JP2019074481A - Magnetic sensor - Google Patents

Abstract

To increase the detection accuracy of a magnetic sensor constituted by four bridge-connected magnetosensitive elements.SOLUTION: The present invention comprises a magnetic substance layer 40 provided on the surface of a sensor substrate 20 and bridge-connected magnetosensitive elements R1-R4. The magnetic substance layer 40 includes areas 41-46 each of which is rectangular. The area 41 is sandwiched between the areas 43, 45, and the area 42 is sandwiched between the areas 44, 46. The magnetosensitive element R1 is arranged on a magnetic path formed by a gap G1 located between the areas 41, 43, the magnetosensitive element R2 is arranged on a magnetic path formed by a gap G2 located between the areas 42, 46, the magnetosensitive element R3 is arranged on a magnetic path formed by a gap G3 located between the areas 42, 46, and the magnetosensitive element R4 is arranged on a magnetic path formed by a gap G4 located between the areas 41, 45. According to the present invention, a magnetic flux generated by a current flowing in each magnetosensitive element does not affect the other magnetosensitive elements, so that detection accuracy is increased.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a magnetic sensor, and more particularly to a magnetic sensor in which four magnetic sensing elements are bridge-connected.

  Magnetic sensors using magnetosensitive elements are widely used in ammeters and magnetic encoders. As described in Patent Document 1, the magnetic sensor may be provided with an external magnetic body for collecting a magnetic flux in the magnetosensitive element. However, in the magnetic sensor described in Patent Document 1, it is difficult to improve detection accuracy because the magnetic flux to be detected is not sufficiently concentrated on the magnetosensitive element.

  On the other hand, in the magnetic sensor described in Patent Document 2, a magnetic layer is provided on a sensor substrate on which a magnetosensitive element is formed, and thereby the magnetic flux to be detected is concentrated on the magnetosensitive element. In the magnetic sensor described in Patent Document 2, three magnetic layers are used to form two gaps, and two magnetosensitive elements are disposed in each of the two gaps, for a total of four magnetosensitive elements. Make up a bridge circuit.

Patent No. 5500785 Patent No. 4964301

  However, in the magnetic sensor described in Patent Document 2, since the number of gaps formed by the magnetic layer is two, the two magnetic sensing elements constituting the bridge circuit are arranged in the same gap. become. The current flowing through these two magnetic sensing elements is in such a relationship that as one decreases, the other increases, so that the magnetic flux generated by the current flowing through one of the magnetic sensing elements exerts a significant influence on the other magnetic sensing element. As a result, there was a possibility that detection accuracy might fall.

  Therefore, an object of the present invention is to provide an improved magnetic sensor in which four magnetic sensing elements are bridge-connected.

  The magnetic sensor according to the present invention comprises a sensor substrate, a magnetic layer provided on the sensor substrate, and first to fourth magnetic sensing elements bridge-connected, and each of the magnetic layers is rectangular. The first to sixth regions are provided, the first region is provided to be sandwiched between the third and fifth regions, and the second region is interposed between the fourth and sixth regions. And the first magnetic sensing element is disposed on the magnetic path formed by the first gap located between the first region and the third region, and the second magnetic sensing element is The third magnetosensitive element is disposed on the magnetic path formed by the second gap located between the second region and the sixth region, and the third magnetosensitive element is located between the second region and the fourth region. The fourth magnetic sensing element is disposed between the first area and the fifth area, disposed on the magnetic path formed by the three gaps. Characterized in that it is arranged on a magnetic path formed by the fourth gap.

  According to the present invention, since the four magnetic sensing elements are disposed on the magnetic path formed by the mutually different gaps, the magnetic flux generated by the current flowing in each magnetic sensing element affects the other magnetic sensing elements. There is no This makes it possible to provide a magnetic sensor with higher detection accuracy. In addition, since the regions constituting the magnetic layer are rectangular, it is also possible to suppress Barkhausen noise that is noticeable when the magnetic layer has a complicated shape. In addition, since the size of each of the magnetic sensing elements can be sufficiently secured, it is also possible to obtain a high S / N ratio.

  The magnetic sensor according to the present invention may further include a first external magnetic body provided on the sensor substrate so as to cover the first and second regions of the magnetic layer. According to this, the selectivity of the magnetic flux in the direction perpendicular to the sensor substrate can be enhanced.

  In this case, the width of the first external magnetic body in the first direction, which is the extending direction of the first to fourth gaps, is the total width of the first and second regions of the magnetic layer in the first direction. It is wider than this, so that the full width in the first direction of the first and second regions may be covered by the first external magnetic material. According to this, it is possible to suppress a decrease in detection accuracy caused by the positional displacement of the first external magnetic body.

  The magnetic sensor according to the present invention comprises a second external magnetic body provided in the vicinity of the third and fourth regions of the magnetic layer and a fifth external magnetic body provided in the vicinity of the fifth and sixth regions of the magnetic layer. It may further comprise three external magnetic bodies. According to this, it is possible to obtain higher detection accuracy.

