JP2001344708A - Thin film magnetic head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film magnetic head capable of preventing corrosion of a magnetic recording element part and to provide a method for manufacturing the thin film magnetic head. SOLUTION: The thin film magnetic head and the method for manufacturing the thin film magnetic head are characterized by that the thin film magnetic head has two or more layers of magnetic metal films having redox potential different from one another in a head sliding surface facing to a magnetic recording medium of the thin film magnetic head and has a structure in which a local cell is constructed in a position different from the position of a recording gap or a reproducing gap by using the magnetic metal films.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an apparatus for performing high-density recording / reproduction on a magnetic recording medium such as a magnetic disk apparatus (HDD apparatus). And a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, magnetic disk devices (HDD devices)
In recording on a magnetic recording medium such as the one described above, the necessity of improving the processing speed and increasing the recording capacity is increasing, and efforts to increase the recording density are being strengthened. Accordingly, the recording tracks are becoming narrower, and the thin-film magnetic heads themselves are being further miniaturized.

A conventional shield type thin film magnetic head (hereinafter simply referred to as "thin film magnetic head") will be described below with reference to the drawings. 15 and 16 are views showing a conventional magnetic head, and FIG. 17 shows a part of a processing step of the magnetic head.

For example, a thin-film magnetic head used for recording and reproducing a signal on a magnetic recording medium in a magnetic disk drive is often called an MR / inductive composite head as shown in FIG.

In FIG. 16, soft magnetism such as permalloy such as Fe ₂₀ -Ni ₈₀ and Fe ₅₀ -Ni ₅₀ , Co based amorphous magnetic film such as CoNbZr, Sendust, Fe based alloy magnetic film such as granular iron based microcrystalline film, etc. Lower shield layer 161 formed of a material
A lower gap insulating layer 162 is formed using a non-magnetic insulating material such as Al ₂ O ₃ , AlN or SiO ₂ , and a magnetoresistive effect element (AMR (Anisotropic Magnetic
Resistance) element, GMR (Giant Magnetic Resistance)
Element, TMR (Tunneling Magnetic Resistance) element or CMR (Corrosive Magnetic Resistance) element:
Hereinafter, it is referred to as “MR element”. 163 is formed as a stacked film, and a longitudinal bias layer (hereinafter, referred to as a “PM layer”) 164 is formed of a material such as a CoPt alloy on both left and right ends of the MR element 163. Cu,
The electrode lead layer 165 is formed using a material such as Cr or Ta. Here, the electrode lead layer 165 is a PM layer 164.
And the upper surface of the MR element 163 may be partially formed.

Next, the electrode lead layer 165 and the GMR element 1
On the exposed portion 63, a lower gap insulating layer 162 is formed.
Using the same non-magnetic insulating material as in
66 is formed.

Further, a common shield layer 167 is formed on the upper gap insulating layer 166 by using the same soft magnetic material as the lower shield layer 161, and the magnetoresistive thin film magnetic head 160 for reproduction is formed. Is configured.

Next, a recording gap layer 171 is formed on the upper surface of the common shield layer 167 using the same non-magnetic insulating material as the lower gap insulating layer 162, and the recording gap layer 171 is formed.
The upper magnetic pole 17 opposing the common shield layer 167 via the other end 71 and being in contact with the common shield layer 167 at other portions.
2 is formed using the same soft magnetic material as the lower shield layer 161, and the portion where the common shield layer 167 and the upper magnetic pole 172 face each other via the recording gap layer 171 and the upper core (upper magnetic pole) 172. A winding coil 173 insulated from the common shield layer 167 and the upper magnetic pole 172 via an insulating material (not shown) is provided between a portion in contact with the common shield layer 167 and The thin-film magnetic head 170 is formed. Here, the common shield layer 167 is provided with a reproducing magnetoresistive thin film magnetic head section 160.
Shield Function of Recording and Induction Type Thin Film Magnetic Head 170 for Recording
Has the function of also having the lower magnetic pole function.

FIG. 17 is a schematic front view of the magnetic recording medium viewed from the sliding surface side. According to FIG. 17, the MR element 163 is formed on the lower gap insulating layer 162 formed on the upper surface of the lower shield layer 161. MR element 163
A pair of left and right PM layers 164 is formed in contact with both left and right side surfaces of the pair, and a pair of left and right electrode lead layers 165 are formed thereon. Furthermore, an upper gap insulating layer 16
6 is formed, and a common shield layer 167 is further formed thereon. Further, a recording gap layer 171 is formed thereon, and an upper core 172 having a track width 174 is formed thereon.

