JP2014182096A - Magnetic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monopodial magnetic sensor which suppresses effects of surrounding temperature to a minimum and is capable of detecting a magnetic field in a direction other than a magnetic sensitive axis direction.SOLUTION: First and second magnetic sensitive parts 21 and 22 are arranged so that a median line in a shorter-side direction of magnetic convergence parts 31 and 32 intersect with a portion of the first and second magnetic sensitive parts 21 and 22, and a virtual line segment M connecting both centers of the first and second magnetic sensitive parts 21 and 22 and a virtual line segment N connecting both centers of the first and second magnetic convergence parts 31 and 32 are parallel to each other. According to this configuration, a signal is output in accordance with a magnetic field component of an axis direction which is a perpendicular direction relative to a substrate plane, or a magnetic field component of an axis direction which is parallel to the substrate plane and perpendicular to a magnetic sensitive axis of the magnetic sensitive part, from an output signal difference from the first and second magnetic sensitive parts 21 and 22.

Description

  The present invention relates to a magnetic sensor, and more particularly to a magnetic sensor that includes a magnetoresistive element and can detect a magnetic field in an arbitrary direction without causing an increase in current consumption and minimizing the influence of temperature.

  In general, giant magnetoresistive (GMR) elements that detect the presence or absence of magnetism are widely known. The phenomenon in which the electrical resistivity increases when a magnetic field is applied is called the magnetoresistive effect. Although the rate of change is several percent for general substances, this GMR element reaches several tens percent, so it is widely used for hard disk heads. ing.

FIG. 1 is a perspective view for explaining the operation principle of a conventional GMR element, and FIG. 2 is a partial sectional view of FIG. In the figure, reference numeral 1 is an antiferromagnetic layer, 2 is a pinned layer (fixed layer), 3 is a Cu layer (spacer layer), and 4 is a free layer (free rotation layer). Depending on the magnetization direction of the magnetic material, the electron spin scattering changes and the resistance changes. That is, ΔR = (R _AP −R _P ) R _P (R _AP ; when the upper and lower magnetization directions are antiparallel, R _P ; when the upper and lower magnetization directions are antiparallel).
The direction of the magnetic moment of the fixed layer 2 is fixed by magnetic coupling with the antiferromagnetic layer 1. When the direction of the magnetic moment of the magnetization free rotation layer 4 changes due to the leakage magnetic field, the current flowing through the Cu layer 3 changes and the change in the leakage magnetic field can be read.

  FIG. 3 is a configuration diagram for explaining a laminated structure of a conventional GMR element. In the figure, reference numeral 11 is an insulating film, 12 is a free layer (free rotating layer), 13 is a conductive layer, and 14 is a pinned layer (fixed layer). ), 15 is composed of an antiferromagnetic layer, 16 is composed of an insulating film, the free layer (free rotation layer) 12 is a layer whose direction of magnetization is freely rotated, composed of NiFe or CoFe / NiFe, and the conductive layer 13 is composed of A layer in which current is passed and spin scattering occurs and is made of Cu. A pinned layer (fixed layer) 14 is a layer in which the direction of magnetization is fixed in a certain direction, and is made of CoFe or CoFe / Ru / CoFe, The magnetic layer 15 is a layer for fixing the magnetization direction of the pinned layer 14, and is made of PtMn or IrMn. The layers 11 and 16 are made of Ta, Cr, NiFeCr, and AlO. The pinned layer may use a self-bias structure without using an antiferromagnetic layer.

For example, the one described in Patent Document 1 relates to a magnetic recording system using a GMR element, and a spin valve having a fixed ferromagnetic layer improved so that the magnetostatic coupling of the free ferromagnetic layer is minimized. A magnetoresistive (MR) sensor, FIG. 4 shows a laminated structure having a free ferromagnetic layer and a fixed ferromagnetic layer.
Further, for example, the device described in Patent Document 2 relates to a giant magnetoresistive element that is less affected by the direction of the magnetic field and can detect the magnitude of the magnetic field with high accuracy. It is installed with a bias magnet.

