JP3835445B2 - Magnetic sensor - Google Patents

Description

  The present invention relates to a magnetic sensor using a magnetoresistive effect element including a pinned layer and a free layer, and in particular, two or more magnetoresistive effect elements whose magnetization directions of the pinned layer intersect each other are arranged on a single chip. The present invention relates to a magnetic sensor.

Conventionally, giant magnetoresistive elements (GMR elements), magnetic tunnel effect elements (TMR elements), and the like are known as elements that can be used in magnetic sensors. These magnetoresistive elements include a pinned layer whose magnetization direction is pinned (fixed) in a predetermined direction, and a free layer whose magnetization direction changes according to an external magnetic field. It exhibits a resistance value corresponding to the relative relationship between the direction and the magnetization direction of the free layer (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-70325

  However, it is difficult to form two or more magnetoresistive elements in which the magnetization directions of the pinned layer intersect each other on a small single chip, and no such single chip has been proposed. A magnetic sensor composed of a single chip using a magnetoresistive element has a problem that its application range cannot be widened due to the restriction of the magnetization direction of the pinned layer.

  A feature of the present invention is a magnetic sensor including a magnetoresistive effect element that includes a pinned layer and a free layer, and whose resistance value changes according to a relative angle formed by the magnetization direction of the pinned layer and the magnetization direction of the free layer. A plurality of the magnetoresistive effect elements are provided on a single chip, and the magnetization directions of the pinned layers of at least two of the plurality of magnetoresistive effect elements intersect each other. There is to be done.

  More specifically, according to the present invention,
  A magnetic sensor comprising a giant magnetoresistive element including a pinned layer and a free layer, the resistance value of which changes according to the relative angle between the direction of magnetization of the pinned layer and the direction of magnetization of the free layer,
  A single chip having a substantially square shape, which is formed by cutting one substrate and has sides along the X axis and the Y axis perpendicular to each other in plan view,
  A total of eight giant magnetoresistive elements formed on the chip;
  With
  The eight giant magnetoresistive elements are:
  A first X-axis GMR element formed in the vicinity of the end of the X-axis negative direction below the center of the chip in the Y-axis direction and in the first direction along the X-axis.
  A second X-axis GMR element formed in the vicinity of an end in the negative X-axis direction at a position approximately above the center in the Y-axis direction of the chip, wherein the pinned layer has a pinned magnetization direction in the first direction;
  A third X-axis GMR formed in the vicinity of the positive end of the X-axis in the upper part of the Y-axis direction of the chip and in the vicinity of the positive end of the X-axis. Elements,
  The fourth X-axis GMR is formed in the vicinity of the positive end of the X-axis in the lower part of the Y-axis direction of the chip and in the vicinity of the positive end of the X-axis, and the pinned magnetization direction is opposite to the first direction along the X-axis Elements,
  A first Y-axis GMR element formed in the vicinity of the Y-axis positive direction end on the left side of the center of the chip in the X-axis direction and in the second direction along the Y-axis.
  A second Y-axis GMR element formed in the vicinity of the Y-axis positive direction end on the right side of the center in the X-axis direction of the chip, and the pinned magnetization direction of the pinned layer in the second direction;
  A third Y-axis formed in the vicinity of the Y-axis negative direction end on the right side of the center of the chip in the X-axis direction and in the direction opposite to the second direction along the Y-axis. A GMR element;
  A fourth Y-axis formed in the vicinity of the Y-axis negative direction end on the left side of the center of the chip in the X-axis direction and in the direction opposite to the second direction along the Y-axis. A GMR element;
  Consists of
  The first to fourth X-axis GMR elements constitute an X-axis magnetic sensor that exhibits an output voltage that changes substantially in proportion to the external magnetic field that changes along the X-axis by being fully bridged,
  The first to fourth Y-axis GMR elements constitute a Y-axis magnetic sensor that exhibits an output voltage that changes substantially in proportion to the external magnetic field that changes along the Y-axis by being fully bridged. Yes,
  A magnetic sensor is provided.

  As described above, according to the magnetic sensor of the present invention, since the magnetoresistive effect elements having the magnetization directions of the pinned layers intersecting each other are formed on the same chip, a magnetic sensor having a small size and a wide application range is provided. The

  In this case, a coil for applying a magnetic field to the plurality of magnetoresistive elements may be embedded in the single chip. In addition, wiring for connecting the plurality of magnetoresistive elements to the single chip may be formed. Further, a plurality of pads may be provided on the single chip, and wirings for connecting the plurality of magnetoresistive elements and the plurality of pads may be formed on the single chip.

  Embodiments of a magnetic sensor according to the present invention will be described below with reference to the drawings. As shown in FIG. 1 which is a plan view, the magnetic sensor according to the first embodiment includes a substantially square substrate 10 made of, for example, SiO 2 / Si, glass, or quartz, and two magnetic tunnel effect elements (groups) 11. , 21, a bias magnetic field coil 30, and a plurality of electrode pads 40 a to 40 f. The magnetic tunnel effect element (group) 11, 21 and the bias magnetic field coil 30 are connected to electrode pads 40a, 40b, 40c, 40d, and 40e, 40f, respectively. Since the magnetic tunnel effect element (group) 11 and the magnetic tunnel effect element (group) 21 are identical in structure, the magnetic tunnel effect element (group) 11 will be described below as a representative example. ) A description of 21 is omitted.

  As shown in FIG. 2 which is an enlarged plan view, the magnetic tunnel effect element (group) 11 is composed of a plurality (20 in this example) of magnetic tunnel effect elements connected in series. Each magnetic tunnel effect element includes a plurality of lower electrodes 12 having a rectangular planar shape on a substrate 10 as shown in FIG. 3 which is a partial cross-sectional view taken along the plane 1-1 of FIG. Yes. The lower electrodes 12 are arranged in a row at predetermined intervals in the horizontal direction, and are formed to a thickness of about 30 nm from Ta (Cr, Ti may be used) which is a conductive nonmagnetic metal material. On each lower electrode 12, an antiferromagnetic film 13 made of PtMn having a film thickness of about 30 nm is laminated, which is formed in the same plane shape as the lower electrode 12.

