JP3378458B2 - Thin film magnetic head and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thin film magnetic head and a method for manufacturing the same.

[0002]

^2. Description of the Related Art In recent years, magnetic recording density has been increased, and HDDs have been put to practical use with a high recording density system of 1 Gbpsi / inch ² , and further higher recording density is required. There is. In order to achieve such high density of magnetic recording, it is an essential technical subject to narrow the track width of the thin film magnetic head and to increase the accuracy of the track width tolerance.

In the case of the above 1 Gbps i / inch ² HDD,
The track width is required to be about 2 μm and the track-to-track distance is required to be about 0.5 μm, and further narrower tracks and higher precision are required to meet higher recording density. For example, if the recording density becomes 10 Gbpsi / inch ² in the future, the track width will be 1 μm or less and the track width tolerance will be 0.1 μm.
It is expected that about m will be required. In addition, it is expected that the recording current will be reduced as the recording frequency becomes higher, and a head constituent material having high saturation magnetic flux density and high resistance will be required. In order to meet these requirements, it is necessary to greatly improve the magnetic head.

For example, a thin film magnetic head having a trench pole structure has been proposed as one of the measures for narrowing the track. In the trench pole structure, the tip of the recording magnetic pole of the magnetic head, that is, the tip of the magnetic pole located on the medium facing surface is formed by embedding the magnetic layer in a trench formed in an insulating layer or the like. According to such a magnetic pole structure, the shape and formation position of the magnetic pole tip can be controlled by the shape of the trench and the like, so that the recording pole tip with a narrowed track can be realized with high accuracy.

The thin film magnetic head having the trench pole structure as described above is manufactured, for example, as follows. That is, first, a lower magnetic pole is formed of a soft magnetic material such as a NiFe alloy, and an amorphous Si is formed on the lower magnetic pole as a magnetic gap.
Non-magnetic film such as Si and Si as an insulating layer for trench formation
An O _x layer or the like is formed. Next, a trench is formed by RIE or the like on the medium facing surface side of the trench forming insulating layer. Further, a magnetic field generating coil is formed on the rear side, and the coil is covered with an insulating material such as resist. Then, a soft magnetic material such as an amorphous CoZrNb alloy is embedded in the trench to form a magnetic pole tip of the upper magnetic pole, and an upper magnetic pole body made of the same soft magnetic material is formed on the rear side thereof. By covering the surface of the upper magnetic pole with an insulating protective film, a thin film magnetic head having a trench pole structure is completed.

By the way, in the above-mentioned conventional thin film magnetic head having the trench pole structure, the coil is covered with an organic insulating material such as a resist in order to electrically cut off the magnetic pole from the coil. The distance between the magnetic pole tip portion of the magnetic pole and the magnetic pole body and the coil cannot be reduced very much. Therefore, in order to generate the magnetic field required for the recording operation in the upper magnetic pole, it is necessary to apply a large current to the coil, which causes a problem that the coil is likely to be broken. Further, in order to prevent a disconnection and the like and to apply a large current to the coil, it is necessary to increase the sectional area of the coil. On the other hand, in order to provide the coil close to the tip of the magnetic pole, it is necessary to improve the alignment accuracy of the coil. However, in the conventional head structure that uses resist or the like for insulating the coil, such alignment accuracy is increased. Is extremely difficult to satisfy.

Further, since the coil is covered with an organic insulating material such as a resist, the surface of the base portion on which the upper magnetic pole is formed is likely to be uneven, reflecting the unevenness of the coil. In the upper magnetic pole formed on the portion having such unevenness, the portion reflecting the unevenness of the base becomes the pinning site of the domain wall, and it is difficult to form a single magnetic domain. A magnetic pole having many domain walls deteriorates head characteristics, especially high frequency response characteristics. In addition, organic insulating materials such as resists are vulnerable to heat applied when the resist is hardened in the head processing process, heat generated by applying current to the coil, etc., and reduce the reliability of the magnetic head. There is.

