Magnetic field sensor and method for measuring the same

Abstract

SOLUTION: The invention discloses a magnetic field sensor and a method for measuring the same. The magnetic field sensor includes a ground wire, a substrate and a half-wavelength resonator. The ground wire, the substrate and the half-wavelength resonator are sequentially stacked in a thickness direction of the magnetic field sensor. The half-wavelength resonator includes a conductor segment and a magnetoresistive element. The magnetoresistive element is positioned at a center position of the conductor segment; and the conductor section comprises a first conductor segment and a second conductor segment. Both sides of the magnetoresistive element contact the first and second conductor segments, respectively, and the magnetoresistive element is electrically connected to the first and second conductor segments; and the first conductor segment, the magnetoresistive element and the second conductor segment are successively arranged in a length direction of the magnetic field sensor.EFFECT: The sensitivity and accuracy of the magnetic field sensor can be improved.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to the technical field of magnetic field sensors, and in particular to a magnetic field sensor and a measurement method thereof. [Background technology]

[0002] Magnetic field sensors are widely used in consumer electronics and industrial manufacturing. In particular, magnetic field sensors are playing an increasingly important role in the Internet of Things (IoT) and Industrial Internet of Things (IIoT). Magnetic field sensors with magnetoresistance (MR) elements are already widely used. The resistance of a magnetoresistance element changes with changes in the external magnetic field experienced by the magnetoresistance element. Magnetoresistance elements include semiconductor magnetoresistance elements and metal magnetoresistance elements. Metal magnetoresistance element magnetic field sensors are widely popular due to their superior sensitivity, response speed, and reliability. However, because metal magnetoresistance elements are themselves conductors, it is difficult to accurately measure changes in the resistivity of the metal magnetoresistance element. Therefore, there is room for further improvement in the sensitivity and accuracy of magnetic field sensors. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention provides a magnetic field sensor and a measurement method thereof that can improve the sensitivity and accuracy of the magnetic field sensor. [Means for solving the problem]

[0004] According to one aspect of the present invention, a ground line, a substrate, and a half-wave resonator, which are laminated in this order along the thickness direction of the magnetic field sensor; The half-wave resonator comprises a conductor segment having a first conductor segment and a second conductor segment, and a magnetoresistive element located at a center position of the conductor segment, both sides of the magnetoresistive element contacting the first conductor segment and the second conductor segment, respectively, and electrically connected to the first conductor segment and the second conductor segment, respectively, and the first conductor segment, the magnetoresistive element, and the second conductor segment are sequentially arranged along the longitudinal direction of the magnetic field sensor. A magnetic field sensor is provided.

[0005] Preferably, the thickness of the magnetoresistive element and the conductor segment are the same, or the thickness of the magnetoresistive element is greater than the thickness of the conductor segment, or the thickness of the magnetoresistive element is less than the thickness of the conductor segment.

[0006] Preferably, the width of the magnetic resistance element is smaller than the width of the conductor segment, wherein the first conductor segment and the second conductor segment both have a first portion and a transition portion located on the side of the first portion closer to the magnetic resistance element, the width of which gradually changes from the width of the first portion to the width of the magnetic resistance element, wherein the width of the magnetic resistance element and the width of the conductor segment are both dimensions along the width direction of the magnetic field sensor, and the width direction of the magnetic field sensor and the length direction of the magnetic field sensor are perpendicular to each other.

[0007] Preferably, the half-wave resonator is "U" shaped.

[0008] Preferably, the magnetic field sensor comprises: The magnetoresistive element further includes a protective layer positioned on the side of the magnetoresistive element farther from the substrate and covering the magnetoresistive element.

[0009] Preferably, the magnetoresistive element is a metal magnetoresistive element; The metal magnetoresistive element includes one of a giant magnetoresistive element, a tunneling magnetoresistive element, and an anisotropic magnetoresistive element.

[0010] Preferably, the half-wave resonator is a planar transmission line; The planar transmission line includes one of a stripline, a microstripline, and a coplanar line.

[0011] According to another aspect of the present invention, A magnetic field sensor according to any one of the embodiments of the present invention is employed, Obtaining a calibration curve between the quality factor of the magnetic field sensor and the magnetic field strength; Obtaining a quality factor measurement of a magnetic field sensor; determining a to-be-measured magnetic field strength of the magnetic field sensor based on the calibration curve and the quality factor measurement; A method for measuring a magnetic field sensor is provided.

