JP2023048427A - magnetic sensor - Google Patents

Abstract

To improve measurement accuracy in a magnetic sensor.SOLUTION: A magnetic sensor includes: a substrate; and a lamination part arranged on the substrate. The lamination part includes: a magnetization free layer; a magnetization fixed layer where magnetization is fixed in a first direction; and a first non-magnetic layer arranged between the magnetization free layer and the magnetization fixed layer. The magnetization free layer includes: a second non-magnetic layer; and a first ferromagnetic layer and second ferromagnetic layer separated in the height direction by the second non-magnetic layer. Relation between a length W of the magnetization free layer in the first direction and a length L of the magnetization free layer in a second direction vertical to the first direction as viewed from above satisfies W/L>1.SELECTED DRAWING: Figure 2

Description

The present invention relates to magnetic sensors.

Conventionally, as a magnetic sensor for detecting a magnetic field, there is a magneto-resistance (MR) sensor using a giant magneto-resistance (GMR) effect or a tunnel magneto-resistance (TMR) effect. . (For example, see Patent Document 1 and Patent Document 2).
Patent Document 1: JP-A-9-199769 Patent Document 2: JP-A-2005-221383

In a magnetic sensor, it is desirable to improve the measurement accuracy.

To solve the above problems, one aspect of the present invention provides a magnetic sensor. A magnetic sensor may comprise a substrate. The magnetic sensor may comprise a laminate. The stack may be provided on the substrate. The lamination section may have a magnetization free layer. The lamination section may have a magnetization fixed layer. The magnetization fixed layer may have its magnetization fixed in the first direction. The laminated portion may have a first non-magnetic layer. The first non-magnetic layer may be arranged between the magnetization free layer and the magnetization fixed layer. The magnetization free layer may include a second non-magnetic layer. The magnetization free layer may include a first ferromagnetic layer and a second ferromagnetic layer. The first ferromagnetic layer and the second ferromagnetic layer may be separated in height by a second non-magnetic layer. The length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction perpendicular to the first direction in top view may satisfy W/L>1.

The length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction may satisfy W/L>1.43. The length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction may satisfy W/L<50.

A minimum distance D in the first direction between the outer edge of the magnetization free layer and the outer edge of the magnetization fixed layer may satisfy D>45 μm. A minimum distance D in the first direction between the outer edge of the magnetization free layer and the outer edge of the magnetization fixed layer may satisfy D<1 mm.

The magnetization free layer may be arranged between the substrate and the first non-magnetic layer.

The magnetization free layer may have an axisymmetric shape with an axis of symmetry parallel to the second direction when viewed from above. The position of the center of gravity of the magnetization fixed layer may be arranged at a position overlapping with the axis of symmetry when viewed from above.

A plurality of magnetization fixed layers may be arranged on one surface side of the magnetization free layer. The plurality of magnetization fixed layers may be arranged along the second direction.

Either or both the first ferromagnetic layer and the second ferromagnetic layer may be amorphous.

The magnetic sensor may comprise a magnetic concentrator. The magnetic concentrator may be electrically insulated from the magnetization free layer, the magnetization fixed layer and the first non-magnetic layer.

At least part of the magnetic concentrator may overlap with at least part of the magnetization free layer when viewed from above. At least part of the side surface of the magnetization free layer may overlap the magnetic concentrator in the first direction.

The length LP of the magnetization pinned layer in the second direction may be less than 125 μm.

A minimum distance D in the first direction between the outer edge of the magnetization free layer and the outer edge of the magnetization fixed layer and the length WP of the magnetization fixed layer in the first direction may satisfy D>WP.

The length W of the magnetization free layer in the first direction may be 1 mm or less.

The thickness of the side surface of the magnetization free layer may be smaller than the thickness of the region of the magnetization free layer that overlaps the magnetization fixed layer when viewed from above.

It should be noted that the above summary of the invention does not list all the features of the invention. Subcombinations of these feature groups can also be inventions.

1 is a diagram showing an example of a magnetic sensor 100 according to one embodiment of the invention; FIG. 2 is an example of a cross-sectional view taken along line X1-X1 in FIG. 1; FIG. 1 is a diagram explaining an outline of a magnetic sensor 100; FIG. FIG. 10 is a diagram showing an example of a magnetic sensor 200 according to another embodiment; FIG. 10 is a diagram showing an example of a magnetic sensor 300 according to another embodiment; 6 is an example of a cross-sectional view along Y3-Y3 in FIG. 5; FIG. FIG. 10 is a diagram showing an example of a magnetic sensor 400 according to another embodiment; FIG. 8 is an example of a cross-sectional view taken along the line Y4-Y4 of FIG. 7; FIG. 10 is a diagram showing an example of a magnetic sensor 500 according to another embodiment; FIG. 10 is an example of a cross-sectional view taken along the line X5-X5 of FIG. 9; FIG. 10 is a diagram showing an example of a magnetic sensor 600 according to another embodiment; FIG. 12 is an example of a cross-sectional view taken along line X6-X6 of FIG. 11; FIG. 12 is another example of a cross-sectional view along the line X6-X6 of FIG. 11; FIG. 7 is a diagram showing an example of a magnetic sensor 700 according to another embodiment; FIG. 10 is a diagram showing an example of a magnetic sensor 800 according to another embodiment; FIG. 7 is a diagram illustrating an example of a flowchart of a method for manufacturing the magnetic sensor 400; It is a figure explaining lamination|stacking part formation step S101. It is a figure explaining laminated part processing step S102. It is a figure explaining magnetization fixed layer processing step S103. It is a figure explaining wiring part formation step S104. FIG. 11 shows a magnetic sensor 1100 according to an embodiment; 12A and 12B are diagrams showing a magnetic sensor 1200 according to an embodiment; FIG. 13A and 13B are diagrams showing a magnetic sensor 1300 according to an embodiment; FIG. FIG. 14 is a diagram showing a magnetic sensor 1400 according to a comparative example; FIG. 15 is a diagram showing a magnetic sensor 1500 according to a comparative example; FIG. 15 is a diagram showing a magnetic sensor 1500 according to a comparative example; FIG. 4 is a diagram showing MR curves of the magnetic sensor 1100 and the magnetic sensor 1400; FIG. 4 is a diagram showing MR curves of a magnetic sensor 1200 and a magnetic sensor 1500; 4 is a table summarizing linearity of MR curves of the magnetic sensors 1100 to 1600. FIG. 1 is a list of magnetic sensors created for investigating the linearity of MR curves. FIG. 4 is a diagram showing the relationship between W/L and the linearity value of the MR curve; It is a figure which shows the relationship between D and the value of the linearity of an MR curve. FIG. 4 is a diagram showing the relationship between LP and linearity values of MR curves;

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution of the invention. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to omit redundant description, and elements that are not directly related to the present invention are not illustrated. omitted. Also, in one drawing, elements having the same function and configuration are represented by reference numerals, and other reference numerals are sometimes omitted.

