Method for manufacturing magnetic sensor

Abstract

A method for manufacturing a magnetic sensor according to the present invention is a method for manufacturing a magnetic sensor 1 in which a first magnetoresistive effect element (for example, a magnetoresistive effect element 10a) having a first fixed layer (for example, a fixed layer 11 of the magnetoresistive effect element 10a) in which the magnetization thereof is fixed in a first direction is provided on a substrate, and a first spin hole part (spin hole part 20) corresponding to the first fixed layer is provided on the substrate, the method comprising forming the first fixed layer, performing a first annealing for heating the first spin hole part while energizing the first spin hole part to generate a spin orbit torque in the first spin hole part (spin hole part 20), and fixing the magnetization of the first fixed layer in the first direction on the basis of the generated spin orbit torque. Therefore, it is possible to fix the magnetization of the first fixed layer of the magnetoresistive effect element by a method different from a magnetization treatment.

Description

Method for manufacturing magnetic sensor

[0001] The present invention relates to a method for manufacturing a magnetic sensor having a magnetoresistive effect element.

[0002] Examples of magnetic sensors for detecting and measuring magnetic fields include magnetic detection elements provided with magnetoresistive effect elements using the GMR (Giant Magnetoresistive) effect or TMR (Tunnel Magnetoresistive) effect, and magnetic detection elements composed of Hall elements.

[0003] A magnetoresistive effect element has a structure in which a free magnetic layer whose magnetization direction can be changed to follow the direction of a measurement magnetic field, and a fixed layer whose magnetization direction does not change even when receiving the measurement magnetic field, are laminated with a non-magnetic layer interposed therebetween. As a method for fixing the magnetization of the fixed layer (in this specification, setting the magnetization of the fixed layer to such an extent that it does not change even when receiving a measurement magnetic field is referred to as "fixing"), for example, film formation in a magnetic field disclosed in Patent Document 1 (particularly Claim 2), and annealing in a magnetic field disclosed in Patent Document 2 (particularly Claim 9) can be cited.

[0004] International Publication No. 2017-094889, Japanese Patent Laid-Open No. 2020-191325

[0005] An object of the present invention is to provide a method for manufacturing a magnetic sensor, including a method of fixing the magnetization of the fixed layer of a magnetoresistive effect element based on a principle different from that of the prior art.

[0006] In one aspect, the present invention is a method for manufacturing a magnetic sensor, wherein a substrate is provided with a first magnetoresistive effect element having a first fixed layer whose magnetization is fixed in a first direction, and a first spin hall portion corresponding to the first fixed layer is provided on the substrate, the method comprising: forming the first fixed layer, performing a first annealing of heating the first spin hall portion while energizing the first spin hall portion to generate spin-orbit torque in the first spin hall portion, and fixing the magnetization of the first fixed layer in the first direction based on the generated spin-orbit torque. In the above manufacturing method, the substrate may be provided with a second magnetoresistive effect element having a second fixed layer whose magnetization is fixed in a second direction different from the first direction.

[0007] Magnetic field deposition and magnetic field annealing involve performing the deposition process or heat treatment while applying an external magnetic field (hereinafter, magnetic field deposition and magnetic field annealing are collectively referred to as magnetic field application treatment). Therefore, the magnetization direction of the fixed layer being treated is limited to the direction along the applied external magnetic field. Consequently, if there are multiple fixed layers to be treated and each of them needs to be magnetized in a different direction, the magnetic field application treatment must be performed multiple times. When the magnetic field application treatment is performed multiple times, there is a concern that the magnetization fixed in the first magnetic field application treatment will be affected by the external magnetic field applied in subsequent magnetic field application treatments, resulting in increased dispersion, that is, an increase in the component magnetized in a direction different from the fixed magnetization direction.

[0008] As with the magnetic sensor described above, when using spin-orbit torque, the spin diffusion length of the spin current that generates the spin-orbit torque is generally submicron or less. Therefore, a strong magnetic field can be applied only to components placed in very close proximity, such as those in contact with the spin Hall region where the spin current is generated. Consequently, even when there are multiple stationary layers to be magnetized in different directions on the same substrate, fixing the magnetization of one stationary layer using spin-orbit torque can significantly reduce the magnetic influence on other stationary layers. Therefore, even in a configuration where multiple magnetoresistive elements are densely arranged on the same substrate, i.e., a high-density mounting configuration, the problem of large dispersion of the stationary layers of each magnetoresistive element is less likely to occur, and a magnetic sensor with high measurement accuracy can be obtained.

[0009] In the above manufacturing method, a second spin hole portion corresponding to the second fixed layer is provided in the substrate, and in the first annealing, current is also passed to the second spin hole portion to generate a spin-orbit torque in the second spin hole portion, and based on the generated spin-orbit torque, the magnetic anisotropy of the second fixed layer is aligned to the second direction, and the magnetization of the first fixed layer is fixed to the first direction by the first annealing, and the magnetization of the second fixed layer is fixed to the second direction. In this way, when multiple spin hole portions are provided corresponding to multiple fixed layers, it is possible to magnetize each of the multiple fixed layers in any direction without being affected by (or affecting) the other fixed layers.

[0010] In the above manufacturing method, the magnetization of the first stationary layer may be fixed in the first direction and the magnetization of the second stationary layer may be fixed in the second direction by performing the first annealing while applying a magnetic field in the second direction. That is, if some of the multiple stationary layers are not provided with spin Hall portions that are magnetically coupled to the stationary layer, the magnetization of the stationary layers without spin Hall portions can be fixed by performing a magnetic field application process that involves applying an external magnetic field in the direction in which the magnetization of the stationary layers without spin Hall portions should be fixed. For stationary layers provided with spin Hall portions, the influence of the external magnetic field applied by the magnetic field application process (increase in magnetization dispersion) can be sufficiently reduced by appropriately increasing the spin orbit torque from the spin Hall portions.

[0011] In the above manufacturing method, the magnetic sensor may include a half-bridge circuit having the first magnetoresistive element and the second magnetoresistive element, or it may include a full-bridge circuit having two of the first magnetoresistive elements and two of the second magnetoresistive elements.

[0012] In another embodiment, the present invention provides a method for manufacturing a magnetic sensor comprising a first magnetoresistive element having a first fixed layer whose magnetization is fixed in a first orientation, and a plurality of magnetoresistive elements having at least one fixed layer whose magnetization is fixed in an orientation different from the first orientation, all on the same substrate, wherein a first spin hole portion corresponding to the first fixed layer is provided on the substrate. In this manufacturing method, a spin-orbit torque is generated in the first spin hole portion by performing a first annealing by heating while energizing the first spin hole portion, and the magnetization of the first fixed layer is fixed in a first orientation based on the generated spin-orbit torque.

