21 remains in its initial state.

As shown in FIG. 1(c), in the first state ST1 in which a sufficiently large first current i1 (first electron current je1) is supplied to the stacked body 20, the spin transfer torque STT3 from the second magnetic pole 31 is Under the influence, the second magnetization 22M of the second magnetic layer 22 is different from the magnetization 30M of the first magnetic pole 30 and the magnetization 31M of the second magnetic pole 31 in the first state ST1, for example. It rotates in the opposite direction, and the component of the second magnetization 22M in the first direction D1 increases. In one example, the second magnetization 22M is reversed from its initial state. When the rotation angle of the second magnetization 22M exceeds 90 degrees, the first magnetization 21M of the first magnetic layer 21 is reversed under the influence of the spin transfer torque STT2 from the second magnetic layer 22. In this way, by flowing the large first current i1, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 are reversed from their initial states.

The reversal of the first magnetization 21M and the second magnetization 22M due to the spin transfer torque occurs in a short time of nanoseconds or less, following the reversal of the first magnetic pole. Therefore, even when recording a fine recording pattern with a short distance between the first magnetic pole 30 and the second magnetic pole 31, the recording magnetic field can be stably and effectively directed toward the magnetic recording medium 80. A magnetic head and a magnetic recording device that can improve recording density can be provided.

Hereinafter, an example of a change in magnetization in a reference example will be described.
FIGS. 2A and 2B are schematic cross-sectional views illustrating a magnetic recording device according to a reference example.
As shown in FIGS. 2A and 2B, the first layer 25 is not provided in the magnetic head 119 according to the reference example. FIG. 2A illustrates a case where the first magnetic layer 21 included in the magnetic head 119 has positive polarization. FIG. 2B illustrates a case where the first magnetic layer 21 included in the magnetic head 119 has negative polarization.

As shown in FIG. 2(a), in a second state ST2 in which a small second current i2 (second electron current je2) flows through the stacked body 20, the spin transfer torque STT3 from the second magnetic pole 31 and the first magnetic layer Both the spin transfer torque STT1 from 21 acts on the second magnetic layer 22. Since the polarity of the polarization of the first magnetic layer 21 that provides spin torque and the polarity of the polarization of the second magnetic pole 31 are positive, the direction of the spin transfer torque STT3 and the direction of the spin transfer torque STT1 from the first magnetic layer 21 are Since the directions are opposite to each other, they cancel each other out. Therefore, the second magnetization 22M of the second magnetic layer 22 is difficult to reverse.

When the polarity of the first magnetic layer 21 is negative, the polarity of the polarization of the first magnetic layer 21 is opposite to that of the second magnetic pole 31, so the spin transfer torque to the second magnetic layer 22 is This results in addition, and the reversal of the second magnetic layer 22 is accelerated. However, as shown in FIG. 2(b), in the first state ST1 in which a large first current i1 (first electron current je1) is supplied to the stacked body 20, the rotation angle of the magnetization 22M of the second magnetic layer 22 is Since the angle exceeds 90 degrees, the direction of the spin transfer torque STT2 from the second magnetic layer 22 is reversed, and the magnetization 21M of the first magnetic layer 21 is reversed. As a result, the spin transfer torque STT3 from the second magnetic pole 31 and the spin transfer torque STT1 from the first magnetic layer 21 are opposite to each other. In this way, in this reference example, it becomes difficult to reverse the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22, regardless of the polarization of the first magnetic layer 21. . In the reference example, a high current density is required that makes it difficult to ensure reliability.

In contrast, in the magnetic head 110 according to the embodiment, the disturbance of the spin transfer torque STT2 from the second magnetic layer 22 is suppressed. Reversal of the first magnetization 21M and the second magnetization 22M occurs at low current density. Thereby, a magnetic head and a magnetic recording device that can improve recording density can be provided.

As shown in FIG. 1(c), in the embodiment, when the first current i1 is supplied to the stacked body 20, for example, the first magnetization 21M of the first magnetic layer 21 has a component in the first direction D1. have When the first current i1 is supplied to the stacked body 20, the second magnetization 22M of the second magnetic layer 22 has a component in the first direction D1.

As shown in FIG. 1(b), when the second current i2 in the first direction D1 is supplied to the laminated body 20, the first magnetization 21M changes in the second direction from the first magnetic pole 30 to the second magnetic pole 31. It has a component of D2. This second current i2 is smaller than the first current i1. When the second current i2 is supplied to the stacked body 20, the second magnetization 22M has a component in the second direction D2. The component of the second magnetization 22M in the second direction D2 is smaller than the component of the first magnetization 21M in the second direction D2.

3(a) to 3(c) are schematic cross-sectional views illustrating the magnetic recording device according to the first embodiment.
As shown in FIGS. 3(a) to 3(c), the direction of the magnetization 30M of the first magnetic pole 30 and the direction of the magnetization 31M of the second magnetic pole 31 change in one period from FIGS. 1(a) to 3(c). This is the opposite of the situation illustrated in 1(c).

As shown in FIG. 3(c), the magnetization 30M of the first magnetic pole 30 has a component in the first direction D1. When the first current i1 is supplied to the stacked body 20, the first magnetization 21M of the first magnetic layer 21 has a component in the second direction D2. When the first current i1 is supplied to the stacked body 20, the second magnetization 22M of the second magnetic layer 22 has a component in the second direction D2.

As shown in FIGS. 3(a) and 3(b), when the current is not supplied to the laminated body 20 or when the second current i2 is supplied to the laminated body 20, the first magnetization 21M is It has a component in one direction D1. When no current is supplied to the stacked body 20 or when the second current i2 is supplied to the stacked body 20, the second magnetization 22M has a component in the first direction D1. In this way, even when the direction of the magnetization 30M of the first magnetic pole 30 is opposite to the states illustrated in FIGS. 1(a) to 1(c), the first state in which a large first current i1 is supplied is maintained. In ST1, the first magnetization 21M and the second magnetization 22M are reversed from the initial state (third state ST3).

