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), each slope structure (130) comprising a first bevel and a second bevel which are arranged axisymmetrically; each slope structure (130) of the first slope array (110) extends in a plane of the substrate in the direction of a second axis, and each slope structure (130) of the second slope array (120) extends in the plane of the substrate in the direction of a first axis; 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 the first bevel is along the direction of the first bevel, and the pinning direction of the magnetic tunnel junctions (140) located on the 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 202410170477.8 and invention name “Three-axis magnetic sensor”, the entire contents of which are incorporated by reference into this application. 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 that are axially symmetrically arranged; each slope structure of the first slope array extends along the second axis within the plane of the substrate, and each slope structure of the second slope array extends along the first axis within the plane of the substrate; a plurality of magnetic tunnel junctions are provided on each slope structure of the first slope array and the second slope array, and the magnetic The pinning direction of the magnetic tunnel junction is along the first slope direction, and the pinning direction of the magnetic tunnel junction located on the second slope is along the second slope direction; the magnetic tunnel junctions 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, so that the magnetic tunnel junctions located in 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.

[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 cross-sectional view of the slope structure in FIG1 along lines A1-A1', A2-A2', B1-B1', and B2-B2';

[0010] FIG3 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;

[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 another embodiment;

[0012] FIG5 is a schematic diagram of annealing directions of different regions in another embodiment;

[0013] FIG6 is a schematic structural diagram of a three-axis magnetic sensor in another embodiment;

[0014] FIG7 is a schematic cross-sectional view of the slope structure along lines AA' and BB' in FIG6 ;

[0015] FIG8 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

[0016] 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.

[0017] In one embodiment, as shown in FIG1 and FIG2 , 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 axially symmetrically. Each slope structure 130 of the first slope array 110 extends along the second axis within the plane of the substrate, while each slope structure 130 of the second slope array 120 extends along the first axis within the plane of the substrate. The plurality of magnetic tunnel junctions 140 are provided on each of the slope structures 130 of 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. Thus, 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 the first, second, and third axes. The first, second, and third axes are perpendicular to each other, and the third axis is also perpendicular to the plane of the substrate.

[0018] Specifically, the arrangement 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 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. Each slope structure 130 of the first slope array 110 extends along the second axis direction in the plane of the substrate, which means that the angle between the orthographic projection of each slope structure 130 of the first slope array 110 in the plane of the substrate and the positive direction of the first axis is 90 degrees. Each slope structure 130 of the second slope array 120 extends along the first axis direction in the plane of the substrate, which means that the angle between the orthographic projection of each slope structure 130 of the second slope array 120 in the plane of the substrate and the positive direction of the first axis is 0 degrees.

[0019] 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.

[0020] By setting the pinning directions of the multiple magnetic tunnel junctions 140 to be 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, which can induce a magnetic field in the Z-axis direction. Moreover, because the slope structure 130 with the same slope gradient is adopted, 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, each of the multiple slope structures 130 of the first slope array 110 is configured to extend along the Y-axis direction within the plane of the substrate, so that the pinning directions of the magnetic tunnel junctions 140 located in the first slope array 110 have only equal and identical or opposite components along the X-axis direction within the plane of the substrate (i.e., within the XY plane), which can sense a magnetic field in the X-axis direction. Each of the multiple slope structures 130 of the second slope array 120 is configured to extend along the X-axis direction within the plane of the substrate, so that the pinning directions of the magnetic tunnel junctions 140 located in the second slope array 120 have only equal and identical or opposite components along the Y-axis direction within the plane of the substrate, which can sense a magnetic field in the Y-axis direction. In this way, the magnetic tunnel junctions 140 having 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. As a result, 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. Furthermore, the magnetoresistive units located in the first slope array 110 change their resistance based on changes in the components of the external magnetic field in the X-axis and Z-axis directions, and the magnetoresistive units located in the second slope array 110 change their resistance based on changes in the components of the external magnetic field in the Y-axis and Z-axis directions. The components of the resistance changes of the magnetoresistive units in the first slope array 110 are equal in magnitude and have the same or opposite directions along the X-axis. The components of the resistance changes of the magnetoresistive units in the second slope array 120 are equal in magnitude and have the same or opposite directions along the Y-axis. The components of the resistance changes of the magnetoresistive units in the first slope array 110 and the second slope array 120 are equal in magnitude and have the same or opposite directions along the Z-axis. 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.