[0008]

As described above, in the conventional thin film magnetic head, the resist or the like is used to insulate the coil, so that the coil forming position accuracy cannot be sufficiently improved, and therefore, There is no choice but to form the upper magnetic pole tip portion and the coil adjacent thereto sufficiently apart. Therefore, there is a problem that the coil current for generating the magnetic field necessary for the recording operation becomes large. Furthermore, when the upper magnetic pole is formed, the unevenness of the lower ground is large, and that portion becomes the pinning site of the domain wall, which makes it difficult to form a single magnetic domain.

The present invention has been made to address such a problem, and by improving the accuracy of the coil forming position, it is possible to form the magnetic pole tip of the upper magnetic pole closer to the coil. In addition, it is an object of the present invention to provide a thin-film magnetic head capable of smoothing the lower ground of the upper magnetic pole and a method for manufacturing the same.

[0010]

A thin-film magnetic head according to the present invention has a lower magnetic pole and an upper magnetic pole formed on the lower magnetic pole via a magnetic gap. ,
In a thin film magnetic head comprising a coil provided between the lower magnetic pole and the upper magnetic pole, the lower magnetic pole has a plurality of surfaces aligned with the coil forming position on a surface facing the coil. It is characterized by having a convex portion.

The thin-film magnetic head of the present invention is further characterized in that the coils are electrically separated by an insulating layer formed between the convex portions adjacent to each other. I am trying. Further, in the thin film magnetic head of the present invention, as described in claim 3, the magnetic gap is formed between at least one of the lower magnetic pole and the upper magnetic pole and the coil. It is characterized in that a magnetic insulating layer is formed.

[0012]

In the thin film magnetic head of the present invention, as described in claim 4, a part of the convex portion is aligned with the formation position of the magnetic pole tip portion of the upper magnetic pole. According to a fifth aspect of the present invention, there is provided a method of manufacturing a thin-film magnetic head, wherein a step of forming an upper magnetic pole on the lower magnetic pole via a magnetic gap, and a coil between the lower magnetic pole and the upper magnetic pole. A method of manufacturing a thin film magnetic head, comprising: a step of forming a plurality of convex portions on a surface of the lower magnetic pole; and a surface having a surface reflecting the shape of the convex portion on the lower magnetic pole. forming an insulating layer, the second
A recess formed between the plurality of protrusions on the surface of the first insulating layer
A step by forming an insulating layer to form forming a recess aligned with the protrusion, the step of forming the coil in the recess, forming a second insulating layer covering the coil, the second And a step of forming the upper magnetic pole on the insulating layer.

[0014]

In the thin film magnetic head of the present invention , since the coil forming position is defined by the convex portion provided on the surface of the lower magnetic pole, the coil forming position accuracy can be improved. Therefore, the coil can be accurately formed at a position sufficiently close to the tip of the upper magnetic pole.

Further, by increasing the positional accuracy of the coil, it becomes possible to perform insulation between the coil and, for example, the upper magnetic pole by the nonmagnetic insulating layer forming the magnetic gap. Therefore, the distance between the upper part of the coil and the upper magnetic pole can be sufficiently short, and the surface smoothness of the lower ground of the upper magnetic pole can be improved. By smoothing the underlying surface of the upper magnetic pole, pinning sites of the domain wall are reduced, so that the upper magnetic pole can be easily made into a single domain during head operation. Therefore, the recording noise accompanying the domain wall movement can be significantly reduced .

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments for carrying out the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cutaway view showing a schematic structure of a recording / reproducing integrated magnetic head of an embodiment to which a thin film magnetic head of the present invention is applied as a recording head portion.

[0019] In the figure, 11 is a substrate such as Al ₂ O ₃ · TiC substrate having the Al ₂ O ₃ layer. This board 1
A lower magnetic shield layer 12 made of a NiFe alloy, an amorphous CoZrNb alloy, or the like is formed on the first layer 1. A magnetoresistive effect element (MR element) 14 is formed as a reproducing element section on the lower magnetic shield layer 12 via a lower reproducing magnetic gap 13 made of a nonmagnetic insulating material such as AlO _x . In the figure, reference numeral 15 is a lead (electrode) for supplying a sense current to the MR film.

