JPWO2013129276A1 - Magnetic sensor element - Google Patents

Abstract

An object of the present invention is to provide a magnetic sensor element capable of detecting an external magnetic field to be detected over a wide range with high sensitivity and low power consumption. The present invention includes a magnetoresistive effect element for detecting an external magnetic field, and a compensation current line for applying a compensation magnetic field to the magnetoresistive effect element when a compensation current flows. The magnetoresistive effect element includes first and second current lines arranged in parallel so as to sandwich the magnetoresistive element between the upper and lower sides through an insulating film, and a connection conductor connecting them. The magnetic sensor element is characterized by flowing two current lines in an antiparallel direction. [Selection] Figure 4

Description

  The present invention relates to a small magnetic sensor element capable of detecting an external magnetic field.

  In general, as a method of measuring a control current for controlling a control device or the like, there is a method of measuring indirectly by detecting a gradient of a current magnetic field generated by the control current. Specifically, for example, Patent Document 1 uses four magnetoresistive elements such as giant magnetoresistive elements (hereinafter referred to as GMR elements) that exhibit giant magnetoresistive effects (Wheatstone bridge). And is placed in the above-described current magnetic field to detect the gradient thereof. In this way, by forming the Wheatstone bridge, it is possible to suppress the influence of the disturbing magnetic field from the outside and the environmental temperature relatively low. In particular, when the characteristics of the four magnetoresistive elements are uniform, more stable detection characteristics can be obtained.

  Further, Patent Document 2 discloses an example in which a change in output voltage caused by an environmental temperature or an external disturbing magnetic field is further reduced by providing a measurement bridge and a compensation current line.

  Furthermore, as disclosed in Patent Document 3, by using two magnetoresistive elements, it is easier to balance than the four cases, and it is easy to reduce the resistance value offset in a zero magnetic field. Further, Patent Document 3 discloses a technique for measuring a detection target current with higher accuracy by using a compensation current corresponding to a difference in voltage drop in a plurality of magnetoresistive elements.

  In Patent Document 4, a current magnetic field is highly sensitive and accurate using a plurality of magnetoresistive effect elements, a bridge circuit, and a compensation current line having a band-shaped portion extending together with each magnetoresistive effect element. A current sensor for measuring is disclosed.

  FIG. 14 shows a diagram similar to FIG. 3 of Patent Document 4, but with the reference numerals changed. Since Patent Document 4 is the main prior art of the present invention, hereinafter, FIG. 14 will be used as a comparative example. FIG. 14 is a diagram showing a configuration of a conventional current sensor 100. As the four magnetoresistive effect elements, there are first to fourth magnetoresistive effect elements 21 to 24, and a compensation current line 300 is formed in a strip shape along each of the four magnetoresistive effect elements. The part of the line 300 corresponding to the first to fourth magnetoresistive elements 21 to 24 is the first to fourth strip-shaped compensation current lines 310, 320, 330, and 340. In addition, there is a portion 370 of the band-shaped compensation current line 300 that does not extend along the magnetoresistive element.

  The detection principle of a current sensor typified by Patent Document 4 will be briefly described. Compensates in the anti-parallel direction to the induced magnetic field so that the induced magnetic field generated from the detected current flowing in the detected conductor is canceled from the current sensor side and the magnitude of the magnetic field becomes zero. Generate a magnetic field. A compensation magnetic field arises from the compensation current which flows into the compensation current line which a current sensor has. The equilibrium point where the strength of the magnetic field becomes zero detects a point where the magnetic field detection output of the magnetoresistive effect element of the current sensor becomes zero. Since the magnitude of the compensation current when reaching this equilibrium point is proportional to the magnitude of the induced magnetic field and current to be detected, the principle is that if the value of the compensation current is known, the current to be detected generated in the conductor can be detected. It is.

Japanese Patent Laid-Open No. 06-294854 Japanese National Patent Publication No. 10-506193 Japanese Patent Laid-Open No. 2006-105693 JP 2011-196798 A

  As shown in the above-mentioned document, regarding the magnetic sensor element, in addition to downsizing the overall configuration, high performance is required, but in order to efficiently detect the target magnetic field, low power consumption is required. It has been demanded. The present invention has been made in view of such problems, and an object thereof is to provide a magnetic sensor element capable of detecting a detection target external magnetic field over a wide range with high sensitivity and low power consumption.

  The present invention relates to a magnetoresistive effect in a direction different from an external magnetic field by flowing a compensation current, a magnetoresistive effect element whose resistance changes in accordance with an external magnetic field formed on the substrate, and a compensation current. A compensation current line applied to the element, and the compensation current line sandwiches the magnetoresistive effect element from the second direction opposite to the first direction and the first direction via the insulating film. The first and second current lines and the magnetoresistive effect element including first and second current lines arranged in parallel and a first connection conductor connecting the first and second current lines in series. In the normal direction of the substrate has a region that overlaps in the entire region in the longitudinal direction of the magnetoresistive effect element, and the compensation current is obtained by applying the first and second current lines to the longitudinal direction of the magnetoresistive effect element. Magnetic sensor elements characterized by flowing in antiparallel directions along each other It is.

  With this configuration, not only the magnetic field generated from the compensation current line sandwiching the magnetoresistive effect element but also the magnetic field generated from the first connection conductor connecting the compensation current line sandwiching the magnetoresistive effect element is magnetoresistive. Since the magnetic field generated per unit compensation current increases because it is applied to the effect element section, each band-shaped compensation current line correspondingly extending together with each magnetoresistive effect element of FIG. It is possible to increase the sensitivity and reduce the power consumption by reducing the resistance by reducing the length corresponding to the band-shaped compensation current line other than that, and by reducing the compensation current.

  Furthermore, the magnetic sensor element of the present invention is characterized in that an insulating film having a thickness of 10 times or more of the thickness of the magnetoresistive effect element is provided between the magnetoresistive effect element and the compensation current line.

  Furthermore, the magnetic sensor element of the present invention is characterized in that the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film exceeds 300 nm.

  Furthermore, the magnetic sensor element of the present invention is characterized in that the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film is 500 nm or more.

  By providing such an insulating film, it is thick enough not to be destroyed by a voltage difference generated between the compensation current line and the magnetoresistive effect element, and a magnetic field from the compensation current line can be sufficiently applied to the magnetoresistive effect element. It is thin to the extent.

  Furthermore, in the magnetic sensor element of the present invention, the magnetoresistive effect element includes a pinned layer having a magnetization direction fixed in a certain direction, an intermediate layer, and a free layer whose magnetization direction changes according to an external magnetic field, The magnetization direction of the pinned layer is a direction orthogonal to the extending direction of the compensation current line.

  Furthermore, the magnetic sensor element of the present invention is characterized by including a permanent magnet that applies a bias magnetic field in a direction orthogonal to the magnetization direction of the pinned layer.

