JP2001101623A - Magnet-resistive magnetic head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a magnetic shielding film with high accuracy and to improve the yield. SOLUTION: This manufacturing method of a magneto-resistive magnetic head which is formed by arranging a magneto-resistance effect element between a pair of magnetic shielding film comprises a stage of forming a resist film which has an opening part corresponding to the shape of the magnetic shielding film, and whose lower layer end part is retreated from the upper layer end part on the opening part when the magnetic shielding film is formed, a stage of forming the magnetic shielding film by using the resist film and a stage of removing the resist film from on the formation surface together with the magnetic shielding film deposited on the resist layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-resistance effect type magnetic head for reading a signal recorded on a magnetic recording medium by utilizing a magneto-resistance effect and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, magnetoresistive elements (hereinafter referred to as M
It is called an R element. 2. Description of the Related Art A magneto-resistive magnetic head (hereinafter, referred to as an MR head) that reads a signal recorded on a magnetic recording medium by utilizing the magneto-resistive effect is widely used.

[0003] An MR element is a type of resistance element, and its electric resistance changes according to a change in an external magnetic field such as a signal magnetic field recorded on a magnetic recording medium. The MR head reads a signal recorded on a magnetic recording medium by utilizing the fact that a current flows through the MR element and the value of the current flowing through the MR element changes according to a signal magnetic field from the magnetic recording medium.

An MR head differs from a general magnetic induction type magnetic head, that is, a magnetic head in which a magnetic core is provided with a winding, in that a reproduction output does not depend on a relative speed with respect to a magnetic recording medium. Therefore, the MR head can obtain a sufficient output even in a system having a low relative speed, and in order to realize further higher density recording in the future,
It is considered to be an essential device.

As such an MR head, a so-called shield type MR head in which an MR element is provided between a pair of magnetic shield members has been put into practical use. This shield type MR head has characteristics that it has better frequency characteristics and higher reading resolution than a non-shield type MR head in which an MR element is provided between a pair of non-magnetic members. . Further, the shield type MR head guides the magnetic flux from the recording medium to the MR element, and as compared with a so-called yoke type MR head in which the MR element is a non-exposed type,
It has features that it is easy to manufacture and that a high reproduction output can be obtained.

[0006]

By the way, as the above-mentioned shield type MR head, a so-called thin film shield type MR head 100 as shown in FIGS. 41 and 42 is used.
It has been known. The MR head 100 has a structure in which a pair of magnetic shields are formed by soft magnetic thin films 101 and 102, and the pair of soft magnetic thin films 101 and 102 sandwich an MR element 104 via a gap layer 103.

As shown in FIG. 41, the MR head 100 has a pair of substrates 10 each having a cylindrical medium sliding surface.
5, 106, which are cut out as individual head chips and used as a magnetic head element for reading out an information signal while sliding on a magnetic tape, such as a tape streamer system.

FIG. 41 shows an individual MR head 100.
42 is a perspective view showing a state of a so-called head block before being cut out as FIG. 42. FIG. 42 is an enlarged view of a surrounding portion C shown in FIG. 41, and a portion serving as a medium sliding surface of the MR head 100. FIG.

By the way, a thin film shield type MR head 1
00, a soft magnetic thin film 101 serving as a magnetic shield,
After forming a soft magnetic thin film by a sputtering method, a resist film is formed on the soft magnetic film.
This is performed by using a photolithography technique to leave a portion of the resist film that will become a magnetic shield, and using the resist film as a mask to remove the soft magnetic film in the portion without the resist film by ion etching. Since the surface of the resist film subjected to the ion etching is a carbonized layer, the carbonized layer is removed by performing O ₂ plasma, and then the resist film is peeled off with a solvent such as acetone.

Here, the thin film shield type MR head 10
0, the soft magnetic films 101 and 10 serving as magnetic shields
2 must correspond to all wavelengths used in the tape streamer system as described above, and usually requires a film thickness of at least twice the longest wavelength and about 2 to 3 μm.

It is desirable that the ion etching rate for the soft magnetic films 101 and 102 be high, but the increase in the ion etching rate leads to an increase in the amount of heat. However, the selectivity between the resist film and the soft magnetic film becomes a problem. For this reason, the rate of ion etching cannot be generally increased with respect to the soft magnetic films 101 and 102. The thicker the soft magnetic films 101 and 102, the longer the time spent for ion etching. .

Since the soft magnetic films 101 and 102 are removed by ion etching and the resist film is also etched at the same time, the shape of the resist film is deformed and the soft magnetic film serving as a magnetic shield is formed. 101,
The edge portions 101a and 102a of 102 are formed with a gentle inclination.

In the ion etching, since the distribution of the etching rate is different in the plane on which the soft magnetic film is formed, it is difficult to control the thickness of the soft magnetic film in this plane, and the yield is greatly increased. In some cases, a significant decrease was caused.

When a laminated film in which a soft magnetic film and a non-magnetic film are alternately formed is provided as a magnetic shield, this laminated film is subjected to ion etching when the laminated film is subjected to ion etching. Since the end of the film is not magnetostatically coupled, it causes noise and cannot obtain good magnetic shield characteristics.

In view of the foregoing, the present invention has been proposed in view of the above-mentioned circumstances, and it is possible to form a magnetic shield film with high precision, to manufacture easily, to improve yield, and to improve reliability. And a method of manufacturing the same.

[0016]

According to the present invention, there is provided a magneto-resistance effect type magnetic head in which a magneto-resistance effect element is disposed between a pair of upper and lower magnetic shield films. The magnetic shield film is formed in a predetermined shape by a lift-off method, and has an edge portion formed substantially vertically.

As described above, in the magneto-resistance effect type magnetic head according to the present invention, since the magnetic shield film is formed in a predetermined shape by the lift-off method, and the edge portion is formed substantially vertically, the noise is reduced. And magnetic shield characteristics such as frequency characteristics and reading resolution can be improved.

