JP2013172040A - Magnetic sensor and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic sensor capable of detecting, with a high sensitivity, a magnetic field by using soft magnetic materials arranged to face each other.SOLUTION: A magnetic sensor comprises: a magnetic element S which is formed by laminating a magnetic layer and a non-magnetic layer on a substrate 2 and which exhibits a magnetoresistance effect; a first soft magnetic material 4 which converts a first vertical magnetic field component from above into a first horizontal magnetic field component and applies the first horizontal magnetic field component to the magnetic element S; and a second soft magnetic material 5 which converts a second vertical magnetic field component from below into a second horizontal magnetic field component and applies the second horizontal magnetic field component to the magnetic element S. The magnetic element S is arranged between the first soft magnetic material 4 and the second soft magnetic material 5.

Description

  The present invention relates to a magnetic sensor that converts a magnetic flux into a direction that can be detected by a magnetic element using a soft magnetic material, and more particularly to a magnetic sensor in which the magnetic element is a magnetoresistive element.

  A magnetic sensor using a magnetic element is used as a geomagnetic sensor for detecting geomagnetism incorporated in a portable device such as a mobile phone.

  The geomagnetic sensor is configured to detect magnetic field components in the X-axis direction and the Y-axis direction orthogonal to each other in the horizontal plane and the vertical direction (Z-axis direction) orthogonal to the horizontal plane.

  However, in a magnetic sensor using a magnetic element that exhibits a magnetoresistive effect in which a magnetic layer and a nonmagnetic layer are laminated on a substrate surface, a horizontal magnetic field component parallel to the substrate surface can be detected, but the magnetic field component is Thus, the vertical magnetic field component cannot be detected.

  For this reason, in Patent Document 1, a soft magnetic material is provided in the vicinity of the magnetic element, the vertical magnetic field component from the outside is converted into a horizontal magnetic field component by the soft magnetic material, and converted into the horizontal direction. A magnetic field component in the vertical direction is detected by applying a magnetic field component to the magnetic element.

Japanese Patent Application No. 2009-274131

  In the magnetic sensor disclosed in Patent Document 1, a magnetic flux having a vertical magnetic field component from above is converged at the upper end portion of the soft magnetic body, passes through the soft magnetic body, and is removed from the lower end portion of the soft magnetic body. Is converted into a magnetic flux having a horizontal magnetic field component. However, since the magnetic flux passes through the soft magnetic body while the magnetic field component in the vertical direction is large, the conversion efficiency from the vertical magnetic field component to the horizontal magnetic field component is small.

  Further, for a magnetic flux having a vertical magnetic field component from below, a horizontal magnetic field component generated when the magnetic flux is converged at the lower end of the soft magnetic material is used. However, since the magnetic flux passes through the soft magnetic body while the magnetic field component in the vertical direction is large, the conversion efficiency from the vertical magnetic field component to the horizontal magnetic field component is small.

  Therefore, the configuration of the magnetic sensor disclosed in Patent Document 1 has a problem that the sensitivity to the vertical magnetic field component is small and the S / N ratio is small.

  An object of the present invention is to provide a magnetic sensor that detects a magnetic field with high sensitivity by using a soft magnetic material disposed oppositely.

  The magnetic sensor of the present invention includes a magnetic element that detects magnetic flux, a first soft magnetic body, and a second soft magnetic body, and the first soft magnetic body and the second soft magnetic body in a first direction. The magnetic element is disposed between the first soft magnetic body and the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the first direction. Is arranged on the opposite side.

  According to this aspect, the magnetic element side end portion of the first soft magnetic body and the magnetic element side end portion of the second soft magnetic body are arranged to face each other with the magnetic element interposed therebetween. .

  Therefore, the magnetic flux converged from the outside at the end located on the opposite side of the first soft magnetic body from the magnetic element is guided to the outside from the end of the first soft magnetic body at the magnetic element side, It passes through the magnetic element and converges to the end of the second soft magnetic body on the magnetic element side. At this time, the magnetic flux increases by converging from the outside, and the magnetic element side end of the first soft magnetic body and the magnetic element side end of the second soft magnetic body face each other. Thus, the magnetic element is detected as a large magnetic flux.

  In addition, the magnetic flux converged from the outside at the end located on the opposite side of the second soft magnetic body from the magnetic element is guided outward from the end of the second soft magnetic body on the magnetic element side, It passes through the magnetic element and converges to the end of the first soft magnetic body on the magnetic element side. At this time, the magnetic flux increases by converging from the outside, and the magnetic element side end of the first soft magnetic body and the magnetic element side end of the second soft magnetic body face each other. Thus, the magnetic element is detected as a large magnetic flux.

  Therefore, according to the present invention, it is possible to provide a magnetic sensor that detects a magnetic field with high sensitivity by using a soft magnetic material disposed oppositely.

  A magnetic element that exhibits a magnetoresistive effect on the front surface side of the substrate, a first soft magnetic material that is spaced from the magnetic element and disposed on the front surface side, and is spaced from the magnetic element and disposed on the back surface side of the substrate A second soft magnetic body, and the magnetic element is disposed between the first soft magnetic body and the second soft magnetic body in a first direction in the plane of the substrate. Preferably, the first soft magnetic body is disposed on the opposite side of the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the substrate surface.

  According to this aspect, the surface side end portion of the first soft magnetic body and the surface side end portion of the second soft magnetic body are disposed to face each other with the magnetic element interposed therebetween.

  Therefore, the magnetic flux converged from the outside at the end located on the opposite side of the surface of the first soft magnetic body is guided outward from the surface side end of the first soft magnetic body, and the magnetic It passes through the element and converges on the surface side end of the second soft magnetic body. At this time, the first vertical magnetic field component is converted into a first horizontal magnetic field component having a large horizontal component at the position of the magnetic element.

  Further, the magnetic flux converged from outside at the end located on the side opposite to the surface of the second soft magnetic body is guided outward from the surface side end of the second soft magnetic body, and the magnetic It passes through the element and converges to the surface side end of the first soft magnetic body. At this time, the second vertical magnetic field component is converted into a second horizontal magnetic field component having a large horizontal component at the position of the magnetic element.

  In this way, a magnetic sensor having a high efficiency for conversion from the first vertical magnetic field component and the second vertical magnetic field component to the horizontal magnetic field component is obtained.

Therefore, the magnetic sensor which can detect the magnetic field which is a perpendicular magnetic field component with high sensitivity using a magnetic element is enabled. Further, the S / N ratio is improved by detecting the magnetic field with high sensitivity.

  The end portion on the back surface side of the first soft magnetic body, the end portion on the front surface side of the second soft magnetic body, and the magnetic element are arranged at positions overlapping each other in the second direction. It is preferable.

  The end portions on the back surface side of the first soft magnetic body and the end portions on the front surface side of the second soft magnetic body are arranged so as to overlap each other in a direction perpendicular to the substrate, whereby each soft magnetic body Can efficiently converge the magnetic flux flowing out from each soft magnetic material. Accordingly, both the first horizontal magnetic field component and the second horizontal magnetic field component increase the horizontal magnetic field component, improve the conversion efficiency from the vertical magnetic field component to the horizontal magnetic field component, and cause the large horizontal magnetic field component to act on the magnetic element. Can do.

  It is preferable that an end portion of the first soft magnetic body that is far from the magnetic element is located farther from the substrate than an end portion of the second soft magnetic body that is closer to the magnetic element.

  The magnetic flux having the first perpendicular magnetic field component is converged on an end portion of the first soft magnetic body that is far from the magnetic element and an end portion of the second magnetic body that is close to the magnetic element. Therefore, the end portion of the first soft magnetic body on the side far from the magnetic element is located farther from the substrate than the end portion of the second soft magnetic body on the side close to the magnetic element. The magnetic body preferentially converges the magnetic flux having the first perpendicular magnetic field component over the second soft magnetic body. As a result, the magnetic flux having the first vertical magnetic field component converged on the first soft magnetic body is increased, the first horizontal magnetic field component converted from the first vertical magnetic field component is increased, and a large horizontal magnetic field component is obtained. Can be obtained.