  Furthermore, the magnetic sensor element of the present invention includes a plurality of second connection conductors on the opposite side of the first connection conductor across the first and second current lines, and a plurality of magnetoresistance effect elements. A plurality of magnetoresistive effect elements arranged in parallel in a third direction different from the extending direction of the compensation current lines, and flowing in each of the first and second current lines provided in each of the plurality of magnetoresistive effect elements. The first and second current lines respectively provided in the plurality of magnetoresistive elements are connected to the plurality of first and second connections so that the compensation current flows in an antiparallel direction along the longitudinal direction of the plurality of magnetoresistive elements. It is characterized by being connected by a conductor.

  Furthermore, the magnetic sensor element of the present invention includes first to fourth magnetoresistance effect elements as magnetoresistance effect elements, and one ends of the first and second magnetoresistance effect elements are connected at the first connection point. The one ends of the third and fourth magnetoresistive elements are connected at the second connection point, and the other end of the first magnetoresistive element and the other end of the fourth magnetoresistive element are the third. The other end of the second magnetoresistive effect element and the other end of the third magnetoresistive effect element are connected at the fourth connection point to form a bridge circuit. The current is generated by a potential difference between the third connection point and the fourth connection point when a voltage is applied between the first connection point and the second connection point. The resistance values of the magnetoresistive effect elements 3 are mutually dependent on the external magnetic field. And the resistance values of the second and fourth magnetoresistive elements change in opposite directions to the first and third magnetoresistive elements in accordance with the external magnetic field. Yes.

  According to the magnetic sensor element of the present invention, the detection target external magnetic field can be detected with high sensitivity and low power consumption.

It is a perspective view showing the whole magnetic sensor composition of this embodiment. It is a perspective view showing the whole structure of the current sensor of this embodiment. It is a perspective view of the strip | belt-shaped compensation current line pair of this embodiment. It is a perspective view of the magnetic sensor element of this embodiment. It is a disassembled perspective view of the magnetic sensor element of this embodiment. It is a schematic diagram which shows the mode of the magnetic field of the current sensor of this embodiment. It is a schematic diagram of another embodiment whose strip | belt-shaped part of a magnetoresistive effect element is meander shape. It is a schematic diagram of another embodiment whose strip | belt-shaped part of a magnetoresistive effect element is meander shape. It is a disassembled perspective view showing the film | membrane structure of the magnetoresistive effect element of this embodiment. It is a disassembled perspective view showing the film | membrane structure of the magnetoresistive effect element of this embodiment. It is a bridge circuit diagram of this embodiment. It is a figure which shows distribution of the compensation magnetic field on the magnetoresistive effect element of this embodiment. It is a characteristic view of the compensation current of this embodiment, and the output of a magnetoresistive effect element. It is a figure which shows the relationship between the insulating film thickness of this embodiment, and a breakdown voltage. It is a bridge circuit figure of the modification of this embodiment. It is a perspective view of the current sensor element of a comparative example. It is a schematic diagram which shows the mode of the magnetic field of magnetic sensors other than the current sensor of this embodiment.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In addition, this invention is not limited to the following embodiment. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

(Description of basic configuration)
FIG. 1 is a perspective view showing the overall configuration of the magnetic sensor 10 of the present embodiment. A magnetic sensor element 1 including a magnetoresistive effect element 20 is installed on a substrate 5, and a permanent magnet 9 for applying a bias magnetic field described later is further arranged. The magnetic sensing direction of the magnetic sensor element 1 is parallel to the magnetization fixed direction of the magnetization fixed layer of the magnetoresistive effect element 20. The magnetic sensor element 1 detects the value of the magnetically sensitive direction component described above from an external magnetic field in an arbitrary direction.

  FIG. 2 is a perspective view showing the overall configuration of the current sensor 1000 using the magnetic sensor 10 of the present embodiment. The current sensor 1000 includes the magnetic sensor 10, the conductor 2, and the shield structure 6. Specifically, in addition to the magnetic sensor 10 of FIG. 1, the current sensor 1000 includes a conductor 2 through which the detection target current Im flows, an induction magnetic field Hm generated from the current, and a shield structure 6 that shields a disturbance magnetic field other than the induction magnetic field. .

  FIG. 3 is a perspective view of the band-shaped compensation current line pair 35 of the magnetic sensor element 1 provided in the current sensor 1000 of the present embodiment, and FIG. 4 is a perspective view of the magnetic sensor element 1 of the present embodiment. is there. FIG. 5 is an exploded perspective view of the magnetic sensor element 1 of the present embodiment. The configuration of this embodiment will be described with reference to FIGS. The magnetic sensor element 1 of this embodiment is the magnetic sensor element 1 provided in the current sensor 1000. Further, the magnetic sensor element 1 of the present embodiment includes a magnetoresistive effect element 20 and a compensation current line 30. The compensation current line 30 is composed of at least one set or a plurality of sets of band-shaped compensation current line pairs 35.

  One magnetoresistive effect element 20 of the magnetic sensor element 1 of this embodiment is arranged for one set of the band-shaped compensation current line pair 35. At least one set or a plurality of sets of the band-shaped compensation current line pairs 35 are provided for one magnetic sensor element 1.

  The band-shaped compensation current pair 35 which is the compensation current line 30 generates a compensation current Id and generates an antiparallel compensation magnetic field Hd with respect to the induced magnetic field Hm generated from the conductor 2 through which the linear detection target current Im flows. It is generated on the resistance effect element 20. Here, antiparallel means that the directions of a pair of flowing currents and a pair of magnetic fields are opposite to each other when viewed in a uniaxial direction.

  As shown in FIG. 3, the pair of band-shaped compensation current line pairs 35 includes a first current line 301 and a second current line 302. The first current line 301 and the second current line 302 sandwich the magnetoresistive effect element 20 from the first direction and the second direction opposite to the first direction, that is, in the Z-axis direction. In addition, the first current line 301 and the second current line 302 are connected in series by the first connecting conductor 7 so as to sandwich the upper and lower sides, and further, the first current line A range obtained by projecting 301, the second current line 302, and the magnetoresistive effect element in the normal direction of the substrate is a so-called solenoid shape having an overlapping area in the entire longitudinal direction of the magnetoresistive effect element. By adopting such a shape, the compensation current Id flows through the first current line 301 and the second current line 302 in antiparallel directions along the longitudinal direction of the magnetoresistive effect element.

  FIG. 6 shows a schematic cross section of the current sensor 1000 parallel to the XZ plane of FIG. 2, and a first band-shaped compensation current line pair 35 is formed vertically across the magnetoresistive effect element 20 in the Z-axis direction. A current line 301 and a second current line 302 are arranged. FIG. 6 is a schematic diagram showing the relationship between the compensation current Id and the compensation magnetic field Hd, and the direction in which the detection target current Im generated from the conductor 2 and the detection target induction magnetic field Hm flow or occur.

  According to FIG. 6, the compensation magnetic field Hd on the current sensor side with respect to the direction of the induction magnetic field Hm to be detected is the compensation magnetic field Hd generated from the first current line 301 and the compensation magnetic field generated from the second current line 302. Hd is strengthened and combined to become a combined compensation magnetic field Hd2, which is antiparallel to the induced magnetic field Hm. As a result, the induced magnetic field Hm and the combined compensated magnetic field Hd2 cancel each other.

