JP2013044545A - Magnetic sensor device and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic sensor device capable of detecting three axial directions without combining a plurality of chips, and a manufacturing method of the magnetic sensor device.SOLUTION: A magnetic sensor device includes: a substrate 10; a base sacrificial layer 20 provided on the substrate 10; and a flexible layer 30 contacting with the base sacrificial layer 20, and having one surface 31 with an area of a part contacting with the base sacrificial layer 20 being larger than the base sacrificial layer 20. A plurality of magnetic resistance element portions 42 are provided on the flexible layer 30. A direction of magnetization of a pin magnetic layer 42a of one of the magnetic resistance element portions 42 is turned in parallel with a surface 11 of the substrate 10, thereby detecting magnetization in an X-axis direction or a Y-axis direction. The flexible layer 30 is warped in a semi-cylindrical shape from a contact place with the base sacrificial layer 20, so that the direction of the magnetization of the pin magnetic layer 42a of one of the magnetic resistance element portions 42 is tilted in the X-axis direction and the Y-axis direction, thereby detecting magnetization in a Z-axis direction.

Description

  The present invention relates to a magnetic sensor device and a manufacturing method thereof.

  As a known technique, a magnetic sensor that detects a rotation angle of an object using a GMR element (Giant Magneto Resistance; GMR) or a TMR element (Tunneling Magneto Resistance; TMR) having a free magnetic layer and a pinned magnetic layer is known. Yes. In these elements, the angle can be detected by changing the output of the element due to the difference between the magnetization direction of the pinned magnetic layer fixed in one direction and the magnetization direction of the free magnetic layer affected by the external magnetic field.

  Usually, the magnetization direction of the pinned magnetic layer is determined by annealing at about 300 ° C. while applying a magnetic field. In this case, since each pin magnetic layer is magnetized while applying a magnetic field to the entire wafer on which a plurality of elements are formed, the magnetization directions of the pin magnetic layers are all the same in one wafer. Therefore, it is possible to perform magnetic detection in the stacking direction of the elements and a plane (XY plane) perpendicular thereto. However, since it is impossible to detect a magnetic field in the magnetic film stacking direction (Z direction), a sensor element capable of detecting three axes is required.

  Therefore, in Patent Document 1, the direction of the detected magnetization of each magnetic sensor intersects with each other in the three-dimensional direction on each inclined surface of the substrate having a plurality of inclined surfaces in which the normal directions of the inclination intersect three-dimensionally. A configuration has been proposed in which magnetic sensors are respectively arranged.

  Further, in Patent Document 2, the substrate is provided with a movable portion and a plurality of magnetic sensors formed at positions including the movable portion, and at least one movable portion is mechanically separated from other movable portions. A configuration has been proposed that enables detection in three axial directions by tilting by applying a simple force.

JP 2009-20092 A JP 2010-66030 A

  However, in Patent Document 1, it is necessary to form an inclination on the substrate and arrange a magnetic sensor on the inclination. There is a problem that it is very difficult to form such a structure. Similarly, in Patent Document 2, it is necessary to form a movable part on the substrate and apply a mechanical force to the movable part. For this reason, there is a problem that the structure becomes complicated and the manufacture becomes difficult.

  Further, in order to detect the magnetic field in the Z direction, there is a method of combining the chips for detecting the magnetic field in an upright position with respect to the substrate. However, this method is also complicated in assembly and leads to an increase in cost. There is a need for a sensor chip that can be detected in three axial directions with the chip.

  An object of this invention is to provide the magnetic sensor apparatus which can detect a triaxial direction, and its manufacturing method, without combining several chip | tips in view of the said point.

  In order to achieve the above object, according to the first aspect of the present invention, a substrate (10) having a surface (11), a base sacrificial layer (20) provided on the surface (11) of the substrate (10), And a flexible layer (30) having a surface (31) in contact with the sacrificial layer (20) and having an area of a portion in contact with the base sacrificial layer (20) larger than that of the base sacrificial layer (20). A free magnetic layer (42c) whose magnetization direction changes under the influence of the magnetic field, and a pinned magnetic layer (42a) whose magnetization direction is fixed, and is formed on the flexible layer (30). The magnetoresistive element part (42) is provided.