Further, for example, the one described in Patent Document 3 relates to a three-axis magnetic sensor that has high sensitivity with respect to orientation detection, is small, and has excellent mass productivity, and is set to be parallel to the substrate surface and orthogonal to each other. A two-axis magnetic sensor unit that detects geomagnetic components in two-axis (X, Y-axis) directions, and a magnetic field that is arranged on the two-axis magnetic sensor unit and that is perpendicular to the plane that includes the two axes (Z-axis) It has been proposed that a three-axis detection sensor can be realized with a smaller number of elements than before by forming a bridge with magnetoresistive elements having different magnetic sensing axes.
Further, for example, the device described in Patent Document 4 relates to a tunnel magnetoresistive element that is less affected by temperature and can accurately detect the magnitude of a magnetic field. This TMR element is magnetically shielded on a chip. Each of which is responsive to a magnetic field.

Japanese Patent Laid-Open No. 7-169026 JP 2012-112589 A JP 2012-127788 A JP 2001-345498 A

However, although the GMR element provided with the laminated structure which has a free ferromagnetic material layer and a fixed ferromagnetic material layer is disclosed in the patent document 1, a magnetoresistive element like the magnetic sensor of this invention is disclosed. There is no disclosure of an arrangement pattern in which the magnetic converging plate and the magnetic converging plate are combined.
Moreover, since the magnetic sensor of patent document 2 and 3 forms a bridge using a magnetoresistive element, and takes out the midpoint potential as an output signal, it includes the resistance value of the substance which forms a magnetoresistive element in an output. Therefore, the output signal fluctuates sensitively to the external temperature.

The GMR element described in Patent Document 4 is a single-axis sensor having an element that is magnetically shielded on the GMR chip and an element that responds to a magnetic field. Only the magnetic field in the direction of the magnetosensitive axis of the element can be detected.
The present invention has been made in view of such a problem, and the object of the present invention is to reduce the influence of ambient temperature to a minimum and to detect a magnetic field other than the direction of the magnetosensitive axis. It is to provide a sensor.

  The present invention has been made to achieve such an object, and the invention according to claim 1 is a magnetic sensor capable of detecting a magnetic field in an arbitrary axial direction with respect to a substrate plane. One and the other magnetic sensitive parts (21, 22, 41, 42, 61, 62, 81, 82) arranged in parallel to the plane and a magnetic converging part (31, 32) arranged in the vicinity of the magnetic sensitive parts , 50, 71, 72, 91, 92), and when the one and the other magnetic sensitive portions (21, 22, 41, 42, 61, 62, 81, 82) view the magnetic sensor in plan view. Further, the middle line (N2) in the short direction of the magnetic converging part (31, 32, 50, 71, 72, 91, 92) is connected to the one and the other magnetic sensitive parts (21, 22, 41, 42, 61, 62, 81, 82) are arranged so as to intersect with one part, Imaginary line segment (M) connecting the centers of the magnetic sensing parts (21, 22, 41, 42, 61, 62, 81, 82) and the magnetic converging parts (31, 32, 71, 72, 91, 92) is parallel to the imaginary line segment (N) connecting the centers of the two or the center line (N1) in the longitudinal direction of the magnetic converging portion (50) is vertical, and the one and the other magnetic sensitive portions (21, 22, 41, 42, 61, 62, 81, 82), the magnetic field component in the axial direction perpendicular to the substrate plane, or parallel to the substrate plane and A magnetic sensor that outputs a signal corresponding to a magnetic field component in an axial direction perpendicular to a magnetic sensitive axis. (FIGS. 5 to 9; all examples)

The invention according to claim 2 is the invention according to claim 1, wherein the magnetic converging portion (31, 32, 71, 72, 91, 92) The other magnetic sensitive part (21, 22, 41, 42, 61, 62, 81, 82) is arranged at a position where at least a part thereof overlaps in the longitudinal direction.
According to a third aspect of the present invention, in the second aspect of the present invention, when the magnetic sensor is viewed in plan, the overlapping area of the magnetic sensing portion and the magnetic converging portion is equal.
According to a fourth aspect of the present invention, in the first, second, or third aspect of the present invention, a differential circuit is provided in which outputs of the one and the other magnetic sensing units are input.

  According to a fifth aspect of the present invention, in the invention according to any of the first to fourth aspects, the one and the other magnetic sensitive portions are first and second magnetic sensitive portions (21, 22). The magnetic converging portions are first and second magnetic converging portions (31, 32), and the first and second magnetic converging portions are arranged on the opposite surface side with the first and second magnetic sensitive portions. An imaginary line segment (M) that is arranged at a position where at least a part thereof overlaps in the longitudinal direction of the part and connects the centers of the first and second magnetic sensing parts, and the centers of the first and second magnetic convergence parts A virtual line segment (N) connecting the two is parallel. (FIG. 5; Example 1)

  According to a sixth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the output signal of the first magnetic sensitive part (21) is S1, and the second magnetic sensitive part (22 ) Output signal S2, resistance of the first and second magnetic sensing parts (21, 22) is R, magnetic field in the X direction is Bx (magnetic field conversion efficiency a), and magnetic field in the Z direction is Bz (magnetic field conversion efficiency c). ), The difference circuit calculates S1 = R + aBx−cBz S2 = R + aBx + cBz S2−S1 = 2cBz.