[0012] Preferably, obtaining a quality factor measurement of the magnetic field sensor comprises: determining a resonant frequency and a bandwidth of the magnetic field sensor by coupling between at least one coupling unit, the transmission impedance of which is the same as the characteristic impedance of the external measurement line, and the half-wave resonator; and determining a quality factor measurement of the magnetic field sensor based on the resonant frequency and bandwidth of the magnetic field sensor.

[0013] Preferably, the coupling between the coupling unit and the half-wave resonator includes one of a parallel coupling, an end-to-end coupling, and an electrical connection coupling. [Effects of the Invention]

[0014] A magnetic field sensor according to a technical aspect of an embodiment of the present invention includes a ground wire, a substrate, and a half-wavelength resonator stacked in sequence along the thickness direction of the magnetic field sensor, the half-wavelength resonator including a conductor segment having a first conductor segment and a second conductor segment, and a magnetoresistive element located at the center of the conductor segment, the magnetoresistive element contacting the first conductor segment and the second conductor segment at both ends and electrically connected to the first conductor segment and the second conductor segment, respectively, the first conductor segment, the magnetoresistive element, and the second conductor segment being sequentially arranged along the length direction of the magnetic field sensor. The magnetoresistive element being located at the center of the conductor segment allows the magnetoresistive element to be located at the point of maximum current and become more sensitive to changes in resistance due to changes in current, thereby more sensitively determining changes in loss and quality factor of the magnetoresistive element. Furthermore, the strength of the external magnetic field can be obtained based on the change in the quality factor of the magnetic field sensor, thereby improving the sensitivity of the magnetic field sensor. Furthermore, a calibration curve between the quality factor and the magnetic field can be determined based on the change in resistance of the magnetoresistive element in the magnetic field. By measuring the quality factor and substituting the measured quality factor into the calibration curve between the quality factor and the magnetic field, the magnitude of the current magnetic field can be accurately measured, and the sensitivity and accuracy of the magnetic field sensor can be improved.

[0015] It should be understood that the content described in this section is not intended to identify key or critical features of embodiments of the invention, nor is it intended to limit the scope of the invention. Other features of the invention will become more readily apparent from the following specification. [Brief explanation of the drawings]

[0016] In order to more clearly explain the technical aspects of the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. However, the drawings described below are only some embodiments of the present invention, and it is obvious that a person skilled in the art can further obtain other drawings according to these drawings without paying any creative labor.

[0017] [Figure 1] 1 is a structural schematic diagram of a magnetic field sensor according to Example 1 of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along the line AA′ in FIG. [Figure 3] 3 is a schematic diagram of a current distribution along the length direction of the half-wave resonator according to the first embodiment of the present invention. FIG. [Figure 4] FIG. 3 is a diagram showing the relationship between the quality factor of the magnetic field sensor according to the first embodiment of the present invention and the resistivity of the magnetoresistive element. [Figure 5] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 6] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 7] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 8] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 9] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 10] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 11] FIG. 4 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. [Figure 12] 10 is a flowchart of a measurement method of a magnetic field sensor according to Example 2 of the present invention. [Figure 13] FIG. 10 is a structural schematic diagram of a magnetic field sensor including a coupling unit according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] In order to allow those skilled in the art to better understand the aspects of the present invention, the following will clearly and completely describe the technical aspects of the embodiments of the present invention with reference to the drawings in the embodiments of the present invention, but it is clear that the described embodiments are only some embodiments of the present invention and do not represent all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without any creative work shall fall within the protection scope of the present invention.

[0019] It should be noted that the terms "first," "second," etc., used herein are not necessarily used to describe a particular order or chronology, but are merely used to distinguish between similar objects. Data used in this manner may be interchanged where appropriate, and it should be understood that the embodiments of the present invention described herein may be practiced in orders other than those illustrated or described herein. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover non-exclusive inclusions; for example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those explicitly recited steps or units, but may include other steps or units that are not explicitly recited or that are inherent to the process, method, product, or apparatus.

