Magnetic sensor and method for manufacturing a magnetic sensor

Abstract

To provide a magnetic sensor that can improve detection accuracy. [Solution] The magnetic sensor 1 comprises a substrate 10, a magnetic film 11, an inorganic protective film 12, and an organic protective part 13. The magnetic film 11 is arranged on the main surface 10a of the substrate 10. The inorganic protective film 12 is arranged to cover the first surface 11a, which is the surface of the magnetic film 11 opposite to the substrate 10, and has contact holes 12c formed therein for passing through the extraction wiring 14 that is electrically connected to the magnetic film 11. The organic protective part 13 is arranged to cover a contact portion 12p, which is a part of the second surface 12a, which is the surface of the inorganic protective film 12 opposite to the magnetic film 11, including the area corresponding to the contact holes 12c. The ratio of the contact portion 12p on the second surface 12a to which the organic protective part 13 is arranged is such that the change in the properties of the magnetic film 11 is within a predetermined range.

Description

[Technical Field]

[0001] The present disclosure relates to a magnetic sensor and a method for manufacturing a magnetic sensor, and more particularly to a magnetic sensor including a magnetic film and a protective film, and a method for manufacturing a magnetic sensor. [Background Art]

[0002] Patent Document 1 describes a magnetic sensor including a substrate, a magnetic film formed on the substrate, and a protective film covering the magnetic film formed on the substrate. The protective film includes an organic protective film and an inorganic protective film. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2004-186271 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] In the magnetic sensor of Patent Document 1, for example, warpage occurs in the substrate due to a difference in coefficient of thermal expansion between the substrate and the organic protective film, which may reduce detection accuracy (detection sensitivity).

[0005] An object of the present disclosure is to provide a magnetic sensor capable of improving detection accuracy and a method for manufacturing the magnetic sensor. [Means for Solving the Problem]

[0006] A magnetic sensor according to one aspect of the present disclosure comprises a substrate, a magnetic film, an inorganic protective film, and an organic protective portion. The magnetic film is disposed on the main surface of the substrate. The inorganic protective film is disposed to cover the magnetic film and has contact holes formed therein for passing through extraction wiring electrically connected to the magnetic film. The organic protective portion is disposed to cover a contact portion, which is a part of the surface of the inorganic protective film including the area corresponding to the contact holes. The ratio of the contact portion on which the organic protective portion is disposed to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range.

[0007] A method for manufacturing a magnetic sensor according to one aspect of the present disclosure includes a first arrangement step, a second arrangement step, a third arrangement step, a first forming step, and a second forming step. In the first arrangement step, a magnetic film is arranged on the main surface of a substrate. In the second arrangement step, an inorganic protective film is arranged to cover the magnetic film. In the first forming step, contact holes are formed in the inorganic protective film for passing through extraction wiring that is electrically connected to the magnetic film. In the third arrangement step, an organic protective film is arranged on the surface of the inorganic protective film. In the second forming step, an organic protective portion is formed to cover the contact portion by removing the remaining portion of the organic protective film by photolithography, excluding the portion corresponding to the contact portion, which is a part of the surface of the inorganic protective film that includes the area corresponding to the contact holes. The ratio of the contact portion on which the organic protective portion is arranged to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range.

[0008] A method for manufacturing a magnetic sensor according to one aspect of the present disclosure includes a first placement step, a second placement step, a first forming step, a mounting step, a second forming step, and a removal step. In the first placement step, a magnetic film is placed on the main surface of a substrate. In the second placement step, an inorganic protective film is placed so as to cover the magnetic film. In the first forming step, contact holes are formed in the inorganic protective film for passing through extraction wiring that is electrically connected to the magnetic film. In the mounting step, a hard mask having holes in a portion corresponding to a contact portion, which is a part of the surface of the inorganic protective film including the area corresponding to the contact holes, is attached to the surface of the inorganic protective film. In the forming step, an organic protective portion is formed by injection of an organic material using the hard mask, so as to cover the contact portion on the surface of the inorganic protective film. In the removal step, the hard mask is removed from the surface of the inorganic protective film on which the organic protective portion is formed. The ratio of the contact portion on which the organic protective portion is placed to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range. [Effects of the Invention]

[0009] The magnetic sensor and method for manufacturing the magnetic sensor described herein have the effect of improving detection accuracy. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a top view of a magnetic sensor according to an embodiment of the present disclosure. [Figure 2] Figure 2 is a cross-sectional view of the magnetic sensor according to the above embodiment. [Figure 3] Figure 3 is a top view of a magnetic sensor relating to a comparative example with the embodiment described above. [Figure 4] Figure 4 is a cross-sectional view of the magnetic sensor according to the comparative example above. [Figure 5]Figure 5 is a graph showing the amount of warping at each position along the main axis of the substrate for each of the magnetic sensors according to the embodiment described above, the magnetic sensor according to the comparative example described above, and the magnetic sensor according to another comparative example. [Figure 6] Figure 6 is a graph showing the relationship between the proportion of the contact area on the second surface (occupancy rate of the organic protective area) and the amount of warpage at the center of the substrate (maximum warpage) for each of the magnetic sensor according to the embodiment described above, the magnetic sensor according to the comparative example described above, and the magnetic sensor according to another comparative example described above. [Figure 7] Figure 7 is a graph showing the relationship between the occupancy rate and the characteristics of the magnetic film (strength of antiferromagnetic coupling Hk) for each of the magnetic sensors according to the above embodiment, the magnetic sensor according to the above comparative example, and the magnetic sensor according to another comparative example. [Figure 8] Figure 8 is a cross-sectional view illustrating the first manufacturing method of the magnetic sensor according to the above embodiment. [Figure 9] Figure 9 is a cross-sectional view illustrating a second manufacturing method for the magnetic sensor according to the above embodiment. [Figure 10] Figure 10 is a flowchart illustrating the first manufacturing method described above. [Figure 11] Figure 11 is a flowchart illustrating the second manufacturing method described above. [Modes for carrying out the invention]

[0011] This disclosure describes a magnetic sensor in which a magnetic film is placed on a substrate, and an inorganic protective film with contact holes is further placed on the magnetic film.

[0012] (1) Overview of the magnetic sensor according to the embodiment In the magnetic sensor according to the embodiment of this disclosure, an organic protective portion is arranged in a contact portion that includes an area corresponding to a contact hole on the inorganic protective film. The proportion of the contact portion on the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range.