  In addition, the magnetization directions of the pinned magnetic layers (42a) of the plurality of magnetoresistive element portions (42) are each directed in one direction parallel to the one surface (31) of the flexible layer (30).

  The magnetic sensor device detects physical quantities based on changes in resistance values of the plurality of magnetoresistive elements (42) when the plurality of magnetoresistive elements (42) are affected by an external magnetic field, A direction parallel to the surface (11) of the substrate (10) is defined as an X axis, and a direction perpendicular to the X axis in the surface (11) of the substrate (10) is defined as a Y axis, which is perpendicular to the X axis and the Y axis. The direction is the Z axis, and the following points are characteristic.

  That is, the magnetization direction of a part of the pin magnetic layer (42a) of the plurality of magnetoresistive element portions (42) is directed parallel to the surface (11) of the substrate (10), so that the X axis A physical quantity in the direction or the Y-axis direction is detected.

  The flexible layer (30) is warped starting from the contact portion with the base sacrificial layer (20), and a part of the pin magnetic layer (42a) different from a part of the plurality of magnetoresistive element parts (42). The physical quantity in the Z-axis direction is detected by tilting the magnetization direction of X with respect to the X-axis and the Y-axis.

  As described above, since the flexible layer (30) in which the plurality of magnetoresistive element portions (42) are formed is warped, the magnetization of the pin magnetic layer (42a) of the plurality of magnetoresistive element portions (42). The direction of is not only the X-axis and Y-axis directions which are the surface directions of the surface (11) of the substrate (10) but also the Z-axis direction perpendicular to the surface (11) of the substrate (10). Can do. Therefore, detection in the triaxial direction can be performed without combining a plurality of chips.

  As in the invention described in claim 2, the flexible layer (30) is warped in a semi-cylindrical shape.

  As in the invention described in claim 3, the flexible layer (30) is warped in a cylindrical shape.

  As in the invention described in claim 4, the flexible layer (30) is warped in a bowl shape.

  The invention according to claim 5 is characterized in that the flexible layer (30) is covered with a protective member (50). Thereby, the flexible layer (30) can be protected by the protective member (50).

  In the invention described in claim 6, first, the substrate (10) is prepared, and the base layer (21) is formed on the surface (11) of the substrate (10). A flexible layer (30) is formed on the base layer (21), and a plurality of magnetoresistive element portions (42) are formed on the flexible layer (30).

  Thereafter, the plurality of magnetoresistive element portions (42) are arranged in a magnetic field in which the direction of the magnetic field is set to one direction of the surface (31) of the one surface (31) of the flexible layer (30), and the plurality of magnetoresistive element portions ( 42) is heated and annealed in a magnetic field, so that the magnetization directions of the pinned magnetic layers (42a) constituting the plurality of magnetoresistive element portions (42) are each magnetized in one direction.

  Subsequently, the base layer (21) so that the area of the portion of the base layer (21) that contacts one surface (31) of the flexible layer (30) is smaller than the area of the one surface (31) of the flexible layer (30). A base sacrificial layer (20) is formed by removing a part of the substrate.

  A direction parallel to the surface (11) of the substrate (10) is defined as an X axis, and a direction perpendicular to the X axis in the surface (11) of the substrate (10) is defined as a Y axis, which is perpendicular to the X axis and the Y axis. The direction is defined as the Z axis. Then, the magnetization direction of a part of the pinned magnetic layer (42a) of the plurality of magnetoresistive element portions (42) is made by warping the flexible layer (30) starting from the contact portion with the base sacrificial layer (20). Is directed in a plane direction parallel to the surface (11) of the substrate (10), and the magnetization direction of a part of the pin magnetic layer (42a) different from a part of the plurality of magnetoresistive element portions (42) is changed to the substrate ( It is characterized by being inclined with respect to the surface (11) of 10).

  Thus, since the flexible layer (30) in which the plurality of magnetoresistive element portions (42) are formed is warped, the magnetization direction of the pin magnetic layer (42a) of the plurality of magnetoresistive element portions (42) is changed to the substrate ( It can be tilted with respect to the surface (11) of the substrate (10) as well as the plane direction parallel to the surface (11) of 10). Therefore, it is possible to manufacture a magnetic sensor device that performs detection in three axial directions without combining a plurality of chips.

