Magnetic sensor

Abstract

To realize a magnetic sensor capable of reducing a strength of a magnetic field for setting / resetting magnetization of magnetic detection elements each disposed on an inclined surface.SOLUTION: A magnetic sensor 1 includes: a substrate 301 including a top surface 301a; an insulating layer 305 including an inclined surface 305e; and a MR element 50 disposed on the inclined surface 305e. The MR element 50 includes a first side surface 50c and a second side surface 50d. The first side surface 50c is located at a position forward in a first direction D1 that is one direction along the inclined surface 305e. The second side surface 50d is located at a position forward in a second direction D2 that is another direction along the inclined surface 305e. The MR element 50 includes a first non-constant portion 501 in which a gap between an upper end Ec1 of the first side surface 50c and an upper end Ed1 of the second side surface 50d becomes smaller along a longitudinal direction D3.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to a magnetic sensor including a magnetic detection element disposed on an inclined surface.

Background Art

[0002] In recent years, magnetic sensors using magnetoresistive elements have been used in various applications. In a system including a magnetic sensor, there are cases where it is desired to detect a magnetic field including a component in a direction perpendicular to the surface of a substrate by a magnetoresistive element provided on the substrate. In this case, by providing a soft magnetic material that converts a magnetic field in a direction perpendicular to the surface of the substrate into a magnetic field in a direction parallel to the surface of the substrate, or by disposing the magnetoresistive element on an inclined surface formed on the substrate, a magnetic field including a component in a direction perpendicular to the surface of the substrate can be detected.

[0003] As the magnetoresistive element, for example, a spin valve type magnetoresistive element is used. The spin valve type magnetoresistive element has a magnetization fixed layer having a magnetization with a fixed direction, a free layer having a magnetization whose direction can change according to the direction of an applied magnetic field, and a gap layer disposed between the magnetization fixed layer and the free layer. Further, for the free layer, a technique for setting / resetting the direction of the magnetization of the free layer using a coil is known.

[0004] Patent Document 1 discloses a magnetic sensor including a magnetoresistive element formed on an inclined surface. Patent Document 2 discloses a technique for setting / resetting the magnetic domain of a magnetic element using a coil.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] In cases where a magnetoresistive element is formed on an inclined surface, such as the magnetic sensor disclosed in Patent Document 1, and the magnetization direction of the free layer is set to a predetermined direction using the technique disclosed in Patent Document 2, depending on the shape of the magnetoresistive element, it was necessary to increase the strength of the magnetic field required to set the magnetization direction of the free layer to a predetermined direction to a certain extent.

[0007] The present invention has been made in view of the above problems, and its objective is to provide a magnetic sensor equipped with a magnetic detection element arranged on an inclined surface that can reduce the strength of the magnetic field used to set / reset the magnetization of the magnetic detection element. [Means for solving the problem]

[0008] The magnetic sensor of the present invention comprises a substrate having a reference plane, a support member disposed on the substrate and having an inclined surface tilted with respect to the reference plane, and a magnetic detection element disposed on the inclined surface and having a shape elongated in one direction. The magnetic detection element has a first side surface and a second side surface located on both sides in the short direction of the magnetic detection element and each having an upper end located at the end in the direction away from the reference plane. The first side surface is in the direction along the inclined surface and is located at the end of the first direction away from the reference plane. The second side surface is in the direction along the inclined surface and is located at the end of the second direction approaching the reference plane. The magnetic detection element includes a first change portion in which at least a portion of each of the upper ends of the first side surface and the upper end of the second side surface becomes linear and the distance between the upper ends of the first side surface and the upper end of the second side surface decreases along the longitudinal direction of the magnetic detection element. [Effects of the Invention]

[0009] In the magnetic sensor of the present invention, the magnetic detection element includes a first variable portion. This provides the effect that, according to the present invention, in a magnetic sensor equipped with a magnetic detection element positioned on an inclined surface, the strength of the magnetic field required to set / reset the magnetization of the magnetic detection element can be reduced. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view showing a magnetic sensor according to the first embodiment of the present invention. [Figure 2] This is a functional block diagram showing the configuration of a magnetic sensor device including a magnetic sensor according to the first embodiment of the present invention. [Figure 3] This is a circuit diagram showing the circuit configuration of the first detection circuit in the first embodiment of the present invention. [Figure 4] This is a circuit diagram showing the circuit configuration of the second detection circuit in the first embodiment of the present invention. [Figure 5] This is a plan view showing a part of a magnetic sensor according to the first embodiment of the present invention. [Figure 6] This is a cross-sectional view showing a part of a magnetic sensor according to the first embodiment of the present invention. [Figure 7] This is a side view showing a magnetoresistive element in the first embodiment of the present invention. [Figure 8] This is a cross-sectional view showing the main part of a magnetic sensor according to the first embodiment of the present invention. [Figure 9] This is a cross-sectional view showing a first example of the shape of the upper surface of a magnetoresistive element in the first embodiment of the present invention. [Figure 10] This is a cross-sectional view showing a second example of the shape of the upper surface of a magnetoresistive element in the first embodiment of the present invention. [Figure 11] This is a cross-sectional view showing a third example of the shape of the upper surface of the magnetoresistive element in the first embodiment of the present invention. [Figure 12] This is a plan view showing a first example of the shapes of the first and second side surfaces of the magnetoresistive element in the first embodiment of the present invention. [Figure 13] It is a plan view showing a second example of the shapes of the first and second side surfaces of the magnetoresistive element in the first embodiment of the present invention. [Figure 14] It is a plan view showing a third example of the shapes of the first and second side surfaces of the magnetoresistive element in the first embodiment of the present invention. [Figure 15] It is a cross-sectional view showing a part of a magnetic sensor according to a second embodiment of the present invention. [Embodiments for Carrying Out the Invention]

[0011] [First Embodiment] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, referring to FIGS. 1 and 2, the configuration of a magnetic sensor according to the first embodiment of the present invention will be described. FIG. 1 is a perspective view showing the magnetic sensor according to the present embodiment. FIG. 2 is a functional block diagram showing the configuration of a magnetic sensor device including the magnetic sensor according to the present embodiment.

[0012] As shown in FIG. 1, the magnetic sensor 1 has the form of a rectangular parallelepiped chip. The magnetic sensor 1 has an upper surface 1a and a lower surface located on opposite sides of each other, and four side surfaces connecting the upper surface 1a and the lower surface. Further, the magnetic sensor 1 has a plurality of electrode pads provided on the upper surface 1a.

[0013] Here, referring to FIG. 1, the reference coordinate system in the present embodiment will be described. The reference coordinate system is a coordinate system based on the magnetic sensor 1 and is a rectangular coordinate system defined by three axes. In the reference coordinate system, the X direction, the Y direction, and the Z direction are defined. The X direction, the Y direction, and the Z direction are orthogonal to each other. In particular, in the present embodiment, the direction perpendicular to the upper surface 1a of the magnetic sensor 1 and from the lower surface of the magnetic sensor 1 toward the upper surface 1a is defined as the Z direction. Also, the direction opposite to the X direction is defined as the -X direction, the direction opposite to the Y direction is defined as the -Y direction, and the direction opposite to the Z direction is defined as the -Z direction. The three axes defining the reference coordinate system are an axis parallel to the X direction, an axis parallel to the Y direction, and an axis parallel to the Z direction.

[0014] Hereinafter, a position that is ahead in the Z direction with respect to the reference position is referred to as "above", and a position that is on the opposite side of "above" with respect to the reference position is referred to as "below". Also, regarding the components of the magnetic sensor 1, the surface located at the end in the Z direction is referred to as the "upper surface", and the surface located at the end in the -Z direction is referred to as the "lower surface". Also, the expression "when viewed from the Z direction" means viewing the object from a position separated in the Z direction.

[0015] As shown in FIG. 2, the magnetic sensor 1 includes a first detection circuit 20 and a second detection circuit 30. Each of the first and second detection circuits 20, 30 includes a plurality of magnetic detection elements and is configured to detect a target magnetic field and generate at least one detection signal. In particular, in the present embodiment, the plurality of magnetic detection elements are a plurality of magnetoresistive effect elements. Hereinafter, the magnetoresistive effect element is referred to as a MR element.