[0013] The change in characteristics of the magnetic film is, for example, a change in magnetoresistance characteristics (MR characteristics) of the magnetic film caused by internal stress in the magnetic film generated in accordance with deformation of a substrate. The predetermined range for the change in characteristics of the magnetic film may be, for example, a range centered on the characteristics of the magnetic film when the ratio is "0", that is, when no organic protection portion is present on the inorganic protection film.

[0014] Note that various numerical values, various shapes, various materials, and the like given in the following description are merely examples and can be changed as appropriate.

[0015] (2) Details of the magnetic sensor according to the embodiment First, details of the magnetic sensor 1 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 and 2.

[0016] As shown in FIG. 2, the magnetic sensor 1 includes a substrate 10, a magnetic film 11, an inorganic protection film 12, and an organic protection portion 13.

[0017] (2-1) Substrate The substrate 10 in the present embodiment is formed in a plate shape from silicon (Si). As shown in FIG. 2, the substrate 10 has a main surface 10a.

[0018] (2-1-1) Main surface The main surface 10a is one of two surfaces facing each other in the thickness direction of the substrate 10 (in other words, their normal vectors are opposite to each other). In the present embodiment, the shape of the main surface 10a is rectangular.

[0019] In the following description, it is assumed that the magnetic sensor 1 is installed such that the main surface 10a of the substrate 10 is horizontal. Therefore, the thickness direction of the substrate 10 corresponds to the vertical direction (direction of a vertical line), and the direction of the normal vector of the main surface 10a is upward (vertically upward).

[0020] (2-2) Magnetic film The magnetic film 11 is a thin film that has magnetism. The magnetic film 11 is formed from a ferromagnetic material such as iron, nickel, cobalt, or chromium. In this embodiment, the magnetic film 11 has a multilayer structure in which magnetic layers made of ferromagnetic material are stacked. The multiple magnetic layers constituting the magnetic film 11 are antiferromagnetically coupled to each other, and the magnetic film 11 has a magnetoresistive effect (MR) in which its electrical resistance changes in response to an external magnetic field. The magnetic film 11 is placed on the substrate 10, that is, on the main surface 10a of the substrate 10.

[0021] (2-2-1) First surface The magnetic film 11 has a first surface 11a. The first surface 11a is the surface of the magnetic film 11 that is opposite to the substrate 10. In this embodiment, the first surface 11a is the upper surface of the upper and lower surfaces of the magnetic film 11.

[0022] (2-3) Inorganic protective film The inorganic protective film 12 is a thin film made of an inorganic material for protecting the magnetic film 11. The inorganic material is, for example, silicon dioxide (SiO2). The inorganic protective film 12 is positioned to cover the first surface 11a of the magnetic film 11.

[0023] (2-3-1) Second surface The inorganic protective film 12 has a second surface 12a. The second surface 12a is the surface of the inorganic protective film 12 that is opposite to the magnetic film 11. In this embodiment, the inorganic protective film 12 is placed on the magnetic film 11, that is, on the first surface 11a of the magnetic film 11.

[0024] (2-3-1a) Contact section The second surface 12a includes a contact portion 12p, as shown in Figures 1 and 2. The contact portion 12p is a part of the second surface 12a that includes the area corresponding to the contact hole 12c (described later) formed in the inorganic protective film 12.

[0025] In this embodiment, the contact portion 12p has a circular shape, as shown in Figure 1. The size (here, diameter) of the contact portion 12p is larger than the size (here, diameter) of the contact hole.

[0026] (2-3-1b) Contact Hole The inorganic protective film 12 has contact holes 12c formed therein for the extraction wiring 14 (described later) to pass through. The extraction wiring 14 is electrically connected to the magnetic film 11, and an electrical signal corresponding to the magnetoresistance effect of the magnetic film 11 is extracted to the outside of the magnetic sensor 1 via the extraction wiring 14.

[0027] (2-4) Organic protection part The organic protective part 13 is a component made of an organic material for protecting the contact hole 12c. In this embodiment, the organic protective part 13 has a screw shape (a shape combining a cylindrical shape and a frustoconical shape), as shown in Figures 1 and 2. The size of the organic protective part 13 (for example, the diameter of the cylindrical part) is slightly larger than the size of the contact hole 12c (for example, the diameter).

[0028] The organic protective portion 13 is positioned to cover the contact portion 12p of the second surface 12a. In this embodiment, the size of the organic protective portion 13 is the same as the size of the contact portion 12p. Therefore, only the contact portion 12p of the second surface 12a is covered by the organic protective portion 13 without excess or deficiency.

[0029] (2-4-1) Advantages of organic protective parts The organic protective portion 13 is positioned to cover the contact portion 12p within the second surface 12a of the inorganic protective film 12, thereby sealing the contact hole 12c formed in the inorganic protective film 12. As a result, it becomes more difficult for foreign matter (e.g., moisture, dust, etc.) to enter the contact hole 12c from outside the magnetic sensor 1.

[0030] In particular, the organic protective portion 13 covers the contact portion 12p completely and evenly, thereby suppressing changes in the properties of the magnetic film 11 due to deformation of the substrate 10. Specifically, of the second surface 12a of the inorganic protective film 12, only the contact portion 12p is covered by the organic protective portion 13, and the parts other than the contact portion 12p are not covered by the organic protective portion 13. This suppresses deformation of the substrate 10 due to stress generated between the substrate 10, which is bonded to the organic protective portion 13 via the inorganic protective film 12 and the magnetic film 11, and the organic protective portion 13. As a result, changes in the properties of the magnetic film 11 due to deformation of the substrate 10 are suppressed.

[0031] In this way, it becomes more difficult for foreign matter to enter the contact hole 12c from the outside, and the variation in the characteristics of the magnetic film 11 due to deformation of the substrate 10 is suppressed, thereby improving the detection accuracy of the magnetic sensor 1.

[0032] (2-5) Percentage of the contact area on the second surface The effect of suppressing the variation in the properties of the magnetic film 11 due to the deformation of the substrate 10 as described above depends on the proportion of the contact portion 12p on the second surface 12a of the inorganic protective film 12.

[0033] The ratio of the contact portion 12p on the second surface 12a where the organic protective portion 13 is located is such that the change in properties due to internal stress in the magnetic film 11, which occurs in response to the deformation of the substrate 10, remains within a predetermined range.