When a recording current is supplied to the winding coil 173, a recording magnetic field is generated in the upper core 172 and the common shield layer 167 of the recording induction type thin-film magnetic head 170, and the recording magnetic field opposes via the recording gap layer 171. Upper core 1
Leakage magnetic flux is generated between 72 and the common shield layer 167, and a recording signal is recorded on a magnetic recording medium. Further, the magnetic field of the signal recorded on the magnetic recording medium on which the signal is recorded is reproduced by the reproducing magnetoresistive thin film magnetic head section 160,
A reproduction signal corresponding to the resistance change by the R element 163 is detected from the terminal of the electrode lead layer 165.

FIG. 18 shows a part of a normal magnetic head manufacturing process. In general, in a state called a bar 181 obtained by arranging several head elements in a strip shape from the wafer state, lapping is performed so as to have a stripe height of a predetermined MR element, as shown in FIG. 19 which is a front view. Then, a magnetic head having a predetermined shape is manufactured. Thereafter, the exposed lower shield, common shield, upper core, and magnetic metal surface of the magnetoresistive element are protected, and the desired CSS (Contact
In order to obtain (Start Stop) characteristics, a protective film 182 made of DLC, sputtered carbon, CN or the like is provided as shown in FIG. 20 which is a front view. Further, in order to obtain desired flying characteristics, a complicated ABS surface shape is produced from the ABS surface 183 by machining or etching.

In recent years, strong efforts have been made to reduce the size of the device and the thin-film magnetic head associated therewith, and efforts have been made to narrow the recording track width 174 in response to higher recording densities. The conventionally used Fe ₂₀ -Ni ₈₀ permalloy has relatively good corrosion resistance and low magnetostriction, but has drawbacks such as low saturation magnetic flux density, low conductivity, and high eddy current loss at high frequencies. In order to improve recording efficiency, iron-based microcrystalline materials such as Fe ₅₀ -Ni ₅₀ high Bs permalloy and FeN are being used as silo materials and recording core materials in addition to Fe ₂₀ -Ni ₈₀ permalloy. .

Since these magnetic metals are susceptible to corrosion, they are disclosed, for example, in JP-A-62-89210, JP-A-102710, and JP-A-3-37810.
The Japanese Patent Publication No. JP-A-2006-163555 proposes that a metal having a high ionization tendency, such as Al or Zr, be provided near the magnetic head so as to be exposed on the sliding surface.

For example, in JP-A-3-95714 and JP-A-7-37003, when two kinds of magnetic metals are joined to form one layer, the exposed surface of the joint is a local battery. In order to avoid corrosion at the joint, a method has been proposed in which the magnetic metal portion on the base metal side is not exposed to the magnetic surface.

[0015]

However, if a variety of magnetic metal materials are used in the above-described conventional magnetic head, two types of metals having different oxidation-reduction potentials are used in a lapping process for obtaining a desired stripe height. Is exposed. Even though these metals are insulated,
A certain amount of contact is inevitably generated by smear during processing, ESD breakdown, lapping liquid, cleaning liquid, adsorbed water and the like. Therefore, a local battery is formed, and a metal having a low oxidation-reduction potential or a high ionization tendency is likely to be ionized.
There has been a problem that the magnetic properties of the R film deteriorate, the surface roughness increases, and the like.

In particular, at the time of lapping or washing, in the presence of a trace amount of acid or alkali contained in the working fluid or washing fluid, the vicinity of the joint of the metal becomes a local battery, and the oxidation of base metals, particularly iron, is promoted. This caused the head yield to deteriorate.

Also, the method of providing a metal having a high ionization tendency such as Al or Zr on the sliding surface by exposing the metal film having a high ionization tendency such as Al or Zr requires a separate step.
Practical application has been difficult in that the configuration itself is susceptible to corrosion and oxide desorbed powders of these metals are easily generated in the corroded portion.

In addition, a method for preventing the joint from being exposed on the sliding surface is as follows.
It cannot be put to practical use for the following reasons. That is, in order to obtain a metal having a high saturation magnetic flux, an element containing a large number of free electrons such as Fe is generally used, so that the film becomes very active against oxidation and reduction. Therefore, the magnetic metal exposed on the sliding surface for improving the recording characteristics is exposed on the magnetic metal side which is easily corroded. It is extremely difficult to realize a head that exposes only the susceptible magnetic metal to the sliding surface with the combination of the inductive recording head and the read-only magnetoresistive head as described above.

It is an object of the present invention to provide a thin-film magnetic head capable of preventing corrosion of a magnetic recording element portion in order to solve the above-mentioned problems, and a method of manufacturing the same.

[0020]

In order to achieve the above object, a thin film magnetic head according to the present invention comprises two or more layers having different oxidation-reduction potentials in a head sliding surface facing a magnetic recording medium for recording information. And a local battery is formed using the magnetic metal film at a position different from the recording gap or the reproduction gap.

