JP2003085710A - Thin-film magnetic head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin-film magnetic head capable of suppressing magnetic interference between a recording head and a reproducing head even in a high recording density and its manufacturing method, as for a piggy-back type thin- film magnetic head constituted of a recording head and a reproducing head formed via an insulating layer on the recording head. SOLUTION: A lower core layer 28 and an upper shield layer 26 are partially conducted and connected by a conductive layer 43. Thus, the lower core layer 28 and the upper shield layer 26 are set to equal potentials. Even when a solvent used during manufacturing or moisture in air permeates a protective layer 44 to reach the lower core layer 28 and the upper shield layer 26, the corrosion of the lower core layer 28 and the upper shield layer 26 is properly suppressed by a battery effect.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head,
A piggyback including a reproducing head formed on the recording head via an insulating layer.
Type thin-film magnetic head, particularly capable of suppressing magnetic interference between the recording head and the reproducing head even at high recording density and improving corrosion resistance, and manufacturing thereof Regarding the method.

[0002]

17 is a partial vertical sectional view of the structure of a conventional thin film magnetic head. Here, the vertical section refers to a section obtained by cutting the thin-film magnetic head in the height direction (Y direction in the drawing) and parallel to the film thickness direction. The meaning of the longitudinal section is the same below.

Reference numeral 1 shown in FIG. 17 is a slider made of alumina-titanium carbide (Al ₂ O ₃ -TiC), and a thin film magnetic head 3 is formed on the slider 1 with an Al ₂ O ₃ film 2 interposed therebetween. To be done.

A thin-film magnetic head 3 shown in FIG. 17 has a reproducing MR head h1 and a recording inductive head h2.
The MR head h2 has a lower shield layer 4 made of a magnetic material, for example, a magnetoresistive effect element 5 utilizing the giant magnetoresistive effect (GMR effect), the lower shield layer 4 and the magnetic layer. It is composed of a gap layer 6 made of an insulating material formed above and below the resistance effect element 5, and an upper shield layer 7 made of a magnetic material formed on the gap layer 6.

In a thin film magnetic head 3 of the type shown in FIG. 17, the upper shield layer 7 is an inductive head h2.
Also functions as the lower core layer of. That is, the upper shield layer 7 has both a function as a shield for the MR head h1 and a function as a core for the inductive head h2.

The inductive head h2 includes a lower core layer 7, a magnetic gap layer 8 made of Al ₂ O _3, etc.
It comprises a coil layer 9, an insulating layer 10 formed above and below the coil layer 9, and an upper core layer 11.

As shown in FIG. 17, the tip end portion 11a of the upper core layer 11 is a front end face of the thin film magnetic head 3 (recording medium D).
The surface facing the lower core layer 7 with the magnetic gap layer 8 therebetween, and the base end portion 1 of the upper core layer 11
1b is magnetically connected to the surface of the lower core layer 7 on the rear side in the height direction (Y direction in the drawing).

The upper core layer 11 is covered with a protective layer 12 made of Al ₂ O ₃ or the like.

As shown in FIG. 17, the front end surface (the surface facing the recording medium D) of the thin film magnetic head 3 is protected by DLC (diamond-like carbon) having a predetermined thickness. The layer 13 is formed.

However, the structure of the thin film magnetic head shown in FIG. 17 has the following problems. That is, in the thin film magnetic head shown in FIG. 17, since the upper shield layer 7 that functions as a shield of the MR head h1 also functions as the lower core layer of the inductive head h2, the magnetic action of the lower core layer 7 during recording, for example, Even when the mode is switched to the reproducing mode, it remains slightly, resulting in reducing the function of the lower core layer 7 as the upper shield during the reproducing mode. Particularly, such a problem of magnetic interference at the time of switching between the recording mode and the reproducing mode. It became more and more prominent with the increase in recording density.

Therefore, the structure of the thin film magnetic head shown in FIG. 17 has been improved as shown in FIG. In FIG. 18, the layers having the same reference numerals as those in FIG. 17 indicate the same layers as those in FIG. FIG.
In the above, the upper shield layer 14 and the lower core layer 15 are separately formed, and the insulating layer 16 such as Al ₂ O ₃ is interposed between the upper shield layer 14 and the lower core layer 15.

As shown in FIG. 18, a thin film magnetic head in which the MR head h1 and the inductive head h2 are formed by being completely separated from each other without using the same layer, is a piggyback.
y back) type thin film magnetic head.

With the piggyback type thin film magnetic head, magnetic interference between the MR head h1 and the inductive head h2 can be suppressed even when the recording density is increased, and both the recording and reproducing characteristics are appropriately improved. It was thought to be possible.

[0014]

However, when the lower core layer 15 and the upper shield layer 14 are separated as in the thin film magnetic head having the structure shown in FIG. 18, the lower core layer 15 is separated.
It was pointed out that the upper shield layer 14 is easily corroded. This problem becomes more remarkable as the recording density becomes higher.

In order to realize the high recording density more effectively, it is necessary to reduce the spacing loss. In order to reduce the spacing loss, the flying distance H1 from the front end surface (the surface facing the recording medium D) of the thin film magnetic head 3 shown in FIG. 18 to the surface of the recording medium D may be shortened.

In order to shorten the flying distance H1, the flying height when the thin film magnetic head 3 flies above the recording medium D is reduced, and the protective layer formed on the front end surface of the thin film magnetic head 3 is reduced. It is necessary to reduce the film thickness T1 of 13.

However, the thickness T1 of the protective layer 13
When the thickness is reduced, defects such as pinholes are formed in the protective layer 13, and, for example, a solvent used in the process of manufacturing the magnetic head 3 or moisture in the air permeates into the protective layer 13 to lower the core. It is easy to reach the layer 15 and the upper shield layer 14. At this time, since a potential difference is generated between the lower core layer 15 and the upper shield layer 14, both the lower core layer 15 and the upper shield layer 14 are caused by the battery effect due to the potential difference between the lower core layer 15 and the upper shield layer 14. Or, there was a problem that one of them was particularly corroded.

In the case of the piggyback type shown in FIG. 18, since the lower core layer 15 and the upper shield layer 14 are formed separately, the lower core layer 15 and the upper shield layer 14 are made of different magnetic materials. It is also possible to form the lower core layer 15 and the upper shield layer 14 in such a case.
Since the potential difference between the layers further increases, the layer having a particularly high ionization tendency is corroded violently due to the battery effect, and the recording characteristics and the reproducing characteristics are likely to be significantly deteriorated.

Further, it is important to solve the above-mentioned problem of corrosion in order to increase the recording density, but at the same time as improving the corrosion resistance, the advantage of using the piggyback type,
That is, it is necessary to prevent the effect of appropriately reducing the magnetic interference between the MR head h1 and the inductive head h2 from decreasing.

Therefore, the present invention is to solve the above-mentioned conventional problems and, in particular, to an inductive head and an MR.
While maintaining the effect of reducing the magnetic interference between the heads, the lower core layer and the upper shield layer are electrically connected by a conductive layer so that the lower core layer and the upper shield layer have the same potential, An object of the present invention is to provide a thin film magnetic head capable of appropriately improving the corrosion resistance of the core layer and the upper shield layer, and a method of manufacturing the thin film magnetic head.