[0016] The plurality of detection signals generated by the first and second detection circuits 20, 30 are processed by the processor 40. The magnetic sensor 1 and the processor 40 constitute the magnetic sensor device 100. The processor 40 is configured to generate a first detection value and a second detection value having a correspondence relationship with components in two different directions of the magnetic field at a predetermined reference position by processing the plurality of detection signals generated by the first and second detection circuits 20, 30. In particular, in the present embodiment, the above two different directions are one direction parallel to the XY plane and a direction parallel to the Z direction. The processor 40 is constituted by, for example, an application specific integrated circuit (ASIC).

[0017] The processor 40 may be included, for example, in a support that supports the magnetic sensor 1. This support has a plurality of electrode pads. The first and second detection circuits 20, 30 and the processor 40 are connected, for example, via a plurality of electrode pads of the magnetic sensor 1, a plurality of electrode pads of the support, and a plurality of bonding wires. If the plurality of electrode pads of the magnetic sensor 1 are provided on the upper surface 1a of the magnetic sensor 1, the magnetic sensor 1 may be mounted on the upper surface of the support in a orientation where the lower surface of the magnetic sensor 1 faces the upper surface of the support.

[0018] Next, the first and second detection circuits 20 and 30 will be described with reference to Figures 3 to 6. Figure 3 is a circuit diagram showing the circuit configuration of the first detection circuit 20. Figure 4 is a circuit diagram showing the circuit configuration of the second detection circuit 30. Figure 5 is a plan view showing a part of the magnetic sensor 1. Figure 6 is a cross-sectional view showing a part of the magnetic sensor 1.

[0019] Here, as shown in Figure 5, the U and V directions are defined as follows: The U direction is the direction of rotation from the X direction toward the -Y direction. The V direction is the direction of rotation from the Y direction toward the X direction. In this embodiment, the U direction is specifically defined as the direction of rotation by α from the X direction toward the -Y direction, and the V direction is defined as the direction of rotation by α from the Y direction toward the X direction. Note that α is an angle greater than 0° and less than 90°. In one example, α is 45°. Furthermore, the direction opposite to the U direction is defined as the -U direction, and the direction opposite to the V direction is defined as the -V direction.

[0020] Furthermore, as shown in Figure 6, the W1 and W2 directions are defined as follows: The W1 direction is the direction of rotation from the V direction toward the -Z direction. The W2 direction is the direction of rotation from the V direction toward the Z direction. In this embodiment, the W1 direction is specifically defined as the direction of rotation by β from the V direction toward the -Z direction, and the W2 direction is defined as the direction of rotation by β from the V direction toward the Z direction. Note that β is an angle greater than 0° and less than 90°. The direction opposite to the W1 direction is defined as the -W1 direction, and the direction opposite to the W2 direction is defined as the -W2 direction. The W1 and W2 directions are orthogonal to the U direction, respectively.

[0021] The first detection circuit 20 is configured to detect a component of the target magnetic field parallel to the W1 direction and to generate at least one first detection signal corresponding to this component. The second detection circuit 30 is configured to detect a component of the target magnetic field parallel to the W2 direction and to generate at least one second detection signal corresponding to this component.

[0022] As shown in Figure 3, the first detection circuit 20 includes a power supply terminal V2, a ground terminal G2, signal output terminals E21 and E22, a first resistor R21, a second resistor R22, a third resistor R23, and a fourth resistor R24. The multiple MR elements of the first detection circuit 20 constitute the first to fourth resistors R21, R22, R23, and R24.

[0023] The first resistor R21 is located between the power supply terminal V2 and the signal output terminal E21. The second resistor R22 is located between the signal output terminal E21 and the ground terminal G2. The third resistor R23 is located between the signal output terminal E22 and the ground terminal G2. The fourth resistor R24 ​​is located between the power supply terminal V2 and the signal output terminal E22.

[0024] As shown in Figure 4, the second detection circuit 30 includes a power supply terminal V3, a ground terminal G3, signal output terminals E31 and E32, a first resistor R31, a second resistor R32, a third resistor R33, and a fourth resistor R34. The multiple MR elements of the second detection circuit 30 constitute the first to fourth resistors R31, R32, R33, and R34.

[0025] The first resistor R31 is located between the power supply terminal V3 and the signal output terminal E31. The second resistor R32 is located between the signal output terminal E31 and the ground terminal G3. The third resistor R33 is located between the signal output terminal E32 and the ground terminal G3. The fourth resistor R34 is located between the power supply terminal V3 and the signal output terminal E32.

[0026] A predetermined voltage or current is applied to each of the power supply terminals V2 and V3. Each of the ground terminals G2 and G3 is connected to ground.

[0027] Hereinafter, the multiple MR elements of the first detection circuit 20 will be referred to as multiple first MR elements 50B, and the multiple MR elements of the second detection circuit 30 will be referred to as multiple second MR elements 50C. Since the first and second detection circuits 20 and 30 are components of the magnetic sensor 1, it can also be said that the magnetic sensor 1 includes multiple first MR elements 50B and multiple second MR elements 50C. Furthermore, any MR element will be denoted by the reference numeral 50.

[0028] Figure 7 is a side view showing the MR element 50. The MR element 50 is a spin-valve type MR element that includes multiple magnetic layers. The MR element 50 has a magnetization fixed layer 52 having magnetization with a fixed direction, a free layer 54 having magnetization whose direction can change according to the direction of the target magnetic field, and a gap layer 53 disposed between the magnetization fixed layer 52 and the free layer 54. The MR element 50 may be a TMR (tunnel magnetoresistance) element or a GMR (giant magnetoresistance) element. In a TMR element, the gap layer 53 is a tunnel barrier layer. In a GMR element, the gap layer 53 is a non-magnetic conductive layer. In the MR element 50, the resistance value changes according to the angle that the direction of magnetization of the free layer 54 makes with respect to the direction of magnetization of the magnetization fixed layer 52. The resistance value is at its minimum when this angle is 0° and at its maximum when the angle is 180°. In each MR element 50, the free layer 54 has shape anisotropy such that its easy magnetization axis direction is perpendicular to the magnetization direction of the fixed magnetization layer 52. As a means of setting the easy magnetization axis of the free layer 54 in a predetermined direction, a magnet can be used to apply a bias magnetic field to the free layer 54. The fixed magnetization layer 52, gap layer 53, and free layer 54 are stacked in this order.

[0029] The MR element 50 further includes an antiferromagnetic layer 51. The antiferromagnetic layer 51, magnetization fixed layer 52, gap layer 53, and free layer 54 are stacked in this order. The antiferromagnetic layer 51 is made of an antiferromagnetic material and creates exchange coupling with the magnetization fixed layer 52 to fix the magnetization direction of the magnetization fixed layer 52. The magnetization fixed layer 52 may be a so-called self-pinned fixed layer (Synthetic Ferri Pinned layer, SFP layer). The self-pinned fixed layer has a stacked ferri structure in which a ferromagnetic layer, a non-magnetic intermediate layer, and a ferromagnetic layer are stacked, and the two ferromagnetic layers are antiferromagnetically coupled. If the magnetization fixed layer 52 is a self-pinned fixed layer, the antiferromagnetic layer 51 may be omitted.

[0030] Note that the arrangement of layers 51-54 in the MR element 50 may be reversed vertically from the arrangement shown in Figure 7.

[0031] In Figures 3 and 4, the filled arrows represent the direction of magnetization of the magnetization fixed layer 52 of the MR element 50. The open arrows represent the direction of magnetization of the free layer 54 of the MR element 50 when no target magnetic field is applied to the MR element 50.

[0032] In the example shown in Figure 3, the magnetization direction of the magnetization fixed layer 52 in each of the first and third resistive sections R21 and R23 is in the W1 direction. The magnetization direction of the magnetization fixed layer 52 in each of the second and fourth resistive sections R22 and R24 is in the -W1 direction. Furthermore, each free layer 54 of the multiple first MR elements 50B has shape anisotropy such that the easy magnetization axis direction is parallel to the U direction. The magnetization direction of the free layer 54 in each of the first and second resistive sections R21 and R22 is in the U direction when no target magnetic field is applied to the first MR element 50B. In the above case, the magnetization direction of the free layer 54 in each of the third and fourth resistive sections R23 and R24 is in the -U direction.