An upper magnetic shield layer 17 is formed on the MR element 14 including the leads 15 via an upper reproducing magnetic gap 16 made of a non-magnetic insulating material similar to the lower reproducing magnetic gap 13. These constitute a shield type MR head 18 as a reproducing head section.

On the above-mentioned shield type MR head 18, a thin film magnetic head 19 is formed as a recording head portion. The lower recording magnetic pole of the thin film magnetic head 19 is composed of the same magnetic layer as the upper magnetic shield layer 17. That is, the upper magnetic shield layer 17 of the shield type MR head 18 also serves as the lower recording magnetic pole of the thin film magnetic head 19. The upper magnetic shield layer (hereinafter abbreviated as the lower recording magnetic pole) 17 also serving as the lower recording magnetic pole 17 is made of a crystalline soft magnetic material such as NiFe alloy or FeSiAl alloy, (Fe, Co) N-based material, ( A fine crystalline soft magnetic material such as Fe, Co) O system or an amorphous soft magnetic material such as CoZrNb alloy is used.

As shown in FIGS. 2 and 3, the lower recording magnetic pole 17 has a magnetic pole tip 17a facing the medium facing surface and a coil forming position which are convex. That is, the lower recording magnetic pole 17 is the magnetic pole tip portion 2 of the upper recording magnetic pole 25 described later.
5a and a surface facing the coil 24 are provided with a plurality of convex portions 20 that are aligned with the formation position of the upper recording magnetic pole tip portion 25a and the formation position of the coil 24. The convex portion 20a aligned with the formation position of the upper recording magnetic pole tip portion 25a referred to here.
Corresponds to the magnetic pole tip portion 17a of the lower recording magnetic pole 17 having a width corresponding to the recording track width. In the figure, 20b is a convex portion that matches the formation position of the coil 24, and is formed along the formation shape of the coil 24. Here, FIG. 2 is a longitudinal sectional view of a main part of the thin film magnetic head 19, and FIG. 3 is a sectional view as seen from the medium facing surface.

On the lower recording magnetic pole 17 having the convex portion 20 as described above, along the shape of the convex portion 20, a first layer made of amorphous Si (a-Si), AlO _x , SiN _x or the like is formed. The nonmagnetic insulating material layer 21a is used as the recording magnetic gap 2
It is formed as a part of 1. On the first non-magnetic insulating material layer 21a, a recess forming insulating layer 22 made of a non-magnetic insulating material different from the recording magnetic gap 21, for example, SiO _x is formed.

The recess forming insulating layer 22 is formed on the upper recording magnetic pole 2.
5 has a concave portion 23 which is aligned with the convex portion 20 corresponding to the formation position of the magnetic pole tip portion 25a and the coil formation position and which has the bottom surface of the first nonmagnetic insulating material layer 21a. That is, the recess forming insulating layer 22 has the first recess 23a aligned with the protruding portion 20a corresponding to the formation position of the upper recording magnetic pole tip portion 25a, and the protruding portion 20b corresponding to the formation position of the coil 24. And a groove-shaped second concave portion 23b aligned with respect to .

The coil 2 made of Cu, Cu alloy or the like is placed in the second recess 23b aligned with the protrusion 20b.
4 is embedded. That is, the coil 24 is
It is electrically separated by the insulating layer 22 for forming the concave portion formed between the convex portions 20b adjacent to each other. Then, the second non-magnetic insulating material layer 21b, which is a part of the recording magnetic gap 21, is formed on the recess forming insulating layer 22 including the coil 24 embedded in the second recess 23b. Has been done. The second nonmagnetic insulating material layer 21b is made of a material similar to that of the first nonmagnetic insulating material layer 21a. That is, the coil 24 is embedded in the second recess 23b, and the periphery thereof is surrounded by the first nonmagnetic insulating material layer 21a, the recess forming insulating layer 22 and the second nonmagnetic insulating material layer 21.
It is insulated by b.

Since the second non-magnetic insulating material layer 21b becomes a part of the recording magnetic gap 21, the medium facing surface side has the first concave portion 2 corresponding to the formation position of the upper recording magnetic pole tip portion 25a.
It is formed along the inner wall surface of 3a. That is, the portion that actually functions as the recording magnetic gap 21 located on the medium facing surface is the first and second nonmagnetic insulating material layers 21.
It is composed of a laminated film of a and 21b.

