Magnetic sensor and its manufacturing method

Abstract

The magnetization direction of the magnetized fixed layer is fixed in the Z direction in which the magnetized free layer, non-magnetic layer, and magnetized fixed layer are stacked, and the magnetic sensor is provided in which the magnetization direction of the magnetized fixed layer is less likely to tilt from the Z direction. [Solution] The magnetic sensor 1 comprises at least one magnetic field sensing element 2 and at least one first soft magnetic layer 3. The at least one magnetic field sensing element 2 comprises a first magnetization fixed layer 63, a magnetization free layer 61 whose magnetization direction changes with respect to an external magnetic field, and a first non-magnetic layer 62. The first magnetization fixed layer 63, the magnetization free layer 61, and the first non-magnetic layer 62 are arranged in a first direction in the order of magnetization free layer 61, first non-magnetic layer 62, and first magnetization fixed layer 63, and the magnetization direction of the first magnetization fixed layer 63 is fixed in the first direction. The at least one first soft magnetic layer 3 faces at least one magnetic field sensing element 2 in the first direction.

Description

Technical Field

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

Background Art

[0002] A magnetic sensor using the magnetoresistance effect generally has a magnetization-free layer whose magnetization direction changes with respect to an external magnetic field, a magnetization-fixed layer whose magnetization direction is fixed, and a non-magnetic layer located between the magnetization-free layer and the magnetization-fixed layer. Patent Document 1 describes a magnetic sensor in which the magnetization direction of the magnetization-fixed layer is fixed in the stacking direction of the magnetization-free layer, the non-magnetic layer, and the magnetization-fixed layer.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the magnetic sensor described in Patent Document 1, although the magnetization direction of the magnetization-fixed layer is fixed in the stacking direction, the magnetization direction of the magnetization-fixed layer may tilt from the stacking direction due to an external magnetic field orthogonal to the stacking direction. The tilt of the magnetization direction of the magnetization-fixed layer may cause a decrease in the output of the magnetic sensor.

[0005] The present disclosure aims to provide a magnetic sensor in which the magnetization direction of the magnetization-fixed layer is fixed in the stacking direction of the magnetization-free layer, the non-magnetic layer, and the magnetization-fixed layer, and the magnetization direction of the magnetization-fixed layer is difficult to tilt from the stacking direction.

Means for Solving the Problems

[0006] The magnetic sensor of this disclosure comprises at least one magnetic field sensing element and at least one first soft magnetic layer. The at least one magnetic field sensing element comprises a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, and a first non-magnetic layer. The first magnetization fixed layer, the magnetization free layer, and the first non-magnetic layer are arranged in a first direction in the order of magnetization free layer, first non-magnetic layer, and first magnetization fixed layer, and the magnetization direction of the first magnetization fixed layer is fixed in the first direction. The at least one first soft magnetic layer faces at least one magnetic field sensing element in the first direction. [Effects of the Invention]

[0007] According to this disclosure, the magnetization direction of the magnetized fixed layer is fixed in the stacking direction of the magnetized free layer, the non-magnetic layer, and the magnetized fixed layer, and a magnetic sensor can be provided in which the magnetization direction of the magnetized fixed layer is less likely to tilt from the stacking direction. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram of the magnetic sensor according to the first embodiment. [Figure 2] This is a schematic diagram of the magnetic sensor according to the second embodiment. [Figure 3] This is a schematic diagram of the magnetic sensor according to the third embodiment. [Figure 4] This is a schematic diagram of the magnetic sensor according to the fourth embodiment. [Figure 5] This is a schematic diagram of the magnetic sensor according to the fifth embodiment. [Figure 6] This is a schematic diagram of the magnetic sensor according to the sixth embodiment and comparative example. [Figure 7] This is a schematic diagram of the magnetic sensor according to the seventh embodiment. [Figure 8] This is a schematic diagram of the magnetic sensor according to the eighth embodiment. [Figure 9] This is a schematic diagram of the magnetic sensor according to the ninth embodiment. [Modes for carrying out the invention]

[0009] Several embodiments of the present disclosure will be described with reference to the drawings. In the following description and drawings, the direction in which the multiple layers of the laminate 6 are stacked (first direction) is referred to as the Z direction. The direction from the laminate 6 toward the upper electrode layer 5 is referred to as the +Z direction, and the direction from the laminate 6 toward the lower electrode layer 7 or the substrate is referred to as the -Z direction. The direction perpendicular to the Z direction is referred to as the X direction. For convenience, the X direction is shown in the drawings, but the X direction may be any direction perpendicular to the Z direction. Unless otherwise specified, in the drawings, white arrows indicate the magnetization direction of the first magnetization fixed layer 63 and the second magnetization fixed layer 65, thick lines with arrows indicate the magnetization direction of the magnetization free layer 61 in the absence of an external magnetic field (hereinafter referred to as the zero magnetic field state), and dashed lines with arrows conceptually indicate magnetic flux (external magnetic field).

[0010] (First embodiment) Figure 1 shows a schematic configuration of a magnetic sensor 1 according to the first embodiment. Figure 1(a) is a front view of the magnetic sensor 1, and Figure 1(b) is a top view of the magnetic sensor 1 viewed from the Z direction. The magnetic sensor 1 includes a magnetic field sensing element 2, and a first soft magnetic layer 3 and a second soft magnetic layer 4 sandwiching the magnetic field sensing element 2 in the Z direction. The magnetic field sensing element 2 includes a silicon substrate (not shown), a laminate 6, and upper and lower electrode layers 5 and 7 that supply sense current to the laminate 6. The upper electrode layer 5, the laminate 6, and the lower electrode layer 7 are arranged on the substrate in the order of upper electrode layer 5, laminate 6, and lower electrode layer 7 in the -Z direction. Although not shown, other layers are provided between the lower electrode layer 7 and the substrate, and the lower electrode layer 7 is separated from the substrate. The upper electrode layer 5 and the lower electrode layer 7 can be formed from a laminate film made of conductors such as Ta, Cu, or Ru. The first soft magnetic layer 3 and the second soft magnetic layer can be formed from NiFe or the like.

[0011] The laminate 6 has a magnetization-free layer 61, a first non-magnetic layer 62, a first magnetization-fixed layer 63, a second magnetization-fixed layer 65, and an intermediate layer 64. These layers are arranged in the -Z direction from the upper electrode layer 5 toward the lower electrode layer 7 in the order of magnetization-free layer 61, first non-magnetic layer 62, first magnetization-fixed layer 63, intermediate layer 64, and second magnetization-fixed layer 65, with adjacent layers touching each other. These layers may also be stacked in the reverse direction; specifically, they may be arranged in the -Z direction from the upper electrode layer 5 toward the lower electrode layer 7 in the order of second magnetization-fixed layer 65, intermediate layer 64, first magnetization-fixed layer 63, first non-magnetic layer 62, and magnetization-free layer 61.

