JPH0721533A - Production of thin-film magnetic head - Google Patents

Abstract

PURPOSE:To improve yield, to increase a reproducing output and to prevent burning and discontinuity by stably forming a magneto-resistance effect element layer having a desirable characteristic. CONSTITUTION:A magneto-resistance effect film 10 is formed on a lower insulating layer 4, and a frame resist 11 fringing the outside of the magneto-resistance effect element layer to be obtained is formed on the film 10. A metallic plating film 12 is formed on the film 10 surface except on the resist 11, and the resist 11 and the plating film 12 inside the resist 11 is covered with a cover resist 13. Wet etching is applied under these conditions, and the film 12 outside the resists 13 and 11 is removed. The resists 13 and 11 are then removed, and the unnecessary part of the film 10 is removed by dry etching with the film 12 remaining under the resist 13 as a mask. The remaining film 12 is finally removed, and the magneto-resistance effect film 10 remaining after removal is used as a magneto-resistance effect element layer.

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 thin film magnetic head for reproducing recorded information on a magnetic recording medium such as a magnetic disk or a magnetic tape by utilizing the magnetoresistive effect. In other words, the present invention relates to a method of forming a magnetoresistive layer which is a main part of a magnetoresistive thin film magnetic head.

[0002]

2. Description of the Related Art In a magnetic recording device such as a magnetic disk device which is widely used as an external recording device for a computer, miniaturization and high density recording have been made in recent years.
On the side of a magnetic recording medium which is a recording medium, the recording track width and the linear recording width tend to become narrower. With this,
Even in a thin film magnetic head used as a recording / reproducing means, it is becoming difficult to reliably reproduce recorded information with a conventional inductive thin film magnetic head utilizing an electromagnetic induction phenomenon.
As a new reproducing means in place of the inductive type, a magnetoresistive effect (magnetoresistive effect), that is, a magnetoresistive thin film magnetic head utilizing the property that the electric resistance value of a ferromagnetic material increases or decreases according to the strength of the peripheral magnetic field is used. It is being used.

FIG. 6 is a front view of a magnetoresistive thin-film magnetic head, and FIG. 7 is a longitudinal sectional view showing the same use state. The magnetoresistive thin-film magnetic head has a pair of electrode layers 2 and 2 which are in contact with each other at a predetermined distance above the magnetoresistive element layer 1 formed of a ferromagnetic material having a magnetoresistive effect. An upper magnetic shield layer 5 which is laminated on both upper and lower sides with an upper insulating layer 3 and a lower insulating layer 4 interposed therebetween.
And the lower magnetic shield layer 6.

In the thin film magnetic head as described above, the lower magnetic shield layer 6, the lower insulating layer 4 and the magnetic layer are formed on one surface of the substrate 7, more specifically, on the undercoat film 8 formed on the one surface. The resistance effect element layer 1, the electrode layers 2 and 2, the upper insulating layer 3, and the upper magnetic shield layer 5 are laminated in this order, and the whole is covered with a protective film 9. The substrate 7 is shown in FIG.
As shown in FIG. 5, a slider that slightly floats on the recording surface A of the magnetic recording medium and relatively moves along the recording surface A is formed. Is performed on the rear end surface of the recording surface A in the relative movement direction.

The recording information magnetically recorded on the recording surface A is the electric resistance value of the magnetoresistive effect element layer 1 which is changed by the action of the magnetic field of each part of the moving recording surface A as described above, and is recorded between the electrode layers 2 and 2. It is regenerated by taking out the voltage output value of (1) as a medium. Since the magnetoresistive effect thin-film magnetic head is a read-only head, in general, a recording-only inductive head part is provided above each of the layers forming the read-only magnetoresistive effect head part. It is used as a composite type thin film magnetic head formed by stacking layers.

