Magnetic sensor manufacturing method and magnetic sensor

Abstract

To magnetize a plurality of magnet layers in one step so as to have different magnetization states.SOLUTION: A magnetic sensor includes: a first magnetic field sensing element 2A having a magnetic field sensing axis 4A substantially parallel to a first direction X, two first magnet layers 21A and 22A arranged in a second direction Y substantially perpendicular to the first direction X, and a first soft magnetic layer 13A sandwiched between the two first magnet layers in the second direction; a second magnetic field sensing element 2B having a magnetic field sensing axis 4B substantially parallel to the second direction Y, two second magnet layers 21B and 22B arranged in the first direction X, and a second soft magnetic layer 13B sandwiched between the two second magnet layers in the first direction; and a substrate 3 supporting the first magnetic field sensing element 2A and the second magnetic field sensing element 2B. An external magnetic field is applied from a direction W substantially equiangular to the first direction X and the second direction Y, and the two first magnet layers 21A and 22A and the two second magnet layers 21B and 22B are magnetized.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a magnetic sensor and a magnetic sensor. [Background technology]

[0002] Magnetic sensors capable of detecting multiple magnetic field detection directions are known. Patent Document 1 describes a magnetic sensor in which two types of sensor bridges are supported on a substrate. The two types of sensor bridges detect two orthogonal magnetic field components, respectively. The substrate is equipped with multiple magnets that apply a bias magnetic field to each sensor bridge, and the multiple magnets are magnetized in the same direction. Each sensor bridge is composed of four elements, and the long axes of two elements are orthogonal to the long axes of the other two elements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2014-515470 Summary of the Invention [Problem to be solved by the invention]

[0004] In the magnetic sensor described in Patent Document 1, multiple magnets can be magnetized in a single process. Meanwhile, a bias magnetic field is applied to stabilize the magnetization state of the elements of the magnetic sensor and improve the linearity and symmetry of the output. Because the bias magnetic field is parallel to the long axis of one set of elements but parallel to the short axis of the other set of elements, it is difficult to stabilize the magnetization state of the other set of elements. It is desirable to magnetize the magnets so that they have different magnetization states according to the orientation of the elements.

[0005] An object of the present disclosure is to provide a method for manufacturing a magnetic sensor that can magnetize multiple magnet layers to have different magnetization states in a single process. [Means for solving the problem]

[0006] The present disclosure relates to a magnetic field sensor having a magnetic field sensing axis substantially parallel to a first direction, two first magnet layers arranged in a second direction substantially perpendicular to the first direction, and a magnetic field sensor sandwiched between the two first magnet layers in the second direction. , the magnetization direction rotates due to an external magnetic field 1st magnetization free layer a first magnetic field sensing element having a magnetic field sensing axis substantially parallel to the second direction, two second magnet layers arranged in the first direction, and a magnetic field sensing element sandwiched between the two second magnet layers in the first direction; , the magnetization direction rotates due to an external magnetic field Second magnetization free layer and a substrate supporting the first magnetic field sensing element and the second magnetic field sensing element. The two first magnet layers apply a bias magnetic field in a second direction to the first magnetization free layer, and the two second magnet layers apply a bias magnetic field in a first direction to the second magnetization free layer. The present invention relates to a method for manufacturing a magnetic sensor, which includes two first magnet layers, two second magnet layers, and a first magnetization free layer and the second magnetization free layer With the two first magnet layers and the two second magnet layers supported on the substrate, an external magnetic field is applied from directions at approximately equal angles to the first direction and the second direction to magnetize the two first magnet layers and the two second magnet layers. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a method for manufacturing a magnetic sensor that can magnetize a plurality of magnet layers to have different magnetization states in a single process. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram of a magnetic sensor according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a plan view of the magnetization free layer and the magnet layer shown in FIG. [Figure 3] FIG. 2 is a conceptual diagram showing a method for magnetizing a magnet layer. [Figure 4] FIG. 4 is a schematic configuration diagram of a magnetic sensor according to a modified example of the first embodiment. [Figure 5] FIG. 10 is a conceptual diagram showing a method for magnetizing a magnet layer of a magnetic sensor according to a second embodiment of the present disclosure. [Figure 6] FIG. 10 is a conceptual diagram showing a method for magnetizing a magnet layer of a magnetic sensor according to a third embodiment of the present disclosure. [Figure 7] FIG. 10 is a conceptual diagram showing a method for magnetizing a magnet layer of a magnetic sensor according to a fourth embodiment of the present disclosure. [Figure 8] FIG. 10 is a conceptual diagram showing a method for magnetizing a magnet layer of a magnetic sensor according to a fifth embodiment of the present disclosure. [Figure 9] FIG. 13 is a conceptual diagram showing a method for magnetizing a magnet layer of a magnetic sensor according to a sixth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] An embodiment of the magnetic sensor of the present disclosure will be described with reference to the drawings. In the following description and drawings, the first direction X is approximately parallel to the magnetic detection direction of the first magnetic field detection element 2A, and the second direction Y is approximately parallel to the magnetic detection direction of the second magnetic field detection element 2B. The third direction Z coincides with the stacking direction of the laminate described below. The first direction X and the second direction Y are parallel to the element mounting surface 3A of the substrate 3. The first direction X, the second direction Y, and the third direction Z are approximately perpendicular to each other.

[0010] (First embodiment) FIG. 1 is a cross-sectional view showing a schematic configuration of a magnetic sensor 1 according to a first embodiment, and FIG. 2 is a plan view of a magnetization free layer and a magnet layer taken along line AA in FIG. 1. Referring to FIG. 1, the magnetic sensor 1 includes a first magnetic field detection element 2A, a second magnetic field detection element 2B, and a substrate 3 supporting the first magnetic field detection element 2A and the second magnetic field detection element 2B. The first magnetic field detection element 2A has a magnetic field detection axis (magnetic field detection direction) 4A parallel to a first direction X, and the second magnetic field detection element 2B has a magnetic field detection axis (magnetic field detection direction) 4B parallel to a second direction Y. The first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the second (or first) magnetic field detection element 2B (2A) corresponds to the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane. An insulating layer 5 made of Al2O3 is provided between the first magnetic field sensing element 2A and the second magnetic field sensing element 2B.