  On each antiferromagnetic film 13, a pair of ferromagnetic films 14, 14 made of NiFe having a thickness of about 20 nm are stacked with a gap therebetween. The ferromagnetic films 14 and 14 have a rectangular shape in plan view, are arranged so that their long sides face each other in parallel, and a pinned layer whose magnetization direction is pinned by the antiferromagnetic film 13 is formed. It is configured and is magnetized in the direction of the arrow (rightward) in FIG. 4 which is a partially enlarged plan view. The antiferromagnetic film 13 and the ferromagnetic film (pinned layer) 14 constitute a fixed magnetic layer in which the magnetization direction is substantially fixed (having a fixed magnetization axis).

  An insulating layer 15 having the same planar shape as the ferromagnetic film 14 is formed on each ferromagnetic film 14. This insulating layer 15 is made of Al2O3 (Al-O), which is an insulating material, and is formed to have a thickness of about 1 nm.

  On the insulating layer 15, a ferromagnetic film 16 made of NiFe having the same planar shape as the insulating layer 15 and having a thickness of about 80 nm is formed. The ferromagnetic film 16 constitutes a free layer (free magnetic layer) whose magnetization direction changes according to the direction of the external magnetic field, and a magnetic tunnel junction together with the pinned layer made of the ferromagnetic film 14 and the insulating layer 15. Forming a structure. That is, the antiferromagnetic film 13, the ferromagnetic film 14, the insulating layer 15, and the ferromagnetic film 16 constitute one magnetic tunnel effect element (excluding electrodes and the like).

  On each ferromagnetic film 16, a dummy film 17 having the same planar shape as each ferromagnetic film 16 is formed. The dummy film 17 is made of a conductive nonmagnetic metal material made of a Ta film having a thickness of about 40 nm.

  A plurality of lower electrodes 12 and antiferromagnetic films 13 are respectively formed in regions covering the substrate 10, the lower electrode 12, the antiferromagnetic film 13, the ferromagnetic film 14, the insulating layer 15, the ferromagnetic film 16, and the dummy film 17. In addition to insulating and isolating, an interlayer insulating layer 18 for isolating and isolating the pair of ferromagnetic films 14, insulating layer 15, ferromagnetic film 16 and dummy film 17 provided on each antiferromagnetic film 13 is provided. . The interlayer insulating layer 18 is made of SiO2, and its film thickness is about 250 nm.

  In the interlayer insulating layer 18, contact holes 18a are formed on the dummy films 17, respectively. The contact hole 18a is buried and, for example, a film thickness of 300 nm is formed so as to electrically connect each of the pair of dummy films 17 and 17 provided on the different lower electrodes 12 (and the antiferromagnetic film 13). Upper electrodes 19 and 19 made of Al are respectively formed. As described above, the lower electrode 12 and the antiferromagnetic film 13 and the upper electrode 19 make the pair of adjacent ferromagnetic films 16 and 16 (the dummy films 17 and 17) and the antiferromagnetic films of the magnetic tunnel junction structure. Magnetic tunnel effect elements (group) in which the magnetization directions of the pinned layer are the same and the plurality of magnetic tunnel junction structures are connected in series by electrically connecting the films 13 and 13 alternately and sequentially. 11 is formed. A protective film made of SiO and SiN (not shown) is formed on the upper electrodes 19 and 19.

  The coil 30 is for applying an AC bias magnetic field to the magnetic tunnel effect element (group) 11, 21, and the magnetic tunnel effect element (group) 11, 21 is provided below the magnetic tunnel effect element (group) 21, 21. ) It is embedded in the upper part of the substrate 10 so as to extend in a direction parallel to the magnetization direction of the pinned layers 11 and 21.

  Next, a method for manufacturing the magnetic tunnel effect element will be described with reference to FIGS. 5 to 12 and FIGS. 14 to 17 show a magnetic tunnel effect element group in which four magnetic tunnel effect elements are connected in series for the sake of explanation. In these drawings, the coil 30 is omitted.

  First, as shown in FIG. 5, a film made of Ta constituting the lower electrode 12 is formed on a substrate 10 (in this stage, a single substrate from which a plurality of magnetic sensors are obtained by later dicing). A film made of PtMn and a film made of NiFe for forming an antiferromagnetic film 13 and a ferromagnetic film (pinned layer) 14 of a fixed magnetization layer by sputtering to a film thickness of about 30 nm each have a film thickness of 30 nm. And it forms by sputtering so that it may become 20 nm. Here, the lower electrode 12, the PtMn film serving as the antiferromagnetic film 13, and the FeNi film serving as the ferromagnetic film 14 are referred to as a lower magnetic layer SJ.

  Thereafter, Al is laminated by 1 nm, and this is oxidized with oxygen gas to form a film made of Al2O3 (Al-O) to be the insulating layer 15. Next, a film made of NiFe constituting the ferromagnetic film 16 of the free layer is formed by sputtering, for example, to a film thickness of 80 nm, and a film made of Ta constituting the dummy film 17 is formed thereon with a film thickness of 40 nm. It forms so that it may become. Here, the ferromagnetic film 16 and the dummy film 17 are referred to as the upper magnetic layer UJ. Next, the upper magnetic layer UJ is processed and separated as shown in FIG. 6 by ion milling or the like, and the lower magnetic layer SJ is processed and separated as shown in FIG.

  Next, as shown in FIG. 8, a film made of SiO2 constituting the interlayer insulating layer 18 is formed by sputtering so that the film thickness is 250 nm on the element, and a film made of Cr is formed thereon as a plating base film. And a film made of NiFe are formed by sputtering so that the film thicknesses become 100 nm and 50 nm, respectively. Next, a resist 51 is applied as shown in FIG. The resist 51 is patterned into a predetermined shape so as not to cover a portion to be plated later.

  Next, as shown in FIG. 10, NiCo is plated as a magnetic layer for applying a magnetic field. The thickness of this NiCо is, for example, 10 μm. Then, after removing the resist as shown in FIG. 11, NiFe formed as a plating base film is removed by milling (Ar milling) on the entire surface as shown in FIG.

