A three-axis magnetic sensor

Abstract

The utility model provides a kind of three-axis magnetic sensor, it includes: first anisotropic magnetoresistance sensing unit, it is used to sense the external magnetic field of X-axis direction to generate X-axis sensing voltage;Second anisotropic magnetoresistance sensing unit, it is used to sense the external magnetic field of Y-axis direction to generate Y-axis sensing voltage;Abnormal hall unit, it is used to sense the external magnetic field of Z-axis direction to generate Z-axis sensing voltage;Signal processing circuit, with first anisotropic magnetoresistance sensing unit, second anisotropic magnetoresistance sensing unit and abnormal hall unit electric connection.Compared with prior art, the utility model combines magnetoresistance technology manufacturing and abnormal hall effect, adopts complete plane technology to manufacture three-axis magnetic sensor, realize the detection of three-axis magnetic field on the same chip, and three-axis sensitive unit is on the same layer, reduces the difficulty of process manufacturing.

Description

[Technical Field]

[0001] This utility model relates to the field of magnetic sensor technology, and in particular to a triaxial magnetic sensor. [Background Technology]

[0002] The sensing direction of a magnetoresistive sensor unit is generally parallel to the thin film surface, typically sensitive along the X or Y axis. To achieve Z-axis detection, a flux concentrator needs to be introduced, or the sensing unit needs to be fabricated on a ramp to detect the Z-axis component. Introducing a flux concentrator increases hysteresis, reducing sensor performance. Fabricating the sensing unit on a ramp increases the difficulty of fabrication and production. Both methods increase the number of processing steps, thus raising costs.

[0003] Therefore, it is necessary to propose a new technical solution to overcome the above problems. [Utility Model Content]

[0004] The purpose of this invention is to provide a triaxial magnetic sensor that combines magnetoresistive technology with the anomalous Hall effect. The triaxial magnetic sensor is manufactured using a completely planar process, enabling the detection of triaxial magnetic fields on the same chip. Furthermore, the triaxial sensing units are on the same layer, which reduces the difficulty of the manufacturing process.

[0005] To achieve the purpose of the invention, according to one aspect of the present invention, the present invention provides a triaxial magnetic sensor, which includes: a first anisotropic magnetoresistive sensing unit, which is used to sense an external magnetic field in the X-axis direction to generate an X-axis sensing voltage, wherein the X-axis sensing voltage represents the magnetic field component in the X-axis direction of the sensed external magnetic field.

[0006] A second anisotropic magnetoresistive sensing unit is used to sense an external magnetic field in the Y-axis direction to generate a Y-axis sensing voltage, wherein the Y-axis sensing voltage represents the magnetic field component of the sensed external magnetic field in the Y-axis direction, and the X-axis and Y-axis are orthogonal to each other; an anomalous Hall unit is used to sense an external magnetic field in the Z-axis direction to generate a Z-axis sensing voltage, wherein the Z-axis sensing voltage represents the magnetic field component of the sensed external magnetic field in the Z-axis direction, and the Z-axis is orthogonal to the X-axis and Y-axis; a signal processing circuit is electrically connected to the first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, and the anomalous Hall unit, wherein the signal processing circuit is used to convert the X-axis sensing voltage into the magnetic field component of the external magnetic field in the X-axis direction, convert the Y-axis sensing voltage into the magnetic field component of the external magnetic field in the Y-axis direction, and convert the Z-axis sensing voltage into the magnetic field component of the external magnetic field in the Z-axis direction.

[0007] Compared with existing technologies, this invention combines magnetoresistive technology with the anomalous Hall effect, and uses a completely planar process to manufacture a triaxial magnetic sensor, realizing the detection of triaxial magnetic fields on the same chip, and the triaxial sensing units are on the same layer, which reduces the difficulty of manufacturing process. [Attached Image Description]

[0008] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Among them:

[0009] Figure 1 This is a longitudinal cross-sectional schematic diagram of a single-chip triaxial magnetic sensor in one embodiment of the present invention;

[0010] Figure 2 In one embodiment of this utility model, as shown Figure 1 The diagram shows the equivalent bridge of a two-axis AMR sensor (or AMR bridge).

[0011] Figure 3 In one embodiment of this utility model, as Figure 1 The diagram shows the first structural design of the anomalous Hall unit.

