JP2009123818A - Method of manufacturing magnetic sensor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve high precision in shape of a conductive part in order to improve performance of a magnetic sensor device in the method of manufacturing magnetic sensor device. <P>SOLUTION: The method of manufacturing magnetic sensor device includes a step of forming a silicon oxide layer 7 as a sacrifice layer pattern having an opening 6 at the upper side of a barrier layer, a step of forming a metal film covering this silicon oxide layer, a step of removing a part at the bottom part of the opening 6 of this metal film by isotropic etching thereof to selectively leave a part covering the upper side of the sacrifice layer pattern and a part protruded in the circumference thereof, a step of forming a conductive layer 11 by deposition thereof from the upper side of these portions, and a conductive layer patterning step of removing at a time the metal film pattern and conductive layer 11 at the upper side thereof by removing the sacrifice layer pattern and leaving the conductive layer at the bottom part of the opening 6 as a conductive part 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a magnetic sensor device. In particular, the present invention relates to a method for manufacturing a magnetic sensor device having a current line therein and formed of a thin film.

  Conventionally, a barber pole structure is known as a magnetic sensor device. The “barber / pole structure” is a structure in which a plurality of strip-shaped conductive portions are arranged obliquely in parallel at regular intervals within a certain elongated rectangular region on a substrate. As a method for producing a magnetic sensor device having this structure, particularly a method for producing a conductive portion thereof, for example, there is one described in JP-T-2004-536453 (Patent Document 1). The method includes depositing an insulating layer on the device; etching a barber pole window in the insulating layer; depositing a conductive material on the insulating layer and in the barber pole window; Etching away the conductive material between the barber pole windows to form a barber pole structure.

  Further, as a conventional method for producing a thin film fine pattern, for example, there is one described in Japanese Patent Laid-Open No. 05-62948 (Patent Document 2). The method includes the steps of depositing a photoresist on an object, patterning (removing) a deposition portion on the photoresist, depositing a desired material on and in the photoresist, And a lift-off step of forming a fine deposition portion by dissolving the resist.

Further, for example, as described in Japanese Patent Application Laid-Open No. 2005-302881 (Patent Document 3), a sacrificial layer composed of a two-layer resist pattern (hereinafter referred to as “two-layer resist”) and a soluble layer is provided. There is a method of forming a fine thin film pattern without burrs by using it.
Special table 2004-536453 gazette JP 05-62948 A JP 2005-302881 A

  In the operation of a magnetic sensor device having a current line inside, the application of a uniform magnetic field from the current line to the element is important in ensuring the performance of the device. It is necessary to produce a flat current line that is not present. When a conductive portion having a barber-pole structure is manufactured by the method disclosed in Patent Document 1, each conductive portion is finished to have a steep step shape. Therefore, when another current line is stacked on the upper layer of the conductive part thus finished via an insulating layer, the other current line must be formed on a surface having a step and an unevenness. There is a problem that it is difficult to form a flat line.

  Therefore, as a countermeasure against this problem, a lift-off method that can form a smooth step can be considered. However, although the conventional lift-off process is effective from the viewpoint of reducing the level difference and unevenness, there is a problem that the frequency of occurrence of burrs at the boundary between the conductive part and the element increases.

  Furthermore, even when a two-layer resist is used, the occurrence probability of burrs is reduced as compared with the case of using a single-layer resist, but there is a problem that the generation of burrs cannot be completely avoided because the undercut amount is small. It was. Furthermore, when forming a thick conductive portion of several thousand liters, there is a problem that resist residues due to thermal degradation during film formation cannot be avoided.

  The present invention has been made to solve the above-described problems. In a method of manufacturing a thin film magnetic sensor device having a current line therein, steps and irregularities on the surface of a magnetoresistive effect element having a conductive portion are formed. An object of the reduction is to improve the flatness of current lines formed in the vicinity of the element apart from the magnetoresistive element. Furthermore, it aims at providing the manufacturing method of a magnetic sensor device which can obtain the magnetic sensor device which improved the performance by the highly accurate conductive part shape.