According to another aspect of the present invention, there is provided a method of manufacturing a magnetoresistive magnetic head in which a magnetoresistive element is disposed between a pair of magnetic shield films. A step of forming a resist film having an opening corresponding to the shape of the magnetic shield film when forming the magnetic shield film, and forming a resist film in which the lower layer end is recessed from the upper layer end in the opening. A step of forming a magnetic shield film using the film; and a step of removing the resist film together with the magnetic shield film deposited on the resist film.

As described above, in the method of manufacturing a magneto-resistance effect type magnetic head according to the present invention, each of the pair of magnetic shield films has an opening corresponding to the shape of the magnetic shield film, and the lower layer is formed in the opening. Since the end portion is formed by a lift-off method using a resist film recessed from the upper layer end portion, the edge portion of the magnetic shield film can be formed substantially vertically, and the manufacturing process is greatly simplified. Can be.

[0020]

Embodiments of the present invention will be described below in detail with reference to the drawings.

First, an example of the configuration of a magnetoresistive magnetic head (hereinafter referred to as an MR head) to which the present invention is applied is shown in FIGS.

This MR head 1 has, as shown in FIG.
For example, it is a thin film shield type MR head which is mounted on the rotating drum 2 and reproduces a tape-shaped magnetic recording medium 3 by a helical scan method. As shown in FIGS. 2 to 4, the MR head 1 has a first substrate 4, a first soft magnetic film 5 formed on the first substrate 4, and a first soft magnetic film. A magnetoresistive effect element (hereinafter, referred to as an MR element) 7 formed on a first nonmagnetic insulating film 6 via a first nonmagnetic insulating film 6;
A second soft magnetic film 9 formed on the MR element 7 with a second non-magnetic insulating film 8 interposed therebetween, and a second soft magnetic film 9 formed on the second soft magnetic film 9 with a protective film 10 interposed therebetween. And a substrate 11.

FIG. 2 is a perspective view showing the structure of the MR head 1, and FIG. 3 is a transparent side view showing the structure of the MR head 1. FIG. 4 is an enlarged schematic plan view showing a portion of the MR head 1 serving as a medium sliding surface.

The first substrate 4 and the second substrate 11 correspond to FIG.
As shown in FIG. 3 and FIG. 3, the planar shape is formed in a substantially rectangular thin plate shape, and an upper end surface thereof is a medium sliding surface 1a that slides on the magnetic recording medium. The medium sliding surface 1a is an arcuate curved surface having a predetermined curvature.

The electrical resistance of the MR element 7 changes in accordance with the change in the angle between the direction of the current flowing through the MR element 7 and the direction magnetized by the magnetic field from the magnetic recording medium 3. In other words, the MR element 7 detects a signal from the magnetic recording medium 3 by a magnetoresistance effect. That is, the MR head 1 is
By detecting the change in the resistance value of the magnetic recording medium 3,
To read the signal recorded in the.

At both ends of the MR element 7 in the long side direction, FIG.
As shown in FIG. 2, a pair of permanent magnet films 12 for shortening the magnetic domains of the MR element 7 is provided. Further, at a position adjacent to the permanent magnet film 12, a pair of resistance reducing films 13 for reducing the resistance value of the MR element 7 and a portion electrically connected to the MR element 7 are provided. .

Further, the MR head 1 has the structure shown in FIGS.
As shown in (1), a pair of conductors 14 for supplying a current to the MR element 7 are provided with one ends connected to a pair of permanent magnet films 12, respectively. An external connection terminal 15 connected to an external circuit is provided on the other end of the pair of conductors 14.

In this MR head 1, the first soft magnetic film 5 and the second soft magnetic film 9 form a pair of magnetic shields, and a first non-magnetic shield between the pair of magnetic shields, which forms a shield gap. A magnetic insulating film 6 and a second non-magnetic insulating film 8 are provided. That is, in the MR head 1, a pair of magnetic shields is constituted by the first soft magnetic film 5 and the second soft magnetic film 9, and the first soft magnetic film 5 and the second soft magnetic film 9 The structure is such that the MR element 7 is interposed between the first non-magnetic insulating film 6 and the second non-magnetic insulating film 8 serving as a shield gap.

In this MR head 1, the first
The soft magnetic film 5 and the second soft magnetic film 9 are precisely formed in a predetermined shape by a lift-off method described in detail later. Edge portions 5a and 9a are formed substantially vertically.

In the MR head 1, the gap between the first soft magnetic film 5 and the second soft magnetic film 9 with respect to the MR element 7 is a so-called gap length.

In the MR head 1, instead of the first soft magnetic film 5 and the second soft magnetic film 9 serving as a magnetic shield, a soft magnetic thin film 20a as shown in FIG. A laminated film 20 formed by alternately forming the magnetic thin films 20b may be provided.

In the above-described MR head 1, FIGS. 1 to 5 show M
Although the R element 7 is illustrated in an enlarged manner, in actuality, the MR element 7 is much finer than the first substrate 2 and the second substrate 11. The length of the first substrate 2 in the direction in which the magnetic recording medium 3 runs is, for example, about 0.8 mm.
The length of the element 7 in the direction in which the magnetic recording medium 3 runs is, for example, about 5 μm. Therefore, this MR head 1
, The medium sliding surface 1 a is almost only the upper end surfaces of the first substrate 2 and the second substrate 11.

In the MR head 1 configured as described above, as shown in FIG.
The soft magnetic film 5 and the second soft magnetic film 9 are
Out of the signal field from the MR element 7
It works so that it is not pulled into. That is, in the MR head 1, the magnetic field outside the reproduction target relative to the MR element 7 is guided to the first soft magnetic film 5 and the second soft magnetic film 9, and only the reproduction target magnetic field is transmitted to the MR element 7. I will

In the MR head 1, the first soft magnetic film 5 and the second soft magnetic film 9 are precisely formed in a predetermined shape by a lift-off method described in detail later.
Edge portions 5a, 9a of the first soft magnetic film 5 and the second soft magnetic film 9 are formed substantially vertically.

Therefore, in the MR head 1 having such a structure, the magnetic shield characteristics such as frequency characteristics and reading resolution can be greatly improved.