[0012] Figure 4 In one embodiment of this utility model, as shown Figure 1 The diagram shows a second structural representation of the anomalous Hall unit.

[0013] Figure 5 In one embodiment of this utility model, as shown Figure 1 The diagram shows the third structure of the anomalous Hall unit.

[0014] Figure 6 In one embodiment of this utility model, as Figure 1 The diagram shows the fourth structure of the anomalous Hall unit.

[0015] Figure 7 In one embodiment of this utility model, as shown Figure 1 The diagram shows the structure of a single-chip triaxial magnetic sensor.

Detailed Implementation Methods

[0016] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. Unless otherwise specified, the terms coupling, connection, linking, and interconnection used herein to indicate electrical connection mean direct or indirect connection. For example, A being connected to B includes both a direct electrical connection between A and B and a connection between A and B via electrical components or circuits.

[0018] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "back", "positive", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] Please refer to Figure 1 As shown, it is a longitudinal cross-sectional schematic diagram of a single-chip triaxial magnetic sensor in one embodiment of the present invention. Figure 1 The single-chip triaxial magnetic sensor shown includes a first anisotropic magnetoresistive (AMR) sensing unit, a second anisotropic magnetoresistive (AMR) sensing unit, an anomalous Hall element, and a signal processing circuit, all formed on the same silicon substrate (or semiconductor substrate) 110. For ease of description, in... Figure 1 The Cartesian coordinate system is defined, in which the X-axis extends from left to right, the Z-axis extends from bottom to top, and the Y-axis extends away from the observer and into the page. The Z-axis, X-axis, and Y-axis satisfy the right-hand rule, and the plane defined by the X-axis and Y-axis is parallel to the single-chip plane.

[0020] The first anisotropic magnetoresistive (AMR) sensing unit is used to sense the external magnetic field in the X-axis direction to generate an X-axis sensing voltage (or X-axis linear voltage signal), which represents the magnetic field component (or magnetic induction intensity and direction in the X-axis direction) of the sensed external magnetic field.

[0021] The second anisotropic magnetoresistive (AMR) sensing unit is used to sense the external magnetic field in the Y-axis direction to generate a Y-axis sensing voltage (or a Y-axis linear voltage signal). The Y-axis sensing voltage represents the magnetic field component (or magnetic induction intensity and direction in the Y-axis direction) of the sensed external magnetic field in the Y-axis direction, wherein the X-axis and Y-axis are orthogonal to each other.

[0022] An anomalous Hall element is used to sense an external magnetic field along the Z-axis to generate a Z-axis sensing voltage (or a Z-axis linear voltage signal). The Z-axis sensing voltage represents the magnetic field component (or the magnetic flux density and direction) along the Z-axis of the sensed external magnetic field. The Z-axis is orthogonal to the X and Y axes. The first and second anisotropic magnetoresistive (AMR) sensing units constitute a biaxial AMR sensor (or an AMR bridge).

[0023] The signal processing circuit is electrically connected to the first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, and the anomalous Hall unit. The signal processing circuit is used to convert the X-axis sensed voltage into the magnetic field component of the external magnetic field in the X-axis direction, the Y-axis sensed voltage into the magnetic field component of the external magnetic field in the Y-axis direction, and the Z-axis sensed voltage into the magnetic field component of the external magnetic field in the Z-axis direction.

[0024] The signal processing circuit is disposed on the first structural layer 120, and the first anisotropic magnetoresistive (AMR) sensing unit, the second anisotropic magnetoresistive (AMR) sensing unit, and the anomalous Hall unit are disposed on the second structural layer 140. The first structural layer 120 and the second structural layer 140 are stacked on the silicon substrate 110. The first structural layer 120, where the signal processing circuit is disposed, is located on the substrate 110; the second structural layer 140, where the first anisotropic magnetoresistive (AMR) sensing unit, the second anisotropic magnetoresistive (AMR) sensing unit, and the anomalous Hall unit are disposed, is located above the first structural layer 110. The signal processing circuit and the first anisotropic magnetoresistive (AMR) sensing unit, the second anisotropic magnetoresistive (AMR) sensing unit, and the anomalous Hall unit are electrically connected through via metal (not shown). Structural layers 120 and 140 consist of multiple semiconductor process layers to achieve a specific function, forming a complete functional structural layer, not a single layer. In one embodiment, substrate 110 is a commonly used P-type semiconductor substrate; the signal processing circuit in the first structural layer 120 is fabricated using standard CMOS technology, and this part includes a multilayer structure.

