JP2015001467A - Magnetic sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic sensor capable of minimally suppressing the influence of ambient temperature, freely adjusting sensitivity in each magnetic field direction and detecting a multi-axial magnetic field without causing the increase of a chip size.SOLUTION: A first magneto-sensitive part 11a in a first detection section is covered with a magnetic convergence part 21, and a second magneto-sensitive part 12a is juxtaposed to the first magneto-sensitive part 11a on a substrate plane. Between the first magneto-sensitive part 11a and the second magneto-sensitive part 12a, the first magnetic convergence part 21 and a third magnetic convergence part 23 in a second detection section 2 are arranged so as to be line symmetry to a virtual median line in the longitudinal direction of a second magnetic convergence part 22. A fourth magnetic convergence part 24 is adjacent to the second magneto-sensitive part 12a and is arranged so as to cover a gap between a seventh and eighth magneto-sensitive parts 15a and 16a in a third detection section 3.

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 any 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, 101 is an antiferromagnetic layer, 102 is a pinned layer (fixed layer), 103 is a Cu layer (spacer layer), 104 is a free layer (free rotation layer), 202 is a pinned layer (fixed layer), and 203 is Cu. Reference numerals 204 (spacer layer) and 204 denote free layers (free rotation layers). 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 102 is fixed by magnetic coupling with the antiferromagnetic layer 1. When the direction of the magnetic moment of the magnetization free rotation layer 104 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 301 denotes an insulating film, 302 denotes a free layer (free rotating layer), 303 denotes a conductive layer, and 304 denotes a pinned layer (fixed layer). , 305 denotes an antiferromagnetic layer, and 306 denotes an insulating film.

  A free layer (free rotation layer) 302 is a layer in which the direction of magnetization is freely rotated, and is composed of NiFe or CoFe / NiFe. The conductive layer 303 is a layer in which current flows and spin scattering occurs, and is composed of Cu. The layer (fixed layer) 304 is a layer in which the magnetization direction is fixed in a fixed direction, and is made of CoFe or CoFe / Ru / CoFe. The antiferromagnetic layer 305 is a layer for fixing the magnetization direction of the pinned layer 304. The layers 301 and 306 are made of Ta, Cr, NiFeCr, or AlO. The pinned layer may use a self-bias structure without using an antiferromagnetic layer.

For example, the device described in Patent Document 1 relates to a giant magnetoresistive element that is less affected by the direction of the magnetic field and can accurately detect the magnitude of the magnetic field, and this GMR element is biased with respect to the GMR chip. It is installed with a magnet.
Further, the one described in Patent Document 2 relates to a three-axis magnetic sensor having high sensitivity with respect to azimuth detection, and having a small size and excellent mass productivity. The two-axis is set parallel to the substrate surface and orthogonal to each other. A biaxial magnetic sensor unit that detects a geomagnetic component in the (X, Y axis) direction, and a magnetic member that is disposed on the biaxial magnetic sensor unit and collects a magnetic field perpendicular to the plane including the two axes (Z axis) It is 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.

JP 2012-112589 A JP 2012-127788 A

However, since the magnetic sensors of Patent Documents 1 and 2 described above form a bridge using a magnetoresistive element and take out the midpoint potential as an output signal, the output includes the resistance value of the substance forming the magnetoresistive element. Therefore, there is a problem that the output signal varies sensitively with respect to the external temperature.
In addition, since the X and Y sensors form independent bridges, the chip size increases, and since a common magnetoresistive element is used for the X, Y and Z sensors, sensitivity adjustment in each direction is performed independently. Is difficult.

  The present invention has been made in view of such problems, and the object of the present invention is to minimize the influence of ambient temperature and freely adjust the sensitivity of each magnetic field direction. Thus, an object of the present invention is to provide a magnetic sensor capable of detecting multi-axis magnetic fields without increasing the chip size.

  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. In order to detect the magnetic field in the first axial direction parallel to the plane, the first and second have a magnetosensitive axis in the first axial direction and have different sensitivities to the magnetic field in the first axial direction. The first and second magnetic sensing parts (11a and 11b, 12a and 12b) or the third and fourth magnetic sensing parts (11c and 12c) whose magnetic sensing axes with respect to the magnetic field in the first axial direction are antiparallel. Detectors (1a, 1b, 1c) and (FIGS. 6 to 8; Embodiments 1, 2, 3), a magnetic field in a second axial direction parallel to the substrate plane and perpendicular to the first axial direction In order to detect a magnetic field in the first axial direction, and a magnetic field in the first axial direction. The fifth and sixth magnetosensitive portions (13a, 14a) having the same sensitivity to the first and the first to the second magnetic transducers arranged in the vicinity of the fifth and sixth magnetosensitive portions (13a, 14a) to form a magnetic path In order to detect a magnetic field in a third axial direction perpendicular to the substrate plane, a second detection unit (2) composed of three magnetic focusing units (21 to 23) (FIG. 9; Embodiment 4) , Seventh and eighth magnetic sensing portions (15a, 16a) having a magnetic sensitive axis in the first axial direction and having the same sensitivity to the magnetic field in the first axial direction, and the seventh and eighth A third detection comprising the fourth magnetic converging part (24) or the fourth and fifth magnetic converging parts (24, 25) which are arranged in the vicinity of the magnetic sensitive part (15a, 16a) and form a magnetic path. It has the part (3) and (FIGS. 10 and 11; Embodiments 5 and 6).

  According to a second aspect of the present invention, in the first aspect of the present invention, the first detection unit (1a, 1b) includes the first and second magnetic sensitive units (11a to 11b, 12a to A signal corresponding to the magnetic field in the first axial direction based on the difference between the output signals (S1, S2) of 12b) or the output signals (S3, S4) of the third and fourth magnetic sensing parts (11c, 12c). The second detection unit (2) outputs a magnetic field in the second axial direction based on the difference between the output signals (S5, S6) of the fifth and sixth magnetic sensing units (13a, 14a). The third detection unit (3a, 3b) outputs a corresponding signal, and the third detection unit (3a, 3b) is based on the difference between the outputs (S7, S8) of the seventh and eighth magnetic sensing units (15a, 16a). A signal corresponding to the magnetic field in the axial direction is output.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the first to third magnetic convergence units (21 to 23) in the second detection unit (2) When magnetism is input in the longitudinal direction of the second magnetic converging unit (22), the second magnetic converging unit (22) to the first magnetic converging unit (21) and the second magnetic converging unit ( 22) to the third magnetic flux concentrator (23) so that magnetic paths of magnetic flux components are formed respectively, and when viewed in plan, the first magnetic convergent portion (21) and the second magnetic flux concentrator The distance (MW1) between the middle lines from the first virtual middle line (L21) between the magnetic converging parts (22) to the middle line (L13) in the longitudinal direction of the fifth magnetic sensing part (13a), and the first From the second virtual midline (L23) between the second magnetic convergence portion (22) and the third magnetic convergence portion (23). Longitudinal midline (L14) to the midline between the distance (MW2) is equal to or equal to each other magnetically sensitive portion of (14a). (FIG. 9; Embodiment 4)

According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, the seventh and eighth magnetic sensing portions (15a, 16a) in the third detection portion (3a, 3b). ) Is an imaginary line segment (L56) connecting the centers of the seventh and eighth magnetic sensing parts (15a, 16a) when viewed in plan, the longitudinal direction of the fourth magnetic convergence part (24). It is characterized by being parallel to a virtual line segment (L50) that is perpendicular to the virtual midline (L40) of the first magnetic center line and connects the centers of the fourth and fifth magnetic convergence portions (24, 25). (FIGS. 10 and 11; Embodiments 5 and 6)
The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the first magnetic sensing part (11a) in the first detection part (1a) is viewed in plan. Sometimes, it is covered with the magnetic converging part (20), and the second magnetic sensitive part (12a) is provided side by side with the first magnetic sensitive part (11a) on the substrate plane. . (FIG. 6; Embodiment 1)
The invention according to claim 6 is the invention according to claim 5, wherein the magnetic converging part (20) is any one of the first to fifth magnetic converging parts (21 to 25). It is characterized by.

