JPH01251412A - Magneto-resistance effect type magnetic head - Google Patents

Abstract

PURPOSE:To narrow a gap by reducing film thickness between a magnetosensitive part and an upper magnetic material and between the part and a lower magnetic material and to improve a frequency characteristic and productivity by arranging a forward electrode layer and a backward electrode layer at sides opposite to a conductor for generating a bias magnetic field via the magnetosensitive part. CONSTITUTION:The title magnetic head is formed in shield type structure in which the magnetosensitive part 8, the forward electrode layer 9, the rearward electrode layer 10, and the conductor 11 for generating the bias magnetic field are sandwiched by the upper magnetic material 13 and the lower magnetic material 14 via insulating layers (12a-12d). In the magnetosensitive part 8, at least one side of a pair of soft magnetic thin films 8a and 8b having a magneto-resistance effect is laminated via an intermediate non-magnetic layer 8c, and the forward electrode 9 and the rearward electrode 10 are connected adhesively on the forward end part and the rearward end part of the magnetosensitive part 8, respectively. Since the forward electrode layer 9 and the rearward electrode layer 10 are formed at the sides opposite to the conductor 11 for generating the bias magnetic field via the magnetosensitive part 8, it is possible to reduce the film thickness between the magnetosensitive part 8 and the upper magnetic material 13 and between the part 8 and the lower magnetic material 14, therefore, to reduce magnetic gap length.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a magnetoresistive magnetic head (so-called MR magnetic head) for reproducing magnetic recording signals recorded on a magnetic recording medium, and in particular to The present invention relates to an MR magnetic head having a structure compatible with increased density.

[Requirement of the invention]

The present invention provides a magnetoresistive magnetic head for reproducing magnetic recording signals recorded on a magnetic recording medium, in which a front electrode layer and a rear electrode layer for applying a sense current to a magnetically sensitive part are connected via the magnetically sensitive part. By locating it on the opposite side of the bias magnetic field generating conductor that applies a bias magnetic field to the magnetic sensitive part, the magnetic gap length is shortened, thereby improving the frequency characteristics.

(Prior Art) In general, devices that read magnetic recording signals recorded on magnetic recording media only have a playback function, for example.
Magnetoresistive magnetic head (hereinafter referred to as M
This is called an R-type magnetic head. )It has been known.

The MR type magnetic head is a reproduction head that utilizes the magnetoresistive effect phenomenon in which the electrical resistance value changes depending on the angle formed between the direction of magnetization found in the transition metal and the direction of the current flowing inside the head.

That is, when the MR magnetic thin film receives leakage magnetic flux from the magnetic recording medium, the direction of the MRI thin film is rotated by the magnetic flux, and the direction of the current flowing inside the MR magnetic thin film is at an angle corresponding to the amount of magnetic flux. Motsu. Therefore, the electrical resistance value of the MR magnetic thin film changes, and a voltage change corresponding to the amount of change appears at the electrodes at both ends of the MR magnetic thin film through which current is flowing, so that the magnetic recording signal can be read out as a voltage signal.

Generally, a single-layer thin film is used as the MR magnetic thin film, and this constitutes a magnetically sensitive part. However, this single layer MR
In an MR type magnetic head made of a 1FF thin film, Barkhausen noise, that is, the generation of noise due to movement of domain walls becomes a problem. In other words, this MR magnetic thin film has a magnetic domain configuration in order to maintain a state in which the sum of magnetostatic energy caused by magnetic anisotropy energy, shape anisotropy, etc. is minimized as a whole layer. When an external magnetic field is applied to the layer, the domain walls move and Barkhausen noise is generated.

Therefore, in order to avoid the above-mentioned Barkhausen noise, the applicant of the present application has proposed using a non-magnetic intermediate layer as previously disclosed in Japanese Patent Application No. 17913/1982 and Japanese Patent Application No. 011932/1982. We have proposed an MR type magnetic head using a laminated type magnetically sensitive section in which a pair of soft magnetic thin films are laminated.