[0021]

According to the present invention, there is provided a reproducing head having a lower shield layer, a magnetoresistive element, and an upper shield layer, and a lower core facing the upper shield layer with an insulating layer interposed therebetween. A thin film magnetic head comprising a layer, a magnetic gap layer, an upper core layer, and a coil layer formed between the lower core layer and the upper core layer. It is characterized in that a part thereof is electrically connected by a conductive layer.

When the upper shield layer and the lower core layer are partially electrically connected by a conductive layer as in the present invention, the upper shield layer and the lower core layer have the same potential, so that the front end face of the thin film magnetic head (recording) Even if the protective layer formed on the surface facing the medium) is thinned to reduce spacing loss,
The battery effect caused by permeation of solvent or moisture in the air is reduced as compared with the conventional case, and the corrosion resistance between the upper shield layer and the lower core layer can be improved.

Even when the upper shield layer and the lower core layer are electrically connected by a conductive layer as in the present invention, the conductive layer is provided only in a part between the upper shield layer and the lower core layer. Therefore, compared with the conventional case (the conventional example of FIG. 17) in which the lower core layer and the upper shield layer serve as magnetic interference between the lower core layer and the upper shield layer during recording and reproducing, The piggyback type can maintain its superiority.

In the present invention, the conductive layer may be formed of a magnetic material. In such a case, it is preferable that the conductive layer be formed of the same material as the lower core layer. This can facilitate the manufacturing process of the conductive layer.

Further, in the present invention, the conductive layer is preferably formed of a non-magnetic conductive material, and in such a case, the non-magnetic conductive material is NiP, Cu, Al, Cr, Au.
It is preferable to select one kind or two kinds or more.
When the conductive layer is formed of a non-magnetic conductive material, magnetic interference between the lower core layer and the upper shield layer can be more appropriately and easily reduced, and the superiority as a piggyback type can be appropriately maintained. it can.

Further, in the present invention, the base end portion of the upper core layer is magnetically connected to the lower core layer rearward in the height direction, and the front end face of the conductive layer is more than the front end face of the base end portion. Is also preferably formed rearward in the height direction.

Alternatively, in the present invention, the upper core layer and the lower core layer are magnetically connected to each other in the height direction via a back gap layer, and the front end face of the conductive layer is the front end face of the back gap layer. It is preferable to be formed rearward in the height direction.

As described above, the front end face of the conductive layer is
If it is formed on the front end face of the base end portion of the upper core layer or on the height side of the front end face of the back gap layer, even if the conductive layer is a magnetic material, recording is performed between the lower core layer and the upper core layer. A magnetic field has little or no effect on the upper shield layer through the conductive layer, and thus appropriately suppresses magnetic interference between the lower core layer and the upper shield layer during recording and reproduction. it can.

Further, in the present invention, it is preferable that the cross-sectional area of the conductive layer in the direction parallel to the film surface is 1 μm ² or more and 500 μm ² or less. This makes it possible to more appropriately suppress magnetic interference between the lower core layer and the upper shield layer during recording and reproduction.

Further, in the present invention, it is preferable that the lower core layer and the upper shield layer are made of different magnetic materials. The magnetic characteristics required for the lower core layer are particularly high saturation magnetic flux density Bs. On the other hand, the magnetic properties required for the upper shield layer are particularly high magnetic permeability and low magnetostriction constant, and the saturation magnetic flux density Bs need not be as high as that of the lower core layer.
Since the magnetic properties required for the lower core layer and the upper shield layer are different from each other, the lower core layer and the upper shield layer are made of different magnetic materials, and the core function of the lower core layer and the upper shield layer are formed. It is preferable to improve the shielding function of.

In the present invention, a protective layer is formed on the front end face of the thin film magnetic head, and the thickness of the protective layer is 0.
It is preferably 5 nm or more and 5 nm or less. As a result, the spacing loss can be appropriately reduced, and a thin film magnetic head that can cope with high recording density can be manufactured. In the present invention, the protective layer is formed of DLC (diamond-like carbon) or ta-C (Tetrahedral Amorphous Carbon).
Of these, it is preferable to be formed of one kind or two or more kinds.

The method of manufacturing a thin film magnetic head according to the present invention is characterized by including the following steps. (A) a step of forming a reproducing head having a lower shield layer, a magnetoresistive effect element and an upper shield layer, and (b) forming a conductive layer on a part of the upper shield layer and surrounding the conductive layer. A step of forming an insulating layer,
(C) forming a lower core layer from the insulating layer to the conductive layer, and (d) forming a coil layer and an upper core layer on the lower core layer, and forming the lower core layer, the coil layer,
And a step of forming a recording head having an upper core layer.

According to the method of manufacturing a thin film magnetic head of the present invention described above, a conductive layer can be appropriately and easily formed in a part between the lower core layer and the upper shield layer to electrically connect the lower core layer and the upper shield layer. By connecting the lower core layer and the upper shield layer to the same potential, it is possible to manufacture a thin film magnetic head having excellent corrosion resistance.

Further, in the present invention, it is preferable to have the following steps in place of the steps (b) and (c). (E) a step of forming an insulating layer on the upper shield layer, forming a hole in the insulating layer that penetrates to the upper shield layer, and forming a plating underlayer from the inside of the hole to the insulating layer. (F) A step of forming a lower core layer on the plating base layer by plating, and forming a conductive layer integrated with the lower core layer in the hole.

Accordingly, the lower core layer and the conductive layer can be simultaneously formed in the same process. Therefore, it is preferable because the production of the conductive layer can be facilitated.

Further, in the present invention, in the step (d), the front end face of the base end portion of the upper core layer magnetically connected to the lower core layer, or the lower core layer in the step (d) is used. It is preferable to form the front end surface of the back gap layer formed between the base end portions of the upper core layer and the upper core layer so as to be located closer to the recording medium than the front end surface of the conductive layer. As a result, it is possible to more appropriately manufacture a thin film magnetic head capable of suppressing magnetic interference between the lower core layer and the upper shield layer during recording and reproduction.

In the present invention, it is preferable that the lower core layer is made of a magnetic material different from that of the upper shield layer in the steps (c) and (f).

Since the thin film magnetic head of the present invention is a piggyback type, the lower core layer and the upper shield layer can be formed of different magnetic materials. At this time, it is preferable to select a material having magnetic properties required to improve the core function of the lower core layer and magnetic properties required to improve the shield function of the upper shield layer.

Further, in the present invention, after the step (d), a protective layer is formed on the surface facing the recording medium, and the thickness of the protective layer is 0.5 nm or more and 5 nm or less. It is preferable. As a result, it is possible to reduce the spacing loss and manufacture a thin film magnetic head that can appropriately cope with higher recording density.

Further, in the present invention, the protective layer is formed of DLC.
(Diamond-like carbon), ta-C (Tetrahed
Ral Amorphous Carbon) is preferably formed of one kind or two or more kinds.

[0041]

1 is a partial vertical sectional view of a thin film magnetic head according to a first embodiment of the present invention. In the following, the X direction shown in FIG. 1 is called the track width direction, and the Y direction shown in the drawing is called the height direction. Recording medium D in the Z direction in the figure
Is the moving direction of.

The thin film magnetic head shown in FIG.
The R head h1 and the recording inductive head h2 are thin film magnetic heads of a type called a piggy back type in which the R head h1 and the recording inductive head h2 are separately formed without having a shared layer.

Reference numeral 20 shown in FIG. 1 is a slider formed of alumina-titanium carbide (Al ₂ O ₃ -TiC) or the like. The thin film magnetic head 21 according to the present invention comprises an insulating layer 2 such as Al ₂ O ₃ or SiO ₂ on the slider 20.
2 is formed.