  FIG. 13 is a plan view of the wafer in such a state. In FIG. 13, a reference numeral 10 is attached for convenience to each of the substrates divided by subsequent dicing. As shown in FIG. 13, the magnetic layer for applying a magnetic field (NiCо) has a substantially square shape by the patterning of the previous resist, and the center of the substrate 10 is divided into four after the adjacent four. A lower magnetic layer formed so as to be on the center and excluding the portion directly above the magnetic tunnel effect element (group) 11 and 21 in the vertical and horizontal directions (that is, including a magnetic layer to be a pinned layer in plan view) SJ (magnetic layer serving as a pinned layer) is disposed (so as to sandwich a layer serving as the magnetic tunnel effect element (group) 11 and 21). In this state, a magnetic field having a strength of about 1000 (Oe) is applied in a direction parallel to the square diagonal line formed by each magnetic field application magnetic layer, and the magnetic field application magnetic layer is oriented in the direction indicated by arrow A in FIG. Is magnetized (magnetized).

  Next, the magnetic field is removed. At this time, due to the residual magnetization of the magnetic field application magnetic layer, as indicated by the arrow B in FIG. 13, the magnetic fields from the upper side of each magnetic field application magnetic layer toward the lower side of the adjacent magnetic field application magnetic layer A magnetic field is generated from the right side of the magnetic field application magnetic layer toward the left side of the adjacent magnetic field application magnetic layer. For this reason, a magnetic field parallel to the longitudinal direction of the portions to be the magnetic tunnel effect elements (groups) 11 and 21 is applied. Then, in order to alloy the antiferromagnetic film 13 made of PtMn and provide an exchange coupling magnetic field Hex, a high temperature annealing process is performed in which the wafer is placed in a high temperature environment. As a result, the magnetic tunnel effect elements (groups) 11 and 21 formed on the same substrate 10 have pinned layers magnetized (pinned) in different directions (in this case, directions orthogonal to each other). To have. That is, each magnetic tunnel effect element (group) 11 and 21 has a magnetization fixed axis in the direction indicated by the arrow in FIG.

  Next, as shown in FIG. 14, NiCo as a plating film and sputtered NiFe (of the plating base film) are removed by acid, and Cr is removed by milling as shown in FIG. Thereafter, contact holes 18a are formed in the interlayer insulating layer 18 as shown in FIG. 16, and an Al film is formed by sputtering so as to have a film thickness of 300 nm as shown in FIG. The upper electrode 19 is formed by processing.

  Then, the electrode pads 40 a to 40 f shown in FIG. 1 are formed on the substrate 10, and the electrode pads 40 a to 40 f are connected to the magnetic tunnel effect elements (groups) 11 and 21 and the coil 30, respectively. Finally, a film made of SiO (not shown) having a thickness of 150 nm and a film (not shown) made of SiN having a thickness of 1000 nm are formed as a protective film (passivation film) by CVD. Thereafter, a part of the protective film is opened by milling, RIE, or etching using a resist mask to expose the electrode pads 40a to 40f. Next, the substrate is ground (thinned and thinned), separated into individual magnetic sensors by dicing, and finally packaged.

  With respect to the magnetic tunnel effect element (group) 11 shown in FIG. 1 manufactured in this way, the size changes along the X-axis direction and the Y-axis direction orthogonal to the X-axis direction in FIG. An external magnetic field was applied, and the resistance change rate MR (MR ratio) at that time was measured. The results are shown in FIGS. As is apparent from FIGS. 18 and 19, the MR ratio of the magnetic tunnel effect element (group) 11 changed more greatly with respect to the external magnetic field changing in the X-axis direction than with respect to the external magnetic field changing in the Y-axis direction. . This confirmed that the magnetization direction of the pinned layer of the magnetic tunnel effect element (group) 11 was parallel to the X axis.

  Similarly, an external magnetic field whose magnitude varies along the X-axis direction and the Y-axis direction is applied to the magnetic tunnel effect element (group) 21 shown in FIG. 1, and the resistance change rate MR at that time is given. (MR ratio) was measured. The results are shown in FIGS. As is apparent from FIGS. 20 and 21, the MR ratio of the magnetic tunnel effect element (group) 21 changed more greatly with respect to the external magnetic field changing in the Y-axis direction than with respect to the external magnetic field changing in the X-axis direction. . This confirmed that the magnetization direction of the pinned layer of the magnetic tunnel effect element (group) 21 was parallel to the Y axis. That is, this magnetic sensor has two magnetic tunnel effect elements (magnetoresistance effect elements) having pinned layers pinned so that the directions of magnetization are different from each other on the same substrate 10 (so that the directions of magnetization intersect each other). It was confirmed that

  Next, a magnetic sensor according to the second embodiment will be described. In the second embodiment, the fixed magnetization layer of the first embodiment is composed of PtMn and NiFe, whereas the fixed magnetization of the second embodiment is described. It differs from the first embodiment only in that the layer is composed of a film made of MnRh having a thickness of 30 nm and a film made of NiFe (pinned layer) having a thickness of 40 nm. On the other hand, the manufacturing method of the second embodiment is slightly different from that of the first embodiment due to the difference in the material of the fixed magnetic layer, and will be described below.

  That is, in the second embodiment, as shown in FIG. 22, a film made of Ta having a film thickness of 30 nm, a film made of MnRh having a film thickness of 30 nm, and a film thickness of 40 nm are formed on the substrate 10. A film made of NiFe is formed by sputtering to form the lower magnetic layer SJ. Next, 1 nm of Al is deposited and oxidized to form an insulating layer 15. A film made of NiFe having a thickness of 40 nm and a film made of Ta having a thickness of 40 nm are formed thereon to form the upper magnetic layer UJ.

  Next, the upper magnetic layer UJ is processed and separated as shown in FIG. 23, and the lower magnetic layer SJ is processed and separated as shown in FIG. Next, as shown in FIG. 25, SiO2 is sputtered to a thickness of 250 nm to form an interlayer insulating layer 18, and subsequently, contact holes are formed in the interlayer insulating layer 18 as shown in FIG. 18a is formed. Next, as shown in FIG. 27, Al is sputtered to a film thickness of 300 nm, and this is processed into a wiring shape to form the upper electrode 19. Then, as shown in FIG. 28, a protective film 20 made of SiO and SiN is formed by CVD.