[0013] In the above manufacturing method, for a co-oriented fixed layer among the fixed layers of the plurality of magnetoresistive elements, in which the magnetization is fixed in the first direction, the first spin hole portion corresponding to the co-oriented fixed layer is provided on the substrate, and in the first annealing, the magnetic anisotropy of the first fixed layer and the co-oriented fixed layer is fixed in the first direction by energizing all of the first spin hole portions.

[0014] In the above manufacturing method, there are three or more magnetoresistive elements provided on the substrate, and for a non-cooriented fixed layer among the fixed layers of the plurality of magnetoresistive elements, in which the magnetization is fixed in a predetermined direction different from the first direction, a non-cooriented spin hole portion corresponding to the non-cooriented fixed layer is provided on the substrate, and in the first annealing, current is also passed to the non-cooriented spin hole portion to fix the magnetization of the first fixed layer and the cooriented fixed layer in the first direction, and the magnetization of the non-cooriented fixed layer in the predetermined direction.

[0015] In the above manufacturing method, the side of the first spin hole portion facing the first stationary layer may have a portion made of an antiferromagnetic material, and the first stationary layer and the first spin hole portion may be magnetically coupled. In this case, an exchange coupling interaction may occur between the first stationary layer and the first spin hole portion in the state before the start of the first annealing.

[0016] In the above manufacturing method, a magnetic layer may be further provided between the first fixed layer and the first spin hole portion.

[0017] According to the present invention, it is possible to fix the magnetization of the stationary layer of a magnetoresistive element using a method different from that of magnetization application treatment.

[0018] This is a block diagram of a magnetic sensor according to one embodiment of the present invention. This is an explanatory diagram of a full-bridge circuit having a first example of a magnetic field detection unit in a magnetic sensor according to one embodiment of the present invention. This is an XZ cross-sectional view along line A-A' in Figure 2. This is an XZ cross-sectional view along line B-B' in Figure 2. This is a diagram illustrating the manufacturing method (before the first annealing) of a first example of an individual magnetic field detection unit in a magnetic sensor according to the first embodiment of the present invention. This is a diagram illustrating the manufacturing method (during the first annealing) of a first example of an individual magnetic field detection unit in a magnetic sensor according to the first embodiment of the present invention. This is an explanatory diagram of a second example of a magnetic field detection unit in a magnetic sensor according to the first embodiment of the present invention, and is an XZ cross-sectional view along the cutting line corresponding to line A-A' in Figure 2. This is a diagram illustrating the manufacturing method (before the first annealing) of a second example of an individual magnetic field detection unit in a magnetic sensor according to the first embodiment of the present invention. This is a diagram illustrating the manufacturing method (during the first annealing) of a second example of an individual magnetic field detection unit in a magnetic sensor according to the first embodiment of the present invention. This is an explanatory diagram of a first modified example of a first example of a magnetic field detection unit in a magnetic sensor according to one embodiment of the present invention, and is an XZ cross-sectional view along the cutting line corresponding to line A-A' in Figure 2. This is an explanatory diagram of a second modified example of a first example of a magnetic field detection unit included in a magnetic sensor according to one embodiment of the present invention, and is a cross-sectional view of XZ along the cutting line corresponding to line A-A' in Figure 2.

[0019] Embodiments of the present invention will be described below with reference to the accompanying drawings. In each drawing, the same component is given the same number, and its description is omitted. Reference coordinates are shown in each drawing as appropriate to indicate the positional relationship of each component. The reference coordinates are defined by three mutually orthogonal directions (X direction, Y direction, and Z direction), and the orientation of each direction is expressed as X1 direction (or X1 direction). In this specification, the direction in which the measurement magnetic field H is applied is also referred to as the "first direction".

[0020] (First Embodiment) Figure 1 is a block diagram of a magnetic sensor according to one embodiment of the present invention. Figure 2 is an explanatory diagram of a full-bridge circuit included in the magnetic sensor according to one embodiment of the present invention. The magnetic sensor 1 of this embodiment includes a magnetic field detection unit 2, a power supply unit 3, a magnetic field calculation unit 4 and an amplifier 5, an analog-to-digital conversion circuit (A / D conversion circuit 6) and a control unit 7. The control unit 7 controls each part that constitutes the magnetic sensor 1 and is configured as a CPU (central processing unit) and a program, etc.

[0021] The magnetic field detection unit 2 detects the external magnetic field to be measured (measured magnetic field H), and as shown in Figure 2, it has four individual magnetic field detection units 100a, 100b, 100c, and 100d. Individual magnetic field detection unit 100a has a magnetoresistive element 10a, individual magnetic field detection unit 100b has a magnetoresistive element 10b, individual magnetic field detection unit 100c has a magnetoresistive element 10c, and individual magnetic field detection unit 100d has a magnetoresistive element 10d. The magnetoresistive elements 10a, 10b, 10c, and 10d constitute a full-bridge circuit 15, forming the magnetic field detection unit 2 that measures the magnetic field along the X direction. The power supply unit 3 applies a predetermined current or voltage to each unit based on a control signal from the control unit 7. The power supply unit 3 may also have a function to measure the signal from the magnetic field detection unit 2.

[0022] The magnetic field calculation unit 4 calculates the measured magnetic field H based on the output of the magnetic field detection unit 2. In the magnetic sensor 1, after the magnetic field calculation unit 4 calculates the measured magnetic field H, the signal corresponding to the calculated measured magnetic field H is amplified by the amplifier 5 and then converted into digital data by the A / D conversion circuit 6.

[0023] The four magnetoresistive elements 10a, 10b, 10c, and 10d in the magnetic field detection unit 2 of the magnetic sensor 1 according to one embodiment of the present invention may be provided on the same substrate (one chip). In this embodiment, the four magnetoresistive elements 10a, 10b, 10c, and 10d are provided on the same substrate (not shown) in Figure 2, and Figure 2 is a view of the magnetic field detection unit 2 of the magnetic sensor 1 as seen from the laminated surface (front surface) of the substrate in the direction normal to the substrate. That is, in Figure 2, the Z1 side is the front surface of the substrate, and the Z2 side is the back surface of the substrate. The Z direction is along the lamination direction of the magnetoresistive elements 10a, 10b, 10c, and 10d.

[0024] The magnetic field detection unit 2 has a full bridge circuit 15 in which a first half-bridge circuit, in which magnetoresistive elements 10a and 10b, both extending in the Y direction, are connected in series between the power supply terminal Vdd, which is the power supply point from the power supply unit 3, and the ground terminal GND, and a second half-bridge circuit, in which magnetoresistive elements 10c and 10d, both extending in the Y direction, are connected in series, are connected in parallel.

