Three-axis magnetic sensor

Abstract

A three-axis magnetic sensor, comprising a plurality of magnetic tunnel junctions (140) and a substrate provided with a first slope array (110) and a second slope array (120), wherein the first slope array (110) and the second slope array (120) each comprise a plurality of slope structures (130); the included angle between the orthographic projection of each slope structure (130) of the first slope array (110) in a plane of the substrate and a negative direction of a first axis is equal to the included angle between the orthographic projection of each slope structure (130) of the second slope array (120) in the plane of the substrate and a positive direction of the first axis, each included angle being greater than 0° and less than 90°; the plurality of magnetic tunnel junctions (140) are arranged on each slope structures (130) of the first slope array (110) and the second slope array (120); the pinning direction of the magnetic tunnel junctions (140) located on each first bevel is along the direction of the first bevel, and the pinning direction of the magnetic tunnel junctions (140) located on each second bevel is along the direction of the second bevel; the magnetic tunnel junctions (140) having the same pinning direction are connected in series to form a magnetoresistive unit; and a plurality of magnetoresistive units can form a bridge on the basis of the requirement for superposing or canceling out changes in resistance components, thereby achieving the detection of a three-axis magnetic field.

Description

Three-axis magnetic sensor

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on February 6, 2024, with application number 202410170408.7 and invention name “Three-axis magnetic sensor”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present invention relates to the technical field of magnetic field sensing devices, and in particular to a three-axis magnetic sensor. Background Art

[0003] Magnetic sensors based on magnetic tunnel junctions (MTJs) have the advantages of a large resistance change rate, high sensitivity, low power consumption, good temperature characteristics, and strong anti-interference capabilities. They mainly use the tunnel magnetoresistance (TMR) effect of multilayer magnetic film materials to achieve the effect that the film resistance changes with the magnitude and direction of the external magnetic field. Compared with current anisotropic magnetoresistance (AMR) sensors, tunnel magnetoresistance sensors have a larger resistance change rate and better temperature stability than Hall effect devices. However, the distribution of the external magnetic field is usually three-dimensional, and the TMR magnetoresistance unit can only sense the magnetic field in the plane, which makes it difficult to meet the requirements of measuring three-axis magnetic fields. Summary of the Invention

[0004] According to various embodiments of the present application, a three-axis magnetic sensor is provided.

[0005] A three-axis magnetic sensor includes a plurality of magnetic tunnel junctions and a substrate provided with a first slope array and a second slope array; the first slope array and the second slope array each include a plurality of slope structures, each of the slope structures including a first slope surface and a second slope surface arranged axially symmetrically; the angle between the orthographic projection of each slope structure of the first slope array in the plane of the substrate and the negative direction of the first axis is equal to the angle between the orthographic projection of each slope structure of the second slope array in the plane of the substrate and the positive direction of the first axis, and the angle is greater than 0° and less than 90°; the plurality of magnetic tunnel junctions are provided in the first slope array and the second slope array. On each slope structure, the pinning direction of the magnetic tunnel junction located on the first slope is along the direction of the first slope, and the pinning direction of the magnetic tunnel junction located on the second slope is along the direction of the second slope; the magnetic tunnel junctions with the same pinning direction are connected in series to form a magnetoresistive unit, and the number of magnetic tunnel junctions included in each of the magnetoresistive units is the same, so that the magnetic tunnel junctions located in the first slope array and the second slope array are correspondingly connected in series to form a plurality of magnetoresistive units, and the plurality of magnetoresistive units form an electric bridge for detecting the magnetic fields of the first axis, the second axis and the third axis; wherein the first axis, the second axis and the third axis are perpendicular to each other, and the third axis is also perpendicular to the plane of the substrate.

[0006] The details of one or more embodiments of the present application are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0008] FIG1 is a schematic structural diagram of a three-axis magnetic sensor according to an embodiment;

[0009] FIG2 is a schematic diagram of annealing directions of different regions in one embodiment;

[0010] FIG3 is a schematic cross-sectional view of the slope structure in FIG2 along lines A1-A1', A2-A2', B1-B1', and B2-B2';

[0011] FIG4 is a schematic diagram showing a structure in which magnetoresistive units are connected to form a bridge for performing three-axis magnetic field detection in one embodiment;

[0012] FIG5 is a schematic diagram showing the structure of another embodiment in which magnetoresistive units are connected to form a bridge for performing three-axis magnetic field detection;

[0013] FIG6 is a schematic diagram of annealing directions of different regions in another embodiment;

[0014] FIG7 is a schematic structural diagram of a three-axis magnetic sensor in another embodiment;

[0015] FIG8 is a schematic cross-sectional view of the slope structure along lines AA' and BB' in FIG7 ;

[0016] FIG9 is a schematic diagram showing a structure in which magnetoresistive units are connected to form three types of bridges for performing three-axis magnetic field detection in one embodiment. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0018] In one embodiment, as shown in Figures 1 to 3, a three-axis magnetic sensor is provided, comprising a plurality of magnetic tunnel junctions 140 and a substrate (not shown) provided with a first slope array 110 and a second slope array 120. The first slope array 110 and the second slope array 120 each include a plurality of slope structures 130, each of which includes a first slope surface and a second slope surface arranged symmetrically about an axis. The angle between the orthographic projection of each slope structure 130 in the first slope array 110 and the negative direction of the first axis is equal to the angle between the orthographic projection of each slope structure 130 in the second slope array 120 and the positive direction of the first axis, and the angle is greater than 0° and less than 90°. The plurality of magnetic tunnel junctions 140 are provided on each of the slope structures 130 in the first slope array 110 and the second slope array 120, with the pinning direction of the magnetic tunnel junctions 140 located on the first slope surface being along the first slope surface direction, and the pinning direction of the magnetic tunnel junctions 140 located on the second slope surface being along the second slope surface direction. Magnetic tunnel junctions 140 with the same pinning direction are connected in series to form a magnetoresistive unit, and each magnetoresistive unit includes the same number of magnetic tunnel junctions 140, so that the magnetic tunnel junctions 140 located in the first slope array 110 and the second slope array 120 are connected in series to form a plurality of magnetoresistive units. The plurality of magnetoresistive units form a bridge for detecting magnetic fields along a first axis, a second axis, and a third axis. The first axis, the second axis, and the third axis are perpendicular to each other, and the third axis is also perpendicular to the plane of the substrate.