In the MR head 1, instead of the first soft magnetic film 5 and the second soft magnetic film 9, a soft magnetic film 20a and a non-magnetic film 20b as shown in FIG. Are used alternately, the magnetic thin films 20a constituting the stacked film 20 are magnetostatically coupled to each other at the ends, and
It is possible to prevent a domain wall from occurring in a.

Accordingly, in the MR head 1, the domain wall of each magnetic thin film 20 a does not suddenly move upon receiving the signal magnetic field from the magnetic recording medium 3, and the movement of the domain wall is applied to the MR element 7. It can be prevented from being reproduced as a noise signal.

Next, a method of manufacturing the MR head 1 according to the present invention will be described.

The drawings used in the following description are similar to those shown in FIGS.
The characteristic portion may be shown in an enlarged manner, and the ratio of the dimensions of each member is not always the same as the actual one. Further, in the following description, specific examples of members constituting the MR head 1 and their materials, sizes, thicknesses, and the like will be described, but the present invention is not limited to the following examples. For example, in the following description, an example using a so-called shield-type SAL (Soft Adjacent Layer) bias type MR element having a structure similar to that practically used in a hard disk device or the like will be described. ,
It is not limited to this example.

When manufacturing the MR head 1, first,
As shown in FIGS. 6 and 7, a disk-shaped substrate member 30 of, for example, about 4 inches is prepared, and the surface of the substrate member 30 is subjected to mirror polishing. This substrate member 30 finally becomes the first substrate 4 of the MR head, and is made of a soft magnetic material having high hardness. In particular,
For example, Al ₂ O ₃ —TiC (Altic), α-Fe ₂ O ₃
(Α-hematite), Ni—Zn ferrite and the like are preferable. FIG. 7 is a sectional view taken along line X ₁ -X ₁ ′ shown in FIG.

Next, as shown in FIGS. 8 and 9, a first soft magnetic film 5 serving as a magnetic shield is formed on the substrate member 30. FIG. 9 is a sectional view taken along line X ₂ -X ₂ ′ shown in FIG.

The first soft magnetic film 5 is formed in a predetermined shape by a so-called lift-off method. That is, first, as shown in FIG. 10, a resist film 31 having an opening 31 a corresponding to the shape of the first soft magnetic film 5 is formed on the main surface of the substrate member 30. At this time, the resist film 31
In the opening 31a, it is preferable that the lower layer end is of an inverted tapered type in which the lower end is recessed from the upper end.

When the opening 31a of the resist film 31 is of a reverse taper type, a resist material for reverse taper, for example, ZPN-1100 (manufactured by Zeon Corporation),
Using AZ5214E (manufactured by Client) or the like, pre-baking and exposure are performed in the same manner as a normal resist film.
It can be formed by performing reversal baking by heating at a temperature of 110 ° C. and performing excessive exposure (reversal exposure).
When forming the reverse tapered resist film 31,
What is necessary is just to carry out by the method recommended for every reverse taper resist material mentioned above.

When the first soft magnetic thin film 5 is formed, an inversely tapered resist film 31 as shown in FIG.
Instead, a resist film 32 having a two-layer structure as shown in FIG. 11 may be formed on the substrate member 30.

The resist film 32 is formed by sequentially laminating a first resist layer 32a and a second resist layer 32b, has an opening 32c corresponding to the shape of the first soft magnetic film 5, and has an opening 32c. In the opening 32c, the first resist layer 32a has a shape recessed from the second resist layer 32b formed thereon.

When the resist film 32 having this two-layer structure is formed, a material for a normal antireflection film, for example, ARC (Brewer Science) is used as the first resist layer 32a.
The first resist layer 32a is formed over the entire surface of the substrate member 30 by using the first resist layer 32a. In addition, as the second resist layer 32b, a normal resist material, for example, AZ61
08 (manufactured by Client Corporation), the second resist layer 32b is formed on the first resist layer 32a so as to have an opening at a portion where the first soft magnetic film 5 is to be formed.
Then, after performing prebaking and exposure in the same manner as a normal resist film, development is performed for a longer time than usual.
As a result, the resist film 32 becomes the second resist layer 32
b, the first resist layer 32a exposed from the opening is removed, and the opening 32c has a shape in which the first resist layer 32a is recessed from the second resist layer 32b formed thereon. Become.

Next, using such a resist film 31 or 32, a first soft magnetic film 5 is formed by sputtering or the like. The material of the first soft magnetic film 5 is, for example, FeAlSi (Sendust) or any other material that exhibits good soft magnetism and is excellent in wear and corrosion.
There is no particular limitation. Also, the first soft magnetic film 5
Must correspond to all wavelengths used in the system in order to function as a magnetic shield for the MR head 1,
Usually, a film thickness of twice or more the longest wavelength is required. Here, Sendust is used as the first soft magnetic film 5, the thickness is 2.5 μm, and the size t ₁ × t ₂ is 80 μm × 100 μm.
And

Next, the resist film 31 or the resist film 32
Is removed together with the first soft magnetic thin film 5 deposited on the resist film 31 or the resist film 32. To remove the resist film 31 or the resist film 32, acetone or N
A solvent such as MP (N-methylpyrrolidone) can be used.

As a result, the first soft magnetic film 5 having a predetermined shape as shown in FIGS. 8 and 9 and having the edge portion 5a substantially vertical is formed on the substrate member 30.

As described above, the resist film 31 or the resist film 32 is removed together with the first soft magnetic film 5 deposited thereon, and only the portions not covered with the resist film 31 or the resist film 32 are covered with the first soft magnetic film 5. The method for forming the magnetic film 5 is generally called a lift-off method. In order to clearly separate the end of the first soft magnetic film 5 formed by the lift-off method, a reverse method as shown in FIG. Tapered resist film 31
Or a resist film 3 having a two-layer structure as shown in FIG.
2 is required.

Further, by stripping the resist film 31 or the resist film 32 while oscillating the substrate member 30 by the ultrasonic cleaning tank, the stripping time can be shortened.