The upper magnetic shield layer 5 and the lower magnetic shield layer 6 are made of a soft magnetic material such as a permalloy (NiFe) type alloy, a cobalt type alloy, etc., and external magnetic noise propagating to the magnetoresistive effect element layer 1, especially, , Has a function of blocking a leakage magnetic field from an adjacent recording track and an adjacent recording bit, which correspond to the moving direction of the recording surface A, and lead magnetic shield layer (lower magnetic shield layer 6) and subsequent magnetic shield layer ( It may also be referred to as the upper magnetic shield layer 5). The upper insulating layer 3 and the lower insulating layer 4 are made of an insulating material such as alumina (Al ₂ O ₃ ) and silicon dioxide (SiO ₂ ), and are composed of upper and lower magnetic shield layers 5 and 5, which are conductors.
6 serves to prevent an electrical short circuit between the magnetoresistive effect element layer 1 and the magnetoresistive effect element layer 1.

In the magnetoresistive effect element layer 1 which is a main part of the magnetoresistive effect type thin film magnetic head, the side shown in FIG. 6 is the long side and the side shown in FIG. 7 is the short side on the upper surface of the lower insulating layer 4. The layers are formed in a rectangular plane shape having sides. 8 and 9 are explanatory views showing a conventional procedure for forming the magnetoresistive effect element layer 1, FIG. 8 is a front sectional view, and FIG. 9 is a plan view from above.

First, as shown in FIGS. 8 (a) and 9 (a), by a sputtering method or a vacuum deposition method in a uniform magnetic field,
A magnetoresistive film 20 having a thickness of about 50 nm is formed on the entire surface of the lower insulating layer 4. The magnetoresistive film 20
Is generally obtained by forming a single layer of a permalloy (NiFe) based soft magnetic alloy. The permalloy film and a cobalt based soft magnetic alloy for applying a bias magnetic field to the permalloy film. There is also a case where a three-layer structure of a bias film made of and a magnetic domain control film made of an antiferromagnetic material such as FeMn for controlling the magnetic domain of the permalloy film is used. The reason for forming the film in a magnetic field is to align the magnetization direction of the obtained magnetoresistive film 20 with the direction of the magnetic field and induce magnetic anisotropy.

Then, using a spin coater, a positive type photoresist is evenly applied to the surface of the magnetoresistive film 20 and baked, and a photomask having a predetermined exposure pattern is aligned with the photomask. After the exposure, development and baking are performed again to increase the adhesion strength. As a result, on the lower insulating layer 4, as shown in FIGS. 8B and 9B, the magnetoresistive effect element layer 1 to be obtained.
The resist 21 corresponding to the planar shape of is left.

Next, the magnetoresistive film 20 and the resist 21
Dry etching such as ion milling is carried out from above the resist, and as shown in FIGS. 8 (c) and 9 (c), the resist 21 is removed.
The magnetoresistive effect film 20 is removed except for the portion covered by. Finally, the resist 21 is removed using a resist stripping solution such as acetone. As a result, a resist is formed on the lower insulating layer 4 as shown in FIGS. 8 (d) and 9 (d).
The magnetoresistive effect film 20 covered with 21 remains as the magnetoresistive effect element layer 1.

Further, the electrode layers 2 and 2 are formed on the magnetoresistive effect element layer 1 formed as described above by the procedure shown in FIGS. 10 and 11. 10 is a front sectional view, and FIG. 11 is a plan view from above.

First, by a sputtering method or a vacuum deposition method,
An electrode film 22 made of a conductive material such as Cu, W, or Au is formed to a thickness of 200 to 500 nm on the entire surface of the lower insulating layer 4 including the formation portion of the magnetoresistive effect element layer 1, Then, a positive type photoresist is evenly applied to the surface of the electrode film 22 and, similarly to the case of forming the magnetoresistive effect element layer 1,
Pre-baking, exposure through a photomask, development, and post-baking are performed, and as shown in FIGS. 10 (a) and 11 (a), corresponding to the shapes of the electrode layers 2 and 2 to be obtained, the magnetoresistive effect element Resist 2 with some contact on both sides of layer 1
Leave 3, 23.

