JP2017146311A - Magnetic field generator and magnetic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a magnetic field generator in which a plurality of magnetic field generating units is arrayed in a desired pattern and which is highly resistant to a disturbance magnetic field.SOLUTION: A magnetic field generator 100 is equipped with a plurality of magnetic field generating units 200 which is arranged in a prescribed pattern and which generates a plurality of external magnetic fields. Each of the plurality of magnetic field generating units 200 includes a first ferromagnetic body and a first anti-ferromagnetic body. Each first anti-ferromagnetic body is in contact with the first ferromagnetic body and exchange-coupled with the first ferromagnetic body. The first ferromagnetic body has magnetization. Each of the plurality of magnetic field generating units 100 contains two magnetic field generating units 200 differing from each other in a direction of the magnetization of the first ferromagnetic bodies.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a magnetic field generator including a plurality of magnetic field generators, and a magnetic sensor system and a magnetic sensor including the magnetic field generator.

  2. Description of the Related Art In recent years, magnetic sensor systems that detect physical quantities related to rotational motion and linear motion of an operating body have been used in various applications. Patent Document 1 describes a magnetic sensor system that includes a scale and a magnetic sensor, and is configured to generate a signal related to the relative positional relationship between the scale and the magnetic sensor.

  The magnetic sensor includes a magnetic detection element that detects a magnetic field to be detected. Patent Document 1 describes a magnetic sensor using a so-called spin-valve magnetoresistive element (hereinafter also referred to as an MR element) as a magnetic detection element. A spin-valve MR element includes a magnetization fixed layer having a magnetization whose direction is fixed, a free layer whose magnetization changes according to a magnetic field to be detected, and a nonmagnetic layer disposed between the magnetization fixed layer and the free layer. And have a layer. The spin valve MR element includes a TMR element in which the nonmagnetic layer is a tunnel barrier layer and a GMR element in which the nonmagnetic layer is a nonmagnetic conductive layer.

  The scale of the magnetic sensor system has a plurality of magnetic field generation units that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. In general, each of the plurality of magnetic field generating units is constituted by a permanent magnet. The magnetization directions of the plurality of magnetic field generators are set so as to be switched alternately. As a result, the directions of the external magnetic fields generated by the plurality of magnetic field generating units are alternately switched.

  Some magnetic sensors include means for applying a bias magnetic field to the magnetic detection element. The bias magnetic field is used, for example, so that the magnetic detection element responds linearly to changes in the strength of the magnetic field to be detected. In a magnetic sensor using a spin-valve MR element, the bias magnetic field is used to make the free layer a single domain and to direct the magnetization of the free layer in a certain direction when there is no magnetic field to be detected. Also used for.

  Patent Document 1 describes a magnetic sensor including a bias magnetic field generator that generates a plurality of bias magnetic fields applied to a plurality of MR elements. The bias magnetic field generator includes a plurality of pairs of magnetic field generators provided corresponding to the plurality of MR elements. The pair of magnetic field generators are arranged such that corresponding MR elements are interposed between them. Each magnetic field generator is composed of a permanent magnet and generates an external magnetic field.

  Hereinafter, a structure including a plurality of magnetic field generators that generate a plurality of external magnetic fields arranged in a predetermined pattern like a scale is referred to as a magnetic field generator. In a magnetic sensor including a bias magnetic field generator, a plurality of magnetic field generators constituting the bias magnetic field generator are arranged in a predetermined pattern. Therefore, this bias magnetic field generator can also be said to be a magnetic field generator.

JP 2014-209089 A

  In the magnetic sensor system and the magnetic sensor including the magnetic field generator including a plurality of magnetic field generators each formed of a permanent magnet, the following problems have occurred. Such a magnetic sensor system and a magnetic sensor are usually used under the condition that the strength of the magnetic field to be detected does not exceed the coercive force of the permanent magnet. However, since the magnetic sensor system and the magnetic sensor can be used in various environments, a disturbance magnetic field having a strength exceeding the coercive force of the permanent magnet may be temporarily applied to the permanent magnet. When such a disturbance magnetic field is temporarily applied to the permanent magnet, the magnetization direction of the permanent magnet may change from the original direction, and may remain changed from the original direction even if the disturbance magnetic field disappears. . In this case, the direction of the magnetic field generated by each magnetic field generator changes from the desired direction.

  Moreover, in the magnetic field generator provided with the several magnetic field generation part each comprised by the permanent magnet, there existed a problem that it was not easy to arrange a several magnetic field generation part in a desired pattern. Hereinafter, this problem will be described in detail with reference to an example of a magnetic field generator that is set so that the magnetization directions of a plurality of magnetic field generators are alternately switched like a scale. In the following description, it is assumed that the magnetization directions of the plurality of magnetic field generation units are alternately switched between the first direction and the second direction. Further, the plurality of magnetic field generation units whose magnetization is set in the first direction are referred to as the plurality of first magnetic field generation units, and the plurality of magnetic field generation units whose magnetization is set in the second direction are the plurality of second magnetic field generation units. It is called a magnetic field generator. The magnetic field generator is manufactured by the following method.

  First, an initial magnetic field generator including a plurality of initial magnetic field generators whose magnetization is not set in a predetermined direction is manufactured. Next, a plurality of initial magnetic field generators that are to be a plurality of first magnetic field generators are applied with a magnetic field in a first direction having a strength equal to or greater than their holding power, and their magnetization is changed to the first. Set to the direction. At that time, a magnetic field having a strength higher than the holding force is not applied to a plurality of initial magnetic field generation units that are to be a plurality of second magnetic field generation units. The plurality of initial magnetic field generators whose magnetizations are set in the first direction become the plurality of first magnetic field generators.

  Next, a plurality of initial magnetic field generators that are to be a plurality of second magnetic field generators are applied with a magnetic field in the second direction having a strength equal to or greater than their holding force, and the magnetizations thereof are changed to the second. Set to the direction. At that time, a magnetic field having a strength higher than the coercive force is not applied to the plurality of first magnetic field generators whose magnetization is already set in the first direction. The plurality of initial magnetic field generation units whose magnetizations are set in the second direction become the plurality of second magnetic field generation units.

  In the above method for producing a magnetic field generator, the strength of the applied magnetic field is greatly varied between two adjacent initial magnetic field generators or between the adjacent first magnetic field generator and the initial magnetic field generator. There was a need. In order to make this possible, it has been necessary to take measures such as increasing the distance between two adjacent magnetic field generators. For this reason, in a magnetic field generator including a plurality of magnetic field generators each composed of a permanent magnet, it is not easy to arrange the plurality of magnetic field generators in a desired pattern.

  In addition, when the distance between two adjacent magnetic field generation units is increased, there are problems that the degree of freedom of arrangement of the plurality of magnetic field generation units decreases and the occupied area of the plurality of magnetic field generation units increases. It was. Furthermore, the change in the external magnetic field between two adjacent magnetic field generators has become gradual, resulting in a problem that the resolution of the magnetic sensor system using the magnetic field generator as a scale is reduced.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a magnetic field generator having a plurality of magnetic field generators arranged in a desired pattern and having high resistance to a disturbance magnetic field, and a magnetic field including the magnetic field generator. It is to provide a sensor system and a magnetic sensor.

  The magnetic field generator of the present invention includes a plurality of magnetic field generators that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. Each of the plurality of magnetic field generators includes a first ferromagnetic part and a first antiferromagnetic part. The first antiferromagnetic part is in contact with the first ferromagnetic part and exchange-coupled with the first ferromagnetic part. The first ferromagnetic part has magnetization as the entire first ferromagnetic part. The plurality of magnetic field generation units include two magnetic field generation units having different magnetization directions as the entire first ferromagnetic body unit.

  In the magnetic field generator of the present invention, the first ferromagnetic part may include a plurality of stacked constituent layers. In this case, the plurality of constituent layers include a first ferromagnetic layer in contact with the first antiferromagnetic part. The plurality of constituent layers may further include a second ferromagnetic layer located farther from the first antiferromagnetic part than the first ferromagnetic layer. The plurality of constituent layers may further include a nonmagnetic layer interposed between the first ferromagnetic layer and the second ferromagnetic layer. The first ferromagnetic layer and the second ferromagnetic layer may be ferromagnetically exchange-coupled via a nonmagnetic layer. In this case, both the first ferromagnetic layer and the second ferromagnetic layer have magnetization in the same direction as the magnetization of the entire first ferromagnetic part. Alternatively, the first ferromagnetic layer and the second ferromagnetic layer may be antiferromagnetically exchange coupled via a nonmagnetic layer. In this case, the second ferromagnetic layer has a magnetization in the same direction as the magnetization of the entire first ferromagnetic part.

  In the magnetic field generator of the present invention, the first ferromagnetic part may have a first surface and a second surface facing away from each other, and the first antiferromagnetic part May be in contact with the first surface of the first ferromagnetic part. In this case, each of the plurality of magnetic field generation units further includes a second antiferromagnetic part that is in contact with the second surface of the first ferromagnetic part and exchange-coupled with the first ferromagnetic part. You may go out. The first antiferromagnetic part and the second antiferromagnetic part may have different blocking temperatures.

  In the magnetic field generator of the present invention, the first antiferromagnetic part may have a first surface and a second surface facing to opposite sides, and the first ferromagnetic part May be in contact with the first surface of the first antiferromagnetic part. In this case, each of the plurality of magnetic field generation units further includes a second ferromagnetic part that is in contact with the second surface of the first antiferromagnetic part and exchange-coupled with the first antiferromagnetic part. May be included. The second ferromagnetic part has magnetization as the entire second ferromagnetic part.

  The magnetic sensor system of the present invention includes a scale and a magnetic sensor that can change the relative positional relationship, and detects a physical quantity related to the relative positional relationship between the scale and the magnetic sensor. The scale is constituted by the magnetic field generator of the present invention.

  In the magnetic sensor system of the present invention, the plurality of magnetic field generators may be arranged in a line. In this case, any two adjacent magnetic field generation units in the plurality of magnetic field generation units may have different magnetization directions as the entire first ferromagnetic body unit. The direction of magnetization of the entire first ferromagnetic body in one of the two adjacent magnetic field generators and the direction of magnetization of the entire first ferromagnetic body in the other are determined by the plurality of magnetic field generators. The rows may extend in the direction in which the rows extend and may be in opposite directions.

  In the magnetic sensor system of the present invention, the plurality of magnetic field generation units may be arranged in an annular shape so as to form an assembly having an outer peripheral part and an inner peripheral part. In this case, any two adjacent magnetic field generation units in the plurality of magnetic field generation units may have different magnetization directions as the entire first ferromagnetic body unit. In addition, the direction of magnetization of the entire first ferromagnetic part in one of the two adjacent magnetic field generation parts may be a direction from the outer peripheral part toward the inner peripheral part, and the first ferromagnetic substance in the other part The direction of magnetization of the entire part may be a direction from the inner peripheral part to the outer peripheral part.

  The magnetic sensor of the present invention includes a plurality of magnetic detection elements that detect a magnetic field to be detected, and a bias magnetic field generator that generates a plurality of bias magnetic fields applied to the plurality of magnetic detection elements. The bias magnetic field generator is constituted by the magnetic field generator of the present invention. Each of the plurality of bias magnetic fields is caused by magnetization of the entire first ferromagnetic body portion in at least one of the plurality of magnetic field generation portions.

  In the magnetic sensor of the present invention, each of the plurality of magnetic detection elements may be a magnetoresistance effect element. The magnetoresistive effect element includes a magnetization fixed layer having magnetization whose direction is fixed, a free layer whose magnetization changes according to a magnetic field to be detected, a nonmagnetic layer disposed between the magnetization fixed layer and the free layer, You may have. In addition, the magnetization direction of the entire first ferromagnetic body portion in any magnetic field generation section among the plurality of magnetic field generation sections is caused by the magnetization of the entire first ferromagnetic body section in the arbitrary magnetic field generation section. The magnetization direction of the magnetization fixed layer of the specific magnetic detection element to which the bias magnetic field is applied may be crossed.

  In the magnetic sensor of the present invention, the plurality of magnetic detection elements may include a first magnetic detection element and a second magnetic detection element connected in series. The first and second magnetic field generators may be included. The bias magnetic field applied to the first magnetic detection element is caused by the magnetization of the entire first ferromagnetic body in the first magnetic field generator. The bias magnetic field applied to the second magnetic detection element is caused by the magnetization of the entire first ferromagnetic body in the second magnetic field generator. The first and second magnetic field generators have different magnetization directions as the entire first ferromagnetic part.

  In the magnetic sensor of the present invention, the plurality of magnetic detection elements may include a first magnetic detection element and a second magnetic detection element connected in series. The 1st thru | or 4th magnetic field generation | occurrence | production part may be included. The bias magnetic field applied to the first magnetic sensing element is the magnetization of the entire first ferromagnetic body in the first magnetic field generator and the entire first ferromagnetic body in the second magnetic field generator. Due to magnetization. The bias magnetic field applied to the second magnetic sensing element is the magnetization of the entire first ferromagnetic member in the third magnetic field generator and the entire first ferromagnetic member in the fourth magnetic field generator. Due to magnetization. The first and third magnetic field generators are adjacent to each other and have different magnetization directions as the entire first ferromagnetic part. The second and fourth magnetic field generators are adjacent to each other and have different magnetization directions as the entire first ferromagnetic part.

  In each magnetic field generator in the magnetic field generator of the present invention, the first antiferromagnetic material portion and the first ferromagnetic material portion are exchange-coupled so that the magnetization direction of the entire first ferromagnetic material portion is changed. It is prescribed. In each magnetic field generator, even if a disturbance magnetic field having a strength that is large enough to reverse the direction of magnetization of the entire first ferromagnetic body is temporarily applied, if such a disturbance magnetic field disappears, the first strong magnetic field is generated. The direction of magnetization of the magnetic part as a whole returns to the original direction. The magnetic field generator of the present invention can be easily produced without increasing the distance between two adjacent magnetic field generators. Therefore, according to the present invention, it is possible to realize a magnetic field generator in which a plurality of magnetic field generators are arranged in a desired pattern and highly resistant to a disturbance magnetic field, and a magnetic sensor system and a magnetic sensor including the magnetic field generator. There is an effect that it becomes possible.

