JPH07141629A - Production of magneto-resistance effect type magnetic head - Google Patents

Abstract

PURPOSE:To decrease noises by forming a first metallic film on at least a region which is the track width of an MR element layer and allowing this first metallic film to exist at the time of removing the track width region of the second metallic film. CONSTITUTION:The first metallic film 20 is so formed as to cover the MR element layer 15. Next, the second metallic film 16 is formed over the entire surface of a substrate so as to cover the first metallic film 20. The second metallic film 16 is an electrode layer and is formed by using Au in such a case. The first metallic film 20 is formed to the same pattern shape as the pattern shape of the electrode layer. The first metallic film exists at the time of removing the track width region of the second metallic film and, therefore, the damaging of the MR element layer by the removing work is prevented.

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 magnetoresistive effect magnetic head for converting a magnetic signal into an electric signal by using the magnetoresistive effect and reproducing the electric signal.

[0002]

2. Description of the Related Art A magnetic resistance effect type magnetic head (hereinafter referred to as MR
The head) has a high reproduction sensitivity and its reproduction output does not depend on the relative speed between the medium and the head. Therefore, it is attracting attention as a magnetic head useful for downsizing and high density of the magnetic recording apparatus. As a magnetic head used in a magnetic recording device such as a magnetic disk device, a recording / reproducing separated type composite thin film magnetic head in which recording is performed by an inductive magnetic head and reproduction is performed by an MR head is considered promising. A thin-film magnetic head has a magnetic circuit, a conductor coil, and electrodes formed on a substrate by applying a thin-film deposition method and photolithography technology.Compared to a conventional bulk-type head consisting of a magnetic core and windings. Therefore, it is easy to reduce the size and increase the density.

In such a thin-film magnetic head, there is a recent demand for higher density in a magnetic disk device, so that a narrower track and a narrower depth are required. Therefore, magnetic domain control is important in the MR head, and in the magnetoresistive effect element layer (hereinafter referred to as MR element layer), the magnetoresistive effect film (hereinafter referred to as MR film) is
A magnetic domain control film, and a structure having a shunt film or a soft film added are being studied.

8 to 10 are views showing a conventional MR head, FIG. 8 is a plan view, FIG. 9 is a sectional view taken along line AA of FIG. 8, and FIG. It is sectional drawing which follows the BB line of FIG. With reference to FIGS. 8 to 10, an insulating layer 2 is provided on a nonmagnetic substrate 1, and a lower shield layer 3 patterned into a predetermined shape is provided on the insulating layer 2. An insulating layer 4 is formed on the lower shield layer 3, and an MR element layer 5 is provided on the insulating layer 4. MR element layer 5
A pair of the electrode layers 6a, 6a, 6a, 6
b is provided. The insulating layer 7 is formed on the pair of electrode layers 6a, 6b and the surface 5a of the MR element layer 5 between them.
And the upper shield layer 8 is formed on the insulating layer 7. In FIG. 8, the lower shield layer 3 and the MR element layer 5 are
And only the electrode layers 6a, 6b are shown.

In the conventional MR head as described above,
For the electrode layers 6a and 6b, after forming a metal film to be an electrode layer on the entire surface of the substrate, unnecessary portions are removed by etching,
The pattern is formed as shown in FIG.

[0006]

However, during the etching for forming such an electrode, a portion of the surface 5a of the MR element layer 5 is damaged, and it becomes impossible to obtain a good magnetoresistive effect characteristic. There was a problem. M
The R element layer is usually formed of a multilayer film, and each film is formed of a very thin film of several hundred liters. For example,
There is a case where an antiferromagnetic film such as Fe-Mn is laminated as a magnetic domain control film on an MR film made of a Ni-Fe film to form an MR element section. If it is formed, the antiferromagnetic film may be damaged by contact with an etchant or etching gas during etching for forming the electrode. In particular, F
The antiferromagnetic film such as e-Mn is a material that easily oxidizes and corrodes, and its upper surface and edge are easily damaged during etching for forming an electrode. Therefore, there is a problem that stable magnetic domain control cannot be performed and causes noise such as Barkhausen noise.

In addition to the magnetic domain control film, Ti, Ta, Z
A metal film such as r, Nb, Cr, or Mo is used as a shunt film for M
The R element layer may be formed as a constituent film, or a metal film made of a Co-based amorphous material may be formed as a soft film. Such a film may be damaged during etching for forming an electrode and desired film may be formed. There is also a problem that the magnetoresistive effect characteristics cannot be obtained.

An object of the present invention is to provide a method for manufacturing an MR head which solves the above-mentioned conventional problems and is not damaged by etching during electrode formation.

[0009]

The manufacturing method of the present invention is
A method of manufacturing an MR head in which a pair of electrode layers are provided on the R element layer at a distance corresponding to the track width,
A step of forming a first metal film so as to cover at least a region having a track width of the MR element layer, and a second metal film serving as an electrode layer above the MR element layer on which the first metal film is formed And a step of forming a pair of electrode layers by removing the track width region of the second metal film so that the first metal film remains.