As shown in FIG. 1, permalloy (NiFe alloy) or sendust (Fe-A) is formed on the insulating layer 22.
A lower shield layer 23 made of a magnetic material such as an (1-Si alloy) is formed.

A magnetoresistive effect element 25 is formed on the lower shield layer 23 via a gap layer 24. The front end surface of the magnetoresistive effect element 25 is formed on the same surface as the front end surface of the thin film magnetic head 21 (the surface facing the recording medium D), as shown in FIG. The magnetoresistive effect element 25 is, for example, a giant magnetoresistive effect element represented by a spin valve thin film element utilizing a giant magnetoresistive effect (GMR effect), or a tunnel type magnetoresistive effect type utilizing a tunnel effect (TMR effect). Element, anisotropic magnetic effect (AMR
Is an anisotropic magnetoresistive effect element utilizing the effect.

As shown in FIG. 1, the gap layer 24 is also formed on the magnetoresistive effect element 25, and the upper and lower sides (Z direction in the drawing) of the magnetoresistive effect element 25 are surrounded by the gap layer 24. ing. Normally, the gap layer 24 formed below the magnetoresistive effect element 25 is called a lower gap layer, and the gap layer 24 formed above the magnetoresistive effect element 25 is called an upper gap layer. The lower gap layer and the upper gap layer are simplified in the drawing and shown as one gap layer 24.

As shown in FIG. 1, an upper shield layer 26 made of a magnetic material such as permalloy is formed on the gap layer 24.

As shown in FIG. 1, the lower shield layer 2
3 and the front end surfaces of the upper shield layer 26 are formed on the same surface as the front end surface of the magnetoresistive effect element 25 and the front end surface of the thin film magnetic head 21 (the surface facing the recording medium D).

The portion from the lower shield layer 23 to the upper shield layer 26 shown in FIG. 1 is the reproducing head, that is, the MR head h1.

As shown in FIG. 1, the upper shield layer 26 is formed.
An insulating layer (separation layer) 27 made of an insulating material such as Al ₂ O ₃ or SiO ₂ is formed on the top.

As shown in FIG. 1, N is formed on the insulating layer 27.
A lower core layer 28 made of a magnetic material such as an iFe alloy (permalloy) is formed.

A Gd determining layer 29 made of, for example, an organic material is formed on the lower core layer 28 at a position apart from the front end face of the thin film magnetic head 21 in the height direction (Y direction in the drawing).
Are formed. A back gap layer 30 made of a magnetic material is formed further behind the Gd determining layer 29 in the height direction (Y direction in the drawing). The back gap layer 30 is magnetically connected to the lower core layer 28.

As shown in FIG. 1, the lower magnetic pole layer 31, the magnetic gap layer 32, and the upper magnetic pole are formed from the bottom to the front end surface (the surface facing the recording medium D) of the thin film magnetic head 21 from the Gd determining layer 29. A pole layer 34 including the layer 33 is formed. The lower magnetic pole layer 31 and the upper magnetic pole layer 33 are N
It is formed of a magnetic material such as an iFe-based alloy, a CoFe-based alloy, a CoFeNi-based alloy. On the other hand, the magnetic gap layer 32 is formed of a non-magnetic conductive material such as NiP that can be plated.

As shown in FIG. 1, between the pole layer 34 and the back gap layer 30 and on the lower core layer 28,
A first coil layer 36 made of a non-magnetic conductive material such as Cu is wound around an insulating underlying layer 35 such as Al ₂ O ₃ .

A space between the conductor portions of the first coil layer 36 is filled with an organic insulating material layer 37 such as a resist, and the first coil layer 36 and the organic insulating material layer 3 are filled with each other.
7 is covered with a layer 38 of an inorganic insulating material such as Al ₂ O ₃ . The surfaces of the inorganic insulating material layer 38, the pole layer 34, and the back gap layer 30 are planarized by using the CMP technique or the like.

As shown in FIG. 1, the inorganic insulating material layer 3 is formed.
The second coil layer 39 is wound on the coil 8. Figure 1
2, the second coil layer 39 is covered with an organic insulating material layer 40 such as a resist, and on the organic insulating material layer 40, an upper core layer 41 formed of a magnetic material such as a NiFe alloy. Are formed by, for example, a frame plating method. As shown in FIG. 1, the tip portion 41 a of the upper core layer 41 is magnetically connected to the upper magnetic pole layer 33. In this embodiment, the tip 41
The front end surface of a is not formed on the same surface as the front end surface of the thin film magnetic head 21 (the surface facing the recording medium D), and is recessed in the height direction (Y direction in the drawing). 41
The front end face of a may be formed on the same plane as the front end face of the thin film magnetic head 21.

The base end portion 41b of the upper core layer 41 is magnetically connected to the back gap layer 30.

Each layer from the lower core layer 28 to the upper core layer 41 shown in FIG. 1 constitutes a recording head, that is, an inductive head h2.

In the inductive head h2, the first
When a recording current flows through the coil layer 36 and the second coil layer 39, a recording magnetic field is generated, and the upper magnetic pole layer 33-the upper core layer 41.
A magnetic path passing through the back gap layer 30, the lower core layer 28, and the lower magnetic pole layer 31 is formed. The magnetic gap layer 32
A signal is recorded on the recording medium D by the leakage magnetic field from between the lower magnetic pole layer 31 and the upper magnetic pole layer 33 sandwiching the magnetic field.

As shown in FIG. 1, the upper core layer 41 is covered with a protective layer 42 such as Al ₂ O ₃ . Further, as shown in FIG. 1, a protective layer 44 is formed on the front end surface (the surface facing the recording medium D) of the thin film magnetic head 21. The protective layer 44 is formed of DLC (diamond-like carbon), ta-C (Tetrahedral Amorphous Ca).
It is preferable that one or more of rbon) are formed.

Characteristic portions of the thin film magnetic head of the present invention will be described below. A part of the upper shield layer 26 and the lower core layer 28 is electrically connected by the conductive layer 43. When the conductive layer 43 electrically connects between the upper shield layer 26 and the lower core layer 28, the upper shield layer 26 and the lower core layer 28 can have the same potential.

Therefore, when the thin film magnetic head is immersed in a solvent during the manufacturing process of the thin film magnetic head 21, the solvent permeates from the protective film 43 formed on the front end surface of the thin film magnetic head 21, and Moisture in the air permeates from the protective film 43 formed on the front end surface of the thin-film magnetic head 21 when the magnetic head is driven, and the solvent and water penetrate the upper shield layer 26 and the lower core layer 28. Even if it reaches, an electric effect is hard to occur or does not occur between the upper shield layer 26 and the lower core layer 28, and corrosion of the upper shield layer 26 and the lower core layer 28 is appropriately suppressed as compared with the conventional case. be able to.

Further, as in the present invention, the upper shield layer 2
6 and the lower core layer 28 are electrically connected by the conductive layer 43, the conductive layer 43 is provided only in a part between the upper shield layer 26 and the lower core layer 28. Magnetic interference between the lower shield layer 28 and the upper shield layer 26 can be made smaller than in the conventional case (the conventional example of FIG. 17) in which the lower core layer 28 and the upper shield layer 26 are formed of the same layer, and the piggyback is achieved. It is possible to properly maintain the superiority as a mold. Further, when the conductive layer 43 is formed of a non-magnetic conductive material, magnetic interference between the lower core layer 28 and the upper shield layer 26 may be prevented and the conventional conductive layer 43 may not be formed (see the conventional structure of FIG. 18). It can be relaxed in the same way as the example), and it becomes possible to more appropriately maintain the superiority of the piggyback type.