The MR type magnetic head has a configuration as shown in FIG. 14, for example.

That is, as shown in FIG. 14, the MR type magnetic head has an electrode layer (2) on the -main surface of the magnetically sensitive part (1) for applying a sense current to the magnetically sensitive part (1), (3) is formed, and the above-mentioned magnetically sensitive part (
A bias magnetic field generating conductor (5) for applying a bias magnetic field to 1) is laminated, and these are layered with an insulating layer (4a),
(4c) through the lower magnetic body (6) and the upper magnetic body (7).
), it has a so-called shield type structure. The magnetically sensitive portion (1) includes a pair of soft magnetic thin films (la), (lb), at least one of which has a magnetoresistive effect.
) are laminated with a nonmagnetic intermediate layer (1c) interposed therebetween.

In this way, by forming the magnetically sensitive part (1) into a laminated structure, the axes of easy magnetization of the pair of soft magnetic thin films (la) and (lb) are in the same direction, and the directions of magnetization are opposite to each other. Therefore, the magnetically sensitive portion (1) does not have a plurality of magnetic domains in the same plane. Therefore, a magnetic head that generates less Barkhausen noise can be realized.

[Problem to be solved by the invention]

By the way, in the above MR type magnetic head, the electrode layer (2)
, (3) and the bias magnetic field generating conductor (5) are both laminated on the -main surface of the magnetically sensitive portion (1). Therefore, between the electrode layers (2), (3) and the bias magnetic field generating conductor (5), the bias magnetic field generating conductor (5)
Since insulating layers (4b) and (4c) are required for insulation between the upper magnetic body (7) and the upper magnetic body (7), the shield gear between the magnetically sensitive part (1) and the upper magnetic body (7) is required. The length is restricted by these insulating layers (4b) and (4c). In fact, when the above-described structure is adopted, the shield gap length is limited to about 0.8βm.

On the other hand, the insulating layer (4a) between the magnetically sensitive part (1) and the lower magnetic body (6) is originally
) Since there is nothing to be laminated between the insulating film (4)
The film thickness in a) may be at least as thick as can provide insulation. However, the magnetic sensing part (1) and the lower magnetic body (6
) is not the same as the shield gap length L1 between the magnetically sensitive part (1) and the upper magnetic body (7), the output waveform will be asymmetrical.
The film thickness of 4a) is made equal to the previous shield gap length.

Therefore, since the insulating layer (4a) has an extra thickness, the magnetic gap length of the magnetic head is 1.6 μm.
becomes. This value does not include the film thickness of the magnetically sensitive part (1).

As described above, in an MR type magnetic head with a large magnetic gap length, the recording density is such that the reproduction output value becomes 1/2.

The value is 22 to 23 KPCI, and this. In order to further improve the value and cope with increased recording density, it is necessary to shorten the magnetic gap length. However, in the above-described structure, both the conductor thin film and the insulating film are thin to the limit, so it is impossible to further narrow the gap unless the structure is changed.

Therefore, the present invention was proposed to solve the above problems, and provides a magnetoresistive magnetic head that can shorten the magnetic gap length, improve frequency characteristics, and improve productivity. The purpose is to

[Means to solve the problem]

In order to achieve the above object, the present invention provides a magnetically sensitive part in which a pair of soft magnetic thin films, at least one of which has a magnetoresistive effect, is laminated on 71H with a non-magnetic intermediate layer interposed therebetween, and a magnetically sensitive part of the magnetically sensitive part. A front electrode layer and a rear electrode layer are respectively deposited on the front end portion and the rear end portion, and a bias magnetic field generating conductor is provided that extends across the magnetically sensitive portion via an insulating layer. The electrode layer and the rear electrode layer are arranged on the opposite side of the bias magnetic field generating conductor with the magnetic sensing part interposed therebetween.