[0020] Example 1 An embodiment of the present invention provides a magnetic field sensor. FIG. 1 is a structural schematic diagram of the magnetic field sensor according to the first embodiment of the present invention. FIG. 2 is a schematic diagram of a cross section taken along the cutting line AA' in FIG. 1. Referring to FIGS. 1 and 2, the magnetic field sensor comprises a ground wire 30, a substrate 20, and a half-wavelength resonator 10. The ground wire 30, the substrate 20, and the half-wavelength resonator 10 are sequentially stacked along the thickness direction Y of the magnetic field sensor. The half-wavelength resonator 10 comprises a conductor segment and a magnetoresistive element 12. The magnetoresistive element 12 is located at the center of the conductor segment. The conductor segment comprises a first conductor segment 11 and a second conductor segment 13. Both sides of the magnetoresistive element 12 contact the first conductor segment 11 and the second conductor segment 13, respectively. The magnetoresistive element 12 is electrically connected to the first conductor segment 11 and the second conductor segment 13, respectively. The first conductor segment 11, the magnetoresistive element 12, and the second conductor segment 13 are sequentially arranged along the length direction X of the magnetic field sensor.

[0021] Here, the material of the ground line 30 is a highly conductive metal, including, but not limited to, gold, silver, copper, or a combination thereof. The ground line 30 may be a single-layer metal structure or a multi-layer structure, and the present invention is not specifically limited thereto. The substrate 20 is made of a low-loss dielectric material, including, but not limited to, silicon, gallium arsenide, FR-4, alumina, sapphire, quartz, or a combination thereof. The conductor segments, coupling unit, and ground line may be made of a non-magnetic material. The half-wavelength resonator 10 may be a transmission line, and the length of the half-wavelength resonator 10 is approximately half the wavelength corresponding to its fundamental mode resonant frequency. The specific length of the half-wavelength resonator 10 may vary slightly depending on the specific structure of the half-wavelength resonator 10. For example, the half-wavelength resonator 10 may be a planar transmission line, such as a stripline, a microstripline, or a coplanar line. The material of the conductor segments may be a highly conductive metal, including, but not limited to, gold, silver, copper, or a combination thereof. The half-wave resonator 10 may have a single-layer structure or a multi-layer structure. The magnetoresistance element 12 may be a metal magnetoresistance element, and for example, the magnetoresistance element 12 may be one of a giant magnetoresistance (GMR) element, a tunnel magnetoresistance (TMR) element, and an anisotropy of magnetoresistance (AMR) element. The embodiment of the present invention does not specifically limit the shape and structure of the magnetoresistance element 12. The magnetoresistance element 12 is electrically connected to the conductor segment.

[0022] Specifically, when an external magnetic field is applied to the magnetoresistive element 12, the resistivity of the magnetoresistive element 12 changes, thereby changing the quality factor (Q factor) of the half-wavelength resonator 10 included in the magnetic field sensor. From the above, the strength of the external magnetic field can be obtained based on the change in the Q factor of the magnetic field sensor. FIG. 3 is a schematic diagram of the current distribution along the length of the half-wavelength resonator according to the first embodiment of the present invention. Referring to FIG. 3, the X-axis represents the length of the half-wavelength resonator 10, i.e., the length of the magnetic field sensor. If the half-wavelength resonator 10 is a transmission line, the X-axis represents the length of the transmission line, and the I-axis represents the current at different positions of the half-wavelength resonator 10. When the half-wavelength resonator 10 is in fundamental mode resonance, the current at both ends is zero, and the current reaches a maximum value Imax at the center of the half-wavelength resonator 10. The magnetoresistive element 12 is located at the point where the fundamental mode current of the half-wavelength resonator 10 is maximum, i.e., the magnetoresistive element 12 is located at the center of the half-wavelength resonator 10. Therefore, the change in resistance of the magnetoresistive element 2 due to the applied magnetic field has the greatest effect on the loss during fundamental mode resonance of the half-wave resonator 10, and can also affect the Q factor of the half-wave resonator 10. The magnetoresistive element 12 is located at the point of maximum current and can be more sensitive to changes in resistance due to changes in current, so that the change in loss of the magnetoresistive element 12 and the change in Q factor can be more sensitively determined, and further, the strength of the external magnetic field can be obtained based on the change in the Q factor of the magnetic field sensor, thereby improving the sensitivity of the magnetic field sensor.