1 is a perspective view showing a schematic configuration of a magnetic sensor system according to a first embodiment of the present invention. It is a perspective view which shows a part of magnetic field generator which concerns on the 1st Embodiment of this invention. It is a side view which shows the 1st example of the magnetic field generation part in the 1st Embodiment of this invention. It is a side view which shows the 2nd example of the magnetic field generation | occurrence | production part in the 1st Embodiment of this invention. It is a side view which shows the 3rd example of the magnetic field generation part in the 1st Embodiment of this invention. It is a side view which shows the 4th example of the magnetic field generation part in the 1st Embodiment of this invention. It is a side view which shows the 5th example of the magnetic field generation | occurrence | production part in the 1st Embodiment of this invention. It is a side view which shows the 7th example of the magnetic field generation | occurrence | production part in the 1st Embodiment of this invention. It is a side view which shows the 8th example of the magnetic field generation part in the 1st Embodiment of this invention. It is a perspective view of the magnetic sensor in the 1st Embodiment of this invention. It is a circuit diagram of the magnetic sensor in the 1st Embodiment of this invention. It is a side view which shows an example of a structure of MR element in the 1st Embodiment of this invention. It is a characteristic view which shows the magnetization curve of a permanent magnet. It is a characteristic view which shows the magnetization curve of a magnetic field generation | occurrence | production part. It is a perspective view which shows the structure of the outline of the magnetic sensor system which concerns on the 2nd Embodiment of this invention. It is a perspective view which shows the structure of the outline of the magnetic sensor system in the 3rd Embodiment of this invention. It is a circuit diagram of the magnetic sensor which concerns on the 3rd Embodiment of this invention. It is sectional drawing which shows a part of magnetic sensor which concerns on the 3rd Embodiment of this invention. It is a side view which shows an example of a structure of MR element and the magnetic field generation part in the 3rd Embodiment of this invention. It is a perspective view which shows the structure of the outline of the modification of the magnetic sensor system in the 3rd Embodiment of this invention. It is a circuit diagram of the magnetic sensor which concerns on the 4th Embodiment of this invention. It is sectional drawing which shows a part of magnetic sensor which concerns on the 4th Embodiment of this invention. It is a circuit diagram of the magnetic sensor which concerns on the 5th Embodiment of this invention. It is a circuit diagram which shows the circuit structure of the magnetic sensor system in the 6th Embodiment of this invention. It is a circuit diagram which shows the circuit structure of the magnetic sensor system in the 7th Embodiment of this invention.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. First, a schematic configuration of a magnetic sensor system according to a first embodiment of the present invention will be described with reference to FIG. The magnetic sensor system according to the present embodiment includes a scale 1 and a magnetic sensor 4 that can change relative positions, and detects a physical quantity related to the relative positional relationship between the scale 1 and the magnetic sensor 4. It is. Scale 1 in the present embodiment is a linear scale configured by magnetic field generator 100 according to the present embodiment. The magnetic field generator 100 includes a plurality of magnetic field generators 200 arranged in a predetermined pattern and generating a plurality of external magnetic fields. In the present embodiment, the plurality of magnetic field generators 200 are arranged in a line.

  In the present embodiment, the direction in which the rows of the plurality of magnetic field generation units 200 extend is defined as the X direction. Two directions perpendicular to the X direction and orthogonal to each other are defined as a Y direction and a Z direction. Note that the X direction, the Y direction, and the Z direction used in the present application are all defined as including a specific direction and the opposite direction, as indicated by a bidirectional arrow in FIG. On the other hand, the direction of the magnetic field and the direction of magnetization are defined as representing only one specific direction.

  Each of the plurality of magnetic field generation units 200 has a rectangular parallelepiped shape, for example. The widths in the X direction of the plurality of magnetic field generators 200 are equal or substantially equal. The scale 1 has a side surface 1a perpendicular to the Z direction. The magnetic sensor 4 is disposed at a position facing the side surface 1 a of the scale 1. One of the scale 1 and the magnetic sensor 4 moves linearly in the X direction in conjunction with an operating body (not shown). As a result, the relative positional relationship between the scale 1 and the magnetic sensor 4 changes. The magnetic sensor system detects the relative position and speed of the scale 1 with respect to the magnetic sensor 4 as a physical quantity related to the relative positional relationship between the scale 1 and the magnetic sensor 4.

  When the relative positional relationship between the scale 1 and the magnetic sensor 4 changes, the magnetic sensor 4 is applied to the magnetic sensor 4 based on a magnetic field to be detected by the magnetic sensor 4, that is, a part of a plurality of external magnetic fields generated by the plurality of magnetic field generators 200. The direction of the applied magnetic field changes. In the example shown in FIG. 1, the X-direction orthogonal projection component of the magnetic field to be detected vibrates at the position where the magnetic sensor 4 is disposed.

  Next, the configuration of the plurality of magnetic field generation units 200 will be described in detail with reference to FIGS. 1 to 3. FIG. 2 is a perspective view showing a part of the magnetic field generator 100. FIG. 3 is a side view showing a first example of the magnetic field generator 200. As shown in FIG. 3, each of the plurality of magnetic field generation units 200 includes a first ferromagnetic body portion 220 and a first antiferromagnetic body portion 210. In the present embodiment, the first ferromagnetic part 220 and the first antiferromagnetic part 210 are stacked along the Y direction. The first ferromagnetic part 220 has a first surface 220a and a second surface 220b that face opposite sides of each other. The first antiferromagnetic portion 210 is in contact with the first surface 220 a of the first ferromagnetic portion 220 and is exchange coupled with the first ferromagnetic portion 220.

  The first ferromagnetic part 220 has magnetization as the entire first ferromagnetic part 220. The magnetization of the entire first ferromagnetic portion 220 is a volume average of the vector sum of magnetic moments of units such as atoms and crystal lattices in the entire first ferromagnetic portion 220. Hereinafter, the magnetization of the first ferromagnetic part 220 as a whole is simply referred to as the magnetization of the first ferromagnetic part 220. A white arrow in FIGS. 1 and 2 represents the direction of magnetization of the first ferromagnetic part 220.

  In the magnetic field generator 100 according to the present embodiment, the first antiferromagnetic part 210 and the first ferromagnetic part 220 are exchange-coupled so that the magnetization direction of the first ferromagnetic part 220 is changed. It is prescribed. Thereby, the magnetic field generator 100 has high resistance to a disturbance magnetic field. This will be described in detail later.

  The plurality of magnetic field generation units 200 include two magnetic field generation units having different magnetization directions of the first ferromagnetic body unit 220. In FIG. 2, reference numerals 200 </ b> A and 200 </ b> B indicate two adjacent magnetic field generators in the plurality of magnetic field generators 200. As shown in FIG. 2, the two magnetic field generators 200 </ b> A and 200 </ b> B are different from each other in the magnetization direction of the first ferromagnetic body 220. In the present embodiment, in particular, the direction of magnetization of the first ferromagnetic body 220 in the magnetic field generator 200A and the direction of magnetization of the first ferromagnetic body 220 in the magnetic field generator 200B are a plurality of magnetic field generators. The 200 rows cross in the extending direction (X direction) and are opposite to each other.

  Here, as shown in FIG. 2, a first direction D1 and a second direction D2 are defined. In the present embodiment, each of the first and second directions D1 and D2 is a specific direction parallel to the Z direction. In FIG. 2, the first direction D1 is a direction toward the lower left side. The second direction D2 is a direction opposite to the first direction D1. In the example shown in FIG. 2, the magnetization direction of the first ferromagnetic body portion 220 in the magnetic field generation portion 200A is the first direction D1. The direction of magnetization of the first ferromagnetic body 220 in the magnetic field generator 200B is the second direction D2.

  The first ferromagnetic part 220 may be constituted by one ferromagnetic layer or may include a plurality of laminated constituent layers. The first example of the magnetic field generation unit 200 shown in FIG. 3 is an example in the case where the first ferromagnetic body unit 220 is configured by one ferromagnetic layer. In the first example, the first ferromagnetic part 220 (ferromagnetic layer) is formed of a ferromagnetic material containing one or more elements of Co, Fe, and Ni. Examples of such a ferromagnetic material include CoFe, CoFeB, and CoNiFe. The first antiferromagnetic part 210 is made of an antiferromagnetic material such as IrMn or PtMn.

  Hereinafter, second to eighth examples of the magnetic field generation unit 200 will be described with reference to FIGS. 4 to 9. Each of the second to eighth examples is an example in which the first ferromagnetic portion 220 includes a plurality of stacked constituent layers.

  FIG. 4 shows a second example of the magnetic field generator 200. In the second example, the first ferromagnetic layer 221 in contact with the first antiferromagnetic part 210 and the first ferromagnetic layer 221 are included in the plurality of constituent layers of the first ferromagnetic part 220. Also, the second ferromagnetic layer 222 located farther from the first antiferromagnetic part 210 is included. Both the first ferromagnetic layer 221 and the second ferromagnetic layer 222 have magnetization in the same direction as the magnetization of the first ferromagnetic body 220. In FIG. 4, white arrows in the first and second ferromagnetic layers 221 and 222 indicate the magnetization directions of the first and second ferromagnetic layers 221 and 222. In the same view as FIG. 4 used in the following description, the magnetization direction of the ferromagnetic layers such as the first and second ferromagnetic layers 221 and 222 is expressed in the same way as in FIG. Use.

  In order to increase the external magnetic field generated by the magnetic field generation unit 200 and to reduce the size of the magnetic field generation unit 200, the first ferromagnetic body unit 220 includes a ferromagnetic layer formed of a ferromagnetic material having a high saturation magnetic flux density. It is preferable to contain. However, such a ferromagnetic layer does not necessarily have a large exchange coupling energy with the first antiferromagnetic material portion 210. Therefore, in the second example, the first ferromagnetic layer 221 is formed of a ferromagnetic material capable of increasing the exchange coupling energy with the first antiferromagnetic material portion 210, and the second ferromagnetic layer is formed. 222 is preferably formed of a ferromagnetic material having a saturation magnetic flux density higher than that of the ferromagnetic material constituting the first ferromagnetic layer 221. Accordingly, the external magnetic field generated by the magnetic field generation unit 200 is increased while the exchange coupling energy between the first ferromagnetic unit 220 and the first antiferromagnetic unit 210 is increased, and the magnetic field generation unit 200 is reduced in size. Can be An example of the first ferromagnetic layer 221 is a CoFe layer. An example of the second ferromagnetic layer 222 is an Fe layer.

  FIG. 5 shows a third example of the magnetic field generator 200. In the third example, the first and second ferromagnetic layers 221 and 222 are included in the plurality of constituent layers of the first ferromagnetic body portion 220 as in the second example. The first ferromagnetic layer 221 and the second ferromagnetic layer 222 may be formed of the same ferromagnetic material, or may be formed of different ferromagnetic materials.

  The plurality of constituent layers in the third example further includes a nonmagnetic layer 224 interposed between the first ferromagnetic layer 221 and the second ferromagnetic layer 222. For example, Ru is used as the material of the nonmagnetic layer 224. In the third example, the first ferromagnetic layer 221 and the second ferromagnetic layer 222 are ferromagnetically exchange-coupled via the nonmagnetic layer 224 so that their magnetization directions are the same. Yes. Both the first ferromagnetic layer 221 and the second ferromagnetic layer 222 have magnetization in the same direction as the magnetization of the first ferromagnetic body 220. The thickness of the nonmagnetic layer 224 is set such that the exchange coupling between the first ferromagnetic layer 221 and the second ferromagnetic layer 222 does not disappear.

  FIG. 6 shows a fourth example of the magnetic field generator 200. In the fourth example, the first ferromagnetic layer 221, the second ferromagnetic layer 222, and the nonmagnetic layer 224 are included in the plurality of constituent layers of the first ferromagnetic part 220, as in the third example. It is included. In the fourth example, the first ferromagnetic layer 221 and the second ferromagnetic layer 222 are antiferromagnetically exchange-coupled via the nonmagnetic layer 224 so that their magnetization directions are opposite to each other. doing. The first ferromagnetic layer 221 has a magnetization in a direction opposite to the magnetization of the first ferromagnetic body portion 220, and the second ferromagnetic layer 222 has the same magnetization as the first ferromagnetic body portion 220. It has direction magnetization.

  In the fourth example, the sum of magnetic moments per unit in the entire second ferromagnetic layer 222 is larger than the sum of magnetic moments per unit in the entire first ferromagnetic layer 221. Therefore, in the fourth example, the magnetization direction of the first ferromagnetic body portion 220 matches the magnetization direction of the second ferromagnetic layer 222.

An example of the first ferromagnetic layer 221 is a Co ₉₀ Fe ₁₀ layer. An example of the second ferromagnetic layer 222 is a Co ₃₀ Fe ₇₀ layer. Co ₉₀ Fe ₁₀ represents an alloy composed of 90 atomic percent Co and 10 atomic percent Fe, and Co ₃₀ Fe ₇₀ represents an alloy composed of 30 atomic percent Co and 70 atomic percent Fe. The thickness of the second ferromagnetic layer 222 is preferably larger than the thickness of the first ferromagnetic layer 221.

  In the fourth example, the exchange coupling energy of the first ferromagnetic layer 221 and the second ferromagnetic layer 222 that are antiferromagnetically coupled is the same as that of the first antiferromagnetic material portion 210 and the first ferromagnetic layer. It may be larger than the exchange coupling energy of 221. In this case, the magnetization fixing force of the second ferromagnetic layer 222 can be increased, and as a result, the resistance of the magnetic field generator 100 to a disturbance magnetic field can be increased.

  FIG. 7 shows a fifth example of the magnetic field generator 200. In the fifth example, each of the plurality of magnetic field generation units 200 includes the second ferromagnetic material portion 220 in addition to the first ferromagnetic material portion 220 and the first antiferromagnetic material portion 210. A second antiferromagnetic portion 230 that is in contact with the surface 220b and exchange-coupled with the first ferromagnetic portion 220 is included. As the antiferromagnetic material forming the second antiferromagnetic material portion 230, for example, the same antiferromagnetic material as that of the first antiferromagnetic material portion 210 in the first example is used. Particularly in the fifth example, the first antiferromagnetic portion 210 and the second antiferromagnetic portion 230 are formed of the same antiferromagnetic material.

  Further, in the fifth example, the first and second ferromagnetic layers 221 and 222 are included in the plurality of constituent layers of the first ferromagnetic body portion 220 as in the second example. The plurality of constituent layers in the fifth example are further located farther from the first antiferromagnetic part 210 than the first and second ferromagnetic layers 221 and 222, and the second antiferromagnetic A third ferromagnetic layer 223 in contact with the body part 230 is included. The first ferromagnetic layer 221, the second ferromagnetic layer 222, and the third ferromagnetic layer 223 all have magnetization in the same direction as the magnetization of the first ferromagnetic body portion 220. In the fifth example, the first and third ferromagnetic layers 221 and 223 are formed of a ferromagnetic material capable of increasing the exchange coupling energy with the first and second antiferromagnetic parts 210 and 230. The second ferromagnetic layer 222 is preferably formed of a ferromagnetic material having a saturation magnetic flux density higher than that of the ferromagnetic materials constituting the first and third ferromagnetic layers 221 and 223. Examples of the first and third ferromagnetic layers 221 and 223 include a CoFe layer. An example of the second ferromagnetic layer 222 is an Fe layer.