[0033] In the example shown in Figure 4, the magnetization direction of the magnetization fixed layer 52 in each of the first and third resistive sections R31 and R33 is in the W2 direction. The magnetization direction of the magnetization fixed layer 52 in each of the second and fourth resistive sections R32 and R34 is in the -W2 direction. Furthermore, each free layer 54 of the multiple second MR elements 50C has shape anisotropy such that the easy magnetization axis direction is parallel to the U direction. The magnetization direction of the free layer 54 in each of the first and second resistive sections R31 and R32 is in the U direction when no target magnetic field is applied to the second MR element 50C. In the above case, the magnetization direction of the free layer 54 in each of the third and fourth resistive sections R33 and R34 is in the -U direction.

[0034] The magnetic sensor 1 includes a magnetic field generator configured to apply a magnetic field in a predetermined direction to the free layer 54 of each of the multiple first MR elements 50B and multiple second MR elements 50C. In this embodiment, the magnetic field generator includes a coil 80 that applies a magnetic field in a predetermined direction to the free layer 54 of each of the multiple first MR elements 50B and multiple second MR elements 50C.

[0035] Furthermore, the direction of magnetization of the fixed magnetization layer 52 and the direction of the easy magnetization axis of the free layer 54 may be slightly deviated from the above-mentioned direction from the viewpoint of the accuracy of fabrication of the MR element 50. Also, the magnetization of the fixed magnetization layer 52 may be configured to include a magnetization component whose main component is the direction described above. In this case, the direction of magnetization of the fixed magnetization layer 52 will be the direction described above or approximately the direction described above.

[0036] In this embodiment, the MR element 50 is configured such that current flows in the stacking direction of multiple magnetic layers, namely the magnetized fixed layer 52 and the free layer 54. As will be described later, the magnetic sensor 1 is equipped with a lower electrode and an upper electrode for supplying current to the MR element 50. The MR element 50 is positioned between the lower electrode and the upper electrode.

[0037] The specific structure of the magnetic sensor 1 will be described in detail below with reference to Figures 5 and 6. Figure 6 shows a portion of the cross-section at the position indicated by line 6-6 in Figure 5.

[0038] The magnetic sensor 1 includes a substrate 301 having an upper surface 301a, insulating layers 302, 303, 304, 305, 307, 308, 309, 310, a plurality of lower electrodes 61B, a plurality of lower electrodes 61C, a plurality of upper electrodes 62B, a plurality of upper electrodes 62C, a plurality of lower coil elements 81, and a plurality of upper coil elements 82. The upper surface 301a of the substrate 301 is assumed to be parallel to the XY plane. The Z direction is also a direction perpendicular to the upper surface 301a of the substrate 301. Note that a coil element is a part of the winding of a coil.

[0039] The insulating layer 302 is placed on the substrate 301. Multiple lower coil elements 81 are placed on the insulating layer 302. The insulating layer 303 is placed on the insulating layer 302 around the multiple lower coil elements 81. Insulating layers 304 and 305 are laminated in this order on the multiple lower coil elements 81 and insulating layer 303.

[0040] Multiple lower electrodes 61B and multiple lower electrodes 61C are arranged on an insulating layer 305. An insulating layer 307 is arranged on the insulating layer 305 around the multiple lower electrodes 61B and multiple lower electrodes 61C. Multiple first MR elements 50B are arranged on the multiple lower electrodes 61B. Multiple second MR elements 50C are arranged on the multiple lower electrodes 61C. An insulating layer 308 is arranged on the multiple lower electrodes 61B, multiple lower electrodes 61C and insulating layer 307 around the multiple first MR elements 50B and multiple second MR elements 50C. Multiple upper electrodes 62B are arranged on the multiple first MR elements 50B and insulating layer 308. Multiple upper electrodes 62C are arranged on the multiple second MR elements 50C and insulating layer 308. An insulating layer 309 is arranged on the insulating layer 308 around the multiple upper electrodes 62B and multiple upper electrodes 62C.

[0041] The insulating layer 310 is positioned on a plurality of upper electrodes 62B, a plurality of upper electrodes 62C, and an insulating layer 309. A plurality of upper coil elements 82 are positioned on the insulating layer 310. The magnetic sensor 1 may further include an insulating layer (not shown) covering the plurality of upper coil elements 82 and the insulating layer 310.

[0042] The magnetic sensor 1 includes a support member that supports a plurality of first MR elements 50B and a plurality of second MR elements 50C. The support member has at least one inclined surface that is inclined with respect to the upper surface 301a of the substrate 301. In this embodiment in particular, the support member is composed of an insulating layer 305. Figure 5 shows the insulating layer 305, the plurality of first MR elements 50B, the plurality of second MR elements 50C, and the plurality of upper coil elements 82 among the components of the magnetic sensor 1.

[0043] The insulating layer 305 has a plurality of convex surfaces 305c that protrude in the direction away from the upper surface 301a of the substrate 301 (Z direction). Each of the plurality of convex surfaces 305c extends in a direction parallel to the U direction. The overall shape of the convex surface 305c is a semi-cylindrical curved surface formed by moving the curved shape (arch shape) of the convex surface 305c shown in Figure 6 along a direction parallel to the U direction. Furthermore, the plurality of convex surfaces 305c are arranged at predetermined intervals in a direction parallel to the V direction.

[0044] Each of the multiple convex surfaces 305c has an upper end that is furthest from the upper surface 301a of the substrate 301. In this embodiment, the upper end of each of the multiple convex surfaces 305c is assumed to extend in a direction parallel to the U direction. Now, let us focus on any one of the multiple convex surfaces 305c. The convex surface 305c includes a first inclined surface 305a and a second inclined surface 305b. The first inclined surface 305a is the surface of the convex surface 305c that is on the V direction side of the upper end of the convex surface 305c. The second inclined surface 305b is the surface of the convex surface 305c that is on the -V direction side of the upper end of the convex surface 305c. In Figure 5, the boundary between the first inclined surface 305a and the second inclined surface 305b is shown by a dotted line.

[0045] The upper end of the convex surface 305c may be the boundary between the first inclined surface 305a and the second inclined surface 305b. In this case, the dotted line shown in Figure 5 indicates the upper end of the convex surface 305c.

[0046] The upper surface 301a of the substrate 301 is parallel to the XY plane. The first inclined surface 305a and the second inclined surface 305b are each inclined with respect to the upper surface 301a of the substrate 301, i.e., the XY plane. In a cross section perpendicular to the upper surface 301a of the substrate 301, the distance between the first inclined surface 305a and the second inclined surface 305b decreases as the distance from the upper surface 301a of the substrate 301 increases.

[0047] In this embodiment, since there are multiple convex surfaces 305c, there are also multiple first inclined surfaces 305a and multiple second inclined surfaces 305b. The insulating layer 305 has multiple first inclined surfaces 305a and multiple second inclined surfaces 305b.

[0048] The insulating layer 305 further has flat surfaces 305d surrounding the plurality of convex surfaces 305c. The flat surfaces 305d are parallel to the upper surface 301a of the substrate 301. Each of the plurality of convex surfaces 305c protrudes from the flat surfaces 305d in the Z direction. In this embodiment, the plurality of convex surfaces 305c are arranged with a predetermined interval between them. Therefore, a flat surface 305d exists between two adjacent convex surfaces 305c in the V direction.

[0049] The insulating layer 305 includes a plurality of protrusions projecting in the Z direction and flat portions surrounding the plurality of protrusions. Each of the plurality of protrusions extends in a direction parallel to the U direction and has a convex surface 305c. The plurality of protrusions are arranged at predetermined intervals in a direction parallel to the V direction. The thickness (dimension in the Z direction) of the flat portions is substantially constant. The insulating layer 304 has a substantially constant thickness (dimension in the Z direction) and is formed along the lower surface of the insulating layer 305.