With this configuration, in the process of forming the thin-film magnetic head element, by providing a local battery on the ABS exposed surface during processing, corrosion of the magnetic recording element is prevented, and the magnetic layer of the element is protected by a protective film. Thus, it is possible to prevent the corroded portion due to the local battery from remaining on the magnetic head slider finally.

Further, the thin-film magnetic head according to the present invention comprises:
It is preferable to form a local battery by using a magnetic metal film for cutting off the slider. This is because it is possible to finally eliminate the local battery unit.

Further, the thin-film magnetic head according to the present invention comprises:
It is preferable that the lower shield and the common shield that form the recording gap or the reproduction gap are separated by using the magnetic metal film, and the local cell is formed in the common shield.

Further, the thin-film magnetic head according to the present invention comprises:
It is preferable to form a local battery by using a magnetic metal film in a portion to be processed deeper than the surface of the magnetic recording element on which the ABS processing is performed. This is because the local battery section is finally scraped off.

Further, the thin-film magnetic head according to the present invention comprises:
It is preferable to use Fe ₂₀ -Ni ₈₀ permalloy for a part of the common shield, and to use a lower shield using Co-based amorphous or sendust having a higher oxidation-reduction potential than permalloy.

Also, the thin-film magnetic head according to the present invention
Part of the common shield uses Fe ₂₀ -Ni ₈₀ permalloy, and Co-based amorphous or sendust, which has a higher redox potential than permalloy,
It is preferable to bond Fe ₂₀ -Ni ₈₀ permalloy to a part of the lower shield.

Further, the thin-film magnetic head according to the present invention comprises:
Some opposed the read element of the common shield with Fe ₂₀ -Ni ₈₀ permalloy, upper core bottom of the recording gap, it is preferable to use a Fe ₅₀ -Ni ₅₀ Permalloy to at least one of the common shield top.

Further, the thin-film magnetic head according to the present invention comprises:
It is preferable that a part of the common shield facing the reproducing element is made of Fe ₂₀ -Ni ₈₀ permalloy, and at least one of the lower part of the upper core and the upper part of the common shield constituting the recording gap is made of Fe-based fine particle magnetic metal.

Next, in order to achieve the above object, a method of manufacturing a thin-film magnetic head according to the present invention comprises forming two or more magnetic metal films having different oxidation-reduction potentials on a head sliding surface facing a magnetic recording medium. Having a local battery using a magnetic metal film for the slider cutting margin, and after lapping to obtain a desired stripe height, forming a protective film on the sliding surface and cutting the slider cutting margin. Features.

With this configuration, in the process of forming the thin-film magnetic head element, by providing a local battery on the exposed surface of the ABS during processing, corrosion of the magnetic recording element is prevented, and the magnetic layer of the element is protected by a protective film. Thus, it is possible to prevent the corroded portion due to the local battery from remaining on the magnetic head slider finally.

Further, according to the method of manufacturing a thin film magnetic head of the present invention, the head sliding surface facing the magnetic recording medium is provided with:
Having two or more magnetic metal films having different oxidation-reduction potentials,
A local battery is formed using a magnetic metal film in a portion processed deeper than the magnetic recording element surface by BS surface processing, and after lapping to obtain a desired stripe height, a protective film is formed on a sliding surface, Further, the surface of the local battery portion is removed by performing an ABS surface shape forming process.

Further, the production of the thin-film magnetic head according to the present invention is described.
The construction method is that part of the common shield is Fe ₂₀-Ni₈₀Permalloy
Using a Co-based mole with a higher redox potential than Permalloy
Use a lower shield made of fuzz or sendust.
Is preferred.

Further, a thin-film magnetic head according to the present invention is manufactured.
The construction method is that part of the common shield is Fe ₂₀-Ni₈₀Permalloy
Using permalloy on the lower shield facing the read element
Co-based amorphous or Sendas with higher redox potential
And a part of the lower shield₂₀-Ni₈₀Permalloy
Are preferably joined.

In the method of manufacturing a thin-film magnetic head according to the present invention, the part of the common shield facing the read element may be Fe
_{Using 20-} Ni ₈₀ permalloy, Fe ₅₀ is applied to at least one of the lower part of the upper core and the upper part of the common shield that constitute the recording gap.
It is preferable to use -Ni ₅₀ permalloy.

In the method of manufacturing a thin-film magnetic head according to the present invention, a part of the common shield facing the reproducing element may be Fe
It is preferable to use _20- Ni ₈₀ permalloy and use a Fe-based fine particle-based magnetic metal for at least one of the lower part of the upper core and the upper part of the common shield that constitute the recording gap.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A thin-film magnetic head according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a thin-film magnetic head according to an embodiment of the present invention, and is a schematic front view of the thin-film magnetic head portion viewed from an ABS surface as viewed from a head sliding surface facing a magnetic recording medium.