[0011] The first magnetic field sensing element 2A and the second magnetic field sensing element 2B each have a bottom electrode layer 6, a stack 7, and an top electrode layer 14. The stack 7 has an antiferromagnetic layer 8, an outer magnetization pinned layer 9, a non-magnetic intermediate layer 10, an inner magnetization pinned layer 11, a spacer layer 12, and a magnetization free layer 13, which are stacked in the above order from the bottom electrode layer 6 to the top electrode layer 14 in the third direction Z. The inner magnetization pinned layer 11 is sometimes referred to as the magnetization pinned layer 11. A sense current flows in the stack 7 in the third direction Z due to the bottom electrode layer 6 and the top electrode layer 14. In the following description, the laminate 7, inner magnetization pinned layer 11, spacer layer 12, and magnetization free layer 13 of the first magnetic field detection element 2A may be referred to as the first laminate 7A, first magnetization pinned layer 11A, first spacer layer 12A, and first magnetization free layer 13A, respectively, and the laminate 7, inner magnetization pinned layer 11, spacer layer 12, and magnetization free layer 13 of the second magnetic field detection element 2B may be referred to as the second laminate 7B, second magnetization pinned layer 11B, second spacer layer 12B, and second magnetization free layer 13B, respectively. Also, the first magnetization free layer 13A may be referred to as the first soft magnetic layer 13A, and the second magnetization free layer 13B may be referred to as the second soft magnetic layer 13B.

[0012] The free magnetization layer 13 is a soft magnetic layer whose magnetization direction rotates in response to an external magnetic field and may be formed of, for example, NiFe. The spacer layer 12 is a nonmagnetic layer located between the free magnetization layer 13 and the fixed magnetization layer 11. The spacer layer 12 may be formed of a nonmagnetic insulator such as Al2O3 or MgO, or a nonmagnetic conductor such as Cu. When the spacer layer 12 is a nonmagnetic insulator, the first and second magnetic field sensing elements 2A and 2B function as tunneling magnetoresistance (TMR) elements. When the spacer layer 12 is a nonmagnetic conductor, the first and second magnetic field sensing elements 2A and 2B function as giant magnetoresistance (GMR) elements. The TMR element has a larger MR change rate than the GMR element, allowing the output voltage of the magnetic sensor 1 to be increased.

[0013] The inner magnetization pinned layer 11 is a ferromagnetic layer sandwiched between the outer magnetization pinned layer 9 and the spacer layer 12. The inner magnetization pinned layer 11 is antiferromagnetically coupled to the outer magnetization pinned layer 9 via a nonmagnetic intermediate layer 10 made of Ru, Rh, or the like. The outer magnetization pinned layer 9 is a ferromagnetic layer exchange-coupled to the antiferromagnetic layer 8. The antiferromagnetic layer 8 can be made of PtMn, IrMn, NiMn, or the like. The magnetization directions of the inner magnetization pinned layer 11 and the outer magnetization pinned layer 9 are fixed, and are antiparallel to each other. The magnetization direction of the first magnetization pinned layer 11A is fixed in a first direction X, and the magnetization direction of the second magnetization pinned layer 11B is fixed in a second direction Y. The magnetization direction (first direction X) of the first magnetization fixed layer 11A coincides with the magnetic field sensing axis 4A of the first magnetic field sensing element 2A, and the magnetization direction (second direction Y) of the second magnetization fixed layer 11B coincides with the magnetic field sensing axis 4B of the second magnetic field sensing element 2B.

[0014] As shown in FIG. 2, the first magnetic field sensing element 2A has two first magnet layers 21A and 22A arranged in a second direction Y. The two first magnet layers 21A and 22A sandwich the first magnetization free layer 13A in the second direction Y. The two first magnet layers 21A and 22A apply a bias magnetic field in the second direction Y to the first magnetization free layer 13A. The second magnetic field sensing element 2B has two second magnet layers 21B and 22B arranged in a first direction X. The two second magnet layers 21B and 22B sandwich the second magnetization free layer 13B in the first direction X. The two second magnet layers 21B and 22B apply a bias magnetic field in the first direction X to the second magnetization free layer 13B. The first magnet layers 21A and 22A and the second magnet layers 21B and 22B have the same configuration and shape.

[0015] The first and second magnet layers 21A, 22A, 21B, and 22B are made of a hard magnetic material such as CoPt or CoCrPt. As shown in FIG. 1, the second magnet layers 21B and 22B are provided over almost the entire area of ​​the second laminate 7B in the third direction Z. The second magnet layers 21B and 22B only need to be provided on the sides of the second magnetization free layer 13B in the first direction X. Although not shown, the first magnet layers 21A and 22A are provided over almost the entire area of ​​the first laminate 7A in the third direction Z. The first magnet layers 21A and 22A only need to be provided on the sides of the first magnetization free layer 13A in the second direction Y. Insulating layers 23 made of Al2O3 or the like are provided between the first magnet layers 21A and 22A and the first laminate 7A and between the second magnet layers 21B and 22B and the second laminate 7B. The insulating layer 23 prevents the sense current flowing through the stack 7 from leaking to the magnet layers 21A, 22A, 21B, and 22B, and in particular prevents short-circuiting between the magnetization free layer 13 and the magnetization fixed layer 11. Note that the insulating layer 23 is not shown in FIG.