Next, the electrode film 22 is removed by wet etching using the remaining resists 23 and 23 as a mask, except for the portions covered with the resists 23 and 23, and finally, a resist stripping solution such as acetone is used. The above resist
Remove 23 and 23. As a result, on the lower insulating layer 4, the figure
As shown in FIG. 10 (b) and FIG. 11 (b), the electrode films 22 covered with the resists 23, 23 have a shape in which a part of each is in contact with both sides of the magnetoresistive effect element layer 1 in the longitudinal direction. It remains as the electrode layers 2 and 2. In the wet etching, it is necessary to select an etching solution that does not attack permalloy forming the magnetoresistive effect element layer 1.

[0014]

However, in the conventional magnetoresistive effect type thin film magnetic head provided with the magnetoresistive effect element layer 1 formed by the above procedure, the electrical resistance of the magnetoresistive effect element layer 1 in the steady state is increased. There is a problem that the resistance value is large and there is an individual difference in the resistance value.

For example, the magnetoresistive effect element layer 1 has a thickness of 35 nm, a short side of 5 μm, and a width (a region of action) sandwiched between the electrode layers 2 and 2 on the long side of 10 μm. Since the specific resistance of permalloy is around 20 μΩcm, while the theoretical electrical resistance value is around 11Ω,
The actual electric resistance value is distributed in the range of 20 to 70Ω, and has a large variation in the range higher than the theoretical value.

Further, in the magnetoresistive effect element layer 1,
As shown in FIG. 12, while it is required to exhibit a uniform resistance change according to the change of the external magnetic field, in the magnetoresistive effect element layer 1 obtained by the conventional procedure, as shown in FIG. As shown in FIG. 13 (b), the resistance change rate jumps sharply, and as shown in FIG. 13 (b), the resistance change rate varies depending on the direction of change of the external magnetic field, so-called hysteresis. As described above, there are some that exhibit unacceptable characteristic defects such as resistance change including a large variation component, which is a factor that hinders improvement of product yield.

Further, the conventional magnetoresistive effect element layer 1 is shown in FIG.
As shown in, the reproduction current I flowing through the electrode layers 2 and 2
_The resistance value tends to increase rapidly as _S increases, and when the reproduction current I _s is increased to obtain a large reproduction output, the overlapping portion between the electrode layers 2 and 2 and the magnetoresistive effect element layer 1 has a magnetoresistance. There is a risk that the effect element layer 1 may be burned due to heat generation and a wire breakage may occur, and there is a limit to improvement of the reproduction output. On the other hand, in order to stabilize the magnetoresistive effect characteristics and achieve a single magnetic domain, it is required to reduce the thickness of the magnetoresistive effect element layer 1 and narrow the width of the action region. In the thin-film magnetic head, there is a concern that the burnout and the wire breakage accident may occur, so that it is the actual situation that the demand cannot be met.

The present invention has been made in view of the above circumstances, and it is possible to stably form a magnetoresistive element layer having desirable characteristics, improve yield, increase reproduction output, and prevent occurrence of burnout disconnection accidents. An object of the present invention is to provide a method of manufacturing a magnetoresistive thin film magnetic head that can contribute.

[0019]

According to a method of manufacturing a thin film magnetic head of the present invention, a magnetoresistive effect having a rectangular shape in a plan view on a lower insulating layer laminated on a substrate via a lower magnetic shield layer. An element layer is formed, and a pair of electrode layers are contacted on both sides in the longitudinal direction of the magnetoresistive effect element layer, and the upper portions thereof are covered with an upper magnetic shield layer laminated with an upper insulating layer interposed therebetween. In a method of manufacturing a magnetoresistive thin film magnetic head for reproducing magnetic recording information by taking out a change in electric resistance value occurring in a resistance effect element layer through the electrode layer, a magnetoresistive effect film is formed on the lower insulating layer. A first step of forming a film, a second step of forming a frame resist corresponding to the planar shape of the magnetoresistive effect element layer on the magnetoresistive effect film, and the lower insulation except the upper part of the frame resist. A third step of forming a metal plating film on the layer, a fourth step of forming a cover resist covering the upper part of the frame resist and the upper part of the metal plating film inside the frame resist, and around the cover resist. A fifth step of removing the exposed metal plating film by wet etching, a sixth step of removing the cover resist and the frame resist, and the magnetic resistance exposed around the metal plating film remaining after the removal of both resists. A seventh step of removing the effect film by dry etching, and an eighth step of removing the remaining metal plating film and leaving the magnetoresistive effect film covered under the metal plating film as the magnetoresistive effect element layer. It is characterized by including.