In FIG. 1, an insulating layer 2 made of Al ₂ O ₃ or the like is formed on a thin film magnetic head slider substrate 1 made of AlTiC or the like, and a CoNbZr amorphous magnetic film is formed thereon. A lower shield layer 3 made of
Further, a lower gap insulating portion 4 is formed thereon using a non-magnetic insulating material such as Al ₂ O ₃ , AlN or SiO ₂ .

Further, although not shown in detail, NiFe
-Based alloy films, free magnetic layers made of Co, CoFe alloy films, etc., non-magnetic conductive layers made of Cu or the like, fixed magnetic layers made of the same ferromagnetic material as the free magnetic layers, and IrMn-based alloy films,
A magnetoresistive element 5 (hereinafter, referred to as a “GMR element”) composed of an antiferromagnetic layer made of a material of α-Fe ₂ O ₃ or NiO-based oxide, such as a FeMn-based alloy film or a PtMn-based alloy film. A pair of left and right vertical bias layers 6 is formed using a hard magnetic material such as a CoPt alloy on the lower gap insulating portion 4 so as to be in contact with both side surfaces of the GMR element 5. A pair of left and right electrode lead layers 7 made of a material such as Cu, Cr, or Ta is formed on the GMR element 6 so as to make at least line contact with the GMR element 5.

An upper gap insulating portion 8 is formed on the upper surface of the GMR element 5 and the upper surface of the pair of left and right electrode lead layers 7 using the same material as the lower gap insulating portion 4. Also, as opposed to the GMR element 5 through the upper gap insulative portion 8, a common shield layer 9 using Fe ₂₀ -Ni ₈₀ Permalloy is formed, the reproducing head portion 10 of the thin-film magnetic head is formed.

Further, on the common shield layer 9, Al
_A recording gap layer 11 is formed using an insulating material such as ₂ O ₃ , AlN, or SiO ₂ , and the recording gap layer 11 faces the common shield layer 9 via the recording gap layer 11, and has a common shield layer at other portions. 9 is made of Fe ₂₀ -Ni ₈₀
It is formed using permalloy.

Although not shown, a winding coil is provided so as to circumnavigate the upper core 12 in a portion in contact with the common shield layer 9, and a recording head section 13 of a thin-film magnetic head is formed. An extra gap layer 14 is provided on the upper or end portion of the electrode lead layer in order to secure sufficient insulation.

In the thin-film magnetic head according to the embodiment of the present invention, the lower shield 3 and the common shield 9 are in contact with each other outside the extra gap, or a thin insulating film such as the lower gap 4 or the upper gap 8 is provided. It is characterized in that a large-area local battery unit 15 composed only of a large area is provided. The location of such a local battery should be at least 10 times the width of the recording or playback track, especially 10
It is desirable that they are separated by 0 times or more. Further, it is desirable that the butting width as viewed from the ABS surface is 10 times or more the track width.

With this configuration, first, corrosion occurs in the local battery unit 15 and the recording element 13 and the reproducing element 10
Can be prevented from occurring in the vicinity of. Originally, defects due to such corrosion should be avoided as much as possible in the magnetic head production process. Completely remove gas, etc.
It is difficult to prevent corrosion, and it is necessary to find the optimal point of the cost for corrosion prevention and the loss cost due to a decrease in yield. According to the present embodiment, even if the corrosion suddenly occurs for the above-mentioned reason, the characteristics of the magnetic recording / reproducing element are not affected at all, so that the loss cost caused by the failure due to the corrosion is greatly reduced. Can be expected.

Next, it is conceivable that the position of the local battery is provided not at the outside of the extra gap layer 14 but at a cutting margin. FIG. 2 is a front view of the thin-film magnetic head in such a case, as viewed from the ABS of the thin-film magnetic head viewed from the head sliding surface facing the magnetic recording medium. FIG. 3 is a schematic view showing one processing procedure for manufacturing the thin-film magnetic head in such a case.

First, the magnetic head 20 is formed, and the local battery 21 is formed not at the outside of the extra gap layer 14 but at the cutting margin 23. In order to achieve such a structure, a bar 32 in which several or more head chips are connected from the wafer 31 is provided.
Cut out a prism called. While monitoring the optical width, electric resistance or inductance of the cut bar 32, a strip height processing step 33 of processing the ABS surface to obtain the bar 22 having a desired stripe height is performed. The stripe height processing step 33 is performed by combining techniques such as cutting, grinding, lapping, polishing, buffing, milling, and etching.

