An angle sensor assembly and an angle measurement method

Abstract

The present application relates to a kind of angle sensor assembly and angle measurement method, belong to angle measurement technical field.The angle sensor assembly of the present application, with stator component and the rotor component of arbitrary angle rotation relative to stator component, stator component includes four electrode parts using magnetic multilayer film is formed, rotor component is the annular magnet or cylindrical magnet along its diametric direction magnetization is formed.The measurement method of the present application is relative to the angle sensor stator component configuration rotatable magnetic source, in three-dimensional space rotation the rotor component, according to the position relationship of the rotor component with the angle sensor stator component, using abnormal Hall effect or tunnel magnetoresistance effect measurement resistance characteristic, in the Cartesian coordinate system under prior calibration, the angle of radial magnetic field generated by magnetic source is projected on three orthogonal planes, so as to be able to efficiently measure the rotation angle of magnetic source relative to angle sensor.

Description

Technical Field

[0001] This invention belongs to the field of angle measurement technology, and more specifically, relates to an angle sensor assembly and an angle measurement method. Background Technology

[0002] Angle sensors are commonly used geometric sensors with wide applications in many fields, including aerospace, industrial production, mechanical manufacturing, and military science. In recent years, with technological advancements, measurement needs have expanded from two-dimensional to three-dimensional. New robots, bioelectronics, and diagnostic systems all require various compact and high-performance sensors. Among these, compact angle sensors are needed to quickly and accurately determine the actual rotation angle of three-dimensional rotatable components (such as robot rotary joints) in three-dimensional space for easier operation.

[0003] Common angle sensors on the market mainly include resistive, capacitive, optical, and magnetic types, which generally determine the angle shift based on optical, electrical, or magnetic principles. Capacitive sensors are mainly made based on the principle of changes in the capacitance of a device, offering advantages such as low power consumption and high sensitivity. However, these sensors experience increased measurement errors or even failure in humid and greasy environments. Optical sensors offer high resolution, but their anti-interference capabilities are weak, making them difficult to operate in harsh environments. Furthermore, their manufacturing requirements and costs are high, limiting their widespread use. Among different types of angle position sensors, magnetic sensors are widely used due to their non-contact detection, stable performance, and low cost. Magnetic angle sensors are mainly divided into inductive, Hall effect, and magnetoresistive types. They sense changes in the magnetic field through a magnetic sensing element, and this conversion process usually corresponds to a certain angle relationship. They are stable, have a long lifespan, and high sensitivity, and can still function normally even in relatively harsh environments, making them one of the most widely used angle sensors currently. While inductive angle sensors are durable and highly resistant to harsh environments, they are bulky and expensive. While Hall effect angle sensors are relatively inexpensive, they suffer from low sensitivity in weak magnetic fields and significant thermal drift. Magnetoresistive angle sensors, including anisotropic magnetoresistive (AMR) angle sensors, giant magnetoresistive (GMR) sensors, and tunneling magnetoresistive (TMR) sensors, effectively bridge the gap between Hall effect and inductive sensors in terms of sensitivity, detection accuracy, and cost. With appropriate settings and supporting components, these magnetoresistive angle sensors can generate sine and cosine output signals relative to the direction of the external field in a saturated state; thus, they can achieve angle sensing functionality. Although their working principle is simple, obtaining distortion-free sine and cosine output signals requires specialized design and manufacturing processes, resulting in a relatively complex structure.

[0004] Furthermore, measuring angles in three-dimensional space using existing angle sensors is a challenging task. Most existing technologies can only perform measurements in two-dimensional space, while angle sensors that involve measuring angle changes in three-dimensional space place magnetic angle sensors on three orthogonal planes (x, y, z), involving simultaneous operation in multiple specific directions. This can easily lead to problems such as non-orthogonality of measurement directions and requires complex multi-device processing systems, which seriously affects the reliability and cost of the measurement system. Currently, there are no reports in the literature on measuring the rotational angle changes of rotatable parts in three-dimensional space using a single-device angle sensor.

[0005] In summary, existing angle sensors suffer from limitations in angle measurement, including limited measurement angles, low efficiency, and inaccurate results. Summary of the Invention

[0006] To address the aforementioned technical problems, the present invention aims to provide a single-device angle sensor capable of measuring the angle of rotation of a three-dimensional rotatable component in three-dimensional space, and a three-dimensional angle measurement method based on the SOT effect principle.

[0007] The present invention first provides an angle sensor assembly for measuring the three-dimensional rotation angle of a non-magnetic three-dimensional rotatable component. The angle sensor assembly includes a stator part and a rotor part that can rotate at any angle in three-dimensional space relative to the stator part.

[0008] The stator portion consists of four electrode sections and a cross-shaped connecting section. The four electrode sections are respectively connected to the four ends of the cross-shaped connecting section. Each of the four electrode sections is composed of an identical heterojunction magnetic multilayer film.

[0009] The rotor component is a ring-shaped magnet or a cylindrical magnet magnetized along its diameter direction;

[0010] The rotor component is used to be synchronously rotated and connected with the non-magnetic three-dimensional rotatable component.

[0011] According to one embodiment of the present invention, the heterojunction magnetic multilayer film includes: a Si substrate, and a spin flow generation layer, a magnetic material layer, an insulating layer and a top cap layer that are sequentially stacked on the Si substrate from bottom to top;

[0012] The material of the spin flow generation layer is a heavy metal or a topological insulator material capable of generating spin-polarized electrons; the magnetic material layer is a ferromagnetic magnetic material layer capable of perpendicular magnetization.

[0013] According to one embodiment of the present invention, the spin flow generation layer is a W heavy metal layer, the magnetic material layer is a CoFeB ferromagnetic thin film layer, the insulating layer is an MgO insulating layer, and the top cap layer is a Ta heavy metal layer.

[0014] According to one embodiment of the present invention, the heterojunction magnetic multilayer film used to form the electrode portion further includes an auxiliary layer located between the insulating layer and the top cap layer, the auxiliary layer including at least a non-magnetic dielectric layer and a magnetic fixing layer;

[0015] The material of the magnetic fixing layer is preferably a heterojunction magnetic material with a Curie temperature greater than 500K and a coercive field strength more than 10 times that of the magnetic material layer. When the material of the non-magnetic medium layer is MgO, Al2O3, or TiO2, the four electrode sections form an MTJ structure. When the material of the non-magnetic medium layer is non-magnetic Cu, Au, or Ag, the four electrode sections form a spin valve structure.

[0016] According to one embodiment of the present invention, the rotor component is used to connect with the non-magnetic three-dimensional rotatable component via gears or transmission rods and transmission shafts.