  In order to achieve the above object, a method of manufacturing a magnetic sensor device according to the present invention includes a step of forming a magnetoresistive effect element on a top surface of a substrate via a first insulating layer, and a barrier covering the upper side of the magnetoresistive effect element. Forming a layer, forming a sacrificial layer pattern having an opening above the barrier layer, forming a metal film so as to cover the sacrificial layer pattern, and isolating the metal film isotropic Etching to remove a portion of the metal film at the bottom of the opening, and selectively leaving a portion covering the upper side of the sacrificial layer pattern and a portion protruding around the sacrificial layer pattern, and the sacrificial layer pattern Forming a conductive layer so as to be deposited from above on the upper side of the metal film pattern on the upper side and on the bottom of the opening, and removing the sacrificial layer pattern, Removed collectively the conductive layer on the upper side of Shokumaku pattern and the metal film pattern, and a conductive layer patterning step to leave the conductive layer at the bottom of the opening.

  According to the present invention, it is possible to avoid resist residues due to thermal degradation during film formation caused by the conventional two-layer resist method as described in Patent Document 3, and to have an eaves shape with a large undercut amount. Since a thick structure can be formed, burrs at the time of thick film formation can be suppressed, and a smooth conductive portion (barber pole (BBP) electrode) having a sufficient thickness of several thousand mm can be manufactured. Since steps and irregularities on the surface of the element having the conductive portion are reduced, the shape of the conductive portion can be realized with high accuracy and can be made uniform. Moreover, the flatness of the current line formed in the vicinity of the magnetoresistive effect element while being separated from the magnetoresistive effect element is improved.

(Embodiment 1)
(Production method)
With reference to FIGS. 1-13, the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention is demonstrated.

  The method of manufacturing a magnetic sensor device in the present embodiment includes a step of forming a magnetoresistive effect element on the upper surface of a substrate via a first insulating layer, and a step of forming a barrier layer covering the upper side of the magnetoresistive effect element. Forming a sacrificial layer pattern having an opening above the barrier layer; forming a metal film so as to cover the sacrificial layer pattern; and selectively isotropically etching the metal film. An eaves-shaped portion forming step in which the metal film pattern covers the upper side of the sacrificial layer pattern and remains only as an eaves-shaped portion that protrudes around the metal film pattern, and does not remain at the bottom of the opening, Forming a conductive layer so as to be deposited from above on the metal film pattern above the sacrificial layer pattern and on the bottom of the opening; and By removed by the metal layer pattern and the conductive layer was collectively removed in the upper side of the metal film pattern, and a conductive layer patterning step to leave the conductive layer at the bottom of the opening. This will be described in detail below.

  FIG. 1 shows a plan view of a magnetic sensor device that can be obtained by the method of manufacturing a magnetic sensor device in the present embodiment. Actually, four such magnetic sensor devices having a meander-like folded structure are combined to form a Wheatstone bridge, which is used for magnetic detection. 1 corresponds to one of the four sides.

  This magnetic sensor device includes a conductive portion 12. FIG. 2 shows a cross-sectional view taken along the line II-II in FIG. A magnetic sensor device in the present embodiment, that is, a manufacturing method until obtaining the structure shown in FIG. 2 will be described.

(Process of forming magnetoresistive effect element)
First, a “step of forming a magnetoresistive element” is performed. As shown in FIG. 3, the magnetoresistive effect element 1 is formed on the silicon substrate 2 via the silicon thermal oxide layer 3 and the silicon nitride layer 4. FIG. 3 is a cross-sectional view of the same position as in FIG. Although the silicon substrate 2 is the substrate on which the magnetoresistive effect element 1 is installed, the substrate is not limited to this as long as insulation is ensured and the surface has a smooth surface without unevenness. For example, a glass substrate may be used in place of the silicon substrate 2. The silicon thermal oxide layer 3 and the silicon nitride layer 4 are provided together as a first insulating layer. Since the magnetoresistive effect element 1 is used as a magnetic sensor device in practical use, for example, in a thinned bridge structure, in order to leave only a desired part after depositing the material of the magnetoresistive effect element 1 over a wide range. Patterning is performed. As the magnetoresistive element 1, for example, a thin film having a thickness of about 20 nm to 50 nm containing nickel, iron or the like as a main component is used. However, the present invention is not limited to this. The silicon thermal oxide layer 3 and the silicon nitride layer 4 are layers for electrically insulating the silicon substrate 2 and the magnetoresistive element 1. Among these insulating layers, the silicon thermal oxide layer 3 may be formed by a CVD (Chemical Vapor Deposition) method or the like, but it is desirable to use a thermal oxide layer as the silicon thermal oxide layer 3. . This is because the thermal oxide layer is known to exhibit a good withstand voltage.