The surface of the bar 22 obtained in this manner is coated with DL
C, after performing a protective film manufacturing process 34 for covering with a protective film such as sputtered carbon, the cutting margin 23 is cut to obtain a single slider 35. The slider 35 thus obtained
However, since the local battery section 21 does not remain on the ABS surface 24, even if corrosion occurs in the local battery section 21, the final characteristics are not affected. Note that the final characteristics here are:
It means a flying characteristic amount of the magnetic head, a CSS (contact start / stop) characteristic indicating a sliding characteristic, an electromagnetic conversion characteristic, and the like.

It is also conceivable to provide a local battery on the ABS trimming surface. FIG. 4 and FIG.
FIG. 4 is a view for explaining an embodiment in such a case, FIG. 4 is a schematic bird's-eye view viewed from the ABS in such a case, and FIG. 5 shows one processing procedure in manufacturing the thin-film magnetic head in such a case. Schematic diagrams are shown, respectively.

In FIG. 4, a lower shield 45 made of a Co-based amorphous film, a common shield 46 made of Fe ₂₀ -Ni ₈₀ permalloy, and a magnetic head 41 made of an upper core 47.
And a local battery 43 is formed on the surface 42 to be subjected to ABS trimming.

First, a bar 52 in which several head chips are connected is cut out from the wafer 51. This bar 52 is
A stripe height processing step 54 for obtaining a bar 53 having a desired stripe height is performed. Bar 5 thus obtained
After performing a protective film manufacturing process 55 for covering the surface of No. 3 with a protective film of DLC, sputtered carbon, SiO ₂ , Cr, etc., an ABS surface process 56 for obtaining desired floating characteristics is performed. This ABS
The surface processing 56 is performed by a technique such as mechanical processing, milling, etching, or the like, and a desired shape and depth are obtained by repeating processing several times.

The magnetic head element 41 remains on the tallest protrusion or the rail portion 48 shown in FIG. 4, and the shaved portion (cavity portion) 42 has a normal processing depth of several tens nm to 10 μm.
It is. This processing may be performed in either the bar state or the slider state. This processing may be performed in two or more steps. A local battery unit 43 is formed in a portion that is cut off by the cavity. The depth of the local battery in the depth direction is desirably smaller than the ABS surface processing depth in order not to leave a erodable portion on the slider in the final processing. Considering the processing accuracy, it is desirably from 0.2 μm to 5 μm. Further, a protective film may be provided on the ABS. Further, the ABS surface processing 56 may be performed in a bar state, or may be performed after cutting the slider.

In the slider 49 thus manufactured, since the local battery 43 is not scraped off and remains, even if corrosion occurs in the local battery 43, the final characteristics are not affected. .

In the above description, an example has been shown in which the lower shield and the common shield are both extended to form a local battery. However, the present invention is not particularly limited to such a structure.

For example, as shown in FIG. 6 which is a schematic front view as viewed from the magnetic ABS, the common shield 61 and the local battery upper part 62 may be separated by a sliding surface and joined to the lower shield 63. . Since current flows through the surface layer of the conductive liquid in the local battery 64, the common shield 61 and the local battery upper portion 62 may be either electrically connected or insulated.

Further, as shown in FIG. 7, which is a schematic front view also viewed from the magnetic ABS surface, the common shield 71 and the local battery upper part 72 are separated by a sliding surface, and
And the local battery lower part 74 may be separated, and the local battery upper part 72 and the local battery lower part 74 may be joined. Local battery 75
Since the electric current flows through the conductive liquid on the surface layer, conduction between the common shield 71 and the local
3 and the lower part 74 of the local battery may be either conductive or insulated.

Further, as shown in FIG. 8, which is a schematic front view also viewed from the magnetic ABS side, a local cell right layer 82 made of the same material as the common shield may be provided outside the lower shield 81. This is the same as the common shield 9 shown in FIG.
4 and the local battery left layer 91 are separated, and the local battery right layer 92 is separated.
May be joined.

6 to 9, the lower shield layer made of a CoNbZr amorphous magnetic film and the Fe ₂₀ -Ni ₈₀
The configuration using a common shield layer made of permalloy is described, but other CoZrCr, CoTaZr, CoTaHf, etc.
-Based amorphous alloy, sendust-based magnetic film, Fe ₂₀ -Ni ₈₀ ,
It goes without saying that the same effect can be obtained even with a combination of magnetic metals having different oxidation-reduction potentials, such as a permalloy magnetic film such as Fe ₅₀ -Ni ₅₀ , and a Fe fine particle based magnetic film such as FeN and Fe based granular films.