  It is preferable that an end portion of the second soft magnetic body that is far from the magnetic element is located farther from the substrate than an end portion of the first soft magnetic body that is closer to the magnetic element.

  The magnetic flux having the second perpendicular magnetic field component is converged on the end portion of the first soft magnetic body closer to the magnetic element and the end portion of the second magnetic body farther from the magnetic element. Therefore, the end of the second soft magnetic body on the side far from the magnetic element is located farther from the substrate than the end of the first soft magnetic body on the side close to the magnetic element. The magnetic body preferentially converges the magnetic flux having the second perpendicular magnetic field component over the first soft magnetic body. As a result, the magnetic flux having the second vertical magnetic field component converged on the second soft magnetic body increases, and the second horizontal magnetic field component converted from the second vertical magnetic field component also increases, resulting in a large horizontal magnetic field component. Can be obtained.

  The first soft magnetic body and the second soft magnetic body are preferably made of a soft magnetic material containing at least one of NiFe, CoFe, CoFeSiB, CoZrTi, and CoZrNb.

  With such an aspect, the magnetic flux having the first vertical magnetic field component and the second vertical magnetic field component is efficiently converged, and the change in the first vertical magnetic field component and the second vertical magnetic field component is followed. Thus, the first soft magnetic body and the second soft magnetic body that change the first horizontal magnetic field component and the second horizontal magnetic field component can be formed. Therefore, a large horizontal magnetic field component corresponding to a change in the first vertical magnetic field component and the second vertical magnetic field component can be applied to the magnetic element.

  It is preferable that an end of the second soft magnetic body on the side far from the magnetic element is in contact with a nonmagnetic film containing at least one of Au, Ti, Cr, and Ta.

  With such an aspect, the nonmagnetic film does not interfere with the magnetic flux having the second vertical magnetic field component, so that a magnetic sensor having a configuration that does not reduce the second horizontal magnetic field component can be obtained.

  It is preferable that an outer periphery of the second soft magnetic body excluding a surface in contact with the nonmagnetic film is covered with an insulating film.

  According to this aspect, the second soft magnetic body can be insulated from the magnetic element and the first soft magnetic body. Therefore, a bridge circuit described later can be formed.

  The plurality of magnetic elements include a first set of magnetic element groups and a second set of magnetic element groups, and the first set of magnetic element groups and the second set of magnetic element groups are electrically connected in series, A bridge circuit having a middle point electrode for output extraction is formed between the group magnetic element group and the second group magnetic element group, and one of the two directions substantially orthogonal to each other on the surface of the substrate is formed. The first soft magnetic body is disposed on the left side of the first set of magnetic elements and the second soft magnetic body is disposed on the right side of the first set of magnetic elements when the other is the left-right direction. Preferably, the second soft magnetic body is disposed on the left side of the second set of magnetic elements, and the first soft magnetic body is disposed on the right side of the second set of magnetic elements.

  In such an aspect, the first horizontal magnetic field component and the second horizontal magnetic field component converted from the first vertical magnetic field component and the second vertical magnetic field component by the first soft magnetic body and the second soft magnetic body are obtained. Then, it flows into the first set magnetic element group and the second set magnetic element group from opposite directions. Therefore, the first perpendicular magnetic field component and the second magnetic field component are formed by the method in which the magnetization directions of the pinned magnetic layers of both the element groups are the same, that is, a plurality of the magnetic elements are easily and appropriately formed on the same substrate. With respect to the vertical magnetic field component, the electric resistances of the two element groups can be changed in reverse. Therefore, it is possible to obtain different outputs between the first output terminal and the second output terminal formed of the middle point electrode for taking out the output, and to generate the magnetic flux having the first vertical magnetic field component and the second vertical magnetic field component. The bridge circuit that detects appropriately can be configured.

  A plurality of magnetic elements including a first magnetic element group and a second magnetic element group are stacked with a pinned magnetic layer having a fixed magnetization direction and a nonmagnetic layer stacked on the pinned magnetic layer by an external magnetic field. A magnetization direction of the pinned magnetic layer of the plurality of magnetic elements, and the magnetic elements of the first set of magnetic elements and the magnetic elements of the second set of magnetic elements. The elements are in the same direction, and the magnetic element, the first soft magnetic body, and the second soft magnetic body are formed to extend in the front-rear direction, and the sensitivity axis direction of the free magnetic layer is the left-right direction. The direction is preferred.

  In such a mode, since the magnetization directions of the fixed magnetic layers of all the magnetic elements are the same, the resistance values of all the magnetic elements change similarly with respect to the horizontal magnetic field component from the outside. The external horizontal magnetic field component can be prevented from affecting the output of the bridge circuit.

  Further, the magnetic element, the first soft magnetic body, and the second soft magnetic body are formed to extend in the front-rear direction, so that a magnetic flux having the first vertical magnetic field component and the second vertical magnetic field component is generated. Since it can converge from a wide area, the sensitivity of the magnetic element is improved.

  It is preferable that the magnetic element is shorter in the front-rear direction than the first soft magnetic body and the second soft magnetic body disposed on both the left and right sides thereof.

  In such an aspect, since the magnetic flux having the horizontal magnetic field component from the front-rear direction is shielded, the influence on the output of the bridge circuit due to the magnetic flux having the horizontal magnetic field component from the front-rear direction can be reduced.

  Preferably, each of the first set of magnetic elements and the second set of magnetic elements includes at least one magnetic element. If it is such an aspect, the said 1st group magnetic element group and the said 2nd group magnetic element group can detect the magnetic flux which has a 1st perpendicular magnetic field component and a 2nd perpendicular magnetic field component.

The method of manufacturing a magnetic sensor according to the present invention includes: a magnetic element that exhibits a magnetoresistive effect on the surface side of a substrate; a first soft magnetic body that is spaced apart from the magnetic element and disposed on the surface side; A second soft magnetic body that is spaced apart and disposed on the back surface side of the substrate, and the first soft magnetic body and the second soft magnetic body are in a first direction within the substrate surface. The magnetic element is disposed therebetween, and the first soft magnetic body is disposed on the opposite side of the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the substrate surface. A method for manufacturing a magnetic sensor, comprising:
(A) forming the magnetic element on the surface side of the substrate;
(B) filling the resist holes formed on the surface side of the substrate with a soft magnetic material to form the first soft magnetic body;
(C) forming a deep groove from the surface side of the substrate into the substrate, and forming the second soft magnetic body filling the deep groove with a soft magnetic material;
It is characterized by having.

  According to this aspect, the magnetic sensor in which the back surface side end portion of the first soft magnetic body and the front surface side end portion of the second soft magnetic body are disposed to face each other with the magnetic element interposed therebetween. Can be manufactured.

  Therefore, the magnetic flux converged from the outside at the surface side end of the first soft magnetic body is guided outward from the back side end of the first soft magnetic body, and passes through the magnetic element. A magnetic sensor converged on the surface side end of the second soft magnetic body can be manufactured. As a result, it is possible to manufacture a magnetic sensor in which the first vertical magnetic field component is converted into the first horizontal magnetic field component having a large horizontal component at the position of the magnetic element.

  Further, the magnetic flux converged from the outside at the back surface side end portion of the second soft magnetic body is guided outward from the surface side end portion of the second soft magnetic body, passes through the magnetic element, It is possible to manufacture a magnetic sensor that converges on the back side end of the first soft magnetic body. As a result, it is possible to manufacture a magnetic sensor in which the second vertical magnetic field component is converted into a second horizontal magnetic field component having a large horizontal component at the position of the magnetic element.

