JP2016072555A - Magnetic sensor and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic sensor and a method of manufacturing the magnetic sensor, capable of reducing a burden in a step of fixing a magnetization direction in a pinned layer.SOLUTION: A method of manufacturing a magnetic sensor includes: a deposition step of depositing a multilayer film including at least a pinned layer on inclined surfaces provided on a flat surface of a substrate 1W to constitute a plurality of magnetoresistance effect elements X1A, ..., Y1A, Y1B, ...; and a magnetization step of applying an external magnetic field having a vertical component orthogonal to the flat surface of the substrate 1W and a horizontal component parallel to the flat surface of the substrate 1W to fix a magnetization direction in each of pinned layers corresponding to at least a part of magnetoresistance effect elements X1A, ..., in the plurality of magnetoresistance effect elements, on the basis of the vertical component, as well as to fix a magnetization direction in each of pinned layers corresponding to the other magnetoresistance effect elements Y1A, Y1B, ..., in the plurality of magnetoresistance effect elements, on the basis of the horizontal component.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a magnetic sensor using a magnetoresistive effect element and a method for manufacturing the magnetic sensor.

  Conventionally, giant magnetoresistive elements (GMR (Giant Magneto Resistance) elements) are known as elements used in magnetic sensors. A so-called spin-valve magnetoresistive element includes a pinned layer whose magnetization is fixed (pinned) in a predetermined direction and a free layer whose magnetization direction changes according to an external magnetic field, and the magnetization direction of the pinned layer And the resistance value changes according to the relative relationship between the magnetization direction of the free layer. By electrically detecting the change in the resistance value, the strength of the external magnetic field (magnetic field) can be grasped.

  Further, as a method of manufacturing a magnetic sensor using such a magnetoresistive effect element, a regularized heat treatment is performed in which a heat treatment is performed while a magnet array in which permanent magnets are arranged in a matrix on a predetermined surface is superimposed on a semiconductor wafer (substrate). The process is known (for example, Patent Document 1). By superimposing a magnet array on a semiconductor wafer, an external magnetic field having regularity in a horizontal direction with respect to the flat surface can be applied to each of the matrix-like sections (that is, magnetic sensors) on the flat surface of the semiconductor wafer. it can. Thereby, the direction of magnetization of the pinned layer can be fixed to a desired direction based on the horizontal component of the external magnetic field for each of the plurality of magnetoresistive elements constituting the magnetic sensor.

JP 2007-212275 A

  As described above, in the step of fixing the magnetization direction of the pinned layer of the magnetoresistive effect element, a minute permanent is provided so as to correspond to each of the sections (magnetic sensors) arranged in a matrix on the flat surface of the semiconductor wafer. Since it is necessary to periodically arrange the magnets, it has been a burden to produce a magnet array that realizes such an arrangement of permanent magnets with high accuracy.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a magnetic sensor and a method of manufacturing the magnetic sensor that can reduce the burden in the step of fixing the magnetization direction of the pinned layer.

One embodiment of the present invention is a film forming step of forming a multilayer film including a plurality of magnetoresistive elements and including at least a pinned layer on an inclined surface provided on a flat surface of the substrate, and the flat surface of the substrate Applying an external magnetic field having a vertical component perpendicular to the horizontal plane and a horizontal component parallel to the flat surface of the substrate, and based on the vertical component, at least some of the magnetoresistance effect elements of the plurality of magnetoresistance effect elements The magnetization direction of the pinned layer corresponding to the element is fixed and, based on the horizontal component, corresponding to another magnetoresistive element different from the part of the plurality of magnetoresistive elements. And a magnetization step for fixing the magnetization direction of the pinned layer.
By doing so, it is possible to fix the magnetization direction of the pinned layer with a vertical component that can be accurately applied to a desired direction without downsizing the magnet used for applying the external magnetic field. Therefore, the magnetization direction of the pinned layer can be accurately fixed to a desired direction without downsizing the magnet. In addition, since the magnetization direction of the pinned layer corresponding to the plurality of magnetoresistive elements is fixed based on the vertical component orthogonal to the flat surface of the substrate and the horizontal component parallel to the flat surface of the substrate, the pinned layer Can be fixed in a plurality of different directions. Therefore, since a plurality of magnetoresistive effect elements having different sensitivity directions can be formed, the external magnetic field to be measured can be measured for each component in a plurality of different directions.

In one embodiment of the present invention, in the film forming step of the magnetic sensor manufacturing method described above, the multilayer film is provided on an inclined surface provided for each of a plurality of sections arranged side by side on the flat surface of the substrate. In the first step, the magnetization direction of the pinned layer is based on the perpendicular component in the first region arranged in the center among the three regions divided by parallel straight lines in the magnetization step. In the second region and the third region arranged on both sides of the first region of the section, the magnetization direction of the pinned layer is fixed based on the horizontal component and applied to the second region. The azimuth of the horizontal component and the azimuth of the horizontal component applied to the third region are opposite to each other.
By doing so, it is possible to form pinned layers whose magnetization directions are opposite to each other in the second region and the third region in one section. Therefore, a magnetic sensor with high detection accuracy can be manufactured by combining a magnetoresistive effect element having pinned layers whose magnetization directions are opposite to each other to form a bridge circuit.
Further, according to such a method of manufacturing a magnetic sensor, the magnetization direction of the pinned layer belonging to the first region arranged in the center among the three regions in which one section is divided by two parallel straight lines is set to the outside. While fixing with the vertical component of the magnetic field, the magnetization directions of the pinned layers belonging to the second region and the third region arranged on both sides thereof are fixed with the horizontal components of the external magnetic field in opposite directions. In this way, only one polar face of a single magnet is opposed to one section and an external magnetic field generated radially from the polar face is desired for all of the first to third areas. It is possible to apply an external magnetic field of the orientation. Therefore, it is possible to reduce the number of polar surfaces of the magnets facing the one section.

Further, according to one aspect of the present invention, in the magnetization step of the magnetic sensor manufacturing method described above, for each of the plurality of sections arranged in one direction on the flat surface of the substrate, The external magnetic field is applied using a bar magnet extending in one direction.
By doing in this way, it is possible to apply an external magnetic field to each of a plurality of sections arranged side by side in one direction by using the bar magnet extending in the one direction. Therefore, since it is not necessary to arrange minute magnets so as to correspond to each of a plurality of sections, the burden on the magnetization step can be reduced.
Further, according to such a method of manufacturing a magnetic sensor, since the bar magnets are arranged so as to extend in parallel with the direction in which the sections are arranged side by side, the bar magnets are spread over the entire range of the sections. A uniform external magnetic field is applied that travels straight in the direction perpendicular to the extending direction. Therefore, it is possible to eliminate a component that curves in an arc on the flat surface of the substrate from the external magnetic field applied by the bar magnet. Therefore, the magnetization direction of the pinned layer disposed in the second region and the third region can be accurately fixed to a desired direction based on the horizontal component of the external magnetic field.

In one aspect of the present invention, in the magnetizing step of the magnetic sensor manufacturing method, the bar magnet has a polar surface of the bar magnet facing the first region in each of the plurality of sections. However, it extends in the one direction.
By doing in this way, the pinned layer which belongs to each 1st area | region of a some division is distribute | arranged to the position facing the polar surface of a bar magnet. As a result, an external magnetic field having a strong vertical component that is a magnetic field generated in the normal direction of the polar surface of the bar magnet can be applied to the pinned layer. Therefore, the magnetization direction of the pinned layer can be accurately fixed to a desired direction based on the vertical component of the external magnetic field.

Further, according to one aspect of the present invention, in the magnetizing step of the magnetic sensor manufacturing method described above, the bar magnet is a first magnet that faces one polar face to the first region in one section. And the second magnet, which is the bar magnet and opposite to the first region in the other section adjacent to the one section, is arranged on the same plane, and the external magnetic field is It is characterized by applying.
By doing in this way, the pinned layer belonging to each of the second region and the third region of each of the plurality of sections has the first magnet facing one polar surface in the in-plane direction of the flat surface of the substrate, and the other It arrange | positions between the 2nd magnets which make a polar surface oppose. Thereby, an external magnetic field having a strong horizontal component, which is a magnetic field generated between the polar face of the first magnet and the polar face of the second magnet, can be applied to the pinned layer. Therefore, the magnetization direction of the pinned layer can be accurately fixed to a desired direction based on the horizontal component of the external magnetic field.

According to another aspect of the present invention, in the film forming step of the magnetic sensor manufacturing method described above, the pinned layer is provided so as to be in contact with the flat surface along a first direction in an in-plane direction of the flat surface. The film is formed on both the first inclined surface and the second inclined surface provided so as to be in contact with the flat surface along a second orientation different from the first orientation.
In this way, in the manufactured magnetic sensor, a plurality of magnetoresistive effect elements having different sensitivity directions in the in-plane direction of the flat surface are formed, so that the external magnetic field is measured for each component of different orientations. A possible magnetic sensor can be manufactured.

One embodiment of the present invention includes a rectangular plate-shaped main body portion and at least a pinned layer, and an inclined surface of a first inclined surface provided along a first orientation in an in-plane direction of the flat surface of the main body portion. Further, the first magnetoresistive element formed with the first orientation as the longitudinal direction, and at least a pinned layer, is an orientation in the in-plane direction of the flat surface of the main body and is different from the first orientation. A second magnetoresistive element formed on the inclined surface of the second inclined surface provided along two azimuths with the second azimuth as the longitudinal direction, and the flat surface of the main body portion is the main body The first magnetoresistive element is arranged in the first region arranged in the center among the three regions divided by the straight line parallel to one side of the part, and the second region arranged on both sides of the first region. In each of the region and the third region, the second magnetoresistance effect element A magnetic sensor, characterized in that is disposed.
In this way, in the magnetic sensor manufacturing process, when a plurality of rectangular plate-shaped main body portions are arranged in one direction on the substrate as one section, the first region to the first region on the flat surface of the substrate are arranged. It is possible to connect the third regions in a single direction and connect them in a row. Therefore, the pinning in the first magnetoresistive effect element and the second magnetoresistive effect element is applied to each of the first region to the third region while applying an external magnetic field collectively using the bar magnet extending in the one direction. Since the magnetization direction of the layer can be fixed, the work load in the manufacturing process of the magnetic sensor can be reduced.

According to another aspect of the present invention, in the above-described magnetic sensor, the first magnetoresistive element disposed in the first region has a magnetization direction of the pinned layer at least perpendicular to the flat surface. The second magnetoresistive element arranged in the second region has a component in which the magnetization direction of the pinned layer faces at least one direction parallel to the flat surface. The second magnetoresistive element disposed in the third region has a component in which the magnetization direction of the pinned layer is directed to at least another direction parallel to the flat surface. .
In this way, a magnetic sensor with high detection accuracy can be manufactured by configuring a bridge circuit by combining magnetoresistive elements having pinned layers whose magnetization directions are opposite to each other in one section. it can.