[0019] Specifically, the setting method of the first axis, the second axis and the third axis is not unique, and can be the X-axis, the Y-axis and the Z-axis respectively, and the plane of the substrate is the XY plane. The slope structure 130 can be a boss or a groove structure. Each slope structure 130 includes a first inclined plane and a second inclined plane arranged axially symmetrically, which means that the slope gradient of the slope structure 130 (the angle between the inclined plane where the magnetic tunnel junction 140 is placed and the plane where the first axis and the second axis are located) is α degrees, and the value of α can be set according to actual needs. The positive projection of each slope structure 130 of the first slope array 110 in the plane of the substrate is at an angle of β degrees to the negative direction of the first axis, and the positive projection of each slope structure 130 of the second slope array 120 in the plane of the substrate is also at an angle of β degrees to the positive direction of the first axis, 0°<β<90°.

[0020] The magnetic tunnel junction 140 includes at least a free layer, a barrier layer, and a pinned layer. Changes in the ambient magnetic field can cause the magnetization direction of the free layer to change. When the magnetization direction of the free layer is positively parallel to the pinning direction of the pinned layer, the magnetic tunnel junction 140 is in a low-resistance state. When the magnetization direction of the free layer is antiparallel to the pinning direction of the pinned layer, the magnetic tunnel junction 140 is in a high-resistance state. Thus, the magnetic field component of the external magnetic field parallel to the pinning direction can cause the magnetization direction of the free layer to change, and this parallel state with the pinning direction of the pinned layer can cause the resistance of the magnetic tunnel junction 140 to change. By forming a bridge with magnetoresistive units formed by connecting the magnetic tunnel junctions 140 in series, an electrical signal corresponding to the component of the external magnetic field in the pinning direction can be output.

[0021] By setting the pinning directions of the multiple magnetic tunnel junctions 140 along the slope direction of the slope structure 130, the pinning directions of the multiple magnetic tunnel junctions 140 have a component along the Z-axis direction, and thus can sense a magnetic field in the Z-axis direction. Because the slope structures 130 with the same slope gradient are used, the components of the pinning directions of the multiple magnetic tunnel junctions 140 in the Z-axis direction are equal and in the same or opposite directions. Furthermore, the multiple slope structures 130 are set so that their orthographic projections in the plane of the substrate have an angle with the positive direction of the X-axis (or with the negative direction of the X-axis), and the angle is greater than 0° and less than 90°, so that the orthographic projections of the pinning directions of the multiple magnetic tunnel junctions 140 in the plane of the substrate (i.e., the orthographic projections in the XY plane) have a component along the X-axis direction and a component along the Y-axis direction. As a result, the multiple magnetic tunnel junctions 140 can sense a magnetic field in the X-axis direction and a magnetic field in the Y-axis direction. By setting the angle between the orthogonal projections of the multiple slope structures 130 of the first slope array 110 within the plane of the substrate and the negative X-axis direction and the angle between the orthogonal projections of the multiple slope structures 130 of the second slope array 120 within the plane of the substrate and the positive X-axis direction to be equal, and by setting the first slope and the second slope to be axisymmetric, the components of the pinning directions of the multiple magnetic tunnel junctions 140 in the X-axis, Y-axis, and Z-axis directions are equal and in the same or opposite directions. In this way, the magnetic tunnel junctions 140 with the same pinning direction are connected in series to form a magnetoresistive unit, and each magnetoresistive unit includes the same number of magnetic tunnel junctions 140. The magnetic tunnel junctions 140 in the first slope array 110 and the second slope array 120 are connected in series to form multiple magnetoresistive units. Each magnetoresistive unit will produce a change in resistance based on changes in the external magnetic field, and the components of the resistance change in the X-axis, Y-axis, and Z-axis directions are equal and in the same or opposite directions. Based on the need to superimpose or offset the changes in resistance components, multiple magnetoresistive units can be used to form an electric bridge, thereby realizing the detection of a three-axis magnetic field.

[0022] In one embodiment, as shown in FIG2 , both the first and second inclined surfaces extend along the central axis H of the slope structure 130, allowing for the arrangement of as many magnetic tunnel junctions 140 as possible. The slope structures 130 in the first and second slope arrays 110 and 120 are arranged in a direction perpendicular to the central axis H of the slope structures 130 within the plane of the substrate. It should be understood that the angle between the orthographic projection of the multiple slope structures 130 of the first slope array 110 within the plane of the substrate and the negative direction of the X-axis refers to the angle between the orthographic projection of the central axis H of the multiple slope structures 130 of the first slope array 110 within the plane of the substrate and the negative direction of the X-axis. Similarly, the angle between the orthographic projection of the multiple slope structures 130 of the second slope array 120 within the plane of the substrate and the positive direction of the X-axis refers to the angle between the orthographic projection of the central axis H of the multiple slope structures 130 of the second slope array 120 within the plane of the substrate and the positive direction of the X-axis.

[0023] In one embodiment, the number of slope structures 130, the geometric dimensions of the slope structures 130, the number of magnetic tunnel junctions 140, and the geometric dimensions of the magnetic tunnel junctions 140 in the first slope array 110 and the second slope array 120 are all identical. Setting the geometric dimensions of the slope structures 130 / magnetic tunnel junctions 140 in the first slope array 110 and the second slope array 120 to be identical can mean that the geometric dimensions are exactly the same, or that the error in the geometric dimensions is within an allowable range. By designing the number and geometric dimensions of the slope structures 130 and the magnetic tunnel junctions 140 in the first slope array 110 and the second slope array 120 to be identical, the fabrication of the slope structures 130 and the magnetic tunnel junctions 140, as well as the series connection and bridge formation of the magnetic tunnel junctions 140, can be facilitated, and magnetic field detection can be more accurately performed.

[0024] In one embodiment, the pinning direction of the magnetic tunnel junction 140 located on the first slope of the slope structure 130 is upward along the first slope, and the pinning direction of the magnetic tunnel junction 140 located on the second slope of the slope structure 130 is downward along the second slope; alternatively, the pinning direction of the magnetic tunnel junction 140 located on the first slope of the slope structure 130 is downward along the first slope, and the pinning direction of the magnetic tunnel junction 140 located on the second slope of the slope structure 130 is upward along the second slope.