[0016] As shown in FIG. 2, the first magnetization free layer 13A is formed so that the second direction Y is longer and narrower overall than the first direction X. Therefore, the shape anisotropy effect makes it easier for the magnetization direction of the first magnetization free layer 13A to orient in the second direction Y. Also, as described above, a bias magnetic field is applied to the first magnetization free layer 13A in the second direction Y by the first magnet layers 21A and 22A. For the above reasons, the first magnetization free layer 13A is generally magnetized in the second direction Y when no external magnetic field is applied (hereinafter referred to as zero magnetic field). Similarly, the second magnetization free layer 13B is formed so that the first direction X is longer and narrower overall than the second direction Y. Therefore, the shape anisotropy effect makes it easier for the magnetization direction of the second magnetization free layer 13B to orient in the first direction X. As described above, a bias magnetic field is applied to the second magnetization free layer 13B in the first direction X by the second magnet layers 21B and 22B. For the reasons described above, the second magnetization free layer 13B is generally magnetized in the first direction X in zero magnetic field. However, the shapes of the first magnetization free layer 13A and the second magnetization free layer 13B are not limited to these. For example, the first magnetization free layer 13A may be square when viewed from the third direction Z, or may be formed so that the first direction X is longer and thinner than the second direction Y. The same applies to the second magnetization free layer 13B.

[0017] The first magnetization pinned layer 11A is magnetized generally in a first direction X. When an external magnetic field is applied in the first direction X, the magnetization direction of the first magnetization free layer 13A rotates clockwise or counterclockwise in FIG. 2 depending on the strength of the external magnetic field. This changes the relative angle between the magnetization direction of the first magnetization pinned layer 11A and the magnetization direction of the first magnetization free layer 13A, and the electrical resistance of the first magnetic field sensing element 2A to the sense current changes. Based on this change in electrical resistance, the first magnetic field sensing element 2A detects the strength of the external magnetic field in the magnetic field detection direction (first direction X). The second magnetic field sensing element 2B also detects the strength of the external magnetic field in the magnetic field detection direction (second direction Y) using a similar principle.

[0018] Next, a method for manufacturing the magnetic sensor 1 described above will be described. First, a lower electrode layer 6, a laminate 7, and an upper electrode layer 14 are formed on a substrate 3 for each of the first magnetic field detection element 2A and the second magnetic field detection element 2B. The first magnetization fixed layer 11A of the first laminate 7A and the second magnetization fixed layer 11B of the second laminate 7B can be magnetized by, for example, a method combining magnetic field application and local heating. Specifically, a laser beam is irradiated onto the first magnetic field detection element 2A (first magnetization fixed layer 11A) while an external magnetic field is applied from a first direction X, thereby heating the first magnetic field detection element 2A (first magnetization fixed layer 11A). Next, a laser beam is irradiated onto the second magnetic field detection element 2B (second magnetization fixed layer 11B) while an external magnetic field is applied from a second direction Y, thereby heating the second magnetic field detection element 2B (second magnetization fixed layer 11B). By this method, the first magnetization fixed layer 11A and the second magnetization fixed layer 11B supported by the same substrate 3 can be magnetized in different directions.

[0019] Next, the first magnet layers 21A, 22A and the second magnet layers 21B, 22B are formed. Subsequently, the first magnet layers 21A, 22A and the second magnet layers 21B, 22B are magnetized. As shown in FIG. 3, an external magnetic field is applied from a direction W that is approximately equiangular with the first direction X and the second direction Y to magnetize the two first magnet layers 21A, 22A and the two second magnet layers 21B, 22B. This process is performed while the two first magnet layers 21A, 22A and the two second magnet layers 21B, 22B are supported on the substrate 3, so the two first magnet layers 21A, 22A and the two second magnet layers 21B, 22B can be magnetized simultaneously. Then, the upper electrode layers 14 of the first magnetic field detection element 2A and the second magnetic field detection element 2B are formed. It is preferable that the direction W is inclined at 45 degrees from both the first direction X and the second direction Y, but it may vary within a small range (for example, about 43 to 47 degrees).

[0020] In FIG. 3, the magnetic flux generated by a magnetic field application device (not shown) such as an electromagnet flows from the lower left to the upper right (in the direction W). flowThe first magnet layer 21A on the lower side in the figure is located upstream in the direction of application of the external magnetic field, and the first magnet layer 22A on the upper side in the figure is located downstream in the direction of application of the external magnetic field. Therefore, the first magnet layer 21A on the lower side in the figure is referred to as the first upstream magnet layer 21A, and the first magnet layer 22A on the upper side in the figure is referred to as the first downstream magnet layer 22A. Furthermore, a portion of the magnetic flux B that enters the first magnet layer 21A on the lower side in the figure passes through the first magnetization free layer 13A and the upper first magnet layer 22A and exits from the upper first magnet layer 22A. Therefore, the lower end of the first magnetization free layer 13A is referred to as the first upstream end 15A in the direction of application of the external magnetic field, and the upper end is referred to as the first downstream end 16A in the direction of application of the external magnetic field. The first upstream magnet layer 21A faces the first upstream end 15A of the first magnetization free layer 13A, and the first downstream magnet layer 22A faces the first downstream end 16A of the first magnetization free layer 13A. The same applies to the second magnet layers 21B and 22B. The second upstream magnet layer 21B faces the second upstream end 15B of the second magnetization free layer 13B, and the second downstream magnet layer 22B faces the second downstream end 16B of the second magnetization free layer 13B.

[0021] 3, the magnetic flux B passing through the first upstream magnet layer 21A, the first magnetization free layer 13A, and the first downstream magnet layer 22A bends inside the first upstream magnet layer 21A and tilts in the second direction Y, then travels substantially in the second direction Y in the first magnetization free layer 13A, bends again in the first downstream magnet layer 22A, and faces the application direction W of the external magnetic field. In other words, because the first magnetization free layer 13A has a magnetic flux collecting function or a function as a yoke, the path of the magnetic flux B is bent along the first magnetization free layer 13A.