  One embodiment of the present invention is the above-described magnetic sensor, wherein the first magnetoresistive element and the second magnetoresistive element have a flat surface of the main body portion, the first region, and the second region. The region and the third region are arranged on one side of two regions that are divided into two equal parts so as to be orthogonal to a boundary line that divides each of the third region and the third region.

  According to the magnetic sensor and the method for manufacturing the magnetic sensor described above, it is possible to reduce the burden in the step of fixing the magnetization direction of the pinned layer.

It is a figure showing the whole magnetic sensor composition concerning a 1st embodiment. It is a 1st figure which shows the structure of the magnetic sensor which concerns on 1st Embodiment. It is a 2nd figure which shows the structure of the magnetic sensor which concerns on 1st Embodiment. It is a figure explaining the outline | summary of the ordered heat treatment process which concerns on 1st Embodiment. It is a figure which shows the arrangement | positioning relationship between the division on a board | substrate and the magnet array in the regularization heat treatment process which concerns on 1st Embodiment. It is a 1st figure explaining the mode of the external magnetic field applied in the regularization heat treatment process which concerns on 1st Embodiment. It is a 2nd figure explaining the mode of the external magnetic field applied in the regularization heat treatment process which concerns on 1st Embodiment. It is a 3rd figure explaining the mode of the external magnetic field applied in the ordered heat treatment process which concerns on 1st Embodiment. It is a 4th figure explaining the mode of the external magnetic field applied in the regularization heat treatment process which concerns on 1st Embodiment. It is a figure explaining the azimuth | direction of magnetization of the pinned layer of the magnetic sensor which concerns on 1st Embodiment. It is a figure explaining the circuit structure of the magnetic sensor which concerns on 1st Embodiment. It is a 1st figure explaining the manufacturing method of the magnetic sensor which concerns on the comparison of 1st Embodiment. It is a 2nd figure explaining the manufacturing method of the magnetic sensor which concerns on the comparison of 1st Embodiment. It is a figure explaining the effect of the manufacturing method of the magnetic sensor concerning a 1st embodiment. It is a figure explaining the outline | summary of the regularization heat treatment process which concerns on the modification of 1st Embodiment.

<First Embodiment>
[Magnetic sensor structure]
Hereinafter, the magnetic sensor and the manufacturing method thereof according to the first embodiment will be described.
The magnetic sensor according to this embodiment measures the magnetic field strength of an external magnetic field applied from the outside for each component (Hx, Hy, Hz) of three axes (± X direction, ± Y direction, ± Z direction) orthogonal to each other. A possible three-axis magnetic sensor.

FIG. 1 is a diagram illustrating an overall configuration of the magnetic sensor according to the first embodiment.
As shown in FIG. 1, the magnetic sensor 1 includes a rectangular plate-shaped main body (section 1a) and twelve magnetoresistive elements X1A, X1C, X2A, X2C, Y1A, Y1B, Y1C, Y1D, Y2A, Y2B. , Y2C, and Y2D.
The main body (section 1a) of the magnetic sensor 1 is composed of one section of the flat surface of the substrate 1W that is a semiconductor wafer. The magnetic sensor 1 is manufactured by forming magnetoresistive elements X1A to Y2D and various circuits for each of a plurality of sections including the section 1a on the flat surface of the substrate 1W, and then dividing the section into the sections. Although not shown in FIG. 1, in the manufacturing process of the magnetic sensor 1, a plurality of sections including the section 1 a are arranged in a matrix while adjoining each other on the flat surface of the substrate 1 </ b> W. It is arranged. In the present embodiment, the plurality of sections including the section 1a are about 1 mm square.

The twelve magnetoresistive elements X1A to Y2D are all formed on inclined surfaces (first inclined surfaces 10a, 10b, second inclined surfaces 10c, 10d) that are inclined with respect to the flat surface of the substrate 1W.
The four magnetoresistive elements X1A, X1C, X2A, and X2C (first magnetoresistive elements) are oriented in the in-plane direction of the flat surface of the section 1a and in a first direction (parallel to one side of the section 1a). On the inclined surfaces of the first inclined surfaces 10a and 10b provided so as to be in contact with the flat surface along the (± Y direction), the first direction is formed as the longitudinal direction.
In addition, the eight magnetoresistive elements Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C, and Y2D (second magnetoresistive elements) are oriented in the in-plane direction of the flat surface of the section 1a and are the first. On the inclined surfaces of the second inclined surfaces 10c and 10d provided so as to be in contact with the flat surface along the second direction (± X direction) orthogonal to the direction, the second direction is formed as the longitudinal direction. .

Further, the magnetic sensor 1 includes four magnetoresistive elements in the first region A1 arranged in the center among the three regions in which the flat surface of the partition 1a is partitioned by two straight lines parallel to one side of the partition 1a. Effect elements X1A, X1C, X2A, X2C (first magnetoresistance effect elements) are arranged.
The magnetic sensor 1 includes eight magnetoresistive elements Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C in each of the second region A2 and the third region A3 arranged on both sides of the first region A1. , Y2D (second magnetoresistive element) is arranged. Specifically, the magnetoresistive effect elements Y1A, Y1C, Y2B, and Y2D among the second magnetoresistive effect elements are provided in the second region A2. The third region A3 is provided with magnetoresistive elements Y1B, Y1D, Y2A, and Y2C among the second magnetoresistive elements.

Further, the magnetoresistive effect elements X1A and X1C are on the first inclined surface 10a of the first inclined surfaces 10a and 10b, which is inclined so as to rise from the −X direction side to the + X direction side (go to the + Z direction side). It is formed. On the other hand, the magnetoresistive effect elements X2A and X2C are on the first inclined surface 10b that is inclined so as to descend from the −X direction side to the + X direction side (advance toward the −Z direction side) of the first inclined surfaces 10a and 10b. Formed.
Similarly, the magnetoresistive elements Y1A, Y1B, Y1C, and Y1D are inclined such that the second inclined surfaces 10c and 10d are lowered from the −Y direction side to the + Y direction side (going to the −Z direction side). 2 formed on the inclined surface 10c. On the other hand, the magnetoresistive elements Y2A, Y2B, Y2C, and Y2D are second slopes that slope so as to rise (go to the + Z direction side) from the −Y direction side to the + Y direction side among the second inclined surfaces 10c and 10d. Formed on the surface 10d.

FIG. 2 is a first diagram illustrating the structure of the magnetic sensor according to the first embodiment.
Specifically, FIG. 2 is a diagram schematically showing a cross-sectional structure of α-α ′ in FIG. As shown in FIG. 2, a groove 10 is formed on the flat surface of the substrate 1W. The groove 10 is formed by processing a part of the flat surface of the substrate 1W through a predetermined manufacturing process (film formation, resist coating, patterning, and etching steps).
As shown in FIG. 2, the groove 10 has first inclined surfaces 10a and 10b inclined at a predetermined inclination angle θ (eg, θ = 45 °) with respect to the flat surface of the substrate 1W. The groove portion 10 (that is, the first inclined surfaces 10a and 10b) extends along the depth direction of the paper surface (first azimuth (± Y direction)), and the magnetoresistive effect element X1A is on the first inclined surface 10a. The magnetoresistive effect element X2A is formed on the first inclined surface 10b so that the first direction (± Y direction) is the longitudinal direction.
In addition to the magnetoresistive effect element X1A and the magnetoresistive effect element X2A shown in FIG. 2, the magnetoresistive effect element X1C and the magnetoresistive effect element X2C are similarly formed on the first inclined surfaces 10a and 10b, respectively.

  Although not shown in detail, the second inclined surfaces 10 c and 10 d shown in FIG. 1 are formed by groove portions similar to the groove portions 10. The grooves (that is, the second inclined surfaces 10c and 10d) are formed so as to extend along the second direction (± X direction), and the magnetoresistive elements Y1A, Y1B, Y1C, and Y1D have the second inclination. On the surface 10c, magnetoresistive elements Y2A, Y2B, Y2C, Y2D are formed on the second inclined surface 10d so that the second direction (± X direction) is the longitudinal direction (see FIG. 1). ).

  In the present embodiment, the inclination angle θ of the first inclined surfaces 10a, 10b and the second inclined surfaces 10c, 10d is assumed to be θ = 45 °, and in the following description, the first inclined surface 10a. Is defined as the ± X ′ axis, and the normal direction of the first inclined surface 10a is defined as the ± Z ′ axis. However, in other embodiments, the inclination angle θ of the first inclined surfaces 10a, 10b and the second inclined surfaces 10c, 10d is not limited to θ = 45 °.

FIG. 3 is a second diagram illustrating the structure of the magnetic sensor according to the first embodiment.
Specifically, FIG. 3 is a diagram illustrating a specific structure of the magnetoresistive element X1A shown in FIG. The structure of the other eleven magnetoresistive elements X2A to Y2D is the same as the structure of the magnetoresistive element X1A, and thus the description thereof is omitted.

3A is a schematic diagram when the magnetoresistive element X1A is viewed in plan from the + Z ′ direction side (see FIG. 2), and FIG. 3B is a diagram of β-β ′ in FIG. FIG.
As shown in FIG. 3A, the magnetoresistive element X1A has a rectangular shape in plan view, and is arranged so that its longitudinal direction is along the first direction (± Y direction). The magnetoresistive element X1A is electrically connected to an external circuit by the wiring layers 31a and 31b. For example, positive and negative electrodes of a constant voltage source (not shown) are connected to the wiring layers 31a and 31b, respectively. In response to application of a predetermined power supply voltage Vin + (for example, 3V) and ground voltage Vin− (for example, 0V) by the constant voltage source, the wiring layer 31a (wiring layer 31b) via the magnetoresistive effect element X1A A current flows to 31b (wiring layer 31a).

As shown in FIG. 3B, the magnetoresistive element X1A includes a pinning layer 30a made of an antiferromagnetic material, a pinned layer 30b whose magnetization direction is fixed by the pinning layer 30a, and a spacer layer 30c made of a nonmagnetic material. , And a free layer 30d in which the direction of magnetization changes according to the external magnetic field is laminated to form a spin valve structure.
With this spin valve structure, the magnetoresistive effect element X1A can detect the strength of the external magnetic field by changing the resistance value between the wiring layer 31a and the wiring layer 31b according to the external magnetic field to be measured.
Note that the structure of the magnetoresistive effect element X1A shown in FIGS. 3A and 3B is an example, and the structure can be appropriately changed as long as the function of the spin valve can be exhibited. For example, the film formation order of the free layer 30d, the pinned layer 30b, and the pinning layer 30a can be interchanged, and further layers other than those described above may be inserted to improve characteristics as a magnetoresistive effect element. .
In addition, as for materials, film forming conditions, and the like used for each of the pinning layer 30a, the pinned layer 30b, the spacer layer 30c, and the free layer 30d, a detailed description is omitted because known manufacturing techniques can be applied. A regularizing heat treatment step (magnetization step) for fixing the magnetization direction of the pinned layer 30b to a desired direction will be described later.