  As in the seventh aspect of the invention, in the step of warping the flexible layer (30), the flexible layer (30) can be warped in a semi-cylindrical shape.

  In the step of warping the flexible layer (30), the flexible layer (30) can be warped in a cylindrical shape.

  In the step of warping the flexible layer (30) as in the ninth aspect of the invention, the flexible layer (30) can be warped in a bowl shape.

  The invention according to claim 10 includes a step of covering the flexible layer (30) with a protective member (50) after the step of warping the flexible layer (30). Thereby, the flexible layer (30) can be protected by the protective member (50).

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

1 is a schematic perspective view of a magnetic sensor device according to a first embodiment of the present invention. It is a schematic sectional drawing of the sensor part shown by FIG. It is the figure which showed the manufacturing process of the magnetic sensor apparatus shown by FIG. 1 and FIG. It is the figure which showed the manufacturing process following FIG. It is the figure which showed the magnetization process following FIG. It is the figure which showed the manufacturing process following FIG. It is a schematic perspective view of the magnetic sensor apparatus which concerns on 2nd Embodiment of this invention. It is a schematic perspective view of the magnetic sensor apparatus which concerns on 3rd Embodiment of this invention. It is a schematic perspective view of the magnetic sensor apparatus which concerns on 4th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, the same or equivalent parts are denoted by the same reference numerals in the drawings.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The magnetic sensor device according to the present embodiment is used, for example, for detecting engine rotation speed and steering wheel rotation angle for automobiles. In the present embodiment, a rotation angle sensor that detects a rotation angle will be described as an example of a magnetic sensor device.

  FIG. 1 is a schematic perspective view of a magnetic sensor device according to the present embodiment. As shown in FIG. 1, the magnetic sensor device has a configuration in which a flexible layer 30 is provided via a base sacrificial layer 20 provided on the surface 11 of the substrate 10. For example, a Si substrate is used as the substrate 10.

  Here, one direction parallel to the surface 11 of the substrate 10 (the longitudinal direction of the substrate 10 in FIG. 1) is defined as the X axis, and the direction perpendicular to the X axis in the surface 11 of the substrate 10 is defined as the Y axis. A direction perpendicular to the X axis and the Y axis, that is, a direction perpendicular to the surface 11 of the substrate 10 is defined as a Z axis.

The base sacrificial layer 20 plays a role of supporting the flexible layer 30 and is made of an insulating material such as SiO ₂ . In the present embodiment, the base sacrificial layer 20 forms a rectangular parallelepiped along the Y-axis direction, and is located at the center of the flexible layer 30 in the X-axis direction. That is, the base sacrificial layer 20 supports the flexible layer 30 with lines.

  The flexible layer 30 is a layer having flexibility, and has a surface 31 that contacts the base sacrificial layer 20. The one surface 31 is wider than a portion in contact with the base sacrificial layer 20. That is, the area of the one surface 31 of the flexible layer 30 is larger than the area of the portion where the base sacrificial layer 20 contacts the flexible layer 30.

  The flexible layer 30 is warped in a semi-cylindrical shape as shown in FIG. The “semi-cylindrical shape” is a shape obtained by dividing a cylinder along an axis. It can also be said that the cross section has a semicircular arc shape. PDMS or SiN is used as the material of the flexible layer 30. A portion of the flexible layer 30 that is not in contact with the base sacrificial layer 20 is warped.

  The flexible layer 30 includes three sensor units 40. The sensor unit 40 is an element whose resistance value changes when affected by an external magnetic field. The sensor unit 40 according to the present embodiment is configured as a tunnel magnetoresistive element (TMR element).

  FIG. 2 is a schematic sectional view of the sensor unit 40. As shown in this figure, the sensor unit 40 includes a lower electrode 41, a magnetoresistive element unit 42 provided on the lower electrode 41, an upper electrode 43 provided on the magnetoresistive element unit 42, It has.