  FIG. 15 is the same as FIG. 6 and is used to explain the direction of the external magnetic field H and the compensation magnetic field Hd that reach the magnetoresistive effect element and the combined compensation magnetic field Hd2 of the compensation magnetic field of the magnetic sensor elements other than the current sensor. It is a schematic diagram. Among the components of the external magnetic field H, the X component in the figure, which is the magnetosensitive direction of the magnetoresistive element 20, is detected.

  The magnetic sensor element 1 provided in the current sensor 1000 of the present embodiment is composed of the magnetoresistive effect element 20 and the compensation current line 30. The band-shaped compensation current line pair 35 constituting the compensation current line 30 is At least one set or a plurality of sets are provided. For example, the compensation current line 30 of the magnetic sensor element 1 is composed of four pairs of band-shaped compensation current line pairs 35, that is, four magnetoresistive effect elements 20. Is shown in FIG.

  By forming the solenoid shape as shown in FIG. 4, the respective band-shaped compensation current lines 310 to 340 correspondingly extending together with the magnetoresistive elements 21 to 24 as shown in FIG. 14 of the comparative example as the prior art. Since the band-shaped compensation current line 370 other than is unnecessary, the length can be shortened. That is, three strip-shaped compensation current lines 370 that are not close to the magnetoresistive elements 21 to 24 are not necessary. Thus, the resistance of the compensation current line can be reduced by reducing the length of the compensation current line.

  With such a configuration, not only the magnetic field generated from the band-shaped compensation current line pair 35 that is the compensation current line 30 sandwiching the magnetoresistive effect element 20, but also the band-shaped compensation current line pair 35 sandwiching the magnetoresistive effect element 20 is interposed. In series, the magnetic field generated from the first connection conductor 7 that connects the first and second current lines 301 and 302 up and down is also applied to the magnetoresistive effect element unit 20, so that the unit The generated magnetic field per compensation current increases, and as a result, the compensation current Id value can be suppressed. Even if the compensation current Id value is suppressed, the generated magnetic field per unit compensation current is increased, and as a result, the sensitivity of the magnetic sensor element 1 is increased. Incidentally, the sensitivity is defined as the amount of change in resistance of the magnetoresistive element per unit compensation current when the compensation current is applied. Therefore, if the generated magnetic field per unit compensation current increases, the resistance change per unit compensation current increases, so the sensitivity increases.

  The power consumption can be reduced by increasing the sensitivity by the effect of reducing the resistance of the compensation current line and reducing the compensation current Id with respect to the detection target external magnetic field.

  The magnetoresistive effect element 20 used for the magnetic sensor element 1 provided in the current sensor 1000 of the present embodiment is a band-shaped element as shown in FIGS. 3 to 5, and one or two in the plane. Alternatively, it is preferable to provide four. Further, at least one set or a plurality of sets of band-shaped compensation current line pairs 35 are provided for one magnetoresistive effect element 20. When a plurality of magnetoresistive effect elements 20 are provided, it is preferable that the magnetoresistive effect elements 20 are arranged in parallel in a third direction different from the extending direction of the compensation current line pair. Here, the third direction is a direction orthogonal to the normal line of the substrate, and refers to a direction other than the same direction as the extending direction of the compensation current line pair. Here, the compensation current flowing through the first and second current lines 301 and 302 included in each of the plurality of magnetoresistive effect elements 20 flows in an antiparallel direction along the longitudinal direction of the magnetoresistive effect element 20. The first and second current lines 301 and 302 are a plurality of second connection conductors 15 and first connection conductors 7 that are on the opposite side of the first connection conductor across the first and second current lines. And connected by. As described above, when a plurality of magnetoresistive elements 20 are provided, the compensation currents flowing in the first and second current lines 301 and 302 respectively provided for the plurality of magnetoresistive elements 20 are antiparallel. Since the first connection conductor 7 and the second connection conductor 15 exist so that a current flows through the compensation current Id, the compensation current Id value can be suppressed. Even if the compensation current Id value is suppressed, the generated magnetic field per unit compensation current is increased, and as a result, the sensitivity of the magnetic sensor element 1 is increased. Further, the third direction is preferably a direction orthogonal to the extending direction of the compensation current line pair. In this case, since the plurality of magnetoresistive elements 20 are densely arranged, the first and second current lines Since it is possible to reduce the overall lengths of the first and second connection conductors 301 and 302 and the second connection conductor 15, it is possible to reduce the electrical resistance. Note that the first connection conductor 7 and the second connection conductor 15 preferably connect the end portions of the first and second current lines 301 and 302 to each other. Here, when connecting the end portions, a straight line connecting the end portions and a region where the first connection conductor 7 and the second connection conductor 15 are projected onto the substrate connect the end portions. It is preferable that they overlap in the whole area of the straight line. With such a configuration, it becomes possible to reduce the resistance value of the first connection conductor 7 and the second connection conductor 15, and the existence region of the first connection conductor 7 and the second connection conductor 15. Can be reduced. Therefore, the power consumption and size reduction of the magnetic sensor element 1 can be achieved.

  The compensation current Id generated with respect to the induction magnetic field Hm generated from the conductor 2 through which the linear detection target current Im flows flows through the first and second current lines 301 and 302 in the antiparallel direction. Even when a plurality of band-shaped compensation current line pairs 35 are provided for one magnetoresistive effect element 20, the direction of current flowing through each pair must be the same direction and must flow antiparallel. That is, when there are four pairs of band-shaped compensation current line pairs 35, the compensation current Id flowing through each first current line 301 flows in the same direction and the compensation flowing through each second current line 302 in all four sets. The current Id flows in the same direction, and all four sets flow in antiparallel directions on the first and second current lines 301 and 302, respectively.

  In FIG. 3, regarding the magnetoresistive effect element 20 sandwiched between the band-shaped compensation current line pair 35, the magnetoresistive effect element 20 and the first and second current lines 301 and 302 are separated from each other by an insulating film. Although not shown, the insulating film is thick enough not to be destroyed by a voltage difference generated between the first current line 301 or the second current line 302 and the magnetoresistive effect element 20, and has a compensation magnetic field Hd. Can be applied to the magnetoresistive effect element 20 with sufficient strength, and sufficient withstand voltage can be obtained. I can do it.

  A specific configuration of the magnetic sensor element 1 constituting the current sensor 1000 of the present embodiment will be described with reference to FIGS. As shown in FIG. 2, the current sensor 1000 includes a linear conductor 2 through which a detection target current Im flows, a substrate 5 disposed in the vicinity of the conductor 2, and a magnetic sensor disposed on the substrate 5. Device 1 is provided. Further, a permanent magnet 9 for applying a bias magnetic field to the free layer 63 of the magnetoresistive effect element 20 is disposed on the magnetic sensor element 1 along the extending direction of the conductor 2, that is, the Y-axis direction. Yes. The magnetic sensor 10 includes a substrate 5, a permanent magnet 9, and a magnetic sensor element 1 as shown in FIG. 1, and is also included in this embodiment.