The invention according to claim 7 is the invention according to any one of claims 1 to 4, wherein the first magnetic sensing part (11b) in the first detection part (1b) and the second The width in the short direction is different from that of the magnetic sensitive part (12b). (FIG. 7; Embodiment 2)
The invention according to claim 8 is the invention according to any one of claims 1 to 4, wherein the magnetic sensing axis of the third magnetic sensing part (11c) in the first detection part (1c) is the same. In the + X axis direction, the magnetosensitive axis of the fourth magnetosensitive part (12c) is in the -X axis direction, and the magnetosensitive axis of each magnetosensitive part is antiparallel. (FIG. 8; Embodiment 3)

The invention according to claim 9 is the invention according to any one of claims 1 to 8, wherein the first and third magnetic converging portions (21, 23) in the second detecting portion (2). Is axisymmetric with respect to a virtual midline (L22) in the longitudinal direction of the second magnetic converging part (22) when viewed in plan, and the first and third magnetic converging parts (21, 21) 23) that the imaginary line segment (L10) connecting the centers (C1, C3) of the second magnetic convergence portion (22) is arranged at a position that intersects with a part other than the center (C2). Features. (FIG. 9; Embodiment 4)
The invention according to claim 10 is the invention according to any one of claims 1 to 9, wherein the seventh and eighth magnetic sensing portions (15a, 16a) in the third detection portion (3a). The fourth magnetic flux concentrator (24) is arranged so as to cover the gap. (FIG. 10; Embodiment 5)

An eleventh aspect of the present invention is the invention according to any one of the first to ninth aspects, wherein the seventh and eighth magnetic sensing portions (15a, 16a) in the third detection portion (3b). The fourth and fifth magnetic flux concentrators (24, 25) are arranged so as to cover the outer side. (FIG. 11; Embodiment 6)
According to a twelfth aspect of the present invention, in the first aspect of the invention, the first magnetic sensing portion (11a) of the first detection portion (1a) covers the magnetic convergence portion (20). The second magnetic sensing part (12a) is provided alongside the first magnetic sensing part (11a) on the substrate plane (FIG. 6; Embodiment 1), and the first magnetic sensing part (11a). ) And the second magnetic sensing part (12a), the first and third magnetic converging parts (21, 23) in the second detecting part (2) are the second magnetic converging parts. An imaginary line that is line symmetric with respect to the virtual center line (L22) in the longitudinal direction of the portion (22) and that connects the centers (C1, C3) of the first and third magnetic convergence portions (21, 23). The minute (L10) is arranged at a position that intersects with a part other than the center (C2) of the second magnetic convergence portion (22) (FIG. 9; Mode 4), the second sensing part (12a) is adjacent to the third sensing part (3) so as to cover the gap between the seventh and eighth sensing parts (15a, 16a). A fourth magnetic convergence portion (24) is arranged (FIG. 10; Embodiment 5). (FIG. 12 = FIG. 6 + FIG. 9 + FIG. 10; Example 1 = Embodiment 1 + Embodiment 4 + Embodiment 5)

According to a thirteenth aspect of the present invention, in the twelfth aspect of the present invention, the width of the seventh and eighth magnetically sensitive portions (15b, 16b) in the short direction is the first to the sixth. It is characterized in that it is wider than the width in the short direction of the magnetic sensitive portions (11a to 14a). (FIG. 13; Example 2)
The invention according to claim 14 is the invention according to claim 12, wherein the first magnetic sensing part (11b) and the second magnetic sensing part (12b) in the first detection part (1b). ) And the width in the short direction is different. (FIG. 14; Example 3)
According to a fifteenth aspect of the present invention, in the twelfth aspect of the present invention, the third detection section (3b) covers the outer sides of the seventh and eighth magnetic sensing sections (15a, 16a). The fourth and fifth magnetic flux concentrators (24, 25) are arranged in the above. (FIG. 15; Example 4)

According to a sixteenth aspect of the present invention, in the invention according to the thirteenth aspect, the width in the short direction of the fifth and sixth magnetically sensitive portions (13b, 14b) in the second detection portion (2). Is narrower than the width in the short direction of the first, second, and fifth to eighth magnetic sensing portions (11a, 11c, to 12a to 12c and 15a, 16a). (FIG. 16; Example 5)
The invention according to claim 17 is the invention according to any one of claims 1 to 16, wherein the first and second or third and fourth magnetic sensing portions (11a, 12a / 11b, 12b / 11c, 12c), the difference between the output signals of the fifth and sixth magnetic sensing parts (13a, 14a / 13b, 14b), and the seventh and eighth magnetic sensing parts (15a, 16a). / 15b, 16b), and a difference between the output signals is provided.

According to an eighteenth aspect of the present invention, in the first aspect of the present invention, the width in the short direction of the first to fourth magnetic sensitive portions (11a, 11c, 12a to 12c) is the fifth width. The width is narrower than the width in the short direction of the eighth to eighth magnetic parts (13a to 16a).
According to a nineteenth aspect of the present invention, in the first aspect of the invention, the width in the short direction of the first and second magnetic sensitive portions (11a, 12a) and the fifth and sixth The width in the short direction of the magnetic sensitive parts (13b, 14b) is different from the width in the short direction of the seventh and eighth magnetic sensitive parts (15b, 16b). (FIG. 16; Example 5)
The invention according to claim 20 is the invention according to any one of claims 1 to 19, wherein the first and second magnetic sensitive portions (11a, 12a) and the third and fourth magnetic sensitive portions. (11c, 12c), fifth and sixth magnetic sensing parts (13a, 13b, 14a, 14b) and seventh and eighth magnetic sensing parts (15a, 15b, 16a, 16b) The electric resistance in the absence of a magnetic field is equal.

  According to the magnetic sensor of the present invention, the influence of the ambient temperature can be minimized, and the sensitivity in each magnetic field direction can be freely adjusted, and a multi-axis magnetic field can be obtained without increasing the chip size. A magnetic sensor capable of detection 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 figure for demonstrating the output principle of a magnetic sensing part. (A), (b) is a figure which shows the differential amplifier circuit as an arithmetic circuit used for the magnetic sensor of this invention. (A), (b) is a block diagram for demonstrating the 1st detection part in Embodiment 1 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating the 1st detection part in Embodiment 2 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating the 1st detection part in Embodiment 3 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating the 2nd detection part in Embodiment 4 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram of the 3rd detection part in Embodiment 5 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram of the 3rd detection part in Embodiment 6 of the magnetic sensor which concerns on this invention. (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 Example 2 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating Example 3 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating Example 4 of the magnetic sensor which concerns on this invention. (A), (b) is a block diagram for demonstrating Example 5 of the magnetic sensor which concerns on this invention.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings.
<Magnetic sensor>
The magnetic sensor of the present invention includes a first detector that detects a magnetic field in a first axial direction parallel to the substrate plane, and a second axis that is parallel to the substrate plane and perpendicular to the first axial direction. It is a magnetic sensor provided with the 2nd detection part which detects the magnetic field of a direction, and the 3rd detection part which detects the magnetic field of the 3rd axial direction perpendicular | vertical with respect to a substrate plane.

  The first detection unit includes a magnetic detection unit having a magnetic detection axis in the first axial direction, and the first detection unit has first and second sensitivity different in sensitivity to a magnetic field in the first axial direction. It consists of a magnetic part or a third and a fourth magnetic sensitive part whose magnetic sensitive axes with respect to the magnetic field in the first axial direction are antiparallel to each other. A signal corresponding to the magnetic field in the first axial direction is output based on the difference between the output signals of the first and second magnetic sensing units or the third and fourth magnetic sensing units.

The second detection unit includes a magnetic sensing unit having a magnetic sensing axis in the first axial direction, and fifth and sixth magnetic sensing units having the same sensitivity to a magnetic field in the first axial direction, The first to third magnetic converging units are configured to output a signal corresponding to the magnetic field in the second axial direction based on the difference between the output signals of the fifth and sixth magnetic sensing units.
The third detection unit includes a magnetosensitive unit having a magnetosensitive axis in the first axial direction, and the seventh and eighth magnetosensitive units having the same sensitivity to the magnetic field in the first axial direction, 4 magnetic converging units or fourth and fifth magnetic converging units, and outputs a signal corresponding to the magnetic field in the third axial direction based on the difference between the outputs of the seventh and eighth magnetic sensing units.