As described above, the second nonmagnetic insulating material layer 21 is formed.
b is formed along the inner wall surface, and the portion that actually functions as the recording magnetic gap 21 is formed of a laminated film of first and second nonmagnetic insulating material layers 21a and 21b.
In the recess 23a, a magnetic material forming the upper recording magnetic pole 25, for example, a soft magnetic material similar to that of the lower recording magnetic pole 17 is embedded. The soft magnetic material embedded in the first recess 23 a forms the magnetic pole tip portion 25 a of the upper recording magnetic pole 25.

Since the convex portion 20a and the first concave portion 23a are aligned with each other, the magnetic pole tip portion 17a of the lower recording magnetic pole 17 and the magnetic pole tip portion 25 of the upper recording magnetic pole 25 are arranged.
The a is formed so as to be opposed to the medium facing surface via the recording magnetic gap 21 and to be aligned with high precision so that the respective center positions overlap. The width of the surface facing the recording magnetic gap 21 is also set to be substantially the same. Also, the upper recording magnetic pole tip portion 25a
Indicates the coil 2 based on the formation position of each convex portion 20a, 20b.
4 is aligned.

The upper recording magnetic pole 25 has a magnetic pole tip portion 25a.
From the rear side of the medium facing surface, and the end on the rear side is connected to the lower recording magnetic pole 17. As described above, the lower recording magnetic pole 17 and the upper recording magnetic pole 25 form one magnetic circuit via the recording magnetic gap 21, and the coil 24 includes the lower recording magnetic pole 17 and the upper recording magnetic pole in the magnetic circuit. The magnetic pole 25 is arranged in an insulated state. These components constitute a main part of the thin film magnetic head 19 as a recording head unit.

Incidentally, FIG. 1 shows a state in which the upper recording magnetic pole 25 is collectively formed. The upper recording magnetic pole in the present invention is not limited to this, and may be, for example, the first concave portion 23a.
A separated magnetic pole may be formed by a magnetic pole tip half body embedded in the inside and a magnetic pole rear half body that makes surface contact with the magnetic pole tip half body and extends to the rear side.

In the thin film magnetic head 19 described above,
Since the convex portion 20 is provided on the lower recording magnetic pole 17 and the convex portion 20 defines the formation position of the upper recording magnetic pole tip portion 25a and the formation position of the coil 24, the formation position accuracy of these can be improved. Particularly, by embedding the upper recording magnetic pole tip 25a and the coil 24 in the recess 23 aligned with the protrusion 20, the track width of the upper magnetic pole tip 25a can be accurately narrowed. The positional accuracy of the coil 24 with respect to the upper recording magnetic pole tip portion 25a can be significantly improved.

Therefore, the coil 24 can be accurately formed at a position sufficiently close to the tip end portion 25a of the upper recording magnetic pole. Further, by increasing the positional accuracy of the coil 24, the upper part of the coil 24 and the upper recording magnetic pole 2
5 can be insulated from each other by the second non-magnetic insulating material layer 21b which is a part of the recording magnetic gap 21, so that the distance between the upper portion of the coil 24 and the upper recording magnetic pole 25 is sufficient. Can approach.

Specifically, as shown in FIG. 4, the distance T from the upper recording magnetic pole tip portion 25a to the adjacent coil 24 is T.
₁ can be 10 μm or less. Also, the coil 24
The distance T ₂ between the upper part of the magnetic recording medium and the upper recording magnetic pole 25, that is, the film thickness of the second nonmagnetic insulating material layer 21b can be 0.5 μm or less. Lower part of coil 24 and lower recording magnetic pole 1
The distance T ₃ with 7 can be similar. on the other hand,
Figure 5 As shown in the 'in the conventional thin film magnetic head which has been insulated with a resist R and the like, the upper recording magnetic pole tip 25a' coil 24 a distance t ₁ to the coil 24 'to close from 10μm or more, the coil The distance t ₂ between the upper part of 24 ′ and the upper recording magnetic pole 25 ′ is about 3 μm.