[0017] According to another aspect of the present invention, the present invention also provides an angle measurement method based on the above-described angle sensor assembly, comprising the following steps:

[0018] S1: The angle sensor assembly is calibrated in all directions using a magnetic field of known magnitude and direction;

[0019] S2: Apply current in the x, y and z directions of the stator section respectively to obtain the RH curves of the x magnetic field, y magnetic field and z magnetic field respectively. Then, perform linear fitting on the RH curves to obtain the slopes Kx, Ky, Kz and the corresponding bias value of each RH curve. In the RH curve, R is defined as resistance and H is defined as magnetic field vector.

[0020] S3: Place the stator portion on the x and y planes, and rotate the circular plane of the rotor component on the zx plane;

[0021] S4: Apply a positive current and a negative current of the same magnitude as the calibration current in the x-direction, and measure the voltage in the y-direction; apply a positive current and a negative current of the same magnitude as the calibration current in the y-direction, and measure the voltage in the x-direction. Calculate the rotation angle θ of the rotor component in the zx plane based on the positive and negative currents in the x and y directions, the measured voltage, the contribution values ​​RHx, RHy, and RHz of the RH curve in the xyz directions from step S2, and the corresponding bias values. H zx ;

[0022] S5: Rotate the circular plane of the rotor component in the xy and yz planes respectively, and repeat step S4 to obtain the rotation angle θ of the rotor component in the xy and yz planes respectively. H xy and θ H yz According to the θ H zx θ H xy and θ H yz The rotation angle of the rotor component in three-dimensional space is obtained, thereby measuring the rotation angle of the non-magnetic three-dimensional rotatable component.

[0023] According to one embodiment of the present invention, in step S1, the calibration process is as follows: from left to right, the first electrode, the second electrode, the third electrode and the fourth electrode of the angle sensor are arranged in sequence, with the direction from the first electrode to the third electrode as the positive x-axis direction, the direction from the second electrode to the fourth electrode as the positive y-axis direction, and the direction perpendicular to the xy plane upward as the positive z-axis direction.

[0024] According to one embodiment of the present invention, step S2 includes:

[0025] S2.1: A positive current and a negative current are passed through the stator in the x direction, a changing magnetic field is applied in the x direction, and the voltage across the stator is measured in the y direction. The voltage is then divided by the positive and negative currents to obtain the resistance R. The RH curves under the positive and negative currents in the x direction magnetic field are obtained and are respectively denoted as Rxy(+Ix)-Hx curve and Rxy(-Ix)-Hx curve.

[0026] S2.2: Subtract the obtained Rxy(+Ix)-Hx curve from the Rxy(-Ix)-Hx curve and divide by 2 to obtain the RHx-Hx curve. Perform linear fitting on the RHx-Hx curve to obtain the slope Kx of the RHx-Hx curve and the corresponding bias value.

[0027] S2.3: Apply positive and negative currents to the sensor in the y direction, apply a changing magnetic field in the y direction, measure the voltage across the sensor in the x direction, divide the obtained voltage by the positive and negative currents to obtain the resistance R, and obtain the RH curves under the positive and negative currents in the y direction magnetic field, which are respectively denoted as Ryx(+Iy)-Hy curve and Ryx(-Iy)-Hy curve.

[0028] S2.4: Subtract the obtained Ryx(+Iy)-Hy curve from the Ryx(-Iy)-Hy curve and divide by 2 to obtain the RHy-Hy curve. Perform linear fitting on the RHy-Hy curve to obtain the slope Ky of the RHx-Hx curve and the corresponding bias value.

[0029] S2.5: Apply positive and negative currents to the sensor in the x or y direction, apply a changing magnetic field in the z direction, measure the voltage across the sensor in the y or x direction, divide the obtained voltage by the positive and negative currents to obtain the resistance R, and obtain the R(I)-H curve under the positive current and magnetic field in the z direction, which are respectively denoted as Rxy(+Ix)-Hz(Ryx(+Iy)-Hz) and Rxy(-Ix)-Hz(Ryx(-Iy)-Hz).

[0030] S2.6: Add the obtained Rxy(+Ix)-Hz(Ryx(+Iy)-Hz) curve and Rxy(-Ix)-Hz(Ryx(-Iy)-Hz) curve and divide by 2 to obtain the RHz-Hz curve. Perform linear fitting on the RHz-Hz curve to obtain the slope Kz and the corresponding bias value.

[0031] According to one embodiment of the present invention, step S4 includes:

[0032] S4.1: Divide the measured voltages in the x and y directions by their respective positive and negative currents to obtain the resistance values ​​R1, R2, R3, and R4;

[0033] S4.2: The contribution value RHz of the magnetic field in the z direction to the resistance is calculated according to (R1+R2) / 2, and the contribution value RHx of the magnetic field in the x direction alone to the resistance is calculated according to (R1-R2) / 2. The contribution value RHz of the magnetic field in the z direction to the resistance can also be calculated according to (R3+R4) / 2.

[0034] S4.3: Subtract the corresponding bias values ​​from the contribution values ​​RHx and RHz, then divide by Kx and Kz from step S2 respectively, and then perform inverse trigonometric tangent processing to obtain the rotation angle θ of the rotor component in the zx plane. H zx .

[0035] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0036] (1) In the angle sensor assembly designed in this invention, the stator part is composed of four symmetrical electrode parts, so that the rotor part can rotate at any angle relative to the stator part in three-dimensional space without affecting the final measurement result, and the measurement range is very wide. This invention measures the radial magnetic field generated by the rotor part and uses the characteristics of measuring resistance by the anomalous Hall effect or tunnel magnetoresistance effect, thereby efficiently measuring the rotation angle of the rotor part relative to the stator part of the angle sensor, avoiding the problem of non-orthogonal measurement direction in three-dimensional space of the existing measurement system. Moreover, since the synchronous connection between the rotor part and the object to be measured is established, the rotation angle measurement result of the object to be measured can be directly obtained from the rotation angle of the rotor, thus achieving more efficient and accurate angle measurement.

[0037] (2) The preferred ferromagnetic thin film structure of the stator component of the present invention has good vertical magnetic anisotropy, which makes the angle sensor assembly have good repeatability, measurement durability and high measurement accuracy. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the angle sensor assembly provided in Embodiment 1 of the present invention, wherein the lower part is the stator component and the upper part is the rotor component.

[0039] Figure 2 This is an optical microscope image of the stator component provided in Embodiment 1 of the present invention.

[0040] Figure 3 This is a schematic diagram of the film structure of the stator component provided in Embodiment 1 of the present invention. The reference numerals are: substrate 1, spin flow generation layer 2, ferromagnetic material layer 3, insulating layer 4, and top cap layer 5.

