Patent Publication Number: US-2022221536-A1

Title: Magnetic sensor and inspection device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No.2021-003368, filed on Jan. 13, 2021; the entire contents of which are incorporated herein by reference. 
     FIELD 
     Embodiments described herein relate generally to a magnetic sensor and an inspection device. 
     BACKGROUND 
     There is a magnetic sensor that uses a magnetic layer. There is an inspection device that uses the magnetic sensor. It is desirable to improve the characteristics of the magnetic sensor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  are schematic views illustrating a magnetic sensor according to a first embodiment; 
         FIGS. 2A to 2C  are schematic cross-sectional views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 3A and 3B  are graphs illustrating characteristics of the magnetic sensor; 
         FIG. 4  is a graph illustrating a characteristic of the magnetic sensor; 
         FIG. 5  is a schematic view illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 6A to 6D  are schematic views illustrating magnetic sensors according to the first embodiment; 
         FIGS. 7A to 7C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 8A to 8C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 9A to 9C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 10A to 10C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 11A to 11C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 12A to 12C  are schematic views illustrating the magnetic sensor according to the first embodiment; 
         FIGS. 13A and 13B  are schematic views illustrating characteristics of the magnetic sensor according to the first embodiment; 
         FIGS. 14A and 14B  are schematic views illustrating characteristics of the magnetic sensor according to the first embodiment; 
         FIGS. 15A to 15C  are graphs illustrating characteristics of the magnetic sensor according to the first embodiment; 
         FIGS. 16A and 16B  are schematic views illustrating a magnetic sensor according to the first embodiment; 
         FIG. 17  is a schematic view illustrating an inspection device according to a second embodiment; 
         FIG. 18  is a schematic view illustrating an inspection device according to the second embodiment; 
         FIG. 19  is a schematic perspective view showing an inspection device according to the second embodiment; 
         FIG. 20  is a schematic plan view showing the inspection device according to the second embodiment; 
         FIG. 21  is a schematic view showing the magnetic sensor and the inspection device according to the second embodiment; and 
         FIG. 22  is a schematic view showing the inspection device according to the second embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     According to one embodiment, a magnetic sensor includes a base body including a base body end portion, a magnetic member, and an element part. A direction from the base body toward the magnetic member is along a first direction. The element part includes a first magnetic element and a second magnetic element. An orientation from the first magnetic element toward the second magnetic element is along a second direction crossing the first direction. A portion of the first magnetic element and a portion of the second magnetic element are between the base body and the magnetic member in the first direction. A position in a third direction of an other portion of the first magnetic element and a position in the third direction of an other portion of the second magnetic element are between a position in the third direction of the base body end portion and a position in the third direction of the magnetic member. The third direction crosses a plane including the first and second directions. 
     According to one embodiment, an inspection device includes the magnetic sensor described above, and a processor configured to process a signal output from the magnetic sensor. 
     Various embodiments are described below with reference to the accompanying drawings. 
     The drawings are schematic and conceptual; and the relationships between the thickness and width of portions, the proportions of sizes among portions, etc., are not necessarily the same as the actual values. The dimensions and proportions may be illustrated differently among drawings, even for identical portions. 
     In the specification and drawings, components similar to those described previously or illustrated in an antecedent drawing are marked with like reference numerals, and a detailed description is omitted as appropriate. 
     First Embodiment 
       FIGS. 1A and 1B  are schematic views illustrating a magnetic sensor according to a first embodiment. 
       FIG. 1A  is a plan view.  FIG. 1B  is a cross-sectional view. 
       FIGS. 2A to 2C  are schematic cross-sectional views illustrating the magnetic sensor according to the first embodiment. 
     As shown in  FIGS. 1A and 1B , the magnetic sensor  110  according to the embodiment includes a base body  55 , a magnetic member  51 , and an element part  10 U. 
     The base body  55  includes a base body end portion  55   e.  The direction from the base body  55  toward the magnetic member  51  is along a first direction. The first direction is taken as a Y-axis direction. One direction perpendicular to the Y-axis direction is taken as an X-axis direction. A direction perpendicular to the Y-axis direction and the X-axis direction is taken as a Z-axis direction. 
     The element part  10 U includes a first magnetic element  11 E and a second magnetic element  12 E. In the example, the element part  10 U further includes a third magnetic element  13 E and a fourth magnetic element  14 E. 
     The orientation from the first magnetic element  11 E toward the second magnetic element  12 E is along a second direction. The second direction crosses the first direction (the Y-axis direction). The second direction is, for example, the X-axis direction. For example, the orientation from the first magnetic element  11 E toward the third magnetic element  13 E is along the second direction. The orientation from the first magnetic element  11 E toward the fourth magnetic element  14 E is along the second direction. For example, the multiple magnetic elements are arranged along the X-axis direction. The sequence of the arrangement of the multiple magnetic elements is arbitrary. 
     As shown in  FIG. 1A , the base body end portion  55   e  extends along the second direction (e.g., the X-axis direction). For example, the multiple magnetic elements are arranged along the base body end portion  55   e.  For example, distances dz 1  to dz 4  between the base body end portion  55   e  and each of the multiple magnetic elements (referring to  FIG. 1B  and  FIGS. 2A to 2C ) may be substantially the same. 
       FIG. 1B  is a cross-sectional view of the Y-Z plane that includes the first magnetic element  11 E.  FIG. 2A  is a cross-sectional view of the Y-Z plane that includes the second magnetic element  12 E.  FIG. 2B  is a cross-sectional view of the Y-Z plane that includes the third magnetic element  13 E.  FIG. 2C  is a cross-sectional view of the Y-Z plane that includes the fourth magnetic element  14 E. 
     As shown in  FIGS. 1B and 2B , a portion  11 P of the first magnetic element  11 E and a portion  12 P of the second magnetic element  12 E are between the base body  55  and the magnetic member  51  in the first direction (the Y-axis direction). The portion  11 P of the first magnetic element  11 E and the portion  12 P of the second magnetic element  12 E overlap the magnetic member  51  in the first direction (the Y-axis direction). Another portion  11 Q of the first magnetic element  11 E and another portion  12 Q of the second magnetic element  12 E do not overlap the magnetic member  51  in the first direction (the Y-axis direction). 
     As shown in  FIGS. 2B and 2C , a portion  13 P of the third magnetic element  13 E and a portion  14 P of the fourth magnetic element  14 E are between the base body  55  and the magnetic member  51  in the first direction (the Y-axis direction). The portion  13 P of the third magnetic element  13 E and the portion  14 P of the fourth magnetic element  14 E overlap the magnetic member  51  in the first direction (the Y-axis direction). Another portion  13 Q of the third magnetic element  13 E and another portion  14 Q of the fourth magnetic element  14 E do not overlap the magnetic member  51  in the first direction (the Y-axis direction). 
     A direction that crosses a plane (the Y-X plane) including the first and second directions is taken as a third direction. The third direction is, for example, the Z-axis direction. 
     As shown in  FIG. 1B , for example, the position in the third direction (the Z-axis direction) of the other portion  11 Q of the first magnetic element  11 E is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of the magnetic member  51 . 
     As shown in  FIG. 2A , for example, the position in the third direction (the Z-axis direction) of the other portion  12 Q of the second magnetic element  12 E is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of the magnetic member  51 . 
     As shown in  FIG. 2B , for example, the position in the third direction (the Z-axis direction) of the other portion  13 Q of the third magnetic element  13 E is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of the magnetic member  51 . 
     As shown in  FIG. 2C , for example, the position in the third direction (the Z-axis direction) of the other portion  14 Q of the fourth magnetic element  14 E is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of the magnetic member  51 . 
     Thus, a portion of each of the multiple magnetic elements overlaps the magnetic member  51 ; and another portion of each of the multiple magnetic elements does not overlap the magnetic member  51 . 
     As shown in  FIGS. 1A and 1B , the magnetic sensor  110  is configured to face a detection object  80 . The detection object  80  is, for example, the inspection object. The detection object  80  includes, for example, a local magnetic field source. The detection object  80  includes, for example, at least an inspection conductive member  80   c  such as a metal, etc. For example, the magnetic sensor  110  is configured to detect a magnetic field (a current magnetic field) caused by a current that flows in the inspection conductive member  80   c.    
     For example, the magnetic flux of the current magnetic field is concentrated by the magnetic member  51 . The magnetic flux that is concentrated by the magnetic member  51  is efficiently applied to the element part  10 U (the multiple magnetic elements). For example, the magnetic member  51  functions as a MFC (Magnetic Flux Concentrator). 
     As shown in  FIG. 1B , the first magnetic element  11 E includes a first magnetic layer  11 , a first counter magnetic layer  110 , and a first nonmagnetic layer  11   n.  The first nonmagnetic layer  11   n  is located between the first magnetic layer  11  and the first counter magnetic layer  11   o.    
     As shown in  FIG. 2A , the second magnetic element  12 E includes a second magnetic layer  12 , a second counter magnetic layer  12   o,  and a second nonmagnetic layer  12   n.  The second nonmagnetic layer  12   n  is located between the second magnetic layer  12  and the second counter magnetic layer  12   o.    
     As shown in  FIG. 2B , the third magnetic element  13 E includes a third magnetic layer  13 , a third counter magnetic layer  13   o,  and a third nonmagnetic layer  13   n.  The third nonmagnetic layer  13   n  is located between the third magnetic layer  13  and the third counter magnetic layer  13   o.    
     As shown in  FIG. 2C , the fourth magnetic element  14 E includes a fourth magnetic layer  14 , a fourth counter magnetic layer  14   o,  and a fourth nonmagnetic layer  14   n.  The fourth nonmagnetic layer  14   n  is located between the fourth magnetic layer  14  and the fourth counter magnetic layer  14   o.    
     The first to fourth magnetic layers  11  to  14  and the first to fourth counter magnetic layers  11   o  to  14   o  include at least one selected from the group consisting of Fe, Co, and Ni. These magnetic layers are, for example, ferromagnetic layers. The first to fourth nonmagnetic layers  11   n  to  14   n  include, for example, a conductive material such as Cu, etc. The first to fourth magnetic elements  11 E to  14 E are, for example, GMR (Giant Magneto Resistance) elements. The first to fourth magnetic elements  11 E to  14 E may be, for example, TMR (Tunnel Magneto Resistance) elements. 
     For example, the electrical resistances of the first to fourth magnetic elements  11 E to  14 E change according to the magnetic field from the detection object  80 . For example, in each of these magnetic elements, the orientation of the magnetization of at least one of the magnetic layer or the counter magnetic layer changes according to the magnetic field. The angle between the magnetization of the magnetic layer and the magnetization of the counter magnetic layer changes due to the change of the orientation of the magnetization. The electrical resistances of the first to fourth magnetic elements  11 E to  14 E change according to the changes of the angles. The magnetic field from the detection object  80  is detected by detecting the change of the electrical resistance. 
     According to the embodiment, the magnetic field from the detection object  80  is concentrated by the magnetic member  51 ; and the concentrated magnetic field is applied to the first to fourth magnetic elements  11 E to  14 E. A portion of each of the multiple magnetic elements overlaps the magnetic member  51 ; and another portion of each of the multiple magnetic elements does not overlap the magnetic member  51 ; thereby, the magnetic field is more efficiently applied to the magnetic elements. Higher sensitivity is obtained thereby. A magnetic sensor with improved sensing characteristics can be provided. 
     As shown in  FIG. 1B , the length along the third direction (the Z-axis direction) of the portion  11 P of the first magnetic element  11 E is taken as a length dP 1 . The length along the third direction of the first magnetic element  11 E is taken as a length Lz 1 . According to the embodiment, it is favorable for the length dP 1  to be not more than 0.5 times the length Lz 1 . The length Lz 1  is the sum of the length dP 1  and a length dQ 1  along the Z-axis direction of the other portion  11 Q of the first magnetic element  11 E. For example, the length dP 1  may be not less than 0.001 times the length Lz 1 . As described below, it is more favorable for the ratio of the length dP 1  to the length Lz 1  to be not more than 0.4 times. 