[0020]

In the present invention, when the unnecessary portion of the magnetoresistive effect film formed on the insulating layer is removed, the upper part of the magnetoresistive effect film left as the magnetoresistive effect element layer after the removal is directly covered with the resist. Instead, a metal plating film is formed on the magnetoresistive effect element layer film, and the upper part of the portion of the metal plating film corresponding to the magnetoresistive effect element layer is covered with a cover resist and the side parts are covered with a frame resist. By covering each of them, by wet etching in this state, first remove unnecessary parts of the metal plating film, then remove the cover resist and frame resist, and use the remaining metal plating film as a mask to remove unnecessary parts of the magnetoresistive film below. Is removed by dry etching, and finally the metal plating film covering the upper part is removed to obtain a magnetoresistive effect element layer.

The present inventor has made a detailed observation of the magnetoresistive effect element layer formed by the conventional method in order to find out the cause of the unstable characteristic occurring in the magnetoresistive effect element layer. Further, it was found that the residue of the resist having a high electric resistance value locally adheres to the surroundings, and the characteristics can be stabilized by carefully wiping off the residue with a cotton swab or the like.

On the other hand, as a result of studying the cause of the residue of the resist adhering to the magnetoresistive effect element layer, the process of FIGS. 8 (c) and 9 (c) in the conventional method, that is, it is covered with the resist. When dry etching is performed to remove the unnecessary magnetoresistive effect film, the resist exposed to plasma is burned into the magnetoresistive effect film by radiant heat. It has been found that this is because they remain attached to the magnetoresistive film.

That is, the cause of the unstable characteristic of the magnetoresistive effect element layer is the residue of the resist used in the process of forming the magnetoresistive effect element layer, and the characteristics are stabilized by surely removing this residue. It can be planned. However, it is not realistic to perform the above-mentioned wiping with a cotton swab at an actual production site, and when the conventionally known method for strengthening the resist stripping solution and the method for removing by oxygen plasma are adopted, the former method is used. Has a problem that the magnetoresistive effect film forming the magnetoresistive effect element layer is damaged, and in the latter case, the surface of the magnetoresistive effect film is oxidized, which becomes a new factor of deterioration of characteristics.

Since the cause of the resist burn-in is the dry etching for removing the unnecessary portion of the magnetoresistive effect film, the magnetoresistive effect film may be removed by wet etching, but it is left after the removal. The magnetoresistive effect element layer is extremely fine, and there is a problem of undercut on the side surface.In order to accurately form the magnetoresistive effect element layer by wet etching, strict control of etching conditions such as temperature and time is required. And The present invention is based on the above findings.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing the embodiments. A method of manufacturing a thin film magnetic head according to the present invention (hereinafter, referred to as the present invention method) includes a magnetoresistive effect element layer 1 which is a main part of a magnetoresistive effect thin film magnetic head configured as shown in FIGS. 6 and 7. Characterized by the forming procedure. 1 to 4 are explanatory views showing a procedure of forming the magnetoresistive effect element layer 1 by the method of the present invention, and FIGS.
A front cross-sectional view from the side facing the recording surface A (see FIG. 7),
3 and 4 are plan views from above of FIGS. 1 and 2, respectively.