In this specification, one side of the substrate on which the laminate is provided is referred to as "upper" and the other side on which no laminate is provided is referred to as "lower." One of the two main surfaces of a substrate, layer or other member is called the upper surface and the other surface is called the lower surface. The "up" and "down" directions are not limited to the direction of gravity or the direction when the magnetic sensor is mounted.

In this specification, technical matters may be described using X-, Y-, and Z-axis orthogonal coordinate axes. The Cartesian coordinate axes only specify the relative positions of the components and do not limit any particular orientation. For example, the Z axis does not limit the height direction with respect to the ground. Note that the +Z-axis direction and the −Z-axis direction are directions opposite to each other. When the Z-axis direction is described without indicating positive or negative, it means a direction parallel to the +Z-axis and -Z-axis. In this specification, orthogonal axes parallel to the top and bottom surfaces of the substrate are referred to as the X-axis and the Y-axis. Also, the axis perpendicular to the upper and lower surfaces of the substrate is the Z-axis.

In this specification, terms such as "identical" or "equal" may include cases where there is an error due to manufacturing variations or the like. The error is, for example, within 10%.

FIG. 1 is a diagram showing an example of a magnetic sensor 100 according to one embodiment of the invention. FIG. 1 shows the magnetic sensor 100 in top view. A magnetic sensor 100 includes a substrate 10 and a laminate 20 .

In this example, the magnetic sensor 100 is an MR sensor. Magnetic sensor 100 may be a GMR sensor. Magnetic sensor 100 may be a TMR sensor. Laminated section 20 includes a magnetization free layer 21 , a first non-magnetic layer and a magnetization fixed layer 23 . Although the details will be described later, the direction in which the magnetization of the magnetization fixed layer 23 is fixed is indicated by an arrow (+X-axis direction). Let W be the length of the magnetization free layer 21 in the X-axis direction, and let L be the length of the magnetization free layer 21 in the Y-axis direction. Let WP be the length of the magnetization pinned layer 23 in the X-axis direction, and let LP be the length of the magnetization pinned layer 23 in the Y-axis direction. Let S be the axis of symmetry of the magnetization free layer 21 and G be the position of the center of gravity of the magnetization fixed layer 23 . The center of gravity may be the center of mass when uniformly distributing mass in a substance.

FIG. 2 is an example of a cross-sectional view taken along line X1-X1 in FIG. The X1-X1 cross section is the XZ cross section passing through the laminated portion 20 . In this cross section, the magnetic sensor 100 includes a substrate 10 , a magnetization free layer 21 , a first nonmagnetic layer 22 and a magnetization fixed layer 23 .

A laminated portion 20 is provided on the substrate 10 . The substrate 10 is, for example, a Si substrate, a glass substrate, or the like. From the viewpoint of ensuring insulation with the laminated portion 20, the substrate 10 is preferably a substrate obtained by depositing an insulating film such as SiO ₂ on a Si substrate. At this time, the substrate 10 may be a patterned substrate for the purpose of combining with an integrated circuit (IC) or the like.

In this example, the laminated section 20 includes a magnetization free layer 21 , a first non-magnetic layer 22 and a magnetization fixed layer 23 . In FIG. 2, the magnetization free layer 21 is provided above the substrate 10 . The magnetization free layer 21 may be provided on the upper surface of the substrate 10 . In FIG. 2 , the first nonmagnetic layer 22 is provided above the magnetization free layer 21 . The first nonmagnetic layer 22 may be provided on the upper surface of the magnetization free layer 21 . In FIG. 2 , the magnetization fixed layer 23 is provided above the first nonmagnetic layer 22 . The magnetization fixed layer 23 may be provided on the upper surface of the first nonmagnetic layer 22 . The first non-magnetic layer 22 may be arranged between the magnetization free layer 21 and the magnetization fixed layer 23 in the height direction (Z-axis direction). The height direction may be the stacking direction in which the stacked portions 20 are stacked. The magnetization free layer 21 may be arranged between the substrate 10 and the first non-magnetic layer 22 in the height direction. By arranging the magnetization free layer 21 between the substrate 10 and the first non-magnetic layer 22, the sensitivity of the magnetic sensor 100 can be improved.

In this example, one laminated portion 20 is provided on the substrate 10 . A plurality of laminated sections 20 may be provided on the substrate 10 . A part of the plurality of laminated sections 20 may be shared. As an example, the multiple lamination sections 20 may have a common magnetization free layer 21 . In this case, each of the first nonmagnetic layers 22 of the multiple laminated sections 20 may be separated from the first nonmagnetic layers 22 of the other laminated sections 20 . Further, each magnetization fixed layer 23 of a plurality of laminated sections 20 may be separated from the magnetization fixed layers 23 of other laminated sections 20 . Moreover, the magnetization free layer 21 of the laminated portion 20 may be separated from the magnetization free layer 21 of the other laminated portion 20 . A plurality of laminated sections 20 may be connected in series or in parallel by a wiring section which will be described later.

Each layer of the laminated part 20 is formed by a sputtering method, for example. Each layer of the laminated section 20 may be formed by other known methods. The plurality of laminated sections 20 may be formed by etching each layer of the laminated section 20 using a mask formed by photolithography. Etching is, for example, dry etching or wet etching.

The magnetization free layer 21 is a layer whose magnetization changes according to an external magnetic field. The magnetization free layer 21 includes at least a first ferromagnetic layer 211 , a second nonmagnetic layer 212 and a second ferromagnetic layer 213 . In this example, the magnetization free layer 21 includes a first ferromagnetic layer 211 , a second nonmagnetic layer 212 , a second ferromagnetic layer 213 , a third nonmagnetic layer 214 and a third ferromagnetic layer 215 . In FIG. 2, a first ferromagnetic layer 211 is provided above the substrate 10 . The first ferromagnetic layer 211 may be provided on the top surface of the substrate 10 . In FIG. 2, the second nonmagnetic layer 212 is provided above the first ferromagnetic layer 211 . The second nonmagnetic layer 212 may be provided on the upper surface of the first ferromagnetic layer 211 . In FIG. 2, the second ferromagnetic layer 213 is provided above the second nonmagnetic layer 212 . The second ferromagnetic layer 213 may be provided on the upper surface of the second nonmagnetic layer 212 . In FIG. 2, the third nonmagnetic layer 214 is provided above the second ferromagnetic layer 213 . The third nonmagnetic layer 214 may be provided on the upper surface of the second ferromagnetic layer 213 . In FIG. 2, the third ferromagnetic layer 215 is provided above the third non-magnetic layer 214 . The third ferromagnetic layer 215 may be provided on the upper surface of the third nonmagnetic layer 214 .

