JP5171933B2 - Magnetic sensor - Google Patents

Description

  The present invention relates to a magnetic sensor excellent in disturbance magnetic field and strong magnetic field resistance.

  A magnetic sensor using a magnetoresistive effect element can be used as a geomagnetic sensor that detects geomagnetism incorporated in a portable device such as a mobile phone.

  Patent Document 1 discloses an invention relating to a magnetic sensor including a magnetoresistive element. For example, Patent Document 1 discloses a magnetic sensor having a magnetoresistive element and a permanent magnet layer. The magnetization direction of the free magnetic layer constituting the magnetoresistive element is aligned in one direction by the bias magnetic field from the permanent magnet layer.

  By the way, the magnetic sensor must have excellent resistance against a disturbance magnetic field from a direction orthogonal to the sensitivity axis direction of the magnetoresistive effect element. Nowadays, it is required to expand the applicable magnetic field range with respect to the disturbance magnetic field more than ever.

  However, in the invention described in Patent Document 1, no particular countermeasure is taken against disturbance magnetic field resistance.

  In addition, when a strong magnetic field is applied from a direction orthogonal to the magnetization direction of the permanent magnet layer, the magnetization direction of the permanent magnet layer is inclined, causing a midpoint potential shift of the magnetic sensor.

JP 2006-66821 A

  The present invention is intended to solve the above-described conventional problems, and in particular, an object of the present invention is to provide a magnetic sensor that is superior in disturbance magnetic field and strong magnetic field resistance as compared with conventional ones.

The magnetic sensor in the present invention is
A magnetoresistive effect element comprising an element portion that exhibits a magnetoresistive effect, and a permanent magnet layer for supplying a bias magnetic field to the element portion;
In the element part, the first element part and the second element part are alternately arranged in the first horizontal direction in a plan view,
The permanent magnet layer is disposed between the first element part and the second element part,
Soft magnetic bodies that are not in contact with the magnetoresistive effect element are disposed on both sides in a second horizontal direction orthogonal to the first horizontal direction with respect to the magnetoresistive effect element in plan view,
The second horizontal direction is a sensitivity axis direction of the element unit,
Each permanent magnet layer is magnetized in the second horizontal direction, and a first bias magnetic field directed in the first horizontal direction is supplied from the permanent magnet layer to the first element portion, and A second bias magnetic field in a direction opposite to the first bias magnetic field is supplied to the two element portions. Thereby, it can be set as the structure excellent in the disturbance magnetic field and the strong magnetic field tolerance conventionally.

  In the present invention, end faces of the permanent magnet layers facing the first element part and the second element part in a plan view are formed obliquely with respect to the first horizontal direction and the second horizontal direction. It is preferable. Thereby, bias magnetic fields in opposite directions can be supplied to the first element portion and the second element portion.

In the present invention, the magnetoresistive effect element includes a plurality of element connection bodies in which the first element part, the second element part, and the permanent magnet layer are connected in the first horizontal direction in a plan view. The second horizontal direction is arranged with an interval, and the end of each element continuous body is formed in a meander shape electrically connected,
It is preferable that the soft magnetic material is disposed between the element connection bodies and outside the element connection bodies located on both sides in the second horizontal direction. Thereby, the shielding effect with respect to the disturbance magnetic field by a soft magnetic body and the sensitivity magnetic field amplification effect can be improved with respect to each element continuous body formed in a meander shape.

In the present invention, the element portion has a laminated structure in which a pinned magnetic layer and a free magnetic layer are laminated via a nonmagnetic material layer,
In the pinned magnetic layer, a first magnetic layer and a second magnetic layer in contact with the nonmagnetic material layer are laminated via a nonmagnetic intermediate layer, and the first magnetic layer and the second magnetic layer are antiparallel. A self-pinning type in which magnetization is fixed is preferable. In the self-pinning type magnetoresistive effect element, the first magnetic layer and the second magnetic layer constituting the pinned magnetic layer can be pinned in an antiparallel manner without using an antiferromagnetic layer and without performing a heat treatment in a magnetic field.