[0041] Figure 4 The figures provided in Embodiment 1 of the present invention are RH curves under positive and negative currents when the stator component is energized in the x, y, and z directions and a magnetic field is applied. (a) is the RH curve of the stator component under positive and negative currents when the stator component is energized in the x direction and a magnetic field is applied only in the x direction; (b) is the RH curve of the stator component under positive and negative currents when the stator component is energized in the y direction and a magnetic field is applied only in the y direction; and (c) is the RH curve of the stator component under positive and negative currents when the stator component is energized in the x direction and a magnetic field is applied only in the z direction.

[0042] Figure 5 (a) shows the correspondence between the resistance value obtained by subtracting the anomalous Hall resistance value from the resistance value obtained by passing positive and negative currents in the x direction and dividing by 2, and the magnetic field component Hx in the x direction, as well as the fitted straight line, when a magnetic field is applied to the stator component alone in the x direction according to Embodiment 1 of the present invention. Figure 5(b) shows the correspondence between the resistance value obtained by subtracting the anomalous Hall resistance measured in the y-direction and dividing by 2 when a magnetic field is applied only to the stator component provided in Embodiment 1 of the present invention, and the magnetic field component Hy in the y-direction, as well as the fitted straight line. Figure 5 In Example 1 of this invention, (c) shows the relationship between the resistance value obtained by adding the anomalous Hall resistance measured in the x direction and dividing it by 2 when the stator component is subjected to a magnetic field in the z direction alone, and the magnetic field component Hz in the z direction, as well as the fitted straight line.

[0043] Figure 6 (a) is a schematic diagram showing the rotation angle of the radial magnetic field generated by a rotor component rotating in the zx plane in a three-dimensional Cartesian coordinate system, detected by the angle sensor assembly provided in Embodiment 1 of the present invention. Figure 6 (b) is a schematic diagram showing the rotation angle of the radial magnetic field generated by a rotor component rotating in the xy plane of a three-dimensional Cartesian coordinate system, detected by the angle sensor assembly provided in Embodiment 1 of the present invention. Figure 6 (c) is a schematic diagram of the rotation angle of the radial magnetic field generated by the rotor component rotating on the yz plane in the three-dimensional Cartesian coordinate system, which is detected by the angle sensor assembly provided in Embodiment 1 of the present invention.

[0044] Figure 7 In the diagrams (a), (b), and (c), the scatter plots and fitting curves of the signal output of the angle sensor assembly provided in Embodiment 1 of the present invention in the zx plane, xy plane, and yz plane are respectively.

[0045] Figure 8 In the figure, (a), (b), and (c) represent the angle errors between the measured and actual values ​​of the angle sensor assembly provided in Embodiment 1 of the present invention in the zx plane, xy plane, and yz plane. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this invention clearer, the 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 merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0047] The present invention will be further described below with reference to the accompanying drawings:

[0048] In the field of angle sensors, magnetic angle sensors are an important component because static magnetic fields can penetrate common obstacles, while optical, acoustic, and electrostatic fields are typically affected by reflection, absorption, and shielding effects. Furthermore, with technological advancements, sensors that detect changes in the angle of a magnetic field vector in a two-dimensional plane are no longer sufficient. Navigation, biomedicine, and industrial automation increasingly require angle sensors that can detect angle changes in three-dimensional magnetic field space. Currently, mainstream magnetic angle sensors can only measure angles in two dimensions, and even their measurement range is limited to 0° to 360°. In three-dimensional space, traditional sensors for measuring angle changes place a sensing unit on each of the three orthogonal axes, resulting in a complex electrical structure and a tendency for misalignment, requiring leveling and other adjustments. Compared to the above measurement methods, this invention proposes an angle sensor assembly and its usage method for detecting the angle change of a magnetic source in three-dimensional space based on a single angle sensor. Based on the SOT effect, it utilizes the AHE effect or TMR effect alone. When the position of the fixed device remains unchanged, the circular plane of the rotor component rotates in three-dimensional space, and the resistance is read using the AHE effect or TMR effect to achieve the angle measurement of the magnetic source in three-dimensional space.

[0049] The Hall effect in the magnetic material layer of a sensor comprises two parts: the normal Hall effect and the anomalous Hall effect (AHE). Existing research indicates that the signal generated by AHE in ferromagnetic materials is significantly greater than that generated by the normal Hall effect. Testing primarily focuses on the anomalous Hall effect (AHE). A test current is applied across the device's terminals, and the anomalous Hall voltage is measured at the other two terminals. The anomalous Hall resistance of the device can then be calculated. Based on the SOT effect, a spin current is generated to alter the magnetization state of the magnetic material layer. The resistance value, which changes due to the different magnetization states, is then read using the anomalous Hall effect. The TMR effect refers to the situation where, when the first ferromagnetic layer, the non-magnetic material layer, and the second ferromagnetic layer form an MTJ (Magnetic Tunnel Junction) or spin valve structure, the orientation of the second ferromagnetic layer is pinned, and the magnetization direction of the first ferromagnetic layer can be independently switched under the control of an external magnetic field based on the SOT effect. If the polarization directions of the two ferromagnetic layers are parallel, electrons are more likely to tunnel through the insulating layer, resulting in low resistance. Conversely, if the polarization directions are antiparallel, electrons are less likely to tunnel through the insulating layer, resulting in extremely high resistance. Therefore, this junction can switch between two resistance states: a high-resistance state and a low-resistance state. This electron tunneling effect can be used to read the resistance value of the device as a result of the different magnetization states of the first ferromagnetic layer.

[0050] In some embodiments, the angle sensor assembly includes a stator portion and a rotor portion rotatable relative to the stator portion; wherein the stator portion comprises four electrode portions and a cross-shaped connecting portion, the four electrode portions being respectively connected to the four ends of the cross-shaped connecting portion, and both the electrode portions and the cross-shaped connecting portion being composed of heterojunction magnetic multilayer films; the rotor portion is a circular annular magnet or a cylindrical magnet magnetized in its diametrical direction; the rotor portion is used for synchronous rotational connection with the non-magnetic three-dimensional rotatable component.

[0051] In some embodiments, the connection between the rotor component and the non-magnetic three-dimensional rotatable component includes, but is not limited to, mechanical connection via gears or a transmission rod and transmission shaft, as long as it ensures that the rotor component and the non-magnetic three-dimensional rotatable component rotate synchronously.

[0052] In some embodiments, the stator component consists of a spin flow generation layer, a magnetic material layer, an insulating layer, and a cap layer, arranged in a cross-shaped Hall Bar structure from bottom to top.

[0053] In some embodiments, the spin flow generation layer must be a heavy metal or a topological insulator material to generate spin-polarized electrons.

[0054] In some embodiments, the material used as the spin flow generation layer may be tantalum (Ta), platinum (Pt), tungsten (W), Bi2Se3, or Sb2Te3.

[0055] In some embodiments, the magnetic material layer is a ferromagnetic magnetic material that can be perpendicularly magnetized, such as CoFeB or Co.

