Spin-orbit-torque based magnetic sensor and magnetic field measurement method usig the magnetic sensor

Abstract

The present invention comprises a substrate, an electrode layer formed on the substrate, and a pair of sensing elements stacked on the substrate and connected to the electrode layer, wherein the direction of the current applied through the electrode layer and flowing to the pair of sensing elements is opposite to each other. According to the present invention, effective magnetic field measurement is possible without the addition of additional circuits, an increase in area, or power consumption.

Description

Technology Field

[0001] The present invention relates to a magnetic sensor based on spin-orbit torque properties and a method for measuring a magnetic field using the same. Background Technology

[0002] A magnetic sensor is a device that detects changes in an applied magnetic field and converts them into electrical signals. Currently, the Hall sensor is a widely used commercial magnetic sensor. The Hall sensor is a device that converts changes in a magnetic field passing through a cross-shaped metal layer into a voltage difference, and it is recently being used for the image stabilization function in smartphone cameras.

[0003] In addition to Hall sensors, magneto-resistance sensors, which utilize magnetoresistance, are another type of sensor capable of measuring magnetic fields. Sensors utilizing the magnetoresistance effect take advantage of the phenomenon where the electrical resistance of the material constituting the sensor changes depending on the presence or absence of a magnetic field. Magneto-resistance sensors utilize anisotropic magneto-resistance (AMR), giant magneto-resistance (GMR), or tunneling magneto-resistance (TMR). Regardless of the operating principle used, magneto-resistance sensors have the advantage of being at least 10 times more sensitive than conventional Hall sensors.

[0004] Anisotropic magnetoresistance is an effect observed in ferromagnetic metals and their alloys, known as an additional effect beyond normal magnetoresistance. Attributable to spin-orbit interaction, it occurs depending on the magnetization biaxiality of the ferromagnetic material and the angle between the external magnetic field and the current, and is known to have relatively low sensitivity.

[0005] The giant magnetoresistance phenomenon is a phenomenon in which electrical resistance differs significantly when the magnetic directions of two magnetic layers are parallel and antiparallel. This is realized through a multilayer structure in which a conductive film is formed between two magnetic thin films. Among the two magnetic thin films, a layer with a fixed magnetization direction is provided, and maximum resistance appears when the magnetization direction of the magnetic thin films is reversed.

[0006] Conventional SOT-based magnetic sensors like the one in Fig. 1 are basically composed of a single sensing layer in a crossbar array structure.

[0007] When a current is applied through the electrode in the same direction as the magnetic field while a magnetic field is applied in a specific direction, the Hall voltage V at the sensing layer H Measure the (+) and, with the directions of the magnetic field or current set opposite to each other, the Hall voltage V H By measuring the negative value, the difference between the two Hall voltages, i.e., ΔV=V +H -V -H It is designed to be used as a magnetic sensor by calculating.

[0008] The disadvantage of this structure is that because it uses a single sensing layer, V H (+), V H The point is that measuring (-) individually complicates the circuit design.

[0009] When fabricating a sensor using a single component, measurements must be taken in both DC and AC ways to utilize it as a sensor. When using AC, there is a disadvantage in that additional components are required in the circuit because the voltage must be measured using a Rock-in amplifier. Furthermore, when using DC, as shown in the diagram, two sets of data—one for the current flowing to the right and the other for the current flowing to the left—are required to achieve the range and sensitivity of the magnetic field sensor currently in use. In this case, there is a problem inevitably that power consumption increases because the current must be sent twice.

[0010] In the current method, the values ​​of the current flowing to the right and the current flowing to the left must be added together; however, to utilize the calculated value, a logic circuit is required to calculate the two voltage values ​​using an additional circuit later on.

[0011] Ultimately, since both AC and DC methods require additional circuitry, there is a problem in that the area increases during device packaging.

[0012] The matters described in the background technology above are intended to aid in understanding the background of the invention and may include matters that are not prior art already known to those skilled in the art to which this technology belongs. Prior art literature

[0013] Korean Patent Publication No. 10-2020-0065678 The problem to be solved

[0014] The present invention has been devised to solve the aforementioned problems, and the purpose of the present invention is to provide a spin orbit torque-based magnetic sensor capable of effectively measuring a magnetic field without the addition of additional circuits, an increase in area, or power consumption, and a method for measuring a magnetic field using said magnetic sensor. means of solving the problem

[0015] A spin orbit torque-based magnetic sensor according to one aspect of the present invention comprises a substrate, an electrode layer formed on the substrate, and a pair of sensing elements stacked on the substrate and connected to the electrode layer, wherein the direction of the current applied through the electrode layer and flowing to the pair of sensing elements is opposite to each other.