[0022] By utilizing this phenomenon, the first magnet layers 21A and 22A can be magnetized at an angle closer to the second direction Y than the application direction W of the external magnetic field. When the first upstream magnet layer 21A is divided in the second direction Y into a half 17 close to the first magnetization free layer 13A and another half 18 away from the first magnetization free layer 13A, the average magnetization direction of the half 17 is inclined in the second direction Y more than the average magnetization direction of the other half 18. Note that the average magnetization direction means the average of the magnetization directions of the individual grains of the first magnet layer 21A. Similarly, when the first downstream magnet layer 22A is divided in the second direction Y into a half 19 close to the first magnetization free layer 13A and another half 20 away from the first magnetization free layer 13A, the average magnetization direction of the half 19 is inclined in the second direction Y more than the average magnetization direction of the other half 20. As a result, the angle formed between the average magnetization direction of each of the two first magnet layers 21A, 22A and the second direction Y is between more than 0 degrees and less than 45 degrees. The magnetization directions of the half 17 of the first upstream magnet layer 21A and the half 19 of the first downstream magnet layer 22A contribute relatively greatly to the direction of the bias magnetic field applied to the first magnetization free layer 13A. Therefore, according to this embodiment, a bias magnetic field that is substantially oriented in the second direction Y can be applied to the first magnetization free layer 13A. The same applies to the second magnetization free layer 13B.

[0023] 2, the center line 24A of the first magnetization free layer 13A, which is parallel to the second direction Y, coincides with the center lines 25A and 26A of the two first magnet layers 21A and 22A, which are also parallel to the second direction Y. This allows the bias magnetic field applied to the first magnetization free layer 13A to be directed more in the second direction Y. It is preferable that the dimension D1A of the first magnet layers 21A and 22A in the first direction X be larger than the dimension D2A of the first magnetization free layer 13A in the first direction X. This allows the bias magnetic field directed in the second direction Y to be applied across the entire width of the first magnetization free layer 13A in the first direction X.

[0024] The same applies to the second magnet layers 21B and 22B. In each of the two second magnet layers 21B and 22B, the magnetization direction of the half 17 or 19 closest to the second magnetization free layer 13B is inclined toward the first direction X more than the magnetization direction of the other half 18 or 20 farther from the second magnetization free layer 13B. The angle between the average magnetization direction of each of the two second magnet layers 21B and 22B and the first direction X is greater than 0 degrees and less than 45 degrees. As shown in FIG. 2 , the center line 24B of the second magnetization free layer 13B, which is parallel to the first direction X, coincides with the center lines 25B and 26B of the two second magnet layers 21B and 22B, which are also parallel to the first direction X. Preferably, the dimension D1B of the second magnet layers 21B and 22B in the second direction Y is greater than the dimension D2B of the second magnetization free layer 13B in the second direction Y.

[0025] FIG. 4 is a cross-sectional view showing a schematic configuration of a magnetic sensor 1 according to another modification of the first embodiment. The configuration and effects, which are not described here, are the same as those of the first embodiment. As shown in FIG. 4, the two second magnet layers 21B and 22B each have a ferromagnetic layer 27 and an antiferromagnetic layer 28, and the ferromagnetic layer 27 faces the second magnetization free layer 13B in the first direction X. Although not shown, the two first magnet layers 21A and 22A each have a ferromagnetic layer 27 and an antiferromagnetic layer 28, and the ferromagnetic layer 27 faces the first magnetization free layer 13A in the second direction Y. The ferromagnetic layer 27 is made of CoFe. The antiferromagnetic layer 28 is made of an alloy such as IrMn, Fe—Mn, Ni—Mn, Pt—Mn, or Pd—Pt—Mn, and is strongly exchange-coupled with the adjacent ferromagnetic layer 27. The ferromagnetic layer 27 applies a bias magnetic field to the magnetization free layer 13, similar to the first and second magnet layers 21A, 22A, 21B, and 22B in the first embodiment. The magnetization direction of the ferromagnetic layer 27 is firmly fixed by the antiferromagnetic layer 28, so that hysteresis in the first and second magnet layers 21A, 22A, 21B, and 22B at zero magnetic field is suppressed. Exchange coupling between the antiferromagnetic layer 28 and the ferromagnetic layer 27 is achieved by locally heating the ferromagnetic layer 27 and the antiferromagnetic layer 28 while an external magnetic field is applied.

[0026] (Second embodiment) FIG. 5 is a diagram similar to FIG. 2 of the magnetic sensor 1 according to the second embodiment, showing a plan view of the magnetization free layer and the magnet layer. The configurations and effects omitted from the description are the same as those of the first embodiment. In this embodiment, the first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane corresponds to the second (or first) magnetic field detection element 2B (2A). Therefore, the following description will mainly focus on the first magnetic field detection element 2A.

[0027] In this embodiment, the center line 24A of the first magnetization free layer 13A, which is parallel to the second direction Y, and the center lines 25A and 26A of the two first magnet layers 21A and 22A, which are also parallel to the second direction Y, are offset from each other in the first direction X. Specifically, the center line 24A of the first magnetization free layer 13A is located between the center line 25A of the first upstream magnet layer 21A and the center line 26A of the first downstream magnet layer 22A, and the center line 25A of the first upstream magnet layer 21A is located closer to the viewer in the application direction W of the external magnetic field than the center line 26A of the first downstream magnet layer 22A. Because magnetic flux B is applied from the lower left to the upper right in FIG. 5, the lower left of the first upstream magnet layer 21A and the first downstream magnet layer 22A are magnetized to a south pole and the upper right is magnetized to a north pole. Therefore, the north pole of the first upstream magnet layer 21A and the south pole of the first downstream magnet layer 22A face each other in the second direction Y, and a magnetic field B' facing the second direction Y is formed around the first magnetization free layer 13A. This causes the first magnetization free layer 13A to be magnetized in a direction closer to the second direction Y. Note that only one of the center lines 25A and 26A may be deviated from the center line 24A in the first direction X.

[0028] Similarly, the center line 24B of the second magnetization free layer 13B, which is parallel to the first direction X, and the center lines 25B and 26B of the two second magnet layers 21B and 22B, which are also parallel to the first direction X, are offset from each other in the second direction Y. Specifically, the center line 24B of the second magnetization free layer 13B is located between the center line 25B of the second upstream magnet layer 21B and the center line 26B of the second downstream magnet layer 22B, and the center line 25B of the second upstream magnet layer 21B is located closer to the front than the center line 26B of the second downstream magnet layer 22B in the application direction W of the external magnetic field. Note that only one of the center lines 25B and 26B may be offset from the center line 24B in the second direction Y.