[0025] The pinning direction of the magnetic tunnel junction 140 can be determined by the annealing magnetic field. As shown in FIG2 , the black arrow indicates the in-plane annealing direction. For the magnetic tunnel junctions 140 of the same slope structure 130 , annealing can be performed in the plane of the substrate in a direction perpendicular to the central axis H of the slope structure 130, so that the pinning direction of the magnetic tunnel junction 140 on the first slope is upward along the first slope, and the pinning direction of the magnetic tunnel junction 140 on the second slope is downward along the second slope; or alternatively, the pinning direction of the magnetic tunnel junction 140 on the first slope is downward along the first slope, and the pinning direction of the magnetic tunnel junction 140 on the second slope is upward along the second slope.

[0026] Specifically, the first slope array 110 is divided into a first region 11 and a second region 12, and the second slope array 120 is divided into a third region 13 and a fourth region 14. The pinning direction of the magnetic tunnel junctions 140 on the slope structures 130 in the first and third regions 11 and 13 is such that the magnetic tunnel junctions 140 located on the first slope face are upward along the first slope face, and the magnetic tunnel junctions 140 located on the second slope face are downward along the second slope face. The pinning direction of the magnetic tunnel junctions 140 on the slope structures 130 in the second and fourth regions 12 and 14 is such that the magnetic tunnel junctions 140 located on the first slope face are downward along the first slope face, and the magnetic tunnel junctions 140 located on the second slope face are upward along the second slope face. As shown in Figures 2 and 3, taking the slope structure 130 as a platform as an example, the first and third regions 11 and 13 are annealed perpendicular to the central axis H of the slope structure 130, and from the first slope face W1 to the second slope face W2 of the slope structure 130. The second region 12 and the fourth region 14 are annealed perpendicular to the central axis H of the slope structure 130 and from the second inclined surface W2 toward the first inclined surface W1 of the slope structure 130. It will be appreciated that if the slope structure 130 is designed as a groove, the annealing is also performed perpendicular to the central axis H of the slope structure 130, but in the opposite direction along the inclined surface of the slope structure 130. For example, with respect to the first region 11, when the slope structure 130 is designed as a groove, the annealing is performed perpendicular to the central axis H of the slope structure 130 and from the second inclined surface toward the first inclined surface of the slope structure 130. This ensures that the pinning directions of the magnetic tunnel junctions 140 on the slope structure 130 are such that the magnetic tunnel junctions 140 located on the first inclined surface are upward along the first inclined surface, and the magnetic tunnel junctions 140 located on the second inclined surface are downward along the second inclined surface.

[0027] 2 and 3 , also taking the slope structure 130 designed as a boss as an example, the pinning directions of the magnetic tunnel junctions 140 on the slope structures 130 in the first region 11 and the third region 13 are that the magnetic tunnel junctions 140 located on the first slope W1 are upward along the first slope W1, and the magnetic tunnel junctions 140 located on the second slope W2 are downward along the second slope W2; the pinning directions of the magnetic tunnel junctions 140 on the slope structures 130 in the second region 12 and the fourth region 14 are that the magnetic tunnel junctions 140 located on the first slope W1 are downward along the first slope W1, and the magnetic tunnel junctions 140 located on the second slope W2 are upward along the second slope W2. Thus, the pinning directions of the magnetic tunnel junctions 140 on the first inclined surface W1 and the second inclined surface W2 of the slope structure 130 in the first region 11 and the fourth region 14 all have a component along the positive direction of the X-axis, while the pinning directions of the magnetic tunnel junctions 140 on the first inclined surface W1 and the second inclined surface W2 of the slope structure 130 in the second region 12 and the third region 13 all have a component along the negative direction of the X-axis. The pinning directions of the magnetic tunnel junctions 140 on the first inclined surface W1 and the second inclined surface W2 of the slope structure 130 in the first region 11 and the third region 13 all have a component along the positive direction of the Y-axis, while the pinning directions of the magnetic tunnel junctions 140 on the first inclined surface W1 and the second inclined surface W2 of the slope structure 130 in the second region 12 and the fourth region 14 all have a component along the negative direction of the Y-axis. The pinning directions of the magnetic tunnel junctions 140 located on the first slope W1 of the slope structure 130 in the first region 11 and the third region 13 and the magnetic tunnel junctions 140 located on the second slope W2 of the slope structure 130 in the second region 12 and the fourth region 14 both have components along the positive direction of the Z axis. The pinning directions of the magnetic tunnel junctions 140 located on the second slope W2 of the slope structure 130 in the first region 11 and the third region 13 and the magnetic tunnel junctions 140 located on the first slope W1 of the slope structure 130 in the second region 12 and the fourth region 14 both have components along the negative direction of the Z axis.

[0028] The magnetic tunnel junctions 140 on the first slope surface of the slope structure 130 in the first region 11 are connected in series to form a magnetoresistive unit R11; the magnetic tunnel junctions 140 on the second slope surface of the slope structure 130 in the first region 11 are connected in series to form a magnetoresistive unit R12; the magnetic tunnel junctions 140 on the first slope surface of the slope structure 130 in the second region 12 are connected in series to form a magnetoresistive unit R14; and the magnetic tunnel junctions 140 on the second slope surface of the slope structure 130 in the second region 12 are connected in series to form a magnetoresistive unit R13. The magnetic tunnel junctions 140 on the first slope surface of the slope structure 130 in the third region 13 are connected in series to form a magnetoresistive unit R21; the magnetic tunnel junctions 140 on the second slope surface of the slope structure 130 in the third region 13 are connected in series to form a magnetoresistive unit R22; the magnetic tunnel junctions 140 on the first slope surface of the slope structure 130 in the fourth region 14 are connected in series to form a magnetoresistive unit R24; and the magnetic tunnel junctions 140 on the second slope surface of the slope structure 130 in the fourth region 14 are connected in series to form a magnetoresistive unit R23.

[0029] As shown in Figures 2 and 3, taking the ramp structure 130 as an example, the pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R11 on the three axes are +X, +Y, and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R12 on the three axes are +X, +Y, and -Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R13 on the three axes are -X, -Y, and +Z, respectively. And the pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R14 on the three axes are -X, -Y, and -Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R21 on the three axes are -X, +Y, and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R22 on the three axes are -X, +Y, and -Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R23 on three axes are +X, -Y, and +Z. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R24 on three axes are +X, -Y, and -Z.