  The invention according to claim 7 is the invention according to any one of claims 1 to 4, wherein the one and the other magnetic sensitive portions are the third and fourth magnetic sensitive portions (41, 42). The magnetic converging unit is a single third magnetic converging unit (50) disposed between the third and fourth magnetic sensing units, and the third magnetic converging unit is disposed on both sides. An imaginary line segment (M) that is disposed at a position where at least a part of the third and fourth magnetic sensing parts overlaps in the longitudinal direction and connects the centers of the third and fourth magnetic sensing parts; The center line (N1) in the longitudinal direction of the magnetic converging part 3 is vertical. (FIG. 7; Example 2)

  According to an eighth aspect of the present invention, in the seventh aspect of the invention, the output signal of the third magnetic sensing portion (41) is S3, and the output signal of the fourth magnetic sensing portion (42) is the same. S4, when the resistance of the third and fourth magnetic sensing portions (41, 42) is R, the magnetic field in the X direction is Bx (magnetic field conversion efficiency a), and the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c). The difference circuit calculates S3 = R + aBx + cBz S4 = R + aBx-cBz S3-S4 = 2cBz.

  The invention according to claim 9 is the invention according to any one of claims 1 to 4, wherein the one and the other magnetic sensitive portions are fifth and sixth magnetic sensitive portions (61, 62). The magnetic converging portions are fifth and sixth magnetic converging portions (71, 72), and the fifth and sixth magnetic converging portions are located on the opposite side to the opposing surface side, and the fifth and sixth magnetic converging portions are provided. The magnetically sensitive portion is arranged at a position where at least a part thereof overlaps in the longitudinal direction. (FIG. 8; Example 3)

  According to a tenth aspect of the present invention, in the ninth aspect of the invention, the output signal of the fifth magnetic sensing portion (61) is S5, and the output signal of the sixth magnetic sensing portion (62) is the same. S6, when the resistance of the fifth and sixth magnetic sensing parts (61, 62) is R, the magnetic field in the X direction is Bx (magnetic field conversion efficiency a), and the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c). The difference circuit calculates S5 = R + aBx + cBz S6 = R + aBx-cBz S5-S6 = 2cBz.

  According to an eleventh aspect of the present invention, in the invention according to any one of the first to fourth aspects, the one and the other magnetic sensitive portions are seventh and eighth magnetic sensitive portions (81, 82). The magnetic converging units are sixth to eighth magnetic converging units (91, 92, 93), and the sixth magnetic converging unit (91) and the eighth magnetic converging unit (93) are: The sixth magnetic flux concentrating portion (91) is symmetrical with respect to the longitudinal middle line (N1) of the seventh magnetic converging portion (92), and the sixth magnetic converging portion (91) is the longitudinal direction of the seventh magnetic sensitive portion (81). The seventh magnetic flux concentrator (92) is disposed at a position at least partially overlapping in the longitudinal direction of the eighth magnetic sensing section (82), and Due to the difference between the output signals from the seventh and eighth magnetic sensing parts (81, 82), it is parallel to the substrate plane and the first And characterized by outputting a signal corresponding to the magnetic field component in the vertical axis direction to an eighth sense of magnetic sensitive sections magnetic axis. (FIG. 9; Example 4)

The invention according to claim 12 is the invention according to claim 11, wherein an arrangement pattern composed of the sixth magnetic flux concentrating portion and the seventh magnetic sensitive portion, and the seventh magnetic converging portion; The arrangement pattern composed of the eighth magnetic sensing portion is in a line-symmetric structural relationship with respect to the axis in the short direction of the sixth magnetic converging portion.
According to a thirteenth aspect of the present invention, in the invention of the eleventh or twelfth aspect, the middle line in the short direction of the seventh magnetic converging part is located between the centers of the sixth and eighth magnetic converging parts. It is characterized by being parallel to the imaginary line segment that connects and not overlapping.