In the case where a laminated film 20 in which soft magnetic films 20a and non-magnetic films 20b are alternately formed as shown in FIG. 5 is used instead of the first soft magnetic film 5 as a magnetic shield. In contrast to the conventional case where the predetermined shape is formed by ion etching, the end of the laminated film 20 is not magnetostatically coupled and does not cause noise.

Next, as shown in FIGS. 12 and 13, a non-magnetic insulating film 33 made of, for example, Al ₂ O ₃ is formed over the entire surface of the substrate member 30 on which the first soft magnetic film 5 is formed. After the film formation, polishing is performed until the first soft magnetic film 5 formed on the substrate member 30 is exposed. Thereby, the substrate member 3
The non-magnetic insulating film 33 is buried between the first soft magnetic film 5 and the first soft magnetic film 5, so that there is no step with the portion on the substrate member 30 where the first soft magnetic film 5 is not formed, and the surface is flattened.

The thickness t ₃ of the nonmagnetic insulating film 33 is
Since the soft magnetic film 5 needs to be completely buried, the first soft magnetic film 5 needs to have a thickness equal to or greater than the thickness of the first soft magnetic film 5. Here, the thickness t ₃ of the nonmagnetic insulating film 33 is set to 2 μm or more.
For example, the film was formed with a thickness of about 3 μm. The non-magnetic insulating film 33 may be made of SiO ₂ or the like instead of Al ₂ O ₃ , and is formed by an arbitrary method such as a sputtering method and a vapor deposition.

The surface on which the non-magnetic insulating film 33 is formed is roughly polished with diamond abrasive grains,
The surface may be conditioned by P (Chemical & Mechanical Polishing), or may be polished by CMP from the beginning. However, it is necessary to perform the process until the surface of the first soft magnetic film 5 is exposed over the entire surface of the substrate member 30.

Here, a heat treatment is performed on the first soft magnetic film 5. The heat treatment for the first soft magnetic film 5 is performed by the first heat treatment.
It is necessary to perform a heat treatment according to the material to be the soft magnetic film 5. Here, since the first soft magnetic film 5 is made of sendust, a heat treatment temperature of about 550 ° C. is required. For example, after heating to 550 ° C. in one hour, the heat treatment is performed for one hour at the same temperature. Hold, then allow to cool naturally.
Thereby, the first soft magnetic film 5 can obtain a magnetic permeability of about 800. FIG. 13 is a sectional view taken along the line X ₃ -X ₃ ′ shown in FIG.

Next, as shown in FIGS. 14 and 15, on the substrate member 30 on which the first soft film 5 is formed, a first non-magnetic insulating film 6 is formed by sputtering or the like. FIG. 15 is a cross-sectional view taken along the line X ₄ -X ₄ ′ shown in FIG.

As the material of the first non-magnetic insulating film 6, Al ₂ O ₃ is preferable from the viewpoints of insulation characteristics, wear resistance and the like. The thickness t ₄ of the first nonmagnetic insulating film 6 may be set to an appropriate value according to the frequency of a signal recorded on the magnetic recording medium 3. Here, the thickness t of the nonmagnetic insulating film is
₄ is, for example, about 100 nm.

Next, as shown in FIGS. 16 and 17, on the first nonmagnetic insulating film 6, a thin film constituting the SAL bias type MR element 7 (hereinafter, referred to as MR element thin film).
35 is formed by sputtering or the like. Note that FIG.
FIG. 17 is a sectional view taken along line X ₅ -X ₅ ′ shown in FIG.

The MR element thin film 35 includes, for example, a Ta layer having a thickness of about 5 nm as a lower layer, a NiFeNb layer having a thickness of about 32 nm as a SAL bias layer, and a Ta layer having a thickness of about 5 nm as an intermediate insulating layer. About 30n thickness as MR layer
An NiFe layer having a thickness of m and a Ta layer having a thickness of about 1 nm as an upper layer are formed by sequentially laminating in this order by sputtering or the like. In the MR element thin film 35, the NiFe layer is a soft magnetic film having a magnetoresistance effect, and serves as a magnetically sensitive portion of the MR element 7. In the MR element thin film 35, the NiFeNb layer is a so-called SAL film that applies a bias magnetic field to the NiFe layer.

The material of each layer constituting the MR element thin film 35 and the thickness thereof are not limited to the above examples, and an appropriate material may be selected according to the purpose of use of the MR head 1 and the like. What is necessary is just to set it to an appropriate film thickness.

Here, the thickness t ₄ of the first nonmagnetic insulating film 6 is t ₄ = G / 2−2, where G is the distance between shields (so-called read gap) finally required for the system.
(Film thickness of Ta layer: 5 nm + film thickness of NiFeNb layer: 32 nm)
+ Ta layer thickness 5 nm + NiFe layer thickness 30 nm /
It is determined by calculating 2). This gives M
The R element 7 is accurately arranged at the center between the pair of magnetic shields.

Next, as shown in FIGS.
In order to stabilize the operation of the R element 7, two rectangular permanent magnet films 12 are embedded in the MR element thin film 35 in a portion to be the MR element 7 by using a photolithography technique.

The permanent magnet film 12 has, for example, a length t ₅ in the long side direction of about 50 μm and a length t ₆ in the short side direction of about 10 μm.
And the thickness t ₇ between the two permanent magnet films is about 5 μm. The interval t ₇ between these two permanent magnet films finally becomes the track width of the MR element 7. That is, in the MR head 1, the track width of the MR element 7 is about 5 μm. Note that the track width of the MR element 7 is not limited to the above example, and the MR head 1
It may be set to an appropriate value according to the purpose of use of.

Then, the MR element 7 is provided on the permanent magnet film 12.
Further, in order to reduce the resistance value of a portion electrically connected to the MR element 7, a low-resistance film 13 having a low resistance value is formed.