[0016] Here, the direction of the current flowing in the first element among the pair of sensing elements is opposite to the direction of the applied magnetic field, and the direction of the current flowing in the second element among the pair of sensing elements is the same as the direction of the applied magnetic field.

[0017] And, the electrode layer comprises a first electrode portion connected to a current source, a pair of second electrode portions branching from the first electrode portion in opposite directions and each connected to one end of the first element and the second element, a pair of third electrode portions on the first element side connected to both ends of the first element and extending in a direction perpendicular to the second electrode portions, and a pair of third electrode portions on the second element side connected to both ends of the second element and extending in a direction perpendicular to the second electrode portions.

[0018] Additionally, the electrode layer may further include a pair of fourth electrode portions, each connected to the other end of the first element and the second element and connected to ground.

[0019] Here, each of the first element and the second element is characterized by having a heavy metal layer, a ferromagnet metal layer, an oxide layer, and a capping layer sequentially stacked.

[0020] In addition, the current applied through the first electrode is branched into a second electrode connected to the first element and a second electrode connected to the second element, so that currents flow in opposite directions through the first element and the second element.

[0021] In particular, it is characterized by being able to simultaneously measure the voltage between the ends of a pair of third electrode portions on the first element side and the voltage between the ends of a pair of third electrode portions on the first element side.

[0022] Meanwhile, the pair of second electrode portions are each characterized by being in contact with one end of the first element and the second element.

[0023] In addition, the pair of second electrode portions are each characterized by being in contact with the ferromagnet metal constituting the first element and the second element.

[0024] In addition, a pair of third electrode portions on the first element side are in contact with both side ends of the first element, and a pair of third electrode portions on the second element side are in contact with both side ends of the second element.

[0025] Next, according to another aspect of the present invention, a spin orbit torque-based magnetic sensor comprises a substrate, an electrode layer formed on the substrate, and a pair of sensing elements stacked on the electrode layer, wherein the direction of the current applied through the electrode layer and flowing through the pair of sensing elements is opposite to each other.

[0026] In addition, the direction of the current flowing in the first element of the pair of sensing elements is opposite to the direction of the applied magnetic field, and the direction of the current flowing in the second element of the pair of sensing elements is the same as the direction of the applied magnetic field.

[0027] Here, the electrode layer comprises a first electrode portion connected to a current source, a pair of second electrode portions branching in opposite directions from the first electrode portion, a pair of third electrode portions on the first element side extending in both directions perpendicularly from the second electrode portion on the first element side among the pair of second electrode portions, and a pair of third electrode portions on the second element side extending in both directions perpendicularly from the second electrode portion on the second element side among the pair of second electrode portions.

[0028] In addition, each of the first element and the second element is characterized by having a heavy metal layer, a ferromagnet metal layer, an oxide layer, and a capping layer sequentially stacked.

[0029] In addition, it is characterized by being able to simultaneously measure the voltage between the ends of a pair of third electrodes on the first element side and the voltage between the ends of a pair of third electrodes on the second element side.

[0030] Here, the first element is characterized by being stacked on an area where the second electrode portion on the first element side and a pair of third electrode portions on the first element side intersect, and the second element is characterized by being stacked on an area where the second electrode portion on the second element side and a pair of third electrode portions on the second element side intersect.

[0031] Next, a magnetic field measurement method using a spin orbit torque-based magnetic sensor according to one aspect of the present invention comprises the steps of: measuring the voltage between the ends of a pair of third electrodes on the first element side and the voltage between the ends of a pair of third electrodes on the second element side when a magnetic field is applied in a direction parallel to the second electrode of the spin orbit torque-based magnetic sensor; and calculating the difference between the voltage between the ends of a pair of third electrodes on the first element side and the voltage between the ends of a pair of third electrodes on the second element side. Effects of the invention

[0032] According to the magnetic sensor of the present invention, there is an advantage in that it provides information necessary for existing sensors with a single application of current, and at the same time performs calculations through an analog circuit.