The first ferromagnetic layer 211, the second ferromagnetic layer 213 and the third ferromagnetic layer 215 may be materials that are easily magnetized by an external magnetic field. The first ferromagnetic layer 211, the second ferromagnetic layer 213 and the third ferromagnetic layer 215 may be composed of ferromagnetic materials. Examples of ferromagnetic materials used for the first ferromagnetic layer 211, the second ferromagnetic layer 213, and the third ferromagnetic layer 215 include NiFe, CoFeB, CoFeSiB, CoFe, CoFeTaB, and NiFeSiB. The first ferromagnetic layer 211, the second ferromagnetic layer 213, and the third ferromagnetic layer 215 may contain two or more elements selected from Co, Fe, Si, Ta, Ni, and B. Ferromagnetic materials are not limited to these. The first ferromagnetic layer 211, the second ferromagnetic layer 213, and the third ferromagnetic layer 215 are preferably amorphous from the viewpoint of improving flatness. Either or both the first ferromagnetic layer 211, the second ferromagnetic layer 213 and the third ferromagnetic layer 215 may be amorphous. Each thickness of the first ferromagnetic layer 211, the second ferromagnetic layer 213, and the third ferromagnetic layer 215 in the height direction is preferably 10 nm or more and 300 nm or less. The thickness of each of the first ferromagnetic layer 211, the second ferromagnetic layer 213 and the third ferromagnetic layer 215 in the height direction is greater than the thickness of each of the second nonmagnetic layer 212 and the third nonmagnetic layer 214. good.

The second nonmagnetic layer 212 and the third nonmagnetic layer 214 may be made of nonmagnetic material. Examples of non-magnetic materials include Ru, Ta, TaB, and the like. Nonmagnetic materials used for the second nonmagnetic layer 212 and the third nonmagnetic layer 214 are not limited to these. If the thickness of each of the second nonmagnetic layer 212 and the third nonmagnetic layer 214 in the height direction is less than 2 nm, magnetostatic coupling, which will be described later, is weakened. Magnetostatic coupling is also weakened when the thickness of each of the second nonmagnetic layer 212 and the third nonmagnetic layer 214 in the height direction is greater than 100 nm. Therefore, the thickness of each of the second nonmagnetic layer 212 and the third nonmagnetic layer 214 in the height direction is preferably 2 nm or more and 100 nm or less.

The first nonmagnetic layer 22 may be made of a nonmagnetic material. If the magnetic sensor 100 is a GMR sensor, the non-magnetic material may be a metallic material such as Cu. If the magnetic sensor 100 is a TMR sensor, _the non-magnetic material may be an insulating material such as _Al2O3 , MgO. The first non-magnetic layer 22 may contain Mg and O. For high magnetic sensitivity, it is preferable to use MgO as the non-magnetic material. The thickness of the first nonmagnetic layer 22 in the height direction is preferably 0.3 nm or more and 10 nm or less.

The magnetization fixed layer 23 is mainly made of a ferromagnetic material so that the magnetization direction is not easily changed by an external magnetic field. The magnetization fixed layer 23 has its magnetization fixed in the first direction (+X-axis direction). The magnetization fixed layer 23 may be composed of a single material, or may be composed of laminated materials. As an example, the magnetization fixed layer 23 has a structure in which a ferromagnetic material is pinned with an antiferromagnetic material. Examples of the ferromagnetic material used for the magnetization fixed layer 23 are NiFe, CoFeB, CoFeSiB, CoFe, and the like. Ferromagnetic materials are not limited to these. Examples of the antiferromagnetic material used for the magnetization fixed layer 23 include IrMN and PtMn. A nonmagnetic layer such as Ru, Ta, TaB, or the like may be inserted in the magnetization fixed layer 23 . The thickness of the magnetization fixed layer 23 in the height direction is preferably 5 nm or more and 100 nm or less.

A non-magnetic cap layer is preferably provided above the laminated portion 20 . Laminated portion 20 may include a cap layer. The cap layer may be provided on top of the stack 20 . By providing the cap layer, it is possible to prevent oxidation of the upper portion of the stacked portion 20 . From the viewpoint of connection with the wiring portion, the cap layer is preferably made of a conductive material such as Au, Ru, or Ta.

A buffer layer is preferably provided between the laminated portion 20 and the substrate 10 . The laminate section 20 may include a buffer layer. The buffer layer may be provided at the bottom of the stack 20 . By providing the buffer layer, the adhesion between the stacked portion 20 and the substrate 10 can be improved. Materials for the buffer layer are, for example, materials such as Ru, Ta, and TaB. Materials for the buffer layer are not limited to these.

FIG. 3 is a diagram for explaining the outline of the magnetic sensor 100. As shown in FIG. In the magnetic sensor 100 of FIG. 3, the first nonmagnetic layer 22, the third nonmagnetic layer 214, and the third ferromagnetic layer 215 are omitted for explanation. Let H be the external magnetic field in FIG.

The magnetization free layer 21 has a structure that can be freely rotated with respect to the external magnetic field H. As shown in FIG. Therefore, when an external magnetic field H is applied and the relative angle between the magnetization direction of the magnetization free layer 21 and the magnetization direction of the magnetization fixed layer 23 changes, the current flowing through the first non-magnetic layer 22 changes, so that the magnetic field can be detected. can.

In this example, the magnetization free layer 21 includes a first ferromagnetic layer 211 , a second nonmagnetic layer 212 and a second ferromagnetic layer 213 . The second nonmagnetic layer 212 is sandwiched between the first ferromagnetic layer 211 and the second ferromagnetic layer 213 in the height direction. The first ferromagnetic layer 211 and the second ferromagnetic layer 213 may be separated in the height direction by the second non-magnetic layer 212 . Therefore, the first ferromagnetic layer 211 and the second ferromagnetic layer 213 are magnetostatically coupled. In FIG. 3, the magnetostatic coupling is indicated by dotted arrows. Magnetostatic coupling of the first ferromagnetic layer 211 and the second ferromagnetic layer 213 converts the first ferromagnetic layer 211 and the second ferromagnetic layer 213 into a single magnetic domain, thereby suppressing noise such as Barkhausen noise. can be done.

A demagnetizing field is generated in the magnetization free layer 21 by the magnetic field H. FIG. A demagnetizing field is a magnetic field in the opposite direction to the magnetic field H. The magnitude of the demagnetizing field changes depending on the shape of the magnetization free layer 21 . The magnetostatic coupling of the magnetization free layer 21 may be affected by the demagnetizing field. Therefore, the linearity of the MR curve of the magnetic sensor 100 may deteriorate. Therefore, the measurement accuracy of the magnetic sensor 100 deteriorates.