[0050] Multiple lower electrodes 61B are arranged on multiple first inclined surfaces 305a. Multiple lower electrodes 61C are arranged on multiple second inclined surfaces 305b. As described above, since each of the first inclined surface 305a and the second inclined surface 305b is inclined with respect to the upper surface 301a of the substrate 301, i.e., the XY plane, the upper surfaces of each of the multiple lower electrodes 61B and each of the multiple lower electrodes 61C are also inclined with respect to the XY plane. Therefore, it can be said that the multiple first MR elements 50B and the multiple second MR elements 50C are arranged on inclined surfaces that are inclined with respect to the XY plane. The insulating layer 305 is a member for supporting each of the multiple first MR elements 50B and the multiple second MR elements 50C so that they are inclined with respect to the XY plane.

[0051] In this embodiment, the first inclined surface 305a is a curved surface. Therefore, the first MR element 50B curves along the curved surface (first inclined surface 305a). In this embodiment, for convenience, the direction of magnetization of the magnetization fixed layer 52 of the first MR element 50B is defined as a linear direction as described above. The W1 direction and -W1 direction, which are the directions of magnetization of the magnetization fixed layer 52 of the first MR element 50B, are also the directions in which the tangents that are in contact with the portion of the first inclined surface 305a near the first MR element 50B extend.

[0052] Similarly, in this embodiment, the second inclined surface 305b is a curved surface. Therefore, the second MR element 50C curves along the curved surface (second inclined surface 305b). In this embodiment, for convenience, the direction of magnetization of the magnetization fixed layer 52 of the second MR element 50C is defined as a linear direction as described above. The W2 direction and -W2 direction, which are the directions of magnetization of the magnetization fixed layer 52 of the second MR element 50C, are also the directions in which the tangents that are in contact with the portion of the second inclined surface 305b near the second MR element 50C extend.

[0053] As shown in Figure 5, the multiple first MR elements 50B are arranged so that multiple elements are lined up in the U direction and multiple elements are lined up in the V direction. Multiple first MR elements 50B are lined up in a row on one first inclined surface 305a. Similarly, the multiple second MR elements 50C are arranged so that multiple elements are lined up in the U direction and multiple elements are lined up in the V direction. Multiple second MR elements 50C are lined up in a row on one second inclined surface 305b. In this embodiment, the rows of multiple first MR elements 50B and rows of multiple second MR elements 50C are arranged alternately in a direction parallel to the V direction.

[0054] Furthermore, an adjacent first MR element 50B and a second MR element 50C may or may not be offset in a direction parallel to the U direction when viewed from the Z direction. Also, two first MR elements 50B adjacent to each other with one second MR element 50C in between may or may not be offset in a direction parallel to the U direction when viewed from the Z direction. Also, two second MR elements 50C adjacent to each other with one first MR element 50B in between may or may not be offset in a direction parallel to the U direction when viewed from the Z direction.

[0055] Multiple first MR elements 50B are connected in series by multiple lower electrodes 61B and multiple upper electrodes 62B. The connection method of the multiple first MR elements 50B will now be described in detail with reference to Figure 7. In Figure 7, reference numeral 61 indicates a lower electrode corresponding to any MR element 50, and reference numeral 62 indicates an upper electrode corresponding to any MR element 50. As shown in Figure 7, each lower electrode 61 has an elongated shape. A gap is formed between two adjacent lower electrodes 61 in the longitudinal direction. On the upper surface of the lower electrode 61, MR elements 50 are positioned near both ends in the longitudinal direction. Each upper electrode 62 also has an elongated shape and is positioned on two adjacent lower electrodes 61 in the longitudinal direction to electrically connect two adjacent MR elements 50.

[0056] Although not shown, one MR element 50 located at the end of a row of multiple MR elements 50 arranged in a single line is connected to another MR element 50 located at the end of an adjacent row of multiple MR elements 50 in a direction intersecting the longitudinal direction of the lower electrode 61. These two MR elements 50 are connected to each other by electrodes (not shown). The electrodes (not shown) may be electrodes connecting the lower surfaces of the two MR elements 50 or the upper surfaces of the two MR elements 50.

[0057] If the MR element 50 shown in Figure 7 is the first MR element 50B, then the lower electrode 61 shown in Figure 7 corresponds to the lower electrode 61B, and the upper electrode 62 shown in Figure 7 corresponds to the upper electrode 62B. In this case, the longitudinal direction of the lower electrode 61 is parallel to the U direction.

[0058] Similarly, multiple second MR elements 50C are connected in series by multiple lower electrodes 61C and multiple upper electrodes 62C. The explanation of the connection method for multiple first MR elements 50B described above also applies to the connection method for multiple second MR elements 50C. When the MR element 50 shown in Figure 7 is a second MR element 50C, the lower electrode 61 shown in Figure 7 corresponds to the lower electrode 61C, and the upper electrode 62 shown in Figure 7 corresponds to the upper electrode 62C. In this case, the longitudinal direction of the lower electrode 61 is parallel to the U direction.

[0059] Each of the multiple upper coil elements 82 extends in a direction parallel to the Y direction. Furthermore, the multiple upper coil elements 82 are arranged so as to be aligned in the X direction. In this embodiment in particular, when viewed from the Z direction, two upper coil elements 82 overlap each of the multiple first MR elements 50B and the multiple second MR elements 50C.

[0060] Each of the multiple lower coil elements 81 extends in a direction parallel to the Y direction. Furthermore, the multiple lower coil elements 81 are arranged so as to be aligned in the X direction. The shape and arrangement of the multiple lower coil elements 81 may be the same as or different from the shape and arrangement of the multiple upper coil elements 82. In the examples shown in Figures 5 and 6, the X-direction dimension of each of the multiple lower coil elements 81 is smaller than the X-direction dimension of each of the multiple upper coil elements 82. Also, the distance between two adjacent lower coil elements 81 in the X direction is smaller than the distance between two adjacent upper coil elements 82 in the X direction.

[0061] In the examples shown in Figures 5 and 6, the multiple lower coil elements 81 and the multiple upper coil elements 82 are electrically connected to form a coil 80 that applies a magnetic field parallel to the X direction to the free layers 54 of each of the multiple first MR elements 50B and the multiple second MR elements 50C. The coil 80 may also be configured to apply a magnetic field in the X direction to the free layers 54 of the first and second resistors R21, R22 of the first detection circuit 20 and the first and second resistors R31, R32 of the second detection circuit 30, and to apply a magnetic field in the -X direction to the free layers 54 of the third and fourth resistors R23, R24 of the first detection circuit 20 and the third and fourth resistors R33, R34 of the second detection circuit 30. The coil 80 may also be controlled by the processor 40.

[0062] Next, the first and second detection signals will be described. First, the first detection signal will be described with reference to Figure 3. When the intensity of the component of the target magnetic field parallel to the W1 direction changes, the resistance values ​​of each of the resistors R21 to R24 of the first detection circuit 20 change such that the resistance values ​​of resistors R21 and R23 increase while the resistance values ​​of resistors R22 and R24 decrease, or the resistance values ​​of resistors R21 and R23 decrease while the resistance values ​​of resistors R22 and R24 increase. As a result, the potentials of the signal output terminals E21 and E22 change. The first detection circuit 20 is configured to generate a signal corresponding to the potential of the signal output terminal E21 as the first detection signal S21, and a signal corresponding to the potential of the signal output terminal E22 as the first detection signal S22.

[0063] Next, the second detection signal will be described with reference to Figure 4. When the intensity of the component of the target magnetic field parallel to the W2 direction changes, the resistance values ​​of the resistors R31 to R34 of the second detection circuit 30 change such that the resistance values ​​of resistors R31 and R33 increase while the resistance values ​​of resistors R32 and R34 decrease, or the resistance values ​​of resistors R31 and R33 decrease while the resistance values ​​of resistors R32 and R34 increase. As a result, the potentials of the signal output terminals E31 and E32 change. The second detection circuit 30 is configured to generate a signal corresponding to the potential of the signal output terminal E31 as the second detection signal S31, and a signal corresponding to the potential of the signal output terminal E32 as the second detection signal S32.

