WO2006057379A1

WO2006057379A1 - Thin film magnetic resistor element and method for manufacturing it, and magnetic sensor using thin film magnetic resistor element

Info

Publication number: WO2006057379A1
Application number: PCT/JP2005/021767
Authority: WO
Inventors: Yuko Takahashi; Hirofumi Fukui; Takafumi Hatanai; Takuo Ito; Nobukiyo Kobayashi; Kiwamu Shirakawa; Susumu Murakami
Original assignee: Alps Electric Co., Ltd.; The Research Institute For Electric And Magnetic Materials
Priority date: 2004-11-29
Filing date: 2005-11-28
Publication date: 2006-06-01
Also published as: JP4953569B2; JP2006156661A

Abstract

[PROBLEMS] To provide a thin film magnetic resistor element having high magnetic field sensitivity and excellent linearity, to provide a method for manufacturing the thin film magnetic resistor element at low cost and easily, and to provide a practical magnetic sensor using the thin film magnetic resistor element. [MEANS FOR SOLVING PROBLEMS] The thin film magnetic resistor element (1A) is composed of an insulating board (2); strip-shaped first soft magnetic film (3) and second soft magnetic film (4), which are formed on the insulating board (2) with their one edge arranged to face each other through a prescribed gap (g); nonmagnetic insulating films (5) formed on a portion close to the gap (g) on an upper lane of the first soft magnetic film (3), and on a portion close to the gap (g) on an upper plane of the second soft magnetic film (4), respectively; and a huge magnetic resistor thin film (6) formed on the insulating board (2) in the gap (g), on the edge planes of the first and second soft magnetic films (3, 4) facing the gap (g), and on the edge plane of the nonmagnetic insulating films (5) continued from the soft magnetic film edge planes and on a part of an upper lane of the nonmagnetic insulating film.

Description

Thin film magnetoresistive element, manufacturing method thereof, and magnetic sensor using thin film magnetoresistive element

Technical field

The present invention relates to a thin film magnetoresistive element comprising a giant magnetoresistive thin film in a gap portion of a soft magnetic film, a method of manufacturing the same, and a magnetic sensor using the thin film magnetoresistive element. Background art

Conventionally, as a thin film magnetoresistive element having a magnetoresistance effect much higher than that using a permalloy alloy etc. and having a high magnetic field sensitivity, as shown in FIG. The two soft magnetic films 101 and 102 are disposed opposite to each other with the required gap 103, and in the gap 103 and on a part of the upper surface of the soft magnetic film 101 and 102 following this, for example, a nano-Dara-ura alloy thin film etc. It is proposed that the giant magnetoresistive thin film 104 of the above is formed (see, for example, Patent Document 1).

This thin film magnetoresistive element has a gap length Lg of not more than 20 times the film thickness of the soft magnetic films 101 and 102 so that when the soft magnetic films 101 and 102 are magnetized, they enter the gap 103. Since a magnetic field corresponding to the magnetic field of the soft magnetic films 101 and 102 can be applied to the giant magnetoresistance thin film 104 disposed, the magnetoresistance effect (MR ratio) of the giant magnetoresistance thin film 104 can be reduced with a small external magnetic field. It can be saturated and the magnetic field sensitivity can be significantly increased.

[0004] As described above, since this thin film magnetoresistive element can extremely increase not only the MR ratio but also the magnetic field sensitivity, a magnetic head (MR head which enables high speed and high density recording magnetic recording) It can be applied to magnetic sensors (MR sensors) in servo motors or rotary encoders that enable high-resolution signal detection.

Patent Document 1: Patent No. 3466470

Disclosure of the invention

Problem that invention tries to solve

By the way, in order to obtain the above-described effects, it is necessary to cause the large magnetoresistive thin film 104 to effectively act on the magnetic field flowing from the soft magnetic films 101 and 102. That is, this giant magnetoresistive thin film Electrical resistance of 104 is sufficiently larger than the electrical resistance of the soft magnetic film 101, 102 (1 X 1 0 4 μ Ω ' «11~1 10 9 Ω' cm) , the current of this device, the gap It flows through the giant magnetoresistance thin film 104 between 103. Therefore, it is necessary to effectively apply a magnetic field to the giant magnetoresistive thin film 104 in the gap 103.

Incidentally, in the thin film magnetoresistive element having the above configuration, the giant magnetoresistive thin film 104 is formed not only in the gap 103 but also on a part of the upper surface of the soft magnetic films 101 and 102. Therefore, the electric path and magnetic path from the soft magnetic film 101 to the soft magnetic film 102 through the giant magnetoresistive thin film 104 are formed in the gap 103 as well as the end face force of the soft magnetic film 101 as shown in FIG. The path to the end face of the soft magnetic film 102 through the resistive thin film 104 and the upper surface force of the soft magnetic film 101 also to the top surface of the soft magnetic film 102 through the giant magnetoresistive thin film 104 formed outside the gap 103 Distributed to

For this reason, the thin film magnetoresistive element having the above-described configuration has a single magnetic flux path, as the magnetic flux density of the magnetic flux passing through the giant magnetoresistive thin film 104 decreases and its path length becomes nonuniform. The magnetic field sensitivity is reduced compared to In addition, since the magnetic field sensitivity of the thin film magnetoresistive element is a combined value of the local magnetic field sensitivity in each path, the linearity of the magnetic field sensitivity is deteriorated as compared with the thin film magnetoresistive element having a single magnetic flux path. Therefore, since the magnetic field does not effectively apply to the gap 103 through which most of the current flows, the degree of the MR effect particularly in the case of a weak magnetic field is reduced.

The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a thin film magnetoresistive element having high magnetic field sensitivity and good linearity. And providing a method for inexpensively and easily manufacturing such a thin film magnetoresistive element, and providing a practical magnetic sensor using the thin film magnetoresistive element.

Means to solve the problem

In order to solve the above-mentioned problems, the present invention provides a giant magnetoresistive thin film, and first and second soft magnetic films whose one ends are electrically and magnetically connected via the giant magnetoresistive thin film. A nonmagnetic insulating film interposed between at least one of the first soft magnetic film and the second soft magnetic film and the giant magnetoresistive thin film, the nonmagnetic insulating film being the giant nonmagnetic insulating film Magnetism The electric path and magnetic path extending from the first soft magnetic film to the second soft magnetic film through the large magnetoresistance thin film are located at positions where the contact area with the soft magnetic film facing the resistive thin film is narrowed. The first and second soft magnetic films are regulated in one direction, and terminal portions for signal detection are provided.

Thus, the nonmagnetic insulating film is interposed in the required portion between the first and second soft magnetic films and the giant magnetoresistive thin film, and from the first soft magnetic film through the giant magnetoresistive thin film By restricting the electric path and the magnetic path leading to the second soft magnetic film in one direction, it is possible to suppress the dispersion of the magnetic flux and the non-uniformity of the magnetic flux path length, thereby improving the sensitivity of the magnetic field and its linearity. it can. In addition, since the path of the magnetic flux and the path of the current coincide with each other, the MR effect can be effectively exhibited even in a weak magnetic field.