[0025] exist Figure 1In the illustrated embodiment, the single-chip triaxial magnetic sensor further includes an isolation layer 130 and a third structural layer 150. The isolation layer 130 is located between the first structural layer 120 and the second structural layer 140; the third structural layer 150 is located above the second structural layer 140. The isolation layer 130 has a through-hole (not shown) extending through its thickness. A through-hole metal (not shown) passes through the through-hole (or through the isolation layer) to electrically connect the first anisotropic magnetoresistive (AMR) sensing unit, the second anisotropic magnetoresistive (AMR) sensing unit, the anomalous Hall unit, and the signal processing circuit. The isolation layer 130 may be composed of materials such as silicon nitride or silicon dioxide, and the through-hole metal may be made of materials such as Al or Cu. The roughness of the upper surface of the isolation layer 130 is sufficiently small and can be reduced by planarization methods such as chemical mechanical polishing. The third structural layer 150 includes a protective layer and electrodes thereon. The electrodes are connected to the signal processing circuit through the through-hole metal, and the output signal of the signal processing circuit is transmitted to the electrodes of the third structural layer 150 through the through-hole metal.

[0026] Figure 1 The single-chip triaxial magnetic sensor shown is fully integrated from a single chip, and the final package uses wafer-level packaging, or plastic encapsulation.

[0027] Please refer to Figure 2 As shown, this is one embodiment of the present invention. Figure 1 The diagram shows the equivalent bridge of a two-axis AMR sensor (or AMR bridge). Figure 2 In this context, a rectangular coordinate system is defined, where the x-axis extends from left to right and the y-axis extends from bottom to top. Figure 2 The first anisotropic magnetoresistive (AMR) sensing unit shown includes a first Wheatstone bridge 200a, and the second anisotropic magnetoresistive (AMR) sensing unit includes a second Wheatstone bridge 200b. The first Wheatstone bridge 200a is used to sense an external magnetic field in the X-axis direction to generate an X-axis sensing voltage; the second Wheatstone bridge 200b is used to sense an external magnetic field in the Y-axis direction to generate a Y-axis sensing voltage.

[0028] The first Wheatstone bridge 200a includes bridge arms 210a, 210b, 210c, and 210d, which are interconnected to form a Wheatstone bridge. Bridge arm 210a is connected between the power supply terminal VDD2 and the first signal terminal V3 (e.g., the positive signal terminal V+); bridge arm 210b is connected between the first signal terminal V3 and the ground terminal GND2; bridge arm 210c is connected between the second signal terminal V4 (e.g., the negative signal terminal V-) and the ground terminal GND2; and bridge arm 210d is connected between the power supply terminal VDD2 and the second signal terminal V4. The output terminals of the first Wheatstone bridge 200a are the first signal terminal V3 and the second signal terminal V4, that is, the difference between the first signal terminal V3 and the second signal terminal V4 of the first Wheatstone bridge 200a is the X-axis sensing voltage.

[0029] In the first Wheatstone bridge 200a, each bridge arm 210a, 210b, 210c, and 210d includes a magnetoresistive strip 230 and several parallel conductive strips 220. The long side of the magnetoresistive strip 230 is parallel to the magnetic easy axis of the bridge arm. The several parallel conductive strips 220 are formed on the magnetoresistive strip 230 and at a predetermined angle to it. The conductive strips 220 are made of a highly conductive metal, and a portion of the structure of the conductive strips 220 acts as a short-circuit bar above the magnetoresistive strip 230 to guide the direction of current flow.

[0030] Among them, the magnetoresistive strip 230 is a magnetic material layer, such as NiFe, CoFeB, etc. The conductive strip 220 is formed into a strip structure on the magnetic material layer by photolithography, and the material is a metal with high electrical conductivity, such as Al, Cu or AlCu alloy.