  In the present invention, the first region and the second region of the magnetic layer may be integral and rectangular as a whole. Also, the third and fourth regions of the magnetic layer are integral and generally rectangular, and the fifth and sixth regions of the magnetic layer are integral and generally It may be rectangular. According to these, it is possible to further simplify the planar shape of the magnetic layer.

  In the present invention, the first magnetosensitive element overlaps the first and third regions of the magnetic layer, and the second magnetosensitive device includes the second and sixth regions of the magnetic layer. And the third magnetosensitive element overlaps the second and fourth regions of the magnetic layer, and the fourth magnetosensitive element includes the first and second magnetic layers of the magnetic layer. It may overlap with the fifth region. According to this, since the leakage magnetic flux is reduced, it is possible to obtain higher detection accuracy.

  In the present invention, the magnetic layer may be provided with a notch having a loop-like outer periphery. According to this, since the residual magnetic flux of the magnetic layer circulates around the outer periphery of the notch portion, it is possible to prevent a decrease in detection accuracy due to the residual magnetic flux.

  In the present invention, the first, second, third and fourth magnetosensitive elements are each a plurality of magnetosensitive elements disposed on the magnetic path formed by the first, second, third and fourth gaps, respectively. May be connected in series. According to this, it is possible to obtain higher detection accuracy.

  In this case, the magnetic layer further has a seventh region arranged between the plurality of magnetosensitive elements which respectively constitute the first, second, third and fourth magnetosensitive elements in plan view. It does not matter. According to this, it is possible to reduce the leakage flux between the plurality of magnetic sensing elements. Furthermore, in this case, the seventh region of the magnetic layer may overlap with a plurality of magnetic sensing elements constituting the first, second, third and fourth magnetic sensing elements. According to this, it is possible to further reduce the leakage flux between the plurality of magnetic sensing elements. The seventh region of the magnetic layer may be divided in a first direction which is the extending direction of the first to fourth gaps. According to this, since the seventh region of the magnetic layer has magnetic anisotropy, it is possible to obtain higher detection accuracy.

  In the present invention, all of the first to fourth magnetosensitive devices are preferably magnetoresistive devices. In this case, it is preferable that the sensitivity directions of the magnetoresistance elements constituting the first to fourth magnetosensitive elements are identical to each other, and the magnetoresistance elements constituting the first to fourth magnetosensitive elements are spin valve type. It is preferably a GMR element.

  According to the present invention, since the four magnetic sensing elements are disposed on the magnetic path formed by the different gaps, the magnetic sensing element having high detection accuracy is configured by bridge-connecting the four magnetic sensing elements. It becomes possible.

FIG. 1 is a schematic perspective view showing the appearance of a magnetic sensor 100 according to a preferred embodiment of the present invention. FIG. 2 is a schematic exploded perspective view of the magnetic sensor 100. As shown in FIG. FIG. 3 is a schematic cross-sectional view taken along the line A-A shown in FIG. FIG. 4 is a schematic plan view for explaining the structure of the element forming surface 21 of the sensor substrate 20. As shown in FIG. FIG. 5 is a schematic cross-sectional view taken along the line B-B shown in FIG. FIG. 6 is a circuit diagram for explaining the connection between the magnetosensitive elements R1 to R4 and the bonding pads 51 to 54. As shown in FIG. FIG. 7 is a schematic cross-sectional view for illustrating the configuration of the main part of the magnetic sensor 101 according to the first modification. FIG. 8 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 102 according to a second modification. FIG. 9 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 103 according to a third modification. FIG. 10 is a schematic cross-sectional view for illustrating the configuration of the main part of the magnetic sensor 104 according to the fourth modification. FIG. 11 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 105 according to a fifth modification. FIG. 12 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 106 according to the sixth modification. FIG. 13 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 107 according to a seventh modification. FIG. 14 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 108 according to the eighth modification. FIG. 15 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 109 according to the ninth modification. FIG. 16 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 110 according to a tenth modification. FIG. 17 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 111 according to an eleventh modification. FIG. 18 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 112 according to a twelfth modification. FIG. 19 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 113 according to a thirteenth modification. FIG. 20 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 114 according to a fourteenth modification. FIG. 21 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 115 according to a fifteenth modification. FIG. 22 is a schematic cross-sectional view for explaining a modification of the magnetic sensor 115. As shown in FIG. FIG. 23 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 116 according to a sixteenth modification. FIG. 24 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 117 according to a seventeenth modification. FIG. 25 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 118 according to the eighteenth modification. FIG. 26 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 119 according to a nineteenth modification. FIG. 27 is a schematic perspective view for describing a configuration of a main part of a magnetic sensor 120 according to a twentieth modification.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic perspective view showing the appearance of a magnetic sensor 100 according to a preferred embodiment of the present invention. 2 is a schematic exploded perspective view of the magnetic sensor 100, and FIG. 3 is a schematic cross-sectional view along the line A-A shown in FIG.