Further, according to the present invention, in the thin film magnetoresistive element having the above configuration, the end faces of the first and second soft magnetic films are disposed opposite to each other through a required gap, and the first and second soft magnetic films are provided. A nonmagnetic insulating film is formed on the upper surface of the soft magnetic film, and the giant magnetoresistive thin film is formed in and around the gap, and the nonmagnetic insulating film causes the giant magnetoresistive thin film to pass through the giant magnetoresistive thin film. An electric path and a magnetic path from the (1) soft magnetic film to the second soft magnetic film are restricted only in the arrangement direction of the first soft magnetic film and the second soft magnetic film.

According to the configuration, the nonmagnetic insulating film is formed on the upper surface of the first and second soft magnetic films, respectively, so that the upper surface of the first soft magnetic film and the giant magnetoresistive thin film are interposed. Since the electric path and magnetic path leading to the upper surface of the second soft magnetic film can be cut off, the electric path and magnetic path extending from the first soft magnetic film to the ^second soft magnetic film via the giant magnetoresistive thin film It can be regulated only in the alignment direction of the film and the ^second soft magnetic film.

Further, according to the present invention, in the thin film magnetoresistive element having the above configuration, the nonmagnetic insulating film is stacked on the giant magnetoresistive thin film with its end faces aligned, and the first soft magnetic film is one of the above. The second soft magnetic film is formed so as to cover the end face and a part of the nonmagnetic insulating film, and the second soft magnetic film is formed so as to cover the other end face and a part of the nonmagnetic insulating film. An electric path and a magnetic path from the first soft magnetic film to the second soft magnetic film via the giant magnetoresistive thin film are restricted only in the stacking surface direction of the giant magnetoresistive thin film. did.

[0014] Also according to the configuration, an electric path and a magnetic path extending from the first soft magnetic film to the second soft magnetic film via the giant magnetoresistive thin film are formed by the nonmagnetic insulating film stacked on the giant magnetoresistive thin film. It can be regulated only in the direction of the end face of the giant magnetoresistive thin film.

Further, in the thin film magnetoresistive element having the above configuration according to the present invention, the nonmagnetic insulating film is formed on the upper surface of the first soft magnetic film, and the upper surface and end surface of the nonmagnetic insulating film; The giant magnetoresistive thin film is formed on the end face of the soft magnetic film, and one end is in contact with the end of the nonmagnetic insulating film and the giant magnetoresistive thin film formed on the end face of the first soft magnetic film. A second soft magnetic film is formed, and an electric path and a magnetic path from the first soft magnetic film to the second soft magnetic film via the giant magnetic resistance thin film by the nonmagnetic insulating film are referred to as the first soft magnetic film. And the second soft magnetic film is regulated only in the arrangement direction.

According to the configuration, the nonmagnetic insulating film is formed on the upper surface of the first soft magnetic film, and the second soft magnetic film is formed on the end face side of the first soft magnetic film via the giant magnetic resistance thin film. By forming the first soft magnetic film, the electric path and magnetic path leading to the second soft magnetic film can be cut off through the upper surface of the first soft magnetic film and the giant magnetoresistive thin film. The electric path and magnetic path leading to the second soft magnetic film via the thin film can be regulated only in the arrangement direction of the first soft magnetic film and the second soft magnetic film.

Further, according to the present invention, in the thin film magnetoresistive element having the above configuration, the second soft magnetic film is stacked on the nonmagnetic insulating film formed such that one end thereof is in contact with the giant magnetoresistive thin film. Was configured.

According to the configuration as described above, by laminating the second soft magnetic film on the nonmagnetic insulating film, the end surface of the first soft magnetic film and the end surface of the second soft magnetic film are made of the giant magnetoresistive thin film. The electric path and magnetic path from the first soft magnetic film to the second soft magnetic film via the giant magnetoresistive thin film can be restricted only in the film thickness direction of the giant magnetoresistive thin film. it can.

Further, according to the present invention, in the thin film magnetoresistive element having the above configuration, the giant magnetoresistive thin film is formed on a part of the upper surface of the first soft magnetic film, and the upper surface and the end surface of the first soft magnetic film In addition, the nonmagnetic insulating film is formed on the outer peripheral portion and the end face of the upper surface of the giant magnetoresistive thin film. Forming the second soft magnetic film so that the lower surface of one end portion is in contact with the giant magnetic resistance thin film exposed from the nonmagnetic insulating film, and the nonmagnetic insulating film forms the giant magnetoresistive thin film An electric path and a magnetic path from the first soft magnetic film to the second soft magnetic film via the first magnetic film are restricted only in the film thickness direction of the giant magnetoresistive thin film.

According to the configuration, one end of the second soft magnetic film is stacked on the upper surface of the first soft magnetic film via the giant magnetoresistive thin film, and the end face of the first soft magnetic film and the second soft magnetic film By interposing a nonmagnetic insulating film between the end face of the film and between the end face of the giant magnetoresistive thin film and the end face of the second soft magnetic film, the end face force of the first soft magnetic film Since the electric path and magnetic path leading to the end face of the second soft magnetic film can be cut off via the upper surface of the first soft magnetic film and the giant magnetoresistance thin film on the electric path and magnetic path alignment leading to the end face, The electrical path and magnetic path from the magnetic film to the second soft magnetic film via the giant magnetoresistive thin film can be restricted only in the film thickness direction of the giant magnetoresistive thin film.

Further, according to the present invention, in the thin film magnetoresistive element having the above-described configuration, the giant magnetoresistive thin film is formed to have a magnetic nonmagnetic film formed by dispersing ferromagnetic fine particles in an insulator matrix. Was configured.

Since the Dara-Yura magnetic film has a much larger MR ratio than a giant magnetoresistance thin film of an alloy such as Permalloy alloy, the use of the Dara-Yura magnetic film as the giant magnetoresistance thin film The output signal strength of the magnetic head and the magnetic sensor can be increased. In addition, since a large MR ratio can be obtained with a single layer of a magnetic film with a single layer, the manufacture of a thin film magnetoresistive element can be facilitated as compared with the case of using a giant magnetoresistive thin film having a multilayer structure.

Further, in the thin film magnetoresistive element having the above configuration according to the present invention, the thickness of the giant magnetoresistive thin film formed between the first soft magnetic film and the second soft magnetic film is 0. It was configured to be more than 05 μm and less than 1.0 m.

According to the research of the inventors of the present invention, a gap is formed in the soft magnetic film formed on the substrate by ion beam etching or the like, and then, the giant magnetic resistance thin film is sputtered in the formed gap. In the case where the gap length is 1 m or less, the wraparound of the giant magnetoresistive thin film into the gap becomes insufficient, and uniform giant magnetoresistive thin film is formed. Will be difficult. On the other hand, when the thin film magnetoresistive element is formed of a laminate of the first and second soft magnetic films, the giant magnetoresistive thin film, and the nonmagnetic insulating film, the gap length is not limited in manufacturing. The thickness of the giant magnetic resistance thin film formed between the first soft magnetic film and the second soft magnetic film can be formed to be not less than 0.05 m and not more than 1.0 m. Therefore, the gap length of the thin film magnetoresistive element can be substantially reduced, and the magnetic field sensitivity of the thin film magnetoresistive element can be enhanced.

Further, in order to solve the above-mentioned problems, the present invention adopts the following configurations as a method of manufacturing a thin film magnetoresistive element.