[0056] In some embodiments, the insulating layer is an insulating material used to eliminate the influence of the spin current generated by the capping layer on the magnetic moment of the ferromagnetic layer. The material used as the insulating layer can be MgO or Al2O3.

[0057] In some embodiments, the capping layer is a metallic material used to protect the layers beneath it. The material of the capping layer can be tantalum (Ta) or titanium (Ti).

[0058] In some embodiments, the thickness of the ferromagnetic thin film layer is 0.8-1.5 nm, and the thickness of the insulating layer is 1-2.5 nm.

[0059] In some embodiments, an auxiliary layer is further included between the insulating layer and the top cap layer. The auxiliary layer includes at least a non-magnetic dielectric layer and a magnetic fixing layer. The magnetic fixing layer preferably has a heterojunction magnetic material layer with a Curie temperature greater than 500K and a coercive field strength more than 10 times that of the ferromagnetic thin film layer. When the non-magnetic dielectric layer is a metal oxide such as MgO, Al2O3, or TiO2, the electrode portion forms an MTJ structure. When the non-magnetic dielectric is a non-magnetic metal such as Cu, Au, or Ag, the electrode portion forms a spin valve structure.

[0060] In some embodiments, calibration can be performed as follows: the four terminals of the device are arranged in a counterclockwise order as the first electrode, second electrode, third electrode and fourth electrode of the device, with the direction from the first electrode to the third electrode initially as the x-axis direction, the direction from the second electrode to the fourth electrode as the y-axis direction, and the direction perpendicular to the xy plane upward as the z-axis direction.

[0061] In some embodiments, during the calibration process described above, a larger write current can be applied between the first and third electrodes or between the second and fourth electrodes. Due to the spin Hall effect, a spin current is generated in the spin current generation layer. The spin current, due to the SOT (Spin Hall Effect) acting on the magnetic domains of the magnetic material layer, changes their magnetization state. Simultaneously, the write operation is completed in conjunction with the thermal effect or the action of an external magnetic field. Correspondingly, a smaller read current is applied between the first and third electrodes or between the second and fourth electrodes. Correspondingly, the voltage is measured between the second and fourth electrodes or between the first and third electrodes, and the Hall resistance value is calculated to complete the read operation.

[0062] In some embodiments, the current density of the write current is greater than or equal to 10. 6 A / cm 2 The current density of the reading current is less than 10. 6 A / cm 2 .

[0063] In some embodiments, a large positive write current +Ix and a large negative current -Ix are applied to the first and third electrodes, respectively. Then, a small read current is applied between the first and third electrodes. The voltage is then measured between the second and fourth electrodes, and the anomalous Hall resistance values ​​Rxy(+Ix) and Rxy(-Ix) are calculated. Similarly, a large positive write current +Iy and a large negative write current -Iy are applied to the second and fourth electrodes, respectively. Then, a small read current is applied between the second and fourth electrodes, and the voltage is measured between the first and third electrodes, and the anomalous Hall resistance values ​​Ryx(+Iy) and Ryx(-Iy) are calculated. When the circular plane of the rotor component rotates in any plane in three-dimensional space, the above operations are performed to measure Rxy(+Ix), Rxy(-Ix), Ryx(+Iy), and Ryx(-Iy). The rotation angle of the magnetic source can be calculated from these data.

[0064] The following are specific examples:

[0065] Example 1

[0066] This invention provides an angle sensor assembly, such as... Figure 1-2 As shown, the angle sensor assembly includes a stator part and a rotor part that can rotate relative to the stator part. The stator part consists of four electrode parts and a cross-shaped connecting part. The four electrode parts are respectively connected to the four ends of the cross-shaped connecting part. The electrode parts are composed of heterojunction magnetic multilayer films. The rotor part is a ring magnet that forms a magnetic source in its diameter direction and is connected to the external robot elbow joint through a drive shaft and a drive rod (not specifically shown).

[0067] The film structure of ferromagnetic thin films is as follows Figure 3 As shown, the substrate 1 is a silicon wafer. A spin flow generation layer 2, a magnetic material layer 3, an insulating layer 4, and a top cap layer 5 are sequentially disposed on the substrate 1. The spin flow generation layer 2 is a heavy metal W layer, the strong magnetic material layer 3 is a CoFeB layer, the insulating layer 4 is an MgO insulating layer, and the top cap layer 5 is a Ta heavy metal layer, arranged in sequence.

[0068] In this embodiment, W is selected as the spin current generation layer to generate spin-polarized electrons. The thickness is 1 nm. The magnetic material layer is CoFeB, and the insulating material is MgO.

[0069] In this embodiment, the thickness of the ferromagnetic thin film layer is 0.8 nm, and the thickness of the insulating layer is 1 nm.

[0070] The top cap layer is made of metal (Ta) and is used to protect the layers beneath it, such as... Figure 3 As shown.

[0071] The fabrication method of the angle sensor component in this embodiment is as follows:

[0072] First, the ferromagnetic thin film was ultrasonically cleaned sequentially using acetone, ethanol, and deionized water. Then, photoresist was spin-coated onto the cleaned film using a spin coater, followed by pre-baking on a heated stage. After contact exposure using a UV lithography machine, development was performed using a developer to obtain the photolithographic pattern corresponding to the sensor structure. Ion beam etching was then used; areas covered by photoresist were unaffected by etching, while areas not covered by photoresist were etched down to the substrate. Finally, acetone was used to remove the photoresist from the device surface, resulting in a core size of 30 × 80 μm. 2 The dimensions of the four electrode sections are 100 × 100 μm. 2 Angle sensor, optical microscopic images of angle sensor devices such as Figure 2 As shown;

[0073] In actual production, mask templates corresponding to sensor arrays with different core dimensions and widths were designed, and individual sensor devices or sensor arrays were fabricated using micro-nano fabrication processes, such as... Figure 2 As shown, the core size of the sensor element is 30µm × 80µm, and the four electrodes designed outside the core area are 100µm × 100µm in size to form the product. After the device array is fabricated, the device is fixed on a ceramic test plate, and the four-terminal electrode leads are connected to an anomalous Hall effect testing system for anomalous Hall effect testing: First, a fixed magnetic field of a certain magnitude is applied to the device in any direction using an electromagnet. Then, a test current is passed through the two ends of the device, and the anomalous Hall voltage is measured at the other two ends. The anomalous Hall resistance (RH) of the device can be calculated. Generally, the Hall effect of magnetic materials includes two parts: the normal Hall effect and the anomalous Hall effect. In the testing of ferromagnetic materials, the signal generated by the AHE is much larger than the signal generated by the normal Hall effect. Moreover, the anomalous Hall resistance is only related to the material, temperature, and perpendicular magnetization. Therefore, when the material and temperature are constant, the anomalous Hall resistance is only related to the perpendicular magnetization. Thus, this characteristic can be used to characterize the magnetization state of the magnetic perpendicular film by measuring RH.

