JPH06203332A - Compoite type thin-film magnetic head - Google Patents

Abstract

PURPOSE:To provide the high-performance head by arranging a nonmagnetic conductor film passing current in the direction reverse from the direction of the sense current to be passed to a magneto-resistance effect element opposite to the magneto-resistance effect element so as to overlap thereon via an interlayer insulating layer. CONSTITUTION:A spiral coil for recording consisting of a Cu film held by second and third nonmagnetic insulating films 14b, 14c consisting of Al2O3, etc., is provided between a first magnetic pole 13 and second magnetic pole 18 which consist of NiFe films and are commonly used as magnetic shields. A pair of leader conductors 16b (16a) consisting of Cu films, etc., are joined to delineate a signal detecting region (not shown in Fig.). The nonmagnetic conductor film 31 which has the same shape as the shape of the signal detecting region 15a of the magneto-resistance effect element 15 consisting of the NiFe film and consist of the 4u or Au, Ti film, etc., joined with the leader conductors 32a, 32b respectively on both sides thereof is provided via the interlayer insulating layer 33 consisting of the Al2O3, etc., near the element 15 opposite to the element 15 so as to overlap thereon. The magnetization of the first and second magnetic poles 13, 18 is prevented by passing the sense current to the effect element 15 and simultaneously passing the current reverse from the sense current to the nonmagnetic conductor film 31 at the time of reproduction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite thin film magnetic head composed of a thin film inductive head and a magnetoresistive thin film head used in a magnetic disk device or a magnetic tape device.

2. Description of the Related Art In a magnetic disk device or the like, a high performance thin film magnetic head capable of high density recording and high reproduction output is required as the size and the capacity are increased. Therefore, the reproduction output as a reproduction-only magnetic head does not depend on the speed of the recording medium, can be applied to a small magnetic disk, and can provide a high reproduction output, and a reproduction-only magnetoresistive thin film head (MR head). Attention has been paid to a composite type thin film magnetic head in which a thin film inductive head is also used for recording and is integrated as a recording / reproducing head.

However, since the composite type causes an obstacle that the information recorded on the magnetic recording medium is erased at the time of reproduction, a reliable composite type thin film which eliminates the occurrence of such an obstacle. A magnetic head is needed.

[0004]

2. Description of the Related Art A conventional composite type thin film magnetic head is shown in FIG.
As shown in the sectional side view, for example, Al₂O ₃・ From TiC, etc.
Al on the non-magnetic substrate 11₂O₃Through the insulating layer 12 consisting of
The first magnet that also functions as a magnetic shield composed of a NiFe film that is arranged
Al between the pole 13 and the second magnetic pole 18 ₂O₃First non-magnet consisting of etc.
The leading end faces the magnetic recording medium 21 via the insulating film 14a.
Exposed on the tip surface of the head and the signal detection area (not shown).
Pair of lead conductors made of Cu film, etc.
Magnetoresistive effect of NiFe film formed by joining 16b and (16a)
Element (MR element) 15 and Al₂O₃2nd and 3rd non-consisting of
Spiral made of Cu film sandwiched between magnetic insulating films 14b and 14c
A recording coil 17 in the shape of a ring is arranged, and is placed on the second magnetic pole 18.
Is Al₂O₃An insulating protective film 19 made of a film or the like is covered.

The first magnetic pole 13 and the second magnetic pole 18 are narrowed at their tips so as to sandwich a predetermined magnetic gap from the tips of the MR element 15, and their rear ends are magnetically coupled. Has become.

At the time of recording, a recording signal current is passed through the recording coil 17 to magnetize the first magnetic pole 13 and the second magnetic pole 18 as in a general inductive head, and the first magnetic pole 13 is recorded.
Information is magnetically recorded on the opposing magnetic recording medium 21 by the recording magnetic field leaking from the magnetic gap between the tip of the second magnetic pole 18 and the magnetic pole. During reproduction, a leakage magnetic field from the first magnetic pole 13 magnetized by a magnetic field generated by flowing a sense current through the MR element 15 is applied to the MR element 15 as a bias magnetic field.

The magnetization of the MR element 15 is changed by the magnetic field from the magnetic recording medium 21, and M generated by the magnetoresistive effect.
The change in the electric resistance value of the R element 15 is controlled by the pair of lead conductors 16
Playback is performed by detecting the playback signal as a voltage change from b, (16a).

[0008]

By the way, in the composite type thin film magnetic head having such a structure, the structure of the MR element 15 and the pair of lead conductors 16b and (16a) joined thereto forms one turn coil. Therefore, the first magnetic pole 13 and the second magnetic pole 18, which are magnetically coupled by the magnetic field generated by flowing the sense current through the MR element 15 at the time of reproduction, are magnetized, and from the gap between the tips of the both magnetic poles. Hundreds of Oersted (Oe)
There is a problem that the following magnetic field may leak and demagnetize the information magnetization recorded in the opposing magnetic recording medium 21.