[0021] In one embodiment, as shown in FIG1 , both the first and second inclined surfaces extend along the central axis H of the slope structures 130, allowing for the arrangement of as many magnetic tunnel junctions 140 as possible. Specifically, each of the plurality of slope structures 130 in the first slope array 110 is configured to extend along the Y-axis within the plane of the substrate, meaning that the central axis H of the slope structures 130 in the first slope array 110 extends along the Y-axis; and each of the plurality of slope structures 130 in the second slope array 120 is configured to extend along the X-axis within the plane of the substrate, meaning that the central axis H of the slope structures 130 in the second slope array 120 extends along the X-axis. The arrangement direction of the slope structures 130 in both the first and second slope arrays 110, 120 is perpendicular to the central axis H of the slope structures 130 within the plane of the substrate. The arrangement direction of the slope structures 130 in the first slope array 110 is perpendicular to the arrangement direction of the slope structures 130 in the second slope array 120. Specifically, the slope structures 130 in the first slope array 110 are arranged in an array along the X-axis direction, and the slope structures 130 in the second slope array 120 are arranged in an array along the Y-axis direction.

[0022] 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.

[0023] 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.

[0024] The pinning direction of the magnetic tunnel junction 140 can be determined by the annealing magnetic field. As shown in FIG1 , 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.

[0025] 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 1 and 2, 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 still 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.

[0026] 1 and 2 , also taking the design of the slope structure 130 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 such that the magnetic tunnel junctions 140 located on the first slope W1 are upward along the first slope, and the magnetic tunnel junctions 140 located on the second slope W2 are downward along the second slope; 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 such that the magnetic tunnel junctions 140 located on the first slope W1 are downward along the first slope, and the magnetic tunnel junctions 140 located on the second slope are upward along the second slope W2. In this way, 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 both 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 second region 12 both have a component along the positive 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 third region 13 both have a component along the positive direction of the Y axis, and 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 fourth region 14 both have a component along the positive direction of the Y axis. 40 has a component along the negative direction of the Y axis, the pinning directions of the magnetic tunnel junction 140 of the first slope W1 of the slope structure 130 located in the first region 11 and the third region 13 and the magnetic tunnel junction 140 of the second slope W2 of the slope structure 130 located in the second region 12 and the fourth region 14 have a component along the positive direction of the Z axis, and the pinning directions of the magnetic tunnel junction 140 of the second slope W2 of the slope structure 130 located in the first region 11 and the third region 13 and the magnetic tunnel junction 140 of the first slope W1 of the slope structure 130 located in the second region 12 and the fourth region 14 have a component along the negative direction of the Z axis.

[0027] 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.

[0028] As shown in Figures 1 and 2, taking the slope structure 130 using a boss as an example, the pinning directions of the magnetic tunnel junctions 140 in the magnetoresistive units R11, R12, R13, and R14 have components only in the X-axis and Z-axis, and the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistive unit R11 are -X and +Z, the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistive unit R12 are -X and -Z, the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistive unit R13 are +X and +Z, and the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistive unit R14 are +X and -Z. The pinning directions of the magnetic tunnel junctions 140 in the magnetoresistance units R21, R22, R23, and R24 have components only in the Y-axis and the Z-axis, and the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistance unit R21 are +Y and +Z, the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistance unit R22 are +Y and -Z, the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistance unit R23 are -Y and +Z, and the component directions of the pinning direction of the magnetic tunnel junction 140 in the magnetoresistance unit R24 are -Y and -Z.

[0029] 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.

[0030] 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.

[0031] Specifically, as shown in Figure 3, 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 the first 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 the second signal.