[0025] The first half-bridge circuit has an output terminal V1 between magnetoresistive elements 10a and 10b. The second half-bridge circuit has an output terminal V2 between magnetoresistive elements 10c and 10d. The potential difference between these two output terminals V1 and V2 (midpoint potential Va of the first half-bridge circuit - midpoint potential Vb of the second half-bridge circuit) allows for the quantitative measurement of the magnitude of an externally applied magnetic field as the measured magnetic field H. In this embodiment, a first signal including the midpoint potential Va from output terminal V1 and a second signal including the midpoint potential Vb from output terminal V2 are output from the magnetic field detection unit 2, and the processing performed by the magnetic field calculation unit 4 includes calculating the midpoint potential difference using these first and second signals as input.

[0026] The fixed layer 11 (see Figure 3) of the pair of magnetoresistive elements 10a and 10b forming the first half-bridge circuit can maintain its magnetization 11m in a predetermined direction even when subjected to a measurement magnetic field H within the measurement range. Specifically, the magnetization 11m of the fixed layer 11 is oriented X2 with respect to magnetoresistive element 10a and X1 with respect to magnetoresistive element 10b, along the X direction, which is the direction in which the measurement magnetic field H is applied (first direction), as shown by the white arrows in Figure 2. Similarly, in the pair of magnetoresistive elements 10c and 10d forming the second half-bridge circuit, the magnetization 11m of the fixed layer 11 is oriented X1 with respect to magnetoresistive element 10c and X2 with respect to magnetoresistive element 10d, as shown by the white arrows in Figure 2. Note that in Figure 2, the measurement magnetic field H has not yet been applied, so the measurement magnetic field H is shown by a dashed arrow along the X direction. The same applies to other drawings such as Figure 3A.

[0027] In the first half-bridge circuit and the second half-bridge circuit, the magnetization 11m of the fixed layer 11 of the magnetoresistive element 10b on the power terminal Vdd side and the magnetization 11m of the fixed layer 11 of the magnetoresistive element 10d are in opposite directions (antiparallel). Also, the magnetization 11m of the fixed layer 11 of the magnetoresistive element 10a on the ground terminal GND side and the magnetization 11m of the fixed layer 11 of the magnetoresistive element 10c are in opposite directions (antiparallel). Therefore, the sensitivity axis direction of the magnetoresistive elements 10a, 10b, 10c, and 10d is all in the X direction (first direction).

[0028] Furthermore, in the four magnetoresistive elements 10a, 10b, 10c, and 10d, the direction of magnetization 13m of the free magnetic layer 13 (see Figure 3A, etc.) when no measurement magnetic field H is applied is the same and aligns with the Y2 direction, as indicated by the black arrow in Figure 2. When the free magnetic layer 13 receives a measurement magnetic field H in the first direction (X direction), it can be magnetized in a direction aligned with the measurement magnetic field H.

[0029] In magnetoresistive elements 10a, 10b, 10c, and 10d according to one aspect of the present invention, the direction of the magnetization 13m of the free magnetic layer 13 in a no-magnetic-field state where no measurement magnetic field H is applied is aligned with the direction of Y2, which is perpendicular to the direction of the magnetization 11m of the fixed layer 11, by a bias magnetic field. As a result, the magnetoresistive elements 10a, 10b, 10c, and 10d exhibit reduced hysteresis in the measurement of the measurement magnetic field H. In order for the magnetization 13m of the free magnetic layer 13 to rotate in the first direction when the measurement magnetic field H is applied, the strength of the measurement magnetic field H must be high enough to exceed the strength of the bias magnetic field applied to align the magnetization 13m of the free magnetic layer 13 with the Y2 direction.

[0030] With the above configuration, as the magnitude of the measured magnetic field H in the X direction changes, the outputs from the output terminal V1 of the first half-bridge circuit and the output terminal V2 of the second half-bridge circuit change in opposite directions. Therefore, a large output is obtained as the potential difference (Va - Vb) between the two output terminals V1 and V2. Thus, the magnetic sensor 1 can detect the measured magnetic field H with high precision. In addition, the first half-bridge circuit or the second half-bridge circuit can be used instead of the full-bridge circuit 15, or the magnetoresistive element 10a can be used alone.

[0031] (First example) Figure 3A is an XZ cross-sectional view taken along the line A-A' in Figure 2. Figure 3B is an XZ cross-sectional view taken along the line B-B' in Figure 2. Some components, such as the substrate on which the magnetoresistive element 10a is provided, and the portion made of insulating material provided between adjacent magnetoresistive elements (magnetoresistive element 10a and magnetoresistive element 10c in Figure 3A), are not shown.

[0032] As shown in Figures 3A and 3B, the individual magnetic field detection units 100a, 100b, 100c, and 100d each comprise magnetoresistive elements 10a, 10b, 10c, and 10d, which are film-like bodies formed on a substrate, and a spin Hall portion 20, and these have a stacked structure in the Z direction. The magnetoresistive elements 10a, 10b, 10c, and 10d have a free magnetic layer 13 which is a magnetosensitive portion that can be magnetized in the first direction (X direction) along the measured magnetic field H, a fixed layer 11 which can maintain a state in which the magnetization 11m is aligned with the first direction (X direction) in Figure 3, and a non-magnetic layer 12 located between the free magnetic layer 13 and the fixed layer 11, and exhibit a magnetoresistive effect.

[0033] The magnetoresistive elements 10a, 10b, 10c, and 10d change the direction of magnetization between the free magnetic layer 13, which sandwiches the non-magnetic layer 12, and the fixed layer 11 due to the measurement magnetic field H. This changes the resistance values ​​of the magnetoresistive elements 10a, 10b, 10c, and 10d, and by detecting this change in resistance, the strength of the measurement magnetic field H applied to the free magnetic layer 13, which is the magnetosensitive part, can be measured. In the following detailed explanation, the individual magnetic field detection unit 100a may be used as a specific example, but the individual magnetic field detection units 100b, 100c, and 100d have a similar configuration.

