JP2971212B2 - Method for manufacturing thin-film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thin film magnetic head used for a magnetic recording device such as an HDD or a computer. The present invention relates to a manufacturing method which is manufactured by:

[0002]

2. Description of the Related Art A floating type thin film magnetic head uses a dynamic pressure generated by the viscosity of air generated when moving at a high speed relative to a recording medium such as a magnetic disk, and makes a contact with a magnetic disk surface. A small flying height is generated, and is used for a read / write magnetic head such as an HDD.

An example of the structure of the thin-film magnetic head manufactured according to the present invention will be described with reference to FIG. As shown in FIG. 1, a first insulating layer 2, a first magnetic pole layer 3, a nonmagnetic material layer 4 serving as a gap portion, and a second magnetic pole layer 5 are sequentially stacked on the upper surface of the substrate 1. The first and second magnetic pole layers 3 and 5 are connected at their rear end portions, although not shown, and constitute a yoke.
Also, the first and second magnetic pole layers 3 and 3 on the rear side of the nonmagnetic material layer 4
A predetermined number of coil layers 7 are formed in the region A between the layers 5 with the insulating layer 6 interposed therebetween.

The first and second magnetic pole layers 3, 5
Is made of Ni—Fe permalloy, and the magnetic pole layers 3 and 5 are usually formed by a plating method. In this plating method, first, a plating base layer 3a made of Ni—Fe permalloy is formed on a surface on which the first pole layer 3 is formed, that is, on a surface of the first insulating layer 2 by using a vapor deposition device or the like.
To form Next, while the plating base layer 3a is inserted in the electrolytic solution, a current is applied to the plating base layer 3a. Thereby, electroplating is performed, and the plating base layer 3 is formed.
A plating layer 3b having a predetermined thickness is formed above a. Also,
Similarly, when forming the second magnetic pole layer 5, a plating base layer 5a is formed on the upper surface of the nonmagnetic material layer 4 by vapor deposition, and then electroplating is performed to form a plating layer 5b above the plating base layer 5a. .

The plating base layers 3a, 5a
Is a base material for forming the plating layers 3b and 5b, so that the current can flow reliably and the plating layers 3b and 5b can be uniformly formed.
The film thickness is usually 2000-3000 to grow b
Angstroms or more, and the composition ratio of Ni is 80 wt% and Fe is 20 wt%.
It is about wt%. The thickness of each of the plating layers 3b and 5b is about 3 μm, and a magnetic flux is generated between the plating layers 3b and 5b as shown by a two-dot chain line in the figure.

[0006]

With the recent increase in recording density in a recording medium, the thin-film magnetic head has been miniaturized, and the film thickness of the pole layers 3 and 5 has been extremely reduced to 1 μm or less. . Then, the abundance ratio of the plating base layers 3a and 5a in the pole layers 3 and 5 becomes large, and the magnetic characteristics of the plating base layers 3a and 5a greatly affect the characteristics of the thin film magnetic head itself. Especially,
The effect of the plating base layer 5a of the second magnetic pole layer 5 adjacent to the nonmagnetic material layer 4 becomes significant. Then, as described above, when the thickness of the plating base layers 3a and 5a becomes 2000 to 3000 Å, the plating base layers 3a and 5a become
Since the magnetic anisotropy in (a) is deteriorated, the magnetic characteristics of the thin-film magnetic head itself deteriorate.

On the other hand, the base plating layers 3a, 5a
Has been used only for the purpose of forming the plating layers 3b and 5b as described above, so that the composition of the
i: 80 wt%, Fw: 20 wt%). As a result, there arises a problem that the magnetic characteristics between the elements vary.

The present invention has been made in view of the above background, and an object of the present invention is to improve the magnetic characteristics of a thin-film magnetic head itself and to provide a thin-film magnetic head with less variation between elements. It is to provide a manufacturing method.