  The direction of magnetization of the first ferromagnetic part 220 is defined by the exchange coupling between the first and second antiferromagnetic parts 210 and 230 and the first ferromagnetic part 220. In the fifth example, the magnetization fixing force of the first ferromagnetic part 220 is stronger than the case where the magnetic field generation part 200 includes only the first antiferromagnetic part 210 and the first ferromagnetic part 220. As a result, the resistance of the magnetic field generator 100 to a disturbance magnetic field can be increased.

  In the fifth example, instead of the first ferromagnetic part 220 shown in FIG. 7, the first ferromagnetic part 220 in the first example shown in FIG. 3 may be used. Also in this case, the direction of magnetization of the first ferromagnetic part 220 is defined by the exchange coupling between the first and second antiferromagnetic parts 210 and 230 and the first ferromagnetic part 220. The

  Next, a sixth example of the magnetic field generator 200 will be described. The configuration of the magnetic field generator 200 in the sixth example is basically the same as that of the magnetic field generator 200 in the fifth example shown in FIG. However, in the sixth example, the first antiferromagnetic part 210 and the second antiferromagnetic part 230 have different blocking temperatures.

  The operation and effect of the sixth example will be described below. Here, the first antiferromagnetic part 210 is an IrMn layer, the second antiferromagnetic part 230 is a PtMn layer, and the first and third ferromagnetic layers 221 and 223 are CoFe layers. A case will be described as an example. In this case, the coupling force between the first antiferromagnetic part 210 and the first ferromagnetic layer 221 is stronger than the coupling force between the second antiferromagnetic part 230 and the third ferromagnetic layer 223. On the other hand, the second antiferromagnetic part 230 (PtMn layer) has a higher blocking temperature than the first antiferromagnetic part 210 (IrMn layer). In this case, when the temperature of the magnetic field generation unit 200 exceeds the blocking temperature of the first antiferromagnetic material part 210, exchange coupling between the first antiferromagnetic material part 210 and the first ferromagnetic layer 221 is performed. Disappears. However, if the temperature of the magnetic field generating unit 200 is lower than the blocking temperature of the second antiferromagnetic material unit 230, exchange coupling between the second antiferromagnetic material unit 230 and the third ferromagnetic layer 223 is performed. Does not disappear, and the magnetization direction of the first ferromagnetic part 220 does not change. After that, when the temperature of the magnetic field generation unit 200 becomes lower than the blocking temperature of the first antiferromagnetic body part 210, the magnetization direction of the first ferromagnetic body part 220 is maintained and the first antiferromagnetic material is maintained. Strong coupling between the body part 210 and the first ferromagnetic layer 221 is restored. From the above, according to the sixth example, it is possible to realize the magnetic field generator 100 in which the magnetization direction of the first ferromagnetic body portion 220 hardly changes even when exposed to a high temperature.

  FIG. 8 shows a seventh example of the magnetic field generator 200. In the seventh example, each of the plurality of magnetic field generation units 200 is similar to the fifth example in that the first ferromagnetic part 220, the first antiferromagnetic part 210, and the second antiferromagnetic substance. Part 230 is included. The plurality of constituent layers of the first ferromagnetic part 220 include first to third ferromagnetic layers 221, 222, and 223, as in the fifth example. The ferromagnetic materials constituting the first to third ferromagnetic layers 221 to 223 may all be the same, may all be different, or may be the same.

  The plurality of constituent layers in the seventh example further include a nonmagnetic layer 224 interposed between the first ferromagnetic layer 221 and the second ferromagnetic layer 222, and a second ferromagnetic layer 222. And a nonmagnetic layer 225 interposed between the first ferromagnetic layer 223 and the third ferromagnetic layer 223. For example, Ru is used as the material of the nonmagnetic layers 224 and 225. The first ferromagnetic layer 221 and the second ferromagnetic layer 222 are antiferromagnetically exchange-coupled via the nonmagnetic layer 224. The second ferromagnetic layer 222 and the third ferromagnetic layer 223 are antiferromagnetically exchange coupled via the nonmagnetic layer 225. The first and third ferromagnetic layers 221 and 223 have magnetization in a direction opposite to the magnetization of the first ferromagnetic part 220, and the second ferromagnetic layer 222 has the first ferromagnetic part It has magnetization in the same direction as 220 magnetization.

  In the seventh example, the sum of magnetic moments per unit in the entire second ferromagnetic layer 222 is larger than the sum of magnetic moments per unit in the entire first and third ferromagnetic layers 221 and 223. Therefore, in the seventh example, the magnetization direction of the first ferromagnetic body portion 220 coincides with the magnetization direction of the second ferromagnetic layer 222.

  FIG. 9 shows an eighth example of the magnetic field generator 200. In the eighth example, each of the plurality of magnetic field generation units 200 is similar to the fifth example in that the first ferromagnetic part 220, the first antiferromagnetic part 210, and the second antiferromagnetic substance. Part 230 is included. The plurality of constituent layers of the first ferromagnetic part 220 include first to third ferromagnetic layers 221, 222, and 223, as in the fifth example. The ferromagnetic materials constituting the first to third ferromagnetic layers 221 to 223 may all be the same, may all be different, or may be the same.

  The first antiferromagnetic part 210 has a first surface 210a and a second surface 210b that face in opposite directions. The first ferromagnetic part 220 is in contact with the first surface 210 a of the first antiferromagnetic part 210. Each of the plurality of magnetic field generation units 200 in the eighth example further contacts the second surface 210b of the first antiferromagnetic body 210 and exchange-couples with the first antiferromagnetic body 210. The ferromagnetic part 240 is included. The second ferromagnetic part 240 has the magnetization of the second ferromagnetic part 240 as a whole. Hereinafter, the magnetization of the second ferromagnetic part 240 as a whole is simply referred to as the magnetization of the second ferromagnetic part 240. The direction of magnetization of the second ferromagnetic part 240 is the same as the direction of magnetization of the first ferromagnetic part 220.

  The second ferromagnetic body 240 has a first surface 240a and a second surface 240b that face opposite sides of each other. The first surface 240 a of the second ferromagnetic part 240 is in contact with the second surface 210 b of the first antiferromagnetic part 210. Each of the plurality of magnetic field generation units 200 in the eighth example further contacts the second surface 240b of the second ferromagnetic body 240 and exchanges and couples with the second ferromagnetic body 240. A ferromagnetic part 250 is included. The antiferromagnetic materials constituting the first to third antiferromagnetic parts 210, 230, and 250 may be all the same, may be all different, or two may be the same.

  The second ferromagnetic part 240 includes a plurality of stacked constituent layers. The plurality of constituent layers include a first ferromagnetic layer 241 in contact with the first antiferromagnetic part 210 and a position farther from the first antiferromagnetic part 210 than the first ferromagnetic layer 241. A certain second ferromagnetic layer 242 and a position farther from the first antiferromagnetic part 210 than the first and second ferromagnetic layers 241 and 242 are in contact with the third antiferromagnetic part 250. A third ferromagnetic layer 243 is included. The ferromagnetic materials constituting the first to third ferromagnetic layers 241 to 243 may all be the same, may all be different, or may be the same.

  The magnetic field generator 200 of the eighth example includes two ferromagnetic parts 220 and 240 having magnetization in the same direction. Thereby, according to the 8th example, the tolerance of magnetic field generating body 100 to a disturbance magnetic field can be raised. In the eighth example, the magnetization directions of the two ferromagnetic parts 220 and 240 can be defined in the same direction by one antiferromagnetic part 210. Therefore, in the eighth example, the two ferromagnetic parts 220 and 240 having the magnetization in the same direction can be efficiently manufactured.

  In the eighth example, instead of the first ferromagnetic part 220 shown in FIG. 9, the first ferromagnetic part 220 in the first example shown in FIG. 3 may be used. The first ferromagnetic part 220 in the seventh example shown in FIG. Further, instead of the second ferromagnetic portion 240 shown in FIG. 9, a ferromagnetic portion having the same configuration as that of the first ferromagnetic portion 220 in the first example shown in FIG. 3 may be used. Alternatively, a ferromagnetic part having the same configuration as that of the first ferromagnetic part 220 in the seventh example shown in FIG. 8 may be used. Further, the configuration of the magnetic field generation unit 200 in the present embodiment may be a configuration in which the second and third antiferromagnetic parts 230 and 250 are excluded from the configuration of the magnetic field generation unit 200 shown in FIG. .

  Next, an example of the configuration of the magnetic sensor 4 in the present embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a perspective view of the magnetic sensor 4. FIG. 11 is a circuit diagram of the magnetic sensor 4. The magnetic sensor 4 includes four magnetoresistive elements (hereinafter referred to as MR elements) 10A, 10B, 10C, 10D, a substrate (not shown), two upper electrodes 31, 32, and two lower electrodes 41, 42. And. The lower electrodes 41 and 42 are disposed on a substrate (not shown).

  The upper electrode 31 has a base portion 310 and branch portions 311 and 312 that are bifurcated from the base portion 310. The upper electrode 32 has a base part 320 and branch parts 321 and 322 that are bifurcated from the base part 320. The lower electrode 41 includes a base portion 410 and branch portions 411 and 412 that are bifurcated from the base portion 410. The lower electrode 42 includes a base portion 420 and branch portions 421 and 422 that are bifurcated from the base portion 420. The branch part 311 of the upper electrode 31 faces the branch part 411 of the lower electrode 41. The branch part 312 of the upper electrode 31 faces the branch part 421 of the lower electrode 42. The branch part 321 of the upper electrode 32 faces the branch part 412 of the lower electrode 41. The branch part 322 of the upper electrode 32 faces the branch part 422 of the lower electrode 42.

  The MR element 10 </ b> A is disposed between the branch part 411 of the lower electrode 41 and the branch part 311 of the upper electrode 31. The MR element 10 </ b> B is disposed between the branch part 421 of the lower electrode 42 and the branch part 312 of the upper electrode 31. The MR element 10 </ b> C is disposed between the branch part 422 of the lower electrode 42 and the branch part 322 of the upper electrode 32. The MR element 10 </ b> D is disposed between the branch portion 412 of the lower electrode 41 and the branch portion 321 of the upper electrode 32.

  As shown in FIG. 10, the base 310 of the upper electrode 31 includes a first output port E1. The base 320 of the upper electrode 32 includes a second output port E2. The base 410 of the lower electrode 41 includes a power supply port V. The base 420 of the lower electrode 42 includes a ground port G.

  The MR element 10A and the MR element 10B are connected in series via the upper electrode 31. MR element 10 </ b> C and MR element 10 </ b> D are connected in series via upper electrode 32.

  As shown in FIG. 11, one end of the MR element 10 </ b> A is connected to the power supply port V. The other end of the MR element 10A is connected to the first output port E1. One end of the MR element 10B is connected to the first output port E1. The other end of the MR element 10B is connected to the ground port G. The MR elements 10A and 10B constitute a half bridge circuit. One end of the MR element 10C is connected to the second output port E2. The other end of the MR element 10C is connected to the ground port G. One end of the MR element 10D is connected to the power supply port V. The other end of the MR element 10D is connected to the second output port E2. The MR elements 10C and 10D constitute a half bridge circuit. MR elements 10A, 10B, 10C and 10D constitute a Wheatstone bridge circuit.

  A power supply voltage having a predetermined magnitude is applied to the power supply port V. The ground port G is connected to the ground. The resistance values of the MR elements 10A, 10B, 10C, and 10D change according to the magnetic field to be detected. The resistance values of the MR elements 10A and 10C change with the same phase. The resistance values of the MR elements 10B and 10D change at a phase different from the resistance values of the MR elements 10A and 10C by 180 °. The first output port E1 outputs a first detection signal corresponding to the potential at the connection point of the MR elements 10A and 10B. The second output port E2 outputs a second detection signal corresponding to the potential at the connection point of the MR elements 10D and 10C. The first and second detection signals change according to the magnetic field to be detected. The second detection signal is 180 degrees out of phase with the first detection signal. The output signal of the magnetic sensor 4 is generated by an operation including obtaining a difference between the first detection signal and the second detection signal. For example, the output signal of the magnetic sensor 4 is generated by adding a predetermined offset voltage to a signal obtained by subtracting the second detection signal from the first detection signal. The output signal of the magnetic sensor 4 changes according to the magnetic field to be detected.

  Next, an example of the configuration of the MR elements 10A to 10D will be described with reference to FIG. FIG. 12 is a side view showing an example of the configuration of the MR elements 10A to 10D. In the following description, arbitrary MR elements, upper electrodes, and lower electrodes are denoted by reference numerals 10, 30, and 40, respectively. In the present embodiment, a spin valve type MR element is used as the MR element 10. The MR element 10 is disposed between at least a magnetization fixed layer 13 having magnetization whose direction is fixed, a free layer 15 whose magnetization changes according to a magnetic field to be detected, and between the magnetization fixed layer 13 and the free layer 15. And a nonmagnetic layer 14.

  In the example shown in FIG. 12, the MR element 10 further includes a base layer 11, an antiferromagnetic layer 12, and a protective layer 16. In this example, the underlayer 11, the antiferromagnetic layer 12, the magnetization fixed layer 13, the nonmagnetic layer 14, the free layer 15 and the protective layer 16 are laminated in this order from the lower electrode 40 side along the Z direction. . The underlayer 11 and the protective layer 16 have conductivity. The underlayer 11 is used to eliminate the influence of the crystal axis of the substrate (not shown) and improve the crystallinity and orientation of each layer formed on the underlayer 11. For example, Ta or Ru is used as the material of the base layer 11. The antiferromagnetic layer 12 is a layer that fixes the magnetization direction in the magnetization fixed layer 13 by exchange coupling with the magnetization fixed layer 13. The antiferromagnetic layer 12 is made of an antiferromagnetic material such as IrMn or PtMn.