Further, removing the local battery portions 64, 75, 83 and 93 by using such a magnetic head manufacturing process is effective in maintaining the final characteristics of the magnetic head.

Further, it is conceivable to provide a large-area local battery section having a local battery upper layer made of the same material as that of the recording core and closely adhered to the common shield, outside the common shield.

For example, in FIG. 10 which is a schematic front view as viewed from the ABS, a lower shield layer 101 made of Fe ₂₀ -Ni ₈₀ permalloy is formed, and a lower gap insulating section, a magnetoresistive element, a vertical bias layer, A reproducing element section 102 including an electrode lead layer and an upper gap insulating section is formed. A common shield layer 103 using Fe ₂₀ -Ni ₈₀ permalloy is formed thereon, and a recording gap layer 104 is formed on the common shield layer 103 using an insulating material such as Al ₂ O ₃ , AlN or SiO _2. , On which the upper core 105
It is formed using Fe ₅₀ -Ni ₅₀ permalloy.

The magnetic head according to this embodiment has a large-area local battery section 107 formed outside the common shield 103 and having a local battery upper layer 106 made of the same material as the recording core and closely adhered to the common shield. . The location of the local battery is preferably at least 10 times the recording track width, and more preferably at least 100 times the recording track width. It is desirable that the butting width as viewed from the ABS surface is 10 times or more the recording track width.

With this configuration, first, corrosion occurs in the local battery unit 107, and it is possible to prevent corrosion near the recording element and the reproducing element. This local battery section is desirably formed at a portion removed by slider cutting, ABS surface processing, or the like.

Further, as shown in FIG. 11, which is a schematic front view as viewed from the ABS, the common shield 111 and the lower part 112 of the local battery are separated by a sliding surface, and the upper part 113 of the local battery is separated.
And the local battery lower part 112 may be joined to form the local battery part 114.

As shown in FIG. 12, which is a schematic front view as viewed from the ABS, in order to prevent saturation of the recording head, the common shield 121 and the upper core 122 are each made into two layers, and the upper part 125 and the upper part Lower part of core 126
Is known to be made of a magnetic layer having a high saturation magnetic flux density. In this case, the common shield lower part 123 and the upper core upper part 1
24 was produced in a small Fe ₂₀ -Ni ₈₀ Permalloy magnetostriction, the top 125 of the common shield, Fe ₅₀ lower 126 of the upper core
-Ni ₅₀ Permalloy or FeN, it is desirable to produce a high saturation magnetic flux density such as iron-based microcrystalline film such as Fe-based granular film. The lower shield 127 is made of a Co-based amorphous film having a lower oxidation-reduction potential than Fe ₂₀ -Ni ₈₀ permalloy and less susceptible to oxidation. Outside the lower shield 127, a local battery upper layer 128 using the same material as the recording core lower part 126 is provided. Large-area local battery unit 129 formed in close contact with the lower shield
Is provided.

With this configuration, first, a local battery 129 is generated between the local battery upper portion 128 which is most susceptible to corrosion and the most stable lower shield 127, and the occurrence of corrosion near the recording element and the reproducing element is prevented. Can be prevented.

Further, as shown in FIG. 13 which is a schematic front view seen from the ABS, a common shield 131 and a local battery lower part 132 made of the same material as the magnetic metal constituting the common shield are separated by a sliding surface. Then, the local battery upper part 133 made of the same material as the magnetic metal constituting the recording gap may be joined to form the local battery part 134.

Further, using the manufacturing process of the magnetic head,
Removing the local battery units 107, 114, 129, and 134 is effective in maintaining the final characteristics of the magnetic head.

Similarly, it is conceivable to provide a large-area local battery section outside the common shield lower layer, in which a local battery upper layer made of the same material as the upper common shield is in close contact with the lower shield. FIGS. 14 and 15 are diagrams for explaining such an embodiment, and FIGS.
5 is a schematic front view as viewed from the ABS.

As shown in FIG.
1. The upper core 142 is made into two layers, and the upper part 145 of the common shield near the recording gap and the lower part 146 of the upper core are made of a layer having a high saturation magnetic flux density. Specifically, the common shield lower part 143 and the upper core upper part 144 are made of Fe ₂₀ -N
Made of i ₈₀ Permalloy, top 145 of common shield,
The lower part 146 of the upper core is made of Fe ₅₀ -Ni ₅₀ permalloy, FeN, Fe
It is manufactured with a high saturation magnetic flux density such as a ferrous microcrystalline film such as a ferrous granular film. Outside the common shield lower layer 143 made of Fe ₂₀ -Ni ₈₀ permalloy, the common shield upper
A large-area local battery unit 148 is provided, in which a local battery upper layer 147 made of the same material as that described above is adhered to the common shield. The bonding width viewed from the ABS surface is 10 times the recording track width.
More than double is desirable. With this configuration, since corrosion occurs from the largest local battery unit, it is possible to prevent corrosion near the recording element and the reproducing element.