[0034] In this way, by setting the ratio of the contact portion 12p to the second surface 12a to such a ratio that the change in properties due to internal stress in the magnetic film 11 remains within a predetermined range, it is possible to prevent foreign matter from entering through the contact hole 12c while suppressing fluctuations in the properties of the magnetic film 11, and consequently improving the detection accuracy of the magnetic sensor 1.

[0035] (2-5-1) Occupancy of organic protective layer in inorganic protective layer When the organic protective portion 13 covers the contact portion 12p without excess or deficiency, the ratio of the contact portion 12p to the second surface 12a is the occupancy rate of the organic protective portion 13 on the inorganic protective film 12.

[0036] In this embodiment, the occupancy rate of the organic protective portion 13 on the inorganic protective film 12 (hereinafter sometimes simply referred to as "occupancy rate") is, for example, 5%.

[0037] (2-5-2) Details of substrate deformation: Warping of the substrate due to stress generated between the substrate and the organic protective layer. The deformation of the substrate 10 includes warping of the substrate 10 due to stress generated between it and the organic protective part 13.

[0038] (2-5-2a) Examples of substrate warping: "downward convex" warping and "upward convex" warping The warping of the substrate 10 due to the stress generated between it and the organic protective part 13 is, for example, a "downward convex" warp as shown in Figure 5. However, depending on the positional relationship between the substrate 10 and the organic protective part 13, the warping of the substrate 10 due to the stress generated between it and the organic protective part 13 may be an "upward convex" warp.

[0039] (2-5-2b) Internal stresses generated in the magnetic film due to substrate deformation: tensile stress and compressive stress As shown in Figure 5, when the substrate 10 bends downwards, tensile stress is generated inside the magnetic film 11. Also, when the substrate 10 bends upwards, compressive stress is generated inside the magnetic film 11.

[0040] (2-5-2c) Specific examples of substrate deformation Of the three types of dot sequences in Figure 5, the topmost circular dot sequence indicates the deformation of the substrate 10 that occurs in this embodiment. In other words, when the occupancy rate of the organic protective portion 13 on the inorganic protective film 12 is 5%, the stress generated between the organic protective portion 13 and the substrate 10 causes a slight downward convex warp, as shown by the circular dot sequence in Figure 5.

[0041] In the graph in Figure 5, the horizontal axis represents the coordinates (mm) in the direction of the main axis Ax1 or Ax2 (see Figure 1) of the substrate 10 (hereinafter referred to as the "main axis direction"), and the vertical axis represents the amount of warping of the substrate 10, i.e., the displacement in the thickness direction (μm) at each coordinate in the main axis direction.

[0042] In this specific example, the magnetic sensor 1 is a rectangular element with dimensions of approximately 3 mm in length and 3 mm in width when viewed from above. Multiple such magnetic sensors 1 are mounted so as to cover the main surface of a circular wafer with a diameter of approximately 100 mm when viewed from above. Mounting to cover the main surface basically means that the sensors are packed tightly together without any gaps, but partial gaps around the edges of the main surface are acceptable. The stress applied to the substrate 10 by each of the multiple magnetic sensors 1 mounted on the wafer is transmitted to the wafer, and the entire wafer deforms due to the stress from each of the multiple magnetic sensors 1. The amount of warpage shown in the graph of Figure 5 is the amount of warpage of the entire wafer. The same stress that occurs in the deformed wafer as shown in Figure 5 is applied to the multiple magnetic sensors 1 on the wafer, affecting the variation in MR characteristics.

[0043] (2-5-2d) Comparative example regarding substrate deformation In Figure 5, the bottom row of square dots indicates the deformation of the substrate 10 in the magnetic sensor 1A according to the comparative example shown in Figures 3 and 4. In the magnetic sensor 1A according to this comparative example, the occupancy rate of the organic protective film 13A on the magnetic film 11 is, for example, 90%. When the occupancy rate is 90%, a significant "downward convex" warp occurs in the substrate 10, as shown by the row of square dots in Figure 5.

[0044] Furthermore, in Figure 5, the series of dots in the middle triangle indicates the warping of the substrate 10 that occurs in a magnetic sensor (not shown) relating to another comparative example when the occupancy rate is 60%. When the occupancy rate is 60%, the substrate exhibits a moderate degree of "downward convex" warping, as shown by the series of dots in the triangle in Figure 5.

[0045] (2-5-2e) Relationship between occupancy rate and maximum warp Figure 6 shows the relationship between the occupancy rate and the maximum warpage for the embodiment (5% occupancy rate: circular dots in Figure 5), the comparative example (90% occupancy rate: rectangular dots in Figure 5), and another comparative example (60% occupancy rate: triangular dots in Figure 5). In the graph in Figure 6, the horizontal axis represents the occupancy rate (%) and the vertical axis represents the maximum warpage (μm).

[0046] The maximum warp is the largest warp among multiple warps corresponding to each of several positions (hereinafter sometimes referred to as "each position") along the principal axis direction of the substrate (for example, substrate 10 shown in Figures 2 and 4). The maximum warp is basically the warp at the center of the substrate.

[0047] In Figure 6, the circular dots indicate the relationship between occupancy rate and maximum warpage in the embodiment (occupancy rate of 5%, maximum warpage of -1 μm). The square dots indicate the relationship between occupancy rate and maximum warpage in the comparative example (occupancy rate of 90%, maximum warpage of -26 μm), and the triangular dots indicate the relationship between occupancy rate and maximum warpage in another comparative example (occupancy rate of 60%, maximum warpage of -15 μm).

[0048] From the arrangement of the three points in the graph in Figure 6, it can be seen that the smaller the occupancy rate, the smaller the maximum warp (in other words, the larger the occupancy rate, the larger the maximum warp).

[0049] (2-6) Specific examples of magnetic films The magnetic film 11 is, for example, a magnetic film (GMR film) that exhibits the giant magnetoresistive effect (GMR). The GMR film is formed from, for example, nickel-iron-cobalt alloy (NiFeCo) or nickel-iron-chromium alloy (NiFeCr).

[0050] By using a GMR film as the magnetic film 11, the detection accuracy of the magnetic sensor 1 can be improved.

[0051] (2-7) Details of the properties of magnetic films The properties of the magnetic film 11 include, for example, the magnetoresistance properties (MR properties). In this embodiment, the MR properties are the strength (Hk) of the antiferromagnetic coupling between the multiple magnetic layers constituting the magnetic film 11. In the following, this strength of antiferromagnetic coupling between magnetic layers may simply be referred to as "Hk".