  In the magnetization fixed layer 13, the magnetization direction is fixed by exchange coupling with the antiferromagnetic layer 12. In the example shown in FIG. 12, the magnetization fixed layer 13 includes an outer layer 131, a nonmagnetic intermediate layer 132, and an inner layer 133 that are sequentially stacked on the antiferromagnetic layer 12, and is a so-called synthetic fixed layer. Yes. The outer layer 131 and the inner layer 133 are formed of a ferromagnetic material such as CoFe, CoFeB, or CoNiFe, for example. The direction of magnetization of the outer layer 131 is fixed by exchange coupling with the antiferromagnetic layer 12. The outer layer 131 and the inner layer 133 are antiferromagnetically coupled, and the magnetization directions are fixed in opposite directions. The nonmagnetic intermediate layer 132 causes antiferromagnetic exchange coupling between the outer layer 131 and the inner layer 133, and fixes the magnetization direction of the outer layer 131 and the magnetization direction of the inner layer 133 in opposite directions. The nonmagnetic intermediate layer 132 is made of a nonmagnetic material such as Ru. When the magnetization fixed layer 13 includes the outer layer 131, the nonmagnetic intermediate layer 132, and the inner layer 133, the magnetization direction of the magnetization fixed layer 13 refers to the magnetization direction of the inner layer 133.

  When the MR element 10 is a TMR element, the nonmagnetic layer 14 is a tunnel barrier layer. The tunnel barrier layer may be formed, for example, by oxidizing a part or the whole of the magnesium layer. When the MR element 10 is a GMR element, the nonmagnetic layer 14 is a nonmagnetic conductive layer. The free layer 15 is made of a soft magnetic material such as CoFe, CoFeB, NiFe, or CoNiFe, for example. The protective layer 16 is a layer for protecting each layer below it. As a material of the protective layer 16, Ta, Ru, W, Ti, or the like is used.

  The foundation layer 11 is connected to the lower electrode 40, and the protective layer 16 is connected to the upper electrode 30. The MR element 10 is supplied with current by the lower electrode 40 and the upper electrode 30. This current flows in a direction intersecting the plane of each layer constituting the MR element 10, for example, a Z direction which is a direction perpendicular to the plane of each layer constituting the MR element 10.

  In the MR element 10, the magnetization of the free layer 15 changes according to the magnetic field applied to the free layer 15. More specifically, the magnetization direction and magnitude of the free layer 15 change according to the direction and magnitude of the magnetic field applied to the free layer 15. The resistance value of the MR element 10 varies depending on the direction and magnitude of the magnetization of the free layer 15. For example, when the magnitude of the magnetization of the free layer 15 is constant, the resistance value of the MR element 10 becomes the minimum value when the magnetization direction of the free layer 15 is the same as the magnetization direction of the magnetization fixed layer 13. When the magnetization direction of the free layer 15 is opposite to the magnetization direction of the magnetization fixed layer 13, the resistance value of the MR element 10 becomes the maximum value.

  FIG. 10 shows an example in which the MR element 10 has a cylindrical shape. However, the MR element 10 may have another shape such as a rectangular parallelepiped shape.

  Next, with reference to FIG. 10 and FIG. 11, the direction of magnetization of the magnetization fixed layer 13 of each of the MR elements 10A to 10D will be described. 10 and 11, solid arrows in the MR elements 10A to 10D indicate the magnetization directions of the magnetization fixed layer 13 in the MR elements 10A to 10D. Here, as shown in FIGS. 10 and 11, a third direction D3 and a fourth direction D4 are defined. In the present embodiment, each of the third and fourth directions D3 and D4 is a specific direction parallel to the X direction. 10 and 11, the third direction D3 is a direction toward the right side. The fourth direction D4 is a direction opposite to the third direction D3.

  As shown in FIGS. 10 and 11, the magnetization direction of the magnetization fixed layer 13 in the MR element 10A is the fourth direction D4, and the magnetization direction of the magnetization fixed layer 13 in the MR element 10B is the third direction D4. The direction is D3. In this case, the potential at the connection point of the MR elements 10A and 10B changes according to the strength of the magnetic field component to be detected in the direction parallel to the third and fourth directions D3 and D4, that is, in the X direction. The first output port E1 outputs a first detection signal corresponding to the potential at the connection point of the MR elements 10A and 10B. The first detection signal represents the intensity of the magnetic field component to be detected in the X direction.

  Also, as shown in FIGS. 10 and 11, the magnetization direction of the magnetization fixed layer 13 in the MR element 10C is the fourth direction D4, and the magnetization direction of the magnetization fixed layer 13 in the MR element 10D is the first direction D4. 3 direction D3. In this case, the potential at the connection point of the MR elements 10C and 10D changes according to the strength of the magnetic field component to be detected in the direction parallel to the third and fourth directions D3 and D4, that is, in the X direction. The second output port E2 outputs a second detection signal corresponding to the potential at the connection point of the MR elements 10C and 10D. The second detection signal represents the intensity of the magnetic field component to be detected in the X direction.

  In the MR element 10A and the MR element 10D, the magnetization directions of the magnetization fixed layer 13 included in them are opposite to each other. In the MR element 10B and the MR element 10C, the magnetization directions of the magnetization fixed layer 13 included in the MR element 10B and the MR element 10C are opposite to each other. Therefore, the phase difference between the second detection signal and the first detection signal is 180 °.

  Note that the magnetization direction of the magnetization fixed layer 13 in the MR elements 10A to 10D may be slightly deviated from the above-mentioned direction from the viewpoint of the accuracy of manufacturing the MR element.

  Next, operations and effects of the magnetic field generator 100 and the magnetic sensor system according to the present embodiment will be described. In the present embodiment, each of the plurality of magnetic field generation units 200 includes a first ferromagnetic part 220 and a first antiferromagnetic part 210, and the first antiferromagnetic part 210 includes It is exchange coupled with one ferromagnetic part 220. Thereby, the direction of magnetization of the first ferromagnetic part 220 is defined.

  Here, the effects of the magnetic field generator 100 and the magnetic sensor system according to the present embodiment will be described in comparison with the magnetic field generator and the magnetic sensor system of the comparative example. The magnetic field generator of the comparative example is a magnetic field generator provided with a plurality of magnetic field generators each formed of a permanent magnet instead of the plurality of magnetic field generators 200 in the present embodiment. The magnetic sensor system of the comparative example is a magnetic sensor system using the magnetic field generator of the comparative example instead of the magnetic field generator 100 according to the present embodiment.

  First, referring to FIG. 13 and FIG. 14, the magnetization curve of the permanent magnet and the magnetization curve of the magnetic field generator 200 are compared. FIG. 13 is a characteristic diagram showing a magnetization curve of a permanent magnet. FIG. 14 is a characteristic diagram showing a magnetization curve of one magnetic field generation unit 200. 13 and 14, the horizontal axis indicates the magnetic field, and the vertical axis indicates the magnetization. For both the magnetic field and the magnetization, the magnitude in a predetermined direction is represented by a positive value, and the magnitude in a direction opposite to the predetermined direction is represented by a negative value. An arrow in the magnetization curve represents the direction of change of the magnetic field. Further, the magnetic field range indicated by reference sign HS represents the magnetic field range to be detected.

  The magnetic sensor system of the comparative example is used under the condition that the strength of the magnetic field to be detected does not exceed the coercive force of the permanent magnet. However, since the magnetic sensor system can be used in various environments, a disturbance magnetic field having a strength exceeding the coercive force of the permanent magnet may be temporarily applied to the permanent magnet. When a disturbance magnetic field with a strength exceeding the coercive force of the permanent magnet is temporarily applied to the permanent magnet, the magnetization direction of the permanent magnet changes from the original direction, and changes from the original direction even if the disturbance magnetic field disappears. May remain. For example, as shown in FIG. 13, when a disturbance magnetic field having a positive value exceeding the range HS of the magnetic field to be detected is temporarily applied to the permanent magnet, after the disturbance magnetic field disappears, the permanent magnet The direction of magnetization is fixed in the positive direction. On the other hand, when a disturbance magnetic field having a negative value exceeding the range HS of the magnetic field to be detected is temporarily applied to the permanent magnet, the magnetization direction of the permanent magnet becomes negative after the disturbance magnetic field disappears. Fixed. For this reason, in the magnetic sensor system of the comparative example, when a disturbance magnetic field having a strength exceeding the coercive force of the permanent magnet is temporarily applied to the permanent magnet, the direction of the magnetic field generated by the magnetic field generator is desired. It may change from the direction.

  On the other hand, in the magnetic field generation unit 200 according to the present embodiment, as can be understood from FIG. Even if such a disturbance magnetic field disappears, the magnetization direction of the first ferromagnetic body portion 220 returns to the original direction. Thus, the magnetic field generator 100 according to the present embodiment is highly resistant to disturbance magnetic fields. This effect is enhanced by providing the magnetic field generation unit 200 with a plurality of antiferromagnetic parts as in the fifth to eighth examples of the magnetic field generation unit 200.

  Further, the magnetic field generator 100 according to the present embodiment can be easily manufactured without increasing the distance between two adjacent magnetic field generators 200. The magnetic field generator 100 according to the present embodiment is manufactured by the following first and second methods, for example. First, the first method will be described. In the first method, a plurality of magnetic field generators 200A (see FIG. 2) in which the magnetization of the first ferromagnetic body 220 is set in the first direction D1, and the magnetization of the first ferromagnetic body 220 are A plurality of magnetic field generation units 200B (see FIG. 2) set in the second direction D2 are formed in separate steps. The formation of the plurality of magnetic field generation units 200A is performed while applying a magnetic field in the first direction D1. As a result, the magnetization of the first ferromagnetic body 220 in each of the plurality of magnetic field generators 200A is set in the first direction D1. Similarly, the formation of the plurality of magnetic field generation units 200B is performed while applying a magnetic field in the second direction D2. Thereby, the magnetization of the first ferromagnetic body 220 in each of the plurality of magnetic field generators 200B is set in the second direction D2.

  Here, for example, consider a case where a plurality of magnetic field generation units 200A are formed in the previous step and a plurality of magnetic field generation units 200B are formed in the subsequent step. In this case, in the step of forming the plurality of magnetic field generation units 200B, a magnetic field in the second direction D2 is applied to the plurality of already formed magnetic field generation units 200A. At this time, even if the magnetization directions of the first ferromagnetic portions 220 of the plurality of magnetic field generators 200A are temporarily reversed, if the magnetic field in the second direction D2 disappears, the plurality of magnetic field generators 200A The direction of magnetization of the first ferromagnetic part 220 returns to the first direction D1.

  Next, the second method will be described. In the second method, first, an initial magnetic field generator including a plurality of initial magnetic field generators in which the magnetization of the first ferromagnetic body 220 is not set in a predetermined direction is manufactured. The plurality of initial magnetic field generators include a plurality of first initial magnetic field generators that are to be a plurality of magnetic field generators 200A and a plurality of second initial magnetic field generators that are to be a plurality of magnetic field generators 200B. include.

  Next, while applying the magnetic field in the first direction D1 to each of the plurality of first initial magnetic field generating units, the temperature of each of the plurality of first initial magnetic field generating units is set to the plurality of first initial magnetic field generating units. The temperature is raised to a temperature higher than the blocking temperature of the antiferromagnetic material part 210 included in each of the magnetic field generating parts, and then lowered. Accordingly, the magnetization of the first ferromagnetic body 220 in each of the plurality of first initial magnetic field generation units is set in the first direction D1, and the plurality of first initial magnetic field generation units is a plurality of magnetic field generation units. 200A.

  Next, while applying the magnetic field in the second direction D2 to each of the plurality of second initial magnetic field generation units, the temperature of each of the plurality of second initial magnetic field generation units is set to the plurality of second initial magnetic field generation units. The temperature is raised to a temperature higher than the blocking temperature of the antiferromagnetic material part 210 included in each of the magnetic field generating parts, and then lowered. As a result, the magnetization of the first ferromagnetic body 220 in each of the plurality of second initial magnetic field generation units is set in the second direction D2, and the plurality of second initial magnetic field generation units is a plurality of magnetic field generation units. 200B. Note that the plurality of magnetic field generation units 200A may be formed after the formation of the plurality of magnetic field generation units 200B.

  In either of the first method and the second method, the first of each of the two adjacent magnetic field generators 200 can be easily obtained without increasing the distance between the two adjacent magnetic field generators 200. It is possible to set the direction of magnetization of the ferromagnetic part 220.

  From the above, according to the present embodiment, a magnetic field generator 100 in which a plurality of magnetic field generators 200 are arranged in a desired pattern and has high resistance to a disturbance magnetic field, and a magnetic sensor system including the magnetic field generator 100 Can be realized. In addition, according to the present embodiment, the resolution of the magnetic sensor system can be improved by reducing the distance between two adjacent magnetic field generation units 200.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 15 is a perspective view showing a schematic configuration of the magnetic sensor system according to the present embodiment. The magnetic sensor system according to the present embodiment is different from the first embodiment in the following points. The magnetic sensor system according to the present embodiment includes a scale 2 instead of the scale 1 in the first embodiment. The scale 2 is an annular rotating scale configured with the magnetic field generator 300 according to the present embodiment. The magnetic field generator 300 includes a plurality of magnetic field generators 400 that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. The plurality of magnetic field generators 400 are arranged in an annular shape so as to form an assembly having an outer peripheral part 300a and an inner peripheral part 300b. The outer peripheral part 300 a is also the outer peripheral part of the magnetic field generator 300. The inner peripheral part 300 b is also an inner peripheral part of the magnetic field generator 300.

  The shape of the plurality of magnetic field generators 400 is, for example, a shape obtained by cutting a thick cylinder by one or more planes passing through the central axis C of the cylinder and dividing it into N equal parts (N is an even number of 2 or more). It is. In the example illustrated in FIG. 15, N, that is, the number of the plurality of magnetic field generation units 400 is six.

  The magnetic sensor 4 is disposed at a position facing the outer peripheral portion 300a. The scale 2 rotates in the rotation direction D around the central axis C in conjunction with an operating body (not shown) that performs a rotating operation. As a result, the relative positional relationship between the scale 2 and the magnetic sensor 4 changes in the rotation direction D. The magnetic sensor system detects a physical quantity related to the relative positional relationship between the scale 2 and the magnetic sensor 4. Specifically, the magnetic sensor system detects a rotation position, a rotation speed, and the like of the operating body that is linked to the scale 2 as the physical quantity.

  The internal configuration of each of the plurality of magnetic field generation units 400 is the same as the internal configuration of each of the plurality of magnetic field generation units 200 in the first embodiment. That is, each of the plurality of magnetic field generation units 400 includes a first ferromagnetic part and a first antiferromagnetic part. The first ferromagnetic part and the first antiferromagnetic part are stacked along a direction parallel to the central axis C. The other configuration of the magnetic field generator 400 is the same as that of any of the first to eighth examples of the magnetic field generator 200 described in the first embodiment.

