JP2001256612A - Thin-film magnetic head and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin-film magnetic head, capable of properly suppressing occurrence of side fringing. SOLUTION: Relating to an upper core layer 26, recesses 37 are formed in both side faces 26c and 26c in the track width direction, and that part forms a region A. When a place, having the recess 37 formed therein is cui from a direction parallel to a surface which is opposite to a recording medium, its sectional area becomes smaller than that of a region C positioned closer to the opposite surface than to the region A. Thus, the occurrence of side fringing is suppressed properly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film magnetic head for recording used, for example, in a floating magnetic head, and more particularly to a thin-film magnetic head capable of appropriately reducing side fringing and a method of manufacturing the same. .

[0002]

2. Description of the Related Art FIG. 18 is a partial perspective view showing the structure of a conventional thin-film magnetic head (inductive head).

[0005] Reference numeral 1 shown in FIG. 18 is a lower core layer formed of a magnetic material such as permalloy.

As shown in FIG. 18, a gap layer 4 and an upper pole layer 5 have a track width Tw on the lower core layer 1.
And exposed on the surface facing the recording medium. The gap layer 4 and the upper magnetic pole layer 5 are formed with a predetermined length L1 in the height direction (Y direction in the drawing) from the surface facing the recording medium.

Although not shown, insulating layers made of an inorganic insulating material or the like are formed on both sides of the gap layer 4 and the upper magnetic pole layer 5 in the track width direction (X direction in the drawing) and on the height side (Y direction in the drawing). A layer is formed.

A coil layer 13 is spirally patterned on the insulating layer formed on the height side, and the coil layer 13 is formed of an insulating layer (not shown) made of an organic insulating material. Buried by

As shown in FIG. 18, an upper core layer 6 formed by, for example, a frame plating method is formed on the upper magnetic pole layer 5.
Are formed. The upper core layer 6 is magnetically connected to the upper magnetic pole layer 5.

The upper core layer 6 is provided on the coil layer 1.
3, a base end of the upper core layer 6 is magnetically connected to the lower core layer 1, and the lower core layer 1-the upper core layer 6-the upper pole layer 5, a closed magnetic path is formed.

As shown in FIG. 18, the upper core layer 6
Represents a width dimension T in the track width direction (X direction in the drawing) of the upper core layer 6 which is exposed on the surface facing the recording medium.
1 is larger than the width dimension (= track width Tw) of the upper magnetic pole layer 5. The upper core layer 6 has a tip region formed with a constant width T1 in the height direction (the Y direction in the drawing) from the surface facing the recording medium, and a width dimension gradually increased in the height direction from the base end of the tip region. And a rear end region where the width of the rear end increases.

[0010]

However, the configuration of the conventional thin-film magnetic head shown in FIG. 18 has the following problems.

That is, the width dimension T1 of the tip surface 6a exposed on the surface of the upper core layer 6 facing the recording medium is equal to the upper magnetic pole layer 5
Therefore, there is a problem that side fringing easily occurs between the upper core layer 6 and the upper pole layer 5 because the width is larger than the width dimension (= track width Tw).

When side fringing occurs, the areal recording density is reduced, and it is not possible to properly cope with future high recording density.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a thin-film magnetic head capable of appropriately preventing side fringing and a method of manufacturing the same.

[0014]

According to the present invention, there is provided a thin film magnetic head comprising: a lower core layer; a lower magnetic pole layer, a gap layer, and an upper magnetic pole layer laminated in this order on the lower core layer; A recording core that is stacked in the order of the gap layer and the upper magnetic pole layer and is exposed on the surface facing the recording medium;
An insulating layer covering both sides and a height side in the track width direction of the recording core, an upper core layer magnetically bonded on the upper pole layer of the recording core, the lower core layer, the recording core, and the upper core A coil for inducing a magnetic field for recording in the layer, wherein the upper core layer has an area of a cross section parallel to the opposing surface in a region A located on the back side in the height direction from the opposing surface, and It is characterized in that it is smaller than the area of the same parallel cross section in the region located on the opposite surface side than A.

As described above, in the present invention, a region having a smaller sectional area in a direction parallel to the opposing surface than the region A is formed in the upper core layer on the opposing surface side.

That is, in the present invention, since the cross-sectional area of the area C located on the side facing the recording medium is larger than that of the area A, the magnetic flux density B, which is inversely proportional to the cross-sectional area, becomes
The area C is smaller than the area A.

