JPH06215321A - Dual magnetic head - Google Patents

Abstract

PURPOSE:To prevent an element from being etched and to provide a stable reproducing characteristic by constituting so that the element does not exposed to the oposite surface of a magnetic disk in the dual magnetic head using a magnetic resistant element. CONSTITUTION:A ground insulated film 2 is formed on a ceramic substrate 1 and the lower shielded film 3 consisting of the magnetic film such as Ni and Fe is provided on this, and also the lower gap film 4 consisting of the insulated film such as alumina is formed on this. Then, a magneto-resistance effect film 6 is formed on the film 4 by separating a distance L from the floating surface F of a disc and the insulated film 5 such as alumina is provided between the film 6 and the floating surface F. And an electrode electrically conductive layer 7 is formed on the part of the film 5, 6 and 4, and a current is made to flow through the film 6, and the film 6 is allowed to work as a senor. And also, an upper gap film 8 is formed on the part of a condactive material 7, the film 5, 6 and 4, the upper part shielded film 9 formed by the magnetic film of NiFe and an alumina insulated film 10 as a protecting, film is formed on this, and the lower part magnetic film 11 such as + or -aermalloy'(R) is formed on this.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dual magnetic head used in a magnetic recording device, and more particularly to a dual magnetic head using a magnetoresistive effect element (hereinafter referred to as MR element) in a reproducing section.

[0002]

2. Description of the Related Art A dual magnetic head using an MR element as a reproducing portion utilizes a characteristic that the resistance value of the MR element changes depending on the strength of a magnetic field, and reproduces and outputs from a magnetic recording medium such as a magnetic disk. Is what you get. In the reproduction using the MR element, the reproduction output does not depend on the magnetic recording medium running speed and is determined only by the wavelength of the magnetic signal, so that a sufficient reproduction output can be obtained even at a low speed, and the magnetic recording apparatus can have a high density and a small size. Is advantageous to.

The width of the MR element (stripe width) is one of the parameters that greatly affects the reproduction efficiency of the MR element. As a method of determining the stripe width, for example, as disclosed in Japanese Patent Laid-Open No. 3-238614, the MR element is once formed to have a width larger than the intended stripe width, and then the air bearing surface wrap (the surface facing the magnetic recording medium) is machined. Of the MR element and shaving the MR element to obtain a predetermined stripe width.

[0004]

In the above-mentioned conventional technique, the stripe width of the MR element varies within the accuracy range of machining, which causes a reduction in reproduction efficiency. Further, since the MR element is exposed on the surface facing the magnetic recording medium, the structure is easily corroded.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to provide a dual magnetic head in which an MR element is unlikely to corrode and a stripe width can be formed with high accuracy. is there.

[0006]

In order to achieve the above object, a dual magnetic head of the present invention is a dual magnetic head in which an MR element and a write element are formed on a substrate by a thin film laminating method. It is characterized in that it is not exposed on the surface of the head facing the magnetic recording medium.

Such a dual magnetic head is manufactured by separating the MR element from the magnetic recording medium facing surface by a photolithography technique, and then machining the magnetic recording medium facing surface so as not to scrape the MR element. It

[0008]

In the dual magnetic head of the present invention, since the MR element is not exposed on the surface facing the magnetic disk, corrosion of the MR element is less likely to occur. Further, since the stripe width of the MR element is determined only by the thin film technology without using mechanical processing, the MR element has a much higher precision than the conventional technology. Therefore, stable reproduction characteristics can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 is an explanatory diagram showing a main part of the dual magnetic head element of the present embodiment.
In FIG. 1, 1 is a ceramic substrate, 2 is a base insulating film,
Reference numeral 3 is a base shield film, 4 is a base gap film, 6 is a magnetoresistive film, 7 is an electrode conductor layer, and F is an air bearing surface (a magnetic recording medium facing surface) for a magnetic disk (not shown).