A magnetic flux is generated between the magnetization free layer 21 and the magnetization fixed layer 23 . The magnetic flux is indicated by a dashed-dotted arrow. The magnetization free layer 21 and the magnetization fixed layer 23 are magnetostatically interacting with each other. The magnetic flux flowing parallel to the X-axis direction from the side surface of the magnetization fixed layer 23 flows into the magnetization free layer 21 from the side surface of the magnetization free layer 21 . Magnetostatic interaction between the magnetization free layer 21 and the magnetization fixed layer 23 may deteriorate the linearity of the MR curve and deteriorate the measurement accuracy of the magnetic sensor 100 .

In the magnetic sensor 100 of this example, the length W of the magnetization free layer 21 in the first direction and the length W of the magnetization free layer 21 in the second direction (Y-axis direction) perpendicular to the first direction when viewed from above L satisfies W/L>1 (see FIG. 1). By setting W/L>1, the magnitude of the demagnetizing field generated in the magnetization free layer 21 can be reduced. Therefore, the linearity of the MR curve of the magnetic sensor 100 can be improved, and the measurement accuracy of the magnetic sensor 100 can be improved. The length W of the magnetization free layer 21 in the first direction may be 1 mm or less. The length L of the magnetization free layer 21 in the second direction may be 1 mm or less.

The length W of the magnetization free layer 21 in the first direction and the length L of the magnetization free layer 21 in the second direction in top view may satisfy W/L<50. By satisfying W/L<50, the length W of the magnetization free layer 21 in the first direction can be prevented from increasing, and the magnetic sensor 100 can be miniaturized. In addition, it is possible to prevent stress caused by an increase in W/L. The length W of the magnetization free layer 21 in the first direction and the length L of the magnetization free layer 21 in the second direction in top view may satisfy W/L<30. The length W of the magnetization free layer 21 in the first direction and the length L of the magnetization free layer 21 in the second direction in top view may satisfy W/L<20.

In FIG. 1, the magnetization free layer 21 has an axisymmetric shape with an axis of symmetry S parallel to the second direction when viewed from above. Further, in FIG. 1, the position G of the center of gravity of the magnetization fixed layer 23 may be arranged at a position overlapping the axis of symmetry S when viewed from above. The center of gravity of the magnetization free layer 21 may be located at the position G of the center of gravity of the magnetization fixed layer 23 . By having such a configuration, the sensitivity of the magnetic sensor 100 can be improved.

In FIG. 1, the length WP of the magnetization fixed layer 23 in the first direction (X-axis direction) and the length WP of the magnetization fixed layer 23 in the second direction (Y-axis direction) perpendicular to the first direction when viewed from the top. LP satisfies WP/LP>1. The magnetization fixed layer 23 has a longitudinal direction with respect to the magnetization direction of the magnetization fixed layer 23 . By having such a configuration, the measurement accuracy of the magnetic sensor 100 can be improved.

FIG. 4 is a diagram showing an example of a magnetic sensor 200 according to another embodiment. The magnetic sensor 200 in FIG. 4 is different from the magnetic sensor 100 in FIG. 1 in the shape of the laminated portion 20 when viewed from above. Other configurations of the magnetic sensor 200 of FIG. 4 may be the same as those of the magnetic sensor 100 of FIG.

In the magnetic sensor 200 of this example, the minimum distance D in the first direction (X-axis direction) between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 satisfies D>45 μm. The outer edge 26 of the magnetization free layer 21 is the outer peripheral portion of the magnetization free layer 21 . The outer edge 28 of the magnetization fixed layer 23 is the outer peripheral portion of the magnetization fixed layer 23 . By satisfying D>45 μm, the effect of magnetostatic interaction between the magnetization free layer 21 and the magnetization fixed layer 23 can be reduced. Therefore, the linearity of the MR curve of the magnetic sensor 200 can be improved, and the measurement accuracy of the magnetic sensor 100 can be improved.

A minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 may satisfy D<1 mm (1000 μm). By satisfying D<1 mm, the distance D can be prevented from becoming large, and the size of the magnetic sensor 200 can be reduced. A minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 may satisfy D<0.5 mm (500 μm). A minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 may satisfy D<0.3 mm (300 μm).

The minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 and the length WP of the magnetization fixed layer 23 in the first direction satisfy D>WP. is preferred. By satisfying D>WP, the magnetic flux flowing from the magnetization fixed layer 23 to the magnetization free layer 21 can be reduced, the linearity of the MR curve of the magnetic sensor 200 can be improved, and the measurement accuracy of the magnetic sensor 100 can be improved. .

FIG. 5 is a diagram showing an example of a magnetic sensor 300 according to another embodiment. A magnetic sensor 300 in FIG. 5 differs from the magnetic sensor 100 in FIG. 1 in that a plurality of magnetization fixed layers 23 are provided in the magnetization free layer 21 . Further, in the magnetic sensor 300 of FIG. 5, a plurality of first nonmagnetic layers 22 (see FIG. 6) are provided in the magnetization free layer 21 . In FIG. 5, the description of the reference numerals common to those in FIG. 1 is omitted. In FIG. 5, the position of the center of gravity of the magnetization fixed layer 23 provided on the positive side in the Y-axis direction is assumed to be G1, and the position of the center of gravity of the magnetization fixed layer 23 provided on the negative side in the Y-axis direction is assumed to be G2.

FIG. 6 is an example of a cross-sectional view along Y3-Y3 in FIG. A Y3-Y3 cross section is a YZ cross section passing through the plurality of first non-magnetic layers 22 and the plurality of magnetization fixed layers 23 . In this cross section, the magnetic sensor 300 comprises a substrate 10 , a magnetization free layer 21 , two first non-magnetic layers 22 and two magnetization fixed layers 23 .

In this example, one magnetization free layer 21 is provided with a plurality of first nonmagnetic layers 22 and a plurality of magnetization fixed layers 23 . In FIG. 6 , a plurality of fixed magnetization layers 23 are arranged on one surface side (upper surface side) of the magnetization free layer 21 . The plurality of magnetization fixed layers 23 are arranged along the second direction (Y-axis direction). In this case, a plurality of laminated parts 20 may be provided on the substrate 10 . A plurality of laminated sections 20 have a common magnetization free layer 21 . In this example, each first nonmagnetic layer 22 is separated from other first nonmagnetic layers 22 . Also, in this example, each magnetization fixed layer 23 is separated from the other magnetization fixed layers 23 . Each of the multiple laminated sections 20 may function as an electrode.