[Effect]

In the magnetoresistive magnetic head of the present invention, the magnetically sensitive portion is laminated with a non-magnetic intermediate layer interposed between a pair of soft magnetic thin films having a magnetoresistive effect. They become magnetostatically coupled, and the coupling due to interaction according to Coulomb's law becomes sufficiently strong. Therefore, if the directions of the easy magnetization axes of the opposing soft magnetic thin films are set in the same direction, the directions of magnetization will be opposite to each other, so that the magnetically sensitive part will not have a plurality of magnetic domains in the same plane. Therefore, the occurrence of Barkhausen noise is effectively prevented.

Since the front electrode layer and the rear electrode layer are disposed on the opposite side of the bias magnetic field generating conductor via the magnetic sensing part, the bias magnetic field generating conductor is disposed between the magnetic sensing part and the upper magnetic body. The thickness of the electrode layer and the conductor for generating a bias magnetic field are thinner than in a structure in which both the electrode layer and the conductor for generating a bias magnetic field are laminated on the same surface of the magnetically sensitive part.

On the other hand, since only the electrode layer is laminated between the magnetically sensitive portion and the lower magnetic body, the film thickness therebetween is also thin.

Therefore, the magnetic gap length of the magnetic head becomes shorter,
Further improvement in frequency characteristics can be achieved.

〔Example〕

Hereinafter, one embodiment of a magnetoresistive magnetic head to which the present invention is applied will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the MR magnetic head of this embodiment includes a magnetically sensitive portion (8), a front electrode layer (9), a rear electrode layer (10), and a bias magnetic field generating conductor (11). ) insulated R
(12a), (12b), (12c), (
The upper magnetic body (13) and the lower magnetic body (1
4) and has a so-called shield type structure.

A magnetically sensitive part (8), a front electrode layer (9), and a rear electrode layer (10) are formed between the upper magnetic body (13) and the lower magnetic body (14).

The bias magnetic field generating conductor (11) is connected to the lower magnetic body (
14) Front electrode layer (9) via insulating layer (12d) on top
and posterior electrode! (10) are respectively formed, a magnetically sensitive part (8) is formed thereon, and an insulating layer (12) is further formed thereon.
It has a laminated structure in which bias magnetic field generating conductors (11) are laminated via b).

Here, the magnetically sensitive portion (8) includes a pair of soft magnetic thin films (8a) and (8b), at least one of which has a magnetoresistive effect.
are laminated with a nonmagnetic intermediate layer (8c) interposed therebetween. And both the soft magnetic thin films (8a) and (8b
), the amount of magnetic flux of both soft magnetic thin films (8a), (8b) is matched by selecting the saturation magnetic flux density, thickness, etc.
Regarding b), it is generally closed.

As a result, the magnetically sensitive part (8) enters a magnetostatically coupled state due to the interposition of the nonmagnetic intermediate layer (8c), and the opposing soft magnetic thin W
The directions of the easy magnetization axes of X (8a) and (8b) are in the same direction, and the directions of their magnetizations are opposite to each other, so the magnetically sensitive part (8) does not have a plurality of magnetic domains in the same plane. Therefore, generation of Barkhausen noise due to movement of domain walls is effectively prevented.

The soft magnetic thin films (8a) and (8b) may be made of, for example, Ni, Fe, Co, etc., or two of these.
three or more alloys, such as Ni-Fe, Ni-Co.

Examples include Ni-Fe-Co.

Further, the material of the non-magnetic intermediate layer (8c) may include, for example, Al.
□0. Insulators such as or 5ift or Mo.

Non-magnetic metals such as Ti and Ag are used.

The film thickness of the non-magnetic intermediate layer (8c) is such that magnetostatic interaction acts more dominantly than exchange interaction between the bimagnetic thin films (8a) and (8b). For example, from 5 to 10,000 people, it is particularly preferable to set the film thickness in the range of 5 to 500 people so that the effect can be better exhibited.

In addition, when the magnetically sensitive part (8) is composed of soft magnetic thin films (8a) and (8b), both of which have a magnetoresistive effect, the bimagnetic thin films (8a) and (8b) are made of the same material and the same material. It is desirable to make the dimensions. On the other hand, when only one side of the magnetically sensitive part (8) is composed of a soft magnetic thin film (8a) having a magnetoresistive effect, the other soft magnetic thin film (8a) has a magnetoresistive effect.
For b), the material, thickness, etc. are selected so that it has a sufficiently larger electrical resistance than the soft magnetic thin film (8a) having a magnetoresistive effect. At that time, also in this case, a double magnetic thin film (
It is necessary to satisfy the condition that the magnetic flux amounts of 8a) and (8b) match.

The soft magnetic thin film (8b) on the lower magnetic body (14) side of the magnetically sensitive part (8) having the stacked stone structure has a front electrode that applies a sense current to the magnetically sensitive part (8). Layer (9) and backward electric iJ! (10) is formed by adhesion.

The front electrode layer (9) is located at the front end of the magnetically sensitive part (8), and the rear electrode layer (10) is located at the rear end of the magnetically sensitive part (8).
) extends substantially perpendicular to the direction of extension. Furthermore, these front electrode layer (9), rear electrode J!
(10) are located away from the upper magnetic body (13) and extend from both ends of the front electrode 71 (9) and the rear electrode N (10) in the direction of extension of the magnetic sensing part (8), leading out the terminals. Part (9
a).

(10a) are formed respectively. Parts of both terminal lead-out portions (9a) and (10a) serve as terminals L+ and Lz through which a sense current flows.

Therefore, if a sense current i is caused to flow between these terminals j, , t, the sense current i flows in the order of the front electrode layer (9), the magnetic sensing part (8), and the rear electrode layer (lO). Note that the direction of the sense 'gi current i is preferably the same as the signal magnetic field from the magnetic recording medium in order to prevent Barkhausen noise from occurring. In addition, the front electrode layer (9
) and the rear electrode layer (10), normal metal conductors can be used, but in this example, a laminated metal conductor in which Ti/Cu/Ti was laminated in this order was used.

Further, an insulating layer (12a) is formed between the front electrode layer (9) and the rear electrode layer (10). This insulating layer (1
2a) is the front electrode N (9) and the rear electrode layer (10).
After sputtering is performed to fill the gaps, the surface is flattened by polishing, and the picture electrode layer (9), (
The film thickness is the same as that of 10).

Then, these front electrode layer (9) and rear electrode layer (10
) on which the magnetically sensitive part (8) is formed extends substantially orthogonally to the surface (15) in contact with the magnetic recording medium (not shown), and extends through the insulation N (12d). and is disposed on the substrate, that is, the lower magnetic body (14).

Note that the front end surface of the magnetically sensitive portion (8) and the front end surface of the front electrode layer (9) disposed on the front end thereof are the same as the contact surface (1).
5).

The material of the lower magnetic body (15) is, for example, Ni-
Zn-based ferrite, Mn-Zn-based ferrite, etc. are used. In addition, the material of the insulating layer (12d) may be AlzO3 or SiO, which is used as a normal insulating film.
□ etc. are used.

Further, the above-mentioned front electrode layer (
9) And backwards? The magnetically sensitive part (8) on the opposite side to the flj pole layer (10) is provided with an insulating layer (12b) interposed therebetween. ! ! A bias magnetic field generating conductor (11) for applying a bias magnetic field to the magnetic part (8) is formed.

That is, the bias magnetic field generating conductor (11) has a magnetically sensitive portion (8) located at a position approximately in the middle between the front electrode N (9) and the rear electrode N (10) [the upper part is also f! Magnetic material 13
) is formed on the soft magnetic thin film (8a)),
It is formed to extend across the magnetically sensitive portion (8).

The bias magnetic field generating conductor (11) further extends from both ends thereof in the extending direction of the magnetically sensitive portion (8) to form bias terminal lead-out portions (lla) and (Ilb). . Its bias terminal lead-out part (lla)
.

Terminals T, , T, are provided in a part of (llb), and a current for generating a bias magnetic field is passed between these terminals T, , Tt. Note that the direction of the bias magnetic field generated by the current is such that the direction of magnetization of the soft magnetic thin films (8a) and (8b) of the magnetically sensitive portion (8) is at a required angle with respect to the direction of the sense current, for example, about 45 It is preferable to set the direction so that the angle becomes .

An insulating layer (12c) is interposed on the bias magnetic field generating conductor (11), and an upper magnetic body (13) made of a metallic magnetic material is formed thereon.

The material of the upper magnetic body (13) includes the lower magnetic body (13) described above.
Similar to 14), Ni-Zn ferrite, Mn-Zn ferrite, etc. are used.

For the MR type magnetic head configured as described above, Barkhausen noise can be reduced by selecting the signal magnetic field from the magnetic recording medium and the sense current i flowing through the magnetic sensing part (8) in the same direction. An MR type magnetic hend is realized.

In the MR type magnetic head configured as described above, the front electrode N (9) and the rear electrode layer (10) are formed on the opposite side of the bias magnetic field generating conductor (11) with the magnetic sensing part (8) interposed therebetween. Therefore, the magnetic gap length T can be shortened.

That is, since only the bias magnetic field generating conductor (11) is formed on the magnetically sensitive part (8), conventional MR
Electrode layers (9), (10) and a bias magnetic field generating conductor (1
1), the electrode layer (9
), (10) are not laminated.
) and the upper magnetic body (13) becomes thinner. Therefore, the shield gap length T between the magnetically sensitive portion (8) and the upper magnetic body (13) is shortened.

On the other hand, the front electrode Il! is similarly connected between the magnetically sensitive portion (8) and the lower magnetic body (14). (9) , rear electrode 1'!
Since (10) is simply laminated, the film thickness between them is also thin. Furthermore, even if the thickness of the film in this period is the same as the shield gap length T1 to prevent the reproduced output waveform from becoming asymmetrical, sufficient insulation can be ensured with this thin film. Therefore, the shield gap length T2 between the magnetically sensitive portion (8) and the lower magnetic body (14) is also shortened.

Therefore, the magnetic gap length T of the MR type magnetic head is
is extremely short compared to the conventional one. For example, the magnetic gap length T was conventionally 1.6 μm, but in this example it can be set to 1.0 μm. As a result of a simulation of this magnetic head, when the magnetic gap length T is 1.6 μm, the recording density is such that the reproduction output value of the magnetic head becomes 1/2. The value is 26.4 KF (l), but if the magnetic gap length T is 1.0 μm, it is 33.
7KFCI. In other words, by reducing the magnetic gap length by 0.6 gm, it is about 28%. The value will increase. Therefore, an MR type magnetic head with improved frequency characteristics and suitable for higher recording density is realized. Also, even higher BP
I (maximum bit density) and descendant TPI () rack density)
It will also be possible to respond to

The operation of the magnetic head having the above structure will now be described with reference to FIGS. 3 to 5.

The above-mentioned figures 3 to 5 schematically show only the soft magnetic thin films (8a) and (8b) of the magnetically sensitive part (8), and these soft magnetic thin films (8a) and (8b) are , 3rd
It has an axis of easy magnetization in the initial state in the direction indicated by a in the figure. That is, both terminals 1. ．． 1. When a sense current i is applied between them, an axis of easy magnetization a is perpendicular to the sense current i. By applying a sense current i to these soft magnetic thin films (8a) and (8b), both soft magnetic thin films (8a) facing each other with a non-magnetic intermediate layer (not shown) in between are formed.
, (8b), mutually opposite magnetic fields perpendicular to the sense electric field are generated, which causes both soft magnetic thin films (8a),
(8b) is magnetized as shown by solid line arrow M1 and broken line arrow M2 in the figure.