  In this way, it is possible to manufacture a magnetic sensor with a high efficiency in conversion from the first vertical magnetic field component and the second vertical magnetic field component to the horizontal magnetic field component.

Therefore, according to this invention, the manufacturing method of the magnetic sensor which detects a magnetic field with high sensitivity can be provided by using the soft magnetic body arrange | positioned facing.

  ADVANTAGE OF THE INVENTION According to this invention, the magnetic sensor which detects a magnetic field with high sensitivity using the soft magnetic body arrange | positioned facing can be provided.

1 is a schematic plan view of a Z-axis magnetic sensor according to a first embodiment. FIG. 2 is a schematic plan view in which a first soft magnetic body and a second soft magnetic body are removed from the Z-axis magnetic sensor shown in FIG. 1. FIG. 2 is a partially enlarged schematic cross-sectional view of a Z-axis magnetic sensor cut along the line AA shown in FIG. 1 and viewed from the arrow direction. 1 is a circuit schematic diagram of a Z-axis magnetic sensor in a first embodiment. It is a partial section schematic diagram of the magnetic element in a 1st embodiment. It is a plane conceptual diagram of a magnetic sensor provided with a Z-axis magnetic sensor, an X-axis magnetic sensor, and a Y-axis magnetic sensor. It is a longitudinal cross-sectional conceptual diagram which shows the magnetic field distribution around the 1st soft-magnetic body of 1st Embodiment, a magnetic element, and a 2nd soft-magnetic body. It is a schematic diagram of the magnetic field intensity produced between a 1st soft magnetic body and a 2nd soft magnetic body. It is explanatory drawing of the manufacturing method of the Z-axis magnetic sensor in 1st Embodiment. 2 is a schematic plan view of a Z-axis magnetic sensor which is a modification of FIG. 1. It is the partial expanded sectional schematic of the Z-axis magnetic sensor which is a modification of 1st Embodiment. 6 is a schematic plan view of a Z-axis magnetic sensor according to a second embodiment. It is a circuit schematic diagram of a Z-axis magnetic sensor in a 2nd embodiment. It is a partial expansion plane schematic diagram of the Z-axis magnetic sensor in a 2nd embodiment.

<First Embodiment>
FIG. 1 is a schematic plan view of a Z-axis magnetic sensor in the present embodiment, and FIG. 2 is a schematic plan view in which the first soft magnetic body and the second soft magnetic body are removed from the Z-axis magnetic sensor shown in FIG. 3 is a partially enlarged schematic cross-sectional view of the Z-axis magnetic sensor taken along the line AA shown in FIG. 1 and viewed from the arrow direction. FIG. 4 is a schematic circuit diagram of the Z-axis magnetic sensor in the present embodiment. FIG. 5 is a schematic partial sectional view of a magnetic element in the present embodiment, FIG. 6 is a conceptual plan view of a magnetic sensor including a Z-axis magnetic sensor, an X-axis magnetic sensor, and a Y-axis magnetic sensor, and FIG. 7 is a first view of the first embodiment. FIG. 8 is a schematic cross-sectional view showing the magnetic field distribution around the soft magnetic body, the magnetic element, and the second soft magnetic body, and FIG. 8 is a schematic diagram of the magnetic field strength generated between the first soft magnetic body and the second soft magnetic body. FIG. 9 is an explanatory diagram of a method for manufacturing the Z-axis magnetic sensor in the present embodiment. Each drawing shows the dimensions appropriately different from the actual dimensions for easy viewing.

  The X-axis direction and the Y-axis direction shown in each figure indicate two directions orthogonal to the back surface of the substrate 2, and the Z-axis direction indicates a direction orthogonal to the back surface of the substrate 2. The Y1-Y2 direction is the “front-rear direction”, the Y1 direction is the front, and the Y2 direction is the rear. The X1-X2 direction is the “left-right direction”, the X1 direction is the right direction, and the X2 direction is the left direction. The Z1-Z2 direction is the “vertical direction”, the Z1 direction is the upward direction, and the Z2 direction is the downward direction.

  The Z-axis magnetic sensor 1 including the magnetic element S in the present embodiment constitutes a geomagnetic sensor that is mounted on a mobile device such as a mobile phone.

  As shown in FIG. 6, the geomagnetic sensor includes three X-axis magnetic sensors 50, Y-axis magnetic sensor 70, and Z-axis magnetic sensor 1 whose sensitivity axis directions are orthogonal to each other, and the three magnetic sensors are orthogonal to each other in magnetic field. A magnetic field component in the X-axis direction, a magnetic field component in the Y-axis direction, and a magnetic field component in the Z-axis direction are detected. However, as will be described later, the magnetic field component in the Z-axis direction is converted in the horizontal direction by the first soft magnetic body 4 and the second soft magnetic body 5.

  As shown in FIGS. 1 and 3, the Z-axis magnetic sensor 1 includes a magnetic element S formed on a substrate 2, a first soft magnetic body 4, and a second soft magnetic body 5. ing. A magnetic element S is disposed between the first soft magnetic body 4 and the second soft magnetic body 5, and the magnetic element S, the first soft magnetic body 4, and the second soft magnetic body 5 are arranged in the left-right direction. They are arranged at intervals. Further, the magnetic element S, the lower end portion 4b1 of the first soft magnetic body 4, and the upper end portion 5a1 of the second soft magnetic body 5 are arranged so as to overlap in the vertical direction.

  As shown in FIG. 3, a plurality of magnetic elements S are formed on a substrate 2 made of silicon or the like via a first insulating film 12, a nonmagnetic film 13, a second insulating film 14, and a third insulating film 15. Yes.

  As shown in FIG. 5, the magnetic element S is formed by laminating, for example, an antiferromagnetic layer 33, a pinned magnetic layer 34, a nonmagnetic layer 35, and a free magnetic layer 36 in this order from the bottom. The surface is covered with a protective layer 37. The magnetic element S is formed by, for example, a sputtering method (Sputtering Method).

  The antiferromagnetic layer 33 is made of an antiferromagnetic material such as an IrMn alloy (iridium-manganese alloy). The fixed magnetic layer 34 is formed of a soft magnetic material such as a CoFe alloy (cobalt-iron alloy). The nonmagnetic layer 35 is made of Cu (copper) or the like. The free magnetic layer 36 is made of a soft magnetic material such as a NiFe alloy (nickel-iron alloy). The protective layer 37 is made of Ta (tantalum) or the like. The stacked configuration of the magnetic element S shown in FIG. 5 is an example, and other stacked configurations are possible.

  In the magnetic element S, the magnetization direction (P direction) of the pinned magnetic layer 34 is fixed by exchange coupling between the antiferromagnetic layer 33 and the pinned magnetic layer 34. In the present embodiment, as will be described later, the magnetic element S has a shape extending in the front-rear direction (Y1-Y2). As shown in FIG. 5, the fixed magnetization direction (P direction) of the fixed magnetic layer 34 is, for example, right It faces in the direction (X1). On the other hand, the magnetization direction of the free magnetic layer 36 varies depending on the external magnetic field. Further, the free magnetic layer 36 is moved in the front-rear direction (Y1-Y2) in a no-magnetic-field component state (a state in which no external magnetic field is applied) by a bias magnetic field component in the front-rear direction (Y1-Y2) by a permanent magnet (not shown). Is directed.

  When an external magnetic field acts in the same direction as the fixed magnetization direction (P direction) of the fixed magnetic layer 34 and the magnetization direction of the free magnetic layer 36 fluctuates in the external magnetic field direction, the fixed magnetization direction of the fixed magnetic layer 34 and the free magnetic layer 36 are changed. As the magnetization direction approaches parallel, the electrical resistance value decreases.