[0031] The structure of the second Wheatstone bridge 200b is the same as that of the first Wheatstone bridge 200a. Compared with the first Wheatstone bridge 200a, the second Wheatstone bridge 200b is rotated by 90 degrees. Figure 2 In the illustrated embodiment, the rotation is 90 degrees counterclockwise, but it can also be rotated 90 degrees clockwise. Alternatively, the first Wheatstone bridge 200a and the second Wheatstone bridge 200b can be described as orthogonal.

[0032] In a specific embodiment of this utility model, the bridge arms 210a, 210b, 210c, and 210d include a plurality of parallel magnetoresistive strips 230, wherein each magnetoresistive strip 230 has a plurality of parallel conductive strips 220 formed thereon, and the plurality of magnetoresistive strips 230 are connected end to end.

[0033] In summary, the biaxial AMR sensor (or AMR bridge) in this invention can be manufactured using a completely planar process.

[0034] Please refer to Figure 3As shown, this is one embodiment of the present invention. Figure 1 The diagram shows the first structural schematic of the anomalous Hall unit. Figure 3 The anomalous Hall effect unit shown includes a first strip 301 extending along a first direction; a first electrode 303 and a second electrode 305 formed at both ends of the first strip 301 and connected to the first strip 301; a second strip 306 extending along a second direction and intersecting the first strip 301, wherein the first direction is perpendicular to the second direction; and a third electrode 302 and a fourth electrode 304 formed at both ends of the second strip 306 and connected to the second strip 306.

[0035] exist Figure 3 In the specific embodiment shown, both the first strip portion 301 and the second strip portion 306 are made of magnetic material, and the magnetic material layer of the first strip portion 301 and the second strip portion 306 is the same magnetic material layer as the magnetic material layer of the magnetoresistive strip 230 in the Wheatstone bridges 200a and 200b shown above. Alternatively, in the specific embodiment of this invention, the magnetic material layer in the anomalous Hall unit is the same magnetic material layer as the magnetic material layer in the first anisotropic magnetoresistive sensing unit and the second anisotropic magnetoresistive sensing unit.

[0036] exist Figure 3 In the specific embodiment shown, the third electrode 302 can be the power supply terminal VDD3, the fourth electrode 304 can be the ground terminal GND3, the first electrode 303 can be the first signal terminal V5, the second electrode 305 can be the second signal terminal V6, and the difference between the first signal terminal V5 and the second signal terminal V6 is the Z-axis sensing voltage. Figure 3 The four electrodes of the anomalous Hall unit shown can be used in a clockwise or counterclockwise rotation as the power supply terminal VDD3, the first signal terminal V5, the ground terminal GND3, and the second signal terminal V6. For example, the first electrode 303 is the power supply terminal VDD3, the fourth electrode 304 is the first signal terminal V5, the second electrode 305 is the ground terminal GND3, and the third electrode 302 is the second signal terminal V6.

[0037] Please refer to Figure 4 As shown, this is one embodiment of the present invention. Figure 1 The diagram shows a second structural schematic of the anomalous Hall unit. Figure 4 The anomalous Hall effect unit shown includes a first strip 401 extending along a first direction; a first electrode 403 and a second electrode 405 formed at both ends of the first strip 401 and connected to the first strip 401; a second strip 406 extending along a second direction and intersecting the first strip 401, wherein the first direction is perpendicular to the second direction; and a third electrode 402 and a fourth electrode 404 formed at both ends of the second strip 406 and connected to the second strip 406.

[0038] exist Figure 4 In the specific embodiment shown, the first strip 401 is made of magnetic material; the second strip 406 includes a first arm 4062 and a second arm 4064, the first arm 4062 is located on one side of the first strip 401 and connected to the first strip 401; the second arm 4064 is located on the other side of the first strip 401 and connected to the first strip 401; the part where the first strip 401 and the second strip 406 intersect is made of magnetic material; the first arm 4062 and the second arm 4064 are made of a material with a higher conductivity than magnetic materials (e.g., high conductivity materials such as AlCu); the magnetic material layer of the first strip 401 is the same magnetic material as the magnetic material layer of the magnetoresistive strip 230 in the Wheatstone bridges 200a and 200b shown above. Alternatively, in a specific embodiment of this utility model, the magnetic material layer in the anomalous Hall unit is the same magnetic material as the magnetic material layer in the first anisotropic magnetoresistive sensing unit and the second anisotropic magnetoresistive sensing unit.