[0064] Next, the operation of the processor 40 will be described. The processor 40 is configured to generate a first detection value and a second detection value based on the first detection signals S21, S22 and the second detection signals S31, S32. The first detection value is the detection value corresponding to the component of the target magnetic field in the direction parallel to the V direction. The second detection value is the detection value corresponding to the component of the target magnetic field in the direction parallel to the Z direction. Hereafter, the first detection value will be denoted by the symbol Sv and the second detection value will be denoted by the symbol Sz.

[0065] The processor 40 generates the first and second detection values ​​Sv and Sz, for example, as follows: First, the processor 40 generates value S1 by an operation that includes calculating the difference S21-S22 between the first detection signal S21 and the first detection signal S22, and then generates value S2 by an operation that includes calculating the difference S31-S32 between the second detection signal S31 and the second detection signal S32. Next, the processor 40 calculates values ​​S3 and S4 using the following equations (1) and (2).

[0066] S3 = (S2 + S1) / (2cosα) …(1) S4 = (S2 - S1) / (2sinα) …(2)

[0067] The first detected value Sv may be the value S3 itself, or it may be the value S3 to which predetermined corrections such as gain adjustment and offset adjustment have been applied. Similarly, the second detected value Sz may be the value S4 itself, or it may be the value S4 to which predetermined corrections such as gain adjustment and offset adjustment have been applied.

[0068] Next, the structural features of the magnetic sensor 1 according to this embodiment will be described. Figure 8 is a cross-sectional view showing the main part of the magnetic sensor 1.

[0069] Figure 8 shows a cross-section that intersects with an MR element 50 placed on an arbitrary inclined surface 305e, and is parallel to the VZ plane. Hereinafter, a cross-section parallel to the VZ plane will be referred to as a VZ cross-section. The VZ cross-section shown in Figure 8 may also be a VZ cross-section viewed from a position at the end of the U direction, similar to Figure 6. In this case, the MR element 50, the lower electrode 61, and the inclined surface 305e correspond to the first MR element 50B, the lower electrode 61B, and the first inclined surface 305a, respectively. Alternatively, the VZ cross-section shown in Figure 8 may also be a VZ cross-section viewed from a position at the end of the -U direction. In this case, the MR element 50, the lower electrode 61, and the inclined surface 305e correspond to the second MR element 50C, the lower electrode 61C, and the second inclined surface 305b, respectively.

[0070] Here, as shown in Figure 8, we define a first direction D1 and a second direction D2 that are parallel to the VZ plane. The first direction D1 is the direction along the inclined surface 305e and away from the reference plane. In this embodiment, the upper surface 301a of the substrate 301 (see Figure 6) is used as the reference plane. The Z direction is a single direction perpendicular to the reference plane (upper surface 301a of the substrate 301). The second direction D2 is the direction along the inclined surface 305e and approaching the reference plane (upper surface 301a of the substrate 301).

[0071] Furthermore, in the following explanation, the direction that is along the inclined surface 305e and parallel to the first direction D1 (parallel to the second direction D2) is simply referred to as the direction along the inclined surface 305e. This direction is both the direction along the inclined surface 305e and the direction in which the distance from the reference plane (the upper surface 301a of the substrate 301) changes.

[0072] As mentioned above, the MR element 50 has shape anisotropy such that its easy magnetization axis direction is parallel to the U direction. That is, the MR element 50 has a shape that is elongated in the direction parallel to the U direction. The VZ cross section is perpendicular to the longitudinal direction of the MR element 50. The "direction along the inclined surface 305e" as defined above is also the short-side direction of the MR element 50.

[0073] The MR element 50 has a lower surface 50a facing the inclined surface 305e, an upper surface 50b opposite to the lower surface 50a, and a first side surface 50c and a second side surface 50d located on both sides in the short direction (direction along the inclined surface 305e) of the MR element 50. The first side surface 50c is located at the end of the first direction D1. The second side surface 50d is located at the end of the second direction D2.

[0074] The first side surface 50c has an upper end Ec1 located at the end in the direction away from the upper surface 301a of the substrate 301, i.e., in the Z direction, and a lower end Ec2 located at the end in the direction approaching the upper surface 301a of the substrate 301, i.e., in the -Z direction. The second side surface 50d has an upper end Ed1 located at the end in the direction away from the upper surface 301a of the substrate 301, i.e., in the Z direction, and a lower end Ed2 located at the end in the direction approaching the upper surface 301a of the substrate 301, i.e., in the -Z direction.

[0075] The lower electrode 61 is interposed between the MR element 50 and the inclined surface 305e. The lower electrode 61 has a lower surface 61a facing the inclined surface 305e, an upper surface 61b opposite to the lower surface 61a, and two sides (see Figure 6) connecting the lower surface 61a and the upper surface 61b. The lower electrode 61 may be formed extending from the inclined surface 305e to the flat surface 305d. In this case, one of the two sides of the lower electrode 61 is positioned on the inclined surface 305e, and the other is positioned on the flat surface 305d. Alternatively, the entire lower electrode 61 may be positioned on the inclined surface 305e. In this case, both sides of the lower electrode 61 are positioned on the inclined surface 305e.

[0076] Next, the shape of the MR element 50 will be described in detail. First, a first example of the top surface 50b of the MR element 50 will be described with reference to Figure 9. Figure 9 is a plan view showing a first example of the top surface 50b of the MR element 50. Hereafter, the longitudinal direction of the MR element 50 (the direction parallel to the U direction) will be represented by the symbol D3.

[0077] The upper end Ec1 of the first side surface 50c includes a first portion Sc1, a second portion Sc2, and a third portion Sc3 connecting the first portion Sc1 and the second portion Sc2. The upper end Ed1 of the second side surface 50d includes a first portion Sd1, a second portion Sd2, and a third portion Sd3 connecting the first portion Sd1 and the second portion Sd2. The first to third portions Sc1 to Sc3 and the first to third portions Sd1 to Sd3 constitute the outer edge of the upper surface 50b of the MR element 50.

[0078] At least a portion of each of the first to third parts Sc1 to Sc3 and the first to third parts Sd1 to Sd3 is linear. In this invention, "linear" includes both cases where it is actually a straight line and cases where it can be considered to extend along a virtual straight line when viewed from the Z direction. In particular, the first parts Sc1, Sd1 and the second part Sc2, Sd2These extend along virtual straight lines Lc1, Ld1, Lc2, and Ld2, respectively. Each of the virtual straight lines Lc1, Ld1, Lc2, and Ld2 is inclined with respect to the longitudinal direction D3 and the upper surface 301a of the substrate 301, respectively. If the inclined surface 305e is curved, then strictly speaking, each of the first portion Sc1, Sd1 and the second portion Sc2, Sd2 is also curved.

[0079] Edges may be formed between the first part Sc1 and the third part Sc3, between the second part Sc2 and the third part Sc3, between the first part Sd1 and the third part Sd3, between the second part Sd2 and the third part Sd3, between the first part Sc1 and the first part Sd1, and between the second part Sc2 and the second part Sd2. The edges may be pointed or rounded.

[0080] The MR element 50 includes a first variable portion 501, a second variable portion 502, and a constant portion 503 located between the first variable portion 501 and the second variable portion 502. In Figure 9, the boundary between the first variable portion 501 and the constant portion 503, and the boundary between the second variable portion 502 and the constant portion 503, are shown by dotted lines. The first variable portion 501, the constant portion 503, and the second variable portion 502 are arranged in this order along the longitudinal direction D3.

[0081] The first modified portion 501 has an upper surface portion 50b1 that constitutes a part of the upper surface 50b. The second modified portion 502 has an upper surface portion 50b2 that constitutes another part of the upper surface 50b. The constant portion 503 has an upper surface portion 50b3 that constitutes yet another part of the upper surface 50b.

[0082] The first portion Sc1,Sd1 constitutes the outer edge of the upper portion 50b1 of the first change portion 501. Therefore, in the first change portion 501, at least a portion of the upper end Ec1 of the first side surface 50c and the upper end Ed1 of the second side surface 50d are straight. Also, in the first change portion 501, along the longitudinal direction D3, the distance between the first side surface 50c and the second side surface 50d decreases, and the distance between the upper end Ec1 and the upper end Ed1 (the distance between the first portion Sc1 and the first portion Sd1) also decreases. These distances decrease as you move away from the constant portion 503.