In addition, from the viewpoint of accurately detecting the magnetic field in the second axial direction, the first to third magnetic converging units perform the second magnetic converging when the magnetism is input in the longitudinal direction of the second magnetic converging unit. It is preferable that the magnetic path of the magnetic flux component is respectively formed from the first to the third magnetic converging unit and the second magnetic converging unit to the third magnetic converging unit.
Further, from the viewpoint of accurately detecting the magnetic field in the second axial direction, when the magnetic sensor is viewed in plan, from the first virtual midline between the first magnetic converging unit and the second magnetic converging unit, the fifth The longitudinal direction of the sixth magnetic sensing part from the distance between the middle lines to the longitudinal middle line of the magnetic sensing part and the second virtual middle line between the second magnetic converging part and the third magnetic converging part It is preferable that the distance between the middle lines to the middle line is substantially equal to each other.

  In addition, from the viewpoint of accurately detecting the magnetic field in the third axial direction, the seventh and eighth magnetic sensing units are short in the short direction of the fourth or fifth magnetic converging unit when the magnetic sensor is viewed in plan. Is arranged so that the middle line intersects a part of the seventh and eighth magnetic sensing portions, and a virtual line segment connecting the centers of the seventh and eighth magnetic sensing portions is the fourth magnetic convergence. It is preferable that it is perpendicular to the virtual midline in the longitudinal direction of the part and parallel to the virtual line segment connecting the centers of the fourth and fifth magnetic converging parts.

<Magnetic part>
The output of each magnetic sensing unit outputs a signal based on a resistance R depending on the material constituting the element (not depending on the external magnetic field) and a resistance change ΔR that changes in response to the external magnetic field. For example, when the magnetic sensing unit is driven at a constant voltage (V _CONST ), the resistance R + resistance change rate ΔR can be derived from the output current I _OUT .
I _OUT = V _CONST / (R + ΔR)
∝ (R + ΔR)

  The resistance R depending on the material is generally sensitive to an external temperature. For example, in the case of a GMR element made of Cu, the resistance R is about 0.5% in a temperature range from room temperature to 100 ° C. Can change. In contrast, the resistance change ΔR that changes with respect to the external magnetic field is insensitive to the external temperature. For example, in a GMR element, the resistance is only about 0.01% in a temperature range from room temperature to 100 ° C. under a constant magnetic field. The change amount ΔR does not change.

In the magnetic sensor of the present invention, the first and second magnetic sensitive parts, the third and fourth magnetic sensitive parts, the fifth and sixth magnetic sensitive parts, and the seventh and eighth magnetic sensitive parts, It is preferable that the electric resistance of each set of the magnetosensitive parts in the absence of a magnetic field is equal. The equal electric resistance under no magnetic field means that the resistance R depending on the material constituting the element is equal.
A method for equalizing the electric resistance of each group of the magnetic sensing portions in the absence of a magnetic field is not particularly limited. For example, it can be realized by designing the shape of each magnetic sensing portion to an appropriate value.

For example, when the magnetic sensitive portions have the same thickness T and the magnetic sensitive portions are viewed in plan, the magnetic sensitive portions are rectangular, and the lengths L1 and L2 in the longitudinal direction and the widths in the short direction of the magnetic sensitive portions. If the ratios W1 / L1 and W2 / L2 of W1 and W2 are equal, the resistance R under no magnetic field can be easily equalized.
Specific examples of the magnetosensitive portion in the magnetic sensor of the present invention include GMR (giant magnetoresistance), TMR (tunnel magnetoresistance), AMR (anisotropic magnetoresistance), CMR (supergiant magnetoresistance), and a Hall element. This is not the case. From the viewpoint of temperature characteristics, GMR and TMR are preferable, and GMR is more preferable. The width of the magnetic sensitive part in the sensitivity axis direction is not particularly limited, but is preferably 0.1 to 20 microns.

  FIG. 4 is a diagram for explaining the output principle of the magnetic sensing unit. The resistance R is inversely proportional to the cross-sectional area S (of the current path) of the conduction layer when cut along a plane perpendicular to the current direction I of the conduction path of the magnetic sensing portion, and is equal to the length L of the conduction path in the current direction. Proportional. It is assumed that the magnetosensitive part is virtually divided in the current direction by the width of the minute section ΔL, and the cross-sectional area of the plane perpendicular to the current of each divided element is defined by Sj. Sj represents the cross-sectional area (of the current path) of the conductive layer in the plane perpendicular to the current of the j-th element.

The resistance R at this time is proportional to the amount obtained by adding ΔL / Sj to all the elements. If two elements using the same material are used, the amount obtained by adding ΔL / Sj to all the elements is equal. Resistance values are equal.
For example, when the thickness of each magnetic sensing part is equal and the magnetic sensing part is rectangular when the magnetic sensor is viewed in plan, the length L (current direction) of each magnetic sensing part and the short direction (current) If the ratio of the width W in the direction perpendicular to the direction is equal, the resistance R under no magnetic field can be easily equalized.

In the magnetic sensor of the present invention, the state in which the electric resistance of each magnetic sensing part in the absence of a magnetic field is the same includes a state in which the effect of the present invention is not impaired. May be different from each other by about ± 1%, preferably ± 0.1%, more preferably 0.01%.
Further, the method for making the magnetic sensitive axis directions of the magnetic sensitive parts coincide with each other is not particularly limited, but can be realized by, for example, making the magnetic sensitive parts in the same configuration. When the magnetic sensitive part is GMR, there is a method in which the fixed magnetization directions of the pinned layer are made the same direction. In the magnetic sensor of the present invention, the state in which the magnetic sensitive axis directions of the magnetic sensitive portions coincide with each other includes a state different from the parallel state to the extent that the effects of the present invention are not impaired.

Moreover, it is preferable that the 1st thru | or 3rd detection part is provided with the arithmetic circuit which can output the difference of the output signal of each magnetic sensing part.
5A and 5B are diagrams showing a differential amplifier circuit as an arithmetic circuit used in the magnetic sensor of the present invention. In the figure, reference numerals 11 to 16 denote magnetic sensitive portions.
The arithmetic circuit is not particularly limited as long as it can output a signal based on the difference between the outputs of the magnetic sensing units, and the outputs of the magnetic sensing units as shown in FIG. Examples include a differential amplifier circuit that amplifies and outputs a difference value between two inputs at a predetermined ratio, and a digital IC circuit that converts the output of each magnetic sensing unit into a digital signal and performs a difference operation. is not. Since the magnetic sensor of the present invention calculates the difference between a plurality of sets of magnetic sensing units, the differential amplifier circuit using the multiplexer as shown in FIG. 5B can be operated by one operational amplifier. Therefore, it is preferable from the viewpoint of miniaturization.

  FIGS. 6A, 6B to 11A, 11B are configuration diagrams showing first to third detectors for explaining the first to sixth embodiments of the magnetic sensor according to the present invention. 6 (a) and 6 (b) are configuration diagrams for explaining the first detection unit in the first embodiment of the magnetic sensor according to the present invention, and FIGS. 7 (a) and 7 (b) illustrate the present invention. FIG. 8A and FIG. 8B are configuration diagrams for explaining a first detection unit in the second embodiment of the magnetic sensor according to the invention, and FIGS. 8A and 8B are first detection units in the third embodiment of the magnetic sensor according to the present invention. It is a block diagram for demonstrating. In each figure, (a) is a plan view and (b) is a cross-sectional view.

In the figure, reference numeral 1a denotes a first detection unit in the first embodiment, 1b denotes a first detection unit in the second embodiment, 1c denotes a first detection unit in the third embodiment, 11a and 11b denote first magnetic sensing units, Reference numerals 12a and 12b denote a second magnetic sensing part, 11c a third magnetic sensing part, 12c a fourth magnetic sensing part, 20 a magnetic converging part, 31 a substrate, and 32 an insulating layer.
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. Below, the structure of each detection part is demonstrated sequentially.

<First detection unit>
6 (a) and 6 (b), the first detector 1a according to the first embodiment is sensitive to the first axial direction in order to detect a magnetic field in the first axial direction parallel to the substrate plane. The first and second magnetic sensitive portions 11a and 12a each having a magnetic axis and different in sensitivity to a magnetic field in the first axial direction are provided. The widths in the short direction of the first magnetic sensing part 11a and the second magnetic sensing part 12a are indicated by W1 and W2, respectively, and there is a relationship of W1 = W2.

  Further, the first magnetic sensing unit 11a in the first detection unit 1a is covered with the magnetic converging unit 20 when viewed in plan, and the second magnetic sensing unit 12a is arranged on the plane of the substrate 31. It is attached to the magnetic sensing part 11a. In addition, it is preferable that the magnetic convergence part 20 is either the 1st thru | or 5th magnetic convergence part 21 thru | or 25 mentioned later.