  The magnetoresistive element portion 42 is configured by forming a pin magnetic layer 42a, a tunnel layer 42b, and a free magnetic layer 42c in this order on a lower electrode 41 to constitute a TMR element. The pinned magnetic layer 42a is a ferromagnetic metal layer that is positioned closer to the base sacrificial layer 20 than the free magnetic layer 42c and has a fixed magnetization direction. The tunnel layer 42b is an insulating layer for allowing a current to flow from the free magnetic layer 42c to the pinned magnetic layer 42a by the tunnel effect. The free magnetic layer 42c is a ferromagnetic metal layer whose magnetization direction changes under the influence of an external magnetic field.

  Before the flexible layer 30 is warped as shown in FIG. 1, the magnetization direction of the pinned magnetic layer 42 a of the plurality of magnetoresistive element portions 42 is one direction parallel to the one surface 31 of the flexible layer 30 (X The flexible layer 30 is warped in a U-shape as shown in FIG. It can be said that after the flexible layer 30 is warped, the magnetization direction of the pinned magnetic layer 42a is directed to the tangential direction of the warp curve of the flexible layer 30.

  As the flexible layer 30 is warped in this manner, one of the three pinned magnetic layers 42a is directed in the −Z axis direction, one is directed in the X axis direction, and one is + Z axis. Is directed in the direction. According to this, the magnetoresistive element unit 42 in which the magnetization direction of the pinned magnetic layer 42a is directed in the X-axis direction can detect a magnetic field in the XY plane, and the magnetization direction of the pinned magnetic layer 42a is ± Z. The magnetoresistive element 42 oriented in the axial direction can detect a magnetic field in the Z-axis direction.

  The sensor unit 40 is laid out in a circular shape as shown in FIG. The reason why the planar layout of the sensor unit 40 is thus circular is that the magnetization characteristics are improved. An ellipse may be used instead of a perfect circle. Of course, the planar layout of the sensor unit 40 is not limited to a circle or an ellipse, but may be a polygon.

  The lower electrode 41 is connected to a lower electrode pad (not shown) formed on the substrate 10 via a lower electrode wiring (not shown) connected to the lower electrode 41. The lower electrode wiring is formed so as to penetrate the base sacrificial layer 20. The lower electrode pad is connected to a signal processing chip (not shown).

  The upper electrode 43 is connected to an upper electrode pad (not shown) through an upper electrode wiring (not shown) connected to the upper electrode 43. The upper electrode pad is connected to a signal processing chip (not shown).

  The above is the configuration of the magnetic sensor device according to the present embodiment. Next, a method for manufacturing the magnetic sensor device having the above configuration will be described with reference to FIGS. In addition, in each figure of FIG.3, FIG4 and FIG.6 (a), sectional drawing of the structure which used the two magnetoresistive element parts 42 as one sensor part 40 is shown. In FIG. 6B, the structure in the flexible layer 30 is omitted.

  First, in the process shown in FIG. 3A, a Si substrate is prepared as the substrate 10. Then, by performing ion implantation on the surface 11 side of the substrate 10, a lower electrode pad 41a and a wiring (not shown) are formed.

In the step shown in FIG. 3B, a base layer 21 such as SiO ₂ is formed on the entire surface 11 of the substrate 10 by a method such as CVD or sputtering.

  Subsequently, in the process illustrated in FIG. 3C, the base film 32 of the flexible layer 30 is formed on the base layer 21. PDMS is used as the material of the flexible layer 30, and the base layer 21 is formed by coating (spin coating) on the base layer 21. When the material of the flexible layer 30 is SiN, a SiN film is formed on the substrate 10 by a CVD method or the like.

  In the step shown in FIG. 3D, a contact hole 41b penetrating the base film 32 and the base layer 21 is formed at a position corresponding to the lower electrode pad 41a by dry etching or the like, and Al, Cu or the like is formed in the contact hole 41b. As a result, the lower electrode wiring 41c is formed. The unnecessary metal layer on the base film 32 is removed.

  Thereafter, in the step shown in FIG. 3E, a metal layer to be the lower electrode 41 is formed on the base film 32 by sputtering or the like. Then, the lower electrode 41 is formed by etching by milling or the like. The lower electrode 41 is connected to the lower electrode wiring 41c.

  In the step shown in FIG. 4A, each layer to be the magnetoresistive element portion 42 is sequentially formed on the lower electrode 41 by sputtering or the like. Then, a pair of magnetoresistive element portions 42 are formed on each lower electrode 41 by etching by milling or the like.