Examples of characteristics of the magnetic head according to the embodiment will be described below.
FIG. 4 is a graph diagram illustrating the characteristics of the magnetic head according to the embodiment.
FIG. 4 illustrates simulation results of the characteristics of the magnetic head 110. The horizontal axis in FIG. 4 is the current density J20 flowing through the stacked body 20. The vertical axis in FIG. 4 is the parameter M1. The parameter M1 is a component of the sum of the magnetic thickness of the first magnetic layer 21 and the magnetic thickness of the second magnetic layer 22 in the first direction D1. The magnetic thickness of the first magnetic layer 21 is the product of the thickness (length along the X-axis direction) of the first magnetic layer 21 and the saturation magnetization of the first magnetic layer 21. The magnetic thickness of the second magnetic layer 22 is the product of the thickness (length along the X-axis direction) of the second magnetic layer 22 and the saturation magnetization of the second magnetic layer 22.

In this simulation model, the magnetic thickness of the first magnetic layer 21 is 4 nmT. The magnetic thickness of the second magnetic layer 22 is 4 nmT. The magnetic field (gap magnetic field) between the first magnetic pole 30 and the second magnetic pole 31 is 15 kOe. The first layer 25 reduces the spin transfer torque STT1 from the first magnetic layer 21 to the second magnetic layer 22, which is zero in this example. The time of the current supplied to the stacked body 20 is a sufficiently long time of 1 nanosecond or more.

As shown in FIG. 4, when the current density J20 is low (eg, 1×10 ⁸ A/cm ² or less), the parameter M1 is negative. When current density J20 increases, parameter M1 becomes positive. When the current density J20 is high (for example, 2×10 ⁸ A/cm ² or more), the parameter M1 is positive. When the current density J20 is in the range of 1×10 ⁸ A/cm ² to 2×10 ⁸ A/cm ² , the polarity of the parameter M1 is reversed. The reversal of the polarity of the parameter M1 corresponds to the magnetization of the stacked body 20 changing from the same direction as the magnetization 30M of the first magnetic pole 30 to the direction opposite to the magnetization 30M of the first magnetic pole 30.

When the current density J20 is 0, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 are in the same direction as the magnetization 30M of the first magnetic pole 30, and the parameter M1 is approximately -8 nmT. It is. When the current density J20 is 2×10 ⁸ A/cm ² or more, the parameter M1 becomes about 7 nmT and is saturated.

The magnetization of the stacked body 20 can be substantially reversed to the direction opposite to the magnetization 30M of the first magnetic pole 30. In accordance with this change, the effect of the laminate 20 on the recording magnetic field on the magnetic recording medium 80 changes from negative to positive, increasing the recording capacity.

FIG. 5 is a graph diagram illustrating the characteristics of the magnetic head according to the embodiment.
FIG. 5 corresponds to a characteristic obtained by converting the relationship between the current density J20 and the parameter M1 (magnetization direction of the laminate 20) illustrated in FIG. 4 into the relationship between the current density J20 and the electrical resistance R1. The horizontal axis in FIG. 5 is the current density J20. The vertical axis in FIG. 5 is electrical resistance R1.

As shown in FIG. 5, regarding the current density J20, there are a first range JR1, a second range JR2, and a third range JR3. The current density J20 in the second range JR2 is higher than the current density J20 in the first range JR1. The current density J20 in the third range JR3 is higher than the current density J20 in the second range JR2. In each of the first range JR1 and the third range JR3, when the current density J20 increases, the electrical resistance R1 increases parabolically. This is the effect of heat generation. In the second range JR2, as the current density J20 increases, the electrical resistance R1 decreases. The decrease in electrical resistance R1 is due to the negative magnetoresistive effect that occurs between the second magnetic layer 22 with negative polarization and the second magnetic pole 31 with positive polarization. The decrease in the electrical resistance R1 corresponds to the reversal of the second magnetization 22M of the second magnetic layer 22.

As can be seen from FIG. 5, the rate of change (slope) of the electrical resistance R1 with respect to the change in the current density J20 is positive when the current density J20 is within the first range JR1. The rate of change is negative when the current density J20 is in the second range JR2. The rate of change is positive when the current density J20 is in the third range JR3. The second range JR2 is between the first range JR1 and the third range JR3.

The first range JR1 corresponds to the second state ST2 illustrated in FIG. 1(b). The third range JR3 corresponds to, for example, the first state ST1 illustrated in FIG. 1(c). The first magnetization 21M of the first magnetic layer 21 and the magnetization 22M of the second magnetic layer 22 are reversed when the current density J20 is in the second range JR2.

For example, when the current density J20 is in the first range JR1, the first magnetization 21M of the first magnetic layer 21 and the magnetization 22M of the second magnetic layer 22 have components in the direction of the magnetization 30M of the first magnetic pole 30. For example, when the current density J20 is in the third range JR3, the first magnetization 21M of the first magnetic layer 21 and the magnetization 22M of the second magnetic layer 22 are reversed, and are opposite to the direction of the magnetization 30M of the first magnetic pole 30. It has the following ingredients.

The electric circuit 20D (see FIG. 12) supplies the stacked body 20 with a first current i1 having a current density J20 within the third range JR3. As a result, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 have components opposite to the direction of the magnetization 30M of the first magnetic pole 30. This makes it easier for the recording magnetic field from the first magnetic pole 30 to be directed toward the magnetic recording medium 80. Thereby, the recording magnetic field is efficiently applied to the magnetic recording medium 80. A magnetic head and a magnetic recording device that can improve recording density can be provided.

The current density corresponding to the first current i1 above corresponds to the current density J20 within the third range JR3. The current density corresponding to the above second current i2 corresponds to the current density J20 within the first range JR1.

In the magnetic head 110, for example, the first layer 25 is in contact with the first magnetic layer 21 and the second nonmagnetic layer 42. For example, the second nonmagnetic layer 42 is in contact with the first layer 25 and the second magnetic layer 22.

FIG. 6 is a graph diagram illustrating the characteristics of the magnetic head.
FIG. 6 illustrates simulation results of the dynamic characteristics of the magnetic head.