Therefore, the recording magnetic field flowing from the height side to the surface facing the recording medium in the upper core layer becomes smaller in the area C after passing through the area A, so that the recording magnetic field is reduced from the tip end face of the upper core layer to the upper part. The leakage magnetic field generated between the pole layers is reduced, and the occurrence of side fringing can be appropriately suppressed.

In the present invention, the upper core has a tip surface on the side of the facing surface, and when the tip surface is a surface parallel to the facing surface, the area of the tip surface in the region A When the tip surface is not a surface parallel to the facing surface, the area when the tip surface is projected on a surface parallel to the facing surface is larger than the area of the cross section, and the area in the region A is Is preferably larger than the area.

In the present invention, it is preferable that in the region A, at least on the lower surface of the upper core layer, the width dimension in the track width direction is formed smaller than other portions.

Specifically, in the region A, a concave portion vertically penetrating the upper core layer is formed on both side surfaces of the upper core layer opposed to each other in the track width direction. It is preferable that a concave portion extending from the lower surface of the upper core layer to halfway in the height direction of the upper core layer is formed on both sides of the upper core layer facing the track width direction. Thereby, the cross-sectional area of the region A can be made smaller than the cross-sectional area of the region located on the side of the opposing surface, and the occurrence of side fringing can be appropriately suppressed.

In the above case, in the region A, a raised layer of an insulating material having a curved surface that rises from the lower surface of the upper core layer to halfway in the height direction of the upper core layer is formed. It is preferable that the layer is formed over the curved surface of the raised layer from between the raised layers.

It is preferable that the raised layer is formed on a plating underlayer for growing the upper core layer by plating.

The plating underlayer is necessary for forming the upper core layer by plating. If the plating underlayer is formed on the raised layer, the upper core layer is removed from the raised core layer. Continue to grow good plating on the layer,
The surface of the upper core layer on the raised layer rises, and the surface is not flattened. For this reason, the cross-sectional area of the region A of the upper core layer cannot be made appropriately smaller than the cross-sectional area of the region on the facing surface side, and it becomes difficult to appropriately suppress the side fringing. .

Therefore, in the present invention, as described above, the raised layer is formed on the plating underlayer. Thus, the upper core layer is formed on the raised layer by plating growing from the periphery thereof, whereby the surface of the upper core layer can be flattened, and the region A of the upper core layer can be cut off. The area can be made more appropriately smaller than the cross-sectional area of the region located on the facing surface side.

Further, in the present invention, the recording core is prevented from coming off from within the range of the width dimension of the upper core layer narrowed in the region A or from the region in which the range is extended to the facing surface side. Preferably, a relative position in the track width direction between the recording core and the upper core layer is determined. As a result, a recording magnetic field can appropriately flow from the upper core layer to the upper magnetic pole layer, and the occurrence of side fringing can be appropriately suppressed.

Alternatively, in the present invention, the recording core has a tip region having a constant width dimension in the track width direction from the facing surface to a depth side in the height direction, and a height starting from a depth side of the tip region in the height direction. A rear end region in which the width dimension in the track width direction gradually widens toward the back side in the direction, and from within the range of the width dimension of the upper core layer narrowed in the region A, or by moving the range from the facing surface side It is preferable that the relative position of the recording core and the upper core layer in the track width direction is determined so that the rear end region does not deviate from the region extended to the rear. As a result, the contact area between the upper core layer and the upper magnetic pole layer can be increased, and when the region A is formed on the rear end region, recording can be efficiently performed from the region A to the rear end region. A magnetic field can flow, and the recording characteristics can be improved.

Further, in the present invention, the front end surface of the upper core layer is arranged so as to be closer to both sides in the track width direction.
It is preferable to have a curved surface shape that gradually retreats in the height direction. This makes it possible to more appropriately suppress the occurrence of side fringing.

The method of manufacturing a thin film magnetic head according to the present invention comprises the steps of: (a) forming a lower magnetic pole layer from below on a lower core layer;
Laminating the gap layer and the upper magnetic pole layer in order, or laminating the gap layer and the upper magnetic pole layer in order from below, forming a recording core whose width in the track width direction is determined on the surface facing the recording medium, (B) before or after the step (a), forming an insulating layer around the recording core, and further making the upper surfaces of the recording core and the insulating layer flush with each other; (c) the recording core And forming a resist layer on the insulating layer; and (d) forming a cut pattern for forming an upper core layer on the resist layer,
On both sides of the pattern facing the track width direction on the back side in the height direction from the opposing surface, projecting portions projecting into the pattern are formed, and the recording core is positioned within a width dimension narrowed by the projecting portion. Or a step of positioning the recording core in a region where the width dimension range is extended to the facing surface side, and (e) plating a magnetic material in the pattern and removing the resist layer, Forming an upper core layer having a region A in which the width in the track width direction is reduced by the projecting portion.