In FIG. 5, the magnetization free layer 21 has an axisymmetric shape with an axis of symmetry S parallel to the second direction when viewed from above. In FIG. 5, the positions G1 and G2 of the center of gravity of the magnetization fixed layer 23 may be arranged at positions overlapping the axis of symmetry S when viewed from above. By having such a configuration, the sensitivity of the magnetic sensor 300 can be improved.

FIG. 7 is a diagram showing an example of a magnetic sensor 400 according to another embodiment. A magnetic sensor 400 in FIG. 7 is different from the magnetic sensor 100 in FIG. 1 in that it includes a protective layer (see FIG. 8) and a wiring portion 40 . In FIG. 7, the description of the reference numerals common to those in FIG. 1 is omitted. In FIG. 7, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

FIG. 8 is an example of a cross-sectional view along Y4-Y4 in FIG. A Y4-Y4 cross section is a YZ cross section passing through the plurality of first non-magnetic layers 22 and the plurality of magnetization fixed layers 23 . In the cross section, the magnetic sensor 400 includes a substrate 10 , a magnetization free layer 21 , four first nonmagnetic layers 22 , four magnetization fixed layers 23 , a protective layer 30 and a wiring section 40 .

In this example, the substrate 10 is provided with a plurality of magnetization free layers 21 . In FIG. 8, the substrate 10 is provided with two magnetization free layers 21 . A plurality of first nonmagnetic layers 22 and a plurality of magnetization fixed layers 23 are provided in each magnetization free layer 21 . In FIG. 8, each magnetization free layer 21 is provided with two first nonmagnetic layers 22 and two magnetization fixed layers 23 .

The protective layer 30 is provided to maintain insulation between the laminated portion 20 and the wiring portion 40 . The protective layer 30 is not limited as long as it can maintain insulation between the laminated portion 20 and the wiring portion 40 . The protective layer 30 is, for example, silicon oxide or silicon nitride. The protective layer 30 may be provided with an opening 62 (conducting window) that connects the laminated portion 20 and the wiring portion 40 .

The wiring portion 40 electrically connects the laminated portion 20 and an external electrode (not shown). Also, the wiring portion 40 electrically connects the plurality of laminated portions 20 . The material of the wiring part 40 is, for example, a conductive material such as Au, Cu, Cr, Ni, Al, Ta, Ru. The material of the wiring part 40 is not limited to these examples. The wiring part 40 may be made of a single material. The wiring part 40 may be a mixture or lamination of multiple materials. The wiring part 40 may be formed by a known method. By providing the wiring portion 40, the current flows as indicated by the arrows in FIG. A current flows in each stack 20 in the height direction.

FIG. 9 is a diagram showing an example of a magnetic sensor 500 according to another embodiment. A magnetic sensor 500 in FIG. 9 differs from the magnetic sensor 300 in FIG. 5 in that it includes a magnetic concentrator 60 . In FIG. 9, the description of the reference numerals common to those in FIG. 5 is omitted.

FIG. 10 is an example of a cross-sectional view taken along line X5-X5 of FIG. The X5-X5 cross section is the XZ cross section passing through the magnetic concentrator 60 . In this section, the magnetic sensor 500 includes a substrate 10 , a magnetization free layer 21 , a first nonmagnetic layer 22 , a magnetization fixed layer 23 , a protective layer 30 and two magnetic concentrators 60 .

The magnetic concentrator 60 amplifies the introduced magnetization. The magnetization of the magnetization free layer 21 can be amplified by the magnetic concentrator 60 to increase the sensitivity of the magnetic sensor 500 . The magnetic concentrator 60 may be electrically insulated from the magnetization free layer 21 , the first non-magnetic layer 22 and the magnetization fixed layer 23 . The magnetic concentrator 60 may be made of a ferromagnetic material. Examples of ferromagnetic materials used for the magnetic flux concentrator 60 include NiFe, CoFeB, CoFeSiB, CoFeTaB, NiFeCuMo, and CoZrNb. Examples of the ferromagnetic material used for the magnetic concentrator 60 are not limited to these. The magnetic concentrator 60 may be formed by a known method such as plating or sputtering. When forming the magnetic flux concentrator 60 by plating, it is preferable to form a seed layer of Ta, Ti, or the like, and then form a film of Cu, NiFe, or the like. By forming the seed layer, the adhesion between the magnetic concentrator 60 and the protective layer 30 can be improved.

In this example, the magnetic sensor 500 includes two magnetic concentrators 60 . The two magnetic concentrators 60 may be provided so as to sandwich the laminated section 20 . At least part of the magnetization free layer 21 may overlap the magnetic concentrator 60 in the first direction (X-axis direction). At least part of the first non-magnetic layer 22 may overlap the magnetic concentrator 60 in the first direction. At least part of the magnetization fixed layer 23 may overlap the magnetic concentrator 60 in the first direction.

FIG. 11 is a diagram showing an example of a magnetic sensor 600 according to another embodiment. A magnetic sensor 600 in FIG. 11 differs from the magnetic sensor 500 in FIG. 9 in the configuration of the magnetic concentrator 60 . In FIG. 11, the description of the reference numerals common to those in FIG. 9 is omitted. In FIG. 11, the arrangement of the magnetization free layer 21 overlapping with the magnetic flux concentrating portion 60 and the wiring portion 40 overlapping with the magnetic flux concentrating portion 60 are indicated by dotted lines. Also, in FIG. 11, the arrangement of the magnetization fixed layer 23 overlapping the wiring portion 40 is indicated by a dotted line.

In this example, at least part of the magnetic concentrator 60 overlaps with at least part of the magnetization free layer 21 when viewed from above. A half or more region of the magnetization free layer 21 in top view may overlap with the magnetic flux concentrator 60 . Since the magnetic concentrator 60 has a region that overlaps the magnetization free layer 21 when viewed from above, the linearity of the MR curve of the magnetic sensor 600 can be improved, and the measurement accuracy of the magnetic sensor 600 can be improved.

FIG. 12 is an example of a cross-sectional view taken along line X6-X6 of FIG. The X6-X6 cross section is the XZ cross section passing through the magnetic concentrator 60 . In this cross section, the magnetic sensor 600 includes a substrate 10 , a magnetization free layer 21 , a first nonmagnetic layer 22 , a magnetization fixed layer 23 , a protective layer 30 and two magnetic concentrators 60 .

The two magnetic concentrators 60 may be provided so as to sandwich the laminated section 20 . At least part of the magnetization free layer 21 does not have to overlap the magnetic concentrator 60 in the first direction (X-axis direction). At least part of the first non-magnetic layer 22 may overlap the magnetic concentrator 60 in the first direction. At least part of the magnetization fixed layer 23 may overlap the magnetic concentrator 60 in the first direction.