  7 (a) and 7 (b), the widths in the short direction of the first magnetic sensing part 11b and the second magnetic sensing part 12b in the first detection part 1b in the second embodiment are different. ing. That is, the width W1 in the short direction of the first magnetic sensing part 11b is configured to be narrower than the width W2 in the short direction of the second magnetic sensing part 12b. The length L1 in the longitudinal direction of the first magnetic sensing part 11b is configured to be shorter than the length L2 in the longitudinal direction of the second magnetic sensing part 12b. The widths in the short direction of the first magnetic sensing part 11b and the second magnetic sensing part 12b are indicated by W1 and W2, respectively, and there is a relationship of W1 <W2.

  As described above, FIGS. 6A, 6B, 7A, and 7B show the first and second magnetosensitive portions 11a, 11b, and 12a having different sensitivities to the magnetic field in the first axial direction. , 12b is an example of the first detection unit 1a, 1b. The first and second magnetic sensitive portions 11a, 11b, 12a, and 12b have a magnetic sensitive axis in the X-axis direction. The first detectors 1a and 1b detect a magnetic field in the X-axis direction as a magnetic field in the first axial direction parallel to the substrate plane.

Moreover, in the example of the 1st detection part 1a in Embodiment 1 shown to FIG. 6 (a), (b), the 1st magnetic sensing part 11a is covered with the magnetic convergence part 20, and the sensitivity with respect to an external magnetic field The signal based on the resistance R depending on the material constituting the first magnetic sensing part 11a is always output. On the other hand, the second magnetic sensitive section 12a, in addition to the resistor R, and outputs a signal dependent on the resistance change amount ΔR that depends on the external magnetic field B _X in the X-axis direction.

To explain this in detail, the magnetic field components B _X in the X-axis direction is not input to the first sensitive portion 11a to be converged by the magnetic flux concentrator unit 20, to the second magnetically sensitive portion 12a Only entered. Here, on the input field components B _X, the magnetic field component in the X-axis direction is input to the second magnetically sensitive portion 12a represents the convergence rate for a magnetic field component in the X-axis direction by the magnetic flux concentrator 20 If the coefficient is h ₁ , h ₁ B _X is obtained. Further, the magnetic field component _B Y of the Y-axis direction, _{B z,} since the first and second magnetically sensitive portion 11a, the magnetic sensing axis direction 12a are not converted, first and second magnetically sensitive portion 11a, 12a Does not affect the output of. At this time, if the sensitivity to the external magnetic field in the X-axis direction is α, the resistance change amount ΔR = αh ₁ B _{X of} the second magnetic sensing portion 12a is obtained.

Here, when each magnetic sensing unit is driven at a constant voltage, the difference between the output signal S2 from the second magnetic sensing unit 12a and the output signal S1 from the first magnetic sensing unit 11a is:
S2-S1 = (R + αh 1 B X) / V CONST -R / V CONST
= Αh ₁ B _X / V _CONST
Thus, the external magnetic field BX in the X-axis direction can be derived based on the difference between the output signals of the first and second magnetic sensing units 11a and 12a.

Moreover, in the example of the 1st detection part 1b in Embodiment 2 shown to Fig.7 (a), (b), the length L1 of the longitudinal direction of the 1st magnetic sensing part 11b and the 2nd magnetic sensing part 12b is shown. , L2 and the widths W1 and W2 in the lateral direction are equal to each other. That is, the resistance R in the absence of a magnetic field of the first magnetic sensing part 11b and the second magnetic sensing part 12b is equal. On the other hand, since the widths W1 and W2 in the magnetic sensitive axis direction (short direction) of the first and second magnetic sensitive portions 11b and 12b are different, the resistance change amount ΔR depending on the external magnetic field is different. In the present embodiment 3, the sensitivity of the second magnetic sensitive section 12b to the external magnetic field component B _X in the X-axis direction is alpha, the sensitivity of the first magnetic sensitive sections 11b and beta, the second magnetic sensitive section resistance variation of 12b ΔR = αB _X, the amount of change in resistance [Delta] R = .beta.B _X of the first magnetic sensitive section 11b.

Here, when each magnetic sensing unit is driven at a constant voltage, the difference between the output signal S2 from the second magnetic sensing unit 12b and the output signal S1 from the first magnetic sensing unit 11b is:
S2-S1 = (R + αB X) / V CONST - (R + βB X) / V CONST
= (Α−β) B _X / V _CONST
Next, the first and second magnetically sensitive portion 11b, based on the difference of 12b output signals, it is possible to derive the external magnetic field B _X in the X-axis direction.

  In such a first detection unit 1a, 1b, a first axis parallel to the substrate plane based on the difference between the output signals S1, S2 of the first and second magnetic sensing units 11a, 11b, 12a, 12b. A signal corresponding to the magnetic field in the direction is output. The first detection unit 1c outputs a signal corresponding to the magnetic field in the first axial direction parallel to the substrate plane based on the output signals S3 and S4 of the third and fourth magnetic sensing units 11c and 12c. To do.

  8A and 8B, the first detection unit 1c according to the third embodiment includes third and fourth magnetosensitive units 11c, 11c having antimagnetic axes that are antiparallel to the magnetic field in the first axial direction. 12c, the magnetic sensing axis of the third magnetic sensing unit 11c in the first detection unit 1c is in the + X-axis direction, and the magnetic sensing axis of the fourth magnetic sensing unit 12c is in the -X-axis direction, The magnetic sensitive axis of each magnetic sensitive part is configured to be antiparallel. The widths in the short direction of the third magnetic sensing part 11c and the fourth magnetic sensing part 12c are indicated by W3 and W4, respectively, and there is a relationship of W3 = W4.

Moreover, in the example of the 1st detection part 1c in Embodiment 3 shown to Fig.8 (a), (b), the magnetosensitive axis of the 3rd magnetosensitive part 11c is a + X-axis direction, and a 4th sensitivity. The magnetic sensitive axis of the magnetic part 12c is in the -X axis direction, and the magnetic sensitive axis of each magnetic sensitive part is antiparallel (180 degrees different). In the third embodiment, each resistance change amount with respect to the external magnetic field component B _{X in} the X-axis direction of each magnetic sensing unit is set to be equal to αB _X.

When each magnetic sensing unit is driven at a constant voltage, the difference between the output signal S3 from the third magnetic sensing unit 11c and the output signal S4 from the fourth magnetic sensing unit 12c is:
S3-S4 = (R + αB _X ) / V _CONST − (R−αB _X ) / V _CONST
= 2αB _X / V _CONST
Next, third and fourth magnetically sensitive portion 11c, based on the difference of 12c output signals, it is possible to derive the external magnetic field B _X in the X-axis direction.

  As described above, the first detection units 1a to 1c in the magnetic sensors of the first to third embodiments depend on the material depending on the difference in output signals from the sets of the magnetosensitive units having different magnetoresistive sensitivities to the external magnetic field. It is understood that since the resistance R to be canceled is canceled and only the resistance change amount ΔR is output, it is possible to minimize the influence of the external temperature and to detect the magnetic field in the magnetosensitive axis direction. In addition, by designing the shape, size, etc. of each magnetic sensing part, it is possible to provide a detection part with an arbitrary sensitivity.

<Second detection unit>
FIGS. 9A and 9B are configuration diagrams for explaining the second detection unit in the magnetic sensor according to the fourth embodiment of the present invention, in which reference numeral 13a denotes a fifth magnetic sensing unit, and 14a denotes A sixth magnetic sensing unit, 21 is a first magnetic converging unit, 22 is a second magnetic converging unit, and 23 is a third magnetic converging unit.

  In the fourth embodiment, the second detection unit 2 detects the magnetic field in the first axial direction in order to detect the magnetic field in the second axial direction parallel to the substrate plane and perpendicular to the first axial direction. And fifth and sixth magnetosensitive portions 13a and 14a having the same sensitivity to the magnetic field in the first axial direction, and magnetic paths disposed in the vicinity of the fifth and sixth magnetosensitive portions 13a and 14a. It is comprised from the 1st thru | or 3rd magnetic convergence part 21 thru | or 23 which form. The widths in the short direction of the fifth magnetic sensing portion 13a and the sixth magnetic sensing portion 14a are indicated by W5 and W6, respectively, and there is a relationship of W5 = W6.