  Further, a cylindrical shield structure 6 made of a magnetic material such as ferrite is provided so as to surround the conductor 2 and the current sensor 1000 in a lump. The conductor 2 is made of a metal material having high conductivity such as copper (Cu), for example, and generates an induction magnetic field Hm around the detection target current Im. The shield structure 6 functions to prevent an unnecessary external magnetic field from reaching the magnetic sensor 10 including the magnetic sensor element 1.

  For example, as shown in FIG. 4, the magnetic sensor element 1 has four first to fourth magnetoresistive effects as shown in FIG. 9 on the substrate 5 in the case where four pairs of band-shaped compensation current line pairs 35 are provided. There are a hierarchy in which the detection circuit 41 including the elements 21 to 24 is provided, and four pairs of band-shaped compensation current line pairs 35 so as to sandwich the detection circuit 41, a hierarchy including the first current line 301, and a second current line 302. 9, a hierarchy including the first current line 301, a hierarchy including the first to fourth magnetoresistance effect elements 21 to 24 and the detection circuit in FIG. 9, and the second current line 302. Are formed in the order of the layers including

  In FIG. 4, the four, that is, the first to fourth magnetoresistive elements of the present embodiment extend in the same direction, that is, in the Y-axis direction.

  In FIG. 5, the four magnetoresistive elements 21 to 24, that is, the first to fourth magnetoresistive elements 21 to 24 have the dimension of the width W2 in the extending direction and the thickness direction, that is, the direction orthogonal to the Z-axis direction. doing. The width W2 may be equal to each other or different from each other.

  The magnetoresistive effect element 20 has a one-to-one correspondence with the band-shaped compensation current line pair 35 in the compensation current line 30. That is, as shown in FIG. 3, the magnetoresistive effect element 20 is in a position overlapping the band-shaped compensation current pair 35 in the stacking direction of the magnetoresistive effect element, that is, the Z-axis direction. Further, as seen in FIG. 5, the first to fourth magnetoresistive elements 21 to 24 are in a positional relationship where they overlap with each other in the thickness direction with the first to fourth strip-shaped compensation current line pairs 31 to 34, respectively. This is preferable because it is influenced by the compensation magnetic field Hd from the first to fourth strip-shaped compensation current line pairs 31 to 34 together with the induction magnetic field Hm.

In the example where four pairs of band-shaped compensation current line 35 are provided, as shown in FIG. 5, the first to fourth magnetoresistive effect elements 21 to 24, the detection circuit 41 at the same level as the magnetoresistive effect element, and the first The first to fourth strip-shaped compensation current line pairs 31 to 34 are each embedded with an insulating film made of alumina (Al ₂ O ₃ ) and insulated from each other. Further, although treated as the band-shaped compensation current line pair 35, the first current line 301 and the second current line 302 constituting the first to fourth band-shaped compensation current line pairs 31 to 34 are respectively The first connecting conductor 7 and the second connecting conductor 15 extending in the Z direction are connected. In addition to Al ₂ O _3, the insulating film may be silicon oxide (SiO ₂ ) or silicon nitride (Si ₃ N ₄ ).

The element substrate 5 is made of, for example, an insulating film such as Al ₂ O ₃ or SiO ₂ on a silicon (Si) compound such as glass or SiO ₂ , an insulating material such as Al ₂ O ₃ , or a conductive material such as Si. It is comprised with the material which laminated | stacked.

  The compensation current line 30 including the band-shaped compensation current line pair shown in the drawings including FIG. 4 is made of a metal material having high conductivity such as Cu, and is routed so as to sandwich the laminated surface of the magnetoresistive effect element 20. This is a thin film conductor. The compensation current line 30 is configured such that the compensation current Id from the detection circuit 41 in FIG. 9 flows from one end, for example. As a part of the compensation current line 30, the extending direction of the magnetoresistive effect element 20, that is, linearly extends in the Y-axis direction, and the thickness direction, that is, the width direction orthogonal to the Z-axis direction, that is, Four pairs of band-shaped compensation current line pairs 35 arranged in the X-axis direction are included.

  As shown in FIG. 4, the band-shaped compensation current line pair 35 includes a first current line 301 and a second current line 302, and the first current line 301 and the second current line 302 have a magnetoresistance. The effect element 20 is disposed in parallel so as to sandwich the effect element 20 from the first direction and the second direction, that is, in the Z-axis direction so as to sandwich the top and bottom, and the first current line 301 and the second direction The current line 302 is connected in series by the first connection conductor 7 and the second connection conductor 15. Each of the first current line 301 and the second current line 302 has a width W1 in the width direction. The widths W1 may be equal to each other or different from each other.

  In the magnetic sensor element 1 of the present embodiment, the thickness of the compensation current line 30 may be different for each line. Further, the compensation current line 30 may be disposed in a portion that does not overlap the magnetoresistive effect element 20. Thereby, the magnetic field applied to the magnetoresistive effect element 20 by the compensation current line 30 can be made uniform. Variation in the resistance change amount of the magnetoresistive effect element 20 can be suppressed.

  As another form, the belt-like portions may be connected in series in a meander shape like a zigzag. When the magnetoresistive effect element is configured in a meander shape, the influence of the magnetic field generated when the magnetoresistive effect element is energized, that is, the influence of the self-bias magnetic field can be canceled by setting the number of the band-like portions to an even number. FIG. 7a is an example in which one resistor is made of two magnetoresistive elements. FIG. 7b shows an example in which one resistor is made of four magnetoresistive elements. In the figure, 3 is an electrode and 4 is an intermediate electrode.

  The first connection conductor 7 and the second connection conductor 15 connect the first current line 301 and the second current line 302 of the band-shaped compensation current pair 35, for example, in the Z-axis direction as shown in FIG. To do. The first connecting conductor 7 and the second connecting conductor 15 as shown in FIG. 4 are formed by forming the first connecting conductor 7 and the second connecting conductor 15 by Cu plating patterned with photo, and then forming an insulating film. By laminating and removing the insulating film laminated on the first connecting conductor 7 and the second connecting conductor 15 by CMP or the like, or by making a hole in the insulating film by RIE and filling the hole portion with Cu The first connection conductor 7 and the second connection conductor 15 can be produced by a known technique such as formation.

  The band-shaped compensation current line pair 35 constituting the compensation current line 30 of the present embodiment extends in the same direction as the extending direction of the magnetoresistive effect element 20 and overlaps the magnetoresistive effect element 20 in the thickness direction. Preferably it is. The insulating film (not shown) that separates the band-shaped compensation current line pair 35 of the compensation current line 30 and the magnetoresistive effect element 20 is not destroyed by a voltage difference generated between the band-shaped compensation current line pair 35 and the magnetoresistive effect element. It is so thick that the magnetic field from the band-shaped compensation current line pair 35 can be sufficiently applied to the magnetoresistive element.