The permanent magnet film 12 and the resistance reducing film 13
Is embedded in the MR element thin film 35, for example, first,
A mask having two rectangular openings in a portion to be the MR element 7 is formed using a photoresist. Next, by performing etching, the MR exposed from the opening is formed.
The element thin film 35 is removed. Note that the etching here may be a dry method or a wet method, but ion etching is preferable in consideration of ease of processing and the like.

Next, the permanent magnet film 12 is formed by sputtering or the like on the MR element thin film 35 on which the mask is formed. The material of the permanent magnet film 12 is preferably a material having a coercive force of 1000 [Oe] or more, such as CoNiPt or CoCrPt. Further, the film thickness of the permanent magnet film 12 was substantially the same as that of the MR element thin film 35.

Next, a low-resistance film 13 is formed on the permanent magnet film 12 by sputtering or the like. As a material of the low resistance film 13, for example, Cr, Ta, or the like is preferable. The thickness of the low resistance film 13 was about 60 nm.

Next, the photoresist serving as a mask is replaced with the permanent magnet film 12 formed on the photoresist.
And together with the low resistance film 13. As a result, the permanent magnet film 12 and the low resistance film 13 having predetermined shapes as shown in FIGS. 18 to 20 are embedded in the MR element thin film 35. FIG. 19 is an enlarged plan view showing the encircled portion A shown in FIG.
20 is a sectional view taken along line X ₆ -X ₆ ′ shown in FIG.

FIGS. 21 to 36 show the encircling portion A shown in FIG. 18 in an enlarged manner.

Next, as shown in FIGS. 21 and 22, a portion serving as an MR element 7 and a conductor 1 for supplying a sense current to the MR element 7 are formed by using a photolithography technique.
A mask having an opening in a portion to be 4 is formed. Then, etching is performed to remove the MR element thin film 35 exposed in the opening. Note that the etching here may be a dry method or a wet method, but ion etching is preferable in consideration of ease of processing and the like. Then, by removing the photoresist used as the mask, the portion 35a to be the MR element 7 and the portion 35b to be the conductor portion 14 in the MR element thin film 35 are left.

The width of the portion 35a to be the MR element 7,
That is, the width t ₈ of the MR element 7 and the portion 3 to be the conductor portion 14
The length t ₉ and the width t _{10 of} the 5b and the interval t ₁₁ between the portions 35b to be the pair of conductors 14 may be set to optimal values according to the environment used by the MR head 1. Here, the width t ₈ of the MR element 7 is set to about 4 μm. This MR
Width t ₈ of the element 7, the length from the end of the medium sliding surface 1a to the other end, i.e. corresponding to the depth length. Therefore, M
The depth of the R element 7 is about 4 μm.

In this case, the portion 3 to be the conductor portion 14
The length t ₉ of each of the 5b is about 2 mm, the width t ₁₀ thereof is about 80 μm, and the interval t ₁₁ thereof is about 40 μm.
μm. FIG. 22 shows a line segment X ₇ shown in FIG.
It is a cross-sectional view taken along -X ₇ '.

Next, as shown in FIGS. 23 and 24, the conductor portion 14 is formed by using a photolithography technique. FIG. 24 is a sectional view taken along line X ₈ -X ₈ ′ shown in FIG.

Specifically, first, a mask having an opening in a portion 35b to be the conductor portion 14 is formed by photoresist. Next, the portion exposed to the opening by performing etching, that is, the portion 35b to be the conductor portion 14 is formed.
The MR element thin film 35 remaining in the step is removed. next,
A conductive film is formed thereon while the photoresist mask is left as it is. Here, the conductive film has, for example, a thickness of 1
0 nm Ti film, 90 nm film thickness, 10 nm film thickness
Are sequentially laminated by sputtering or the like in this order. Thereafter, the photoresist serving as a mask is removed together with the conductive film formed on the photoresist, so that the conductor portion 14 is formed.

Next, as shown in FIGS. 25 and 26, a second non-magnetic insulating film 8 is formed by sputtering or the like. FIG. 26 is a sectional view taken along line X ₉ -X ₉ ′ shown in FIG.

As the material of the second non-magnetic insulating film 8, Al ₂ O ₃ is preferable from the viewpoints of insulation characteristics, wear resistance and the like. The thickness t ₁₂ of the second non-magnetic insulating film 8 is
It may be set to an appropriate value according to the frequency of the signal recorded on the magnetic recording medium and the like, and here, it is set to 120 nm.

The thickness t of the second non-magnetic insulating film 8
₁₂ , when the distance between shields (so-called reproduction gap) finally required for the system is G, t ₁₂ = G / 2−
(NiFe layer thickness 30 nm / 2 + Ta layer thickness 1 n
m) is determined. This gives M
The R element 7 is accurately arranged at the center between the pair of magnetic shields.

Next, as shown in FIGS. 27 and 28, a second soft magnetic film 9 serving as a magnetic shield is formed on the second non-magnetic insulating film 8. FIG. 28 is a sectional view taken along the line X ₁₀ -X ₁₀ ′ shown in FIG.

The first soft magnetic thin film 9 is formed in a predetermined shape by a so-called lift-off method. That is, first, as shown in FIGS. 29 and 30, on the main surface of the second nonmagnetic insulating film 8, a resist film 36 having an opening 36a at a portion where the second soft magnetic film 9 is formed is formed. To form
FIG. 30 is a sectional view taken along line X ₁₁ -X ₁₁ ′ shown in FIG.

At this time, the resist film 36 is
In (a), it is preferable that the lower layer portion has an inverted tapered shape in which an end portion is recessed from an upper layer end portion.

When the end portion 36a of the resist film 36 is of a reverse taper type, a resist material for reverse taper is used.
For example, ZPN-1100 (manufactured by Zeon Corporation), AZ
After pre-baking and exposing using a 5214E (manufactured by Client) in the same manner as a normal resist film,
It can be formed by performing reversal baking by heating at a temperature of 0 ° C. and performing excessive exposure (reversal exposure). When forming the reverse tapered resist film 36, a method recommended for each of the above-described reverse tapered resist materials may be used.