[0083] In Figure 9, the symbol Lm represents a hypothetical straight line extending between the first side surface 50c and the second side surface 50d and parallel to the longitudinal direction D3. The first portion Sc1 makes an angle θc1 with respect to the hypothetical straight line Lm. The first portion Sd1 makes an angle θd1 with respect to the hypothetical straight line Lm. In the first example of the top surface 50b, angles θc1 and θd1 ​​are equal to or approximately equal to each other.

[0084] The sum of angles θc1 and θd1 ​​(θc1+θd1) represents the angle between the first part Sc1 and the first part Sd1. The sum of angles θc1 and θd1 ​​is preferably in the range of 5° to 40°, and more preferably in the range of 10° to 25°.

[0085] The second modified portion 502 may have a shape symmetrical with respect to the first modified portion 501, centered on a virtual plane that intersects the MR element 50 and the longitudinal direction D3. The second portions Sc2 and Sd2 constitute the outer edge of the upper surface portion 50b2 of the second modified portion 502. Therefore, in the second modified portion 502, at least a portion of the upper end Ec1 of the first side surface 50c and the upper end Ed1 of the second side surface 50d are linear. Also, in the second modified portion 502, along the longitudinal direction D3, the distance between the first side surface 50c and the second side surface 50d decreases, and the distance between the upper end Ec1 and the upper end Ed1 (the distance between the second portion Sc2 and the second portion Sd2) also decreases. These distances decrease as you move away from the constant portion 503.

[0086] The second portion Sc2 makes an angle θc2 with respect to the imaginary line Lm. The second portion Sd2 makes an angle θd2 with respect to the imaginary line Lm. In the first example of the upper surface 50b, angles θc2 and θd2 are equal to each other or approximately equal to each other.

[0087] The sum of angles θc2 and θd2 (θc2+θd2) represents the angle between the second part Sc2 and the second part Sd2. The preferred range for the sum of angles θc2 and θd2 may be the same as the preferred range for the angle between the first part Sc1 and the first part Sd1.

[0088] In a certain portion 503, the distance between the first side surface 50c and the second side surface 50d may be constant regardless of the position in the longitudinal direction D3. Also, in a certain portion 503, the distance between the upper end Ec1 and the upper end Ed1 (the distance between the third portion Sc3 and the third portion Sd3) may be constant regardless of the position in the longitudinal direction D3.

[0089] Next, with reference to Figure 10, a second example of the upper surface 50b of the MR element 50 will be described. Figure 10 is a plan view showing a second example of the upper surface 50b of the MR element 50.

[0090] In the second example of the upper surface 50b, the relationship between angles θc1 and θd1, and the relationship between angles θc2 and θd2, are different from those in the first example of the upper surface 50b. In the second example of the upper surface 50b, angles θc1 and θd1 ​​are different from each other, and angles θc2 and θd2 are different from each other. In particular, in the second example of the upper surface 50b, angle θc1 is smaller than angle θd1, and angle θc2 is smaller than angle θd2.

[0091] In addition, in the second example of the upper surface 50b, the preferred range for the sum of angles θc1 and θd1 ​​(the angle formed by the first part Sc1 and the first part Sd1) and the preferred range for the sum of angles θc2 and θd2 (the angle formed by the second part Sc2 and the second part Sd2) may be the same as in the first example of the upper surface 50b.

[0092] Next, a third example of the upper surface 50b of the MR element 50 will be described with reference to Figure 11. Figure 11 is a plan view showing a third example of the upper surface 50b of the MR element 50.

[0093] In the third example of the upper surface 50b, the relationship between angles θc1 and θd1, and the relationship between angles θc2 and θd2, are different from those in the second example of the upper surface 50b. In the third example, angle θc1 is greater than angle θd1, and angle θc2 is greater than angle θd2.

[0094] In addition, in the third example of the upper surface 50b, the preferred range for the sum of angles θc1 and θd1 ​​(the angle formed by the first part Sc1 and the first part Sd1) and the preferred range for the sum of angles θc2 and θd2 (the angle formed by the second part Sc2 and the second part Sd2) may be the same as in the first example of the upper surface 50b.

[0095] Next, the planar shapes (shapes as seen from above) of the first and second sides 50c and 50d of the MR element 50 will be described in detail. First, with reference to Figure 12, a first example of the first and second sides 50c and 50d of the MR element 50 will be described. Figure 12 is a plan view showing a first example of the first and second sides 50c and 50d of the MR element 50.

[0096] The first side surface 50c has a tapered shape inclined with respect to the inclined surface 305e (see Figure 8). The lower end Ec2 of the first side surface 50c is located ahead of the first direction D1 when viewed from the upper end Ec1 of the first side surface 50c. The second side surface 50d also has a tapered shape inclined with respect to the inclined surface 305e (see Figure 8). The lower end Ed2 of the second side surface 50d is located ahead of the second direction D2 when viewed from the upper end Ed1 of the second side surface 50d.

[0097] The MR element 50 further has edges 50e1 and 50e2 formed by the intersection of the first side surface 50c and the second side surface 50d. Edge 50e1 is located at one end of the MR element 50 parallel to the longitudinal direction D3. Edge 50e2 is located at the other end of the MR element 50 parallel to the longitudinal direction D3.

[0098] In the first example of the first and second sides 50c and 50d, the dimensions of the first side 50c and the dimensions of the second side 50d in a cross section intersecting the MR element 50 and perpendicular to the longitudinal direction D3 are equal to or approximately equal to each other, regardless of the position in the cross section.

[0099] In Figure 12, the symbol Dc1 indicates the dimension of the first side surface 50c in a cross section that intersects the first change portion 501 and is perpendicular to the longitudinal direction D3. The symbol Dc3 indicates the dimension of the first side surface 50c in a cross section that intersects the constant portion 503 and is perpendicular to the longitudinal direction D3. Dimensions Dc1 and Dc3 are also dimensions of the first side surface 50c in the direction along the inclined surface 305e, and are dimensions of the first side surface 50c in the short direction of the MR element 50.

[0100] Furthermore, in Figure 12, the symbol Dd1 indicates the dimension of the second side surface 50d in a cross section that intersects with the first change portion 501 and is perpendicular to the longitudinal direction D3. Dd3 This is in a cross-section that intersects with a certain portion 503 and is perpendicular to the longitudinal direction D3. Second side 50d The dimensions are shown. Dd1, Dd3 Each of these is also the dimension of the second side surface 50d in the direction along the inclined surface 305e, and is also the dimension of the second side surface 50d in the short direction of the MR element 50.

[0101] The maximum value of dimension Dc1 and the maximum value of dimension Dd1 are equal to or approximately equal to each other. Also, the maximum value of dimension Dc3 and the maximum value of dimension Dd3 are equal to or approximately equal to each other. Furthermore, the maximum value of dimension Dc1 is greater than the maximum value of dimension Dc3, and the maximum value of dimension Dd1 is greater than the maximum value of dimension Dd3. Therefore, the sum of the maximum values ​​of dimension Dc1 and dimension Dd1 is equal to the dimension Dc3 It is greater than the sum of the maximum value of and the maximum value of dimension Dd3.

[0102] Furthermore, the maximum value of the dimension of the first side surface 50c in the cross section intersecting the second change portion 502 and perpendicular to the longitudinal direction D3 (hereinafter referred to as the first dimension), and the maximum value of the dimension of the second side surface 50d in the cross section intersecting the second change portion 502 and perpendicular to the longitudinal direction D3 (hereinafter referred to as the second dimension), are equal to or approximately equal to each other. Also, the maximum value of the first dimension is greater than the maximum value of dimension Dc3, and the maximum value of the second dimension is greater than the maximum value of dimension Dd3. Therefore, the sum of the maximum value of the first dimension and the maximum value of the second dimension is the dimension Dc3 It is greater than the sum of the maximum value of and the maximum value of dimension Dd3.

[0103] Next, with reference to Figure 13, a second example of the first and second sides 50c and 50d of the MR element 50 will be described. Figure 13 is a plan view showing a second example of the first and second sides 50c and 50d of the MR element 50.