Further, the invention according to claim 14 is the invention according to claim 11, 12 or 13, wherein the output signal of the seventh magnetic sensing part is S7, the output signal of the eighth magnetic sensing part is S8, The resistance of the seventh and eighth magnetic sensing parts is R, the magnetic field in the X direction is Bx (magnetic field conversion efficiency a), the magnetic field in the Y direction is By (magnetic field conversion efficiency b), and the magnetic field in the Z direction is Bz (magnetic field conversion efficiency). In the case of c), the difference circuit calculates S7 = R + aBx + bBy-cBz S8 = R + aBx-bBy-cBz S7-S8 = 2bBy.
The invention according to claim 15 is the invention according to any one of claims 1 to 14, characterized in that the virtual line segments do not overlap each other.

  According to the present invention, the magnetic field component in the axial direction perpendicular to the substrate plane or the substrate plane perpendicular to the magnetosensitive axis of the magnetosensitive portion due to the difference between the output signals from the one and other magnetic sensitive portions. Can output a signal corresponding to the magnetic field component in the parallel axial direction, minimizing the influence of ambient temperature, and uniaxial magnetism that can detect magnetic fields other than the magnetic sensitive axis direction A sensor can be realized.

It is a perspective view for demonstrating the principle of operation of the conventional GMR element. It is a fragmentary sectional view of FIG. It is a block diagram for demonstrating the laminated structure of the conventional GMR element. It is a top view for demonstrating the pattern shape of GMR. (A), (b) is a block diagram for demonstrating Example 1 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating the calculation of the difference circuit in the present Example 1. FIG. It is a block diagram for demonstrating Example 2 of the magnetic sensor which concerns on this invention. It is a block diagram for demonstrating Example 3 of the magnetic sensor which concerns on this invention. It is a block diagram for demonstrating Example 4 of the magnetic sensor which concerns on this invention. It is a figure which shows the difference circuit in this invention.

Hereinafter, embodiments of the present invention will be described.
The magnetic sensor of the present invention is a magnetic sensor that can detect a magnetic field in an arbitrary axial direction with respect to a substrate plane. As will be sequentially described in each embodiment, one and the other magnetic sensitive portions 21, 22, 41, 42, 61, 62, 81, and 82 are arranged in parallel to the substrate plane, and are arranged in the vicinity of the magnetic sensitive portion. Magnetic converging parts 31, 32, 50, 71, 72, 91, 92, and one and the other magnetic sensitive parts 21, 22, 41, 42, 61, 62, 81, 82 are planar views of the magnetic sensor. When the center line in the short direction of the magnetic converging parts 31, 32, 50, 71, 72, 91, 92 is one and the other magnetic sensitive parts 21, 22, 41, 42, 61, 62, 81, 82 It is arranged to intersect with a part of.

Further, the imaginary line segment M connecting the centers of the one and the other magnetic sensitive parts 21, 22, 41, 42, 61, 62, 81, 82 and the magnetic converging parts 31, 32, 71, 72, 91, 92 The imaginary line segment N connecting the centers is parallel or the middle line N1 in the longitudinal direction of the magnetic converging part 50 is vertical.
With such a configuration, the magnetic field component in the axial direction perpendicular to the substrate plane, due to the difference in the output signals from the one and the other magnetic sensitive parts 21, 22, 41, 42, 61, 62, 81, 82, Alternatively, a signal corresponding to the magnetic field component in the axial direction parallel to the substrate plane and perpendicular to the magnetic sensitive axis of the magnetic sensitive part can be output.

That is, the present invention realizes a single-axis magnetic sensor that can detect a magnetic field in a direction other than the magnetosensitive axis of the magnetosensitive part by simply canceling the difference between the two sensors and canceling the influence of the element characteristic change due to the temperature characteristic. be able to.
Further, from the viewpoint of improving measurement accuracy, when the magnetic sensor is viewed in plan, it is preferable that the areas where the magnetically sensitive portion and the magnetic converging portion overlap are equal.
Hereinafter, specific embodiments will be described with reference to the drawings.