[0033] Nevertheless, achieving this efficiency does not require increased power consumption, additional circuit configuration, or an increase in area. Brief explanation of the drawing

[0034] Figure 1 illustrates an example of a conventional magnetic sensor. FIG. 2 schematically illustrates the magnetic sensor of the present invention, FIG. 3 shows the circuit configuration of the magnetic sensor of the present invention, and FIG. 4 shows the measured Hall voltage. FIG. 5 shows the planar shape of a magnetic sensor according to the first embodiment of the present invention, and FIG. 6 shows the XX cross-sectional shape of FIG. 5. FIG. 7 shows the planar shape of a magnetic sensor according to a second embodiment of the present invention, and FIG. 8 shows the YY cross-sectional shape of FIG. 7. Specific details for implementing the invention

[0035] In order to fully understand the present invention, the operational advantages of the present invention, and the objectives achieved by the implementation of the present invention, reference must be made to the accompanying drawings illustrating preferred embodiments of the present invention and the contents described therein.

[0036] In describing preferred embodiments of the present invention, known technologies or repetitive descriptions that may unnecessarily obscure the essence of the invention will be shortened or omitted.

[0037] FIG. 2 schematically illustrates the magnetic sensor of the present invention, FIG. 3 shows the circuit configuration of the magnetic sensor of the present invention, and FIG. 4 shows the measured Hall voltage.

[0038] Hereinafter, with reference to FIGS. 2 to 4, a spin orbit torque-based magnetic sensor according to the present invention and a magnetic field measurement method using the magnetic sensor will be described.

[0039] The present invention is a magnetic sensor in which an electrode layer is formed on a substrate (110), and a sensing element is provided on or between the electrode layers, and a magnetic field is sensed by measuring a voltage difference caused by a current flowing through the element when a magnetic field is applied, and a sensing element based on spin-orbit-torque properties is used.

[0040] Unlike conventional magnetic sensors having the same role as the present invention, which measure voltage by applying current in one direction to a single sensing element and measure voltage by applying current in the opposite direction to calculate the difference between the two voltages, the present invention is implemented by providing a pair of sensing elements, a first element (130) and a second element (140), and by applying current in opposite directions to the pair of sensing elements, so that the Hall voltage from both sensing elements can be measured by applying current once and the difference can be calculated at once.

[0041] That is, as referenced in FIGS. 2 to 5, the change is applied by measuring by combining the Hall voltages of two cross-shaped elements using two cross-shaped elements instead of a single cross-shaped element. To solve the problem of having to apply current twice to make it flow in different directions when measuring with DC (Direct Current), cross structures are placed on both sides of the current point to allow the current to flow in different directions at once. Furthermore, the two Hall voltages are connected to be measured simultaneously, thereby allowing the circuit that previously had to be calculated to be supplemented using an analog method.

[0042] FIG. 5 shows a planar shape of a magnetic sensor according to a first embodiment of the present invention, and FIG. 6 shows a cross-sectional shape of FIG. 5. Referring to FIG. 2 and FIG. 5 to FIG. 6, the magnetic sensor according to the first embodiment of the present invention includes a substrate (110), an electrode layer, a first element (130), and a second element (140).

[0043] The electrode layer includes a first electrode portion (121), a pair of second electrode portions (122-1, 122-2), a pair of third electrode portions (123-1, 123-2), and a pair of fourth electrode portions (124-1, 124-2).

[0044] The first electrode (121) is connected to a current source.

[0045] A pair of second electrode sections (122-1, 122-2) branch off from the first electrode section (121) in opposite directions and are preferably parallel to the direction of the magnetic field (B field).

[0046] A pair of second electrode sections (122-1, 122-2) are branched from the first electrode section (121) and connected to one end of the first element (130) and the second element (140), respectively.

[0047] In addition, a pair of fourth electrode parts (124-1, 124-2) are provided, each connected to the other end of the first element (130) and the second element (140) and connected to ground, and it is preferable that the fourth electrode parts (124-1, 124-2) are also in a direction parallel to the direction of the magnetic field (B field).

[0048] Additionally, a pair of third electrode sections (123-1) on the first element side are formed, which are connected to both ends of the first element (130) and extend in a direction perpendicular to the second electrode section (122-1) and the fourth electrode section (124-1). This direction is also perpendicular to the direction of the magnetic field (B field).