According to the above-described manufacturing method, a concave portion vertically penetrating the upper core layer can be formed on both side surfaces of the upper core layer opposed to each other in the track width direction, and this portion is the region A. . In the region A, a thin-film magnetic head having a cross-sectional area smaller than that of a region located on the facing surface side than the region A and capable of appropriately suppressing the occurrence of side fringing is manufactured with good reproducibility. Can be.

According to the manufacturing method, the recording core layer can be formed so as not to deviate from the width dimension of the region A in the track width direction, so that the recording magnetic field from the upper core layer can be appropriately applied to the upper part. It is possible to manufacture a thin-film magnetic head that can flow to the pole layer and that can appropriately suppress the occurrence of side fringing.

Alternatively, the method of manufacturing a thin-film magnetic head according to the present invention comprises: (f) laminating a lower magnetic pole layer, a gap layer, and an upper magnetic pole layer in this order on the lower core layer, or a gap magnetic layer and an upper magnetic pole from the bottom. (G) forming a recording core whose width in the track width direction is determined on the surface facing the recording medium by laminating in order of layers, and (g) before or after the step (f), around the recording core. Forming an insulating layer on the recording layer and making the upper surfaces of the recording core and the insulating layer flush with each other; and (h) protruding in the track width direction on the insulating layer on the back side in the height direction from the facing surface. Forming a portion, and at this time, the recording core is located within a width dimension range of a portion where the protruding portion faces, or the recording core is located within a region extending the width dimension range toward the facing surface side. And (i) Forming a resist layer on the recording core and the insulating layer; and (j) forming a cutout pattern for forming an upper core layer on the resist layer, wherein a pattern is formed in the height direction from the facing surface. A step of projecting the protrusion into the pattern from both sides facing the track width direction of the pattern on the back side, and (k) plating a magnetic material in the pattern and removing the resist layer, Forming an upper core layer having a region A in which the width in the track width direction is reduced by the projecting portion.

According to the above-described manufacturing method, a concave portion vertically penetrating the upper core layer can be formed on both sides of the upper core layer opposed to each other in the track width direction. A concave portion extending from the lower surface of the upper core layer to halfway in the height direction of the upper core layer can be formed on both side surfaces facing each other, and this portion is the region A. In the region A, a thin-film magnetic head having a cross-sectional area smaller than that of a region located on the facing surface side than the region A and capable of appropriately suppressing the occurrence of side fringing is manufactured with good reproducibility. Can be.

According to the manufacturing method described above, the recording core layer can be formed so as not to deviate from the width dimension of the region A in the track width direction, so that the recording magnetic field from the upper core layer can be appropriately applied to the upper part. It is possible to manufacture a thin-film magnetic head that can flow to the pole layer and that can appropriately suppress the occurrence of side fringing.

In the present invention, after the step (g), a plating underlayer is formed on the insulating layer. In the step (h), the protrusion is formed on the plating underlayer. Preferably, in the step (k), plating is grown on the plating base layer that appears in a region other than the protruding portion in the pattern of the resist layer.

According to the above-described manufacturing method, after forming the plating base layer on the insulating layer, the protrusion is formed on the plating base layer. The upper core layer is formed, so that the surface of the upper core layer on the protrusion does not become bulged as compared with the surface of the upper core layer in other portions, and the surface of the upper core layer is appropriately planarized. Can be.

Thus, the cross-sectional area of the region A in which the concave portion is formed on the lower surface of the upper core layer can be made smaller than the cross-sectional area of the front end surface, and the thin-film magnetic head can appropriately prevent the occurrence of side fringing. Can be manufactured.

In the present invention, the protrusion formed in the step (h) may be replaced with an insulating material having a curved surface having a height halfway of the height of an upper core layer formed later. In the step (k), plating is grown on the curved surface to form an upper core layer provided with a region A having a recess extending from the lower surface to a halfway height direction. Is preferred.

According to the above-described manufacturing method, a concave portion extending from the lower surface of the upper core layer to halfway in the height direction of the upper core layer can be formed on both side surfaces of the upper core layer opposed to each other in the track width direction. This makes it possible to manufacture a thin-film magnetic head capable of appropriately suppressing the occurrence of side fringing.