     As shown in  FIG. 2A , the length along the third direction (the Z-axis direction) of the portion  12 P of the second magnetic element  12 E is taken as a length dP 2 . The length along the third direction of the second magnetic element  12 E is taken as a length Lz 2 . According to the embodiment, it is favorable for the length dP 2  to be not more than 0.5 times the length Lz 2 . The length Lz 2  is the sum of the length dP 2  and a length dQ 2  along the Z-axis direction of the other portion  12 Q of the second magnetic element  12 E. For example, the length dP 2  may be not less than 0.001 times the length Lz 2 . 
     As shown in  FIG. 2B , the length along the third direction (the Z-axis direction) of the portion  13 P of the third magnetic element  13 E is taken as a length dP 3 . The length along the third direction of the third magnetic element  13 E is taken as a length Lz 3 . According to the embodiment, it is favorable for the length dP 3  to be not more than 0.5 times the length Lz 3 . The length Lz 3  is the sum of the length dP 3  and a length dQ 3  along the Z-axis direction of the other portion  13 Q of the third magnetic element  13 E. For example, the length dP 3  may be not less than 0.001 times the length Lz 3 . 
     As shown in  FIG. 2C , the length along the third direction (the Z-axis direction) of the portion  14 P of the fourth magnetic element  14 E is taken as a length dP 4 . The length along the third direction of the fourth magnetic element  14 E is taken as a length Lz 4 . According to the embodiment, it is favorable for the length dP 4  to be not more than 0.5times the length Lz 4 . The length Lz 4  is the sum of the length dP 4  and a length dQ 4  along the Z-axis direction of the other portion  14 Q of the fourth magnetic element  14 E. For example, the length dP 4  may be not less than 0.001 times the length Lz 4 . Examples of the relationships between the characteristics and the lengths described above are described below. 
     As shown in  FIG. 1B , the distance along the third direction (the Z-axis direction) between the base body end portion  55   e  and the first magnetic element  11 E is taken as the distance dz 1 . For example, it is favorable for the distance dz 1  to be not less than 0.1 times and not more than 100 times the length Lz 1  along the third direction of the first magnetic element  11 E. 
     As shown in  FIG. 2A , the distance along the third direction (the Z-axis direction) between the base body end portion  55   e  and the second magnetic element  12 E is taken as the distance dz 2 . For example, it is favorable for the distance dz 2  to be not less than 0.1 times and not more than 100 times the length Lz 2  along the third direction of the second magnetic element  12 E. 
     As shown in  FIG. 2B , the distance along the third direction (the Z-axis direction) between the base body end portion  55   e  and the third magnetic element  13 E is taken as the distance dz 3 . For example, it is favorable for the distance dz 3  to be not less than 0.1 times and not more than 100 times the length Lz 3  along the third direction of the third magnetic element  13 E. 
     As shown in  FIG. 2C , the distance along the third direction (the Z-axis direction) between the base body end portion  55   e  and the fourth magnetic element  14 E is taken as the distance dz 4 . For example, it is favorable for the distance dz 4  to be not less than 0.1 times and not more than 100 times the length Lz 4  along the third direction of the fourth magnetic element  14 E. 
     Because all the distances dz 1 , dz 2 , dz 3  and dz 4  are short, the distances between the detection object  80  and the multiple magnetic elements can be short. The magnetic field from the detection object  80  can be effectively applied to the multiple magnetic elements before it spread out to the air. For example, the spatial resolution of the detection can be increased. A magnetic sensor with improved sensing characteristics can be provided. 
     An example of simulation results of the characteristics of the magnetic sensor will now be described. A simulation when one magnetic element (the first magnetic element  11 E) is included will now be described. 
     The model of the simulation includes a conducting wire that is used as the inspection conductive member  80   c.  The distance along the Y-axis direction between the conducting wire and the first magnetic element  11 E is 20 μm. In the simulation, the distribution of the magnetic field generated by a current flow in the conducting wire was calculated using a finite element method. The average value of the magnetic flux density inside the first magnetic element  11 E was evaluated as an index of the magnitude of the convergence of the magnetic flux due to the magnetic member  51 . 
     The characteristics were calculated in advance for the case when the position in the Y-axis direction of the conducting wire is changed. In the calculation, it was found that spatial resolution of detecting the current magnetic field generated by the conducting wire was the same between the case when the magnetic member  51  is included and the case when the magnetic member  51  is not included. When the magnetic member  51  is included, compared to when the magnetic member  51  is not included, more magnetic flux can be converged while maintaining the spatial resolution. The sensitivity can be increased when the magnetic member  51  is included. 
       FIGS. 3A and 3B  are graphs illustrating characteristics of the magnetic sensor. 
     The horizontal axis of  FIG. 3A  is a ratio Rd 1 . The ratio Rd 1  is the ratio of a distance dPz to the length Lz 1 . dPz is described below. The distance dPz is the distance along the Z-axis direction between the end portion in the Z-axis direction of the first magnetic element  11 E and the end portion in the Z-axis direction of the magnetic member  51 . When the distance dPz is positive, the first magnetic element  11 E does not overlap the magnetic member  51  in the Y-axis direction. When the distance dPz is negative, the first magnetic element  11 E overlaps the magnetic member  51  in the Y-axis direction. When the distance dPz is negative, the absolute value of the distance dPz corresponds to the length (the width) of the portion (the portion  11 P) of the first magnetic element  11 E that overlaps the magnetic member  51  along the Z-axis direction. When the ratio Rd 1  is positive, the first magnetic element  11 E does not overlap the magnetic member  51  in the Y-axis direction. When the ratio Rd 1  is negative, the first magnetic element  11 E overlaps the magnetic member  51  in the Y-axis direction. 
     On the other hand, as described above, the length Lz 1  corresponds to the length (the width) in the Z-axis direction of the first magnetic element  11 E. When the ratio Rd 1  is negative, the absolute value of the ratio Rd 1  corresponds to the ratio of the length dP 1  to the length Lz 1 . 
     The vertical axis of  FIG. 3A  is a gain PG 1 . The gain PG 1  is an amount that corresponds to the amount of the magnetic flux converged to the inside of the first magnetic element  11 E by the magnetic member  51 . The gain PG 1  is normalized by the amount of the magnetic flux converged inside the first magnetic element  11 E when the magnetic member  51  is not included. When the gain PG 1  is greater than 1, large amount of the magnetic flux is converged by the magnetic member  51 , and the sensitivity increases. When the gain PG 1  is greater than 1, high sensitivity is obtained. 
     As shown in  FIG. 3A , a high gain PG 1  is obtained when the ratio Rd 1  is negative. Thus, it is favorable for the portion  11 P of the first magnetic element  11 E to overlap the magnetic member  51  in the Y-axis direction. A high gain PG 1  is obtained thereby, and high sensitivity is obtained. 
     As shown in  FIG. 3A , the gain PG 1  decreases when the ratio Rd 1  is negative and the absolute value of the ratio Rd 1  is excessively large. 
     As described above, the gain PG 1  changes with the ratio Rd 1 . As shown in  FIG. 3A , the gain PG 1  changes with the distance dz 1 . 
     The horizontal axis of  FIG. 3B  is the ratio Rd 1 . The vertical axis of  FIG. 3B , a normalized gain PG 2 . The normalized gain PG 2  is the value of the gain PG 1  shown in  FIG. 3A  normalized by the gain PG 1  when the ratio Rd 1  is +0.2. When the ratio Rd 1  is +0.2, the distance between the end portion of the first magnetic element  11 E and the end portion of the magnetic member  51  along the Z-axis direction is 1 μm. When the normalized gain PG 2  is not less than 1, the sensitivity can be increased by setting the ratio Rd 1  being negative. 
     It can be seen from  FIG. 3B  that the normalized gain PG 2  is not less than 1 when the distance dz 1  is 10 μm and when the absolute value of the ratio Rd 1  is not more than about 0.4. Thus, it is favorable for the absolute value of the ratio Rd 1  to be not more than 0.4. As described above, the first magnetic element  11 E overlaps the magnetic member  51  in the Y-axis direction when the distance dPz is negative (the ratio Rd 1  is negative). Accordingly, it is favorable for the first magnetic element  11 E to overlap the magnetic member  51  in the Y-axis direction and for the ratio (dP 1 /Lz 1 ) of the length dP 1  to the length Lz 1  to be not more than 0.4. 
       FIG. 4  is a graph illustrating a characteristic of the magnetic sensor. 
     The horizontal axis of  FIG. 4A  is a ratio Rd 2 . The ratio Rd 2  is the ratio of the distance dz 1  between the base body end portion  55   e  and the first magnetic element  11 E to the length Lz 1  along the third direction (the Z-axis direction) of the first magnetic element  11 E (i.e., dz 1 /Lz 1 ). The vertical axis of  FIG. 4  is the gain PG 1 .  FIG. 4  shows all of the values of  FIG. 3B  that satisfy dP 1 /Lz 1  being not more than 0.4. It can be seen from  FIG. 4  that the gain PG 1  is greater than 2 when the ratio Rd 2  is not less than 1.5. According to the embodiment, it is favorable for the ratio Rd 2  (i.e., dz 1 /Lz 1 ) to be not less than 1.5. The ratio Rd 2  may be not less than 2.0. 
     Examples of the multiple magnetic elements will now be described. 
     As shown in  FIG. 1A , the length along the second direction (e.g., the X-axis direction) of the first magnetic element  11 E is taken as a length Lx 1 . For example, the length Lx 1  is greater than the length Lz 1  along the third direction (the Z-axis direction) of the first magnetic element  11 E. The length along the second direction (e.g., the X-axis direction) of the second magnetic element  12 E is taken as a length Lx 2 . For example, the length Lx 2  is greater than the length Lz 2  along the third direction (the Z-axis direction) of the second magnetic element  12 E. The length along the second direction (e.g., the X-axis direction) of the third magnetic element  13 E is taken as a length Lx 3 . For example, the length Lx 3  is greater than the length Lz 3  along the third direction (the Z-axis direction) of the third magnetic element  13 E. The length along the second direction (e.g., the X-axis direction) of the fourth magnetic element  14 E is taken as a length Lx 4 . For example, the length Lx 4  is greater than the length Lz 4  along the third direction (the Z-axis direction) of the fourth magnetic element  14 E. Because the lengths Lz 1  to Lz 4  are short, for example, a magnetic field from the detection object  80  that has a component in the third direction (the Z-axis direction) can be efficiently detected. Because all the lengths of Lz 1 , Lz 2 , Lz 3  and Lz 4  are short, for example, the distance between the magnetic member  51  and the detection object  80  can be short. A higher spatial resolution is obtained. 
     For example, it is favorable for the length Lx 1  along the second direction of the first magnetic element  11 E to be not less than 5 times the length Lz 1  along the third direction of the first magnetic element  11 E. For example, it is favorable for the length Lx 2  along the second direction of the second magnetic element  12 E to be not less than 5 times the length Lz 2  along the third direction of the second magnetic element  12 E. For example, it is favorable for the length Lx 3  along the second direction of the third magnetic element  13 E to be not less than 5 times the length Lz 3  along the third direction of the third magnetic element  13 E. For example, it is favorable for the length Lx 4  along the second direction of the fourth magnetic element  14 E to be not less than 5 times the length Lz 4  along the third direction of the fourth magnetic element  14 E. By such aspect ratios, the orientation of the magnetization of the magnetic layer and the counter magnetic layer of each of the multiple magnetic elements can be stabilized at the initial state. More stable detection is possible. 
     As shown in  FIG. 1B , the length along the first direction (the Y-axis direction) of the magnetic member  51  is taken as a length Ly 51  (the thickness). It is favorable for the length Ly 51  to be greater than a length Ly 11  (the thickness) along the first direction of the first magnetic element  11 E. As shown in  FIG. 2A , it is favorable for the length Ly 51  to be greater than a length Ly 12  (the thickness) along the first direction of the second magnetic element  12 E. As shown in  FIG. 2B , it is favorable for the length Ly 51  to be greater than a length Ly 13  (the thickness) along the first direction of the third magnetic element  13 E. As shown in  FIG. 2C , it is favorable for the length Ly 51  to be greater than a length Ly 14  (the thickness) along the first direction of the fourth magnetic element  14 E. Because the magnetic member  51  is thick, the magnetic field from the detection object  80  can be more effectively concentrated, and the concentrated magnetic field can be effectively applied to the multiple magnetic elements. For example, higher sensitivity is easily obtained. For example, the length Ly 51  is not less than 2 times the length Ly 11 . The length Ly 51  may be not more than 1000 times the length Ly 11 . 