With this configuration, the second detection unit 2 is parallel to the substrate plane and perpendicular to the first axial direction based on the difference between the output signals S5 and S6 of the fifth and sixth magnetic sensing units 13a and 14a. A signal corresponding to the magnetic field in the second axial direction is output.
The fifth and sixth magnetic sensing portions 13a and 14a have a magnetic sensitive axis in the X-axis direction. Based on the difference between the output signals S5 and S6 of the fifth and sixth magnetic sensing units 13a and 14a, the second detection unit 2 is a second axis parallel to the substrate plane and perpendicular to the first axial direction. as the direction of the magnetic field, sensing the magnetic field B _Y of the Y-axis direction.

The second detection unit 2 includes fifth and sixth magnetic sensing units 13a and 14b having the same sensitivity to a magnetic field in the X-axis direction, and first to third magnetic focusing units 21 to 23.
When the first to third magnetic converging units 21 to 23 input magnetism in the longitudinal direction of the second magnetic converging unit 22, the first magnetic converging unit 21 and the second magnetic converging unit 21 are connected to the second magnetic converging unit 22. Are arranged such that magnetic paths of magnetic flux components are formed from the magnetic converging unit 22 to the third magnetic converging unit 23, respectively.

  Further, when the magnetic sensor is viewed in plan, from the first virtual midline L21 between the first magnetic converging part 21 and the second magnetic converging part 22, the longitudinal midline L13 of the fifth magnetic sensing part 13a is obtained. The distance between the middle lines MW1 and the second virtual center line L23 between the second magnetic converging part 22 and the third magnetic converging part 23 to the middle line L14 in the longitudinal direction of the sixth magnetic sensing part 14a. The midline distance MW2 is equal to each other.

Further, the first and third magnetic converging units 21 and 23 in the second detection unit 2 are line symmetric with respect to the virtual midline L22 in the longitudinal direction of the second magnetic converging unit 22 when viewed in plan. In addition, a virtual line segment L10 connecting the centers C1 and C3 of the first and third magnetic converging parts 21 and 23 is arranged at a position intersecting with a part other than the center C2 of the second magnetic converging part 22. ing.
In the example of the second detection unit 2 shown in FIGS. 9A and 9B, the magnetic field component B _{X in the} X-axis direction is converged by the first to third magnetic convergence units 21 to 23, The same input is made to the fifth and sixth magnetic sensing portions 13a and 14a. When the convergence rate of the magnetic field component in the X axis direction to be inputted to h _2, the fifth and sixth magnetic sensing part 13a, h ₂ BX is input as a magnetic field component in the X-axis direction relative to 14a.

Magnetic field component B _Y of the Y-axis direction is first once converged by the first and third magnetic flux concentrator 21, 23, both flows to the second magnetic flux concentrator 22. That is, for the fifth magnetic sensing part 13a, the fifth magnetic sensing part 13a is converted into a direction parallel to the magnetic sensing axis direction (X direction) of the fifth magnetic sensing part 13a, and for the sixth magnetic sensing part 14a, The sixth magnetic sensitive part 14a is converted into the anti-parallel direction (−X direction) with respect to the magnetic sensitive axis direction. Assuming that the conversion rate of the input magnetic field component in the Y-axis direction in the X-axis direction is k ₂ , k ₂ B _Y as the magnetic field component in the X-axis direction for the fifth and sixth magnetic sensitive portions 13a and 14a. Is entered.

Since the magnetic field component B _{Z in the} Z-axis direction is converged by the first to third magnetic converging units 21 to 23, both the fifth and sixth magnetic sensing units 13a and 14a are sensitive. It is converted into a direction parallel to the magnetic axis direction (−X direction). When the conversion of the X-axis direction of the magnetic field component in the Z axis direction to be inputted to the l _2, the fifth and sixth magnetic sensitive sections 13a, l ₂ B _Z as a magnetic field component in the X-axis direction with respect to 14a Is entered.

Here, when the sensitivity of the fifth and sixth magnetic sensing parts 13a and 14a in the X-axis direction is κ and each magnetic sensing part is driven at a constant voltage, the output signal S6 from the sixth magnetic sensing part 14a and the The difference of the output signal S5 from the magnetic sensing unit 13a of 5 is
S6-S5 = (R + κh 2 B X -κk 2 B Y -κl 2 B Z) / V CONST
_{- (R + κh 2 B X} + κk 2 B Y -κl 2 B Z) / V CONST
= -2κh _{2 BY} / V _CONST
Next, fifth and sixth magnetic sensing part 13a, based on the difference of 14a output signal of, it is possible to derive the external magnetic field B _Y of the Y-axis direction.

  The signs of the magnetic fields applied to the fifth and sixth magnetic sensing units 13a and 14a are reversed by the effects of the first to third magnetic converging units 21 to 23, and thus the fifth and sixth magnetic sensing units 13a. , 14a cancels the material-dependent resistance R and outputs only the resistance change ΔR, thereby minimizing the influence of external temperature and perpendicular to the magnetosensitive axis direction on the substrate plane. It becomes possible to detect a magnetic field in a parallel direction.

<Third detection unit>
FIGS. 10 (a) and 10 (b) are configuration diagrams of a third detection unit in Embodiment 5 of the magnetic sensor according to the present invention, and FIGS. 11 (a) and 11 (b) are diagrams of the magnetic sensor according to the present invention. The block diagram for demonstrating the 3rd detection part in Embodiment 6 is shown. In the figure, reference numeral 15a denotes a seventh magnetic sensing part, 16a denotes an eighth magnetic sensing part, 24 denotes a fourth magnetic convergence part, and 25 denotes a fifth magnetic convergence part.

  10 (a) and 10 (b), the third detector 3a in the fifth embodiment is arranged in the first axial direction in order to detect a magnetic field in the third axial direction perpendicular to the substrate plane. Seventh and eighth magnetic sensing portions 15a and 16a having a magnetic sensing axis and equal sensitivity to a magnetic field in the first axial direction, and disposed in the vicinity of the seventh and eighth magnetic sensing portions 15a and 16a. And a fourth magnetic converging part 24 forming a magnetic path. The widths in the short direction of the seventh magnetic sensing portion 15a and the eighth magnetic sensing portion 16a are indicated by W7 and W8, respectively, and there is a relationship of W7 = W8.

The fourth magnetic converging unit 24 is disposed so as to cover the gap between the seventh and eighth magnetic sensing units 15a and 16a in the third detection unit 3a.
Further, in FIGS. 11A and 11B, the third detection unit 3b in the sixth embodiment detects the first axis in order to detect the magnetic field in the third axial direction perpendicular to the substrate plane. The seventh and eighth magnetosensitive portions 15a and 16a having a magnetosensitive axis in the direction and having the same sensitivity to the magnetic field in the first axial direction, and in the vicinity of the seventh and eighth magnetosensitive portions 15a and 16a It is comprised from the 4th and 5th magnetic convergence parts 24 and 25 which are arrange | positioned and form a magnetic path. The widths in the short direction of the seventh magnetic sensing portion 15a and the eighth magnetic sensing portion 16a are indicated by W7 and W8, respectively, and there is a relationship of W7 = W8.

Moreover, the 4th and 5th magnetic convergence parts 24 and 25 are arrange | positioned so that the outer side of the 7th and 8th magnetic sensing parts 15a and 16a in the 3rd detection part 3b may be covered.
Further, the seventh and eighth magnetic sensing parts 15a and 16a in the third detection parts 3a and 3b are virtual connecting the centers of the seventh and eighth magnetic sensing parts 15a and 16a when viewed in plan. The line segment L56 is perpendicular to the virtual midline L40 in the longitudinal direction of the fourth magnetic flux concentrator 24. Moreover, in the 3rd detection part 3b, it is parallel to the virtual line segment L50 which connects the centers of the 4th and 5th magnetic convergence parts 24 and 25. FIG.

With such a configuration, the third detection units 3a and 3b output signals corresponding to the magnetic field in the third axial direction based on the difference between the outputs S7 and S8 of the seventh and eighth magnetic sensing units 15a and 16a. To do.
In addition, the seventh and eighth magnetic sensing units 15a and 16a of the third detection unit 3a in the magnetic sensor of the fifth embodiment shown in FIGS. 10A and 10B have the magnetic sensing axes in the X-axis direction. Have. The third detection unit 3a is based on the difference between the output signals S7 and S8 of the seventh and eighth magnetic sensing units 15a and 16a as a magnetic field in the third axial direction perpendicular to the substrate plane. detecting the direction of the magnetic field _{B Z.}

  The third detection unit 3a of the fifth embodiment includes the seventh and eighth magnetic sensing units 15a and 16a having the same sensitivity to the magnetic field in the X-axis direction, and the fourth magnetic convergence unit 24. . In the seventh and eighth magnetic sensing portions 15a and 16a, when the magnetic sensor is viewed in plan, an imaginary line segment L56 connecting the centers of the seventh and eighth magnetic sensing portions 15a and 16a is the fourth magnetic field. The convergence portion 24 is perpendicular to the virtual center line L40 in the longitudinal direction.