The horizontal axis in FIG. 6 is time tm. Immediately after the magnetization 30M of the first magnetic pole 30 and the magnetization 31M of the second magnetic pole 31 are reversed, the time tm is zero. The vertical axis in FIG. 6 is the above parameter M1. In FIG. 6, the current density J20 is 2×10 ⁸ A/cm ² .

FIG. 6 illustrates the characteristics of the magnetic head 110, the characteristics of the magnetic head 119a, and the characteristics of the magnetic head 119b according to the embodiment.

In the magnetic head 110, the magnetic thickness of the first magnetic layer 21 is 4 nmT. The magnetic thickness of the second magnetic layer 22 is 6 nmT. The magnetic field (gap magnetic field) between the first magnetic pole 30 and the second magnetic pole 31 is 15 kOe. The value of the spin transfer torque STT3 corresponds to the value when positively polarized FeCo is used as the second magnetic pole 31.

The first layer 25 is not provided in the magnetic head 119a. In the magnetic head 119a, the spin transfer torque STT1 from the first magnetic layer 21 to the second magnetic layer 22 has the same value as the spin transfer torque STT3 from the second magnetic pole 31 to the second magnetic layer 22. The magnetic thickness of the first magnetic layer 21 and the second magnetic layer 22 in the magnetic head 119a are the same as the magnetic thickness of the first magnetic layer 21 and the second magnetic layer 22 in the magnetic head 110, respectively. . Except for this, the conditions for magnetic head 119a are the same as those for magnetic head 110.

In the stacked body 20 of the magnetic head 119b, the first magnetic layer 21, the first layer 25, and the second nonmagnetic layer 42 are not provided. In the magnetic head 119b, a first nonmagnetic layer 41 and a second magnetic layer 22 are provided. The magnetic thickness of the second magnetic layer 22 in the magnetic head 119b is 10 nmT. The magnetic thickness of the second magnetic layer 22 in the magnetic head 119b is the same as the total magnetic thickness of the first magnetic layer 21 and the second magnetic layer 22 in the magnetic heads 110 and 119a. Except for this, the conditions for magnetic head 119b are the same as those for magnetic head 110. In the magnetic head 119b, the magnetization 22M of the second magnetic layer 22 is reversed by the spin transfer torque STT3 from the second magnetic pole 31.

As shown in FIG. 6, the time tm in which the parameter M1 changes from negative to positive in the magnetic head 110 is shorter than the time tm in which the parameter M1 changes from negative to positive in the magnetic head 119a. The time tm in which the parameter M1 changes from negative to positive in the magnetic head 110 is shorter than the time tm in which the parameter M1 changes from negative to positive in the magnetic head 119b. In the magnetic head 110, magnetization reversal with a large magnetic thickness can be obtained in a short time. In embodiments, a large magnetic thickness can be reversed at high speed, thereby improving the BER (bit error rate).

FIG. 7 is a schematic cross-sectional view illustrating the magnetic recording device according to the first embodiment.
A magnetic recording device 210 according to the embodiment includes a magnetic head 111 shown in FIG. 7 and a magnetic recording medium 80 (see FIG. 1(a)). In the magnetic head 111, the laminate 20 includes, in addition to the first nonmagnetic layer 41, the first magnetic layer 21, the first layer 25, the second nonmagnetic layer 42, the second magnetic layer 22, and the third nonmagnetic layer 43. , the third magnetic layer 23 may be included.

The third magnetic layer 23 is provided between the third nonmagnetic layer 43 and the second magnetic pole 31. The third magnetic layer 23 contains at least one fourth element selected from the group consisting of Co, Fe, and Ni. The concentration of the fourth element in the third magnetic layer 23 is 50 atomic % or more. The third magnetic layer 23 has, for example, positive polarization.

When the third magnetic layer 23 is provided, the spin transfer torque STT3 explained with respect to FIG. 1(b), FIG. 1(c), FIG. 3(b), and FIG. It is supplied to the second magnetic layer 22. For example, the third magnetic layer 23 has a function of supplying spin transfer torque to the second magnetic pole 31.

Even when the third magnetic layer 23 is provided, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 can be stably and efficiently reversed.

As shown in FIG. 7, the first nonmagnetic layer 41, the first magnetic layer 21, the first layer 25, the second nonmagnetic layer 42, the second magnetic layer 22, the third nonmagnetic layer 43, and the third magnetic layer 23 have a thickness t41, a thickness t21, a thickness t25, a thickness t42, a thickness t22, a thickness t43, and a thickness t23, respectively. These thicknesses are lengths along the stacking direction (for example, the X-axis direction) of the stacked body 20.

In the magnetic heads 110 and 111, the thickness t41 of the first nonmagnetic layer 41 is preferably, for example, 1 nm or more and 6 nm or less. By setting the thickness t41 to 1 nm or more, exchange coupling between the first magnetic pole 30 and the first magnetic layer 21 can be suppressed. Thereby, the first magnetization 21M of the first magnetic layer 21 is easily reversed. By setting the thickness t41 to 6 nm or less, it is possible to prevent the distance Lg (recording gap) between the first magnetic pole 30 and the second magnetic pole 31 from becoming excessively long.

In the magnetic heads 110 and 111, the thickness t42 of the second nonmagnetic layer 42 is preferably, for example, 1 nm or more and 4 nm or less. By setting the thickness t42 to 1 nm or more, exchange coupling between the first magnetic layer 21 and the second magnetic layer 22 can be suppressed. Thereby, the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22 are easily reversed. By setting the thickness t42 to 4 nm or less, it is possible to prevent the distance Lg (recording gap) from becoming excessively long.

In the magnetic heads 110 and 111, the thickness t43 of the third nonmagnetic layer 43 is preferably, for example, 1 nm or more and 4 nm or less. When the thickness t43 is 1 nm or more, exchange coupling between the second magnetic layer 22 and the third magnetic layer 23 (or the second magnetic layer 22 and the second magnetic pole 31) can be suppressed. Thereby, the second magnetization 22M of the second magnetic layer 22 is easily reversed. By setting the thickness t43 to 4 nm or less, it is possible to prevent the distance Lg (recording gap) from becoming excessively long.