     As shown in  FIG. 1B , the distance along the first direction (the Y-axis direction) between the first magnetic element  11 E (the portion  11 P) and the magnetic member  51  is taken as a distance dy 1 . It is favorable for the distance dy 1  to be, for example, not less than 1/1000 times the length Lz 1  and not more than 2 times the length Ly 51 . As shown in  FIG. 2A , the distance along the first direction (the Y-axis direction) between the second magnetic element  12 E (the portion  12 P) and the magnetic member  51  is taken as a distance dy 2 . It is favorable for the distance dy 2  to be, for example, not less than 1/1000 times the length Lz 2  and not more than 2 times the length Ly 51 . As shown in  FIG. 2B , the distance along the first direction (the Y-axis direction) between the third magnetic element  13 E (the portion  13 P) and the magnetic member  51  is taken as a distance dy 3 . It is favorable for the distance dy 3  to be, for example, not less than 1/1000 times the length Lz 3  and not more than 2 times the length Ly 51 . As shown in  FIG. 2C , the distance along the first direction (the Y-axis direction) between the fourth magnetic element  14 E (the portion  14 P) and the magnetic member  51  is taken as a distance dy 4 . It is favorable for the distance dy 4  to be, for example, not less than 1/1000 times the length Lz 4  and not more than 2 times the length Ly 51 . Because all the distances of dy 1 , sy 2 , dy 3  and dy 4  are short, the magnetic field that is concentrated by the magnetic member  51  can be effectively applied to the multiple magnetic elements. For example, higher sensitivity is easily obtained. The distances of dy 1 , dy 2 , dy 3  and dy 4  are, for example, not less than 5 nm. For example, high manufacturability is obtained thereby. 
     As shown in  FIGS. 1B and 2A , the element part  10 U may further include a first connection member  15   a.  As described below, the first connection member  15   a  is electrically connected with a portion of the first magnetic element  11 E. At least a portion of the first connection member  15   a  is between the base body  55  and the magnetic member  51  in the first direction (the Y-axis direction). 
     As shown in  FIG. 2A , the element part  10 U may further include a second connection member  15   b.  As described below, the second connection member  15   b  is electrically connected with another portion of the first magnetic element  11 E. The position in the third direction (the Z-axis direction) of the second connection member  15   b  is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of at least one of the first magnetic element  11 E or the second magnetic element  12 E. In the example, at least a portion of the second magnetic element  12 E is between at least a portion of the second connection member  15   b  and at least a portion of the first connection member  15   a  in the third direction (the Z-axis direction). 
     As shown in  FIGS. 2B and 2C , the element part  10 U may further include a third connection member  15   c.  As described below, the third connection member  15   c  is electrically connected with one of the second magnetic element  12 E, the third magnetic element  13 E, or the fourth magnetic element  14 E. At least a portion of the third connection member  15   c  is between the base body  55  and the magnetic member  51  in the first direction (the Y-axis direction). 
     As shown in  FIG. 2C , the element part  10 U may further include a fourth connection member  15   d.  As described below, the fourth connection member  15   d  is electrically connected with one of the second magnetic element  12 E, the third magnetic element  13 E, or the fourth magnetic element  14 E. The position in the third direction (the Z-axis direction) of the fourth connection member  15   d  is between the position in the third direction of the base body end portion  55   e  and the position in the third direction of one of the second magnetic element  12 E, the third magnetic element  13 E, or the fourth magnetic element  14 E. In the example, at least a portion of the fourth magnetic element  14 E is between at least a portion of the fourth connection member  15   d  and at least a portion of the third connection member  15   c  in the third direction (the Z-axis direction). 
     The multiple magnetic elements are electrically connected by such connection members. The distance between the base body end portion  55   e  and the multiple magnetic elements can be short. A portion of each of the multiple magnetic elements is easily located between the base body  55  and the magnetic member  51 . 
     As shown in  FIG. 1A  and  FIGS. 2A to 2C , the magnetic sensor  110  may include an insulating member  65 . For example, a portion of the insulating member  65  is located between the magnetic member  51  and the multiple magnetic elements. For example, the multiple magnetic elements are located between the base body  55  and the insulating member  65 . For example, the connection members are located between the base body  55  and the insulating member  65 . By providing the insulating member  65 , stable insulation of the conductive member is obtained. 
     As shown in  FIG. 1A  and  FIGS. 2A to 2C , the element part  10 U may include a conductive member  20 . For example, the conductive member  20  includes first to fourth corresponding portions  21  to  24 . The first corresponding portion  21  corresponds to the first magnetic element  11 E. The second corresponding portion  22  corresponds to the second magnetic element  12 E. The third corresponding portion  23  corresponds to the third magnetic element  13 E. The fourth corresponding portion  24  corresponds to the fourth magnetic element  14 E. 
     For example, the first corresponding portion  21  overlaps the first magnetic element  11 E in the first direction (the Y-axis direction). The second corresponding portion  22  overlaps the second magnetic element  12 E in the first direction. The third corresponding portion  23  overlaps the third magnetic element  13 E in the first direction. The fourth corresponding portion  24  overlaps the fourth magnetic element  14 E in the first direction. 
     As described below, the first current that includes an alternating current component is supplied to the conductive member  20 . By using the first current, the magnetic field from the detection object  80  can be detected with higher sensitivity. 
     Examples of electrical connections of the multiple magnetic elements and the conductive member  20  will now be described. 
       FIG. 5  is a schematic view illustrating the magnetic sensor according to the first embodiment. 
       FIG. 5  shows an example of an electrical connection of the first to fourth magnetic elements  11 E to  14 E. In the illustration of  FIG. 5 , the spatial arrangement of the first to fourth magnetic elements  11 E to  14 E is modified from the example of  FIG. 1A  so that the electrical connectional relationship is easy to understand. 
     As shown in  FIG. 5 , the first magnetic element  11 E includes one end portion  11 Ee and another end portion  11 Ef. The direction from the one end portion  11 Ee toward the other end portion  11 Ef is along the X-axis direction. The second magnetic element  12 E includes one end portion  12 Ee and another end portion  12 Ef. The direction from the one end portion  12 Ee toward the other end portion  12 Ef is along the X-axis direction. The third magnetic element  13 E includes one end portion  13 Ee and another end portion  13 Ef. The direction from the one end portion  13 Ee toward the other end portion  13 Ef is along the X-axis direction. The fourth magnetic element  14 E includes one end portion  14 Ee and another end portion  14 Ef. The direction from the one end portion  14 Ee toward the other end portion  14 Ef is along the X-axis direction. The one end portion  11 Ee and the other end portion  11 Ef may be interchanged with each other. The one end portion  12 Ee and the other end portion  12 Ef may be interchanged with each other. The one end portion  13 Ee and the other end portion  13 Ef may be interchanged with each other. The one end portion  14 Ee and the other end portion  14 Ef may be interchanged with each other. 
     As shown in  FIG. 5 , the other end portion  11 Ef of the first magnetic element  11 E is electrically connected with the one end portion  12 Ee of the second magnetic element  12 E. The one end portion  11 Ee of the first magnetic element  11 E is electrically connected with the one end portion  13 Ee of the third magnetic element  13 E. The other end portion  13 Ef of the third magnetic element  13 E is electrically connected with the one end portion  14 Ee of the fourth magnetic element  14 E. The other end portion  12 Ef of the second magnetic element  12 E is electrically connected with the other end portion  14 Ef of the fourth magnetic element  14 E. Thus, the first to fourth magnetic elements  11 E to  14 E have a bridge connection. 
     As shown in  FIG. 5 , the magnetic sensor  110  may further include an element current circuit  75 . The element current circuit  75  is configured to supply an element current Id between a first connection point CP 1  and a second connection point CP 2 , in which the first connection point CP 1  is between the one end portion  11 Ee of the first magnetic element  11 E and the one end portion  13 Ee of the third magnetic element  13 E, and the second connection point CP 2  is between the other end portion  12 Ef of the second magnetic element  12 E and the other end portion  14 Ef of the fourth magnetic element  14 E. 
     As shown in  FIG. 5 , the magnetic sensor  110  may further include a detection circuit  73 . The detection circuit  73  is configured to detect the change of the potential between a third connection point CP 3  and a fourth connection point CP 4 , in which the third connection point CP 3  is between the other end portion  11 Ef of the first magnetic element  11 E and the one end portion  12 Ee of the second magnetic element  12 E, and the fourth connection point CP 4  is between the other end portion  13 Ef of the third magnetic element  13 E and the one end portion  14 Ee of the fourth magnetic element  14 E. 
       FIGS. 6A to 6D  are schematic views illustrating magnetic sensors according to the first embodiment.  FIGS. 6B to 6D  show several examples of the electrical connection of the conductive member  20 . In the illustrations of  FIGS. 6A to 6D , the spatial arrangement of the first to fourth corresponding portions  21  to  24  is modified from the example of  FIG. 1A  so that the electrical connectional relationship is easy to understand. The configuration of the magnetic element illustrated in  FIG. 5  may be combined with any of the configurations shown in  FIGS. 6A  to  6 D. 
     As shown in  FIG. 6A , the first corresponding portion  21  includes a first corresponding one-portion  21   e  and a first corresponding other-portion  21   f.  For example, the first corresponding one-portion  21   e  corresponds to the one end portion  11 Ee of the first magnetic element  11 E. For example, the first corresponding other-portion  21   f  corresponds to the other end portion  11 Ef of the first magnetic element  11 E. For example, the first corresponding one-portion  21   e  overlaps the one end portion  11 Ee of the first magnetic element  11 E in the first direction (the Y-axis direction). For example, the first corresponding other-portion  21   f  overlaps the other end portion  11 Ef of the first magnetic element  11 E in the first direction. 
     As shown in  FIG. 6A , the second corresponding portion  22  includes a second corresponding one-portion  22   e  and a second corresponding other-portion  22   f.  For example, the second corresponding one-portion  22   e  corresponds to the one end portion  12 Ee of the second magnetic element  12 E. For example, the second corresponding other-portion  22   f  corresponds to the other end portion  12 Ef of the second magnetic element  12 E. For example, the second corresponding one-portion  22   e  overlaps the one end portion  12 Ee of the second magnetic element  12 E in the first direction (the Y-axis direction). For example, the second corresponding other-portion  22   f  overlaps the other end portion  12 Ef of the second magnetic element  12 E in the first direction. 
     As shown in  FIG. 6A , the third corresponding portion  23  includes a third corresponding one-portion  23   e  and a third corresponding other-portion  23   f.  For example, the third corresponding one-portion  23   e  corresponds to the one end portion  13 Ee of the third magnetic element  13 E. For example, the third corresponding other-portion  23   f  corresponds to the other end portion  13 Ef of the third magnetic element  13 E. For example, the third corresponding one-portion  23   e  overlaps the one end portion  13 Ee of the third magnetic element  13 E in the first direction (the Y-axis direction). For example, the third corresponding other-portion  23   f  overlaps the other end portion  13 Ef of the third magnetic element  13 E in the first direction. 
     As shown in  FIG. 6A , the fourth corresponding portion  24  includes a fourth corresponding one-portion  24   e  and a fourth corresponding other-portion  24   f.  For example, the fourth corresponding one-portion  24   e  corresponds to the one end portion  14 Ee of the fourth magnetic element  14 E. For example, the fourth corresponding other-portion  24   f  corresponds to the other end portion  14 Ef of the fourth magnetic element  14 E. For example, the fourth corresponding one-portion  24   e  overlaps the one end portion  14 Ee of the fourth magnetic element  14 E in the first direction (the Y-axis direction). For example, the fourth corresponding other-portion  24   f  overlaps the other end portion  14 Ef of the fourth magnetic element  14 E in the first direction. 