By setting the distance from the upper recording magnetic pole tip portion 25 to the adjacent coil 24 to 10 μm or less and the distance from the upper part of the coil 24 to the upper recording magnetic pole 25 to 0.5 μm or less, the current flowing through the coil 24 is After reducing the magnetic field, a sufficient magnetic field necessary for the recording operation is applied to the lower recording magnetic pole 17
Can be applied to the magnetic circuit by the upper recording magnetic pole 25. This corresponds to the current situation where the recording current is required to be reduced as the recording frequency becomes higher. If the distance from the upper recording magnetic pole tip 25 to the adjacent coil 24 exceeds 10 μm, it is necessary to apply a large current to the coil in order to generate the magnetic field required for the recording operation.
Therefore, it becomes necessary to increase the cross-sectional area of the coil.

However, if the distance between the upper recording magnetic pole tip portion 25a and the coil 24 is less than 0.1 μm, the insulation between them may not be stably ensured. The distance to the coil 24 is preferably 0.1 μm or more. This distance is
The range of 0.1 to 7 μm is more preferable. The distance from the upper part of the coil 24 to the upper recording magnetic pole 25, that is, the film thickness of the second nonmagnetic insulating material layer 21b is also preferably 0.05 μm or more for the same reason. The thickness of the second non-magnetic insulating material layer 21b is preferably 0.5 μm or less in order to suppress the occurrence of irregularities on the surface.

Further, by forming the second non-magnetic insulating material layer 21b between the upper part of the coil 24 and the upper recording magnetic pole 25, the unevenness of the underlying surface of the upper recording magnetic pole 25 becomes small, so that the pinning of the domain wall is achieved. Fewer sites.
Therefore, the upper recording magnetic pole 25 can be easily made into a single magnetic domain during the head operation, and the recording noise due to the domain wall movement can be significantly reduced. For this reason, it is preferable that the underlying surface of the upper recording magnetic pole 25, that is, the surface unevenness of the second nonmagnetic insulating material layer 21b is 0.5 μm or less. It is more preferably 0.3 μm or less. In addition, around the coil 24, a-Si, AlO _x , SiN _x , SiO
_Since it is insulated with an inorganic material such as _x , the heat resistance temperature thereof can be dramatically improved as compared with the case where an organic insulating material such as a conventional resist is used.

Further, since the second non-magnetic insulating material layer 21b is formed in the recess 23a for embedding in the upper recording magnetic pole tip 25a, the surface of the bottom surface and side wall surface of the recess is slightly roughened when the recess is formed. Even in this case, the surface property is improved by the second non-magnetic insulating material layer 21b, and the magnetic characteristics can be improved. In addition, the second non-magnetic insulating material layer 2
By adjusting the film thickness of 1b, the track width and the magnetic gap width can be easily controlled.

Next, the manufacturing process of the thin film magnetic head 19 as the recording head portion of the recording / reproducing integrated magnetic head of the above-described embodiment will be described with reference to FIGS. 6 and 7.

First, the film thickness of about 2 is formed on the substrate on which the upper reproducing magnetic gap 16 of the shield type MR head 18 is formed.
A soft magnetic film of about μm is used as the lower recording magnetic pole 17 for RF (Rad
ioFrequancy) formed by a sputtering method or the like. As the soft magnetic film, an amorphous alloy film such as Co ₈₇ Zr ₅ Nb ₈ (at%),
Nitrogenated microcrystal film and oxide microcrystal film of (Fe, Co) type alloy, Ni ₈₀ Fe ₂₀ (at%) and FeAlSi (sendust)
A crystalline film or the like is used. The lower recording magnetic pole 17 can also be formed by laminating a plurality of these soft magnetic materials. With such a structure, the magnetic flux from the upper recording magnetic pole 25 is efficiently transmitted to the lower recording magnetic pole 17.