First, as in the case of forming the conventional magnetoresistive effect element layer 1, as shown in FIGS. 1A and 3A, the entire surface of the lower insulating layer 4 serving as a base is uniformly formed. A magnetoresistive effect film 10 having a thickness of 20 to 50 nm is formed by a sputtering method in a magnetic field or a vacuum evaporation method. This magnetoresistive film 10 is a single-layer film made of a permalloy (NiFe) -based soft magnetic alloy, a permalloy film, or a cobalt film, like the magnetoresistive film 20 in the conventional procedure shown in FIGS. 8 and 9. The bias film made of a soft magnetic alloy and the magnetic domain control film made of an antiferromagnetic material may be formed in any of three layers, and it is possible to perform the film formation in a magnetic field. This is because the magnetization directions of the magnetoresistive film 10 are aligned by the action of the magnetic field to induce uniaxial magnetic anisotropy.

Then, using a spin coater, a positive photoresist is uniformly applied to the surface of the magnetoresistive film 10 and baked (prebaked), and a photomask having a predetermined exposure pattern is aligned, After exposure through a photomask and development, a known photolithography method is performed in which baking (post-baking) is performed to increase the adhesion strength. However, the exposure pattern of the photomask used in the method of the present invention is different from the case of the conventional forming procedure, and has a frame shape having an inner portion along the outer periphery of the magnetoresistive effect element layer 1 to be obtained. As a result of performing the exposure using the photomask, the lower insulating layer 4 after the photolithography method is performed is exposed as shown in FIG.
As shown in (b) and FIG. 3 (b), a frame resist 11 of a predetermined width that borders the outside of the magnetoresistive effect element layer 1 to be obtained.
Remains.

Next, as shown in FIGS. 1 (c) and 3 (c), a metal film having a thickness of about 100 nm is formed on the surface of the magnetoresistive effect film 10 exposed inside and outside the frame resist 11. To film. Such selective film formation can be achieved by electroplating because the frame resist 11 does not have conductivity. The material of the metal plating film 12 may be selected under the condition that it can be formed by a plating method and can be removed by wet etching described below without invading the magnetoresistive effect film 10. Cu, Cr, Al or Au or the like may be used.

Next, the metal plating film 12 and the metal plating film
A positive photoresist is evenly applied to the surface of the frame resist 11 exposed on the surface 12, and a photolithography method is carried out as in the case of forming the frame resist 11.
The photomask used at this time has a rectangular exposure pattern along the outer edge of the frame resist 11, and by performing the photolithography method with the exposure by this photomask, the photomask shown in FIGS. 1D and 3D is obtained. As shown in
The upper part of the frame resist 11 and the frame resist 11
A cover resist 13 is formed to cover the top of the inner metal plating film 12.

In the above state, wet etching is then carried out to remove the metal plating film 12 exposed around the cover resist 13, and then the frame resist 11 and the cover resist 13 are removed using a resist stripping solution such as acetone. To remove. The etching solution used for performing the wet etching needs to be selected under the condition that the metal plating film 12 can be removed without invading the magnetoresistive film 10, and as described above, as the material of the metal plating film 12,
When Cu, Cr, Al, or Au is used, as the etching solution, for example, an ammonium persulfate aqueous solution such as an ammonium peroxodisulfate aqueous solution, an ammonia aqueous solution containing sodium sulfite, or an alkaline aqueous solution containing potassium ferricyanide can be used.

Frame resist 11 and cover resist 13
The state after the removal is shown in FIGS. 2 (a) and 4 (a). As a result of performing wet etching as described above,
The magnetoresistive effect film 10 remains on the entire surface of the insulating layer 4, and the metal plating film 12 covered with the cover resist 13 remains on the upper part of the magnetoresistive effect 10. In addition, since the wet etching is performed in a state where the side surface of the metal plating film 12 under the cover resist 13 is covered with the frame resist 11, there is no possibility of undercutting on the side surface. As shown in FIG. 4A, the metal plating film 12 remaining on the magnetoresistive effect film 10 accurately corresponds to the inner shape of the frame resist 11, that is, the planar shape of the magnetoresistive effect element layer 1 to be obtained. . Furthermore,
Since the removal of the metal plating film 12 is performed by wet etching, there is no fear that the frame resist 11 and the cover resist 13 will be deteriorated during this period, and both the resists 11 and 13 are subjected to metal plating in the subsequent removal step by the resist stripping solution. The film 12 and the magnetoresistive film 10 are almost completely removed without leaving a residue on the surfaces.