[0034] The fixed layer 11 is made of a magnetic material such as a CoFe alloy (cobalt-iron alloy). The non-magnetic layer 12 is an insulating barrier layer made of, for example, MgO, Al2O3, or titanium oxide, when the magnetoresistive element 10a is a tunnel magnetoresistive element (TMR). The free magnetic layer 13 is made of a soft magnetic material such as a CoFe alloy or NiFe alloy (nickel-iron alloy). The fixed layer 11 and the free magnetic layer 13 may be single-layer or multilayer structures. In the case of a multilayer structure, it is sometimes preferable to have a multilayer ferri structure. When the magnetoresistive element 10a is a giant magnetoresistive element (GMR), a non-magnetic material such as Cu is used as the constituent material of the non-magnetic layer 12. In this embodiment, the free magnetic layer 13 is located on the Z1 side of the magnetoresistive element 10a, and the detection center 10P of the magnetoresistive element 10a is located at the center of the free magnetic layer 13.

[0035] In this embodiment, the magnetoresistive element 10a of the individual magnetic field detection unit 100a is, as one specific example, a tunnel magnetoresistive element (TMR). For the purpose of measuring the electrical characteristics of the magnetoresistive element 10a, measurement wiring 62 is provided so that a voltage from a measurement power supply is applied in a third direction (Z direction) between the free magnetic layer 13 and the fixed layer 11 of the magnetoresistive element 10a. In this embodiment, the magnetoresistive element 10a and the spin hole portion 20 are stacked in the third direction (Z direction). Since the spin hole portion 20 is made of a conductive material, the measurement wiring 62 is provided so that a voltage from a measurement power supply is applied to the free magnetic layer 13 via the spin hole portion 20. Note that Figure 3A corresponds to the cross-section of line A-A' in Figure 2, and therefore in Figure 3A, the measurement wiring 62 is depicted as wiring connecting the Z1 side end of the magnetoresistive element 10a to the ground terminal GND, and wiring connecting the Z2 side end of the spin hole portion 20 to the output terminal V1.

[0036] The spin Hall portion 20 of the individual magnetic field detection unit 100a generates a spin current 20sa in the thickness direction (Z direction) when current is passed in the in-plane direction (XY in-plane direction), specifically when a current 20ca is applied from the control power supply Ia along the X direction. The polarization direction (spin direction) of the spins generated by the current is oriented in the Y direction, which is perpendicular to the direction of current (X direction) in the plane. That is, the direction of current (X direction), the direction of the spin current 20sa (Z direction), and the direction of the spin flowing along the spin current 20sa (Y direction) are all orthogonal to each other. Based on the spin-orbit torque of the spin current 20sa generated in the spin Hall portion 20, the magnetic anisotropy of the fixed layer 11 of the magnetoresistive element 10a is set to the X2 direction, and this magnetic anisotropy does not change even when subjected to the measured magnetic field H. That is, the magnetization 11m of the fixed layer 11 is fixed by the spin-orbit torque from the spin Hall portion 20. In Figure 3A, in the individual magnetic field detection unit 100c located on the X1 side of the individual magnetic field detection unit 100a, a spin current 20sc in the thickness direction (Z direction) is generated by applying a current 20cc along the X direction from the control power supply Ic to the spin Hall portion 20 provided in the individual magnetic field detection unit 100c. Based on the spin orbit torque of the generated spin current 20sc, the magnetic anisotropy of the fixed layer 11 of the magnetoresistive element 10c is fixed in the direction of X1.

[0037] In the individual magnetic field detection unit 100b shown in Figure 3B, a current 20cb along the X direction is applied from the control power supply Ib to the spin Hall portion 20 of the individual magnetic field detection unit 100b, generating a spin current 20sb in the thickness direction (Z direction). Based on the spin orbit torque of the generated spin current 20sb, the magnetic anisotropy of the fixed layer 11 of the magnetoresistive element 10b is fixed in the X1 direction. In addition, in the individual magnetic field detection unit 100d located on the X1 side of the individual magnetic field detection unit 100b, a spin current 20sd in the thickness direction (Z direction) is generated by applying a current 20cd along the X direction from the control power supply Id to the spin Hall portion 20 of the individual magnetic field detection unit 100d. Based on the spin orbit torque of the generated spin current 20sd, the magnetic anisotropy of the fixed layer 11 of the magnetoresistive element 10d is fixed in the X2 direction.

[0038] The length (spin diffusion length) over which the spin currents 20sa, sb, sc, and sd generated in the spin hole portion 20 can be aligned in a predetermined direction depends on the constituent material of the spin hole portion 20, but is generally submicron or less. When the spin hole portion 20 is a film-like material, as in this embodiment, the direction of current 20ca applied to the spin hole portion 20 is set in the XY plane direction so that the Z direction, which is the thickness direction, is the direction of the spin currents 20sa, sb, sc, and sd. Specifically, as shown in Figures 3A and 3B, control wiring 61 is provided so that for all of the individual magnetic field detection units 100a, 100b, 100c, and 100d, the currents 20ca, 20cb, 20cc, and 20cd from the control power supplies Ia, Ib, Ic, and Id are applied to the spin hole portion 20 in the X direction.

[0039] There is a correlation between the directions of the currents 20ca, 20cb, 20cc, and 20cd and the direction of the magnetization 11m of the fixed layer 11. In the individual magnetic field detection units 100a and 100d, where the magnetization 11m is oriented towards X2, the currents 20ca and 20cd are oriented towards X1. On the other hand, in the individual magnetic field detection units 100b and 100c, where the magnetization 11m is oriented towards X1, the currents 20cb and 20cc are oriented towards X2.

[0040] The method for fixing the magnetization 11m of the fixed layer 11 using the spin Hall portion 20 will be explained below with reference to Figures 4 and 5. Figure 4 is a diagram illustrating the manufacturing method (before the first annealing) of a first example of an individual magnetic field detection unit included in a magnetic sensor according to the first embodiment of the present invention. Figure 5 is a diagram illustrating the manufacturing method (during the first annealing) of a first example of an individual magnetic field detection unit included in a magnetic sensor according to the first embodiment of the present invention.

[0041] As shown in Figure 4, a magnetic field 20af in the Z1 direction acts between the spin Hall portion 20 and the stationary layer 11 based on exchange coupling interaction. In this embodiment, as an example without limitation, the spin Hall portion 20 is made of an antiferromagnetic material at least on the Z1 side, thereby creating an exchange coupling interaction between the spin Hall portion 20 and the stationary layer 11. Due to this magnetic field 20af, the stationary layer 11 has magnetic anisotropy in the Z1 direction before the current 20ca is applied from the control power supply Ia. That is, the initial magnetization 11mi of the stationary layer 11 is in the Z1 direction. The method for setting the initial magnetization 11mi of the stationary layer 11 is arbitrary; the spin Hall portion 20 may be formed while applying a magnetic field in the Z1 direction (deposition in a magnetic field), or the spin Hall portion 20 may be formed in a non-magnetic field and then heat-treated while applying a magnetic field in the Z1 direction (annealing in a magnetic field). Alternatively, a magnetic field in the Z1 direction may be applied from the outside.