(1) A step of forming a first soft magnetic film and a second soft magnetic film opposite to each other through a required gap on an insulating substrate, an upper surface of the first soft magnetic film, and the second soft. A thin film magnetoresistive element is manufactured by the steps of: forming a nonmagnetic insulating film on the upper surface of the magnetic film; and forming a giant magnetoresistive thin film on the upper surface and end face of the nonmagnetic insulating film in the gap. Thereby, the thin film magnetoresistive element according to claim 2 is obtained.

(2) A step of forming a first soft magnetic film on an insulating substrate, a step of forming a nonmagnetic insulating film on the upper surface of the first soft magnetic film, and one end face of the first soft magnetic film And a step of forming a giant magnetoresistive thin film on the insulating substrate following the one end surface and the upper surface of the nonmagnetic insulating film and the one end surface of the first soft magnetic film, and one end on the insulating substrate Forming a second soft magnetic film in contact with the end surface of the nonmagnetic insulating film, the end surface of the first soft magnetic film, and the giant magnetoresistive thin film formed on the insulating substrate; Manufacture. Thereby, a thin film magnetoresistive element according to claim 3 is obtained.

(3) A step of forming a first soft magnetic film on an insulating substrate, a step of forming a giant magnetoresistive thin film near one end of the upper surface of the first soft magnetic film, and a step of forming the first soft magnetic film Forming a nonmagnetic insulating film on the upper surface and the end surface and part of the upper surface of the giant magnetoresistive thin film following it, and one end surface of the first soft magnetic film, and one end of the nonmagnetic insulating film on the insulating substrate Forming a second soft magnetic film in contact with the more exposed giant magnetoresistive thin film, thereby manufacturing a thin film magnetoresistive element. Thereby, the thin film magnetoresistive element according to claim 4 is obtained.

Further, in order to solve the above problems, the present invention relates to a giant magnetic sensor for a magnetic sensor. A resistive thin film, first and second soft magnetic films electrically and magnetically connected at one end via the giant magnetoresistive thin film, at least a surface of the first soft magnetic film, and the second soft magnetic film A nonmagnetic insulating film which is formed on any one of the surfaces of the first magnetic film and which extends from the first soft magnetic film to the second soft magnetic film via the giant magnetoresistive thin film in one direction. A bridge comprising: two thin film magnetoresistive elements having terminal portions for signal detection on the first and second soft magnetic films on two opposing sides and a fixed resistive element on the other two opposing sides It was also configured to be circuit power.

As described above, a thin film magnetoresistive element in which the electric path and the magnetic path from the first soft magnetic film to the second soft magnetic film via the giant magnetoresistive thin film are regulated by the nonmagnetic insulating film in the − direction is provided. Since magnetic flux dispersion and magnetic flux path length unevenness can be suppressed, a magnetic sensor having high magnetic field sensitivity and excellent linearity can be obtained. In addition, when a magnetic sensor is configured to have a bridge circuit having two thin film magnetoresistive elements on two opposing sides and a fixed resistance element on the other two opposing sides, the thin film magnetoresistive element is formed by the null method. The fluctuation of the acting magnetic field can be detected, and the influence of the fluctuation of the power supply voltage and the input impedance and non-linearity of the detector can be eliminated, so that the magnetic field can be detected with high accuracy. Effect of the invention

In the thin film magnetoresistive element of the present invention, a nonmagnetic insulating film is interposed in a required portion between the first and second soft magnetic films and the giant magnetoresistive thin film, and the second magnetoresistive thin film is interposed between the first and second soft magnetic films. (1) By restricting the electric path and magnetic path from the soft magnetic film to the second soft magnetic film in one direction, it is possible to suppress the dispersion of the magnetic flux and the nonuniformity of the magnetic flux path length, and improve the magnetic field sensitivity and its linearity. Can. In addition, since the path of the magnetic flux and the path of the current coincide with each other, the MR effect can be effectively exhibited even in a weak magnetic field.

According to the method of manufacturing a thin film magnetoresistive element of the present invention, between the first soft magnetic film and the giant magnetoresistive thin film, between the second soft magnetic film and the giant magnetoresistive thin film, and the first soft magnetic film Since the step of forming the nonmagnetic insulating film in the required part between the second soft magnetic film and the second soft magnetic film is included, the electric path and the magnetic path from the first soft magnetic film to the second soft magnetic film through the giant magnetoresistive thin film The thin film magnetoresistive element regulated in the direction can be manufactured.

The magnetic sensor according to the present invention is characterized in that the first soft magnetic film is formed of the nonmagnetic insulating film via the giant magnetoresistive thin film. Since the electric path and magnetic path from the magnetic film to the second soft magnetic film are provided with the thin film magnetoresistive element in which the magnetic path is restricted in the − direction, dispersion of magnetic flux and unevenness of magnetic flux path length can be suppressed. A magnetic sensor having high linearity and excellent linearity can be obtained. In addition, when a magnetic sensor is configured with a bridge circuit having two thin film magnetoresistive elements on two opposing sides and a fixed resistance element on the other two opposing sides, the thin film magnetoresistive element acts on the thin film magnetoresistive element by the null method. The magnetic field fluctuation can be detected, and the influence of the fluctuation of the power supply voltage and the input impedance and nonlinearity of the detector can be removed, so that the magnetic field can be detected with high accuracy.

BEST MODE FOR CARRYING OUT THE INVENTION

A first embodiment of a thin film magnetoresistive element according to the present invention will be described based on FIGS. 1 and 2. FIG. FIG. 1 is a plan view of a thin film magnetoresistive element according to the first embodiment, and FIG. 2 is a sectional view taken along the line A-A of FIG.

As shown in FIG. 1 and FIG. 2 (a), the thin film magnetoresistive element 1A of this example is formed on the insulating substrate 2 and the insulating substrate 2, and one end is opposed via the required gap g. Of the upper surface of the first soft magnetic film 3 and the strip-like first soft magnetic film 3 and the second soft magnetic film 4 disposed near the gap g of the upper surface of the second soft magnetic film 4 The nonmagnetic insulating film 5 formed in each portion, the end faces of the first and second soft magnetic films 3 and 4 facing the gap g on the insulating substrate 2 in the gap g, and the nonmagnetic insulating film 5 subsequent thereto It is composed of a giant magnetoresistance thin film 6 formed on the end face and part of the top surface.

Insulating substrate 2 is formed in a desired shape and size with a high rigidity nonmagnetic insulator such as an inorganic dielectric, plastic or nonmagnetic ceramic.

As shown in FIG. 1, the first soft magnetic film 3 has a narrow width portion 3 a having a required gap width Wg, a wide width portion 3 b wider than the gap width Wg, and both of these portions 3 a, It consists of the taper part 3c which connects 3b. In addition, as shown in FIG. 1, the second soft magnetic film 4 has a narrow portion 4a having a required gap width Wg, a wide portion 4b wider than the gap width Wg, and both portions 4a, It consists of the taper part 4c which connects 4b. These first and second soft magnetic films 3 and 4 are made of Co Fe Si

77 5 9

Soft magnetic materials with high saturation magnetic flux density such as B alloy and Permalloy alloy (Fe Ni) as insulating base

8 65 35

The first and second soft magnetic films 3, 4 are formed by sputtering on the plate 2. Between the four, gap g of gap length force SLg is provided. The end faces of the narrow portions 3a and 4a may be formed perpendicular to the insulating substrate 2, but the formation of the giant magnetoresistive thin film 6 having a uniform thickness with respect to the end faces is facilitated and the end faces are formed on the end faces. In order to suppress the characteristic change of the giant magnetoresistance thin film 6, it is desirable to incline it at an inclination angle Θ t of 20 ° to 45 ° with respect to the perpendicular M made to the insulating substrate 2.