Next, as shown in FIG. 6A, a photoresist film is applied on the lower recording magnetic pole 17 which is flattened by, for example, etch back or polishing, and a resist pattern 26 is formed by a PEP process. The resist pattern 26 is formed according to the formation position of the upper recording magnetic pole tip portion 25a and the formation position of the coil 24.

Using the resist pattern 26 as a mask, the lower recording magnetic pole 17 is etched by an ion milling method or the like to form, for example, a width of 1 μm, a depth of 5 μm, and a height at a portion corresponding to the formation position of the upper recording magnetic pole tip portion 25a.
A continuous protrusion 20b having, for example, a width of 5 μm and a height of 0.5 μm is formed on the protrusion 20a of 0.5 μm and the portion corresponding to the position where the coil 24 is formed. After that, the resist pattern 26 is removed to form an uneven shape as shown in FIG. 6B on the surface of the lower recording magnetic pole 17.

Next, as shown in FIG. 6C, for example, a film thickness of 0.1 μm is formed on the uneven surface of the lower recording magnetic pole 17.
First non-magnetic insulating material layer 21 made of a-Si film or the like
a is formed by the RF sputtering method or the like. The non-magnetic insulating material layer 21a having such a thickness can be formed along the shape of the convex portion 20, in other words, by reflecting the shape of the convex portion 20 by a normal sputtering method or the like. Then the film thickness 1.5
Insulation layer 22 for forming recesses made of SiO _x film of about μm
Are formed by a biased RF sputtering method or the like.

In forming the recess forming insulating layer 22 described above, the film forming conditions and the like are reflected so that the shape of the protruding portion 20 is reflected and the insulating layer 22 is formed with a substantially uniform thickness along the shape of the protruding portion 20. Control. Thereby, the convex insulating layer 22 in which the shape of the convex portion 20 is transferred is obtained. A non-magnetic film such as a Ti film may be interposed at the interface between the recess forming insulating layer 22 and the lower recording magnetic pole 17 for the purpose of improving the adhesiveness.

Then, as shown in FIG. 6C, a resin layer 27 having a flattening effect is formed on the insulating layer 22 for forming a concave portion formed along the shape of the convex portion 20 described above. The surface of the resin layer 27 is flattened. As the resin layer 27 having this flattening effect, for example, a low molecular weight resin such as novolac resin is used. Low molecular weight resin is fluidized by heating at about 473K,
By applying heat treatment after coating, the surface can be flattened.

Here, the surface-flattened resin layer 27 is
Since the resin layer 27 is thin just above the convex portion 20 and thick in other portions, the resin layer 27 is anisotropically etched by RIE (Reactive Ion Etching) or the like using the resin layer 27 as a mask material. The thick portion can be a substantial mask. That is, it is possible to form a mask layer that shares the same plane as the portion of the insulating layer 22 on the convex portion 20. The insulating layer 22 portion not covered with such a mask layer is removed by etching.

That is, as shown in FIG. 7A, the concave portion 23 is formed by selectively removing the insulating layer 22 on the convex portion 20 by etching. Specifically, the convex portion 2
0a, where the upper recording magnetic pole tip portion 25a is formed, for example, a depth of 5 μm and a depth of 1
A first recess 23a having a width of 1 μm and a width of 1 μm is formed. In addition, a groove-shaped second concave portion 23b having a depth of 1 μm and a width of 5 μm, for example, which is a portion where the coil 24 is formed, is formed in a portion aligned with the convex portion 20b. At this time, the recess 23
It does not matter if the taper surface of is somewhat rough.

As described above, the upper recording magnetic pole tip portion 25a which is aligned with the convex portions 20a and 20b is embedded based on the resin layer 27 having the convex shape and the flattening effect transferred to the concave portion forming insulating layer 22. Recess (first recess) 23a
And a recessed portion (second recessed portion) 23 for embedding the coil 24
Since b is formed at the same time, these recesses 23a, 2
Positioning accuracy of 3b is greatly improved and PEP
The number of steps can be reduced.