  On the other hand, when an external magnetic field acts in a direction opposite to the fixed magnetization direction (P direction) of the fixed magnetic layer 34 and the magnetization direction of the free magnetic layer 36 changes to the external magnetic field direction, the fixed magnetization direction (P direction) of the fixed magnetic layer 34. ) And the magnetization direction of the free magnetic layer 36 approach antiparallel, and the electrical resistance value increases.

  In the present embodiment, the magnetic element S is a giant magnetoresistive effect (GMR) element as described above, but a tunnel effect (TMR) element or a Hall element is also possible. It is.

  As shown in FIGS. 1 and 2, a plurality of magnetic elements S <b> 1 to S <b> 18 are formed on the substrate 2. Each of these magnetic elements S1 to S18 has a shape extending longer in the front-rear direction (Y1-Y2) than the width dimension in the left-right direction (X1-X2). Each of the magnetic elements S1 to S18 has a different length in the front-rear direction (Y1-Y2). This is connected in series between the input terminal (Vdd) and the second output terminal (V2) shown in FIG. The total length of the total element length of the plurality of magnetic elements S1, S2, S3 and the plurality of magnetic elements S9, S10, S11, S12 connected in series between the input terminal (Vdd) and the first output terminal (V1). , S13 and the total length of the element length, and the element length of the plurality of magnetic elements S4, S5, S6, S7, and S8 connected in series between the ground terminal (GND) and the second output terminal (V2) And the total length of the element length of the plurality of magnetic elements S14, S15, S16, S17, and S18 connected in series between the ground terminal (GND) and the first output terminal (V1) are the same. This is because.

  As shown in FIG. 2, the magnetic elements S are electrically connected by a connection portion 6 made of a nonmagnetic conductive material. Further, the wiring layer 7 made of a nonmagnetic conductive material is drawn out from the front end portions of the magnetic elements S1 and S9, and an input terminal (Vdd) integrated with or separate from the wiring layer 7 is provided on the right end portion of the wiring layer 7. ) Is formed. Also, the wiring layer 7 made of a nonmagnetic conductive material is drawn out from the end portions of the magnetic elements S13 and S14, and the first output terminal integrated with or separate from the wiring layer 7 is provided on the right end portion of the wiring layer 7. Electrode pads 9 constituting (V1) are formed. Further, the wiring layer 7 made of a nonmagnetic conductive material is drawn out from the end portions of the magnetic elements S8 and S18, and a ground terminal (GND) that is integral with or separate from the wiring layer 7 is provided at the right end portion of the wiring layer 7. The electrode pad 10 which comprises is formed. A wiring layer 7 made of a nonmagnetic conductive material is drawn out from the rear ends of the magnetic elements S3 and S4, and a second output terminal integrated with or separate from the wiring layer 7 is provided at the right end of the wiring layer 7. Electrode pads 11 constituting (V2) are formed.

  The connection portion 6, the wiring layer 7, and the electrode pads 8 to 11 are formed of a nonmagnetic conductive material such as Al, Au, or Cr.

  As shown in FIG. 2, each magnetic element S is arranged to meander through the connection portion 6, so that the input terminal (Vdd) and the second output terminal (V2) are connected to each other. Magnetic fields connected in series between one output terminal (V1), between the ground terminal (GND) and the second output terminal (V2), and between the ground terminal (GND) and the first output terminal (V1). The total length of the element length of the element S can be increased and the electrical resistance can be increased. Thereby, the current value supplied from the input terminal (Vdd) is kept small, and the magnetic sensor of this embodiment is driven with low power.

  As shown in FIG. 1, the plurality of first soft magnetic bodies 4 and the plurality of second soft magnetic bodies 5 are longer along the front-rear direction (Y1-Y2) than the width dimension in the left-right direction (X1-X2). It is formed in an extended shape. The first soft magnetic bodies 4 and the second soft magnetic bodies 5 are alternately arranged in the left-right direction (X1-X2) with a predetermined interval therebetween, and the respective magnets are arranged on the left and right sides of the first soft magnetic body 4. Element S is arranged. For example, the magnetic element S <b> 1 and the magnetic element S <b> 9 are disposed on the left and right sides of the first soft magnetic body 4. All the magnetic elements S <b> 1 to S <b> 18 are disposed between the first soft magnetic body 4 and the second soft magnetic body 5.

  As shown in FIG. 3, the first soft magnetic body 4 is formed by being cut into the third insulating film 15 formed on the substrate 2 and extending upward from the bottom surface 15 b. The second soft magnetic body 5 extends downward from a position above the upper surface 16 a of the fourth insulating film 16, and a part thereof is embedded in the second insulating film 14 formed on the substrate 2. It is formed in contact with the nonmagnetic film 13. Thus, the first soft magnetic body 4 is disposed on the opposite side of the second soft magnetic body 5 with respect to the magnetic element S in the height direction (Z1-Z2).

  Further, as shown in FIG. 9H, the second soft magnetic body 5 is embedded in the second insulating film 14, the third insulating film 15, the fourth insulating film 16, and the final passivation film 19, and the lower surface thereof is covered. The entire outer periphery is covered with an insulating film.

  In the present embodiment, the lower surface 4b of the first soft magnetic body 4 is provided in the third insulating film 15, but the present invention is not limited to this. It is possible to provide the lower surface 4 b in the film of the second insulating film 14 by cutting into the film of the second insulating film 14. However, the lower surface 4 b of the first soft magnetic body 4 needs to be provided above the lower surface 5 b of the second soft magnetic body 5.

  The upper surface 5a of the second soft magnetic body 5 can be freely provided as long as it is below the upper surface 4a of the first soft magnetic body 4.

  As shown in FIG. 3, a gap T9 is provided in the height direction (Z1-Z2) between the upper surface 4a of the first soft magnetic body 4 and the upper surface 5a of the second soft magnetic body 5. Further, a gap T10 is provided between the lower surface 4b of the first soft magnetic body 4 and the lower surface 5b of the second soft magnetic body 5 in the height direction (Z1-Z2). And it is preferable that T9 and T10 are about 3-14 micrometers.

  The first soft magnetic body 4 and the second soft magnetic body 5 are made of a soft magnetic material containing at least one selected from NiFe, CoFe, CoFeSiB, CoZrTi, and CoZrNb. The nonmagnetic film 13 is formed of a nonmagnetic material containing at least one of Au, Ti, Cr, and Ta.

  As shown in FIG. 3, each first soft magnetic body 4 has an upper surface 4 a and a lower surface 4 b parallel to the front and back surfaces of the substrate 2, and side surfaces 4 c and 4 c that are vertical surfaces connecting the upper surface 4 a and the lower surface 4 b. Configured. Each of the second soft magnetic bodies 5 includes an upper surface 5a and a lower surface 5b that are parallel to the front and back surfaces of the substrate 2, and side surfaces 5c and 5c that are vertical surfaces that connect the upper surface 5a and the lower surface 5b. Note that the side surfaces 4c and 4c and the side surfaces 5c and 5c can be inclined surfaces in which the respective width dimensions T1 and T2 gradually increase in the vertical direction instead of the vertical surfaces. Further, the upper surface 4a, the lower surface 4b, the upper surface 5a, and the lower surface 5b may not be parallel to the front and back surfaces of the substrate 2.

  As shown in FIG. 3, each magnetic element S, the first soft magnetic body 4, and the second soft magnetic body 5 are provided with an interval of T5 and T6 in the left-right direction (X1-X2), respectively. T5 and T6 are preferably about 0.1 to 2 μm.