The MR head of the present invention comprises an MR element layer and an M element.
A first metal film formed so as to cover at least a region having a track width of the R element layer, and an electrode layer provided for flowing a detection current to the MR element layer, and the first metal film is formed. A second metal film formed by forming a second metal film on the formed MR element layer and removing a track width region of the second metal film so that the first metal film remains. It is characterized by including a pair of electrode layers.

In the present invention, since the second metal film is a film which becomes an electrode layer, the materials of the first metal film and the second metal film are made so that the specific resistance is smaller than that of the first metal film. Is preferably selected.

[0012]

According to the present invention, the first metal film is formed so as to cover at least the region of the MR element layer which becomes the track width, and the MR element layer on which the first metal film is formed is formed. A second metal film to be an electrode layer is formed on the first metal film, and the track width region of the second metal film is removed so that the first metal film remains, and the electrode layer is formed. When the track width region of the second metal film is removed to form the electrode layer, the first metal film exists in the track width region of the MR element layer.
Protected by this first metal film, the MR element layer is not damaged.

For example, when the track width region of the second metal film is removed by etching, the second metal film and the first metal film are selectively etched so that only the second metal film is selectively etched. If the material is selected, only the second metal film can be selectively etched to remove the track width region.

[0014]

1 is a sectional view showing an embodiment of a manufacturing method according to the present invention. 2 and 3 are plan views of the embodiment shown in FIG. Referring to FIG. 1A, the lower shield layer 13 is formed on the insulating layer 12 formed on the non-magnetic substrate.
To form. The lower shield layer 13 is, for example, Ni-Fe.
A soft magnetic film such as the above is formed on the entire surface of the insulating layer 12 by a method such as sputtering or vapor deposition so as to have a film thickness of about 0.5 to 3.0 μm, and then etched and patterned to have a predetermined shape. FIG. 2A is a plan view corresponding to FIG.

Next, referring to FIG. 1B, an insulating layer 14 is formed so as to cover the lower shield layer 13. The insulating layer 14 can be formed of, for example, a thin film of SiO ₂ or Al ₂ O _{3 having} a film thickness of 0.05 to 0.5 μm. The MR element layer 15 is formed on a predetermined portion of the insulating layer 14. FIG. 2B is a diagram corresponding to FIG. 1B and shows a position where the MR element layer 15 is formed. M
The R element layer 15 includes, for example, a Ni—Fe film (film thickness 150 to 600 Å) as an MR film, and an Fe— film as a magnetic domain control film.
Mn film (film thickness 50-300Å), M as shunt film
An o film (film thickness 50 to 300 Å) can be formed by stacking by a method such as sputtering or vapor deposition. The MR element layer 15 is formed on the entire surface of the substrate and then patterned into a predetermined shape by etching.

Next, referring to FIG. 1C, a first metal film 20 is formed so as to cover the MR element layer 15. As the first metal film, for example, Ti, Zr, Hf, Nb, Ta
A metal film such as Ti can be used, and Ti is used in this embodiment. The film is formed so as to have a thickness of about 50 to 300Å. The first metal film 20 may be formed on the entire surface of the substrate and then patterned into a predetermined shape by etching. Next, the second metal film 16 is formed on the entire surface of the substrate so as to cover the first metal film 20.
The second metal film 16 serves as an electrode layer, and is formed using Au in this embodiment. Film thickness is 500-200
It is formed so as to be about 0Å. FIG. 2C shows FIG.
It is a figure corresponding to (c), and has shown the pattern shape of the 1st metal film 20. The pattern shape of the first metal film 20 is formed to be the same as the pattern shape of the electrode layer described later. The etching can be performed by wet etching, dry etching, or the like.
As the dry etching, methods such as ion beam etching (IBE) and reactive ion etching (RIE) can be adopted.

Next, referring to FIG. 1D, the second electrode film is etched to form a predetermined shape as an electrode layer, and the second metal film in the region of the track width W is formed. Then, the pair of electrode layers 16a and 16b is formed. The end faces of the electrode layers 16a and 16b are separated from each other by a track width W and define the track width W. When etching to define such track width,
Since the first metal film 20 is provided below the second metal film, M provided below the first metal film 20.
The R element layer 15 is not damaged. Further, since the first metal film 20 completely covers the side surface portion of the MR element layer 15, the side surface portion is not damaged. The etching of the second metal film for forming such an electrode layer can be performed by wet etching or dry etching such as IBE or RIE. When Ti is used as the first metal film and Au is used as the second metal as in the present embodiment, K
By using I and the etchant composed of I, selective etching can be performed. In such selective etching, only Au is etched and Ti is not etched, so that management in the manufacturing process becomes easy. FIG. 3A is a diagram corresponding to FIG. 1D, in which the electrode layers 16 a and 16 b are formed in substantially the same region as the first metal film 20, and only the portion having the track width W is formed. The second metal film 20 is removed and is exposed.