[0032] 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.

[0033] 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 third 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 fourth signal.

[0034] As shown in Figure 3, 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 terminal G1 and terminal C1 output the first signal, an adjacent magnetoresistive unit R11 and a magnetoresistive unit R23 constitute a bridge arm, and another adjacent magnetoresistive unit R11 and another magnetoresistive unit R23 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the negative direction of the X axis, along the negative direction of the Y axis, and along the positive direction of the Z axis; an adjacent magnetoresistive unit R14 and a magnetoresistive unit R22 constitute a bridge arm, and another adjacent magnetoresistive unit R14 and another magnetoresistive unit R22 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the positive direction of the X axis, along the positive direction of the Y axis, and along the negative direction of the Z axis. In this way, in this output mode, the first signal corresponds to the -X axis magnetic field, the -Y 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 signal, an adjacent magnetoresistive unit R11 and a magnetoresistive unit R22 form a bridge arm, and another adjacent magnetoresistive unit R11 and another magnetoresistive unit R22 form another bridge arm. In each bridge arm, the component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the negative direction of the X-axis, and the components in the Y-axis direction are all along the positive direction of the Y-axis. An adjacent magnetoresistive unit R14 and a magnetoresistive unit R23 form a bridge arm, and another adjacent magnetoresistive unit R14 and another magnetoresistive unit R23 form another bridge arm. In each bridge arm, the component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the positive direction of the X-axis, and the component in the Y-axis direction is all along the negative direction of the Y-axis. In this way, in this output mode, the second signal corresponds to the -X-axis magnetic field and the +Y-axis magnetic field.

[0035] 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 terminal G2 and terminal C2 output the third signal, an adjacent magnetoresistance unit R12 and a magnetoresistance unit R24 constitute a bridge arm, and another adjacent magnetoresistance unit R12 and another magnetoresistance unit R24 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the negative direction of the X axis, along the negative direction of the Y axis, and along the negative direction of the Z axis; an adjacent magnetoresistance unit R13 and a magnetoresistance unit R21 constitute a bridge arm, and another adjacent magnetoresistance unit R13 and another magnetoresistance unit R21 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the positive direction of the X axis, along the positive direction of the Y axis, and along the positive direction of the Z axis. In this way, in this output mode, the third signal corresponds to the -X axis magnetic field, the -Y 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 fourth 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 component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the negative direction of the X-axis, and the component in the Y-axis direction is 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 component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the positive direction of the X-axis, 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 fourth signal corresponds to the -X-axis magnetic field and the +Y-axis magnetic field.

[0036] Thus, subtracting the first and third signals can correspond to the Z-axis magnetic field. Furthermore, adding the first and third signals and then adding or subtracting them from the second and fourth signals can correspond to the X-axis magnetic field and the Y-axis magnetic field, respectively. This means that the first and second bridges can detect three-axis magnetic fields.

[0037] 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.

[0038] Specifically, as shown in Figure 4, 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 the first 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 the second signal.

[0039] 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 third 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 fourth signal.

[0040] Taking the ramp structure 130 using 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 signal, an adjacent magnetoresistive unit R11 and a magnetoresistive unit R21 constitute a bridge arm, and another adjacent magnetoresistive unit R11 and another magnetoresistive unit R21 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the negative direction of the X axis, along the positive direction of the Y axis, and along the positive direction of the Z axis; an adjacent magnetoresistive unit R14 and a magnetoresistive unit R24 constitute a bridge arm, and another adjacent magnetoresistive unit R14 and another magnetoresistive unit R24 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the positive direction of the X axis, along the negative direction of the Y axis, and along the negative direction of the Z axis. In this way, in this output mode, the first signal corresponds to the -X axis magnetic field, 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 terminal D3 and terminal H3 output the second signal, an adjacent magnetoresistive unit R11 and a magnetoresistive unit R24 form a bridge arm, and another adjacent magnetoresistive unit R11 and another magnetoresistive unit R24 form another bridge arm. In each bridge arm, the component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the negative direction of the X-axis, and the component in the Y-axis direction is along the negative direction of the Y-axis. An adjacent magnetoresistive unit R14 and a magnetoresistive unit R21 form a bridge arm, and another adjacent magnetoresistive unit R14 and another magnetoresistive unit R21 form another bridge arm. In each bridge arm, the component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the positive direction of the X-axis, and the components in the Y-axis direction are all along the positive direction of the Y-axis. In this way, in this output mode, the second signal corresponds to the -X-axis magnetic field and the -Y-axis magnetic field.