  Next, as shown in FIG. 29, a film made of Cr and a film made of NiFe are formed by sputtering so that the film thicknesses become 100 nm and 50 nm, respectively, as the plating base film, and subsequently, as shown in FIG. A resist 51 is applied to the substrate. The resist 51 is patterned into a predetermined shape so as not to cover a portion to be plated later.

  Next, as shown in FIG. 31, NiCo is plated as a magnetic layer for applying a magnetic field. The thickness of this NiCо is, for example, 10 μm. Then, after removing the resist as shown in FIG. 32, NiFe formed as a plating base film is removed by milling (Ar milling) on the entire surface as shown in FIG. At this time, since the state shown in FIG. 13 is obtained, a magnetic field having a strength of about 1000 (Oe) is applied in a direction parallel to the square diagonal line formed by each magnetic field application magnetic layer, and the magnetic field application magnetic layer is Magnetization (magnetization) is performed in the direction indicated by the arrow A in FIG. 13, and then the magnetic field is removed.

  At this time, a magnetic field parallel to the longitudinal direction of the part is applied to the part to be the magnetic tunnel effect element (group) 11 ′ and 21 ′ later due to the residual magnetization of NiCо. Then, a high temperature annealing process is performed in which the wafer is placed in a high temperature environment. As a result, the magnetic tunnel effect elements (groups) 11 ′ and 21 ′ formed on the same substrate 10 ′ are magnetized (pinned) in different directions (in this case, directions orthogonal to each other). Will have a layer. After the high temperature annealing process is completed, the plating film NiCо and the NiFe of the plating base film are removed by acid as shown in FIG. 34, and the plating base film Cr is removed by milling as shown in FIG. Thereafter, the same processing as in the first embodiment is performed.

  The magnetic tunnel effect element (group) 11 ′ shown in FIG. 1 manufactured in this way is given an external magnetic field whose magnitude varies along the X-axis direction and the Y-axis direction. Resistance change rate MR (MR ratio) was measured. The results are shown in FIGS. 36 and 37. As is apparent from FIGS. 36 and 37, the MR ratio of the magnetic tunnel effect element (group) 11 ′ changes more greatly with respect to the external magnetic field changing in the X-axis direction than with respect to the external magnetic field changing in the Y-axis direction. did. This confirmed that the magnetization direction of the pinned layer of the magnetic tunnel effect element (group) 11 ′ was parallel to the X axis.

  Similarly, an external magnetic field whose magnitude varies along the X-axis direction and the Y-axis direction is applied to the magnetic tunnel effect element (group) 21 'shown in FIG. 1, and the resistance change rate at that time MR (MR ratio) was measured. The results are shown in FIGS. 38 and 39. As is apparent from FIGS. 38 and 39, the MR ratio of the magnetic tunnel effect element (group) 21 ′ changes more greatly with respect to the external magnetic field changing in the Y-axis direction than with respect to the external magnetic field changing in the X-axis direction. did. This confirmed that the magnetization direction of the pinned layer of the magnetic tunnel effect element (group) 21 ′ was parallel to the Y axis. That is, the magnetic sensor according to the second embodiment has two magnetic tunnel effect elements (magnetoresistance effect elements) each having a pinned layer pinned on the same substrate 10 'so that the directions of magnetization intersect (different). It was confirmed that

  As described above, in the magnetic sensors of the first and second embodiments, the magnetization directions of the pinned layers intersect each other (the angles formed by the magnetization directions of at least two pinned layers are other than 0 ° and 180 °). The magnetic tunnel effect element (which is an angle) is provided on the same substrate (on a single chip). For this reason, it can be used as a small magnetic sensor (for example, a geomagnetic sensor) that needs to detect magnetic fields in different directions. Moreover, according to the manufacturing method of each said embodiment, such a sensor can be manufactured easily.

  In the first embodiment, PtMn is used for the pinned layer of the pinned magnetic layer. However, since PtMn needs to pin the pinned layer at the first high temperature, such as CVD for protective film formation. High-temperature annealing is performed at a stage prior to high-temperature treatment. In contrast, in the second embodiment, MnRh is used for the pinned layer of the pinned magnetic layer, and the film quality of MnRh deteriorates if there is another high-temperature treatment after the high-temperature annealing treatment. Therefore, in the second embodiment, the high temperature annealing treatment is performed after the high temperature treatment such as CVD for forming the protective film.

  Moreover, according to the manufacturing method of the said 1st, 2nd embodiment, the magnetic tunnel effect element (group) which shows an even function characteristic with respect to the external magnetic field which it is going to detect can be obtained. That is, when the magnetic tunnel effect element group 11, 21, 11 ', 21' is given a magnetic field whose magnitude changes in the direction orthogonal to the magnetization direction of the pinned layer, the magnetization of the pinned layer is as shown in FIG. It changes smoothly as shown by the line LP. On the other hand, the free layer of these elements reacts sensitively to the direction of the external magnetic field due to the shape anisotropy, and when the magnitude of the external magnetic field is in the vicinity of “0” as shown by the line LF in FIG. To change. As a result, the relative angle between the magnetization direction of the pinned layer and the magnetization direction of the free layer becomes maximum (approximately 90 °) when the external magnetic field is “0”, and decreases as the magnitude (absolute value) of the external magnetic field increases. To do. This can be confirmed from FIG. 19, FIG. 20, FIG. 37, and FIG.

  Furthermore, as is apparent from FIG. 13, when the plating film (NiCо), which is the magnetic field application magnetic layer, is magnetized in a fixed direction indicated by the arrow A in FIG. The direction of the magnetic field generated between the plating films is different from the magnetization direction of the plating film, and is perpendicular to the end face of the plating film M as indicated by an arrow B in the figure. Therefore, for example, if the end face shape of the plating film M is designed as shown in FIG. 41 and the plating film is magnetized in the direction of the arrow C, a desired direction (in the direction of the arrow D is indicated) at an appropriate location on the wafer. A magnetic tunnel effect element having a fixed magnetization axis in a desired direction on a single substrate (the direction of magnetization of the pinned layer on a single chip). Magnetic tunnel effect elements TMR1 and TMR2 crossing each other can be manufactured.