  In the step shown in FIG. 4B, PDMS is applied on each magnetoresistive element portion 42 or an SiN film is formed by a CVD method or the like, and the PDMS or SiN film on each magnetoresistive element portion 42 is formed by a lift-off method. Remove. Thereby, the intermediate film 33 which is a part of the flexible layer 30 is configured to cover the side surface of the magnetoresistive element portion 42.

  In the step shown in FIG. 4C, a metal layer is formed on each magnetoresistive element portion 42 by sputtering or the like, and the upper electrode 43 is formed by etching the metal layer by milling or the like.

  4D, PDMS is applied or an SiN film is formed by a CVD method or the like so as to cover the upper electrode 43, and the protective film 34 which is a part of the flexible layer 30 is formed. That is, the flexible layer 30 includes the base film 32, the intermediate film 33, and the protective film 34.

  Subsequently, in the step shown in FIG. 5, the pinned magnetic layer 42 a of each magnetoresistive element unit 42 is magnetized. Specifically, each magnetoresistive element unit 42 is arranged in a magnetic field in which the direction of the magnetic field is set to one direction (X-axis direction) of the one surface 31 of the flexible layer 30. That is, the product obtained in the step of FIG. 4D is placed in a magnetic field. And each magnetoresistive element part 42 is heated and annealing in a magnetic field is performed. Thereby, the magnetization direction of the pinned magnetic layer 42a constituting each magnetoresistive element portion 42 is magnetized along the X-axis direction. Thus, it is not necessary to magnetize the pinned magnetic layers 42a of the magnetoresistive element portions 42 so that the magnetization directions thereof are different from each other, and they can be magnetized together.

  Thereafter, in the step shown in FIG. 6A, the area of the portion of the base layer 21 that contacts the one surface 31 of the flexible layer 30 is smaller than the area of the one surface 31 of the flexible layer 30 by wet etching or dry etching. Then, a part of the base layer 21 is removed. In the present embodiment, as described above, the base layer 21 is etched so that the base sacrificial layer 20 is located in the center of the flexible layer 30 in the X-axis direction and is a rectangular parallelepiped along the Y-axis direction. In this way, the base sacrificial layer 20 is formed from the base layer 21.

  In this way, when the flexible layer 30 is supported by the base sacrificial layer 20, as shown in FIG. 6A, the other end side of the flexible layer 30 opposite to the one end side in the X-axis direction Are separated from the substrate 10 and are in a floating state. That is, a space portion exists between a portion of the one surface 31 of the flexible layer 30 excluding the base sacrificial layer 20 and the surface 11 of the substrate 10.

  In the step shown in FIG. 6B, the flexible layer 30 is warped starting from the contact portion with the base sacrificial layer 20. For example, the flexible layer 30 is warped into a semi-cylindrical shape by a method of causing the flexible layer 30 to be thermally compressed by performing a heat treatment. As a result, the flexible layer 30 is warped in a U shape so that one end side in the X-axis direction and the other end side opposite to the substrate 10 are separated from the substrate 10.

  The reason why the flexible layer 30 is warped in this manner is to incline the magnetization direction of at least one pin magnetic layer 42 a of the plurality of magnetoresistive element portions 42 formed in the flexible layer 30 with respect to the surface 11 of the substrate 10. That is, by deflecting the flexible layer 30, the magnetization direction of one pinned magnetic layer 42 a of the plurality of magnetoresistive element parts 42 is directed in a plane direction parallel to the surface 11 of the substrate 10, and the other magnetoresistive element parts The magnetization direction of the pinned magnetic layer 42 a of 42 is inclined with respect to the surface 11 of the substrate 10. Thus, the magnetic sensor device shown in FIG. 1 is completed.

  Next, a method for detecting a rotation angle as a physical quantity when the magnetic sensor device is affected by an external magnetic field will be described. In order to detect the rotation angle, a current is passed through the magnetoresistive element portion 42 via the lower electrode pad and the upper electrode pad.

  Since each magnetoresistive element unit 42 is affected by an external magnetic field, the magnitude of the current flowing through each magnetoresistive element unit 42 based on the change in the resistance value of each magnetoresistive element unit 42, that is, the resistance value is Change.