The magnetoresistive effect element X1A is manufactured so that the magnetization direction of the pinned layer 30b is fixed in a predetermined direction (+ X ′ direction) by a regularization heat treatment step to be described later (FIG. 3A). .
Further, the magnetoresistive element X1A has a specific direction in which the magnetization direction of the free layer 30d is based on the shape of the free layer 30d in a state where the external magnetic field to be measured does not exist (hereinafter also referred to as “initial state”). It is formed to face the direction. Specifically, the free layer 30d is formed into a rectangular shape in plan view, and the magnetization anisotropy of the free layer 30d is aligned with the longitudinal direction (+ Y direction) of the rectangular shape using the shape anisotropy. (See FIGS. 3A and 3B).

[Regularized heat treatment process]
FIG. 4 is a diagram for explaining the outline of the ordered heat treatment process according to the first embodiment.
The ordered heat treatment step is a step of fixing the magnetization direction of the pinned layer 30b (FIG. 3) of the magnetoresistive elements X1A to Y2D (FIG. 1) to a desired direction.
Here, the process before the regularization heat treatment process will be briefly described. First, formation of grooves (grooves 10 and the like (see FIG. 2)) is made for each flat surface section (section 1a and the like) of the substrate 1W. Perform the steps. For example, in the formation step, first, an oxide film (for example, a film thickness of 5 μm) made of a SiO ₂ film is formed by CVD (Chemical Vapor Deposition) or the like, and then a resist is applied to the upper layer to form a resist film (for example, , A film thickness of 5 μm) is formed. Then, the resist film is subjected to pattern cutting according to the arrangement pattern of the groove portions 10 and the like, and then the resist film is formed into a tapered shape (tapered) by heat treatment or the like. Thereafter, dry etching is performed under conditions where the oxide film and the resist film are etched at substantially the same ratio. Thereby, as shown in FIG. 2, the groove part 10 which has 1st inclined surface 10a, 10b is formed.
Thereafter, the multilayer film constituting the magnetoresistive elements X1A to Y2D (FIG. 1), that is, the pinning layer 30a, the pinned layer 30b, the spacer layer 30c, and the free layer 30d (FIG. 3) is formed on the inclined surface by using a sputtering method or the like. A film forming step is sequentially performed on the first inclined surfaces 10a and 10b and the second inclined surfaces 10c and 10d (FIG. 1). The inclined surface is provided for each of a plurality of sections (sections 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i (FIG. 5)) arranged side by side on the flat surface of the substrate 1W. Yes.

  In addition, the specific process of the formation step described above is merely an example, and any other mode is possible as long as a desired inclined surface can be formed on the flat surface of the semiconductor wafer (substrate 1W). It doesn't matter. For example, in the formation step of the magnetic sensor 1 according to the present embodiment, the first inclined surfaces 10a and 10b and the second inclined surface 10c are formed by forming the groove portions 10 that are recessed downward (−Z direction) from the flat surface of the substrate 1W. 10d is provided, but is not limited to this in other embodiments. For example, in the formation step of the magnetic sensor 1 according to another embodiment, the first inclined surfaces 10a and 10b and the second inclined surface 10c are formed by forming a bank portion protruding upward (+ Z direction) from the flat surface of the substrate 1W. 10d may be provided.

Next, a regularized heat treatment step (magnetization step) for fixing the magnetization direction of the pinned layer 30b is performed.
As shown in FIG. 4, in the regularized heat treatment process, the pinned layer 30b is formed on the first inclined surfaces 10a and 10b and the second inclined surfaces 10c and 10d (FIGS. 1 and 2) through the formation step and the film forming step. A substrate 1 </ b> W on which a multilayer film (FIG. 3) is formed is overlaid on a magnet array 20 prepared in advance. In the magnet array 20, permanent bar magnets (first magnet 20N and second magnet 20S described later) are regularly arranged so as to correspond to each of the sections (section 1a and the like) arranged on the flat surface of the substrate 1W. The jigs are arranged on the same plane.
In the ordering heat treatment step, as shown in FIG. 4, the back surface of the substrate 1W (a surface different from the flat surface on which the magnetoresistive effect elements X1A to Y2D are formed) is opposed to the flat surface of the magnet array 20. Overlay and fix both. At this time, the alignment is performed so that each section on the flat surface of the substrate 1W corresponds to the arrangement pattern of the permanent bar magnets (first magnet 20N, second magnet 20S) in the magnet array 20.
While maintaining this state, by heating in vacuum, the magnetization direction of each pinned layer 30b is fixed to the direction corresponding to the external magnetic field applied by each permanent bar magnet (precisely, the heat treatment). Thereby, the magnetization direction of the pinning layer 30a is fixed, and the magnetization direction of the pinned layer 30b is fixed based on the interaction with the pinning layer 30a whose magnetization is fixed.

FIG. 5 is a diagram showing an arrangement relationship between the partitions on the substrate and the magnet array in the ordered heat treatment process according to the first embodiment.
As shown in FIG. 5, the magnet array 20 includes a first magnet 20 </ b> N that makes the N-polar surface (one polar surface) face the back surface of the substrate 1 </ b> W, and an S-pole surface (others) The second magnets 20S that are opposed to each other in the polar plane) are arranged in parallel and alternately on the same plane.

The first magnet 20N and the second magnet 20S extend in the second direction with respect to each of a plurality of sections (for example, sections 1a, 1b, and 1c) arranged side by side in the second direction (± X direction). It is a bar magnet arranged to do.
The first magnet 20N and the second magnet 20S, which are bar magnets, extend in one direction in which the plurality of sections are arranged side by side while facing the first region A1 in each of the plurality of sections (sections 1a to 1i). Arranged to exist. Further, the first magnet 20N is arranged so that the polar surface of the N pole faces the first region A1 in one section (for example, the section 1a), and the second magnet 20S is arranged in one section (section 1a). ) Is arranged so that the polar face of the S pole faces the first region A1 in the other sections (sections 1d, 1g) adjacent to.

  More specifically, the polar surfaces of the first magnet 20N facing the N-pole surfaces are arranged in the sections 1a, 1b, 1c so as to overlap the first areas A1 of the sections 1a, 1b, 1c. It is arranged to extend along. Similarly, the polar surface of the second magnet 20S that faces the S pole surface is the first of each of the sections 1d, 1e, and 1f adjacent to each of the sections 1a, 1b, and 1c in the first orientation (± Y direction). It is arranged so as to extend along the arrangement of the sections 1d, 1e, and 1f so as to overlap the area A1. In addition, the polar surface of the second magnet 20S disposed on the other side of the first magnet 20N is divided into the sections 1g, 1h, 1i is arranged so as to extend along the arrangement of the sections 1g, 1h, 1i so as to overlap each first region A1 of 1i.

In the magnetic sensor 1 according to the present embodiment, the center position of the polar surface of the first magnet 20N in the width direction (± Y direction) is arranged in the first region A1 of each of the sections 1a, 1b, and 1c. The resistor elements X1A, X1C, X2A, and X2C are arranged so as to overlap. More specifically, the first magnet 20N includes the center position O1 in the longitudinal direction (± Y direction) of the magnetoresistive effect elements X1A, X1C, X2A, and X2C and the width direction (± of the polar surface of the first magnet 20N). The center position O2 in the (Y direction) is arranged to coincide with the first orientation (± Y direction).
Similarly, in the second magnet 20S, the central position in the width direction (± Y direction) of the polar surface of the second magnet 20S is the first position of each of the sections 1d, 1e, 1f (or sections 1g, 1h, 1i). The magnetoresistive effect elements X1A, X1C, X2A, and X2C arranged in one area A1 are arranged so as to overlap.

  As described above, in the magnet array 20 according to the present embodiment, the first magnet 20N and the second magnet arranged as described above with respect to all the sections (sections 1a to 1i) arranged on the flat surface of the substrate 1W. The magnets 20S are periodically and alternately arranged in parallel with the second direction (± X direction). As a result, the first region A1 of all the sections arranged in a matrix on the flat surface of the substrate 1W includes either the N pole surface of the first magnet 20N or the S pole surface of the second magnet 20S. Either one is opposite.

FIG. 6 is a first diagram for explaining a state of an external magnetic field applied in the ordered heat treatment process according to the first embodiment.
As shown in FIG. 6, in the ordered heat treatment step, the magnet array 20 is disposed below the substrate 1W (in the −Z direction). The first magnet 20N provided in the magnet array 20 is arranged so that the polar surface of the N pole faces the back surface of the substrate 1W, and the second magnet 20S makes the polar surface of the S pole face the back surface of the substrate 1W. Is arranged. In FIG. 6, as an example, only the section 1a and the sections 1d and 1g adjacent to the section 1a in the first direction (± Y direction) are illustrated, but other sections (sections 1b, 1e, 1h, The sections 1c, 1f, 1i, etc.) are also arranged in the same positional relationship.

  In the sections 1a, 1d, and 1g, first inclined surfaces 10a and 10b and second inclined surfaces 10c and 10d, on which the magnetoresistive effect elements X1A to Y2D are formed through the manufacturing process, are formed. The polar area of the N pole of the first magnet 20N is opposed to the first region A1 where the first inclined surfaces 10a and 10b are formed in the section 1a. Similarly, the polar area of the south pole of the second magnet 20S faces the first region A1 of the sections 1d and 1g.

  On the other hand, both polar surfaces of the first magnet 20N and the second magnet 20S are opposed to the second region A2 and the third region A3 where the second inclined surfaces 10c, 10d are formed in the sections 1a, 1d, 1g. Not. The second region A2 and the third region A3 extend in the second direction (± X direction) while facing the first region A1 of each of the partitions 1a, 1d, and 1g adjacent to the first direction (± Y direction). It is arranged between the existing first magnet 20N and the second magnet 20S.

The first magnet 20N and the second magnet 20S are arranged as shown in FIGS. 5 and 6 with respect to the substrate 1W, whereby the pinned layer 30b arranged on the flat surface of the substrate 1W has a first magnet. An external magnetic field H is applied that travels from the N polar face of 20N to the S polar face of the second magnet 20S. Specifically, the external magnetic field H travels upward (+ Z direction) from the polar face of the N pole of the first magnet 20N and draws an arc so that the polarity of the S pole of the adjacent second magnet 20S is drawn. The light enters the surface downward (−Z direction).
By doing in this way, the magnetization direction of the pinned layer 30b belonging to the first region A1 of each of the sections 1a to 1i is fixed based on the vertical component orthogonal to the substrate 1W of the external magnetic field H. Further, the magnetization direction of the pinned layer 30b belonging to the second region A2 and the third region A3 is fixed based on a horizontal component parallel to the flat surface of the substrate 1W of the external magnetic field H. Furthermore, the azimuth of the horizontal component of the external magnetic field H applied to the second region A2 and the azimuth of the horizontal component of the external magnetic field H applied to the third region A3 are opposite to each other.
Hereinafter, the orientation of the external magnetic field H applied to each of the first region A1, the second region A2, and the third region A3, and the magnetization orientation of the pinned layer 30b belonging to each of the first region A1 to the third region A3. Will be described in detail with reference to FIGS.