  In the present invention, a bridge circuit is configured by the four magnetoresistive effect elements, and each magnetoresistive effect element has a sensitivity axis direction of two magnetoresistive effect elements and a sensitivity axis of the remaining two magnetoresistive effect elements. The self-pinned magnetoresistive effect element is preferably composed of a direction opposite to the direction. By using a self-pinned magnetoresistive element, a plurality of magnetoresistive elements having different sensitivity axis directions can be formed on the same substrate.

  According to the present invention, a magnetic sensor excellent in disturbance magnetic field and strong resistance as compared with the prior art can be obtained.

FIG. 1A is a plan view showing a configuration of a part of the magnetic sensor in the present embodiment, and FIG. 1B is a magnetic view cut along the line AA shown in FIG. Partial longitudinal section of the sensor, The partial top view of the magnetoresistive effect element which consists of meander shape in this embodiment, FIG. 1 is a partially enlarged plan view showing a part of the magnetoresistive effect element shown in FIG. A circuit diagram of a magnetic sensor in the present embodiment, The partial top view of the magnetoresistive effect element which shows another structure in this embodiment, 6A is a partial longitudinal sectional view of the magnetoresistive effect element taken along the line BB shown in FIG. 1 and viewed from the arrow direction. FIGS. 6B and 6C are modified examples thereof. Partial enlarged vertical sectional view of the element portion in the present embodiment, Explanatory drawing of the disturbance magnetic field tolerance with respect to the magnetic sensor of this embodiment.

  FIG. 1A is a plan view showing a configuration of a part of the magnetic sensor in the present embodiment, and FIG. 1B is a magnetic view cut along the line AA shown in FIG. 2 is a partial longitudinal sectional view of the sensor, FIG. 2 is a partial plan view of a magnetoresistive effect element having a meander shape in the present embodiment, and FIG. 3 is an enlarged view of a part of the magnetoresistive effect element shown in FIG. 4 is an enlarged plan view, FIG. 4 is a circuit diagram of the magnetic sensor in the present embodiment, FIG. 5 is a partial plan view of a magnetoresistive effect element showing another configuration in the present embodiment, and FIG. 6A is shown in FIG. FIGS. 7A and 7B are partial vertical cross-sectional views of the magnetoresistive effect element cut along the line BB and viewed from the arrow direction. FIGS. 7B and 7C are modified examples thereof, and FIGS. FIG.

  The magnetic sensor 10 provided with the magnetoresistive effect element in the present embodiment is configured as a geomagnetic sensor mounted on a portable device such as a mobile phone.

  The X direction and the Y direction shown in each figure indicate two directions orthogonal to each other in the horizontal plane, and the Z direction indicates a direction orthogonal to the horizontal plane. One of the X direction and the Y direction is the “first horizontal direction”, and the other is the “second horizontal direction”.

  As shown in FIG. 4, the magnetic sensor 10 forms a bridge circuit with four magnetoresistive elements 13a to 13d.

  As shown in FIG. 4, the magnetoresistive effect element 13a and the magnetoresistive effect element 13b are connected in series, and the magnetoresistive effect element 13c and the magnetoresistive effect element 13d are connected in series. As shown in FIG. 4, the magnetoresistive effect element 13a and the magnetoresistive effect element 13c are connected to the input terminal Vdd, and the magnetoresistive effect element 13b and the magnetoresistive effect element 13d are connected to the ground terminal GND. Output terminals V1 and V2 are connected between the magnetoresistive effect element 13a and the magnetoresistive effect element 13b and between the magnetoresistive effect element 13c and the magnetoresistive effect element 13d, respectively.