Further, FIG. 10 (a), the magnetic field component B _X in the X-axis direction in the example of the third detection unit 3a in the embodiment 5 shown in (b) is converged by the fourth magnetic converging section 24 of the seventh And the eighth magnetic sensing portions 15a and 16a are equally input. When the convergence rate of the magnetic field component in the X axis direction to be inputted to h _3, sensitive portion 15a of the seventh and 8, h ₃ B _X is input as the magnetic field component in the X-axis direction relative to 16a. The seventh and eighth magnetic sensing portions 15a and 16a are insensitive to the magnetic field component in the Y-axis direction.

Magnetic field component B _Z in the Z-axis direction, since it is converged by the fourth magnetic converging section 24 of, for seventh sensitive portion 15a, is converted into a parallel to the magnetic sensing axis direction (+ X direction), the The eight magnetic sensing parts 16a are converted to anti-parallel (−X direction) to the magnetic sensing axis direction. When the conversion of the X-axis direction of the magnetic field component in the Z axis direction to be inputted to the l _3, for the seventh sensitive portion 15a, l ₃ B _Z is input as the magnetic field component in the X-axis direction, -L ₃ B _Z is input to the eighth magnetic sensing portion 16a as the magnetic field component in the X-axis direction.

Here, when the sensitivity of the seventh and eighth magnetic sensing parts 15a, 16a in the X-axis direction is τ and each magnetic sensing part is driven at a constant voltage, the output signal S7 from the seventh magnetic sensing part 15a and the The difference of the output signal S8 from the magnetic sensing unit 8 is
S7-S8 = (R + τh ₃ B _X + τl ₃ B _Z ) / V _CONST
− (R + τh ₃ B _X −τl ₃ B _Z ) / V _CONST
= 2τl ₃ B _Z / V _CONST
Next, sensitive portion 15a of the seventh and eighth, based on the difference of 16a output signal of, it is possible to derive the external magnetic field B _Z of the Z-axis direction.

In addition, the seventh and eighth magnetic sensing units 15a and 16a of the third detection unit 3b in the magnetic sensor of the sixth embodiment shown in FIGS. 11A and 11B have the magnetic sensing axes in the X-axis direction. Have. The third detection unit 3b uses the Z axis as a magnetic field in the third axial direction perpendicular to the substrate plane based on the difference between the output signals S7 and S8 of the seventh and eighth magnetic sensing units 15a and 16a. detecting the direction of the magnetic field _{B Z.}

  The third detection unit 3b of the sixth embodiment includes seventh and eighth magnetic sensing units 15a and 16b having the same sensitivity to the magnetic field in the X-axis direction, and the fourth and fifth magnetic convergence units 24 and 25. It is composed of When the magnetic sensor is viewed in plan, the seventh and eighth magnetic sensing portions 15a and 16a have virtual line segments L56 connecting the centers of the seventh and eighth magnetic sensing portions 15a and 16a. 5 is parallel to an imaginary line segment L50 connecting the centers of the magnetic converging portions 24 and 25.

Further, FIG. 11 (a), the by the third magnetic field component _{B X} in the X-axis direction in the example of the detection portion 3b, fourth and fifth magnetic convergence portions 24 and 25 in the embodiment 6 shown in (b) It is converged and inputted equally to the seventh and eighth magnetic sensing parts 15a, 16a. When the convergence rate of the magnetic field component in the X axis direction to be inputted to h _3, with respect to the seventh and eighth magnetic sensitive sections 15a, 16a, h ₃ B _X is input as the magnetic field component in the X-axis direction . The seventh and eighth magnetic sensing portions 15a and 16a are insensitive to the magnetic field component in the Y-axis direction.

Since the magnetic field component B _{Z in the} Z-axis direction is converged by the fourth and fifth magnetic converging units 24 and 25, it is anti-parallel to the seventh magneto-sensitive unit 15a (−X Direction), and the eighth magnetic sensing portion 16a is converted parallel to the magnetic sensitive axis direction (+ X direction). Assuming that the conversion rate of the input magnetic field component in the Z-axis direction to the X-axis direction is l ₃ , −l ₃ B _Z is input as the magnetic field component in the X-axis direction to the seventh magnetic sensing unit 15a. In addition, l ₃ B _Z is input as the magnetic field component in the X-axis direction to the eighth magnetic sensing unit 16a.

Here, when the sensitivity of the seventh and eighth magnetic sensing parts 15a, 16a in the X-axis direction is τ and each magnetic sensing part is driven at a constant voltage, the output signal S8 from the eighth magnetic sensing part 16a and the The difference of the output signal S7 from the magnetic sensing unit 15a of 7 is
S8−S7 = (R + τh ₃ B _X + τl ₃ B _Z ) / V _CONST
− (R + τh ₃ B _X −τl ₃ B _Z ) / V _CONST
= 2τl ₃ B _Z / V _CONST
Next, sensitive portion 15a of the seventh and eighth, based on the difference of 16a output signal of, it is possible to derive the external magnetic field B _Z of the Z-axis direction.

  As described above, since the signs of the magnetic fields applied to the seventh and eighth magnetic sensing units 15a and 16a are reversed by the effects of the fourth and fifth magnetic focusing units 24 and 25, the seventh and eighth magnetic sensing units 15a and 16a are reversed. Since the resistance R depending on the material is canceled by the difference between the output signals of the magnetic parts 15a and 16a and only the resistance change ΔR is output, the influence of the external temperature is minimized and perpendicular to the direction of the magnetic sensitive axis. It becomes possible to detect a magnetic field perpendicular to the substrate plane.

The first to fourth magnetic sensitive portions 11a, 11c, 12a to 12c are configured so that the width in the short direction is narrower than the width in the short direction of the fifth to eighth magnetic sensitive portions 13a to 16a. Also good.
The first and second magnetic sensing portions 11a, 12a, the third and fourth magnetic sensing portions 11c, 12c, the fifth and sixth magnetic sensing portions 13a, 13b, 14a, 14b, and the seventh and eighth. It is preferable that the electric resistance of each set of the magnetic sensitive portions 15a, 15b, 16a, and 16b in the absence of a magnetic field be equal.

<Calculation unit>
The magnetic sensor according to the present invention includes a difference between output signals of the first and second or third and fourth magnetic sensing portions 11a, 12a / 11b, 12b / 11c, and 12c, and a difference between the fifth and sixth output signals. It is preferable to include an arithmetic unit capable of outputting the difference between the output signals of 13a, 14a / 13b, 14b, and the seventh and eighth magnetic sensing units 15a, 16a / 15b, 16b.
Next, specific examples of the magnetic sensor of the present invention will be described.

FIGS. 12A and 12B are configuration diagrams for explaining the first embodiment of the magnetic sensor according to the present invention, and the first detection unit shown in FIG. 6A is applied. The second detection unit shown in FIG. 9 was applied, and the third detection unit shown in FIG. 10 was applied.
As the magnetic sensitive portions 11a, 12a to 15a, 16a, GMR elements formed by laminating a spin valve type pinned layer, a conductive layer, and a free layer are used.

In the magnetic sensor of the first embodiment, the first magnetic sensing part 11a in the first detection part 1a is covered with the magnetic converging part 21, and the second magnetic sensing part 12a is the first sensing part on the substrate plane. It is attached to the magnetic part 11a.
Further, as can be seen from FIG. 12A, the first and third magnetic converging units 21 in the second detecting unit 2 between the first magnetic sensing unit 11a and the second magnetic sensing unit 12a, 23 is symmetric with respect to the virtual midline L22 in the longitudinal direction of the second magnetic converging part 22, and the virtual line segment connecting the centers C1 and C3 of the first and third magnetic converging parts 21 and 23 is provided. L <b> 10 is arranged at a position that intersects with a part other than the center C <b> 2 of the second magnetic convergence unit 22.

Further, a fourth magnetic converging unit 24 is disposed adjacent to the second magnetic sensing unit 12a so as to cover the gap between the seventh and eighth magnetic sensing units 15a and 16a in the third detection unit 3. .
Further, the magnetic sensing portions 11a, 12a to 15a, 16a have a magnetic sensitive axis with respect to the X-axis direction, and are arranged so that the respective magnetic sensitive axes are parallel to each other.
The magnetic sensing part 11a is magnetically shielded by the magnetic converging part 21 installed on the substrate, and when the magnetic sensor is viewed in plan, the magnetic sensing part 11a, 12a has a length W in the magnetic sensitive axis direction, The ratio of the length L in the direction parallel to the substrate surface and perpendicular to the magnetic sensitive axis direction (W1: L1 and W2: L2) is arranged to be equal. That is, the resistances R of the first and second magnetic sensing parts when no magnetic field is applied are equal. The first magnetic sensing part is not particularly limited as long as it is covered by the magnetic converging part, but it is covered by any of the first to fourth from the viewpoint of reducing the chip area. Is preferred.

The magnetic converging units 21 to 23 in the second detection unit are symmetrical with respect to a virtual midline in the longitudinal direction of the second magnetic converging unit when the magnetic sensor is viewed in plan, An imaginary line segment connecting the centers of the third magnetic converging portions is arranged at a position where it intersects with a portion other than the center of the second magnetic converging portions.
The fifth magnetic sensing part 13a is arranged between the magnetic focusing parts 21 and 22, and the sixth magnetic sensing part 14a is arranged between the magnetic focusing parts 22 and 23, and the fifth magnetic sensing part 13a. And the sixth magnetosensitive portion 14a coincide with each other in the magnetosensitive axis direction, and the middle lines of the fifth magnetosensitive portion 13a and the sixth magnetosensitive portion 14a coincide with each other. The imaginary line segment connecting the middle line and the centers of the magnetic converging part 21 and the magnetic converging part 23 is arranged in parallel.

Further, when the magnetic sensor is viewed in plan, the length W of the fifth and sixth magnetic sensing portions 13a and 14a in the direction of the magnetic sensitive axis and the length L in the direction parallel to the substrate surface and perpendicular to the direction of the magnetic sensitive axis. The ratios (W5: L5 and W6: L6) are equal. That is, the resistances R of the fifth and sixth magnetic sensing portions when no magnetic field is applied are equal.
The seventh and eighth magnetic sensing portions 15 and 16 are provided on both sides of the magnetic converging portion 24 with the longitudinal middle line of the magnetic converging portion and the longitudinal direction of the seventh and eighth magnetic sensing portions 15 and 16. They are arranged so that the distance from the middle line is equal. Further, when the magnetic sensor is viewed in plan, the length W in the direction of the magnetic sensitive axis of the seventh and eighth magnetic sensitive portions 15 and 16 and the length L in the direction parallel to the substrate surface and perpendicular to the direction of the magnetic sensitive axis. The ratios (W7: L7 and W8: L8) are equal to each other. That is, the resistances R of the fifteenth and sixteenth magnetic sensing portions when no magnetic field is applied are equal. Note that the width in the short direction of each magnetic sensing portion is in a relationship of W1 = W2 = W5 = W6 = W7 = W8.

  The difference between the output signals from the first and second magnetic sensing portions 11a and 12a in such a configuration, and the difference between the magnetic field components in the direction of the magnetic sensitive axis and the output signals from the fifth and sixth magnetic sensing portions 13a and 14a. According to the magnetic field component perpendicular to the substrate plane and in the direction parallel to the substrate plane, and according to the difference between the output signals in the sensitivity axis direction from the seventh and eighth magnetic sensing portions 15a and 16a. Each signal can be output.

Specifically, each detection unit is driven at a constant voltage, and a magnetic field B (X, Y, Z-axis direction components B _X , B _Y , B _Z ) is applied to the magnetic sensor.
The first detector
S2-S1 (S4-S3) = αh ₁ B _X / V _CONST
And the second detection unit
S6-S5 = 2κk _{2 BY} / V _CONST
And the third detection unit
S7-S8 = 2τl ₃ B _Z / V _CONST
Is output.

That is, B _X , B _Y , and B _Z can be derived by the first to third detection units. Further, from the above formula, by setting the sensitivities α, κ, and τ of the magnetic sensing units of the first to third detection units to desired values, the desired values can be obtained for the respective directions of the X, Y, and Z axes. It will be appreciated that sensitivity and range magnetic sensors are feasible. As another method, h _1, k ₂ , and l ₃ are desired by making the composition, size, and distance from each magnetic sensing part of the first to third detection parts desired. It is understood that a magnetic sensor having a desired sensitivity and range in each direction of the X, Y, and Z axes can also be realized by setting the value of.

  FIGS. 13A and 13B are configuration diagrams for explaining the magnetic sensor according to the second embodiment of the present invention, in the direction of the magnetosensitive axis of the seventh and eighth magnetosensitive parts of the third detecting unit. Example 1 is the same as Example 1 except that the width in the (X-axis direction) is widened. That is, the width in the short direction of the seventh and eighth magnetic sensing portions 15b, 16b is configured wider than the width in the short direction of the first to sixth magnetic sensitive portions 11a to 14a. The width in the short direction of each magnetic sensitive part is in a relationship of W1 = W2 = W5 = W6 <W7 = W8.

  As described above, since the widths of the seventh and eighth magnetic sensing parts are increased, the sensitivity is higher than that of the first, second, fifth, and sixth magnetic sensing parts, and thus the sensitivity in the Z-axis direction is high. It becomes a magnetic sensor.

  FIGS. 14A and 14B are configuration diagrams for explaining a magnetic sensor according to a third embodiment of the present invention. The first detector shown in FIG. 7A is applied except that it is applied. Similar to Example 1. That is, the width of the first magnetic sensing unit 11b and the second magnetic sensing unit 12b in the first detection unit 1b is configured to have different widths in the short direction, and the first magnetic sensing unit 11b has a short width. The width W1 in the direction is configured to be narrower than the width W2 in the short direction of the second magnetic sensing portion 12b. Note that the width in the short direction of each magnetic sensing part is in a relationship of W1 <W2 = W5 = W6 = W7 = W8.

  As described above, since the first detection unit shown in FIG. 7A is applied, the first and second magnetic sensing units do not receive the temperature characteristic of the magnetic flux concentrating plate. Magnetic sensor.

FIGS. 15A and 15B are configuration diagrams for explaining a magnetic sensor according to a fourth embodiment of the present invention. The third detection unit shown in FIG. 11A is applied except that it is applied. Similar to Example 1. That is, the 4th and 5th magnetic convergence parts 24 and 25 are arrange | positioned so that the outer side of the 7th and 8th magnetic sensing parts 15a and 16a in the 3rd detection part 3b may be covered. Note that the width in the short direction of each magnetic sensing portion is in a relationship of W1 = W2 = W5 = W6 = W7 = W8.
As described above, by applying the third detection unit shown in FIG. 11A, the second magnetic sensing unit is independent from other magnetic sensing units. Becomes easy.

  FIGS. 16A and 16B are configuration diagrams for explaining a magnetic sensor according to a fifth embodiment of the present invention. In the drawing, reference numerals 13b and 14b denote fifth and sixth magnetic sensing portions, and 15b and 16b. Indicates seventh and eighth magnetic sensing portions. The width of the magnetic sensing axis direction (X-axis direction) of the seventh and eighth magnetic sensing units of the third detection unit is widened, and the magnetic sensing axes of the fifth and sixth magnetic sensing units of the second detection unit. Example 1 is the same as Example 1 except that the direction width is narrowed. That is, the width in the short direction of the fifth and sixth magnetic sensing parts 13b and 14b in the second detection unit 2 is the first, second, fifth to eighth magnetic sensing parts 11a, 11c to 12a to 12c and 15a, 16a are configured to be narrower than the width in the short direction. The width in the short direction of each magnetic sensing part is in a relationship of W5 = W6 <W1 = W2 <W7 = W8.