On the other hand, when a bias magnetic field Hm is applied from the outside to this magnetic sensing part (8) in the direction along the sense current i as shown in FIG. 4, the soft magnetic thin films (8a), (8b ) is indicated by arrow M in Figure 4.
1 and M, by the required angle.

The magnitude of the bias magnetic field H1 is selected so that the direction of magnetization given by the bias magnetic field H8 is approximately 45 degrees with respect to the direction of the sense TL flow i. Note that the bias magnetic field H8 is generated by the bias magnetic field generating conductor (1) described above.
1).

In this way, the bias magnetic field lll1 causes the sense current l
The purpose of providing magnetization at approximately 45° to the magnetic field is to operate in a region where the magnetic field-resistance characteristic curve exhibits high resistance and straightness.
This is similar to what is done for type magnetic heads.

In this state, as shown in FIG. 5, when a signal magnetic field H8 is applied in the direction along the sense current i, that is, in the direction of the hard magnetization axis, the magnetization rotates, and the directions of the respective magnetizations are reversed as shown by arrows MSl and MH2. Angle θ clockwise and clockwise
Rotate 1 and -05 times.

As a result, if the soft magnetic thin films (8a) and (8b) are both MR magnetic thin films, a change in resistance will occur, but the change in resistance of the MR magnetic thin film is due to the change in angle. Since it is proportional to cos'' θ when θ, both soft magnetic thin films (8a) in FIG.
Assuming that the magnetizations M and Mo in (8b) are shifted by 90 degrees from each other, the changes in both soft magnetic thin films (
Regarding 8a) and (8b), the increases and decreases in resistance are the same.

That is, if the resistance of one soft magnetic thin film (8a) increases, the resistance of the other soft magnetic thin film (8b) also changes in the direction of increasing. And these soft magnetic thin films (8a).

(8b) resistance change, that is, the terminals 1 on both sides of the magnetically sensitive part (8). A resistance change occurs between the terminals tI and t2, and this resistance change can be detected as a voltage change between the terminals tI and t2.

Next, in order to make it easier to understand the structure of the MR type magnetic head, a method of manufacturing the magnetic head will be explained with reference to the drawings.

First, as shown in FIG. 6, an insulating Ajl! is placed on a lower magnetic body (14) made of a metal magnetic material such as magnetic ferrite or a substrate. 203 is deposited by normal sputtering, and an insulating layer (12d) is formed so that its Nff is, for example, 3500 (thickness after polishing).

Next, as shown in FIG. 7, a metal conductor of Ti/Cu/Ti is deposited on the insulating layer (12d) in the order of sputtering, and this is patterned by photolithography, for example, etching to form a pattern in the front. Electrode N(
9) and a rear electrode layer <10> are formed.

As a result, the front electrode layer (9) and the rear electrode layer (10
) is formed in a direction substantially perpendicular to the extending direction of the magnetically sensitive part to be formed in a later process, and a front electrode 8i layer (9) is formed at the front end of the magnetically sensitive part and a rear electrode is formed at the rear end of the magnetically sensitive part. A respective layer (10) will be formed.

Further, at the same time as the formation of the front electrode layer (9) and the rear electrode layer (10), terminal lead-out portions (not shown) are formed to extend from both ends of the rear electrode layer (10).

In this example, the film thickness of the metal conductor was initially 200 mm.
After approximately 0 layers were deposited, the surface was flattened by polishing to a film thickness of 1500 layers.

Next, as shown in FIG. 8, A1. tOs is also deposited by sputtering. At that time, the front electrode N (
9) and the rear electrode layer (10) were completely filled with Al z Os, the film thickness of the Al□O3 was set to 2000 layers in this example.