  [P] shown in FIG. 4 indicates the sensitivity axis direction, and the sensitivity axis direction P of the magnetoresistive effect element 13a and the magnetoresistive effect element 13d is the same direction, but the sensitivity with the magnetoresistive effect elements 13b and 13c. The axial direction P is directed in the opposite direction with respect to the magnetoresistive effect element 13a and the magnetoresistive effect element 13d. The sensitivity axis direction P indicates the fixed magnetization direction of the fixed magnetic layer described later.

  As shown in FIG. 1, the magnetoresistive elements on the left side of the figure are the magnetoresistive elements 13a and 13d shown in FIG. 4, and the magnetoresistive elements on the right side of the figure are the magnetoresistive elements 13b and 13c shown in FIG. In each of the magnetoresistive elements 13a to 13d, the configuration other than the sensitivity axis direction P is the same.

  As shown in FIG. 1, each of the magnetoresistive elements 13 a to 13 d includes an element unit 15 that exhibits a magnetoresistive effect and a plurality of permanent magnet layers 14 that supply a bias magnetic field to the element unit 15. . The permanent magnet layer 14 is made of CoPt, CoPtCr, or the like.

  Each magnetoresistive effect element 13a-13d shown to Fig.1 (a) is long extended in the Y1-Y2 direction, and is formed.

  As shown in FIG. 1B, the magnetoresistive elements 13 a to 13 d are formed on the substrate 29 via an insulating layer 30.

As shown in FIG. 1A, each of the magnetoresistive elements 13a to 13d includes a plurality of first element portions 15a and a plurality of second element portions 15b alternately in a plan view of FIG. The structure is arranged with an interval in the Y1-Y2 direction.
And the permanent magnet layer 14 is arrange | positioned between each element part 15a, 15b.

  Each of the magnetoresistive effect elements 13a to 13d shown in FIG. 1A has a single element connection body 17 in which a plurality of element portions 15a and 15b and a plurality of permanent magnet layers 14 are connected in the Y1-Y2 direction. In actuality, as shown in FIG. 2, a plurality of element connecting bodies 17 are arranged at intervals in the X1-X2 direction, and the Y1 side end portions 17a of each element connecting body 17 are arranged together. Alternatively, the Y2 side end portions 17b are electrically connected through the conductive layer 18 to form a meander shape. 2 does not show the permanent magnet layer 14 shown in FIG.

As shown in FIG. 7, the element portion 15 is formed by laminating the seed layer 2, the pinned magnetic layer 3, the nonmagnetic material layer 4, the free magnetic layer 5, and the protective layer 6 in this order from the bottom. Each layer constituting the magnetic detection element 1 is formed by sputtering, for example.
The seed layer 2 is formed of NiFeCr or Cr.

  The pinned magnetic layer 3 has an SFP (Synthetic Ferri Pin) structure of a first magnetic layer 3a, a second magnetic layer 3c, and a nonmagnetic intermediate layer 3b interposed between the first magnetic layer 3a and the second magnetic layer 3c. .

  As shown in FIG. 7, the fixed magnetization direction (P1) of the first magnetic layer 3a and the fixed magnetization direction (P2) of the second magnetic layer 3c are antiparallel.

  As shown in FIG. 7, the first magnetic layer 3a is formed on the seed layer 2, and the second magnetic layer 3c is formed in contact with a nonmagnetic material layer 4 described later.

  The first magnetic layer 3a in the present embodiment is preferably formed of an FeCo alloy that is a higher coercive force material than the second magnetic layer 3c.

  The second magnetic layer 3c in contact with the nonmagnetic material layer 4 is a layer that contributes to the magnetoresistive effect (GMR effect). The second magnetic layer 3c has an average of conduction electrons having up spins and conduction electrons having down spins. A magnetic material capable of increasing the free path difference is selected.

  In the configuration shown in FIG. 7, the difference between the magnetization amounts (saturation magnetization Ms and film thickness t) of the first magnetic layer 3a and the second magnetic layer 3c is adjusted to be substantially zero.