[0052] The relationship between occupancy rate and Hk is shown in Figure 7. In the graph in Figure 7, the horizontal axis represents occupancy rate (in %), and the vertical axis represents Hk (in mT).

[0053] In the graph of Figure 7, point P1 shows the relationship between the occupancy rate and Hk in the magnetic sensor 1 according to the embodiment (occupancy rate is 5%, and Hk is 335mT). On the other hand, point P3 shows the relationship between the occupancy rate and Hk in the magnetic sensor 1A according to the comparative example (occupancy rate is 90%, and Hk is 315mT). Point P2 shows the relationship between the occupancy rate and Hk in another comparative example magnetic sensor (not shown) (occupancy rate is 60%, and Hk is 322mT). Point P0 shows Hk (336mT) when the occupancy rate is 0%.

[0054] A comparison of the graphs in Figure 6 and Figure 7 shows that the maximum curvature and Hk exhibit similar changes (positive correlation) with increases and decreases in occupancy.

[0055] Therefore, by using a change in Hk as the characteristic variation of the magnetic film 11, it is possible to suppress the deformation of the substrate 10 due to stress generated between it and the organic protective part 13, and consequently, the fluctuation in the strength of the antiferromagnetic coupling (Hk) due to the generation of internal stress in the magnetic film 11 in response to the deformation of the substrate 10. As a result, the detection accuracy of the magnetic sensor 1 can be improved.

[0056] (2-8) Details of the predetermined range regarding changes in characteristics The predetermined range for the change in characteristics is, for example, a range defined by at least one of an upper limit and a lower limit with respect to Hk. In this embodiment, the predetermined range is defined by both an upper limit and a lower limit with respect to Hk. The predetermined range may be, for example, a range centered on or approximately centered on the Hk of the magnetic film 11 when the occupancy rate is 0%.

[0057] (2-8-1) Specific examples of the specified range The predetermined range is, specifically, the range shown by the two dashed lines in the graph of Figure 7, that is, the range in which Hk is 330 mT or more and 340 mT or less. More specifically, in this particular example, the Hk of the magnetic film 11 when the occupancy rate is 0% is 336 mT, corresponding to point P0, as mentioned above, and the predetermined range is a range that is roughly centered around this value of 336 mT.

[0058] Note that the predetermined range shown in Figure 7 is illustrative and is determined by considering, for example, the type of various materials such as the magnetic material of the magnetic film 11 and the organic material of the organic protective part 13, the thickness of various films such as the magnetic film 11, the target detection accuracy of the magnetic sensor 1, etc., in addition to or instead of the Hk of the magnetic film 11 when the occupancy rate is 0%.

[0059] In the magnetic sensor 1 according to this embodiment, as shown by point P1 in the graph of Figure 7, the occupancy rate is 5%, and the strength of Hk is 335 mT, which is within a predetermined range. Therefore, the characteristics of the magnetic film 11 can be stabilized, and as a result, the detection accuracy of the magnetic sensor 1A can be improved.

[0060] (2-9) Electrical configuration: Take-out wiring and electrode pads As shown in Figures 1 and 2, the magnetic sensor 1 further comprises the aforementioned extraction wiring 14 and electrode pads 15.

[0061] The extraction wiring 14 is located on the second surface 12a of the inorganic protective film 12, as shown in Figure 1. The extraction wiring 14 includes an extraction electrode 14e, as shown in Figure 2. The extraction electrode 14e is connected to the electrode pad 15 by passing through the contact hole 12c.

[0062] The electrode pad 15 is positioned on the first surface 11a of the magnetic film 11. The electrode pad 15 may be, for example, a pattern formed on the first surface of the magnetic film 11, as shown in Figure 1 (in this case, a zigzag pattern). Furthermore, the sensor body of the magnetic sensor 1 may be formed by the electrode pad 15 as shown in Figure 1.

[0063] In the magnetic sensor 1 of this embodiment, as shown in Figure 2, the tip of the extraction electrode 14e, which is part of the extraction wiring 14, penetrates the contact hole 12c and comes into contact with the electrode pad 15 on the magnetic film 11, thereby electrically connecting the extraction wiring 14 to the magnetic film 11.

[0064] With this configuration, an electrical signal corresponding to a change in the external magnetic field can be extracted from the magnetic film 11 of the magnetic sensor 1 via the electrode pad 15 and the extraction wiring 14.

[0065] (2-10) Arrangement of organic protective elements on inorganic protective film The organic protection section 13 is arranged symmetrically with respect to the main axis AX1 or Ax2 (see Figure 1) of the substrate 10. The main axis AX1 or Ax2 is a straight line that passes through the center of the main surface 10a of the substrate 10 and is parallel to the main surface 10a. For example, if the main surface 10a of the substrate 10 is rectangular, the main axis is a straight line that passes through the center of the main surface 10a and is parallel to one of the two mutually perpendicular sides of the main surface 10a (in the example in Figure 1, the vertical center line or the horizontal center line).

[0066] According to this embodiment, the stress generated between the substrate 10 and the organic protective part 13, such as tensile stress or compressive stress, occurs symmetrically with respect to the principal axis of the substrate 10. As a result, the change in the properties of the magnetic film becomes isotropic, and thus the detection accuracy when detecting rotation can be improved.

[0067] (2-11) Advantages of the magnetic sensor according to the embodiment In the magnetic sensor 1 according to this embodiment, the contact portion 12p of the inorganic protective film 12 covering the magnetic film 11 placed on the substrate 10, which corresponds to the area including the contact hole 12c, is covered with an organic protective portion 13, thereby preventing foreign matter from entering the magnetic film 11 from the contact hole 12c. Furthermore, by setting the ratio of the contact portion 12p to the second surface 12a of the inorganic protective film 12 to a ratio in which the variation in the characteristics of the magnetic film 11 in response to the deformation of the substrate 10 is within a predetermined range, the characteristics of the magnetic film 11 can also be stabilized. As a result, the detection accuracy of the magnetic sensor 1 can be improved.

[0068] (3) Details of the comparative example Next, the details of the magnetic sensor 1A related to the comparative example described above will be explained using Figures 3 and 4. Note that in the following, explanations of matters common to the embodiment will be omitted or simplified.