     In the example shown in  FIG. 6A , the first corresponding one-portion  21   e  is electrically connected with the third corresponding one-portion  23   e.  The first corresponding other-portion  21   f  is electrically connected with the second corresponding one-portion  22   e.  The third corresponding other-portion  23   f  is electrically connected with the fourth corresponding one-portion  24   e.  The second corresponding other-portion  22   f  is electrically connected with the fourth corresponding other-portion  24   f.    
     As shown in  FIG. 6A , the magnetic sensor  110  may further include a first current circuit  71 . The first current circuit  71  is configured to supply a first current I 1  that includes an alternating current between a fifth connection point CP 5  and a sixth connection point CP 6 , in which the fifth connection point CP 5  is between the first corresponding other-portion  21   f  and the second corresponding one-portion  22   e,  and the sixth connection point CP 6  is between the third corresponding other-portion  23   f  and the fourth corresponding one-portion  24   e.    
     The magnetic field that is generated by the first current I 1  flowing through the first corresponding portion  21  is applied to the first magnetic element  11 E. The magnetic field that is generated by the first current I 1  flowing through the second corresponding portion  22  is applied to the second magnetic element  12 E. The magnetic field that is generated by the first current I 1  flowing through the third corresponding portion  23  is applied to the third magnetic element  13 E. The magnetic field that is generated by the first current I 1  flowing through the fourth corresponding portion  24  is applied to the fourth magnetic element  14 E. 
     For example, the element current Id may be a substantially direct current. The orientation of the element current Id is as shown in  FIG. 5 . The element current Id flows through the first magnetic element  11 E in the orientation from the one end portion  11 Ee of the first magnetic element  11 E toward the other end portion  11 Ef of the first magnetic element  11 E. The element current Id flows through the second magnetic element  12 E in the orientation from the one end portion  12 Ee of the second magnetic element  12 E toward the other end portion  12 Ef of the second magnetic element  12 E. The element current Id flows through the third magnetic element  13 E in the orientation from the one end portion  13 Ee of the third magnetic element  13 E toward the other end portion  13 Ef of the third magnetic element  13 E. The element current Id flows through the fourth magnetic element  14 E in the orientation from the one end portion  14 Ee of the fourth magnetic element  14 E toward the other end portion  14 Ef of the fourth magnetic element  14 E. 
     In the example shown in  FIG. 6A , for example, the orientation of the first current I 1  at one time (a first time) when the first current I 1  that includes the alternating current component is supplied to the conductive member  20  is as follows. The first current I 1  flows through the first corresponding portion  21  in the orientation from the first corresponding other-portion  21   f  toward the first corresponding one-portion  21   e.  The first current I 1  flows through the second corresponding portion  22  in the orientation from the second corresponding one-portion  22   e  toward the second corresponding other-portion  22   f.  The first current I 1  flows through the third corresponding portion  23  in the orientation from the third corresponding one-portion  23   e  toward the third corresponding other-portion  23   f.  The first current I 1  flows through the fourth corresponding portion  24  in the orientation from the fourth corresponding other-portion  24   f  toward the fourth corresponding one-portion  24   e.    
     For example, the relationship between the orientation of the first current I 1  flowing through the second corresponding portion  22  at the first time and the orientation of the element current Id flowing through the second magnetic element  12 E is opposite to (the opposite phase of) the relationship between the orientation of the first current I 1  flowing through the first corresponding portion  21  at the first time and the orientation of the element current Id flowing through the first magnetic element  11 E. The relationship between the orientation of the first current I 1  flowing through the fourth corresponding portion  24  at the first time and the orientation of the element current Id flowing through the fourth magnetic element  14 E is opposite to (the opposite phase of) the relationship between the orientation of the first current I 1  flowing through the third corresponding portion  23  at the first time and the orientation of the element current Id flowing through the third magnetic element  13 E. 
     At the first time in the example shown in  FIG. 6A , the first current I 1  has the orientation from the first corresponding other-portion  21   f  toward the first corresponding one-portion  21   e,  the orientation from the second corresponding one-portion  22   e  toward the second corresponding other-portion  22   f,  the orientation from the third corresponding one-portion  23   e  toward the third corresponding other-portion  23   f,  and the orientation from the fourth corresponding other-portion  24   f  toward the fourth corresponding one-portion  24   e.    
     In the example shown in  FIG. 6A , a first circuit that includes the first and third corresponding portions  21  and  23  that are connected in series is provided. A second circuit that includes the second and fourth corresponding portions  22  and  24  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. 
     The noise can be further suppressed by such a combination of the first to fourth magnetic elements  11 E to  14 E and the first to fourth corresponding portions  21  to  24 . Examples of the signals obtained from the first to fourth magnetic elements  11 E to  14 E are described below. 
     In a magnetic sensor  110   a  as shown in  FIG. 6B , the first corresponding one-portion  21   e  is electrically connected with the second corresponding other-portion  22   f.  The first corresponding other-portion  21   f  is electrically connected with the fourth corresponding one-portion  24   e.  The third corresponding one-portion  23   e  is electrically connected with the fourth corresponding other-portion  24   f.  The third corresponding other-portion  23   f  is electrically connected with the second corresponding one-portion  22   e.    
     In the magnetic sensor  110   a,  the first current circuit  71  is configured to supply the first current I 1  that includes the alternating current between a seventh connection point CP 7  and an eighth connection point CP 8 , in which the seventh connection point CP 7  is between the first corresponding one-portion  21   e  and the second corresponding other-portion  22   f,  and the eighth connection point CP 8  is between the third corresponding one-portion  23   e  and the fourth corresponding other-portion  24   f.    
     At one time (the first time) in the magnetic sensor  110   a,  the first current I 1  has the orientation from the first corresponding other-portion  21   f  toward the first corresponding one-portion  21   e,  the orientation from the second corresponding one-portion  22   e  toward the second corresponding other-portion  22   f,  the orientation from the third corresponding one-portion  23   e  toward the third corresponding other-portion  23   f,  and the orientation from the fourth corresponding other-portion  24   f  toward the fourth corresponding one-portion  24   e.  A configuration such as that shown in  FIG. 6B  may be combined with the configuration of  FIG. 5 . 
     In the example shown in  FIG. 6B , the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series is provided. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. 
     In a magnetic sensor  110   b  as shown in  FIG. 6C , the first corresponding other-portion  21   f  is electrically connected with the fourth corresponding one-portion  24   e.  The third corresponding other-portion  23   f  is electrically connected with the second corresponding one-portion  22   e.  The second corresponding other-portion  22   f  is electrically connected with the fourth corresponding other-portion  24   f.    
     In the magnetic sensor  110   b,  the first current circuit  71  is configured to supply the first current I 1  that includes the alternating current between the first corresponding one-portion  21   e  and the third corresponding one-portion  23   e.    
     At one time (the first time) in the magnetic sensor  110   b,  the first current I 1  has the orientation from the first corresponding other-portion  21   f  toward the first corresponding one-portion  21   e,  the orientation from the second corresponding one-portion  22   e  toward the second corresponding other-portion  22   f,  the orientation from the third corresponding one-portion  23   e  toward the third corresponding other-portion  23   f,  and the orientation from the fourth corresponding other-portion  24   f  toward the fourth corresponding one-portion  24   e.  A configuration such as that shown in  FIG. 6C  may be combined with the configuration of  FIG. 5 . 
     In the example shown in  FIG. 6C , the first to fourth corresponding portions  21  to  24  are electrically connected in series to each other. 
     In a magnetic sensor  110   c  as shown in  FIG. 6D , the first corresponding one-portion  21   e  is electrically connected with the second corresponding other-portion  22   f,  the third corresponding other-portion  23   f,  and the fourth corresponding one-portion  24   e.  The first corresponding other-portion  21   f  is electrically connected with the second corresponding one-portion  22   e,  the third corresponding one-portion  23   e,  and the fourth corresponding other-portion  24   f.    
     In the magnetic sensor  110   c,  the first current circuit  71  is configured to supply the first current I 1  that includes the alternating current between a ninth connection point CP 9  and a tenth connection point CP 10 , in which the ninth connection point CP 9  is between the first corresponding one-portion  21   e,  the second corresponding other-portion  22   f,  the third corresponding other-portion  23   f,  and the fourth corresponding one-portion  24   e,  and the tenth connection point CP 10  is between the first corresponding other-portion  21   f,  the second corresponding one-portion  22   e,  the third corresponding one-portion  23   e,  and the fourth corresponding other-portion  24   f.    
     At one time (the first time) in the magnetic sensor  110   c,  the first current I 1  has the orientation from the first corresponding other-portion  21   f  toward the first corresponding one-portion  21   e,  the orientation from the second corresponding one-portion  22   e  toward the second corresponding other-portion  22   f,  the orientation from the third corresponding one-portion  23   e  toward the third corresponding other-portion  23   f,  and the orientation from the fourth corresponding other-portion  24   f  toward the fourth corresponding one-portion  24   e.  A configuration such as that shown in  FIG. 6D  may be combined with the configuration of  FIG. 5 . 
     In the example shown in  FIG. 6D , the first to fourth corresponding portions  21  to  24  are electrically connected in parallel to each other. 
     The element current circuit  75 , the detection circuit  73 , and the first current circuit  71  may be included in a control circuit part  70 . 
     In the example shown in  FIG. 5 , the magnetic element that is electrically connected in series with the first magnetic element  11 E is taken to be the second magnetic element  12 E. The magnetic element that is electrically connected in series with the third magnetic element  13 E is taken to be the fourth magnetic element  14 E. The set that includes the first and second magnetic elements  11 E and  12 E is electrically connected in parallel with the set that includes the third and fourth magnetic elements  13 E and  14 E. Various modifications of the spatial arrangement of the first to fourth magnetic elements  11 E to  14 E are possible. 
     The portions of the circuits illustrated in  FIGS. 6A to 6D  may be combined. For example, the first corresponding portion  21  and the third corresponding portion  24  that are connected in series may be connected with the first current circuit  71  in parallel with the second and third corresponding portions  22  and  23 . 
     Examples of the spatial arrangement of the first to fourth magnetic elements  11 E to  14 E will now be described. The following are examples in which the first to fourth magnetic elements  11 E to  14 E are arranged in this order along the second direction (e.g., the X-axis direction). In the following example, the magnetic element that is electrically connected in series with the first magnetic element  11 E may be one of the second magnetic element  12 E, the third magnetic element  13 E, or the fourth magnetic element  14 E. The magnetic element that is electrically connected in series with the third magnetic element  13 E may be one of the first magnetic element  11 E, the second magnetic element  12 E, or the fourth magnetic element  14 E. 
       FIGS. 7A to 7C ,  FIGS. 8A to 8C ,  FIGS. 9A to 9C ,  FIGS. 10A to 10C ,  FIGS. 11A to 11C , and  FIGS. 12A to 12C  are schematic views illustrating the magnetic sensor according to the first embodiment. 
       FIGS. 7A, 8A, 9A, 10A, 11A, and 12A  illustrate first to sixth element configurations CF 1  to CF 6  that relate to the connection of the first to fourth magnetic elements  11 E to  14 E.  FIGS. 7B, 7C, 8B, 8C, 9B, 9C, 10B, 10C, 11B, 11C, 12B, and 12C  illustrate first to twelfth corresponding portion configurations CG 1  to CG 12  that relate to the connection of the first to fourth corresponding portions  21  to  24 . 
     In the first element configuration CF 1  as shown in  FIG. 7A , the multiple magnetic elements are arranged along the X-axis direction in the order of the first magnetic element  11 E, the third magnetic element  13 E, the second magnetic element  12 E, and the fourth magnetic element  14 E. 
     In the first corresponding portion configuration CG 1  as shown in  FIG. 7B , the first corresponding one-portion  21   e  is connected with the first current circuit  71 . The first corresponding other-portion  21   f  is connected with the second corresponding one-portion  22   e.  The second corresponding other-portion  22   f  is connected with the fourth corresponding other-portion  24   f.  The fourth corresponding one-portion  24   e  is connected with the third corresponding other-portion  23   f.  The third corresponding one-portion  23   e  is connected with the first current circuit  71 . 