  In FIG. 15, the white arrow represents the direction of magnetization of the first ferromagnetic part. In FIG. 15, reference numerals 400 </ b> A and 400 </ b> B indicate two adjacent magnetic field generators in the plurality of magnetic field generators 400. As shown in FIG. 15, the two magnetic field generators 400A and 400B are different from each other in the magnetization direction of the first ferromagnetic body part. In the present embodiment, in particular, the direction of magnetization of the first ferromagnetic part of the magnetic field generating part 400A is the direction from the outer peripheral part 300a toward the inner peripheral part 300b. The direction of magnetization of the first ferromagnetic part of the magnetic field generating part 400B is the direction from the inner peripheral part 300b toward the outer peripheral part 300a.

  Here, the direction of magnetization from the outer peripheral portion 300a toward the inner peripheral portion 300b is defined as a first direction, and the direction of magnetization from the inner peripheral portion 300b toward the outer peripheral portion 300a is defined as a second direction. In the present embodiment, the plurality of magnetic field generators 400 are arranged so that the magnetization direction of the first ferromagnetic body portion is alternately switched between the first direction and the second direction.

  When the relative positional relationship between the scale 2 and the magnetic sensor 4 changes, the magnetic sensor 4 is applied to the magnetic sensor 4 based on a magnetic field to be detected by the magnetic sensor 4, that is, a part of a plurality of external magnetic fields generated by the plurality of magnetic field generators 400. The direction of the applied magnetic field changes. In the example shown in FIG. 15, the direction of the magnetic field to be detected rotates around the position where the magnetic sensor 4 is arranged in a plane orthogonal to the central axis C. In particular, in the example shown in FIG. 15, when the scale 2 rotates once, the direction of the magnetic field to be detected changes six rotations, that is, six cycles.

  The configuration of the magnetic sensor 4 in the present embodiment is the same as the example shown in FIGS. 10 and 11 in the first embodiment. In the present embodiment, in the magnetic sensor 4, the Z direction shown in FIGS. 10 to 12 is parallel or substantially parallel to a straight line drawn perpendicularly to the central axis C from the position where the magnetic sensor 4 is disposed. The X direction shown in FIGS. 10 to 12 is arranged in a position facing the outer peripheral portion 300a in a posture that is parallel or substantially parallel to a plane orthogonal to the central axis C.

  Other configurations, operations, and effects in the present embodiment are the same as those in the first embodiment.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 16 is a perspective view showing a schematic configuration of the magnetic sensor system in the present embodiment. The magnetic sensor system in the present embodiment includes a scale 1 that is a linear scale and a magnetic sensor 5 according to the present embodiment. The positional relationship between the scale 1 and the magnetic sensor 5 and the relative operation of the scale 1 with respect to the magnetic sensor 5 are the positional relationship between the scale 1 and the magnetic sensor 4 in the first embodiment and the scale 1 with respect to the magnetic sensor 4. Similar to relative operation.

  In the present embodiment, the scale 1 is configured by a magnetic field generator 500. The magnetic field generator 500 includes a plurality of magnetic field generators 600 that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. In the present embodiment, the plurality of magnetic field generators 600 are arranged in a line. The configuration of the plurality of magnetic field generation units 600 may be the same as the configuration of the plurality of magnetic field generation units 200 in the first embodiment. Or each of the some magnetic field generation | occurrence | production part 600 may be comprised with the permanent magnet. The magnetization directions of the plurality of magnetic field generators 600 are set so as to be switched alternately.

  Next, the magnetic sensor 5 according to the present embodiment will be described with reference to FIGS. FIG. 17 is a circuit diagram of the magnetic sensor 5. FIG. 18 is a cross-sectional view showing a part of the magnetic sensor 5. The magnetic sensor 5 includes a plurality of magnetic detection elements that detect a magnetic field to be detected, and a bias magnetic field generator 8 that generates a plurality of bias magnetic fields applied to the plurality of magnetic detection elements. In the present embodiment, each of the plurality of magnetic detection elements is an MR element.

  The bias magnetic field generator 8 is constituted by the magnetic field generator 9 according to the present embodiment. The magnetic field generator 9 includes a plurality of magnetic field generators that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. The configuration of each of the plurality of magnetic field generation units in the present embodiment is basically the same as the configuration of each of the plurality of magnetic field generation units 200 in the first embodiment. That is, each of the plurality of magnetic field generators in the present embodiment includes at least a first ferromagnetic part and a first antiferromagnetic part. Hereinafter, also in the present embodiment, the first ferromagnetic part is denoted by reference numeral 220 and the first antiferromagnetic part is denoted by reference numeral 210, as in the first embodiment. Each of the plurality of bias magnetic fields is caused by the magnetization of the first ferromagnetic body 220 in at least one magnetic field generator of the plurality of magnetic field generators.

  Particularly in the present embodiment, the plurality of MR elements of the magnetic sensor 5 include two MR elements 101 and 102 connected in series and two MR elements 111 and 112 connected in series. The MR elements 101 and 111 both correspond to the first magnetic detection element in the present invention. Both MR elements 102 and 112 correspond to the second magnetic detection element in the present invention.

  In the present embodiment, the plurality of magnetic field generators of the magnetic field generator 9 include two first magnetic field generators 201 and 211 and two second magnetic field generators 202 and 212. .

  As shown in FIG. 18, the magnetic sensor 5 further includes a substrate 51, two upper electrodes 33, 34, and three lower electrodes 43, 44, 45. The lower electrodes 43, 44, 45 are arranged in a row on the substrate 51 with a space between each other. The MR element 101 is disposed on the lower electrode 43 in the vicinity of the end closest to the lower electrode 44. The MR element 102 is disposed on the lower electrode 44 near the end closest to the lower electrode 43. The MR element 111 is disposed on the lower electrode 44 in the vicinity of the end closest to the lower electrode 45. The MR element 112 is disposed on the vicinity of the end portion of the lower electrode 45 closest to the lower electrode 44. The magnetic field generators 201, 202, 211, and 212 are disposed on the MR elements 101, 102, 111, and 112, respectively. The upper electrode 33 is disposed on the magnetic field generators 201 and 202. The upper electrode 34 is disposed on the magnetic field generators 211 and 212.

  The magnetic sensor 5 further includes insulating layers 52 and 53 and a protective film 54. The insulating layer 52 is disposed around the lower electrodes 43, 44 and 45 on the substrate 51. The insulating layer 53 is disposed around the MR elements 101, 102, 111, 112 and the magnetic field generators 201, 202, 211, 212 on the lower electrodes 43, 44, 45 and the insulating layer 52. The protective film 54 is disposed so as to cover the upper electrodes 33 and 34 and the insulating layer 53.

  The magnetic sensor 5 includes a half bridge circuit. The half bridge circuit includes a first magnetic detection element array R1 and a second magnetic detection element array R2 connected in series. As shown in FIG. 17, the first magnetic detection element array R <b> 1 is composed of MR elements 101 and 102. The second magnetic detection element array R2 includes MR elements 111 and 112. The magnetic sensor 5 further includes a power supply port V, a ground port G, and an output port E. One end of the first magnetic detection element array R1 is connected to the power supply port V. The other end of the first magnetic detection element array R1 is connected to the output port E. One end of the second magnetic detection element array R2 is connected to the output port E. The other end of the second magnetic detection element array R2 is connected to the ground port G.

  A power supply voltage having a predetermined magnitude is applied to the power supply port V. The ground port G is connected to the ground. The resistance values of the MR elements 101, 102, 111, and 112 change according to the magnetic field to be detected. The resistance values of the MR elements 101 and 102 change with the same phase. The resistance values of the MR elements 111 and 112 change at a phase different from the resistance values of the MR elements 101 and 102 by 180 °. The output port E outputs a detection signal corresponding to the potential at the connection point between the first magnetic detection element array R1 and the second magnetic detection element array R2, that is, the connection point between the MR element 102 and the MR element 111. The detection signal changes according to the magnetic field to be detected. The output signal of the magnetic sensor 5 is generated by performing a predetermined calculation using the detection signal. For example, the output signal of the magnetic sensor 5 is generated by adding a predetermined offset voltage to the detection signal. The output signal of the magnetic sensor 5 changes according to the magnetic field to be detected.

  Next, an example of the configuration of each of the MR elements 101, 102, 111, and 112 and an example of the configuration of each of the magnetic field generation units 201, 202, 211, and 212 will be described with reference to FIG. FIG. 19 is a side view showing an example of the configuration of the MR element and the magnetic field generator. In the following description, an arbitrary MR element, a magnetic field generation unit, an upper electrode, and a lower electrode are denoted by reference numerals 10, 20, 30, and 40, respectively.

  The configuration of the MR element 10 is the same as that of the first embodiment. That is, the MR element 10 has at least a magnetization fixed layer 13, a free layer 15, and a nonmagnetic layer 14. In the example shown in FIG. 19, the MR element 10 further includes a base layer 11, an antiferromagnetic layer 12, and a protective layer 16. In this example, the underlayer 11, the antiferromagnetic layer 12, the magnetization fixed layer 13, the nonmagnetic layer 14, the free layer 15 and the protective layer 16 are laminated in this order from the lower electrode 40 side along the Z direction. .

  The magnetic field generator 20 includes at least a first ferromagnetic part 220 and a first antiferromagnetic part 210. In the example shown in FIG. 19, the first antiferromagnetic portion 210 and the first ferromagnetic portion 220 are laminated in this order from the MR element 10 side along the Z direction. FIG. 19 shows an example in which the magnetic field generation unit 20 has the configuration of the first example of the magnetic field generation unit 200 described in the first embodiment. However, the magnetic field generation unit 20 may have any of the configurations of the second to eighth examples of the magnetic field generation unit 200 described in the first embodiment.

  Next, with reference to FIG. 17, the direction of magnetization of the magnetization fixed layer 13 of each of the MR elements 101, 102, 111, and 112 will be described. In FIG. 17, solid arrows in the MR elements 101, 102, 111, 112 represent the magnetization direction of the magnetization fixed layer 13 in the MR elements 101, 102, 111, 112. Here, as shown in FIG. 17, the third and fourth directions D3 and D4 are defined. The definitions of the third and fourth directions D3 and D4 are the same as those in the first embodiment. In FIG. 17, the third direction D3 is a direction toward the right side. The fourth direction D4 is a direction opposite to the third direction D3.

  As shown in FIG. 17, the magnetization direction of the magnetization fixed layer 13 in each of the MR elements 101 and 102 is the third direction D3, and the magnetization direction of the magnetization fixed layer 13 in each of the MR elements 111 and 112 Is the fourth direction D4. In this case, the potential at the connection point of the MR elements 102 and 111 changes according to the strength of the magnetic field component to be detected in the direction parallel to the third and fourth directions D3 and D4, that is, in the X direction. The output port E outputs a detection signal corresponding to the potential at the connection point of the MR elements 102 and 111. The detection signal represents the intensity of the magnetic field component to be detected in the X direction.

  Note that the magnetization direction of the magnetization fixed layer 13 in the MR elements 101, 102, 111, and 112 may be slightly deviated from the above-mentioned direction from the viewpoint of the accuracy of manufacturing the MR element.

  Next, referring to FIG. 17, the direction of magnetization of first ferromagnetic body portion 220 of each of magnetic field generation portions 201, 202, 211, 212 and the MR element 101, 102, 111, 112 are applied. The bias magnetic field will be described. In FIG. 17, two-dot chain arrows in the magnetic field generation units 201, 202, 211, and 212 indicate the magnetization direction of the first ferromagnetic body 220 in the magnetic field generation units 201, 202, 211, and 212. .

  Here, as shown in FIG. 17, a fifth direction D5 and a sixth direction D6 are defined. In the present embodiment, the fifth and sixth directions D5 and D6 are each a specific direction parallel to the Y direction. In FIG. 17, the fifth direction D5 is a direction toward the upper side. The sixth direction D6 is a direction opposite to the fifth direction D5. Particularly in the present embodiment, the magnetization direction of the first ferromagnetic body 220 in the magnetic field generators 201 and 211 is the fifth direction D5. The direction of magnetization of the first ferromagnetic body 220 in the magnetic field generators 202 and 212 is a sixth direction D6.

  The magnetic sensor 5 includes one set of first and second magnetic field generation unit aggregates provided corresponding to one half-bridge circuit. The first magnetic field generation unit assembly includes magnetic field generation units 201 and 202, and generates two bias magnetic fields applied to the MR elements 101 and 102 constituting the first magnetic detection element array R1. The second magnetic field generation unit aggregate includes magnetic field generation units 211 and 212, and generates two bias magnetic fields applied to the MR elements 111 and 112 constituting the second magnetic detection element array R2.

  The bias magnetic field applied to the MR element 101 is caused by the magnetization of the first ferromagnetic body 220 of the magnetic field generator 201. The bias magnetic field applied to the MR element 102 is caused by the magnetization of the first ferromagnetic body 220 of the magnetic field generator 202. The direction of the main component of the bias magnetic field at the position of the MR element 101 is the direction opposite to the magnetization direction of the first ferromagnetic body 220 of the magnetic field generator 201, that is, the sixth direction D6. The direction of the main component of the bias magnetic field at the position of the MR element 102 is the direction opposite to the magnetization direction of the first ferromagnetic body 220 of the magnetic field generator 202, that is, the fifth direction D5.

  The magnetization direction (fifth direction D5) of the first ferromagnetic body portion 220 of the magnetic field generation unit 201 intersects the magnetization direction (third direction D3) of the magnetization fixed layer 13 of the MR element 101. The magnetization direction (sixth direction D6) of the first ferromagnetic body 220 of the magnetic field generation unit 202 intersects with the magnetization direction (third direction D3) of the magnetization fixed layer 13 of the MR element 102.

  The bias magnetic field applied to the MR element 111 is caused by the magnetization of the first ferromagnetic body 220 of the magnetic field generator 211. The bias magnetic field applied to the MR element 112 is caused by the magnetization of the first ferromagnetic body 220 of the magnetic field generator 212. The direction of the main component of the bias magnetic field at the position of the MR element 111 is the direction opposite to the magnetization direction of the first ferromagnetic body 220 of the magnetic field generator 211, that is, the sixth direction D6. The direction of the main component of the bias magnetic field at the position of the MR element 112 is the direction opposite to the magnetization direction of the first ferromagnetic body 220 of the magnetic field generator 212, that is, the fifth direction D5.

  The magnetization direction (fifth direction D5) of the first ferromagnetic body 220 of the magnetic field generator 211 intersects with the magnetization direction (fourth direction D4) of the magnetization fixed layer 13 of the MR element 111. The magnetization direction (sixth direction D6) of the first ferromagnetic body unit 220 of the magnetic field generation unit 212 intersects the magnetization direction (fourth direction D4) of the magnetization fixed layer 13 of the MR element 112.