  As shown in FIG. 1, magnetic elements S1, S2, and S3 connected in series between the input terminal (Vdd) and the second output terminal (V2), and between the first output terminal (V1) and the ground terminal (GND). The magnetic elements S14, S15, S16, S17, and S18 connected in series are all arranged near the right side of the upper end 5a1 with respect to each second soft magnetic body 5. Further, the magnetic elements S4, S5, S6, S7, S8 connected in series between the second output terminal (V2) and the ground terminal (GND), and between the input terminal (Vdd) and the first output terminal (V1). The magnetic elements S9, S10, S11 connected in series are all arranged in the vicinity of the left side of the upper end 5a1 with respect to each second soft magnetic body 5.

  However, as shown in FIG. 7, the upper end portion 5a1 or the lower end portion 5b1 is a region of both end portions of the second soft magnetic body 5 included in the vicinity of the upper surface 5a or the lower surface 5b of the second soft magnetic body 5, respectively. . Further, the upper end 4a1 or the lower end 4b1 is a region at both ends of the first soft magnetic body 4 included in the vicinity of the upper surface 4a or the lower surface 4b of the first soft magnetic body 4, respectively.

  As shown in FIG. 7A, the vertical magnetic field component H01 from above converges on the first soft magnetic body 4 and enters the inside of the first soft magnetic body 4 from the upper surface 4a. The vertical magnetic field component H01 passes through the first soft magnetic body 4, flows out from the lower end 4b1 (near the lower surface 4b), is converted into a horizontal magnetic field component H02, and acts on each magnetic element S. The horizontal magnetic field component H02 is converged on the second soft magnetic body 5 facing each other across the magnetic elements S, and enters the second soft magnetic body 5 from the upper end portion 5a1 (near the upper surface 5a). And it emits outward from the lower surface 5b of the second soft magnetic body 5.

  The horizontal magnetic field component H02 acts in parallel or antiparallel to the magnetization direction of each pinned magnetic layer 34 in each magnetic element S disposed on the left and right of the first soft magnetic body 4. As described with reference to FIG. 5, the fixed magnetization direction (P direction) of the fixed magnetic layer 34 of each magnetic element S is the right direction (X1). Therefore, in the magnetic element S (S4 to S8 and S9 to S13 shown in FIG. 1) on which the right horizontal magnetic field component H02 acts from the first soft magnetic body 4, the magnetization direction of the free magnetic layer 36 is the right direction (X1 ), The magnetization directions of the pinned magnetic layer 34 and the free magnetic layer 36 are the same, and the electric resistance value is reduced. On the other hand, in the magnetic element S (S1 to S3, S14 to S18 shown in FIG. 1) on which the left horizontal magnetic field component H02 acts from the first soft magnetic body 4, the magnetization direction of the free magnetic layer 36 is the left direction (X2 ), The magnetization directions of the pinned magnetic layer 34 and the free magnetic layer 36 are antiparallel, and the electric resistance value is increased. Therefore, in the bridge circuit shown in FIG. 4, the electric resistance values of the magnetic elements S1 to S3 and S14 to S18 are large, and the electric resistance values of the magnetic elements S4 to S8 and S9 to S13 are small. For this reason, the potential of the first output terminal (V1) is increased, the potential of the second output terminal (V2) is decreased, and by obtaining a differential output, the vertical magnetic field component H01 can be detected from above. .

As shown in FIG. 7B, the vertical magnetic field component H03 from below is converged on the second soft magnetic body 5 and enters the second soft magnetic body 5 from the lower surface 5b. The vertical magnetic field component H03 passes through the second soft magnetic body 5, flows out from the upper end portion 5a1 (near the upper surface 5a), is converted into a horizontal magnetic field component H04, and acts on each magnetic element S.
The horizontal magnetic field component H04 converges on the first soft magnetic body 4 facing each other across the magnetic elements S, and enters the first soft magnetic body 4 from the lower end portion 4b1 (in the vicinity of the lower surface 4b). And it emits outward from the upper surface 4a of the first soft magnetic body 4.

  The horizontal magnetic field component H04 acts in parallel or antiparallel to the magnetization direction of each pinned magnetic layer 34 in each magnetic element S disposed on the left and right of the first soft magnetic body 4. As described with reference to FIG. 5, the fixed magnetization direction (P direction) of the fixed magnetic layer 34 of each magnetic element S is the right direction (X1). Therefore, in the magnetic element S (S1 to S3, S14 to S18 shown in FIG. 1) on which the right horizontal magnetic field component H04 acts from the second soft magnetic body 5, the magnetization direction of the free magnetic layer 36 is the right direction (X1). ), The magnetization directions of the pinned magnetic layer 34 and the free magnetic layer 36 are the same, and the electric resistance value is reduced. On the other hand, in the magnetic element S (S4 to S8, S9 to S13 shown in FIG. 1) on which the left horizontal magnetic field component H04 acts from the first soft magnetic body 4, the magnetization direction of the free magnetic layer 36 is the left direction (X2 ), The magnetization directions of the pinned magnetic layer 34 and the free magnetic layer 36 are antiparallel, and the electric resistance value is increased. Therefore, in the bridge circuit shown in FIG. 4, the electrical resistance values of the magnetic elements S1 to S3 and S14 to S18 are small, and the electrical resistance values of the magnetic elements S4 to S8 and S9 to S13 are large. For this reason, the potential of the first output terminal (V1) is reduced, the potential of the second output terminal (V2) is increased, and the vertical magnetic field component H03 can be detected from below by obtaining a differential output. .

  In FIG. 7, only the magnetic fields necessary for the explanation in FIG. 7 are shown, and the other magnetic fields are omitted. Actually, the magnetic field component of the vertical magnetic field component H01 is converged on the upper surface 4a of each first soft magnetic body 4 and the side surfaces 4c and 4c of the upper end portion 4a1 in the vicinity of the upper surface 4a. The second soft magnetic body 5 converges to the lower surface 5b and the side surfaces 5c and 5c of the lower end portion 5b1 in the vicinity of the lower surface 5b. Further, since the vertical magnetic field component H01 from above and the vertical magnetic field component H03 from below change the increase / decrease in the midpoint potential in reverse, the difference between them is detected separately.

  FIG. 8 shows a schematic diagram of the magnetic field strength generated between the first soft magnetic body 4 and the second soft magnetic body 5. As shown in FIG. 8, each lower end 4b1 and each upper end 5a1 are arranged horizontally (parallel to the front and back surfaces of the substrate 2). Therefore, when the magnetic flux having the vertical magnetic field component H01 is converted into the magnetic flux having the horizontal magnetic field component H02 from above and flows out from the respective lower end portions 4b1, the magnetic flux having the horizontal magnetic field component H02 is converted into the respective upper end portions 5a1. Try to enter horizontally. As a result, the vertical magnetic field component H01 is converted into a large horizontal magnetic field component H02.

  Further, when the magnetic flux having the vertical magnetic field component H03 is converted into the magnetic flux having the horizontal magnetic field component H04 from the lower side and flows out from the upper end portions 5a1, the magnetic flux having the horizontal magnetic field component H04 is transferred to the lower end portions 4b1. Try to enter horizontally. As a result, the vertical magnetic field component H03 is converted into a large horizontal magnetic field component H04.

  Because of the symmetry between the direction of the magnetic flux and each of the soft magnetic bodies 4 and 5, the flow of the magnetic flux is basically the same even if the direction of the magnetic flux is reversed. Therefore, vertical magnetic field components from above and below are similarly converted into large horizontal magnetic field components.

  Therefore, the vertical magnetic field component H01 and the vertical magnetic field component H03 are converted into a horizontal magnetic field component H02 and a horizontal magnetic field component H04 having a large horizontal magnetic field component, and the fixed magnetic layer 34 of each magnetic element S constituting the Z-axis magnetic sensor 1 is fixed. Since the magnetization direction (P direction) is the horizontal direction, the Z-axis magnetic sensor 1 can detect the vertical magnetic field component H01 and the vertical magnetic field component H03 with high sensitivity.