[0104] In the second example of the first and second sides 50c and 50d, the dimensions of the first side 50c and the dimensions of the second side 50d in a cross section that intersects the MR element 50 and is perpendicular to the longitudinal direction D3 are different from each other. In particular, in the second example of the first and second sides 50c and 50d, regardless of the position of the cross section, the dimensions of the first side 50c in the cross section are larger than the dimensions of the second side 50d in the cross section.

[0105] Furthermore, the maximum value of dimension Dc1 is greater than the maximum value of dimension Dd1, and the maximum value of dimension Dc3 is greater than the maximum value of dimension Dd3. Also, the maximum value of the aforementioned first dimension is greater than the maximum value of the aforementioned second dimension.

[0106] Next, with reference to Figure 14, a third example of the first and second sides 50c, 50d of the MR element 50 will be described. Figure 14 is a plan view showing a third example of the first and second sides 50c, 50d of the MR element 50.

[0107] In the third example, the dimension of the first side surface 50c in the cross section intersecting the MR element 50 and perpendicular to the longitudinal direction D3 is smaller than the dimension of the second side surface 50d in the same cross section. Also, the maximum value of dimension Dc1 is smaller than the maximum value of dimension Dd1, and the maximum value of dimension Dc3 is smaller than the maximum value of dimension Dd3. Furthermore, the maximum value of the aforementioned first dimension is smaller than the maximum value of the aforementioned second dimension.

[0108] Note that in Figures 12 to 14, for convenience, the first example of the top surface 50b of the MR element 50 shown in Figure 9 is combined with the first to third examples of the first and second sides 50c and 50d of the MR element 50. However, the second example of the top surface 50b of the MR element 50 shown in Figure 10 or the third example of the top surface 50b of the MR element 50 shown in Figure 11 may also be combined with the first to third examples of the first and second sides 50c and 50d of the MR element 50.

[0109] Next, the operation and effects of the magnetic sensor 1 according to this embodiment will be described. In this embodiment, the MR element 50 includes a first variable portion 501 and a second variable portion 502, each having the characteristics described above. As a result, according to this embodiment, it becomes easier to set the magnetization direction of the free layer 54 in a predetermined direction compared to when the MR element 50 does not include the first variable portion 501 and the second variable portion 502. Specifically, the strength of the magnetic field required to set the magnetization direction of the free layer 54 in a predetermined direction can be reduced. This effect is more effectively exhibited when the coil element 82, when viewed from above, overlaps with at least a portion of each of the first variable portion 501 and the second variable portion 502, as shown in Figure 5.

[0110] [Second Embodiment] Next, with reference to Figure 15, a magnetic sensor 1 according to a second embodiment of the present invention will be described. Figure 15 is a cross-sectional view showing a part of the magnetic sensor 1 according to this embodiment.

[0111] In this embodiment, the overall shape of each of the multiple convex surfaces 305c of the insulating layer 305 is a triangular roof shape formed by moving the triangular shape of the convex surface 305c shown in Figure 15 along a direction parallel to the U direction. Furthermore, each of the multiple first inclined surfaces 305a and the multiple second inclined surfaces 305b of the insulating layer 305 is a plane. Each of the multiple first inclined surfaces 305a is a plane parallel to the U direction and the W1 direction. Each of the multiple second inclined surfaces 305b is a plane parallel to the U direction and the W2 direction.

[0112] The insulating layer 305 may include a plurality of protrusions that form a plurality of convex surfaces 305c, similar to the example shown in Figure 6. Alternatively, the insulating layer 305 may include a plurality of grooves arranged in a direction parallel to the V direction. Each of the plurality of grooves has a first wall surface corresponding to the first inclined surface 305a and a second wall surface corresponding to the second inclined surface 305b. A single convex surface 305c is formed by the first wall surface of one groove and the second wall surface of another groove adjacent to this groove on the -V direction side.

[0113] In the example shown in Figure 15, each of the multiple grooves further has a bottom surface corresponding to the flat surface 305d. However, each of the multiple grooves does not necessarily have to have a bottom surface.

[0114] Other configurations, operations, and effects in this embodiment are the same as those in the first embodiment.

[0115] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are possible. For example, as long as the requirements of the claims are met, the shapes of the upper surface 50b, the first side surface 50c, and the second side surface 50d of the MR element 50 are not limited to the examples shown in each embodiment, but are arbitrary.

[0116] Furthermore, the magnetic sensor 1 may also include a third detection circuit configured to detect a component of the target magnetic field in a direction parallel to the XY plane and to generate at least one third detection signal corresponding to this component. In this case, the processor 40 may be configured to generate a detection value corresponding to the component of the target magnetic field in a direction parallel to the U direction based on at least one third detection signal. The third detection circuit may be integrated with the first and second detection circuits 20, 30, or it may be included in a separate chip from the first and second detection circuits 20, 30.

[0117] As described above, the magnetic sensor of the present invention comprises a substrate having a reference plane, a support member disposed on the substrate and having an inclined surface tilted with respect to the reference plane, and a magnetic detection element disposed on the inclined surface and having a shape that is elongated in one direction. The magnetic detection element has a first side surface and a second side surface located on both sides in the short direction of the magnetic detection element and each having an upper end. The first side surface is located in a direction along the inclined surface and is at the end of a first direction away from the reference plane. The second side surface is located in a direction along the inclined surface and is at the end of a second direction approaching the reference plane. The magnetic detection element includes a first change portion in which at least a portion of the upper end of the first side surface and the upper end of the second side surface are linear and the distance between the upper end of the first side surface and the upper end of the second side surface decreases along the longitudinal direction of the magnetic detection element.

[0118] In the magnetic sensor of the present invention, the magnetic detection element may further have an edge formed by the intersection of a first side surface and a second side surface.

[0119] Furthermore, in the magnetic sensor of the present invention, the upper end of the first side surface in the first change portion may form a first angle with respect to a virtual straight line that extends between the first side surface and the second side surface and is parallel to the longitudinal direction. 2nd The upper end of the side surface may form a second angle with respect to a hypothetical straight line. The first and second angles may be different from each other, or they may be equal.

[0120] Furthermore, in the magnetic sensor of the present invention, each of the first side and the second side may further have a lower end. The lower end of the first side may be located ahead in the first direction when viewed from the upper end of the first side. The lower end of the second side may be located ahead in the second direction when viewed from the upper end of the second side.

[0121] Furthermore, in the magnetic sensor of the present invention, the magnetic detection element may further include a constant portion in which the upper ends of each of the first and second sides along the longitudinal direction are straight and the distance between the first and second sides is constant. An edge may be formed between the upper end of the first change portion and the upper end of the constant portion. The magnetic detection element may further include a second change portion positioned between the first change portion and the constant portion, in which the upper ends of each of the first and second sides along the longitudinal direction are straight and the distance between the first and second sides is small. The second change portion may have a shape symmetrical with respect to the first change portion with respect to a virtual plane that intersects the magnetic detection element and is perpendicular to the longitudinal direction.

[0122] If the magnetic detection element includes a certain portion, the maximum value of the dimension of the first side surface in a first cross section that intersects the first variable portion and is perpendicular to the longitudinal direction may be greater than the maximum value of the dimension of the first side surface in a second cross section that intersects the certain portion and is perpendicular to the longitudinal direction. The maximum value of the dimension of the second side surface in the first cross section may be greater than the maximum value of the dimension of the second side surface in the second cross section. The sum of the maximum value of the dimension of the first side surface in the first cross section that intersects the first variable portion and is perpendicular to the longitudinal direction, and the maximum value of the dimension of the second side surface in the first cross section, may be greater than the sum of the maximum value of the dimension of the first side surface in the second cross section that intersects the certain portion and is perpendicular to the longitudinal direction, and the maximum value of the dimension of the second side surface in the second cross section.

[0123] Furthermore, in the magnetic sensor of the present invention, the first dimension, which is the dimension of the first side surface in a third cross-section that intersects the magnetic detection element and is perpendicular to the longitudinal direction, and the second dimension, which is the dimension of the second side surface in the third cross-section, may be equal to each other. Alternatively, the first dimension, which is the dimension of the first side surface in a third cross-section that intersects the magnetic detection element and is perpendicular to the longitudinal direction, and the second dimension, which is the dimension of the second side surface in the third cross-section, may be different to each other. In this case, the first dimension may be larger than the second dimension. Alternatively, the second dimension may be larger than the first dimension.