Next, as shown in FIG. 9, the insulation N is removed so that the surfaces of the front electrode layer (9) and the rear electrode layer (10) are exposed.
(12a) is polished.

As a result, the film thickness of the insulation N (12a) becomes the same as the film thickness of the previous front electrode layer (9) and rear electrode layer (10),
These electrode layers (9), (10) and insulating layer (12a
) are flattened and flush. Therefore, the conductive thin film formed thereon is free from short-circuiting and reliability is ensured.

Next, as shown in FIG. 10, the front electrode layer (9), the rear electrode layer (10), the absolute Ii layer (1
2a) Magnetic metal with magnetoresistive effect on top, e.g. Ni
-After depositing Fe, AI! , □0 is sputtered, and Ni--Fe is further deposited.

After that, when these are etched and patterned, both soft magnetic Fit! A magnetically sensitive portion (8) is formed by laminating (8a) and (8b) with a nonmagnetic intermediate layer (8c) interposed therebetween. At this time, the magnetically sensitive portion (8) is formed to extend in a direction substantially perpendicular to the sliding surface with the magnetic recording medium.

In this example, the film thickness of Ni-Fe was set to 300 and 300, respectively.
The film thickness of AlzO3 was set to 40.

Next, as shown in FIG.
isNa is deposited by sputtering and etched to form the insulation N (12b).

Since the above-mentioned 5izNs acts to prevent oxidation of the magnetically sensitive part (8), the reliability can be improved without impairing the function of the magnetically sensitive part (8). In this example, the thickness of the above-mentioned St+Na film was set to 3000.

Next, as shown in FIG. 12, the insulation N (12b)
A conventional metal conductor such as Cu is deposited thereon by sputtering. Next, the metal conductor is etched, and a bias magnetic field generating conductor ( 11).

Note that, at the same time as forming the bias magnetic field generating conductor (11), bias terminal lead-out portions (not shown) are formed extending from both ends thereof. Further, in this example, the film thickness of the metal conductor was 2500.

Next, as shown in FIG. 13, an upper magnetic body (13) is formed on the bias magnetic field generating conductor (11) in a later process.
) is deposited by sputtering to form the insulation Jii (12c).

In this example, the film thickness of 5iOz was set to 4000.

Then, on the insulating layer (12c), an upper magnetic body (13
) to form. Then, after sputtering a plating base film on the upper magnetic body (13), plating is performed. Thereafter, the front end face of the upper magnetic body (13) to the lower magnetic body (14) is polished to polish the front end face (14) that faces the magnetic recording medium.
5) and electrically connects each front end of the magnetically sensitive portion (8) with each other. The front end face of jN (9) is made to face the above-mentioned contact surface (15) to complete the MR type magnetic head shown in FIG.

According to the above process, the process and work process time is small compared to the manufacturing process of an MR type magnetic head in which each electrode layer and a conductor for generating a bias magnetic field are laminated on the same surface of the magnetically sensitive part. Since it can be reduced, manufacturing costs can be reduced.

〔Effect of the invention〕

As is clear from the above description, in the magnetoresistive magnetic head of the present invention, since the electrode layer is formed on the opposite side of the bias magnetic field generating conductor via the magnetic sensing part,
Between the above magnetic sensing part and the upper magnetic body.

Only an electrode layer and a conductor for generating a bias magnetic field are laminated between the magnetically sensitive part and the lower magnetic body, respectively, so that the film thickness between the magnetically sensitive part and the upper magnetic body can be reduced, Similarly, the film thickness between the magnetically sensitive part and the lower magnetic body can be made thinner. Therefore, the magnetic gap length can be shortened.

This makes it possible to improve frequency characteristics and realize an MR type magnetic head suitable for higher recording density.

