JP2000067419A - Thin-film magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To flatly form an antiferromagnetic film even if the surface roughness of a lower insulating layer is large when this antiferromagnetic film is formed on the lower insulating layer. SOLUTION: Another insulating layer 21a is formed on the lower insulating layer 11 and the antiferromagnetic film 13 is formed on this insulating layer 21a. As a result, the antiferromagnetic film 13 can be made flat even if the surface roughness of the lower insulating layer 11 is large. The increasing of the isolation voltage between the antiferromagnetic film 13 and the lower insulating layer 11 is possible as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head using a thin film element used as a floating magnetic head, for example.

[0002]

2. Description of the Related Art FIG. 3 shows a floating magnetic head H for a hard disk drive as an example of a magnetic head using a thin film element.

[0003] The slider 1 of the magnetic head H has (a)
Is a leading side facing upstream in the moving direction of the disk surface, and (b) is a trailing side. On the surface of the slider 1 facing the disk, rail-like ABS surfaces 1a, 1
a, 1b and an air groove 1c between the ABSs. The thin film element 2 is provided on an end face 1d of the slider 1 on the trailing side.

FIG. 4 is an enlarged view of a cross section taken along line IV-IV of FIG.

The thin-film element 2 has a reproducing head layer 10 including a magnetoresistive element (MR element) between a lower shield layer 3 such as plated permalloy and an upper shield layer 4. An upper core layer 5 is formed on the surface of the upper shield layer 4, and a coil layer 6 spirally formed in a plane around the connection portion 5 a between the upper shield layer 4 and the upper core layer 5 is provided. Then, the upper core layer 5 and the coil layer 6 are covered with a protective film 7. The upper shield layer 4 functions as a core, and an opposing portion between the upper shield layer 4 and the upper core layer 5 appears on the ABS 1b to form a magnetic gap G of the inductive recording head.

FIG. 5 shows the structure of the read head layer 10 formed between the lower shield layer 3 and the upper shield layer 4, and is an enlarged front view as seen from the direction of arrow V in FIG. is there.

As shown in FIG. 5, in the reproducing head layer 10, a lower insulating layer 11 of alumina (Al ₂ O ₃ ), which is a non-magnetic material, is formed on the surface of the lower shield layer 3; , A magnetoresistive element (MR element) 12 is laminated. As a configuration example of the MR element 12, a SAL film 12a, a SHUNT film 12b of a non-magnetic material,
This is a three-layer structure of the MR film 12c having a magnetoresistance effect.

Both sides of the surface of the MR element 12 are covered with antiferromagnetic films (antiferromagnetic films) 13 and 13 (FeMn), and the surface thereof is further covered with conductive films 14 and 14 mainly composed of, for example, tungsten (W). Covered. Further, the surfaces of the conductive films 14 and 14 are covered with an upper insulating layer 15 of alumina or the like, and the upper portion is the upper shield layer 4.

In the reproducing head layer 10, the MR film 12c
And the distance between the lower shield layer 3 and the upper shield layer 4 determine the gap length (Gl). In addition, the track width Tw is equal to 1
4 is determined by the range in which the sense current flows.

[0010]

The read head layer 10 having the above structure has the following problems.

Conventional lower insulating layer 11 and upper insulating layer 15
Both have a single-layer structure in which an inorganic insulating material such as alumina (Al ₂ O ₃ ) is sputtered. This inorganic insulating material such as alumina is likely to form pinholes during the film formation process. Further, in the case of a sputtering layer of an inorganic insulating material, it is difficult to smooth the steps of the layer below the inorganic insulating material. Therefore, in the case of the lower insulating layer 11, if the surface roughness of the lower shield layer 3 is large, 11 also has a large surface roughness. As a result, the antiferromagnetic films 13 may not be formed smoothly.

When the antiferromagnetic films 13 and 13 function as a part of the electrode layer, the lower insulating layer 11 provides a sufficient insulating function between the lower shield layer 3 and the antiferromagnetic film 13. Can not be demonstrated.

Further, in the reproducing head layer 10 shown in FIG.
Although this is set at an interval of 3, the accuracy of the track width Tw is limited because this interval is formed by cutting the antiferromagnetic film 13 by milling or the like.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has an object to improve the flattening of an underlayer of an antiferromagnetic film, an improvement in electric breakdown voltage when the antiferromagnetic film is used as an electrode, and It is an object of the present invention to provide a thin-film magnetic head whose width can be determined with high precision.