[0069] As shown in Figure 1, the magnetic sensor 1 of the embodiment is equipped with an organic protective portion 13 (occupancy rate 5%) that covers the contact portion 12p which occupies 5% of the second surface 2a. In contrast, the magnetic sensor 1A of this comparative example is equipped with an organic protective film 13A (occupancy rate 90%) that covers 90% of the second surface 2a, as shown in Figure 3, instead of the organic protective portion 13. As shown in Figure 3, the surface of the organic protective film 13A is rectangular and covers 90% of the inorganic protective film 12, excluding the peripheral edge. Therefore, all contact holes 12c of the inorganic protective film 12 are covered with the organic protective film 13A, thus preventing a decrease in the detection accuracy of the magnetic sensor 1A due to the intrusion of foreign matter into the contact holes 12c.

[0070] As shown in Figure 4, the organic protective film 13A has holes 13h that penetrate in the thickness direction of the organic protective film 13A, and the external wiring is electrically connected to the output wiring 14 located on the second surface 12a by passing through the holes 13h of the organic protective film 13A.

[0071] The amount of warping at each position of the substrate 10 of the magnetic sensor 1A in the comparative example is larger than the amount of warping at each position of the substrate 10 of the magnetic sensor 1 according to the embodiment (as shown by the sequence of square dots in Figure 5) (i.e., the "downward convex" warping is more pronounced).

[0072] Therefore, the maximum warp at the center of the substrate 10 of the magnetic sensor 1A according to the comparative example is larger than the maximum warp at the center of the substrate 10 of the magnetic sensor 1 according to the embodiment (circular dot: occupancy rate 5%, maximum warp at a maximum of -1μm), as shown by the square dot in Figure 6 (occupancy rate 90%, maximum warp at a maximum of -27μm).

[0073] In the comparative example, the Hk value of magnetic sensor 1A is 315 mT, as shown by point P3 in Figure 7, with an occupancy rate of 90%. This value falls outside the specified range. Therefore, in the comparative example, the characteristics of the magnetic film 10A cannot be stabilized, making it difficult to achieve the accuracy improvement required to reach the target detection accuracy of magnetic sensor 1A.

[0074] (4) Details of other comparative examples The magnetic sensor in the other comparative example mentioned above differs from the magnetic sensor 1A (occupancy rate 90%) in that its occupancy rate is 60%.

[0075] While the organic protective film 13A of the comparative example magnetic sensor 1A is rectangular in shape, the organic protective film of the other comparative example magnetic sensor has a donut shape, for example, with a missing portion corresponding to the central part where there are no contact holes in the inorganic protective film. The donut-shaped organic protective film covers all the contact holes of the inorganic protective film 12, even though the occupancy rate is 60%. Therefore, in the other comparative example magnetic sensor as well, the decrease in magnetic sensor detection accuracy due to the intrusion of foreign matter into the contact holes can be avoided.

[0076] The amount of warping at each position of the substrate of the magnetic sensor according to the other comparative example is larger than the amount of warping at each position of the substrate 10 of the magnetic sensor 1 according to the embodiment (sequence of circular dots), as shown by the sequence of triangular dots in Figure 5, but smaller than the amount of warping at each position of the substrate 10 of the magnetic sensor 1A according to the comparative example (sequence of circular dots) (i.e., the "downward convex" warping is moderate).

[0077] Therefore, the maximum amount of warpage at the center of the substrate of the magnetic sensor according to the other comparative example is larger than the maximum amount of warpage at the center of the substrate 10 of the magnetic sensor 1 according to the embodiment (circular dot), as shown by the triangular dot in Figure 6, but smaller than the maximum amount of warpage at the center of the substrate 10 of the magnetic sensor 1A according to the comparative example (square dot).

[0078] In the magnetic sensor relating to the other comparative example, as shown by point P2 in Figure 7, the occupancy rate is 60% and the strength of Hk is 322 mT, which is not within the specified range. Therefore, in the magnetic sensor relating to the other comparative example, although some improvement in detection accuracy can be expected due to the stabilization of the characteristics of the magnetic film 11, it is insufficient to achieve the accuracy improvement required to reach the target detection accuracy.

[0079] (5) Specific examples of the proportion (occupancy rate) such that the change in the properties of the magnetic film is within a predetermined range. From the various specific examples, comparative examples, and other comparative examples described in the embodiments, the percentage (occupancy rate) such that the change in the properties of the magnetic film 11 falls within a predetermined range is, for example, the following value.

[0080] In other words, in the graph of Figure 7, the occupancy rate at the intersection of the dashed line corresponding to the lower limit (i.e., the straight line "Hk=4") and the straight line along the four points P0 to P3 (the straight line shown by the dashed line) of the two dashed lines corresponding to the upper and lower limits of the predetermined range (for example, approximately 30%) is the maximum occupancy rate such that the change in Hk of the magnetic film 11 is within the predetermined range. Therefore, in this specific example, the occupancy rate should be 30% or less.

[0081] (6) Method for manufacturing a magnetic sensor: First manufacturing method A method for manufacturing the magnetic sensor 1 according to this embodiment (first manufacturing method) will be described with reference to Figures 8 and 10. The first manufacturing method includes the formation of the organic protective part 13 by photolithography.

[0082] The series of steps S1 to S7 shown in the flowchart of Figure 10 are basically performed automatically by the manufacturing equipment. However, some of the steps S1 to S7 may be performed semi-automatically or manually in response to human intervention.

[0083] When the manufacturing of the magnetic sensor 1 begins, a magnetic film 11 is first placed on the main surface 10a of the substrate 10 by coating it with a magnetic material. Then, an electrode pad 15 is placed on the first surface 11a of the magnetic film 11 (step S1).

[0084] Next, by applying a magnetic material onto the magnetic film 11, the inorganic protective film 12 is positioned to cover the magnetic film 11 (step S2). Then, by performing photolithography or etching with a chemical agent on the inorganic protective film 12, contact holes 12c are formed in the inorganic protective film 12 (step S3).

[0085] Next, the extraction wiring 14 is placed on the second surface 12a of the inorganic protective film 12 by attaching the extraction wiring 14 to the inorganic protective film 12 (step S4).

[0086] Next, by applying an organic material onto the inorganic protective film 12, the organic protective film 13A is positioned on the second surface 12a of the inorganic protective film 12 (step S5). When step S5 is completed, the magnetic sensor 1 will be in the state shown in the upper part of Figure 8.