The nonmagnetic insulating film 5 electrically insulates between the upper surface of the first soft magnetic film 3 and the giant magnetoresistive thin film 6 and between the second soft magnetic film 4 and the giant magnetoresistive thin film 6. And SiO or A1

twenty two

It is formed by sputtering an inorganic dielectric such as O onto the first soft magnetic film 3.

3

As the giant magnetoresistive thin film 6 has a significantly larger MR ratio than a giant magnetoresistive thin film of an alloy system such as a permalloy alloy, and a large MR ratio can be obtained in one layer, the insulator matrix can be obtained. A magnetic film is formed by dispersing ferromagnetic particles therein. For example, 32 vol% of CoFe-MgF or Co Y 挙げ was cited as the magnetic film.

2 38. 6 14. 0 47. 4

Can be In the example shown in FIG. 2A, the giant magnetoresistive thin film 6 is formed on the insulating substrate 2 in the gap g, and the end faces of the first and second soft magnetic films 3 and 4 facing the gap g, and subsequent thereto. It is formed on a part of the end face and the top face of the nonmagnetic insulating film 5, but it is sufficient if it is formed on the end faces of at least the first soft magnetic film 3 and the second soft magnetic film 4. Alternatively, the giant magnetoresistive thin film 6 may be formed first, the gap g may be opened, and then the nonmagnetic insulating film 5 and the first and second soft magnetic films 3 and 4 may be formed.

As shown in FIG. 1, the thin film magnetoresistive element 1 A of this example has the nonmagnetic insulating film 5 of the wide portion 3 b of the first soft magnetic film 3 and the wide portion 4 b of the second soft magnetic film 4. The end portion that does not form a terminal for signal detection, and detects a magnetic signal in the direction from the first soft magnetic film 3 to the second soft magnetic film 4 via the giant magnetoresistive thin film 6 or in the opposite direction. Do.

In the thin film magnetoresistive element 1 A of this example, the nonmagnetic insulating film 5 is formed on the upper surfaces of the first and second soft magnetic films 3 and 4, respectively. The electric path and magnetic path leading to the upper surface of the second soft magnetic film 4 can be blocked via the giant magnetoresistive thin film 6, and as shown by the arrows in FIG. The electric path and magnetic path leading to the second soft magnetic film 4 via the resistive thin film 6 can be regulated only in the direction in which the first soft magnetic film 3 and the second soft magnetic film 4 are arranged. Therefore, the dispersion of the magnetic flux and the nonuniformity of the magnetic flux path length can be suppressed. The magnetic field sensitivity can be improved and the linearity thereof can be improved. Further, in the mode of FIG. 2B, the nonmagnetic insulating film 5 is formed on the giant magnetoresistive thin film 6. Also in this case, as shown by the arrows in the figure, the electric path and the magnetic path are restricted, and the same effect can be obtained.

Hereinafter, a method of manufacturing the thin film magnetoresistive element 1A according to the first embodiment will be described based on FIG. FIG. 3 is a flow chart showing the manufacturing procedure of the thin film magnetoresistive element 1A.

First, a soft magnetic film, which is the basis of the first soft magnetic film 3 and the second soft magnetic film 4, is formed to a uniform thickness on one surface of the insulating substrate 2 by plating or sputtering (procedure Sl) . Next, a photoresist layer is uniformly formed on the soft magnetic film, and a mask for forming a first soft magnetic film and a second soft magnetic film is formed through an exposure step and a development step (step S2). Next, the portion covered with the photoresist layer of the soft magnetic film is removed by etching, ion milling or the like, and thereafter, the remaining photoresist layer is removed (procedure S3). As a result, the first soft magnetic film 3 and the second soft magnetic film 4 are formed on one side of the insulating substrate 2 with one end facing the other through the required gap g. Next, the nonmagnetic insulating film 5 is formed by sputtering (Step S4), and the photoresist layer is uniformly formed again on the entire top surface of the insulating substrate 2 including the top surfaces of the first soft magnetic film 3 and the second soft magnetic film 4 After the exposure step and the development step, a mask for forming a nonmagnetic insulating film is formed (step S5). Next, the oxide film in the portion not covered with the photoresist layer is removed by etching or ion milling, and then the remaining photoresist layer is removed (procedure S6). Thereby, the nonmagnetic insulating film 5 is laminated on the upper surface of the first soft magnetic film 3 and the upper surface of the second soft magnetic film 4 respectively. Then, a giant magnetoresistive thin film 6 is deposited by sputtering (procedure S7), and after a photoresist layer is uniformly formed on the giant magnetoresistive thin film 6, the giant magnetoresistive thin film 6 is subjected to an exposure step and a development step. Form a mask (step S8). Next, the oxide film in the portion not covered with the photoresist layer is removed by etching or ion milling, and thereafter, the remaining photoresist layer is removed (procedure S9). Thereby, the thin film magnetoresistive element 1A according to the first embodiment shown in FIGS. 1 and 2 having the giant magnetoresistive thin film 6 in the gap g is obtained.

According to the manufacturing method of this example, nonmagnetic insulation is provided between the upper surface of the first soft magnetic film 3 and the giant magnetoresistive thin film 6 and between the upper surface of the second soft magnetic film 4 and the giant magnetoresistive thin film 6. Since the process of forming the film 5 is included, the electric path and magnetic path between the upper surface of the first soft magnetic film 3 and the giant magnetoresistive thin film 6 And the electric path and magnetic path between the upper surface of the second soft magnetic film 4 and the giant magnetoresistive thin film 6 are cut off, and the first soft magnetic film 3 to the second soft magnetic film 4 via the giant magnetoresistive thin film 6 It is possible to manufacture a thin film magnetoresistive element 1A in which the electric path and the magnetic path to be reached are restricted only in the arrangement direction of the first soft magnetic film 3 and the second soft magnetic film 4.

Next, a second embodiment of the thin film magnetoresistive element according to the present invention will be described based on FIG. 4 to FIG. 4 is a plan view of a thin film magnetoresistive element according to the second embodiment, FIG. 5 (a) is a cross sectional view taken along the line B-B in FIG. 4, and FIG. 6 is a cross sectional view of a thin film magnetoresistive element according to a comparative example. FIG. 8 is a table showing the specifications of the thin film magnetoresistive element according to the second embodiment and the thin film magnetoresistive element according to the comparative example, and FIG. 8 is a comparative example of the effects of the thin film magnetoresistive element according to the second embodiment. FIG. 6 is a graph showing comparison with FIG.