     In the first corresponding portion configuration CG 1 , the first to fourth corresponding portions  21  to  24  are electrically connected in series. In the first corresponding portion configuration CG 1 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     In the second corresponding portion configuration CG 2  as shown in  FIG. 7C , the first corresponding other-portion  21   f  is connected with the first current circuit  71 . The first corresponding one-portion  21   e  is connected with the fourth corresponding other-portion  24   f.  The fourth corresponding one-portion  24   e  is connected with the first current circuit  71 . The third corresponding one-portion  23   e  is connected with the first current circuit  71 . The third corresponding other-portion  23   f  is connected with the second corresponding one-portion  22   e.  The second corresponding other-portion  22   f  is connected with the first current circuit  71 . 
     The second corresponding portion configuration CG 2  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the second corresponding portion configuration CG 2 , the first current I 1  has the orientation described with reference to  FIG. 6B . 
     The first element configuration CF 1  may be combined with one of the first corresponding portion configuration CG 1  or the second corresponding portion configuration CG 2 . 
     In the second element configuration CF 2  as shown in  FIG. 8A , the multiple magnetic elements are arranged along the X-axis direction in the order of the first magnetic element  11 E, the second magnetic element  12 E, the third magnetic element  13 E, and the fourth magnetic element  14 E. 
     In the third corresponding portion configuration CG 3  as shown in  FIG. 8B , the first to fourth corresponding portions  21  to are electrically connected in series. In the third corresponding portion configuration CG 3 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     As shown in  FIG. 8C , the fourth corresponding portion configuration CG 4  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the fourth corresponding portion configuration CG 4 , the first current I 1  has the orientation described with reference to  FIG. 6B . The second element configuration CF 2  may be combined with one of the third corresponding portion configuration CG 3  or the fourth corresponding portion configuration CG 4 . 
     In the third element configuration CF 3  as shown in  FIG. 9A , the multiple magnetic elements are arranged along the X-axis direction in the order of the third magnetic element  13 E, the fourth magnetic element  14 E, the second magnetic element  12 E, and the first magnetic element  11 E. 
     In the fifth corresponding portion configuration CG 5  as shown in  FIG. 9B , the first to fourth corresponding portions  21  to are electrically connected in series. In the fifth corresponding portion configuration CG 5 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     As shown in  FIG. 9C , the sixth corresponding portion configuration CG 6  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the sixth corresponding portion configuration CG 6 , the first current I 1  has the orientation described with reference to  FIG. 6B . The third element configuration CF 3  may be combined with one of the fifth corresponding portion configuration CG 5  or the sixth corresponding portion configuration CG 6 . 
     In the fourth element configuration CF 4  as shown in  FIG. 10A , the multiple magnetic elements are arranged along the X-axis direction in the order of the first magnetic element  11 E, the third magnetic element  13 E, the fourth magnetic element  14 E, and the second magnetic element  12 E. 
     In the seventh corresponding portion configuration CG 7  as shown in  FIG. 10B , the first to fourth corresponding portions  21  to  24  are electrically connected in series. In the seventh corresponding portion configuration CG 7 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     As shown in  FIG. 10C , the eighth corresponding portion configuration CG 8  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the eighth corresponding portion configuration CG 8 , the first current I 1  has the orientation described with reference to  FIG. 6B . The fourth element configuration CF 4  may be combined with one of the seventh corresponding portion configuration CG 7  or the eighth corresponding portion configuration CG 8 . 
     In the fifth element configuration CF 5  as shown in  FIG. 11A , the multiple magnetic elements are arranged along the X-axis direction in the order of the first magnetic element  11 E, the fourth magnetic element  14 E, the third magnetic element  13 E, and the second magnetic element  12 E. 
     In the ninth corresponding portion configuration CG 9  as shown in  FIG. 11B , the first to fourth corresponding portions  21  to  24  are electrically connected in series. In the ninth corresponding portion configuration CG 9 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     As shown in  FIG. 11C , the tenth corresponding portion configuration CG 10  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the tenth corresponding portion configuration CG 10 , the first current I 1  has the orientation described with reference to  FIG. 6B . The fifth element configuration CF 5  may be combined with one of the ninth corresponding portion configuration CG 9  or the tenth corresponding portion configuration CG 10 . 
     In the sixth element configuration CF 6  as shown in  FIG. 12A , the multiple magnetic elements are arranged along the X-axis direction in the order of the fourth magnetic element  14 E, the first magnetic element  11 E, the third magnetic element  13 E, and the second magnetic element  12 E. 
     In the eleventh corresponding portion configuration CG 11  as shown in  FIG. 12B , the first to fourth corresponding portions  21  to  24  are electrically connected in series. In the eleventh corresponding portion configuration CG 11 , the first current I 1  has the orientation described with reference to  FIG. 6C . 
     As shown in  FIG. 12C , the twelfth corresponding portion configuration CG 12  includes the first circuit that includes the first and fourth corresponding portions  21  and  24  that are connected in series. The second circuit that includes the second and third corresponding portions  22  and  23  that are connected in series is provided. The first circuit and the second circuit are electrically connected in parallel. In the twelfth corresponding portion configuration CG 12 , the first current I 1  has the orientation described with reference to  FIG. 6B . The sixth element configuration CF 6  may be combined with one of the eleventh corresponding portion configuration CG 11  or the twelfth corresponding portion configuration CG 12 . 
     In the first to sixth element configurations CF 1  to CF 6 , the element current Id has the orientation described with reference to  FIG. 5 . In other words, the element current Id has the orientation from the one end portion  11 Ee toward the other end portion  11 Ef, the orientation from the one end portion  12 Ee toward the other end portion  12 Ef, the orientation from the one end portion  13 Ee toward the other end portion  13 Ef, and the orientation from the one end portion  14 Ee toward the other end portion  14 Ef. 
     As shown in  FIGS. 7B, 7C, 8B, 8C, 9B, 9C, 10B, 10C, 11B, 11C, 12B, and 12C , a portion  21 x of the conductive member  20  overlaps the magnetic member  51  in the first direction (the Y-axis direction). For example, the portion  21 x of the conductive member  20  is between the base body  55  and the magnetic member  51  in the first direction (the Y-axis direction). 
     For example, the first connection member  15   a  is electrically connected with one of the other end portion  11 Ef or the one end portion  11 Ee of the first magnetic element  11 E. The second connection member  15   b  is electrically connected with the other of the other end portion  11 Ef or the one end portion  11 Ee of the first magnetic element  11 E. As shown in  FIGS. 7A, 8A, 9A, 10A, 11A, and 12A , for example, the first connection member  15   a  overlaps the magnetic member  51  in the Y-axis direction. For example, the second connection member  15   b  does not overlap the magnetic member  51  in the Y-axis direction. 
     For example, the electrical resistances of the first to fourth magnetic elements  11 E to  14 E have substantially even-function characteristics with respect to the external magnetic field. For example, the electrical resistances have substantially even-function characteristics with respect to the current flowing through the conductive member  20  (the first to fourth corresponding portions  21  to  24 ). By applying an alternating magnetic by the first current I 1  that includes the alternating current to the magnetic elements that have even-function characteristics, detection with higher sensitivity is possible as described below. 
     An example of the change of the electrical resistance of a magnetic element (the first magnetic element  11 E) when a current flows in the conductive member  20  will now be described. The electrical resistance of the first magnetic element  11 E will now be described. The following description is applicable to the second to fourth magnetic elements  12 E to  14 E. 
       FIGS. 13A and 13B  are schematic views illustrating characteristics of the magnetic sensor according to the first embodiment. 
     In these figures, the horizontal axis corresponds to the value of the current (e.g., the first current I 1 ) flowing in the conductive member  20  (e.g., the first corresponding portion  21 ). The vertical axis is an electrical resistance Rx of the first magnetic element  11 E. According to the embodiment as shown in  FIGS. 13A and 13B , the electrical resistance Rx has an even-function characteristic with respect to the change of the current (the first current I 1 ). 
     For example, the electrical resistance Rx of the first magnetic element  11 E has a first value R 1  when a first-value current Ia 1  is supplied to the first corresponding portion  21 . The electrical resistance Rx has a second value R 2  when a second-value current Ia 2  is supplied to the first corresponding portion  21 . The electrical resistance Rx has a third value R 3  when a third-value current Ia 3  is supplied to the first corresponding portion  21 . The absolute value of the first-value current Ia 1  is less than the absolute value of the second-value current Ia 2  and less than the absolute value of the third-value current Ia 3 . For example, the first-value current Ia 1  may be substantially  0 . The orientation of the second-value current Ia 2  is opposite to the orientation of the third-value current Ia 3 . 
     In the example of  FIG. 13A , the first value R 1  is less than the second value R 2  and less than the third value R 3 . In the example of  FIG. 13A , the electrical resistance Rx has a “valley-like” characteristic. The first value R 1  is, for example, the minimum value of the electrical resistance. In the example of  FIG. 13B , the first value R 1  is greater than the second value R 2  and greater than the third value R 3 . In the example of  FIG. 13B , the electrical resistance Rx has a “hill-like” characteristic. The first value R 1  is, for example, the maximum value of the electrical resistance. 
     For example, when the external magnetic field is substantially 0, the magnetization of the first magnetic layer  11  and the magnetization of the first counter magnetic layer  11   o  have “parallel alignment”; for example, a “valley-like” characteristic is obtained due to the effect of interlayer magnetic coupling. In such a case, for example, the thickness of the first nonmagnetic layer  11   n  is not less than 2.5 nm. For example, when the external magnetic field is substantially 0, the magnetization of the first magnetic layer  11  and the magnetization of the first counter magnetic layer  11   o  have “antiparallel alignment”; for example, a “hill-like” characteristic is obtained due to the effect of interlayer magnetic coupling. In such a case, the thickness of the first nonmagnetic layer  11   n  is, for example, not less than 1.9 nm and not more than 2.1 nm. 
     For example, when a current does not flow in the first corresponding portion  21 , the electrical resistance Rx has a fourth value R 4 . For example, the first value R 1  is substantially equal to the fourth value R 4  when the current does not flow. For example, the ratio of the absolute value of the difference between the first value R 1  and the fourth value R 4  to the fourth value R 4  is not more than 0.01. The ratio may be not more than 0.001. A substantially even-function characteristic with respect to the positive and negative current is obtained. 
     Such a relationship between the first current I 1  and the electrical resistance Rx is caused since the magnetic field from the first current I 1  is applied to the first magnetic element  11 E and the electrical resistance Rx of the first magnetic element  11 E is changed according to the intensity of the magnetic field. 
     When an external magnetic field is applied to the first magnetic element  11 E, the electrical resistance Rx also shows an even-function characteristic as shown in  FIG. 13A  or  FIG. 13B . The external magnetic field includes, for example, a component along the Z-axis direction. 
       FIGS. 14A and 14B  are schematic views illustrating characteristics of the magnetic sensor according to the first embodiment. 
     In these figures, the horizontal axis is the intensity of an external magnetic field Hex that is applied to the first magnetic element  11 E. The vertical axis is the electrical resistance Rx of the first magnetic element  11 E. These figures correspond to the R-H characteristic. As shown in  FIGS. 14A and 14B , the electrical resistance Rx has an even-function characteristic with respect to the magnetic field (the external magnetic field Hex, e.g., a magnetic field in the Z-axis direction) that is applied to the first magnetic element  11 E. 
     As shown in  FIGS. 14A and 14B , the electrical resistance Rx of the first magnetic element  11 E has the first value R 1  when a first magnetic field Hex 1  is applied to the first magnetic element  11 E. The electrical resistance Rx has the second value R 2  when a second magnetic field Hex 2  is applied to the first magnetic element  11 E. The electrical resistance Rx has the third value R 3  when a third magnetic field Hex 3  is applied to the first magnetic element  11 E. The absolute value of the first magnetic field Hex 1  is less than the absolute value of the second magnetic field Hex 2  and less than the absolute value of the third magnetic field Hex 3 . The orientation of the second magnetic field Hex 2  is opposite to the orientation of the third magnetic field Hex 3 . 