Further, the width in the short direction of the first and second magnetic sensitive portions 11a and 12a, the width in the short direction of the fifth and sixth magnetic sensitive portions 13b and 14b, and the seventh and eighth magnetic sensitive portions. You may comprise so that the width | variety of the transversal direction with the parts 15b and 16b may each differ.
Thus, by increasing the width of the seventh and eighth magnetic sensing parts, the sensitivity to the magnetic field component in the Z-axis direction as a magnetic sensor is improved, and the width of the fifth and sixth magnetic sensing parts is reduced. This improves the detectable range for the magnetic field component in the Y-axis direction. That is, even if the GMR elements having the same structure are used as the first, second, and fifth to eighth magnetic sensing parts from the magnetic sensor according to the fifth embodiment, the width of each magnetic sensing part is set to a desired value. It is understood that it is possible to easily design a magnetic sensor in which the sensitivity and range in each axial direction have desired values.

1a, 1b, 1c 1st sensing part 11 thru | or 16 Sensitive part 11a, 11b 1st sensing part 12a, 12b 2nd sensing part 11c 3rd sensing part 12c 4th sensing part 13a, 13b 5th magnetic sensing part 14a, 14b 6th magnetic sensing part 15a, 15b 7th magnetic sensing part 16a, 16b 8th magnetic sensing part 20 Magnetic converging part 21 1st magnetic converging part 22 2nd magnetism Converging unit 23 Third magnetic converging unit 24 Fourth magnetic converging unit 25 Fifth magnetic converging unit 31 Substrate 32, 301, 306 Insulating film 101, 305 Antiferromagnetic layer 102, 202, 304 Pinned layer (fixed layer)
103, 203 Cu layer (spacer layer)
104,204,302 Free layer (free rotation layer)
303 Conductive layer

Claims (20)

In a magnetic sensor capable of detecting a magnetic field in an arbitrary axial direction with respect to a substrate plane,
In order to detect a magnetic field in a first axial direction parallel to the substrate plane, the first and second magnetic sensors have a magnetosensitive axis in the first axial direction and have different sensitivities to the magnetic field in the first axial direction. A first detection unit comprising a second magnetic sensing unit or a third and fourth magnetic sensing unit whose magnetosensitive axes with respect to the magnetic field in the first axial direction are antiparallel;
In order to detect a magnetic field in a second axis direction parallel to the substrate plane and perpendicular to the first axis direction, the first axis direction has a magnetosensitive axis and the first axis direction First and third magnetic converging portions which are arranged in the vicinity of the fifth and sixth magnetic sensing portions and form a magnetic path. Two detectors;
In order to detect a magnetic field in a third axial direction perpendicular to the substrate plane, a seventh and a seventh sensor having a magnetosensitive axis in the first axial direction and equal in sensitivity to the magnetic field in the first axial direction. A third magnetic sensing portion comprising the eighth magnetic sensing portion and the fourth magnetic focusing portion or the fourth and fifth magnetic focusing portions arranged in the vicinity of the seventh and eighth magnetic sensing portions to form a magnetic path; And a magnetic sensor. The first detection unit is a signal corresponding to a magnetic field in the first axial direction based on a difference between output signals of the first and second magnetic sensing units or output signals of the third and fourth magnetic sensing units. Output
The second detection unit outputs a signal corresponding to the magnetic field in the second axial direction based on a difference between output signals of the fifth and sixth magnetic sensing units,
The said 3rd detection part outputs the signal according to the magnetic field of the said 3rd axial direction based on the difference of the output of the said 7th and 8th magnetic sensing part. Magnetic sensor. When the first to third magnetic converging units in the second detection unit input magnetism in the longitudinal direction of the second magnetic converging unit, the second magnetic converging unit outputs the first magnetism. Arranged so that magnetic paths of magnetic flux components are respectively formed from the converging unit and the second magnetic converging unit to the third magnetic converging unit,
When viewed in plan, the interline distance from the first virtual midline between the first magnetic converging part and the second magnetic converging part to the midline in the longitudinal direction of the fifth magnetic sensitive part, And the distance between the midlines from the second virtual midline between the second magnetic converging part and the third magnetic converging part to the midline in the longitudinal direction of the sixth magnetic sensitive part is equal to each other. The magnetic sensor according to claim 1 or 2.   When the seventh and eighth magnetic sensing units in the third detection unit are viewed in plan, a virtual line segment that connects the centers of the seventh and eighth magnetic sensing units is the fourth magnetic field. 4. The magnetism according to claim 1, wherein the magnetism is perpendicular to a virtual midline in a longitudinal direction of the converging portion or parallel to an imaginary line segment connecting the centers of the fourth and fifth magnetic converging portions. Sensor.   When the first magnetic sensing unit in the first detection unit is viewed in plan, the first magnetic sensing unit is covered with a magnetic converging unit, and the second magnetic sensing unit is on the substrate plane. The magnetic sensor according to claim 1, further comprising:   The magnetic sensor according to claim 5, wherein the magnetic converging unit is any one of the first to fifth magnetic converging units.   5. The magnetic sensor according to claim 1, wherein a width in a short direction of the first magnetic sensing unit and the second magnetic sensing unit in the first detection unit are different from each other.   In the first detection unit, the magnetic sensing axis of the third magnetic sensing unit is in the + X-axis direction, the magnetic sensing axis of the fourth magnetic sensing unit is in the -X-axis direction, and the magnetic sensing of each magnetic sensing unit. 5. The magnetic sensor according to claim 1, wherein the axes are antiparallel.   The first and third magnetic flux concentrators in the second detector are symmetrical with respect to a virtual midline in the longitudinal direction of the second magnetic convergent when viewed in plan, and 9. An imaginary line segment that connects the centers of the first and third magnetic flux concentrators is disposed at a position that intersects with a portion other than the center of the second magnetic flux convergent portion. The magnetic sensor in any one of.   The fourth magnetic flux converging unit is disposed so as to cover a gap between the seventh and eighth magnetic sensing units in the third detection unit. Magnetic sensor.   The said 4th and 5th magnetic convergence part is arrange | positioned so that the outer side of the said 7th and 8th magnetic sensing part in a said 3rd detection part may be covered, The any one of Claim 1 thru | or 9 characterized by the above-mentioned. A magnetic sensor according to claim 1. The first magnetic sensing unit in the first detection unit is covered with a magnetic converging unit, and the second magnetic sensing unit is provided alongside the first magnetic sensing unit on the substrate plane,
Between the first magnetic sensing unit and the second magnetic sensing unit, the first and third magnetic focusing units in the second detection unit are arranged in the longitudinal direction of the second magnetic focusing unit. An imaginary line segment that is line-symmetric with respect to the imaginary midline and that connects the centers of the first and third magnetic converging portions intersects with a portion other than the center of the second magnetic converging portion. Arranged,
The fourth magnetic flux converging unit is disposed adjacent to the second magnetic sensing unit so as to cover a gap between the seventh and eighth magnetic sensing units in the third detection unit. The magnetic sensor according to claim 1.   13. The magnetism according to claim 12, wherein a width in a short direction of the seventh and eighth magnetic sensitive parts is wider than a width in a short direction of the first to sixth magnetic sensitive parts. Sensor.   13. The magnetic sensor according to claim 12, wherein widths in a short direction of the first magnetic sensing unit and the second magnetic sensing unit in the first detection unit are different from each other.   The said 4th and 5th magnetic convergence part is arrange | positioned so that the outer side of the said 7th and 8th magnetic sensing part in a said 3rd detection part may be covered. Magnetic sensor.   The width in the short direction of the fifth and sixth magnetic sensing parts in the second detection unit is narrower than the width in the short direction of the first, second, and fifth to eighth magnetic sensing parts. The magnetic sensor according to claim 13.   The difference between the output signals of the first and second or third and fourth magnetic sensing units, the difference between the output signals of the fifth and sixth magnetic sensing units, and the seventh and eighth magnetic sensing units. The magnetic sensor according to claim 1, further comprising an arithmetic unit that outputs a difference between output signals.   2. The magnetism according to claim 1, wherein a width in a short direction of the first to fourth magnetic sensitive portions is narrower than a width in a short direction of the fifth to eighth magnetic sensitive portions. Sensor.   The width in the short direction of the first and second magnetic sensitive parts, the width in the short direction of the fifth and sixth magnetic sensitive parts, and the short width of the seventh and eighth magnetic sensitive parts The magnetic sensor according to claim 1, wherein widths in directions are different from each other.   No magnetic field of each of the first and second magnetic sensitive parts, the third and fourth magnetic sensitive parts, the fifth and sixth magnetic sensitive parts, and the seventh and eighth magnetic sensitive parts. The magnetic sensor according to claim 1, wherein the electrical resistance at the bottom is equal.

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