  As shown in FIGS. 1 to 3, the magnetic sensor 100 according to the present embodiment includes a circuit board 10 having an opening 11, a sensor board 20 disposed in the opening 11, and a first fixed to the sensor board 20. The fourth to fourth external magnetic members 31 to 34 are provided. The sensor substrate 20 is a chip component smaller than the circuit substrate 10, and has a magnetosensitive element described later. The first to fourth external magnetic members 31 to 34 are blocks made of a soft magnetic material having high permeability such as ferrite.

  The sensor substrate 20 has a substantially rectangular parallelepiped shape, and the first external magnetic body 31 is disposed on the element forming surface 21 constituting the xy plane. As a method of manufacturing the sensor substrate 20, a method of simultaneously forming a large number of sensor substrates 20 on a collective substrate and separating a large number of them is generally used, but the present invention is not limited thereto. Alternatively, individual sensor substrates 20 may be separately manufactured. Although details will be described later, four magnetosensitive elements R <b> 1 to R <b> 4 and a magnetic layer 40 are formed on the element forming surface 21. Further, four bonding pads 51 to 54 are provided on the element forming surface 21 and are connected to the bonding pads 61 to 64 provided on the circuit substrate 10 via the corresponding bonding wires BW.

  Furthermore, the second and third external magnetic members 32 and 33 are disposed on both sides of the sensor substrate 20 in the x direction. The second and third external magnetic members 32 and 33 are connected through the fourth external magnetic member 34 located at the bottom of the sensor substrate 20, whereby the second to fourth external magnetic members 32 to 32 are formed. 34 constitute a single magnetic block 35. The magnetic block 35 is disposed to be inserted into the opening 11 of the circuit board 10. The magnetic block 35 is provided with a recess 36 for accommodating the sensor substrate 20. When the sensor substrate 20 is accommodated in the recess 36, the element forming surface 21 of the sensor substrate 20, and the second and third The tips of the external magnetic members 32 and 33 are close to one another, and constitute substantially the same plane.

  Next, each component formed on the element forming surface 21 of the sensor substrate 20 will be described in detail.

  FIG. 4 is a schematic plan view for explaining the structure of the element forming surface 21 of the sensor substrate 20. As shown in FIG. 5 is a schematic cross-sectional view taken along the line B-B shown in FIG.

  As shown in FIGS. 4 and 5, the magnetic material layer 40 is formed on the element forming surface 21 of the sensor substrate 20. Although not particularly limited, the magnetic layer 40 may be a film made of a composite magnetic material in which a magnetic filler is dispersed in a resin material, a thin film made of a soft magnetic material such as nickel or permalloy, or It may be a foil, or it may be a thin film or a bulk sheet made of ferrite or the like.

  In the present embodiment, the magnetic layer 40 is divided into first to fourth regions 41 to 46. Each of the first area 41 to the sixth area 46 has a rectangular shape, and two sides thereof extend in the x direction, and the remaining two sides extend in the y direction. Among these, the first region 41 and the second region 42 are disposed substantially at the center of the element forming surface 21 in the x direction, and are adjacent to each other in the y direction. In addition, the third area 43 and the fifth area 45 are provided on both sides of the first area 41 in the x direction, whereby the first area 41 becomes the third area 43 and the fifth area. 45 are sandwiched in the x direction. Similarly, a fourth area 44 and a sixth area 46 are provided on both sides of the second area 42 in the x direction, whereby the second area 42 is a fourth area 44 and a sixth area. Region 46 is sandwiched in the x direction. The third area 43 and the fourth area 44 are adjacent to each other in the y direction, and similarly, the fifth area 45 and the sixth area 46 are adjacent to each other in the y direction.

  Although not particularly limited, the width of the first external magnetic body 31 in the y direction is wider than the total width of the first and second regions 41 and 42 of the magnetic layer 40 in the y direction. Preferably, the entire width in the y direction of the first and second regions 41 and 42 is covered by the first external magnetic body 31. According to this, even if a deviation occurs in the relative positional relationship between the first external magnetic body 31 and the magnetic body layer 40 at the time of manufacture, the detection accuracy does not significantly decrease. As the positional deviation, in addition to the deviation in the xy direction, rotational deviation is also conceivable.

  Here, the first region 41 and the second region 42 of the magnetic layer 40 have the same shape and size as each other, and are line symmetrical with an imaginary straight line L1 extending in the x direction as an axis of symmetry. is there. Due to such a symmetrical shape, the magnetic flux taken in via the first external magnetic body 31 is distributed substantially equally to the first region 41 and the second region 42 of the magnetic layer 40. In addition, the first and second regions 41 and 42 are arranged so as to be axisymmetrical with the imaginary straight line L2 extending in the y direction as the axis of symmetry.