  Here, among the plurality of magnetoresistive element portions 42, those in which the magnetization direction of the pinned magnetic layer 42a is oriented in a plane direction (X-axis direction) parallel to the surface 11 of the substrate 10 is X-axis direction or Y-axis. The magnetic field in the direction (the magnetic field in the XY plane) can be detected. On the other hand, when the flexible layer 30 is warped, the magnetization direction of the pinned magnetic layer 42a among the plurality of magnetoresistive element portions 42 is tilted with respect to the surface 11 of the substrate 10 (that is, the X axis and the Y axis). For, the magnetization in the Z-axis direction can be detected. Therefore, detection in three axial directions is possible without combining a plurality of chips.

  As described above, the present embodiment is characterized in that the flexible layer 30 in which the plurality of magnetoresistive element portions 42 are formed is warped in a semi-cylindrical shape starting from the base sacrificial layer 20. As a result, the magnetization direction of the pinned magnetic layer 42a of the plurality of magnetoresistive element portions 42 is not limited to the X-axis and Y-axis directions that are the surface directions of the surface 11 of the substrate 10, but also the Z-axis perpendicular to the surface 11 of the substrate 10 It can also be in the state which turned to the direction. Therefore, detection in the triaxial direction can be performed without combining a plurality of chips.

  As for the correspondence between the description of the present embodiment and the description of the claims, the magnetoresistive element portion 42 in which the magnetization direction of the pinned magnetic layer 42a is directed in the X-axis direction is “a plurality of The magnetoresistive element portion 42 corresponding to the “part of the magnetoresistive element portion” and having the magnetization direction of the pinned magnetic layer 42 a oriented in the Z-axis direction is “part of the plurality of magnetoresistive element portions” in the claims. Corresponds to “parts different from”.

(Second Embodiment)
In the present embodiment, parts different from the first embodiment will be described. FIG. 7 is a schematic perspective view of the magnetic sensor device according to the present embodiment. As shown in this figure, the flexible layer 30 is covered with a protective member 50. As a material of the protection member 50, for example, a resin material is used.

  Thus, when manufacturing the structure which covers the flexible layer 30 with the protection member 50, if the process of covering the flexible layer 30 with the protection member 50 is performed after the process (process shown in FIG.6 (b)) which warps the flexible layer 30, it will carry out. good. Thus, the flexible layer 30 can be protected by covering the flexible layer 30 with the protective member 50.

(Third embodiment)
In the present embodiment, parts different from the first and second embodiments will be described. FIG. 8 is a schematic perspective view of the magnetic sensor device according to the present embodiment. As shown in this figure, the flexible layer 30 is warped in a cylindrical shape. Such a form is realized by warping the flexible layer 30 until one end side in the X-axis direction and the other end side opposite to the X-axis direction in the flexible layer 30 in the step shown in FIG. 6B. be able to.

  As described above, the magnetization direction of at least one pin magnetic layer 42a among the plurality of magnetoresistive element portions 42 formed in the flexible layer 30 due to the flexible layer 30 warping in a cylindrical shape is changed to the surface 11 of the substrate 10. Can be tilted against.

  In this embodiment, the cylindrical flexible layer 30 may be covered with the protective member 50 shown in the second embodiment.

(Fourth embodiment)
In the present embodiment, parts different from the first embodiment will be described. FIG. 9 is a schematic perspective view of the magnetic sensor device according to the present embodiment. As shown in this figure, the flexible layer 30 is warped in a bowl shape. Here, the “saddle shape” refers to the shape of a part of a spherical shell or the shape of a contact lens.

  As described above, since the flexible layer 30 is warped from the contact point with the base sacrificial layer 20, the base sacrificial layer 20 is pointed with respect to one surface 31 of the flexible layer 30 in order to warp the flexible layer 30 in a bowl shape. In contact. As described above, since the portion of the flexible layer 30 that is not in contact with the base sacrificial layer 20 is warped, the flexible layer 30 is centered on the base sacrificial layer 20 by supporting the flexible layer 30 with the base sacrificial layer 20. It is along the saddle shape.