As shown in FIG. 4 and FIG. 5 (a), the thin film magnetoresistive element 1B of this example includes an insulating substrate 2 and a strip-shaped first soft magnetic film 3 formed on the insulating substrate 2. The nonmagnetic insulating film 5 formed on the upper surface of the first soft magnetic film 3 and the end surface of the nonmagnetic insulating film 5 and the first soft magnetic film 3 A giant magnetoresistive thin film 6 formed on a part of the upper surface of the insulating substrate 1 passing through one end face, and a giant magnetoresistance having one end in the longitudinal direction formed on one end face of the first soft magnetic film 3 And a belt-like second soft magnetic film 4 formed to be in contact with the thin film 6.

The film thickness tg of the giant magnetoresistive thin film 6 is equivalent to the gap length Lg of the thin film magnetoresistive element 1A according to the first embodiment, and a force that can be set to any size as needed. The gap length Lg force by making .0. 05 111 or more and less than 1. 05 μ

A thin film magnetoresistive element IB of less than 0 m can be realized. In the example of FIG. 5, the large magnetoresistive thin film 6 passes from a part of the top surface of the nonmagnetic insulating film 5 through one end face of the nonmagnetic insulating film 5 and the first soft magnetic film 3 to the top surface of the insulating substrate 2 It is sufficient if the force is formed at least on the end face of the first soft magnetic film 3.

The second soft magnetic film 4 is formed by sputtering a soft magnetic material of the same quality as the first soft magnetic film 3.

The other parts are the same as those of the thin film magnetoresistive element 1A according to the first embodiment, and therefore the corresponding parts are denoted by the same reference numerals and the description thereof will be omitted. In the thin film magnetoresistive element IB of this example, the nonmagnetic insulating film 5 is formed on the upper surface of the first soft magnetic film 3, and on the end face side of the first soft magnetic film 3 via the giant magnetoresistive thin film 6. Since the second soft magnetic film 4 is formed, the electric path and magnetic path leading to the second soft magnetic film 4 can be cut off via the giant magnetoresistive thin film 6 on the upper surface of the first soft magnetic film 3 It may only regulate the electrical path and the magnetic path leading to the ^second soft magnetic film 4 via the first soft magnetic film 3 from giant magnetoresistive thin film ⁶ on the first soft magnetic film 3 the arrangement direction of the ^second soft magnetic film 4 it can. Therefore, the dispersion of the magnetic flux and the nonuniformity of the magnetic flux path length can be suppressed, and the sensitivity of the magnetic field can be improved and the linearity thereof can be improved. When the giant magnetoresistive thin film is sufficiently thin as compared with the soft magnetic film, for example, 1 Z5 or less, as shown in FIG. 5 (b), the first soft magnetic film 3 and the second soft magnetic film 4 are Similar effects can be obtained even if the heights of the end faces do not match.

Further, as shown in FIG. 5, the thin-film magnetoresistive element 1 B of this example has a wide portion formed on one end of the wide portion 3 b formed on the first soft magnetic film 3 and the second soft magnetic film 4. A terminal portion for signal detection is provided at one end of the portion 6b, and a magnetic signal in a direction crossing the giant magnetoresistive thin film 6 in the thickness direction is detected. Therefore, since the thin film magnetoresistive element 1B of this example can regulate the gap length Lg between the first soft magnetic film 3 and the second soft magnetic film 4 with the film thickness tg of the giant magnetoresistive thin film 6, As in the case of forming a giant magnetoresistive thin film in the slit-like gap portion formed on the soft magnetic film, it is possible to improve the magnetic field sensitivity due to the reduction of the gap length in which the manufacturing length is not limited.

That is, as shown in FIG. 6, after a slit-like gap portion 203 is formed at the central portion of the soft magnetic film 202 formed on the substrate 201 by applying a microfabrication technique such as ion beam etching. The thin-film magnetoresistive element 200 (the thin-film magnetoresistive element according to the comparative example) in which the giant magnetoresistive thin film 204 is formed by sputtering in the gap portion 203 also has the inside of the gap portion 202 even when the sputtering conditions are optimized. It is difficult to reduce the gap length to less than 0.5 m because the formation of a homogeneous giant magnetoresistive thin film 203 becomes difficult. On the other hand, the thin film magnetoresistive element 1 B of this example regulates the gap length Lg between the first soft magnetic film 3 and the second soft magnetic film 4 with the film thickness tg of the giant magnetoresistive thin film 6. Thus, by controlling the film thickness tg of the giant magnetoresistance thin film 6, a thin film magnetoresistance element having a gap length of 0.5 m or less can be manufactured. Therefore, as shown in FIG. 7, the inventors of the present invention have compared the thin-film magnetoresistive element according to the comparative example in which the film thickness tg of the giant magnetoresistive thin film 203 is 0.25 m and the gap length Lg is 0.5 m. A thin-film magnetoresistive element 1B according to the second embodiment having a thickness tg of 0.25 m and a gap length Lg of 0.1 m for the giant magnetoresistive thin film 5 is fabricated, and the respective magnetic field sensitivities are Compared. As is clear from Figure 7, the other specifications are the same.

When the strength of the magnetic field at the center of the gap was measured while variously changing the magnitude of the external magnetic field Hex, as shown in FIG. 8, the external magnetic field Hex of the thin film magnetoresistive element 1 B according to the second embodiment example. The rate of change of the strength of the magnetic field at the center of the gap with respect to the change in the gap is nearly twice that of the thin film magnetoresistive device 200 according to the comparative example, and the magnetic field sensitivity of the thin film It has been demonstrated that

Further, in the thin film magnetoresistive element 1 B of this example, since the gap length Lg is regulated by the film thickness tg of the giant magnetoresistive thin film 6 as described above, the microfabrication technique is applied as a means for forming the gap portion. The manufacturing process of the thin film magnetoresistive element which does not require it can be simplified, and the thin film magnetoresistive element can be manufactured at low cost.

Hereinafter, a method of manufacturing the thin film magnetoresistive element IB according to FIG. 5 (a) in the second embodiment will be described based on FIG. FIG. 9 is a flow chart showing a manufacturing procedure of the thin film magnetoresistive element 1B.

First, a soft magnetic film to be the origin of the first soft magnetic film 3 is formed on one surface of the insulating substrate 2 to a uniform thickness by sputtering or the like (step Sll). Next, a photoresist layer is uniformly formed on the soft magnetic film, and through a light exposure step and a development step, a mask for forming a first soft magnetic film is formed (step S12). Next, the portion covered with the photoresist layer of the soft magnetic film is removed by etching or ion milling, and then the remaining photoresist layer is removed (step S13). As a result, the required first soft magnetic film 3 is formed on one side of the insulating substrate 2. Next, the nonmagnetic insulating film 5 is formed by sputtering (step S14), and a photoresist layer is uniformly formed again over the entire top surface of the insulating substrate 2 including the top surface of the first soft magnetic film 3 Then, a mask for nonmagnetic insulating film formation is formed (step S15). Next, the oxide film of the portion not covered with the photoresist layer is removed by etching or ion milling, and thereafter, the remaining photoresist layer is removed (Procedure S 16). Thus, the nonmagnetic insulating film 5 is stacked on the top surface of the first soft magnetic film 3. Next, a giant magnetoresistive thin film 6 is deposited by sputtering (procedure S17), and then a photoresist layer is uniformly formed on the giant magnetoresistive thin film 6, and then through an exposure step and a developing step, a giant magnetoresistive resistor is formed. Form a mask for thin film 6 (step S18). Next, the portion not covered with the photoresist layer is removed by etching or ion milling, and thereafter, the remaining photoresist layer is removed (procedure S19). Thus, the giant magnetoresistive thin film 6 is formed on the end face of the first soft magnetic film 3 and the end face of the nonmagnetic insulating film 5. Next, the nonmagnetic insulating film 7 is formed by sputtering on the insulating substrate 2 (step S20), and the oxide film of the portion not covered with the photoresist layer is removed by etching or ion milling, and then remaining. Remove the photoresist layer (Step S21). As a result, the nonmagnetic insulating film 7 is stacked on the insulating substrate 2 in a portion in contact with the end face of the giant magnetoresistive thin film 6. Next, a soft magnetic film to be the origin of the second soft magnetic film 3 is formed on the nonmagnetic insulating film 7 by plating or sputtering to a uniform thickness (step S22), and a photoresist layer is formed on the soft magnetic film. Are uniformly formed, and through a light exposure step and a development step, a mask for forming a second soft magnetic film is formed (step S23). Next, the portion covered with the photoresist layer of the soft magnetic film is removed by etching, ion milling or the like, and thereafter, the remaining photoresist layer is removed (procedure S24). Thus, the thin film magnetoresistive element 1B according to the second embodiment shown in FIGS. 4 and 5 is obtained.