[0012] The magnetization free layer 61 is a magnetic layer whose magnetization direction changes in response to an external magnetic field. The magnetization free layer 61 can be formed from ferromagnetic materials such as Ni, Fe, or Co, alloys consisting of two or more of these, or alloys obtained by adding B or Si to the alloy to make it amorphous. In a zero magnetic field state, the magnetization direction of the magnetization free layer 61 is perpendicular to the Z direction.

[0013] The first non-magnetic layer 62 is made of an insulating layer such as MgO or Al2O3, and the magnetic field sensing element 2 in this embodiment operates as a tunnel magnetoresistance effect element (TMR element). The first non-magnetic layer 62 may also be made of a non-magnetic metal layer such as copper or silver, in which case the magnetic field sensing element 2 operates as a giant magnetoresistance effect element (GMR element). TMR elements tend to produce higher output than GMR elements.

[0014] The first magnetization fixed layer 63 is a magnetic layer whose magnetization direction is fixed in the Z direction. The first magnetization fixed layer 63 is magnetically coupled to the second magnetization fixed layer 65 by a synthetic antiferromagnetic coupling via an intermediate layer 64. The magnetization direction of the first magnetization fixed layer 63 is fixed in the opposite direction to the magnetization direction of the second magnetization fixed layer 65. The first magnetization fixed layer 63 and the second magnetization fixed layer 65 can be formed from multilayer films of Co and Pt, or from materials with strong perpendicular magnetic anisotropy such as multilayer films of Co and Pd, or multilayer films of Co and Ni. The intermediate layer 64 is made of a non-magnetic metal such as ruthenium that produces RKKY (Ruderman-Kittel-Kasuya-Yosida) bonds. A multilayer film consisting of a first magnetization fixed layer 63, an intermediate layer 64, and a second magnetization fixed layer 65 is also called a SAF (Synthetic Antiferromagnetic) structure. Because the magnetization directions of the first magnetization fixed layer 63 and the second magnetization fixed layer 65 are oriented in opposite directions, the leakage magnetic field applied from the first magnetization fixed layer 63 to the magnetization free layer 61 can be suppressed. The magnetization amount of the first magnetization fixed layer 63 and the magnetization amount of the second magnetization fixed layer 65 can be made to be approximately the same. In Figure 1, the first magnetization fixed layer 63 is magnetized in the +Z direction and the second magnetization fixed layer 65 is magnetized in the -Z direction, but the first magnetization fixed layer 63 may be magnetized in the -Z direction and the second magnetization fixed layer 65 may be magnetized in the +Z direction.

[0015] When an external magnetic field having a component in the Z direction is applied to the magnetized free layer 61, the magnetization direction of the magnetized free layer 61 tilts in the Z direction. As a result, the angle between the magnetization direction of the magnetized free layer 61 and the magnetization direction of the first magnetized fixed layer 63 changes, and the electrical resistance of the laminate 6 changes due to the magnetoresistance effect. By detecting the change in the electrical resistance of the laminate 6, the strength of the Z-direction component of the external magnetic field can be measured. In this way, the magnetic sensor 1 of this embodiment detects a magnetic field in the Z direction.

[0016] The first soft magnetic layer 3 and the second soft magnetic layer 4 face the magnetic field detection element 2 (or the laminate 6) in the Z direction. The magnetic field detection element 2 (or the laminate 6) is located between the first soft magnetic layer 3 and the second soft magnetic layer 4 in the Z direction. Either the first soft magnetic layer 3 or the second soft magnetic layer 4 may be omitted. The first soft magnetic layer 3 and the second soft magnetic layer 4 absorb the magnetic flux in the X direction, thereby attenuating the external magnetic field in the X direction applied to the laminate 6. Although the magnetization direction of the first magnetization fixing layer 63 is fixed in the Z direction, when a strong magnetic field is applied to the first magnetization fixing layer 63 from a direction other than the Z direction, the magnetization direction of the first magnetization fixing layer 63 tilts from the Z direction, which may cause the output of the magnetic sensor 1 to decrease. Also, the magnetization direction of the magnetization free layer 61 is determined by the combined magnetic field of a magnetic field other than the Z direction and the magnetic field in the Z direction. Therefore, if the fluctuation in the intensity of the magnetic field applied from a direction other than the Z direction is large, even if the magnetic field intensity in the Z direction is the same, the tilt of the magnetization direction of the magnetization free layer 61 with respect to the Z direction changes, and the sensitivity of the magnetic sensor 1 may fluctuate. In the present embodiment, since the first soft magnetic layer 3 and the second soft magnetic layer 4 act as a shield against the magnetic field applied from a direction other than the Z direction, the above-mentioned possibility can be reduced.

[0017] As shown in FIG. 1(b), the laminate 6 including the magnetization free layer 61 has an elliptical shape having a major axis C1 in an arbitrary cross section orthogonal to the Z direction. The shape of the laminate 6 is not limited as long as it has the major axis C1, and it can take any shape such as a rectangle, a shape in which semicircles are connected to both short sides of the rectangle, or a shape in which the four corners of the rectangle are rounded or chamfered. By having the major axis C1, a shape anisotropy magnetic field in a direction parallel to the major axis C1 is generated in the magnetization free layer 61. This magnetic field acts as a bias magnetic field for the magnetization free layer 61. The bias magnetic field is a magnetic field that directs the magnetization direction of the magnetization free layer 61 in a predetermined direction in the zero magnetic field state, and the direction and intensity are constant. The magnetization free layer 61 is magnetized in a direction parallel to the major axis C1 in the zero magnetic field state by the bias magnetic field. Since the generation of a large number of magnetic domains in the magnetization free layer 61 is suppressed, the output with respect to the magnetic field in the Z direction tends to be stable.

[0018] On the one hand, when an external magnetic field is applied in the same direction as the bias magnetic field, the magnetization direction of the magnetization free layer 61 becomes less likely to tilt in the Z direction, and the sensitivity to the magnetic field in the Z direction decreases. When the external magnetic field is applied in the opposite direction to the bias magnetic field, the magnetization direction of the magnetization free layer 61 becomes more likely to tilt in the Z direction, and the sensitivity to the Z magnetic field increases. As a result, the output signal is likely to become unstable with respect to the direction of the external magnetic field. Therefore, it is preferable to suppress as much as possible the application of an external magnetic field in the same direction or the opposite direction to the bias magnetic field to the magnetization free layer 61. Here, the external magnetic field referred to here is an external magnetic field other than the detection target, and generally, the direction and intensity can change with time. The external magnetic field is a magnetic field other than the Z direction and does not include the bias magnetic field.