[0015]

According to the present invention, there is provided a thin film magnetic head comprising: a lower insulating layer formed on a lower shield layer; and a laminated body having a magnetoresistive effect formed on the lower insulating layer. And an antiferromagnetic film superimposed on the laminate, wherein an insulating layer different from the lower insulating layer is interposed between the antiferromagnetic film and the lower insulating layer. It is.

Further, the antiferromagnetic film may be formed from above the stacked body to above the lower insulating layer, and the antiferromagnetic film may function as an electrode layer.

Further, the thin-film magnetic head of the present invention comprises: a lower insulating layer formed on a lower shield layer; a laminated body formed on the lower insulating layer and exhibiting a magnetoresistive effect; An antiferromagnetic film to be superimposed, a track width regulating insulating layer for determining a track width is provided on the laminate, and the antiferromagnetic film contacts the laminate on both sides of the track width regulating insulating layer. In addition, it is formed in a region overlapping the track width regulating insulating layer.

Also in this case, the antiferromagnetic film is formed at an interval in the track width direction so as to overlap the track width regulating insulating layer, and the antiferromagnetic film can function as an electrode layer.

Further, the antiferromagnetic film is laminated on the lower insulating layer with another insulating layer interposed therebetween, and the other insulating layer and the track width regulating insulating layer are formed of the same insulating material. It is possible.

Further, the other insulating layer and the track width regulating insulating layer are continuous, and the other insulating layer and the track width regulating insulating layer are separated on the laminate. Can be.

[0021]

According to the first aspect of the present invention, even if the surface roughness of the lower shield layer is large, and as a result the roughness of the lower insulating layer becomes large, another surface is formed between the lower insulating layer and the antiferromagnetic film. By interposing the insulating layer, the flatness of the antiferromagnetic film can be increased. In the case where an antiferromagnetic film is used as an electrode layer, even if a pinhole is generated in the lower insulating layer, the provision of the other insulating layer can increase the electrical withstand voltage.

According to the third aspect of the present invention, when the track width is determined by the antiferromagnetic film, a thin track width regulating insulating layer is formed on the laminated body exhibiting the magnetoresistive effect, By determining the dimensions, the track width can be formed with high precision.

Further, the track width regulating insulating layer and another insulating layer interposed between the antiferromagnetic film and the lower insulating layer are formed of the same insulating material, so that both insulating layers are separated by etching. The track width can be determined with high accuracy by this etching.

[0024]

Embodiments of the present invention will be described below.

FIG. 1 shows the configuration of a thin-film magnetic head according to an embodiment of the present invention. This thin film magnetic head is
For example, the thin film element 2 of the floating magnetic head shown in FIGS.
1 is used as a reproducing head layer 10 of FIG.
FIG. 3 is an enlarged front view of the flying magnetic head as viewed from the ABS 1b side. FIG. 2 is a sectional view taken along line II-II of FIG.

On the trailing end face 1 d of the slider 1, a lower shield layer 3 of, for example, plated permalloy (NiFe) and a lower insulating layer 11 are laminated. The lower insulating layer 11 is formed by sputtering alumina (Al ₂ O ₃ ). On this lower insulating layer 11, a magnetoresistive element (MR element) 12 is laminated. The MR element 12 has a three-layer structure, and includes a SAL film 12a, a SHUNT film 12b of a non-magnetic material,
This is the R film 12c.

In the embodiment shown in FIG. 1, another insulating layer 2 extends from the upper surface of the left and right edges of the MR element 12 to the surface of the lower insulating layer 11.
On the center surface of the MR element 12, a band-shaped insulating layer 2 having a width dimension Tw, which is a track width regulating insulating layer, is formed.
1b is formed. As shown in FIG.
a and the insulating layer 21b are continuous with the same film, and grooves 22 and 22 are formed on the surface of the MR element 12. As a result, as shown in FIG.
b appears in a separated state.

The insulating layers 21a and 21b are made of the MR element 1
2 and the lower insulating layer 11 are formed by sputtering a thin film of Si ₃ N ₄ and then etching the grooves 22 and 22.

The material of the insulating layers 21a and 21b is S
i ₃ N ₄ other Si-N-based material or,, Si-O system, S
i-O-N-based materials, such as Ta ₂ O ₃ can be used.
In the case of a material that can be etched, the grooves 22, 22 are formed by etching, and in the case of a material that requires milling, the grooves 22, 22 are formed by ion milling or the like. In the case of lift-off, groove 2
The insulating layers 21a and 21b can be formed by masking portions corresponding to portions 2 and 22 with a resist and forming a film.

