JPH0660326A - Thin film magnetic head and its production - Google Patents

Abstract

PURPOSE:To maintain a satisfactory insulating property even at the time of reducing the gap between shield layers. CONSTITUTION:With respect to the thin film magnetic head where a lower gap insulating layer 32, an MR film 31, a protective insulator 34 for this film 31, a lead 26, and an upper gap insulating layer 33 are successively laminated between a lower shield layer 30 and an upper shield layer 35, the upper face of the protective insulator 34 and that of the lead 26 are so flattened that they are placed in the same plane. The MR film 31 is formed on the lower shield layer 30 through the lower gap insulating layer 32 between them, and the insulator 34 to protect the MR film 31 from etching is formed in a prescribed part on the MR film 31, and the lead 26 is formed on the insulator 34 and the MR film 31, and upper faces of the lead 26 and the insulator 34 are flattened. The upper shield layer 35 is formed on these upper faces with the upper gap insulating layer 33 between them.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetoresistive head (Magneto) for reproducing from a magnetic medium such as a magnetic disk.
The present invention relates to a thin film magnetic head having at least a resistive head (hereinafter referred to as an MR head) and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, MR heads have begun to be put into practical use as thin film magnetic heads for magnetic media such as magnetic disks. The MR head uses the magnetoresistive effect that the electric resistance changes depending on the magnetization, and by its nature,
Providing shield layers on both sides to block unnecessary magnetic fields,
It is configured by providing an MR element and an MR lead with a gap insulating layer interposed therebetween.

FIG. 5 schematically shows a part of a conventional thin-film magnetic head constructed by combining a reproducing MR head and a recording inductive head from the bottom side facing the magnetic medium. is there.

In the figure, reference numeral 50 denotes a lower shield layer formed on the rear end surface side of the flying slider via an insulating underlayer film (not shown). The lower shield layer 50 and the upper shield layer 55 are composed of Between the lower gap insulating layer 5
2. An MR film 51 of an MR element, an insulator 54 for protecting the MR film 51 from etching, a lead 56, and an upper gap insulating layer 53 are sequentially laminated. On the reproducing MR head thus formed, the recording inductive head having the lower magnetic layer 66 and the upper magnetic layer 69 as its core is laminated.

[0005]

In the conventional MR head of this type, a protective insulator 54 is formed on a portion of the MR film 51 corresponding to the read track width, and a lead 56 is formed thereon. Therefore, as shown in FIG.
A step is created between the lead 56 and the insulator 54.
Then, since the upper gap insulating layer 53 is laminated on this, insulation is incomplete at the step portion, and when the film thickness of the upper gap insulating layer 53 is reduced, the lead 56 and the upper shield layer 55 are short-circuited. There arises a problem that current leakage is caused and head characteristics are significantly deteriorated.

In particular, in order to improve the resolution of the MR head, the distance between the lower shield layer 50 and the upper shield layer 55 is set to the bit distance of the recording magnetization on the magnetic medium (magnetization reversal distance).
It is necessary to keep the value below a little smaller value, and this magnetization reversal distance becomes several thousand Å in high density recording.
Assuming that the thickness of the MR element including the MR film 51 is about 2000 Å, the thickness of the upper gap insulating layer 53 is 0.1.
Since it is required to be about μm, it becomes a more serious problem.

Therefore, the present invention provides a thin film magnetic head capable of maintaining a good insulating property even when the distance between the shield layers is reduced, and a method of manufacturing the same.

[0008]

According to the present invention, a lower gap insulating layer, an MR film, a protective insulator for the MR film, leads, and an upper gap insulating layer are provided between the lower shield layer and the upper shield layer. A thin film magnetic head in which the upper surface of the protective insulator and the upper surface of the lead are flattened in substantially the same plane.

An inductive head may be laminated on the above-mentioned upper shield layer.

According to the present invention, the MR film is formed on the lower shield layer with the lower gap insulating layer interposed therebetween.
An insulator that protects the MR film from etching is formed at a predetermined portion on the R film, leads are formed on the insulator and the MR film, the upper surfaces of the lead and the insulator are flattened, and these flattened upper surfaces are formed. Provided is a method of manufacturing a thin film magnetic head, on which an upper shield layer is formed via an upper gap insulating layer.

It is preferable that the above-mentioned flattening is performed by an etch back method.

An inductive head may be formed on the upper shield layer described above.

[0013]

After the lead is formed on the insulator and the MR film,
Since the upper surfaces of the lead and the insulator are flattened and the upper gap insulating layer is formed on these flattened upper surfaces, the upper gap insulating layer becomes flat and the insulating property is reduced even if the film thickness is reduced. Will be sufficiently maintained. Further, the shape of the magnetic layer (core) of the inductive head formed thereabove is free from distortion, and the writing efficiency is improved.