In the present invention, the thin film magnetic head 21 is also used.
The thickness of the protective layer 44 formed on the front end surface of the
It is preferably 5 nm or less. As a result, the flying distance H2 between the front end surface of the thin film magnetic head 21 and the recording medium D can be shortened, and the spacing loss can be reduced. Further, in the present invention, the protective layer 44 is formed thin as described above, so that the protective layer 4 is formed.
4 has a defect such as a pinhole, and the thin film magnetic head 2
Even if the solvent or water in the air used in the manufacturing process of No. 1 easily penetrates into the lower core layer 28 and the upper shield layer 26, in the present invention, as described above, the lower core layer 28 and the upper shield layer 26 are By setting the same potential as 26, a battery effect is less likely to occur between the lower core layer 28 and the upper shield layer 26, and the lower core layer 28 and the upper shield layer 26 are less likely to be corroded as compared with the conventional case. It is possible to manufacture a thin film magnetic head having excellent reproduction characteristics and recording characteristics.

Next, the material of the conductive layer 43 will be described below. The conductive layer 43 may be formed of a magnetic material. In the present invention, even if the conductive layer 43 is formed of a magnetic material, the conductive layer 43 is formed only in a part between the lower core layer 28 and the upper shield layer 26. Compared to the case where the core layer 28 and the upper shield layer 26 are formed of the same layer, magnetic interference between the lower core layer 28 and the upper shield layer 26 during recording and reproducing can be appropriately suppressed. It is possible to maintain the superiority of the piggyback type.

Further, particularly when the conductive layer 43 is formed of a magnetic material, the conductive layer 43 can be formed of the same material as the lower core layer 28, and the formation of the conductive layer 43 can be facilitated.

FIG. 2 is a partially enlarged vertical cross-sectional view showing a state in which the lower core layer 28 and the conductive layer 43 are formed of the same material and integrated.

As shown in FIG. 2, the upper shield layer 26 is formed.
An insulating layer 27 is formed on the upper side, and a hole 27a is formed in the insulating layer 43 so as to penetrate to the upper surface of the upper shield layer 26. Then, from the top of the insulating layer 27 to the hole 2
A plating base layer 45 is formed on the upper shield layer 26 exposed from 7a. The plating base layer 45 is made of a NiFe alloy or the like, and is formed by sputtering, for example. Then, the lower core layer 28 is formed on the plating base layer 45 by electroplating. At this time, a plating layer is also formed in the hole 27a formed in the insulating layer 27, and this plating layer functions as a conductive layer 43 for electrically connecting the lower core layer 28 and the upper shield layer 26.

Alternatively, in the present invention, the conductive layer 43 may be formed separately from the lower core layer 28. This state is shown in the partially enlarged sectional view of FIG.

A conductive layer 43 is formed on the upper shield layer 26 shown in FIG. The conductive layer 43 may be made of a magnetic material or a non-magnetic conductive material.

As shown in FIG. 3, the periphery of the conductive layer 43 is covered with the insulating layer 27. As shown in FIG. 3, it is preferable that the upper surface of the conductive layer 43 and the upper surface of the insulating layer 27 are formed in the same plane, but it is not necessary. A plating underlayer 46 is formed from the upper surface of the conductive layer 43 to the upper surface of the insulating layer 27, and the lower core layer 28 is plated on the plating underlayer 46.

When the conductive layer 43 is made of a non-magnetic conductive material, as described above, magnetic interference between the lower core layer 28 and the upper shield layer 26 at the time of recording and reproducing is prevented by the conventional piggyback. Type thin-film magnetic head, and can effectively maintain its superiority as a piggyback type.

In the present invention, the non-magnetic conductive material is
It is preferable to select one kind or two or more kinds from NiP, Cu, Al, Cr and Au.

Next, the formation position of the conductive layer 29 will be described below. FIG. 4 is a partial plan view of the thin-film magnetic head 21 as seen from above. In order to make it easier to see the formation position of the conductive layer 29, the upper shield layer 26, the conductive layer 43, and the lower core constituting the thin-film magnetic head 29 are shown. Only layer 28 and back gap layer 30 are mainly shown.

As shown in FIG. 4, the front end face 43a of the conductive layer 29 is the front end face 30a of the back gap layer 30.
It is preferable to be formed so as to recede rearward in the height direction (Y direction in the drawing).

In the inductive head h2 of the thin film magnetic head 21 of the present invention, at the time of recording, the upper magnetic pole layer 33-the upper core layer 41-the back gap layer 30-the lower core layer 28.
A magnetic path through the bottom pole layer 31 is formed.

At this time, if the conductive layer 43 is a magnetic material, the front end face 43a of the conductive layer 43 is closer to the recording medium D side than the front end face 30a of the back gap layer 30 (Y in the drawing).
In the direction opposite to the direction), part of the recording magnetic field is easily guided from the back gap layer 30 to the upper shield layer 26 via the lower core layer 28 and the conductive layer 43.

Therefore, in order to prevent a part of the recording magnetic field from being guided to the upper shield layer 26 via the conductive layer 43, the front end face 43a of the conductive layer 43 is formed on the back gap layer 30. It is preferable that the front end face 30a is formed so as to recede rearward in the height direction (Y direction in the drawing). This makes it difficult for the recording magnetic field to be guided to the upper shield layer 26 via the conductive layer 43, and at the time of recording and reproducing, as in the conventional piggyback type thin film magnetic head (see FIG. 18), the lower core layer 28 is formed. And the upper shield layer 26
It is possible to manufacture a thin film magnetic head capable of reducing magnetic interference between the thin film magnetic head and the magnetic head.

Further preferably, the front end face 43a of the conductive layer 43 is the rear end face 30 of the back gap layer 30.
It is possible to more effectively suppress the recording magnetic field from being guided to the upper shield layer 26 via the conductive layer 43 when it is formed behind b in the height direction (Y direction in the drawing), and at the time of recording and reproduction. At times, it is possible to manufacture a thin film magnetic head capable of further reducing magnetic interference between the lower core layer 28 and the upper shield layer 26.

The conductive layer 43 is preferably formed in the middle of the lower core layer 28 and the upper shield layer 26 in the track width direction (X direction in the drawing). The influence of an external magnetic field on the lower core layer 28 and the upper shield layer 26 can be weakened, and a thin film magnetic head having excellent reproduction characteristics and recording characteristics can be manufactured.

When the conductive layer 43 is made of a non-magnetic conductive material, the recording magnetic field is not guided from the lower core layer 28 to the upper shield layer 26 through the conductive layer 43, so Even if the front end face 43a of the layer 43 is located closer to the recording medium D side than the front end face 30a of the back gap layer 30, compared to the case where the conductive layer 43 is made of a magnetic material, the lower core layer 28 and the upper part Shield layer 26
It is considered that problems such as increased magnetic interference between the two will not occur.

Further, in the present invention, as shown in FIG. 5 (which is a second embodiment of the thin film magnetic head of the present invention and is a partial longitudinal sectional view of the thin film magnetic head), an upper core layer 41 and a back gap layer 30 are provided. May be integrated, and the base end portion 41b of the upper core layer 41 may be magnetically connected to the upper surface of the lower core layer 28.