[0041] 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 terminal G4 and terminal C4 output the third signal, an adjacent magnetoresistance unit R12 and a magnetoresistance unit R22 constitute a bridge arm, and another adjacent magnetoresistance unit R12 and another magnetoresistance unit R22 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the negative direction of the X axis, along the positive direction of the Y axis, and along the negative direction of the Z axis; an adjacent magnetoresistance unit R13 and a magnetoresistance unit R23 constitute a bridge arm, and another adjacent magnetoresistance unit R13 and another magnetoresistance unit R23 constitute another bridge arm, and the pinning direction of each bridge arm in the component direction of the three axes is along the positive direction of the X axis, along the negative direction of the Y axis, and along the positive direction of the Z axis. In this way, in this output mode, the third signal corresponds to the -X axis magnetic field, 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 fourth 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 component of the pinning direction in the Z-axis direction is offset, the component in the X-axis direction is along the negative direction of the X-axis, and the component in the Y-axis direction is along the negative direction of the Y-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 this way, in this output mode, the fourth signal corresponds to the -X-axis magnetic field and the -Y-axis magnetic field.

[0042] Thus, subtracting the first and third signals can correspond to the Z-axis magnetic field. Furthermore, adding the first and third signals and then adding or subtracting them from the second and fourth signals can correspond to the X-axis magnetic field and the Y-axis magnetic field, respectively. This means that the third and fourth bridges can detect three-axis magnetic fields.

[0043] 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.

[0044] The pinning direction of the magnetic tunnel junction 140 can be determined by the annealing magnetic field. As shown in Figure 5, 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 direction of the magnetic tunnel junctions 140 located on the first and second slopes is either upward or downward along the slope.

[0045] 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.

[0046] Referring to Figures 6 and 7 , 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 a component along the positive X-axis direction and a component along the positive Z-axis direction, while the pinning directions of the magnetic tunnel junctions 140 on the second slope of the slope structure 130 have a component along the negative X-axis direction and a component along the positive Z-axis direction. 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 Y axis and a component along the negative direction of the Z axis, and 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 Y axis and a component along the negative direction of the Z axis.

[0047] The magnetic tunnel junctions 140 on the first slope surface of the slope structure 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 slope surface of the slope structure 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 slope surface of the slope structure 130 of the second slope array 120 are connected in series to form a magnetoresistive unit R25; and the magnetic tunnel junctions 140 on the second slope surface of the slope structure 130 of the second slope array 120 are connected in series to form a magnetoresistive unit R26.

[0048] As shown in Figures 6 and 7, 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 and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R16 on the three axes are -X and +Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R25 on the three axes are -Y and -Z, respectively. The pinning direction components of the magnetic tunnel junction 140 in the magnetoresistive unit R26 on the three axes are +Y and -Z, respectively.

[0049] 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.

[0050] As shown in Figure 8, 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. An adjacent magnetoresistance unit R15 and a magnetoresistance unit R16 constitute a bridge arm, and another adjacent magnetoresistance unit R15 and another magnetoresistance unit R16 constitute another bridge arm. In each bridge arm, the component of the pinning direction in the X-axis direction is offset, and the components in the Z-axis direction are all along the positive direction of the Z-axis; an adjacent magnetoresistance unit R25 and a magnetoresistance unit R26 constitute a bridge arm, and another adjacent magnetoresistance unit R25 and another magnetoresistance unit R26 constitute another bridge arm. In each bridge arm, the component of the pinning direction in the Y-axis direction is offset, and the components in the Z-axis direction are all along the negative direction of the Z-axis. In this way, the output signals of terminal A5 and terminal B5 only contain the induction component of the Z-axis magnetic field.