[0074] This embodiment also provides an angle measurement method for the angle sensor, including the following steps:

[0075] S1. The angle sensor is calibrated using a magnetic field of known magnitude and direction. The four ends of the spin flow generation layer, from left to right, are the first, second, third, and fourth electrodes of the sensor. The direction from the first electrode to the third electrode is the x-axis, the direction from the second electrode to the fourth electrode is the y-axis, and the direction perpendicular to the xy-plane upwards is the z-axis. Figure 1 As shown.

[0076] S2. Applying current to the angle sensor to obtain the RH curves of the individual x-magnetic field, individual y-magnetic field, and individual z-magnetic field includes the following steps:

[0077] S2.1. Place the angle sensor in a magnetic field where the magnitude of Hx changes and the direction is x. Apply positive and negative currents +Ix and -Ix in the x direction and measure its voltage in the y direction. Divide the voltage by the positive and negative currents to obtain the resistances Rxy(+Ix) and Rxy(-Ix), and obtain the curves of Rxy(+Ix)-Hx and Rxy(-Ix)-Hx under the positive and negative currents of the x magnetic field alone.

[0078] The range of the measured magnetic field is determined based on the coercivity of the device, that is, it varies within the range of positive and negative coercivity. First, an anomalous Hall effect curve is obtained by measuring within a large magnetic field range, and then the magnitude of the coercivity is determined from the curve, thereby determining the range of the scanning magnetic field.

[0079] The applied positive and negative current values ​​need to satisfy the condition that the measured anomalous Hall effect curve loops nearly coincide, while also being as small as possible to ensure low power consumption. In the step of determining the write current magnitude, the write current applied to the device gradually increases from small to large, which is reflected in the measured anomalous Hall effect curve loops so that the anomalous Hall effect curve loops in all directions nearly coincide.

[0080] S2.2. Subtract the Rxy(+Ix)-Hx curve obtained from the positive and negative current tests from the Rxy(-Ix)-Hx curve, i.e., RHx = (Rxy(+Ix) - Rxy(-Ix)) / 2. This yields the RHx-Hx curve. Linearly fit the obtained RHx-Hx curve for a single x-magnetic field to obtain its slope Kx and the bias value present in the curve.

[0081] S2.3. Place the angle sensor in a magnetic field where the magnitude of Hy changes and the direction is y. Apply positive and negative currents +Iy and -Iy in the y direction, and measure its voltage in the x direction. Divide the voltage by the positive and negative currents to obtain the resistances Ryx(+Iy) and Ryx(-Iy), and obtain the Ryx(+Iy)-Hy and Ryx(-Iy)-Hy curves under the positive and negative currents of the y magnetic field alone.

[0082] S2.4. Subtract the Ryx(+Iy)-Hy curve obtained from the positive and negative current tests from the Ryx(-Iy)-Hy curve, i.e., RHy = (Ryx(+Iy) - Ryx(-Iy)) / 2. This yields the RHy-Hy curve. Linearly fit the obtained RHy-Hy curve for a single y-magnetic field to obtain the curve slope Ky and the bias value present in the curve.

[0083] S2.5. Place the angle sensor in a magnetic field with a Hz magnitude variation and a z-direction direction. Apply positive and negative currents +Ix(+Iy) and -Ix(-Iy) in the x-direction (y-direction), and measure its voltage in the y-direction (x-direction). Divide the voltage by the positive and negative currents to obtain the resistances Rxy(+Ix)(Ryx(+Iy)) and Rxy(-Ix)(Ryx(-Iy)), thus obtaining the curves of Rxy(+Ix)-Hz(Ryx(+Iy)-Hz) and Rxy(-Ix)-Hz(Ryx(-Iy)-Hz) under the positive and negative currents of the z-magnetic field alone.

[0084] S2.6. Add the Rxy(+Ix)-Hz (Ryx(+Iy)-Hz) curves obtained from the tests under positive and negative currents to the Rxy(-Ix)-Hz (Ryx(-Iy)-Hz) curves, i.e., RHz = (Rxy(+Ix) + Rxy(-Ix)) / 2 (RHz = (Ryx(+Iy) + Ryx(-Iy)) / 2). This yields the RHz-Hz curve. Linearly fit the obtained RHz-Hz curve for a single z-magnetic field to obtain the curve slope Kz and the bias value of the curve.

[0085] The above calibration experiments yielded suitable +Ix, -Ix, +Iy, and -Iy, and the slopes of the RH curves for individual x-magnetic fields, individual y-magnetic fields, and individual z-magnetic fields were obtained as Kx, Ky, and Kz, respectively, along with the bias values ​​of the curves.

[0086] The resistance value varies depending on the structure of the angle sensor, and may be a Hall resistor, an MTJ, or a spin valve structure.

[0087] S3. In the coordinate system described in S1, rotate the circular plane of the rotor component relative to the zx plane of the stator component in the aforementioned spatial coordinate system;

[0088] S4. Apply positive and negative currents +Ix and -Ix of the same magnitude as the calibration current in the x-direction, and measure the voltage in the y-direction respectively; apply positive and negative currents +Iy and -Iy of the same magnitude as the calibration current in the y-direction, and measure the voltage in the x-direction respectively, to obtain the rotation angle θ of the rotor component in the zx plane. H zx , where θ H zx It is the angle between the radial magnetic field generated by the rotating magnetic source and the z-axis in the zx plane. The angle is positive when the direction of rotation and the axis follow the right-hand rule, and includes the following steps:

[0089] S4.1. Apply positive and negative currents +Ix and -Ix of the same magnitude as the calibration current in the x-direction, and measure the voltage in the y-direction respectively. Divide the voltage by the positive and negative currents to obtain the resistance values ​​R1 and R2; apply positive and negative currents +Iy and -Iy of the same magnitude as the calibration current in the y-direction, and measure the voltage in the x-direction respectively. Divide the voltage by the positive and negative currents to obtain the resistance values ​​R3 and R4.

[0090] S4.2. Based on the resistance values ​​R1, R2, R3 and R4, the contribution value RHz of the magnetic field in the z direction alone to the resistance is calculated according to RHz=(R1+R2) / 2, and the contribution value RHx of the magnetic field in the x direction alone to the resistance is calculated according to RHx=(R1-R2) / 2. The contribution value RHz of the magnetic field in the z direction alone to the resistance can also be calculated according to RHz=(R3+R4) / 2.