As shown in FIG. 1, in this embodiment, the magnetoresistive film 6 having a stripe width W is formed so as to recede from the air bearing surface F by a distance L. Although not shown in FIG. 1, more thin films are laminated on the electrode conductor layer 7, the underlying gap film 4, and the magnetoresistive effect film 6.
Further, in FIG. 1, the lower shield film 3 and the lower gap film 4 are shown in a cross section which is aligned with the end faces of the magnetoresistive effect film 3 and the electrode conductor layer 7, but the lower shield film 3 and the lower gap film 4 are It has the same width as the ceramic substrate 1.

FIG. 2 is a sectional view of the dual magnetic head element shown in FIG. 1 taken along a plane S1 including the electrode conductor layer 7. In the cross-sectional view shown in FIG. 2, many thin films omitted in FIG. 1 are shown.

FIG. 3 is a sectional view of the dual magnetic head element shown in FIG. 1 taken along a plane S2 not including the electrode conductor layer 7. In the sectional view shown in FIG.
Similarly, many thin films that have been omitted in FIG. 1 are shown.

The difference between FIG. 2 and FIG. 3 is mainly due to the presence or absence of the electrode conductor layer 7 and the presence or absence of the electrode 16, as is apparent from the planes S1 and S2 of FIG. Are almost the same.

As shown in FIGS. 1 to 3, a base insulating film 2 is formed on a ceramic substrate 1, and Ni is formed on the base insulating film 2.
A lower shield film 3 made of a magnetic film such as Fe is formed. Further, the lower gap film 4 made of an insulating film such as alumina is continuously formed on the base shield film 3. next,
The magnetoresistive effect film 6 is formed on the base gap film 4 at a distance L from the air bearing surface F of the magnetic disk. In this example, as shown in FIGS. 2 and 3, the magnetoresistive effect film 6 is formed from a position deeper than the origin (point of Gd = 0) of the gap distance Gd of the magnetic gap film 12 which is the write head element. (Gd <L), the air bearing surface F is prevented from being machined. Therefore, the accuracy of the stripe width W of the magnetoresistive effect film 6 is highly accurate because it is determined by the forming accuracy of itself, that is, the photolithography technique. Then, on the lower gap film 4 and between the magnetoresistive effect film 6 and the air bearing surface F, as shown in the figure, an insulating film 5 made of alumina or the like is used.
Is formed.

Further, on the insulating film 5, the magnetoresistive film 6 and the lower gap film 4, as shown in FIG.
The electrode conductor layer 7 is formed. The electrode conductor layer 7 supplies the current to the magnetoresistive effect film 6 in order to make the magnetoresistive effect film 6 act as a sensor, and is connected to the terminal 16. As described above, the cross-sectional view shown in FIG.
The electrode conductor layer 7 is not formed. In addition, FIGS.
Although not shown in FIG. 3, a magnetic domain control film for controlling the magnetic domains of the magnetoresistive effect film 6 is formed simultaneously with the magnetoresistive effect film 6.

Further, an insulating film such as alumina is formed on the electrode conductor layer 7 (FIG. 2) and on the insulating film 5, the magnetoresistive film 6 and a part of the lower gap film 4 (FIG. 3). An upper gap film 8 is formed, and an upper shield film 9 formed of a magnetic film such as NiFe and an insulating film 10 such as alumina as a protective film are formed on the upper gap film 8.
Are formed in order. Then, a magnetic film such as permalloy is laminated on the insulating film 10 by sputtering, and a pattern is formed by a dry etching method such as ion milling to form the lower magnetic film 11.

Next, the magnetic gap film 12 is formed, the interlayer insulating film 13 and the conductor coil 14 are sequentially formed, and the interlayer insulating film 13 is etched to obtain a predetermined shape. further,
A magnetic film such as permalloy is laminated by sputtering, and a pattern is formed by a dry etching method such as ion milling to form the upper magnetic film 15.