Even in such a case, it is preferable that the front end face 43a of the conductive layer 43 is formed so as to recede rearward in the height direction (Y direction in the drawing) from the front end face 41c of the base end portion 41b, and more preferably. Is formed rearward in the height direction with respect to the rear end surface 41d of the base end portion 41b. Accordingly, even when the conductive layer 43 is made of a magnetic material, it is possible to appropriately suppress the recording magnetic field from being guided from the lower core layer 28 to the upper shield layer 26 via the conductive layer 43, and to achieve a high recording density in the future. It is possible to form the thin-film magnetic head 21 excellent in recording characteristics and reproducing characteristics even in the realization. Note that FIG. 5 shows the base end portion 41 of the upper core layer 41.
The structure b is different from that of FIG. 1, and the other structures are the same as those of FIG.

The cross-sectional area in the direction parallel to the film surface of the conductive layer 43 (the surface formed by the X direction and the Y direction in the drawing) is preferably 1 μm ² or more and 500 μm ² or less. If the cross-sectional area in the direction parallel to the film surface of the conductive layer 43 is smaller than 1 μm ² , it is difficult to form the conductive layer 43 in a predetermined shape, and the lower core layer 2
8 and the upper shield layer 26 are not preferable because it is difficult to make a proper conductive connection between them.

On the other hand, when the cross-sectional area of the conductive layer 43 in the direction parallel to the film surface is larger than 500 μm ² , the lower core is formed during recording and reproduction, especially when the conductive layer 43 is made of a magnetic material. Layer 28 and top shield layer 26
Magnetic interference easily occurs between them, and the superiority as a piggyback type cannot be maintained, which is not preferable.

In the present invention, the cross-sectional area of the conductive layer 43 in the direction parallel to the film surface is 0.1% or more and 60% or less of the cross-sectional area of the lower core layer 28 in the direction parallel to the film surface. Preferably there is. The cross-sectional area of the conductive layer 43 in the direction parallel to the film surface is preferably 0.05% or more and 30% or less of the cross-sectional area of the upper shield layer 26 in the direction parallel to the film surface. The reason is the same as the reason for limiting the numerical value of the cross-sectional area of the conductive layer 43 described above.

Next, the shape of the conductive layer 43 will be described below. As shown in FIG. 4, the shape of the cross section in the direction parallel to the film surface of the conductive layer 43 is substantially quadrangular, but the shape of the cross section may be substantially round or the like. Further, the shape of the vertical cross section of the conductive layer 43 is a substantially rectangular shape in FIG. 1, but it may be another shape such as a substantially trapezoidal shape.

Characteristic portions of the thin film magnetic head 21 of FIG. 1 other than the conductive layer 43 will be described below.

As shown in FIG. 1, the conductive layer 47 is also formed in a part between the lower shield layer 23 and the upper shield layer 26.
The lower shield layer 23 and the upper shield layer 26 are electrically connected. The conductive layer 47 may be formed of a non-magnetic conductive material or a magnetic material, but is preferably formed of a non-magnetic conductive material.

Since the lower shield layer 23 and the upper shield layer 26 are electrically connected by the conductive layer 47 as described above, the lower shield layer 23 and the upper shield layer 26 have the same potential, and the lower shield layer 23 and the corrosion resistance of the upper shield layer 26 can be improved,
The shield function of the shield layers 23 and 26 can be appropriately maintained, and the reproduction characteristics can be improved.

Next, the materials of the lower core layer 28 and the upper shield layer 26 will be described below. The lower core layer 28 is preferably formed of a magnetic material having a high saturation magnetic flux density Bs in order to appropriately cope with the increase in recording density. On the other hand, the upper shield layer 26 is preferably formed of a magnetic material having a high magnetic permeability and a low magnetostriction constant in order to improve the shield function. Since the lower core layer 28 and the upper shield layer 26 have different magnetic properties as described above, it is preferable that the lower core layer 28 and the upper shield layer 26 be formed of different materials having the required magnetic properties.

The upper shield layer 26 is made of NiFe-based alloy (permalloy), sendust (Fe-Al-Si-based alloy), or the like. In addition, Co-Zr-Nb (cobalt-zirconium-niobium) type amorphous alloy and Co
It may be formed of a —Hf—Ta (cobalt-hafnium-tantalum) -based amorphous alloy or the like.

The upper shield layer 26 is formed by plating, vapor deposition, sputtering or the like. The lower core layer 28 is formed of a NiFe-based alloy (permalloy), a CoFe-based alloy, a CoFeNi-based alloy, or the like. The lower core layer 28 formed of these materials is formed by electroplating. Alternatively, the lower core layer 28 has a composition formula represented by Fe-MO, and M is Al, Si, Hf, Z.
It may be formed of a soft magnetic material or the like composed of one element or two or more elements out of r, Ti, V, Nb, Ta, W, Mg, or a rare earth element. The lower core layer 28 made of the soft magnetic material is formed by a sputtering method or a vapor deposition method.

In the present invention, when both the lower core layer 28 and the upper shield layer 26 are made of a magnetic material containing Fe and a magnetic element other than Fe, for example, the lower core layer 28 and the upper shield layer 26 are formed. 26 and 26 are both formed of a NiFe-based alloy (permalloy), the Fe composition ratio on the lower core layer 28 side is preferably higher than that on the upper shield layer 26 side. As a result, the lower core layer 28 has a high saturation magnetic flux density, while the upper shield layer 26 has a low saturation magnetic flux density, but it is possible to obtain a high magnetic permeability and a low magnetostriction constant.

In the present invention, as described above, the lower core layer 2
8 and the upper shield layer 26 are made of different materials, the lower core layer 28 and the upper shield layer 26 are partially electrically connected by the conductive layer 43, so that the lower core layer 28 and the upper shield layer 26 are electrically connected to each other. Since the upper shield layer 26 can be made to have the same potential, the corrosion resistance of the lower core layer 28 and the upper shield layer 26 can be improved as compared with the conventional one, and the thin film magnetic head 21 excellent in high recording density can be obtained. Can be formed.

The lower core layer 28 and the upper shield layer 26 may be made of the same magnetic material.

A method of manufacturing the thin film magnetic head 21 shown in FIGS. 1 and 2 will be described below. First, a reproducing MR head h1 having a lower shield layer 23, a magnetoresistive effect element 25, a gap layer 24 and an upper shield layer 26 is formed on the slider 20 shown in FIG.

Next, as shown in FIG. 6 (a partially enlarged vertical sectional view of the thin film magnetic head during the manufacturing process), the upper shield layer 2 is formed.
Insulating layer 27 made of Al ₂ O ₃ or SiO ₂ on 6
Are formed by sputtering or vapor deposition. At this time, it is preferable that the insulating layer 27 is formed with a thickness of 500 Å or more and 10,000 Å or less.

Next, as shown in FIG. 7 (a partially enlarged vertical sectional view of the thin film magnetic head during the manufacturing process), a resist layer 51 is formed on the insulating layer 27, and a hole is formed in the resist layer 51 by exposure and development. 51a is formed. And the hole 51a
The insulating layer 27 exposed from the above is shaved by using the RIE method or the ion milling method to expose the upper surface of the upper shield layer 26 from the hole 51a. Then, the resist layer 51 is removed.