[0091] S4.3. Subtract the bias from step S2 from the calculated resistance contribution values ​​RHz and RHx of the magnetic field components in the z and x directions, respectively, then divide by Kz and Kx, and then perform inverse trigonometric function tangent processing. That is, when RHz≥0mΩ and RHx≥0mΩ, θ H zx =arctan(RHx / RHz), where θ H zx The range is 0° to 90°; when RHz < 0mΩ and RHx ≥ 0mΩ, θ H zx =arctan(RHx / RHz), where θ H zx The range is 90° to 180°; when RHz < 0 mΩ and RHx < 0 mΩ, θ H zx =arctan(RHx / RHz), where θ H zx The range is 180°~270°; when RHz≥0mΩ and RHx≤0mΩ, θ H zx =arctan(RHx / RHz), where θ H zx The range is 270° to 360°, from which the rotation angle θ of the rotor component on the zx plane is obtained. H zx .

[0092] S5. In the coordinate system described in S1, the circular plane of the rotor component rotates relative to the stator component in the xy and yz planes of the calibrated spatial coordinate system. The angle sensor remains fixed in the xy plane. Repeat step S4 to obtain the rotation angle θ of the rotor component in the xy and yz planes, respectively. Hxy and θ H yz ;where θ H xy θ is the angle between the radial magnetic field generated by the rotating rotor component and the x-axis in the xy plane; the angle is positive when the direction of rotation and the axis follow the right-hand rule. H yz This is the angle between the radial magnetic field generated by the rotating rotor component and the y-axis in the yz plane. The angle is positive when the direction of rotation and the axis follow the right-hand rule. It can be understood that when the radially magnetized rotor component rotates arbitrarily in three-dimensional space, the angle of the projection of the radial magnetic field generated by the magnetic source onto the three coordinate planes (zx plane, xy plane, yz plane) is measured through the above steps. This yields the rotation angle of the rotor component in three-dimensional space, and thus the actual rotation angle of the robot's elbow joint. The operation includes the following steps;

[0093] S5.1. Apply positive and negative currents +Ix and -Ix of the same magnitude as the calibration current in the x-direction, and measure the voltage in the y-direction respectively. Divide the voltage by the positive and negative currents to obtain the resistance values ​​R1 and R2; apply positive and negative currents +Iy and -Iy of the same magnitude as the calibration current in the y-direction, and measure the voltage in the x-direction respectively. Divide the voltage by the positive and negative currents to obtain the resistance values ​​R3 and R4.

[0094] S5.2. Based on the resistance values ​​R1, R2, R3 and R4, the contribution value RHx of the magnetic field in the x direction alone to the resistance is calculated according to RHx=(R1-R2) / 2, and the contribution value RHy of the magnetic field in the y direction alone to the resistance is calculated according to RHy=(R3-R4) / 2.

[0095] S5.3. Subtract the bias from step S2 from the calculated resistance contribution values ​​RHx and RHy of the magnetic field components in the x and y directions, respectively, then divide by Kx and Ky, and perform inverse trigonometric function tangent processing. That is, when RHx ≥ 0 mΩ and RHy ≥ 0 mΩ, θ H xy =arctan(RHy / RHx), where θ H xy The range is 0° to 90°; when RHx < 0 mΩ and RHy ≥ 0 mΩ, θ H xy =arctan(RHy / RHx), where θ H xy The range is 90° to 180°; when RHx < 0 mΩ and RHy < 0 mΩ, θ H xy =arctan(RHy / RHx), where θ H xyThe range is 180°~270°; when RHx≥0mΩ, RHy≤0mΩ, θ H xy =arctan(RHy / RHx), where θ H xy The range is 270° to 360°, from which the rotation angle θ of the rotor component in the xy plane is obtained. H xy .

[0096] S5.4. In the coordinate system described in S1, the circular plane of the rotor component is rotated relative to the yz plane of the calibrated spatial coordinate system of the angle sensor, while the angle sensor remains stationary in the xy plane. Step S4 is repeated. Based on the resistance values ​​R1, R2, R3, and R4, the contribution value RHz of the individual z-direction magnetic field to the resistance is calculated according to RHz = (R1 + R2) / 2, and the contribution value RHy of the individual y-direction magnetic field to the resistance is calculated according to RHy = (R3 - R4) / 2. The contribution value RHz of the individual z-direction magnetic field to the resistance can also be calculated according to RHz = (R3 + R4) / 2.

[0097] S5.5 Subtract the bias from step S2 from the calculated resistance contribution values ​​RHy and RHz of the magnetic field components in the y and z directions, respectively, then divide by Ky and Kz, and finally perform inverse trigonometric tangent processing. That is, when RHy ≥ 0 mΩ and RHz ≥ 0 mΩ, θ H yz =arctan(RHz / RHy), where θ H yz The range is 0° to 90°; when RHy < 0 mΩ and RHz ≥ 0 mΩ, θ H yz =arctan(RHz / RHy), where θ H yz The range is 90° to 180°; when RHy < 0 mΩ and RHz < 0 mΩ, θ H yz =arctan(RHz / RHy), where θ H yz The range is 180°~270°; when RHy≥0mΩ and RHz≤0mΩ, θ H yz =arctan(RHz / RHy), where θ H yz The range is 270° to 360°, from which the rotation angle θ of the rotor component in the yz plane is obtained. H yz .

[0098] Based on θ in S4-S5H zx θ H xy and θ H yz The rotation angle of the rotor component in three-dimensional space is obtained, thereby measuring the rotation angle of the non-magnetic three-dimensional rotatable component.

[0099] Test Results and Discussion

[0100] Figure 4 The figures provided in Embodiment 1 of the present invention show the RH curves under positive and negative currents when current flows in the x-direction and a magnetic field is applied only in the x-direction or z-direction alone, and the RH curves under positive and negative currents when current flows in the y-direction and a magnetic field is applied only in the y-direction alone. The magnetic field transitions from positive to negative and back to positive for one curve cycle. Figure 4 As shown, when a magnetic field Hx is applied solely in the x-direction, a current density of ±3.2 MA / cm is applied in the x-direction. 2 The current was measured, and then the curves of its resistance changing with the magnetic field were obtained. It was found that the two are symmetrical and opposite, and that under the application of positive or negative current, the curve of the magnetic field from positive to negative coincides with the curve of the magnetic field from negative to positive. Figure 4 As shown in (a). When a magnetic field Hy is applied alone in the y-direction, a current density of ±3.2 MA / cm is applied in the y-direction. 2 The current was measured, and then the curves of its resistance changing with the magnetic field were obtained. It was found that the two are symmetrical and opposite, and that under the application of positive or negative current, the curve of the magnetic field from positive to negative coincides with the curve of the magnetic field from negative to positive. Figure 4 As shown in (b). When a magnetic field of Hz is applied only in the z-direction, a current density of ±3.2 MA / cm is applied in the x-direction. 2 The current was measured, and then the curves of its resistance changing with the magnetic field were obtained. It was found that the two curves coincided, and that under the application of positive or negative current, the curves of the magnetic field from positive to negative coincided with the curves of the magnetic field from negative to positive. Figure 4 As shown in (c). That is, when only a magnetic field Hz is applied in the z direction, the resistance remains unchanged under the same positive and negative current; when only a magnetic field Hx is applied in the x direction, the resistance takes the opposite value under the same positive and negative current; when only a magnetic field Hy is applied in the y direction, the resistance takes the opposite value under the same positive and negative current.