  At least a part of the band-shaped compensation current line pair 35 overlaps the magnetoresistive effect element 20 in the thickness direction, and the film thickness of the insulating film separating the band-shaped compensation current line pair 35 and the magnetoresistive effect element 20 is optimized. Therefore, while maintaining the withstand voltage between the magnetoresistive effect element 20 and the compensation current line pair 35, the maximum intensity and the average intensity of the effective magnetic field that actually reaches the magnetoresistive effect element 20 in the compensation magnetic field Hd are improved.

  In the present embodiment, the thickness of the insulating film separating the band-shaped compensation current line pair 35 and the corresponding magnetoresistive effect element 20 is set to 10 times or more the thickness of the magnetoresistive effect element 20. FIG. 12 is a diagram showing the relationship between the film thickness of the insulating film and the breakdown voltage of the magnetoresistive effect element 20. When the thickness of the magnetoresistive effect element 20 is about 30 nm and the thickness of the insulating film is greater than about 300 nm, the breakdown voltage of the magnetoresistive effect element 20 tends to increase from 0. Is not destroyed by the voltage difference generated between the compensation current line 30 and the magnetoresistive element 20. Even in the case where the thickness of the magnetoresistive effect film is different from 30 nm, it is preferable that the thickness of the insulating film exceeds 300 nm because the minimum breakdown voltage is not 0 as in the result of FIG. When the thickness of the insulating film is 500 nm or more, the minimum breakdown voltage is almost constant, which is more preferable. As the material for the insulating film, for example, metal oxides such as alumina (Al 2 O 3), silicon oxide (SiO 2) and silicon nitride (Si 3 N 4), metal nitrides, organic substances such as polyimide, or mixtures thereof are preferable.

(Description of magnetoresistive effect element)
The configuration of the magnetoresistive element 20 will be described in detail with reference to FIGS. 8a and 8b. 8a and 8b are exploded perspective views showing the structure of the magnetoresistive element 20 in an exploded manner. Since the first to fourth magnetoresistive elements 21 to 24 shown in FIGS. 4 and 5 have the same configuration except for the direction of the magnetization J61, here, the magnetoresistance of FIG. The effect element 20 will be described as an example.

  The magnetoresistive effect element 20 has a spin valve structure and is a giant magneto-resistive effect element.

  As shown in FIG. 8a, the magnetoresistive element 20 includes a pinned layer 61 having a magnetization direction fixed in a certain direction, an intermediate layer 62, and a free layer 63 whose magnetization direction changes according to an external magnetic field in order. The laminated body 60 is included. In that case, the magnetization direction of the pinned layer 61 may be a direction orthogonal to the extending direction of the conductor 2 and the band-shaped compensation current line pair 35.

  More specifically, as shown in FIG. 8a, for example, a pinned layer 61 having a magnetization J61 pinned in the + X direction, a nonmagnetic intermediate layer 62 that does not exhibit a specific magnetization, an induced magnetic field Hm, and a compensation magnetic field A free layer 63 having a magnetization J63 that varies depending on the magnitude and direction of the applied magnetic field, such as Hd, is sequentially stacked. The easy axis AE63 of the free layer 63 is preferably parallel to the Y axis.

  The magnetization directions of the first to fourth magnetoresistive elements 21 to 24 of this embodiment will be described. As shown in FIG. 9, the magnetization J61 of the third magnetoresistance effect element 23 is fixed in the same direction (+ X direction) as the magnetization J61 of the first magnetoresistance effect element 21. On the other hand, the magnetization J61 of the second and fourth magnetoresistive elements 22 and 24 is fixed in the opposite direction (−X direction) to the magnetization J61 of the first and third magnetoresistive elements 21 and 23. ing.

  FIG. 8a shows a no-load state in which the induction magnetic field Hm and the compensation magnetic field Hd are not applied, that is, a state in which the external magnetic field is zero. In this case, the magnetization direction J63 of the free layer 63 is parallel to its own easy axis AE63 and is almost orthogonal to the magnetization J61 of the pinned layer 61.

  The free layer 63 is made of a soft magnetic material such as NiFe. The intermediate layer 62 is made of Cu, and has an upper surface in contact with the fixed layer 61 and a lower surface in contact with the free layer 63. The intermediate layer 62 can be made of nonmagnetic metal having high conductivity such as gold (Au) in addition to Cu. The intermediate layer 62 also functions as a pass line through which most of the read currents I1 and I2 shown in FIG. 6 supplied during operation of the current sensor flow. Note that the lower surface of the free layer 63, that is, the surface opposite to the surface in contact with the intermediate layer 62 may be protected by a protective film (not shown).

  An exchange bias magnetic field Hin in the magnetization direction J61 is generated between the pinned layer 61 and the free layer 63, and interacts with each other via the intermediate layer 62. The intensity of the exchange bias magnetic field Hin changes as the spin direction of the free layer 63 rotates according to the mutual distance between the fixed layer 61 and the free layer 63, that is, the thickness of the intermediate layer 62. Therefore, the exchange bias magnetic field Hin can be apparently zero.

  Here, as shown in FIG. 2, a permanent magnet 9, which is a bias application unit that applies a bias magnetic field in a direction orthogonal to the magnetization direction of the pinned layer 61, may be provided on the stacked body 60. The permanent magnet 9 functions to reduce the hysteresis by applying a bias magnetic field to the free layer 63 of the magnetoresistive effect element 20.

8A shows a configuration example in which the free layer 63, the intermediate layer 62, and the fixed layer 61 are stacked in this order from the bottom. However, the configuration is not limited to this, and may be configured in the opposite order. Good. Note that a TMR (Tonneling Magneto Resistive) element in which the intermediate layer 62 is an insulator such as Al ₂ O ₃ or magnesium oxide (MgO) may be used.

  FIG. 8 b shows a detailed configuration of the fixing layer 61. The pinned layer 61 has a configuration in which, for example, a magnetization fixed film 64, an antiferromagnetic film 65, and a protective film 66 are sequentially stacked from the intermediate layer 62 side. The magnetization fixed film 64 is made of a ferromagnetic material such as cobalt (Co) or cobalt iron alloy (CoFe), and the magnetization direction indicated by the magnetization fixed film 64 is the direction of the magnetization J61 as the entire fixed layer 61. .

  On the other hand, the antiferromagnetic film 65 is made of an antiferromagnetic material such as platinum manganese alloy (PtMn) or iridium manganese alloy (IrMn). The antiferromagnetic film 65 is in a state in which the spin magnetic moment in the + X direction and the spin magnetic moment in the opposite direction (−X direction) are completely cancelled, and the magnetization direction of the magnetization fixed film 64, that is, The fixed layer 61 acts to fix the direction of the magnetization J61. The protective film 66 is made of a relatively chemically stable nonmagnetic material such as tantalum (Ta) or hafnium (Hf), and protects the magnetization fixed film 64, the antiferromagnetic film 65, and the like.