In the magnetic heads 110 and 111, the product (magnetic thickness) of the saturation magnetization Ms of the first magnetic layer 21 and the thickness t21 of the first magnetic layer 21 is preferably 1 nmT or more and 6 nmT or less. When the magnetic thickness is 1 nmT or more, the bit error rate (BER) is effectively improved. When the magnetic thickness is 6 nmT or less, high-speed magnetization reversal can be obtained, for example, at a practical current density J20 that ensures reliability. BER can be improved.

In the magnetic heads 110 and 111, the product (magnetic thickness) of the saturation magnetization Ms of the second magnetic layer 22 and the thickness t22 of the second magnetic layer 22 is preferably 1 nmT or more and 9 nmT or less. When the magnetic thickness is 1 nmT or more, the bit error rate (BER) is effectively improved. By setting the magnetic thickness to 9 nmT or less, for example, formation of magnetic domains can be suppressed. Reversal of the second magnetization 22M becomes easy. When the magnetic thickness is 9 nm or less, formation of magnetic domains can be suppressed. High-speed magnetization reversal can be obtained by using a practical current density J20 that can ensure reliability. BER can be improved.

For example, it is preferable that the magnetic thickness of the second magnetic layer 22 is substantially the same as the magnetic thickness of the first magnetic layer 21 or larger than the magnetic thickness of the first magnetic layer 21 . For example, the magnetic thickness of the second magnetic layer 22 is at least 0.8 times and at most 3 times the magnetic thickness of the first magnetic layer 21 . For example, the ratio of the magnetic thickness of the first magnetic layer 21 to the magnetic thickness of the second magnetic layer 22 is 2 nmT/6 nmT, 4 nmT/4 nmT, or 4 nmT/6 nmT. Thereby, for example, high-speed magnetization reversal can be obtained in the first magnetization 21M of the first magnetic layer 21 and the second magnetization 22M of the second magnetic layer 22.

In the magnetic heads 110 and 111, the thickness t25 of the first layer 25 is preferably greater than 0 nm and less than 3 nm, for example. Since the thickness t25 is 3 nm or less, the spin transfer torque STT2 from the second magnetic layer 22 effectively acts on the first magnetic layer 21. This facilitates reversal of the first magnetization 21M of the first magnetic layer 21.

In the magnetic head 111, it is preferable that the thickness t23 of the third magnetic layer 23 is, for example, more than 0 nm and less than 2 nm. By setting the thickness t23 to 2 nm or less, it is possible to prevent the distance Lg (recording gap) from becoming excessively long. The third magnetic layer 23 may be omitted. At least a portion of the third magnetic layer 23 may be considered to be included in the second magnetic pole 31.

(Second embodiment)
FIGS. 8(a) to 8(c) are schematic cross-sectional views illustrating a magnetic recording device according to the second embodiment.
As shown in FIG. 8A, a magnetic recording device 210 according to the embodiment includes a magnetic head 120 and a magnetic recording medium 80. The magnetic head 120 includes a first magnetic pole 30, a second magnetic pole 31, and a laminated body 20. In the second embodiment, the laminate 20 includes a first nonmagnetic layer 41 , a first magnetic layer 21 , a second nonmagnetic layer 42 , a second magnetic layer 22 , and a third nonmagnetic layer 43 . The first magnetic layer 21 is provided between the first nonmagnetic layer 41 and the second magnetic pole 31. The second nonmagnetic layer 42 is provided between the first magnetic layer 21 and the second magnetic pole 31. The second magnetic layer 22 is provided between the second nonmagnetic layer 42 and the second magnetic pole 31. The third nonmagnetic layer 43 is provided between the second magnetic layer 22 and the second magnetic pole 31. In the magnetic head 120, the first layer 25 is not provided. For example, the second nonmagnetic layer 42 is in contact with the first magnetic layer 21 and the second magnetic layer 22.

In the magnetic head 120, the first magnetic layer 21 includes at least one first element selected from the group consisting of Co, Fe, and Ni. The concentration of the first element in the first magnetic layer 21 is 50 atomic % or more. The second magnetic layer 22 includes at least one second element selected from the group consisting of Fe, Ni, and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti, and Sc. ,including. The first magnetic layer 21 does not contain the third element. Alternatively, the concentration of the third element in the first magnetic layer 21 is lower than the concentration of the third element in the second magnetic layer 22.

For example, the second magnetic layer 22 has negative polarization. The first magnetic layer 21 has no polarization. Alternatively, the polarization magnitude (absolute value) of the first magnetic layer 21 is smaller than the polarization magnitude (absolute value) of the second magnetic layer 22 . In this way, the first magnetic layer 21 and the second magnetic layer 22 have asymmetric characteristics.

For example, if the Cr concentration of the FeCr alloy in the first magnetic layer 21 is about 10%, the polarization of the first magnetic layer 21 will be close to zero. For example, in the second magnetic layer 22, the concentration (composition ratio) of Cr in the FeCr alloy is 30 atomic % or more and 40 atomic % or less. As a result, the polarization of the second magnetic layer 22 has a large absolute value and becomes negative. For example, by including Cr in the portion of the second nonmagnetic layer 42 that is in contact with the second magnetic layer 22, negative polarization with a large absolute value can be obtained in the second magnetic layer 22.

For example, the composition of the FeCr alloy contained in the first magnetic layer 21 may be substantially the same as the composition of the FeCr alloy contained in the second magnetic layer 22. For example, if the composition of the FeCr alloy included in the first magnetic layer 21 is different from the composition of the FeCr alloy included in the negatively polarized second magnetic layer 22, the number of sputtering targets increases. For example, the first magnetic layer 21 may be polarized by including a laminated film including a positively polarized FeCo alloy film and a negatively polarized FeCr alloy film having the same composition as the second magnetic layer 22. can be close to zero.