[0101] Through testing and theoretical analysis, it was found that when the magnetic source rotates arbitrarily in three-dimensional space, the magnetic field H generated by the source consists of two in-plane magnetic field components (Hx or Hy) and one out-of-plane magnetic field component (Hz). When Hz is applied, the change in RH caused by Hz does not change with the direction of the writing current, but only with the direction of the applied magnetic field. Under the action of the writing current, the planar magnetic field component parallel to the current will change the sign of RH when the polarity of the writing current changes or the direction of the magnetic field changes. Therefore, by applying a current density of 3.2 MA / cm in the x-direction... 2 The positive and negative polarity of the writing current and the current density applied in the y direction are 3.2 MA / cm 2 The writing current with positive and negative polarities is determined through mathematical calculations, such as... Figure 5 As shown, the magnetic field components in the x, y, and z directions and their respective contributions to the anomalous Hall resistance RHx, RHy, and RHz can be calculated. It can be seen that the magnitudes of the magnetic fields in the three orthogonal directions are linearly related to their respective contributions to the anomalous Hall resistance. The points represent the actual measured points, and the solid line represents the fitted curve. It can be seen that the measured points and the fitted line fit well, and the fitting result R... 2 All are above 0.998, and the curves of the magnetic field from positive to negative and from negative to positive coincide with each other.

[0102] Figure 6 This diagram illustrates the angle measurement of the rotor component of the device rotating in three-dimensional space on three coordinate planes (zx plane, xy plane, yz plane). The four ends of the device are arranged counterclockwise as the first electrode, second electrode, third electrode, and fourth electrode. A three-dimensional Cartesian coordinate system is established with the initial direction of the first electrode pointing towards the third electrode as the x-axis, the direction of the second electrode pointing towards the fourth electrode as the y-axis, and the direction perpendicular to the xy plane upwards as the z-axis. Figure 6 (a) The device is fixed in the xy plane, and the circular plane of the rotor component rotates in the zx plane, θ H zx Let be the angle between the radial magnetic field generated by the magnetic source in the zx plane and the z-axis. When the direction of rotation follows the right-hand rule, the angle is positive. Figure 6 (b) The device is fixed in the xy plane, while the circular plane of the rotor component rotates in the xy plane, θ H xy The angle between the radial magnetic field generated by the magnetic source in the xy plane and the x-axis is positive when the direction of rotation follows the right-hand rule. Figure 6 (c) The device is fixed in the xy plane, and the circular plane of the rotor component rotates in the yz plane, θ H yz The angle between the radial magnetic field generated by the magnetic source in the yz plane and the y-axis is positive when the direction of rotation follows the right-hand rule.

[0103] Taking the rotor component of Example 1, which generates a radial magnetic field of 15 Oe, the sensor output diagram when the circular plane of the rotor component rotates on three coordinate planes (zx plane, xy plane, yz plane) is shown in the figure. Figure 7 As shown. Figure 7 (a) With the device stationary, the circular plane of the rotor component rotates in the zx plane of the calibrated spatial coordinate system. Positive and negative write currents are applied in the x and y directions respectively to calculate the anomalous Hall resistance contributed by the magnetic fields in each direction, resulting in the output curves RHx and RHz. It can be seen that both exhibit sine and cosine variations, with the solid line in the figure representing the fitted curve. The measured curve and the fitted curve fit each other well. 2 All are above 0.998. Similarly, Figure 7 (b) and Figure 7 (c) The output curves are obtained by rotating the circular plane of the rotor component in the xy and yz planes of the calibrated spatial coordinate system with the device stationary, and applying positive and negative write currents in the x and y directions respectively. The output curves fit the sine and cosine fitting curves well. R 2 It is also above 0.998. Figure 8 (a) Δθ H zx This is the difference between the rotation angle of the magnetic source in the zx plane measured by the sensor and the actual rotation angle. We can see that the measurement error angle fluctuates, but remains within 1°. Similarly... Figure 8 (b) and Figure 8 (c) is the difference Δθ between the rotation angle of the magnetic source in the xy and yz planes measured by the sensor and the actual rotation angle. H xy With Δθ H yz The error remains within 1° as the actual rotation angle changes, proving that the sensor can achieve high-precision angle sensing in three coordinate planes within a three-dimensional Cartesian coordinate system. This means that as long as the magnitude of the radial magnetic field generated by the magnetic source is within the range of the magnetic field that the device can sense, the aforementioned angle sensing can be achieved. Furthermore, when the magnetic source is not in any of the aforementioned planes but rotates at any position, the radial magnetic field generated by the magnetic source can be decomposed into the xy plane, yz plane, and zx plane, and the angle of its projection on these three planes can be calculated to achieve angle sensing.

[0104] The table below compares current angle sensors with the angle sensor of this embodiment. This embodiment compares all mainstream categories of angle sensors. Compared with existing angle sensors, as shown in Table 1, although their measurement accuracy is acceptable, they all have multi-device structures, relatively complex electrical structures, high manufacturing difficulty and cost, and can only measure the rotation angle of the component under test in two dimensions. In summary, current angle sensor assemblies generally suffer from the problem of cross-sensitivity between measurement axes, which seriously affects their ability to achieve high spatial resolution and miniaturization.

[0105] In contrast, it is clear from Table 1 that the single-device angle sensor in Embodiment 1, combined with SOT technology, advantageously achieves planarization and miniaturization of the single-device angle sensor while maintaining high accuracy. In further practical applications, TMR technology can replace the existing AHE as the readout method. This allows for a larger resistance change, resulting in higher sensitivity and accuracy, as the resistance change in TMR (several kΩ) is much larger than that in AHE (hundreds of mΩ). Therefore, a larger voltage change (IΔR) will be obtained, significantly improving resolution and measurement accuracy.

[0106] Table 1 compares the performance of the angle sensor assembly in Example 1 with existing angle sensor assemblies.