Next, as shown in FIG. 8 (partially enlarged longitudinal sectional view of the thin film magnetic head during the manufacturing process), the upper shield layer 26 exposed from above the insulating layer 27 through the hole 27a formed in the insulating layer 27. The plating base layer 45 is formed on the upper side by a sputtering method or a vapor deposition method. The plating underlayer 45 may be formed of a magnetic material such as a NiFe alloy.
It may be formed of a non-magnetic conductive material such as Cu.

In the process shown in FIG. 9 (a partially enlarged vertical sectional view of the thin film magnetic head during the manufacturing process), the plating underlayer 45 is formed.
The lower core layer 28 is formed by plating. At this time, the plating layer is formed not only on the insulating layer 27 but also on the upper shield layer 26 exposed from the hole 27a of the insulating layer 27. The plating layer formed on the upper shield layer 26 via the plating underlayer 27 functions as a conductive layer 43 for electrically connecting the lower core layer 28 and the upper shield layer 26.

Next, in the step shown in FIG. 10 (partial longitudinal sectional view of the thin film magnetic head during the manufacturing step), the lower core layer 28 is formed.
After forming a magnetic pole layer 34 made of, for example, an organic material, a Gd determining layer 29 and a lower magnetic pole layer 31, a magnetic gap layer 32, and an upper magnetic pole layer 33, a resist is applied from the magnetic pole layer 34 to the lower core layer 28. The lower core layer 2 is formed by forming a layer 48 and then forming a hole 48a in the resist layer 48 formed on the lower core layer 28 by exposure and development.
8 Surface is exposed.

At this time, the front end face 48b of the hole 48a on the recording medium D side is formed on the recording medium side (opposite the Y direction in the drawing) with respect to the front end face 43a of the conductive layer 43 on the recording medium D side. As described above, it is preferable to provide the hole 48 a in the resist layer 48.

Then, as shown in FIG. 11 (partial longitudinal sectional view of the thin film magnetic head during the manufacturing process), the resist layer 48 is formed.
A back gap layer 30 made of a magnetic material is formed by plating in the hole portion 48a formed in.

Before forming the back gap layer 30, a plating base layer may be formed in the hole 48a by sputtering or the like. Since it is the layer 28, the back gap layer 30 can be appropriately grown by plating on the lower core layer 28. Then, the resist layer 48 is removed. By forming the front end face 48b of the hole 48a formed in the resist layer 48 on the recording medium side with respect to the front end face 43a of the conductive layer 43, the front end face 30a of the back gap layer 30 of the conductive layer 43 is formed. It can be formed on the recording medium side (the opposite direction to the Y direction in the drawing) with respect to the front end face 43a. Then, the resist layer 48 is removed.

Next, the insulating base layer 35 shown in FIG. 1 is formed on the magnetic pole layer 34, the lower core layer 28 and the back gap layer 3.
0, and then a first layer is formed on the insulating base layer 35.
After patterning the coil layer 36 and further filling the space between the respective conductors forming the first coil layer 36 with an organic insulating material layer 37 made of an organic insulating material, the organic insulating material layer 37 is formed.
An inorganic insulating material layer 38 made of an inorganic insulating material is formed thereon. Next, the inorganic insulating material layer 38 is flattened using a CMP technique or the like so that the upper surface of the inorganic insulating material layer 38 and the upper surface of the pole layer 34 and the upper surface of the back gap layer 30 are flush with each other, and then the inorganic insulating material layer is formed. Second coil layer 39 on 38
Is patterned, and the second coil layer 39 is covered with an organic insulating material layer 40 formed of an organic material. After forming a hole in the organic insulating material layer 40 on the back gap layer 30, the upper core layer 41 is frame-plated from the back gap layer 30 exposed from the hole to the organic insulating material layer 40. When formed by, the thin film magnetic head having the structure shown in FIG. 1 is completed.

Next, a method for forming the conductive layer 43 from a magnetic material or a non-magnetic conductive material which is a material different from that of the lower core layer 28 as shown in FIG. 3 will be described below with reference to FIG. FIG. 12 is a partially enlarged vertical sectional view during the manufacturing process of the thin film magnetic head according to the present invention.

In the step shown in FIG. 12, first, a conductive layer 43 is formed on the upper shield layer 26 by using a resist layer (not shown), and the resist layer is removed. Next, the insulating layer 2 is formed on the upper shield layer 26 and the conductive layer 43.
7 is formed by a sputtering method, a vapor deposition method, or the like. Then, the insulating layer 27 and the conductive layer 43 are CMP until the upper surface of the insulating layer 27 and the upper surface of the conductive layer 43 are flush with each other.
Cut using technology. Thereby, the conductive layer 4
3 is exposed, and then the insulating layer 2 is exposed as shown in FIG.
After the plating underlayer 46 is formed from 7 to the conductive layer 43 by the sputtering method or the vapor deposition method, the lower core layer 28 is plated on the plating underlayer 46. After that, the same steps as those shown in FIGS. 10 and 11 are performed.

In order to form the conductive layer 43 and the insulating layer 27 on the upper shield layer 26 without using the grinding process such as the CMP technique as in the process of FIG.
Also, the conductive layer 43 and the insulating layer 27 can be formed by using the process shown in FIG.

In the step of FIG. 13, first, the conductive layer 43 is formed on the entire surface of the upper shield layer 26. Next, a resist layer 49 is formed on the conductive layer 43 by exposure and development.
The resist layer 49 may be a lift-off resist layer. Then, the conductive layer 43 not covered with the resist layer 49 is scraped off by ion etching, RIE or the like (the conductive layer 43 in the dotted line portion shown in FIG. 13).
Is scraped off).

As a result, the conductive layer 43 and the resist layer 49 are left on a part of the upper shield layer 26. Here, without removing the resist layer 49, the insulating layer 27 is formed on the upper shield layer 26 where the conductive layer 43 is not formed by a sputtering method or a vapor deposition method in FIG. The insulating material layer 27b forming the insulating layer 27 is also formed on the upper surface of the resist layer 49. At this time, the insulating layer 27 is formed until the position of the upper surface 27a of the insulating layer 27 becomes the same as the position of the upper surface 43b of the conductive layer 43. Thereby, the conductive layer 43
The upper surface 43b of the insulating layer 27 and the upper surface 27a of the insulating layer 27 are flush with each other. However, the upper surface 27a of the insulating layer 27 may not be flush with the upper surface 43a of the conductive layer 43.
It may be located slightly above or below the position of b. That is, the upper surface 43a of the conductive layer 43 and the insulating layer 27
Even if there is some level difference between the upper surfaces 27a of the
There is no problem if the lower core layer 28 can be appropriately plated on the conductive layer 43.

After forming the insulating layer 27, the resist layer 49 is removed, a plating underlayer 46 is formed on the insulating layer 27 and the conductive layer 43, and then a lower core layer is formed on the plating underlayer 46. 28 is formed by plating.

By using the manufacturing process shown in FIGS. 13 and 14, it is possible to omit the grinding process by the CMP technique or the like as in the process of FIG. 12, and it is possible to simplify the manufacturing process.

15 and 16 are process diagrams showing another method of manufacturing the conductive layer 43. 15 and 16
FIG. 6 is a partially enlarged vertical sectional view of a thin film magnetic head during a manufacturing process in the present invention.