     In the example of  FIG. 14A , the first value R 1  is less than the second value R 2  and less than the third value R 3 . In the example of  FIG. 14B , the first value R 1  is greater than the second value R 2  and greater than the third value R 3 . For example, the electrical resistance Rx has the fourth value R 4  when the external magnetic field is not applied to the first magnetic element  11 E. The first value R 1  is substantially equal to the fourth value R 4  when the external magnetic field is not applied. For example, the ratio of the absolute value of the difference between the first value R 1  and the fourth value R 4  to the fourth value R 4  is not more than 0.01. The ratio may be not more than 0.001. A substantially even-function characteristic is obtained for the positive and negative external magnetic fields. 
     By utilizing such an even-function characteristic, highly-sensitive detection is possible as follows. 
     An example will now be described in which the first current I 1  is an alternating current and substantially does not include a direct current component. The first current I 1  (the alternating current) is supplied to the first corresponding portion  21 ; and an alternating magnetic field due to the alternating current is applied to the first magnetic element  11 E. An example of the change of the electrical resistance Rx at this time will now be described. 
       FIGS. 15A to 15C  are graphs illustrating characteristics of the magnetic sensor according to the first embodiment. 
       FIG. 15A  shows characteristics when a signal magnetic field Hsig (an external magnetic field) applied to the first magnetic element  11 E is 0.  FIG. 15B  shows characteristics when the signal magnetic field Hsig is positive.  FIG. 15C  shows characteristics when the signal magnetic field Hsig is negative. These figures show the relationship between a magnetic field H and a resistance R (corresponding to the electrical resistance Rx). 
     As shown in  FIG. 15A , when the signal magnetic field Hsig is 0, the resistance R has a characteristic that is symmetric with respect to the positive and negative magnetic field H. When an alternating magnetic field Hac is zero, the resistance R is a low resistance Ro. For example, the magnetization of the free magnetic layer (a first magnetic layer  11  and/or a first counter magnetic layer  11   o, ) is rotated substantially identically to the positive and negative magnetic field H. Therefore, a symmetric resistance change is obtained. The change of the resistance R with respect to the alternating magnetic field Hac has the same value between the positive and negative polarities. The period of the change of the resistance R is 1/2 times the period of the alternating magnetic field Hac. The change of the resistance R substantially does not include the frequency component of the alternating magnetic field Hac. 
     As shown in  FIG. 15B , the characteristic of the resistance R shifts to the positive magnetic field H side when a positive signal magnetic field Hsig is applied. For example, the resistance R becomes high for the alternating magnetic field Hac on the positive side. The resistance R becomes low for the alternating magnetic field Hac on the negative side. 
     As shown in  FIG. 15C , the characteristic of the resistance R shifts to the negative magnetic field H side when a negative signal magnetic field Hsig is applied. For example, the resistance R becomes low for the alternating magnetic field Hac on the positive side. The resistance R becomes high for the alternating magnetic field Hac on the negative side. 
     When a signal magnetic field Hsig with non-zero magnitude is applied, the deviation in the resistance R is generated. The deviation is different for the positive and negative portion of the alternating magnetic field Hac. The period of the deviation is equal to the period of the alternating magnetic field Hac. An output voltage which has the same frequency component as that of Hac corresponding to the deviation. An output voltage that has a frequency component of Hac corresponding to the signal magnetic field Hsig. 
     The characteristics described above are obtained in the case where the signal magnetic field Hsig does not temporally change. The case where the signal magnetic field Hsig temporally changes is as follows. The frequency of the signal magnetic field Hsig is taken as a signal frequency fsig. The frequency of the alternating magnetic field Hac is taken as an alternating current frequency fac. In such a case, an output that corresponds to the signal magnetic field Hsig is generated at the frequency of fac±fsig. 
     In the case where the signal magnetic field Hsig temporally changes, the signal frequency fsig is, for example, not more than 1 kHz. On the other hand, the alternating current frequency fac is sufficiently greater than the signal frequency fsig. For example, the alternating current frequency fac is not less than 10 times the signal frequency fsig. 
     For example, the signal magnetic field Hsig can be detected with high accuracy by extracting an output voltage having the same period (frequency) component (alternating current frequency component) as the period (the frequency) of the alternating magnetic field Hac. In the magnetic sensor  112  according to the embodiment, the external magnetic field Hex (the signal magnetic field Hsig) can be detected with high sensitivity. According to the embodiment, the external magnetic field Hex (the signal magnetic field Hsig) and the alternating magnetic field Hac due to the first current I 1  can be efficiently applied to the first magnetic element  11 E by the magnetic member  51 . High sensitivity is obtained. 
       FIGS. 16A and 16B  are schematic views illustrating a magnetic sensor according to the first embodiment. 
     In the magnetic sensor  115  according to the embodiment as shown in  FIG. 16A , the element part  10 U includes the first magnetic element  11 E, the second magnetic element  12 E, a first resistance element  11 R, and a second resistance element  12 R. Otherwise, the configuration of the magnetic sensor  115  may be, for example, the same as those of the magnetic sensor  110 , etc. For example, the magnetic sensor  115  also includes the base body  55 , the magnetic member  51 , and the element part  10 U. 
     In the magnetic sensor  115 , the one end portion  11 Ee of the first magnetic element  11 E is electrically connected with one end portion  11 Re of the first resistance element  11 R. The other end portion  11 Ef of the first magnetic element  11 E is electrically connected with the one end portion  12 Ee of the second magnetic element  12 E. Another end portion  11 Rf of the first resistance element  11 R is electrically connected with one end portion  12 Re of the second resistance element  12 R. The other end portion  12 Ef of the second magnetic element  12 E is electrically connected with another end portion  12 Rf of the second resistance element  12 R. 
     The element current circuit  75  is configured to supply the element current Id between the first connection point CP 1  and the second connection point CP 2 , in which the first connection point CP 1  is between the one end portion  11 Ee of the first magnetic element  11 E and the one end portion  11 Re of the first resistance element  11 R, and the second connection point CP 2  is between the other end portion  12 Ef of the second magnetic element  12 E and the other end portion  12 Rf of the second resistance element  12 R. 
     The detection circuit  73  is configured to detect the change of the potential between the third connection point CP 3  and the fourth connection point CP 4 , in which the third connection point CP 3  is between the other end portion  11 Ef of the first magnetic element  11 E and the one end portion  12 Ee of the second magnetic element  12 E, and the fourth connection point CP 4  is between the other end portion  11 Rf of the first resistance element  11 R and the one end portion  12 Re of the second resistance element  12 R. 
     As shown in  FIG. 16B , the first corresponding other-portion  21   f  is electrically connected with the second corresponding one-portion  22   e.  The first corresponding one-portion  21   e  is electrically connected with the second corresponding other-portion  22   f.  The first current circuit  71  is configured to supply the first current I 1  that includes the alternating current between the fifth connection point CP 5  and the sixth connection point CP 6 , in which the fifth connection point CP 5  is between the first corresponding other-portion  21   f  and the second corresponding one-portion  22   e,  and the sixth connection point CP 6  is between the first corresponding one-portion  21   e  and the second corresponding other-portion  22   f.    
     Second Embodiment 
     A second embodiment relates to an inspection device. As described below, the inspection device may include a diagnostic device. 
       FIG. 17  is a schematic view illustrating the inspection device according to the second embodiment. 
     As shown in  FIG. 17 , the inspection device  550  according to the embodiment includes a processor  78  and the magnetic sensor (in the example of  FIG. 17 , the magnetic sensor  110 ) according to the embodiment. The processor  78  processes an output signal SigX obtained from the magnetic sensor  110 . In the example, the processor  78  includes a sensor control circuit part  75   c,  a first lock-in amplifier  75   a,  and a second lock-in amplifier  75   b.  For example, the first current circuit  71  is controlled by the sensor control circuit part  75   c;  and the first current I 1  that includes the alternating current component is supplied from the first current circuit  71  to a sensor part  10 S. The frequency of the alternating current component of the first current I 1  is, for example, not more than 100 kHz. The element current Id is supplied from the element current circuit  75  to the sensor part  10 S. The sensor part  10 S includes, for example, the element part  10 U. The change of the potential of the sensor part  10 S is detected by the detection circuit  73 . For example, the output of the detection circuit  73  is the output signal SigX. 
     In the example, the inspection device  550  includes a magnetic field application part  76 A. The magnetic field application part  76 A is configured to apply a magnetic field to the detection object  80 . The detection object  80  is, for example, the inspection object. The detection object  80  includes at least the inspection conductive member  80   c  such as a metal, etc. For example, an eddy current is generated in the inspection conductive member  80   c  when the magnetic field due to the magnetic field application part  76 A is applied to the inspection conductive member  80   c.  The state of the eddy current changes when there is a flaw or the like in the inspection conductive member  80   c.  The state (e.g., the flaw, etc.) of the inspection conductive member  80   c  can be inspected by the magnetic sensor (e.g., the magnetic sensor  110 , etc.) detecting the magnetic field due to the eddy current. The magnetic field application part  76 A is, for example, an eddy current generator. 
     In the example, the magnetic field application part  76 A includes an application control circuit part  76   a,  a drive amplifier  76   b,  and a coil  76   c.  A current is supplied to the drive amplifier  76   b  by the control by the application control circuit part  76   a.  The current is, for example, an alternating current. The frequency of the current is, for example, an eddy current excitation frequency. The eddy current excitation frequency is, for example, not less than 10 Hz and not more than 100 kHz. The eddy current excitation frequency may be, for example, less than 100 kHz. 
     For example, information (which may be, for example, a signal) that relates to the frequency of the alternating current component of the first current I 1  is supplied from the sensor control circuit part  75   c  to the first lock-in amplifier  75   a  as a reference signal. The output of the first lock-in amplifier  75   a  is supplied to the second lock-in amplifier  75   b.  Information (which may be, for example, a signal) that relates to the eddy current excitation frequency is supplied from the application control circuit part  76   a  to the second lock-in amplifier  75   b  as a reference signal. The second lock-in amplifier  75   b  is configured to output a signal component corresponding to the eddy current excitation frequency. 
     Thus, for example, the processor  78  includes the first lock-in amplifier  75   a.  The output signal SigX that is obtained from the magnetic sensor  110  and a signal SigR 1  that corresponds to the frequency of the alternating current component included in the first current I 1  are input to the first lock-in amplifier  75   a.  The first lock-in amplifier  75   a  is configured to output an output signal SigX 1  that uses the signal SigR 1  corresponding to the frequency of the alternating current component included in the first current I 1  as a reference wave (a reference signal). By providing the first lock-in amplifier  75   a,  it is possible to suppress noise and detect with high sensitivity. 
     The processor  78  may further include the second lock-in amplifier  75   b.  The output signal SigX 1  of the first lock-in amplifier  75   a  and a signal SigR 2  that corresponds to the frequency (the eddy current excitation frequency) of the supply signal (in the example, the magnetic field due to the magnetic field application part  76 A) supplied toward the detection object  80  (the inspection object) are input to the second lock-in amplifier  75   b.  The second lock-in amplifier  75   b  is configured to output an output signal SigX 2  that uses the signal SigR 2  corresponding to the frequency of the supply signal supplied toward the detection object  80  (the inspection object) as a reference signal. By providing the second lock-in amplifier  75   b,  it is possible to further suppress noise and detect with even higher sensitivity. 
     A defect such as a flaw or the like of the inspection conductive member  80   c  of the detection object  80  can be inspected by the inspection device  550 . 
       FIG. 18  is a schematic view illustrating an inspection device according to the second embodiment. 
     As shown in  FIG. 18 , the inspection device  551  according to the embodiment includes the processor  78  and the magnetic sensor (e.g., the magnetic sensor  110 ) according to the embodiment. The configurations of the magnetic sensor and the processor  78  of the inspection device  551  may be similar to those of the inspection device  550 . In the example, the inspection device  551  includes a detection object driver  76 B. The detection object driver  76 B is configured to supply a current to the inspection conductive member  80   c  included in the detection object  80 . The inspection conductive member  80   c  is, for example, wiring included in the detection object  80 . A magnetic field that is due to a current  80   i  flowing in the inspection conductive member  80   c  is detected by the magnetic sensor  110 . The inspection conductive member  80   c  can be inspected based on an abnormality due to the detection result of the magnetic sensor  110 . The detection object  80  may be, for example, an electronic device such as a semiconductor device, etc. The detection object  80  may be, for example, a battery, etc. 