FIG. 7 is a second diagram for explaining the state of the external magnetic field applied in the ordered heat treatment process according to the first embodiment.
FIG. 7 shows, in detail, the vicinity of the groove 10 in which the magnetoresistive effect elements X1A and X2A belonging to the first region A1 (FIGS. 5 and 6) in the partition 1a are formed. Below the position where the magnetoresistive effect elements X1A and X2A are arranged (in the −Z direction), the polar face of the N pole of the first magnet 20N is arranged. Therefore, the magnetoresistive effect elements X1A and X2A include An external magnetic field H facing upward (+ Z direction) is applied (see FIG. 7). The pinned layer 30b (not shown in FIG. 7) of the magnetoresistive effect elements X1A and X2A formed on the first inclined surfaces 10a and 10b is heated with an external magnetic field H directed upward. Thus, the direction of each magnetization is fixed so as to have a component in the + Z direction (vertical component).

Specifically, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element X1A) formed on the first inclined surface 10a is the in-plane direction of the first inclined surface 10a. And fixed in the direction c1 (+ X ′ direction) having a component in the + Z direction. Similarly, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element X2A) formed on the first inclined surface 10b is the in-plane direction of the first inclined surface 10b and + Z It is fixed to the direction c2 (+ Z ′ direction) having a direction component. Here, the pinned layer 30b formed on the first inclined surface 10a is inclined so as to rise from the −X direction to the + X direction (toward the + Z direction). Therefore, the magnetization direction c1 of the pinned layer 30b has a + Z direction component and a + X direction component. In contrast to the first inclined surface 10a, the pinned layer 30b formed on the first inclined surface 10b is inclined so as to rise from the + X direction to the -X direction (toward the + Z direction). Therefore, the magnetization direction c2 of the pinned layer 30b has a + Z direction component and a -X direction component.
As for the other magnetoresistive elements X1C and X2C to which the upper external magnetic field H is applied, the first inclined surfaces 10a and 10b formed respectively, similarly to the magnetoresistive elements X1A and X2A shown in FIG. The magnetization is fixed in the in-plane direction and having an orientation in the + Z direction.

FIG. 8 is a third diagram illustrating the state of the external magnetic field applied in the ordered heat treatment process according to the first embodiment. In the following description of FIGS. 8 and 9, the inclination direction of the second inclined surface 10 c is defined as the ± Y ′ axis, and the normal direction of the second inclined surface 10 c is defined as the ± Z ″ axis.
FIG. 8 shows in detail the vicinity of the groove 10 where the magnetoresistive effect elements Y1A and Y2B belonging to the second region A2 (FIGS. 5 and 6) in the partition 1a are formed. The magnetoresistive elements Y1A and Y2B formed on the second inclined surfaces 10c and 10d are in the vicinity of an intermediate position between the N-polar polarity surface of the first magnet 20N and the S-polarity surface of the second magnet 20S, that is, In the vicinity of the boundary between the partition 1a and the partition 1g (see FIG. 6). Therefore, the magnetoresistive elements Y1A and Y2B are horizontal (one direction in the first direction (+ Y direction)) from the N-polarity plane of the first magnet 20N toward the S-polarity plane of the second magnet 20S. An external magnetic field H that goes to is applied (see FIG. 8). The pinned layer 30b (not shown in FIG. 8) of the magnetoresistive elements Y1A and Y2B formed on the second inclined surfaces 10c and 10d has an external magnetic field H that faces one direction (+ Y direction) in the first direction. By being heated in a state where is applied, the direction of magnetization is fixed so as to have a component in the + Y direction.

Specifically, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element Y1A) formed on the second inclined surface 10c is the in-plane direction of the second inclined surface 10c. And fixed in the direction d1 (+ Y ′ direction) having a component in the + Y direction. Similarly, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element Y2B) formed on the second inclined surface 10d is the in-plane direction of the second inclined surface 10d and + Y The direction d4 (+ Z ″ direction) having a directional component is fixed. Here, the pinned layer 30b formed on the second inclined surface 10c is inclined so as to descend from the −Y direction to the + Y direction (toward the −Z direction). Therefore, the magnetization direction d1 of the pinned layer 30b has a + Y direction component and a -Z direction component. In contrast to the second inclined surface 10c, the pinned layer 30b formed on the second inclined surface 10d is inclined so as to rise from the −Y direction to the + Y direction (toward the + Z direction). Therefore, the magnetization direction d4 of the pinned layer 30b has a component in the + Y direction and a component in the + Z direction.
In addition, each of the other magnetoresistive elements Y1C and Y2D to which the external magnetic field H in one direction (+ Y direction) in the first direction is applied is also similar to the magnetoresistive elements Y1A and Y2B shown in FIG. Magnetization is fixed in an in-plane direction of the formed second inclined surfaces 10c and 10d and having an + Y-direction component.

FIG. 9 is a fourth diagram illustrating the state of the external magnetic field applied in the ordered heat treatment process according to the first embodiment.
FIG. 9 shows in detail the vicinity of the groove 10 where the magnetoresistive elements Y1B and Y2A belonging to the third region A3 (FIGS. 5 and 6) in the partition 1a are formed. The magnetoresistive elements Y1B and Y2A formed on the second inclined surfaces 10c and 10d are in the vicinity of an intermediate position between the N-polar polarity surface of the first magnet 20N and the S-polarity surface of the second magnet 20S, that is, In the vicinity of the boundary between the section 1a and the section 1d (see FIG. 6). Therefore, the magnetoresistive effect elements Y1B and Y2A are horizontally oriented from the N-polarity plane of the first magnet 20N toward the S-polarity plane of the second magnet 20S (other orientations in the first orientation (−Y direction)). ) Is applied (see FIG. 9). The pinned layer 30b (not shown in FIG. 9) of the magnetoresistive effect elements Y1B and Y2A formed on the second inclined surfaces 10c and 10d is an external magnetic field that faces another direction (−Y direction) in the first direction. By heating in a state where H is applied, the direction of magnetization is fixed so as to have a component in the -Y direction.

Specifically, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element Y1B) formed on the second inclined surface 10c is the in-plane direction of the second inclined surface 10c. And fixed in the direction d3 (−Y ′ direction) having a component in the −Y direction. Similarly, the magnetization direction of the pinned layer 30b (that is, the pinned layer 30b constituting the magnetoresistive effect element Y2A) formed on the second inclined surface 10d is the in-plane direction of the second inclined surface 10d − It is fixed in the direction d2 (−Z ″ direction) having a component in the Y direction. Here, the pinned layer 30b formed on the second inclined surface 10c is inclined so as to rise from the + Y direction to the -Y direction (toward the + Z direction). Therefore, the magnetization direction d3 of the pinned layer 30b has a component in the -Y direction and a component in the + Z direction. Further, the pinned layer 30b formed on the second inclined surface 10d is inclined so as to descend from the + Y direction to the -Y direction (towards the -Z direction), contrary to the second inclined surface 10c. . Therefore, the magnetization direction d2 of the pinned layer 30b has a component in the -Y direction and a component in the -Z direction.
In addition, similarly to the magnetoresistive elements Y1B and Y2A shown in FIG. 9, the other magnetoresistive elements Y1D and Y2C to which the external magnetic field H in the other direction (−Y direction) in the first direction is applied are respectively provided. The magnetization is fixed in the in-plane direction of the second inclined surfaces 10c and 10d formed with a component in the −Y direction.

FIG. 10 is a view for explaining the magnetization orientation of the pinned layer of the magnetic sensor according to the first embodiment.
As shown in FIGS. 6 to 9, the magnetization direction of the pinned layer 30b in each of the magnetoresistive effect elements X1A to Y2D that has undergone the above-described ordered heat treatment step is the direction of the external magnetic field H applied by the magnet array 20, and The first inclined surfaces 10a and 10b and the second inclined surfaces 10c and 10d (FIG. 1) are fixed.

  Specifically, the magnetoresistive effect elements X1A, X1C, X2A, and X2C (first magnetoresistive effect elements) arranged in the first region A1 of the partition 1a have a component orthogonal to the + Z direction on the flat surface of the substrate 1W. An external magnetic field H is applied (see FIG. 7). Therefore, after the ordering heat treatment step, as shown in FIG. 10, the magnetoresistive elements X1A and X1C are in-plane directions of the first inclined surface 10a and have + X direction components and + Z direction components. It is fixed in the direction c1. Further, the magnetoresistive effect elements X2A and X2C are fixed in the in-plane direction of the first inclined surface 10b, and the direction c2 having a −X direction component and a + Z direction component.

  On the other hand, the magnetoresistive elements Y1A, Y1C, Y2B, Y2D (second magnetoresistive elements) arranged in the second region A2 of the section 1a are external magnetic fields having a component in the + Y direction parallel to the flat surface of the substrate 1W. H is applied (see FIG. 8). Therefore, after the ordering heat treatment step, as shown in FIG. 10, the magnetoresistive elements Y1A, Y1C are in the in-plane direction of the second inclined surface 10c and have + Y direction component and −Z direction component. The orientation d1 is fixed. In addition, the magnetoresistive elements Y2B and Y2D are fixed in the in-plane direction of the second inclined surface 10d, and the azimuth d4 having a + Y direction component and a + Z direction component.

  Furthermore, the magnetoresistive elements Y1B, Y1D, Y2A, Y2C (second magnetoresistive elements) arranged in the third region A3 of the section 1a are external components having a component in the −Y direction parallel to the flat surface of the substrate 1W. A magnetic field H is applied (see FIG. 9). Therefore, after the ordering heat treatment step, as shown in FIG. 10, the magnetoresistive elements Y1B and Y1D are in-plane directions of the second inclined surface 10c, and have a −Y direction component and a + Z direction component. The orientation d3 is fixed. In addition, the magnetoresistive elements Y2A and Y2C are fixed in the in-plane direction of the second inclined surface 10d, and the azimuth d2 having a −Y direction component and a −Z direction component.

  Thus, in the ordered heat treatment step of the magnetic sensor 1 according to this embodiment, the vertical component (+ Z direction) orthogonal to the flat surface of the substrate 1W and the horizontal component (± Y direction) parallel to the flat surface of the substrate 1W. And applying an external magnetic field H. Based on the perpendicular component, the magnetization direction of the pinned layer 30b corresponding to some of the magnetoresistive elements X1A, X1C, X2A, and X2C among the plurality of magnetoresistive elements X1A to Y2D is fixed. Further, based on the horizontal component, the magnetization of the pinned layer 30b corresponding to the other magnetoresistive elements Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C, Y2D among the plurality of magnetoresistive elements X1A to Y2D. Fix the orientation of.