  When a plurality of magnetoresistive element portions 42 are provided in such a bowl-shaped flexible layer 30, the pin magnetic layer 42 a of the magnetoresistive element portion 42 located in the central portion of the flexible layer 30 in the X-axis direction. The direction of magnetization is warped in the X-axis direction. In addition, the magnetization direction of the pinned magnetic layer 42a of the magnetoresistive element portion 42 located on one end side in the X-axis direction and the other end side on the opposite side of the flexible layer 30 is warped by the flexible layer 30. Therefore, it is inclined with respect to the surface 11 of the substrate 10. Thus, the detection in the triaxial direction can also be performed by bending the flexible layer 30 in a bowl shape.

  Of course, also in this embodiment, the cylindrical flexible layer 30 may be covered with the protective member 50 shown in the second embodiment.

(Other embodiments)
The configuration of the magnetic sensor device described in each of the above embodiments is merely an example, and is not limited to the configuration described above, and may be another configuration that can realize the present invention. For example, in each of the above embodiments, the magnetic sensor device has been described as being applied to a vehicle, but of course, it is not limited to a vehicle and can be widely used as a device that detects a rotation angle.

  In each of the above embodiments, the magnetoresistive element unit 42 is configured as a TMR element, but may be configured as a GMR element.

  Of course, the position of each sensor unit 40 in the flexible layer 30 shown in the above embodiments is merely an example, and the position of each sensor unit 40 can be appropriately set depending on which direction the magnetization direction of the pinned magnetic layer 42a is set. It ’s fine.

  In each of the above embodiments, the flexible layer 30 is warped in a semi-cylindrical shape, a cylindrical shape, and a bowl shape, but these shapes are merely examples, and may be in other shapes. For example, in the first embodiment, the flexible layer 30 is warped such that one end side in the X-axis direction and the other end side opposite to the flexible layer 30 are separated from the surface 11 of the substrate 10. The flexible layer 30 may be warped so that the one end side in the X-axis direction and the other end side on the opposite side approach the surface 11 of the substrate 10. The same applies to the bowl-shaped flexible layer 30 shown in the fourth embodiment, and the flexible layer 30 may be warped so as to approach the substrate 10.

  In each of the above-described embodiments, the flexible layer 30 has a three-layer structure including the base film 32, the intermediate film 33, and the protective film 34. However, this structure is an example, and the flexible layer 30 does not have a three-layer structure. May be. For example, it may be composed of one layer instead of a laminated structure.

  In each of the embodiments described above, heat treatment is performed as a method of warping the flexible layer 30, but the material may be warped by selecting the material of the flexible layer 30 depending on the physical properties of the flexible layer 30. Moreover, you may warp using a MEMS technique.

  In each of the above-described embodiments, the case where one magnetic sensor device is manufactured using one substrate 10 has been described. However, the pin magnetic layer 42a of each sensor unit 40 can be magnetized in the same direction. A method of manufacturing a large number of magnetic sensor devices from a single wafer may be employed by forming a portion to be a large number of magnetic sensor devices on a single wafer and dividing the wafer in a later process.

DESCRIPTION OF SYMBOLS 10 Substrate 11 Surface 20 Base sacrificial layer 30 Flexible layer 31 One surface 42 Magnetoresistive element part 42a Pin magnetic layer 42c Free magnetic layer 50 Protection member

Claims (10)