[0124] Furthermore, in the magnetic sensor of the present invention, the magnetic detection element may include a plurality of stacked magnetic layers, and the current may be configured to flow in the stacking direction of the plurality of magnetic layers. The plurality of magnetic layers may include a free layer having magnetization whose direction can change in response to an external magnetic field, and a magnetization-fixed layer having magnetization whose direction is fixed and interposed between the free layer and the inclined surface. The magnetic sensor of the present invention may further include a coil that applies a magnetic field in a predetermined direction to the free layer. The coil may overlap at least a portion of the first variable portion when viewed from one direction perpendicular to the reference plane. [Explanation of Symbols]

[0125] 1…Magnetic sensor, 20…First detection circuit, 30…Second detection circuit, 40…Processor, 50…MR element, 50a…Bottom surface, 50b…Top surface, 50b1, 50b2, 50b3…Top surface portion, 50c…First side surface, 50d…Second side surface, 50e1, 50e2…Edge, 50B…First MR element, 50C…Second MR element, 51…Magnetic fixed layer, 52…Gap layer, 53…Free layer, 61, 61B, 61C…Bottom Electrodes, 62, 62B, 62C... Upper electrodes, 80... Coil, 81... Lower coil element, 82... Upper coil element, 100... Magnetic sensor device, 301... Substrate, 301a... Top surface, 302~305, 307~310... Insulating layer, 305a... First inclined surface, 305b... Second inclined surface, 305c... Convex surface, 305d... Flat surface, 305e... Inclined surface, 501... First change portion, 502... Second change portion, 503... Constant portion.

Claims

1. A substrate having a reference plane, A support member is placed on the substrate and has an inclined surface that is inclined with respect to the reference plane, The system comprises a magnetic detection element that is positioned on the inclined surface and has a shape that is elongated in one direction, The magnetic detection element has a first side surface and a second side surface located on both sides in the short direction of the magnetic detection element, each having an upper end. The first side surface is located in a direction along the inclined surface and away from the reference plane, The second side surface is located in a direction along the inclined surface and at the end of the second direction approaching the reference plane, The magnetic detection element includes a first modified portion in which at least a portion of the upper end of the first side surface and the upper end of the second side surface are linear, and the distance between the upper end of the first side surface and the upper end of the second side surface decreases along the longitudinal direction of the magnetic detection element. The upper end of the first side surface in the first modified portion forms a first angle with respect to a hypothetical straight line extending between the first side surface and the second side surface and parallel to the longitudinal direction. The upper end of the second side surface in the first modified portion forms a second angle with respect to the imaginary straight line. A magnetic sensor characterized in that the first angle and the second angle are different from each other.

2. The magnetic sensor according to claim 1, further characterized in that the magnetic detection element has an edge formed by the intersection of the first side surface and the second side surface.

3. Each of the first and second sides further has a lower end, The lower end of the first side surface is located ahead in the first direction when viewed from the upper end of the first side surface, The magnetic sensor according to claim 1, characterized in that the lower end of the second side surface is located ahead in the second direction when viewed from the upper end of the second side surface.

4. The magnetic sensor according to claim 1, further characterized in that the magnetic detection element has upper ends of the first side surface and the second side surface that are straight in line along the longitudinal direction, and the distance between the first side surface and the second side surface includes a constant portion.

5. The magnetic sensor according to claim 4, characterized in that an edge is formed between the upper end of the first variable portion and the upper end of the constant portion.

6. The magnetic sensor according to claim 4, further comprising a second changing portion, which is positioned between the first changing portion and the first changing portion, and wherein the upper ends of the first side surface and the second side surface become straight along the longitudinal direction and the distance between the first side surface and the second side surface becomes smaller.

7. The magnetic sensor according to claim 6, characterized in that the second change portion has a shape symmetric to the first change portion with respect to a virtual plane that intersects the magnetic detection element and is perpendicular to the longitudinal direction.

8. A substrate having a reference plane, A support member is placed on the substrate and has an inclined surface that is inclined with respect to the reference plane, The system comprises a magnetic detection element that is positioned on the inclined surface and has a shape that is elongated in one direction, The magnetic detection element has a first side surface and a second side surface located on both sides in the short direction of the magnetic detection element, each having an upper end. The first side surface is located in a direction along the inclined surface and away from the reference plane, The second side surface is located in a direction along the inclined surface and at the end of the second direction approaching the reference plane, The magnetic detection element includes a first modified portion in which at least a portion of the upper end of the first side surface and the upper end of the second side surface are linear, and the distance between the upper end of the first side surface and the upper end of the second side surface decreases along the longitudinal direction of the magnetic detection element. The magnetic detection element further includes a portion in which the upper ends of the first side surface and the second side surface are straight along the longitudinal direction and the distance between the first side surface and the second side surface is constant. The maximum value of the dimension of the first side surface in the first cross-section that intersects the first change portion and is perpendicular to the longitudinal direction is greater than the maximum value of the dimension of the first side surface in the second cross-section that intersects the constant portion and is perpendicular to the longitudinal direction. A magnetic sensor characterized in that the maximum value of the dimension of the second side surface in the first cross-section is greater than the maximum value of the dimension of the second side surface in the second cross-section.

9. A substrate having a reference plane, A support member is placed on the substrate and has an inclined surface that is inclined with respect to the reference plane, The system comprises a magnetic detection element that is positioned on the inclined surface and has a shape that is elongated in one direction, The magnetic detection element has a first side surface and a second side surface located on both sides in the short direction of the magnetic detection element, each having an upper end. The first side surface is located in a direction along the inclined surface and away from the reference plane, The second side surface is located in a direction along the inclined surface and at the end of the second direction approaching the reference plane, The magnetic detection element includes a first modified portion in which at least a portion of the upper end of the first side surface and the upper end of the second side surface are linear, and the distance between the upper end of the first side surface and the upper end of the second side surface decreases along the longitudinal direction of the magnetic detection element. The magnetic detection element further includes a portion in which the upper ends of the first side surface and the second side surface are straight along the longitudinal direction and the distance between the first side surface and the second side surface is constant. A magnetic sensor characterized in that the sum of the maximum dimension of the first side surface in a first cross-section intersecting the first variable portion and perpendicular to the longitudinal direction, and the maximum dimension of the second side surface in the first cross-section, is greater than the sum of the maximum dimension of the first side surface in a second cross-section intersecting the constant portion and perpendicular to the longitudinal direction, and the maximum dimension of the second side surface in the second cross-section.

10. The magnetic sensor according to claim 1, characterized in that the first dimension, which is the dimension of the first side surface in a third cross-section that intersects the magnetic detection element and is perpendicular to the longitudinal direction, and the second dimension, which is the dimension of the second side surface in the third cross-section, are equal to each other.

11. The magnetic sensor according to claim 1, characterized in that the first dimension, which is the dimension of the first side surface in a third cross-section that intersects the magnetic detection element and is perpendicular to the longitudinal direction, and the second dimension, which is the dimension of the second side surface in the third cross-section, are different from each other.

12. The magnetic sensor according to claim 11, characterized in that the first dimension is larger than the second dimension.

13. The magnetic sensor according to claim 11, characterized in that the second dimension is larger than the first dimension.

14. The magnetic sensor according to any one of claims 1 to 13, characterized in that the magnetic detection element includes a plurality of stacked magnetic layers, and is configured such that an electric current flows in the stacking direction of the plurality of magnetic layers.

15. The magnetic sensor according to claim 14, characterized in that the plurality of magnetic layers include a free layer having magnetization whose direction can change in response to an external magnetic field, and a magnetization-fixed layer having magnetization whose direction is fixed and interposed between the free layer and the inclined surface.

16. Furthermore, the magnetic sensor according to claim 15 is characterized by comprising a coil for applying a magnetic field in a predetermined direction to the free layer.

17. The magnetic sensor according to claim 16, characterized in that the coil overlaps with at least a portion of the first change portion when viewed from one direction perpendicular to the reference plane.

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