In the step shown in FIG. 15, after the upper shield layer 26 is formed by plating, for example, the upper shield layer 2 is formed.
A resist layer 50 is formed on 6 by exposure and development. Next, the surface of the upper shield layer 26 that is not covered with the resist layer 50 is cut to a predetermined depth by ion milling, RIE, or the like (the dotted line portion shown in FIG. 15 is the cut portion). As a result, a protrusion integrated with the upper shield layer 26 is formed under the resist layer 50 from the surface of the upper shield layer 26, and the protrusion functions as the conductive layer 43.

Next, in the step shown in FIG. 16, an insulating layer 27 is formed on the upper shield layer 26 not covered with the resist layer 50 of the present invention by a sputtering method or a vapor deposition method. At this time, the layer 27b of the insulating material forming the insulating layer 27 is also formed on the resist layer 50. It is preferable that the insulating layer 27 is formed until the position of the upper surface of the insulating layer 27 is the same as the position of the upper surface of the conductive layer 43. However, the upper surface of the insulating layer 27 is slightly higher than the upper surface of the conductive layer 43. It may be located on the upper side or the lower side. Then, the resist layer 50 is removed, a plating underlayer is formed from the insulating layer 27 to the conductive layer 43, and then the lower core layer 28 is formed by plating on the plating underlayer.

In the manufacturing process shown in FIGS. 15 and 16, the conductive layer 43 can be formed of the same material as the upper shield layer 26 in the same process, so that the manufacturing process can be simplified.

In order that the back gap layer 30 as shown in FIG. 5 is not formed and the base end portion 41b of the upper core layer 41 is magnetically connected to the upper surface of the lower core layer 28,
First, the first coil layer 36, the organic insulating material layer 37 and the inorganic insulating material layer 38 covering the first coil layer 36 are formed on the lower core layer 28 without using the steps of FIGS. 10 and 11, and the inorganic insulating material layer 38 is further formed. The second coil layer 39 and the organic insulating material layer 40 are formed thereon. Next, the organic insulating material layers 37 and 40
And, a hole portion is formed in the inorganic insulating material layer 38 to penetrate to the surface of the lower core layer 28. Then, by forming the upper core layer 41 from above the organic insulating material layer 40 to the inside of the hole by frame plating, the thin film magnetic head having the structure shown in FIG. 5 is completed.

As shown in FIG. 5, the upper core layer 4
It is preferable that the upper core layer 41 be patterned so that the front end surface 41c of the base end portion 41b of the first unit is located closer to the recording medium D side than the front end surface 43a of the conductive layer 43. In the present invention, the formation position of the conductive layer 43 and the upper core layer 41.
The front end surface 41c of the base end portion 41b of the upper core layer 41 and the front end surface 43 of the conductive layer 43 can be easily adjusted by appropriately adjusting the formation position of the base end portion 41b of each of the above.
It can be located closer to the recording medium D than a.

Further, in the present invention, it is possible to form the lower core layer 28 and the upper shield layer 26 with different materials. A material having a high saturation magnetic flux density Bs is selected as the magnetic material used for the lower core layer 28, and a material having a high magnetic permeability and a low magnetostriction constant is selected as the magnetic material used for the upper shield layer 26. Is preferred.

In the present invention, after forming a protective layer 42 such as Al ₂ O ₃ on the upper core layer 41 shown in FIGS. 1 and 5,
DLC (diamond-like carbon), ta-C (Te) are formed on the front end faces of the thin film magnetic head 21 and the protective layer 42.
The protective layer 44 is formed of one or two or more of the traverse Amorphous Carbon). At this time, it is preferable that the protective layer 44 has a thickness of 0.5 nm or more and 5 nm or less. As a result, it is possible to form a thin film magnetic head that has a small spacing loss and is excellent in high recording density. Further, even if the protective layer 44 is formed thin within the above numerical range, in the present invention, the upper shield layer 26 and the lower core layer 28 are electrically connected by the conductive layer 43, and the upper shield layer 26 and the lower core layer 28 are electrically connected. And are kept at the same potential, the solvent used in the manufacturing process of the thin film magnetic head, the moisture in the air, and the like permeate into the protective layer 44, and the solvent and the moisture penetrate the upper shield layer 26 and the lower portion. Even when reaching the core layer 28, it is possible to appropriately suppress the corrosion of the upper shield layer 26 and the lower core layer 28 as compared with the related art.

As described above, according to the present invention, in the so-called piggyback type thin film magnetic head in which the lower core layer 28 and the upper shield layer 26 are separately formed, the lower core layer 28 and the upper shield layer 26 are formed. Part of the space is the conductive layer 4
3 to form the lower core layer 28 and the upper shield layer 26.
By electrically connecting between the lower core layer 28 and the upper shield layer 26, the lower core layer 28 and the upper shield layer 26 can be made to have the same potential, and a solvent or moisture in the air during the manufacturing process of the thin film magnetic head penetrates into the protective layer 44. Even if the solvent or water reaches the lower core layer 28 and the upper shield layer 26, it is possible to appropriately prevent the lower core layer 28 and the upper shield layer 26 from being corroded as compared with the related art.

Further, in the present invention, since the lower core layer 28 and the upper shield layer 26 are only partially electrically connected by the conductive layer 43, the lower core layer 28 and the upper shield layer 26 at the time of recording and reproducing. Magnetic interference between the two is appropriately suppressed as compared with the case where the lower core layer 28 and the upper shield layer 26 are formed of the same layer, and the piggyback type advantage is appropriately maintained. You can

In order to maintain the superiority of the piggyback type more appropriately, especially when the conductive layer 43 is made of a magnetic material, the front end face 43a of the conductive layer 43 is the front end face of the back gap layer 30. 30a or the front end surface 41c of the base end portion 41b of the upper core layer 41 is formed behind the front end surface 41c in the height direction, whereby the recording magnetic field is transmitted through the conductive layer 43 to the upper shield layer 26. Therefore, magnetic interference between the lower core layer 28 and the upper shield layer 26 during recording and reproducing can be suppressed more appropriately.

Further, in the present invention, it is preferable that the conductive layer 43 is formed of the same material as the lower core layer 28 in the same process, and thus the process of forming the conductive layer 43 can be simplified.

In the present invention, it is also possible to form the lower core layer 28 and the upper shield layer 26 by using different materials, whereby the saturation magnetic flux density Bs of the lower core layer 28 is increased and the core function is improved. Along with increasing the upper shield layer 2
It is possible to increase the magnetic permeability of No. 6 to enhance the shield function.

Even when the lower core layer 28 and the upper shield layer 26 are made of different materials, by forming the conductive layer 43 between the lower core layer 28 and the upper shield layer 26, the lower core layer 28 and the upper shield layer 26 can have the same potential, and the protective layer 44 can be used to reduce spacing loss.
Even if it is formed thin, it is possible to improve the corrosion resistance of the lower core layer 28 and the upper shield layer 26, and it is possible to manufacture a thin film magnetic head suitable for high recording density.

[0128]

According to the present invention described in detail above, in a piggyback type thin film magnetic head in which an MR head for reproduction and an inductive head for recording are completely separated, a lower core layer and an upper shield layer are provided. By electrically connecting a part of the conductive layer with a conductive layer, the lower core layer and the upper shield layer can be made to have the same potential, and a solvent or moisture in the air during the manufacturing process is formed as a protective layer by DLC or the like. Even if it reaches the lower core layer and the upper shield layer through the inside,
The lower core layer and the upper shield layer are less likely to be corroded by the battery effect, and a thin film magnetic head having excellent corrosion resistance compared to the conventional one can be manufactured.