  Next, the magnetic sensor according to the third embodiment of the present invention will be described. The magnetic sensor of the first and second embodiments is composed of a TMR element, whereas the magnetic sensor of the third embodiment is a GMR. It is comprised by the element. The magnetic sensor also includes an X-axis magnetic sensor that detects a magnetic field in the X-axis direction, and a Y-axis magnetic sensor that detects a magnetic field in the Y-axis direction orthogonal to the X-axis.

  More specifically, as shown in FIG. 42, the magnetic sensor 60 has a rectangular shape (substantially square shape) having sides along the X axis and the Y axis that are orthogonal to each other in a plan view. A single chip (same substrate) 60a made of quartz glass having a small thickness in the Z-axis direction orthogonal to the X-axis and the Y-axis, and a total of eight GMR elements 61 to 61 formed on the chip 60a. 64, 71 to 74, a total of eight pads 65 to 68 and 75 to 78 formed on the chip 60a, and a connection line for connecting each pad to each element.

  The first X-axis GMR element 61 is formed in the vicinity of the end in the X-axis negative direction below the center of the chip 60a in the Y-axis direction, and as shown by the arrow in FIG. 42, the pinned layer pinned magnetization. Is in the negative X-axis direction. The second X-axis GMR element 62 is formed in the vicinity of the end in the X-axis negative direction above the center in the Y-axis direction of the chip 60a, and as shown by the arrow in FIG. 42, the pinned layer pinned magnetization Is in the negative X-axis direction. The third X-axis GMR element 63 is formed in the vicinity of the end in the X-axis positive direction above the center of the chip 60a in the Y-axis direction, and as shown by the arrow in FIG. 42, the pinned layer pinned magnetization. Is in the positive direction of the X axis. The fourth X-axis GMR element 64 is formed in the vicinity of the end in the X-axis positive direction below the center of the chip 60a in the Y-axis direction, and as shown by the arrow in FIG. 42, the pinned layer pinned magnetization. Is in the positive direction of the X axis.

  The first Y-axis GMR element 71 is formed in the vicinity of the Y-axis positive direction end on the left side of the center portion of the chip 60a in the X-axis direction and pinned in the pinned layer as indicated by the arrow in FIG. The direction of magnetization is the Y axis positive direction. The second Y-axis GMR element 72 is formed in the vicinity of the Y-axis positive direction end on the right side of the center of the chip 60a in the X-axis direction and pinned in the pinned layer as indicated by the arrow in FIG. The direction of magnetization is the Y axis positive direction. The third Y-axis GMR element 73 is formed in the vicinity of the Y-axis negative direction end on the right side of the center of the chip 60a in the X-axis direction and pinned on the pinned layer as indicated by the arrow in FIG. The direction of magnetization is the negative Y-axis direction. The fourth Y-axis GMR element 74 is formed in the vicinity of the Y-axis negative direction end on the left side in the approximate center of the X-axis direction of the chip 60a, and pinned in the pinned layer as indicated by the arrow in FIG. The direction of magnetization is the negative Y-axis direction.

  The GMR elements 61 to 64 and 71 to 74 have substantially the same structure except that the arrangement in the chip 60a (the pinned magnetization direction of the pinned layer with respect to the chip 60a) is different. Accordingly, the structure of the first X-axis GMR element 61 will be described below as a representative example.

  The first X-axis GMR element 61 is as shown in FIG. 43, which is a plan view, and FIG. 44, which is a schematic cross-sectional view of the first X-axis GMR element 61 taken along the plane 2-2 in FIG. In addition, a plurality of narrow strip portions 61a... 61a made of a spin valve film SV and having a longitudinal direction in the Y-axis direction, and a hard strong material such as CoCrPt formed below both ends of the narrow strip portions 61a in the Y-axis direction. Bias magnet films (hard ferromagnetic thin film layers) 61b... 61b made of a magnetic material having a high coercive force and a high squareness ratio are provided. Each narrow strip portion 61a ... 61a extends in the X-axis direction on the upper surface of each bias magnet film 61b and is joined to the adjacent narrow strip portion 61a.

  As shown in FIG. 45, the spin valve film SV of the first X-axis GMR element 61 has a free layer (free layer, free magnetic layer) F stacked in order on a chip 60a as a substrate, and a film thickness. Is a conductive spacer layer S made of Cu having a thickness of 2.4 nm (24 mm), a pinned layer (fixed layer, fixed magnetic layer) P, and titanium (Ti) or tantalum (Ta) having a thickness of 2.5 nm (25 mm). The capping layer C is made of

  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 61-2 having a thickness of 3.3 nm (33 Å) formed on the layer 61-1 and the about 1-3 nm (10 to 30 Å) formed on the NiFe magnetic layer 61-2 The CoFe layer 61-3 has a thickness. The CoZrNb amorphous magnetic layer 61-1 and the NiFe magnetic layer 61-2 constitute a soft ferromagnetic thin film layer. The CoFe layer 61-3 prevents diffusion of Ni in the NiFe layer 61-2 and Cu61-4 in the spacer layer S. The above-described bias magnet films 61b... 61b maintain a uniaxial anisotropy of the free layer F so that the bias magnetic field in the Y-axis direction (the left-right direction indicated by the arrow in FIG. 43) with respect to the free layer F. Is given.

  The pinned layer P is composed of a CoFe magnetic layer 61-5 with a thickness of 2.2 nm (22 Å) and an antiferromagnetic film 61-6 with a thickness of 24 nm (240 Å) formed from a PtMn alloy containing 45 to 55 mol% of Pt. Are superimposed. The CoFe magnetic layer 61-5 is back-coupled to the magnetized (magnetized) antiferromagnetic film 61-6 in an exchange coupling manner so that the direction of magnetization (magnetization vector) is pinned (fixed) in the negative X-axis direction. This constitutes a pinned layer.

  As shown by the solid line in FIG. 46, the first X-axis GMR element 61 configured in this manner is substantially resistant to the same external magnetic field in the range of −Hc to + Hc with respect to the external magnetic field changing along the X-axis. It exhibits a resistance value that varies in proportion, and exhibits a substantially constant resistance value for an external magnetic field that varies along the Y axis, as indicated by the broken line in FIG.