Next, referring to FIG. 1E, an insulating layer 17 is formed on the entire surface of the substrate. The insulating layer 17 is, for example, SiO.
It can be formed by providing a thin film of ₂ or Al ₂ O ₃ with a thickness of 0.05 to 0.5 μm. Further, the upper shield layer 18 is formed above the region of the lower shield layer 13. The upper shield layer 18 can be provided by forming a soft magnetic film such as Ni—Fe with a thickness of 0.5 to 3.0 μm by a method such as sputtering or vapor deposition.
The upper shield layer 18 is formed on the entire surface of the substrate and then processed into a predetermined shape by etching or the like. Figure 3 (b) shows
It is a top view corresponding to FIG.1 (e).

After the MR head is manufactured as described above, the substrate is divided into chips. FIG. 4 is a plan view showing the MR head thus made into a chip, FIG. 6 is a sectional view taken along the line AA shown in FIG. 4, and FIG. 7 is taken along the line BB shown in FIG. FIG. After chipping in this way, polishing is applied to control the depth length,
As shown in FIG. 5, the sliding surface 19 is formed.

As described above, in this embodiment, the first metal film is formed so as to cover the MR element layer, the second metal film to be the electrode layer is formed thereon, and then the second metal film is formed. The track width region of the film is removed by etching. At the time of removal by this etching, the MR element layer is not damaged because the first metal film is present on the MR element layer.

In the above embodiment, the first metal film is formed and etched into a predetermined shape, then the second metal film is formed, and the second metal film is formed.
The metal film is formed into a predetermined shape and the track width region is removed by etching. However, the present invention is not limited to such a manufacturing process. A manufacturing process in which the first metal film and the second metal film are etched into a predetermined shape after the second metal film is laminated and formed on the entire surface, and then the track width of the second metal film is etched. May be adopted.

In the above embodiments, the MR element structure in which the shunt film is provided in the MR element layer is taken as an example, but the present invention is not limited to such an MR element structure, and the shunt film is the MR element. It may be provided in a region outside the layer.

In the above embodiment, the shunt bias type MR head using the shunt film is taken as an example.
The present invention is also applicable to other types, for example, a soft bias type MR head provided with a soft film.

The MR head of the present invention is naturally applicable to the manufacture of an MR head of a composite type thin film magnetic head combined with an induction type magnetic head. Further, the first metal film formed in the present invention may have a function of a shunt film or the like as long as the first metal film is not significantly damaged during the removal processing of the track width region of the second metal film. Good.

[0025]

According to the present invention, the first metal film is formed on at least the region having the track width of the MR element layer, and the first metal film is removed when the track width region of the second metal film is removed. Since the metal film of 1 is present, it is possible to prevent the MR element layer from being damaged by the removal processing. Therefore, there is no damage to the MR film or the magnetic domain control film in the MR element layer, stable magnetic domain control is possible, and an MR head with less noise can be manufactured.

[Brief description of drawings]

FIG. 1 is a sectional view showing a manufacturing process of an embodiment according to the present invention.

FIG. 2 is a plan view showing a manufacturing process of the embodiment shown in FIG.

FIG. 3 is a plan view showing a manufacturing process following that of FIG. 2;

FIG. 4 is a plan view showing an MR head obtained according to an embodiment of the present invention.

5 is a plan view showing a state in which the MR head shown in FIG. 4 has been polished.

6 is a sectional view taken along the line AA shown in FIG.

7 is a cross-sectional view taken along the line BB shown in FIG.

FIG. 8 is a plan view showing a conventional MR head.

9 is a sectional view taken along the line AA shown in FIG.

10 is a sectional view taken along line BB shown in FIG.

[Explanation of symbols]

 12 ... Insulating layer 13 ... Lower shield layer 14 ... Insulating layer 15 ... MR element layer 16 ... Second electrode film 16a, 16b ... Electrode layer 17 ... Insulating layer 18 ... Upper shield layer 19 ... Sliding surface 20 ... First Metal film

Claims (2)

[Claims] 1. A method of manufacturing a magnetoresistive effect magnetic head in which a pair of electrode layers are provided on a magnetoresistive effect element layer at a distance corresponding to a track width, the method comprising: A step of forming a first metal film so as to cover at least the region having the track width, and a second step of forming the electrode layer above the magnetoresistive element layer on which the first metal film is formed. A step of forming a metal film, and a region of the track width of the second metal film,
Forming the pair of electrode layers by removing the remaining metal film so that the metal film remains. 2. A magnetoresistive effect magnetic head for converting a magnetic signal within a track width into an electrical signal by using a magnetoresistive effect, comprising at least a magnetoresistive effect element layer and the magnetoresistive effect element layer. A first metal film formed so as to cover the region having the track width, and an electrode layer provided for flowing a signal detection current through the resistance effect element layer, the first metal film being formed. And forming a second metal film above the magnetoresistive element layer,
The second metal film is formed by removing a region of the track width of the first metal film so that the first metal film remains.
And a pair of electrode layers made of the metal film of claim 1.