[0023] FIG. 4 is a diagram illustrating the relationship between the quality factor of a magnetic field sensor according to a first embodiment of the present invention and the resistivity of a magnetoresistive element. The magnetic field sensor in FIG. 4 is implemented using a microstrip line, and the characteristic impedance of the microstrip line is 50Ω. As the resistivity of the magnetoresistive element increases, the quality factor of the magnetic field sensor decreases monotonically. Therefore, the resistivity of the magnetoresistive element 12 can be estimated based on the quality factor, and the strength of the applied magnetic field can be estimated based on the resistivity of the magnetoresistive element 12. For example, the quality factor in the present embodiment may be a fundamental mode quality factor, which can be divided into a loaded fundamental mode quality factor and an unloaded fundamental mode quality factor. The present embodiment converts the loaded fundamental mode quality factor into an unloaded fundamental mode quality factor for calculation. The unloaded fundamental mode quality factor has higher accuracy than the loaded fundamental mode quality factor.

[0024] The embodiment of the present invention estimates the loss change of the half-wave resonator 10 by measuring the change in the quality factor of the half-wave resonator 10. The loss of the resonator is due to multiple factors, including the resistance of the conductor, material loss, and radiation loss. When an external magnetic field is applied, other losses barely change, so the change in loss of the half-wave resonator 10 is mainly due to the change in the resistance of the magnetoresistive element 12. Because the change in resistance of the magnetoresistive element 12 is due to the applied magnetic field, the change in the resistance of the magnetoresistive element 12 in the magnetic field can be used to determine the loss change of the magnetoresistive element. The change in loss can then be used to determine the change in the quality factor, and a calibration curve between the quality factor and the magnetic field can be established. This allows the magnetic field sensor to estimate the magnitude of the applied magnetic field based on the change in the quality factor, thereby improving the sensitivity and accuracy of the magnetic field sensor.

[0025] The quality factor of a resonator is the ratio of its energy storage capacity to its energy loss rate, and can be expressed as: Q = 2π × stored energy / energy loss rate The stored energy refers to the energy stored when the resonator is in a stable oscillation state, and the energy loss rate represents the rate at which energy is lost in the resonator. The quality factor can be measured using the 3 dB bandwidth method, and the Q factor can be calculated using the following formula: Q = Resonant frequency / 3dB bandwidth A resonator may have multiple resonant modes and corresponding resonant frequencies, and the embodiment of the present invention selects and uses the fundamental mode resonance. The fundamental mode quality factor of the half-wave resonator 10 in the embodiment of the present invention reflects the rate of energy stored and lost by the half-wave resonator 10 at the fundamental mode resonance frequency. As can be seen from FIG. 4, the fundamental mode Q factor decreases as the resistivity of the magnetoresistive element 12 increases. By measuring the quality factor and substituting it into the calibration curve for quality factor and magnetic field, the magnitude of the current magnetic field can be accurately measured.

[0026] A magnetic field sensor according to a technical aspect of an embodiment of the present invention comprises a ground wire 30, a substrate 20, and a half-wavelength resonator 10, which are stacked in sequence along the thickness direction Y of the magnetic field sensor, and the half-wavelength resonator 10 comprises a conductor segment and a magnetoresistive element 12, which is located at the center of the conductor segment, and which comprises a first conductor segment 11 and a second conductor segment 13, both sides of which contact the first conductor segment 11 and the second conductor segment 13, respectively, and the magnetoresistive element 12 is electrically connected to the first conductor segment 11 and the second conductor segment 13, respectively, and the first conductor segment 11, the magnetoresistive element 12, and the second conductor segment 13 are arranged in sequence along the length direction X of the magnetic field sensor. By positioning the magnetoresistive element 12 at the center of the conductor segment, the magnetoresistive element 12 is located at the point of maximum current, making it more sensitive to changes in resistance due to changes in current, thereby more sensitively determining changes in loss of the magnetoresistive element 12 and changes in the quality factor.Furthermore, the strength of the external magnetic field can be obtained based on changes in the quality factor of the magnetic field sensor, thereby improving the sensitivity of the magnetic field sensor.In addition, a calibration curve between the quality factor and the magnetic field can be determined based on the change in resistance of the magnetoresistive element 12 in the magnetic field.By measuring the quality factor and substituting the measured quality factor into the calibration curve between the quality factor and the magnetic field, the magnitude of the current magnetic field can be accurately measured, improving the sensitivity and accuracy of the magnetic field sensor.

