JP2000187810A - Thin-film magnetic head and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin-film magnetic head which has high writing performance by reducing the leak of magnetic fluxes in an area other than a write gap. SOLUTION: The thin-film magnetic head has a lower core 18 which constitutes a lower pole 18a, a gap layer 20 which is formed on the lower core 18, a 1st upper pole 21 which is formed almost in a rectangular parallelepiped shape opposite the lower core 18, and can upper core 25 whose front end part is constituted by a 2nd upper pole 24 provided on the 1st upper pole 21 and whose rear end part is joined with the lower core 18 near its rear end part. This thin-film magnetic head has a 1st coil 26 for supplying a current for producing write magnetic flux more on the side of the gap layer 20 than a plane containing the top surface of the 1st upper pole 21, and consequently the distance L1 between the coil and write gap is made shorter to reduce the leak of magnetic fluxes in the area other than the write gap.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film magnetic head for writing magnetic information on a magnetic recording medium, and more particularly to a thin-film magnetic head having excellent write performance.

[0002]

2. Description of the Related Art In thin-film magnetic heads used in hard disk drives and the like, overwrite characteristics,
(Non-linear bit shift, also referred to as NLBS). FIG. 15 is a front view, and FIG. 16 is a cross-sectional view taken along the line 1-1 in FIG.

This thin-film magnetic head has a gap layer 53 formed on the upper surface of a lower core 52 constituting a lower pole 51,
A first upper pole 54 provided so as to face the lower pole 51 with the gap layer 53 interposed therebetween, a second upper pole 55 joined to the upper surface of the first upper pole 54, and integrally connected to the second upper pole 55. An upper core 56 joined to the lower core 52 in the rear region to form a magnetic path together with the first upper pole 54, the lower core 52, and the gap layer 53 located between the first upper pole 54 and the lower pole 51; And a coil 58 and the like arranged so as to flow a current interlinking with the magnetic path, and protected by an insulating layer 57.
Is composed of a high saturation magnetic flux density material such as 45 permalloy (45Ni-55Fe: composition is the same in weight ratio, hereinafter the same) so that a dense magnetic flux can be guided to the magnetic recording medium MD.

In such a thin film magnetic head, FIG.
As shown in the figure, the width of the second upper pole 55 is
If the width is smaller than 4, the sufficient magnetic flux cannot be guided to the first upper pole 54. On the other hand, if the second upper pole 55 is formed so that its width is wider than the width of the first upper pole 54 to solve this problem, as shown in FIG. Also, it is formed on both sides of the upper pole 54. Therefore, the above-mentioned thin film magnetic head has a first
The first upper pole burying layer 59 for burying the first upper pole 54 is formed flush with the upper surface of the upper pole 54 to solve the above problem.

[0005]

However, in the above thin film magnetic head, since the coil 58 is formed above the first upper pole buried layer 59, the coil 58 and the write gap (the lower pole 51 and the first upper The distance L between the pole 54 and the gap layer 53) is increased. Therefore, as indicated by the broken line in FIG. 16, the leakage of the magnetic flux in a region other than the write gap increases, and a sufficient magnetic flux cannot reach the first upper pole 54. As a result, the overwrite characteristics And NLTS, high frequency characteristics, and the like are deteriorated. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a thin-film magnetic head having a better write characteristic and less leakage of magnetic flux in a region other than the write gap, and a method of manufacturing the same.

[0006]

SUMMARY OF THE INVENTION A feature of the present invention resides in that part or all of a coil is formed on a gap layer side with respect to a plane including an upper surface of a first upper pole.

According to this feature, as shown in FIG. 2, since the distance L1 between the coil and the write gap can be reduced, the leakage of magnetic flux in a region other than the write gap can be reduced. Therefore, the writing characteristics of the thin-film magnetic head can be further improved. In addition,
In this case, another coil may be provided on the coil.

Another feature of the present invention relates to a method of manufacturing such a thin film magnetic head, wherein a lower core constituting a lower pole on a substrate, a gap layer, and the lower pole are opposed to the lower pole via the gap layer. A first upper pole having a substantially rectangular parallelepiped shape, a coil and a non-magnetic insulating layer covering the coil are formed on the gap layer, and then the first upper pole and the insulating layer are formed. A first upper pole buried layer is formed thereon, and then polished so that the upper surface of the first upper pole is flush with the upper surfaces of the first upper pole buried layer and the insulating layer. Forming the upper core.