[0042] With the initial magnetization 11mi of the fixed layer 11 set in this manner, when a current 20ca in the direction of X1 is applied from the control power supply Ia, as shown in Figure 5, the spin current 20sa becomes in the Z direction, and the spin direction becomes in the Y direction. Due to this spin orbit torque, the magnetization 11m of the fixed layer 11 changes from the Z1 direction of the initial magnetization 11mi to the X2 direction. The individual magnetic field detection unit 100d can also change the magnetization 11m of the fixed layer 11 to the X2 direction by a similar process.

[0043] For the individual magnetic field detection units 100b and 100c, the initial magnetization 11mi of the fixed layer 11 is oriented in the Z1 direction similarly to the individual magnetic field detection units 100a and 100d, and the directions of the currents 20cb and 20cc applied from the control power supplies Ib and Ic are set to the X2 direction, which is opposite to the currents 20ca and 20cd, so that the spin directions are opposite to the spin currents 20sb and 20sc, and the magnetization 11m of the fixed layer 11 can be oriented in the X1 direction.

[0044] Here, heat treatment is performed such that the direction of the magnetization 11m of the fixed layer 11 is set to a predetermined direction by the spin-orbit torque from the spin Hall portion 20, and this state is maintained. The heating conditions are set as appropriate, and a non-limiting example is 500°C for 30 minutes. In this example, the first annealing is performed in which current application to the spin Hall portion 20 and the heat treatment are carried out simultaneously. The start timing of current application and the heating start timing of the heat treatment do not need to coincide with each other, but by applying the currents 20ca, 20cb, 20cc, and 20cd from the control power supplies Ia, Ib, Ic, and Id during the period of holding at a predetermined temperature, the magnetization 11m of the fixed layer 11 can be fixed in a predetermined direction.

[0045] That is, the state shown in FIG. 4 is a state before the first annealing is performed, and the state shown in FIG. 5 is a state during the execution of the first annealing. After the first annealing, even if the application of the currents 20ca, 20cb, 20cc, and 20cd from the control power supplies Ia, Ib, Ic, and Id is stopped, the state where the magnetization 11m of the fixed layer is fixed in the predetermined direction is maintained.

[0046] (Second Example) FIG. 6 is an explanatory diagram of a second example of the magnetic field detection unit included in the magnetic sensor according to the first embodiment of the present invention, and is an XZ cross-sectional view taken along a cutting line corresponding to the line AA' in FIG. 2. FIG. 7 is a diagram for explaining the manufacturing method (before the first annealing) of the second example of the individual magnetic field detection unit included in the magnetic sensor according to the first embodiment of the present invention. FIG. 8 is a diagram for explaining the manufacturing method (during the first annealing) of the second example of the individual magnetic field detection unit included in the magnetic sensor according to the first embodiment of the present invention.

[0047] In the manufacturing method according to the second example, the connection method of the control wiring 61 that connects the control power supplies Ia, Ib, Ic, Id and the spin hall portion 20 is different from that of the manufacturing method according to the first example. Specifically, in the manufacturing method according to the second example, the control wiring 61 is provided such that currents 20ca, 20cb, 20cc, 20cd from the control power supplies Ia, Ib, Ic, Id are applied to the spin hall portion 20 in the Y direction.

[0048] Further, the manufacturing method according to the second example is also different in that the direction of the initial magnetization 11mi of the fixed layer 11 in the state before the first annealing shown in FIG. 7 is the X direction. In the individual magnetic field detection unit 100a shown in FIG. 7, the initial magnetization 11mi is oriented in the X2 direction. Although not shown, the initial magnetization 11mi in the individual magnetic field detection unit 100d is also oriented in the X2 direction, while the initial magnetization 11mi in the individual magnetic field detection units 100b and 100c is oriented in the opposite X1 direction.

[0049] In order to realize these orientations of the initial magnetization 11mi, in the manufacturing method according to the second example, the magnetic field 20af based on exchange coupling interaction is set in the X direction. Specifically, the magnetic field 20af is oriented in the X2 direction in the individual magnetic field detection units 100a and 100d, and the magnetic field 20af is oriented in the X1 direction in the individual magnetic field detection units 100b and 100c. Similar to the first example, the Z1 side of the spin hall portion 20 is made of an antiferromagnetic material, and the orientation of the magnetic field 20af can be set by appropriately performing the magnetic field application treatment.

[0050] After appropriately setting the initial magnetization 11mi in this manner, the first annealing is performed. Specifically, as shown in FIG. 8, during the heat treatment, a current 20ca oriented in the Y2 direction is applied from the control power supply Ia, thereby generating a spin current 20sa in the Z direction. The spin direction in this spin current 20sa is the Y direction, and the magnetization 11m of the fixed layer 11 is strengthened in the X2 direction by the spin orbit torque based on this spin, as shown in FIG. The same process is performed in the individual magnetic field detection unit 100d, so that the magnetization 11m of the fixed layer 11 is strengthened in the X2 direction.

[0051] In the individual magnetic field detection units 100b and 100c, a process is performed in the opposite direction to that in the individual magnetic field detection unit 100a. As described above, the initial magnetization 11mi is set in the direction of X1, and by setting the currents 20cb and 20cc from the control power supplies Ib and Ic in the direction of Y1, the magnetization 11m of the fixed layer 11 is strengthened in the direction of X1.

[0052] In the second example, the direction of the magnetization 11m of the fixed layer 11 is the same as the direction of the magnetic field 20af based on the exchange-coupling interaction (direction X2 in Figure 7). Therefore, this magnetic field 20af contributes to fixing the magnetization 11m of the fixed layer 11 even when the magnetic sensor 1 is in use. Consequently, the magnetization 11m of the fixed layer 11 in the second example is expected to be more strongly fixed than the magnetization 11m of the fixed layer 11 in the first example. On the other hand, in the first example, the direction of the magnetic field 20af based on the exchange-coupling interaction for setting the initial magnetization 11mi can be kept constant (direction Z1 in Figure 4), regardless of the direction of the magnetization 11m of the fixed layer 11. Therefore, the first example may simplify the process for setting the initial magnetization 11mi, or it may be possible to increase the spacing between adjacent individual magnetic field detection units, i.e., increase the mounting density.