FIG. 13 is another example of the X6-X6 cross-sectional view of FIG. The X6-X6 cross section is the XZ cross section passing through the magnetic concentrator 60 . In this cross section, the magnetic sensor 600 includes a substrate 10 , a magnetization free layer 21 , a first nonmagnetic layer 22 , a magnetization fixed layer 23 , a protective layer 30 and two magnetic concentrators 60 .

FIG. 13 differs from FIG. 12 in that at least part of the magnetization free layer 21 overlaps the magnetic concentrator 60 in the first direction (X-axis direction). At least part of the side surface 25 of the magnetization free layer 21 may overlap the magnetic concentrator 60 in the first direction. Since at least a portion of the magnetization free layer 21 overlaps the magnetic concentrator 60 in the first direction, the sensitivity of the magnetic sensor 600 can be enhanced.

FIG. 14 is a diagram showing an example of a magnetic sensor 700 according to another embodiment. A magnetic sensor 700 in FIG. 14 differs from the magnetic sensor 100 in FIG. 2 in the shape of the magnetization free layer 21 . Other configurations of the magnetic sensor 700 of FIG. 14 may be the same as those of the magnetic sensor 100 of FIG.

In this example, the thickness T1 of the side surface 25 of the magnetization free layer 21 is smaller than the thickness T2 of the region of the magnetization free layer 21 overlapping the magnetization fixed layer 23 in top view. The magnetization free layer 21 may have a tapered shape on the side surface 25 . By reducing the thickness T1 of the side surface 25 of the magnetization free layer 21, the effect of magnetostatic interaction between the magnetization free layer 21 and the magnetization fixed layer 23 can be reduced. Therefore, the linearity of the MR curve of the magnetic sensor 200 can be improved, and the measurement accuracy of the magnetic sensor 100 can be improved.

FIG. 15 is a diagram showing an example of a magnetic sensor 800 according to another embodiment. A magnetic sensor 800 in FIG. 15 differs from the magnetic sensor 300 in FIG. 5 in the shape of the magnetization fixed layer 23 . In FIG. 15, the description of the reference numerals common to those in FIG. 5 is omitted.

In the magnetic sensor 800 of this example, the length WP of the magnetization fixed layer 23 in the first direction (X-axis direction) and the magnetization fixed direction (Y-axis direction) in the second direction (Y-axis direction) perpendicular to the first direction when viewed from above The length LP of layer 23 satisfies WP/LP<1. The magnetization fixed layer 23 has a longitudinal direction in a direction (second direction) perpendicular to the magnetization direction of the magnetization fixed layer 23 . Also, in this example, the two magnetization fixed layers 23 are arranged along the second direction. In this example, the condition of D>45 μm can be easily satisfied, the linearity of the MR curve of the magnetic sensor 600 can be improved, and the measurement accuracy of the magnetic sensor 600 can be improved.

In the magnetic sensors 300 to 800 shown in FIGS. 5 to 15, the length W of the magnetization free layer 21 in the first direction and the magnetization free layer in the second direction perpendicular to the first direction when viewed from above The length L of 21 may satisfy W/L>1. By setting W/L>1, the linearity of the MR curve of the magnetic sensor can be improved, and the measurement accuracy of the magnetic sensor can be improved. 5 to 15, the minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 is D>45 μm. may be satisfied. By setting D>45 μm, the linearity of the MR curve of the magnetic sensor can be improved, and the measurement accuracy of the magnetic sensor can be improved.

FIG. 16 is a diagram illustrating an example of a flowchart of a method for manufacturing the magnetic sensor 400. As shown in FIG. The manufacturing method of the magnetic sensor 400 includes a layered portion forming step S101, a layered portion processing step S102, a magnetization fixed layer processing step S103, and a wiring portion forming step S104. The method for manufacturing other magnetic sensors may be the same.

FIG. 17 is a diagram for explaining the step S101 of forming the laminated portion. In the layered portion forming step S101, the layered portion 20 is formed. The laminated portion 20 may be formed by a known method such as magnetron sputtering. Also, in the layered portion forming step S101, the mask member 50 is formed above the layered portion 20. As shown in FIG. The mask member 50 may be formed by photolithography or the like. The mask member 50 may be formed in a desired shape at a desired location above the laminated portion 20 .

FIG. 18 is a diagram for explaining the laminated portion processing step S102. In the laminated portion processing step S102, the laminated portion 20 is processed. In this example, the laminated portion 20 is etched and separated by a known method such as dry etching. In the laminated portion processing step S102, a plurality of laminated portions 20 are formed. After processing the laminated portion 20, the mask member 50 is removed by a known method.

FIG. 19 is a diagram for explaining the magnetization fixed layer processing step S103. In the magnetization fixed layer processing step S103, the first non-magnetic layer 22 and the magnetization fixed layer 23 are processed. In the magnetization fixed layer processing step S<b>103 , a mask member 51 is formed above the magnetization fixed layer 23 . The mask member 51 may be formed by a known method such as photolithography. In this example, the magnetization fixed layer 23 is etched and separated by a known method such as dry etching. For example, the magnetization pinned layer 23 is separated using an ECR plasma etching apparatus. At this time, part or all of the first non-magnetic layer 22 not covered with the mask member 51 may be etched. A portion of the magnetization free layer 21 not covered with the mask member 51 may be etched. A plurality of magnetization fixed layers 23 may be formed above the magnetization free layer 21 . After processing the magnetization fixed layer 23, the mask member 51 is removed by a known method.

FIG. 20 is a diagram for explaining the wiring portion forming step S104. In the wiring portion forming step S104, a protective layer 30 is formed as an insulating film. The protective layer 30 may be formed by a known method such as the PCVD method. The protective layer 30 is provided with openings 62 (conducting windows). A mask member (not shown) formed by a known method such as photolithography may be formed on the protective layer 30 . After forming the mask member, the protective layer 30 may be etched by a known method such as dry etching to form the opening 62 . The protective layer 30 is etched using, for example, an RIE etching apparatus. After processing the protective layer 30, the mask member used for dry etching of the protective layer 30 is removed by a known method.

In the wiring part forming step S104, after the opening part 62 is formed, the mask member 53 is formed. The mask member 53 may be formed by a known method such as photolithography. A mask member 53 may be formed above the protective layer 30 . The mask member 53 may expose regions where the wiring portions 40 and electrodes are to be formed, and may cover other regions. After forming the mask member 53, a conductive film is formed. The conductive film is formed using, for example, a magnetron sputtering apparatus. The mask member 53 is removed by a known method such as the lift-off method, and the wiring portion 40 is formed as shown in FIG. A heat treatment may be performed after the wiring portion forming step S104.