  In addition, the third region 43 and the fourth region 44 of the magnetic layer 40 have the same shape and size as each other, and are line symmetrical with the virtual straight line L1 extending in the x direction as the axis of symmetry. . Due to such a symmetrical shape, the magnetic flux taken in via the second external magnetic body 32 is distributed substantially equally to the third and fourth regions 43 and 44 of the magnetic body layer 40. Similarly, the fifth region 45 and the sixth region 46 of the magnetic layer 40 have the same shape and size as each other, and are line symmetrical with respect to a virtual straight line L1 extending in the x direction as an axis of symmetry. is there. Due to such a symmetrical shape, the magnetic flux taken in via the third external magnetic body 33 is distributed substantially equally to the fifth and sixth regions 45 and 46 of the magnetic layer 40. In addition, the third and fourth regions 43 and 44 and the fifth and sixth regions 45 and 46 are arranged so as to be line symmetrical with respect to a virtual straight line L2 extending in the y direction as a symmetry axis. .

  One end of the first region 41 in the x direction is opposed to one end of the third region 43 in the x direction via the first gap G1. Further, the other end of the first region 41 in the x direction is opposed to one end of the fifth region 45 in the x direction via the fourth gap G4. Similarly, one end of the second region 42 in the x direction is opposed to one end of the fourth region 44 in the x direction via the third gap G3. Further, the other end of the second region 42 in the x direction is opposed to one end of the sixth region 46 in the x direction via the second gap G2. As described above, since each of the regions 41 to 46 is rectangular, the length of the end portion of each of the regions 41 to 46 in the y direction is substantially the same as the width of the region in the y direction.

  As shown in FIG. 4, first to fourth magnetosensitive elements R1 to R4 extending in the y direction are arranged in the first to fourth gaps G1 to G4, respectively. The widths in the x direction of the first to fourth gaps G1 to G4 are the same. The first to fourth magnetosensitive elements R1 to R4 are not in contact with the magnetic layer 40.

  The magnetosensitive elements R1 to R4 are not particularly limited as long as the physical properties change according to the magnetic flux density, but are preferably magnetoresistance elements whose electric resistance changes according to the direction of the magnetic field, and the spin valve type GMR element Is particularly preferred. In the present embodiment, the sensitivity directions (fixed magnetization directions) of the magnetosensitive elements R1 to R4 are all aligned in the direction indicated by the arrow C in FIGS. 4 and 5 (plus side in the x direction).

  As shown in FIG. 5, the first external magnetic body 31 plays the role of collecting the magnetic flux φ in the z direction and discharging it to the first and second regions 41 and 42 of the magnetic layer 40. The height of the first external magnetic body 31 in the z direction is not particularly limited, but the selectivity of the magnetic flux in the z direction can be enhanced by increasing the height in the z direction. However, if the height of the first external magnetic body 31 in the z direction is too high, the support of the first external magnetic body 31 may become unstable, so it is high in the range where stable support can be ensured. It is preferable to do.

  The magnetic flux φ collected in the first and second regions 41 and 42 of the magnetic layer 40 through the first external magnetic body 31 is substantially equally distributed to the first and second regions 41 and 42. Then, the light is emitted to the third to sixth regions 43 to 46 through the first to fourth magnetosensitive elements R1 to R4, respectively. As a result, magnetic flux in opposite directions is applied to the magnetosensitive elements R1 and R3 and the magnetosensitive elements R2 and R4. As described above, since the magnetization fixed direction of the magnetosensitive elements R1 to R4 is oriented in the x plus direction indicated by the arrow C, it has sensitivity to the component of the magnetic flux in the x direction.

  The magnetic flux reaching the third and fourth regions 43 and 44 of the magnetic layer 40 is collected by the second external magnetic body 32. Similarly, the magnetic flux reaching the fifth and sixth regions 45 and 46 of the magnetic layer 40 is collected by the third external magnetic body 33.

  FIG. 6 is a circuit diagram for explaining the connection between the magnetosensitive elements R1 to R4 and the bonding pads 51 to 54. As shown in FIG.

  As shown in FIG. 6, the ground potential Gnd and the power supply potential Vdd are supplied to the bonding pads 51 and 54, respectively, from the circuit board 10 side. The magnetosensitive elements R1 and R2 are connected in series between the bonding pads 51 and 54, and the magnetosensitive elements R4 and R3 are connected in series. The connection point of the magnetosensitive elements R3 and R4 is connected to the bonding pad 52, and the connection point of the magnetosensitive elements R1 and R2 is connected to the bonding pad 53. By referring to the potential Va appearing on the bonding pad 53 and the potential Vb appearing on the bonding pad 52 by such a bridge connection, changes in the electrical resistance of the magnetosensitive elements R1 to R4 according to the magnetic flux density can be detected with high sensitivity. It becomes possible.