Then, using the remaining metal plating film 12 as a mask, the magnetoresistive effect film 10 exposed around the metal plating film 12 is removed by dry etching. This removal may be performed, for example, by ion milling performed in a direction perpendicular to the magnetoresistive film 10 under the conditions of an acceleration voltage of 500 V and an acceleration current of 200 mA. The state after this step is as shown in FIG. 2 (b) and FIG. 4 (b),
The magnetoresistive film 10 under the metal plating film 12 remains on the insulating layer 4 serving as a base, and the planar shape of the magnetoresistive film 10 is removed by dry etching on the outside thereof. Therefore, the metal plating film used as a mask
This corresponds exactly to the twelve planar shapes, that is, the planar shape of the magnetoresistive effect element layer 1 to be obtained.

Finally, the remaining metal plating film 12 is removed by wet etching using the above-mentioned etching solution. As a result, only the magnetoresistive film 10 covered with the metal plating film 12 remains on the lower insulating layer 4 as shown in FIGS.
10 forms the magnetoresistive effect element layer 1 having a desired planar shape. 10 and 11 are formed on the magnetoresistive effect element layer 1.
The electrode layers 2 and 2 are formed by the conventional procedure shown in FIG. 1, and the upper insulating layer 3 and the upper magnetic shield layer 5 are further formed.
Finally, the whole is covered with a protective film 9 to form a thin film magnetic head as shown in FIGS.

In the thin film magnetic head obtained by the method of the present invention as described above, the electric resistance value of the magnetoresistive effect element layer 1 was examined. As a result, the thickness was 35 nm, the short side was 5 μm and the long side was the same as in the conventional case. In the magnetoresistive effect element layer 1 in which the width (working area) sandwiched between the electrode layers 2 and 2 is 10 μm, it is distributed in a narrow range of 10 to 12 Ω, and these resistance values are theoretically Is approximately equal to 11Ω which is the electric resistance value of.

Further, in the magnetoresistive effect element layer 1, as a result of examining the rate of change in electric resistance according to the change in the external magnetic field,
The change characteristics shown in FIG. 12 are obtained, the resistance change rate jumps shown in FIG. 13 (a), the hysteresis shown in FIG.
It was found that the occurrence of characteristic defects such as resistance change including the fluctuation component shown in 13 (c) can be eliminated. Further, the characteristics as described above were stably obtained even after repeating the increase and decrease of the external magnetic field many times.

Further, in the magnetoresistive effect element layer 1 obtained by the method of the present invention, as shown in FIG.
The change in the resistance value is small when the reproducing current I _S flowing through 2 is increased, which is clearly superior in comparison with the similar result (see FIG. 14) in the conventional magnetoresistive effect element layer 1. Sex is recognized. From this fact, in the thin film magnetic head obtained by the method of the present invention, the reproducing current I flowing through the electrode layers 2 and 2 without causing burnout or disconnection of the overlapping portion between the electrode layers 2 and 2 and the magnetoresistive effect element layer 1. _s can be increased, and the reproduction output can be greatly improved.

In the thin film magnetic head obtained by the method of the present invention, the number of occurrences of burnout and wire breakage was actually examined.
In the conventional thin film magnetic head, 40 pieces out of 100 pieces were burnt out and broken, while the number was 2 to 3 pieces out of 00 pieces.
It has become clear that the yield can be significantly improved.