     In the example, the detection object driver  76 B includes the application control circuit part  76   a  and the drive amplifier  76   b.  The drive amplifier  76   b  is controlled by the application control circuit part  76   a;  and a current is supplied from the drive amplifier  76   b  to the inspection conductive member  80   c.  The current is, for example, an alternating current. For example, the alternating current is supplied to the inspection conductive member  80   c.  The frequency of the alternating current is, for example, not less than 10 Hz and not more than 100 kHz. The frequency may be, for example, less than 100 kHz. In the example as well, for example, by providing the first lock-in amplifier  75   a  and the second lock-in amplifier  75   b,  it is possible to suppress noise and detect with high sensitivity. In one example of the inspection device  551 , multiple magnetic sensors (e.g., the multiple magnetic sensors  110 ) may be provided. The multiple magnetic sensors are, for example, a sensor array. The inspection conductive member  80   c  can be inspected in a short period of time by the sensor array. In one example of the inspection device  551 , the inspection conductive member  80   c  may be inspected by scanning the magnetic sensor (e.g., the magnetic sensor  110 ). 
       FIG. 19  is a schematic perspective view showing an inspection device according to the second embodiment. 
     As shown in  FIG. 19 , the inspection device  710  according to the embodiment includes a magnetic sensor  150   a  and a processor  770 . The magnetic sensor  150   a  may be any magnetic sensor according to the first or second embodiment or a modification of the magnetic sensor. The processor  770  processes an output signal obtained from the magnetic sensor  150   a.  The processor  770  may perform a comparison between a reference value and the signal obtained from the magnetic sensor  150   a,  etc. The processor  770  is configured to output an inspection result based on the processing result. 
     For example, an inspection object  680  is inspected by the inspection device  710 . The inspection object  680  is, for example, an electronic device (including a semiconductor circuit, etc.). The inspection object  680  may be, for example, a battery  610 , etc. 
     For example, the magnetic sensor  150   a  according to the embodiment may be used together with the battery  610 . For example, a battery system  600  includes the battery  610  and the magnetic sensor  150   a.  The magnetic sensor  150   a  can detect a magnetic field generated by a current flowing in the battery  610 . 
       FIG. 20  is a schematic plan view showing the inspection device according to the second embodiment. 
     As shown in  FIG. 20 , the magnetic sensor  150   a  includes, for example, multiple magnetic sensors according to the embodiment. In the example, the magnetic sensor  150   a  includes multiple magnetic sensors (e.g., the magnetic sensor  110 , etc.). For example, the multiple magnetic sensors are arranged along two directions. For example, the multiple magnetic sensors  110  are located on a base body. 
     The magnetic sensor  150   a  can detect a magnetic field generated by a current flowing in the inspection object  680  (which may be, for example, the battery  610 ). For example, an abnormal current flows in the battery  610  when the battery  610  approaches an abnormal state. The change of the state of the battery  610  can be known by the magnetic sensor  150   a  detecting the abnormal current. For example, the entire battery  610  can be inspected in a short period of time by moving the sensor array in two directions while the magnetic sensor  150   a  is placed proximate to the battery  610 . The magnetic sensor  150   a  may be used to inspect the battery  610  in the manufacturing process of the battery  610 . 
     For example, the magnetic sensor according to the embodiment is applicable to the inspection device  710  such as a diagnostic device, etc.  FIG. 21  is a schematic view showing the magnetic sensor and the inspection device according to the second embodiment. 
     As shown in  FIG. 21 , the diagnostic device  500  is an example of the inspection device  710  and includes the magnetic sensor  150 . The magnetic sensor  150  includes the magnetic sensor described in reference to the first and second embodiments and modifications of the magnetic sensor. 
     In the diagnostic device  500 , the magnetic sensor  150  is, for example, a magnetoencephalography device. The magnetoencephalography device detects a magnetic field generated by cranial nerves. When the magnetic sensor  150  is included in a magnetoencephalography device, the size of the magnetic element included in the magnetic sensor  150  is, for example, not less than 1 mm but less than 10 mm. The size is, for example, the length including the MFC. 
     As shown in  FIG. 21 , the magnetic sensor  150  (the magnetoencephalography device) is mounted to, for example, the head of a human body. The magnetic sensor  150  (the magnetoencephalography device) includes a sensor part  301 . The magnetic sensor  150  (the magnetoencephalography device) may include multiple sensor parts  301 . The number of the multiple sensor parts  301  is, for example, about 100 (e.g., not less than 50 and not more than 150). The multiple sensor parts  301  are provided on a flexible base body  302 . 
     The magnetic sensor  150  may include, for example, a circuit for differential detection, etc. The magnetic sensor  150  may include a sensor other than a magnetic sensor (e.g., a potential terminal, an acceleration sensor, etc.). 
     The size of the magnetic sensor  150  is small compared to the size of a conventional SQUID magnetic sensor. Therefore, the mounting of the multiple sensor parts  301  is easy. The mounting of the multiple sensor parts  301  and the other circuits is easy. The multiple sensor parts  301  and the other sensors can be easily mounted together. 
     The base body  302  may include, for example, an elastic body such as a silicone resin, etc. For example, the multiple sensor parts  301  are linked to each other and provided in the base body  302 . For example, the base body  302  can be closely adhered to the head. 
     An input/output cord  303  of the sensor part  301  is connected with a sensor driver  506  and a signal input/output part  504  of the diagnostic device  500 . A magnetic field measurement is performed in the sensor part  301  based on electrical power from the sensor driver  506  and a control signal from the signal input/output part  504 . The result is input to the signal input/output part  504 . The signal that is obtained by the signal input/output part  504  is supplied to a signal processor  508 . Processing such as, for example, the removal of noise, filtering, amplification, signal calculation, etc., are performed in the signal processor  508 . The signal that is processed by the signal processor  508  is supplied to a signal analyzer  510 . For example, the signal analyzer  510  extracts a designated signal for magnetoencephalography. For example, signal analysis to match the signal phases is performed in the signal analyzer  510 . 
     The output of the signal analyzer  510  (the data for which the signal analysis is finished) is supplied to a data processor  512 . Data analysis is performed in the data processor  512 . It is possible to include image data such as, for example, MRI (Magnetic Resonance Imaging), etc., in the data analysis. It is possible to include, for example, scalp potential information such as an EEG (Electroencephalogram), etc., in the data analysis. For example, a data part  514  of the MRI, the EEG, etc., is connected with the data processor  512 . For example, nerve firing point analysis, inverse analysis, or the like is performed by the data analysis. 
     For example, the result of the data analysis is supplied to an imaging diagnostic part  516 . Imaging is performed by the imaging diagnostic part  516 . The diagnosis is supported by the imaging. 
     For example, the series of operations described above is controlled by a control mechanism  502 . For example, necessary data such as preliminary signal data, metadata partway through the data processing, or the like is stored in a data server. The data server and the control mechanism may be integrated. 
     The diagnostic device  500  according to the embodiment includes the magnetic sensor  150 , and a processor that processes the output signal obtained from the magnetic sensor  150 . The processor includes, for example, at least one of the signal processor  508  or the data processor  512 . The processor includes, for example, a computer, etc. 
     In the magnetic sensor  150  shown in  FIG. 21 , the sensor part  301  is mounted to the head of a human body. The sensor part  301  may be mounted to the chest of the human body. Magnetocardiography is possible thereby. For example, the sensor part  301  may be mounted to the abdomen of a pregnant woman. Palmoscopy of the fetus can be performed thereby. 
     It is favorable for the magnetic sensor device including the participant to be mounted inside a shielded room. For example, the effects of geomagnetism or magnetic noise can be suppressed thereby. 
     For example, a mechanism may be provided to locally shield the sensor part  301  or the measurement section of the human body. For example, a shield mechanism may be provided in the sensor part  301 . For example, the signal analysis or the data processing may be effectively shielded. 
     According to the embodiment, the base body  302  may be flexible or may be substantially not flexible. In the example shown in  FIG. 21 , the base body  302  is a continuous membrane that is patterned into a hat-like configuration. The base body  302  may have a net configuration. For example, a good fit is obtained thereby. For example, the adhesion of the base body  302  to the human body is improved. The base body  302  may have a hard helmet-like configuration. 
       FIG. 22  is a schematic view showing the inspection device according to the second embodiment. 
       FIG. 22  is an example of a magnetocardiography device. In the example shown in  FIG. 22 , the sensor part  301  is provided on a hard base body  305  having a flat plate shape. 
     The input and output of the signal obtained from the sensor part  301  in the example shown in  FIG. 22  is similar to the input and output described with reference to  FIG. 21 . The processing of the signal obtained from the sensor part  301  in the example shown in  FIG. 22  is similar to the processing described with reference to  FIG. 21 . 
     There is a reference example in which a SQUID (Superconducting Quantum Interference Device) magnetic sensor is used as a device to measure a faint magnetic field such as a magnetic field emitted from a living body, etc. Because superconductivity is used in the reference example, the device is large; and the power consumption is large. The load on the measurement object (the patient) is large. 
     According to the embodiment, the device can be small. The power consumption can be suppressed. The load on the measurement object (the patient) can be reduced. According to the embodiment, the SN ratio of the magnetic field detection can be improved. The sensitivity can be increased. 
     Embodiments may include the following configurations (e.g., technological proposals).
     Configuration 1
       A magnetic sensor, comprising:   a base body including a base body end portion;   a magnetic member, a direction from the base body toward the magnetic member being along a first direction; and   an element part,   the element part including a first magnetic element and a second magnetic element,   an orientation from the first magnetic element toward the second magnetic element being along a second direction crossing the first direction,   a portion of the first magnetic element and a portion of the second magnetic element being between the base body and the magnetic member in the first direction,   a position in a third direction of an other portion of the first magnetic element and a position in the third direction of an other portion of the second magnetic element being between a position in the third direction of the base body end portion and a position in the third direction of the magnetic member,   the third direction crossing a plane including the first and second directions.   
       Configuration 2
       The magnetic sensor according to Configuration 1, wherein   the element part further includes a first connection member,   the first connection member is electrically connected with one of one end portion or an other end portion of the first magnetic element, and   at least a portion of the first connection member is between the base body and the magnetic member in the first direction.   
       Configuration 3
       The magnetic sensor according to Configuration 2, wherein   the element part further includes a second connection member,   the second connection member is electrically connected with the other of the one end portion or the other end portion of the first magnetic element, and   a position in the third direction of the second connection member is between the position in the third direction of the base body end portion and a position in the third direction of at least one of the first magnetic element or the second magnetic element.   
       Configuration 4
       The magnetic sensor according to Configuration 3, wherein   at least a portion of the second magnetic element is between at least a portion of the second connection member in the third direction and at least a portion of the first connection member.   
       Configuration 5
       The magnetic sensor according to Configuration 3 or 4, wherein   the element part further includes a conductive member, and   the conductive member includes:
           a first corresponding portion corresponding to the first magnetic element; and   a second corresponding portion corresponding to the second magnetic element.   
           
       Configuration 6
       The magnetic sensor according to Configuration 5, wherein   the other end portion of the first magnetic element is electrically connected with one end portion of the second magnetic element,   an element current flows between the one end portion of the first magnetic element and an other end portion of the second magnetic element,   the first corresponding portion includes:
           a first corresponding one-portion corresponding to the one end portion of the first magnetic element; and   a first corresponding other-portion corresponding to the other end portion of the first magnetic element,   
           the second corresponding portion includes:
           a second corresponding one-portion corresponding to the one end portion of the second magnetic element; and   a second corresponding other-portion corresponding to the other end portion of the second magnetic element,   
           at a first time at which a first current that includes an alternating current component is supplied to the conductive member:
           the element current flows through the first magnetic element in an orientation from the one end portion of the first magnetic element toward the other end portion of the first magnetic element;   the element current flows through the second magnetic element in an orientation from the one end portion of the second magnetic element toward the other end portion of the second magnetic element;   the first current flows through the first corresponding portion in an orientation from the first corresponding other-portion toward the first corresponding one-portion; and   the first current flows through the second corresponding portion in an orientation from the second corresponding one-portion toward the second corresponding other-portion.   