  When the intensity of the magnetic field component to be detected in the direction parallel to the magnetization direction (X direction) of the magnetization fixed layer 13 becomes 0, the bias magnetic field makes the free layer 15 a single domain and Used to direct the direction of magnetization in a certain direction.

  In the present embodiment, the magnetic field generation units 201 and 202 constituting the first magnetic field generation unit aggregate are different in the magnetization direction of the first ferromagnetic body unit 220. In the present embodiment, in particular, the magnetic field generation is performed so that the direction of the main component of the bias magnetic field applied to the MR element 101 and the direction of the main component of the bias magnetic field applied to the MR element 102 are opposite to each other. Units 201 and 202 are configured. As a result, according to the present embodiment, in the first magnetic detection element array R1, the influence of the bias magnetic field on the sensitivity of the MR element 101 and the influence of the bias magnetic field on the sensitivity of the MR element 102 are offset. can do. As a result, according to the present embodiment, it is possible to prevent the characteristics of the first magnetic detection element array R1 from differing from the desired characteristics due to the bias magnetic field.

  Similarly, in the present embodiment, the magnetic field generation units 211 and 212 that constitute the second magnetic field generation unit aggregate are different from each other in the magnetization direction of the first ferromagnetic body unit 220. Particularly in the present embodiment, in this embodiment, the direction of the main component of the bias magnetic field applied to the MR element 111 and the direction of the main component of the bias magnetic field applied to the MR element 112 are opposite to each other. Thus, the magnetic field generation units 211 and 212 are configured. Thus, according to the present embodiment, in the second magnetic detection element array R2, the influence of the bias magnetic field on the sensitivity of the MR element 111 and the influence of the bias magnetic field on the sensitivity of the MR element 112 are offset. can do. As a result, according to the present embodiment, it is possible to prevent the characteristics of the second magnetic detection element array R2 from differing from the desired characteristics due to the bias magnetic field.

  The magnetic field generator 9 according to the present embodiment can be manufactured by the same method as the magnetic field generator 100 according to the first embodiment. As described in the first embodiment, the magnetization of the first ferromagnetic portion 220 of each of the two adjacent magnetic field generators can be achieved without increasing the distance between the two adjacent magnetic field generators. It is easy to set the direction. According to the present embodiment, the magnetic field generators 201, 202, 211, and 212 are arranged in a desired pattern, and the magnetic field generator 9 having high resistance to a disturbance magnetic field, and the magnetic sensor 5 including the magnetic field generator 9 are provided. Can be realized. In addition, according to the present embodiment, by reducing the distance between two adjacent magnetic field generation units, the degree of freedom of arrangement of the magnetic field generation units 201, 202, 211, and 212 can be improved, or the magnetic field generation unit The occupied area of 201, 202, 211, 212 can be reduced.

[Modification]
Next, a modification of the magnetic sensor system in the present embodiment will be described with reference to FIG. FIG. 20 is a perspective view showing a schematic configuration of a modified example of the magnetic sensor system in the present embodiment. In a modification, the magnetic sensor system includes a scale 2 that is an annular rotary scale instead of the scale 1 shown in FIG. The positional relationship between the scale 2 and the magnetic sensor 5 and the relative operation of the scale 2 with respect to the magnetic sensor 5 are the same as the positional relationship between the scale 2 and the magnetic sensor 4 and the scale 2 with respect to the magnetic sensor 4 in the second embodiment. This is the same as the relative operation.

  The scale 2 is constituted by a magnetic field generator 700. The magnetic field generator 700 includes a plurality of magnetic field generators 800 that are arranged in a predetermined pattern and generate a plurality of external magnetic fields. In the modification, the plurality of magnetic field generators 800 are arranged in an annular shape so as to form an aggregate having an outer peripheral part and an inner peripheral part, like the plurality of magnetic field generators 400 in the second embodiment. Yes. In the example illustrated in FIG. 20, the number of the plurality of magnetic field generation units 800 is six. The internal configuration of each of the plurality of magnetic field generation units 800 is the same as the internal configuration of each of the plurality of magnetic field generation units 600 illustrated in FIG.

  Other configurations, operations, and effects in the present embodiment are the same as those in the first or second embodiment.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIGS. FIG. 21 is a circuit diagram showing the magnetic sensor according to the present embodiment. FIG. 22 is a cross-sectional view showing the magnetic sensor according to the present embodiment. The magnetic sensor 5 according to the present embodiment is different from the third embodiment in the following points. In the magnetic sensor 5 according to the present embodiment, two first magnetic field generators 201 and 211 and two second magnetic fields are included in the plurality of magnetic field generators of the bias magnetic field generator 8 (magnetic field generator 9). The generators 202 and 212, two third magnetic field generators 203 and 213, and two fourth magnetic field generators 204 and 214 are included.

  As shown in FIG. 22, the magnetic field generators 201 and 202 are embedded in the insulating layer 53. As shown in FIGS. 21 and 22, the magnetic field generation unit 201 and the magnetic field generation unit 202 are arranged at a predetermined interval along the Y direction so that the MR element 101 is interposed therebetween. Yes. Similarly, the magnetic field generators 203, 204, 211 to 214 are embedded in the insulating layer 53. The magnetic field generation unit 203 and the magnetic field generation unit 204 are arranged at a predetermined interval along the Y direction so that the MR element 102 is interposed therebetween. The magnetic field generator 211 and the magnetic field generator 212 are arranged at a predetermined interval along the Y direction so that the MR element 111 is interposed therebetween. The magnetic field generator 213 and the magnetic field generator 214 are arranged at a predetermined interval along the Y direction so that the MR element 112 is interposed therebetween.

  As shown in FIG. 21, the magnetic field generation unit 201 and the magnetic field generation unit 203 are adjacent to each other in the X direction. The magnetic field generator 202 and the magnetic field generator 204 are adjacent to each other in the X direction. The magnetic field generator 211 and the magnetic field generator 213 are adjacent to each other in the X direction. The magnetic field generator 212 and the magnetic field generator 214 are adjacent to each other in the X direction.

  In the present embodiment, the upper electrode 33 is disposed on the MR elements 101 and 102. The upper electrode 34 (see FIG. 18) is disposed on the MR elements 111 and 112.

  Next, an example of the configuration of each of the magnetic field generators 201 to 204 and 211 to 214 will be described with reference to FIG. As shown in FIG. 22, each of the magnetic field generators 201 and 202 includes at least a first ferromagnetic part 220 and a first antiferromagnetic part 210. In the example shown in FIG. 22, the first antiferromagnetic part 210 and the first ferromagnetic part 220 are stacked along the Z direction. FIG. 22 shows an example in which each of the magnetic field generation units 201 and 202 has the configuration of the first example of the magnetic field generation unit 200 described in the first embodiment. However, each of the magnetic field generation units 201 and 202 may be configured in any one of the second to eighth examples of the magnetic field generation unit 200 described in the first embodiment.

  Although not shown, the configuration of each of the magnetic field generators 203, 204, 211 to 214 is the same as the configuration of each of the magnetic field generators 201, 202. The above description of the magnetic field generators 201 and 202 also applies to the magnetic field generators 203, 204, 211 to 214.

  Next, referring to FIG. 21, the direction of magnetization of first ferromagnetic body 220 of each of magnetic field generators 201-204, 211-214 and the MR element 101, 102, 111, 112 are applied. The bias magnetic field will be described. In FIG. 21, white arrows in the magnetic field generation units 201 to 204 and 211 to 214 represent the magnetization directions of the first ferromagnetic body 220 in the magnetic field generation units 201 to 204 and 211 to 214.

  Here, as shown in FIG. 21, fifth and sixth directions D5 and D6 are defined. The definitions of the fifth and sixth directions D5 and D6 are the same as in the third embodiment. In FIG. 21, the fifth direction D5 is a direction toward the upper side. The sixth direction D6 is a direction opposite to the fifth direction D5. The direction of magnetization of the first ferromagnetic body 220 in the magnetic field generators 201, 202, 211, 212 is the fifth direction D5. The magnetization direction of the first ferromagnetic body 220 in the magnetic field generators 203, 204, 213, and 214 is a sixth direction D6.

  Similar to the third embodiment, also in this embodiment, the magnetic sensor 5 has one set of first and second magnetic field generation unit aggregates provided corresponding to one half-bridge circuit. Contains. In the present embodiment, the first magnetic field generation unit aggregate includes a pair of first to fourth magnetic field generation units 201 to 204, and MR elements 101 and 102 constituting the first magnetic detection element row R1. The two bias magnetic fields applied to are generated. The second magnetic field generation unit assembly includes another set of first to fourth magnetic field generation units 211 to 214, and is applied to the MR elements 111 and 112 constituting the second magnetic detection element array R2. Two bias magnetic fields are generated.

  The bias magnetic field applied to the MR element 101 is caused by the magnetization of the first ferromagnetic member 220 of the magnetic field generator 201 and the magnetization of the first ferromagnetic member 220 of the magnetic field generator 202. The bias magnetic field applied to the MR element 102 is caused by the magnetization of the first ferromagnetic member 220 of the magnetic field generator 203 and the magnetization of the first ferromagnetic member 220 of the magnetic field generator 204. The direction of the main component of the bias magnetic field at the position of the MR element 101 is the same direction as the magnetization direction (fifth direction D5) of the first ferromagnetic body 220 of each of the magnetic field generators 201 and 202. The direction of the main component of the bias magnetic field at the position of the MR element 102 is the same direction as the magnetization direction (sixth direction D6) of the first ferromagnetic body 220 of each of the magnetic field generation units 203 and 204.

  The magnetization direction of the magnetization fixed layer 13 of each of the MR elements 101 and 102 is the same as that in the third embodiment. Here, as shown in FIG. 21, the third and fourth directions D3 and D4 are defined. The definitions of the directions of the third and fourth directions D3 and D4 are the same as those of the third embodiment. In FIG. 21, the third direction D3 is a direction toward the right side. The fourth direction D4 is a direction opposite to the third direction D3. As shown in FIG. 21, the magnetization direction of the magnetization fixed layer 13 in each of the MR elements 101 and 102 is the third direction D3. The magnetization direction (fifth direction D5) of the first ferromagnetic body 220 of each of the magnetic field generation units 201 and 202 is the same as the magnetization direction (third direction D3) of the magnetization fixed layer 13 of the MR element 101. Intersect. The magnetization direction (sixth direction D6) of the first ferromagnetic body 220 of each of the magnetic field generation units 203 and 204 is the same as the magnetization direction (third direction D3) of the magnetization fixed layer 13 of the MR element 102. Intersect.

  The bias magnetic field applied to the MR element 111 is due to the magnetization of the first ferromagnetic body 220 of the magnetic field generator 211 and the magnetization of the first ferromagnetic body 220 of the magnetic field generator 212. The bias magnetic field applied to the MR element 112 is due to the magnetization of the first ferromagnetic member 220 of the magnetic field generator 213 and the magnetization of the first ferromagnetic member 220 of the magnetic field generator 214. The direction of the main component of the bias magnetic field at the position of the MR element 111 is the same as the magnetization direction (fifth direction D5) of the first ferromagnetic body 220 of each of the magnetic field generators 211 and 212. The direction of the main component of the bias magnetic field at the position of the MR element 112 is the same direction as the magnetization direction (sixth direction D6) of the first ferromagnetic body 220 of each of the magnetic field generation units 213 and 214.

  The magnetization direction of the magnetization fixed layer 13 of each of the MR elements 111 and 112 is the same as that in the third embodiment. As shown in FIG. 21, the magnetization direction of the magnetization fixed layer 13 in each of the MR elements 111 and 112 is the fourth direction D4. The magnetization direction (fifth direction D5) of the first ferromagnetic body portion 220 of each of the magnetic field generation units 211 and 212 is the same as the magnetization direction (fourth direction D4) of the magnetization fixed layer 13 of the MR element 111. Intersect. The magnetization direction (sixth direction D6) of the first ferromagnetic body 220 of each of the magnetic field generation units 213 and 214 is the same as the magnetization direction (fourth direction D4) of the magnetization fixed layer 13 of the MR element 112. Intersect.

  In the present embodiment, the magnetic field generators 201 and 203 are adjacent to each other and have different magnetization directions from each other. The magnetic field generators 202 and 204 are adjacent to each other and have different magnetization directions from each other. In the present embodiment, in particular, the magnetic field generation is performed so that the direction of the main component of the bias magnetic field applied to the MR element 101 and the direction of the main component of the bias magnetic field applied to the MR element 102 are opposite to each other. Units 201 to 204 are configured. As a result, according to the present embodiment, in the first magnetic detection element array R1, the influence of the bias magnetic field on the sensitivity of the MR element 101 and the influence of the bias magnetic field on the sensitivity of the MR element 102 are offset. can do. As a result, according to the present embodiment, it is possible to prevent the characteristics of the first magnetic detection element array R1 from differing from the desired characteristics due to the bias magnetic field.

  Similarly, in the present embodiment, the magnetic field generators 211 and 213 are adjacent to each other and have different magnetization directions from each other. The magnetic field generators 212 and 214 are adjacent to each other and have different magnetization directions from the first ferromagnetic body 220. Particularly in the present embodiment, the magnetic field generation is performed so that the direction of the main component of the bias magnetic field applied to the MR element 111 and the direction of the main component of the bias magnetic field applied to the MR element 112 are opposite to each other. Portions 211 to 214 are configured. Thus, according to the present embodiment, in the second magnetic detection element array R2, the influence of the bias magnetic field on the sensitivity of the MR element 111 and the influence of the bias magnetic field on the sensitivity of the MR element 112 are offset. can do. As a result, according to the present embodiment, it is possible to prevent the characteristics of the second magnetic detection element array R2 from differing from the desired characteristics due to the bias magnetic field.

  The magnetic field generator 9 according to the present embodiment can be manufactured by the same method as the magnetic field generator 100 according to the first embodiment. As described in the first embodiment, the magnetization of the first ferromagnetic portion 220 of each of the two adjacent magnetic field generators can be achieved without increasing the distance between the two adjacent magnetic field generators. It is easy to set the direction. According to the present embodiment, the magnetic field generators 201 to 204, 211 to 214 are arranged in a desired pattern, and the magnetic field generator 9 having high resistance to a disturbance magnetic field, and the magnetic sensor 5 including the magnetic field generator 9 are provided. Can be realized. In addition, according to the present embodiment, by reducing the distance between two adjacent magnetic field generation units, the degree of freedom of arrangement of the magnetic field generation units 201 to 204 and 211 to 214 can be improved, or the magnetic field generation unit The occupation area of 201-204 and 211-214 can be reduced.