  As shown in FIG. 8, a strong magnetic field is distributed substantially uniformly between the first soft magnetic body 4 and the second soft magnetic body 5. Therefore, the installation accuracy when installing each magnetic element S between the first soft magnetic body 4 and the second soft magnetic body 5 is not strictly required. However, in consideration of installation accuracy, each magnetic element S is preferably installed in the vicinity of the center between the lower end 4b1 and the upper end 5a1.

  The reason why the vertical magnetic field component H01 and the vertical magnetic field component H03 can be detected in the present embodiment is that each of the first soft magnetic body 4 and the second soft magnetic body 5 is converted into a horizontal magnetic field component H02 and a horizontal magnetic field component H04. is there. In order to improve this conversion efficiency, it demonstrates with reference to FIG.3 and FIG.7, but each width dimension in the left-right direction (X1-X2) of each 1st soft magnetic body 4 and each 2nd soft magnetic body 5 is demonstrated. The aspect ratios (T3 / T1, T4 / T2) of the height dimensions T3, T4 in the height direction (Z1-Z2) with respect to T1, T2 may be increased to about 1.5 to 5 times. desirable.

  Accordingly, the upper surface 4a of the first soft magnetic body 4 and the side surfaces 4c and 4c of the upper end portion 4a1 in the vicinity of the upper surface 4a are appropriately used as main converging surfaces of the vertical magnetic field component H01 from the upper side to the lower side (from the Z1 direction to the Z2 direction). On the other hand, the lower surface 4b and the side surfaces 4c and 4c of the lower end portion 4b1 in the vicinity of the lower surface 4b function as main outflow surfaces through which the magnetic field that has passed through the first soft magnetic body 4 flows out. This can occur in the vicinity of the magnetic element S.

  Further, the lower surface 5b of the second soft magnetic body 5 and the side surfaces 5c and 5c of the lower end 5b1 in the vicinity of the lower surface 5b function appropriately as main converging surfaces of the vertical magnetic field component H03 from the lower side to the upper side (from the Z2 direction to the Z1 direction). On the other hand, the upper surface 5a and the side surfaces 5c and 5c of the upper end portion 5a1 in the vicinity of the upper surface 5a function as main outflow surfaces through which the magnetic field that has passed through the second soft magnetic body 5 flows out. This can occur in the vicinity of the element S.

  The reason why the upper limit of the aspect ratio is set to 5 is that if it is about 5, the conversion efficiency can be made very good, and if it is larger than 5, the low profile of the Z-axis magnetic sensor 1 is hindered. T1 and T2 are about 3 to 10 μm, and T3 and T4 are about 5 to 15 μm.

  In the present embodiment, as shown in FIGS. 1 and 7, the plurality of magnetic elements S are disposed between the lower end 4 b 1 of the first soft magnetic body 4 and the upper end 5 a 1 of the second soft magnetic body 5. . In addition, the fixed magnetization direction (P direction) of the fixed magnetic layer 34 of each magnetic element S is all aligned in the same direction. Thereby, each magnetic element S has a horizontal magnetic field component H05 in the left-right direction (X1-X2) from the outside (see FIG. 7) or a horizontal magnetic field component H06 in the front-back direction (Y1-Y2) from the outside (not shown). ), All the magnetic elements S exhibit the same resistance value, so the output terminals V1 and V2 in the bridge circuit shown in FIG. On the other hand, since the horizontal magnetic field components in the opposite direction act on the magnetic elements S arranged on the left and right of the first soft magnetic body 4 with respect to the external vertical magnetic field components H01 and H03, the first soft magnetic body 4 shows a resistance value different between each magnetic element S arranged on the right side of 4 and each magnetic element S arranged on the left side of the first soft magnetic body 4, and the bridge shown in FIG. 4 using each magnetic element S1 to S18. By constructing a circuit, it is possible to suppress the detection of the external horizontal magnetic field component H05 and the external horizontal magnetic field component H06 and configure the Z-axis magnetic sensor 1 capable of appropriately detecting the vertical magnetic field components H01 and H03. can do.

  Further, as described above, in this embodiment, since the fixed magnetization direction (P direction) of the fixed magnetic layer 34 of all the magnetic elements S can be made the same, all the magnetic elements S are simultaneously formed on the same substrate 2. Therefore, the manufacture of the Z-axis magnetic sensor 1 can be facilitated.

  As shown in FIGS. 1 and 2, the magnetic elements S <b> 1 to S <b> 18, the first soft magnetic body 4, and the second soft magnetic body 5 extend in parallel in the front-rear direction (Y1-Y2). The magnetic elements S1 to S18 are formed shorter than the first soft magnetic body 4 and the second soft magnetic body 5. Therefore, when the magnetic elements S are arranged on the left and right sides of the first soft magnetic body 4, they can be arranged so as to face each other in the left-right direction (X1-X2) like the magnetic elements S1 and S9. The magnetic elements S10, S2, and S5 can be arranged so as to be shifted in the front-rear direction (Y1-Y2).

  As shown in FIGS. 1 and 3, the width dimensions T1 and T2 in the left-right direction (X1-X2) of the first soft magnetic body 4 and the second soft magnetic body 5 can be formed short. The magnetic element S can be disposed in the vicinity of the lower end portion 4b1 and in the vicinity of the upper end portion 5a1 of the second soft magnetic body 5. Therefore, since the magnetic element S, the first soft magnetic body 4 and the second soft magnetic body 5 can be arranged in a compact manner, the Z-axis magnetic sensor 1 can be reduced in size. Further, the Z-axis magnetic sensor 1 can be formed in the same size as the X-axis magnetic sensor and the Y-axis magnetic sensor in plan view.

  FIG. 10 is a schematic plan view of a Z-axis magnetic sensor which is a modification of FIG. In this modification, each magnetic element S is arranged on both the left and right sides of the second soft magnetic body 5. Other than this, the second embodiment is the same as the first embodiment.

  Therefore, the horizontal magnetic field components H02 and H04 act on the magnetic elements S in the opposite direction to the first embodiment with respect to the vertical magnetic field components H01 and H03. Therefore, each magnetic element S detects the vertical magnetic field components H01 and H03 by changing the resistance value of the first and second embodiments in reverse to obtain the differential output of the bridge circuit shown in FIG. be able to.

  The manufacturing method of this embodiment is demonstrated using FIG. First, as shown in FIG. 9A, a first insulating film 12, a nonmagnetic film 13, a second insulating film 14, and a third insulating film 15 are stacked on the surface of the substrate 2.

  The substrate 2 is, for example, a silicon substrate, and the first insulating film 12 is, for example, a thermal oxide film formed by thermally oxidizing the silicon substrate. The film thickness of the first insulating film 12 is about 0.05 to 0.3 μm. The nonmagnetic film 13 is made of, for example, a nonmagnetic material containing at least one of Au, Ti, Cr, and Ta. The nonmagnetic film 13 is formed on the entire surface of the substrate 2 and functions as a plating seed layer of the second soft magnetic body 5. Is about 0.05 to 0.3 μm. The second insulating film 14 is, for example, a silicon nitrite film or a silicon oxide film, and the film thickness is about 4 to 14 μm. The third insulating film 15 is, for example, an alumina film, and the film thickness is about 0.05 to 0.5 μm. The nonmagnetic film 13, the second insulating film 14, and the third insulating film 15 can be formed using a thin film forming technique such as a sputtering method or a CVD method (Chemical Vapor Deposition Method).

  As shown in FIG. 9B, on the third insulating film 15, for example, as shown in FIG. 5, the antiferromagnetic layer 33, the pinned magnetic layer 34, the nonmagnetic layer 35, the free magnetic layer 36, and By laminating and forming the protective layers 37 in this order, a multilayer multilayer film constituting the magnetic element S is formed. Next, patterning formation of the magnetic element S (for example, the pattern shown in FIG. 2) is performed by using a photolithography processing technique including a resist pattern forming technique and an etching technique. Next, for example, the connection portion 6 and the wiring layer 7 shown in FIG. 2 are formed by repeating the thin film formation technique and the photolithography process technique. The connection portion 6 and the wiring layer 7 are made of a conductive material such as Al, Au, or Cr.