[0029] (Third embodiment) FIG. 6 is a diagram similar to FIG. 2 of the magnetic sensor 1 according to the third embodiment, showing a plan view of the magnetization free layer and the magnet layer. The configurations and effects omitted from the description are the same as those of the first embodiment. In this embodiment, the first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane corresponds to the second (or first) magnetic field detection element 2B (2A). Therefore, the following description will mainly focus on the first magnetic field detection element 2A.

[0030] The first magnetization free layer 13A has a triangular first upstream end region 31A facing the first upstream magnet layer 21A and a triangular first downstream end region 32A facing the first downstream magnet layer 22A. The first upstream magnet layer 21A has a first upstream recess 33A that accommodates the first upstream end region 31A, and the first downstream magnet layer 22A has a first downstream recess 34A that accommodates the first downstream end region 32A. Similarly, the second magnetization free layer 13B has a triangular second upstream end region 31B facing the second upstream magnet layer 21B and a triangular second downstream end region 32B facing the second downstream magnet layer 22B. The second upstream magnet layer 21B has a second upstream recess 33B that accommodates the second upstream end region 31B, and the second downstream magnet layer 22B has a second downstream recess 34B that accommodates the second downstream end region 32B.

[0031] When the first magnetization free layer 13A is rectangular as viewed from the third direction Z, a demagnetizing field is generated at the end of the first magnetization free layer 13A facing the first magnet layers 21A and 22A. Due to the influence of the demagnetizing field, even when the external magnetic field disappears, diagonal magnetization remains at the end of the first magnetization free layer 13A facing the first magnet layers 21A and 22A, which may cause hysteresis in the output of the magnetic sensor 1. In contrast, in this embodiment, the end regions 31A and 32A of the first magnetization free layer 13A facing the first magnet layers 21A and 22A are triangular, thereby reducing the influence of the demagnetizing field and suppressing hysteresis. The same applies to the second magnetic field detection element 2B.

[0032] (Fourth embodiment) FIG. 7 is a diagram similar to FIG. 6 of the magnetic sensor 1 according to the fourth embodiment, showing a plan view of the magnetization free layer and the magnet layer. The configurations and effects omitted are the same as those of the third embodiment. In this embodiment, the first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane corresponds to the second (or first) magnetic field detection element 2B (2A). In this embodiment, the dimension L1 in the second direction Y of the first upstream magnet layer 21A of the first magnetic field detection element 2A is larger than the dimension W1 in the first direction X, and the dimension L2 in the second direction Y of the first downstream magnet layer 22A is larger than the dimension W2 in the first direction X. This allows the direction in which the shape anisotropy effect of the first upstream magnet layer 21A and the first downstream magnet layer 22A occurs to be aligned with the second direction Y, and the first magnetization free layer 13A is magnetized in a direction closer to the second direction Y. Similarly, the dimension L3 in the first direction X of the first upstream magnet layer 21B of the second magnetic field detection element 2B is larger than the dimension W3 in the second direction Y, and the dimension L4 in the first direction X of the second downstream magnet layer 22B is larger than the dimension W4 in the second direction Y. This allows the direction in which the shape anisotropy effect of the second upstream magnet layer 21B and the second downstream magnet layer 22B occurs to be aligned with the first direction X, and the second magnetization free layer 13B is magnetized in a direction closer to the first direction X. Although not shown in the drawings, this embodiment can be combined with the first to third embodiments and the fourth and fifth embodiments.

[0033] (Fifth embodiment) FIG. 8 shows the configuration of a magnetic sensor 1 according to a fifth embodiment. The configuration and effects, which are not described here, are the same as those of the first embodiment. FIG. 8(a) is a side view of the magnetic sensor 1 as seen from the second direction Y. FIG. 8(b) is a view similar to FIG. 2, showing a plan view of the magnetization free layer and the magnet layer as seen from the line AA in FIG. 8(a). In this embodiment, the first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane corresponds to the second (or first) magnetic field detection element 2B (2A). Therefore, the following description will mainly focus on the first magnetic field detection element 2A.

[0034] In this embodiment, at least one (two in this embodiment) first shield layer 41A, 42A is provided to shield the first magnetic field detection element 2A, and at least one (two in this embodiment) second shield layer 41B, 42B is provided to shield the second magnetic field detection element 2B. The first shield layers 41A, 42A are elongated in the second direction Y, and the second shield layers 41B, 42B are elongated in the first direction X. The two first shield layers 41A, 42A sandwich the first magnetic field detection element 2A in the third direction Z, and the two second shield layers 41B, 42B sandwich the second magnetic field detection element 2B in the third direction Z. The first shield layers 41A, 42A and the second shield layers 41B, 42B are formed of a soft magnetic material such as NiFe.

[0035] Generally, a soft magnetic material having an elongated shape has a property that magnetization is easily saturated in the longitudinal direction but is difficult to saturate in the lateral direction. Therefore, the first shield layers 41A and 42A shield an external magnetic field in the first direction X, but the magnetization is easily saturated in the second direction Y, and they no longer function as a shield. However, if the external magnetic field is too strong, the shielding effect in the first direction X also decreases, so it is preferable that the external magnetic field is strong enough to prevent magnetic saturation of the first shield layers 41A and 42A at least in the first direction X. As a result, the component of the external magnetic field in the second direction Y predominates around the first shield layers 41A and 42A, as shown in FIG. 8 As shown in (b), the external magnetic field applied to the first magnetic field sensing element 2A tends to be oriented in the second direction Y. The same is true for the second magnetic field sensing element 2B. 8 Although (b) shows the first and second magnetic field sensing elements 2A and 2B of the first embodiment, this embodiment can also be combined with the second or third embodiment.