  As shown in an equivalent circuit in FIG. 47, the X-axis magnetic sensor is configured by first to fourth X-axis GMR elements 61 to 64 being full-bridge connected. In FIG. 47, the arrows indicate the directions of pinned magnetization of the pinned layers of the GMR elements 61 to 64. In such a configuration, the pad 67 and the pad 68 are respectively connected to a positive electrode and a negative electrode of a constant voltage source (not shown), and have a potential Vxin + (5 (V) in this example) and a potential Vxin− (0 (V in this example)). )). Then, the potentials of the pads 65 and 66 are taken out as the potential Vxout + and the potential Vxout-, respectively, and the potential difference (Vxout + −Vxout−) is taken out as the sensor output Vxout. As a result, the X-axis magnetic sensor changes substantially in proportion to the external magnetic field in the range of −Hc to + Hc with respect to the external magnetic field changing along the X-axis as shown by the solid line in FIG. The output voltage Vxout is shown, and as shown by the broken line in FIG. 48, the output voltage is substantially “0” for the external magnetic field changing along the Y axis.

  Similar to the X-axis magnetic sensor, the Y-axis magnetic sensor is configured by connecting the first to fourth Y-axis GMR elements 71 to 74 in a full bridge connection. The pad 77 and the pad 78 are connected to a positive electrode and a negative electrode of a constant voltage source (not shown), and a potential Vyin + (5 (V) in this example) and a potential Vyin− (0 (V) in this example) are applied. The potential difference between the pad 75 and the pad 76 is taken out as the sensor output Vyout. As a result, the Y-axis magnetic sensor changes substantially in proportion to the external magnetic field in the range of −Hc to + Hc with respect to the external magnetic field changing along the Y-axis, as shown by the broken line in FIG. The output voltage Vyout is shown, and as shown by the solid line in FIG. 49, the output voltage is substantially “0” for the external magnetic field changing along the X axis.

  Next, a method for manufacturing the magnetic sensor 60 configured as described above will be described. First, as shown in FIG. 50, which is a plan view, a film M made of the spin valve film SV and the bias magnet film 61b on a rectangular quartz glass 60a1 and later forming individual GMR elements is formed as islands. A plurality are formed in a shape. This film formation is performed by continuous lamination to a precise thickness using an ultrahigh vacuum apparatus. When the quartz glass 60a1 is cut along the broken line in FIG. 50 and divided into the individual chips 60a shown in FIG. 42 in these films M, the GMR elements 61 to 61 shown in FIG. 64, 71 to 74. In addition, alignment (positioning) marks 60b having a shape obtained by removing a cross from a rectangle are provided at four corners of the quartz glass 60a1.

  Next, as shown in FIG. 51, which is a plan view, and FIG. 52, which is a cross-sectional view taken along the line 3-3 in FIG. 51, a plurality of square through holes are provided in a square lattice shape. A rectangular metal plate 81 (that is, square through holes having sides parallel to the X axis and the Y axis are provided equidistant from each other along the X axis and the Y axis); Each of the through holes of the metal plate 81 has rectangular parallelepiped permanent bar magnets 82... 82 having substantially the same square cross section as the through holes. The end surfaces of the permanent bar magnets 82. Insert so that it is parallel to. At this time, the permanent bar magnets 82... 82 are arranged so that the polarities of the adjacent magnetic poles are different at the shortest distance. The permanent bar magnets 82... 82 have substantially the same magnetic charge.

  Next, as shown in FIG. 53 which is a plan view, a plate 83 made of transparent quartz glass having a thickness of about 0.5 mm and having a rectangular shape substantially the same as the metal plate 81 is prepared. The plate 83 is provided with cross-shaped alignment (positioning) marks 83a at four corners in order to perform positioning in cooperation with the alignment mark 60b of the quartz glass 60a1. Further, an alignment mark 83b is provided at a position corresponding to the outer shape of the permanent bar magnets 82... 82 inserted in the metal plate 81 at the center. Next, as shown in FIG. 54, the upper surfaces of the permanent bar magnets 82... 82 and the lower surface of the plate 83 are bonded with an adhesive. At this time, the relative positions of the permanent bar magnets 82... 82 and the plate 83 are determined using the alignment mark 83b. Then, the metal plate 81 is removed from below. At this stage, the permanent bar magnets 82... 82 and the plate 83 are used to dispose a plurality of permanent magnets whose end faces are substantially square at the lattice points of the square lattice, and the polarities of the magnetic poles of each permanent magnet are the shortest distance. A magnet array is formed so as to be different from the polarities of other magnetic poles adjacent to each other with a gap therebetween.

  Next, as shown in FIG. 55, a quartz glass 60a1 on which a film to be a GMR element (a layer including a magnetic layer serving as a pinned layer, that is, a layer including a magnetic layer serving as a pinned layer) is formed is replaced with the GMR element. The surface on which the film to be formed is disposed so as to be in contact with the upper surface of the plate 83. The relative positions of the quartz glass 60a1 and the plate 83 are accurately determined by matching the portion of the alignment mark 60b that has been deleted in the cross shape with the cross shape of the alignment mark 83a.

  FIG. 56 is a perspective view showing a state where only four permanent bar magnets 82... 82 are taken out. As is clear from this figure, on the upper surface of the permanent bar magnets 82... 82, magnetic fields having different directions by 90 ° from one N pole to the S pole adjacent to the N pole at the shortest distance are formed. Therefore, in the state where the quartz glass 60a1 is placed on the upper surface of the plate 83 shown in FIG. 55, as schematically shown in FIG. 57, it is arranged in parallel with each side of one N-pole square end face. In addition, a magnetic field in the Y-axis positive direction, the X-axis positive direction, the Y-axis negative direction, and the X-axis negative direction is applied to each film that becomes the GMR.

  In the present embodiment, heat treatment is performed to fix the magnetization direction of the pinned layer P (the pinned layer of the pinned layer P) using such a magnetic field. That is, in the state shown in FIG. 55, the plate 83 and the quartz glass 60a1 are fixed to each other by the clamp CL, they are heated to 250 ° C. to 280 ° C. in a vacuum, and left in that state for about 4 hours.