(Step of forming a barrier layer)
Next, a “step of forming a barrier layer” is performed. That is, a tantalum nitride layer 5 as a barrier layer is deposited on the magnetoresistive effect element 1. Thereafter, the magnetoresistive effect element 1 and the tantalum nitride layer 5 are patterned so as to have a desired length, width and number. FIG. 3 shows a cross section of one magnetoresistive element 1 only in the longitudinal direction. In this embodiment, the tantalum nitride layer 5 is provided as a barrier layer. However, the present invention is not limited to this, and the barrier layer may be omitted.

(Process of forming a sacrificial layer pattern)
Next, a “step of forming a sacrificial layer pattern” is performed. As shown in FIGS. 4 and 5, a silicon oxide layer 7 is formed as a sacrificial layer pattern. However, the silicon oxide layer 7 is provided with a plurality of openings 6. FIG. 5 is a cross-sectional view taken along line VV in FIG. The opening 6 formed at this time is also referred to as a “first opening”. In forming these, a process of depositing the silicon oxide layer 7 on the entire surface and a process of patterning the silicon oxide layer 7 to provide the opening 6 are performed. Thus, the silicon oxide layer 7 having a desired pattern is obtained, and at the same time, an opening 6 serving as a conductive portion window is formed after a desired width. The conductive part window is an opening that appears in the conductive layer later. The opening 6 opened in the silicon oxide layer 7 is used later as a source for providing a conductive portion window in the conductive layer.

  The width of the opening 6 is larger than the width of the opening (second opening) 9 formed later and the width of the conductive portion. In FIGS. 4 and 5, the three first openings 6 are schematically shown with arbitrary widths and intervals for simplification, but in actuality, the width of the first openings 6 is a thinned magnetoresistive resistor. It is determined by the width of the effect element 1 and the performance as a magnetic sensor device, and is not limited to the examples shown in FIGS. However, the silicon oxide layer 7 needs to be formed of a heat-resistant material in order to prevent thermal deterioration during thick film deposition in a later step.

(Process of forming metal film)
Next, “a step of forming a metal film” is performed. That is, as shown in FIG. 6, the metal film 8 is deposited. The silicon oxide layer 7 as a sacrificial layer pattern is covered with a metal film 8. The metal film 8 is deposited not only on the silicon oxide layer 7 but also on the tantalum nitride layer 5 as a barrier layer inside the opening 6. The metal film 8 is deposited on the silicon nitride layer 4 in the portion where the silicon nitride layer 4 as the uppermost layer of the first insulating layer is directly exposed regardless of the inside or outside of the opening 6. The

  The metal film 8 needs to be a material that isotropically etched in the next step. Further, it is necessary to use a heat resistant material in order to prevent thermal degradation when depositing a thick film in the subsequent process. The material of the metal film 8 may be aluminum, for example. The metal film 8 may be formed by sputtering or the like.

(Eave shape forming process)
Next, the “eave shape portion forming step” is performed. That is, the structure shown in FIG. 7 is obtained through a photoresist coating process, a photoresist patterning process, and a selective isotropic etching process of the metal film 8 (see FIG. 6). The metal film 8 becomes a metal film pattern. This metal film pattern remains only as an eaves-shaped portion 10 that covers the upper side of the silicon oxide layer 7 as a sacrificial layer pattern and projects around the silicon oxide layer 7. On the other hand, the metal film 8 does not remain at the bottom of the opening 6.

  In this way, the 2nd opening part 9 and the eaves-shaped part 10 are formed. The eaves-shaped portion 10 is formed by adjusting the second opening 9 so as to have a desired width. As shown in FIG. 7, the second opening 9 is formed over the first opening 6. The width of the second opening 9 is formed smaller than the width of the first opening 6.

  Therefore, the eaves-shaped portion 10 formed on the upper side of the silicon oxide layer 7 as a result of the isotropic etching has an undercut shape controlled with higher accuracy than the conventional lift-off process. As a result, there is an effect of significantly reducing the frequency of occurrence of burrs.