[0014]

The present invention will be described in detail with reference to the following examples.

FIG. 2 is a perspective view showing a flying type magnetic head unit provided with a composite type thin film magnetic head as one embodiment of the present invention.

As shown in the figure, the flying type magnetic head unit of this embodiment comprises a slider 20 and two thin film magnetic heads provided on its rear end face (with respect to the relative traveling direction of the head unit to the magnetic medium). 21 and its protective film 22. The slider 20 is
For example, a ceramic structure 23 made of a ceramic material such as Al ₂ O ₃ —TiC and a base film 24 formed by sputtering an electrically insulating material such as Al ₂ O ₃ or SiO _{2 on} the rear end surface of the ceramic structure 23. It is configured.

The thin film magnetic head 21 is a thin film element formed on the base film 24, and the head 21 has a protective film 2 formed thereon.
Four electrodes 25 formed so as to be exposed on the surface of No. 2 are connected via four leads 26, respectively.

The protective film 22 is formed by sputtering Al ₂ O ₃ or SiO ₂ or the like, and is formed so as to cover the entire surfaces of the thin film magnetic head 21, the base film 24, and the leads 26.

FIG. 3 is a partial sectional view taken along the line AA of FIG. 2 to show the structure of the thin film magnetic head 21 in more detail.

A lower shield layer 30 is formed on the base film 24 formed on the rear end surface of the ceramic structure 23 described above, and a lower gap insulating layer 32 is formed on the lower shield layer 30. The MR film 31 made of permalloy or the like is formed thereon. MR film 31
An insulator 34 for protecting this film from etching or the like is formed on the top. The lead 26 (FIG. 2) is formed on it. The upper surfaces of the insulator 34 and the lead 26 are
After being flattened as described later, the upper gap insulating layer 3
3 is formed. An upper shield layer 35 is formed on the upper gap insulating layer 33.

The lower shield layer 30, the lower gap insulating layer 32, the MR film 31, the insulator 34, the lead 26, the upper gap insulating layer 33, and the upper shield layer 35 constitute a reproducing MR head portion. Upper shield layer 35
An insulating film 37 is formed on top by sputtering Al ₂ O ₃ or the like.

A lower magnetic layer 46 is formed on the insulating film 37 by plating a soft magnetic film such as permalloy, and an insulating film 4 such as Al ₂ O ₃ or SiO ₂ is formed thereon.
A coil conductor 48 made of Cu, Au, or the like is provided between the electrodes 7 and 7, and an upper magnetic layer 49 is formed on the coil conductor 48 by plating a soft magnetic film such as permalloy.

The lower magnetic layer 46 and the upper magnetic layer 49 are connected to each other at a portion 49a on the side opposite to the surface B facing the magnetic medium, and thus constitute the core of the inductive head portion for recording. . The coil conductor 48 is formed so as to be spirally wound around the coupling portion 49a of the lower magnetic layer 46 and the upper magnetic layer 49.

The protective film 22 described above is formed on the upper magnetic layer 49.

The lower magnetic layer 46 is the upper shield layer 3.
It is obvious that the dual-purpose structure may be used so as to fulfill the function of 5. In this case, as a matter of course, the insulating film 37 is omitted.

FIG. 1 schematically shows the thin film magnetic head 21 in this embodiment from the bottom surface side (the surface B side in FIG. 3) facing the magnetic medium, and FIG. 4 shows its manufacturing process. There is.

First, referring to FIG. 4A, the base film 24
(FIG. 3) The lower shield layer 30 is formed by plating a soft magnetic film such as permalloy on the top. The lower shield layer 30 is provided so as to cover at least the element region of the MR film 31, and is formed with a film thickness of about 1 to 2 μm.

Al ₂ O is formed on the lower shield layer 30.
_The lower gap insulating layer 32 is formed by sputtering ₃
Are laminated.

On the lower gap insulating layer 32, permalloy or the like is sputtered to form M having a film thickness of about 300 to 600 Å.
After forming the R film 31 and further sputtering Ti to form a shunt layer having a film thickness of about 500 to 1500 Å for applying a bias, these are patterned to form an MR element. A soft film bias layer or the like may be formed instead of the shunt layer. The film forming order may be reversed.

The MR film 31 is included in a predetermined range that determines the read width on the MR element from the etching (ion milling or the like) when the lead and the upper gap insulating layer are formed later.
An insulator 34 'is formed to protect the substrate. This insulator 34 'is formed by sputtering Al ₂ O ₃ to have a film thickness of about 0.1 μm.