According to the manufacturing method of this example, since the step of forming nonmagnetic insulating film 5 between the upper surface of first soft magnetic film 3 and giant magnetoresistive thin film 6 is included, the upper surface of first soft magnetic film 3 is formed. Also, the electric path and magnetic path leading to the second soft magnetic film 4 are interrupted through the giant magnetoresistive thin film 6, and the electric path extending from the first soft magnetic film 3 to the second soft magnetic film 4 through the giant magnetoresistive thin film 6 A thin film magnetoresistive element 1 B in which the magnetic path is restricted only in the direction of arrangement of the first soft magnetic film 3 and the second soft magnetic film 4 can be manufactured.

Next, a third embodiment of the thin film magnetoresistive element according to the present invention will be described based on FIG. 10 to FIG. FIG. 10 is a plan view of a thin film magnetoresistive element according to a third embodiment, and FIG. 11 is a cross-sectional view taken along the line CC in FIG.

As shown in FIG. 10 and FIG. 11, the thin film magnetoresistive element 1 C of this example includes an insulating substrate 2, a strip-shaped first soft magnetic film 3 formed on the insulating substrate 2, and a first soft magnetic film. Upper surface of magnetic film 3 near one end And the nonmagnetic insulating film 5 formed on the outer peripheral portion and the end face of the upper surface and the end face of the first soft magnetic film 3 and the upper face and the lower surface of the one end portion Is formed of a band-like second soft magnetic film 4 formed to be in contact with the giant magnetoresistive thin film 6 exposed from the nonmagnetic insulating film 5.

The configuration of each part is the same as that of the thin film magnetoresistive element 1 B according to the second embodiment except for the laminated structure of each of the films 3 to 6, so the corresponding parts are denoted by the same reference numerals. I will omit the explanation.

In the thin film magnetoresistive element 1 C of this example, the giant magnetoresistive thin film 6 is formed on the upper surface of the first soft magnetic film 3, and the end face of the first soft magnetic film 3 and the end face of the second soft magnetic film 4 Since the nonmagnetic insulating film 5 is interposed between them, the electric path and the magnetic path leading to the end face of the first soft magnetic film 3 and the end face of the second soft magnetic film 4 can be cut off. The electric path and magnetic path from the film 3 to the second soft magnetic film 4 via the giant magnetoresistive thin film 6 can be regulated only in the film thickness direction of the giant magnetoresistive thin film 6. Therefore, it is possible to suppress the dispersion of the magnetic flux and the nonuniformity of the magnetic flux path length, and it is possible to improve the sensitivity of the magnetic field and the linearity thereof. Further, since the giant magnetoresistive thin film 6 is formed on the upper surface of the first soft magnetic film 3 in the thin film magnetoresistive element 1 C of this example, the giant magnetoresistive thin film 6 is formed on the end face of the first soft magnetic film 3. In comparison, the control of the film thickness of the giant magnetic resistance thin film 6 becomes easy, and from this point as well, the magnetic field sensitivity can be improved. Furthermore, the thin film magnetoresistive element 1C of this example can regulate the gap length Lg between the first soft magnetic film 3 and the second soft magnetic film 4 with the film thickness tg of the giant magnetoresistive thin film 6 Therefore, as in the case of forming a giant magnetoresistive thin film in the slit-like gap portion formed in the soft magnetic film, the magnetic field sensitivity can be improved by reducing the gap length without any limitation on the gap length. Can.

Hereinafter, a method of manufacturing the thin film magnetoresistive element 1C according to the third embodiment will be described based on FIG. FIG. 12 is a flow chart showing a manufacturing procedure of the thin film magnetoresistive element 1C.

First, the insulating substrate 2 on which one side of the soft magnetic film to be the origin of the first soft magnetic film 3 is formed to a uniform thickness by plating or the like is prepared (step S 21). Next, a photoresist layer is uniformly formed on the soft magnetic film, and a mask for forming a first soft magnetic film is formed through an exposure step and a development step (step S22). Next, the portion not covered with the photoresist layer of the soft magnetic film The portion is removed by etching, ion milling or the like, and then the remaining photoresist layer is removed (step S23). Thereby, the required first soft magnetic film 3 is formed on one side of the insulating substrate 2. Next, a giant magnetoresistive thin film 6 is deposited by sputtering (procedure S24), and then a photoresist layer is uniformly formed on the giant magnetoresistive thin film 6, and then through an exposure step and a development step, a giant magnetoresistance is produced. Form a mask of the thin film 6 (step S25). Next, the portion covered with the photoresist layer is removed by etching or ion milling, and thereafter, the remaining photoresist layer is removed (procedure S26). Thereby, the giant magnetoresistive thin film 6 is stacked on the top surface of the first soft magnetic film 3. Then, a photoresist layer is uniformly formed on the entire upper surface of the insulating substrate 2 including the upper surface of the first soft magnetic film 3 and the upper surface of the giant magnetoresistive thin film 6, and through the exposure step and the developing step, the giant magnetoresistive thin film The outer peripheral portion of the upper surface of the sixth part Force is the end of the giant magnetoresistive thin film 6 and the partial array of the upper surface of the first soft magnetic film 3 The opening is only in the part facing the end surface of the first soft magnetic film 3 The formed nonmagnetic insulating film forming mask is formed (step S 27). Next, the nonmagnetic insulating film 5 is formed by sputtering in the opening of the photoresist layer (step S28), and after force is applied, the remaining photoresist layer is removed (step S29). As a result, the nonmagnetic insulating film 5 is formed on the required portions of the first soft magnetic film 3 and the giant magnetoresistive thin film 6 and the insulating substrate 2. Next, the second soft magnetic film 4 is formed by sputtering (step S30), and after applying force, the soft magnetic film is removed by ion milling, etching or the like, and the remaining photoresist layer is removed (step S31). Next, a photoresist layer is uniformly formed, and a mask for a second soft magnetic film is formed through an exposure step and a development step (step S32). Thereby, a thin film magnetoresistive element 1C according to the third embodiment shown in FIGS. 10 and 11 is obtained.