  Specifically, since all of the magnetic sensing elements R1 to R4 have the same magnetization fixing direction, the amount of change in resistance of the magnetic sensing elements R1 and R3 located on one side with respect to the first external magnetic body 31 There is a difference between the amount of change in resistance of the magnetosensitive elements R2 and R4 located on the other side with respect to the first external magnetic body 31. This difference is doubled by the differential bridge circuit shown in FIG. 6 and appears on the bonding pads 52 and 53. The circuit board 10 is provided with a voltage detection circuit (not shown), and by detecting the difference between the potentials Va and Vb appearing on the bonding pads 52 and 53, it becomes possible to measure the magnetic flux density.

  In the magnetic sensor 100 according to the present embodiment, the magnetic body layer 40 is provided on the element forming surface 21 of the sensor substrate 20, and the magnetosensitive elements R1 are provided in the four gaps G1 to G4 provided in the magnetic body layer 40, respectively. Since ~ 4 are arranged, the magnetic flux generated by the current flowing to a certain magnetic sensing element does not affect other magnetic sensing elements. This makes it possible to obtain higher detection accuracy than in the prior art.

  In addition, since the regions 41 to 46 constituting the magnetic layer 40 are rectangular, it is also possible to suppress Barkhausen noise that is noticeable when the magnetic layer has a complicated shape. Further, since the lengths of the magnetosensitive elements R1 to R4 in the y direction can be sufficiently secured, it is also possible to obtain a high S / N ratio.

  Moreover, since the magnetic sensor 100 according to the present embodiment includes the first external magnetic body 31, the magnetic flux in the z direction can be selectively detected. Moreover, in the magnetic sensor 100 according to the present embodiment, since the second external magnetic body 32 and the third external magnetic body 33 are integrated, the magnetic resistance of the magnetic flux flowing around behind the sensor substrate 20 is reduced. You can also.

  Hereinafter, some modifications of the magnetic sensor 100 according to the present embodiment will be described.

  FIG. 7 is a schematic cross-sectional view for illustrating the configuration of the main part of the magnetic sensor 101 according to the first modification. In the example shown in FIG. 7, the insulating layers 22 and 23 are stacked in this order on the surface of the sensor substrate 20, and the surface of the insulating layer 22 constitutes the element forming surface 21. The magnetosensitive elements R1 to R4 are provided on the surface of the insulating layer 22 which is the element forming surface 21, and the magnetic layer 40 is provided on the surface of the insulating layer 23 located on the upper layer. As described above, in the magnetic sensor 101 according to the first modification, the magnetosensitive elements R1 to R4 and the magnetic layer 40 are located in different layers, and the first and third regions 41 and 43 of the magnetic layer 40 are formed. The magnetosensitive element R1 is disposed at a position overlapping with the gap G1 formed by the above in plan view, and it is felt at a position overlapping with the gap G4 formed by the first and fifth regions 41 and 45 of the magnetic layer 40 in plan view. A magnetic element R4 is disposed. The same applies to the magnetosensitive elements R2 and R3. As illustrated by the magnetic sensor 101 according to the first modification, in the present invention, the positions of the magnetosensitive elements R1 to R4 and the magnetic layer 40 in the z direction may be different from each other. In this case, although the magnetosensitive elements R1 to R4 are not strictly located between the gaps G1 to G4, they are disposed on the magnetic path formed by the gaps G1 to G4, so the magnetic flux passing through the gaps G1 to G4 Can be detected correctly.

  FIG. 8 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 102 according to a second modification. In the example shown in FIG. 8, a part of the magnetosensitive element R1 overlaps the first and third regions 41 and 43 of the magnetic layer 40 in the z direction, and a part of the magnetosensitive element R4 is magnetic. The first and fifth regions 41 and 45 of the body layer 40 overlap in the z direction. The same applies to the magnetosensitive elements R2 and R3. Also in this example, the magnetosensitive elements R1 to R4 are not strictly located between the gaps G1 to G4, but are disposed on the magnetic path formed by the gaps G1 to G4. As described above, when the positions of the magnetosensitive elements R1 to R4 and the magnetic material layer 40 in the z direction are different from each other, leakage magnetic flux can be obtained by disposing parts of them in the z direction in the vicinity of the gaps G1 to G4. Since it is reduced, it is possible to obtain higher detection accuracy.