[0027] Preferably, Figures 5 and 6 are structural schematic diagrams of another magnetic field sensor according to Example 1 of the present invention, where, refer to Figure 2, the thickness of the magnetoresistive element 12 and the conductor segment are the same, or refer to Figure 5, the thickness of the magnetoresistive element 12 is greater than the thickness of the conductor segment, or refer to Figure 6, the thickness of the magnetoresistive element 12 is less than the thickness of the conductor segment.

[0028] 2, the thickness of the magnetoresistive element 12 and the conductor segments are the same, and the upper surface of the magnetoresistive element 12 facing away from the substrate 20 is flush with the upper surface of the conductor segments facing away from the substrate 20. Referring to FIG. 5, the thickness of the magnetoresistive element 12 is greater than that of the conductor segments, and the upper surface of the magnetoresistive element 12 facing away from the substrate 20 is higher than the upper surface of the conductor segments facing away from the substrate 20. The thickness of the magnetoresistive element 12 is less than that of the conductor segments, and the upper surface of the magnetoresistive element 12 facing away from the substrate 20 is lower than the upper surface of the conductor segments facing away from the substrate 20. The size of the magnetoresistive element 12 controls the magnitude of the magnetic field in the measurable area; the smaller the magnetoresistive element 12, the more accurate the magnetic field that can be measured. The larger the magnetoresistive element 12, the larger the area of the magnetic field that can be measured, and what is measured is the average value in the area.

[0029] Preferably, Figure 7 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention. Referring to Figure 7, the width of the magnetic resistance element 12 is smaller than the width of the conductor segment, wherein the first conductor segment 11 and the second conductor segment 13 both have a first portion 01 and a transient portion 02, the transient portion 02 is located on the side of the first portion 01 closer to the magnetic resistance element 12, and the width of the transient portion 02 gradually changes from the width of the first portion to the width of the magnetic resistance element 12, wherein the width of the magnetic resistance element and the width of the conductor segment are both dimensions along the width direction of the magnetic field sensor, and the width direction of the magnetic field sensor and the length direction of the magnetic field sensor are perpendicular to each other.

[0030] Here, along the width direction Z of the magnetic field sensor, the width of the magnetoresistive element 12 is smaller than the width of the conductor segment, and the transition portion 02 is electrically connected to the magnetoresistive element 12, which enables the width of one end of the conductor segment close to the magnetoresistive element 12 to match the width of the magnetoresistive element 12. The embodiment of the present invention does not specifically limit the structure of the transition portion 12, and the cross-sectional structural schematic diagram along the cutting line BB' in Figure 7 is consistent with the structure in Figure 2. Simply positioning the magnetoresistive element 12 at the midpoint of the conductor segment can improve the measurement sensitivity of the magnetic field sensor, simplify the manufacturing process, avoid mechanical manufacturing defects, and improve device reliability.

[0031] Preferably, FIG. 8 is a structural schematic diagram of another magnetic field sensor according to Example 1 of the present invention, and referring to FIG. 8, the shape of the half-wave resonator 10 is "U" type.

[0032] Here, the half-wave resonator 10 is a U-shaped resonator, and includes a magnetoresistive element 12, a first conductor segment 11, and a second conductor segment 12. The magnetoresistive element 12 is located at the center of the half-wave resonator 10, i.e., the center of the curved portion of the U-shaped resonator, and is electrically connected to the first conductor segment 11 and the second conductor segment 12. The magnetoresistive element 12 is located on one side of the magnetic field sensor, making measurement simpler and easier.

[0033] Preferably, Figures 9 to 11 are structural schematic diagrams of another magnetic field sensor according to Example 1 of the present invention, and referring to Figures 9 to 11, the magnetic field sensor further includes a protective layer 40 located on the side of the magnetoresistive element 12 farther from the substrate 10 and covering the magnetoresistive element 12.

[0034] Here, the protective layer 40 is made of a low dielectric constant material, including, but not limited to, fluorine-doped silica, organic silicone glass, porous silica, or a combination thereof. By using a low dielectric constant material, the influence on the line of the magnetic field sensor can be reduced, and the protective layer 40 can protect the magnetoresistive element 102 from destruction. The length and width of the protective layer 40 may be greater than the length and width of the magnetoresistive element 12, respectively, or may be equal to the length and width of the magnetoresistive element 12, respectively, or the sum of the thicknesses of the protective layer 40 and the magnetoresistive element 12 may be equal to the thickness of the conductor segment. As long as it is ensured that the protective layer 40 can cover the magnetoresistive element 102, the structure and dimensions of the protective layer are not specifically limited.