  In the magnetoresistive effect element 20 having the above structure, the magnetization J63 of the free layer 63 is rotated by the application of the combined magnetic field of the induction magnetic field Hm and the compensation magnetic field Hd, thereby changing the relative angle between the magnetization J63 and the magnetization J61. To do. The relative angle is determined by the magnitude and direction of the induction magnetic field Hm and the compensation magnetic field Hd. Here, the direction of the induction magnetic field Hm is the + X direction, whereas the direction of the compensation magnetic field Hd is the −X direction. Usually, the induction magnetic field Hm has a greater strength than the compensation magnetic field Hd. The direction of is the + X direction. Therefore, the magnetization J63 of the free layer 63 in the magnetoresistive effect element 20 is inclined in the + X direction from the no-load state shown in FIG. 8a, and each resistance value of the magnetoresistive effect element 20 increases or decreases.

  More specifically, since the magnetization J61 is in the + X direction in the first and third magnetoresistance effect elements 21 and 23 of the present embodiment, the magnetization J63 is applied when a combined magnetic field of the induction magnetic field Hm and the compensation magnetic field Hd is applied. Approaches the state parallel to the magnetization J61, and its resistance value decreases. On the other hand, since the magnetization J61 is in the −X direction in the second and fourth magnetoresistance effect elements 22 and 24, the magnetization J63 is antiparallel to the magnetization J61 when a combined magnetic field of the induction magnetic field Hm and the compensation magnetic field Hd is applied. As the state approaches, the resistance value increases.

(Description of detection circuit)
The circuit configuration of the current sensor according to this embodiment will be described with reference to FIG. FIG. 9 is a detection circuit diagram of this embodiment. The detection circuit 41 is a bridge circuit in which four magnetoresistive elements 21 to 24 are bridge-connected. Each of the first to fourth magnetoresistive elements 21 to 24 is a strip-shaped thin film pattern disposed along the conductor 2, and the first to fourth magnetoresistive elements 21 to 24 correspond to the induction magnetic field Hm generated by the detection target current Im flowing through the conductor 2. The resistance value indicates a change.

  Specifically, the resistance values of the first and third magnetoresistive elements 11 and 13 change in the same direction according to the induction magnetic field Hm to be detected, that is, increase or decrease. On the other hand, the resistance values of the second and fourth magnetoresistive elements 12 and 14 are opposite to the changes in the resistance values of the first and third magnetoresistive elements 11 and 13 according to the induction magnetic field Hm. Change in orientation, ie decrease or increase. For example, when the resistance values of the first and third magnetoresistive elements 11 and 13 are increased, the resistance values of the second and fourth magnetoresistive elements 12 and 14 are decreased. Yes.

  In the detection circuit 41 of the current sensor of the present embodiment, one ends of the first and second magnetoresistive elements are connected at the first connection point P1, and one ends of the third and fourth magnetoresistive elements are connected. Connected at the second connection point P2, the other end of the first magnetoresistance effect element 21 and the other end of the fourth magnetoresistance effect element 24 are connected at the third connection point P3, and the second magnetoresistance A bridge circuit is formed by connecting the other end of the effect element 22 and the other end of the third magnetoresistance effect element 23 at the fourth connection point P4, and the first and third magnetoresistance effect elements are formed. The resistance values of the second and fourth magnetoresistive elements change in the same direction according to the induced magnetic field Hm to be detected, and the resistance values of the second and fourth magnetoresistance effect elements are both the first and third magnetic fields according to the induced magnetic field Hm. Changes in the opposite direction to the resistive element It has become to so that.

  In the detection circuit 41 of the current sensor of the present embodiment, when a voltage is applied between the first connection point P1 and the second connection point P2 in the first to fourth magnetoresistance effect elements 21 to 24. Based on the compensation current Id generated by the potential difference between the third connection point P3 and the fourth connection point P4, a compensation magnetic field Hd in the direction opposite to the induced magnetic field Hm is applied to each of the magnetoresistive effect elements 21 to 24. Since the compensation current line 30 is provided, the change in the output voltage due to the variation in characteristics between the four magnetoresistive elements, the variation in the connection resistance, or the temperature variation is cancelled.

  As shown in FIG. 9, the detection circuit 41 has connection points P1 to P4. Each connection point P1 to P4 is a thin film pattern made of a nonmagnetic material having a high conductivity such as Cu. The connection point P1 is connected to the power source Vcc, and the connection point P2 is grounded. Furthermore, the connection points P3 and P4 are both connected to the input side of the differential amplifier AMP.

  One end of the compensation current line 30 is connected to the output side of the differential amplifier AMP through a wiring (not shown), and the other end is grounded via the resistor RL. Compensation current detection means S is connected at the end to the differential amplifier AMP side of the resistor RL. As a result, the compensation current line 30 is supplied with a compensation current Id based on a potential difference between the connection point P3 and the connection point P4 when a voltage is applied between the connection point P1 and the connection point P2. It becomes. The compensation current line 30 has a path that applies a compensation magnetic field Hd to the first to fourth magnetoresistive elements 21 to 24 when the compensation current Id flows.

  The compensation magnetic field Hd generated in the band-shaped compensation current line pair 35 constituting the compensation current line 30 is in the opposite direction to the induced magnetic field Hm generated by the detection target current Im flowing through the conductor 2. That is, as indicated by the arrows in FIG. 9, when the induction magnetic field Hm is applied to the first to fourth magnetoresistive elements 21 to 24, for example, in the + X direction, the compensation magnetic field Hd is applied in the -X direction. Is done.

  A method for obtaining the detection target current Im by measuring the induced magnetic field Hm using the current sensor of the present embodiment will be described. In FIG. 9, first, let us consider a state in which the induction magnetic field Hm and the compensation magnetic field Hd are not applied. Here, the resistance values in the first to fourth magnetoresistance effect elements 21 to 24 when the read current I0 is supplied from the power supply Vcc are r1 to r4.

Read current I0 from power supply Vcc is divided into two at read point I1 and read current I2 at connection point P1. After that, the read current I1 that has passed through the first magnetoresistive element 21 and the fourth magnetoresistive element 24, and the read current that has passed through the second magnetoresistive element 22 and the third magnetoresistive element 23 I2 joins at the connection point P2. In this case, the potential difference V between the connection point P1 and the connection point P2 is
V = I1 * r4 + I1 * r1 = I2 * r3 + I2 * r2
= I1 (r4 + r1) = I2 (r3 + r2) (1)
It can be expressed as.

The potential V1 at the third connection point P3 and the potential V2 at the fourth connection point P4 are respectively
V1 = V-V4
= V-I1 * r4
V2 = V-V3
= V-I2 * r3
It can be expressed. Therefore, the potential difference V0 between the third connection point P3 and the fourth connection point P4 is
V0 = V2-V1
= (V-I2 * r3)-(V-I1 * r4)
= I1 * r4-I2 * r3 (2)
Here, V0 = r4 / (r4 + r1) × V−r3 / (r3 + r2) × V from the equation (1).
= {R4 / (r4 + r1) -r3 / (r3 + r2)} * V (3)
It becomes.