Particularly, in the present invention, the protective layer is formed thin to reduce the spacing loss, and even if the solvent or the like easily reaches the lower core layer or the upper shield layer, the above-mentioned problem of corrosion can be properly solved. A thin film magnetic head that can be solved and can appropriately cope with high recording density can be manufactured.

Further, according to the present invention, even if a conductive layer is formed between the lower core layer and the upper shield layer, magnetic interference between the lower core layer and the upper shield layer can be appropriately suppressed at the time of recording and reproducing, and piggyback can be achieved. It is possible to maintain its superiority as a mold.

[Brief description of drawings]

FIG. 1 is a partial vertical cross-sectional view of a thin-film magnetic head according to a first embodiment of the present invention as viewed from a side facing a recording medium,

FIG. 2 is a partially enlarged vertical sectional view of a thin film magnetic head according to the present invention in which only a structure near a conductive layer is enlarged.

FIG. 3 is a partially enlarged vertical sectional view of a thin film magnetic head according to the present invention in which only the structure near a conductive layer of another form different from that of FIG. 2 is enlarged.

FIG. 4 is a partial plan view of the thin film magnetic head shown in FIG.

FIG. 5 is a partial vertical cross-sectional view of a thin-film magnetic head according to a second embodiment of the present invention as viewed from the side facing a recording medium,

FIG. 6 is a process chart showing the manufacturing process of the thin film magnetic head of the present invention shown in FIGS. 1 and 2;

FIG. 7 is a process chart performed after FIG. 6;

8 is a process chart performed after FIG. 7,

FIG. 9 is a process chart performed after FIG. 8;

FIG. 10 is a process chart performed after FIG. 9;

FIG. 11 is a process chart performed after FIG.

FIG. 12 is a process chart showing the manufacturing process of the conductive layer having the form shown in FIG. 3;

FIG. 13 is a process chart showing a manufacturing process of a conductive layer formed by a method different from that of FIG. 12;

FIG. 14 is a process chart performed after FIG.

FIG. 15 is a process chart showing another method for producing a conductive layer according to the present invention,

16 is a process chart performed after FIG. 15,

FIG. 17 is a partial vertical cross-sectional view of a conventional thin film magnetic head,

FIG. 18 is a partial vertical cross-sectional view of a conventional piggyback thin film magnetic head,

[Explanation of symbols]

21 Thin film magnetic head 26 Upper shield layer 27 Insulation layer 28 Lower core layer 30 back gap layer 30a Front end face (of back gap layer) 41 Upper core layer 41c Front end face (of upper core layer) 43, 47 conductive layer 43a Front end face (of conductive layer) 44 Protective layer 48, 49, 50, 51 Resist layer D recording medium h1 MR head h2 inductive head

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ubata Takahata             1-7 Aki, Otsuka-cho, Yukiya, Ota-ku, Tokyo             Su Electric Co., Ltd. (72) Inventor Hideyuki Hashimoto             1-7 Aki, Otsuka-cho, Yukiya, Ota-ku, Tokyo             Su Electric Co., Ltd. (72) Inventor Yasuhiro Kogawa             1-7 Aki, Otsuka-cho, Yukiya, Ota-ku, Tokyo             Su Electric Co., Ltd. F term (reference) 5D033 BA15 BB43 DA02 DA31                 5D034 BA02 BB08 BB12 DA07

Claims (17)

[Claims] 1. A reproducing head having a lower shield layer, a magnetoresistive effect element, and an upper shield layer, a lower core layer facing the upper shield layer with an insulating layer interposed therebetween, and a magnetic gap layer, A thin-film magnetic head comprising an upper core layer and a recording head having the lower core layer and a coil layer formed between the upper core layer, wherein a part of the upper shield layer and the lower core layer is electrically conductive. A thin film magnetic head characterized by being connected. 2. The thin film magnetic head according to claim 1, wherein the conductive layer is made of a magnetic material. 3. The thin film magnetic head according to claim 2, wherein the conductive layer is formed of the same material as the lower core layer. 4. The thin film magnetic head according to claim 1, wherein the conductive layer is made of a non-magnetic conductive material. 5. The non-magnetic conductive material is NiP, C
The thin film magnetic head according to claim 4, wherein one kind or two or more kinds is selected from u, Al, Cr and Au. 6. The base end portion of the upper core layer is magnetically connected to the lower core layer rearward in the height direction, and the front end face of the conductive layer is higher in the height direction than the front end face of the base end portion. The thin film magnetic head according to claim 1, which is formed on the rear side. 7. The upper core layer and the lower core layer are magnetically connected to each other via a back gap layer at a rear side in the height direction, and a front end face of the conductive layer is higher than a front end face of the back gap layer. The thin film magnetic head according to claim 1, wherein the thin film magnetic head is formed rearward in a direction. 8. The thin film magnetic head according to claim 1, wherein a cross-sectional area of the conductive layer in a direction parallel to the film surface is 1 μm ² or more and 500 μm ² or less. 9. The thin film magnetic head according to claim 1, wherein the lower core layer and the upper shield layer are formed of different magnetic materials. 10. The thin-film magnetic head according to claim 1, wherein a protective layer is formed on the front end face of the thin-film magnetic head, and the thickness of the protective layer is 0.5 nm or more and 5 nm or less. head. 11. The protective layer comprises DLC (diamond-like carbon) and ta-C (Tetrahedral Amorphous).
11. The thin film magnetic head according to claim 10, which is formed of one kind or two or more kinds of carbon). 12. A method of manufacturing a thin-film magnetic head, comprising the following steps. (A) a step of forming a reproducing head having a lower shield layer, a magnetoresistive effect element and an upper shield layer, and (b) forming a conductive layer on a part of the upper shield layer and surrounding the conductive layer. A step of forming an insulating layer,
(C) forming a lower core layer from the insulating layer to the conductive layer, and (d) forming a coil layer and an upper core layer on the lower core layer, and forming the lower core layer, the coil layer,
And a step of forming a recording head having an upper core layer. 13. The method of manufacturing a thin film magnetic head according to claim 12, further comprising the following steps in place of the steps (b) and (c). (E) a step of forming an insulating layer on the upper shield layer, forming a hole in the insulating layer that penetrates to the upper shield layer, and forming a plating underlayer from the inside of the hole to the insulating layer. (F) A step of forming a lower core layer on the plating base layer by plating, and forming a conductive layer integrated with the lower core layer in the hole. 14. The front end face of the base end of the upper core layer magnetically connected to the lower core layer in the step (d), or the lower core layer and the upper core in the step (d). The front end face of the back gap layer formed between the base end portions of the layers,
14. The method of manufacturing a thin-film magnetic head according to claim 12, wherein the conductive layer is formed so as to be located closer to the recording medium than the front end surface of the conductive layer. 15. The method of manufacturing a thin film magnetic head according to claim 12, wherein the lower core layer is formed of a magnetic material different from that of the upper shield layer in the steps (c) and (f). Method. 16. The protective layer is formed on the surface facing the recording medium after the step (d), and the thickness of the protective layer is 0.5 nm or more and 5 nm or less.
16. The method for manufacturing a thin film magnetic head according to any one of 1 to 15. 17. The protective layer is formed of DLC (diamond-like carbon), ta-C (Tetrahedral Amorphous).
17. The thin film magnetic head according to claim 16, which is formed of one kind or two or more kinds of carbon).