5A and 5B are configuration diagrams for explaining the first embodiment of the magnetic sensor according to the present invention, FIG. 5A is a top view, and FIG. 5B is FIG. 5A. FIG. In the figure, reference numeral 21 denotes a first magnetic sensing part, 22 denotes a second magnetic sensing part, 31 denotes a first magnetic convergence part, and 32 denotes a second magnetic convergence part.
The magnetic sensor according to the first embodiment is a magnetic sensor that can detect a magnetic field in an arbitrary axial direction with respect to a substrate plane.
The first and second magnetic sensitive portions 21 and 22 are arranged in parallel to the substrate plane. In addition, the first and second magnetic flux concentrators 31 and 32 are disposed at positions where at least part of the first and second magnetic sensitive units 21 and 22 overlaps in the longitudinal direction. That is, the first and second magnetic flux concentrators 31 and 32 are arranged at positions where at least a part thereof overlaps in the longitudinal direction of the first and second magnetic sensitive units 21 and 22 on the facing surface side.

Further, when the magnetic sensor is viewed in plan, the first and second magnetic sensitive parts 21 and 22 and the magnetic converging parts 31 and 32 are arranged so that the overlapping areas are equal.
Further, a virtual line segment M connecting the centers of the first and second magnetic sensing units 21 and 22 and a virtual line segment N connecting the centers of the first and second magnetic convergence units 31 and 32 are parallel to each other. is there.
With such a configuration, a signal corresponding to the magnetic field component in the axial direction perpendicular to the substrate plane can be output based on the difference between the output signals from the first and second magnetic sensing units 21 and 22.
Further, the magnetic sensor of the first embodiment includes a differential circuit (not shown) to which the outputs of the first and second magnetic sensing units 21 and 22 are input.

In the magnetic sensor shown in FIG. 5, the virtual line segments (M, N) are configured not to overlap each other, but the present invention is not limited to this and may overlap. The magnetosensitive part is not particularly limited as long as it is an element having a magnetosensitive axis in a specific direction. For example, a giant magnetoresistive element (GMR), a tunnel magnetoresistive element (TMR), an anisotropic magnetoresistive element ( AMR) or the like is used. Moreover, it is preferable that the width | variety of the transversal direction of a magnetic sensitive part is 0.1-20 microns.
Moreover, it is preferable that a magnetic converging part consists of a soft magnetic material in any one of NiFe, NiFeB, NiFeCo, and CoFe. Moreover, it is preferable that the thickness of a magnetic convergence part is 1-40 microns.

6A and 6B are configuration diagrams for explaining the calculation of the difference circuit in the first embodiment. FIG. 6A is a top view and FIG. 6B is a diagram of FIG. It is sectional drawing. Reference numerals 21a and 22a in the figure indicate magnetosensitive axes. In addition, the same code | symbol is attached | subjected to the component which has the same function as Fig.5 (a), (b).
The output signal of the first magnetic sensing unit 21 is S1, the output signal of the second magnetic sensing unit 22 is S2, the resistance of the first and second magnetic sensing units 21 and 22 is R, and the magnetic field in the X direction is Bx (magnetic field). When the conversion efficiency a) and the magnetic field in the Z direction are set to Bz (magnetic field conversion efficiency c), the difference circuit is
S1 = R + aBx-cBz
S2 = R + aBx + cBz
S2-S1 = 2cBz
Perform the operation. Thereby, the magnetic field component in the axial direction perpendicular to the substrate plane (magnetic field in the Z-axis direction) can be detected.

FIG. 7 is a block diagram for explaining a magnetic sensor according to a second embodiment of the present invention. In the figure, reference numeral 41 denotes a third magnetic sensing part, 42 denotes a fourth magnetic sensing part, and 50 denotes a third magnetic sensor. The convergence part is shown.
The third magnetic converging unit 50 is a single magnetic converging unit arranged between the third and fourth magnetic sensing units 41 and 42, and the third magnetic converging unit 50 includes both side portions thereof. , A virtual line segment M that is arranged at a position where at least part of the third and fourth magnetic sensing portions 41 and 42 overlaps in the longitudinal direction and connects the centers of the third and fourth magnetic sensing portions 41 and 42 to each other. The middle line N1 in the longitudinal direction of the third magnetic flux concentrator 50 is perpendicular.
With such a configuration, a signal corresponding to the magnetic field component in the axial direction perpendicular to the substrate plane can be output based on the difference between the output signals from the third and fourth magnetic sensing units 41 and 42.