  Thereafter, the quartz glass 60a1 is taken out to form the pads 65 to 68 and 75 to 78 shown in FIG. 42, and wirings for connecting these are formed. Finally, the quartz glass 60a1 is taken along the broken line shown in FIG. Disconnect. Thus, the magnetic sensor 60 shown in FIG. 42 is manufactured.

  Next, the result of measuring the geomagnetism using the magnetic sensor 60 will be described. In this measurement, as shown in FIG. 58, the azimuth θ (measurement angle) is defined as 0 ° when the positive Y-axis direction of the magnetic sensor 60 faces south. The measurement results are shown in FIG. As is clear from FIG. 59, the X-axis magnetic sensor output Sx indicated by the solid line changed in a sine wave shape, and the Y-axis magnetic sensor output Sy indicated by the broken line changed in a cosine wave shape. This result was as predicted from the characteristics shown in FIGS.

  In this case, (1) when both the X-axis magnetic sensor output Sx and the Y-axis magnetic sensor output Sy are positive values, θ = arctan (Sx / Sy), and (2) the Y-axis magnetic sensor output Sy. Θ = 180 ° + arctan (Sx / Sy) when the value is a negative value, (3) θ = when the value of the X-axis magnetic sensor output Sx is a negative value, and the output Sy of the Y-axis magnetic sensor is a positive value Since the orientation can be obtained by 360 ° + arctan (Sx / Sy), the magnetic sensor 60 can be used as a geomagnetic (orientation) sensor that can be mounted on a portable electronic device such as a mobile phone. When the azimuth is 270 to 360 ° and display is allowed as −90 to 0 °, θ = arctan (Sx / Sy) when the output Sy is positive, and θ when the output Sy is negative. = 180 ° + arctan (Sx / Sy).

  As described above, according to the third embodiment, a plurality of permanent magnets are disposed at lattice points of a square lattice, and the polarities of the magnetic poles of the permanent magnets are adjacent to each other with a shortest distance. Are prepared, and the magnetization direction of the magnetic layer to be the pinned layer is pinned by the magnetic field formed by the magnet array, so that the pinned magnetization directions of the pinned layer are different from each other (mutually An (orthogonal) GMR element can be easily formed on a single chip. Further, according to this method, a single chip including GMR elements having different pinned magnetization directions of the pinned layer can be manufactured in large quantities at a time, so that the manufacturing cost of the single chip is reduced. be able to.

  In addition, this invention is not limited to the said embodiment, A various modification can be employ | adopted within the scope of the present invention. For example, in the first and second embodiments, NiCо having a large residual magnetization is used as the plating film, but another material having a large residual magnetization (such as Co) may be used instead. Further, the method of fixing the magnetization direction of the pinned layer of the first and second embodiments is applied to other magnetoresistive effect elements having a pinned layer (layer having a fixed magnetization axis) as in the third embodiment. Can be applied. Further, although PtMn is used for the pinned layer P of the above three embodiments, FeMn, IrMn, or the like may be used instead of this PtMn.

It is a notional top view of the magnetic sensor concerning a 1st embodiment and a 2nd embodiment of the present invention. FIG. 2 is an enlarged plan view of the magnetic tunnel effect element (group) shown in FIG. 1. It is sectional drawing which cut | disconnected the magnetic tunnel effect element (group) shown in FIG. 2 by the plane along the 1-1 line. FIG. 4 is a schematic plan view of the element showing an antiferromagnetic film and a ferromagnetic film (pinned layer) of the magnetic tunnel effect element shown in FIG. 3. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic plan view of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 1st Embodiment in the middle of manufacture. A graph showing a change in MR ratio of the magnetic tunnel effect element (group) shown in FIG. 1 when an external magnetic field whose magnitude changes in the longitudinal direction (X-axis direction) of the element is applied. It is. The MR ratio of the magnetic tunnel effect element (group) shown in FIG. 1 when an external magnetic field whose magnitude changes in the direction perpendicular to the longitudinal direction of the element (Y-axis direction) is applied. It is a graph which shows a change. The MR ratio of the magnetic tunnel effect element (group) shown in FIG. 1 when an external magnetic field whose magnitude changes in the direction perpendicular to the longitudinal direction of the element (X-axis direction) is applied. It is a graph which shows a change. The graph which shows the change of MR ratio of the same element when the external magnetic field which changes the magnitude | size in the longitudinal direction (Y-axis direction) of the same element is given to the other magnetic tunnel effect element (group) shown in FIG. It is. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. It is a schematic sectional drawing of the magnetic sensor of 2nd Embodiment in the middle of manufacture. The MR ratio of the magnetic tunnel effect element (group) according to the second embodiment when an external magnetic field whose magnitude changes in the longitudinal direction of the element (X-axis direction in FIG. 1) is applied. It is a graph which shows a change. The same element when a magnetic tunnel effect element (group) according to the second embodiment is applied with an external magnetic field whose size changes in a direction perpendicular to the longitudinal direction of the element (Y-axis direction in FIG. 1) It is a graph which shows the change of MR ratio. The same element when another magnetic tunnel effect element (group) according to the second embodiment is applied with an external magnetic field whose size changes in the direction perpendicular to the longitudinal direction of the element (X-axis direction in FIG. 1) It is a graph which shows the change of MR ratio. MR ratio of the element when an external magnetic field whose magnitude changes in the longitudinal direction (Y-axis direction in FIG. 1) of the element is applied to the other magnetic tunnel effect element (group) according to the second embodiment. It is a graph which shows a change. 2 shows magnetization curves of a pinned layer and a free layer when a magnetic field whose magnitude changes in a direction orthogonal to the direction of magnetization of the pinned layer is applied to the magnetic tunnel effect element groups according to the first and second embodiments. It is a graph. It is a top view of the board | substrate in which the plating film which has another shape was formed. It is a schematic plan view of the magnetic sensor which concerns on 3rd Embodiment by this invention. FIG. 43 is a schematic enlarged plan view of the first X-axis GMR element shown in FIG. 42. FIG. 44 is a schematic cross-sectional view of the first X-axis GMR element shown in FIG. 43 cut along a plane along line 2-2 in FIG. 43. FIG. 44 is a diagram showing a spin valve film configuration of the first X-axis GMR element shown in FIG. 43. 44 is a graph showing changes in the resistance value (solid line) with respect to the magnetic field changing in the X-axis direction and the resistance value (broken line) with respect to the magnetic field changing in the Y-axis direction of the first X-axis GMR element shown in FIG. FIG. 43 is an equivalent circuit diagram of an X-axis magnetic sensor included in the magnetic sensor shown in FIG. 42. 48 is a graph showing changes in the output voltage (solid line) with respect to the magnetic field changing in the X-axis direction and the output voltage (broken line) with respect to the magnetic field changing in the Y-axis direction of the X-axis magnetic sensor shown in FIG. 43 is a graph showing changes in the output voltage (solid line) for a magnetic field changing in the X-axis direction and the output voltage (broken line) for a magnetic field changing in the Y-axis direction of the Y-axis magnetic sensor included in the magnetic sensor shown in FIG. . FIG. 43 is a plan view of quartz glass on which a spin valve film in the middle of manufacturing the magnetic sensor shown in FIG. 42 is formed. It is a top view of the metal plate for preparing the magnet array used when manufacturing the magnetic sensor shown in FIG. FIG. 52 is a cross-sectional view of the metal plate and the permanent bar magnet shown in FIG. 51 cut along a plane along line 3-3 in FIG. It is a top view of the plate for forming the magnet array used when manufacturing the magnetic sensor shown in FIG. It is sectional drawing of the magnet array used when manufacturing the magnetic sensor shown in FIG. FIG. 43 is a cross-sectional view showing a step of manufacturing the magnetic sensor shown in FIG. 42. FIG. 55 is a perspective view of a part of the magnets of the magnet array shown in FIG. 54 taken out. FIG. 43 is a conceptual diagram showing a method of pinning the magnetization direction of the pinned layer of each GMR element of the magnetic sensor shown in FIG. 42. It is the figure which showed the relationship between the magnetic sensor shown in FIG. 42, and an azimuth | direction. 43 is a graph showing an output voltage with respect to the direction of the magnetic sensor shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Substrate, 12 ... Lower electrode, 13 ... Antiferromagnetic film, 14 ... Ferromagnetic film, 15 ... Insulating layer, 16 ... Ferromagnetic film, 17 ... Dummy film, 18 ... Interlayer insulating layer, 18a ... Contact hole, 19 ... upper electrode, 20 ... protective film, 30 ... coil, 11, 21 ... magnetic tunnel effect element group, 51 ... resist.