A substrate (10) having a surface (11);
A base sacrificial layer (20) provided on the surface (11) of the substrate (10);
A flexible layer (30) having a surface (31) in contact with the base sacrificial layer (20) and having an area of a portion in contact with the base sacrificial layer (20) larger than that of the base sacrificial layer (20);
A free magnetic layer (42c) whose magnetization direction changes under the influence of an external magnetic field, and a pinned magnetic layer (42a) whose magnetization direction is fixed, and is formed on the flexible layer (30). A plurality of magnetoresistive element portions (42);
With
The magnetization directions of the pinned magnetic layers (42a) of the plurality of magnetoresistive element portions (42) are respectively directed in one direction parallel to the one surface (31) of the flexible layer (30);
A magnetic sensor device for detecting a physical quantity based on a change in resistance value of the plurality of magnetoresistive element portions (42) when the plurality of magnetoresistive element portions (42) are affected by an external magnetic field,
A direction parallel to the surface (11) of the substrate (10) is defined as an X axis, and a direction perpendicular to the X axis in the surface (11) of the substrate (10) is defined as a Y axis. If the vertical direction is the Z axis,
The magnetization direction of a part of the pinned magnetic layer (42a) of the plurality of magnetoresistive element portions (42) is directed parallel to the surface (11) of the substrate (10), so that the X A physical quantity in the axial direction or the Y-axis direction is detected,
The flexible layer (30) warps starting from a contact portion with the base sacrificial layer (20), and a part of the pin magnetic layer (42a) different from a part of the plurality of magnetoresistive element portions (42). ) Is tilted with respect to the X-axis and the Y-axis, so that the physical quantity in the Z-axis direction is detected.   The magnetic sensor device according to claim 1, wherein the flexible layer (30) is warped in a semi-cylindrical shape.   The magnetic sensor device according to claim 1, wherein the flexible layer is warped in a cylindrical shape.   2. The magnetic sensor device according to claim 1, wherein the flexible layer (30) is warped.   The magnetic sensor device according to any one of claims 1 to 4, wherein the flexible layer (30) is covered with a protective member (50). A substrate (10) having a surface (11);
A base sacrificial layer (20) provided on the surface (11) of the substrate (10);
A flexible layer (30) having a surface (31) in contact with the base sacrificial layer (20) and having an area of a portion in contact with the base sacrificial layer (20) larger than that of the base sacrificial layer (20);
A free magnetic layer (42c) whose magnetization direction changes under the influence of an external magnetic field, and a pinned magnetic layer (42a) whose magnetization direction is fixed, and is formed on the flexible layer (30). A plurality of magnetoresistive element portions (42);
With
The magnetization directions of the pinned magnetic layers (42a) of the plurality of magnetoresistive element portions (42) are respectively directed in one direction parallel to the one surface (31) of the flexible layer (30);
A method of manufacturing a magnetic sensor device that detects a physical quantity based on a change in resistance value of the plurality of magnetoresistive element portions (42) when the plurality of magnetoresistive element portions (42) are affected by an external magnetic field. There,
Preparing the substrate (10);
Forming an underlayer (21) on the surface (11) of the substrate (10);
Forming the flexible layer (30) on the underlayer (21), and forming the plurality of magnetoresistive element portions (42) on the flexible layer (30);
The plurality of magnetoresistive element portions (42) are arranged in a magnetic field in which the direction of the magnetic field is set in one direction of the plane direction of the one surface (31) of the flexible layer (30), and the plurality of magnetoresistive element portions ( 42) magnetizing the magnetization directions of the pinned magnetic layers (42a) constituting the plurality of magnetoresistive element portions (42) in the one direction by heating in the magnetic field by heating 42),
Of the foundation layer (21), the foundation layer (21) is such that the area of the portion in contact with one surface (31) of the flexible layer (30) is smaller than the area of one surface (31) of the flexible layer (30). ) To form the base sacrificial layer (20),
A direction parallel to the surface (11) of the substrate (10) is defined as an X axis, and a direction perpendicular to the X axis in the surface (11) of the substrate (10) is defined as a Y axis. A vertical direction is defined as the Z-axis, and the flexible layer (30) is warped from the contact point with the base sacrificial layer (20) as a starting point, so that a part of the plurality of magnetoresistive element portions (42) The direction of magnetization of the pinned magnetic layer (42a) is directed in a plane direction parallel to the surface (11) of the substrate (10), and a part of the plurality of magnetoresistive element parts (42) is different from the part And a step of tilting the magnetization direction of the pinned magnetic layer (42a) with respect to the surface (11) of the substrate (10).   The method of manufacturing a magnetic sensor device according to claim 6, wherein in the step of warping the flexible layer (30), the flexible layer (30) is warped in a semi-cylindrical shape.   The method for manufacturing a magnetic sensor device according to claim 6, wherein in the step of warping the flexible layer (30), the flexible layer (30) is warped in a cylindrical shape.   The method of manufacturing a magnetic sensor device according to claim 6, wherein, in the step of warping the flexible layer (30), the flexible layer (30) is warped in a hook shape.   The magnetic according to any one of claims 6 to 9, further comprising a step of covering the flexible layer (30) with a protective member (50) after the step of warping the flexible layer (30). A method for manufacturing a sensor device.

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