In view of the above-mentioned conventional problems, the present invention prevents the first and second magnetic poles from being magnetized by a magnetic field generated by flowing a sense current through an MR element during reproduction, and is recorded on a magnetic recording medium. It is an object of the present invention to provide a novel composite type thin film magnetic head that eliminates the demagnetization of the existing recording magnetization.

[0010]

In order to achieve the above-mentioned object, the present invention provides a magnetic pole that also serves as two magnetic shields.
A magnetoresistive element including a recording coil and a pair of lead conductors joined to each other with a tip end facing a magnetic recording medium via a nonmagnetic insulating film and defining a signal detection region. In the arranged head configuration, in the vicinity of the magnetoresistive effect element formed by joining the pair of lead conductors, the lead conductors are joined in the same shape as the signal detection region of the magnetoresistive effect element on both sides thereof. In addition, a non-magnetic conductor film that causes a current to flow in a direction opposite to the direction of the sense current flowing through the magnetoresistive effect element is arranged so as to face the magnetoresistive effect element so as to overlap with the magnetoresistive effect element via an interlayer insulating layer.

The magnetoresistive effect element is provided so as to be recessed from the tip end surface of the head facing the magnetic recording medium, and the flux magnetically coupled to the magnetoresistive effect element is provided between the magnetoresistive effect element and the tip end surface of the head. The guide is arranged.

[0012]

According to the present invention, a pair of extraction conductors are joined between the magnetic poles which also serve as two magnetic shields so as to define the signal detection area which is arranged with the recording coil via the non-magnetic insulating film. The MR element is provided in the vicinity of the resistance effect element (MR element) or is set back from the tip end surface of the head facing the magnetic recording medium, and a flux guide is provided between the MR element and the head tip surface of the head. In the vicinity of the MR element, which is arranged in a state of being mechanically coupled,
A non-magnetic conductor film, which has the same shape as the signal detection region of the MR element and has lead conductors joined in the same shape on both sides thereof, is arranged so as to face the MR element with an interlayer insulating layer interposed therebetween. A magnetic field generated in the MR element cancels out a magnetic field generated in the non-magnetic conductor film by causing a sense current to flow in the non-magnetic conductor film at the same time as a sense current flows in the MR device. As a result, it is possible to prevent magnetizing the magnetic pole that also serves as the two magnetic shields. As a result, it is possible to eliminate the demagnetization of the recording magnetization recorded in the magnetic recording medium corresponding to the two magnetic poles.

[0013]

Embodiments of the present invention will be described in detail below with reference to the drawings. 1 is a side sectional view of an essential part showing an embodiment of a composite type thin film magnetic head of the present invention, and the same parts as those in FIG. 4 are designated by the same reference numerals.

[0014] In the embodiment shown in this figure, between the first pole 13 and second pole 18 which also serves as a magnetic shield made of NiFe film, the second, third nonmagnetic insulating film 14b made of Al ₂ O ₃ or the like , 14c
Spiral recording coil made of Cu film sandwiched between
A magnetoresistive effect element (MR element) made of a NiFe film formed by joining a pair of lead conductors 16b, (16a) made of a Cu film or the like so as to define a signal detection region (not shown) arranged together with 17. As shown in FIG. 2, in the vicinity of 15 through the interlayer insulating layer 33 made of Al ₂ O ₃ or the like, the same shape as the signal detection region 15a of the MR element 15 and the lead conductors 32a, 32b on both sides thereof are formed. A non-magnetic conductor film 31 made of a Cu film, an Au film, a Ti film, or the like bonded to the MR element 15 is arranged so as to face the MR element 15.

At the time of recording, a recording signal current is passed through the recording coil 17 to magnetize the first magnetic pole 13 and the second magnetic pole 18 whose rear ends are magnetically coupled, as in the conventional case.
Information is magnetically recorded on the opposing magnetic recording medium 21 by the recording magnetic field leaking from the magnetic gap between the tips of the first and second magnetic poles 13 and 18.

During reproduction, a sense current is passed through the MR element 15 and at the same time a current is passed through the non-magnetic conductor film 31 in a direction opposite to the direction of the sense current passed through the MR element 15. The magnetic field generated by flowing the sense current is canceled by the magnetic field generated by flowing a current in the direction opposite to the direction of the sense current in the non-magnetic conductor film 31, and a bias magnetic field is applied to the MR element 15. The magnetization of the first magnetic pole 13 and the second magnetic pole 18, which also serve as the two magnetic shields, is prevented.

Therefore, it becomes possible to eliminate the demagnetization of the recording magnetization recorded in the magnetic recording medium corresponding to the two magnetic poles. In this way, the magnetic field generated by passing the sense current through the MR element 15 is canceled and the MR element 15
The effect of applying a bias magnetic field to the MR element 15 is that the lead conductors 16b and (16a) are joined to the signal detection region 15a of the MR element 15 and both sides thereof, and the lead conductors 32a and 16a are joined to the non-magnetic conductor film 31 and both sides thereof, respectively. It is most prominent when the shape and area of 32b are the same.