The steps up to this point complete the formation of the core portion of the device. Finally, a terminal 16 for connecting the lead wire
To complete the device process.

Next, regarding the air bearing surface F of the magnetic head, in this step, the air gap surface Gd of the magnetic gap film, which is the write head element, is machined to an appropriate value. Here, an appropriate value is, in terms of regeneration efficiency,
It is desirable to process L to about 3 μm or less. In this embodiment, the magnetoresistive effect film 3 has the gap distance G
Since it is formed deeper than the position of d = 0, it is not directly ground by machining and the magnetoresistive effect film 6 is not exposed on the air bearing surface F.

FIG. 4 is a sectional view showing the entire thin film head having the dual magnetic head element manufactured according to this embodiment. In the drawing, 18 indicates a dual magnetic head element.

The accuracy of the stripe width W of the magnetoresistive effect film 6 in the dual magnetic head thus manufactured is suppressed to ± 0.5 μm or less, which is ± 1.0 of the prior art.
The accuracy is significantly improved as compared with about μm, and stable reproduction characteristics can be obtained.

Although the insulating layer 5 is provided between the magnetoresistive effect element 6 and the air bearing surface F in the above embodiment, the present invention is not limited to this, and an inorganic layer or the like may be provided. good.

In the above embodiment, the insulating film 5 is formed separately from the lower gap film 4 and the upper gap film 8. However, the present invention is not limited to this, and the insulating film 5 is formed in the lower gap film. It may be formed integrally with the film 4 or may be formed integrally with the upper gap film 7.

Further, in the above embodiment, the magnetoresistive effect element 6 is not entirely exposed to the air bearing surface F, but the magnetoresistive effect element 6 is used to improve the reproduction efficiency.
A part of the above may be exposed to the air bearing surface F.

In the above embodiment, the dual magnetic head used in the magnetic disk device is described as an example.
The present invention is not limited to this, and can be widely applied to a magnetic head used for a magnetic recording medium such as a magnetic tape device.

[0026]

According to the present invention, since the MR element is not exposed on the surface facing the magnetic recording medium, corrosion is unlikely to occur, and the stripe width value is determined without machining.
Compared with the conventional technique, the precision is remarkably high, and stable reproduction characteristics can be obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a main part of a dual magnetic head element.

FIG. 2 is a cross-sectional view of the dual magnetic head element shown in FIG. 1 taken along a plane S1 including an electrode conductor layer 7.

FIG. 3 is a cross-sectional view of the dual magnetic head element shown in FIG. 1 taken along a plane S2 that does not include an electrode conductor layer 7.

FIG. 4 is a sectional view showing an entire thin film head including the dual magnetic head element shown in FIGS. 1 to 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Ceramic substrate, 2 ... Base insulating film, 3 ... Lower shield film, 4 ... Lower gap film, 5 ... Insulating film, 6 ... Magnetoresistive film, 7 ... Electrode conductor layer, 8 ... Upper gap film, 9 ... Upper part Shield film, 10 ... Insulating film, 11 ... Lower magnetic film, 12
... magnetic gap film, 13 ... interlayer insulating film, 14 ... conductor coil, 15 ... upper magnetic film, 16 ... terminal, 18 ... dual magnetic head element.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shunichiro Hozuka 2880 Kozu, Odawara City, Kanagawa Stock Company Hitachi Storage Systems Division

Claims (3)

[Claims] 1. A dual magnetic head having a magnetoresistive effect element and a write element formed on a substrate by a thin film laminating method, wherein the magnetoresistive effect element is not exposed on a surface of the dual magnetic head facing a magnetic recording medium. Characteristic dual magnetic head. 2. The dual magnetic head according to claim 1, wherein an insulating layer is provided between the magnetoresistive effect element and the surface facing the magnetic recording medium. 3. A gap between the magnetoresistive effect element and a magnetic recording medium facing surface is 3 μm or less.
The described dual magnetic head.