In the above-described etching process, the resin layer 27 having a thick periphery around the protrusion 20 is formed based on the protrusion and the surface flattening effect transferred to the insulating layer 22 for forming the recess.
Since it is carried out using a mask as a mask, it is possible to obtain the concave portion 23 aligned with the upper portion of the convex portion 20 without going through a normal alignment process. Further, except for the flattening step of the resin layer 27, it can be performed according to the usual etching and film forming steps, and in addition, the alignment step and the exposure / development step can be omitted, so that mass productivity is sufficient. It will be possible to satisfy.

Next, as shown in FIG. 7B, the coil 24 is embedded in the second recess 23b for embedding the coil. The material of the coil 24 is not particularly limited as long as it is a conductor, and the forming method thereof is a usual plating method or RF.
Sputtering method, Μ OCVD (Metal Organic CV)
Various film forming methods such as the D) method can be applied. Furthermore, the upper surfaces of the coil 24 and the recess forming insulating layer 22,
A second nonmagnetic insulating material layer 21b made of, for example, an a-Si film having a film thickness of about 0.1 μm is formed by, for example, the CVD method so as to cover the inner wall surface of the recess 23a for burying the magnetic pole tip. A recording magnetic gap 21 made of a laminated film of the first and second nonmagnetic insulating material layers 21a and 21b is formed on the bottom surface of the recess 23a for embedding the magnetic pole tip portion.

After forming the coil 24 in this way,
By forming the second non-magnetic insulating material layer 21b which is a part of the recording magnetic gap 21 at the interface between the coil 24 and the upper recording magnetic pole 25, particularly the surface of the upper portion of the coil 24 where the upper recording magnetic pole 25 is formed. The unevenness is reduced, and the upper recording magnetic pole 25 can be easily made into a single magnetic domain. Further, it is possible to suppress unevenness on the bottom surface and side wall surface of the recessed portion 23a for embedding in the upper recording magnetic pole tip portion 25a, and in addition, by narrowing the shape of the recessed portion, it becomes easier to narrow the track.

Then, as shown in FIG. 7C, the recess 23a having the second nonmagnetic insulating material layer 21b formed on the surface thereof is formed.
Co ₉₀ Z with a film thickness of about 2 μm inside and on the coil 24
The upper recording magnetic pole 25 made of an amorphous soft magnetic film such as r ₄ Nb ₆ (at%) is formed by a directional sputtering method or the like. At this time,
As a constituent material of the upper recording magnetic pole 25, a (Fe, Co) -based oxide / nitride microcrystalline film, Ni ₈₀ Fe ₂₀ (at%) or FeAl is used.
It is also possible to use a soft magnetic film having a high saturation magnetic flux density such as a crystalline film of Si (sendust) or the like. As a result, the recess 23
The height of the upper recording magnetic pole tip portion 25a formed in a is 2 μm.
m, width 0.9 μm. Therefore, the track width is 0.9 μm
Is. After that, an insulating protective film is formed by the CVD method or the like, and a plurality of thin film magnetic heads formed on the substrate are processed into a single body to complete the thin film magnetic head.

The thin-film magnetic head thus manufactured and the thin-film magnetic head manufactured by the conventional method are induced by the upper recording magnetic pole when a constant current is applied to the coil closest to the magnetic pole tip. The generated magnetic field strength is shown in FIG. 8 as the relationship between the distance between the magnetic pole tip and the coil. In the above embodiment, the distance T ₁ from the upper recording magnetic pole tip portion 25a to the adjacent coil 24 is 3 μm, and the distance T ₂ between the upper portion of the coil 24 and the upper recording magnetic pole 25 is 0.3 μm. In the thin film magnetic head manufactured by the technique, the distance t ₁ from the upper recording magnetic pole tip portion 25a ′ to the adjacent coil 24 ′ is 10 μm, and the upper portion of the coil 24 ′ and the upper recording magnetic pole 2 are
The distance t ₂ with 5'is 3 μm. As is clear from FIG. 8, the magnetic field strength induced by the conventional thin film magnetic head is only 1/10 as compared with the thin film magnetic head of the present invention, and the similar magnetic field strength is obtained by the conventional thin film magnetic head. It can be seen that the input current must be increased by 10 times in order to induce.