  FIG. 9 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 103 according to a third modification. In the example illustrated in FIG. 9, the insulating layers 24, 25, and 26 are stacked in this order on the surface of the sensor substrate 20, and the surface of the insulating layer 25 constitutes the element forming surface 21. The magnetosensitive elements R1 to R4 are provided on the surface of the insulating layer 25 which is the element forming surface 21, and the third to sixth regions 43 to 46 of the magnetic layer 40 are provided on the surface of the insulating layer 24 located in the lower layer. The first and second regions 41 and 42 of the magnetic layer 40 are provided on the surface of the insulating layer 26 which is provided and located in the upper layer. Thus, in the magnetic sensor 103 according to the third modification, the first and second regions 41 and 42 and the third to sixth regions 43 to 46 are located in different layers, and some of these are Three-dimensional gaps G1 to G4 are formed by overlapping. The magnetosensitive elements R1 to R4 are arranged between the gaps G1 to G4. As exemplified by the magnetic sensor 103 according to the third modification, the gaps G1 to G4 do not have to be planar, and may be three-dimensional.

  FIG. 10 is a schematic cross-sectional view for illustrating the configuration of the main part of the magnetic sensor 104 according to the fourth modification. In the example shown in FIG. 10, the first and second regions 41 and 42 and the third to sixth regions 43 to 46 of the magnetic layer 40 are located in different layers, and overlap each other. Absent. Therefore, gaps G1 to G4 in the oblique direction are formed by the first and second regions 41 and 42 and the third to sixth regions 43 to 46, and the magnetosensitive element R1 is located at a position corresponding to these gaps G1 to G4. To R4 are arranged. In this case, the magnetosensitive elements R1 to R4 and the magnetic layer 40 may or may not overlap.

  FIG. 11 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 105 according to a fifth modification. In the example shown in FIG. 11, the second external magnetic body 32 and the third external magnetic body 33 are not integrated but are separated from each other. In such a configuration, although the magnetic resistance of the magnetic flux flowing around behind the sensor substrate 20 slightly increases, substantially the same effect as the above-described magnetic sensor 100 can be obtained.

  FIG. 12 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 106 according to the sixth modification. In the example shown in FIG. 12, the second and third external magnetic members 32, 33 are omitted. In such a configuration, although the magnetic flux collecting effect by the second and third external magnetic members 32 and 33 disappears, substantially the same effect as the above-described magnetic sensor 100 can be obtained.

  FIG. 13 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 107 according to a seventh modification. In the example shown in FIG. 13, the first region 41 and the second region 42 of the magnetic layer 40 are integral and rectangular as a whole. As exemplified by the magnetic sensor 107 according to the seventh modification, in the present invention, it is not essential that the first region 41 and the second region 42 of the magnetic layer 40 are separated from each other, but both are integrated. It does not matter.

  FIG. 14 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 108 according to the eighth modification. In the example shown in FIG. 14, the third region 43 and the fourth region 44 of the magnetic layer 40 are integral and rectangular as a whole, and the fifth region 45 of the magnetic layer 40 and the Six regions 46 are integral and generally rectangular. As the magnetic sensor 108 according to the eighth modification exemplifies, in the present invention, the third area 43 and the fourth area 44 of the magnetic layer 40 and the fifth area 45 and the sixth area 46 are mutually different. It is not essential to separate, and both may be integrated.

  FIG. 15 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 109 according to the ninth modification. In the example shown in FIG. 15, the first region 41 and the second region 42 of the magnetic layer 40 are integrated and rectangular as a whole, and the third region 43 and the fourth region 44 are integrated. The fifth region 45 and the sixth region 46 of the magnetic layer 40 are integral and rectangular as a whole. According to such a configuration, since the planar shape of the magnetic layer 40 is simplified, it is possible to further reduce Barkhausen noise.

  FIG. 16 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 110 according to a tenth modification. In the example shown in FIG. 16, the magnetic layer 40 is provided with several notches 71. The notched portion 71 is an independent space pattern having a loop-like outer periphery, and each is an elliptical shape having the y direction as the long axis direction. An independent space pattern means that the outer periphery is closed. In the example shown in FIG. 16, two notches 71 are provided in each of the first and second regions 41 and 42, and one notches 71 are provided in each of the third to sixth regions 43 to 46. ing. In the first and second regions 41 and 42, the cutaway portion 71 is disposed to avoid the part covered with the first external magnetic body 31, whereby the first and second regions 41 and 42 are formed. It prevents the decrease of the magnetic collection effect. If such a notch 71 is provided, the residual magnetic flux of the magnetic layer 40 circulates around the outer periphery of the notch 71, so that it is possible to prevent a decrease in detection accuracy due to the residual magnetic flux.

  FIG. 17 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 111 according to an eleventh modification. The example shown in FIG. 17 is different from the example shown in FIG. 16 in that an island-shaped independent pattern 72 is provided in the inner diameter area of the notch 71. The independent pattern 72 is separated from the magnetic layer 40 via the notch 71. If such an independent pattern 72 is added, it is possible to minimize the increase in magnetic resistance due to the formation of the notch 71.