Further, as shown in FIG. 15, the common shield lower part 151 and the local battery lower part 152 are separated by a sliding surface, and the local battery upper part 153 and the local battery lower part 152 are joined to form a local battery part 154. Is also good.

Further, removing the local battery sections 148 and 154 by using the above-described magnetic head manufacturing process is effective in maintaining the final characteristics of the magnetic head.

As described above, according to the present embodiment, it is possible to stably produce a magnetic head using a magnetic metal film having a high saturation magnetic flux density but having a problem in corrosion resistance, for example, pure iron or iron-nitrogen alloy. As a result, a magnetic recording device having high recording characteristics, that is, high recording density can be manufactured.

Although the shield type thin film magnetic head has been described above, it goes without saying that the present invention is also effective for a yoke type, bulk type magnetic head and single pole type magnetic head. Further, although the GMR type reproducing head has been exemplified, it goes without saying that the present invention is also effective for an AMR type reproducing head, a TMR type reproducing head, and an inductive type reproducing head.

[0073]

As described above, according to the thin-film magnetic head of the present invention, the thin-film magnetic head element is formed by the same process as the formation of the lower shield layer, the common shield layer and the upper magnetic pole constituting the thin-film magnetic head element. A local battery is provided at a different location from the one above, and after forming the stripe height of the reproducing element, the metal magnetic film is protected with a protective film to remove the local battery that may have been corroded. Thus, it is possible to produce an excellent thin film magnetic head such as improvement in yield.

[Brief description of the drawings]

FIG. 1 is a front view of a thin-film magnetic head according to a first embodiment of the present invention;

FIG. 2 is a front view of a thin-film magnetic head according to a second embodiment of the present invention;

FIG. 3 is a schematic flowchart of a method for manufacturing a thin-film magnetic head according to a second embodiment of the present invention;

FIG. 4 is an overhead view of a thin-film magnetic head according to a third embodiment of the present invention;

FIG. 5 is an explanatory diagram of a method of manufacturing a thin-film magnetic head according to a third embodiment of the present invention.

FIG. 6 is a front view of a thin-film magnetic head according to a fourth embodiment of the present invention;

FIG. 7 is a front view of a thin-film magnetic head according to a fourth embodiment of the present invention;

FIG. 8 is a front view of a thin-film magnetic head according to a fourth embodiment of the present invention;

FIG. 9 is a front view of a thin-film magnetic head according to a fourth embodiment of the present invention;

FIG. 10 is a front view of a thin-film magnetic head according to a fifth embodiment of the present invention;

FIG. 11 is a front view of a thin-film magnetic head according to a fifth embodiment of the present invention;

FIG. 12 is a front view of a thin-film magnetic head according to a fifth embodiment of the present invention;

FIG. 13 is a front view of a thin-film magnetic head according to a fifth embodiment of the present invention;

FIG. 14 is a front view of a thin-film magnetic head according to a sixth embodiment of the present invention;

FIG. 15 is a front view of a thin-film magnetic head according to a sixth embodiment of the present invention;

FIG. 16 is a perspective view of a conventional thin-film magnetic head element.

FIG. 17 is a front view of a conventional thin-film magnetic head element.

FIG. 18 is an explanatory diagram of a method for manufacturing a conventional thin-film magnetic head element.

FIG. 19 is an explanatory view of a conventional method for manufacturing a thin-film magnetic head element.

FIG. 20 is an explanatory diagram of a conventional method for manufacturing a thin-film magnetic head element.

[Explanation of symbols]

1 substrate 2 insulating layer 3, 45, 63, 73, 81, 94, 101, 127,
131, 161 Lower shield layer 4, 162 Lower gap insulating part 5, 163 Magnetoresistance effect element (MR element, GMR element) 6, 164 Vertical bias layer 7, 165 Electrode lead layer 8, 166 Upper gap insulating part 9, 46, 61, 71, 103, 111, 167 Common shield layer 10, 102, 121, 141, 160 Thin-film magnetic head reproducing head section 11, 104, 171 Recording gap layer 12, 47, 105, 172 Upper cores 13, 122, 142, 170 Thin-film magnetic head recording head section 14 Extra gap 15, 21, 43, 64, 75, 83, 93, 107,
114, 129, 134, 148, 154 Local battery section 20, 41 Magnetic head element 22, 32, 52, 53, 181 Bar 23 Cutting margin 31, 51 Wafer 33, 54 Stripe height processing step 34, 55 Protective film manufacturing step 35 , 49 Slider 42 ABS processing part 56 ABS surface processing step 62, 72, 106, 113, 128, 133, 14
7, 153 Local battery upper layer 74, 112, 132, 152 Local battery lower layer 82, 92 Local battery right layer 91 Local battery left layer 123, 143, 151 Common shield lower layer 124, 144 Upper core upper layer 125, 145 Common Shield upper layer 126, 146 Upper core lower layer 173 Recording coil 174 Recording width 182 Protective film 183 ABS surface