  The width of the second opening 9 can be adjusted by the photoresist patterning process, the thickness of the metal film 8, and the etching process. Specific examples are shown below. As shown in FIG. 8, an oxide film as the silicon oxide layer 7 is deposited by 2.3 μm, and the window as the first opening 6 is etched. When an aluminum film as the metal film 8 is deposited thereon by 2 μm as shown in FIG. 9, the slope of the step of the aluminum film appears at a location of about 1 μm from the end of the oxide film. As shown in FIG. 10, patterning is performed at the lower end of the step of the aluminum film. That is, a resist film 17 is provided. By doing so, the eaves shape can be formed to extend from the end of the oxide film to a place of 1 μm. In the two-layer resist method in Patent Document 3 described above, the undercut amount is about 0.1 μm at most, but in this embodiment, a very large step can be formed as compared with that. Further, in the etching of the aluminum film, when the etching is performed on the sloped portion of the step as shown in FIG. 12, compared with the case where the flat film is etched in the lateral direction as shown in FIG. Since the advancing direction is obliquely upward, the change in the position of the etching edge is less affected by the etching time, and the window can be formed with high accuracy.

(Process for forming a conductive layer)
Next, a “process for forming a conductive layer” is performed. That is, the conductive layer 11 is deposited on the entire surface of the structure shown in FIG. Thus, the structure shown in FIG. 13 is obtained. As shown in the figure, the conductive layer 11 is deposited on the exposed upper surfaces of the silicon nitride layer 4 and the tantalum nitride layer 5 and on the upper surface and slope of the eaves-shaped portion 10.

  The conductive layer 11 only needs to be formed of an electrically conductive material, and desirably has a low resistance. Examples of materials that can be used as the material of the conductive layer 11 include gold. The conductive layer 11 can be formed by sputtering or the like. In order to improve adhesion, diffusion prevention, etc., it is preferable to form a film on chromium, titanium or the like instead of a single layer, or to form a film sandwiched between chromium or titanium.

  In order to reduce the resistance value, the thickness of the conductive layer 11 should be as thick as possible, and it is desirable to form a film with a thickness of several thousand Å. When the conductive layer 11 is formed in a thick film, if the lower deposition layer is a resist, there is a problem that a residue remains at the time of removal in the next process due to thermal deterioration. Therefore, the deposition layer located below the conductive layer 11 is A silicon oxide film or metal film with high heat resistance is desirable.

(Conductive layer patterning process)
Next, a “conductive layer patterning step” is performed. That is, by removing the silicon oxide layer 7 as a sacrificial layer pattern by etching, the eaves-shaped portion 10 that was the metal film pattern and the conductive layer 11 thereabove are removed together, and the bottom of the opening 6 is formed. A certain conductive layer 11 is left as the conductive portion 12. Thus, the structure shown in FIG. 2 is obtained.

  In setting the etching conditions, it is necessary to make the etching rate of the silicon oxide film 7 faster than the etching rates of the silicon nitride layer 4, the tantalum nitride layer 5, and the conductive layer 11. Also, it is desirable that the etching rate is high for the metal film 8. As an etching solution that satisfies these conditions, hydrofluoric acid is desirable, but not limited thereto.

  After the etching process performed as the conductive layer patterning process, the conductive layer 11 remaining on the magnetoresistive effect element 1 via the tantalum nitride layer 5 becomes the conductive portion 12. The conductive part 12 may be called a “BBP (Barber Pole) electrode”. Further, mainly at the end of the magnetoresistive effect element 1, the residue of the conductive layer 11 becomes a connection current line 13 for connecting to another magnetoresistive effect element 1, input / output pads, and the like.

  The width of the conductive portion 12 related to the performance as a magnetic sensor device described later is defined by the width of the second opening 9. Therefore, the width of the conductive portion 12 is determined by the process of forming the second opening 9.

  Preferably, the magnetoresistive effect element 1 has a center line 18 as shown in FIG. 1 in the step of forming the conductive layer and the step of patterning the conductive layer. A plurality of strips arranged at regular intervals along the center line 18 in a direction in which the conductive layer, that is, the conductive part 12 remaining at the bottom of the opening 6 obliquely intersects the center line 18 at a constant angle. Formed as a pattern. By forming in this way, a barber pole structure can be obtained reliably.

(Description of current path)
FIG. 14 is an explanatory diagram of a current path flowing through the magnetic sensor device. In the figure, the conductive portion 12 is provided with an inclination of 45 ° with respect to the thinned axial direction of the magnetoresistive effect element 1. The magnetic sensor device is used in a state where a current is applied in the direction shown in the figure. The conductive portion 12 is provided to incline the direction of the current flowing through the surface of the magnetoresistive effect element 1 by 45 °. The potentials are equal in each conductive portion 12, and current flows perpendicularly to the conductive portion 12. When the magnetoresistive effect element 1 which is a ferromagnetic material is magnetized in the axial direction, the angle θ formed by the magnetization direction and the current direction when the external magnetic field is zero can be set to 45 °.