In the magnetic sensor 1 manufactured through the ordering heat treatment step, the magnetoresistive effect elements X1A, X1C, X2A, and X2C (first magnetoresistive effect elements) arranged in the first region A1 are the magnetization of the pinned layer 30b. The azimuth has a component that faces at least one azimuth (+ Z direction) orthogonal to the flat surface of the substrate 1W.
Further, in the magnetoresistive effect elements Y1A, Y1C, Y2B, Y2D (second magnetoresistive effect elements) arranged in the second region A2, the magnetization direction of the pinned layer 30b is at least one parallel to the flat surface of the substrate 1W. Has a component facing the direction (+ Y direction).
Further, in the magnetoresistive effect elements Y1B, Y1D, Y2A, Y2C (second magnetoresistive effect elements) arranged in the third region A3, the magnetization direction of the pinned layer 30b is at least parallel to the flat surface of the substrate 1W. Has a component facing the direction (−Y direction).

  Although not shown in FIG. 10, the magnetization directions (directions My and Mx described later) of the free layers 30d of the magnetoresistive elements X1A to Y2D are directions along the respective longitudinal directions (FIG. 3). reference).

As described above, in FIGS. 7 to 10, the orientation of the external magnetic field H for each of the first region A1 to the third region A3 in the section 1a and the orientations c1, c2, d1, d2, d3, and d4 of the magnetization of the pinned layer 30b are shown. As described above, the same external magnetic field H as that of the section 1a is applied to the other sections 1b and 1c opposed to the first magnet 20N.
On the other hand, for the sections 1d, 1e, and 1f and the sections 1g, 1h, and 1i facing the second magnet 20S, an external magnetic field H that is opposite to the section 1a is applied. For example, an external magnetic field H directed downward (−Z direction) is applied to the first region A1 in the section 1d. In addition, an external magnetic field H that faces the other direction (−Y direction) in the first orientation is applied to the second region A2 in the section 1d, and one orientation (+ Y direction) in the first orientation is applied to the third region A3. ) Is applied. Accordingly, the magnetization direction of the pinned layer 30b fixed in the section 1d based on the external magnetic field H is opposite to the magnetization direction of the pinned layer 30b in the section 1a (FIGS. 7 to 10).

[Circuit configuration]
FIG. 11 is a diagram illustrating a circuit configuration of the magnetic sensor according to the first embodiment.
Next, a circuit configuration including the magnetoresistive elements X1A to Y2D in the section 1a illustrated in FIG. 10 will be described with reference to FIG.
In the manufacturing process of the magnetic sensor 1 according to the present embodiment, in the wiring forming step performed after the ordering heat treatment process, wirings (for example, the wiring layer 31a shown in FIG. 3) that electrically connects the magnetoresistive elements X1A to Y2D and the like. , 31b, etc.). Specifically, the magnetoresistive elements X1A to Y2D are connected by wiring as shown in FIGS. Here, as shown in FIG. 10, the first inclined surfaces 10a and 10b are formed in the first region A1, and the second inclined surfaces 10c and 10d are formed in both the second region A2 and the third region A3. Has been. In the wiring formation step, a bridge circuit (FIG. 11 (a)) including four magnetoresistive elements X1A, X1C, X2A, and X2C belonging to the first region A1, the second region A2, and the third region Among the magnetoresistive elements Y1A to Y2D belonging to A3, a bridge circuit (FIGS. 11B and 11C) is formed by combining elements having the same inclined surface (second inclined surfaces 10c and 10d). .

As shown in FIG. 11A, in the bridge circuit BX1, the magnetoresistive effect element X1A and the magnetoresistive effect element X2A are connected in series between the power supply terminal Q1 and the ground terminal Q2. At this time, one end of the magnetoresistive effect element X1A is connected to the power supply terminal Q1, and one end of the magnetoresistive effect element X2A is connected to the ground terminal Q2. Similarly, the magnetoresistive effect element X2C and the magnetoresistive effect element X1C are connected in series between the power supply terminal Q1 and the ground terminal Q2. At this time, one end of the magnetoresistive effect element X2C is connected to the power supply terminal Q1, and one end of the magnetoresistive effect element X1C is connected to the ground terminal Q2. Here, a positive terminal and a negative terminal of a constant voltage source (not shown) are connected to the power supply terminal Q1 and the ground terminal Q2, respectively, a power supply voltage Vin + (for example, 3V) is applied to the power supply terminal Q1, and a ground voltage is applied to the ground terminal Q2. Vin− (for example, 0V) is applied.
Further, as shown in FIG. 11A, the bridge circuit BX1 includes a potential between the magnetoresistive effect element X1A and the magnetoresistive effect element X2A, and between the magnetoresistive effect element X1C and the magnetoresistive effect element X2C. An output voltage Vx1 which is a potential difference between the potential and the potential is output.

The magnetization direction c1 of the pinned layer 30b (FIG. 3) of the magnetoresistive effect elements X1A and X1C and the magnetization direction c2 of the pinned layer 30b of the magnetoresistive effect elements X2A and X2C are horizontal components (± X direction components). Are opposite to each other. On the other hand, the orientation of the magnetization Mx of the free layer 30d (FIG. 3) of each of the magnetoresistive effect elements X1A to X2C can be changed in the in-plane directions of the first inclined surfaces 10a and 10b. The orientation changes based on the component Hx in the ± X direction of the external magnetic field.
Then, for example, when the component Hx of the external magnetic field to be measured is in the + X direction, the orientation of the magnetization Mx of the free layer 30d is inclined to the + X direction side, so that the resistance values of the magnetoresistive effect elements X1A and X1C decrease. The resistance values of the magnetoresistive effect elements X2A and X2C increase. As a result, the output voltage Vx1 changes to the plus side according to the component Hx of the external magnetic field in the + X direction. On the other hand, when the component Hx of the external magnetic field to be measured is in the −X direction, the orientation of the magnetization Mx of the free layer 30d is inclined to the −X direction side, so that the resistance values of the magnetoresistive effect elements X1A and X1C increase. The resistance values of the magnetoresistive effect elements X2A and X2C decrease. As a result, the output voltage Vx1 changes to the minus side in accordance with the external magnetic field component Hx in the -X direction.

The magnetization direction c1 of the pinned layer 30b (FIG. 3) of each magnetoresistive element X1A, X1C and the magnetization direction c2 of the pinned layer 30b of the magnetoresistive effect elements X2A, X2C are perpendicular components (± Z direction). The direction of (component) is the same as the + Z direction. On the other hand, the orientation of the magnetization Mx of the free layer 30d (FIG. 3) of each of the magnetoresistive effect elements X1A to X2C can be changed in the in-plane directions of the first inclined surfaces 10a and 10b. The direction changes based on the component Hz in the ± Z direction of the external magnetic field.
Then, for example, when the component Hz of the external magnetic field to be measured is in the + Z direction, the direction of the magnetization Mx of the free layer 30d is inclined to the + Z direction side, so that the resistance of the magnetoresistive effect elements X1A, X1C, X2A, X2C All values decrease. Thus, the output voltage Vx1 does not change depending on the component Hz of the external magnetic field in the + Z direction. On the other hand, when the component Hz of the external magnetic field to be measured is in the −Z direction, the direction of the magnetization Mx of the free layer 30d is inclined toward the −Z direction, so that the resistance of the magnetoresistive effect elements X1A, X1C, X2A, and X2C All values increase. As a result, the output voltage Vx1 is not changed by the component Hz of the external magnetic field in the -Z direction.
As described above, the bridge circuit BX1 functions as a magnetic sensor having a sensitivity direction only in the second direction (± X direction) of the horizontal component of the external magnetic field to be measured.

The magnetic sensor 1 can calculate the component Hx in the ± X direction of the applied external magnetic field from the output voltage Vx1 of the bridge circuit BX1. Specifically, the component Hx in the ± X direction of the external magnetic field can be obtained by the following equation (1).
Hx = kx · Vx1 (1)
Here, the sensitivity coefficient kx is a proportional constant of the component X in the ± X direction of the external magnetic field (magnetic field strength in the ± X direction) with respect to the output voltage Vx1.

Further, as shown in FIG. 11B, in the bridge circuit BY1, the magnetoresistive effect element Y1A belonging to the second region A2 and the magnetoresistive effect element Y1B belonging to the third region A3 are connected to the power supply terminal Q1 and the ground terminal Q2. Connected in series. At this time, one end of the magnetoresistive effect element Y1A is connected to the power supply terminal Q1, and one end of the magnetoresistive effect element Y1B is connected to the ground terminal Q2. Similarly, the magnetoresistive element Y1D belonging to the third area A3 and the magnetoresistive element Y1C belonging to the second area A2 are connected in series between the power supply terminal Q1 and the ground terminal Q2. At this time, one end of the magnetoresistive effect element Y1D is connected to the power supply terminal Q1, and one end of the magnetoresistive effect element Y1C is connected to the ground terminal Q2.
As shown in FIG. 11B, the bridge circuit BY1 includes a potential between the magnetoresistive effect element Y1A and the magnetoresistive effect element Y1B, and between the magnetoresistive effect element Y1D and the magnetoresistive effect element Y1C. An output voltage Vy1 which is a potential difference between the potential and the potential is output.

  The magnetization directions d1 and d3 of the pinned layer 30b (FIG. 3) of the magnetoresistive elements Y1A to Y1D are fixed in the in-plane direction of the second inclined surface 10c and opposite to each other. Further, the orientation of the magnetization My1 of the free layer 30d (FIG. 3) of each of the magnetoresistive elements Y1A to Y1D changes in the in-plane direction of the second inclined surface 10c according to the applied external magnetic field. That is, the bridge circuit BY1 changes the output voltage Vy1 according to the combined component of the + Y direction and the −Z direction in the applied external magnetic field.

Similarly, as shown in FIG. 11C, in the bridge circuit BY2, the magnetoresistive effect element Y2A belonging to the third region A3 and the magnetoresistive effect element Y2B belonging to the second region A2 are connected to the power supply terminal Q1 and the ground terminal. Connected in series with Q2. At this time, one end of the magnetoresistive effect element Y2A is connected to the power supply terminal Q1, and one end of the magnetoresistive effect element Y2B is connected to the ground terminal Q2. Similarly, the magnetoresistive element Y2D belonging to the second region A2 and the magnetoresistive element Y2C belonging to the third region A3 are connected in series between the power supply terminal Q1 and the ground terminal Q2. At this time, one end of the magnetoresistive element Y2D is connected to the power supply terminal Q1, and one end of the magnetoresistive element Y2C is connected to the ground terminal Q2.
As shown in FIG. 11C, the bridge circuit BY2 includes a potential between the magnetoresistive effect element Y2A and the magnetoresistive effect element Y2B, and between the magnetoresistive effect element Y2D and the magnetoresistive effect element Y2C. An output voltage Vy2 which is a potential difference between the potential and the potential is output.