  FIG. 18 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 112 according to a twelfth modification. The example shown in FIG. 18 is different from the example shown in FIG. 16 in that one large notch 73 is provided in each of the first and second regions 41 and 42 of the magnetic layer 40. The notch portion 73 is also an independent space pattern having a loop-like outer periphery, and both are elliptical with the x direction as the long axis direction. Even with such a configuration, the same effect as the example shown in FIG. 16 can be obtained.

  FIG. 19 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 113 according to a thirteenth modification. The example shown in FIG. 19 is different from the example shown in FIG. 18 in that an island-shaped independent pattern 74 is provided in the inner diameter area of the notch 73. The independent pattern 74 is separated from the magnetic layer 40 via the notch 73. If such an independent pattern 74 is added, it is possible to minimize the increase in magnetic resistance due to the formation of the notches 73.

  FIG. 20 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 114 according to a fourteenth modification. In the example shown in FIG. 20, the first to fourth magnetosensitive elements R1 to R4 are respectively constituted by two magnetosensitive elements arranged in the first to fourth gaps G1 to G4. Specifically, a first magnetosensitive element R1 is formed by two magnetosensitive elements R11 and R12 connected in series, and a second magnetosensitive element R2 is formed by two magnetosensitive elements R21 and R22 connected in series. A third magnetosensitive element R3 is formed of two magnetosensitive elements R31 and R32 configured and connected in series, and a fourth magnetosensitive element R4 is formed of two magnetosensitive elements R41 and R42 connected in series ing. According to this, since a larger magnetoresistive effect can be obtained, it is possible to obtain high detection accuracy without increasing the size of the sensor substrate 20 almost at all. A seventh region 47 of the magnetic layer 40 may be added between two magnetosensitive elements (for example, R11 and R12) connected in series. In addition, each of the magnetosensitive elements R1 to R4 may be configured by three or more magnetosensitive elements connected in series.

  FIG. 21 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 115 according to a fifteenth modification. In the example shown in FIG. 21, the magnetosensitive element R1 is composed of two magnetosensitive elements R11 and R12, and a part of the magnetosensitive element R11 overlaps with the first and seventh regions 41 and 47 of the magnetic layer 40. A part of the magnetosensitive element R12 overlaps the third and seventh regions 43 and 47 of the magnetic layer 40. Here, the seventh region 47 may be formed in the same layer as the first and second regions 41 and 43, and as shown in FIG. May be formed in different layers. In the example shown in FIG. 22, the seventh region 47 is formed on the element forming surface 21 of the sensor substrate 20. The other magnetosensitive elements R2 to R4 (not shown) also have the same configuration as that of the magnetosensitive element R1. As described above, when the seventh region 47 is provided in the magnetic layer 40 and the magnetic sensing elements R1 to R4 and the magnetic layer 40 are disposed so as to overlap with each other, leakage magnetic flux is reduced. It becomes possible to obtain.

  FIG. 23 is a schematic plan view for illustrating the configuration of the main part of a magnetic sensor 116 according to a sixteenth modification. In the example shown in FIG. 23, the seventh region 47 of the magnetic layer 40 is divided into a large number in the y direction which is the extending direction of the gap G1. The same configuration is provided on the other gaps G2 to G4 not shown. As described above, if the seventh region 47 of the magnetic layer 40 is divided in the y direction, the flow of the magnetic flux through the gaps G1 to G4 is restricted in the x direction, which is the magnetic sensing direction, and almost flows in the y direction. It disappears. That is, since the magnetic anisotropy is generated by dividing the seventh region 47 of the magnetic layer 40 in the y direction, it is possible to obtain higher detection accuracy.

  FIG. 24 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 117 according to a seventeenth modification. In the example shown in FIG. 24, the magnetic layer 40 has a structure in which the film thickness is continuously reduced toward the gaps G1 to G4. According to such a configuration, since the magnetic flux is more concentrated on the first to fourth magnetosensitive elements R1 to R4, the detection accuracy can be enhanced.

  FIG. 25 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 118 according to the eighteenth modification. In the example shown in FIG. 25, there is a step structure in which the film thickness of the magnetic layer 40 becomes thinner in the vicinity of the gaps G1 to G4. Even with such a configuration, since the magnetic flux is more concentrated on the first to fourth magnetosensitive elements R1 to R4, the detection accuracy can be enhanced.

  FIG. 26 is a schematic cross-sectional view for illustrating the configuration of the main part of a magnetic sensor 119 according to a nineteenth modification. In the example shown in FIG. 26, the magnetic layer 40 has a step-like structure in which the thickness of the magnetic layer 40 gradually decreases toward the gaps G1 to G4. Even with such a configuration, since the magnetic flux is more concentrated on the first to fourth magnetosensitive elements R1 to R4, the detection accuracy can be enhanced.