(Action / Effect)
When the magnetic sensor device is formed with a bridge structure composed of the magnetoresistive effect elements 1 which are thinned on the four sides, the resistance of each of the magnetoresistive effect elements 1 on the four sides is the same, the balance is maintained, and the external magnetic field is zero. In this case, it is desirable that the bridge output is 0, that is, the offset is 0. In order for the resistances of the magnetoresistive elements 1 constituting the four sides to be the same, in the manufacturing process, the uniform conductive portion 12 is formed, that is, the conductive portion 12 is formed to have a uniform width. It becomes important.

  As described above, according to the manufacturing method of the magnetic sensor device in the present embodiment, the step and unevenness of the element surface having the conductive portion is reduced, so that the shape of the conductive portion can be realized with high accuracy. It can be uniform. Moreover, the flatness of the current line formed in the vicinity of the magnetoresistive effect element while being separated from the magnetoresistive effect element is improved. In this way, improvement in performance as a magnetic sensor device is realized.

(Embodiment 2)
A method for manufacturing a magnetic sensor device according to the second embodiment of the present invention will be described with reference to FIGS. In the method for manufacturing a magnetic sensor device in the present embodiment, after the conductive layer patterning step, a step of forming the second insulating layer 14 so as to collectively cover the conductive portion 12 and the magnetoresistive effect element 1; A step of disposing a current line 15 made of a conductor on the upper side of the second insulating layer 14. The current line 15 is arranged so that the center line of the current line 15 coincides with the center line 18 of the magnetoresistive effect element 1 when viewed in plan.

  That is, after the conductive portion 12 is manufactured by the manufacturing method described in the first embodiment, the magnetoresistive effect element 1 and the plurality of strip-shaped conductive portions 12 are collectively formed as shown in FIG. Then, an insulating layer 14 is provided so as to cover it. Further, a current line 15 and a protective film 16 are deposited so as to cover the insulating layer 14 as shown in FIG. FIG. 17 shows a cross-sectional view taken along the line XVII-XVII in FIG.

  The insulating layer 14 and the protective film 16 are preferably made of a material that is electrically insulative and that protects the magnetoresistive effect element 1 and the conductive portion 12 installed in the lower layer from the external environment. Therefore, it can be formed of a silicon oxide film, a silicon nitride film, or the like, but is not limited to these materials. Note that both the insulating layer 14 and the protective film 16 are desirably dense and have good adhesion.

  The current line 15 is used to apply a magnetic field generated by the current applied to the current line 15 to the magnetoresistive effect element 1, and in particular, a measured current line or a measured current line for measuring a weak current. Is used as a compensation current line for applying a compensation magnetic field when it is provided outside the magnetic sensor device. Further, in order to apply a uniform and large magnetic field from the current line 15 to the magnetoresistive effect element 1, the current line 15 is as close to the magnetoresistive effect element 1 as possible with a flat current line 15 with few irregularities. It is desirable that the center line of the magnetoresistive effect element 1 and the center line of the current line 15 coincide with each other. The material of the current line 15 can be selected from, for example, low resistance material such as aluminum or gold, but is not limited thereto. Furthermore, in order to increase the magnetic field applied to the magnetoresistive effect element 1 under the conditions of the same current density and the same insulating layer thickness, in the rectangular cross-sectional shape of the current line 15, the ratio of the vertical width to the horizontal width, that is, the vertical width It is desirable to increase the width / width value. The value of the vertical width / horizontal width is a value obtained by dividing the thickness by the horizontal width.

  Furthermore, in the present embodiment, it is preferable that the current line is formed so that a cross-sectional shape of the current line is a rectangle and a value obtained by dividing the thickness by the lateral width is 0.1 or more. FIG. 18 is a graph showing the relationship between the applied magnetic field ratio and the vertical width / horizontal width value when the thickness of the insulating layer 14 between the magnetoresistive element 1 and the current line 15 is 0.3 μm. FIG. 18 shows that the applied magnetic field ratio increases as the value of the vertical width / horizontal width increases, and the applied magnetic field ratio decreases rapidly when the vertical width / horizontal width becomes 0.1 or less. From this, it can be said that the value of the vertical / horizontal width of the current line is desirably 0.1 or more.