[0049] Likewise, a pair of second element-side third electrode portions (123-2) are formed, which are connected to each of the two side ends of the second element (140) and extend in a direction perpendicular to the second electrode portion (122-2) and the fourth electrode portion (124-2). This is also a direction perpendicular to the direction of the magnetic field (B field).

[0050] Next, each of the first element (130) and the second element (140) has a cell structure in which a heavy metal layer (131, 141, Heavy metal), a ferromagnet layer (132, 142, Ferromagnet metal), an oxide layer (133, 143, Oxide), and a capping layer (134, 144, Capping layer) are sequentially stacked, thereby exhibiting spin-orbit-torque properties.

[0051] The magnetic sensor of the present invention has the above configuration, so that the current applied from the current source through the first electrode part (121) is branched through a pair of second electrode parts (122-1, 122-2) and flows to the first element (130) and the second element (140), respectively.

[0052] In the example of the city, the current flowing through the first element (130) is in the opposite direction to the magnetic field, and the current flowing through the second element (140) is in the direction parallel to the magnetic field.

[0053] In this manner, when a unidirectional magnetic field is applied, current flows through the first element (130) and the second element (140), a Hall voltage is generated, and the voltage (V) between the two ends of a pair of third electrode portions (123-1) on the first element side connected to the first element (130) +H ) and the voltage (V) between the two ends of a pair of third electrode parts (123-2) connected to the second element (140) -H Can measure ) and V +H and V -H Changes in the magnitude and direction of the magnetic field are detected by measuring the difference (ΔV) by applying a current once.

[0054] The basic structure of this first embodiment can be fabricated by placing the electrode inside the magnetic domain, as one of the proposed methods to minimize the effect of the magnetic domain. The advantage of this structure is that the entire operating area of ​​the device is a magnetic domain, allowing the sensitivity of the Hall sensor to be controlled by the magnetic domain.

[0055] The difference from other structures lies in the process of fabricating the structure. A thin film structure of a device consisting of a heavy metal / ferro magnet metal / oxide / capping layer is etched by stacking a mask in the shape of a dotted line and ion-milling. Subsequently, a structure as shown in FIGS. 8 and 9 is fabricated by stacking the part corresponding to the electrode layer.

[0056] This structure has the advantage that magnetic domains can be stably formed because a ferromagnetic material exists entirely between the electrodes through which current flows, and the large surface area makes it easy to generate and manipulate, thus making it useful for use in sensors.

[0057] Next, FIG. 7 shows a planar shape of a magnetic sensor according to a second embodiment of the present invention, and FIG. 8 shows a YY cross-sectional shape of FIG. 7. Referring to FIG. 2 and FIG. 7 to FIG. 8, the magnetic sensor according to the second embodiment of the present invention includes a substrate (110), an electrode layer, a first element (130), and a second element (140). Description of configurations identical to those in the preceding embodiment will be omitted.

[0058] The electrode layer includes a first electrode portion (121), a pair of second electrode portions (222-1, 222-2), and a pair of third electrode portions (223-1, 223-2).

[0059] The first electrode (121) is connected to a current source.

[0060] A pair of second electrode sections (222-1, 222-2) branch off from the first electrode section (121) in opposite directions and are preferably parallel to the direction of the magnetic field (B field).

[0061] Unlike the first embodiment, a pair of second electrode parts (222-1, 222-2) branch off from the first electrode part (121), and both ends are connected to ground.

[0062] And, a pair of third electrode sections (223-1) on the first element side are formed, extending in both directions perpendicular to the second electrode section (222-1) from the second electrode section (222-1) on the first element side (130). This is also a direction perpendicular to the direction of the magnetic field (B field).

[0063] Additionally, a pair of third electrode portions (223-2) on the second element side are formed, extending in both directions perpendicular to the second electrode portion (222-2) from the second electrode portion (222-2) on the second element side (140). This direction is also perpendicular to the direction of the magnetic field (B field).

[0064] Unlike the first embodiment, the first element (130) and the second element (140) are each formed by stacking on the area where the second electrode portion (222-1) and the third electrode portion (223-1) on the first element side and the second electrode portion (222-2) and the third electrode portion (223-2) on the second element side intersect.

[0065] Each of the first element (130) and the second element (140) has a cell structure in which a heavy metal layer (131, 141, Heavy metal), a ferromagnet layer (132, 142, Ferromagnet metal), an oxide layer (133, 143, Oxide), and a capping layer (134, 144, Capping layer) are sequentially stacked, thereby exhibiting spin-orbit-torque properties.