FIG. 3 is a side sectional view of a main part showing another embodiment of the composite type thin film magnetic head of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals. The embodiment shown in this figure is different from the first embodiment shown in FIG. 1 in that a pair of lead conductors 16b and (16a) made of a Cu film or the like are joined so as to define the signal detection region (not shown). MR element consisting of NiFe film
Is provided so as to be recessed from the front end surface of the head facing the magnetic recording medium 21, and a flux guide made of, for example, a corrosion-resistant NiFeCr film is provided between the MR element 15 and the front end surface of the head.
41 is arranged in a state of being magnetically coupled to the MR element 15 through an insulating thin film (not shown), and the lead conductors 32b are formed in the vicinity of the MR element 15 and have the same shape as the signal detection region of the MR element 15 on both sides thereof. Non-magnetic conductor film with (32a) bonded in the same shape
The point is that 31 is arranged so as to face the MR element 15 with the interlayer insulating layer 33 interposed therebetween.

Even with the composite thin film magnetic head having such a structure, the magnetic field generated by flowing a sense current through the MR element 15 is the same as in the embodiment shown in FIG.
A magnetic field generated by flowing a current in the direction opposite to the sense current in 31 cancels out, and a bias magnetic field is applied to the MR element 15, and the first magnetic pole 13 also functions as the two magnetic shields. The magnetization of the second magnetic pole 18 is prevented, and the demagnetization of the recorded magnetization of the corresponding magnetic recording medium can be eliminated.

Further, in this structure, since the tip of the MR element 15 is not exposed at the tip of the head facing the magnetic recording medium 21, there is no fear of corrosion and abrasion, and the magnetic flux coupling guide 41 is used. Is electrically insulated, there is no possibility of electrical damage or noise due to contact of the MR element 15 through which the sense current flows with the magnetic recording medium 21.

[0021]

As is apparent from the above description, according to the composite type thin film magnetic head of the present invention, the magnetic field generated by flowing the sense current through the MR element has the same shape as the MR element. While canceling by a magnetic field generated by flowing a current in a direction opposite to the direction of the sense current in the non-magnetic conductor film arranged so as to overlap with 15,
A bias magnetic field is applied to the MR element to prevent the first and second magnetic poles that also function as the two magnetic shields from being magnetized, so that the recording magnetizations of the magnetic recording medium corresponding to these magnetic poles are recorded. It has an excellent advantage that the demagnetization can be easily eliminated, and a highly practical high-performance composite type thin film magnetic head can be realized, and the practical effects are large.

[Brief description of drawings]

FIG. 1 is a side sectional view of an essential part showing an embodiment of a composite type thin film magnetic head of the present invention.

FIG. 2 is a magnetoresistive element according to an embodiment of the present invention.
It is a schematic perspective view for explaining the relationship between (MR element) and a conductor film.

FIG. 3 is a side sectional view of an essential part showing another embodiment of the composite type thin film magnetic head of the present invention.

FIG. 4 is a side sectional view of an essential part for explaining a conventional composite type thin film magnetic head.

[Explanation of symbols]

 11 non-magnetic substrate 12 insulating layer 13 first magnetic pole 14a first non-magnetic insulating film 14b second non-magnetic insulating film 14c third non-magnetic insulating film 15 MR element 16b (16a), 32b (32a) lead conductor 17 recording coil 18 Second Magnetic Pole 19 Insulating Protective Film 20, 34 Medium Facing Surface 21 Magnetic Recording Medium 31 Non-Magnetic Conductor Film 33 Interlayer Insulating Layer 41 Flux Guide

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoko Kusawa, 1015 Kamiodanaka, Nakahara-ku, Kawasaki, Kanagawa Prefecture, Fujitsu Limited (72) Inventor Hidekazu Tanaka, 1015, Kamikodanaka, Nakahara-ku, Kawasaki, Kanagawa Prefecture, Fujitsu Limited

Claims (2)

[Claims] 1. A magnetic pole (13, 1) which also serves as two magnetic shields.
8), the recording coil (17) is provided via the non-magnetic insulating films (14a, 14b, 14c) respectively, and the tip portion is provided so as to face the magnetic recording medium (21), and the signal detection area is provided. In a head configuration in which a magnetoresistive effect element (15) formed by joining a pair of lead conductors (16a, 16b) is arranged so as to define, a magnetic resistance formed by joining the pair of lead conductors (16a, 16b) In the vicinity of the effect element (15), the same shape as the signal detection region of the magnetoresistive effect element (15) and the lead conductors (3
2a, 32b) are joined in the same shape, and the magnetoresistive element (1
The non-magnetic conductor film (31) for flowing a current in the direction opposite to the direction of the sense current flowing in (5) is arranged so as to face the magnetoresistive element (15) via the interlayer insulating layer (33). And a composite type thin film magnetic head. 2. The magnetoresistive effect element (15) is provided so as to be retracted from a tip end surface of a head facing the magnetic recording medium (21),
A flux guide magnetically coupled to the magnetoresistive effect element (15) between the magnetoresistive effect element (15) and the tip surface of the head.
The composite thin-film magnetic head according to claim 1, wherein (41) is arranged.