[0036] (Sixth embodiment) FIG. 9 shows the configuration of the magnetic sensor 1 according to the sixth embodiment. The configuration and effects, the description of which is omitted, are the same as those of the fifth embodiment. FIG. 9(a) is a view similar to FIG. 2 and is a plan view of the magnetic sensor 1 as seen from the third direction Z. FIG. 9(b) shows a side view of the magnetization free layer and the magnet layer as seen from the line AA in FIG. 9(a). In this embodiment, the first magnetic field detection element 2A and the second magnetic field detection element 2B have the same configuration, and the first (or second) magnetic field detection element 2A (2B) rotated 90 degrees on the XY plane corresponds to the second (or first) magnetic field detection element 2B (2A).

[0037] The configurations of the first shield layers 41A, 42A and the second shield layers 41B, 42B are the same as those of the fifth embodiment, except that the two first shield layers 41A, 42A sandwich the first magnetic field detection element 2A in the second direction Y, and the two second shield layers 41B, 42B sandwich the second magnetic field detection element 2B in the first direction X. This configuration also achieves the same effect because the component of the external magnetic field in the second direction Y predominates around the first shield layers 41A, 42A. Furthermore, in the fifth and sixth embodiments, one first shield layer 41A or 42A may be disposed near the first magnetic field detection element 2A, and one second shield layer 41B or 42B may be disposed near the second magnetic field detection element 2B. That is, one first shield layer 41A or 42A and one second shield layer 41B or 42B may be omitted from the fifth and sixth embodiments.

[0038] (Additional Note) This specification includes the following disclosure. [Manufacturing method 1] a first magnetic field sensing element having a magnetic field sensing axis substantially parallel to a first direction, two first magnet layers arranged in a second direction substantially perpendicular to the first direction, and a first soft magnetic layer sandwiched between the two first magnet layers in the second direction; a second magnetic field sensing element having a magnetic field sensing axis substantially parallel to the second direction, two second magnet layers arranged in the first direction, and a second soft magnetic layer sandwiched between the two second magnet layers in the first direction; a substrate supporting the first magnetic field sensing element and the second magnetic field sensing element; A method for manufacturing a magnetic sensor having A method for manufacturing a magnetic sensor, comprising: applying an external magnetic field from a direction at an approximately equal angle to the first direction and the second direction while the two first magnet layers, the two second magnet layers, the first soft magnetic layer, and the second soft magnetic layer are supported on the substrate, thereby magnetizing the two first magnet layers and the two second magnet layers. [Manufacturing method 2] the first magnetic field detection element includes a first magnetization free layer whose magnetization direction rotates in response to an external magnetic field, a first magnetization fixed layer whose magnetization direction is fixed in the first direction, and a non-magnetic first spacer layer located between the first magnetization free layer and the first magnetization fixed layer; the second magnetic field detection element has a second magnetization free layer whose magnetization direction rotates due to an external magnetic field, a second magnetization fixed layer whose magnetization direction is fixed in the second direction, and a non-magnetic second spacer layer located between the second magnetization free layer and the second magnetization fixed layer; The method for manufacturing a magnetic sensor according to manufacturing method 1, wherein the first magnetization free layer is the first soft magnetic layer, and the second magnetization free layer is the second soft magnetic layer. [Manufacturing method 3] A method for manufacturing a magnetic sensor described in manufacturing method 2, wherein the center line of the first magnetization free layer parallel to the second direction coincides with the center lines of the two first magnet layers parallel to the second direction, and the center line of the second magnetization free layer parallel to the first direction coincides with the center lines of the two second magnet layers parallel to the first direction. [Manufacturing method 4] the first magnetization free layer has a first upstream end and a first downstream end in the direction of application of the external magnetic field, the two first magnet layers include a first upstream magnet layer facing the first upstream end and a first downstream magnet layer facing the first downstream end, a center line of the first magnetization free layer parallel to the second direction is located between center lines of the two first magnet layers parallel to the second direction, a center line of the first upstream magnet layer parallel to the second direction is located on the near side in the application direction of the external magnetic field relative to a center line of the first downstream magnet layer parallel to the second direction, the second magnetization free layer has a second upstream end and a second downstream end in the direction of application of the external magnetic field, the two second magnet layers include a second upstream magnet layer facing the second upstream end and a second downstream magnet layer facing the second downstream end, a center line of the second magnetization free layer parallel to the first direction is located between center lines of the two second magnet layers parallel to the first direction, A method for manufacturing a magnetic sensor described in manufacturing method 2, wherein the center line of the second upstream magnet layer parallel to the first direction is located closer to the application direction of the external magnetic field than the center line of the second downstream magnet layer parallel to the first direction. [Manufacturing method 5] a dimension of the first magnet layer in the first direction being larger than a dimension of the first magnetization free layer in the first direction; 5. A method for manufacturing a magnetic sensor according to any one of manufacturing methods 2 to 4, wherein the dimension of the second magnet layer in the second direction is larger than the dimension of the second magnetization free layer in the second direction. [Manufacturing method 6] the first magnetization free layer has two triangular first end regions facing the two first magnet layers, A method for manufacturing a magnetic sensor described in any one of manufacturing methods 2 to 5, wherein the second magnetization free layer has two triangular second end regions facing the two second magnet layers. [Manufacturing method 7] the two first magnet layers have first recesses that accommodate the first end regions; The method for manufacturing a magnetic sensor according to manufacturing method 6, wherein the two second magnet layers have second recesses that accommodate the second end regions. [Manufacturing method 8] After forming the first magnetization fixed layer, the first magnetization fixed layer is heated while applying a magnetic field in the first direction to magnetize the first magnetization fixed layer; A method for manufacturing a magnetic sensor described in any one of manufacturing methods 2 to 7, wherein after forming the second magnetization fixed layer, the second magnetization fixed layer is heated while applying a magnetic field in the second direction to magnetize the second magnetization fixed layer. [Manufacturing method 9] the dimensions of the two first magnet layers in the second direction are greater than the dimensions in the first direction; The dimensions of the two second magnet layers in the first direction are larger than the dimensions in the second direction; 9. A method for manufacturing the magnetic sensor according to any one of manufacturing methods 1 to 8. [Manufacturing method 10] at least one first shield layer elongated in the second direction and shielding the first magnetic field sensing element; at least one second shield layer elongated in the first direction and shielding the second magnetic field sensing element; 10. A method for manufacturing the magnetic sensor according to any one of manufacturing methods 1 to 9, comprising: [Manufacturing method 11] the at least one first shield layer includes two first shield layers sandwiching the first magnetic field sensing element in a third direction orthogonal to the first direction and the second direction; A method for manufacturing a magnetic sensor according to manufacturing method 10, wherein the at least one second shield layer has two second shield layers sandwiching the second magnetic field sensing element in the third direction. [Manufacturing method 12] the at least one first shield layer includes two first shield layers sandwiching the first magnetic field sensing element in the second direction; 12. The method for manufacturing a magnetic sensor according to manufacturing method 10 or 11, wherein the at least one second shield layer has two second shield layers sandwiching the second magnetic field sensing element in the first direction. [Manufacturing method 13] The two first magnet layers and the two second magnet layers are each made of a hard magnetic material. 13. A method for manufacturing a magnetic sensor according to any one of methods 1 to 12. [Manufacturing method 14] A method for manufacturing a magnetic sensor described in any one of manufacturing methods 1 to 13, wherein each of the two first magnet layers and the two second magnet layers has a ferromagnetic layer and an antiferromagnetic layer, and each of the two first magnet layers and the two second magnet layers is locally heated while the external magnetic field is applied, thereby magnetizing each of the ferromagnetic layers. [Configuration 1] a first magnetic field sensing element having a magnetic field sensing axis substantially parallel to a first direction, a second magnetic field sensing element having a magnetic field sensing axis parallel to a second direction substantially perpendicular to the first direction, and a substrate supporting the first magnetic field sensing element and the second magnetic field sensing element; the first magnetic field detection element includes a first magnetization free layer whose magnetization direction rotates due to an external magnetic field, a first magnetization fixed layer whose magnetization direction is fixed in the first direction, a first non-magnetic spacer layer located between the first magnetization free layer and the first magnetization fixed layer, and two first magnet layers arranged in the second direction and sandwiching the first magnetization free layer in the second direction; The second magnetic field detection element has a second magnetization free layer whose magnetization direction rotates due to an external magnetic field, a second magnetization fixed layer whose magnetization direction is fixed in the second direction, a non-magnetic second spacer layer located between the second magnetization free layer and the second magnetization fixed layer, and two second magnet layers arranged in the first direction and sandwiching the second magnetization free layer in the first direction. Magnetic sensor. [Configuration 2] In each of the two first magnet layers, the magnetization direction of a half portion close to the first magnetization free layer is tilted toward the second direction more than the magnetization direction of the other half portion away from the first magnetization free layer, A magnetic sensor as described in configuration 1, wherein in each of the two second magnet layers, the magnetization direction of the half close to the second magnetization free layer is inclined toward the first direction more than the magnetization direction of the other half away from the second magnetization free layer. [Configuration 3] an angle between the average magnetization direction of the two first magnet layers and the second direction is between more than 0 degrees and less than 45 degrees; The angle between the average magnetization direction of the two second magnet layers and the first direction is greater than 0 degrees and is 4 degrees. 5 3. The magnetic sensor of claim 1 or 2, wherein the angle is between less than 100°. [Explanation of symbols]