[0066] In the magnetic sensor according to the second embodiment, the current applied from the current source through the first electrode part (121) is branched through a pair of second electrode parts (222-1, 222-2) and flows to the first element (130) and the second element (140), respectively.

[0067] In the example of the city, the current flowing through the first element (130) is in the opposite direction to the magnetic field, and the current flowing through the second element (140) is in the direction parallel to the magnetic field.

[0068] In this manner, when a unidirectional magnetic field is applied, current flows through the first element (130) and the second element (140), a Hall voltage is generated, and the voltage (V) between the two ends of a pair of third electrode portions (223-1) on the first element side connected to the first element (130) +H ) and the voltage between the two ends of a pair of third electrode parts (223-2) connected to the second element (140) (V -H Can measure ) and V +H and V -H Changes in the magnitude and direction of the magnetic field are detected by measuring the difference (ΔV) by applying a current once.

[0069] The structure of the second embodiment is a structure in which a ferromagnetic layer is stacked on top of an electrode, thereby reducing the influence of the domain by making the magnetic domain region smaller. In the structure, it is more desirable for the device characteristics of the first device and the second device to be the same, as this is more efficient in reducing the effect of the magnetic domain region.

[0070] Since the process of the structure can be simplified by first stacking the electrodes and then stacking a circular ferromagnetic layer on top, the process steps can be simplified compared to the first embodiment.

[0071] Since the magnetic domain is small, the amount of power consumed to operate the device is reduced, and as mentioned earlier, effects caused by ferromagnets, such as Dzyaloshinskii-Moriya interaction other than the effect of spin orbit torque, can be reduced, which can help improve the accuracy of the sensor.

[0072] The magnetic sensor of the present invention as described above is expected to be utilized in various ways.

[0073] This technology belongs to the field of magnetic sensors and is expected to be applicable to various application fields such as conventional Hall sensors, magnetoresistance sensors, magnetic sensors, semiconductor devices, high-end industrial sensor applications, biomedical sensor applications, precision magnetic field measurement, ultra-precision speed and coordinate sensing, geomagnetic sensing, metal object detection, non-destructive testing (NDT), magnetic communication, and 3D magnetic imaging.

[0074] Furthermore, it can be applied as a shunt resistance current sensor used in electric vehicles for autonomous driving. In other words, compared to Hall-current sensors with large error and noise voltages, the shunt resistance current sensor with this device structure can achieve low noise.

[0075] In addition, it can be utilized as a core sensor that implements various functions by detecting location, direction, movement, and posture, applied to smartphones, game consoles, navigation systems, IoT, etc., as well as as a user interface and motion recognition component for pedestrian and vehicle navigation, black boxes, game consoles, smartphones, etc., and as an inertial and magnetic sensor, which is a core technology for camera image stabilization, remote controls, flip covers, OIS, Auto-Focus, Pan / Tilt, geomagnetic sensors, and 9-axis smart motion sensors.

[0076] Although the present invention has been described above with reference to the illustrated drawings, it is obvious to those skilled in the art that it is not limited to the described embodiments and can be modified and varied in various ways without departing from the spirit and scope of the invention. Accordingly, such modifications or variations should be deemed to fall within the scope of the claims of the present invention, and the scope of rights of the present invention should be interpreted based on the appended claims. Explanation of the symbols

[0077] 110 : Substrate 121 : First electrode part 122-1, 122-2, 222-1, 222-2: Second electrode part 123-1, 223-1: Third electrode part on the first element side 123-2, 223-2: Third electrode part on the second element side 124-1, 124-2: 4th electrode part 130: 1st element 140: 2nd element 131, 141: Heavy metal layer 132, 142: Ferromagnetic layer 133, 143: Oxide layer 134, 144: Cover layer