[0087] Next, the remaining portion of the organic protective film 13A, excluding the portion corresponding to the contact portion 12p of the second surface 12a, is removed by photolithography using the photomask PM1 to form an organic protective portion 13 that covers the contact portion 12p (step S6).

[0088] Furthermore, when the photomask PM1 is placed on the organic protective film 13A, a certain area centered on the contact hole 12c (corresponding to the contact portion 12p) is opaque, while the area outside this certain area (the area other than the contact portion 12p) is transparent, i.e., light-transmitting. Therefore, as shown in the middle of Figure 8, light L1 directed towards the certain area centered on the contact hole 12c is blocked by the opaque portion of the photomask PM1, and only light L2 directed towards the area outside the certain area passes through the transparent portion of the photomask PM1 and irradiates the organic protective film 13A. As a result, the portion of the organic protective film 13A that has been irradiated with light L2 is removed, resulting in the formation of the organic protective portion 13 that covers the contact portion 12p, as shown in the lower part of Figure 8.

[0089] Next, the organic protection part 13 is subjected to heat treatment (step S7). This completes the manufacturing of the magnetic sensor 1.

[0090] According to the manufacturing method (first manufacturing method) of the embodiment, a magnetic sensor 1 with high detection accuracy can be efficiently manufactured by forming the organic protective part 13 covering the contact part 12p by photolithography. For example, the efficiency of manufacturing can be improved by performing both the formation of the contact hole 12c and the formation of the organic protective part 13 by photolithography.

[0091] (7) Variant The following describes various modifications related to the embodiments. Note that in the following, explanations of matters common to the embodiments will be omitted or simplified, and the differences will be explained in detail.

[0092] (7-1) Modified method of manufacturing a magnetic sensor: Second manufacturing method A modified manufacturing method (second manufacturing method) of the magnetic sensor 1 according to the embodiment will be described with reference to Figures 9 and 11. The second manufacturing method includes lift-off using a hard mask HM1.

[0093] The series of steps S1-S4, S5a, S6a, S6b, and S7 shown in the flowchart of Figure 11 are basically performed automatically by the manufacturing equipment. However, some of the series of steps S1-S4, S5a, S6a, S6b, and S7 may be performed semi-automatically or manually in response to human intervention.

[0094] When the manufacturing of the magnetic sensor 1 begins, a magnetic film 11 is first placed on the main surface 10a of the substrate 10 by coating it with a magnetic material. Then, an electrode pad 15 is placed on the first surface 11a of the magnetic film 11 (step S1).

[0095] Next, by applying a magnetic material onto the magnetic film 11, the inorganic protective film 12 is positioned to cover the magnetic film 11 (step S2). Then, by performing photolithography or etching with a chemical agent on the inorganic protective film 12, contact holes 12c are formed in the inorganic protective film 12 (step S3).

[0096] Next, the extraction wiring 14 is placed on the second surface 12a of the inorganic protective film 12 by attaching the extraction wiring 14 to the inorganic protective film 12 (step S4).

[0097] Next, the hard mask HM1 is attached to the second surface 12a of the inorganic protective film 12 (step S5a). As shown in the upper part of Figure 9, when the hard mask HM1 is attached to the inorganic protective film 12, it has holes HM1h in the portion of the second surface 12a of the inorganic protective film 12 that corresponds to the contact portion 12p.

[0098] Next, an organic material is applied to the hard mask HM1. Then, as shown in the middle of Figure 9, the organic material is ejected from the holes HM1h of the hard mask HM1 by lift-off using the hard mask HM1, thereby forming an organic protective portion 13 that is positioned to cover the contact portion 12p of the second surface 12a (step S6a).

[0099] Next, the hard mask HM1 is removed from the second surface 12a of the inorganic protective film 12, along with any remaining organic material on the hard mask HM1 (step S6b). At the completion of step S6b, the magnetic sensor 1 will be in the state shown in the lower part of Figure 9.

[0100] Next, heat treatment is performed on the organic protection part 13 (step S7). This completes the manufacturing of the magnetic sensor 1. The organic material remaining on the removed hard mask HM1 will be reused in the next manufacturing cycle.

[0101] According to the modified manufacturing method (second manufacturing method), by forming the organic protective portion 13 covering the contact portion 12p by lift-off, it is possible to manufacture a magnetic sensor 1 with high detection accuracy while suppressing the amount of organic material used, for example, compared to the case where it is formed by photolithography (first manufacturing method).

[0102] (7-2) Modified form of magnetic film The magnetic film 11 may be, for example, a magnetic film having an anisotropic magnetoresistive effect (AMR) or a tunnel magnetoresistance effect (TMR). In other words, the type of magnetoresistance effect that the magnetic film 11 has is not relevant.

[0103] (7-3) Modified examples relating to the properties of magnetic films The properties of the magnetic film 11 used to define the ratio of the contact portion 12p to the second surface 12a (the occupancy rate of the organic protective portion 13 on the inorganic protective film 12) may be properties other than the strength of the antiferromagnetic coupling (Hk: see Figure 7), such as the strength of a magnetic field, including an anisotropic magnetic field.

[0104] (7-4) Modifications relating to materials for substrates, inorganic magnetic films, and organic magnetic parts The substrate 10 may be formed from a material other than silicon, such as silicon carbide (SiC) or glass.

[0105] The inorganic protective film 12 may be formed from an inorganic material other than silicon dioxide, such as boron oxide (B2O3).

[0106] The organic protective portion 13 may be formed of an organic material other than polyimide, such as polypropylene.

[0107] (7-5) Variations concerning organic protection The organic protective part 13 may have a shape other than the screw shape (Figures 1 and 2). For example, either the cylindrical shape or the frustoconical shape m that constitutes the screw shape may be omitted.

[0108] (7-6) Variations of the size of the contact area The size of the contact portion 12p may be the same as the size of the contact hole 12c.

[0109] (7-7) Variations related to photolithography When forming the organic protective portion 13 on the organic protective film 13A by photolithography, instead of using a photomask, the organic protective portion 13 may be formed by irradiating the organic protective film 13A with a laser in the area corresponding to the transparent part of the photomask, and not irradiating the area corresponding to the opaque part of the photomask.