  The magnetization directions d2 and d4 of the pinned layer 30b (FIG. 3) of the magnetoresistive elements Y2A to Y2D are fixed in the in-plane direction of the second inclined surface 10d and opposite to each other. Further, the orientation of the magnetization My2 of the free layer 30d (FIG. 3) of each of the magnetoresistive elements Y2A to Y2D changes in the in-plane direction of the second inclined surface 10d according to the applied external magnetic field. That is, the bridge circuit BY2 changes the output voltage Vy2 according to the combined component of the + Y direction and the + Z direction in the applied external magnetic field.

The magnetic sensor 1 combines the output voltage Vy1 of the bridge circuit BY1 and the output voltage Vy2 of the bridge circuit BY2 to separately calculate the ± Y direction component and the ± Z direction component of the applied external magnetic field. Can do. Specifically, the ± Y direction component Hy of the external magnetic field can be obtained by the following equation (2).
Hy = ky (Vy1-Vy2) (2)
Here, the sensitivity coefficient ky is a proportional constant of the component Hy (magnetic field strength in the ± Y direction) of the external magnetic field with respect to the output voltages Vy1 and Vy2.

Further, the component Hz in the ± Z direction of the external magnetic field can be obtained by the following equation (3).
Hz = kz (Vy1 + Vy2) (3)
Here, the sensitivity coefficient kz is a proportionality constant of the component Hz (magnetic field strength in the ± Z direction) of the external magnetic field with respect to the output voltages Vy1 and Vy2.

The magnetic sensor 1 separately includes a magnetic field intensity calculation unit that inputs the output voltages Vx1, Vy1, and Vy2 of the bridge circuits BX1, BY1, and BY2, and calculates each direction component (Hx, Hy, Hz) of the external magnetic field. I have. In this case, for example, the magnetic field intensity calculation unit inputs the output voltage Vx1 through the A / D conversion circuit and executes the step of acquiring the sampling value SVx1, and then similarly through the A / D conversion circuit. The step of acquiring the sampling values SVy1 and SVy2 by sequentially inputting the output voltages Vy1 and Vy2 may be executed. Thereafter, the magnetic field intensity calculation unit calculates the directional components (Hx, Hy, Hz) of the external magnetic field by performing the calculations of Expressions (1) to (3) based on the acquired sampling values SVx1, SVy1, SVy2. .
In this case, each bridge circuit BX1, BY1, BY2 is output to the magnetic field intensity calculation unit (A / D conversion circuit) via an amplifier (output amplifier) that amplifies each output voltage Vx1, Vy1, Vy2. Good.

  Note that the bridge circuits BX1, BY1, and BY2 illustrated in FIGS. 11A to 11C are configured using the magnetoresistive effect elements X1A to Y2D in the section 1a. In another section (for example, section 1d) in which the magnetization direction of the pinned layer 30b is fixed in the opposite direction with respect to the section 1a, output voltages Vx1, Vy1, output from the bridge circuits BX1, BY1, BY2 respectively. The polarities of changes in Vy2 with respect to the external magnetic field are all reversed. Therefore, the magnetic field intensity calculation unit arranged in the section 1d and the like calculates the magnetic field intensity for each component Hx, Hy, Hz with sensitivity coefficients kx, ky, kz having the opposite polarity to the section 1a. The magnetic sensor is equivalent to the magnetic sensor 1 having the section 1a as the main body.

[Function and effect]
FIG. 12 is a first diagram illustrating a method for manufacturing a magnetic sensor according to the comparison of the first embodiment. FIG. 13 is a second view for explaining the magnetic sensor manufacturing method according to the first embodiment.
Next, the effect of the manufacturing method of the magnetic sensor 1 mentioned above is demonstrated, comparing with the comparison shown to FIG. 12, FIG.

As shown in FIG. 12, the magnetic sensor 9 (FIG. 13) according to the comparison of the first embodiment is formed for each section (section 1a ′) arranged on the flat surface of the substrate 1W.
Here, also in the ordered heat treatment step according to the comparison, similarly to the ordered heat treatment step according to the first embodiment, a substrate 1W on which a multilayer film such as a pinned layer 30b is formed is prepared with a magnet prepared in advance. A predetermined heat treatment is performed on the array 20 (see FIG. 4).

  As shown in FIG. 12, the magnet array 20 ′ according to the comparison includes a first magnet 20N ′ that makes the N-pole surface (one polarity surface) face the substrate 1W, and an S-pole surface (to the substrate 1W). The second magnets 20S ′ facing the other polar surfaces) are alternately arranged in a matrix. However, unlike the first embodiment, the first magnet 20N ′ and the second magnet 20S ′ are arranged in a one-to-one correspondence with each section (section 1a ′, etc.) on the flat surface of the substrate 1W. Yes.

  Specifically, as shown in FIG. 12, the center of the polar surface of the first magnet 20N ′ facing the N-pole surface overlaps the center of the section 1a ′, which is one section of the flat surface of the substrate 1W. Is arranged. Similarly, the polar surface of the second magnet 20 </ b> S ′ facing the surface of the south pole is arranged so that the center thereof overlaps the center of another section adjacent to the section 1 a ′. Accordingly, in this case, the external magnetic field H ′ generated by the magnet array 20 ′ is emitted from the polar surface of the first magnet 20N ′, and the four second magnets 20S ′ arranged in the ± X and ± Y directions thereof. Head to each of the polar planes.

Here, FIG. 13 shows the structure of the magnetic sensor 9 according to the proportionality and the magnetization direction of the pinned layer 30b (not shown in FIG. 13) of each of the magnetoresistive elements X1A to Y2D.
As shown in FIG. 13, the magnetic sensor 9 includes twelve magnetoresistive elements X1A, X1C, X2A, X2C, Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C in a rectangular plate-shaped section 1a ′. Y2D.
Of the twelve magnetoresistive elements X1A to Y2D, the magnetoresistive elements X1A, X1C, X2A, and X2C are formed on the flat surface of the substrate 1W so that the ± Y direction is the longitudinal direction. The magnetoresistive elements Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C, and Y2D are all formed on inclined surfaces (second inclined surfaces 10c and 10d) that are inclined with respect to the flat surface of the substrate 1W. Yes.

  Specifically, the magnetoresistive elements Y1A, Y1B, Y1C, and Y1D are formed on the second inclined surface 10c that is inclined so as to descend from the −Y direction side to the + Y direction side (go to the −Z direction side). The On the other hand, the magnetoresistive elements Y2A, Y2B, Y2C, and Y2D are formed on the second inclined surface 10d that is inclined so as to rise from the −Y direction side to the + Y direction side (go to the + Z direction side).

  As shown in FIG. 13, the magnetoresistive elements X2A and X2C are arranged near the center of the side on the −X direction side of the section 1a ′, and the magnetoresistive elements X1A and X1C are in the + X direction of the section 1a ′. Arranged near the center of the side. Further, the magnetoresistive elements Y1A, Y1C, Y2B, Y2D are arranged near the center of the side on the + Y direction side of the section 1a ′, and the magnetoresistive elements Y1B, Y1D, Y2A, Y2C are −Y of the section 1a ′. Arranged near the center of the direction side.

  The magnetization direction of the pinned layer 30b in each of the magnetoresistive effect elements X1A to Y2D that has undergone the ordered heat treatment step is the horizontal component of the external magnetic field H ′ (FIG. 12) applied by the magnet array 20 (the surface of the flat surface of the substrate 1W). It is fixed based on the direction of the inward component.

  Specifically, the magnetization direction of the pinned layer 30b of the magnetoresistive elements X2A and X2C arranged near the center of the −X direction side of the section 1a ′ is the external magnetic field H ′ in the −X direction (FIG. 12). ), The orientation c2 ′ having only the component in the −X direction is fixed. Further, the magnetization direction of the pinned layer 30b of the magnetoresistive effect elements X1A and X1C arranged near the center of the side on the + X direction side of the section 1a ′ is set in the + X direction by the external magnetic field H ′ (FIG. 12) in the + X direction. It is fixed to the orientation c1 ′ having only the component.

Similarly, the magnetoresistive elements Y1A and Y1C are in-plane directions of the second inclined surface 10c and have an + Y direction component and a −Z direction component due to the external magnetic field H ′ (FIG. 12) in the + Y direction. It is fixed to d1. The magnetoresistive elements Y2B and Y2D are fixed in the in-plane direction of the second inclined surface 10d by the external magnetic field H ′ in the + Y direction and in the direction d4 having the + Y direction component and the + Z direction component.
Further, the magnetoresistive effect elements Y1B and Y1D are in-plane directions of the second inclined surface 10c by the external magnetic field H ′ (FIG. 12) in the −Y direction, and have an −Y direction component and a + Z direction component. It is fixed to d3. In addition, the magnetoresistive elements Y2A and Y2C are fixed in the in-plane direction of the second inclined surface 10d by the external magnetic field H ′ in the −Y direction, and the orientation d2 having the −Y direction component and the −Z direction component. Is done.

Of the twelve magnetoresistive effect elements X1A to Y2D of the magnetic sensor 9 according to the comparative example, a set of the magnetoresistive effect elements X1A, X1C, X2A, and X2C is connected to form a bridge circuit. Similarly, the set of magnetoresistive elements Y1A, Y1B, Y1C, and Y1D and the set of magnetoresistive elements Y2A, Y2B, Y2C, and Y2D are similarly wire-connected to form a bridge circuit (FIG. 11).
The magnetic sensor 9 according to the comparison is a three-axis magnetic sensor that can measure by three components (Hx, Hy, Hz) orthogonal to each other with the above configuration.

  Next, the effect of the magnetic sensor 1 according to the first embodiment will be described while comparing the magnetic sensor 1 according to the first embodiment with the magnetic sensor 9 according to the comparison.

  First, in the ordering heat treatment process of the magnetic sensor 1 according to the first embodiment, based on the vertical component of the external magnetic field H having a vertical component and a horizontal component with respect to the substrate 1W, the plurality of magnetoresistive effect elements X1A to Y2D Among them, the magnetization direction of the pinned layer 30b corresponding to some of the magnetoresistive effect elements X1A, X1C, X2A, and X2C is fixed.

Moreover, in the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, the other of the plurality of magnetoresistive elements X1A to Y2D based on the horizontal component of the external magnetic field H having a vertical component and a horizontal component. The magnetization direction of the pinned layer 30b corresponding to the magnetoresistive elements Y1A to Y2D is fixed.
By doing in this way, it respond | corresponds to each of several magnetoresistive effect element X1A-Y2D based on each of the perpendicular | vertical component orthogonal to the flat surface of the board | substrate 1W, and the horizontal component parallel to the flat surface of the board | substrate 1W. Since the magnetization direction of the pinned layer 30b is fixed, the magnetization of the pinned layer 30b can be fixed in a plurality of different directions. Therefore, since a plurality of magnetoresistive effect elements having different sensitivity directions can be formed, the external magnetic field to be measured can be measured for each component in a plurality of different directions.