  In addition, the magnetic sensor system in this Embodiment may be provided with the scale 1 shown in FIG. 16 in 3rd Embodiment, and is provided with the scale 2 shown in FIG. 20 in 3rd Embodiment. It may be. Other configurations, operations, and effects in the present embodiment are the same as those in the third embodiment.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 23 is a circuit diagram showing the magnetic sensor according to the present embodiment. The magnetic sensor 5 according to the present embodiment is different from the fourth embodiment in the following points. As shown in FIG. 23, in the present embodiment, the magnetization directions of the first ferromagnetic body 220 in the magnetic field generators 201 to 204 and 211 to 214 are both in the X direction and the Y direction. It is a direction inclined with respect to it.

  Here, with reference to the sixth direction D6 shown in FIG. 23, the seventh and eighth directions are defined as follows. The sixth direction D6 is the direction defined in the fourth embodiment. In FIG. 23, the sixth direction D6 is a downward direction. The seventh direction is a direction rotated from the direction of the sixth direction D6 by the first angle in the clockwise direction. The eighth direction is a direction rotated counterclockwise by the second angle from the direction of the sixth direction D6. The first and second angles are angles within a range greater than 0 ° and less than 90 °. In FIG. 23, the seventh direction is a direction toward the lower left side, and the eighth direction is a direction toward the lower right side. The magnetization direction of the first ferromagnetic body 220 in the magnetic field generators 201, 202, 211, and 212 is the seventh direction. The direction of magnetization of the first ferromagnetic body 220 in the magnetic field generators 203, 204, 213, and 214 is the eighth direction. The first angle and the second angle are preferably equal.

  In the present embodiment, the bias magnetic fields applied to the MR elements 101 and 102 are all due to the four first ferromagnetic parts 220 in the magnetic field generators 201 to 204. In FIG. 23, two-dot chain arrows in the vicinity of the MR elements 101 and 102 indicate the directions of the main components of the bias magnetic field at the respective positions of the MR elements 101 and 102. In the present embodiment, in particular, the direction of magnetization of the four first ferromagnetic parts 220 in the magnetic field generators 201 to 204 is sixth in the direction of the main component of the bias magnetic field at each position of the MR elements 101 and 102. The direction D6 is set.

  The bias magnetic field applied to the MR elements 111 and 112 is due to the four first ferromagnetic parts 220 in the magnetic field generators 211 to 214. In FIG. 23, two-dot chain arrows in the vicinity of the MR elements 111 and 112 indicate the directions of the main components of the bias magnetic field at the positions of the MR elements 111 and 112, respectively. Particularly in the present embodiment, the direction of magnetization of the four first ferromagnetic parts 220 in the magnetic field generation parts 211 to 214 is the sixth direction of the main component of the bias magnetic field at each position of the MR elements 111 and 112. The direction D6 is set.

  In general, the sensitivity of the MR element and the range of the intensity of the magnetic field to be detected by the MR element are in a trade-off relationship, and these are adjusted according to requirements. The range of the sensitivity of the MR element and the intensity of the magnetic field to be detected can be adjusted by the magnitude of the bias magnetic field applied to the MR element. In the present embodiment, the magnitude of the bias magnetic field applied to the MR elements 101, 102, 111, 112 can be easily adjusted by adjusting the first and second angles, for example. Thereby, according to the present embodiment, the sensitivity of the MR elements 101, 102, 111, 112 and the range of the intensity of the magnetic field to be detected by the MR elements 101, 102, 111, 112 can be easily adjusted. Is possible.

  Other configurations, operations, and effects in the present embodiment are the same as those in the fourth embodiment.

[Sixth Embodiment]
Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 24 is a circuit diagram showing a circuit configuration of the magnetic sensor system in the present embodiment. The magnetic sensor system in the present embodiment includes the first magnetic sensor 5A and the second magnetic sensor 5B according to the present embodiment, and detects the direction and magnitude of the magnetic field to be detected. In the present embodiment, the detection target magnetic field is a magnetic field generated by, for example, geomagnetism or an arbitrary magnet.

  The configuration of each of the first and second magnetic sensors 5A and 5B is the same as the configuration of the magnetic sensor 5 according to the fourth embodiment. In the first magnetic sensor 5A, the arrangement of the MR elements 101, 102, 111, 112 and the magnetic field generators 201-204, 211-214, and the magnetization of the magnetization fixed layer 13 of each of the MR elements 101, 102, 111, 112 are shown. The direction, the direction of magnetization of the first ferromagnetic body 220 of each of the magnetic field generators 201 to 204, 211 to 214, and the direction of the bias magnetic field applied to the MR elements 101, 102, 111, and 112 are This is the same as the fourth embodiment.

  MR elements 101, 102, 111, 112 and magnetic field generators 201-204, 211-214 in second magnetic sensor 5B are MR elements 101, 102, 111, 112 and magnetic field generator 201 in first magnetic sensor 5A. ˜204, 211 to 214 are arranged in such a posture as to be rotated by 90 ° counterclockwise in the XY plane. Accordingly, the magnetization direction of each magnetization fixed layer 13 of the MR elements 101, 102, 111, 112 in the second magnetic sensor 5B is the same as that of each of the MR elements 101, 102, 111, 112 in the first magnetic sensor 5A. The magnetization direction of the magnetization fixed layer 13 is a direction rotated by 90 ° counterclockwise in the XY plane. Similarly, the magnetization direction of the first ferromagnetic body 220 of each of the magnetic field generators 201 to 204 and 211 to 214 in the second magnetic sensor 5B is the same as that of the magnetic field generators 201 to 204 in the first magnetic sensor 5A. , 211 to 214, the magnetization directions of the first ferromagnetic portions 220 are rotated in the counterclockwise direction by 90 ° in the XY plane. Therefore, the direction of the bias magnetic field applied to the MR elements 101, 102, 111, 112 in the second magnetic sensor 5B is the bias magnetic field applied to the MR elements 101, 102, 111, 112 in the first magnetic sensor 5A. Is the direction rotated by 90 ° counterclockwise in the XY plane.

  The output port E of the first magnetic sensor 5A outputs a first detection signal corresponding to the potential at the connection point between the MR element 102 and the MR element 111 in the first magnetic sensor 5A. In the first magnetic sensor 5A, the potential at the connection point of the MR elements 102 and 111 changes according to the strength of the magnetic field component to be detected in the X direction. The first detection signal represents the intensity of the magnetic field component to be detected in the X direction.

  The output port E of the second magnetic sensor 5B outputs a second detection signal corresponding to the potential at the connection point between the MR element 102 and the MR element 111 in the second magnetic sensor 5B. In the second magnetic sensor 5B, the potential at the connection point of the MR elements 102 and 111 changes according to the strength of the magnetic field component to be detected in the Y direction. The second detection signal represents the intensity of the magnetic field component to be detected in the Y direction.

  The magnetic sensor system in the present embodiment further includes a calculation unit 7. The computing unit 7 has two input ends and one output end. The two input ends of the calculation unit 7 are connected to the output ports E of the first and second magnetic sensors 5A and 5B, respectively. The computing unit 7 calculates an output signal representing the direction and magnitude of the magnetic field to be detected based on the first and second detection signals. The computing unit 7 can be realized by a microcomputer, for example.

  The first and second magnetic sensors 5A and 5B are magnetic field generators according to the third embodiment, instead of the bias magnetic field generators configured by the magnetic field generator 9 according to the fourth embodiment. 9 may be provided. Other configurations, operations, and effects in the present embodiment are the same as those in the third or fourth embodiment.

[Seventh Embodiment]
Next, a seventh embodiment of the present invention will be described with reference to FIG. FIG. 25 is a circuit diagram showing a circuit configuration of the magnetic sensor system in the present embodiment. The magnetic sensor system according to the present embodiment is different from the sixth embodiment in the following points. The magnetic sensor system in the present embodiment includes a first magnetic sensor 6A and a second magnetic sensor 6B instead of the first and second magnetic sensors 5A and 5B in the sixth embodiment. Each of the first and second magnetic sensors 6A and 6B includes a plurality of MR elements, similarly to the first and second magnetic sensors 5A and 5B.

  The plurality of MR elements of the first magnetic sensor 6A include two MR elements 101 and 102 connected in series, two MR elements 111 and 112 connected in series, and two MR elements connected in series. Elements 103 and 104 and two MR elements 113 and 114 connected in series are included. The MR elements 101, 103, 111, and 113 all correspond to the first magnetic detection element in the present invention. The MR elements 102, 104, 112, and 114 all correspond to the second magnetic detection element in the present invention. The configuration of each of the MR elements 101 to 104, 111 to 114 is the same as that of the MR element 10 in the first embodiment.

  Further, the first magnetic sensor 6A includes a bias magnetic field generator configured by a magnetic field generator including a plurality of magnetic field generators. The plurality of magnetic field generators of the first magnetic sensor 6A include four first magnetic field generators 201, 205, 211, 215, four second magnetic field generators 202, 206, 212, 216, 4 Three third magnetic field generators 203, 207, 213, and 217 and four fourth magnetic field generators 204, 208, 214, and 218 are included. The configuration of the magnetic field generators 201 to 204 and 211 to 214 is the same as that of the magnetic field generators 201 to 204 and 211 to 214 in the sixth embodiment. Similarly, the configuration of the magnetic field generation units 205 to 208 and 215 to 218 is the same as that of the magnetic field generation units 201 to 204 and 211 to 214 in the sixth embodiment.

  The first magnetic sensor 6A includes a first region where the MR elements 101, 102, 111, 112 and the magnetic field generators 201-204, 211-214 are arranged, the MR elements 103, 104, 113, 114, and the magnetic field generation. 2nd area | region where the parts 205-208 and 215-218 are arrange | positioned. In the example shown in FIG. 25, the first region and the second region are at different positions in the Y direction.

  The arrangement of the MR elements 101, 102, 111, 112 and the magnetic field generators 201-204, 211-214 is the MR elements 101, 102, 111, 112 in the first magnetic sensor 5A described in the sixth embodiment. This is the same as the arrangement of the magnetic field generators 201 to 204 and 211 to 214. MR elements 103, 104, 113, 114 and magnetic field generators 205-208, 215-218 are arranged at different positions in the Y direction, except for MR elements 101, 102, 111, 112 and magnetic field generator 201. ˜204, 211˜214 are the same.

  The direction of magnetization of the magnetization fixed layer 13 of each of the MR elements 101, 102, 111, 112, the direction of magnetization of the first ferromagnetic body 220 of each of the magnetic field generators 201-204, 211-214, and MR The direction of the bias magnetic field applied to the elements 101, 102, 111, 112 is the magnetization fixed layer of each of the MR elements 101, 102, 111, 112 in the first magnetic sensor 5A described in the sixth embodiment. 13, the direction of magnetization of the first ferromagnetic body 220 of each of the magnetic field generators 201 to 204, 211 to 214, and the bias magnetic field applied to the MR elements 101, 102, 111, 112. Same as direction.

  The magnetization direction of the magnetization fixed layer 13 of each of the MR elements 103, 104, 113, 114 is opposite to the magnetization direction of the magnetization fixed layer 13 of each of the MR elements 101, 102, 111, 112. The direction of magnetization of the first ferromagnetic body 220 of each of the magnetic field generators 205 to 208, 215 to 218 and the direction of the bias magnetic field applied to the MR elements 103, 104, 113, 114 are as follows. The direction of magnetization of the first ferromagnetic part 220 of each of 201 to 204 and 211 to 214 is the same as the direction of the bias magnetic field applied to the MR elements 101, 102, 111, and 112.

  The first magnetic sensor 6A includes first and second half bridge circuits. The first and second half-bridge circuits include first and second magnetic detection element arrays connected in series, respectively. The first magnetic detection element array of the first half bridge circuit is composed of MR elements 101 and 102. The second magnetic detection element array of the first half bridge circuit is configured by MR elements 111 and 112. The first magnetic detection element row of the second half-bridge circuit is composed of MR elements 103 and 104. The second magnetic detection element array of the second half bridge circuit is configured by MR elements 113 and 114. The MR elements 101 to 104 and 111 to 114 constitute a Wheatstone bridge circuit.

  The first magnetic sensor 6A further includes a power supply port V, a ground port G, a first output port E1, and a second output port E2. In the first half bridge circuit, one end of the first magnetic detection element array is connected to the power supply port V. The other end of the first magnetic detection element array is connected to the first output port E1. One end of the second magnetic detection element array is connected to the first output port E1. The other end of the second magnetic detection element array is connected to the ground port G.

  In the second half bridge circuit, one end of the first magnetic detection element row is connected to the power supply port V. The other end of the first magnetic detection element array is connected to the second output port E2. One end of the second magnetic detection element array is connected to the second output port E2. The other end of the second magnetic detection element array is connected to the ground port G.

  A power supply voltage having a predetermined magnitude is applied to the power supply port V. The ground port G is connected to the ground. The resistance values of the MR elements 101 to 104 and 111 to 114 change according to the magnetic field to be detected. The resistance values of the MR elements 101, 102, 113, 114 change with the same phase. The resistance values of the MR elements 103, 104, 111, and 112 change with a phase that is 180 ° different from the resistance values of the MR elements 101, 102, 113, and 114. The first output port E1 corresponds to the potential at the connection point between the first magnetic detection element row and the second magnetic detection element row in the first half-bridge circuit, that is, the connection point between the MR element 102 and the MR element 111. 1 detection signal is output. The second output port E2 corresponds to the potential at the connection point between the first magnetic detection element array and the second magnetic detection element array in the second half bridge circuit, that is, the connection point between the MR element 104 and the MR element 113. 2 detection signals are output. The first and second detection signals change according to the magnetic field to be detected. The second detection signal is 180 degrees out of phase with the first detection signal.