[0110] (8) Summary The magnetic sensor (1) according to the first embodiment comprises a substrate (10), a magnetic film (11), an inorganic protective film (12), and an organic protective part (13). The magnetic film (11) is disposed on the main surface (10a) of the substrate (10). The inorganic protective film (12) is disposed to cover the magnetic film (11) disposed on the main surface (10a), and has contact holes (12c) formed therein for passing through extraction wiring (14) that is electrically connected to the magnetic film (11). The organic protective part (13) is disposed to cover a contact portion (12p) of the surface (12a) of the inorganic protective film (12), which includes the area corresponding to the contact holes (12c). The ratio of the contact portion (12p) on which the organic protective part (13) is disposed to the surface (12a) of the inorganic protective film (12) is such that the change in the properties of the magnetic film (11) is within a predetermined range.

[0111] According to this embodiment, by covering the contact portion (12p) of the inorganic protective film (12) covering the magnetic film (11) placed on the substrate (10), which corresponds to the area including the contact hole (12c), with the organic protective portion (13), it is possible to prevent foreign matter from entering the magnetic film (11) from the contact hole (12c). Furthermore, by setting the ratio of the contact portion (12p) to the inorganic protective film (12) to a ratio in which the variation in the characteristics of the magnetic film (11) is within a predetermined range, it is possible to stabilize the characteristics of the magnetic film, and as a result, the detection accuracy of the magnetic sensor (1) can be improved.

[0112] A magnetic sensor (1) according to a second embodiment further comprises, in the first embodiment, an electrode pad (15) and an extraction wiring (14). The electrode pad (15) is located on a magnetic film (11). The extraction wiring (14) is located on the surface (12a) of an inorganic protective film (12). The extraction wiring (14) includes an extraction electrode (14e) that penetrates a contact hole (12c) and is connected to the electrode pad (15).

[0113] According to this embodiment, it is possible to extract an electrical signal in response to a change in the magnetic field.

[0114] In the magnetic sensor (1) according to the third embodiment, in the first or second embodiment, the change is a change in the magnetoresistance characteristics of the magnetic film (11) due to the internal stress of the magnetic film (11) that occurs in response to the deformation of the substrate (10).

[0115] According to this embodiment, the proportion of the contact portion (12p) to the second surface (12a) can be determined based on the relationship between the deformation of the substrate (10), the internal stress of the organic protective portion (13), and the magnetoresistance.

[0116] In the magnetic sensor (1) according to the fourth embodiment, in the third embodiment, the deformation of the substrate (10) includes deformation due to stress generated between the substrate (10) and the organic protective part (13).

[0117] According to this embodiment, by keeping the proportion of the contact portion (12p) in the inorganic protective film (12) within a predetermined range, stress generated between the substrate (10) and the organic protective portion (13) can be suppressed, thereby suppressing deformation of the substrate (10) due to stress and changes in the properties of the magnetic film (11) due to deformation of the substrate (10).

[0118] In the magnetic sensor (1) according to the fifth embodiment, in any of the first to fourth embodiments, the magnetic film (11) has a multilayer structure in which magnetic layers made of ferromagnetic material are stacked. The characteristic is the strength (Hk) of the antiferromagnetic coupling between the magnetic layers in the magnetic film (11).

[0119] According to this embodiment, deformation of the substrate (10) due to stress generated between the substrate (10) and the organic protective part (13), and consequently, fluctuations in the strength (Hk) of the antiferromagnetic coupling due to internal stress generated in the magnetic film (11) in response to the deformation of the substrate (10), can be suppressed.

[0120] In the magnetic sensor (1) according to the sixth embodiment, in any of the first to fifth embodiments, the magnetic film (11) has a multilayer structure in which magnetic layers made of ferromagnetic material are stacked. The ratio is such that the change in the strength (Hk) of the antiferromagnetic bonding between magnetic layers in the magnetic film (11) due to tensile stress or compressive stress, which is the internal stress of the magnetic film (11) that occurs in response to the deformation of the substrate (10), is within a predetermined range. The deformation of the substrate (10) is caused by the difference in thermal expansion coefficients between the organic protective part (13) and the substrate (10).

[0121] According to this embodiment, when arranging the organic protective portion (13) in the contact portion (12p) which includes the area corresponding to the contact hole (12c) of the inorganic protective film (12), the ratio of the contact portion (12p) to the inorganic protective film (12) is set to a ratio such that the fluctuation of the antiferromagnetic coupling strength (Hk) is within a predetermined range. This suppresses the intrusion of foreign matter from the contact hole (12c) while stabilizing the antiferromagnetic coupling strength (Hk) in the magnetic film (11), and consequently improving the detection accuracy of the magnetic sensor (1).

[0122] In the magnetic sensor (1) according to the seventh embodiment, in any of the first to sixth embodiments, the magnetic film (11) is a magnetic film having a giant magnetoresistance effect.

[0123] According to this embodiment, the detection accuracy of the magnetic sensor (1) can be improved by using a magnetic film having GMR.

[0124] In the magnetic sensor (1) according to the eighth embodiment, in any of the first to seventh embodiments, the organic protective portion (13) is arranged symmetrically with respect to a straight line that passes through the center of the main surface (10a) and is parallel to the main surface (10a).

[0125] According to this embodiment, the internal stress (e.g., tensile stress or compressive stress) generated in the magnetic film (11) occurs symmetrically with respect to the principal axis (AX1, Ax2) of the substrate (10), resulting in isotropic changes in the properties of the magnetic film (11). As a result, the detection accuracy when detecting rotation with the magnetic sensor (1) can be improved.

[0126] A method for manufacturing a magnetic sensor (1) according to the ninth embodiment includes a first arrangement step (S1), a second arrangement step (S2), a first forming step (S3), a third arrangement step (S5), and a forming step (S6). In the first arrangement step (S1), a magnetic film (11) is arranged on the main surface (10a) of a substrate (10). In the second arrangement step (S2), an inorganic protective film (12) is arranged to cover the magnetic film (11) arranged on the main surface (10a). In the first forming step (S3), contact holes (12c) are formed in the inorganic protective film (12) for passing through extraction wiring (14) that is electrically connected to the magnetic film (11). In the third arrangement step (S5), an organic protective film (13A) is arranged on the surface (12a) of the inorganic protective film (12). In the formation step (S6), the remaining portion of the organic protective film (13A), excluding the contact portion (12p) which is a part of the inorganic protective film (12a) including the contact hole (12c), is removed by photolithography using a photomask (PM1), thereby forming an organic protective portion (13) that covers the contact portion (12p). The ratio of the contact portion (12p) on which the organic protective portion (13) is located to the surface (12a) of the inorganic protective film (12) is such that the change in the properties of the magnetic film (11) is within a predetermined range.