[0038]

As described in detail above, in the method of the present invention, when the unnecessary portion of the magnetoresistive effect film formed on the insulating layer is removed to form the magnetoresistive effect element layer, the magnetoresistive effect layer is removed after the removal. Instead of directly covering the upper part of the magnetoresistive effect film to be left as an element layer with a resist, the metal plating film formed on the upper part of the magnetoresistive effect element layer film is covered with a resist to remove unnecessary portions of the metal plating film. A procedure is adopted in which the unnecessary portion of the lower magnetoresistive film is removed by dry etching using the metal plating film remaining after the removal of the resist as a mask, and finally the metal plating film covering the upper part is removed. From
There is no possibility that the residue of the resist adheres to the obtained magnetoresistive effect element layer, and the occurrence of characteristic defects due to this residue can be effectively prevented.

Further, since the wet etching of the metal plating film is performed with the upper part of the necessary part covered with the cover resist and the side part with the frame resist, strict control of the etching temperature and time is required. A desired residual shape can be obtained without any damage, and a fine magnetoresistive effect element layer can be stably formed by dry etching using this remaining portion as a mask, improving yield, increasing read output and causing burnout disconnection accidents. The present invention has excellent effects such as contributing to prevention.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a procedure of forming a magnetoresistive effect element layer by the method of the present invention.

FIG. 2 is an explanatory diagram of a procedure for forming a magnetoresistive effect element layer by the method of the present invention.

FIG. 3 is an explanatory view of a procedure for forming a magnetoresistive effect element layer by the method of the present invention.

FIG. 4 is an explanatory view of a procedure for forming a magnetoresistive effect element layer by the method of the present invention.

FIG. 5 is a diagram showing a change in resistance value with respect to an increase in reproduction current in the magnetoresistive effect element layer obtained by the method of the present invention.

FIG. 6 is a front view of a magnetoresistive thin-film magnetic head.

FIG. 7 is a longitudinal sectional view showing a usage state of a magnetoresistive thin film magnetic head.

FIG. 8 is an explanatory diagram of a conventional procedure for forming a magnetoresistive effect element layer.

FIG. 9 is an explanatory diagram of a conventional procedure for forming a magnetoresistive effect element layer.

FIG. 10 is an explanatory diagram of a procedure for forming an electrode layer.

FIG. 11 is an explanatory diagram of a procedure for forming an electrode layer.

FIG. 12 is a diagram showing desirable resistance change characteristics of a magnetoresistive effect element layer.

FIG. 13 is an exemplary diagram of a resistance change characteristic defect that occurs in a conventional magnetoresistive effect element layer.

FIG. 14 is a diagram showing a change in resistance value with an increase in reproduction current in a conventional magnetoresistive effect element layer.

[Explanation of symbols]

 1 Magnetoresistive Element Layer 2 Electrode Layer 4 Lower Insulating Layer 10 Magnetoresistive Effect Film 11 Frame Resist 12 Metal Plating Film 13 Cover Resist

Claims (1)

[Claims] 1. A magnetoresistive effect element layer having a rectangular shape in a plan view is formed on a lower insulating layer laminated on a substrate via a lower magnetic shield layer, and both sides of the magnetoresistive effect element layer in the longitudinal direction are formed. And a pair of electrode layers are brought into contact with each other, and the upper portions thereof are covered with an upper magnetic shield layer laminated with an upper insulating layer interposed therebetween. In a method of manufacturing a magnetoresistive effect thin film magnetic head for reproducing magnetic recording information by taking out through a via, a first step of forming a magnetoresistive effect film on the lower insulating layer, and a step of forming a magnetoresistive effect film on the magnetoresistive effect film. A second step of forming a frame resist corresponding to the planar shape of the magnetoresistive element layer, a third step of forming a metal plating film on the lower insulating layer except the upper portion of the frame resist, and the frame resist. A fourth step of forming a cover resist covering the upper part of the resist and the upper part of the metal plating film inside the frame resist, and a fifth step of removing the metal plating film exposed around the cover resist by wet etching, Sixth step of removing the cover resist and the frame resist, a seventh step of removing the magnetoresistive film exposed around the metal plating film remaining after removing both resists by dry etching, and the remaining metal plating An eighth step of removing the film and leaving the magnetoresistive effect film covered under the metal plating film as the magnetoresistive effect element layer.