[0039] 1 Magnetic sensor 2A, 2B First and second magnetic field sensing elements 3. Circuit Board 11A, 11B First and second magnetization pinned layers 12A, 12B First and second spacer layers 13A, 13B First and second magnetization free layers (first and second soft magnetic layers) 15A, 15B First and second upstream ends 16A, 16B First and second downstream ends 21A, 21B First and second upstream magnet layers 22A, 22B First and second downstream magnet layers 24A, 24B Center lines of the first and second magnetic free layers 25A, 25B Centerlines of the first and second upstream magnet layers 26A, 26B Centerlines of the first and second downstream magnet layers 27 Ferromagnetic layer 28 Antiferromagnetic layer 31A, 31B First and second upstream end regions 32A, 32B First and second downstream end regions 33A, 33B First and second upstream recesses 34A, 34B First and second downstream recesses 41A, 42A First shield layer 41B, 42B Second shield layer X first direction Y Second direction Z third direction

Claims

1. a first magnetic field sensing element having a magnetic field sensing axis substantially parallel to a first direction, two first magnet layers arranged in a second direction substantially perpendicular to the first direction, and a first magnetization free layer sandwiched between the two first magnet layers in the second direction and having a magnetization direction that rotates in response to an external magnetic field; a second magnetic field sensing element having a magnetic field sensing axis substantially parallel to the second direction, two second magnet layers arranged in the first direction, and a second magnetization free layer sandwiched between the two second magnet layers in the first direction and having a magnetization direction rotated by the external magnetic field; a substrate supporting the first magnetic field sensing element and the second magnetic field sensing element; a magnetic sensor manufacturing method including: a first magnet layer applying a bias magnetic field in the second direction to the first magnetization free layer; and a second magnet layer applying a bias magnetic field in the first direction to the second magnetization free layer; A method for manufacturing a magnetic sensor, comprising: applying an external magnetic field from a direction approximately equiangular to the first direction and the second direction while the two first magnet layers, the two second magnet layers, the first magnetization free layer, and the second magnetization free layer are supported on the substrate, thereby magnetizing the two first magnet layers and the two second magnet layers.

2. the first magnetic field sensing element includes the first magnetization free layer, a first magnetization fixed layer whose magnetization direction is fixed in the first direction, and a non-magnetic first spacer layer located between the first magnetization free layer and the first magnetization fixed layer; 2. The method for manufacturing a magnetic sensor as described in claim 1, wherein the second magnetic field detection element has the second magnetization free layer, a second magnetization fixed layer whose magnetization direction is fixed in the second direction, and a non-magnetic second spacer layer located between the second magnetization free layer and the second magnetization fixed layer.

3. 2. A method for manufacturing a magnetic sensor as described in claim 1, wherein a center line of the first magnetization free layer parallel to the second direction coincides with a center line of the two first magnet layers parallel to the second direction, and a center line of the second magnetization free layer parallel to the first direction coincides with a center line of the two second magnet layers parallel to the first direction.

4. the first magnetization free layer has a first upstream end and a first downstream end in the direction of application of the external magnetic field, the two first magnet layers include a first upstream magnet layer facing the first upstream end and a first downstream magnet layer facing the first downstream end, a center line of the first magnetization free layer parallel to the second direction is located between center lines of the two first magnet layers parallel to the second direction, a center line of the first upstream magnet layer parallel to the second direction is located on the near side in the direction of application of the external magnetic field relative to a center line of the first downstream magnet layer parallel to the second direction, the second magnetization free layer has a second upstream end and a second downstream end in the direction of application of the external magnetic field, the two second magnet layers include a second upstream magnet layer facing the second upstream end and a second downstream magnet layer facing the second downstream end, a center line of the second magnetization free layer parallel to the first direction is located between center lines of the two second magnet layers parallel to the first direction, 2. A method for manufacturing a magnetic sensor as described in claim 1, wherein a center line of the second upstream magnet layer parallel to the first direction is located forward of a center line of the second downstream magnet layer parallel to the first direction in the direction of application of the external magnetic field.

5. a dimension of the first magnet layer in the first direction being larger than a dimension of the first magnetization free layer in the first direction; The method for manufacturing a magnetic sensor according to claim 1 , wherein the dimension of the second magnet layer in the second direction is larger than the dimension of the second magnetization free layer in the second direction.

6. the first magnetization free layer has two triangular first end regions facing the two first magnet layers, The method for manufacturing a magnetic sensor according to claim 1 , wherein the second magnetization free layer has two triangular second end regions facing the two second magnet layers.

7. the two first magnet layers have first recesses that accommodate the first end regions; The method for manufacturing a magnetic sensor according to claim 6 , wherein the two second magnet layers have second recesses that accommodate the second end regions.

8. After forming the first magnetization fixed layer, the first magnetization fixed layer is heated while applying a magnetic field in the first direction to magnetize the first magnetization fixed layer; 3. The method for manufacturing a magnetic sensor according to claim 2, further comprising the steps of: forming the second magnetization fixed layer; heating the second magnetization fixed layer while applying a magnetic field in the second direction to magnetize the second magnetization fixed layer.

9. the dimensions of the two first magnet layers in the second direction are greater than the dimensions in the first direction; The method for manufacturing a magnetic sensor according to claim 1 , wherein the dimension of the two second magnet layers in the first direction is larger than the dimension of the two second magnet layers in the second direction.

10. at least one first shield layer elongated in the second direction and shielding the first magnetic field sensing element; at least one second shield layer elongated in the first direction and shielding the second magnetic field sensing element; and the at least one first shield layer includes two first shield layers sandwiching the first magnetic field sensing element in a third direction orthogonal to the first direction and the second direction; The method for manufacturing a magnetic sensor according to claim 1 , wherein the at least one second shield layer comprises two second shield layers sandwiching the second magnetic field sensing element in the third direction.

11. At least one first shield layer elongated in the second direction and shielding the first magnetic field detection element; at least one second shield layer elongated in the first direction and shielding the second magnetic field sensing element; and the at least one first shield layer includes two first shield layers sandwiching the first magnetic field sensing element in the second direction; The method for manufacturing a magnetic sensor according to claim 1 , wherein the at least one second shield layer comprises two second shield layers sandwiching the second magnetic field sensing element in the first direction.

12. The method for manufacturing a magnetic sensor according to claim 1 , wherein each of the two first magnet layers and the two second magnet layers is made of a hard magnetic material.

13. 12. A method for manufacturing a magnetic sensor according to claim 1, wherein each of the two first magnet layers and the two second magnet layers has a ferromagnetic layer and an antiferromagnetic layer, and each of the two first magnet layers and the two second magnet layers is locally heated while the external magnetic field is applied, thereby magnetizing each of the ferromagnetic layers.

14. a first magnetic field sensing element having a magnetic field sensing axis parallel to a first direction, a second magnetic field sensing element having a magnetic field sensing axis parallel to a second direction substantially perpendicular to the first direction, and a substrate supporting the first magnetic field sensing element and the second magnetic field sensing element; the first magnetic field detection element includes a first magnetization free layer whose magnetization direction rotates due to an external magnetic field, a first magnetization fixed layer whose magnetization direction is fixed in the first direction, a first non-magnetic spacer layer located between the first magnetization free layer and the first magnetization fixed layer, and two first magnet layers arranged in the second direction and sandwiching the first magnetization free layer in the second direction; the second magnetic field detection element includes a second magnetization free layer whose magnetization direction rotates due to an external magnetic field, a second magnetization fixed layer whose magnetization direction is fixed in the second direction, a non-magnetic second spacer layer located between the second magnetization free layer and the second magnetization fixed layer, and two second magnet layers arranged in the first direction and sandwiching the second magnetization free layer in the first direction; the two first magnet layers apply a bias magnetic field in the second direction to the first magnetization free layer, and the two second magnet layers apply a bias magnetic field in the first direction to the second magnetization free layer; A magnetic sensor, wherein in each of the two first magnet layers, the magnetization direction of the half close to the first magnetization free layer is inclined toward the second direction more than the magnetization direction of the other half away from the first magnetization free layer, and in each of the two second magnet layers, the magnetization direction of the half close to the second magnetization free layer is inclined toward the first direction more than the magnetization direction of the other half away from the second magnetization free layer, and the magnetization direction of the other half away from the first magnetization free layer of each of the two first magnet layers and the magnetization direction of the other half away from the second magnetization free layer of each of the two second magnet layers are parallel to each other.

15. an angle between the average magnetization direction of the two first magnet layers and the second direction is between more than 0 degrees and less than 45 degrees; The magnetic sensor of claim 14 , wherein an angle between an average magnetization direction of the two second magnet layers and the first direction is between more than 0 degrees and less than 45 degrees.

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