Moreover, according to the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, the pinned layer in the first region A1 disposed in the center among the three regions in which the partition 1a is partitioned by parallel straight lines. The magnetization direction of 30b is fixed based on the vertical component of the external magnetic field. In the second region A2 and the third region A3 arranged on both sides of the first region A1 of the partition 1a, the magnetization direction of the pinned layer 30b is fixed based on the horizontal component of the external magnetic field. Here, the azimuth of the horizontal component applied to the second area A2 and the azimuth of the horizontal component applied to the third area A3 are opposite to each other.
By doing in this way, in the 2nd field A2 and the 3rd field A3 in one division, the pinned layer whose direction of magnetization is opposite to each other can be formed. Therefore, a magnetic sensor with high detection accuracy can be manufactured by combining a magnetoresistive effect element having pinned layers whose magnetization directions are opposite to each other to form a bridge circuit.
Moreover, by doing in this way, only one polar surface of a single magnet is made to oppose one division, and it is from 1st area | region A1 to 3rd area | region A3 by the external magnetic field which arises radially from the said polar face. An external magnetic field having a desired orientation can be applied to all of the above. Therefore, the number of the polar surfaces of the magnet opposed to one section can be made one, and the alignment accuracy of the polar surface with respect to each section can be improved.

  Further, in the case of the regularized heat treatment of the magnetic sensor 9 according to the proportionality, the first magnet 20N and the second magnet 20S formed in a minute rectangular shape are divided on the semiconductor wafer (substrate 1W) (section 1a ′ and the like). (See FIG. 12). On the other hand, according to the ordered heat treatment step of the magnetic sensor 1 according to the first embodiment, a plurality of sections (for example, for example) arranged in one direction (second direction) on the flat surface of the substrate 1W. An external magnetic field is applied to each of the compartments 1a, 1b, and 1c) using a bar magnet (first magnet 20N or second magnet 20S) extending in the one direction. By doing in this way, it is possible to apply an external magnetic field to each of a plurality of sections arranged side by side in the one direction by using a bar magnet extending in the one direction. It is not necessary to arrange a magnet so as to correspond to a plurality of sections. Therefore, the burden in the regularized heat treatment process can be reduced.

Further, in the case of the regularized heat treatment of the magnetic sensor 9 according to the proportionality, it is necessary to process the first magnet 20N and the second magnet 20S minutely, so that variations in shape and size are likely to occur. In addition, since the number of minutely processed first magnets 20N and second magnets 20S to be arranged on the magnet array 20 is increased, variations in arrangement positions are likely to occur. Thus, if there is variation in the shape, size, or arrangement position of the first magnet 20N and the second magnet 20S, the direction of the external magnetic field applied for each section also varies, and therefore, based on the external magnetic field. The variation in sensor characteristics of the magnetic sensor 9 manufactured in this way also increases.
On the other hand, according to the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, by arranging the bar magnets (first magnet 20N, second magnet 20S) formed in a bar shape in parallel with each other, As the shapes of the first magnet 20N and the second magnet 20S increase in size, the number to be arranged decreases. Therefore, variation in the shape and size of the first magnet 20N and the second magnet 20S and the arrangement position can be reduced.

Moreover, by doing in this way, it arrange | positions so that a bar magnet (the 1st magnet 20N or the 2nd magnet 20S) may extend in parallel with the azimuth | direction which arrange | positions and arrange | positions a division (section 1a, 1b, 1c etc.). Therefore, a uniform external magnetic field that goes straight in the direction (± Y direction) perpendicular to the extending direction (± X direction) of the bar magnet is applied over the entire range of the section. Therefore, it is possible to eliminate a component that curves in an arc on the flat surface of the substrate from the external magnetic field applied by the bar magnet. Therefore, the magnetization direction of the pinned layer 30b arranged in the second region A2 and the third region A3 can be accurately fixed to a desired direction based on the horizontal component of the external magnetic field.
As described above, the magnetic sensor 1 according to the first embodiment can significantly reduce variations in sensor characteristics as compared with the magnetic sensor 9 according to the comparative example.

Moreover, according to the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, the first magnet 20N and the second magnet 20S are formed in the first region in each of a plurality of sections (sections 1a, 1b, 1c, etc.). It extends while facing A1.
By doing in this way, the pinned layer 30b which belongs to each 1st area | region A1 of division 1a etc. is distribute | arranged to the position facing the polar surface of the 1st magnet 20N and the 2nd magnet 20S. Thereby, an external magnetic field H having a strong vertical component that is a magnetic field generated in the normal direction (± Z direction) of the polar surfaces of the first magnet 20N and the second magnet 20S is applied to the pinned layer 30b. it can. Therefore, based on the vertical component of the external magnetic field H, the magnetization direction of the pinned layer 30b can be accurately fixed to a desired direction.

Furthermore, in the first embodiment, as described above, the first magnet 20N and the second magnet 20S include the center position O1 in the longitudinal direction of the magnetoresistive elements X1A, X1C, X2A, and X2C and the first magnet 20N. And the center position O2 in the width direction of the polar plane is aligned in the first direction (± Y direction) (see FIG. 5).
By doing so, a vertical external magnetic field H having only a vertical component (± Z direction) is applied to the magnetoresistive elements X1A, X1C, X2A, and X2C arranged in the first region A1. Therefore, the magnetization direction of the pinned layer 30b can be more accurately fixed to the desired direction.

Moreover, according to the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, the first magnet 20N that makes the N pole polar face face the first region A1 in one section (for example, the section 1a). And the second magnet 20S that makes the polar face of the S pole face the first region A1 in the other section (for example, the section 1d) adjacent to the one section on the same plane, Applied.
By doing in this way, the pinned layer 30b belonging to each of the second region A2 and the third region A3 of each of the plurality of sections has the first polar surface facing the N pole in the in-plane direction of the flat surface of the substrate 1W. It is arranged near the center between the magnet 20N and the second magnet 20S facing the polar face of the south pole (see FIG. 6). Thereby, an external magnetic field H having a strong horizontal component, which is a magnetic field generated between the N-polarity plane of the first magnet 20N and the S-polarity plane of the second magnet 20S, is applied to the pinned layer 30b. be able to. Therefore, the magnetization direction of the pinned layer 30b belonging to the first region A1 is fixed as desired based on the vertical component of the external magnetic field H, while the second region A2 and the third region A3 are based on the horizontal component of the external magnetic field H. It is possible to accurately fix the magnetization direction of the pinned layer 30b to the desired direction.
Moreover, by doing in this way, the magnet array 20 which is a jig | tool arranged on the same plane so that the 1st magnet 20N and the 2nd magnet 20S may align with each division (compartment 1a etc.) is piled up on the board | substrate 1W. Thus, since the external magnetic field H having a component orthogonal to the flat surface and a component parallel to the flat surface can be applied, the work of the ordered heat treatment process can be simplified.

Furthermore, in the film forming step of the magnetic sensor 1 according to the first embodiment, the pinned layer 30b contacts the flat surface along the first direction (± Y direction) in the in-plane direction of the flat surface of the substrate 1W. First inclined surfaces 10a and 10b provided in this manner and second inclined surfaces 10c and 10d provided so as to be in contact with the flat surface along a second orientation (± X direction) different from the first orientation. Films are formed on both.
Thus, in the magnetic sensor 1, a plurality of magnetoresistive elements having different sensitivity directions (directions in which the intensity of the external magnetic field can be mainly observed) are formed in the in-plane direction of the flat surface. It becomes possible to measure for each component of the direction.

The magnetic sensor 1 according to the first embodiment is a magnetoresistive effect element including a multilayer body including a rectangular plate-shaped main body (section 1a) and a pinned layer 30b, and the first direction is a longitudinal direction. Magnetoresistive effect elements X1A, X1C, X2A, X2C (first magnetoresistive effect elements) and magnetoresistive effect elements Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C, Y2D (with the second direction as the longitudinal direction) 2nd magnetoresistive effect element). And in the 1st field A1 arranged in the center among three fields where the flat surface of division 1a is divided by the straight line parallel to the one side of the division 1a, the 1st magnetoresistive element is arranged, In each of the second region A2 and the third region A3 disposed on both sides of the first region A1, the second magnetoresistance effect element is disposed.
By doing in this way, in the manufacturing process of the magnetic sensor 1, when a plurality of rectangular plate-like main body portions are arranged in one orientation of one flat surface of the substrate 1W as a single section, on the flat surface of the substrate The first region A1 to the third region A3 can be connected to the one direction and arranged in a row. Accordingly, the first magnetoresistive element and the second magnetoresistive element are applied to each of the first region A1 to the third region A3 while collectively applying an external magnetic field using the bar magnet extending in the one direction. Since the orientation of the magnetization of the pinned layer in can be fixed, the work load in the manufacturing process of the magnetic sensor 1 can be reduced.
Moreover, by doing in this way, it respond | corresponds to each of several magnetoresistive effect element X1A-Y2D based on each of the vertical component orthogonal to the flat surface of the board | substrate 1W, and the horizontal component parallel to the flat surface of the board | substrate 1W. Since the magnetization direction of the pinned layer 30b is fixed, the magnetization of the pinned layer 30b can be fixed in a plurality of different directions.

In the magnetic sensor 1 according to the first embodiment, the magnetization direction of the pinned layer 30b in the first magnetoresistive element arranged in the first region A1 is at least one direction orthogonal to the flat surface of the substrate 1W. It has a component facing. Further, the magnetic sensor 1 is a component in which the magnetization direction of the pinned layer 30b in the second magnetoresistive effect element arranged in the second region A2 is directed to at least one direction (+ Y direction) parallel to the flat surface of the substrate 1W. have. Further, in the magnetic sensor 1, the magnetization direction of the pinned layer 30b in the second magnetoresistive element arranged in the third region A3 is directed to at least another direction (−Y direction) parallel to the flat surface of the substrate 1W. Has ingredients.
By doing so, a bridge circuit can be configured by combining magnetoresistive elements having pinned layers whose magnetization directions are opposite to each other in one section, so that a magnetic sensor with high detection accuracy can be manufactured. . In addition, since a plurality of magnetoresistive elements having different sensitivity directions can be formed, the external magnetic field to be measured can be measured for each component in a plurality of different directions.

FIG. 14 is a diagram for explaining the effect of the magnetic sensor manufacturing method according to the first embodiment.
The magnetic sensor 1 according to the first embodiment is arranged at the center of the region formed by dividing the flat surface of the section 1a into three with straight lines parallel to one side of the section 1a in the regularization heat treatment step. The polar face of the first magnet 20N extending in parallel with the one side faces the one region A1 (see FIG. 5).