[0039] Figure 4 The four electrodes of the anomalous Hall effect unit shown cannot be used in a clockwise or counterclockwise rotation as the power supply terminal VDD3, the first signal terminal V5, the ground terminal GND3, and the second signal terminal V6. Figure 4 In the specific embodiment shown, the two electrodes 403 and 405 of the first strip portion 401 are the power supply terminal VDD3 and the ground terminal GND3, respectively, and the two electrodes 402 and 404 of the second strip portion 406 are the first signal terminal V5 and the second signal terminal V6, respectively.

[0040] Please refer to Figure 5 As shown, this is one embodiment of the present invention. Figure 1 The diagram shows the third structure of the anomalous Hall unit. Figure 5 The anomalous Hall effect unit shown includes a first strip 501 extending along a first direction; a first electrode 503 and a second electrode 505 formed at both ends of the first strip 501 and connected to the first strip 501; a second strip 506 extending along a second direction and intersecting the first strip 501, wherein the first direction is perpendicular to the second direction; and a third electrode 502 and a fourth electrode 504 formed at both ends of the second strip 506 and connected to the second strip 506.

[0041] exist Figure 5In the specific embodiment shown, the first strip portion 501 includes a first end portion 5012, a second end portion 5014, and a connecting portion 5016 located between the first end portion 5012 and the second end portion 5014. The end of the connecting portion 5014 connected to the first end portion 5012 or the second end portion 5014 is semi-circular, which facilitates the distribution of magnetization. The second strip portion 506 includes a first arm portion 5062 and a second arm portion 5064. The first arm portion 5062 is located on one side of the first strip portion 501 and connected to the first strip portion 501; the second arm portion 5064 is located on the other side of the first strip portion 501 and connected to the first strip portion 501. The connecting portion 5016 is made of a magnetic material, and the portion where the first strip portion 501 and the second strip portion 506 intersect is made of a magnetic material; the first arm portion 5062 and the second arm portion 5064 are made of a material with a higher electrical conductivity than the magnetic material; the first end portion 5012 and the second end portion 5014 are made of a material with a higher electrical conductivity than the magnetic material. The magnetic material layer of the connecting part 5016 is the same magnetic material as the magnetic material layer of the magnetoresistive strip 230 in the Wheatstone bridges 200a and 200b shown above. Alternatively, in a specific embodiment of this invention, the magnetic material layer in the anomalous Hall unit is the same magnetic material as the magnetic material layers in the first anisotropic magnetoresistive sensing unit and the second anisotropic magnetoresistive sensing unit.

[0042] Figure 5 The four electrodes of the anomalous Hall effect unit shown cannot be used in a clockwise or counterclockwise rotation as the power supply terminal VDD3, the first signal terminal V5, the ground terminal GND3, and the second signal terminal V6. Figure 5 In the specific embodiment shown, the two electrodes 503 and 505 of the first strip portion 501 are the power supply terminal VDD3 and the ground terminal GND3, respectively, and the two electrodes 502 and 504 of the second strip portion 506 are the first signal terminal V5 and the second signal terminal V6, respectively.

[0043] Please refer to Figure 6 As shown, this is one embodiment of the present invention. Figure 1 The diagram shows the fourth structure of the anomalous Hall unit. Figure 6 The anomalous Hall effect unit shown includes a first strip 601 extending along a first direction; a first electrode 603 and a second electrode 605 formed at both ends of the first strip 601 and connected to the first strip 601; a second strip 606 extending along a second direction and intersecting the first strip 601, wherein the first direction is perpendicular to the second direction; and a third electrode 602 and a fourth electrode 604 formed at both ends of the second strip 606 and connected to the second strip 606.