  The pinned magnetic layer 3 in this embodiment is a self-pinning type having an SFP structure. That is, the antiferromagnetic layer is not provided, so that the temperature characteristics of the element portion 15 are not restricted by the blocking temperature of the antiferromagnetic layer.

  In order to increase the magnetization pinning force of the pinned magnetic layer 3, the coercive force Hc of the first magnetic layer 3a is increased, and the difference in magnetization between the first magnetic layer 3a and the second magnetic layer 3c is adjusted to substantially zero. In addition, it is important to adjust the film thickness of the nonmagnetic intermediate layer 3b to increase the antiparallel coupling magnetic field due to the RKKY interaction generated between the first magnetic layer 3a and the second magnetic layer 3c.

  The nonmagnetic material layer 4 is made of Cu (copper) or the like. Moreover, although the free magnetic layer 5 shown in FIG. 7 is comprised by the laminated structure of the CoFe alloy layer 5a and the NiFe alloy layer 5b, it is not limited to this. The protective layer 6 is Ta (tantalum) or the like.

  In the element unit 15 shown in FIG. 7, the fixed magnetization direction (P2) of the second magnetic layer 3c is the X2 direction, and the fixed magnetization direction (P2) of the second magnetic layer 3c is the fixed magnetization in the fixed magnetic layer 3. Direction, that is, the sensitivity axis direction. Therefore, the element part 15 shown in FIG. 7 is an element part which comprises the magnetoresistive effect elements 13a and 13d shown in FIG. On the other hand, by directing the fixed magnetization direction (P1) of the first magnetic layer 3a shown in FIG. 7 in the X2 direction and the fixed magnetization direction (P2) of the second magnetic layer 3c in the X1 direction, the magnetoresistance shown in FIG. The element portions 15 of the effect elements 13b and 13c can be configured.

  In the embodiment shown in FIG. 1A, the plurality of permanent magnet layers 14 are formed in a substantially trapezoidal shape (a shape in which the trapezoid is tilted horizontally). As shown in FIG. 1A, each permanent magnet layer 14 is disposed between the element portions 15a and 15b spaced from each other in the Y1-Y2 direction.

  Here, as shown in FIG. 1A, among the permanent magnet layers 14, the permanent magnet layers 14a, 14c, and 14e are arranged in the same direction, and these permanent magnet layers 14a, 14c, and 14e are , Arranged in the same position in the Y1-Y2 direction. Further, the permanent magnet layers 14b and 14d are arranged in a direction in which the permanent magnet layers 14a, 14c and 14e are inverted 180 degrees in a plane. The permanent magnet layers 14b and 14d are arranged at the same position in the Y1-Y2 direction. The permanent magnet layers 14a, 14c, 14e and the permanent magnet layers 14b, 14d are arranged slightly shifted in the X1-X2 direction.

  As shown in the partially enlarged plan view of FIG. 3, each permanent magnet layer 14 has end faces 14f, 14g, 14h, and 14i that face the element portions 15a and 15b in a plan view, respectively, in the X1-X2 direction and the Y1-Y2 direction. It is formed obliquely with respect to both. Here, the end surfaces 14g and 14h of the permanent magnet layer 14b and the permanent magnet layer 14c facing each other are formed substantially in parallel with a space therebetween, and the end surfaces of the permanent magnet layer 14c and the permanent magnet layer 14d facing each other are formed. 14i and 14f are formed substantially in parallel with a space therebetween. A first element portion 15a is disposed between the permanent magnet layer 14b and the permanent magnet layer 14c, and a second element portion 15b is disposed between the permanent magnet layer 14c and the permanent magnet layer 14d. The regions other than those shown in FIG. 3 are formed in the same manner as described above.

  As shown in FIG. 3, for example, each permanent magnet layer 14b, 14c, 14d is magnetized in the X2 direction. In FIG. 3, the magnetization direction is indicated by a thick arrow C.