According to this feature, when the upper core is formed, the upper surface of the first upper pole is flush with the upper surface of the first upper pole embedded layer and the upper surface of the insulating layer. Is not formed immediately above the gap layer. For this reason, in particular, even in a thin film magnetic head in which the materials of the first upper pole and the second upper pole (upper core) are different, the desired performance can be exhibited. Further, since the coil is formed on the gap layer, it is possible to manufacture a thin-film magnetic head having a small distance between the coil and the write gap.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view, and FIG.
-2 section (side section showing a section cut along the center line)
FIG. 1 shows an embodiment of the thin film magnetic head according to the present invention.
In the state, Altic (Al_TwoO_Three-TiC)
Wafer made of lamic material that is later cut
Aluminum on the slider substrate 10 constituting the slider
(Al _TwoO_Three) Or aluminum nitride (AlN)
A protective layer 11 of a magnetic insulating film is formed. This protective layer
On top of 11, a lower seal made of a soft magnetic film such as Permalloy
Layer 12 is embedded so as to be embedded in the protective film 13.
I have.

On the lower shield 12 and the protective film 13,
A reproducing gap 14 made of a non-magnetic insulating film such as alumina or aluminum nitride is formed. On the lower reproducing gap 14, a pair of leads 15a and 15b in which a bias magnet film made of CoCrPt or the like and an electric conductive film made of W, Ta, Nb or the like are laminated are formed.

The magnetoresistive element (MR element, GMR element) 16 has a lower reproducing gap 14 exposed on the inclined surface of the trapezoidal groove formed by the pair of leads 15a and 15b and the bottom surface of the trapezoidal groove. Is formed on the upper surface.

The magnetoresistive element 16, the leads 15a, 1
5b and the reproducing gap 14 exposed therearound
A reproduction gap 17 made of an insulating film such as alumina or aluminum nitride is formed on the substrate.
An upper shield (hereinafter, referred to as a lower core) made of a soft magnetic material such as 81 permalloy (81Ni-19Fe) also serves as a lower core.
Called "lower core". ) 18 are formed so as to be embedded in the protective film 19. The above-described lower shield 12 to the lower core 18 constitute a reproducing head, and the substrate 10 to the reproducing upper gap 17 constitute a recording head substrate described below. Note that the lower core 18 and the lower pole 18a are integrally formed, and the lower core 18 in a region near the surface (magnetic recording medium facing surface) S facing the magnetic recording medium MD effectively constitutes the lower pole 18a. I have.

A gap layer (writing gap film) 20 made of an insulating film such as alumina is formed on the upper surface of the lower core 18. A lower pole 18 a is provided on the upper surface of the lower core 18 and immediately above the magnetoresistive element 16. A substantially rectangular parallelepiped first upper pole 21 made of a high saturation magnetic flux density material is formed so as to face the first upper pole 21. As this high saturation magnetic flux density material, in addition to 45 permalloy (45Ni-55Fe), 94Co-6F
e, FeTaN, 30Fe-25Co-45Ni, etc. can be adopted.

On the upper surface of the gap layer 20 and behind the first upper pole 21 (in a direction perpendicular to the magnetic recording medium facing surface S and from the magnetic recording medium facing surface S to the first upper pole 21 or the magnetoresistive element). 16 is formed, that is, FIG.
In the right direction), alumina, SiO ₂ , SiC,
A first coil insulating layer 22 made of a non-magnetic and insulating material such as AlN is formed. In addition, the first surface is located on the upper surface of the gap layer 20 except for the first coil insulating layer 22.
An upper pole burying layer 23 is formed, and the first coil insulating layer 22, the first upper pole burying layer 23, and the first upper pole 21 are formed.
Are flush with each other.

A second upper pole 24 having a substantially rectangular parallelepiped shape is laminated on the first upper pole 21. The second upper pole 24 is made of 81 permalloy, and has substantially the same width as the first upper pole 21 in the direction of the plane formed by the layers (the left-right direction in FIG. 1).

The upper core 25 is made of 81 permalloy and has an arc shape in cross section as shown in FIG. 2, and has one end (that is, the surface S facing the magnetic recording medium).
Is the second upper pole 24. The upper core 25 is joined to the lower core 18 at the other end (near the rear end), and the lower core 18, the first upper pole 21,
The second upper pole 24, and the first upper pole 21 and the lower core 18
And a magnetic path is formed in cooperation with the gap layer 20 interposed therebetween. The gap layer 20 interposed between the first upper pole 21 and the lower core 18 is also called a write gap.

A plurality of first coils 26 are provided on the first coil insulating layer 22 described above. The first coil 26 is formed in such a pattern that a current interlinking with the magnetic path formed by the upper core 25, the lower core 18, and the like flows.

A plurality of second coils 28 embedded in a second coil insulating layer 27 are formed between the upper core 25 and the first coil insulating layer 22. Similarly to the first coil 26, the second coil 28 is formed in a pattern such that a current interlinking the magnetic path formed by the upper core 25, the lower core 18, and the like flows. The lower core 18 to the upper core 25 described above constitute a recording head.