In the magnetic head 120 as well, the electric circuit supplies the first current i1 having the first direction D1 from the second magnetic pole 31 to the first magnetic pole 30 to the stacked body 20. As a result, the first magnetization 21M and the second magnetization of the first magnetic layer 21, similar to the above explanation regarding FIGS. The second magnetization 22M of layer 22 is reversed. The first magnetization 21M and the second magnetization 22M have components opposite to the direction of the magnetization 30M of the first magnetic pole 30. The recording magnetic field from the first magnetic pole 30 is more likely to be directed toward the magnetic recording medium 80. A recording magnetic field is efficiently applied to the magnetic recording medium 80. A magnetic head and a magnetic recording device that can improve recording density can be provided.

In the magnetic head 120, the materials of the first nonmagnetic layer 41, the first magnetic layer 21, the second nonmagnetic layer 42, the second magnetic layer 22, and the third nonmagnetic layer 43 described with respect to the magnetic head 110 and the magnetic head 111 Configurations such as thickness and thickness can be applied.

The second nonmagnetic layer 42 may include a laminated film including a Cu film and a Cr film. For example, a Cr film is provided on the interface side of the second magnetic layer 22 of the second nonmagnetic layer 42, and the second magnetic layer 22 and the Cr film are in contact with each other. This improves the negative polarization of the second magnetic layer 22 and facilitates magnetization reversal of the first magnetic layer 21.

FIG. 9 is a schematic cross-sectional view illustrating a magnetic recording device according to the second embodiment.
FIG. 9 shows a part of the stacked body 20 as an example. As shown in FIG. 9, the first magnetic layer 21 includes a first film 21a and a second film 21b. The second film 21b is located at either a first position between the first nonmagnetic layer 41 and the first film 21a or a second position between the first film 21a and the second nonmagnetic layer 42. . In the example of FIG. 9, the second film 21b is between the first film 21a and the second nonmagnetic layer 42. Also in this example, the second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni, and Co, and at least one second element selected from the group consisting of Cr, V, Mn, Ti, and Sc. and a third element.

The first film 21a includes the second element described above and the third element described above. In the first example, the second film 21b does not contain the third element. In the second example, the concentration of the third element in the second film 21b is lower than the concentration of the third element in the first film 21a. A configuration in which a positively polarized magnetic film and a negatively polarized magnetic film are laminated reduces the polarization of the first magnetic layer 21 and reduces the spin transfer torque STT1 to the first magnetic layer 21. Can be done. For example, the composition of the first film is substantially the same as the composition of the second magnetic layer.

Examples of magnetic heads and magnetic recording media according to embodiments will be described below.
FIG. 10 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment.
As shown in FIG. 10, in the magnetic head 112 according to the embodiment, the first direction D1 from the second magnetic pole 31 to the first magnetic pole 30 may be inclined with respect to the X-axis direction. The first direction D1 (or the second direction D2) corresponds to the stacking direction of the stacked body 20. The X-axis direction is along the medium facing surface 30F of the first magnetic pole 30. The angle between the first direction D1 and the medium facing surface 30F is defined as an angle θ1. The angle θ1 is, for example, 15 degrees or more and 30 degrees or less. The angle θ1 may be 0 degrees.

When the first direction D1 is inclined with respect to the X-axis direction, the thickness of the layer (for example, the thickness t21, etc.) corresponds to the length along the first direction D1. The configuration in which the first direction D1 is inclined with respect to the X-axis direction may be applied to any magnetic head according to the first embodiment or the second embodiment.

Examples of magnetic heads and magnetic recording media according to embodiments will be described below. An example of the magnetic head 110 will be described below.

FIG. 11 is a schematic perspective view illustrating a magnetic recording device according to an embodiment.
FIG. 12 is a schematic cross-sectional view illustrating the magnetic head according to the embodiment.
As shown in FIG. 11, a magnetic head 110 according to the embodiment is used together with a magnetic recording medium 80. The magnetic recording device 210 according to the embodiment includes a magnetic head 110 and a magnetic recording medium 80. In this example, the magnetic head 110 includes a recording section 60 and a reproducing section 70. Information is recorded on the magnetic recording medium 80 by the recording unit 60 of the magnetic head 110 . The reproduction section 70 reproduces information recorded on the magnetic recording medium 80.

The magnetic recording medium 80 includes, for example, a medium substrate 82 and a magnetic recording layer 81 provided on the medium substrate 82. Magnetization 83 of the magnetic recording layer 81 is controlled by the recording section 60.

The reproducing section 70 includes, for example, a first reproducing magnetic shield 72a, a second reproducing magnetic shield 72b, and a magnetic reproducing element 71. The magnetic reproducing element 71 is provided between the first reproducing magnetic shield 72a and the second reproducing magnetic shield 72b. The magnetic reproducing element 71 can output a signal according to the magnetization 83 of the magnetic recording layer 81.

As shown in FIG. 11, the magnetic recording medium 80 moves relative to the magnetic head 110 in a medium movement direction 85. The magnetic head 110 controls information corresponding to the magnetization 83 of the magnetic recording layer 81 at an arbitrary position. The magnetic head 110 reproduces information corresponding to the magnetization 83 of the magnetic recording layer 81 at an arbitrary position.

As shown in FIG. 12, the magnetic head 110 is provided with a coil 30c. A recording current Iw is supplied from the recording circuit 30D to the coil 30c. A recording magnetic field corresponding to the recording current Iw is applied to the magnetic recording medium 80 from the first magnetic pole 30 .

As shown in FIG. 12, the first magnetic pole 30 includes a medium facing surface 30F. The medium facing surface 30F is, for example, an ABS (Air Bearing Surface). The medium facing surface 30F faces the magnetic recording medium 80, for example.

The direction perpendicular to the medium facing surface 30F is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The direction perpendicular to the Z-axis direction and the X-axis direction is defined as the Y-axis direction.

The Z-axis direction is, for example, the height direction. The X-axis direction is, for example, a downtrack direction. The Y-axis direction is, for example, a cross-track direction.