FIG. 21 is a diagram showing a magnetic sensor 1100 according to an example. A magnetic sensor 1100 in FIG. 21 includes a substrate 10, a magnetization free layer 21, a magnetization fixed layer 23, and a wiring portion 40 in top view, similarly to the magnetic sensor 400 in FIG. The magnetic sensor 1100 in FIG. 21 may have a shape different from that of the magnetic sensor 400 in FIG. 7 when viewed from above. In FIG. 21, the description of the reference numerals common to those in FIG. 7 is omitted. In FIG. 21, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

The magnetic sensor 1100 may be manufactured through a stack forming step S101, a stack processing step S102, a magnetization fixed layer processing step S103, and a wiring portion forming step S104 shown in FIG. The manufacturing method of the magnetic sensor 1100 may include a layered portion forming step S101, a layered portion processing step S102, a magnetization fixed layer processing step S103, and a wiring portion forming step S104. The method of manufacturing the magnetic sensor 1100 may also include a heat treatment step. During the heat treatment stage, the magnetic sensor 1100 may be heat treated. The magnetic sensor 1100 may be heat treated by a magnetic field heat treatment apparatus. For example, the magnetic sensor 1100 is heat-treated at 325° C. for 50 minutes while applying a magnetic field in the second direction (first heat treatment), and then heat-treated at 225° C. for 50 minutes while applying a magnetic field in the first direction (second heat treatment). ) is implemented. The heat treatment method is not limited to this.

In the magnetic sensor 1100 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 600 μm. The length L of the magnetization free layer 21 in the second direction (Y-axis direction) perpendicular to the first direction in top view is 100 μm. Therefore, W/L=6.

FIG. 22 is a diagram showing a magnetic sensor 1200 according to an example. A magnetic sensor 1200 in FIG. 22 includes a substrate 10, a magnetization free layer 21, a magnetization fixed layer 23, and a wiring portion 40 in top view, similarly to the magnetic sensor 1100 in FIG. The magnetic sensor 1200 in FIG. 22 may be different in shape from the top view of the magnetic sensor 1100 in FIG. In FIG. 22, the description of the symbols common to those in FIG. 21 is omitted. In FIG. 22, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

In the magnetic sensor 1200 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 200 μm. The length WP of the magnetization fixed layer 23 in the first direction is 42 μm. Therefore, the minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 is 79 μm.

FIG. 23 is a diagram showing a magnetic sensor 1300 according to an example. A magnetic sensor 1300 in FIG. 23 includes a substrate 10, a magnetization free layer 21, a magnetization fixed layer 23, a wiring portion 40, and a magnetic concentrator 60 in top view, similarly to the magnetic sensor 600 in FIG. In FIG. 23, the description of the reference numerals common to those in FIG. 11 is omitted. In FIG. 23, the arrangement of the magnetization free layer 21 overlapping with the magnetic flux concentrating portion 60 and the wiring portion 40 overlapping with the magnetic flux concentrating portion 60 are indicated by dotted lines. Also, in FIG. 23, the arrangement of the magnetization fixed layer 23 overlapping the wiring portion 40 is indicated by a dotted line.

In the magnetic sensor 1300 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 200 μm. The length WP of the magnetization fixed layer 23 in the first direction is 42 μm. Therefore, the minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 is 79 μm. Note that in FIG. 23, the width D1 where the magnetization free layer 21 overlaps with one magnetic converging portion 60 in the first direction is 75 μm.

FIG. 24 is a diagram showing a magnetic sensor 1400 according to a comparative example. A magnetic sensor 1400 in FIG. 24 includes a substrate 10, a magnetization free layer 21, a magnetization fixed layer 23, and a wiring portion 40 in top view, similarly to the magnetic sensor 1100 in FIG. The magnetic sensor 1400 in FIG. 24 may have a shape different from that of the magnetic sensor 1100 in FIG. 21 when viewed from above. In FIG. 24, the description of the symbols common to those in FIG. 21 is omitted. In FIG. 24, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

In the magnetic sensor 1400 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 100 μm. The length L of the magnetization free layer 21 in the second direction (Y-axis direction) perpendicular to the first direction in top view is 140 μm. Therefore, W/L is about 0.71.

FIG. 25 is a diagram showing a magnetic sensor 1500 according to a comparative example. A magnetic sensor 1500 in FIG. 25 includes a substrate 10, a magnetization free layer 21, a magnetization fixed layer 23, and a wiring portion 40 in top view, similarly to the magnetic sensor 1200 in FIG. The magnetic sensor 1500 in FIG. 25 may differ from the magnetic sensor 1200 in FIG. 22 in top view shape. In FIG. 25, the description of the symbols common to those in FIG. 22 is omitted. In FIG. 25, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

In the magnetic sensor 1500 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 100 μm. The length WP of the magnetization fixed layer 23 in the first direction is 42 μm. Therefore, the minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 is 29 μm.

FIG. 26 is a diagram showing a magnetic sensor 1600 according to a comparative example. A magnetic sensor 1600 in FIG. 26 differs from the magnetic sensor 1300 in FIG. 23 in that the magnetic concentrator 60 is not provided. In FIG. 26, the description of the reference numerals common to those in FIG. 23 is omitted. In FIG. 26, the arrangement of the magnetization fixed layer 23 that overlaps the wiring portion 40 is indicated by a dotted line.

In the magnetic sensor 1600 of this example, the length W of the magnetization free layer 21 in the first direction (X-axis direction) is 200 μm. The length WP of the magnetization fixed layer 23 in the first direction is 42 μm. Therefore, the minimum distance D in the first direction between the outer edge 26 of the magnetization free layer 21 and the outer edge 28 of the magnetization fixed layer 23 is 79 μm.

FIG. 27 is a diagram showing MR curves of the magnetic sensor 1100 and the magnetic sensor 1400. FIG. The MR curve was measured by changing the external magnetic field from +200 Oe to -200 Oe from the first direction while applying a voltage of 100 mV to the magnetic sensor.

According to FIG. 27, the magnetic sensor 1400 oscillates the MR curve irregularly, while the magnetic sensor 1100 suppresses the MR curve oscillation. The linearity value ( ^R2 value) of the MR curve of the magnetic sensor 1100 was 0.995. On the other hand, the linearity value ( ^R2 value) of the MR curve of the magnetic sensor 1500 was 0.823.

FIG. 28 is a diagram showing MR curves of the magnetic sensor 1200 and the magnetic sensor 1500. FIG. The MR curve was measured by changing the external magnetic field from +200 Oe to -200 Oe from the first direction while applying a voltage of 100 mV to the magnetic sensor, as in FIG.