Next, the manufacturing process of the recording head in the above-described thin film magnetic head will be described with reference to FIGS. In each of the drawings, (A) is a front view of a thin-film magnetic head in the course of manufacture as viewed from a magnetic recording medium facing surface S to be formed later, and (B) is a cross section cut along the center line of the thin-film magnetic head. FIG. First, as shown in FIG. 3, the reproduction gap 1 formed on the pair of leads 15a and 15b and the magnetoresistive element 16 is formed.
The lower core 18 (including the lower pole 18a) made of 81 permalloy is formed on the upper surface 7, and the upper surface thereof is polished and flattened.

Next, as shown in FIG. 4, an alumina film 30 is deposited on the upper surface of the lower core 18 by sputtering, and thereafter, as shown in FIG. 5, the upper surface of the alumina film 30 is polished and flattened. I do. Thereby, the lower core 18 is surrounded by the protective film 19 made of alumina, and the upper surface of the lower core 18 and the upper surface of the protective film 19 are flush.

Next, as shown in FIG. 6, a non-magnetic insulating film made of alumina or the like is deposited on the lower core 18 and the protective film 19 by sputtering or the like to form a gap layer 20. Thereafter, as shown in FIG. 7, a resist film 31 is formed on the flat surface of the gap layer 20, and a first film to be formed in a later step is formed.
The resist film 31 is patterned by photolithography using a mask 40 conforming to the shape of the upper pole 21. As a result, as shown in FIG. 8, the resist film 31 has a shape having an opening 31a at a position matching the first upper pole 21 to be formed.

Subsequently, as shown in FIG. 9, 81 permalloy is plated and buried in the opening 31a of the resist film 31, and then the resist film 31 is removed to form the first upper pole 21. The above resist film 31
Is formed on the upper surface of the flat gap layer 20, the resist film 31 can be formed thin. For this reason,
The first upper pole 21 can be accurately formed without lowering the exposure resolution of photolithography.

Next, as shown in FIG. 10, copper (Cu) having a predetermined pattern is provided behind the first upper pole 21.
Is formed by plating. At this time, the plating time and the like are adjusted such that the upper surface height of the first coil 26 is substantially the same as the height of the upper surface of the first upper pole 21 formed. The plating is performed by forming a resist (not shown) having a predetermined pattern, and removing the resist after the plating.

Next, as shown in FIG. 11, the first coil 26 is covered so as not to cover the first upper pole 21.
The coil insulating layer 22 is formed. The first coil insulating layer 22 may be formed so as to cover the first coil 26 and the first upper pole 21. As will be described later, the upper surface of the first coil insulating layer 22 is polished until the upper surface of the first upper pole 21 is exposed, and the first coil formed on the left side (front) with respect to the alternate long and short dash line in FIG. This is because the insulating layer 22 is removed by a throat height adding process (a process of adjusting the throat height by polishing).

Next, as shown in FIG. 11, alumina 32 is deposited on the exposed upper surfaces of the gap layer 20, the first upper pole 21, and the first coil insulating layer 22 by sputtering. Next, as shown in FIG. 12, the upper surfaces of the first upper pole 21, the first coil insulating layer 22, the alumina 32, and the first coil 26 are polished and flattened, and these upper surfaces are flush with each other. . As a result of the polishing, the alumina 32 becomes the first upper pole embedded layer 23.

Thereafter, as shown in FIG. 13, a second coil insulating layer 27 and a second coil 28 (made of copper) penetrating through the second coil insulating layer 27 are formed on the first coil insulating layer 22. ) Is formed. Next, as shown in FIG. 14, the upper core 25 is formed on the second coil insulating layer 27 by plating. At this time, the second upper pole 24 is formed above the first upper pole 21 at the same time. Finally, after covering the upper core 25 and the like with a protective film (not shown), FIG.
The thin film magnetic head having the structure shown in FIGS. 1 and 2 is formed by cutting at the surface indicated by the one-dot chain line in (B) and polishing the cut surface to adjust the throat height.

As described above, in the present embodiment, the first coil 26 is formed in the first coil insulating layer 22 (the gap between the first coil 26 and the plane including the upper surface of the first upper pole 21 is smaller than that of the first coil 26). 2), the distance L1 between the write gap and the coil as shown in FIG.
Can be reduced to, for example, about 10 μm or less, and leakage of magnetic flux in portions other than the write gap can be reduced. In addition, since the first coil 26 is formed in the first coil insulating layer 22, the first coil 26
Does not come into contact with the inclined portion of the upper core 25, and
There is no need to dispose the second coil 28 excessively close to the upper core 25 in order to prevent leakage of magnetic flux, so that the reliability of the thin-film magnetic head is improved.