In this case, a uniform external portion having components in directions (± Y direction, ± Z direction) orthogonal to the extending direction over the entire range of the section 1a in the extending direction (± X direction) of the first magnet 20N. A magnetic field H is applied. Then, the same external magnetic field H is always applied to the magnetoresistive elements X1A to Y2D regardless of the position of the section 1a in the extending direction of the first magnet 20N. That is, according to the ordered heat treatment process according to the first embodiment, the degree of freedom of the arrangement position of the magnetoresistive effect elements X1A to Y2D in the extending direction of the first magnet 20N is increased. Thereby, the magnetic sensor 1 can arrange | position the circuit required in order to implement | achieve the function of the said magnetic sensor 1 efficiently, and can attain reduction of the size of a main-body part (section 1a).
For example, according to the ordered heat treatment process according to the first embodiment, as shown in FIG. 14, all twelve magnetoresistive elements X1A to Y2D are connected to one side in the extending direction of the first magnet 20N (− It is also possible to collect and arrange them on the X direction side). In this way, two different analog circuits including the magnetoresistive elements X1A to Y2D (output amplifier, noise removal filter, etc.) and a logic circuit that performs digital processing on the sampling value indicating the strength of the magnetic field are different. It can be arranged in one area. That is, according to the magnetic sensor 1 as shown in FIG. 14, various analog circuits including the magnetoresistive effect elements X1A to Y2D have the section 1a in the direction (± Y direction) perpendicular to the extending direction of the first magnet 20N. It is collected on one side (analog circuit area BA) of the divided area. Further, according to the magnetic sensor 1, the logic circuit that performs the digital processing is an area in which the section 1a is divided into directions (± Y directions) orthogonal to the extending directions of the first magnet 20N and the second magnet 20S. It is collected on the other side (logic circuit area BD).
For example, in the first embodiment, the analog circuit area BA and the logic circuit area BD include a flat surface of the partition 1a and a boundary line that partitions each of the first region A1, the second region A2, and the third region A3. It is divided into two equal parts along an orthogonal straight line. In this case, the magnetoresistive effect elements X1A to Y2D are arranged only on one side of two regions obtained by dividing the flat surface of the section 1a into two equal parts.
In other embodiments, the way of dividing the analog circuit area BA and the logic circuit area BD on the flat surface of the partition 1a is not limited to the above-described mode.

  As described above, according to the magnetic sensor and the method of manufacturing the magnetic sensor according to the first embodiment, it is possible to reduce the burden in the step of fixing the magnetization direction of the pinned layer.

<Other variations>
In addition, the manufacturing method of the magnetic sensor 1 according to the first embodiment is not limited to the above-described aspect, and can be modified as follows as an example.

FIG. 15 is a diagram for explaining the outline of the ordered heat treatment process according to the modification of the first embodiment.
In the regularization heat treatment process of the magnetic sensor 1 according to the first embodiment, the magnet array 20 has been described as being disposed so as to overlap one side (back side) of the substrate 1W (see FIG. 4). However, in the ordered heat treatment process according to another embodiment, for example, as shown in FIG. 15A, another magnet array 40 is also arranged on the other side (surface side) of the substrate 1W. Also good. At this time, each permanent magnet (first magnet 20N, second magnet 20S) constituting the magnet array 20 and each permanent magnet (first magnet 40N, second magnet 40S) constituting the magnet array 40 are respectively It is assumed that the opposing polar surfaces have different polarities (see FIG. 15A).
As a result, among the directional components of the external magnetic field H, the component orthogonal to the flat surface is stronger than the other directional components, and therefore the magnetization orientation of the pinned layer 30b (FIG. 3) fixed in the first region A1. Accuracy can be increased.

  Note that the same effect as in the case of FIG. 15A can also be obtained by arranging the yoke 50 shown in FIG. 15B instead of the magnet array 40. Here, the yoke 50 is made of a soft magnetic material such as iron, for example. Specifically, the yoke 50, which is a soft magnetic material, faces each of the first magnet 20N and the second magnet 20S of the magnet array 20, so that the facing portions have a polarity opposite to the facing polarity. Change. Thereby, the substrate 1W is substantially equivalent to a state of being sandwiched between the magnet array 20 and the magnet array 40 as shown in FIG. Therefore, the external magnetic field H mainly composed of a component orthogonal to the flat surface of the substrate 1W can be applied, and the accuracy of the magnetization orientation of the pinned layer 30b (FIG. 3) fixed in the first region A1 can be improved. it can.

  As described above, by arranging the magnetic body so as to sandwich each of the first magnet 20N and the second magnet 20S of the magnet array 20 and the flat surface of the substrate 1W, components other than components orthogonal to the flat surface of the substrate 1W can be obtained. An external magnetic field in which other direction components are excluded can be applied. Therefore, it is possible to further improve the accuracy of the magnetization orientation of the pinned layer 30b (FIG. 3) fixed in the first region A1.

  Further, the arrangement of the magnet array 20 shown in FIG. 5 is an example and is not limited to this. The first magnet 20N and the second magnet 20S are flat with respect to the pinned layer 30b formed on the flat surface. Any arrangement may be employed as long as an external magnetic field having a vertical component orthogonal to the surface and a horizontal component parallel to the flat surface can be applied. However, in this case, the pinned layer 30b disposed in the first region A1 is disposed to be inclined with respect to the flat surface so that the magnetization direction is fixed based on the vertical component.

In the first embodiment, the bridge circuit is configured by combining magnetoresistive elements having different magnetization directions. However, in the magnetic sensor according to another embodiment, the bridge circuit is not necessarily configured. Not necessary. For example, a bridge circuit may be configured by replacing a part of the four sets of magnetoresistive elements constituting the bridge circuits BX1, BY1, and BY2 (FIG. 11) with resistance elements having known resistance values.
By doing in this way, since the number of the magnetoresistive effect elements which comprise the magnetic sensor 1 can be reduced, the further size reduction of the magnetic sensor 1 can be achieved.

  Further, the phrase “the first magnet 20N faces one polar surface (N-polar surface) with respect to the first region A1” means that the one polar surface faces the magnetoresistive effect elements X1A to Y2D of the substrate 1W. Both the case where it is made to oppose from the flat surface side in which this is formed, and the case where it opposes from the back surface side different from the said flat surface of the board | substrate 1W are included. The same applies to the phrase “the second magnet 20 </ b> S makes the other polar surface (the surface of the S pole) face the first region A <b> 1”.

  The magnetic field intensity calculation unit according to the first embodiment records a program for realizing the function on a computer-readable recording medium, and causes the computer system to read the program recorded on the recording medium, It may be an aspect realized by executing. The “computer system” here includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. In addition, a volatile memory (RAM) that holds a program for a certain period of time is also included.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

  DESCRIPTION OF SYMBOLS 1 ... Magnetic sensor, 1W ... Board | substrate, 1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i ... Division (main-body part), 10 ... Groove part, 10a, 10b ... 1st inclined surface, 10c, 10d ... Second inclined surface 20, 20 ', 40 ... Magnet array, 20N, 20N', 40N ... First magnet, 20S, 20S ', 40S ... Second magnet, 30a ... Pinning layer, 30b ... Pinned layer, 30c ... Spacer Layer, 30d ... free layer, 31a, 31b ... wiring layer, 50 ... yoke, X1A, X1C, X2A, X2C, Y1A, Y1B, Y1C, Y1D, Y2A, Y2B, Y2C, Y2D ... magnetoresistive effect element, BX1, BY1 , BY2 ... bridge circuit, 9 ... magnetic sensor, A1 ... first region, A2 ... second region, A3 ... third region

Claims (9)

A film forming step of forming a multilayer film including at least a pinned layer on the inclined surface provided on the flat surface of the substrate by forming a plurality of magnetoresistive elements;
Applying an external magnetic field having a vertical component perpendicular to the flat surface of the substrate and a horizontal component parallel to the flat surface of the substrate, and based on the vertical component, at least one of the plurality of magnetoresistive elements. The magnetization direction of the pinned layer corresponding to the magnetoresistive effect element of the portion is fixed, and other magnetoresistive elements different from the some magnetoresistive effect elements among the plurality of magnetoresistive effect elements based on the horizontal component A magnetization step for fixing the magnetization direction of the pinned layer corresponding to the effect element;
The manufacturing method of the magnetic sensor which has. In the film forming step,
The multilayer film is formed on an inclined surface provided for each of a plurality of sections arranged side by side on the flat surface of the substrate,
In the magnetizing step,
In the first region arranged in the center among the three regions divided by parallel straight lines, the magnetization direction of the pinned layer is fixed based on the vertical component, and the first region of the partition In the second region and the third region disposed on both sides of the pinned layer, the magnetization direction of the pinned layer is fixed based on the horizontal component,
2. The magnetic sensor according to claim 1, wherein an orientation of the horizontal component applied to the second region and an orientation of the horizontal component applied to the third region are opposite to each other. Production method. In the magnetizing step,
The external magnetic field is applied to each of the plurality of sections arranged in one direction on the flat surface of the substrate using a bar magnet extending in the one direction. A method for manufacturing the magnetic sensor according to claim 2. In the magnetizing step,
The magnetic sensor according to claim 3, wherein the bar magnet extends in the one direction with a polar surface of the bar magnet facing the first region in each of the plurality of sections. Production method. In the magnetizing step,
The first magnet in the bar magnet, the first area in one section facing one polar face, and the first area in the other section adjacent to the one section, the bar magnet. 5. The method of manufacturing a magnetic sensor according to claim 3, wherein the second magnetic field is arranged on the same plane and the external magnetic field is applied to the second magnet facing the other polar surface. In the film forming step,
The pinned layer includes a first inclined surface provided in contact with the flat surface along a first orientation in an in-plane direction of the flat surface, and the flat surface along a second orientation different from the first orientation. 6. The method of manufacturing a magnetic sensor according to claim 1, wherein the film is formed on both the second inclined surface provided so as to be in contact with the magnetic field. A rectangular plate-shaped body,
A first magnetic field including at least a pinned layer and formed on a slant surface of a first slant surface provided along a first direction in an in-plane direction of the flat surface of the main body with the first direction as a longitudinal direction. A resistance effect element;
On the inclined surface of the second inclined surface that includes at least a pinned layer and is provided along a second orientation different from the first orientation, in the in-plane direction of the flat surface of the main body portion. A second magnetoresistive element formed as a longitudinal direction,
With
The first magnetoresistive effect element is disposed in a first region arranged in the center among three regions in which the flat surface of the main body is partitioned by a straight line parallel to one side of the main body. 2. The magnetic sensor according to claim 1, wherein the second magnetoresistive element is disposed in each of the second region and the third region disposed on both sides of the one region. The first magnetoresistive element disposed in the first region has a component in which the orientation of magnetization of the pinned layer faces at least one orientation orthogonal to the flat surface,
The second magnetoresistive element disposed in the second region has a component in which the magnetization direction of the pinned layer faces at least one direction parallel to the flat surface,
The second magnetoresistive element arranged in the third region has a component in which the magnetization direction of the pinned layer faces at least another direction parallel to the flat surface. Item 8. The magnetic sensor according to Item 7. In the first magnetoresistive element and the second magnetoresistive element, the flat surface of the main body is orthogonal to a boundary line that divides each of the first region, the second region, and the third region. The magnetic sensor according to claim 7, wherein the magnetic sensor is arranged on one side of two regions divided into two equal parts.

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