As shown in FIG. 12, an electric circuit 20D is electrically connected to the laminate 20. In this example, the stacked body 20 is electrically connected to the first magnetic pole 30 and the second magnetic pole 31. The magnetic head 110 is provided with a first terminal T1 and a second terminal T2. The first terminal T1 is electrically connected to the stacked body 20 via the wiring W1 and the first magnetic pole 30. The second terminal T2 is electrically connected to the stacked body 20 via the wiring W2 and the second magnetic pole 31. For example, current (for example, direct current) is supplied to the stacked body 20 from the electric circuit 20D.

As shown in FIG. 12, a shield 32 may be provided in the recording section 60. A first magnetic pole 30 is provided between the shield 32 and the second magnetic pole 31. An insulating section 30i is provided around the second magnetic pole 31, the second magnetic pole 31, and the first magnetic pole 30.

The magnetic recording device 210 according to the embodiment includes a magnetic head 110 and a magnetic recording medium 80 on which information is recorded by the magnetic head 110. An example of a magnetic recording device according to an embodiment will be described below. The magnetic recording device may be a magnetic recording/reproducing device. The magnetic head may include a recording section and a reproducing section.

FIG. 13 is a schematic perspective view illustrating a part of the magnetic recording device according to the embodiment.
FIG. 13 illustrates a head slider.
The magnetic head 110 is provided on a head slider 159. The head slider 159 includes, for example, Al ₂ O ₃ /TiC. The head slider 159 moves relative to the magnetic recording medium while flying over 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 arranged on the side surface of the air outflow 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 the magnetic recording medium.

FIG. 14 is a schematic perspective view illustrating a magnetic recording device according to an embodiment.
FIGS. 15A and 15B are schematic perspective views illustrating a part of the magnetic recording device according to the embodiment.
As shown in FIG. 14, a rotary actuator is used in the magnetic recording device 150 according to the embodiment. The recording medium disk 180 is mounted on a spindle motor 180M. The recording medium disk 180 is rotated in the direction of arrow AR by a spindle motor 180M. Spindle motor 180M is responsive to control signals from the drive controller. The magnetic recording device 150 according to this embodiment may include a plurality of recording medium disks 180. The magnetic recording device 150 may 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 as the recording medium 181. For example, the magnetic recording device 150 may be a hybrid HDD (Hard Disk Drive).

The head slider 159 records and reproduces information to be recorded on the recording medium disk 180. The head slider 159 is provided at the tip of the thin film suspension 154. A 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 pressure by the suspension 154 and the pressure generated at the medium facing 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 flying height. In embodiments, the head slider 159 may contact the recording medium disk 180. For example, a contact running type may be applied.

Suspension 154 is connected to one end of arm 155 (eg, an actuator arm). The arm 155 includes, for example, a bobbin portion. The bobbin section holds the drive coil. A voice coil motor 156 is provided at the other end of the arm 155. Voice coil motor 156 is a type of linear motor. Voice coil motor 156 includes, for example, a drive 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. Suspension 154 has one end and the other end. A magnetic head is provided at one end of the suspension 154. Arm 155 is connected to the other end of suspension 154.

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 be rotated and slid by a voice coil motor 156. The magnetic head can be moved to any position on the recording medium disk 180.

FIG. 15A is an enlarged perspective view of a head stack assembly 160, illustrating a part of the configuration of the magnetic recording device.
FIG. 15B is a perspective view illustrating a magnetic head assembly (head gimbal assembly: HGA) 158 that is part of the head stack assembly 160.

As shown in FIG. 15(a), the head stack assembly 160 includes a bearing portion 157, a head gimbal assembly 158, and a support frame 161. A head gimbal assembly 158 extends from bearing portion 157. Support frame 161 extends from bearing portion 157 . The direction in which the support frame 161 extends is opposite to the direction in which the head gimbal assembly 158 extends. Support frame 161 supports coil 162 of voice coil motor 156.

As shown in FIG. 15(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.

A head slider 159 is provided at the tip of the suspension 154. The head slider 159 is provided with the magnetic head according to the embodiment.

A magnetic head assembly (head gimbal assembly) 158 according to the embodiment includes the magnetic head according to the embodiment, a head slider 159 provided with the magnetic head, a suspension 154, and an arm 155. Head slider 159 is provided at one end of suspension 154. Arm 155 is connected to the other end of suspension 154.

The suspension 154 has, for example, lead wires (not shown) for recording and reproducing signals. The suspension 154 may have, for example, a heater lead wire (not shown) for adjusting the flying height. The suspension 154 may have lead wires (not shown) for, for example, a spin transfer torque oscillator. These lead wires and a plurality of electrodes provided on the magnetic head are electrically connected.

In the magnetic recording device 150, a signal processing section 190 is provided. The signal processing unit 190 uses a magnetic head to record and reproduce signals on a magnetic recording medium. The input/output line of the signal processing section 190 is connected to, for example, an electrode pad of the head gimbal assembly 158, and is electrically connected to the magnetic head.

The magnetic recording device 150 according to the embodiment includes a magnetic recording medium, a magnetic head according to the embodiment, a movable section, a position control section, and a signal processing section. The movable part allows the magnetic recording medium and the magnetic head to move relative to each other while being separated from each other or in a state in which they are in contact with each other. The position control unit positions the magnetic head at a predetermined recording position on the magnetic recording medium. The signal processing section records and reproduces signals on and from a magnetic recording medium using a magnetic head.

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

Embodiments may include the following configurations (eg, technical proposals).
(Configuration 1)
magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first layer includes Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Contains at least one selected from the group consisting of Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu,
The electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack.

(Configuration 2)
The magnetic recording device according to Configuration 1, wherein the first layer is in contact with the first magnetic layer and the second nonmagnetic layer.

(Configuration 3)
The magnetic recording device according to configuration 2, wherein the second nonmagnetic layer is in contact with the first layer and the second magnetic layer.

(Configuration 4)
The magnetic recording device according to any one of configurations 1 to 3, wherein the first layer has a thickness of more than 0 nm and less than 3 nm.

(Configuration 5)
magnetic head,
electric circuit and
Equipped with
The magnetic head is
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a second non-magnetic layer provided between the first magnetic layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third nonmagnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer does not contain the third element, or the concentration of the third element in the first magnetic layer is lower than the concentration of the third element in the second magnetic layer,
The electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack.