When the second soft magnetic thin film 9 is formed, a two-layer structure as shown in FIGS. 31 and 32 is used instead of the inversely tapered resist film 36 as shown in FIGS. 29 and 30. May be formed on the first nonmagnetic insulating film 8. FIG. 32 is a cross-sectional view taken along line X ₁₂ -X ₁₂ ′ shown in FIG.

In this case, the resist film 37 is formed by sequentially laminating a first resist layer 37a and a second resist layer 37b, and has an opening at a portion where the second soft magnetic film 9 is formed. In this opening 37c, the first resist layer 37a has a shape recessed from the second resist layer 37b formed thereon.

When the resist film 37 having the two-layer structure is formed, a material for an ordinary antireflection film, for example, ARC (Brewer Science) is used as the first resist layer 37a.
The first resist layer 37a is formed over the entire surface of the second non-magnetic insulating film 8 by using the same method. As the second resist layer 37b, a normal resist material, for example, AZ6108 (manufactured by Client Corporation) is used, and the second resist layer 37b is formed on the first resist layer 37a by the second resist layer 37b.
Is formed so as to have an opening at a portion where the soft magnetic film 9 is formed. Then, after performing prebaking and exposure in the same manner as a normal resist film, development is performed for a longer time than usual. As a result, the resist film 37 is exposed from the opening of the second resist layer 37b.
a is removed, and in this opening 37c,
The first resist layer 37a has a shape recessed from the second resist layer 37b formed thereon.

Next, using the resist film 36 or the resist film 37, a second soft magnetic film 9 is formed by sputtering or the like. As the material of the second soft magnetic film 9, since the MR element 7 has already been formed, the heat treatment at a high temperature performed on the first soft magnetic film 5 cannot be performed. There are naturally restrictions. For this reason, as the second soft magnetic film 9, a material exhibiting soft magnetism by performing a heat treatment at 350 ° C. or less, which is the heat-resistant temperature of the MR element 7, or a material exhibiting soft magnetism without performing the heat treatment is used. Is preferred. Further, the second soft magnetic film 9 is made of M
In order to function as a magnetic shield for the R head 1, it must be compatible with all wavelengths used in the system, and usually requires a film thickness twice or more the longest wavelength. Here, the second
The soft magnetic film 9 is made of a Co-based amorphous material and has a thickness of 2.5 μm and a size t ₁₃ × t ₁₄ of 80 μm ×
The thickness was 100 μm.

Next, the resist film 36 or the resist film 37
Is removed together with the second soft magnetic thin film 9 deposited on the resist film 36 or the resist film 37. For removing the resist film 36 or the resist film 37, acetone or
A solvent such as NMP (N-methylpyrrolidone) can be used.

As a result, on the second non-magnetic insulating film 8,
A second soft magnetic film 9 having a predetermined shape as shown in FIGS. 27 and 28 and having an edge portion 9a substantially vertical is formed.

As described above, in order to clearly separate the end of the second soft magnetic film 9 formed by the lift-off method, the resist film 36 having the reverse taper as shown in FIGS. A resist film 37 having a two-layer structure as shown in FIGS. 31 and 32 is required.

Further, the stripping time can be reduced by stripping the resist film 36 or the resist film 37 while oscillating the substrate member 30 in the ultrasonic cleaning tank.

Also, a case where a laminated film 20 in which soft magnetic films 20a and non-magnetic films 20b are alternately formed as shown in FIG. 5 is used as the magnetic shield instead of the second soft magnetic film 9. In contrast to the conventional case where the predetermined shape is formed by ion etching, the end of the laminated film 20 is not magnetostatically coupled and does not cause noise.

Next, as shown in FIGS. 33 and 34, a conductor to be the external connection terminal 15 of the MR head 1 is formed on the end of the conductor portion 14 by using the photolithography technique. FIG. 34 shows a line segment X ₁₃ − shown in FIG.
It is a cross section by X ₁₃ ′.

Specifically, for example, first, a mask having an opening in a portion to be the external connection terminal 15 is formed by using a photoresist. Next, by performing etching, the portion of the second non-magnetic insulating film 8 exposed at the opening, that is, the portion serving as the external connection terminal 15 is removed to expose the ends of the conductor portions 14. Let it. Next, a conductive film is formed with the photoresist mask left as it is. Here, the conductive film is formed by, for example, electrolytic plating using a copper sulfate solution so that Cu has a thickness of about 6 μm. The conductive film may be formed by a method other than the electrolytic plating as long as it does not affect other films. Thereafter, the photoresist serving as the mask is removed together with the conductive film formed on the photoresist. Thereby, the external connection terminal 15 is formed on the end of the conductor portion 14.

The length t ₁₅ of the external connection terminal ₁₅
Is formed, for example, as about 50 μm. The width t ₁₆ of the external connection terminal 15 is the same as the width t ₁₀ of the conductor portion 14, for example, about 80 μm.

Next, as shown in FIGS. 35 and 36, M
In order to block the entire R head 1 from the outside, a protective film 10 is formed on the entire surface. FIG. 36 is a sectional view taken along line X ₁₄ -X ₁₄ ′ shown in FIG.

Specifically, for example, Al ₂ O ₃ is formed to a thickness of about 4 μm by sputtering. As a material of the protective film 10, any material other than Al ₂ O ₃ can be used as long as it is a non-magnetic and non-conductive material.
In consideration of environmental resistance and wear resistance, Al ₂ O ₃ is preferable. The protective film 10 may be formed by a method other than sputtering, for example, by a vapor deposition method or the like.

Next, the protective film 10 formed on the entire surface is polished until the external connection terminals 15 are exposed on the surface. In this polishing step, for example, rough polishing is performed with diamond abrasive grains having a particle size of about 2 μm until the surface of the external connection terminal 15 is exposed. Then, buffing is performed with silicon abrasive grains to finish the surface to a mirror-like state.

As a result, a substrate member 30 on which a number of head elements that finally become the MR head 1 are formed is obtained.