Claims (14)

[Claims] 1. A head sliding surface facing a magnetic recording medium on which information is recorded has two or more magnetic metal films having different oxidation-reduction potentials, and the magnetic metal film is provided at a position different from a recording gap or a reproducing gap. A thin film magnetic head comprising a local battery using a film. 2. The thin-film magnetic head according to claim 1, wherein the local battery is formed by using the magnetic metal film at a position where a slider is cut. 3. The thin-film magnetic head according to claim 1, wherein a lower shield and a common shield forming a recording gap or a reproducing gap are separated by using the magnetic metal film, and the local battery is formed in the common shield. 4. The thin-film magnetic head according to claim 1, wherein the local battery is formed by using the magnetic metal film in a portion processed deeper than a magnetic recording element surface on which an ABS surface is processed. 5. A part of the common shield is made of Fe ₂₀ -Ni ₈₀ permalloy, and has a redox potential higher than that of the permalloy.
The thin-film magnetic head according to any one of claims 1 to 4, wherein a lower shield using a system amorphous or sendust is used. 6. A part of the common shield is made of Fe ₂₀ -Ni ₈₀ permalloy, and a Co-based amorphous or sendust having a higher oxidation-reduction potential than the permalloy is used on a surface of the lower shield facing the reproducing element. 5. The thin-film magnetic head according to claim 1, wherein Fe ₂₀ -Ni ₈₀ permalloy is bonded to the thin film magnetic head. 7. A part of the common shield facing the reproducing element is made of Fe ₂₀ -Ni ₈₀ permalloy, and is provided on at least one of the lower part of the upper core and the upper part of the common shield constituting the recording gap.
5. The thin-film magnetic head according to claim 1, wherein Fe ₅₀ -Ni ₅₀ permalloy is used. 8. A part of the common shield facing the reproducing element is made of Fe ₂₀ -Ni ₈₀ permalloy, and is provided on at least one of the lower part of the upper core and the upper part of the common shield constituting the recording gap.
The thin-film magnetic head according to any one of claims 1 to 4, wherein a magnetic metal based on Fe-based fine particles is used. 9. A local battery is formed by providing two or more magnetic metal films having different oxidation-reduction potentials on a head sliding surface facing a magnetic recording medium, and using the magnetic metal films to cut off a slider. A lapping process for obtaining a desired stripe height, forming a protective film on the sliding surface, and cutting off the slider cutting margin. 10. A head sliding surface opposed to a magnetic recording medium, comprising two or more magnetic metal films having different oxidation-reduction potentials, wherein said portion is formed deeper than a magnetic recording element surface by ABS surface processing. After configuring the local battery using a magnetic metal film and finishing the lapping process to obtain a desired stripe height, a protective film is formed on the sliding surface, and an ABS surface shape forming process is further performed to form the local battery portion. A method for manufacturing a thin-film magnetic head, comprising removing a surface layer. 11. A part of the common shield is made of Fe ₂₀ -Ni ₈₀ permalloy, and has a higher oxidation-reduction potential than the permalloy.
The method for manufacturing a thin-film magnetic head according to claim 9 or 10, wherein a lower shield using Co-based amorphous or Sendust is used. 12. A part of the common shield is made of Fe ₂₀ -Ni ₈₀ permalloy, and a Co-based amorphous or sendust having a higher oxidation-reduction potential than the permalloy is used on the lower shield facing the reproducing element. Fe ₂₀ -Ni ₈₀
The method for manufacturing a thin-film magnetic head according to claim 9 or 10, wherein permalloy is bonded. 13. A part of the common shield facing the reproducing element is made of Fe ₂₀ -Ni ₈₀ permalloy, and Fe ₅₀ -Ni ₅₀ permalloy is used for at least one of a lower part of an upper core constituting a recording gap and an upper part of the common shield. Item 11. The method for manufacturing a thin-film magnetic head according to Item 9 or 10. 14. A part of the common shield facing the reproducing element is made of Fe ₂₀ -Ni ₈₀ permalloy, and at least one of the lower part of the upper core constituting the recording gap and the upper part of the common shield is made of a Fe-based fine particle magnetic metal. Item 11. The method for manufacturing a thin-film magnetic head according to Item 9 or 10.