(Configuration 6)
magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a second non-magnetic layer provided between the first magnetic layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer includes a first film and a second film, and the second film is located at a first position between the first nonmagnetic layer and the first film, and between the first film and the first film. in any of the second positions between the second nonmagnetic layer and the second nonmagnetic layer;
The first film includes the second element and the third element,
The second film does not contain the third element, or the concentration of the third element in the second film is lower than the concentration of the third element in the first film,
The electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack.

(Configuration 7)
7. The magnetic recording device according to configuration 6, wherein the composition of the first film is substantially the same as the composition of the second magnetic layer.

(Configuration 8)
8. The magnetic recording device according to any one of configurations 5 to 7, wherein the second nonmagnetic layer is in contact with the first magnetic layer and the second magnetic layer.

(Configuration 9)
9. The magnetic recording device according to any one of configurations 1 to 8, wherein the first nonmagnetic layer includes at least one selected from the group consisting of Ta, Ru, Cr, and Cu.

(Configuration 10)
10. The magnetic recording device according to any one of Structures 1 to 9, wherein the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, and Cr.

(Configuration 11)
11. The magnetic recording device according to any one of configurations 1 to 10, wherein the third nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, and Au.

(Configuration 12)
The magnetic recording device according to any one of Structures 1 to 11, wherein the first nonmagnetic layer has a thickness of 1 nm or more and 6 nm or less.

(Configuration 13)
The magnetic recording device according to any one of Structures 1 to 12, wherein the second nonmagnetic layer has a thickness of 1 nm or more and 4 nm or less.

(Configuration 14)
14. The magnetic recording device according to any one of configurations 1 to 13, wherein the third nonmagnetic layer has a thickness of 1 nm or more and 4 nm or less.

(Configuration 15)
15. The magnetic recording device according to any one of configurations 1 to 14, wherein the product of the saturation magnetization of the first magnetic layer and the thickness of the first magnetic layer is 1 nmT or more and 6 nmT or less.

(Configuration 16)
16. The magnetic recording device according to any one of configurations 1 to 15, wherein the product of the saturation magnetization of the second magnetic layer and the thickness of the second magnetic layer is 1 nmT or more and 9 nmT or less.

(Configuration 17)
17. The magnetic recording device according to any one of configurations 1 to 16, wherein the thickness of the second magnetic layer is 0.8 times or more and 3 times or less the thickness of the first magnetic layer.

(Configuration 18)
The laminate further includes a third magnetic layer provided between the third nonmagnetic layer and the second magnetic pole,
The third magnetic layer includes at least one fourth element selected from the group consisting of Co, Fe, and Ni, and the concentration of the fourth element in the third magnetic layer is 50 atomic % or more. 18. The magnetic recording device according to any one of 1 to 17.

(Configuration 19)
magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack.

(Configuration 20)
The rate of change in the electrical resistance of the laminate with respect to the change in the current density flowing through the laminate is positive when the current density is in a first range, negative when the current density is in a second range, and is positive when the current density is in the third range,
20. The magnetic recording device according to any one of configurations 1 to 19, wherein the current density of the first current is within the third range.

(Configuration 21)
When the first current is supplied to the stacked body, the first magnetization of the first magnetic layer has a component in the first direction,
When the first current is supplied to the stacked body, the second magnetization of the second magnetic layer has a component in the first direction,
When the second current in the first direction is supplied to the laminated body, the first magnetization has a component in the second direction from the first magnetic pole to the second magnetic pole, and the second current has a component in the second direction from the first magnetic pole to the second magnetic pole. smaller than the first current;
When the second current is supplied to the laminated body, the second magnetization has a component in the second direction,
21. The magnetic recording device according to configuration 20, wherein the current density of the second current is within the first range.

(Configuration 22)
further comprising a magnetic recording medium;
When the first current is supplied to the laminated body, the laminated body does not generate an alternating magnetic field, or the frequency of the alternating magnetic field generated from the laminated body is lower than the magnetic resonance frequency of the magnetic recording medium. 22. The magnetic recording device according to any one of configurations 1 to 21.

(Configuration 23)
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
Equipped with
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first layer includes Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Contains at least one selected from the group consisting of Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu,
A magnetic head, wherein a first current having a first direction from the second magnetic pole to the first magnetic pole is supplied to the stack.

(Configuration 24)
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
Equipped with
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer does not contain the third element, or the concentration of the third element in the first magnetic layer is lower than the concentration of the third element in the second magnetic layer,
A magnetic head, wherein a first current having a first direction from the second magnetic pole to the first magnetic pole is supplied to the stack.

(Configuration 25)
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
Equipped with
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer includes a first film and a second film, and the second film is located at a first position between the first nonmagnetic layer and the first film, and between the first film and the first film. in any of the second positions between the second nonmagnetic layer and the second nonmagnetic layer;
The first film includes the second element and the third element,
The second film does not contain the third element, or the concentration of the third element in the second film is lower than the concentration of the third element in the first film,
A magnetic head, wherein a first current having a first direction from the second magnetic pole to the first magnetic pole is supplied to the stack.

(Configuration 26)
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
Equipped with
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
A magnetic head, wherein a first current having a first direction from the second magnetic pole to the first magnetic pole is supplied to the stack.

According to the embodiments, a magnetic head and a magnetic recording device that can improve recording density can be provided. In the embodiment, the first magnetic pole 30 may be a trailing shield, and the second magnetic pole 31 may be a main magnetic pole.

In this specification, "perpendicular" and "parallel" are not only strictly perpendicular and strictly parallel, but also include variations in the manufacturing process, for example, and may be substantially perpendicular and substantially parallel. .

The 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, regarding the specific configuration of each element included in the magnetic head, such as the first magnetic pole, second magnetic pole, shield, laminated body, magnetic layer, nonmagnetic layer, layer, and wiring, those skilled in the art can appropriately determine the configuration from the known range. As long as the present invention can be carried out in the same manner and the same effects can be obtained by making a selection, the present invention falls within the scope of the present invention.