According to the above-described manufacturing method, when the second upper pole 24 is formed (ie, when the upper core 25 is formed), the upper surface of the first upper pole 21 is formed on the upper surface of the first coil insulating layer 22.
In addition, since the second upper pole 24 is flush with the upper surface of the first upper pole burying layer 23, the second upper pole 24 is not formed immediately above the gap layer 20 around the side surface of the first upper pole 21. This makes it possible to manufacture a thin-film magnetic head in which the first upper pole 21 is formed of a high saturation magnetic flux density material and guides a sufficient magnetic flux to the write gap.

The present invention is not limited to the above embodiment,
The present invention is applicable to other thin film magnetic heads. The modified examples will be listed below.

(1) In the above embodiment, the first coil 26 and the second coil 28 are provided to form a plurality of coil layers. However, only one layer of the first coil 26 is provided. You may. (2) In the above-described embodiment, the upper surface of the lower pole 18a and the upper surface of the lower core 18 are flush with each other.
The lower pole 18a may be formed to project from the lower core 18 by performing ion milling processing from the upper surface using the mask as a mask.

(3) In the above embodiment, the lower core 1
Between the first coil insulating layer 22 and the first coil insulating layer 22 is the gap layer 2.
0, but another insulating film is formed between the gap layer 20, the first coil insulating layer 22, and the first coil 26 to improve the insulating property of the first coil 26. Is also good. (4) In the above embodiment, the second upper pole 24 is formed to have substantially the same width as the first upper pole 21.
The upper pole 24 may be formed wider than the first upper pole 21.

(5) In the above-described embodiment, the second upper pole 24 is formed at a position facing the magnetic recording medium facing surface S. However, the second upper pole 24 is slightly moved backward (to the right in FIG. 2) from the magnetic recording medium facing surface S. It may be provided by shifting only.
(6) The first coil insulating layer 22 may be a resist or alumina deposited by sputtering. (7) In the above embodiment, the thin-film magnetic head having the reproducing head using the magnetoresistive element 16 has been described. However, a thin-film magnetic head having a so-called inductive reproducing head may be used. (8) In the above embodiment, the entire first coil 26 is embedded in the first coil insulating layer 22, but a part of the first coil 26 is partially embedded in the first coil insulating layer 22.
It may be formed to be located inside.

[Brief description of the drawings]

FIG. 1 is a front view of a thin-film magnetic head according to the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

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

FIG. 5 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 6 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 7 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 8 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 9 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 10 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 11 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 12 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 13 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 14 is a diagram showing a manufacturing process of the thin-film magnetic head shown in FIG.

FIG. 15 is a front view of a thin-film magnetic head proposed by the present applicant.

16 is a sectional view taken along the line 1-1 in FIG. 15;

FIG. 17 is a view for explaining the reason why the upper surface of the first upper pole is flush with the upper surface of the protective layer.

FIG. 18 is a view for explaining the reason why the upper surface of the first upper pole is flush with the upper surface of the protective layer.

[Explanation of symbols]

10 ... substrate, 11 ... protective layer, 12 ... lower shield, 13 ...
Protective film, 14: reproduction lower gap, 15a, 15b: pair of leads, 16: magnetoresistive element, 17: reproduction upper gap, 18: lower core (upper shield and lower core), 18a ...
Lower pole, 19: protective film, 20: gap layer (write gap film), 21: first upper pole, 22: first coil insulating layer, 23: first upper pole buried layer, 24: second upper pole, 25: upper core, 26: first coil, 27: second coil insulating layer, 28: second coil.

Claims (2)

[Claims] 1. A lower core constituting a lower pole formed on a substrate, a gap layer formed on the lower core, and formed on the gap layer to face the lower pole. A first upper pole having a substantially rectangular parallelepiped shape;
A thin-film magnetic head having a second upper pole provided on the upper pole as a leading end and an upper core joined to the lower core near the rear end to form a magnetic path; A part or all of a coil for passing a current interlinking with the magnetic path on a side of the gap layer with respect to a plane including: 2. A step of forming a lower core constituting a lower pole on a substrate, a step of forming a gap layer on the lower core, and substantially opposing the lower pole via the gap layer. A step of forming a first upper pole having a rectangular parallelepiped shape, a step of forming a coil on the gap layer, a step of forming a non-magnetic insulating layer covering the coil, the first upper pole and the insulation Forming a first upper pole buried layer on the layer; and forming the first upper pole buried layer so that an upper surface of the first upper pole is flush with an upper surface of the first upper pole buried layer and the insulating layer. Polishing the pole buried layer, the first upper pole, and the insulating layer; and forming a second upper pole on the first upper pole and joining the lower core across the insulating layer. Forming a core; and a thin film comprising: Manufacturing method of the gas head.