In this bridge circuit, when the induction magnetic field Hm is applied, the resistance change amount is obtained by measuring the voltage V0 between the connection point P3 and the connection point P4 represented by the above equation (3). . Here, when the induction magnetic field Hm is applied, if the resistance values r1 to r4 increase by the change amounts ΔR1 to ΔR4, that is, the resistance values r1 to r4 when the induction magnetic field Hm is applied, respectively.
R1 = r1 + ΔR1
R2 = r2 + ΔR2
R3 = r3 + ΔR3
R4 = r4 + ΔR4
If the induced magnetic field Hm is applied, the potential difference V0 when the induction magnetic field Hm is applied is expressed by the following equation (3):
V0 = {(r4 + ΔR4) / (r4 + ΔR4 + r1 + ΔR1) + (r3 + ΔR3) / (r3 + ΔR3 + r2 + ΔR2)} × V (4)
It becomes.

  As already described, in this current sensor, the resistance values R1 and R3 of the first and third magnetoresistance effect elements 21 and 23 and the resistance values R2 and R4 of the second and fourth magnetoresistance effect elements 22 and 24 are described. Change in the opposite direction, the change amount ΔR3 and the change amount ΔR2 cancel each other, and the change amount ΔR4 and the change amount ΔR1 cancel each other. For this reason, when comparing before and after application of the induction magnetic field Hm, there is almost no increase in the denominator in each term of the equation (4).

  On the other hand, for the numerator of each term, since the change amount ΔR3 and the change amount ΔR4 always have opposite signs, the increase and decrease appear without canceling each other. When the induction magnetic field Hm is applied, the resistance values of the second and fourth magnetoresistive elements 22 and 24 change by the amount of change ΔR2, ΔR4 (ΔR2, ΔR4 <0), respectively (substantially). On the other hand, in the first and third magnetoresistive elements 21 and 23, the resistance values change by the amount of change ΔR1, ΔR3 (ΔR1, ΔR3> 0), that is, increase substantially. Because. Therefore, if the first to fourth magnetoresistive elements 21 to 24 whose relation between the external magnetic field and the resistance change amount are known are used, the magnitude of the induced magnetic field Hm can be measured. The magnitude of the detection target current Im that generates the magnetic field Hm can be estimated.

  However, in general, the resistance values r1 to r4 and the change amounts ΔR1 to ΔR4 are different from each other due to individual differences between the first to fourth magnetoresistance effect elements 21 to 24, and variations in connection resistance in the circuit. The potential difference V includes an error component due to the above-described factors. Therefore, in this current sensor, the error component of the potential difference V is removed using the compensation magnetic field Hd. Specifically, in this current sensor, the potential V1 detected at the connection point P3 and the potential V2 detected at the connection point P4 are supplied to the differential amplifier AMP so that the difference, that is, the potential difference V0 becomes zero. Compensation current Id is output.

  The compensation current Id from the differential amplifier AMP is a compensation current line 30 arranged corresponding to the first to fourth magnetoresistive elements 21 to 24, respectively, and is a first to fourth strip-like compensation current line pair 31. To 34 in a direction opposite to the detection target current Im, thereby generating a compensation magnetic field Hd in a direction opposite to the induced magnetic field Hm. This compensation magnetic field Hd is an error component caused by variations in connection resistance in the circuit, variations in characteristics among the first to fourth magnetoresistive elements 21 to 24, temperature fluctuations, external disturbance magnetic fields, and the like. Acts to cancel. For this reason, the compensation current Id approaches a magnitude proportional to only the induction magnetic field Hm as a result.

  Therefore, by measuring the output voltage Vout in the compensation current detection means S and calculating the compensation current Id from the relationship with the known resistor RL, the induced magnetic field Hm can be obtained more accurately, and consequently the current to be detected The magnitude of Im can be estimated with high accuracy. As shown in FIG. 11, the first to fourth magnetoresistive elements 21 to 24 exhibit nonlinearity with respect to an external magnetic field. By forming such a full bridge circuit, nonlinearity is achieved. The effect of showing the characteristics, that is, the output error can be canceled, and high-precision measurement is possible.

  The present embodiment is not limited to the above-described embodiment and the like, and various modifications are possible. For example, in the above-described embodiment and the like, the case where the detection target current is detected using the detection circuit including the four magnetoresistive elements has been described, but the present embodiment is not limited to this. For example, a detection circuit 42 in which the magnetoresistive effect elements 21 and 22 in FIG. 9 are replaced with constant current sources 81 and 82 as in the modification based on the circuit in FIG. 9 shown in FIG. 13 is used. May be. Furthermore, a detection circuit in which the magnetoresistive elements 21 and 22 in FIG. 9 are replaced with resistors may be used.

(Evaluation)
FIG. 10 shows a calculation result of the compensation magnetic field Hd distribution generated on the surface where the magnetoresistive effect element 20 exists by the comparative example shown in FIG. 14 and the compensation current line 30 of the present embodiment. Since the band-shaped compensation current line pairs in FIG. 5 and the like are arranged across the X axis, the compensation magnetic field Hd is distributed in the X axis direction. Accordingly, in FIG. 10, the arbitrary arrangement in the X-axis direction is set to 0, and the positional relationship is on the horizontal axis, and the vertical axis indicates the magnitude of the compensation magnetic field Hd. The width of the compensation current line 30 = 8 μm, the thickness = 5.5 μm, the pitch of each line = 14 μm, the distance between the upper surface of the first current line 301 and the magnetoresistive element surface = 2 μm (solenoid type only), second The distance between the lower surface of the current line 302 and the magnetoresistive element surface was calculated as 0.5 μm. According to FIG. 10, it was confirmed that the magnitude of the magnetic field generated on the magnetoresistive effect element surface was almost doubled by adopting the solenoid shape of the present embodiment.

  FIG. 11 shows a magnetoresistive effect element bridge circuit when the compensation current Id is applied to the magnetic sensor element 1 in which only the shape of the compensation current line 300 of the comparative example shown in FIG. 14 is changed to the solenoid shape of this embodiment. Shows the output. Due to the difference in the amount of generated magnetic field shown in FIG. 10, the gradient of the output / compensation current in the vicinity of zero current is greatly different. As a result, it was verified that by using the solenoid type compensation current line according to the present embodiment, the compensation current can be reduced and the power consumption during the current sensor operation can be reduced.

12 shows the film thickness of the insulating film separating the band-shaped compensation current line pair 35 constituting the compensation current line 30 of the present embodiment and the magnetoresistive effect element 20, and the band-shaped compensation current line pair 35 and the magnetoresistive effect. The relationship of the breakdown voltage by the voltage difference between the elements 20 is shown. FIG. 12 shows the results when Al ₂ O ₃ is used as the insulating film, the magnetoresistive effect element width = 10 μm, the compensation current line width = 6 μm, and the 35 current sensor elements 10 per film thickness of each insulating film. As a result of examining the breakdown voltage, the minimum breakdown voltage indicates that the film thickness of Al ₂ O ₃ is saturated at 500 nm. In addition, when the insulating film thickness is 300 nm or less, there is a possibility that dielectric breakdown may occur at about the operating voltage of the full bridge circuit formed by the magnetoresistive effect element. Thus, it was verified that the insulating film needs to be thick enough not to be destroyed by the voltage difference generated between the compensation current line 30 and the magnetoresistive effect element 20.