  The configuration of the second magnetic sensor 6B is the same as the configuration of the first magnetic sensor 6A. However, the MR elements 101 to 104 and 111 to 114 and the magnetic field generation units 201 to 208 and 211 to 218 in the second magnetic sensor 6B are the same as the MR elements 101 to 104 and 111 to 114 and the magnetic field generation in the first magnetic sensor 6A. The parts 201 to 208 and 211 to 218 are arranged in such a posture as to be rotated counterclockwise by 90 ° in the XY plane. Therefore, the magnetization directions of the magnetization fixed layers 13 of the MR elements 101 to 104 and 111 to 114 in the second magnetic sensor 6B are the same as those of the MR elements 101 to 104 and 111 to 114 in the first magnetic sensor 6A. The magnetization direction of the magnetization fixed layer 13 is a direction rotated by 90 ° counterclockwise in the XY plane. Similarly, the direction of magnetization of the first ferromagnetic body 220 of each of the magnetic field generators 201 to 208, 211 to 218 in the second magnetic sensor 6B is the same as that of the magnetic field generators 201 to 208 in the first magnetic sensor 6A. , 211 to 218 are rotated by 90 ° in the counterclockwise direction in the XY plane. Therefore, the direction of the bias magnetic field applied to the MR elements 101 to 104 and 111 to 118 in the second magnetic sensor 6B is the bias magnetic field applied to the MR elements 101 to 104 and 111 to 118 in the first magnetic sensor 6A. Is the direction rotated by 90 ° counterclockwise in the XY plane.

  In the first magnetic sensor 6A, the potential at the connection point of the MR elements 102 and 111 in the first magnetic sensor 6A and the potential in the first magnetic sensor 6A according to the intensity of the magnetic field component to be detected in the X direction. The potential at the connection point of the MR elements 104 and 113 changes. The first and second detection signals of the first magnetic sensor 6A represent the intensity of the magnetic field component to be detected in the X direction.

  In the second magnetic sensor 6B, the potential at the connection point of the MR elements 102 and 111 in the second magnetic sensor 6B and the potential in the second magnetic sensor 6B according to the strength of the magnetic field component to be detected in the Y direction. The potential at the connection point of the MR elements 104 and 113 changes. The first and second detection signals of the second magnetic sensor 6B represent the intensity of the magnetic field component to be detected in the Y direction.

  The magnetic sensor system in the present embodiment further includes two difference circuits 7A and 7B and a calculation unit 7C. Each of the difference circuits 7A and 7B and the calculation unit 7C has two input ends and one output end. The two input terminals of the difference circuit 7A are connected to the first and second output ports E1, E2 of the first magnetic sensor 6A, respectively. The two input terminals of the difference circuit 7B are connected to the first and second output ports E1, E2 of the second magnetic sensor 6B, respectively. The two input ends of the calculation unit 7C are connected to the output ends of the difference circuits 7A and 7B, respectively.

  The difference circuit 7A outputs a first calculation signal generated by a calculation including obtaining a difference between the first detection signal and the second detection signal of the first magnetic sensor 6A. The difference circuit 7B outputs a second calculation signal generated by calculation including obtaining a difference between the first detection signal and the second detection signal of the second magnetic sensor 6B. The calculation unit 7C calculates an output signal representing the direction and magnitude of the magnetic field to be detected based on the first and second calculation signals. The difference circuits 7A and 7B and the calculation unit 7C can be realized by a single microcomputer, for example.

  The first and second magnetic sensors 6A and 6B include a bias magnetic field generator configured by the magnetic field generator 9 according to the third embodiment, instead of the bias magnetic field generator in the present embodiment. It may be. Other configurations, operations, and effects in the present embodiment are the same as those in the third or sixth embodiment.

  In addition, this invention is not limited to said each embodiment, A various change is possible. For example, as long as the requirements of the claims are satisfied, the number, shape, and arrangement of the plurality of MR elements and the plurality of magnetic field generation units are not limited to the examples shown in the embodiments and are arbitrary.

  The MR element 10 may be configured by laminating the base layer 11, the free layer 15, the nonmagnetic layer 14, the magnetization fixed layer 13, the antiferromagnetic layer 12, and the protective layer 16 in this order from the lower electrode 40 side. Good.

  DESCRIPTION OF SYMBOLS 1, 2 ... Scale, 4, 5, 5A, 5B, 6A, 6B ... Magnetic sensor, 8 ... Bias magnetic field generator, 9 ... Magnetic field generator, 10 ... MR element, 13 ... Magnetization fixed layer, 14 ... Nonmagnetic layer DESCRIPTION OF SYMBOLS 15 ... Free layer, 20 ... Magnetic field generator, 100 ... Magnetic field generator, 200 ... Magnetic field generator, 210 ... First antiferromagnetic material part, 220 ... First ferromagnetic material part, 300 ... Magnetic field generator , 400 ... Magnetic field generator.

Claims (19)

A magnetic field generator including a plurality of magnetic field generators that generate a plurality of external magnetic fields arranged in a predetermined pattern,
Each of the plurality of magnetic field generators includes a first ferromagnetic part and a first antiferromagnetic part,
The first antiferromagnetic part is in contact with the first ferromagnetic part and exchange-coupled with the first ferromagnetic part;
The first ferromagnetic part has magnetization as the entire first ferromagnetic part,
The plurality of magnetic field generators include two magnetic field generators adjacent to each other and having different magnetization directions as the entire first ferromagnetic body part. The first ferromagnetic part includes a plurality of stacked constituent layers,
The magnetic field generator according to claim 1, wherein the plurality of constituent layers include a first ferromagnetic layer in contact with the first antiferromagnetic part.   The plurality of constituent layers further include a second ferromagnetic layer located farther from the first antiferromagnetic part than the first ferromagnetic layer. 2. The magnetic field generator according to 2.   4. The magnetic field generator according to claim 3, wherein the plurality of constituent layers further include a nonmagnetic layer interposed between the first ferromagnetic layer and the second ferromagnetic layer.   The first ferromagnetic layer and the second ferromagnetic layer are ferromagnetically exchange-coupled via the nonmagnetic layer, and the first ferromagnetic layer and the second ferromagnetic layer are either 5. The magnetic field generator according to claim 4, wherein the magnetic field generator has magnetization in the same direction as the magnetization of the entire first ferromagnetic portion.   The first ferromagnetic layer and the second ferromagnetic layer are antiferromagnetically exchange-coupled via the nonmagnetic layer, and the second ferromagnetic layer includes the first ferromagnetic body portion. 5. The magnetic field generator according to claim 4, wherein the magnetic field generator has magnetization in the same direction as the overall magnetization. The first ferromagnetic part has a first surface and a second surface facing away from each other,
The first antiferromagnetic part is in contact with the first surface of the first ferromagnetic part,
Each of the plurality of magnetic field generation units further includes a second antiferromagnetic part that is in contact with the second surface of the first ferromagnetic part and exchange-coupled with the first ferromagnetic part. The magnetic field generator according to claim 1, comprising:   The magnetic field generator according to claim 7, wherein the first antiferromagnetic part and the second antiferromagnetic part have different blocking temperatures. The first antiferromagnetic part has a first surface and a second surface that face away from each other,
The first ferromagnetic part is in contact with the first surface of the first antiferromagnetic part,
Each of the plurality of magnetic field generating portions further includes a second ferromagnetic portion that is in contact with the second surface of the first antiferromagnetic portion and exchange-coupled with the first antiferromagnetic portion. Including
The magnetic field generator according to claim 1, wherein the second ferromagnetic part has magnetization as the entire second ferromagnetic part. A plurality of magnetic detection elements for detecting a magnetic field to be detected;
A magnetic sensor comprising a bias magnetic field generator for generating a plurality of bias magnetic fields applied to the plurality of magnetic detection elements,
The bias magnetic field generator is constituted by the magnetic field generator according to any one of claims 1 to 9,
Each of the plurality of bias magnetic fields is caused by magnetization of the entire first ferromagnetic body portion in at least one magnetic field generation portion of the plurality of magnetic field generation portions. .   The magnetic sensor according to claim 10, wherein each of the plurality of magnetic detection elements is a magnetoresistive effect element.   The magnetoresistive effect element is disposed between a magnetization fixed layer having magnetization whose direction is fixed, a free layer whose magnetization changes according to a magnetic field to be detected, and between the magnetization fixed layer and the free layer The magnetic sensor according to claim 11, further comprising a nonmagnetic layer.   The magnetization direction of the entire first ferromagnetic body portion in the arbitrary magnetic field generation portion among the plurality of magnetic field generation portions is the magnetization direction of the entire first ferromagnetic body portion in the arbitrary magnetic field generation portion. The magnetic sensor according to claim 12, wherein the magnetic sensor intersects with the magnetization direction of the magnetization fixed layer of a specific magnetic detection element to which a bias magnetic field due to the magnetic field is applied. The plurality of magnetic detection elements include a first magnetic detection element and a second magnetic detection element connected in series,
The plurality of magnetic field generation units include first and second magnetic field generation units,
The bias magnetic field applied to the first magnetic detection element is caused by the magnetization of the first ferromagnetic body part as a whole in the first magnetic field generation part,
The bias magnetic field applied to the second magnetic detection element is caused by the magnetization of the entire first ferromagnetic body part in the second magnetic field generation part,
The first and second magnetic field generation units are adjacent to each other and have different magnetization directions as the whole of the first ferromagnetic body unit. The magnetic sensor described. The plurality of magnetic detection elements include a first magnetic detection element and a second magnetic detection element connected in series,
The plurality of magnetic field generators include first to fourth magnetic field generators,
The bias magnetic field applied to the first magnetic sensing element includes the magnetization of the first ferromagnetic body as a whole in the first magnetic field generator and the first ferromagnetic in the second magnetic field generator. Due to the magnetization of the whole body,
The bias magnetic field applied to the second magnetic detection element includes the magnetization of the first ferromagnetic body as a whole in the third magnetic field generator and the first ferromagnetic in the fourth magnetic field generator. Due to the magnetization of the whole body,
The first and third magnetic field generators are adjacent to each other and have different magnetization directions as the entire first ferromagnetic part,
The said 2nd and 4th magnetic field generation | occurrence | production part is adjacent, and the direction of the magnetization as said 1st ferromagnetic material part whole differs from each other, The one of Claim 10 thru | or 13 characterized by the above-mentioned. The magnetic sensor described. Half-bridge circuit,
A magnetic sensor comprising a bias magnetic field generator,
The half bridge circuit is
Including a first magnetic detection element array and a second magnetic detection element array connected in series;
The first magnetic detection element array is provided between a power supply port and an output port,
The second magnetic detection element array is provided between the output port and a ground port,
Each of the first magnetic detection element row and the second magnetic detection element row includes a plurality of magnetic detection elements connected in series for detecting a magnetic field to be detected,
The bias magnetic field generator is constituted by the magnetic field generator according to any one of claims 1 to 9, and a plurality of magnetic fields applied to a plurality of magnetic detection elements included in the first and second magnetic detection element arrays. Generate a bias magnetic field,
Each of the plurality of bias magnetic fields is caused by magnetization of the entire first ferromagnetic body portion in at least one magnetic field generation portion of the plurality of magnetic field generation portions,
The two magnetic field generators adjacent to each other and having different magnetization directions as the entire first ferromagnetic part are included in one of the first magnetic detection element array and the second magnetic detection element array. A magnetic sensor that generates at least one bias magnetic field applied to at least one magnetic detection element. Half-bridge circuit,
A magnetic sensor comprising a bias magnetic field generator,
The half bridge circuit is
Including a first magnetic detection element array and a second magnetic detection element array connected in series;
The first magnetic detection element array is provided between a power supply port and an output port,
The second magnetic detection element array is provided between the output port and a ground port,
Each of the first magnetic detection element row and the second magnetic detection element row includes a plurality of magnetic detection elements connected in series for detecting a magnetic field to be detected,
The bias magnetic field generator is constituted by the magnetic field generator according to any one of claims 1 to 9, and a plurality of magnetic fields applied to a plurality of magnetic detection elements included in the first and second magnetic detection element arrays. Generate a bias magnetic field,
Each of the plurality of bias magnetic fields is caused by magnetization of the entire first ferromagnetic body portion in at least one magnetic field generation portion of the plurality of magnetic field generation portions,
One of the two magnetic field generators adjacent to each other and having different magnetization directions as the whole of the first ferromagnetic part is a bias applied to a magnetic detection element included in the first magnetic detection element row A magnetic sensor for generating a magnetic field, wherein the other of the two magnetic field generation units generates a bias magnetic field applied to a magnetic detection element included in the second magnetic detection element array. Half-bridge circuit,
A magnetic sensor comprising a bias magnetic field generator,
The half bridge circuit is
Including a first magnetic detection element array and a second magnetic detection element array connected in series;
The first magnetic detection element array is provided between a power supply port and an output port,
The second magnetic detection element array is provided between the output port and a ground port,
Each of the first magnetic detection element row and the second magnetic detection element row includes a plurality of magnetic detection elements connected in series for detecting a magnetic field to be detected,
The bias magnetic field generator includes a plurality of magnetic field generators arranged in a predetermined pattern to generate a plurality of external magnetic fields, and is applied to a plurality of magnetic detection elements included in the first and second magnetic detection element arrays. Generate multiple bias magnetic fields,
Each of the plurality of magnetic field generation units includes a ferromagnetic part,
The ferromagnetic part has magnetization as the entire ferromagnetic part,
Each of the plurality of bias magnetic fields is caused by magnetization of the entire ferromagnetic body portion in at least one magnetic field generation portion of the plurality of magnetic field generation portions,
The plurality of magnetic field generation units are two magnetic field generation units adjacent to each other and having different magnetization directions as the entire ferromagnetic body unit, wherein the first magnetic detection element array and the second magnetic detection unit A magnetic sensor comprising: two magnetic field generators for generating at least one bias magnetic field applied to at least one magnetic detection element included in one of the element rows. Half-bridge circuit,
A magnetic sensor comprising a bias magnetic field generator,
The half bridge circuit is
Including a first magnetic detection element array and a second magnetic detection element array connected in series;
The first magnetic detection element array is provided between a power supply port and an output port,
The second magnetic detection element array is provided between the output port and a ground port,
Each of the first magnetic detection element row and the second magnetic detection element row includes a plurality of magnetic detection elements connected in series for detecting a magnetic field to be detected,
The bias magnetic field generator includes a plurality of magnetic field generators arranged in a predetermined pattern to generate a plurality of external magnetic fields, and is applied to a plurality of magnetic detection elements included in the first and second magnetic detection element arrays. Generate multiple bias magnetic fields,
Each of the plurality of magnetic field generation units includes a ferromagnetic part,
The ferromagnetic part has magnetization as the entire ferromagnetic part,
Each of the plurality of bias magnetic fields is caused by magnetization of the entire ferromagnetic body portion in at least one magnetic field generation portion of the plurality of magnetic field generation portions,
The plurality of magnetic field generation units include two magnetic field generation units adjacent to each other and having different magnetization directions as the entire ferromagnetic body unit,
One of the two magnetic field generation units generates a bias magnetic field to be applied to the magnetic detection elements included in the first magnetic detection element array, and the other of the two magnetic field generation units is the second magnetic detection unit. A magnetic sensor for generating a bias magnetic field applied to a magnetic detection element included in an element array.

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