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

In each of the embodiments described above, the case where the thin film magnetic head of the present invention is applied to the recording head portion of the recording / reproducing integrated magnetic head has been described, but the present invention is not limited to this. It is also possible to use the thin film magnetic head of the present invention as a recording / reproducing head.

[0061]

As described above, according to the thin-film magnetic head of the present invention, the positional accuracy of the coil can be improved, so that the coil can be accurately formed at a position close to the tip of the upper magnetic pole. You can Therefore, it is possible to reduce the amount of current applied to the coil. Moreover, since the lower ground of the upper magnetic pole can be smoothed while ensuring the insulation of the coil, it is possible to improve the head characteristics.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing a schematic structure of an embodiment in which a thin film magnetic head of the present invention is applied to a recording head portion of a recording / reproducing integrated magnetic head.

FIG. 2 is a longitudinal sectional view showing a recording head portion of the recording / reproducing integrated magnetic head shown in FIG.

3 is a cross-sectional view of the recording head portion of the recording / reproducing integrated magnetic head shown in FIG. 1, as viewed from the medium facing surface.

FIG. 4 is a diagram for explaining a distance between a coil and a magnetic pole in the thin film magnetic head of the invention.

FIG. 5 is a diagram for explaining a distance between a coil and a magnetic pole in a conventional thin film magnetic head.

FIG. 6 is a cross-sectional view showing a main part of a manufacturing process of the thin-film magnetic head according to the embodiment of the present invention.

7 is a cross-sectional view showing a manufacturing process of the thin-film magnetic head following the manufacturing process of FIG.

FIG. 8 is a diagram showing a relationship between a coil-upper magnetic pole distance and a magnetic field strength of a thin-film magnetic head according to an embodiment of the present invention in comparison with a conventional thin-film magnetic head .

[Explanation of symbols]

17 ... Lower recording magnetic pole 17a ... Tip of lower recording magnetic pole 20 ... Convex part 21 ... Recording magnetic gap 21a ... First non-magnetic insulating material layer 21b ... second non-magnetic insulating material layer 22 ... Insulation layer for forming recesses 23 ... recess 23a ... Recess for burying magnetic pole tip 23b ... recess for embedding coil 24 ... coil 25 ... Upper recording magnetic pole 25a ... Upper recording magnetic pole tip

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-120632 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 5/31

Claims (6)

(57) [Claims] 1. A thin film magnetic head comprising a lower magnetic pole, an upper magnetic pole formed on the lower magnetic pole via a magnetic gap, and a coil provided between the lower magnetic pole and the upper magnetic pole. The thin-film magnetic head according to claim 1, wherein the lower magnetic pole has a plurality of protrusions on the surface facing the coil, the protrusions being aligned with the formation position of the coil. 2. The thin film magnetic head according to claim 1, wherein the coils are electrically separated by an insulating layer formed between the convex portions adjacent to each other. 3. The thin-film magnetic head according to claim 1, wherein a nonmagnetic insulating layer forming the magnetic gap is formed between at least one of the lower magnetic pole and the upper magnetic pole and the coil. A thin film magnetic head characterized in that 4. The thin film magnetic head according to claim 1, wherein a part of the convex portion is aligned with a formation position of a magnetic pole tip portion of the upper magnetic pole. 5. A method of manufacturing a thin film magnetic head, comprising: a step of forming an upper magnetic pole on a lower magnetic pole via a magnetic gap; and a step of forming a coil between the lower magnetic pole and the upper magnetic pole. A step of forming a plurality of convex portions on the surface of the lower magnetic pole, a step of forming a first insulating layer on the lower magnetic pole, the first insulating layer having a surface reflecting the shape of the convex portion, and the first insulation Formed between the plurality of protrusions on the surface of the layer.
The insulating layer for forming the recessed portion forms a recessed portion that is aligned with the protruding portion .
A step that form, the step of forming the coil in the recess, forming a second insulating layer covering the coil, and forming the upper magnetic pole on the second insulating layer A method for manufacturing a thin film magnetic head, comprising: 6. The method of manufacturing a thin film magnetic head according to claim 5, wherein the tip of the upper magnetic pole is formed in a concave portion that matches a part of the convex portion. .