Next, as shown in FIG.
Substrate member 30 on which a large number of head elements 40 are formed
Is cut into strips to form a head block 41 in which the head elements 40 are arranged in the horizontal direction. Here, the number of head elements 40 arranged in the horizontal direction is preferably as large as possible in consideration of productivity. In FIG. 37, for simplification, a head block 41 in which five head elements 40 are arranged
However, in practice, the head element 4
Zeros may be arranged. Further, in this embodiment, the width t ₁₇ of the head block 41 is set to 2 mm.

Next, as shown in FIG. 38, on the head block 41, a second substrate 11 of the MR head 1, for example, the thickness t ₁₈ is pasted guard member 42 of about 0.7 mm. Polycrystalline ferrite or the like is used for the guard member 42. In attaching the guard member 42,
For example, a resin-based adhesive or the like is used. At this time, the height t19 of the guard member 42 is made lower than the height of the head block 41, and the external connection terminals 15 formed on the head block 41 are exposed to the outside. Thus, the external connection terminal 15 can be electrically connected to the outside.

Next, as shown in FIG.
The surface to be the medium sliding surface 1a is subjected to cylindrical polishing, and this surface is formed in an arc shape. Specifically, the front end of the MR element 7 is exposed on the medium sliding surface 1a,
Cylindrical polishing is performed until the depth of the element 7 reaches a predetermined length. Thereby, the MR head 1 as shown in FIG.
The surface serving as the medium sliding surface 1a is an arcuate curved surface. The medium sliding surface 1 formed by this cylindrical polishing process
The curved surface shape of the surface a may be an optimal shape according to the tape tension or the like, and is not particularly limited.

Next, as shown in FIG.
2 is joined to each head element 40.
Each time, it is divided along a cutting line BB ′ corresponding to the azimuth angle θ required by the system. Thereby, many individual MR heads 1 as shown in FIG. 2 are obtained.

When using the MR head 1 manufactured as described above, the MR head 1 is attached to the chip base, and the external connection terminals 15 are electrically connected to the terminals provided on the chip base. You. And this MR
The head 1 is shown in FIG.
And is used as a magnetic head for reproduction.

As described above, in the present method, the first soft magnetic film 5 and the second soft magnetic film 9 serving as a pair of magnetic shields are
The above-described reverse taper type resist film 31, 36 or 2
Like the resist films 32 and 37 having a layer structure, the resist film has an opening corresponding to the shape of the magnetic shield film, and the lower end of the opening is recessed from the upper end in the opening by a lift-off method. Has formed. This allows
According to this method, the first soft magnetic film 5 and the second soft magnetic film 9 serving as the magnetic shield can be formed in a predetermined shape with high precision. Membrane 9
Can be formed substantially vertically.

Therefore, in the MR head 1 manufactured as described above, the magnetic shield characteristics such as frequency characteristics and reading resolution can be greatly improved.

In this method, instead of the first soft magnetic film 5 and the second soft magnetic film 9 as a pair of magnetic shields, a soft magnetic film 20a and a non-magnetic film 20b as shown in FIG.
Is formed alternately, the laminated film 20 is formed,
The magnetic thin films 20a constituting the laminated film 20 are mutually magnetostatically coupled to each other at the ends, thereby preventing a magnetic domain wall from being formed in each magnetic thin film 20a.

Therefore, the MR head 1 manufactured as described above receives a signal magnetic field from the magnetic recording medium 3 and
It is possible to prevent the domain wall of each magnetic thin film 20a from suddenly moving and prevent the movement of the domain wall from being applied to the MR element 7 and reproduced as a noise signal.

Further, in this method, the track marker is determined with reference to the edge portion 5a of the first soft magnetic film 5 and the edge portion 9a of the second soft magnetic film 9 which are a pair of magnetic shields formed substantially vertically. Can also be adjusted.

Further, in the present method, unlike the conventional case where a predetermined shape is formed by ion etching, there is no variation in the film thickness distribution due to ion etching, and the productivity is greatly improved. And the number of steps can be greatly simplified.

[0110]

As described in detail above, according to the present invention, each of the pair of magnetic shield films has an opening corresponding to the shape of the magnetic shield film, and the lower end portion of the opening has an upper layer. Since the magnetic shield film is formed by the lift-off method using the resist film recessed from the end, the edge portion of the magnetic shield film can be formed substantially vertically, and the manufacturing process can be greatly simplified. Then, in the magnetoresistive head manufactured as described above, generation of noise and the like can be suppressed, and good magnetic shield characteristics can be obtained.

Therefore, according to the present invention, a high-quality magnetoresistive head can be manufactured easily and in large quantities, and the productivity can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which an MR head 1 to which the present invention is applied is mounted on a rotating drum.

FIG. 2 is a perspective view showing the configuration of the MR head.

FIG. 3 is a perspective side view showing a configuration of the MR head.

FIG. 4 is an enlarged schematic plan view showing a portion serving as a medium sliding surface of the MR head.

FIG. 5 is a cross-sectional view of a principal part showing a configuration of a laminated film serving as a magnetic shield of the MR head.

FIG. 6 is a diagram illustrating a manufacturing process of the MR head.
FIG. 3 is a plan view showing a substrate member serving as a first substrate.

FIG. 7 is a diagram illustrating a manufacturing process of the MR head.
FIG. 7 is a sectional view taken along line X ₁ -X ₁ ′ shown in FIG. 6.

FIG. 8 is a diagram illustrating a manufacturing process of the MR head.
FIG. 4 is a plan view showing a state where a first soft magnetic film is formed on a substrate member.

FIG. 9 is a diagram illustrating a manufacturing process of the MR head.
FIG. 9 is a sectional view taken along line X ₂ -X ₂ ′ shown in FIG. 8.

FIG. 10 is a view for explaining a manufacturing process of the MR head, and is a cross-sectional view of a principal part showing a state where an inversely tapered resist film is formed on a substrate member.

FIG. 11 is a view illustrating a manufacturing process of the MR head, and is a cross-sectional view of a main part showing a state where a resist film having a two-layer structure is formed on a substrate member;

FIG. 12 is a diagram for explaining a manufacturing process of the MR head, and is a plan view showing a state in which a non-magnetic insulating film is embedded between a substrate member and a first soft magnetic film.

FIG. 13 is a view for explaining a manufacturing process of the MR head, and is a cross-sectional view along line X ₃ -X ₃ '4 shown in FIG.

FIG. 14 is a diagram for explaining a manufacturing process of the MR head, and is a plan view showing a state in which a first nonmagnetic insulating film is formed on a first substrate member on which a first soft magnetic film is formed. It is.

FIG. 15 is a diagram illustrating a manufacturing process of the MR head, and is a cross-sectional view taken along line X ₄ -X ₄ ′ shown in FIG.

FIG. 16 is a diagram for explaining a manufacturing process of the MR head, and is a plan view showing a state in which a thin film for an MR element is formed on a first non-magnetic insulating film.

FIG. 17 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₅ -X ₅ ′ shown in FIG. 16;

FIG. 18 is a diagram illustrating a manufacturing process of the MR head, and is a plan view showing a state where a pair of permanent magnet films and a low-resistance film are formed.

FIG. 19 is a diagram for explaining a manufacturing process of the MR head, and is an enlarged plan view showing a surrounding portion A shown in FIG. 18;

FIG. 20 is a diagram illustrating a manufacturing process of the MR head, and is a cross-sectional view taken along line X ₆ -X ₆ ′ shown in FIG.

FIG. 21 is a diagram for explaining a manufacturing process of the MR head, and illustrates M and M other than a portion serving as an MR element and a portion serving as a conductor.
It is a top view showing the state where the thin film for R elements was removed.

FIG. 22 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₇ -X ₇ ′ shown in FIG. 21;

FIG. 23 is a diagram illustrating a manufacturing process of the MR head, and is a plan view illustrating a state where a conductor is formed.

FIG. 24 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₈ -X ₈ ′ shown in FIG. 23;

FIG. 25 is a diagram for explaining the manufacturing process of the MR head, and is a plan view showing a state where a second non-magnetic insulating film is formed.

FIG. 26 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₉ -X ₉ ′ shown in FIG. 25;

FIG. 27 is a diagram illustrating a manufacturing process of the MR head, and is a plan view showing a state in which a second soft magnetic film is formed on a second non-magnetic insulating film.

FIG. 28 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₁₀ -X ₁₀ ′ shown in FIG. 27;

FIG. 29 is a diagram illustrating a manufacturing process of the MR head, and is a main part plan view showing a state where a reverse-tapered resist film is formed on the second non-magnetic insulating film;

FIG. 30 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₁₁ -X ₁₁ ′ shown in FIG. 29;

FIG. 31 is a view illustrating a manufacturing step of the MR head, and is a main part plan view showing a state where a resist film having a two-layer structure is formed on a second non-magnetic insulating film;

FIG. 32 is a view for explaining the manufacturing process of the MR head, and is a cross-sectional view along line X ₁₂ -X ₁₂ ′ shown in FIG. 31;

FIG. 33 is a diagram for explaining the manufacturing process of the MR head, and is a plan view showing a state where external connection terminals are formed at the ends of the conductor.

FIG. 34 is a view illustrating a manufacturing process of the MR head, and is a cross-sectional view along line X ₁₃ -X ₁₃ ′ shown in FIG. 33;

FIG. 35 is a plan view showing a state in which a protective film is formed, without illustrating a manufacturing process of the MR head.

36 is a view illustrating a manufacturing process of the MR head, and is a cross-sectional view taken along the line X ₁₄ -X ₁₄ ′ shown in FIG. 35;

FIG. 37 is a diagram illustrating a manufacturing process of the MR head, and is a plan view illustrating a head block in which a number of head elements are cut so as to be arranged in a horizontal direction.

FIG. 38 is a view for explaining the manufacturing process of the MR head, and is a perspective view showing a state where a guard member is joined to the head block.

FIG. 39 is a view for explaining the manufacturing process of the MR head, and is a perspective view showing a state in which cylindrical polishing has been performed on a surface of the MR head to be a medium sliding surface.

FIG. 40 is a view for explaining a manufacturing process of the MR head.
FIG. 4 is a plan view showing a state of being divided into R heads.

FIG. 41 shows a state before cutting as individual MR heads.
FIG. 3 is a perspective view showing a state of a so-called head block.

FIG. 42 is an enlarged plan view of a surrounding portion C shown in FIG. 41, and is a schematic plan view showing a configuration of a conventional MR head.

[Explanation of symbols]

Reference Signs List 1 MR head, 4 first substrate, 5 first soft magnetic film, 6 first non-magnetic insulating film, 7 MR element, 8 second
Non-magnetic insulating film, 9 second soft magnetic film, 11 second substrate, 20 laminated film, 31, 36 reverse tapered resist film, resist film having 32,372 layer structure

Claims (6)

[Claims] 1. A magnetoresistive head having a magnetoresistive element disposed between a pair of magnetic shield films, wherein each of the pair of magnetic shield films is formed in a predetermined shape by a lift-off method. A magnetoresistive head having an edge portion formed substantially vertically. 2. The magneto-resistance effect type magnetic head according to claim 1, wherein said magnetic shield film is made of a soft magnetic film. 3. The magnetic shield film according to claim 1, wherein a soft magnetic film and a non-magnetic film are sequentially laminated.
The magnetoresistive effect type magnetic head according to the above. 4. A method of manufacturing a magneto-resistance effect type magnetic head in which a magneto-resistance effect element is disposed between a pair of magnetic shield films, wherein the magnetic shield film is formed in the shape of the magnetic shield film. A step of forming a resist film having a corresponding opening, wherein a lower layer end is recessed from an upper layer end in the opening; a step of forming a magnetic shield film using the resist film; and Removing the film together with the magnetic shield film deposited on the resist film. 5. The method according to claim 4, wherein the magnetic shield film is formed of a soft magnetic film. 6. The method according to claim 4, wherein the magnetic shield film is formed by sequentially laminating a soft magnetic film and a non-magnetic film.