According to FIG. 28, the MR curve of the magnetic sensor 1500 oscillates irregularly, but the MR curve of the magnetic sensor 1200 is suppressed from oscillating. The linearity value ( ^R2 value) of the MR curve of the magnetic sensor 1200 was 0.985. On the other hand, the linearity value ( ^R2 value) of the MR curve of the magnetic sensor 1500 was 0.874.

FIG. 29 is a table summarizing the linearity of the MR curves of the magnetic sensors 1100 to 1600. In FIG. Each MR curve was measured by changing the external magnetic field from +200 Oe to -200 Oe from the first direction while applying a voltage of 100 mV to the magnetic sensor. The magnetic sensor 1100 and the magnetic sensor 1200 of the example have improved linearity compared to the magnetic sensor 1400 and the magnetic sensor 1500 of the comparative example. Further, the magnetic sensor 1300 of the example has improved linearity compared to the magnetic sensor 1600 of the comparative example, and the linearity is improved because the magnetic flux concentrator 60 overlaps the magnetization free layer 21 when viewed from above. I understand.

FIG. 30 is a list of magnetic sensors created for investigating the linearity of MR curves. In FIG. 30, t is the film thickness of the first ferromagnetic layer 211 and the second ferromagnetic layer 213 in the height direction. A magnetic sensor whose shape was changed was produced, and the linearity of the MR curve was investigated.

FIG. 31 is a diagram showing the relationship between W/L and the linearity value of the MR curve. It can be seen from FIG. 31 that the linearity value of the MR curve is greater than 0.95 when W/L>1, with W/L being 1 as a change point. Further, it can be seen that the value of linearity of the MR curve becomes larger than 0.98 when W/L>1.43, with W/L being 1.43 as a change point. Therefore, it is preferable to set W/L>1.43.

FIG. 32 is a diagram showing the relationship between D and the linearity value of the MR curve. According to FIG. 32, when D<45 μm, magnetic sensors with MR curve linearity values below 0.95 are irregularly present. On the other hand, it can be seen that the linearity value of the MR curve is stably above 0.95 when D>45 μm. Furthermore, it can be seen that the linearity value of the MR curve is stably above 0.97 when D>170 μm. Therefore, it is preferable to set D>170 μm.

FIG. 33 is a diagram showing the relationship between the LP and linearity values of the MR curve. It can be seen that the linearity value of the MR curve is greater than 0.94 when LP<125 μm. Therefore, it is preferable to set LP<125 μm. It can also be seen that the linearity value of the MR curve is greater than 0.97 when LP<51 μm. Therefore, it is more preferable to set LP<51 μm.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the scope of claims that forms with such modifications or improvements can also be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 10... Substrate, 20... Laminated part, 21... Magnetization free layer, 22... First non-magnetic layer, 23... Magnetization fixed layer, 25... Side surface, 26... Outer edge, 28... Outer edge, 30 Protective layer 40 Wiring portion 50 Mask member 51 Mask member 53 Mask member 60 Magnetic converging portion 62 Opening 211 First ferromagnetic layer , 212... Second non-magnetic layer 213... Second ferromagnetic layer 214... Third non-magnetic layer 215... Third ferromagnetic layer 100... Magnetic sensor 200... Magnetic sensor , 300... magnetic sensor, 400... magnetic sensor, 500... magnetic sensor, 600... magnetic sensor, 700... magnetic sensor, 800... magnetic sensor, 1100... magnetic sensor, 1200... magnetic sensor, 1300 Magnetic sensor 1400 Magnetic sensor 1500 Magnetic sensor 1600 Magnetic sensor

Claims (17)

a substrate;
a laminate provided on the substrate; and
The laminated portion is
a magnetization free layer;
a magnetization fixed layer whose magnetization is fixed in a first direction;
a first non-magnetic layer disposed between the magnetization free layer and the magnetization fixed layer;
The magnetization free layer is
a second non-magnetic layer;
a first ferromagnetic layer and a second ferromagnetic layer separated in the height direction by the second nonmagnetic layer;
The length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction perpendicular to the first direction when viewed from the top are magnetic fields satisfying W/L>1. sensor. 2. The magnetic sensor according to claim 1, wherein the length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction satisfy W/L>1.43. 3. The magnetic sensor according to claim 1, wherein the length W of the magnetization free layer in the first direction and the length L of the magnetization free layer in the second direction satisfy W/L<50. 4. The magnetic sensor according to any one of claims 1 to 3, wherein a minimum distance D in the first direction between an outer edge of the magnetization free layer and an outer edge of the magnetization fixed layer satisfies D>45 μm. 5. The magnetic sensor according to claim 4, wherein a minimum distance D in the first direction between the outer edge of the magnetization free layer and the outer edge of the magnetization fixed layer satisfies D<1 mm. The magnetic sensor according to any one of claims 1 to 5, wherein the magnetization free layer is arranged between the substrate and the first nonmagnetic layer. The magnetization free layer has a line-symmetrical shape with an axis of symmetry parallel to the second direction when viewed from above,
The magnetic sensor according to any one of claims 1 to 6, wherein the center of gravity of the magnetization fixed layer is arranged at a position overlapping with the axis of symmetry when viewed from above. The magnetic sensor according to any one of claims 1 to 7, wherein a plurality of the magnetization fixed layers are arranged on one surface side of the magnetization free layer. The magnetic sensor according to claim 8, wherein the plurality of magnetization fixed layers are arranged along the second direction. 10. The magnetic sensor according to any one of claims 1 to 9, wherein both or either of the first ferromagnetic layer and the second ferromagnetic layer are amorphous. The magnetic sensor according to any one of claims 1 to 10, further comprising a magnetic concentrator electrically insulated from the magnetization free layer, the magnetization fixed layer and the first non-magnetic layer. 12. The magnetic sensor according to claim 11, wherein at least a portion of the magnetic flux concentrator overlaps with at least a portion of the magnetization free layer when viewed from above. The magnetic sensor according to claim 11 or 12, wherein at least part of a side surface of the magnetization free layer overlaps the magnetic concentrator in the first direction. The magnetic sensor according to any one of claims 1 to 13, wherein the magnetization fixed layer has a length LP in the second direction smaller than 125 µm. A minimum distance D in the first direction between an outer edge of the magnetization free layer and an outer edge of the magnetization fixed layer and a length WP of the magnetization fixed layer in the first direction satisfy D>WP. Item 15. The magnetic sensor according to any one of Items 1 to 14. The magnetic sensor according to any one of claims 1 to 15, wherein the length W of the magnetization free layer in the first direction is 1 mm or less. The magnetic sensor according to any one of claims 1 to 16, wherein the thickness of the side surface of the magnetization free layer is smaller than the thickness of the region of the magnetization free layer that overlaps with the magnetization fixed layer when viewed from above.

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