[0053] (Modifications) Hereinafter, modifications of the manufacturing method according to this embodiment will be described. Figure 9 is an explanatory diagram of a first modification of a first example of a magnetic field detection unit of a magnetic sensor according to one embodiment of the present invention, and is an XZ cross-sectional view taken along the cutting line A-A' in Figure 2. Figure 10 is an explanatory diagram of a second modification of a first example of a magnetic field detection unit of a magnetic sensor according to one embodiment of the present invention, and is an XZ cross-sectional view taken along the cutting line A-A' in Figure 2.

[0054] (First Modification) In the first modification shown in Figure 9, the individual magnetic field detection unit 100c, in which the magnetization 11m of the fixed layer 11 is fixed in the direction of X1, does not have a spin Hall portion 20. Therefore, the first annealing cannot be performed on the individual magnetic field detection unit 100c. Thus, in the manufacturing method according to this example, when performing the first annealing, an external magnetic field Hpx is applied in the second direction, which is the direction of X1. That is, when performing the first annealing on the individual magnetic field detection unit 100a, the individual magnetic field detection unit 100c is subjected to normal magnetic field annealing. At this time, an external magnetic field Hpx in the direction of X1 is also applied to the fixed layer 11 of the individual magnetic field detection unit 100a, which is provided on the same substrate. However, the magnetization 11m of the fixed layer 11 of the individual magnetic field detection unit 100a is set based on the current flow to the spin Hall portion 20, and by making the degree of this setting sufficiently higher than the external magnetic field Hpx, the magnetization 11m of the fixed layer 11 of the individual magnetic field detection unit 100a and the magnetization 11m of the fixed layer 11 of the individual magnetic field detection unit 100c can be fixed simultaneously.

[0055] In the first modified example, as described above, the individual magnetic field detection unit 100c (and similarly the individual magnetic field detection unit 100b) does not have a spin hole section 20. Therefore, the individual magnetic field detection unit 100b and the individual magnetic field detection unit 100c do not need to have a spin hole section 20 or control wiring 61. For this reason, the manufacturing method according to this example is expected to improve productivity and enable high-density mounting.

[0056] (Second Modification) In the second modification shown in Figure 10, a magnetic layer 40 corresponding to at least the fixed layer 11 is provided between the fixed layer 11 and the spin hole portion 20. By providing this magnetic layer 40, the functions that the fixed layer 11 and / or the spin hole portion 20 must have can be reduced, thereby improving design flexibility and productivity.

[0057] Specifically, in the manufacturing methods according to the first and second examples, the side of the spin hole portion 20 facing the stationary layer 11 (Z1 side) is made of an antiferromagnetic material, and an exchange coupling interaction occurs between this antiferromagnetic material and the magnetic material constituting the stationary layer 11, generating a magnetic field 20af, which sets the initial magnetization 11mi. In such a configuration, it is necessary that the side of the spin hole portion 20 facing the stationary layer 11 (Z1 side) is made of an antiferromagnetic material, and the magnetic material constituting the stationary layer 11 that has a portion facing this antiferromagnetic material must be a material suitable for generating a magnetic field 20af based on the exchange coupling interaction.

[0058] Furthermore, the stationary layer 11 is required to be a material suitable for the magnetization 11m to be oriented in a predetermined direction by the spin orbit torque based on the spin current 20sa generated by energizing the spin Hall portion 20. In addition, as it is a magnetoresistive element 10a, the stationary layer 11 is required as a basic characteristic to appropriately interact with the free magnetic layer 13 to produce a magnetoresistive effect (spin valve effect).

[0059] These requirements are relaxed by providing a magnetic layer 40 between the stationary layer 11 and the spin Hall portion 20. Figure 10 shows a specific example in which the individual magnetic field detection unit 100a is in an unenergized state. The exchange coupling interaction occurs between the spin Hall portion 20 and the magnetic layer 40, and the stationary layer 11 is not involved in the generation of the magnetic field 20af based on this interaction. Therefore, the stationary layer 11 only needs to satisfy the requirement of being magnetically coupled with the magnetic layer 40, and the initial magnetization 11mi of the stationary layer 11 can be set in the Z1 direction via the initial magnetization 40mi of the magnetic layer 40 based on the magnetic field 20af.

[0060] Furthermore, Figure 10 shows a specific example of the individual magnetic field detection unit 100c in which the spin Hall portion 20 is energized. The magnetic layer 40 is made of a material that is easily set to have its magnetization 40m oriented towards X1 by the spin orbit torque based on the energization of the spin Hall portion 20. In this case, the stationary layer 11 only needs to satisfy the requirement of being magnetically coupled to the magnetic layer 40, and does not need to directly receive the spin orbit torque from the spin Hall portion 20. Along the magnetization 40m of the magnetic layer 40 that is magnetically coupled to the stationary layer 11, the magnetization 11m of the stationary layer 11 is fixed in the direction of X1.

[0061] Therefore, in the second example shown in Figure 10, the design of the fixed layer 11 can be dedicated to ensuring that the spin valve effect based on interaction with the free magnetic layer 13 is properly generated.

[0062] In Figure 10, the exchange coupling interaction occurs between the spin Hall portion 20 and the magnetic layer 40, but is not limited to this. The exchange coupling interaction may also occur between the magnetic layer 40 and the stationary layer 11. In this case, the spin Hall portion 20 is freed from the need to have a portion made of antiferromagnet. Alternatively, the magnetic layer 40 may have a function to generate a spin current 20sc, similar to the spin Hall portion 20, thereby generating a strong spin-orbit torque. In this case, if the magnetic layer 40 has a function to set the direction of the magnetization 40m by receiving the spin-orbit torque, it is expected that the fixing of the magnetization 11m of the stationary layer 11 will be strengthened.

[0063] The manufacturing method according to the embodiments of the present invention described above can also be described as follows.

[0064] In one embodiment, the present invention provides for the manufacture of a magnetic sensor 1 comprising a first magnetoresistive element (e.g., magnetoresistive element 10a) having a first fixed layer (fixed layer 11) whose magnetization is fixed in a first orientation (e.g., X2 orientation), and a second magnetoresistive element (e.g., magnetoresistive element 10b) having a second fixed layer (fixed layer 11) whose magnetization is fixed in a second orientation (e.g., X1 orientation) different from the first orientation (X2 orientation), both on the same substrate, and a first spin hole portion (e.g., spin hole portion 20 corresponding to magnetoresistive element 10a) corresponding to the first fixed layer (fixed layer 11 of magnetoresistive element 10a) provided on the substrate. A method for manufacturing a magnetic sensor (magnetic sensor 1), characterized by forming a first fixed layer (fixed layer 11 of magnetoresistive element 10a) and a second fixed layer (fixed layer 11 of magnetoresistive element 10b), performing a first annealing by heating while energizing the first spin Hole portion (spin Hole portion 20 of magnetoresistive element 10a) to generate a spin orbit torque in the first spin Hole portion (spin Hole portion 20 of magnetoresistive element 10a), and fixing the magnetization 11m of the first fixed layer (fixed layer 11 of magnetoresistive element 10a) in a first direction (X2 direction) based on the generated spin orbit torque.