Then, as shown in FIG.
4 ′, the MR film 31, and the lower gap insulating layer 32,
Leads 26 'are formed. This lead 26 'is made of Cu
Etc. are formed by plating and patterning a film having a film thickness of about 0.3 μm.

After forming the MR lead 26 ', the lead 26' is applied by a flattening technique such as an etch-back method in which a resist is applied to remove the convex portion together with the resist etching.
And a flattening process so that the upper surfaces of the insulators 34 'are substantially in the same plane. FIG. 4 shows a state in which the height of the lead 26 and the height of the insulator 34 are substantially equalized by the flattening process.
It is shown in (C).

Next, as shown in FIG. 4D, an upper gap insulating layer 33 is laminated on the upper gap insulating layer 33 by sputtering Al ₂ O ₃ or the like, and at least the MR element on the upper gap insulating layer 33 is formed. The area that covers is coated with a soft magnetic film such as Permalloy to 1.5-
The upper shield layer 35 having a film thickness of about 3 μm is formed.

As shown in FIG. 1, a lower magnetic layer 46 is formed on the upper shield layer 35 via the insulating film 37 (FIG. 3) described above, and an insulating film 47 (FIG. 3) is formed thereon. )
The upper magnetic layer 49 is formed so as to sandwich the coil conductor 48 (FIG. 3).

As described above, according to the present embodiment, after the MR lead 26 'is formed, the flattening process is performed to reduce or substantially eliminate the step in the insulator 34' portion. In other words, Since the upper surfaces of the lead 26 and the insulator 34 are located substantially in the same plane, good insulation can be achieved even if the film thickness of the upper gap insulating layer 33 formed thereon is reduced to about 0.1 μm. You can keep your sex. as a result,
It is possible to provide an MR head having a higher breakdown voltage while having a better resolution. Further, by thus flattening, the shapes of the lower magnetic layer 46 and the upper magnetic layer 49, which form the core of the inductive head formed on the MR head, have a good flat shape without distortion. An inductive head with good efficiency can be obtained.

As the flattening technique, various known methods other than the above-mentioned etch back method can be applied.

[0037]

As described above in detail, according to the present invention, after the leads are formed on the insulator and the MR film, the upper surfaces of the leads and the insulator are flattened, and the flattened upper surfaces are formed. Since the upper gap insulating layer is formed on
The upper gap insulating layer becomes flat, and the insulating property is sufficiently maintained even if the film thickness is reduced. Further, the shape of the magnetic layer (core) of the inductive head formed thereabove is free from distortion, and the writing efficiency is improved. As a result, it is possible to obtain a thin film magnetic head having a high breakdown voltage and an excellent resolution and an excellent writing characteristic.

[Brief description of drawings]

FIG. 1 is a bottom view schematically showing a partial configuration of a thin film magnetic head in the embodiment of FIG. 2 from the bottom side facing a magnetic medium.

FIG. 2 is a perspective view showing a flying type magnetic head unit including a composite type thin film magnetic head as one embodiment of the present invention.

FIG. 3 is a partial cross-sectional view taken along the line AA of FIG.

FIG. 4 is a diagram showing a part of the manufacturing process of the thin film magnetic head in the embodiment of FIG.

FIG. 5 is a bottom view schematically showing a part of the configuration of the conventional thin film magnetic head from the bottom side facing the magnetic medium.

[Explanation of symbols]

 23 ceramic structure 26, 26 'lead 30 lower shield layer 31 MR film 32 lower gap insulating layer 33 upper gap insulating layer 34, 34' insulator 35 upper shield layer 46 lower magnetic layer 49 upper magnetic layer

Claims (5)

[Claims] 1. A thin film magnetic in which a lower gap insulating layer, a magnetoresistive film, a protective insulator for the magnetoresistive film, a lead, and an upper gap insulating layer are sequentially laminated between a lower shield layer and an upper shield layer. A thin-film magnetic head, wherein the head is flattened so that the upper surface of the protective insulator and the upper surface of the lead are substantially in the same plane. 2. The inductive head is laminated on the upper shield layer.
The thin film magnetic head described in 1. 3. A magnetoresistive film is formed on a lower shield layer via a lower gap insulating layer, and an insulator for protecting the magnetoresistive film from etching is formed on a predetermined portion of the magnetoresistive film. A lead is formed on the body and the magnetoresistive film, the upper surfaces of the lead and the insulator are flattened, and an upper shield layer is formed on the flattened upper surface via an upper gap insulating layer. And a method for manufacturing a thin film magnetic head. 4. The method of manufacturing a thin film magnetic head according to claim 3, wherein the flattening is performed by an etch back method. 5. The inductive head is laminated on the upper shield layer.
7. A method of manufacturing a thin film magnetic head according to.