  As shown in FIG. 9C, a fourth insulating film 16 is formed, and contact holes for gold plating (not shown) are formed in the electrode pads 8 to 11 shown in FIG. A gold seed layer (not shown) is deposited. The 4th insulating film 16 is an alumina film, for example, and the film thickness is about 0.1-0.5 micrometer. The film thickness of the gold seed layer is about 0.01 to 0.1 μm. The fourth insulating film 16 and the gold seed layer can be formed by sputtering or the like.

  At this time, the X-axis magnetic sensor 50, the Y-axis magnetic sensor 70, and the Z-axis magnetic sensor 1 constituting the magnetic sensor are simultaneously formed on the substrate 2. FIG. 9 shows only one magnetic element S necessary for the description and its periphery, but actually, a plurality of magnetic elements S, a plurality of wiring layers 7, a plurality of electrode pads 8 to 11 and the like. Although these are omitted, they are not shown.

  Next, a manufacturing process for forming the first soft magnetic body 4 and the second soft magnetic body 5 included in the Z-axis magnetic sensor 1 will be described with reference to FIGS. 9D to 9G.

  As shown in FIG. 9D, a first resist film 17 is applied, and the first resist film 17 is patterned by exposure and development. Then, using the first resist film 17 as a mask, the fourth insulating film 16, the third insulating film 15, and the second insulating film 14 are etched by deep RIE (Deep Reactive Ion Etching) or the like to form the nonmagnetic film 13. A deep groove reaching is formed.

  As shown in FIG. 9E, a film for forming the second soft magnetic body 5 is formed to a thickness of about 5 to 15 μm by plating or the like using the nonmagnetic film 13 as a plating seed layer. Next, the second soft magnetic body 5 is formed by removing the unnecessary film portion formed by plating or the like by removing the first resist film 17. The second soft magnetic body 5 is made of a soft magnetic material containing at least one of NiFe, CoFe, CoFeSiB, CoZrTi, and CoZrNb.

  As shown in FIG. 9F, a second resist film 18 is applied, and a hole pattern is formed in the second resist film 18 where the first soft magnetic body 4 is to be formed by exposure and development. Then, the fourth insulating film 16 in the hole pattern is removed, and the middle of the third insulating film 15 is removed. This removal can be performed by RIE, ion milling (Ion Milling) method, or the like. Although not shown, a seed layer of a film made of the same material as the first soft magnetic body 4 or a nonmagnetic material containing at least one of Au, Ti, Cr, and Ta is formed to a thickness of about 0.01 to 0.1 μm. The film is formed by sputtering or the like. Next, a film for forming the first soft magnetic body 4 is formed to a thickness of about 5 to 15 μm by plating or the like. Next, by removing the second resist film 18 and removing unnecessary film portions formed by plating or the like, the first soft magnetic body 4 is formed. The first soft magnetic body 4 is made of a soft magnetic material containing at least one of NiFe, CoFe, CoFeSiB, CoZrTi, and CoZrNb.

  As a result, as shown in FIG. 9G, the Z-axis magnetic sensor 1 in which the first soft magnetic body 4 and the second soft magnetic body 5 are arranged with the magnetic element S interposed therebetween is formed. Separately, a shield film that shields the leakage magnetic field of the X-axis magnetic sensor 50 and the Y-axis magnetic sensor 70 is formed, but this is not shown.

  From the next step, the manufacturing process proceeds simultaneously for the X-axis magnetic sensor 50, the Y-axis magnetic sensor 70, and the Z-axis magnetic sensor 1. Although not shown, a resist film is applied, contact holes for gold plating are formed in the electrode pads 8 to 11 shown in FIG. 2 by a resist pattern forming technique, and gold plating is performed. Then, after removing the resist film, the gold seed layer formed in FIG. 9C is removed by etching using the gold plating pattern formed on the electrode pads 8 to 11 as a mask.

  As shown in FIG. 9H, a final passivation film 19 is formed, and pad holes for wire bonding are formed in the electrode pads 8 to 11 shown in FIG. 2 using a photolithography technique. The final passivation film 19 is a silicon nitrite film formed by, for example, a CVD method and has a thickness of about 0.3 to 5 μm.

  On the substrate 2, a plurality of magnetic sensors including the X-axis magnetic sensor 50, the Y-axis magnetic sensor 70, and the Z-axis magnetic sensor 1 are formed. Therefore, although not shown, a plurality of magnetic sensor chips can be manufactured by cutting the substrate 2.

  As described above, in the present embodiment, the second soft magnetic body 5 and the first soft magnetic body 4 are formed after the magnetic elements S that are thin multilayered films are formed. Thus, forming each magnetic element S in the initial stage of the manufacturing process can prevent surface roughness, which is minute unevenness growing on the surface of the substrate every time the manufacturing process is performed, so that each magnetic element The film thickness accuracy of S can be improved. As a result, a magnetic sensor can be manufactured with a small yield and a high yield. In addition, the detection accuracy is improved and the detection sensitivity (S / N ratio) is improved by reducing the characteristic variation of the magnetic sensor.

  When the magnetic element S is formed after the first soft magnetic body 4 or the second soft magnetic body 5 is formed, the flatness of the substrate surface is formed by forming the first soft magnetic body 4 or the second soft magnetic body 5. Therefore, in order to form each magnetic element S with high film thickness accuracy, it is necessary to cover the substrate surface with a thick insulating film and planarize it by CMP (Chemical Mechanical Polishing) or the like.

  For this reason, it is necessary to introduce an expensive CMP apparatus and the like as the number of steps increases, and the manufacturing cost becomes a problem. Therefore, in the present embodiment, by forming each magnetic element S before the first soft magnetic body 4 and the second soft magnetic body 5 are formed, the manufacturing cost can be kept low.

  As shown in FIG. 9G, the lower surface 4b of the first soft magnetic body 4 is provided in the third insulating film 15, but is not limited thereto. Since the second insulating film 14 is formed of an insulating film, it is possible to dig deeply into the second insulating film 14 and provide the lower surface 4 b in the second insulating film 14. Thus, according to the present embodiment, the degree of freedom of overlapping between the first soft magnetic body 4 and each magnetic element S can be increased.

  Also, in the second soft magnetic body 5, the overlap between the second soft magnetic body 5 and each magnetic element S can be freely changed by changing the film thickness.

  Therefore, according to the present embodiment, the degree of freedom in designing the overlapping in the height direction (Z1-Z2) between the first soft magnetic body 4 and the second soft magnetic body 5 and each magnetic element S is large. It is easy to design so that the large horizontal magnetic field components H02 and H04 act. Therefore, according to the present embodiment, the detection sensitivity (S / N ratio) of the Z-axis magnetic sensor 1 can be improved.

  In this embodiment, the substrate 2 is made of silicon or the like, but is not limited to this. The substrate 2 can be an insulating substrate such as a glass substrate. At this time, the first insulating film 12, the second insulating film 14, and the third insulating film 15 may not be formed as in the modification shown in FIG.

  In the present embodiment, the nonmagnetic film 13 is formed, but the present invention is not limited to this. Since the second soft magnetic body 5 can be plated by using the same material as the second soft magnetic body 5 as a seed layer, the nonmagnetic film 13 may not be formed as in the modification shown in FIG.

<Second Embodiment>
FIG. 12 is a schematic plan view of the Z-axis magnetic sensor according to the second embodiment. FIG. 13 is a schematic circuit diagram of the Z-axis magnetic sensor according to the second embodiment. FIG. 14 is a partially enlarged schematic plan view of the Z-axis magnetic sensor according to the second embodiment.