[0009]

In order to achieve the above object, in a method of manufacturing a thin-film magnetic head according to the present invention, a first pole layer constituting a part of a yoke is provided on a substrate, and A non-magnetic material layer constituting a gap is provided on the magnetic pole layer, and a second magnetic pole layer is provided on the non-magnetic material layer, and the second magnetic pole layer is formed of the insulating layer. A plating base layer made of Ni-Fe is provided on the surface by sputtering or vapor deposition, and then the plating base layer is inserted into an electrolytic solution and an electric current is applied to form a Ni-Fe plating layer on the plating base layer. In a method of manufacturing a thin film magnetic head formed by growing,
The plating base layer has a thickness of 500 to 1000 Å and a composition ratio of Ni: 83.5 ± 0.5 wt.
%, Fe: 16.5 ± 0.5 wt%.

[0010]

According to the present invention, there is provided a base plating layer (particularly, a second magnetic pole layer adjacent to a non-magnetic material layer forming a gap) which has been used only as a base for forming a plating layer which occupies most of the magnetic pole layer. Of the final magnetic head as a part of the magnetic circuit (yoke) in the final magnetic head. In other words, the magnetic flux flowing through the first and second magnetic poles once exits from the end face of one pole layer to the outside at the gap, and enters into the interior from the end face of the other pole layer. A large amount of magnetic flux flows near both sides of the nonmagnetic material layer. Therefore, by manufacturing a base plating layer of the second pole layer adjacent to the non-magnetic material layer using a material having good magnetic properties, magnetic flux easily passes through the plating base layer, and a loss or the like there is reduced. Play a role in reducing. In the present invention, a plating base layer having a film thickness and a composition suitable for that purpose is manufactured, and specific reasons for the limitation are as follows.

That is, the reason why the film thickness is set to 500 to 1000 angstroms is that if the thickness is less than 500 angstroms, the base plating layer cannot be uniformly deposited, and as a result, when a subsequent plating layer is formed, This is because they cannot be grown uniformly. On the other hand, if the film thickness is small, the resistance value increases, and the original role of energizing the plating base and growing the plating layer cannot be sufficiently achieved. On the other hand, if the thickness is more than 1000 Å, the magnetic anisotropy will deteriorate.

The composition ratio is Ni: 83.5 ± 0.5 w
t% and Fe: 16.5 ± 0.5 wt% are obtained from Ni.
Is 83.5 wt% (the balance is Fe), the coercive force Hc is the smallest, and the magnetostriction λ is also zero, so that the magnetic characteristics become the best. Then, an allowable error range of ± 0.5
The reason for this is that within this range, no significant deterioration in magnetic properties is observed, and the accuracy of the vapor deposition device and the like is about ± 0.1 with respect to the target value. Therefore,
Most preferably, the target value of Ni is 83.5 wt%.
It is to be.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the method for manufacturing a thin film magnetic head according to the present invention will be described below. In this embodiment, a thin-film magnetic head having the structure shown in FIG. 1 is manufactured. First, a first insulating layer 2 is formed on the upper surface of a substrate 1 by the same means as in the prior art, and then the first insulating layer 2 is formed. The first magnetic pole layer 3
Is formed by an electroplating method. In this example, the first pole layer 3 was also manufactured by the method of the present invention. That is, first, the plating base layer 3a is formed by using an evaporation apparatus. In addition, you may form by sputtering instead of vapor deposition. At this time, the film thickness is adjusted to be 500 to 1000 angstroms, and the composition ratio is 83.5 ± 0.5 Ni.
It is manufactured to contain 5 wt% and Fe: 16.5 ± 0.5 wt%. Of course, other minute components may be included.

Next, the plating base layer 3a is inserted and arranged in an electrolytic cell, and a plating layer 3b is grown to a predetermined thickness on the upper surface of the plating base layer 3a by passing electricity. The plating layer 3b is also formed so that the target values of the composition ratio are Ni: 83.5% by weight and Fe: 16.5% by weight. In this embodiment, the film formation process is performed in a magnetic field to impart magnetic anisotropy and improve magnetic properties. Further, in the present embodiment, after the formation of the plating layer 3b, the magnetic anisotropy is more reliably formed by performing a heat treatment in a magnetic field. still,
The film formation in a magnetic field and the heat treatment in a magnetic field are not necessarily performed, and only one of them may be performed.

Thereafter, a non-magnetic material layer 4 serving as a gap is formed on the first magnetic pole layer 3 by a method similar to the conventional method.
Next, a predetermined number of insulating layers 6 and coil layers 7 are arranged on the rear upper surface of the nonmagnetic material layer 4.