[0127] According to this embodiment, a magnetic sensor (1) with high detection accuracy can be efficiently manufactured by forming an organic protective part (13) covering the contact part (12p) by photolithography. For example, manufacturing efficiency can be improved by performing both the formation of the contact hole (12c) and the formation of the organic protective part (13) by photolithography.

[0128] A method for manufacturing a magnetic sensor (1) according to the tenth embodiment includes a first placement step (S1), a second placement step (S2), a first forming step (S3), a mounting step (S5a), a second forming step (S6a), and a removal step (S6b). In the first placement step (S1), a magnetic film (11) is placed on the main surface (10a) of a substrate (10). In the second placement step (S2), an inorganic protective film (12) is placed so as to cover the magnetic film (11) placed on the main surface (10a). In the first forming step (S3), a contact hole (12c) is formed in the inorganic protective film (12) for passing through an extraction wiring (14) that is electrically connected to the magnetic film (11). In the mounting step (S5a), a hard mask (HM1) having holes (HM1h) in a portion corresponding to the contact portion (12p), which is a part of the surface (12a) of the inorganic protective film (12) that includes the area corresponding to the contact hole (12c), is attached to the surface (12a) of the inorganic protective film (12). In the forming step (S6a), an organic protective portion (13) is formed by injection of organic material using the hard mask (HM1), and is positioned to cover the contact portion (12p) of the surface (12a) of the inorganic protective film (12). In the removal step (S6b), the hard mask (HM1) is removed from the surface (12a) of the inorganic protective film (12) on which the organic protective portion (13) has been formed. The ratio of the contact portion (12p) on which the organic protective portion (13) is located to the surface (12a) of the inorganic protective film (12) is such that the change in the properties of the magnetic film (11) is within a predetermined range.

[0129] According to this embodiment, by forming the organic protective portion (13) covering the contact portion (12p) by injection (lift-off) of an organic material, it is possible to manufacture a magnetic sensor (1) with high detection accuracy while reducing the amount of organic material used, for example, compared to forming it by photolithography. [Explanation of Symbols]

[0130] 1. Magnetic sensor 10 circuit boards 10a Main surface 11 Magnetic film 11a 1st surface 12 Inorganic protective film 12a 2nd surface (front) 12p Contact section 12c Contact Hole 13 Organic protection part 13A Organic protective film 14. Extraction wiring 14e Extraction electrode 15 electrode pads HM1 Hard Mask HM1h hole

Claims

1. circuit board and A magnetic film disposed on the main surface of the substrate, An inorganic protective film is provided, which is arranged to cover the magnetic film disposed on the main surface and has contact holes formed therein for passing through extraction wiring that is electrically connected to the magnetic film. The inorganic protective film comprises an organic protective portion disposed to cover a contact portion, which is a part of the surface of the inorganic protective film including the area corresponding to the contact hole, The proportion of the contact portion on which the organic protective portion is arranged to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range. Magnetic sensor.

2. An electrode pad arranged on the magnetic film, The inorganic protective film further comprises the extraction wiring arranged on the surface of the inorganic protective film, The extraction wiring includes an extraction electrode that passes through the contact hole and is connected to the electrode pad. The magnetic sensor according to claim 1.

3. The aforementioned change is a change in the magnetoresistance characteristics of the magnetic film due to the internal stress of the magnetic film that occurs in response to the deformation of the substrate. The magnetic sensor according to claim 1 or 2.

4. The deformation includes deformation due to stress occurring between the substrate and the organic protective part. The magnetic sensor according to claim 3.

5. The magnetic film has a multilayer structure in which magnetic layers formed of ferromagnetic material are stacked. The aforementioned characteristic is the strength of the antiferromagnetic coupling between magnetic layers in the magnetic film. The magnetic sensor according to claim 1 or 2.

6. The magnetic film has a multilayer structure in which magnetic layers formed of ferromagnetic material are stacked. The aforementioned ratio is such that the change in the strength of the antiferromagnetic coupling between magnetic layers in the magnetic film, due to tensile stress or compressive stress which is the internal stress of the magnetic film resulting from the deformation of the substrate caused by the difference in thermal expansion coefficients between the organic protective portion and the substrate, falls within a predetermined range. The magnetic sensor according to claim 1 or 2.

7. The magnetic film is a magnetic film having a giant magnetoresistance effect. The magnetic sensor according to claim 1 or 2.

8. The organic protective portion is arranged symmetrically with respect to a line passing through the center of the main surface and parallel to the main surface. The magnetic sensor according to claim 1 or 2.

9. A first placement step involves placing a magnetic film on the main surface of the substrate, A second arrangement step involves arranging the inorganic protective film so as to cover the magnetic film arranged on the main surface, A first forming step involves forming contact holes in the inorganic protective film for passing through extraction wiring that is electrically connected to the magnetic film, A third arrangement step involves placing an organic protective film on the surface of the inorganic protective film, The second forming step includes removing, by photolithography, the remaining portion of the organic protective film, excluding the portion corresponding to the contact portion which is a part of the inorganic protective film including the area of ​​the surface corresponding to the contact hole, thereby forming an organic protective portion arranged to cover the contact portion. The proportion of the contact portion on which the organic protective portion is arranged to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range. A method for manufacturing magnetic sensors.

10. A first placement step involves placing a magnetic film on the main surface of the substrate, A second arrangement step involves arranging the inorganic protective film so as to cover the magnetic film arranged on the main surface, A first forming step involves forming contact holes in the inorganic protective film for passing through extraction wiring that is electrically connected to the magnetic film, A mounting step of attaching a hard mask having holes in a portion corresponding to a contact portion, which is a part of the surface of the inorganic protective film that includes the area corresponding to the contact holes, to the surface of the inorganic protective film; A second forming step involves injecting an organic material using the hard mask to form an organic protective portion that is positioned to cover the contact portion on the surface of the inorganic protective film, The step includes removing the hard mask from the surface of the inorganic protective film on which the organic protective portion is formed, The proportion of the contact portion on which the organic protective portion is arranged to the surface of the inorganic protective film is such that the change in the properties of the magnetic film is within a predetermined range. A method for manufacturing magnetic sensors.

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