The electrode layers 23 are formed on the insulating layers 21a and 21b. The electrode layers 23, 23
The lower layer is an antiferromagnetic film (antiferromagnetic film) 13 having a NiFe / FeMn configuration, and the upper layer is a conductive film 14 having a Ta / Cu / Ta configuration. The electrode layers 23, 23
1a to the surface of the MR element 12 and the insulating layer 21
b is formed over both edges of the upper surface. This electrode layer 2
3 and 23 are electrically connected to the outermost MR film 12c of the MR element 12 in the grooves 22 and 22. And the insulating layer 21
The track width is determined by the width Tw of b.

In the above embodiment, the antiferromagnetic film 13 is formed as a lower layer over the entire area of the electrode layer 23. However, the antiferromagnetic film 13 is formed only at a portion in contact with the MR element 12,
In other portions, the conductive film 14 of the electrode layer 23 may be in contact with the insulating layer 21a.

In the above embodiment, the lower insulating layer 3 and the insulating layer 21a have a double insulating structure between the lower shield layer 3 and the electrode layer 23 (the antiferromagnetic film 13). The electrode layers 23 and 23 including the ferromagnetic film can be flattened, and the insulating property can be improved. The insulating layer 21a can be formed simultaneously with the insulating layer 21b that determines the track width, and can be formed by separating the insulating layers 21a and 21b on the MR element 12 by etching or the like. There is no need to provide a separate step.

In the above embodiment, a thin-film magnetic head used together with an inductive recording head in the floating magnetic head as shown in FIG. 3 is assumed. The present invention is not limited to magnetic heads, but can be implemented as various magnetic heads.

[0034]

As described above, according to the present invention, the antiferromagnetic film can be formed flat, and the withstand voltage between the antiferromagnetic film and the lower insulating layer can be improved.

Further, the track width can be formed with high precision, and the insulating layer for determining the track width and the insulating layer formed on the lower insulating layer can be formed by simple steps.

[Brief description of the drawings]

FIG. 1 is an enlarged front view showing a thin-film magnetic head according to a first embodiment of the present invention;

2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a perspective view showing a floating magnetic head as an example of using the thin film magnetic head;

FIG. 4 is an enlarged view of a cross section taken along line IV-IV of FIG. 3;

FIG. 5 is an enlarged front view taken along the arrow V in FIG.

[Explanation of symbols]

 Reference Signs List 1 slider 1b ABS surface 1d trailing side end surface 2 thin film element 3, 4 shield layer 10 reproducing head layer 11 lower insulating layer 12 MR element 12a SAL film 12b SHUNT film 12c MR film, 13 antiferromagnetic film 14 conductive film 15 upper part Insulating layer 21a Other insulating layer 21b Insulating layer that determines track width Tw 23 Electrode layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideyuki Hashimoto 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd. (72) Inventor Naoishi Ishibashi 1-7 Yukitani-Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd. (72) Inventor Minoru Yamada 1-7 Yukitani Otsuka-cho, Ota-ku, Tokyo Alps Electric Co., Ltd.

Claims (6)

[Claims] 1. A lower insulating layer formed on a lower shield layer, a laminated body having a magnetoresistive effect formed on the lower insulating layer, and an antiferromagnetic film laminated on the laminated body. A thin-film magnetic head comprising: an insulating layer different from the lower insulating layer between the antiferromagnetic film and the lower insulating layer. 2. The thin-film magnetic head according to claim 1, wherein the antiferromagnetic film is formed from above the stacked body to above the lower insulating layer, and the antiferromagnetic film functions as an electrode layer. 3. A lower insulating layer formed on a lower shield layer, a laminated body formed on the lower insulating layer and exhibiting a magnetoresistive effect, and an antiferromagnetic film laminated on the laminated body. A track width regulating insulating layer for determining a track width is provided on the laminate, and the antiferromagnetic film is in contact with the laminate on both sides of the track width regulating insulating layer and the track width regulating insulating layer A thin-film magnetic head formed in a region overlapping with the thin-film magnetic head. 4. The thin film according to claim 3, wherein the antiferromagnetic film is formed at intervals in the track width direction so as to overlap the track width regulating insulating layer, and the antiferromagnetic film functions as an electrode layer. Magnetic head. 5. The antiferromagnetic film is stacked on the lower insulating layer with another insulating layer interposed therebetween, and the other insulating layer and the track width regulating insulating layer are formed of the same insulating material. Item 5. The thin film magnetic head according to item 3 or 4. 6. The another insulating layer and the track width regulating insulating layer are continuous, and the other insulating layer and the track width regulating insulating layer are separated on the laminated body.
The thin-film magnetic head as described in the above.