The output signal of the third magnetic sensing unit 41 is S3, the output signal of the fourth magnetic sensing unit 42 is S4, the resistance of the third and fourth magnetic sensing units 41 and 42 is R, and the magnetic field in the X direction is Bx (magnetic field). When the conversion efficiency a) and the magnetic field in the Z direction are set to Bz (magnetic field conversion efficiency c), the difference circuit is
S3 = R + aBx + cBz
S4 = R + aBx-cBz
S3-S4 = 2cBz
Perform the operation. Thereby, the magnetic field component in the axial direction perpendicular to the substrate plane (magnetic field in the Z-axis direction) can be detected.

FIG. 8 is a block diagram for explaining a magnetic sensor according to a third embodiment of the present invention. In the figure, reference numeral 61 denotes a fifth magnetic sensing part, 62 denotes a sixth magnetic sensing part, and 71 denotes a fifth magnetic sensor. A converging part 72 is a sixth magnetic converging part.
The first and second magnetic flux concentrators 71 and 72 are arranged at positions where at least a part of the first and second magnetic flux concentrators 71 and 72 overlaps in the longitudinal direction of the fifth and sixth magnetic sensitive portions 61 and 62 on the opposite side to the opposing surface side.
With such a configuration, a signal corresponding to an axial magnetic field component perpendicular to the substrate plane can be output based on the difference between the output signals from the fifth and sixth magnetic sensing units 61 and 62.

The output signal of the fifth magnetic sensing unit 61 is S5, the output signal of the sixth magnetic sensing unit 62 is S6, the resistance of the fifth and sixth magnetic sensing units 61 and 62 is R, and the magnetic field in the X direction is Bx (magnetic field). When the conversion efficiency a) and the magnetic field in the Z direction are set to Bz (magnetic field conversion efficiency c), the difference circuit is
S5 = R + aBx + cBz
S6 = R + aBx-cBz
S5-S6 = 2cBz
Perform the operation. Thereby, the magnetic field of the axial magnetic field component (Z-axis direction) perpendicular to the substrate plane can be detected.

FIG. 9 is a block diagram for explaining a magnetic sensor according to a fourth embodiment of the present invention. In the figure, reference numeral 81 denotes a seventh magnetic sensing part, 82 denotes an eighth magnetic sensing part, and 91 denotes a sixth magnetic sensor. A converging unit, 92 is a seventh magnetic converging unit, and 93 is an eighth magnetic converging unit.
The sixth magnetic converging part 91 and the eighth magnetic converging part 93 are line symmetric with respect to the middle line N <b> 1 in the longitudinal direction of the seventh magnetic converging part 92. In addition, the sixth magnetic flux concentrator 91 is disposed at a position at least partially overlapping in the longitudinal direction of the seventh magnetism sensitive portion 81, and the seventh magnetic flux concentrator 92 is arranged in the eighth magnetism sensitive portion 82. It arrange | positions in the position which at least one part overlaps in a longitudinal direction.

  Further, the arrangement pattern composed of the sixth magnetic converging part 91 and the seventh magnetic sensing part 81 and the arrangement pattern consisting of the seventh magnetic converging part 92 and the eighth magnetic sensing part 82 are the sixth pattern. The magnetic converging part has a line-symmetric structural relationship with respect to the axis in the short direction. In FIG. 9, the arrangement pattern composed of the sixth magnetic converging portion 91 and the seventh magnetic sensing portion 81 is arranged in the short direction of the seventh magnetic sensing portion 81 and the seventh magnetic sensing portion 81. When an imaginary pattern that is line-symmetric with respect to the axis P passing through the center is shifted in the X-axis direction, the virtual pattern is arranged so as to overlap with the arrangement pattern composed of the seventh magnetic converging portion 92 and the eighth magnetic sensing portion 82. Yes.

Further, the middle line N2 in the short direction of the seventh magnetic converging part 92 is configured to be parallel to the virtual line segment N connecting the centers of the sixth and eighth magnetic converging parts 91 and 93 and not to overlap. ing. Further, the line P passing through the centers of the seventh and eighth magnetic sensing portions is configured to be parallel to the virtual line segment N connecting the centers of the sixth and eighth magnetic converging portions 91 and 93 and not to overlap. Has been.
With such a configuration, the magnetosensitive axes of the seventh and eighth magnetosensitive parts 81 and 82 are parallel to the substrate plane due to the difference between the output signals from the seventh and eighth magnetosensitive parts 81 and 82. A signal corresponding to the magnetic field component in the axial direction perpendicular to can be output.