  As shown in FIGS. 12, 13, and 14, the Z-axis magnetic sensor is configured by forming a bridge circuit with four resistance units 101 to 104. FIG. 14A shows a partially enlarged schematic plan view of the first resistor portion 101 and the fourth resistor portion 104, and FIG. 14B shows a partially enlarged schematic plan view of the second resistor portion 102 and the third resistor portion 103. As shown in FIG. 14, the four resistance portions 101 to 104 are formed to include a magnetic element S, a first soft magnetic body 4, and a second soft magnetic body 5.

  As shown in FIG. 14A, the first resistance part 101 and the fourth resistance part 104 have a first soft magnetic body 4 on the left side of each magnetic element S and a second soft magnetic body 5 on each magnetic element S. Located on the right side. Therefore, the first resistance unit 101 and the fourth resistance unit 104 are configured by a first set of magnetic elements.

  As shown in FIG. 14B, the second resistance unit 102 and the third resistance unit 103 include a first soft magnetic body 4 on the right side of each magnetic element S and a second soft magnetic body 5 on each magnetic element S. Located on the left side. Therefore, the 2nd resistance part 102 and the 3rd resistance part 103 are comprised from the 2nd set of magnetic elements.

  The second embodiment is the same as the first embodiment except for the above arrangement, the number of first soft magnetic bodies 4, the second soft magnetic bodies 5, and the number of magnetic elements S and the dimensions in the front-rear direction (Y1-Y2). The same.

  The fixed magnetization direction (P direction) of the fixed magnetic layer 34 of each magnetic element S is the right direction (X1) as in the first embodiment. Further, in the first resistor portion 101 and the fourth resistor portion 104, and the second resistor portion 102 and the third resistor portion 103, horizontal magnetic field formation in the opposite direction acts on the vertical magnetic field component. Therefore, in the first resistance unit 101 and the fourth resistance unit 104, and the second resistance unit 102 and the third resistance unit 103, the increase and decrease of the resistance values are changed inversely with respect to the vertical magnetic field component. Therefore, the vertical magnetic field components H01 and H03 can be detected by obtaining the differential output of the bridge circuit shown in FIG.

  In the second embodiment, the lengths of all the magnetic elements S in the front-rear direction (Y1-Y2) are made the same. However, the lengths of the magnetic elements S are made different as in the first embodiment. It is also possible to have the same overall length.

  In this way, a bridge circuit composed of the first set of magnetic elements and the second set of magnetic elements can be formed with the configuration shown in FIGS. 12, 13, and 14.

DESCRIPTION OF SYMBOLS 1 Z-axis magnetic sensor 2 Board | substrate 4 1st soft magnetic body 5 2nd soft magnetic body 6 Connection part 7 Wiring layer 8-11 Electrode pad 12 1st insulating film 13 Nonmagnetic film 14 2nd insulating film 15 3rd insulating film 16 Fourth insulating film 17 First resist film 18 Second resist film 19 Final passivation film 33 Antiferromagnetic layer 34 Fixed magnetic layer 35 Nonmagnetic layer 36 Free magnetic layer 37 Protective layer 50 X-axis magnetic sensor 70 Y-axis magnetic sensor

Claims (13)

A magnetic element for detecting magnetic flux, a first soft magnetic body, and a second soft magnetic body,
Regarding the first direction, the magnetic element is disposed between the first soft magnetic body and the second soft magnetic body,
The magnetism is characterized in that the first soft magnetic body is disposed on the opposite side of the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the first direction. Sensor. A magnetic element that exhibits a magnetoresistive effect on the front surface side of the substrate, a first soft magnetic material that is spaced from the magnetic element and disposed on the front surface side, and is spaced from the magnetic element and disposed on the back surface side of the substrate A second soft magnetic body,
The magnetic element is disposed between the first soft magnetic body and the second soft magnetic body in a first direction in the substrate plane,
The magnetic sensor, wherein the first soft magnetic body is disposed on the opposite side of the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the substrate surface.   The end portion on the back surface side of the first soft magnetic body, the end portion on the front surface side of the second soft magnetic body, and the magnetic element are arranged at positions overlapping each other in the second direction. The magnetic sensor according to claim 2.   The end of the first soft magnetic body on the side far from the magnetic element is located farther from the substrate than the end of the second soft magnetic body on the side close to the magnetic element. Or the magnetic sensor of Claim 3.   The end of the second soft magnetic body on the side far from the magnetic element is located farther from the substrate than the end of the first soft magnetic body on the side close to the magnetic element. The magnetic sensor according to claim 1.   The first soft magnetic body and the second soft magnetic body are made of a soft magnetic material containing at least one of NiFe, CoFe, CoFeSiB, CoZrTi, and CoZrNb. The magnetic sensor according to any one of the above.   The end of the second soft magnetic body on the side far from the magnetic element is in contact with a nonmagnetic film containing at least one of Au, Ti, Cr, and Ta. The magnetic sensor according to claim 1.   The magnetic sensor according to claim 7, wherein an outer periphery of the second soft magnetic body excluding a surface in contact with the nonmagnetic film is covered with an insulating film. The plurality of magnetic elements include a first set of magnetic element groups and a second set of magnetic element groups, and the first set of magnetic element groups and the second set of magnetic element groups are electrically connected in series, A bridge circuit having a midpoint electrode for output extraction is formed between the group magnetic element group and the second group magnetic element group, and
When one of two substantially orthogonal directions on the surface of the substrate is the front-rear direction and the other is the left-right direction,
The first soft magnetic body is disposed on the left side of the first set of magnetic elements and the second soft magnetic body is disposed on the right side of the first set of magnetic elements;
3. The second soft magnetic body is disposed on the left side of the second set of magnetic elements, and the first soft magnetic body is disposed on the right side of the second set of magnetic elements. The magnetic sensor according to claim 8.   A plurality of magnetic elements including a first magnetic element group and a second magnetic element group are stacked with a pinned magnetic layer having a fixed magnetization direction and a nonmagnetic layer stacked on the pinned magnetic layer by an external magnetic field. A magnetization direction of the pinned magnetic layer of the plurality of magnetic elements, and the magnetic elements of the first set of magnetic elements and the magnetic elements of the second set of magnetic elements. The elements are in the same direction, and the magnetic element, the first soft magnetic body, and the second soft magnetic body are formed to extend in the front-rear direction, and the sensitivity axis direction of the free magnetic layer is the left-right direction. The magnetic sensor according to claim 9, wherein the magnetic sensor is a direction.   11. The magnetic sensor according to claim 9, wherein the magnetic element is shorter in the front-rear direction than the first soft magnetic body and the second soft magnetic body disposed on both right and left sides thereof. .   The magnetic sensor according to any one of claims 9 to 11, wherein each of the first set of magnetic element groups and the second set of magnetic element groups includes at least one or more magnetic elements. . A magnetic element that exhibits a magnetoresistive effect on the front surface side of the substrate, a first soft magnetic material that is spaced from the magnetic element and disposed on the front surface side, and is spaced from the magnetic element and disposed on the back surface side of the substrate A second soft magnetic body, and the magnetic element is disposed between the first soft magnetic body and the second soft magnetic body in a first direction in the plane of the substrate. The method of manufacturing a magnetic sensor, wherein the first soft magnetic body is disposed on the opposite side of the second soft magnetic body with respect to the magnetic element in a second direction substantially perpendicular to the substrate surface. And
(A) forming the magnetic element on the surface side of the substrate;
(B) filling the resist holes formed on the surface side of the substrate with a soft magnetic material to form the first soft magnetic body;
(C) forming a deep groove from the surface side of the substrate into the substrate, and forming the second soft magnetic body filling the deep groove with a soft magnetic material;
A method of manufacturing a magnetic sensor, comprising: