JP2007281505A - Magnetic sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetic sensor which suppresses offset variations when a strong magnetic field is applied, to consequently enhance the resistance characteristics to the strong magnetic field. <P>SOLUTION: The magnetic sensor 1 comprises GMR elements 11 to 14, 21 to 24 formed on a quartz substrate 2, wherein each GMR element is formed by a magnetoresistive element 31 and permanent magnet films 32, 32 which are connected to both ends of the magnetoresistive element 31. Magnetic field strengths in two axis directions can be detected by the magnetoresistive elements 31 to 31. The pinned magnetization direction of a pinned layer of the magnetoresistive element 31 forms an angle of 45° relative to the longitudinal direction of the magnetoreistive element 31. The pinned magnetization direction of the pinned layer is the same as the magnetization direction of the magnetized permanent magnet films 32, 32. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a magnetic sensor, and more particularly to a magnetic sensor that can suppress the movement of offset when a strong magnetic field is applied, and as a result, can improve the strong magnetic field resistance.

Conventionally, magnetic sensors using magnetoresistive elements such as giant magnetoresistive elements (hereinafter also referred to as GMR elements) have been proposed and put into practical use.
This GMR element includes a pinned layer whose magnetization direction is pinned in a predetermined direction, and a free layer whose magnetization direction changes in response to an external magnetic field, and when an external magnetic field is applied, It exhibits a resistance value corresponding to the relative relationship between the magnetization direction and the magnetization direction of the free layer, and an external magnetic field is detected by measuring this resistance value.
In such a magnetic sensor, in order to accurately detect a minute external magnetic field, the magnetization direction of each magnetic domain of the free layer when the external magnetic field is not applied to the magnetic sensor is set to a predetermined direction (hereinafter, This “predetermined orientation” is also referred to as “initial orientation”).

Therefore, in general, the shape of the free layer of the thin film in a plan view is a rectangle, and the long side (long axis) of the rectangle is aligned with the direction of the initial state so that the magnetization direction is aligned in the longitudinal direction. By utilizing shape anisotropy, the direction of magnetization of each magnetic domain of the free layer is made to coincide with the direction of the initial state. In addition, when the external magnetic field is extinguished, a bias magnet that is a permanent magnet film at both ends in the longitudinal direction of the free layer so that the magnetization direction of each magnetic domain of the free layer is stably restored to the initial state for a long period of time. A film is arranged, and the magnetic field in the same initial state is applied to the free layer by the bias magnet film.
In addition, in the AMR type magnetoresistive effect element, it is necessary to apply a bias magnetic field in order to increase the sensitivity. In order to apply this evenly to the four elements, the magnetoresistive effect element is 45 ° with respect to the substrate. An inclined magnetic sensor has been proposed (see, for example, Patent Document 1).
JP 05-1226577 A (paragraph number [0016], FIG. 5 (a))

By the way, in the conventional magnetic sensor, when an external magnetic field having a relatively large magnetic field smaller than the coercive force of the bias magnet film and having a direction opposite to the initial state is applied, each of the free layers The magnetization of the magnetic domain changes, and after that, even if the external magnetic field is extinguished, the magnetization direction of each magnetic domain in the free layer does not match (return to) the initial state, and the magnetic field detection accuracy deteriorates. was there.
In addition, it is difficult to form two or more magnetoresistive elements in which the magnetization directions of the pinned layers intersect each other on a minute substrate, and no single chip having such a configuration has been proposed. Therefore, there is a problem that the magnetic sensor cannot be reduced in size and the application range cannot be widened due to the restriction of the magnetization direction of the pinned layer.

Therefore, the present inventors have proposed a biaxial magnetic sensor using a GMR element that can be miniaturized and has a wide application range (Japanese Patent Application No. 2001-281703).
FIG. 26 is a plan view showing a biaxial magnetic sensor using a GMR element proposed by the present inventors. The magnetic sensor 101 includes a substantially square quartz substrate 102 having a predetermined thickness and the quartz sensor 102. X-axis GMR elements 111 to 114 constituting an X-axis magnetic sensor that detects a magnetic field in the X-axis direction formed on the substrate 102 and a magnetic field in the Y-axis direction that is formed on the quartz substrate 102 and orthogonal to the X-axis are detected. Y-axis GMR elements 121 to 124 constituting the Y-axis magnetic sensor.

The X-axis GMR elements 111 to 114 are arranged in pairs near the midpoint of each of the two sides orthogonal to the X-axis on the quartz substrate 102 so that the pair of elements are parallel to each other. Similarly, the Y-axis GMR elements 121 to 124 are arranged in pairs near the midpoint of each of the two sides orthogonal to the Y-axis on the quartz substrate 102 so that the pair of elements are parallel to each other.
These X-axis GMR elements 111 to 114 and Y-axis GMR elements 121 to 124 have exactly the same structure except that the arrangement on the quartz substrate 102 and the direction of the pinned magnetization of the pinned layer with respect to the quartz substrate 102 are different. It has.
Therefore, here, the structure of the X-axis GMR element 111 will be described as an example.

As shown in FIGS. 27 and 28, the X-axis GMR element 111 includes strip-like spin valve films 131, 131,... Arranged parallel to each other, and a hard ferromagnetic material such as CoCrPt having a high coercive force and a high squareness ratio. The bias magnet films 132, 132,...
Each spin valve film 131 has one end connected to one adjacent spin valve film 131 via a bias magnet film 132, and the other end connected to the other spin valve film 131 adjacent to the other spin valve film 131. As a result of the connection, the overall shape is in a zigzag shape.

As shown in FIG. 29, the spin valve film 131 includes a free layer F, a conductive spacer layer S made of Cu having a thickness of 2.4 nm (24 mm), a pinned layer PD made of CoFe, A pinning layer PN made of PtMn, and a capping layer C made of a metal thin film such as titanium (Ti) or tantalum (Ta) are sequentially laminated.
The free layer F is a layer in which the direction of magnetization changes according to the direction of the external magnetic field. The NiFe magnetic layer 131b having a thickness of 3.3 nm (33 Å) and the CoFe layer 131c having a thickness of about 1 to 3 nm (10 to 30 Å) stacked on the NiFe magnetic layer 131b are configured.
A bias magnetic field is applied to the free layer F in the Y-axis direction in FIG. 27 by the bias magnet film 132 in order to maintain the uniaxial anisotropy.

The spacer layer S is a metal thin film made of Cu or Cu alloy.
The CoZrNb amorphous magnetic layer 131a and the NiFe magnetic layer 131b are soft ferromagnetic materials, and the CoFe layer 131c prevents diffusion of Ni in the NiFe magnetic layer 131b and Cu in the spacer layer S.
The pinned layer PD is composed of a CoFe magnetic layer 131d having a thickness of 2.2 nm (22 mm). The CoFe magnetic layer 131d is pinned (fixed) in the negative X-axis direction by being back-exchanged and coupled to an antiferromagnetic film 131e described later.

The pinning layer PN is composed of an antiferromagnetic film 131e having a thickness of 24 nm (240 mm) made of a PtMn alloy containing 45 to 55 mol% of Pt laminated on the CoFe magnetic layer 131d. The antiferromagnetic film 131e is ordered as a result of applying a magnetic field in the negative X-axis direction.
The pinned layer PD and the pinning layer PN are collectively referred to as a pinned layer.
The structures of the X-axis GMR elements 112 to 114 and the Y-axis GMR elements 121 to 124 are the same as those of the X-axis GMR element 111 described above, and thus the description thereof is omitted.

Next, the magnetic characteristics of the X-axis GMR elements 111 to 114 and the Y-axis GMR elements 121 to 124 will be described.
As shown in FIG. 30, the X-axis GMR element 111 has an external magnetic field [Oe] that changes along the X-axis, as shown by the solid line in the drawing, the above-mentioned external magnetic field in the region of −Hk to + Hk. As shown by the broken line in the figure, an external magnetic field [Oe] that changes along the Y axis exhibits a hysteresis curve that is substantially constant in the regions on both sides of this range. Furthermore, it exhibits a substantially constant resistance value with respect to the external magnetic field.

In the X-axis GMR elements 111 and 112, as indicated by arrows in FIG. 26, the pinned magnetization direction of the pinned layer is the negative X-axis direction.
On the other hand, in the X-axis GMR elements 113 and 114, as indicated by arrows in FIG. 26, the pinned magnetization direction of the pinned layer is the X-axis positive direction.
In the Y-axis GMR elements 121 and 122, as indicated by arrows in FIG. 26, the pinned magnetization direction of the pinned layer is the Y-axis positive direction.
On the other hand, in the X-axis GMR elements 123 and 124, as indicated by arrows in FIG. 26, the pinned magnetization direction of the pinned layer is the negative Y-axis direction.

In the X-axis magnetic sensor (X-axis GMR elements 111 to 114), as shown in FIG. 31, the X-axis GMR elements 111 to 114 are full-bridge connected. In FIG. 31, arrows indicate the directions of pinned magnetization of the pinned layers of the X-axis GMR elements 111 to 114. In such a configuration, when Vxin + (here, 5V) is applied to one terminal and Vxin− (here, 0V) is applied to one terminal using a DC power supply, Vxout + is further transmitted from one terminal H to the other terminal. Vxout− is respectively taken out from the terminal L of this, and the taken out potential difference (Vxout + −Vxout−) is outputted as the sensor output Vxout.
As a result, as indicated by the solid line in FIG. 32, the X-axis magnetic sensor changes substantially in proportion to the external magnetic field in the range of −Hk to + Hk with respect to the external magnetic field that changes along the X-axis. The output voltage Vxout that is substantially constant in the regions on both sides of this range is shown.
On the other hand, for an external magnetic field that changes along the Y-axis, an output voltage Vxout of approximately “0 V” is shown, as indicated by a broken line in FIG.

As shown in FIG. 33, the Y-axis magnetic sensor (Y-axis GMR elements 121 to 124) is full-bridge connected to the Y-axis GMR elements 121 to 124 as shown in FIG. In such a configuration, when a DC power source is used to apply Vyin + (here, 5 V) to one terminal and Vyin- (here, 0 V) to the other terminal, Vyout + is further supplied from one terminal H to the other terminal. Vyout− is respectively taken out from the terminal L of this, and the taken out potential difference (Vyout + −Vyout−) is outputted as the sensor output Vyout.
As a result, as indicated by the broken line in FIG. 34, the Y-axis magnetic sensor changes substantially in proportion to the external magnetic field in the range of −Hk to + Hk with respect to the external magnetic field changing along the Y-axis. The output voltage Vyout that is substantially constant in the regions on both sides of this range is shown.
On the other hand, for an external magnetic field that changes along the X-axis, an output voltage Vyout of approximately “0 V” is shown as indicated by a solid line in FIG.

Next, a method for manufacturing the magnetic sensor 101 will be described.
First, as shown in FIG. 35, a plurality of films M for forming individual GMR elements are formed in an island shape on a rectangular quartz glass 141. When the quartz glass 141 is divided into individual quartz substrates 102 by cutting the quartz glass 141 along the break line B in a subsequent cutting step, the X-axis GMR elements 111 to 114 and the Y-axis GMR element 121 are separated. It is formed so as to be arranged at a position of ~ 124. In addition, alignment marks (positioning marks) 142 having a shape obtained by removing a cross from a rectangle are formed at four corners of the quartz glass 141.

  Next, as shown in FIG. 36 and FIG. 37, a rectangular metal plate 144 in which a plurality of through holes 143 having square openings are formed in a lattice shape is prepared, and each through hole 143 of the metal plate 144 is provided with each through hole 143. The rectangular permanent magnet pieces 145, 145,... Whose cross-sectional shape is substantially the same as the through-hole 143 are arranged so that the upper end surface of each permanent magnet piece 145 is parallel to the surface of the metal plate 144 and adjacent permanent magnet pieces. The magnet pieces 145 are inserted so as to have different polarities.

  Next, as shown in FIG. 38, a plate 151 made of transparent quartz glass having substantially the same shape as the metal plate 144 is prepared. In each of the four corners of the plate 151, a cross-shaped alignment mark (positioning mark) 152 for positioning in cooperation with the alignment mark 142 of the quartz glass 141 is formed. Further, in the quartz glass 151, alignment marks 153 corresponding to the outer shape of the permanent magnet 145 are formed at positions corresponding to the through holes 143, 143,.

Next, the upper end surfaces of the permanent magnet pieces 145, 145,... Of the magnet array are bonded to the lower surface of the plate 151 with an adhesive. At this time, the alignment mark 153 is used to position the permanent magnet pieces 145, 145,.
Thereafter, the metal plate 144 is removed from below. This produces a magnet array in which the permanent magnet pieces 145, 145,... Are arranged in a lattice pattern and the polarities of the upper ends of the adjacent permanent magnet pieces 145 are different from each other.
Next, as shown in FIG. 40, the film M of the quartz glass 141 is disposed so as to be in contact with the upper surface of the plate 151. The alignment between the quartz glass 141 and the plate 151 is performed by causing the alignment marks 142, 142,... And the alignment marks 152, 152,. Thereafter, the quartz glass 141 and the plate 151 are fixed using a plurality of fixtures 155 such as clips.

In this state, as shown in FIG. 41, a magnetic field is formed from the north pole of one permanent magnet piece 145 toward each south pole of the adjacent permanent magnet pieces 145, 145,. Therefore, as shown in FIG. 42, the films M, M,... Arranged around one permanent magnet piece 145 have a Y-axis positive direction, an X-axis positive direction, a Y-axis negative direction, and an X-axis negative direction. Directional magnetic field is applied.
Therefore, heat treatment is performed at 250 ° C. to 280 ° C. for 4 hours in a vacuum while the quartz glass 141 and the plate 151 are fixed with the fixture 155. Thereby, the pinned layer of the GMR element is ordered. Thereafter, the quartz glass 141 and the plate 151 are separated, a passivation film for protection and a polyimide film are formed, and the quartz glass 141 is cut along the break line B. Thereby, the magnetic sensor 101 is manufactured.

By the way, this biaxial geomagnetic sensor has an advantage that it can measure a magnetic field at the geomagnetic level without using a bias magnetic field, compared with a magnetic sensor having a structure in which a conventional AMR magnetoresistive element is inclined by 45 °. However, when a strong magnetic field is applied, the magnetization state changes and the offset of the bridge changes.
Therefore, a method is conceivable in which permanent magnets are attached to both ends of the GMR element to suppress the offset movement in the strong magnetic field. Specifically, a magnetic field larger than the coercive force Hc of the permanent magnet is applied in the longitudinal direction of the GMR element, that is, the longitudinal direction of the free layer, and the free layer is initialized simultaneously with the magnetization of the permanent magnet. In this method, the magnet array used in the above-described ordered heat treatment of the pinned layer can be used.

However, in this method, a magnetic field is applied in the direction perpendicular to the longitudinal direction of the GMR element during the regularized heat treatment, and a magnetic field is applied in the same direction as the longitudinal direction of the GMR element when the permanent magnet film is magnetized. Since it is necessary, the direction of the magnetic field to be applied is different in each step.
In addition, the magnet array is arranged so that the center of each cell on the quartz glass coincides with the center of gravity of the permanent magnet piece of the magnet array during the regularization heat treatment, and when the permanent magnet film is magnetized, Since the center of gravity of the permanent magnet piece is shifted from the four corners of the quartz glass so as to coincide with each other, the magnet array is displaced and the initialization direction is deviated, resulting in poor measurement accuracy. In use, the offset is likely to fluctuate when a strong magnetic field is applied.
Thus, although there is an effect of reducing hysteresis in a weak magnetic field of the GMR element, the stability of the offset is insufficient.
In addition, it is conceivable to restore the magnetization state moved by the strong magnetic field by embedding a thin film coil under the GMR element and applying an initialization magnetic field. It is insufficient.

  The present invention has been made in view of the above circumstances, and can provide a magnetic sensor capable of suppressing the movement of offset when a strong magnetic field is applied, and as a result, improving the magnetic field resistance. The purpose is to provide.

In order to solve the above-described problems, the present invention provides the following magnetic sensor.
That is, in the magnetic sensor of the present invention, at least one magnetoresistive effect element is formed on a substrate, and permanent magnet films are respectively connected to both ends of the magnetoresistive effect element. In the magnetic sensor for detecting the thickness, the pinned magnetization direction of the pinned layer of the magnetoresistive element and the longitudinal direction of the magnetoresistive element form an angle of 45 °, and the pin of the pinned layer A magnetic sensor characterized in that the direction of magnetization stopped is the same as the direction of magnetization after magnetization of a permanent magnet film.

  In this magnetic sensor, when the direction of the pinned magnetization of the pinned layer of the magnetoresistive effect element and the longitudinal direction of the magnetoresistive effect element form an angle of 45 °, a strong magnetic field is applied. Also, the movement of the bridge offset is suppressed. As a result, the magnetic field resistance can be improved.

  As described above, according to the magnetic sensor of the present invention, the pinned magnetization direction of the pinned layer of the magnetoresistive effect element and the longitudinal direction of the magnetoresistive effect element form an angle of 45 °. Even when a strong magnetic field is applied, the movement of the bridge offset can be suppressed, and the magnetic field resistance can be improved.

  Embodiments of the magnetic sensor of the present invention will be described with reference to the drawings.

“First Embodiment”
FIG. 1 is a plan view showing a magnetic sensor according to a first embodiment of the present invention, which is an example of a biaxial magnetic sensor using a GMR element.
The magnetic sensor 1 includes a substantially square quartz substrate 2 having a predetermined thickness, and X-axis GMR elements 11 to 11 that constitute an X-axis magnetic sensor that is formed on the quartz substrate 2 and detects a magnetic field in the X′-axis direction. 14 and Y-axis GMR elements 21 to 24 that constitute a Y-axis magnetic sensor that is formed on the quartz substrate 2 and detects a magnetic field in the Y′-axis direction orthogonal to the X′-axis. Specifically, the sensitivity directions of the X-axis magnetic sensor and the Y-axis magnetic sensor are in the directions of the X ′ axis and the Y ′ axis that form an angle of 45 ° with the X axis and the Y axis shown in FIG.
A silicon wafer may be used in place of the quartz substrate 2.

  The X-axis GMR elements 11 to 14 are arranged in pairs near the midpoint of each of the two sides orthogonal to the X-axis on the quartz substrate 2 so that the pair of elements are parallel to each other. Similarly, the Y-axis GMR elements 21 to 24 are arranged in pairs near the midpoint of each of the two sides orthogonal to the Y-axis on the quartz substrate 2 so that the pair of elements are parallel to each other.

  The X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24 are composed of a plurality of strip-like magnetoresistive effect elements 31 made of spin valve films arranged in parallel to each other, and the longitudinal direction of the magnetoresistive effect elements 31 Are formed by permanent magnet films 32 and 32 made of a thin film of a hard ferromagnetic material such as CoCrPt having a high coercive force and a high squareness ratio. The longitudinal direction of each of the permanent magnet films 32 and 32 forms an angle of 45 °.

The magnetoresistive effect element 31 is formed so that the major axis direction thereof is 45 ° with respect to the side of the quartz substrate 2 that is close thereto. Further, the permanent magnet films 32 and 32 are formed so that the major axis direction thereof is parallel to the adjacent sides of the quartz substrate 2 and the distances from the sides are different from each other.
Since the magnetization direction of the free layer of the magnetoresistive effect element 31 is the direction along the major axis, and the magnetization directions of the permanent magnet films 32 and 32 are also the direction along the major axis, the magnetoresistive effect element 31. The direction of magnetization of the free layer and the direction of magnetization of the permanent magnet films 32 and 32 are the same.

The pinned magnetization direction of the pinned layer of the magnetoresistive effect element 31 and the longitudinal direction of the magnetoresistive effect element 31 are 45 °. That is, the direction of the magnetic field during the regularization heat treatment and the longitudinal direction of the magnetoresistive effect element 31 are set to 45 °.
The pinned magnetization direction of the pinned layer of the magnetoresistive element 31 is the same as the magnetization direction of the permanent magnet films 32 and 32. That is, the direction of the magnetic field during the ordered heat treatment is the same as the direction of the magnetic field during magnetization.

The structure of the spin valve film itself is the same as that of the conventional spin valve films 131 of the X-axis GMR elements 111 to 114 and the Y-axis GMR elements 121 to 124. Description is omitted.
In these X-axis GMR elements 11 to 14 and Y-axis GMR elements 21 to 24, the magnetization direction of the pinned layer PD of the magnetoresistive effect element 31 and the magnetization direction of the permanent magnet film 32 are the same.
Further, the major axis direction of the free layer F of the magnetoresistive effect element 31 and the major axis direction of the permanent magnet film 32 are connected in an inclined state of 45 °.

Next, a method for manufacturing the magnetic sensor 1 will be described.
Similar to the conventional magnetic sensor 101, a plurality of permanent magnet films 32, 32 connected to individual GMR elements are formed in an island shape on a rectangular quartz glass. Here, as shown in FIG. 2, the region M in which the GMR elements defined by these films N and N are arranged is obtained by cutting the quartz glass 41 along the break line B in a later cutting step. When divided into the individual quartz substrates 2, they are formed so as to be arranged at the positions of the X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24.
In addition, alignment marks (not shown) are formed at the four corners of the quartz glass 41. After the formation of the permanent magnet films 32, 32, a film for constituting the GMR element is formed on the entire surface.

Next, as shown in FIG. 3, a metal plate 44 in which a plurality of through-holes 43 having square openings are formed in a lattice shape is prepared, and a cross-sectional shape is formed in each through-hole 43 of the metal plate 44. The rectangular permanent magnet film pieces 45, 45,... Having substantially the same shape as 43 are arranged so that the upper end surface of each permanent magnet piece 45 is parallel to the surface of the metal plate 44 and adjacent permanent magnet pieces 45. Insert them so that their polarities are different.
Next, a plate made of transparent quartz glass having substantially the same shape as the metal plate 44 is prepared.
The position of the alignment mark 153 corresponding to the position in the through hole 43 is the same as the position of the conventional plate.

On the other hand, the alignment marks 152 for positioning with the quartz glass later are shifted in the X-axis negative direction and the Y-axis negative direction by 1/2 of the side length of the quartz substrate 2 from the positions of the alignment marks 152. An alignment mark is formed at a position (hereinafter referred to as “half-shifted”).
The conventional alignment mark 152 and the alignment mark shifted by a half pitch may coexist.
The upper end surfaces of the permanent magnet pieces 45, 45,... Of the magnet array in which the permanent magnet pieces 45, 45,... Are arranged in a lattice shape are bonded to the lower surface of the plate with an adhesive. At this time, the alignment mark 153 is used to position the permanent magnet pieces 45, 45,.
Thereafter, the metal plate 44 is removed. Thereby, the permanent magnet pieces 45, 45,... Are arranged in a lattice pattern, and a magnet array in which the polarities of the adjacent permanent magnet pieces 45 are different is produced.

  Next, the quartz glass 41 is disposed so that the film M is in contact with the upper surface of the plate. The alignment between the quartz glass 41 and the plate is performed by making the alignment mark shifted by a half pitch of the plate and the conventional alignment mark of the quartz glass 41 coincide with each other. As a result, the four corners of the quartz substrate 2 serving as individual cells in the quartz glass 41 correspond to the positions of the center of gravity of the permanent magnet pieces 45, 45,. Thereafter, the quartz glass 41 and the plate are fixed using a plurality of fixtures such as clips.

Next, the ordering heat treatment of the pinning layer PN of the magnetoresistive effect element 31 and the pinning of the pinned layer PD accompanying this are performed.
In a state where the quartz glass 41 and the plate are fixed, as shown in FIG. 2, the permanent magnet pieces are arranged so that the polarities of the adjacent permanent magnet pieces 45 are different from each other at the four corners of the quartz substrate 2 to be divided by the subsequent cutting process. 45, 45, ... are arranged, a magnetic field is formed from one permanent magnet piece 45 (N pole) toward the other permanent magnet piece 45 (S pole). Since this magnetic field is parallel to each side of the quartz substrate 2, the magnetic field is applied to each film M in a direction inclined by 45 ° with respect to the major axis direction of the pin layer of the magnetoresistive effect element 31. .

Thereafter, heat treatment is performed at 250 ° C. to 280 ° C. for 4 hours in a vacuum while the quartz glass 41 and the plate are fixed with a fixture.
Thereby, the ordering heat treatment of the pinning layer PN can be performed among the pin layers of the magnetoresistive effect element 31 of each of the X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24. Thereby, the pinned layer PD is pinned by exchange coupling.
Here, the X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24 are patterned so as to have a predetermined shape, and connected to the permanent magnets 32 and 32 to form a spiral shape.
In this magnetic sensor 1, the X-axis sensitivity direction F 1 and the Y-axis sensitivity direction F 2 of the pin layer of the magnetoresistive effect element 31 are inclined at 45 ° with respect to each side of the quartz substrate 2 as shown in FIG. Direction.

Next, as shown in FIG. 6, the same magnet array is used, and the positions of the centers of gravity of the four corners of the quartz substrate 2 and the permanent magnet pieces 45, 45,... Coincide with each other without changing the position of the magnet array. In this state, the permanent magnet film 32 is magnetized.
Here, the application direction of the magnetic field in the magnetization of the permanent magnet film 32 is the same as the application direction of the magnetic field in the magnetization of the pinned layer P of the magnetoresistive effect element 31.
In this manner, the magnetic sensor 1 in which the pinned layer PD of the magnetoresistive element 31 is pinned and the permanent magnet film 32 is magnetized can be manufactured.

Figure 7 is a block diagram showing a bridge connection of the X-axis magnetic sensor of the magnetic sensor 1 (X-axis GMR elements 11 to 14), in FIG, _{X 1} is an element group consisting of X-axis GMR elements 11 and 12 There, _{X 2} is an element group consisting of X-axis GMR elements 13 and 14.
Since the sensitivity direction of these X-axis GMR elements 11 to 14 is the X-axis sensitivity direction F1 in FIG. 5, when a magnetic field is applied from the outside to the X-axis sensitivity direction F1, in the figure, H becomes a high potential, and from the outside When a magnetic field is applied in the direction opposite to the X-axis sensitivity direction F1, L in the figure becomes a high potential.

Figure 8 is a block diagram showing a bridge connection of the Y-axis magnetic sensor of the magnetic sensor 1 (Y-axis GMR elements 21 to 24), in FIG., _{Y 1} is a element group consisting of Y-axis GMR elements 21 and 22 Y ₂ is an element group composed of Y-axis GMR elements 23 and 24.
Since the sensitivity direction of these Y-axis GMR elements 21 to 24 is the Y-axis sensitivity direction F2 of FIG. 5, when a magnetic field is applied from the outside to the Y-axis sensitivity direction F2, in the figure, H becomes a high potential, and from the outside When a magnetic field is applied in the direction opposite to the Y-axis sensitivity direction F2, L in the figure becomes a high potential.

FIG. 9 is a diagram showing the magnetic characteristics of the X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24 of the magnetic sensor 1, and FIG. 10 shows conventional X-axis GMR elements 111 to 114 and Y-axis GMR. It is a figure which shows the magnetic characteristic of each of the elements 121-124.
In the figure, the solid line indicates the magnetic characteristic in the sensitivity direction of each GMR element, and the broken line indicates the magnetic characteristic in the insensitive direction of the same GMR element.

In the GMR element of the present embodiment, no hysteresis is observed in the loop in the sensitivity direction, and hysteresis is recognized in the loop in the insensitivity direction. However, this hysteresis is not at or near the magnetic field. The characteristics are improved.
On the other hand, in each conventional GMR element, hysteresis is observed in the loop in the insensitive direction. However, since this magnetic field is in the vicinity of zero, the strong magnetic field resistance is deteriorated.
Therefore, the GMR element of this embodiment has a strong magnetic field resistance compared to the conventional GMR element by setting the longitudinal direction of the magnetoresistive effect element 31 and the longitudinal direction of each of the permanent magnet films 32 and 32 to 45 °. It can be seen that is significantly improved.

  As described above, according to the magnetic sensor 1 of the present embodiment, the X-axis GMR elements 11 to 14 and the Y-axis GMR elements 21 to 24 are formed on the quartz substrate 2, and these X-axis GMR elements 11 to 14 and Since the angle between the magnetization direction of the pinned layer PD of each of the Y-axis GMR elements 21 to 24 and the magnetization direction of the free layer F is 45 °, even when a strong magnetic field is applied, The movement of the bridge offset can be suppressed, and the magnetic field resistance can be improved.

  In addition, according to the method for manufacturing the magnetic sensor 1 of the present embodiment, the permanent magnet pieces 45, so that the polarities of the adjacent permanent magnet pieces 45 are different from each other at the four corners of the quartz substrate 2 divided by the subsequent cutting step. 45 and so on, and a magnetic field that coincides with the major axis direction is applied to each film M. Therefore, even when a strong magnetic field is applied, the movement of the bridge offset can be suppressed, and the magnetic field resistance characteristics It is possible to easily manufacture the magnetic sensor 1 that can improve the above in a simple process.

  In the present embodiment, a plate corresponding to exactly the same through-hole that is not changed in shape, spacing, or position and having an alignment mark shifted by a half pitch is used. Another plate with a shifted pitch may be used. Moreover, you may use what formed both the alignment mark shifted by half pitch, and the conventional alignment mark.

Further, the magnet array is made of, for example, a nickel iron (Ni-Fe) alloy such as 42 alloy as shown in FIG. A metal plate 47 made of tungsten (W) or the like in which a plurality of through holes 43 corresponding to the outer shape of the permanent magnet piece 45 are formed is disposed on the substrate 46, and the substrate 46 and the metal plate 47 are bonded. Alternatively, the through-holes 43 each having a permanent magnet piece 45 attached may be used.
As shown in FIG. 11B, the substrate 46 and the metal plate 47 are fixed to the quartz glass 41 by using a plurality of fixtures 155 such as clips, as in the prior art.

  In this magnet array, nickel iron (Ni—Fe) alloy such as 42 alloy or tungsten (W) has a thermal expansion coefficient close to that of silicon (Si), so that even when thermal expansion occurs due to heating, the position shift is not caused. There is no risk of occurrence, and the accuracy of the array is improved. Further, since the metal plate 47 is used as it is as a part of the magnet array without being removed, the holding accuracy of the permanent magnet piece 45 is improved and the manufacturing is easy.

“Second Embodiment”
FIG. 12 is a plan view showing a magnetic sensor according to the second embodiment of the present invention. The magnetic sensor 50 according to this embodiment is different from the magnetic sensor 1 according to the first embodiment in that the length of the magnetoresistive effect element 31 is long. The axial direction is parallel to the adjacent sides of the quartz substrate 2.
That is, the magnetic sensor 50 includes a substantially square quartz substrate 2 having a predetermined thickness, and an X-axis GMR element 51 constituting an X-axis magnetic sensor formed on the quartz substrate 2 and detecting a magnetic field in the X-axis direction. To 54 and Y-axis GMR elements 61 to 64 that constitute a Y-axis magnetic sensor that is formed on the quartz substrate 2 and detects a magnetic field in the Y-axis direction orthogonal to the X-axis.

  The X-axis GMR elements 51 to 54 are arranged in pairs near the midpoint of each of the two sides orthogonal to the X-axis on the quartz substrate 2 so that the pair of elements are parallel to each other. Similarly, the Y-axis GMR elements 61 to 64 are arranged in pairs near the midpoint of each of the two sides orthogonal to the Y-axis on the quartz substrate 2 so that the pair of elements are parallel to each other.

  The X-axis GMR elements 51 to 54 and the Y-axis GMR elements 61 to 64 are composed of a magnetoresistive effect element 31 having a substantially parallelogram shape as a whole formed of a plurality of strip-shaped spin valve films arranged in parallel to each other, and the magnetic resistance effect element 31. The magnetoresistive element 31 includes permanent magnet films 32 and 32 made of a substantially square thin film of a hard ferromagnetic material such as CoCrPt having a high coercive force and a high squareness ratio. The resistive element 31 and the permanent magnet films 32 and 32 are arranged so that the longitudinal directions thereof coincide with each other.

The magnetoresistive effect element 31 is formed in parallel with the side of the quartz substrate 2 whose major axis direction is close. The permanent magnet films 32 and 32 are also formed so that the major axis directions thereof are parallel to the adjacent sides of the quartz substrate 2 and the distances from the sides are equal to each other.
The magnetization direction of the pinned layer of the magnetoresistive effect element 31 is a direction inclined by 45 ° with respect to the major axis, and the magnetization directions of the permanent magnet films 32 and 32 are directions along the major axis. The direction of magnetization of the pinned layer of the magnetoresistive effect element 31 and the direction of magnetization of the permanent magnet films 32 and 32 form an angle of 45 °.

  The structure of the spin valve film itself is exactly the same as that of the conventional spin valve films 131 of the X-axis GMR elements 111 to 114 and the Y-axis GMR elements 121 to 124, just like the magnetic sensor 1 of the first embodiment. Therefore, description of the details of the film structure is omitted here.

In these X-axis GMR elements 51 to 54 and Y-axis GMR elements 61 to 64, the major axis direction of the pinned layer PD of the magnetoresistive effect element 31 is connected to the major axis direction of the permanent magnet film 32. Yes.
In the pinned layer PD of the magnetoresistive effect element 31, the magnetization direction is inclined by 45 ° with respect to the major axis direction, so that the magnetization direction of the pinned layer PD of the magnetoresistive effect element 31 is permanent. The angle formed by the magnetization direction of the magnet film 32 is 45 °.

Next, a method for manufacturing the magnetic sensor 50 will be described.
In this embodiment, two types of magnet arrays are used.
Similar to the magnetic sensor 1 described above, the permanent magnet films 32 and 32 and spin valve films for forming individual GMR elements are formed on a rectangular quartz glass.

Next, as shown in FIG. 13, a rectangular first metal plate 67 having a plurality of openings formed in parallel so that the opening 43 having a rectangular opening forms 45 ° is prepared. The bar magnets 68, 68,... Made of rectangular parallelepiped permanent magnets whose cross-sectional shape is substantially the same as that of the through hole 43 are formed in the through holes 43 of the 67, and the upper end surface of each bar magnet 68 is the first metal plate 67. It is inserted so as to be parallel to the surface and so that the polarities of the adjacent bar magnets 68 are different.
Thereafter, the first metal plate 67 is removed. This produces a magnet array in which the bar magnets 68, 68,... Are arranged in parallel and the polarities of the adjacent bar magnets 68 are different.

Next, as in the first embodiment, a plate made of a first transparent quartz glass having substantially the same shape as the first metal plate 67 is prepared, and the above-described bar magnets 68, 68,. The upper end surfaces of the bar magnets 68, 68,... Of one magnet array are bonded to the lower surface of the first plate with an adhesive. At this time, the bar magnets 68, 68,... And the first plate are positioned using the alignment mark.
Next, the quartz substrate is disposed so as to be in contact with the upper surface of the first plate. The alignment between the quartz glass 41 and the first plate is performed by aligning the alignment marks with each other. Thereafter, the quartz glass 41 and the first plate are fixed using a plurality of fixtures such as clips.
Such a magnet array in which the bar magnets 68, 68,... Are arranged in parallel does not cause a deviation in the direction of the magnetic field even if the position and interval thereof are deviated. The accuracy is good.

  Also in this embodiment, a plurality of through holes corresponding to the outer shape of the bar magnet 68 are formed on a substrate made of, for example, a 42 alloy nickel iron (Ni—Fe) alloy, as in the first embodiment. A metal plate made of tungsten (W) or the like may be disposed, the substrate and the metal plate may be bonded, and a bar magnet 68 may be attached to each through hole.

As the magnet array, in addition to the magnet array described above, magnet arrays having various structures as described below may be used.
(1) Magnet array in which bar magnets having different polarities are alternately arranged As shown in FIG. 14A, a plurality of grooves 73 parallel to the surface (one main surface) 71 a of the Si substrate 71 using a dicing saw 72. Form. The widths of these grooves 73 are substantially the same as the widths of the bar magnets 68 to be mounted, and are also substantially the same as the widths of the dicing saw 72. Further, the interval between the grooves 73 is ½ of the length of the diagonal line of the quartz substrate 2 as in the magnet array described above.

Next, as shown in FIG. 14B, the bar magnets 68 are inserted into the grooves 73 so that the polarities of the adjacent bar magnets 68 and 68 are different. In this case, the polarities of the bar magnets 68, 68,... Are alternately arranged as N, S, N,... On the surface 71a side of the Si substrate 71, as shown in FIG.
In this manner, a magnet array in which bar magnets 68 having different polarities are alternately arranged on the Si substrate 71 can be manufactured.

  In this magnet array, the interval between the adjacent bar magnets 68, 68 is ½ of the diagonal length of the quartz substrate 2, and therefore when this is placed on the quartz glass 41, it is shown in FIG. As described above, when one bar magnet 68 is aligned on the diagonal line of one cell (the area to be the quartz substrate 2 divided in the subsequent process) 75, the bar magnets 68 and 68 adjacent thereto are symmetrical with respect to the diagonal line. It will be located at the corner of the cell 75 at the position.

(2) Magnet array in which bar magnets having the same polarity are arranged in parallel to each other. As shown in FIG. 17A, a dicing saw 72 is provided on the surface (one main surface) 77a of a 42 alloy (Ni—Fe alloy) substrate 77. A plurality of parallel grooves 73 are formed by using them. The width of these grooves 73 is substantially the same as the width of the bar magnet 68 to be mounted. The interval between these grooves 73 is the same as the length of the diagonal line of the quartz substrate 2.
Next, as shown in FIG. 17B, the bar magnets 68 are inserted into the grooves 73 so that the polarities of the adjacent bar magnets 68 and 68 are the same. In this case, the polarities of the bar magnets 68, 68,... Are alternately arranged on the surface 77a side of the 42 alloy substrate 77, for example, as N, N,.

Here, as shown in FIG. 18, since the 42 alloy between the adjacent bar magnets 68 and 68 has a polarity S opposite to that of N, the bar magnets 68, 68,. As shown, a bar magnet having a polarity different from N, S, N,... Along one direction on the surface 77a (the left-right direction in FIG. 18) appears to be ½ of the diagonal line of the quartz substrate 2. It becomes the same state as what is arrange | positioned in parallel by the space | interval of length.
In this manner, a magnet array in which bar magnets 68 having the same polarity are arranged in parallel on the 42 alloy substrate 77 can be produced.

In this magnet array, the interval between the adjacent bar magnets 68 and 68 is equal to the diagonal length of the quartz substrate 2, so that when this is placed on the quartz glass 41, as shown in FIG. When one bar magnet 68 is aligned with the diagonal line of one cell 75, the corners of the cell 75 located symmetrically across the diagonal line are aligned with the bar magnet 68 and the bar magnets 68, 68 adjacent thereto. And the line segments 76 and 76 that divide the interval into two. Since the positions of these line segments 76 and 76 are equivalent to a magnet (S pole) having a polarity different from that of the bar magnet 68, the S pole of the magnet is arranged at the corner of the cell 75.
When such a magnet array is used, the bar magnets 68 are attracted to each other and do not fall down or rotate, so that the bar magnets 68 that cannot be prevented by a thin metal plate can be fixed easily and accurately. it can.