The output signal of the seventh magnetic sensing unit 81 is S7, the output signal of the eighth magnetic sensing unit 82 is S8, the resistance of the seventh and eighth magnetic sensing units 81 and 82 is R, and the magnetic field in the X direction is Bx (magnetic field). When the conversion efficiency a), the magnetic field in the Y direction is By (magnetic field conversion efficiency b), and the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c), the difference circuit is
S7 = R + aBx + bBy-cBz
S8 = R + aBx-bBy-cBz
S7-S8 = 2bBy
Perform the operation. Thereby, the magnetic field component (magnetic field in the Y-axis direction) in the axial direction parallel to the substrate plane and perpendicular to the magnetic sensitive axis of the magnetic sensitive part can be detected.
The difference circuit in each of the embodiments described above may be any circuit that outputs a signal corresponding to the difference between two inputs. When the difference circuit is realized by an analog circuit, for example, a differential amplifier circuit (Vout as shown in FIG. = R2 (V1-V2) / R1) can be used, but the present invention is not limited to this.

  As described above, according to the magnetic sensor of the present invention, the magnetic field component in the axial direction perpendicular to the substrate plane, or the magnetic sensing of the magnetic sensing unit, depending on the difference between the output signals from one and the other magnetic sensing units. A signal corresponding to the magnetic field component in the axial direction perpendicular to the axis and parallel to the substrate plane can be output, so that the influence of the ambient temperature is minimized and the direction other than the magnetic sensitive axis direction A single-axis magnetic sensor capable of detecting a magnetic field can be realized.

1 Antiferromagnetic layer 2 Pinned layer (pinned layer)
3 Cu layer (spacer layer)
4 Free layer (free rotation layer)
11, 16 layers 12 free layers (free rotation layers)
13 Conductive layer 14 Pinned layer (fixed layer)
15 Antiferromagnetic layer 21 1st magnetosensitive part 22 2nd magnetosensitive part 31 1st magnetic converging part 32 2nd magnetic converging part 21a, 22a Magnetosensitive axis 41 3rd magnetosensitive part 42 4th Magnetic sensing unit 50 Third magnetic convergence unit 61 Fifth magnetic sensing unit 62 Sixth magnetic sensing unit 71 Fifth magnetic convergence unit 72 Sixth magnetic convergence unit 81 Seventh magnetic sensing unit 82 Eighth sensing unit Magnetic part 91 6th magnetic converging part 92 7th magnetic converging part 93 8th magnetic converging part

Claims (15)