[0019] Generally, the shielding function of a magnetic material is generated by magnetization of the magnetic material by an external magnetic field. That is, when an external magnetic field is applied, magnetic poles are generated at the ends of the magnetic material in the direction of application of the external magnetic field. Then, a part of the magnetic field generated from the magnetic poles acts to cancel out the external magnetic field, so that the external magnetic field around the magnetic material is shielded. The magnetic poles are generated by a relatively weak external magnetic field in the long axis direction (easy magnetization axis direction) of the magnetic material, and the magnetic material exhibits strong shielding properties (effect of canceling out the external magnetic field). On the other hand, in the short axis direction (difficult magnetization axis direction) of the magnetic material, since the magnetic material is difficult to be magnetized and magnetic poles are difficult to be generated, the shielding property is relatively weak.

[0020] In this embodiment, at least one of the first soft magnetic layer 3 and the second soft magnetic layer 4 has a major axis C2, and the direction of the bias magnetic field applied to the magnetization free layer 61 can be parallel to the major axis C2 of at least one of the first soft magnetic layer 3 and the second soft magnetic layer 4. In other words, the magnetization free layer 61 has a major axis C1, at least one of the first soft magnetic layer 3 and the second soft magnetic layer 4 has a major axis C2, and the major axes C1 and C2 can be parallel. Alternatively, both the first soft magnetic layer 3 and the second soft magnetic layer 4 have major axes C2 in the same direction, and the direction of the bias magnetic field applied to the magnetization free layer 61 can be parallel to the major axes C2 of the first soft magnetic layer 3 and the second soft magnetic layer 4. In other words, the magnetization free layer 61 has a major axis C1, and both the first soft magnetic layer 3 and the second soft magnetic layer 4 have major axes C2 in the same direction, and the major axes C1 and C2 can be made parallel. Furthermore, the shapes of the first soft magnetic layer 3 and the second soft magnetic layer 4 are not limited as long as they have a major axis C2, and can take any shape, such as a rectangle, a rectangle with semicircles connected to both short sides, or a rectangle with rounded or cut corners.

[0021] The means for applying the bias magnetic field is not limited to the shape of the magnetized free layer 61 itself, but may be a magnet provided on the side of the magnetized free layer 61, or a magnet installed outside the magnetic sensor 1. Furthermore, the means for applying the bias magnetic field can be omitted. In this case, the magnetized free layer 61 can have a shape that does not have a major axis when viewed from the Z direction (circular, square, etc.), and the magnetization direction does not have to be aligned in the zero magnetic field state. The first soft magnetic layer 3 and the second soft magnetic layer 4 can also have a shape that does not have a major axis when viewed from the Z direction (circular, square, etc.).

[0022] The first soft magnetic layer 3 and the second soft magnetic layer 4 also have the effect of strengthening the magnetic field in the Z direction. Magnetic flux around the first soft magnetic layer 3 (or the second soft magnetic layer 4) flows toward the first soft magnetic layer 3 (or the second soft magnetic layer 4) and is emitted into the surroundings from the second soft magnetic layer 4 (or the first soft magnetic layer 3). The first soft magnetic layer 3 and the second soft magnetic layer 4 have a magnetic collecting effect with respect to the magnetic field in the Z direction and act as a yoke, thereby increasing the output of the magnetic sensor 1. Thus, in this embodiment, the first soft magnetic layer 3 and the second soft magnetic layer 4 act as both a shield and a yoke depending on the direction of the magnetic field. For example, in magnetoresistive memory (MRAM), it is important to protect the recorded data, so the soft magnetic material provided around the memory section acts as a shield regardless of the direction of the magnetic field. The magnetic sensor 1 of this embodiment has significantly different functions of the soft magnetic layers (first soft magnetic layer 3 and second soft magnetic layer 4) compared to other applications that use the magnetoresistive effect.

[0023] Furthermore, when using a conventional magnetic sensor, in which the magnetization direction of the magnetized free layer changes in the in-plane direction (X direction), together with a yoke to detect a magnetic field in the Z direction, it is necessary to bend the Z-direction magnetic field in the in-plane direction with the yoke and apply it to the magnetized free layer. For this reason, the laminate is positioned offset from the yoke when viewed from the Z direction. In this embodiment, since the Z-direction magnetic field is detected without changing its orientation, the first soft magnetic layer 3 and the second soft magnetic layer 4 can be positioned directly above or below the laminate 6 in the Z direction. That is, when viewed from the Z direction, the center of the magnetized free layer 61 may overlap with the first soft magnetic layer 3 and the second soft magnetic layer 4, making it easy to miniaturize the magnetic sensor 1.

[0024] (Second embodiment) Figure 2 shows a schematic configuration of the magnetic sensor 1 according to the second embodiment. The configuration and effects, which are not described, are the same as those of the first embodiment. The laminate 6 has a magnetization free layer 61, a first non-magnetic layer 62, a first magnetization fixed layer 63, a second magnetization fixed layer 65, and a second non-magnetic layer 66. These layers are arranged in the -Z direction from the upper electrode layer 5 toward the lower electrode layer 7 in the order of the second magnetization fixed layer 65, the second non-magnetic layer 66, the magnetization free layer 61, the first non-magnetic layer 62, and the first magnetization fixed layer 63, with adjacent layers touching each other. These layers may also be laminated in the reverse direction. Specifically, they may be arranged in the -Z direction from the upper electrode layer 5 toward the lower electrode layer 7 in the order of the first magnetization fixed layer 63, the first non-magnetic layer 62, the magnetization free layer 61, the second non-magnetic layer 66, and the second magnetization fixed layer 65. The magnetized free layer 61, the first non-magnetic layer 62, the first magnetized fixed layer 63, and the second magnetized fixed layer 65 can be configured in the same manner as in the first embodiment. The second non-magnetic layer 66 is provided to magnetically separate the magnetized free layer 61 and the second magnetized fixed layer 65, and is not limited to being a non-magnetic layer; it may be formed from any metal such as copper or an insulator such as Al2O3.

[0025] The magnetization direction of the second magnetization fixed layer 65 is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer 63. Therefore, in this embodiment as well, the leakage magnetic field applied to the magnetization free layer 61 can be suppressed. In Figure 2, the first magnetization fixed layer 63 is magnetized in the +Z direction and the second magnetization fixed layer 65 is magnetized in the -Z direction, but the first magnetization fixed layer 63 may be magnetized in the -Z direction and the second magnetization fixed layer 65 may be magnetized in the +Z direction. In order to make the magnetization directions of the first magnetization fixed layer 63 and the second magnetization fixed layer 65 opposite to each other, the anisotropic magnetic field Hk1 of the first magnetization fixed layer 63 and the anisotropic magnetic field Hk2 of the second magnetization fixed layer 65 can be made different. For example, if Hk1 > Hk2, first a magnetic field H1 in the Z direction that is greater than Hk1 is applied to the first magnetization fixed layer 63 and the second magnetization fixed layer 65. Since H1 > Hk1 > Hk2, the first magnetization fixed layer 63 and the second magnetization fixed layer 65 are magnetized in the same direction. Next, a magnetic field H2, which is Hk1 > H2 > Hk2 and is in the opposite direction to H1, is applied to the first magnetization fixed layer 63 and the second magnetization fixed layer 65. The magnetization direction of the first magnetization fixed layer 63 remains unchanged, while only the magnetization direction of the second magnetization fixed layer 65 is reversed.

[0026] (Third embodiment) Figure 3 shows a schematic configuration of the magnetic sensor 1 according to the third embodiment. The configuration and effects, which are not described, are the same as in the first embodiment. The laminate 6 has a magnetization free layer 61, a first non-magnetic layer 62, a first magnetization fixed layer 63, and an antiferromagnetic layer 67. These layers are arranged in the order of magnetization free layer 61, first non-magnetic layer 62, first magnetization fixed layer 63, and antiferromagnetic layer 67 in the -Z direction from the upper electrode layer 5 to the lower electrode layer 7, and adjacent layers are in contact with each other. These layers may be laminated in reverse direction, specifically, they may be arranged in the order of antiferromagnetic layer 67, first magnetization fixed layer 63, first non-magnetic layer 62, and magnetization free layer 61 in the -Z direction from the upper electrode layer 5 to the lower electrode layer 7. The magnetization free layer 61, the first non-magnetic layer 62, and the first magnetization fixed layer 63 can be configured in the same way as in the first embodiment. The antiferromagnetic layer 67 can be formed from IrMn, or from other antiferromagnetic materials such as PtMn or FeRh.

[0027] The first magnetization fixed layer 63 can be magnetized by applying an external magnetic field while annealing (heating). The first magnetization fixed layer 63 is exchange-coupled with the antiferromagnetic layer 67 and is fixed in the same direction as the magnetization direction during annealing. If a strong magnetic field in the Z direction opposite to the magnetization direction of the first magnetization fixed layer 63 is applied, the magnetization direction of the first magnetization fixed layer 63 may temporarily reverse. If the magnetization direction of the first magnetization fixed layer 63 remains reversed, the slope of the output may reverse (for example, an upward-sloping output curve may become a downward-sloping output curve). However, in a zero-magnetic field state, the magnetization direction of the first magnetization fixed layer 63 returns to its original state. For this reason, the magnetization direction of the first magnetization fixed layer 63 is more stable in a zero-magnetic field state, and output reversal is less likely to occur. In Figure 3, the antiferromagnetic layer 67 and the first magnetization fixed layer 63 are magnetized in the +Z direction, but they may also be magnetized in the -Z direction.

[0028] (Fourth embodiment) Figure 4 shows a schematic configuration of the magnetic sensor 1 according to the fourth embodiment. The configuration and effects, which are not described, are the same as those of the first embodiment. The laminate 6 of this embodiment has a configuration that combines the first and third embodiments. The laminate 6 has a magnetization free layer 61, a first non-magnetic layer 62, a first magnetization fixed layer 63, an intermediate layer 64 made of a non-magnetic metal such as ruthenium that causes RKKY bonding, a second magnetization fixed layer 65, and an antiferromagnetic layer 67. These layers are arranged in the order of magnetization free layer 61, first non-magnetic layer 62, first magnetization fixed layer 63, intermediate layer 64, second magnetization fixed layer 65, and antiferromagnetic layer 67 in the -Z direction from the upper electrode layer 5 to the lower electrode layer 7, and adjacent layers are in contact with each other. These layers may be stacked in reverse order. Specifically, they may be arranged in the -Z direction from the upper electrode layer 5 toward the lower electrode layer 7 in the order of antiferromagnetic layer 67, second magnetization fixed layer 65, intermediate layer 64, first magnetization fixed layer 63, first non-magnetic layer 62, and magnetization free layer 61.

[0029] The SAF structure fixes the magnetization direction of the first magnetization fixed layer 63 in the opposite direction to the magnetization direction of the second magnetization fixed layer 65. Furthermore, the magnetization direction of the second magnetization fixed layer 65 is fixed in the same direction as the magnetization direction during annealing through exchange coupling with the antiferromagnetic layer 67. This embodiment achieves the effects of both the first and third embodiments. Specifically, the SAF structure suppresses the leakage magnetic field applied to the magnetization free layer 61, and the antiferromagnetic layer 67 stabilizes the magnetization direction of the second magnetization fixed layer 65 in a zero magnetic field state.

[0030] (Fifth embodiment) Figure 5 shows a schematic configuration of the magnetic sensor 1 according to the fifth embodiment. The configuration and effects, which are not described, are the same as those of the first embodiment. The configuration of the laminate 6 in this embodiment is the same as that of the first embodiment, but the magnetization direction of the magnetized free layer 61 is vortex-shaped in a plane perpendicular to the Z direction in the zero magnetic field state. The magnetization state of the magnetized free layer 61 in the zero magnetic field state is determined by the balance between the exchange energy and magnetostatic energy of the magnetized free layer 61, and generally, a larger saturation magnetization makes it easier for a vortex shape to occur. In the zero magnetic field state, the center of the vortex, called the core, is located at the center of the magnetized free layer 61, and the magnetization direction traces concentric circles centered on the core. When an external magnetic field in the Z direction is applied, the magnetization direction is tilted overall in the Z direction, so the same magnetoresistance effect as in the first embodiment can be obtained. In this embodiment, since the magnetized free layer 61 is vortex-shaped in the zero magnetic field state, it is easy to suppress fluctuations in sensitivity when subjected to magnetic fields other than the Z direction. This embodiment can be combined with the second to fourth embodiments, specifically, the magnetization direction of the magnetization free layer 61 in the second to fourth embodiments can be made spiral-shaped.

[0031] (Sixth embodiment) Figure 6(a) shows a schematic configuration of the magnetic sensor 1 according to the sixth embodiment. The configuration and effects, which are not described, are the same as those of the first embodiment. The magnetic sensor 1 of this embodiment has a plurality of magnetic field detection elements 2 of the fifth embodiment, that is, magnetic field detection elements 2 in which the magnetization direction of the magnetization free layer 61 forms a vortex shape in the zero magnetic field state. The configuration of each of the plurality of magnetic field detection elements 2 may be the same as that of the magnetic field detection element 2 of the fifth embodiment. The plurality of magnetic field detection elements 2 are connected in series. The number of plurality of magnetic field detection elements 2 is not limited, but for convenience, Figure 6 shows two magnetic field detection elements 2 (hereinafter referred to as the first magnetic field detection element 2A and the second magnetic field detection element 2B). The plurality of magnetic field detection elements 2 are facing one first soft magnetic layer 3 in the Z direction. The white arrows indicate the magnetization direction of the core in the zero magnetic field state of the magnetization free layer 61.

[0032] Figure 6(b) shows the schematic configuration of the comparative example magnetic sensor 101, and Figure 6(c) shows the magnetization curve of the magnetized free layer 61. The magnetization direction of the core of the magnetized free layer 61 is either the +Z direction or the -Z direction in the zero magnetic field state, and the magnetization curve of the magnetized free layer 61 (a curve with magnetic field strength on the horizontal axis and magnetization on the vertical axis) shifts left or right depending on the orientation of the core. For example, if the magnetization curve shifts to the left when the magnetization direction of the core is in the +Z direction, then the magnetization curve shifts to the right when the magnetization direction of the core is in the -Z direction. Such magnetic characteristics reduce the accuracy of the output of the magnetic sensor 1.

[0033] In this embodiment, the magnetization directions of the cores of the first magnetic field sensing element 2A and the second magnetic field sensing element 2B (a portion and the remainder of the multiple magnetic field sensing elements 2) are opposite to each other. As a result, the shifts in the magnetization curves of the magnetization free layer 61 of the first magnetic field sensing element 2A and the magnetization free layer 61 of the second magnetic field sensing element 2B are canceled out, improving the accuracy of the output of the magnetic sensor 1. As can be understood from this, in Figure 6(a), the same number of magnetic field sensing elements 2 can be arranged in the left and right regions of the first soft magnetic layer 3. More generally, the same number of magnetic field sensing elements 2 can be arranged on both sides of a plane P that includes a center line C parallel to the Z direction of the first soft magnetic layer 3.

[0034] An external magnetic field can be applied in the X direction to reverse the magnetization direction of the core of the first magnetic field sensing element 2A and the core of the second magnetic field sensing element 2B. The external magnetic field in the X direction is bent in the +Z direction by the first soft magnetic layer 3, so that the first magnetic field sensing element 2A is subjected to a magnetic field containing a component in the +Z direction, and the second magnetic field sensing element 2B is subjected to a magnetic field containing a component in the -Z direction. If the Z component of the external magnetic field is sufficiently large, the core temporarily disappears, and when the external magnetic field is removed, the core reappears. The direction of magnetization of the core is determined by the Z component of the last applied magnetic field. In the example shown in Figure 6(a), the magnetization direction of the core of the first magnetic field sensing element 2A is in the +Z direction, and the magnetization direction of the core of the second magnetic field sensing element 2B is in the -Z direction.

[0035] The plane P can be oriented in any direction as long as it is parallel to the Z direction. By applying an external magnetic field from a direction perpendicular to the plane P, a magnetic field containing a +Z component can be applied to some of the magnetic field sensing elements 2, and a magnetic field containing a -Z component can be applied to the remaining magnetic field sensing elements 2. The plane P can also be determined by the arrangement of multiple magnetic field sensing elements 2; specifically, the plane P can be determined such that multiple magnetic field sensing elements 2 are divided in half by the plane P. Figure 6 shows only the first soft magnetic layer 3, but if the first soft magnetic layer 3 and the second soft magnetic layer 4 are provided, the first magnetic field sensing element 2A and the second magnetic field sensing element 2B can be positioned offset from the Z-direction center of the first soft magnetic layer 3 and the second soft magnetic layer 4. This makes it possible to apply a magnetic field containing a +Z component and a magnetic field containing a -Z component to the first magnetic field sensing element 2A and the second magnetic field sensing element 2B, respectively.

[0036] (Seventh Embodiment) Figure 7 shows a schematic configuration of the magnetic sensor 1 according to the seventh embodiment. The configuration and effects, which are not described, are the same as in the first embodiment. The laminate 6 has a magnetization free layer 61, a first non-magnetic layer 62, and a first magnetization fixed layer 63. These layers are arranged in the order of magnetization free layer 61, first non-magnetic layer 62, and first magnetization fixed layer 63 in the -Z direction from the upper electrode layer 5 to the lower electrode layer 7, and adjacent layers are in contact with each other. These layers may be stacked in reverse order, specifically, they may be arranged in the order of first magnetization fixed layer 63, first non-magnetic layer 62, and magnetization free layer 61 in the -Z direction from the upper electrode layer 5 to the lower electrode layer 7. This embodiment omits the second magnetization fixed layer 65 and the second non-magnetic layer 66 in the first embodiment, and the other configurations are the same as in the first embodiment. This embodiment simplifies the configuration of the laminate 6, leading to a cost reduction of the magnetic sensor 1.

[0037] (Eighth embodiment) Figure 8 shows a schematic configuration of the magnetic sensor 1 according to the eighth embodiment. The magnetic sensor 1 of this embodiment is a combination of the magnetic field detection elements 2 of each embodiment described above as a half-bridge. The magnetic sensor 1 has first and second element units 11 and 12, each containing at least one magnetic field detection element 2. In one embodiment, the first and second element units 11 and 12 each contain an array in which multiple magnetic field detection elements 2 are connected in series. The first element unit 11 and the second element unit 12 form a set 15 connected in series, with one end of the set 15 connected to a power supply VDD and the other end connected to ground (GND). The magnetic sensor 1 has an output unit 17 located between the first element unit 11 and the second element unit 12. The magnetization direction of the first magnetization fixed layer 63 of the first element unit 11 and the magnetization direction of the first magnetization fixed layer 63 of the second element unit 12 are opposite to each other. The first soft magnetic layer 3 (shown by a dashed line for convenience) and the second soft magnetic layer 4 cover all of the first and second element units 11 and 12 in the Z direction, but the first element unit 11 and the second element unit 12 may be covered individually, or each magnetic field sensing element 2 may be covered individually.

[0038] In the eighth embodiment, the magnetic sensor 1 (third and fourth embodiments) in which the magnetic field sensing element 2 is equipped with an antiferromagnetic layer 67 can be manufactured using laser annealing. Specifically, for example, in the film configuration shown in Figure 3, a magnetic field in the Z direction (first direction) is applied while irradiating the first element unit 11 with laser light to magnetize the first magnetization fixing layer 63 of the first element unit 11, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. Next, while irradiating the second element unit 12 with laser light, for example, a magnetic field in the opposite direction (second direction) to the magnetic field applied to the first element unit 11 is applied to magnetize the first magnetization fixing layer 63 of the second element unit 12, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. In the film configuration shown in Figure 4, the second magnetization fixing layer 65 is magnetized, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. In laser annealing, laser light is irradiated at multiple locations, but considering the precision of the element unit formation, it is preferable that the spacing between the laser light irradiation positions be about 5 μm or more, preferably about 10 μm or more.

[0039] In this embodiment, the magnetized fixed layer is magnetized using laser annealing, but the heating method is not limited to laser light, as long as the first element unit 11 and the second element unit 12 can be locally heated. For example, heating wiring may be provided near the first element unit 11 and the second element unit 12, and the heating wiring may be energized to generate heat, thereby heating the first element unit 11 and the second element unit 12.

[0040] (Ninth embodiment) Figure 9 shows a schematic configuration of the magnetic sensor 1 according to the ninth embodiment. The magnetic sensor 1 of this embodiment is a combination of the magnetic field detection elements 2 of each embodiment described above as a full bridge. The magnetic sensor 1 has first to fourth element units 11 to 14, each containing at least one magnetic field detection element 2. In one embodiment, the first to fourth element units 11 to 14 each contain an array in which multiple magnetic field detection elements 2 are connected in series. The first element unit 11 and the second element unit 12 form a first set 16A connected in series, and the third element unit 13 and the fourth element unit 14 form a second set 16B connected in series, with one end of the first set 16A and the second set 16B connected to the power supply VDD and the other end connected to ground (GND). The first element unit 11 and the fourth element unit 14 are located on the side of the power supply VDD, and the second element unit 12 and the third element unit 13 are located on the ground side (GND). The magnetic sensor 1 has a differencer 18 that calculates the difference between the output between the first element unit 11 and the second element unit 12 and the output between the third element unit 13 and the fourth element unit 14. The magnetization direction of the first magnetization fixed layer 63 of the first element unit 11 and the third element unit 13 is the same, and the magnetization direction of the first magnetization fixed layer 63 of the second element unit 12 and the fourth element unit 14 is opposite to the magnetization direction of the first magnetization fixed layer 63 of the first element unit 11 and the third element unit 13. The first soft magnetic layer 3 (shown by a dashed line for convenience) and the second soft magnetic layer 4 cover all of the first to fourth element units 11 to 14 in the Z direction, but the first to fourth element units 11 to 14 may be covered individually, or each magnetic field detection element 2 may be covered individually.

[0041] The voltage drop across each element unit 11-14 is approximately proportional to the electrical resistance of the element units 11-14. Therefore, if the electrical resistances of the first to fourth element units 11-14 are R1-R4 respectively, then the midpoint voltage V1 is V1 = R2 / (R1+R2) × VDD, and the midpoint voltage V2 is V2 = R3 / (R3+R4) × VDD. By calculating the difference V1-V2 between the midpoint voltages V1 and V2 using the differencer 18, twice the sensitivity can be obtained compared to detecting the midpoint voltages V1 and V2 directly. Furthermore, even if the midpoint voltages V1 and V2 are offset, the effect of the offset can be eliminated by detecting the difference.

[0042] In the ninth embodiment of the magnetic sensor 1, the magnetic sensor 1 (third and fourth embodiments) in which the magnetic field detection element 2 is equipped with an antiferromagnetic layer 67 can be manufactured using laser annealing. Specifically, for example, in the case of the film configuration shown in Figure 3, a magnetic field in the Z direction (first direction) is applied while irradiating the first and third element units 11 and 13 with laser light to magnetize the first magnetization fixing layer 63 of the first and third element units 11 and 13, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. Next, while irradiating the second and fourth element units 12 and 14 with laser light, a magnetic field in the opposite direction (second direction) to the magnetic field applied to the first magnetization fixing layer 63 of the first and third element units 11 and 13 is applied to magnetize the first magnetization fixing layer 63 of the second and fourth element units 12 and 14, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. In the film configuration shown in Figure 4, the second magnetization fixing layer 65 is magnetized, and the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 67. In this embodiment as well, the heating method is not limited to laser light. See the eighth embodiment for details. In this embodiment as well, it is preferable that the spacing between the laser light irradiation positions be about 5 μm or more, preferably about 10 μm or more.

[0043] In the eighth and ninth embodiments, the above-described SAF structure can also be used to reverse the magnetization direction of the first magnetization fixed layer 63 of some element units and other element units. For example, in the eighth embodiment, when using the magnetic field sensing element 2 of the first embodiment, the film thickness of the first magnetization fixed layer 63 in the first element unit 11 can be made greater than that of the second magnetization fixed layer 65, and the film thickness of the first magnetization fixed layer 63 in the second element unit 12 can be made smaller than that of the second magnetization fixed layer 65. However, this configuration complicates the manufacturing process and makes it difficult to suppress leakage magnetic fields because the film configuration, including the film thickness, differs between the first element unit 11 and the second element unit 12. By using the third and fourth embodiments which use an antiferromagnetic layer 67, all magnetic field sensing elements 2 can have the same film configuration, including the film thickness, even when a bridge is assembled.

[0044] (Note) This specification includes the following disclosures. [Configuration 1] It comprises at least one magnetic field sensing element and at least one first soft magnetic layer, The aforementioned at least one magnetic field sensing element includes a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, and a first non-magnetic layer. A magnetic sensor in which the first magnetization-fixed layer, the magnetization-free layer, and the first non-magnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, and the first magnetization-fixed layer, the magnetization direction of the first magnetization-fixed layer is fixed in the first direction, and the at least one first soft magnetic layer faces the at least one magnetic field sensing element in the first direction. [Configuration 2] The magnetic sensor according to configuration 1, having at least one second soft magnetic layer facing the at least one magnetic field sensing element in the first direction, wherein the at least one magnetic field sensing element is located between the at least one first soft magnetic layer and the at least one second soft magnetic layer. [Configuration 3] The magnetic sensor according to configuration 2, wherein the magnetization free layer has a long axis, at least one of the first soft magnetic layer and the second soft magnetic layer has a long axis, and the long axis of the magnetization free layer and the long axis of at least one of the first soft magnetic layer and the second soft magnetic layer are parallel. [Structure 4] The magnetic sensor according to any one of configurations 1 to 3, wherein the first non-magnetic layer is an insulating layer. [Composition 5] The at least one magnetic field sensing element comprises a second magnetization-fixed layer and an intermediate layer made of a non-magnetic metal, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the second magnetization-fixed layer, and the intermediate layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, the intermediate layer, and the second magnetization-fixed layer. The magnetic sensor according to any one of configurations 1 to 4, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer. [Composition 6] The at least one magnetic field sensing element comprises a second magnetization-fixed layer and a second non-magnetic layer, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the second magnetization-fixed layer, and the second non-magnetic layer are arranged in the first direction in the order of the second magnetization-fixed layer, the second non-magnetic layer, the magnetization-free layer, the first non-magnetic layer, and the first magnetization-fixed layer. The magnetic sensor according to any one of configurations 1 to 3, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer. [Composition 7] The at least one magnetic field sensing element has an antiferromagnetic layer, and the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, and the antiferromagnetic layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The magnetic sensor according to any one of configurations 1 to 4, wherein the magnetization direction of the first magnetization-fixing layer is fixed by exchange coupling with the antiferromagnetic layer. [Structure 8] The at least one magnetic field sensing element comprises an intermediate layer made of a non-magnetic metal, a second magnetization-fixed layer, and an antiferromagnetic layer, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the intermediate layer, the second magnetization-fixed layer, and the antiferromagnetic layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, the intermediate layer, the second magnetization-fixed layer, and the antiferromagnetic layer. The magnetic sensor according to any one of configurations 1 to 4, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer by exchange coupling with the antiferromagnetic layer. [Composition 9] The magnetic sensor according to any one of configurations 1 to 8, wherein the magnetization direction of the magnetized free layer is oriented perpendicular to the first direction in the absence of the external magnetic field. [Configuration 10] The magnetic sensor according to any one of configurations 1 to 8, wherein the magnetization direction of the magnetized free layer forms a vortex shape in a plane perpendicular to the first direction in the absence of the external magnetic field. [Composition 11] The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The magnetization direction of the magnetized free layer of each magnetic field sensing element forms a vortex shape in a plane perpendicular to the first direction when there is no external magnetic field. The plurality of magnetic field sensing elements are connected in series and face one of the first soft magnetic layers in the first direction. The magnetic sensor according to configuration 10, wherein some and the remainder of the plurality of magnetic field sensing elements are located on both sides of a plane containing a center line parallel to the first direction of the first soft magnetic layer, and the magnetization directions at the center of the vortex shape are opposite to each other. [Composition 12] The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The system has first and second element units, each containing a portion of the aforementioned plurality of magnetic field sensing elements, The first element unit and the second element unit form a set connected in series, with one end of the set connected to a power supply and the other end grounded. It has an output section located between the first element unit and the second element unit, The magnetic sensor according to any one of configurations 1 to 11, wherein the magnetization direction of the first magnetization fixed layer of the first element unit and the magnetization direction of the first magnetization fixed layer of the second element unit are opposite to each other. [Composition 13] The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The system has first to fourth element units, each containing a portion of the aforementioned plurality of magnetic field sensing elements, The first element unit and the second element unit are connected in series to form a first pair, the third element unit and the fourth element unit are connected in series to form a second pair, one end of the first pair and the second pair are connected to a power supply and the other end is grounded. The first element unit and the fourth element unit are arranged on the power supply side, and the second element unit and the third element unit are arranged on the ground side. The device includes a differencer that calculates the difference between the output between the first element unit and the second element unit and the output between the third element unit and the fourth element unit. A magnetic sensor according to any one of configurations 1 to 11, wherein the magnetization directions of the first magnetization fixed layers of the first element unit and the third element unit are in the same direction, and the magnetization directions of the first magnetization fixed layers of the second element unit and the fourth element unit are in the opposite direction to the magnetization directions of the first magnetization fixed layers of the first element unit and the third element unit. [Composition 14] The magnetic sensor according to configuration 13, wherein the at least one first soft magnetic layer is a single first soft magnetic layer, and the single first soft magnetic layer faces the first to fourth element units. [Manufacturing method 1] The first element unit and the second element unit are configured as a set in which the first element unit and the second element unit are connected in series, one end of the set is connected to a power supply and the other end is grounded, an output unit is provided between the first element unit and the second element unit, and at least one magnetic field sensing element is provided in each of the first element unit and the second element unit. Providing at least one magnetic field detection element in the first element unit and the second element unit means that The first magnetization-fixed layer, the magnetization-free layer whose magnetization direction changes with respect to an external magnetic field, the first non-magnetic layer, and the antiferromagnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The first element unit is locally heated while a magnetic field is applied in the first direction to magnetize the first magnetization fixed layer of the first element unit, The first magnetization fixing layer of the second element unit is magnetized by applying a magnetic field in a second direction opposite to the first direction while locally heating the second element unit, A method for manufacturing a magnetic sensor having [Manufacturing method 2] The manufacturing method according to manufacturing method 1, wherein the first element unit and the second element unit are locally heated by irradiating them with laser light. [Manufacturing method 3] The first to fourth element units are constructed such that the first and second element units are connected in series to form a first set, the third and fourth element units are connected in series to form a second set, one end of the first and second sets is connected to a power supply and the other end is grounded, the first and fourth element units are positioned on the power supply side, the second and third element units are positioned on the ground side, and each of the first to fourth element units is provided with at least one magnetic field sensing element. The method includes creating a differencer that calculates the difference between the output between the first element unit and the second element unit and the output between the third element unit and the fourth element unit, Providing at least one magnetic field sensing element in the first to fourth element units means that The first magnetization-fixed layer, the magnetization-free layer whose magnetization direction changes with respect to an external magnetic field, the first non-magnetic layer, and the antiferromagnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The first element unit and the third element unit are locally heated while a magnetic field is applied in the first direction to magnetize the first magnetization fixed layer of the first element unit and the third element unit, The second element unit and the fourth element unit are locally heated while a magnetic field is applied in a second direction opposite to the first direction to magnetize the first magnetization fixed layer of the second element unit and the fourth element unit. A method for manufacturing a magnetic sensor having [Manufacturing method 4] The manufacturing method according to manufacturing method 3, wherein the first to fourth element units are locally heated by irradiating them with laser light. [Explanation of Symbols]

[0045] 1. Magnetic sensor 2 Magnetic field detection element 3. First soft magnetic layer 4. Second soft magnetic layer 5 Upper electrode layer 5 6 Laminate 7 Lower electrode layer 11-14 Element Units 1-4 61 Magnetization free layer 62 First non-magnetic layer 63 First magnetization fixed layer 64 Middle Class 65 Second magnetization fixed layer 66 Second non-magnetic layer 67 Antiferromagnetic layer

Claims

1. It comprises at least one magnetic field sensing element and at least one first soft magnetic layer, The at least one magnetic field sensing element comprises a first magnetization fixed layer, a magnetization free layer whose magnetization direction changes with respect to an external magnetic field, and a first non-magnetic layer. A magnetic sensor in which the first magnetization-fixed layer, the magnetization-free layer, and the first non-magnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, and the first magnetization-fixed layer, the magnetization direction of the first magnetization-fixed layer is fixed in the first direction, and the at least one first soft magnetic layer faces the at least one magnetic field sensing element in the first direction.

2. The magnetic sensor according to claim 1, having at least one second soft magnetic layer facing the at least one magnetic field sensing element in the first direction, wherein the at least one magnetic field sensing element is located between the at least one first soft magnetic layer and the at least one second soft magnetic layer.

3. The magnetic sensor according to claim 2, wherein the magnetization free layer has a long axis, at least one of the first soft magnetic layer and the second soft magnetic layer has a long axis, and the long axis of the magnetization free layer and the long axis of at least one of the first soft magnetic layer and the second soft magnetic layer are parallel.

4. The magnetic sensor according to claim 1, wherein the first non-magnetic layer is an insulating layer.

5. The at least one magnetic field sensing element comprises a second magnetization-fixed layer and an intermediate layer made of a non-magnetic metal, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the second magnetization-fixed layer, and the intermediate layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, the intermediate layer, and the second magnetization-fixed layer. The magnetic sensor according to claim 1, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer.

6. The at least one magnetic field sensing element comprises a second magnetization-fixed layer and a second non-magnetic layer, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the second magnetization-fixed layer, and the second non-magnetic layer are arranged in the first direction in the order of the second magnetization-fixed layer, the second non-magnetic layer, the magnetization-free layer, the first non-magnetic layer, and the first magnetization-fixed layer. The magnetic sensor according to claim 1, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer.

7. The at least one magnetic field sensing element has an antiferromagnetic layer, and the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, and the antiferromagnetic layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The magnetic sensor according to claim 1, wherein the magnetization direction of the first magnetization-fixing layer is fixed by exchange coupling with the antiferromagnetic layer.

8. The at least one magnetic field sensing element comprises an intermediate layer made of a non-magnetic metal, a second magnetization-fixed layer, and an antiferromagnetic layer, wherein the first magnetization-fixed layer, the magnetization-free layer, the first non-magnetic layer, the intermediate layer, the second magnetization-fixed layer, and the antiferromagnetic layer are arranged in the first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, the intermediate layer, the second magnetization-fixed layer, and the antiferromagnetic layer. The magnetic sensor according to claim 1, wherein the magnetization direction of the second magnetization fixed layer is fixed in the opposite direction to the magnetization direction of the first magnetization fixed layer by exchange coupling with the antiferromagnetic layer.

9. The magnetic sensor according to claim 1, wherein the magnetization direction of the magnetized free layer is oriented perpendicular to the first direction in the absence of the external magnetic field.

10. The magnetic sensor according to claim 1, wherein the magnetization direction of the magnetized free layer forms a vortex shape in a plane perpendicular to the first direction in the absence of the external magnetic field.

11. The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The magnetization direction of the magnetized free layer of each magnetic field sensing element forms a vortex shape in a plane perpendicular to the first direction when there is no external magnetic field. The plurality of magnetic field sensing elements are connected in series and face one of the first soft magnetic layers in the first direction. The magnetic sensor according to claim 10, wherein some and the remainder of the plurality of magnetic field sensing elements are located on both sides of a plane containing a center line parallel to the first direction of the first soft magnetic layer, and the magnetization directions at the center of the vortex shape are opposite to each other.

12. The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The system has first and second element units, each containing a portion of the plurality of magnetic field detection elements, The first element unit and the second element unit form a set connected in series, with one end of the set connected to a power supply and the other end to ground. It has an output section located between the first element unit and the second element unit, The magnetic sensor according to any one of claims 1 to 11, wherein the magnetization direction of the first magnetization fixed layer of the first element unit and the magnetization direction of the first magnetization fixed layer of the second element unit are opposite to each other.

13. The aforementioned at least one magnetic field sensing element is a plurality of magnetic field sensing elements, The system has first to fourth element units, each containing a portion of the aforementioned plurality of magnetic field sensing elements, The first element unit and the second element unit are connected in series to form a first set, the third element unit and the fourth element unit are connected in series to form a second set, one end of the first set and the second set are connected to a power supply and the other end is grounded. The first element unit and the fourth element unit are arranged on the power supply side, and the second element unit and the third element unit are arranged on the ground side. The system includes a differencer that calculates the difference between the output between the first element unit and the second element unit and the output between the third element unit and the fourth element unit. The magnetic sensor according to any one of claims 1 to 11, wherein the magnetization directions of the first magnetization fixed layer of the first element unit and the third element unit are in the same direction, and the magnetization directions of the first magnetization fixed layer of the second element unit and the fourth element unit are in the opposite direction to the magnetization directions of the first magnetization fixed layer of the first element unit and the third element unit.

14. The magnetic sensor according to claim 12, wherein the at least one first soft magnetic layer is a single first soft magnetic layer, and the single first soft magnetic layer faces the first to fourth element units.

15. The first element unit and the second element unit are configured as a set in which the first element unit and the second element unit are connected in series, one end of the set is connected to a power supply and the other end is grounded, an output unit is provided between the first element unit and the second element unit, and at least one magnetic field sensing element is provided in each of the first element unit and the second element unit. Providing at least one magnetic field detection element in the first element unit and the second element unit means that The first magnetization-fixed layer, the magnetization-free layer whose magnetization direction changes with respect to an external magnetic field, the first non-magnetic layer, and the antiferromagnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The first element unit is locally heated while a magnetic field is applied in the first direction to magnetize the first magnetization fixed layer of the first element unit, The first magnetization fixing layer of the second element unit is magnetized by applying a magnetic field in a second direction opposite to the first direction while locally heating the second element unit, A method for manufacturing a magnetic sensor having

16. The manufacturing method according to claim 15, wherein the first element unit and the second element unit are locally heated by irradiating them with laser light.

17. The first to fourth element units are constructed such that the first and second element units are connected in series to form a first set, the third and fourth element units are connected in series to form a second set, one end of the first and second sets is connected to a power supply and the other end is grounded, the first and fourth element units are positioned on the power supply side, the second and third element units are positioned on the ground side, and each of the first to fourth element units is provided with at least one magnetic field sensing element. The invention includes creating a differencer that calculates the difference between the output between the first element unit and the second element unit and the output between the third element unit and the fourth element unit, Providing at least one magnetic field detection element in the first to fourth element units means that The first magnetization-fixed layer, the magnetization-free layer whose magnetization direction changes with respect to an external magnetic field, the first non-magnetic layer, and the antiferromagnetic layer are arranged in a first direction in the order of the magnetization-free layer, the first non-magnetic layer, the first magnetization-fixed layer, and the antiferromagnetic layer. The first element unit and the third element unit are locally heated while a magnetic field is applied in the first direction to magnetize the first magnetization fixed layer of the first element unit and the third element unit, The second element unit and the fourth element unit are locally heated while a magnetic field is applied in a second direction opposite to the first direction to magnetize the first magnetization fixed layer of the second element unit and the fourth element unit. A method for manufacturing a magnetic sensor having

18. The manufacturing method according to claim 17, wherein the first to fourth element units are locally heated by irradiating them with laser light.

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