[0030] In one embodiment, four slope structures 130 are provided in each of the first region 11, the second region 12, the third region 13, and the fourth region 14. Two magnetoresistive units R11 and two magnetoresistive units R12 may be formed in the first region 11. That is, the first region 11 includes four first slopes and four second slopes. The magnetic tunnel junctions 140 on every two first slopes are connected in series to form a magnetoresistive unit R11, and the magnetic tunnel junctions 140 on every two second slopes are connected in series to form a magnetoresistive unit R12. Similarly, two magnetoresistive units R13 and two magnetoresistive units R14 may be formed in the second region 12, two magnetoresistive units R21 and two magnetoresistive units R22 may be formed in the third region 13, and two magnetoresistive units R23 and two magnetoresistive units R24 may be formed in the fourth region 14. It will be appreciated that the number of slope structures 130 in each region and the number of magnetic tunnel junctions 140 in each magnetoresistive unit can be designed based on actual conditions and are not limited herein.

[0031] In one embodiment, the magnetoresistance units R11 , R14 , R22 , and R23 form a first bridge, and the magnetoresistance units R12 , R13 , R21 , and R24 form a second bridge.

[0032] Specifically, as shown in Figure 4, two magnetoresistance units R11, two magnetoresistance units R14, two magnetoresistance units R22 and two magnetoresistance units R23 can be selected, one magnetoresistance unit R11 is connected to terminal A1 and terminal B1, one magnetoresistance unit R11 is connected to terminal E1 and terminal F1, one magnetoresistance unit R14 is connected to terminal C1 and terminal D1, one magnetoresistance unit R14 is connected to terminal G1 and terminal H1, one magnetoresistance unit R22 is connected to terminal E1 and terminal D1, one magnetoresistance unit R22 is connected to terminal A1 and terminal H1, one magnetoresistance unit R23 is connected to terminal B1 and terminal C1, and one magnetoresistance unit R23 is connected to terminal G1 and terminal F1, thereby forming a first bridge. The first bridge has two output modes. When terminal A1 is connected to the power supply terminal Vcc and terminal E1 is connected to the ground terminal Gnd, terminal G1 and terminal C1 output a first output signal. When terminal B1 is connected to the power supply terminal Vcc and terminal F1 is connected to the ground terminal Gnd, terminal D1 and terminal H1 output a second output signal.

[0033] It is understandable that in other embodiments, the terminals connected to the power terminal Vcc and the ground terminal Gnd can be interchanged. For example, for the first output mode of the first bridge, the terminal A1 can be connected to the ground terminal Gnd, and the terminal E1 can be connected to the power terminal Vcc.

[0034] Two magnetoresistive units R12, two magnetoresistive units R13, two magnetoresistive units R21, and two magnetoresistive units R24 are selected, with one magnetoresistive unit R12 connected to terminal A2 and terminal B2, one magnetoresistive unit R12 connected to terminal E2 and terminal F2, one magnetoresistive unit R13 connected to terminal C2 and terminal D2, one magnetoresistive unit R13 connected to terminal G2 and terminal H2, one magnetoresistive unit R21 connected to terminal E2 and terminal D2, one magnetoresistive unit R21 connected to terminal A2 and terminal H2, one magnetoresistive unit R24 connected to terminal B2 and terminal C2, and one magnetoresistive unit R24 connected to terminal G2 and terminal F2, thereby forming a second bridge. The second bridge has two output modes: when terminal A2 is connected to the power supply terminal Vcc and terminal E2 is connected to the ground terminal Gnd, terminals G2 and C2 output a first output signal; when terminal B2 is connected to the power supply terminal Vcc and terminal F2 is connected to the ground terminal Gnd, terminals D2 and terminal H2 output a second output signal.

[0035] As shown in FIG4 , taking the ramp structure 130 using a boss as an example, for the first bridge, when terminal A1 is connected to the power supply terminal Vcc, terminal E1 is connected to the ground terminal Gnd, and terminals G1 and C1 output the first output signal, an adjacent magnetoresistive unit R11 and a magnetoresistive unit R23 form one bridge arm, and another adjacent magnetoresistive unit R11 and another magnetoresistive unit R23 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis direction are offset, and the components in the X-axis direction are all along the positive direction of the X-axis, and the components in the Z-axis direction are all along the positive direction of the Z-axis; an adjacent magnetoresistive unit R14 and a magnetoresistive unit R22 form one bridge arm, and another adjacent magnetoresistive unit R14 and another magnetoresistive unit R22 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis direction are offset, and the components in the X-axis direction are all along the negative direction of the X-axis, and the components in the Z-axis direction are all along the negative direction of the Z-axis. Thus, in this output mode, the first output signal corresponds to the X-axis magnetic field and the Z-axis magnetic field. When terminal B1 is connected to the power supply terminal Vcc, terminal F1 is connected to the ground terminal Gnd, and terminal D1 and terminal H1 output the second output signal, an adjacent magnetoresistance unit R11 and a magnetoresistance unit R22 form a bridge arm, and another adjacent magnetoresistance unit R11 and another magnetoresistance unit R22 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis and Z-axis directions are offset respectively, and the components in the Y-axis direction are all along the positive direction of the Y-axis. An adjacent magnetoresistance unit R14 and a magnetoresistance unit R23 form a bridge arm, and another adjacent magnetoresistance unit R14 and another magnetoresistance unit R23 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis and Z-axis directions are offset respectively, and the components in the Y-axis direction are all along the negative direction of the Y-axis. In this way, in this output mode, the second output signal corresponds to the Y-axis magnetic field.