Next, the second pole layer 5 which is the gist of the present invention will be described.
Is performed. That is, the second magnetic pole layer 5 is formed on the upper surface of the nonmagnetic material layer 4 to be the gap portion and on the upper surface of the uppermost insulating layer 6. In the present invention, the second magnetic pole layer 5 is formed. Is manufactured by electroplating, first, a plating base layer 5a having a desired film thickness and composition is manufactured by vapor deposition or sputtering, and then electroplating is performed, and plating of a predetermined thickness is performed on the upper surface of the plating base film 5a. The layer 5b is manufactured. Although the specific manufacturing process of the plating base layer 5a is performed in the same manner as the manufacturing process of the plating base film 3a of the first magnetic pole layer 3, the manufacturing process is not necessarily the same as long as it is within a predetermined range. do not have to. Further, the subsequent steps of forming the plating layer 5b and imparting magnetic anisotropy were performed in the same manner. And this second pole layer 5
Was formed, the upper surface thereof was covered with a protective film 8.

* Experimental Results The thickness of the nonmagnetic material layer 4 was set to 0.3 μm,
The thickness of the plating base layer 5a is 700 Å, and the thickness of the plating layer 5b of the second pole layer 5 is 0.8 μm.
Then, a thin-film magnetic head was prepared (the other configurations were within the range of the above-described embodiment), and the change of the head output with respect to the writing frequency f at that time was measured. As a comparative example, the thickness of the plating base layer 5a was 2
A thin-film magnetic head was manufactured with the same configuration as above except that the thickness was set to 2,000 angstroms, and the change of the head output with respect to the writing frequency at that time was measured. FIG. 2 shows the experimental results. As is clear from the figure, it can be seen that the product of the present invention has improved head output.

Next, the thickness of the plating base layer 5a was changed (other configurations were within the range of the above-described embodiment), and the change of the holding force Hc at that time was measured. Shown in As shown in the figure, regardless of the presence or absence of the heat treatment, the holding force Hc is stable at 1000 Å or less, and when it exceeds that, the holding force Hc rapidly increases. That is, when the thickness exceeds 1000 angstroms, the magnetic properties are deteriorated.

[0019]

As described above, in the method of manufacturing a thin-film magnetic head according to the present invention, the plating base layer of the second magnetic pole layer adjacent to the nonmagnetic material layer forming the gap is formed with a thickness of 50 nm.
0 to 1000 angstroms, and the composition ratio is Ni:
83.5 ± 0.5 wt%, Fe: 16.5 ± 0.5 wt
%, The magnetic properties such as the coercive force and magnetostriction of the plating base layer constituting a part of the magnetic circuit are improved. As shown by the solid line in FIG. 1, magnetic flux is generated in the plating base layer. The loss smoothly flows with little loss, and the magnetic properties as a final thin film magnetic head are improved. In addition, since the film thickness and the composition ratio are adjusted with high precision, there is little variation between elements, and stable performance can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an example of a thin-film magnetic head.

FIG. 2 is a graph showing a change in head output with respect to a writing frequency of a product of the present invention and a conventional product.

FIG. 3 is a graph showing a change in a holding force with respect to a film thickness of a plating base layer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 3 1st magnetic pole 4 Nonmagnetic material layer 5 2nd magnetic pole 5a Plating base layer 5b Plating layer

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-57-24015 (JP, A) JP-A-4-157607 (JP, A) JP-A-4-163707 (JP, A) JP-A-5-205 73839 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) G11B 5/31

Claims (1)

(57) [Claims] 1. A first magnetic pole layer forming a part of a yoke is provided on a substrate, a nonmagnetic material layer forming a gap is provided on the first magnetic pole layer, and a nonmagnetic material layer is formed on the nonmagnetic material layer. Is provided with a second magnetic pole layer, and the second magnetic pole layer comprises:
Ni-Fe is formed on the surface of the insulating layer by sputtering or vapor deposition.
And a thin film formed by inserting a plating base layer into an electrolytic solution and applying a current to grow a Ni—Fe plating layer on the plating base layer. In the method for manufacturing a magnetic head, the plating base layer has a thickness of 500 to 1000 Å and a composition ratio of Ni: 83.5 ± 0.5 wt.
%, Fe: 16.5 ± 0.5 wt%.