[0035] Preferably, the magnetoresistive element is a metal magnetoresistive element, and the metal magnetoresistive element includes one of a giant magnetoresistive element, a tunneling magnetoresistive element, and an anisotropic magnetoresistive element.

[0036] Here, magnetoresistance refers to the change in resistivity of a sample in an external magnetic field of strength H, TIFF2025117509000002.tif12129 where δH represents the magnetoresistance, R(H) is the resistivity of the sample in a magnetic field of strength H, and R(0) is the resistivity of the sample when H=0.

[0037] The magnetoresistive element in an embodiment of the present invention is a metal magnetoresistive element. The metal magnetoresistive element may be a giant magnetoresistive (GMR) element, a tunneling magnetoresistive (TMR) element, or an anisotropic magnetoresistive (AMR) element. Typically, the δH values of GMR elements, TMR elements, and AMR elements are larger than the δH values of semiconductor magnetoresistive elements. Taking GMR as an example, GMR is a spin-electron effect, and the operation of a GMR element is based on the dependence of electron scattering on the spin orientation. The thin-film structure of a GMR element is composed of alternating ferromagnetic and non-ferroconductive layers. Depending on the magnetization arrangement of adjacent ferromagnetic layers, the total resistivity of the thin-film structure can change significantly. When aligned parallel, the total resistivity is relatively low, and when aligned antiparallel, the total resistivity is relatively high. The change in resistance of the metal magnetoresistive element is obvious, and the metal magnetoresistive element has higher sensitivity, responsivity, and reliability than other types of magnetoresistive elements.

[0038] Preferably, the half-wave resonator is a planar transmission line, which includes one of a stripline, a microstripline, and a coplanar line.

[0039] Here, the fabrication of striplines, microstriplines and coplanar lines is simple and easy to operate.

[0040] Example 2 Based on the above embodiments, an embodiment of the present invention provides a measurement method for a magnetic field sensor, and employs a magnetic field sensor according to any embodiment of the present invention. Figure 12 is a flowchart of the measurement method for a magnetic field sensor according to embodiment 2 of the present invention. Refer to Figure 12, the measurement method includes:

[0041] In S110, a calibration curve between the quality factor of the magnetic field sensor and the magnetic field strength is obtained.

[0042] Here, the change in the resistance of the magnetoresistive element in the magnetic field can be used to determine the change in loss of the magnetoresistive element, and the change in loss can be used to determine the change in quality factor, and a calibration curve between the quality factor and the magnetic field can be determined.

[0043] At S120, a quality factor measurement of the magnetic field sensor is obtained.

[0044] Here, the resonant frequency and bandwidth of the magnetic field sensor are determined by coupling between at least one coupling unit, whose transmission impedance is the same as the characteristic impedance of the external measurement line, and the half-wave resonator, and the quality factor measurement value of the magnetic field sensor is determined based on the resonant frequency and bandwidth of the magnetic field sensor.

[0045] In S130, the to-be-measured magnetic field strength of the magnetic field sensor is determined based on the calibration curve and the quality factor measurement value.

[0046] Here, by substituting the quality factor measurement value into the calibration curve, the magnetic field intensity to be measured of the magnetic field sensor corresponding to the quality factor measurement value can be obtained.

[0047] The measurement method of the magnetic field sensor according to the embodiment of the present invention can accurately measure the magnitude of the current magnetic field by substituting the measured quality factor into a calibration curve of the quality factor and the magnetic field, thereby improving the sensitivity and accuracy of the magnetic field sensor.

[0048] Preferably, obtaining a quality factor measurement of the magnetic field sensor comprises: The method includes determining a resonant frequency and bandwidth of the magnetic field sensor by coupling between at least one coupling unit, the transmission impedance of which is the same as the characteristic impedance of the external measurement line, and the half-wavelength resonator, and determining a quality factor measurement value of the magnetic field sensor based on the resonant frequency and bandwidth of the magnetic field sensor.