According to the manufacturing method of the present example, the nonmagnetic state between the upper surface of the giant magnetoresistive thin film 6 and the lower surface of the second soft magnetic film 4 and between the end surface of the first soft magnetic film 3 and the end surface of the second soft magnetic film 4 Since the step of forming the insulating film 5 is included, the electric path and magnetic path leading to the second soft magnetic film 4 via the giant magnetoresistive thin film 6 on the upper surface of the first soft magnetic film 3 and the first soft magnetic film 3 The electric path and magnetic path leading to the second soft magnetic film 4 are cut off directly, and the electric path and magnetic path from the first soft magnetic film 3 to the second soft magnetic film 4 via the giant magnetoresistive thin film 6 are huge. A thin film magnetoresistive element 1 C regulated only in the film thickness direction of the magnetoresistive thin film 6 can be manufactured. FIG. 13 shows a thin film magnetoresistive element ID according to a fourth embodiment of the present invention. FIG. 13 is a cross-sectional view of main parts of a thin-film magnetoresistive element 1D according to the fourth embodiment.

As shown in FIG. 13, in the thin film magnetoresistive element 1 D of this example, the first and second soft magnetic films 3 and 4 are formed on the insulating substrate 2 with the required gap g therebetween, The nonmagnetic insulating film 5 is laminated on the upper surfaces of the first and second soft magnetic films 3 and 4 respectively, and the end faces of the first and second soft magnetic films 3 and 4 and the end faces of the nonmagnetic insulating film 5 are giant magnetic films. A third soft magnetic film 11 is formed via the resistance thin film 6.

The same configuration as that of the thin film magnetoresistive element 1A according to the first embodiment can also be achieved by the above-described configuration. In addition, if a hard magnetic film is formed instead of the third soft magnetic film 11, a noise effect can be expected.

FIG. 14 shows a thin film magnetoresistive element 1E according to a fifth embodiment of the present invention. FIG. 14 is a plan view of the main part of a thin film magnetoresistive element 1E according to the fifth embodiment.

As shown in FIG. 14, in the thin film magnetoresistive element 1E of this example, the second soft magnetic film 5 is formed in a cross shape, and the giant magnetic films are giant magnetism in the direction orthogonal to each other with the second soft magnetic film 5 as a center. A resistive thin film 6 (not shown), a nonmagnetic insulating film 5 and a first soft magnetic film 3 (not shown) are formed. The laminated structure of the first soft magnetic film 3, the nonmagnetic insulating film 5, the giant magnetoresistive thin film 6, and the second soft magnetic film 4 is the thin film magnetoresistive element 1A according to the first to third embodiments. Same as either IB or 1C.

The thin film magnetoresistive element 1E of this example can simultaneously detect magnetic fields in two orthogonal directions, so it can be used not only as a general magnetic sensor but also as a magnetic sensor for special purposes such as a compass. It can be used.

Hereinafter, an embodiment of the magnetic sensor according to the present invention will be described based on FIG. 15 to FIG. FIG. 15 is a plan view of the magnetic sensor according to the embodiment, FIG. 16 is a cross-sectional view of the main part of the fixed resistance element applied to the magnetic sensor according to the embodiment, and FIG. 17 is equivalent to the magnetic sensor according to the embodiment. It is a circuit diagram.

As shown in FIG. 15, the magnetic sensor 21 of the present example is provided with the thin film magnetic resistance element 1A according to the first embodiment example on the two opposing sides and the fixed resistance on the other opposing two sides. A bridge circuit including an element 22 is formed on the end of each of the soft magnetic films 3 and 4 constituting the thin film magnetoresistive element 1A. A terminal 23 is formed.

The fixed resistance element 22 is, as shown in FIG. 16, an insulating substrate 24, a strip-shaped first nonmagnetic metal film 25 formed on the insulating substrate 24, and one end of the first nonmagnetic metal film 25. The nonmagnetic insulating film 26 formed on the upper surface of the substrate 24 and part of the upper surface of the nonmagnetic insulating film 26 pass through one end surface of the first nonmagnetic metal film 25 and the nonmagnetic insulating film 26 to form the substrate 24. A giant magnetoresistive thin film 27 formed on a part of the upper surface, and a strip formed so that one end in the lengthwise direction covers the giant magnetoresistive thin film 27 and does not contact the first nonmagnetic metal film 25 And a second nonmagnetic metal film 28.

The magnetic sensor 21 of this example uses the thin film magnetoresistance element 1A according to the first embodiment as the thin film magnetoresistance element, so the magnetic field sensitivity is high and the linearity is excellent. Further, the magnetic sensor 21 of the present example is configured by forming a bridge circuit by two thin film magnetoresistive elements 1A provided on two opposing sides and fixed resistance elements 22 provided on the other two opposing sides. Therefore, it is possible to perform high-precision magnetic field detection by the null method which does not depend on the fluctuation of the power supply voltage and the input impedance and nonlinearity of the detector.

That is, as shown in FIG. 17, the resistance values of the two thin film magnetoresistive elements 1 A are R and R respectively.

Assuming that the resistances of the two fixed resistance elements 22 are R and R respectively, the input voltage Vin

twenty four

The output voltage Vout for is expressed by the following equation.

[Number 1]

V. _ut = VV

As is clear from this equation, the output voltage Vout of the bridge circuit is determined only by the resistance values R, R, R, R of each element and the input voltage Vin, and in the equilibrium state, the output voltage

2 3 4

Since the voltage Vout becomes zero, a highly accurate magnetic field detection independent of the fluctuation of the power supply voltage and the input impedance or nonlinearity of the detector becomes possible, and a highly practical magnetic sensor can be realized.

Although the thin film magnetoresistive element 1A according to the first embodiment is used as the thin film magnetoresistive element in the above embodiment, a thin film magnetic resistance according to the second embodiment may be used instead. The element IB or the thin film magnetoresistive element 1C according to the third embodiment can also be used. Further, in the embodiment described above, one having the first nonmagnetic metal film 25, the nonmagnetic insulating film 26, the giant magnetoresistive thin film 27 and the second nonmagnetic metal film 28 is used as the fixed resistance element 21. Other fixed resistance elements can also be used.

Brief description of the drawings

[FIG. 1] A plan view of a thin film magnetoresistive element according to a first embodiment.

FIG. 2 is a cross-sectional view taken along the line A-A in FIG.

FIG. 3 is a flow chart showing a method of manufacturing a thin film magnetoresistive element according to the first embodiment.

FIG. 4 is a plan view of a thin film magnetoresistive element according to a second embodiment example.

FIG. 5 is a cross-sectional view of a thin film magnetoresistive element according to a second embodiment example.

FIG. 6 is a cross-sectional view of a thin film magnetoresistive element according to a comparative example.

FIG. 7 is a table showing the specifications of a thin film magnetoresistive element according to a second embodiment and a thin film magnetoresistive element according to a comparative example.

FIG. 8 is a graph showing the effect of the thin film magnetoresistive element according to the second embodiment in comparison with a comparative example.

FIG. 9 is a flow chart showing a method of manufacturing a thin film magnetoresistive element according to a second embodiment example.