[0044] exist Figure 6In the specific embodiment shown, the first strip 601 includes a first end 6012, a second end 6014, and a connecting portion 6016 located between the first end 6012 and the second end 6014. The end of the connecting portion 6014 connected to the first end 6012 or the second end 6014 is conical, which is beneficial for the distribution of magnetization. The second strip 606 includes a first arm 6062 and a second arm 6064. The first arm 6062 is located on one side of the first strip 601 and connected to the first strip 601; the second arm 6064 is located on the other side of the first strip 601 and connected to the first strip 601. The connecting portion 6016 is made of a magnetic material, and the part where the first strip 601 and the second strip 606 intersect is made of a magnetic material; the first arm 6062 and the second arm 6064 are made of a material with a higher electrical conductivity than the magnetic material; the first end 6012 and the second end 6014 are made of a material with a higher electrical conductivity than the magnetic material. The magnetic material layer of the connecting part 6016 is the same magnetic material layer as the magnetic material layer of the magnetoresistive strip 230 in the Wheatstone bridges 200a and 200b shown above. Alternatively, in a specific embodiment of this invention, the magnetic material layer in the anomalous Hall unit is the same magnetic material layer as the magnetic material layers in the first anisotropic magnetoresistive sensing unit and the second anisotropic magnetoresistive sensing unit.

[0045] Figure 6 The four electrodes of the anomalous Hall effect unit shown cannot be used in a clockwise or counterclockwise rotation as the power supply terminal VDD3, the first signal terminal V5, the ground terminal GND3, and the second signal terminal V6. Figure 6 In the specific embodiment shown, the two electrodes 603 and 605 of the first strip 601 are the power supply terminal VDD3 and the ground terminal GND3, respectively, and the two electrodes 602 and 604 of the second strip 606 are the first signal terminal V5 and the second signal terminal V6, respectively.

[0046] Please refer to Figure 7 As shown, this is one embodiment of the present invention. Figure 1 The diagram shows the structure of a single-chip triaxial magnetic sensor. Figure 7 In this context, a rectangular coordinate system is defined, where the x-axis extends from left to right and the y-axis extends from bottom to top. Figure 7 The single-chip triaxial magnetic sensor shown includes a first Wheatstone bridge 703, a second Wheatstone bridge 702, and an anomalous Hall element 701. The first Wheatstone bridge 703 and the second Wheatstone bridge 702 are connected to... Figure 2 The structure of the biaxial AMR sensor (or AMR bridge) shown is consistent; the anomalous Hall element 701 and Figure 6The structures of the anomalous Hall units shown are identical. Among them, the anomalous Hall unit 701 senses the Z-axis magnetic field Bz, the second Wheatstone bridge 702 senses the Y-axis magnetic field By, and the first Wheatstone bridge 703 senses the X-axis magnetic field Bx.

[0047] In summary, the single-chip triaxial magnetic sensor provided by this utility model has the following advantages:

[0048] 1. This utility model uses a planarization process to realize the detection of three-axis magnetic fields on the same chip, and the three-axis sensing units are implemented on the same layer.

[0049] 2. This utility model combines magnetoresistive technology with the anomalous Hall effect, and uses a completely planar process to manufacture the triaxial magnetic sensor, which reduces the difficulty of the manufacturing process.

[0050] In this utility model, words such as “connection,” “linked,” “connected,” and “joined” that indicate electrical connection, unless otherwise specified, indicate direct or indirect electrical connection.

[0051] The above description is only a preferred embodiment of the present utility model. The protection scope of the present utility model is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the disclosure of the present utility model should be included in the protection scope recorded in the claims.

Claims

1. A triaxial magnetic sensor, characterized in that, It includes: The first anisotropic magnetoresistive sensing unit is used to sense an external magnetic field in the X-axis direction to generate an X-axis sensing voltage, wherein the X-axis sensing voltage represents the magnetic field component in the X-axis direction of the sensed external magnetic field. The second anisotropic magnetoresistive sensing unit is used to sense an external magnetic field in the Y-axis direction to generate a Y-axis sensing voltage, wherein the Y-axis sensing voltage represents the magnetic field component of the sensed external magnetic field in the Y-axis direction, and the X-axis and Y-axis are orthogonal to each other. An anomalous Hall element is used to sense an external magnetic field in the Z-axis direction to generate a Z-axis sensing voltage, which represents the magnetic field component of the sensed external magnetic field in the Z-axis direction. The Z-axis is orthogonal to the X-axis and Y-axis. The signal processing circuit is electrically connected to the first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, and the anomalous Hall unit. The signal processing circuit is used to convert the X-axis sensed voltage into a magnetic field component in the X-axis direction of the external magnetic field, convert the Y-axis sensed voltage into a magnetic field component in the Y-axis direction of the external magnetic field, and convert the Z-axis sensed voltage into a magnetic field component in the Z-axis direction of the external magnetic field.