[0065] In the above manufacturing method, a second spin hole portion (for example, a spin hole portion 20 corresponding to the magnetoresistive element 10b) corresponding to the second fixed layer (fixed layer 11 of the magnetoresistive element 10b) is provided on the substrate, and in the first annealing, current is also passed to the second spin hole portion (spin hole portion 20 of the magnetoresistive element 10b) to generate a spin orbit torque in the second spin hole portion (spin hole portion 20 of the magnetoresistive element 10b), and based on the generated spin orbit torque, the magnetic anisotropy of the second fixed layer (fixed layer 11 of the magnetoresistive element 10b) is aligned to a second direction (X1 direction), and the magnetization (magnetization 11m) of the first fixed layer (fixed layer 11 of the magnetoresistive element 10a) is fixed to a first direction (X2 direction) by the first annealing, and the magnetization (magnetization 11m) of the second fixed layer (fixed layer 11 of the magnetoresistive element 10b) is fixed to a second direction (X1 direction).

[0066] In the above manufacturing method, by performing the first annealing while applying a magnetic field in a second direction (X1 direction), the magnetization (magnetization 11m) of the first fixed layer (fixed layer 11 of the magnetoresistive element 10a) may be fixed in the first direction (X2 direction), and the magnetization (magnetization 11m) of the second fixed layer (fixed layer 11 of the magnetoresistive element 10b) may be fixed in the second direction (X1 direction).

[0067] In another embodiment, the present invention provides a first magnetoresistive element (e.g., magnetoresistive element 10a) having a first stationary layer (stationary layer 11) whose magnetization is fixed in a first orientation (e.g., X2 orientation), and a plurality of magnetoresistive elements (e.g., magnetoresistive elements 10b to 10d) having at least one stationary layer (stationary layer 11) whose magnetization is fixed in an orientation different from the first orientation (e.g., X1 orientation), all on the same substrate, wherein a first spin hole portion (e.g., an example) corresponding to the first stationary layer (stationary layer 11 of magnetoresistive element 10a) is provided. The present invention relates to a method for manufacturing a magnetic sensor 1 in which a spin hole portion 20 corresponding to a magnetoresistive element 10a is provided on a substrate, characterized in that a spin orbit torque is generated in the first spin hole portion (the spin hole portion 20 of the magnetoresistive element 10a) by performing a first annealing by heating while energizing the first spin hole portion (the spin hole portion 20 of the magnetoresistive element 10a), and the magnetization of the first fixed layer is fixed in a first direction (X2 direction) based on the generated spin orbit torque.

[0068] In the above manufacturing method, among the fixed layers of the plurality of magnetoresistive elements (magnetoresistive elements 10b to 10d), for the co-oriented fixed layer (fixed layer 11 of magnetoresistive element 10d) in which the magnetization is fixed in a first direction (X2 direction), a first spin hole portion (spin hole portion 20 of magnetoresistive element 10d) corresponding to the co-oriented fixed layer (fixed layer 11 of magnetoresistive element 10d) may be provided on the substrate, and in the first annealing, by energizing all the first spin hole portions (spin hole portions 20 corresponding to magnetoresistive elements 10a and 10d), the magnetic anisotropy of the first fixed layer (fixed layer 11 of magnetoresistive element 10a) and the co-oriented fixed layer (fixed layer 11 of magnetoresistive element 10d) may be fixed in the first direction (X2 direction).

[0069] In the above manufacturing method, there are three or more magnetoresistive elements (magnetoresistive elements 10b to 10d) provided on the substrate, and among the fixed layers (fixed layers 11) of the plurality of magnetoresistive elements (magnetoresistive elements 10b to 10d), for non-cooriented fixed layers (fixed layers 11 of magnetoresistive elements 10b and 10c) in which magnetization is fixed in a predetermined direction (for example, X1 direction) different from the first direction (X2 direction), the non-cooriented spin hole portion (magnetoresistive element 10b, 10c fixed layer) corresponding to the non-cooriented fixed layer (fixed layer 11 of magnetoresistive elements 10b and 10c) The spin hole portions 20 of the magnetoresistive elements 10b and 10c are provided on the substrate, and in the first annealing, by applying current to the non-symmetry spin hole portions (spin hole portions 20 of the magnetoresistive elements 10b and 10c), the magnetization (magnetization 11m) of the first fixed layer (fixed layer 11 of the magnetoresistive element 10a) and the symmetry fixed layer (fixed layer 11 of the magnetoresistive element 10d) is fixed in a first direction (X2 direction), and the magnetization (magnetization 11m) of the non-symmetry fixed layer (fixed layer 11 of the magnetoresistive elements 10b and 10c) may be fixed in a predetermined direction (X1 direction).

[0070] In this case, although the orientation in which the magnetization 11m of the non-conjoint fixed layer is fixed was the same as that of X1 in the above example, the manufacturing method including first annealing makes it possible to provide magnetoresistive elements capable of detecting a measurement magnetic field H along the Y direction, along with magnetoresistive elements 10a to 10d that detect a measurement magnetic field H along the X direction, on the same substrate by setting the magnetization 11m of a part of the non-conjoint fixed layer to be in the Y1 direction and Y2 direction.

[0071] In the above manufacturing method, the spin hole portion (first spin hole portion, second spin hole portion, non-symmetry spin hole portion) has a portion made of antiferromagnetic material on the side facing the stationary layer (first stationary layer, second stationary layer, symmetry stationary layer, non-symmetry stationary layer), and the stationary layer (first stationary layer, second stationary layer, symmetry stationary layer, non-symmetry stationary layer) and the spin hole portion (first spin hole portion, second spin hole portion, non-symmetry spin hole portion) may be magnetically coupled. In this case, before the start of the first annealing, an exchange coupling interaction may occur between the stationary layer (first stationary layer, second stationary layer, symmetry stationary layer, non-symmetry stationary layer) and the spin hole portion (first spin hole portion, second spin hole portion, non-symmetry spin hole portion).

[0072] In the above manufacturing method, a magnetic layer may be further provided between the stationary layers (first stationary layer, second stationary layer, concentric stationary layer, non-concentric stationary layer) and the spin hole portions (first spin hole portion, second spin hole portion, non-concentric spin hole portion).