FIG. 10 is a plan view of a thin film magnetoresistive element according to a third embodiment.

[FIG. 11] It is CC sectional drawing of FIG.

FIG. 12 is a flow chart showing a method of manufacturing a thin film magnetoresistive element according to a third embodiment.

FIG. 13 is a cross-sectional view of main parts of a thin-film magnetoresistive element according to a fourth embodiment;

FIG. 14 is a cross-sectional view of main parts of a thin-film magnetoresistive element according to a fifth embodiment;

FIG. 15 is a plan view of a magnetic sensor according to an embodiment.

FIG. 16 is a cross-sectional view of main parts of a fixed resistance element applied to a magnetic sensor according to an embodiment example.

FIG. 17 is an equivalent circuit diagram of a magnetic sensor according to an embodiment example.

FIG. 18 is a cross-sectional view of main parts of a thin-film magnetoresistive element according to a conventional example.

Explanation of sign

[0080] 1A-: LE thin film magnetoresistive element Insulating substrate First soft magnetic film First soft magnetic film Nonmagnetic insulating film Giant magnetoresistive thin film Third soft magnetic film Magnetic sensor Fixed resistance element terminal

Claims

The scope of the claims

[1] A giant magnetoresistive thin film, first and second soft magnetic films electrically and magnetically connected at one end via the giant magnetoresistive thin film, the first soft magnetic film, and the second soft magnetic film A nonmagnetic insulating film interposed between at least one of the magnetic films and the giant magnetoresistive thin film, the nonmagnetic insulating film being in contact with the soft magnetic film facing the giant magnetoresistive thin film The electric path and the magnetic path from the first soft magnetic film to the second soft magnetic film are regulated in one direction through the giant magnetoresistive thin film at a position where the area is narrowed, A thin film magnetoresistive element characterized in that the soft magnetic film of No. 2 has a terminal portion for signal detection.

[2] The end faces of the first and second soft magnetic films are disposed opposite to each other via a required gap, and a nonmagnetic insulating film is formed on the upper surfaces of the first and second soft magnetic films, respectively. Forming the giant magnetoresistive thin film in the gap and the periphery thereof, and connecting the first soft magnetic film to the second soft magnetic film through the giant magnetoresistive thin film by the nonmagnetic insulating film The thin film magnetoresistive element according to claim 1, wherein the magnetic path is restricted only in the arrangement direction of the first soft magnetic film and the second soft magnetic film.

[3] The nonmagnetic insulating film is stacked on the giant magnetoresistive thin film with its end faces aligned, and the first soft magnetic film is formed to cover one of the end faces and a part of the nonmagnetic insulating film, A second soft magnetic film is formed covering the other end face and a part of the nonmagnetic insulating film, and the nonmagnetic insulating film allows the first soft magnetic film to be formed from the first soft magnetic film through the giant magnetoresistive thin film. 2. The thin film magnetoresistive element according to claim 1, wherein the electric path and the magnetic path leading to the soft magnetic film are restricted only in the direction of the lamination surface of the giant magnetoresistive thin film.

[4] The nonmagnetic insulating film is formed on the upper surface of the first soft magnetic film, and the giant magnetoresistive thin film is formed on the upper surface and the end surface of the nonmagnetic insulating film and the end surface of the first soft magnetic film. Forming the second soft magnetic film such that one end thereof is in contact with the giant magnetoresistive thin film formed on the end face of the nonmagnetic insulating film and the end face of the first soft magnetic film, and the nonmagnetic insulating film The electric path and magnetic path from the first soft magnetic film to the second soft magnetic film through the giant magnetoresistive thin film are restricted only in the direction in which the first soft magnetic film and the second soft magnetic film are arranged. The thin film magnetoresistive element according to claim 1, characterized in that

[5] The thin film magnetism according to claim 4, wherein the second soft magnetic film is laminated on the nonmagnetic insulating film formed such that one end thereof is in contact with the giant magnetoresistive thin film. Resistance element.

[6] The giant magnetoresistive thin film is formed on a portion of the top surface of the first soft magnetic film, and the non-upper surface and the end surface of the first soft magnetic film and the outer peripheral portion and the edge of the top surface of the giant magnetoresistive thin film A magnetic insulating film is formed, and the second soft magnetic film is formed such that the lower surface of one end portion is in contact with the giant magnetoresistive thin film exposed from the nonmagnetic insulating film, and the nonmagnetic insulating film forms the giant The electric path and magnetic path from the first soft magnetic film to the second soft magnetic film through the magnetoresistive thin film are restricted only in the film thickness direction of the giant magnetoresistive thin film. Thin film magnetoresistive element.

7. The giant magnetoresistive thin film according to any one of claims 1 to 4, wherein the giant magnetoresistive thin film is formed of a magnetic nonmagnetic film formed by dispersing ferromagnetic fine particles in an insulator matrix. The thin film magnetoresistive element according to item 1.

[8] A thin film characterized in that the film thickness of the giant magnetoresistive thin film formed between the first soft magnetic film and the second soft magnetic film is not less than 0. 05 m and not more than 1.0 m. Magnetoresistance element.

[9] A step of forming a first soft magnetic film and a second soft magnetic film opposite to each other through a required gap on an insulating substrate,

Forming a nonmagnetic insulating film on the upper surface of the first soft magnetic film and the upper surface of the second soft magnetic film;

Forming a giant magnetoresistive thin film in the gap and on the upper surface and the end surface of the nonmagnetic insulating film.

[10] forming a first soft magnetic film on an insulating substrate;

Forming a nonmagnetic insulating film on the top surface of the first soft magnetic film;

Forming a giant magnetoresistive thin film on the insulating substrate following the one end surface of the first soft magnetic film, the one end surface and the upper surface of the nonmagnetic insulating film following it, and the one end surface of the first soft magnetic film; ,

A second soft magnetic film, one end of which is in contact with the end surface of the nonmagnetic insulating film, the end surface of the first soft magnetic film, and the giant magnetoresistive thin film formed on the insulating substrate, on the insulating substrate. And (e) forming a film.

[11] forming a first soft magnetic film on an insulating substrate;

Forming a giant magnetoresistive thin film near one end of the top surface of the first soft magnetic film; a top surface of the first soft magnetic film and a part of an end surface and a top surface of the giant magnetoresistive thin film following the first soft magnetic film; (1) forming a nonmagnetic insulating film on one end face of the soft magnetic film, and forming a second soft magnetic film on the insulating substrate in contact with the giant magnetoresistive thin film whose one end is exposed from the nonmagnetic insulating film. And a process for producing the thin film magnetoresistive element.

[12] A giant magnetoresistive thin film, first and second soft magnetic films electrically and magnetically connected at one end via the giant magnetoresistive thin film, a surface of at least the first soft magnetic film, and It is formed on one side of the surface of the second soft magnetic film and restricts the electric path and magnetic path from the first soft magnetic film to the second soft magnetic film through the giant magnetoresistive thin film in one direction. Two thin film magnetoresistive elements having a magnetic insulating film and having terminal portions for signal detection on the first and second soft magnetic films are provided on two opposing sides and fixed on the other opposing two sides What is claimed is: 1. A magnetic sensor using a thin film magnetoresistive element, characterized in that it comprises a bridge circuit with a resistive element.