2. The triaxial magnetic sensor according to claim 1, characterized in that, The first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, the anomalous Hall unit, and the signal processing circuit are integrated into a single chip. The plane defined by the X-axis and Y-axis is parallel to the single-chip plane.

3. The triaxial magnetic sensor according to claim 2, characterized in that, The single chip includes a substrate, and a first structural layer and a second structural layer stacked on the substrate. The signal processing circuit is disposed in the first structural layer; The first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, and the anomalous Hall unit are disposed in the second structural layer; The first structural layer is located on the substrate; The second structural layer is located above the first structural layer.

4. The triaxial magnetic sensor according to claim 3, characterized in that, The single chip also includes an isolation layer and a third structural layer. The isolation layer is located between the first structural layer and the second structural layer. The via metal passes through the isolation layer to electrically connect the first anisotropic magnetoresistive sensing unit, the second anisotropic magnetoresistive sensing unit, and the anomalous Hall unit to the signal processing circuit. The third structural layer is located above the second structural layer. The third structural layer includes a protective layer and electrodes thereon. The electrodes are connected to the signal processing circuit through via metal.

5. The triaxial magnetic sensor according to claim 3, characterized in that, The first anisotropic magnetoresistive sensing unit includes a first Wheatstone bridge, which is used to sense an external magnetic field in the X-axis direction to generate an X-axis sensing voltage. The second anisotropic magnetoresistive sensing unit includes a second Wheatstone bridge, which is used to sense an external magnetic field in the Y-axis direction to generate a Y-axis sensing voltage. The first Wheatstone bridge and the second Wheatstone bridge are arranged orthogonally.

6. The triaxial magnetic sensor according to any one of claims 1-5, characterized in that, The anomalous Hall unit includes: The first strip extending along the first direction; A first electrode and a second electrode are respectively formed at both ends of the first strip portion and connected to the first strip portion; A second stripe extending along a second direction and intersecting with the first stripe, wherein the first direction is perpendicular to the second direction; The third electrode and the fourth electrode are respectively formed at both ends of the second strip and connected to the second strip.

7. The triaxial magnetic sensor according to claim 6, characterized in that, Both the first and second strip portions are made of magnetic material; the four electrodes of the anomalous Hall unit are, in clockwise or counterclockwise order, the power supply terminal, the first signal terminal, the ground terminal, and the second signal terminal.

8. The triaxial magnetic sensor according to claim 6, characterized in that, The first strip is made of magnetic material; The second strip-shaped portion includes a first arm and a second arm. The first arm is located on one side of the first strip-shaped portion and connected to the first strip-shaped portion. The second arm is located on the other side of the first strip-shaped portion and connected to the first strip-shaped portion. The portion where the first strip-shaped portion and the second strip-shaped portion intersect is made of the magnetic material. The first arm and the second arm are made of a material with a higher electrical conductivity than the magnetic material. The two electrodes of the first strip are the power supply terminal VDD and the ground terminal GND, respectively, and the two electrodes of the second strip are the first signal terminal and the second signal terminal, respectively.

9. The triaxial magnetic sensor according to claim 6, characterized in that, The first strip-shaped portion includes a first end, a second end, and a connecting portion located between the first end and the second end, wherein the end of the connecting portion that connects to the first end or the second end is tapered or semi-circular; The connecting part is made of a magnetic material, and the first end and the second end are made of a material with a higher electrical conductivity than the magnetic material. The second strip-shaped portion includes a first arm and a second arm. The first arm is located on one side of the first strip-shaped portion and connected to the first strip-shaped portion. The second arm is located on the other side of the first strip-shaped portion and connected to the first strip-shaped portion. The portion where the first strip-shaped portion and the second strip-shaped portion intersect is made of the magnetic material. The first arm and the second arm are made of a material with a higher electrical conductivity than the magnetic material. The two electrodes of the first strip are the power supply terminal VDD and the ground terminal GND, respectively, and the two electrodes of the second strip are the first signal terminal and the second signal terminal, respectively.

10. The triaxial magnetic sensor according to claim 1, characterized in that, The magnetic material layer in the anomalous Hall unit is the same magnetic material layer as the magnetic material layers in the first anisotropic magnetoresistive sensing unit and the second anisotropic magnetoresistive sensing unit.

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