           
       Configuration 7
       The magnetic sensor according to Configuration 3 or 4, wherein   the element part further includes a third magnetic element, a fourth magnetic element, and a third connection member,   an orientation from the first magnetic element toward the third magnetic element is along the second direction,   an orientation from the first magnetic element toward the fourth magnetic element is along the second direction,   the third connection member is electrically connected with one of the second magnetic element, the third magnetic element, or the fourth magnetic element, and   at least a portion of the third connection member is between the base body and the magnetic member in the first direction.   
       Configuration 8
       The magnetic sensor according to Configuration 7, wherein   the element part further includes a fourth connection member,   the fourth connection member is electrically connected with one of the second magnetic element, the third magnetic element, or the fourth magnetic element, and   a position in the third direction of the fourth connection member is between the position in the third direction of the base body end portion and a position in the third direction of the one of the second magnetic element, the third magnetic element, or the fourth magnetic element.   
       Configuration 9
       The magnetic sensor according to Configuration 7 or 8, wherein   the element part further includes a conductive member, and   the conductive member includes:
           a first corresponding portion corresponding to the first magnetic element;   a second corresponding portion corresponding to the second magnetic element;   a third corresponding portion corresponding to the third magnetic element; and   a fourth corresponding portion corresponding to the fourth magnetic element.   
           
       Configuration 10
       The magnetic sensor according to Configuration 9, wherein   the other end portion of the first magnetic element is electrically connected with one end portion of the second magnetic element,   the one end portion of the first magnetic element is electrically connected with one end portion of the third magnetic element,   an other end portion of the third magnetic element is electrically connected with one end portion of the fourth magnetic element,   an other end portion of the second magnetic element is electrically connected with an other end portion of the fourth magnetic element,   the first corresponding portion includes:
           a first corresponding one-portion corresponding to the one end portion of the first magnetic element; and   a first corresponding other-portion corresponding to the other end portion of the first magnetic element,   
           the second corresponding portion includes:
           a second corresponding one-portion corresponding to the one end portion of the second magnetic element; and   a second corresponding other-portion corresponding to the other end portion of the second magnetic element,   
           the third corresponding portion includes:
           a third corresponding one-portion corresponding to the one end portion of the third magnetic element; and   a third corresponding other-portion corresponding to the other end portion of the third magnetic element,   
           the fourth corresponding portion includes:
           a fourth corresponding one-portion corresponding to the one end portion of the fourth magnetic element; and   a fourth corresponding other-portion corresponding to the other end portion of the fourth magnetic element,   
           at a first time at which a first current that includes an alternating current component is supplied to the conductive member:
           an element current flows through the first magnetic element in an orientation from the one end portion of the first magnetic element toward the other end portion of the first magnetic element;   the element current flows through the second magnetic element in an orientation from the one end portion of the second magnetic element toward the other end portion of the second magnetic element;   the element current flows through the third magnetic element in an orientation from the one end portion of the third magnetic element toward the other end portion of the third magnetic element;   the element current flows through the fourth magnetic element in an orientation from the one end portion of the fourth magnetic element toward the other end portion of the fourth magnetic element;   the first current flows through the first corresponding portion in an orientation from the first corresponding other-portion toward the first corresponding one-portion;   the first current flows through the second corresponding portion in an orientation from the second corresponding one-portion toward the second corresponding other-portion;   the first current flows through the third corresponding portion in an orientation from the third corresponding one-portion toward the third corresponding other-portion; and   the first current flows through the fourth corresponding portion in an orientation from the fourth corresponding other-portion toward the fourth corresponding one-portion.   
           
       Configuration 11
       The magnetic sensor according to Configuration 9, wherein   the other end portion of the first magnetic element is electrically connected with one end portion of the second magnetic element,   the one end portion of the first magnetic element is electrically connected with one end portion of the third magnetic element, p 1  an other end portion of the third magnetic element is electrically connected with one end portion of the fourth magnetic element,   an other end portion of the second magnetic element is electrically connected with an other end portion of the fourth magnetic element,   the first corresponding portion includes:
           a first corresponding one-portion corresponding to the one end portion of the first magnetic element; and   a first corresponding other-portion corresponding to the other end portion of the first magnetic element,   
           the second corresponding portion includes:
           a second corresponding one-portion corresponding to the one end portion of the second magnetic element; and   a second corresponding other-portion corresponding to the other end portion of the second magnetic element,   
           the third corresponding portion includes:
           a third corresponding one-portion corresponding to the one end portion of the third magnetic element; and   a third corresponding other-portion corresponding to the other end portion of the third magnetic element,   
           the fourth corresponding portion includes:
           a fourth corresponding one-portion corresponding to the one end portion of the fourth magnetic element; and   a fourth corresponding other-portion corresponding to the other end portion of the fourth magnetic element,   
           the first corresponding one-portion is electrically connected with the third corresponding one-portion,   the first corresponding other-portion is electrically connected with the second corresponding one-portion,   the third corresponding other-portion is electrically connected with the fourth corresponding one-portion, and   the second corresponding other-portion is electrically connected with the fourth corresponding other-portion.   
       Configuration 12
       The magnetic sensor according to Configuration 11, further comprising:   a first current circuit,   the first current circuit being configured to supply the first current between a fifth connection point and a sixth connection point,   the first current including an alternating current,   the fifth connection point being between the first corresponding other-portion and the second corresponding one-portion,   the sixth connection point being between the third corresponding other-portion and the fourth corresponding one-portion.   
       Configuration 13
       The magnetic sensor according to Configuration 9, wherein   the other end portion of the first magnetic element is electrically connected with one end portion of the second magnetic element,   the one end portion of the first magnetic element is electrically connected with one end portion of the third magnetic element,   an other end portion of the third magnetic element is electrically connected with one end portion of the fourth magnetic element,   an other end portion of the second magnetic element is electrically connected with an other end portion of the fourth magnetic element,   the first corresponding portion includes:
           a first corresponding one-portion corresponding to the one end portion of the first magnetic element; and   a first corresponding other-portion corresponding to the other end portion of the first magnetic element,   
           the second corresponding portion includes:
           a second corresponding one-portion corresponding to the one end portion of the second magnetic element; and   a second corresponding other-portion corresponding to the other end portion of the second magnetic element,   
           the third corresponding portion includes:
           a third corresponding one-portion corresponding to the one end portion of the third magnetic element; and   a third corresponding other-portion corresponding to the other end portion of the third magnetic element,   
           the fourth corresponding portion includes:
           a fourth corresponding one-portion corresponding to the one end portion of the fourth magnetic element; and   a fourth corresponding other-portion corresponding to the other end portion of the fourth magnetic element,   
           the first corresponding one-portion is electrically connected with the second corresponding other-portion,   the first corresponding other-portion is electrically connected with the fourth corresponding one-portion,   the third corresponding one-portion is electrically connected with the fourth corresponding other-portion, and   the third corresponding other-portion is electrically connected with the second corresponding one-portion.   
       Configuration 14
       The magnetic sensor according to Configuration 12, further comprising:   a first current circuit,   the first current circuit being configured to supply the first current between a seventh connection point and an eighth connection point,   the first current including an alternating current,   the seventh connection point being between the first corresponding one-portion and the second corresponding other-portion,   the eighth connection point being between the third corresponding one-portion and the fourth corresponding other-portion.   
       Configuration 15
       The magnetic sensor according to Configuration 9, wherein   the other end portion of the first magnetic element is electrically connected with one end portion of the second magnetic element,   the one end portion of the first magnetic element is electrically connected with one end portion of the third magnetic element,   an other end portion of the third magnetic element is electrically connected with one end portion of the fourth magnetic element,   an other end portion of the second magnetic element is electrically connected with an other end portion of the fourth magnetic element,   the first corresponding portion includes:
           a first corresponding one-portion corresponding to the one end portion of the first magnetic element; and   a first corresponding other-portion corresponding to the other end portion of the first magnetic element,   
           the second corresponding portion includes:
           a second corresponding one-portion corresponding to the one end portion of the second magnetic element; and   a second corresponding other-portion corresponding to the other end portion of the second magnetic element,   
           the third corresponding portion includes:
           a third corresponding one-portion corresponding to the one end portion of the third magnetic element; and   a third corresponding other-portion corresponding to the other end portion of the third magnetic element,   
           the fourth corresponding portion includes:
           a fourth corresponding one-portion corresponding to the one end portion of the fourth magnetic element; and   a fourth corresponding other-portion corresponding to the other end portion of the fourth magnetic element,   
           the first corresponding other-portion is electrically connected with the fourth corresponding one-portion,   the fourth corresponding other-portion is electrically connected with the second corresponding other-portion, and   the second corresponding one-portion is electrically connected with the third corresponding other-portion.   
       Configuration 16
       The magnetic sensor according to Configuration 15, further comprising:   a first current circuit,   the first current circuit being configured to supply the first current between the first corresponding one-portion and the third corresponding one-portion,   the first current including an alternating current.   
       Configuration 17
       The magnetic sensor according to any one of Configurations 10 to 16, further comprising:   an element current circuit,   the element current circuit being configured to supply an element current between a first connection point and a second connection point,   the first connection point being between the one end portion of the first magnetic element and the one end portion of the third magnetic element,   the second connection point being between the other end portion of the second magnetic element and the other end portion of the fourth magnetic element.   
       Configuration 18
       The magnetic sensor according to Configuration 17, further comprising:   a detection circuit,   the detection circuit being configured to detect a change of a potential between a third connection point and a fourth connection point,   the third connection point being between the other end portion of the first magnetic element and the one end portion of the second magnetic element,   the fourth connection point being between the other end portion of the third magnetic element and the one end portion of the fourth magnetic element.   
       Configuration 19
       The magnetic sensor according to any one of Configurations 10 to 18, wherein   a portion of the conductive member overlaps the magnetic member in the first direction.   
       Configuration 20
       The magnetic sensor according to any one of Configurations 1 to 19, wherein   a length along the third direction of the portion of the first magnetic element is not more than 0.4 times a length along the third direction of the first magnetic element.   
       Configuration 21
       The magnetic sensor according to any one of Configurations 1 to 20, wherein   a ratio of a distance along the third direction between the base body end portion and the first magnetic element to the length along the third direction of the first magnetic element is not less than 1.5 times.   
       Configuration 22
       An inspection device, comprising:   the magnetic sensor according to any one of Configurations 1 to 21; and   a processor configured to process a signal output from the magnetic sensor.   
       

     According to embodiments, a magnetic sensor and an inspection device can be provided in which the sensitivity can be increased. 
     In the specification of the application, “perpendicular” and “parallel” refer to not only strictly perpendicular and strictly parallel but also include, for example, the fluctuation due to manufacturing processes, etc. It is sufficient to be substantially perpendicular and substantially parallel. 
     Hereinabove, exemplary embodiments of the invention are described with reference to specific examples. However, the embodiments of the invention are not limited to these specific examples. For example, one skilled in the art may similarly practice the invention by appropriately selecting specific configurations of components included in magnetic sensors such as magnetic elements, magnetic layers, nonmagnetic layers, magnetic members, conductive members, circuits, etc., from known art. Such practice is included in the scope of the invention to the extent that similar effects thereto are obtained. 
     Further, any two or more components of the specific examples may be combined within the extent of technical feasibility and are included in the scope of the invention to the extent that the purport of the invention is included. 
     Moreover, all magnetic sensors, and inspection devices practicable by an appropriate design modification by one skilled in the art based on the magnetic sensors, and the inspection devices described above as embodiments of the invention also are within the scope of the invention to the extent that the purport of the invention is included. 
     Various other variations and modifications can be conceived by those skilled in the art within the spirit of the invention, and it is understood that such variations and modifications are also encompassed within the scope of the invention. 
     While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the invention.