  FIG. 27 is a schematic perspective view for describing a configuration of a magnetic sensor 120 according to a twentieth modification. In the example shown in FIG. 27, the sensor substrate 20 is mounted sideways on the surface of the circuit substrate 10 having the xy plane. That is, the element forming surface 21 of the sensor substrate 20 constitutes the xz plane, and the first external magnetic body 31 extends in the y direction. According to such a configuration, it is not necessary to provide the opening 11 in the circuit board 10, and it is possible to selectively detect the magnetic flux in the direction parallel to the main surface of the circuit board 10. In addition, even if the height (the length in the y direction) of the first external magnetic body 31 is increased, the support of the first external magnetic body 31 does not become unstable.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. It is needless to say that they are included in the scope.

DESCRIPTION OF SYMBOLS 10 Circuit board 11 Opening 20 Sensor board 21 Element formation surface 22-26 Insulating layer 31-34 External magnetic body 35 Magnetic block 36 Recess 40 Magnetic body layer 41 Magnetic body layer first region 42 Magnetic body layer second Region 43 Third region 44 of the magnetic layer 44 Fourth region 45 of the magnetic layer Fifth region 46 of the magnetic layer 46 Sixth region 47 of the magnetic layer Seventh regions 51 to 54 of the magnetic layer 61 to 64 bonding pads 71 and 73 notches 72 and 74 independent patterns 100 to 120 magnetic sensor BW bonding wires G1 to G4 gaps L1 and L2 straight lines R1 to R4 magnetosensitive element φ magnetic flux

Claims (15)

Sensor substrate,
A magnetic layer provided on a sensor substrate,
And first to fourth magnetic sensing elements connected in a bridge.
The magnetic layer has first to sixth regions which are all rectangular.
The first area is provided to be sandwiched between the third area and the fifth area,
The second region is provided to be sandwiched between the fourth region and the sixth region,
The first magnetic sensing element is disposed on a magnetic path formed by a first gap located between the first area and the third area.
The second magnetic sensing element is disposed on a magnetic path formed by a second gap located between the second region and the sixth region,
The third magnetic sensing element is disposed on a magnetic path formed by a third gap located between the second area and the fourth area,
The magnetic sensor according to claim 1, wherein the fourth magnetic sensing element is disposed on a magnetic path formed by a fourth gap located between the first area and the fifth area.   The magnetic sensor according to claim 1, further comprising a first external magnetic body provided on the sensor substrate so as to cover the first and second regions of the magnetic body layer.   The width of the first external magnetic body in a first direction which is the extending direction of the first to fourth gaps is the width of the first and second regions of the magnetic layer in the first direction. 3. A magnetic field according to claim 2, characterized in that the total width is wider, whereby the entire width in the first direction of the first and second regions is covered by the first external magnetic material. Sensor.   A second external magnetic body provided in the vicinity of the third and fourth regions of the magnetic layer and a third external provided in the vicinity of the fifth and sixth regions of the magnetic layer The magnetic sensor according to claim 2 or 3, further comprising a magnetic body.   The magnetic sensor according to any one of claims 1 to 4, wherein the first region and the second region of the magnetic layer are integral and rectangular as a whole. The third and fourth regions of the magnetic layer are integral and generally rectangular,
The magnetic sensor according to any one of claims 1 to 5, wherein the fifth area and the sixth area of the magnetic layer are integral and rectangular as a whole. The first magnetic sensing element overlaps the first and third regions of the magnetic layer,
The second magnetic sensing element has an overlap with the second and sixth regions of the magnetic layer,
The third magnetic sensing element has an overlap with the second and fourth regions of the magnetic layer,
The magnetic sensor according to any one of claims 1 to 6, wherein the fourth magnetic sensing element overlaps the first and fifth regions of the magnetic layer.   The magnetic sensor according to any one of claims 1 to 7, wherein the magnetic material layer is provided with a notch having a loop-like outer periphery.   In the first, second, third and fourth magnetosensitive devices, a plurality of magnetosensitive devices arranged on a magnetic path formed by the first, second, third and fourth gaps are connected in series. The magnetic sensor according to any one of claims 1 to 8, which is connected.   The magnetic layer further includes a seventh region arranged between the plurality of magnetic sensing elements constituting the first, second, third and fourth magnetic sensing elements in plan view. The magnetic sensor according to claim 9, characterized in that:   The seventh region of the magnetic layer has an overlap with the plurality of magnetic sensing elements constituting the first, second, third and fourth magnetic sensing elements, respectively. The magnetic sensor according to claim 10.   12. The magnetic sensor according to claim 10, wherein the seventh region of the magnetic layer is divided in a first direction which is an extension direction of the first to fourth gaps. .   The magnetic sensor according to any one of claims 1 to 12, wherein all of the first to fourth magnetosensitive elements are magnetoresistance elements.   The magnetic sensor according to claim 13, wherein the sensitivity directions of the magnetoresistance elements constituting the first to fourth magnetosensitive elements are the same.   15. The magnetic sensor according to claim 13, wherein the magnetoresistive element constituting the first to fourth magnetosensitive elements is a spin valve type GMR element.

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