Furthermore, since the MR type magnetic head of the present invention has a structure in which the magnetically sensitive portion is laminated with a pair of soft magnetic thin films with a nonmagnetic intermediate layer interposed therebetween, the occurrence of Barkhausen noise can be effectively avoided. .

Furthermore, since the MR type magnetic head of the present invention has a structure in which the electrode layer is provided on the opposite side of the bias magnetic field generating conductor via the magnetic sensing part, the manufacturing process can be simplified and the manufacturing cost can be reduced. It is also possible to reduce the

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view of a main part showing an example of a magnetoresistive magnetic head to which the present invention is applied, and FIG. 2 is an enlarged plan view of the main part. Figures 3 to 5 show the operation of the magnetic head to which the present invention is applied. Figure 3 is a schematic diagram showing the direction of magnetization of the soft magnetic yi film in the initial state, and Figure 4 is a diagram when a bias magnetic field is applied. Schematic diagram showing the direction of magnetization of the soft magnetic thin film when
J is a schematic diagram showing the direction of magnetization of a soft magnetic thin film when a signal magnetic field is applied. Figures 6 to 13 show an example of a method for manufacturing the magnetoresistive magnetic head in the order of steps. FIG. 8 is an enlarged cross-sectional view of the main part showing the forming process, FIG. 9 is an enlarged cross-sectional view of the main part showing the polishing process, and FIG. 10 is the magnetically sensitive part forming process. FIG. 11 is an enlarged cross-sectional view of the main part showing the process of forming an insulating layer, FIG. 12 is an enlarged cross-sectional view of the main part showing the process of forming a conductor for generating a bias magnetic field, and FIG. 13 is an enlarged cross-sectional view of the main part showing the process of forming the insulating layer. FIG. 3 is an enlarged sectional view of a main part showing a process. FIG. 14 is an enlarged sectional view of a main part of an example of a conventional magnetoresistive magnetic head. 8...Magnetic sensitive part 9...Front electrode layer 10...Back electrode layer 11...Bias magnetic field generation conductor 13...Top magnetic body 14...Bottom magnetic body Patent applicant Sony Corporation Agent Patent Attorney Kodo Koike Ei Tamura - Masaru Sage Figure 1 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 14 ω 0F
Procedure Nail 11 Seizan (voluntary) June 30, 1988 Director General of the Patent Office Yoshi 1) Tsuyoshi Moon 1, Indication of the case 1988 Patent layer No. 80129 2, Name of the invention Magnetoresistive magnetic head 3 , Relationship with the case of the person making the amendment Patent Applicant Address No. 6-7-35, Kitashinyo, Tokyo Parts Store Name (21
8) Sony Corporation Representative Norio Ohga 4, Agent address 11, 2-6-4 Toranomon, Minato-ku, Tokyo 105
Mori Hill 11th floor k (508) 8266 (?t56
, Column 7 of "Detailed Description of the Invention" of the specification to be amended, contents of the amendment (1) On page 14, line 6 of the specification, after the statement 'Mn-Zn ferrite', 'and metal magnetic Insert a thin film. (2) From line 16 to line 17 of page 15 of the same book
``Mn-Zn ferrite'' is followed by ``and metal magnetic thin film''. that's all

Claims (1)

[Scope of Claims] A magnetically sensitive part in which a pair of soft magnetic thin films, at least one of which has a magnetoresistive effect, are laminated on a substrate with a nonmagnetic intermediate layer interposed therebetween, and a front end and a rear end of the magnetically sensitive part. A front electrode layer and a rear electrode layer are respectively deposited on the magnetically sensitive portion, and a bias magnetic field generating conductor is provided that extends across the magnetically sensitive portion via an insulating layer, and the front electrode layer and the rear electrode layer are provided with a conductor for generating a bias magnetic field. A magnetoresistive magnetic head, characterized in that the magnetoresistive head is disposed on the opposite side of the bias magnetic field generating conductor with the magnetic sensing section interposed therebetween.