[0036] For the second bridge, when terminal A2 is connected to the power supply terminal Vcc, terminal E2 is connected to the ground terminal Gnd, and terminals G2 and C2 output the first output signal, an adjacent magnetoresistive unit R12 and a magnetoresistive unit R24 form a bridge arm, and another adjacent magnetoresistive unit R12 and another magnetoresistive unit R24 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis direction are offset, the components in the X-axis direction are all along the positive direction of the X-axis, and the components in the Z-axis direction are all along the negative direction of the Z-axis; an adjacent magnetoresistive unit R13 and a magnetoresistive unit R21 form a bridge arm, and another adjacent magnetoresistive unit R13 and another magnetoresistive unit R21 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis direction are offset, the components in the X-axis direction are all along the negative direction of the X-axis, and the components in the Z-axis direction are all along the positive direction of the Z-axis. In this way, in this output mode, the first output signal corresponds to the X-axis magnetic field and the -Z-axis magnetic field. When terminal B2 is connected to the power supply terminal Vcc, terminal F2 is connected to the ground terminal Gnd, and terminal D2 and terminal H2 output the second output signal, an adjacent magnetoresistive unit R12 and a magnetoresistive unit R21 form a bridge arm, and another adjacent magnetoresistive unit R12 and another magnetoresistive unit R21 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis and Z-axis directions are offset respectively, and the components in the Y-axis direction are all along the positive direction of the Y-axis. An adjacent magnetoresistive unit R13 and a magnetoresistive unit R24 form a bridge arm, and another adjacent magnetoresistive unit R13 and another magnetoresistive unit R24 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis and Z-axis directions are offset respectively, and the components in the Y-axis direction are all along the negative direction of the Y-axis. In this way, in this output mode, the second output signal corresponds to the Y-axis magnetic field.

[0037] It can be seen that the first output signal of the first bridge and the first output signal of the second bridge can be added or subtracted to correspond to the X-axis and Z-axis magnetic fields respectively; the second output signal of the first bridge or the second output signal of the second bridge or the second output signal of the first bridge and the second output signal of the second bridge can be added to correspond to the Y-axis magnetic field, that is, the detection of three-axis magnetic fields can be achieved through the first bridge and the second bridge.

[0038] In one embodiment, the magnetoresistance units R11 , R14 , R21 , and R24 constitute a third bridge, and the magnetoresistance units R12 , R13 , R22 , and R23 constitute a fourth bridge.

[0039] Specifically, as shown in Figure 5, two magnetoresistance units R11, two magnetoresistance units R14, two magnetoresistance units R21 and two magnetoresistance units R24 can be selected, one magnetoresistance unit R11 is connected to terminal A3 and terminal B3, one magnetoresistance unit R11 is connected to terminal E3 and terminal F3, one magnetoresistance unit R14 is connected to terminal C3 and terminal D3, one magnetoresistance unit R14 is connected to terminal G3 and terminal H3, one magnetoresistance unit R24 is connected to terminal E3 and terminal D3, one magnetoresistance unit R24 is connected to terminal A3 and terminal H3, one magnetoresistance unit R21 is connected to terminal B3 and terminal C3, and one magnetoresistance unit R21 is connected to terminal G3 and terminal F3, thereby forming a third bridge. The third bridge has two output modes. When terminal A3 is connected to the power supply terminal Vcc and terminal E3 is connected to the ground terminal Gnd, terminal G3 and terminal C3 output a first output signal. When terminal B3 is connected to the power supply terminal Vcc and terminal F3 is connected to the ground terminal Gnd, terminal D3 and terminal H3 output a second output signal.

[0040] Two magnetoresistive units R12, two magnetoresistive units R13, two magnetoresistive units R22, and two magnetoresistive units R23 are selected. One magnetoresistive unit R12 is connected to terminal A4 and terminal B4, one magnetoresistive unit R12 is connected to terminal E4 and terminal F4, one magnetoresistive unit R13 is connected to terminal C4 and terminal D4, one magnetoresistive unit R13 is connected to terminal G4 and terminal H4, one magnetoresistive unit R23 is connected to terminal E4 and terminal D4, one magnetoresistive unit R23 is connected to terminal A4 and terminal H4, one magnetoresistive unit R22 is connected to terminal B4 and terminal C4, and one magnetoresistive unit R22 is connected to terminal G4 and terminal F4, thereby forming a fourth bridge. The fourth bridge has two output modes. When terminal A4 is connected to the power supply terminal Vcc and terminal E4 is connected to the ground terminal Gnd, terminals G4 and C4 output a first output signal. When terminal B4 is connected to the power supply terminal Vcc and terminal F4 is connected to the ground terminal Gnd, terminals D4 and terminal H4 output a second output signal.

[0041] As shown in FIG5 , taking the ramp structure 130 as a boss as an example, for the third bridge, when terminal A3 is connected to the power supply terminal Vcc, terminal E3 is connected to the ground terminal Gnd, and terminals G3 and C3 output the first output signal, adjacent magnetoresistive units R11 and R21 form one bridge arm, and another adjacent magnetoresistive unit R11 and R21 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis direction are offset, and the components in the Y-axis direction are all in the positive Y-axis direction, and the components in the Z-axis direction are all in the positive Z-axis direction. Adjacent magnetoresistive units R14 and R24 form one bridge arm, and another adjacent magnetoresistive unit R14 and R24 form another bridge arm. In each bridge arm, the components of the pinning direction in the X-axis direction are offset, and the components in the Y-axis direction are all in the negative Y-axis direction, and the components in the Z-axis direction are all in the negative Z-axis direction. Thus, in this output mode, the first output signal corresponds to the Y-axis magnetic field and the Z-axis magnetic field. When terminal B3 is connected to the power supply terminal Vcc, terminal F3 is connected to the ground terminal Gnd, and terminals D3 and H3 output the second output signal, adjacent magnetoresistive units R11 and R24 form one bridge arm, and another adjacent magnetoresistive unit R11 and R24 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis and Z-axis directions cancel each other, and the component in the X-axis direction is along the positive X-axis direction. Adjacent magnetoresistive units R14 and R21 form one bridge arm, and another adjacent magnetoresistive unit R14 and R21 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis and Z-axis directions cancel each other, and the component in the X-axis direction is along the negative X-axis direction. Thus, in this output mode, the second output signal corresponds to the X-axis magnetic field.