Next, of the pinned layer of the magnetoresistive effect element 31, a regularizing heat treatment is performed on the pinning layer PN.
As shown in FIG. 20, the bar magnets 68, 68,... Are inclined on the quartz glass 41 by 45 ° with respect to one side so that the polarities of both ends of the adjacent bar magnets 68, 68 are different from each other. Place.
In this case, a magnetic field directed from one to the other is formed between the adjacent bar magnets 68, 68, but this magnetic field is inclined by 45 ° with respect to each side of the quartz substrate 2, so that A magnetic field in a direction inclined by 45 ° with respect to the major axis direction is applied to the region M of the valve film.

Thereafter, heat treatment is performed at 250 ° C. to 280 ° C. for 4 hours in a vacuum while the quartz glass 41 and the plate are fixed with a fixture.
Thereby, the ordering heat treatment of the pinning layer of the magnetoresistive effect element 31 of each of the X-axis GMR elements 51 to 54 and the Y-axis GMR elements 61 to 64 can be performed.
Thereafter, similarly to the first embodiment, patterning of the spin valve film is performed.
In this magnetic sensor 50, the X-axis sensitivity direction F1 and the Y-axis sensitivity direction F2 of the pinned layer P of the magnetoresistive effect element 31 are as shown in FIG.

Next, as shown in FIG. 22, the permanent magnet film 32 is magnetized using a magnet array having the same configuration as the magnet array used in the first embodiment.
Here, as in the first embodiment, the permanent magnet pieces 45, 45,... Are arranged at the four corners of the quartz substrate 2 divided by the subsequent cutting step so that the polarities of the adjacent permanent magnet pieces 45 are different from each other. Therefore, a magnetic field from one permanent magnet piece 45 (N pole) toward the other permanent magnet piece 45 (S pole) is formed. Since this magnetic field is parallel to each side of the quartz substrate 2, a magnetic field matching the major axis direction is applied to the permanent magnet film 32.

In this manner, the magnetic sensor 50 in which the free layer F of the pinned layer of the magnetoresistive effect element 31 is initialized and the permanent magnet film 32 is magnetized can be manufactured.
The bridge connection of the magnetic sensor 50 is exactly the same as in the first embodiment.
In this embodiment, the same effect as that of the first embodiment can be obtained.

“Third Embodiment”
In the second embodiment, the permanent magnet film 32 is magnetized using a magnet array having the same configuration as the magnet array used in the first embodiment. The magnet array used in the regularized heat treatment according to the embodiment can also be used as it is without changing its position.
In this magnetization, a magnetic field is formed along a diagonal line of the quartz substrate 2 divided in a later step and inclined at an angle of 45 ° with respect to one side of the quartz substrate 2. A magnetic field in a direction that forms an angle of 45 ° with the major axis is applied to the permanent magnet film 32 whose major axis is formed in parallel to each of the sides.

In this case, the end of the free layer F is initialized in the same direction as the magnetization of the permanent magnet film 32. In general, in the free layer F, the initialization direction is aligned in the longitudinal direction due to the shape anisotropy. Therefore, as a whole, the initial direction is the longitudinal direction of the GMR element, that is, the direction along one side of the quartz substrate 2. Will be converted.
In this way, a magnetic sensor in which the free layer F of the magnetoresistive element 31 is initialized and the permanent magnet film 32 is magnetized can be manufactured.
In the present embodiment, the sensitivity at the end of the free layer F is inferior to that of the magnetic sensor of the second embodiment. However, as in the first embodiment, the direction of the magnetic field is the same. The offset fluctuation is small.

“Fourth Embodiment”
FIG. 23 is a plan view showing a magnetic sensor according to a fourth embodiment of the present invention. The magnetic sensor 81 according to the present embodiment is different from the magnetic sensor 50 according to the second embodiment in that the magnetic sensor according to the second embodiment. In the sensor 50, the X-axis GMR elements 51 and 52 are arranged in parallel with each other in the vicinity of the central portion of one side on the negative direction of the X-axis on the quartz substrate 2, and the Y-axis GMR elements 63 and 64 are arranged on the quartz substrate 2. Whereas the magnetic sensor 81 according to the present embodiment is arranged so as to be parallel to each other in the vicinity of the central portion of one side of the Y-axis negative direction, the X-axis GMR elements 51 and 52 and the Y-axis GMR elements 63 and 64 have sensitivity. The X-axis GMR elements 51 and 52 and the Y-axis GMR elements 63 and 64 are arranged at the central portion on the quartz substrate 2 so as to be inclined by 45 ° with respect to one side of the quartz substrate 2 so as not to have them. is there.

When manufacturing this magnetic sensor 81, when performing the regularizing heat treatment of the pinning layer of the magnetoresistive effect element 31, the quartz glass 41 is heat-treated in a vacuum at 250 ° C. to 280 ° C. for 4 hours, and the X-axis GMR. A magnetic field may be applied in parallel to the elements 51 and 52 and the Y-axis GMR elements 63 and 64. That is, as shown in FIG. 24, it is desirable to apply a magnetic field having a uniform intensity along the X-axis GMR elements 51 and 52 and the Y-axis GMR elements 63 and 64 and from the lower left to the upper right in the drawing.
When magnetizing, the quartz glass and the plate are fixed as in the above-described embodiment.

  In this manner, the free layer F of the magnetoresistive effect element 31 of each of the X-axis GMR elements 51 to 54 and the Y-axis GMR elements 61 to 64 can be initialized and the permanent magnet film 32 can be magnetized. The magnetic sensor 71 in which the pinned layer PD and the permanent magnet film 32 of the effect element 31 are magnetized can be manufactured.

In this magnetic sensor 81, the X-axis sensitivity direction F1 and the Y-axis sensitivity direction F2 of the pinned layer P of the magnetoresistive effect element 31 excluding those arranged at the center are as shown in FIG.
The bridge connection of the magnetic sensor 81 is exactly the same as in the first embodiment.
In this embodiment, the same effect as that of the first embodiment can be obtained.

“Fifth Embodiment”
In the present embodiment, when the permanent magnet film 32 is magnetized, the magnet array is not used, and the fourth embodiment described above is applied except that a uniform magnetic field is applied in the same manner as the ordering heat treatment step. The form is exactly the same.
Here, the magnetization of the permanent magnet film 32 will be described.
Just like the ordering heat treatment step, as shown in FIG. 24, a magnetic field having a uniform intensity is applied from the lower left to the upper right.

  Looking at the X-axis GMR elements 51 and 52 and the Y-axis GMR elements 63 and 64 along the side of the quartz glass 41, an angle of 45 ° with respect to the one side from the diagonal line of the quartz substrate 2 divided by the subsequent cutting process. Therefore, a magnetic field in a direction that forms an angle of 45 ° with the major axis is applied to the permanent magnet film 32 whose major axis is formed in parallel with each side of the quartz substrate 2. It will be.

On the other hand, the end portion of the free layer F is initialized in the same direction as the magnetization direction of the permanent magnet film 32. However, the free layer F is aligned in the longitudinal direction due to the shape anisotropy, and as a whole the GMR element. Is initialized in the direction along the side of the quartz glass 41.
In the present embodiment, the sensitivity at the end of the free layer F is inferior to that of the magnetic sensor of the second embodiment. However, as in the first embodiment, the direction of the magnetic field is the same. The offset fluctuation is small.

Table 1 compares the characteristics of the magnetic sensor of the present invention (Examples 1 to 5) and the conventional magnetic sensor (conventional example).
Here, as Example 1, the magnetic sensor 1 of the first embodiment, as Example 2, the magnetic sensor 50 of the second embodiment, as Example 3, the magnetic sensor of the third embodiment, and as Example 4. The magnetic sensor 71 of the fourth embodiment was used as the fifth embodiment, and the magnetic sensor of the fifth embodiment was used as the fifth embodiment.

According to Table 1, it turned out that the magnetic sensor of Examples 1-5 is excellent in the strong magnetic field characteristic compared with the prior art example.
In Examples 1 to 5, the offset variation after 100 Oe exposure is small compared to the conventional example. This indicates “strong magnetic field resistance”.
In Examples 1 to 5, although the sensitivity is inferior to that of the conventional example in which the longitudinal direction of the GMR element is perpendicular to the magnetization direction in the ordered heat treatment, the magnetic field resistance is better.

Further, comparing Examples 1 to 5, Examples 1, 3, and 5 in which the magnetization direction of the permanent magnet film and the magnetization direction of the ordered heat treatment of the GMR element are the same are not the same. Compared to Examples 2 and 4, the magnetic field resistance is better.
On the other hand, in Examples 1, 3, and 5 in which the magnetization direction of the permanent magnet film and the longitudinal direction of the GMR element (longitudinal direction of the free layer) do not coincide with each other, the permanent magnet film is deposited at the end of the free layer. Since the magnetic direction is aligned, loss occurs and sensitivity is slightly reduced. However, the “magnetic field resistance characteristics” are the same because the magnetization direction of the permanent magnet film and the magnetization direction of the ordered heat treatment of the GMR element are the same. "Is good, the fluctuation ratio with respect to sensitivity is small.

It is a top view which shows the magnetic sensor of the 1st Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnetic sensor of the 1st Embodiment of this invention. It is a fragmentary top view which shows the metal plate used with the manufacturing method of the magnetic sensor of the 1st Embodiment of this invention. It is a fragmentary top view which shows the metal plate used with the manufacturing method of the conventional magnetic sensor. It is a top view which shows the sensitivity direction of the magnetic sensor of the 1st Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnetic sensor of the 1st Embodiment of this invention. It is a block diagram showing bridge connection of a magnetic sensor of a 1st embodiment of the present invention. It is a block diagram showing bridge connection of a magnetic sensor of a 1st embodiment of the present invention. It is a figure which shows the magnetic characteristic of the GMR element of the magnetic sensor of the 1st Embodiment of this invention. It is a figure which shows the magnetic characteristic of the GMR element of the conventional magnetic sensor. It is process drawing which shows the manufacturing method of the magnet array used with the manufacturing method of the magnetic sensor of the 1st Embodiment of this invention. It is a top view which shows the magnetic sensor of the 2nd Embodiment of this invention. It is a top view which shows the magnet array used with the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnet array of the modification used by the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a fragmentary perspective view which shows the state of the magnetic field of the magnet array of the modification used in the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a top view which shows the positional relationship of the magnet array and quartz substrate of the modification used with the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnet array of the other modification used with the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a fragmentary perspective view which shows the state of the magnetic field of the magnet array of the other modification used with the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a top view which shows the positional relationship of the magnet array of another modification used in the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention, and a quartz substrate. It is a top view which shows the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a top view which shows the sensitivity direction of the magnetic sensor of the 2nd Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnetic sensor of the 2nd Embodiment of this invention. It is a top view which shows the magnetic sensor of the 4th Embodiment of this invention. It is process drawing which shows the manufacturing method of the magnetic sensor of the 4th Embodiment of this invention. It is a top view which shows the sensitivity direction of the magnetic sensor of the 4th Embodiment of this invention. It is a top view which shows the biaxial magnetic sensor using the GMR element which the present inventors have already proposed. It is a top view which shows the GMR element of a biaxial magnetic sensor. It is sectional drawing which follows the AA line of FIG. It is sectional drawing which shows the structure of the spin-valve film | membrane of a GMR element. It is a figure which shows the magnetic characteristic of a GMR element. It is a block diagram which shows the bridge connection of a X-axis magnetic sensor. It is a figure which shows the magnetic characteristic of an X-axis magnetic sensor. It is a block diagram which shows the bridge connection of a Y-axis magnetic sensor. It is a figure which shows the magnetic characteristic of a Y-axis magnetic sensor. It is a top view which shows the state which formed the GMR element film | membrane on the quartz glass used for the manufacturing method of a biaxial magnetic sensor. It is a top view which shows the preparation process of the magnet array used for the manufacturing method of a biaxial magnetic sensor. It is sectional drawing which follows the BB line of FIG. It is a top view which shows the transparent quartz glass plate used in the manufacturing method of a biaxial magnetic sensor. It is sectional drawing which shows the state which adhered the permanent magnet of the magnet array to quartz glass. It is sectional drawing which shows the state which fixed the quartz glass and the plate with the fixing tool. It is a schematic diagram which shows the direction of the magnetic field of the permanent magnet of a magnet array. It is a top view which shows the method of magnetizing the magnetic thin film of 1 process of the manufacturing method of a biaxial magnetic sensor.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Magnetic sensor, 2 ... Quartz substrate, 11-14 ... X-axis GMR element, 21-24 ... Y-axis GMR element, 31 ... Magnetoresistive element, 32 ... Permanent magnet film, 41 ... Quartz glass, 43 ... Through-hole 44 ... Metal plate, 45 ... Permanent magnet piece, 50 ... Magnetic sensor, 51-54 ... X-axis GMR element, 61-64 ... Y-axis GMR element, 67 ... Metal plate, 68 ... Bar magnet, 71 ... Si substrate, 73 ... groove, 75 ... cell, 77 ... 42 alloy substrate, 81 ... magnetic sensor.

Claims (1)

In a magnetic sensor in which at least one magnetoresistive effect element is formed on a substrate and permanent magnet films are respectively connected to both ends of the magnetoresistive effect element, and the magnitude of the magnetic field is detected by the magnetoresistive effect element.
The direction of the pinned magnetization of the pinned layer of the magnetoresistive element and the longitudinal direction of the magnetoresistive element form an angle of 45 °, and the direction of the pinned magnetization of the pinned layer is A magnetic sensor having the same direction of magnetization after magnetization of a permanent magnet film.

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