Claims

Claim 1 A spin orbit torque-based magnetic sensor comprising: a substrate; an electrode layer formed on the substrate; and a pair of sensing elements stacked on the substrate and connected to the electrode layer, wherein the direction of the current applied through the electrode layer and flowing to the pair of sensing elements is opposite to each other, and wherein the electrode layer comprises: a first electrode portion connected to a current source; a pair of second electrode portions branching from the first electrode portion in opposite directions and connected to one end of the first element and the second element, respectively; a pair of first element-side third electrode portions each connected to both end of the first element and each extending in a direction perpendicular to the second electrode portions and formed symmetrically to each other; and a pair of second element-side third electrode portions each connected to both end of the second element and each extending in a direction perpendicular to the second electrode portions and formed symmetrically to each other. Claim 2 A spin orbit torque-based magnetic sensor according to claim 1, characterized in that the direction of the current flowing in the first element among the pair of sensing elements is opposite to the direction of the applied magnetic field, and the direction of the current flowing in the second element among the pair of sensing elements is the same as the direction of the applied magnetic field. Claim 3 delete Claim 4 A spin orbit torque-based magnetic sensor according to claim 1, wherein the electrode layer further comprises a pair of fourth electrode portions connected to ground and each connected to the other end of the first element and the second element. Claim 5 A spin orbit torque-based magnetic sensor according to claim 1, wherein each of the first element and the second element is characterized by having a heavy metal layer, a ferromagnet metal layer, an oxide layer, and a capping layer sequentially stacked. Claim 6 A spin orbit torque-based magnetic sensor according to claim 1, wherein the current applied through the first electrode portion is branched into a second electrode portion connected to the first element and a second electrode portion connected to the second element, such that currents flow in opposite directions through the first element and the second element. Claim 7 A spin orbit torque-based magnetic sensor according to claim 1, characterized in that it is capable of simultaneously measuring the voltage between the ends of a pair of third electrode portions on the first element side and the voltage between the ends of a pair of third electrode portions on the second element side. Claim 8 A spin orbit torque-based magnetic sensor according to claim 1, wherein a pair of second electrode portions each contact one end of the first element and the second element. Claim 9 A spin orbit torque-based magnetic sensor according to claim 8, wherein a pair of second electrode portions each contact a ferromagnet metal constituting the first element and the second element. Claim 10 A spin orbit torque-based magnetic sensor according to claim 8, characterized in that a pair of third electrode portions on the first element side contact both side ends of the first element, and a pair of third electrode portions on the second element side contact both side ends of the second element. Claim 11 A spin orbit torque-based magnetic sensor comprising: a substrate; an electrode layer formed on the substrate; and a pair of sensing elements stacked on the electrode layer, wherein the direction of the current applied through the electrode layer and flowing to the pair of sensing elements is opposite to each other, and wherein the electrode layer comprises: a first electrode portion connected to a current source; a pair of second electrode portions branching from the first electrode portion in opposite directions and each connected to one end of the first element and the second element, respectively; a pair of first element-side third electrode portions each connected to both end of the first element and each extended in a direction perpendicular to the second electrode portions and formed symmetrically to each other; and a pair of second element-side third electrode portions each connected to both end of the second element and each extended in a direction perpendicular to the second electrode portions and formed symmetrically to each other. Claim 12 A spin orbit torque-based magnetic sensor according to claim 11, characterized in that the direction of the current flowing in the first element among the pair of sensing elements is opposite to the direction of the applied magnetic field, and the direction of the current flowing in the second element among the pair of sensing elements is the same as the direction of the applied magnetic field. Claim 13 delete Claim 14 A spin orbit torque-based magnetic sensor according to claim 11, wherein each of the first element and the second element is characterized by having a heavy metal layer, a ferromagnet metal layer, an oxide layer, and a capping layer sequentially stacked. Claim 15 A spin orbit torque-based magnetic sensor according to claim 11, characterized in that it is possible to simultaneously measure the voltage between the ends of a pair of third electrode portions on the first element side and the voltage between the ends of a pair of third electrode portions on the second element side. Claim 16 A spin orbit torque-based magnetic sensor according to claim 11, wherein the first element is stacked on an area where the second electrode portion on the first element side and a pair of third electrode portions on the first element side intersect, and the second element is stacked on an area where the second electrode portion on the second element side and a pair of third electrode portions on the second element side intersect. Claim 17 A method for measuring a magnetic field using a spin orbit torque-based magnetic sensor, comprising: a step of measuring the voltage between the ends of a pair of third electrodes on the first element side and the voltage between the ends of a pair of third electrodes on the second element side when a magnetic field is applied in one direction parallel to the second electrode of the spin orbit torque-based magnetic sensor of claim 1 or claim 11; and a step of calculating the difference between the voltage between the ends of a pair of third electrodes on the first element side and the voltage between the ends of a pair of third electrodes on the first element side.

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