In a magnetic sensor capable of detecting a magnetic field in an arbitrary axial direction with respect to a substrate plane,
One and the other magnetic sensitive part arranged in parallel to the substrate plane, and a magnetic converging part arranged in the vicinity of the magnetic sensitive part,
The one and the other magnetic sensing parts are arranged so that the middle line in the short direction of the magnetic converging part intersects a part of the one and the other magnetic sensing parts when the magnetic sensor is viewed in plan. And
The imaginary line segment connecting the centers of the one and the other magnetic sensing parts and the imaginary line segment connecting the centers of the magnetic convergence parts are parallel or the longitudinal center line of the magnetic convergence part is vertical,
Depending on the difference between the output signals from the one and the other magnetic sensing units, the magnetic field component in the axial direction perpendicular to the substrate plane, or parallel to the substrate plane and the magnetic sensing axis of the magnetic sensing unit A magnetic sensor that outputs a signal corresponding to a magnetic field component in a vertical axial direction.   2. The magnetism according to claim 1, wherein the magnetic converging part is arranged at a position where at least a part thereof overlaps with a longitudinal direction of the one and the other magnetic sensing parts when the magnetic sensor is viewed in plan. Sensor.   3. The magnetic sensor according to claim 2, wherein when the magnetic sensor is viewed in plan, the overlapping area of the magnetically sensitive portion and the magnetic converging portion is equal.   The magnetic sensor according to claim 1, 2 or 3, further comprising a differential circuit to which outputs of the one and the other magnetic sensing units are input. The one and the other magnetic sensitive parts are first and second magnetic sensitive parts, and the magnetic converging part is a first and second magnetic converging part,
The first and second magnetic flux concentrators are arranged at positions where at least a portion thereof overlaps in the longitudinal direction of the first and second magnetic sensitive parts on the facing surface side;
The virtual line segment that connects the centers of the first and second magnetic sensing portions and the virtual line segment that connects the centers of the first and second magnetic convergence portions are parallel to each other. The magnetic sensor in any one of thru | or 4. The output signal of the first magnetic sensing unit is S1, the output signal of the second magnetic sensing unit is S2, the resistance of the first and second magnetic sensing units is R, and the magnetic field in the X direction is Bx (magnetic field conversion efficiency). a) When the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c), the difference circuit is
S1 = R + aBx-cBz
S2 = R + aBx + cBz
S2-S1 = 2cBz
The magnetic sensor according to claim 5, wherein the calculation is performed.   The one and the other magnetic sensitive parts are third and fourth magnetic sensitive parts, and the magnetic converging part is a single third magnet arranged between the third and fourth magnetic sensitive parts. A converging portion, and the third magnetic converging portion is disposed at a position where at least part of the third magnetic converging portion overlaps in the longitudinal direction of the third and fourth magnetic sensitive portions on both sides, and the third and fourth sensitive portions are arranged. 5. The magnetic sensor according to claim 1, wherein an imaginary line segment connecting the centers of the magnetic parts and a middle line in a longitudinal direction of the third magnetic converging part are perpendicular to each other. The output signal of the third magnetic sensing unit is S3, the output signal of the fourth magnetic sensing unit is S4, the resistance of the third and fourth magnetic sensing units is R, and the magnetic field in the X direction is Bx (magnetic field conversion efficiency). a) When the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c), the difference circuit is
S3 = R + aBx + cBz
S4 = R + aBx-cBz
S3-S4 = 2cBz
The magnetic sensor according to claim 7, wherein the calculation is performed. The one and the other magnetic sensitive parts are fifth and sixth magnetic sensitive parts, and the magnetic converging part is a fifth and sixth magnetic converging part,
The fifth and sixth magnetic flux concentrators are arranged at positions that at least partially overlap in the longitudinal direction of the fifth and sixth magnetic sensitive parts on the side opposite to the opposing surface side. The magnetic sensor according to claim 1. The output signal of the fifth magnetosensitive part is S5, the output signal of the sixth magnetosensitive part is S6, the resistance of the fifth and sixth magnetosensitive parts is R, the magnetic field in the X direction is Bx (magnetic field conversion efficiency) a) When the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c), the difference circuit is
S5 = R + aBx + cBz
S6 = R + aBx-cBz
S5-S6 = 2cBz
The magnetic sensor according to claim 9, wherein the calculation is performed. The one and the other magnetic sensitive parts are seventh and eighth magnetic sensitive parts, and the magnetic converging parts are sixth to eighth magnetic converging parts,
The sixth magnetic converging part and the eighth magnetic converging part are axisymmetric with respect to a longitudinal middle line of the seventh magnetic converging part;
The sixth magnetic flux concentrator is disposed at a position at least partially overlapping with the longitudinal direction of the seventh magnetic sensitive portion, and the seventh magnetic convergent portion is longitudinal with respect to the eighth magnetic sensitive portion. Arranged at least partially overlapping
Due to the difference between the output signals from the seventh and eighth magnetic sensing parts, the magnetic field component in the axial direction is parallel to the substrate plane and perpendicular to the magnetic sensing axes of the seventh and eighth magnetic sensing parts. The magnetic sensor according to any one of claims 1 to 4, wherein a corresponding signal is output.   An arrangement pattern composed of the sixth magnetic converging portion and the seventh magnetic sensing portion and an arrangement pattern composed of the seventh magnetic converging portion and the eighth magnetic sensitive portion are the sixth magnetism. The magnetic sensor according to claim 11, wherein the magnetic sensor has a line-symmetric structural relationship with respect to an axis in a short direction of the converging portion.   13. The center line in the short direction of the seventh magnetic converging part is parallel to and does not overlap with an imaginary line segment connecting the centers of the sixth and eighth magnetic converging parts. The magnetic sensor described in 1. The output signal of the seventh magnetic sensing unit is S7, the output signal of the eighth magnetic sensing unit is S8, the resistance of the seventh and eighth magnetic sensing units is R, the magnetic field in the X direction is Bx (magnetic field conversion efficiency) a) When the magnetic field in the Y direction is By (magnetic field conversion efficiency b) and the magnetic field in the Z direction is Bz (magnetic field conversion efficiency c), the difference circuit is
S7 = R + aBx + bBy-cBz
S8 = R + aBx-bBy-cBz
S7-S8 = 2bBy
The magnetic sensor according to claim 11, wherein the magnetic sensor performs the following calculation.   The magnetic sensor according to claim 1, wherein the virtual line segments do not overlap each other.

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