[0073] The embodiments described above are provided to facilitate understanding of the present invention and are not intended to limit it. Accordingly, each element disclosed in the above embodiments is intended to include all design modifications and equivalents that fall within the technical scope of the present invention.

[0074] For example, in the above description, the initial magnetization 11mi of the fixed layer 11 was set by a magnetic field 20af based on exchange coupling interaction, but the invention is not limited to this. For example, in the configuration of the first example, if the direction of the initial magnetization 11mi does not depend on the direction in which the magnetization 11m of the fixed layer 11 is fixed (specifically, in the first example, all initial magnetizations 11mi are in the Z1 direction), the initial magnetization 11mi of the fixed layer 11 may be set by an externally applied magnetic field (specific examples include a magnetic field from a permanent magnet and an induced magnetic field). The initial magnetization 11mi of the fixed layer 11 only needs to be set when current is passed through the spin Hall portion 20 and a spin orbit torque is generated. That is, it only needs to be set immediately before the start of the first annealing, so in the first example, by applying an induced magnetic field in the Z1 direction to the entire substrate immediately before the start of the first annealing, and stopping the application of this induced magnetic field once the first annealing has started, the magnetization 11m of the fixed layer 11 can be fixed in a predetermined direction for all resistive elements provided on the substrate.

[0075] Furthermore, although the above description describes the provision of multiple magnetoresistive elements on the substrate, only one magnetoresistive element may be provided on the substrate. In this case as well, if a spin hole portion corresponding to the fixed layer of the magnetoresistive element provided on the substrate is provided, the magnetization of the fixed layer can be fixed in a predetermined direction without applying an external magnetic field.

[0076] The present invention is useful as a process for fixing the magnetization of the stationary layer of a magnetoresistive element in a method for manufacturing a magnetic sensor.

[0077] 1: Magnetic sensor 2: Magnetic field detection unit 3: Power supply unit 4: Magnetic field calculation unit 5: Amplifier 6: A / D conversion circuit 7: Control unit 10P: Detection center 10a, 10b, 10c, 10d: Magnetoresistive element 11m, 13m, 40m: Magnetization 11mi, 40mi: Initial magnetization 11: Fixed layer 12: Non-magnetic layer 13: Free magnetic layer 15: Full bridge circuit 20: Spin Hall section 20af: Magnetic field based on exchange coupling interaction 40: Magnetic layer 61: Control wiring 62: Measurement wiring 100a, 100b, 100c, 100d: Individual magnetic field detection unit 20ca, 20cb, 20cc, 20cd: Current 20sa, 20sb, 20sc, 20sd: Spin current GND: Ground terminal H: Measured magnetic field Hpx: External magnetic field Ia to Id: Control power supply V1, V2: Output terminals Vdd: Power supply terminal

Claims

1. A method for manufacturing a magnetic sensor comprising a first magnetoresistive element having a first fixed layer whose magnetization is fixed in a first direction on a substrate, and a first spin hole portion corresponding to the first fixed layer provided on the substrate, characterized in that the first fixed layer is formed, a first annealing is performed by heating while energizing the first spin hole portion to generate a spin orbit torque in the first spin hole portion, and the magnetization of the first fixed layer is fixed in a first direction based on the generated spin orbit torque.

2. The method for manufacturing a magnetic sensor according to claim 1, wherein the substrate is provided with a second magnetoresistive element having a second fixed layer in which magnetization is fixed in a second direction different from the first direction.

3. A method for manufacturing a magnetic sensor according to claim 2, wherein a second spin hole portion corresponding to the second fixed layer is provided in the substrate, and in the first annealing, current is also passed to the second spin hole portion to generate a spin-orbit torque in the second spin hole portion, the magnetic anisotropy of the second fixed layer is aligned to the second direction based on the generated spin-orbit torque, and the magnetization of the first fixed layer is fixed to the first direction and the magnetization of the second fixed layer is fixed to the second direction by the first annealing.

4. A method for manufacturing a magnetic sensor according to claim 2, wherein the magnetization of the first fixed layer is fixed in the first direction and the magnetization of the second fixed layer is fixed in the second direction by performing the first annealing while applying a magnetic field in the second direction.

5. A method for manufacturing a magnetic sensor according to any one of claims 2 to 4, comprising a half-bridge circuit having the first magnetoresistive element and the second magnetoresistive element.

6. A method for manufacturing a magnetic sensor according to any one of claims 2 to 4, comprising a full-bridge circuit having two first magnetoresistive elements and two second magnetoresistive elements.

7. A method for manufacturing a magnetic sensor comprising a first magnetoresistive element having a first fixed layer whose magnetization is fixed in a first direction, and a plurality of magnetoresistive elements having at least one fixed layer whose magnetization is fixed in a direction different from the first direction, all on the same substrate, wherein a first spin hole portion corresponding to the first fixed layer is provided on the substrate, characterized in that a spin orbit torque is generated in the first spin hole portion by performing a first annealing by heating while energizing the first spin hole portion, and the magnetization of the first fixed layer is fixed in a first direction based on the generated spin orbit torque.

8. The method for manufacturing a magnetic sensor according to claim 7, wherein, among the fixed layers of the plurality of magnetoresistive elements, the concentric fixed layer whose magnetization is fixed in the first direction has a first spin hole portion corresponding to the concentric fixed layer provided on the substrate, and in the first annealing, the magnetic anisotropy of the first fixed layer and the concentric fixed layer is fixed in the first direction by energizing all of the first spin hole portions.

9. The method for manufacturing a magnetic sensor according to claim 8, wherein there are three or more magnetoresistive elements provided on the substrate, and for non-symmetry fixed layers among the fixed layers of the plurality of magnetoresistive elements, the magnetization of a non-symmetry fixed layer is fixed in a predetermined direction different from the first direction, and a non-symmetry spin hole portion corresponding to the non-symmetry fixed layer is provided on the substrate, and in the first annealing, current is also passed to the non-symmetry spin hole portion to fix the magnetization of the first fixed layer and the symmetry fixed layer in the first direction, and the magnetization of the non-symmetry fixed layer in the predetermined direction.

10. The method for manufacturing a magnetic sensor according to claim 1 or claim 7, wherein the side of the first spin hole portion facing the first stationary layer has a portion made of an antiferromagnetic material, and the first stationary layer and the first spin hole portion are magnetically coupled.

11. The method for manufacturing a magnetic sensor according to claim 10, wherein, in the state prior to the start of the first annealing, an exchange coupling interaction occurs between the first stationary layer and the first spin Hall portion.

12. A method for manufacturing a magnetic sensor according to claim 1 or claim 7, further comprising a magnetic layer provided between the first fixed layer and the first spin hole portion.

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