Claims (5)

A magnetic sensor comprising a giant magnetoresistive element including a pinned layer and a free layer, the resistance value of which changes according to the relative angle between the direction of magnetization of the pinned layer and the direction of magnetization of the free layer,
A single chip having a substantially square shape, which is formed by cutting one substrate and has sides along the X axis and the Y axis perpendicular to each other in plan view ,
A total of eight giant magnetoresistive elements formed on the chip;
With
The eight giant magnetoresistive elements are:
A first X-axis GMR element formed in the vicinity of the end of the X-axis negative direction below the center of the chip in the Y-axis direction and in the first direction along the X-axis.
A second X-axis GMR element formed in the vicinity of an end in the negative X-axis direction at a position approximately above the center in the Y-axis direction of the chip, wherein the pinned layer has a pinned magnetization direction in the first direction;
A third X-axis GMR formed in the vicinity of the positive end of the X-axis in the vicinity of the positive end of the X-axis above the center of the chip in the Y-axis direction, and the pinned magnetization direction of the pinned layer is opposite to the first direction along the X-axis Elements,
The fourth X-axis GMR is formed in the vicinity of the positive end of the X-axis in the lower part of the Y-axis direction of the chip and in the vicinity of the positive end of the X-axis, and the pinned magnetization direction of the pinned layer is opposite to the first direction along the X-axis. Elements,
A first Y-axis GMR element formed in the vicinity of the Y-axis positive direction end on the left side of the center of the chip in the X-axis direction and in the second direction along the Y-axis.
A second Y-axis GMR element formed in the vicinity of the Y-axis positive direction end on the right side of the center in the X-axis direction of the chip, and the pinned magnetization direction of the pinned layer in the second direction;
A third Y-axis formed in the vicinity of the Y-axis negative direction end on the right side of the center of the chip in the X-axis direction and in the direction opposite to the second direction along the Y-axis. A GMR element;
A fourth Y-axis formed in the vicinity of the Y-axis negative direction end on the left side of the center of the chip in the X-axis direction and in the direction opposite to the second direction along the Y-axis. A GMR element;
Consists of
The first to fourth X-axis GMR elements constitute an X-axis magnetic sensor that exhibits an output voltage that changes substantially in proportion to the external magnetic field that changes along the X-axis by being fully bridged,
The first to fourth Y-axis GMR elements constitute a Y-axis magnetic sensor that exhibits an output voltage that changes substantially in proportion to the external magnetic field that changes along the Y-axis by being fully bridged. Yes,
Magnetic sensor.   The magnetic sensor according to claim 1,
  The magnetization directions of the pinned layers of the eight giant magnetoresistive elements are arranged such that a plurality of permanent magnets whose end faces are substantially square are arranged at square lattice points and the polarities of the magnetic poles of the permanent magnets. Is a magnetic sensor fixed by using a magnetic field formed by a magnet array that is configured to be different from the polarity of other magnetic poles adjacent to each other with a shortest distance. The magnetic sensor according to claim 1 or 2, wherein
Each of the eight giant magnetoresistance effect elements includes a pinned layer made of PtMn for fixing the magnetization direction of the pinned layer . A magnetic sensor according to any one of claims 1 to 3 ,
A magnetic sensor comprising a wiring for connecting the eight giant magnetoresistive elements to the single chip. A magnetic sensor according to any one of claims 1 to 3 ,
A magnetic sensor in which a plurality of pads are provided on the single chip and wiring for connecting the eight giant magnetoresistive elements and the plurality of pads is formed on the single chip.

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