  As shown in FIG. 3, the first bias magnetic field HB1 is generated from the end surface 14h on the Y2 side of the permanent magnet layer 14c toward the end surface 14g on the Y1 side of the permanent magnet layer 14b. A second bias magnetic field HB2 is generated from the side surface 14i on the Y1 side of the permanent magnet layer 14c toward the end surface 14f on the Y2 side of the permanent magnet layer 14d. As shown in FIG. 3, the first bias magnetic field HB1 is generated in the Y2 direction, and the second bias magnetic field HB2 is generated in the Y1 direction.

  Therefore, the first bias magnetic field HB1 is supplied to the first element portion 15a, and the second bias magnetic field HB2 is supplied to the second element portion 15b. The first bias magnetic field HB1 and the second bias magnetic field HB2 are in opposite directions and are orthogonal to the fixed magnetization direction (sensitivity axis direction) P of the fixed magnetic layer 3.

  As described above, the magnetization direction of the free magnetic layer 5 of the first element unit 15a is aligned with the Y2 direction, and the magnetization direction of the free magnetic layer 5 of the second element unit 15b is aligned with the Y1 direction.

  As shown in the longitudinal sectional view of FIG. 6A, the element portion 15 is formed on the substrate 29 via the insulating layer 30. FIG. 6A shows a structure of the element portion 15 in which the first element portion 15a and the second element portion 15b are integrated. An insulating layer 31 is provided on the element portion 15 so as to fill the space between the element continuous bodies 17 shown in FIG. 2. The insulating layer 31 is also formed on the element portion 15 to form a flat surface.

  As shown in FIG. 6A, each permanent magnet layer 14 is formed on the planarized surface of the insulating layer 31. The first element portions 15a and the second element portions 15b appear alternately between the permanent magnet layers 14.

  In FIG. 6A, an insulating layer 31 is interposed between the element portion 15 and the permanent magnet layer 14, but such a configuration has an element continuous body in which the permanent magnet layer 14j is adjacent to each other as shown in FIG. This is applied to a form shared by 17. Therefore, when the permanent magnet layer is not shared between the adjacent element continuous bodies and the permanent magnet layer is separated by each element continuous body, the insulating layer 31 is not necessary, and the permanent magnet layer is directly and directly on the element portion 15. The magnet layer 14 can be formed.

  Or as shown in FIG.6 (b), a part of element part 15 may be removed and the permanent magnet layer 14 may be formed on the removed recessed part 15c. For example, the protective layer 6, the free magnetic layer 5, and the nonmagnetic material layer 4 shown in FIG.

  Alternatively, as shown in FIG. 6C, all the element portions 15 at the position where the permanent magnet layer 14 is formed are deleted to separate the first element portion 15a and the second element portion 15b, and the first element portion 15a. The permanent magnet layer 14 may be interposed between the second element portion 15b and the second element portion 15b.

  6B and 6C, the insulating layer 31 is not interposed between the element portion 15 and the permanent magnet layer 14 as shown in FIG. 6A, but the permanent magnet layer 14 is connected to adjacent elements. In the case of sharing between the bodies 17, the insulating layer 31 is necessary as in FIG.

  As shown in FIG.1 (b), each magnetoresistive effect element 13a-13d is covered with the insulating layer 32, and the upper surface of the insulating layer 32 is made into the planarization surface.

  A soft magnetic material 33 is disposed on the insulating layer 32 on both sides in the X1-X2 direction of the magnetoresistive elements 13a to 13d in the plan view of FIG. Each soft magnetic body 33 is formed to extend parallel to the Y1-Y2 direction. It is preferable that the length dimension L1 in the Y1-Y2 direction of each soft magnetic body 33 is formed longer than each magnetoresistive effect element 13a-13d. As shown in FIG. 1B, the soft magnetic bodies 33 and the magnetoresistive elements 13 a to 13 d are not in contact with each other through the insulating layer 32.

  As shown in FIG. 2, when the magnetoresistive effect element has a meander shape with a plurality of element connecting bodies 17, the soft magnetic body 33 is between the element connecting bodies 17 and in the X1-X2 direction in plan view. Are respectively provided on the outer sides of the element connecting bodies 17 located on both sides.

  Each soft magnetic body 33 is formed of NiFe, CoFe, CoFeSiB, CoZrNb, or the like.

  Next, resistance changes of the magnetoresistive elements 13a to 13d when an external magnetic field from the sensitivity axis direction and a disturbance magnetic field from a direction orthogonal to the sensitivity axis direction are described.

  The sensitivity axis direction of each of the magnetoresistive effect elements 13a to 13d is the X1-X2 direction. For example, as shown in FIG. 1A, when the external magnetic field H1 acts in the X2 direction, the magnetization direction of the free magnetic layer 5 changes from the Y1-Y2 direction to the X2 direction. Since the pinned magnetization direction (P) of the pinned magnetic layer 3 of the magnetoresistive effect elements 13a and 13d is the X2 direction, the electric resistance value decreases when the magnetization direction of the free magnetic layer 5 changes in the X2 direction. On the other hand, since the pinned magnetization direction (P) of the pinned magnetic layer 3 of the magnetoresistive effect elements 13b and 13c is the X1 direction, the electric resistance value increases when the magnetization direction of the free magnetic layer 5 changes in the X2 direction. Therefore, the midpoint potential of the output terminals V1 and V2 in the bridge circuit shown in FIG. 4 varies, and a sensor output can be obtained.

  Next, as shown in FIG. 1A, when the disturbance magnetic field H2 acts in the Y2 direction orthogonal to the sensitivity axis direction, the magnetization direction F of the free magnetic layer 5 of the first element portion 15a is the same as that described in FIG. Since the Y2 direction is directed by the one bias magnetic field HB1, the magnetization of the free magnetic layer 5 in the first element portion 15a is caused by the disturbance magnetic field H2 (note that the disturbance magnetic field H2 acting on the element portion 15 is a soft magnetic body 33 described later). It is strengthened by a smaller effect due to the shielding effect). When the external magnetic field H1 acts in the sensitivity axis direction (X1-X2) in the state where the disturbance magnetic field H2 is applied in this way, the change in electric resistance in the first element portion 15a becomes smaller than in the state where there is no disturbance magnetic field H2 ( See also Fig. 8. The resistance change (or ΔMR) in the first element portion 15a corresponds to the disturbance magnetic field (+) graph of Fig. 8).

  On the other hand, since the magnetization direction of the free magnetic layer 5 in the second element portion 15b is the Y1 direction by the second bias magnetic field HB2 described in FIG. 3, the magnetization of the free magnetic layer 5 in the second element portion 15b is It is weakened by the disturbance magnetic field H2. When the external magnetic field H1 acts in the sensitivity axis direction (X1-X2) in the state where the disturbance magnetic field H2 is applied in this way, the electrical resistance change in the second element portion 1b becomes larger than in the state where there is no disturbance magnetic field H2 ( See also Fig. 8. The resistance change (or ΔMR) in the second element portion 15b corresponds to the disturbance magnetic field (-) graph of Fig. 8).

  As described above, in this embodiment, when the disturbance magnetic field H2 is applied, the magnetoresistive effect elements 13a to 13d are provided with an element portion in which the magnetization of the free magnetic layer 5 is strengthened and an element portion in which the magnetization of the free magnetic layer 5 is weakened. Therefore, due to the mutual canceling effect, the disturbance magnetic field H2 does not act on the resistance change in the entire magnetoresistive effect elements 13a to 13d as compared with the conventional structure in which the magnetization direction of the free magnetic layer is aligned in one direction. It can approach the resistance change in the state.