[0042] For the fourth bridge, when terminal A4 is connected to the power supply terminal Vcc, terminal E4 is connected to the ground terminal Gnd, and terminals G4 and C4 output the first output signal, adjacent magnetoresistive units R12 and R22 form one bridge arm, and another adjacent magnetoresistive unit R12 and R22 form another bridge arm. In each bridge arm, the pinning direction components in the X-axis direction cancel each other, the Y-axis components are all in the positive Y-axis direction, and the Z-axis components are all in the negative Z-axis direction. Adjacent magnetoresistive units R13 and R23 form one bridge arm, and another adjacent magnetoresistive unit R13 and R23 form another bridge arm. In each bridge arm, the pinning direction components in the X-axis direction cancel each other, the Y-axis components are all in the negative Y-axis direction, and the Z-axis components are all in the positive Z-axis direction. Thus, in this output mode, the first output signal corresponds to the Y-axis magnetic field and the -Z-axis magnetic field. When terminal B4 is connected to the power supply terminal Vcc, terminal F4 is connected to the ground terminal Gnd, and terminal D4 and terminal H4 output the second output signal, an adjacent magnetoresistance unit R12 and a magnetoresistance unit R23 form a bridge arm, and another adjacent magnetoresistance unit R12 and another magnetoresistance unit R23 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis and Z-axis directions are offset respectively, and the components in the X-axis direction are all along the positive direction of the X-axis. An adjacent magnetoresistance unit R13 and a magnetoresistance unit R22 form a bridge arm, and another adjacent magnetoresistance unit R13 and another magnetoresistance unit R22 form another bridge arm. In each bridge arm, the components of the pinning direction in the Y-axis and Z-axis directions are offset respectively, and the components in the X-axis direction are all along the negative direction of the X-axis. In this way, in this output mode, the second output signal corresponds to the X-axis magnetic field.

[0043] It can be seen that after adding or subtracting the first output signal of the third bridge and the first output signal of the fourth bridge, they can correspond to the Y-axis and Z-axis magnetic fields respectively; after adding the second output signal of the third bridge or the second output signal of the fourth bridge or the second output signal of the third bridge and the second output signal of the fourth bridge, they can correspond to the X-axis magnetic field, that is, the detection of three-axis magnetic fields can be realized through the third bridge and the fourth bridge.

[0044] In one embodiment, the pinning directions of the magnetic tunnel junctions 140 located on the first and second slopes of the slope structure 130 are both upward along the slopes, or the pinning directions of the magnetic tunnel junctions 140 located on the first and second slopes of the slope structure 130 are both downward along the slopes.

[0045] The pinning direction of the magnetic tunnel junction 140 can be determined by the annealing magnetic field. As shown in Figure 6, the black arrow indicates the out-of-plane annealing direction. For the same slope structure 130, annealing is performed in a direction perpendicular to the substrate plane (i.e., along the Z-axis), so that the pinning directions of the magnetic tunnel junctions 140 located on the first and second slopes are both upward or downward along the slope.

[0046] Specifically, the pinning direction of the magnetic tunnel junctions 140 on the slope structures 130 in the first slope array 110 is upward along the slope surface, while the pinning direction of the magnetic tunnel junctions 140 on the slope structures 130 in the second slope array 120 is downward along the slope surface. Taking the example of a slope structure 130 designed as a boss, the magnetic tunnel junctions 140 on the slope structures 130 in the first slope array 110 are annealed in a direction perpendicular to the substrate plane and upward; while the magnetic tunnel junctions 140 on the slope structures 130 in the second slope array 120 are annealed in a direction perpendicular to the substrate plane and downward. It will be understood that if the slope structures 130 are designed as grooves, the magnetic tunnel junctions 140 on the slope structures 130 in the first slope array 110 are still annealed in a direction perpendicular to the substrate plane and upward; while the magnetic tunnel junctions 140 on the slope structures 130 in the second slope array 120 are still annealed in a direction perpendicular to the substrate plane and downward.

[0047] 7 and 8 , again taking the example of the slope structure 130 being designed as a boss, the pinning directions of the magnetic tunnel junctions 140 on the slope structures 130 in the first slope array 110 are all upward along the slope, while the pinning directions of the magnetic tunnel junctions 140 on the slope structures 130 in the second slope array 120 are all downward along the slope. Thus, in the first slope array 110, the pinning directions of the magnetic tunnel junctions 140 on the first slope of the slope structure 130 have components along the positive X-axis, the positive Y-axis, and the positive Z-axis, while the pinning directions of the magnetic tunnel junctions 140 on the second slope of the slope structure 130 have components along the negative X-axis, the negative Y-axis, and the positive Z-axis. In the second slope array 120, the pinning direction of the magnetic tunnel junction 140 on the first slope of the slope structure 130 has a component along the negative direction of the X axis, a component along the positive direction of the Y axis, and a component along the negative direction of the Z axis. The pinning direction of the magnetic tunnel junction 140 on the second slope of the slope structure 130 has a component along the positive direction of the X axis, a component along the negative direction of the Y axis, and a component along the negative direction of the Z axis.

[0048] The magnetic tunnel junctions 140 on the first sloped surface of the slope structures 130 of the first slope array 110 are connected in series to form a magnetoresistive unit R15. The magnetic tunnel junctions 140 on the second sloped surface of the slope structures 130 of the first slope array 110 are connected in series to form a magnetoresistive unit R16. The magnetic tunnel junctions 140 on the first sloped surface of the slope structures 130 of the second slope array 120 are connected in series to form a magnetoresistive unit R25. The magnetic tunnel junctions 140 on the second sloped surface of the slope structures 130 of the second slope array 120 are connected in series to form a magnetoresistive unit R26.

[0049] As shown in Figures 7 and 8, taking the ramp structure 130 as an example, the pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R15 on the three axes are +X, +Y, and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R16 on the three axes are -X, -Y, and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R25 on the three axes are -X, +Y, and -Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R26 on the three axes are +X, -Y, and -Z, respectively.

[0050] In one embodiment, the magnetoresistive unit R15 , the magnetoresistive unit R16 , the magnetoresistive unit R25 , and the magnetoresistive unit R26 are connected to form three types of bridges, respectively, for detecting magnetic fields in corresponding axial directions.

[0051] As shown in Figure 9, two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 are selected to form a Z-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply terminal Vcc and is connected to the terminal A5 through one magnetoresistance unit R16, and another magnetoresistance unit R15 is connected to the ground terminal GND and is connected to the terminal B5 through another magnetoresistance unit R16; one magnetoresistance unit R25 is connected to the terminal A5 and is connected to the ground terminal GND through one magnetoresistance unit R26, and another magnetoresistance unit R25 is connected to the terminal B5 and is connected to the power supply terminal Vcc through another magnetoresistance unit R26. Adjacent magnetoresistive units R15 and R16 form one bridge arm, and another adjacent magnetoresistive unit R15 and R16 form another bridge arm. In each bridge arm, the components of the pinning direction in the X and Y axes are offset, and the component in the Z axis is along the positive Z axis. Adjacent magnetoresistive units R25 and R26 form one bridge arm, and another adjacent magnetoresistive unit R25 and R26 form another bridge arm. In each bridge arm, the components of the pinning direction in the X and Y axes are offset, and the component in the Z axis is along the negative Z axis. The output signals of terminals A5 and B5 of the Z-axis sensing bridge contain only the induced component of the Z-axis magnetic field.

[0052] Furthermore, two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 are selected to form an X-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply terminal Vcc and is connected to the terminal A6 through a magnetoresistance unit R26, another magnetoresistance unit R15 is connected to the terminal B6 and is connected to the ground terminal GND through another magnetoresistance unit R26; one magnetoresistance unit R25 is connected to the ground terminal GND and is connected to the terminal A6 through a magnetoresistance unit R16, another magnetoresistance unit R25 is connected to the terminal B6 and is connected to the power supply terminal Vcc through another magnetoresistance unit R16. Adjacent magnetoresistive units R15 and R26 form one bridge arm, and another adjacent magnetoresistive unit R15 and R26 form another bridge arm. In each bridge arm, the components of the pinning direction in the Z and Y axes are offset, and the component in the X axis is along the positive X axis. Adjacent magnetoresistive units R25 and R16 form one bridge arm, and another adjacent magnetoresistive unit R25 and R16 form another bridge arm. In each bridge arm, the components of the pinning direction in the Z and Y axes are offset, and the component in the X axis is along the negative X axis. The output signals of terminals A6 and B6 of the X-axis sensing bridge contain only the inductive component of the X-axis magnetic field.

[0053] Furthermore, two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 can be selected to form a Y-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply terminal Vcc and is connected to terminal A7 through one magnetoresistance unit R25, another magnetoresistance unit R15 is connected to terminal B7 and is connected to the ground terminal GND through another magnetoresistance unit R25; one magnetoresistance unit R26 is connected to the ground terminal GND and is connected to terminal A7 through one magnetoresistance unit R16, another magnetoresistance unit R26 is connected to terminal B7 and is connected to the power supply terminal Vcc through another magnetoresistance unit R16. Adjacent magnetoresistive units R15 and R25 form one bridge arm, and another adjacent magnetoresistive unit R15 and another magnetoresistive unit R25 form another bridge arm. In each bridge arm, the components of the pinning direction in the Z and X axes cancel each other out, while the component in the Y axis lies along the positive Y axis. Adjacent magnetoresistive units R26 and R16 form one bridge arm, and another adjacent magnetoresistive unit R26 and another magnetoresistive unit R16 form another bridge arm. In each bridge arm, the components of the pinning direction in the Z and X axes cancel each other out, while the component in the Y axis lies along the negative Y axis. The output signals from terminals A7 and B7 of the Y-axis sensing bridge contain only the inductive component of the Y-axis magnetic field.

[0054] Through the above three bridges, the magnetic fields in the X-axis, Y-axis and Z-axis directions can be detected separately, simplifying the subsequent signal processing circuit.

[0055] The X-axis sensing bridge, Y-axis sensing bridge, and Z-axis sensing bridge all include two magnetoresistive units R15, two magnetoresistive units R16, two magnetoresistive units R25, and two magnetoresistive units R26. However, the magnetoresistive units are connected differently to each other, and to the power supply terminal Vcc, ground terminal GND, and signal output terminal. Based on the specific connection method, three independent bridges can be configured. Alternatively, a switching circuit can be provided to switch between three modes. In different modes, the magnetoresistive units are connected to form different bridges.

[0056] In one embodiment, the three-axis magnetic sensor can be configured as a dual chip, with the first ramp array 110 disposed on the first chip and the second ramp array 120 disposed on the second chip. After annealing each magnetic tunnel junction 140, the first and second chips are packaged together. The first and second chips are both disposed on a substrate and can be electrically connected through the substrate. The substrate can include an ASIC circuit that can process the analog signals output by the first and / or second chips into digital signals and can also output the processed digital signals. By designing the connection method of the magnetic tunnel junctions 140 of the two chips with different pinning directions, combined with the signal processing of the substrate, three-axis magnetic field sensing of the X-axis, Y-axis, and Z-axis can be achieved.

[0057] It is understood that in other embodiments, the three-axis magnetic sensor may also be provided in the form of a single chip, that is, the first slope array 110 and the second slope array 120 are provided on the same chip.

[0058] It can be understood that in other embodiments, the substrate may also be a silicon substrate.

[0059] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A three-axis magnetic sensor, characterized in that: The invention relates to a substrate comprising a plurality of magnetic tunnel junctions and a first slope array and a second slope array; the first slope array and the second slope array each comprise a plurality of slope structures, each of the slope structures comprising a first slope surface and a second slope surface symmetrically arranged about an axis; the angle between the positive projection of each slope structure of the first slope array in the plane of the substrate and the negative direction of the first axis is equal to the angle between the positive projection of each slope structure of the second slope array in the plane of the substrate and the positive direction of the first axis, and the angle is greater than 0° and less than 90°; the plurality of magnetic tunnel junctions are arranged at each slope junction of the first slope array and the second slope array. The structure is such that the pinning direction of the magnetic tunnel junction located on the first slope is along the direction of the first slope, and the pinning direction of the magnetic tunnel junction located on the second slope is along the direction of the second slope; the magnetic tunnel junctions with the same pinning direction are connected in series to form a magnetoresistive unit, and each of the magnetoresistive units includes the same number of magnetic tunnel junctions, so that the magnetic tunnel junctions located on the first slope array and the second slope array are connected in series to form a plurality of magnetoresistive units, and the plurality of magnetoresistive units form an electric bridge for detecting the magnetic fields of the first axis, the second axis and the third axis; wherein the first axis, the second axis and the third axis are perpendicular to each other, and the third axis is also perpendicular to the plane of the substrate.

2. The three-axis magnetic sensor according to claim 1, wherein: The pinning direction of the magnetic tunnel junction located on the first slope of the slope structure is upward along the first slope, and the pinning direction of the magnetic tunnel junction located on the second slope of the slope structure is downward along the second slope; or, the pinning direction of the magnetic tunnel junction located on the first slope of the slope structure is downward along the first slope, and the pinning direction of the magnetic tunnel junction located on the second slope of the slope structure is upward along the second slope.

3. The three-axis magnetic sensor according to claim 2, wherein: The first slope array is divided into a first area and a second area, and the second slope array is divided into a third area and a fourth area; The pinning directions of the magnetic tunnel junctions on the slope structures of the first region and the third region are that the magnetic tunnel junctions located on the first slope are upward along the first slope, and the magnetic tunnel junctions located on the second slope are downward along the second slope; the pinning directions of the magnetic tunnel junctions on the slope structures of the second region and the fourth region are that the magnetic tunnel junctions located on the first slope are downward along the first slope, and the magnetic tunnel junctions located on the second slope are upward along the second slope.

4. The three-axis magnetic sensor according to claim 3, wherein: The magnetic tunnel junctions on the first slope of the slope structure of the first region are connected in series to form a magnetoresistive unit R11; the magnetic tunnel junctions on the second slope of the slope structure of the first region are connected in series to form a magnetoresistive unit R12; the magnetic tunnel junctions on the first slope of the slope structure of the second region are connected in series to form a magnetoresistive unit R14; and the magnetic tunnel junctions on the second slope of the slope structure of the second region are connected in series to form a magnetoresistive unit R13. The magnetic tunnel junctions on the first slope of the slope structure in the third region are connected in series to form a magnetoresistance unit R21; the magnetic tunnel junctions on the second slope of the slope structure in the third region are connected in series to form a magnetoresistance unit R22; the magnetic tunnel junctions on the first slope of the slope structure in the fourth region are connected in series to form a magnetoresistance unit R24; and the magnetic tunnel junctions on the second slope of the slope structure in the fourth region are connected in series to form a magnetoresistance unit R23.

5. The three-axis magnetic sensor according to claim 4, wherein: The magnetoresistance unit R11 , the magnetoresistance unit R14 , the magnetoresistance unit R22 , and the magnetoresistance unit R23 form a first bridge, and the magnetoresistance unit R12 , the magnetoresistance unit R13 , the magnetoresistance unit R21 , and the magnetoresistance unit R24 form a second bridge.

6. The three-axis magnetic sensor according to claim 4, wherein: The magnetoresistance units R11 , R14 , R21 , and R24 form a third bridge, and the magnetoresistance units R12 , R13 , R22 , and R23 form a fourth bridge.

7. The three-axis magnetic sensor according to claim 1, wherein: The pinning directions of the magnetic tunnel junctions located on the first and second slopes of the slope structure are both upward along the slopes, or the pinning directions of the magnetic tunnel junctions located on the first and second slopes of the slope structure are both downward along the slopes.

8. The three-axis magnetic sensor according to claim 7, wherein: The pinning directions of the magnetic tunnel junctions on the slope structures of the first slope array are all upward along the slope; the pinning directions of the magnetic tunnel junctions on the slope structures of the second slope array are all downward along the slope.

9. The three-axis magnetic sensor according to claim 8, wherein: The magnetic tunnel junctions on the first slope surface of the slope structure of the first slope array are connected in series to form a magnetoresistive unit R15; the magnetic tunnel junctions on the second slope surface of the slope structure of the first slope array are connected in series to form a magnetoresistive unit R16; the magnetic tunnel junctions on the first slope surface of the slope structure of the second slope array are connected in series to form a magnetoresistive unit R25; and the magnetic tunnel junctions on the second slope surface of the slope structure of the second slope array are connected in series to form a magnetoresistive unit R26.

10. The three-axis magnetic sensor according to claim 9, wherein: The magnetoresistive unit R15 , the magnetoresistive unit R16 , the magnetoresistive unit R25 , and the magnetoresistive unit R26 are connected to form three types of bridges, respectively, for detecting magnetic fields in corresponding axial directions.

11. The three-axis magnetic sensor according to claim 10, wherein: Two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 constitute a Z-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply end and is connected to terminal A5 through one magnetoresistance unit R16, another magnetoresistance unit R15 is connected to the ground end and is connected to terminal B5 through another magnetoresistance unit R16; one magnetoresistance unit R25 is connected to terminal A5 and is connected to the ground end through one magnetoresistance unit R26, another magnetoresistance unit R25 is connected to terminal B5 and is connected to the power supply end through another magnetoresistance unit R26.

12. The three-axis magnetic sensor according to claim 10, wherein: Two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 constitute an X-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply end and is connected to terminal A6 through a magnetoresistance unit R26, another magnetoresistance unit R15 is connected to terminal B6 and is connected to the ground end through another magnetoresistance unit R26; one magnetoresistance unit R25 is connected to the ground end and is connected to terminal A6 through a magnetoresistance unit R16, another magnetoresistance unit R25 is connected to terminal B6 and is connected to the power supply end through another magnetoresistance unit R16.

13. The three-axis magnetic sensor according to claim 10, wherein: Two magnetoresistance units R15, two magnetoresistance units R16, two magnetoresistance units R25 and two magnetoresistance units R26 constitute a Y-axis induction bridge, wherein one magnetoresistance unit R15 is connected to the power supply end and is connected to terminal A7 through one magnetoresistance unit R25, another magnetoresistance unit R15 is connected to terminal B7 and is connected to the ground end through another magnetoresistance unit R25; one magnetoresistance unit R26 is connected to the ground end and is connected to terminal A7 through one magnetoresistance unit R16, another magnetoresistance unit R26 is connected to terminal B7 and is connected to the power supply end through another magnetoresistance unit R16.

14. The three-axis magnetic sensor according to any one of claims 1 to 13, characterized in that: The slope structure is a boss or groove structure.

15. The three-axis magnetic sensor according to any one of claims 1 to 13, characterized in that: The first slope and the second slope both extend along the central axis of the slope structure; the arrangement directions of the slope structures in the first slope array and the second slope array are both perpendicular to the central axis of the slope structure in the plane of the substrate.

16. The three-axis magnetic sensor according to any one of claims 1 to 13, characterized in that: The number of slope structures, geometric dimensions of the slope structures, the number of magnetic tunnel junctions, and geometric dimensions of the magnetic tunnel junctions in the first slope array and the second slope array are all the same.

17. The three-axis magnetic sensor according to any one of claims 1 to 13, characterized in that: The three-axis magnetic sensor is in the form of a dual chip, the first slope array is arranged on the first chip, the second slope array is arranged on the second chip, the first chip and the second chip are both arranged on the substrate and electrically connected through the substrate.

18. The three-axis magnetic sensor according to any one of claims 1 to 13, characterized in that: The three-axis magnetic sensor is in the form of a single chip, and the first slope array and the second slope array are arranged on the same chip.

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