DESCRIPTION OF SYMBOLS 1 Magnetic sensor element 10 Magnetic sensor 2 Conductor 3 Electrode 4 Intermediate electrode 5 Substrate 6 Shield structure 7 1st connection conductor
9 Permanent magnet 15 Second connecting conductor 100, 1000 Current sensor 20 Magnetoresistive element 21-24 First to fourth magnetoresistive element 30, 300 Compensation current line 301 First current line 302 Second current line 31 34 First to fourth strip-shaped compensation current line pairs 310 to 340 First to fourth strip-compensation current lines 35 Band-compensation current line pairs 41 and 42 Detection circuit 60 Stack 61 Fixed layer 62 Intermediate layer 63 Free layer 64 Magnetization fixed Film 65 Antiferromagnetic film 66 Protective film 81, 82 Current source

Claims (16)

A substrate,
A magnetoresistive effect element whose resistance value changes according to an external magnetic field formed on the substrate;
A compensation current line for applying a compensation magnetic field in a direction different from the external magnetic field to the magnetoresistive effect element by flowing a compensation current;
The compensation current lines are arranged in parallel so as to sandwich the magnetoresistive effect element through an insulating film from a second direction opposite to the first direction and the first direction. Including a second current line and a first connection conductor connecting the first and second current lines in series;
The range obtained by projecting the first and second current lines and the magnetoresistive effect element in the normal direction of the substrate has a region that overlaps in the entire longitudinal direction of the magnetoresistive effect element,
The magnetic sensor element, wherein the compensation current flows through the first and second current lines in an antiparallel direction along a longitudinal direction of the magnetoresistive element.   2. The magnetic sensor element according to claim 1, wherein the insulating film that is 10 times or more the film thickness of the magnetoresistive effect element is provided between the magnetoresistive effect element and the compensation current line.   The magnetic sensor element according to claim 1, wherein the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film exceeds 300 nm.   The magnetic sensor element according to claim 3, wherein the insulating film is an insulating material of group 3 or group 4 atoms, and the film thickness of the insulating film is 500 nm or more. A substrate,
A magnetoresistive effect element whose resistance value changes according to an external magnetic field formed on the substrate;
A compensation current line for applying a compensation magnetic field in a direction different from the external magnetic field to the magnetoresistive effect element by flowing a compensation current;
The compensation current lines are arranged in parallel so as to sandwich the magnetoresistive effect element through an insulating film from a second direction opposite to the first direction and the first direction. Including a second current line and a first connection conductor connecting the first and second current lines in series;
The range obtained by projecting the first and second current lines and the magnetoresistive effect element in the normal direction of the substrate has a region that overlaps in the entire longitudinal direction of the magnetoresistive effect element,
The compensation current flows in the antiparallel direction along the longitudinal direction of the magnetoresistive effect element through the first and second current lines,
The magnetoresistive effect element includes a pinned layer having a magnetization direction fixed in a fixed direction, an intermediate layer, and a free layer whose magnetization direction changes according to an external magnetic field,
The magnetic sensor element according to claim 1, wherein the magnetization direction of the pinned layer is a direction orthogonal to an extending direction of the compensation current line.   The magnetic sensor element according to claim 5, further comprising a permanent magnet that applies a bias magnetic field in a direction orthogonal to the magnetization direction of the pinned layer.   6. The magnetic sensor element according to claim 5, wherein the insulating film having a thickness 10 times or more of the thickness of the magnetoresistive effect element is provided between the magnetoresistive effect element and the compensation current line.   6. The magnetic sensor element according to claim 5, wherein the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film exceeds 300 nm.   The magnetic sensor element according to claim 8, wherein the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film is 500 nm or more. A substrate,
A magnetoresistive effect element whose resistance value changes according to an external magnetic field formed on the substrate;
A compensation current line for applying a compensation magnetic field in a direction different from the external magnetic field to the magnetoresistive effect element by flowing a compensation current;
The compensation current lines are arranged in parallel so as to sandwich the magnetoresistive effect element through an insulating film from a second direction opposite to the first direction and the first direction. Including a second current line and a first connection conductor connecting the first and second current lines in series;
The range obtained by projecting the first and second current lines and the magnetoresistive effect element in the normal direction of the substrate has a region that overlaps in the entire longitudinal direction of the magnetoresistive effect element,
The compensation current flows in the antiparallel direction along the longitudinal direction of the magnetoresistive effect element through the first and second current lines,
A plurality of second connection conductors on the opposite side of the first connection conductor across the first and second current lines, and a plurality of the magnetoresistive elements,
The plurality of magnetoresistive elements are arranged in parallel in a third direction different from the extending direction of the compensation current line,
The plurality of compensation currents flowing in the first and second current lines respectively provided in the plurality of magnetoresistive effect elements flow in an antiparallel direction along a longitudinal direction of the plurality of magnetoresistive effect elements. A magnetic sensor element in which first and second current lines included in the magnetoresistive effect element are connected by the plurality of first and second connection conductors. As the magnetoresistive effect element, the first to fourth magnetoresistive effect elements are provided,
One ends of the first and second magnetoresistance effect elements are connected at a first connection point, one ends of the third and fourth magnetoresistance effect elements are connected at a second connection point, and the first The other end of the first magnetoresistive element and the other end of the fourth magnetoresistive element are connected at a third connection point, and the other end of the second magnetoresistive element and the third magnetoresistive element A bridge circuit is formed by connecting the other end of the effect element at the fourth connection point,
The compensation current is generated by a potential difference between the third connection point and the fourth connection point when a voltage is applied between the first connection point and the second connection point. Yes,
The resistance values of the first and third magnetoresistive elements change in the same direction according to the external magnetic field,
The resistance value of each of the second and fourth magnetoresistive elements changes in the opposite direction to the first and third magnetoresistive elements in accordance with the external magnetic field. The magnetic sensor element according to 10. The magnetoresistive effect element includes a pinned layer having a magnetization direction fixed in a fixed direction, an intermediate layer, and a free layer whose magnetization direction changes according to an external magnetic field,
The magnetic sensor element according to claim 10, wherein the magnetization direction of the pinned layer is a direction orthogonal to an extending direction of the compensation current line.   The magnetic sensor element according to claim 12, further comprising a permanent magnet that applies a bias magnetic field in a direction orthogonal to the magnetization direction of the pinned layer.   11. The magnetic sensor element according to claim 10, wherein the insulating film that is 10 times or more the film thickness of the magnetoresistive effect element is provided between the magnetoresistive effect element and the compensation current line.   The magnetic sensor element according to claim 10, wherein the insulating film is an insulating material of a group 3 or group 4 atom, and the film thickness of the insulating film exceeds 300 nm. The magnetic sensor element according to claim 15, wherein the insulating film is an insulating material of group 3 or group 4 atoms, and the film thickness of the insulating film is 500 nm or more.

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