(Action / Effect)
As described above, according to the present embodiment, the method includes the step of depositing the current lines 15 and the like after the manufacturing method according to the first embodiment is completed. A magnetic sensor device capable of applying a uniform magnetic field from the few flat current lines 15 toward the magnetoresistive effect element 1 is obtained. Further, by forming the current line so as to increase the vertical width / width in the rectangular cross-sectional shape of the current line, a magnetic sensor device in which the magnetic field applied to the magnetoresistive effect element 1 is increased can be obtained.

  In addition, the said embodiment disclosed this time is an illustration in all the points, Comprising: It is not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and includes all modifications within the scope and meaning equivalent to the terms of the claims.

It is a top view of the magnetic sensor device which can be obtained with the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is arrow sectional drawing regarding the II-II line | wire in FIG. It is sectional drawing in the 1st process of the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is a top view in the 2nd process of the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is arrow sectional drawing regarding the VV line in FIG. It is sectional drawing in the 3rd process of the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is sectional drawing in the 4th process of the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is 1st explanatory drawing of a mode that the width | variety of a 2nd opening part is adjusted with an etching process in Embodiment 1 based on this invention. It is 2nd explanatory drawing of a mode that the width | variety of a 2nd opening part is adjusted with an etching process in Embodiment 1 based on this invention. It is 3rd explanatory drawing of a mode that the width | variety of a 2nd opening part is adjusted with an etching process in Embodiment 1 based on this invention. It is the 1st explanatory view about the direction where etching progresses in Embodiment 1 based on the present invention. It is the 2nd explanatory view about the direction which etching advances in Embodiment 1 based on the present invention. It is sectional drawing in the 5th process of the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is explanatory drawing of the electric current path which flows into the magnetic sensor device obtained with the manufacturing method of the magnetic sensor device in Embodiment 1 based on this invention. It is sectional drawing in the 1st process of the manufacturing method of the magnetic sensor device in Embodiment 2 based on this invention. It is sectional drawing in the 2nd process of the manufacturing method of the magnetic sensor device in Embodiment 2 based on this invention. It is arrow sectional drawing regarding the XVII-XVII line | wire in FIG. It is a graph which shows the relationship of the applied magnetic field ratio with respect to the value of length / width.

Explanation of symbols

  1 magnetoresistive effect element, 2 silicon substrate, 3 silicon thermal oxide layer, 4 silicon nitride layer, 5 tantalum nitride layer, 6 (first) opening, 7 silicon oxide layer, 8 metal film, 9 second Opening portion, 10 eaves-shaped portion, 11 conductive layer, 12 conductive portion, 13 connection current line, 14 second insulating layer, 15 current line, 17 resist film, 18 center line (of magnetoresistive effect element).

Claims (4)

Forming a magnetoresistive element on the upper surface of the substrate via the first insulating layer;
Forming a barrier layer overlying the magnetoresistive element;
Forming a sacrificial layer pattern having an opening on the barrier layer;
Forming a metal film to cover the sacrificial layer pattern;
By isotropically etching the metal film, a portion of the metal film at the bottom of the opening is removed, and a portion covering the upper side of the sacrificial layer pattern and a portion protruding around the portion are selectively left. Process,
Forming a conductive layer so as to be deposited from above on the metal film pattern above the sacrificial layer pattern and on the bottom of the opening;
A conductive layer patterning step of removing the sacrificial layer pattern and removing the metal film pattern and the conductive layer above the metal film pattern all together, leaving the conductive layer at the bottom of the opening; A method for manufacturing a magnetic sensor device.   In the step of forming the conductive layer and the conductive layer patterning step, the conductive layer remaining at the bottom of the opening is in a direction that obliquely intersects the center line of the magnetoresistive element at a certain angle. The method of manufacturing a magnetic sensor device according to claim 1, wherein the magnetic sensor device is formed as a plurality of strip-like patterns arranged at regular intervals along the center line. After the conductive layer patterning step, forming a second insulating layer so as to collectively cover the conductive layer and the magnetoresistive element; and
Disposing a current line made of a conductor on the upper side of the second insulating layer,
3. The magnetic sensor device according to claim 1, wherein the current line is disposed so that a center line of the current line substantially coincides with a center line of the magnetoresistive element when viewed in plan. Method.   4. The method of manufacturing a magnetic sensor device according to claim 3, wherein the current line is formed so that a cross-sectional shape of the current line is a rectangle and a value obtained by dividing a thickness by a width is 0.1 or more.

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