[0051] Furthermore, two magnetoresistive units R15 and two magnetoresistive units R16 are selected to form an X-axis inductive bridge. One magnetoresistive unit R15 is connected to the power supply terminal Vcc and terminal A6, the other magnetoresistive unit R15 is connected to terminal B6 and ground terminal GND, one magnetoresistive unit R16 is connected to terminal A6 and ground terminal GND, and the other magnetoresistive unit R16 is connected to the power supply terminal Vcc and terminal B6. When terminals A6 and B6 of the X-axis inductive bridge output signals, magnetoresistive units R15 and R16 each serve as a separate bridge arm. Their pinning directions both have a component along the positive Z-axis and no component along the Y-axis, and the X-axis components are in opposite directions. The resistance of magnetoresistive unit R15 increases with an increase in the negative X-axis magnetic field, while the resistance of magnetoresistive unit R16 decreases with an increase in the negative X-axis magnetic field. Consequently, the output signals from terminals A6 and B6 contain only the inductive component of the X-axis magnetic field.

[0052] Furthermore, two magnetoresistive units R25 and two magnetoresistive units R26 are selected to form a Y-axis inductive bridge. One magnetoresistive unit R25 is connected to the power supply terminal Vcc and terminal B7, and the other magnetoresistive unit R25 is connected to terminal A7 and ground terminal GND. One magnetoresistive unit R26 is connected to terminal B7 and ground terminal GND, and the other magnetoresistive unit R26 is connected to the power supply terminal Vcc and terminal A7. When terminals A7 and B7 of the Y-axis inductive bridge output signals, magnetoresistive units R25 and R26 each serve as a separate bridge arm. Their pinning directions both have a component along the negative Z-axis, no component along the X-axis, and the Y-axis components are in opposite directions. The resistance of magnetoresistive unit R26 increases with an increase in the negative Y-axis magnetic field, while the resistance of magnetoresistive unit R25 decreases with an increase in the negative Y-axis magnetic field. Thus, the output signals from terminals A7 and B7 contain only the inductive component of the Y-axis magnetic field.

[0053] 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.

[0054] Based on the specific connection methods of the X-axis induction single bridge, the Y-axis induction single bridge and the Z-axis induction single bridge, three independent bridges can be set up; a switching circuit can also be set up to switch between three modes. In different modes, each magnetic resistance unit is connected to form a different bridge.

[0055] 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.

[0056] 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.

[0057] It can be understood that in other embodiments, the substrate may also be a silicon substrate.

[0058] 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.

[0059] 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 along an axis; each slope structure of the first slope array extends along a second axis in the plane of the substrate, and each slope structure of the second slope array extends along a first axis in the plane of the substrate; the plurality of magnetic tunnel junctions are arranged on each slope structure of the first slope array and the second slope array, and the magnetic tunnel junctions located on the first slope surface The pinning direction of the magnetic tunnel junctions is along the first slope direction, and the pinning direction of the magnetic tunnel junctions located on the second slope is along the second slope direction; the magnetic tunnel junctions 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, so that the magnetic tunnel junctions located in 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 both upward along the first slope when located on the first slope, and downward along the second slope when located on the second slope; the pinning directions of the magnetic tunnel junctions on the slope structures of the second region and the fourth region are both downward along the first slope when located on the first slope, and upward along the second slope when located on 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 and two magnetoresistance units R16 constitute an X-axis inductive bridge, wherein one magnetoresistance unit R15 is connected to the power supply end and terminal A6, another magnetoresistance unit R15 is connected to terminal B6 and the ground end, one magnetoresistance unit R16 is connected to terminal A6 and the ground end, and another magnetoresistance unit R16 is connected to the power supply end and terminal B6.

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

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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