[0049] Here, the coupling unit may be one or two. FIG. 13 is a structural schematic diagram of a magnetic field sensor with a coupling unit according to a second embodiment of the present invention. Referring to FIG. 13, the coupling unit includes a first coupling unit 51 and a second coupling unit 52. The coupling method in FIG. 13 is parallel coupling. The coupling between the coupling unit and the half-wave resonator may include end-to-end coupling or electrical connection coupling. The coupling unit determines the resonant frequency and bandwidth of the magnetic field sensor. The coupling unit may be made of a transmission line, whose characteristic impedance matches the characteristic impedance of the external measurement line, e.g., 50 Ω, thereby reducing the influence of reflected electromagnetic waves and improving measurement accuracy. The coupling unit and the half-wave resonator may be made of the same type of transmission line or different types of transmission lines. The coupling unit and the half-wave resonator may be made of the same material or different materials. The substrate, conductor segments, coupling unit, and ground line may all be made of non-magnetic materials. The Q factor is the unloaded fundamental mode Q factor, making the measurement more accurate.

[0050] It should be understood that the various types of flows shown above can be used, and steps can be rearranged, added, or deleted. For example, the steps described in the present invention can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical aspects of the present invention are achieved, and this specification is not limited thereto.

[0051] The above specific embodiments do not limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions are possible based on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A magnetic field sensor, a ground line, a substrate, and a half-wave resonator that are sequentially stacked along the thickness direction of the magnetic field sensor; The half-wave resonator comprises a conductor segment having a first conductor segment and a second conductor segment, and a magnetoresistive element located at a center position of the conductor segment, both sides of the magnetoresistive element contacting the first conductor segment and the second conductor segment, respectively, and electrically connected to the first conductor segment and the second conductor segment, respectively, and the first conductor segment, the magnetoresistive element, and the second conductor segment are sequentially arranged along the longitudinal direction of the magnetic field sensor. A magnetic field sensor characterized by:

2. The thickness of the magnetoresistive element and the thickness of the conductor segment are the same, or the thickness of the magnetoresistive element is greater than the thickness of the conductor segment, or the thickness of the magnetoresistive element is less than the thickness of the conductor segment.

2. The magnetic field sensor according to claim 1.

3. The width of the magnetic resistance element is smaller than the width of the conductor segment, and each of the first conductor segment and the second conductor segment comprises a first portion and a transition portion located on a side of the first portion closer to the magnetic resistance element, the transition portion having a width that gradually changes from the width of the first portion to the width of the magnetic resistance element, and the width of the magnetic resistance element and the width of the conductor segment are both dimensions along the width direction of the magnetic field sensor, and the width direction of the magnetic field sensor and the length direction of the magnetic field sensor are perpendicular to each other.

2. The magnetic field sensor according to claim 1.

4. The shape of the half-wave resonator is "U"-shaped.

2. The magnetic field sensor according to claim 1.

5. a protective layer positioned on a side of the magnetoresistive element farther from the substrate and covering the magnetoresistive element; 2. The magnetic field sensor according to claim 1.

6. the magnetoresistive element is a metal magnetoresistive element, the metal magnetoresistive element includes one of a giant magnetoresistive element, a tunnel magnetoresistive element, and an anisotropic magnetoresistive element; 6. The magnetic field sensor according to claim 1 or 5.

7. the half-wave resonator is a planar transmission line; The planar transmission line includes one of a stripline, a microstripline, and a coplanar line.

2. The magnetic field sensor according to claim 1.

8. The magnetic field sensor according to claim 1 is employed, Obtaining a calibration curve between the quality factor of the magnetic field sensor and the magnetic field strength; Obtaining a quality factor measurement of a magnetic field sensor; determining a to-be-measured magnetic field strength of the magnetic field sensor based on the calibration curve and the quality factor measurement value; A magnetic field sensor measurement method comprising:

9. Obtaining a quality factor measurement of a magnetic field sensor includes: determining a resonant frequency and a bandwidth of the magnetic field sensor by coupling between at least one coupling unit, the transmission impedance of which is the same as the characteristic impedance of the external measurement line, and the half-wave resonator; determining a quality factor measurement of the magnetic field sensor based on a resonant frequency and a bandwidth of the magnetic field sensor; 9. The method for measuring a magnetic field sensor according to claim 8.

10. The coupling between the coupling unit and the half-wave resonator includes one of parallel coupling, end-to-end coupling and electrical connection coupling.

10. The method for measuring a magnetic field sensor according to claim 9.

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