Combinations of any two or more elements of each specific example to the extent technically possible are also included within the scope of the present invention as long as they encompass the gist of the present invention.

In addition, all other magnetic heads and magnetic recording devices that can be implemented by those skilled in the art with appropriate design changes based on the magnetic head and magnetic recording device described above as embodiments of the present invention also encompass the gist of the present invention. within the scope of the present invention.

In addition, it is understood that various changes and modifications can be made by those skilled in the art within the scope of the idea of the present invention, and these changes and modifications also fall within the scope of the present invention. .

Although several embodiments of the invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included within the scope and gist of the invention, as well as within the scope of the invention described in the claims and its equivalents.

20...Laminated body, 20D...Electric circuit, 21-23...First to third magnetic layers, 21M, 22M...Magnetization, 21a, 21b...First, second film, 22Ma...Parameter, 22Mx...Component, 25...th 1 layer, 26... Second layer, 30... First magnetic pole, 30D... Recording circuit, 30F... Medium facing surface, 30M... Magnetization, 30c... Coil, 30i... Insulating section, 31... Second magnetic pole, 31M... Magnetization, 32 ...Shield, 41-43...First to third non-magnetic layer, 60...Recording section, 70...Reproducing section, 71...Magnetic reproducing element, 72a, 72b...First and second reproducing magnetic shield, 80...Magnetic recording medium , 81... Magnetic recording layer, 82... Medium substrate, 83... Magnetization, 85... Medium movement direction, θ1... Angle, 110 to 112, 119, 119a, 119b, 120... 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 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, 210... Magnetic recording device, AR... Arrow, D1, D2... First, second direction, G... Gain, Iw...recording current, J20...current density, JR1 to JR3...first to third range, Lg...distance, M1...parameter, R1...electrical resistance, ST1, ST2...first and second states, STT1 to STT3 ...spin transfer torque, T1, T2...first and second terminals, V1...applied voltage, W1, W2...wiring, i1, i2...first and second currents, je1, je2...first and second electron currents, t21, t22, t23, t25, t41, t42, t43...thickness, tm...time

Claims (9)

magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third nonmagnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first layer includes Ta, Zr, Hf, Mo, W, Tc, Re, Ru, Rh, Os, Ir, Pd, Pt, Mn, Cr, V, Ti, Sc, Y, La, Ce, Pr, Contains at least one selected from the group consisting of Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu,
the electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack ;
The rate of change in the electrical resistance of the laminate with respect to the change in the current density flowing through the laminate is positive when the current density is in a first range, negative when the current density is in a second range, and is positive when the current density is in the third range,
In the magnetic recording device , the current density of the first current is within the third range . magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a second non-magnetic layer provided between the first magnetic layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer does not contain the third element, or the concentration of the third element in the first magnetic layer is lower than the concentration of the third element in the second magnetic layer,
the electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack ;
The rate of change in the electrical resistance of the laminate with respect to the change in the current density flowing through the laminate is positive when the current density is in a first range, negative when the current density is in a second range, and is positive when the current density is in the third range,
In the magnetic recording device , the current density of the first current is within the third range . magnetic head,
electric circuit and
Equipped with
The magnetic head is
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a second non-magnetic layer provided between the first magnetic layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
The first magnetic layer includes a first film and a second film, and the second film is located at a first position between the first nonmagnetic layer and the first film, and between the first film and the first film. in any of the second positions between the second nonmagnetic layer and the second nonmagnetic layer;
The first film includes the second element and the third element,
The second film does not contain the third element, or the concentration of the third element in the second film is lower than the concentration of the third element in the first film,
the electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack ;
The rate of change in the electrical resistance of the laminate with respect to the change in the current density flowing through the laminate is positive when the current density is in a first range, negative when the current density is in a second range, and is positive when the current density is in the third range,
In the magnetic recording device , the current density of the first current is within the third range . 4. The magnetic recording device according to claim 3, wherein the composition of the first film is substantially the same as the composition of the second magnetic layer. 5. The magnetic recording device according to claim 1, wherein the first nonmagnetic layer includes at least one selected from the group consisting of Ta, Ru, Cr, and Cu. 6. The magnetic recording device according to claim 1, wherein the second nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, Au, and Cr. 7. The magnetic recording device according to claim 1, wherein the third nonmagnetic layer includes at least one selected from the group consisting of Cu, Ag, and Au. The laminate further includes a third magnetic layer provided between the third nonmagnetic layer and the second magnetic pole,
The third magnetic layer includes at least one fourth element selected from the group consisting of Co, Fe, and Ni, and the concentration of the fourth element in the third magnetic layer is 50 atomic % or more. 8. The magnetic recording device according to any one of items 1 to 7. magnetic head,
electric circuit and
Equipped with
The magnetic head includes:
a first magnetic pole;
a second magnetic pole;
a laminate provided between the first magnetic pole and the second magnetic pole;
including;
The laminate includes:
a first nonmagnetic layer;
a first magnetic layer provided between the first nonmagnetic layer and the second magnetic pole;
a first layer provided between the first magnetic layer and the second magnetic pole;
a second nonmagnetic layer provided between the first layer and the second magnetic pole;
a second magnetic layer provided between the second nonmagnetic layer and the second magnetic pole;
a third non-magnetic layer provided between the second magnetic layer and the second magnetic pole;
including;
The first magnetic layer includes at least one first element selected from the group consisting of Co, Fe, and Ni, and the concentration of the first element in the first magnetic layer is 50 atomic % or more,
The second magnetic layer includes at least one second element selected from the group consisting of Fe, Ni and Co, and at least one third element selected from the group consisting of Cr, V, Mn, Ti and Sc. , including;
the electrical circuit supplies a first current having a first direction from the second magnetic pole to the first magnetic pole to the stack ;
The rate of change in the electrical resistance of the laminate with respect to the change in the current density flowing through the laminate is positive when the current density is in a first range, negative when the current density is in a second range, and is positive when the current density is in the third range,
In the magnetic recording device , the current density of the first current is within the third range .

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