[0107] Table 1

[0108]

[0109]

[0110] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for measuring the angle of an angle sensor assembly, characterized in that, An angle sensor assembly is used to measure the three-dimensional rotation angle of a non-magnetic three-dimensional rotatable component. The angle sensor assembly includes a stator part and a rotor part that can rotate at any angle in three-dimensional space relative to the stator part. The stator portion consists of four electrode sections and a cross-shaped connecting section. The four electrode sections are respectively connected to the four ends of the cross-shaped connecting section. Each of the four electrode sections is composed of an identical heterojunction magnetic multilayer film. The rotor component is a ring-shaped magnet or a cylindrical magnet magnetized along its diameter direction; The rotor component is used to be synchronously rotated and connected with the non-magnetic three-dimensional rotatable component. The angle measurement method includes the following steps: S1: The angle sensor assembly is calibrated in all directions using a magnetic field of known magnitude and direction; S2: Apply current in the x, y and z directions of the stator section respectively to obtain the RH curves of the x magnetic field, y magnetic field and z magnetic field respectively. Then, perform linear fitting on the RH curves to obtain the slopes Kx, Ky, Kz and the corresponding bias value of each RH curve. In the RH curve, R is defined as resistance and H is defined as magnetic field vector. S3: Place the stator portion on the x and y planes, and rotate the circular plane of the rotor component on the zx plane; S4: Apply a positive current and a negative current of the same magnitude as the calibration current in the x-direction, and measure the voltage in the y-direction; apply a positive current and a negative current of the same magnitude as the calibration current in the y-direction, and measure the voltage in the x-direction. Calculate the rotation angle θ of the rotor component in the zx plane based on the positive and negative currents in the x and y directions, the measured voltage, the contribution values ​​RHx, RHy, and RHz of the RH curve in the xyz directions from step S2, and the corresponding bias values. H zx ; S5: Rotate the circular plane of the rotor component in the xy and yz planes respectively, and repeat step S4 to obtain the rotation angle θ of the rotor component in the xy and yz planes respectively. H xy and θ H yz According to the θ H zx θ H xy and θ H yz The rotation angle of the rotor component in three-dimensional space is obtained, thereby measuring the rotation angle of the non-magnetic three-dimensional rotatable component.

2. The angle measurement method according to claim 1, characterized in that, In step S1, the omnidirectional calibration is as follows: from left to right, the first electrode, the second electrode, the third electrode, and the fourth electrode of the angle sensor are arranged in sequence, with the direction from the first electrode to the third electrode as the positive x-axis direction, the direction from the second electrode to the fourth electrode as the positive y-axis direction, and the direction perpendicular to the xy plane and upward as the positive z-axis direction.

3. The angle measurement method according to claim 1, characterized in that, Step S2 includes: S2.1: A positive current and a negative current are passed through the stator in the x direction, a changing magnetic field is applied in the x direction, and the voltage across the stator is measured in the y direction. The voltage is then divided by the positive and negative currents to obtain the resistance R. The RH curves under the positive and negative currents in the x direction magnetic field are obtained and are respectively denoted as Rxy(+Ix)-Hx curve and Rxy(-Ix)-Hx curve. S2.2: Subtract the obtained Rxy(+Ix)-Hx curve from the Rxy(-Ix)-Hx curve and divide by 2 to obtain the RHx-Hx curve. Perform linear fitting on the RHx-Hx curve to obtain the slope Kx of the RHx-Hx curve and the corresponding bias value. S2.3: Apply positive and negative currents to the sensor in the y direction, apply a changing magnetic field in the y direction, measure the voltage across the sensor in the x direction, divide the obtained voltage by the positive and negative currents to obtain the resistance R, and obtain the RH curves under the positive and negative currents in the y direction magnetic field, which are respectively denoted as Ryx(+Iy)-Hy curve and Ryx(-Iy)-Hy curve. S2.4: Subtract the obtained Ryx(+Iy)-Hy curve from the Ryx(-Iy)-Hy curve and divide by 2 to obtain the RHy-Hy curve. Perform linear fitting on the RHy-Hy curve to obtain the slope Ky of the RHx-Hx curve and the corresponding bias value. S2.5: Apply positive and negative currents to the sensor in the x or y direction, apply a changing magnetic field in the z direction, measure the voltage across the sensor in the y or x direction, divide the obtained voltage by the positive and negative currents to obtain the resistance R, and obtain the R(I)-H curve under the positive current and magnetic field in the z direction, which are respectively denoted as Rxy(+Ix)-Hz (Ryx(+Iy)-Hz) and Rxy(-Ix)-Hz (Ryx(-Iy)-Hz) curves; S2.6: Add the obtained Rxy(+Ix)-Hz(Ryx(+Iy)-Hz) curve and Rxy(-Ix)-Hz(Ryx(-Iy)-Hz) curve and divide by 2 to obtain the RHz-Hz curve. Perform linear fitting on the RHz-Hz curve to obtain the slope Kz and the corresponding bias value.

4. The angle measurement method according to claim 1, characterized in that, Step S4 includes: S4.1: Divide the measured voltages in the x and y directions by their respective positive and negative currents to obtain the resistance values ​​R1, R2, R3, and R4; S4.2: According to The contribution value RHz of the magnetic field in the z-direction to the resistance was calculated, based on... The contribution value RHx of the magnetic field in the x-direction alone to the resistance is calculated, where it can also be obtained from... The contribution value RHz of the magnetic field in the z-direction to the resistance was calculated. S4.3: Subtract the corresponding bias values ​​from the contribution values ​​RHx and RHz, then divide by Kx and Kz from step S2 respectively, and then perform inverse trigonometric tangent processing to obtain the rotation angle θ of the rotor component in the zx plane. H zx .

5. The angle measurement method according to claim 1, characterized in that, The heterojunction magnetic multilayer film includes: a Si substrate, and a spin flow generation layer, a magnetic material layer, an insulating layer and a top cap layer that are stacked and grown sequentially from bottom to top on the Si substrate. The material of the spin flow generation layer is a heavy metal or a topological insulator material capable of generating spin-polarized electrons; the magnetic material layer is a ferromagnetic magnetic material layer capable of perpendicular magnetization.

6. The angle measurement method according to claim 5, characterized in that, The spin flow generation layer is a W heavy metal layer, the magnetic material layer is a CoFeB ferromagnetic thin film layer, the insulating layer is an MgO insulating layer, and the top cap layer is a Ta heavy metal layer.

7. The angle measurement method according to claim 5 or 6, characterized in that, The heterojunction magnetic multilayer film used to form the electrode portion further includes an auxiliary layer located between the insulating layer and the top cap layer, the auxiliary layer including at least a non-magnetic dielectric layer and a magnetic fixing layer; The material of the magnetic fixing layer is preferably a heterojunction magnetic material with a Curie temperature greater than 500K and a coercive field strength more than 10 times that of the magnetic material layer. When the material of the non-magnetic medium layer is MgO, Al2O3, or TiO2, the four electrode sections form an MTJ structure. When the material of the non-magnetic medium layer is non-magnetic Cu, Au, or Ag, the four electrode sections form a spin valve structure.

8. The angle measurement method according to claim 1, characterized in that, The rotor component is used to connect with the non-magnetic three-dimensional rotatable component via gears or transmission rods and transmission shafts.

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