  In the present embodiment, in addition to the element configuration of the magnetoresistive effect elements 13a to 13d, the soft magnetic body 33 is provided on both sides of the magnetoresistive effect elements 13a to 13d in the X1-X2 direction. As a result, the soft magnetic body 33 can function as a shield layer against the disturbance magnetic field H2. For this reason, the disturbance magnetic field H2 can be preferentially passed through the soft magnetic body 33, the disturbance magnetic field H2 affecting the magnetoresistive effect elements 13a to 13d can be reduced, and the above-described canceling effect can be sufficiently exhibited. Can be made. In other words, without relying on the soft magnetic material 33 and relying only on the cancellation effect described above, the stronger the disturbance magnetic field, the greater the deviation of the cancellation effect, leading to a reduction in disturbance magnetic field resistance. Therefore, in this embodiment, by providing the soft magnetic body 33, the disturbance magnetic field H2 that affects the magnetoresistive elements 13a to 13d is reduced, and the above-described canceling effect is effectively exhibited to improve the disturbance magnetic field resistance. It is letting me.

  Further, as shown in FIGS. 1A and 3, the direction of the disturbance magnetic field H2 is orthogonal to the magnetization direction C of the permanent magnet layer 14, but even if a strong magnetic field acts from the orthogonal direction, soft magnetic Due to the shielding effect of the body 33, the change in the magnetization direction C of the permanent magnet layer 14 can be reduced, and the midpoint potential shift due to the change in the magnetization direction C of the permanent magnet layer 14 can be reduced.

  As described above, excellent disturbance magnetic field and strong magnetic field resistance can be obtained, and the applicable magnetic field range of the disturbance magnetic field can be expanded as compared with the conventional case.

  Further, by arranging the soft magnetic bodies 33 on both sides of the magnetoresistive effect elements 13a to 13d in the X1-X2 direction, it has a magnetic field amplification effect on the external magnetic field H1 from the sensitivity axis direction (X1-X2). That is, an external magnetic field that is apparently stronger than the external magnetic field H1 can be applied to the element portion 15. Therefore, even if the thickness of the permanent magnet layer 14 is increased or the material is changed to increase the amount of bias magnetization of the permanent magnet layer 14, excellent sensor sensitivity can be maintained due to the magnetic field amplification effect. Is possible.

  By increasing the amount of bias magnetization of the permanent magnet layer 14 in this way, it is possible to more effectively improve the resistance against a disturbance magnetic field, particularly a strong magnetic field.

  The shape of the permanent magnet layer 14 is not limited to that shown in FIGS. However, as shown in FIG. 3, the end surfaces 14g and 14i on the Y1 side and the end surfaces 14f and 14h on the Y2 side of the permanent magnet layers 14b to 14d are inclined with respect to both the X1-X2 direction and the Y1-Y2 direction. It is preferable that the bias magnetic fields HB1 and HB2 oriented in the Y1-Y2 direction can be appropriately supplied to the first element portion 15a and the second element portion 15b.

  Further, in the configuration in which each magnetoresistive effect element 13a to 13d is formed in a meander shape by a plurality of element connecting bodies 17 as shown in FIG. 2, for example, as shown in FIG. By providing the permanent magnet layer 14j to be shared, a simple configuration can be achieved and downsizing can be realized. However, in such a case, as described with reference to FIG. 6A, an insulating layer 31 is provided between the permanent magnet layer 14 and the element portion 15 so that the sense current is adjacent to the element via the permanent magnet layer 14 (14j). It is necessary not to flow into the continuous body 17.

  As shown in FIG. 2, in the configuration in which the magnetoresistive elements 13a to 13d are formed in the meander shape by the element connecting body 17, the element connecting positions located between the element connecting bodies 17 and on both sides in the X1-X2 direction are provided. By disposing the soft magnetic bodies 33 on the outside of the body 17, it is possible to obtain a shielding effect against a disturbance magnetic field and a sensitivity magnetic field amplification effect by the soft magnetic bodies 33 with respect to all the element connecting bodies 17.

  Although the pinned magnetic layer 3 is a self-pinning type in FIG. 7, it is not limited to this. That is, a method of fixing the magnetization direction of the pinned magnetic layer 3 using an antiferromagnetic layer may be used.

  However, by adopting the self-pinning type, no heat treatment in a magnetic field is required, and therefore the magnetoresistive effect elements 13a to 13d having different fixed magnetization directions (P) of the fixed magnetic layer 3 are formed on the same substrate as shown in FIG. Can be formed. That is, when the magnetoresistive effect elements 13a and 13b and the magnetoresistive effect elements 13b and 13c are formed on the substrate, they may be formed while applying reverse magnetic fields to each other. Further, in FIG. 1A, all the permanent magnet layers 14 constituting the magnetoresistive effect elements 13a to 13d can be magnetized in the X2 direction.

  The sensitivity axis direction of the magnetic sensor 10 shown in FIG. 1 is the X1-X2 direction. By rotating the magnetic sensor 10 shown in FIG. 1 by 90 degrees in the plane, the sensitivity axis direction is oriented in the Y1-Y2 direction. The X-axis-Y-axis magnetic sensor can be configured easily and appropriately.

H1 external magnetic field H2 disturbance magnetic field HB1 first bias magnetic field HB2 second bias magnetic field 3 pinned magnetic layer 4 nonmagnetic material layer 5 free magnetic layer 10 magnetic sensors 13a to 13d magnetoresistive effect element 14 permanent magnet layer 15a first element portion 15b first 2 element part 17 element connection body 33 soft magnetic body

Claims (5)

A magnetoresistive effect element comprising an element portion that exhibits a magnetoresistive effect, and a permanent magnet layer for supplying a bias magnetic field to the element portion;
In the element part, the first element part and the second element part are alternately arranged in the first horizontal direction in a plan view,
The permanent magnet layer is disposed between the first element part and the second element part,
Soft magnetic bodies that are not in contact with the magnetoresistive effect element are disposed on both sides in a second horizontal direction orthogonal to the first horizontal direction with respect to the magnetoresistive effect element in plan view,
The second horizontal direction is a sensitivity axis direction of the element unit,
Each permanent magnet layer is magnetized in the second horizontal direction, and a first bias magnetic field directed in the first horizontal direction is supplied from the permanent magnet layer to the first element portion, and A magnetic sensor, wherein a second bias magnetic field in a direction opposite to the first bias magnetic field is supplied to the two element portions.   The end surface of each permanent magnet layer facing the first element portion and the second element portion in plan view is formed obliquely with respect to the first horizontal direction and the second horizontal direction. Magnetic sensor. The magnetoresistive effect element includes a plurality of element connecting bodies in which the first element part, the second element part, and the permanent magnet layer are connected in the first horizontal direction in a plan view. It is arranged in the horizontal direction at intervals, and is formed in a meander shape in which the end portions of each element connecting body are electrically connected,
3. The magnetic sensor according to claim 1, wherein the soft magnetic body is disposed between the element connection bodies and outside the element connection bodies located on both sides in the second horizontal direction. The element portion includes a laminated structure in which a pinned magnetic layer and a free magnetic layer are laminated via a nonmagnetic material layer,
In the pinned magnetic layer, a first magnetic layer and a second magnetic layer in contact with the nonmagnetic material layer are laminated via a nonmagnetic intermediate layer, and the first magnetic layer and the second magnetic layer are antiparallel. 4. The magnetic sensor according to claim 1, wherein the magnetic sensor is a self-pinned type in which magnetization is fixed.   A bridge circuit is formed by the four magnetoresistive effect elements, and each magnetoresistive effect element has a sensitivity axis direction of two magnetoresistive effect elements opposite to a sensitivity axis direction of the remaining two magnetoresistive effect elements. The magnetic sensor according to claim 4, wherein the magnetic sensor is constituted by the self-pinned magnetoresistive effect element.

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