[0039]

FIG. 1 is a partial perspective view showing the structure of a thin film magnetic head according to the present invention, FIG. 2 is a front view of the thin film magnetic head shown in FIG. 1, and FIG. 3 is a line 3-3 shown in FIG. 4 and 5 are examples of partial plan views of the thin-film magnetic head according to the present invention.

The thin-film magnetic head shown in FIG. 1 is an inductive head for recording. In the present invention, a reproducing head (MR head) utilizing a magnetoresistive effect is stacked under the inductive head. Is also good.

Reference numeral 20 shown in FIGS. 1 and 2 denotes a lower core layer made of a magnetic material such as permalloy. When a reproducing head is laminated below the lower core layer 20, a shield layer for protecting the magnetoresistive element from noise may be provided separately from the lower core layer 20, or Without providing the shield layer, the lower core layer 20 may function as an upper shield layer of the reproducing head.

As shown in FIGS. 1 and 2, an upper surface 20 of a lower core layer 20 extending from a base end of a lower magnetic pole layer 21 described later.
a may be formed so as to extend in a direction parallel to the track width direction (the X direction in the drawing), or the upper core layer 2
The inclined surfaces 20b, 20b inclined in a direction away from 6 may be formed. By forming the inclined surfaces 20b, 20b on the upper surface of the lower core layer 10, the occurrence of side fringing can be more appropriately reduced.

As shown in FIGS. 1 to 3, a recording core 24 is formed on the lower core layer 20, and the recording core 24 is exposed on a surface facing a recording medium. In this embodiment, the recording core 24 is a so-called track width regulating portion formed with a track width Tw. The track width Tw is preferably formed to be 0.7 μm or less, more preferably 0.5 μm or less.

In the embodiment shown in FIGS. 1 to 3, the recording core 24 has a laminated structure of three layers of a lower magnetic pole layer 21, a gap layer 22, and an upper magnetic pole layer 23. Hereinafter, the pole layers 21 and 23 and the gap layer 22 will be described.
Will be described.

As shown in FIGS. 1 to 3, a lower magnetic pole layer 21, which is the lowermost layer of the recording core 24, is formed on the lower core layer 20 by plating. The lower magnetic pole layer 21
Are magnetically connected to the lower core layer 20, and the lower magnetic pole layer 21 may be formed of the same material as the lower core layer 20 or of a different material. Further, either a single-layer film or a multilayer film may be used. The height of the lower magnetic pole layer 21 is, for example, about 0.3 μm.

As shown in FIGS. 1 to 3, a non-magnetic gap layer 22 is laminated on the lower magnetic pole layer 21.

In the present invention, it is preferable that the gap layer 22 is formed of a non-magnetic metal material and is formed on the lower magnetic pole layer 21 by plating. In the present invention, as the nonmagnetic metal material, NiP, NiPd, NiW, NiM
Preferably, at least one of o, NiRh, Au, Pt, Rh, Pd, Ru, and Cr is selected. The gap layer 22 may be formed of a single-layer film or a multilayer film. May be either. The height of the gap layer 22 is, for example, about 0.2 μm.

Next, on the gap layer 22, an upper magnetic pole layer 23, which is magnetically connected to an upper core layer 26 described later, is formed by plating. The upper magnetic pole layer 23 may be formed of the same material as the upper core layer 26 or may be formed of a different material. Further, either a single-layer film or a multilayer film may be used. The height of the upper magnetic pole layer 23 is, for example, about 2.4 μm to 2.7 μm.

As described above, if the gap layer 22 is formed of a non-magnetic metal material, the lower magnetic pole layer 21, the gap layer 22, and the upper magnetic pole layer 23 can be continuously formed by plating.

In the present invention, the recording core 24 is not limited to the above three-layer structure. The recording core 24 may be formed of a two-layer film including the gap layer 22 and the upper magnetic pole layer 23.

As described above, the lower magnetic pole layer 21 and the upper magnetic pole layer 23 constituting the recording core 24 may be formed of the same material as or different from the core layer to which the respective magnetic pole layers are magnetically connected. Either way, in order to improve the recording density, the lower magnetic pole layer 21 and the upper magnetic pole layer 23 facing the gap layer 22 should be higher than the saturation magnetic flux density of the core layer to which each magnetic pole layer is magnetically connected. It is preferable to have a high saturation magnetic flux density. Since the lower magnetic pole layer 21 and the upper magnetic pole layer 23 have high saturation magnetic flux densities, the recording magnetic field can be concentrated near the gap and the recording density can be improved.

As shown in FIG. 3, a plating base layer 46 is formed between the lower magnetic pole layer 21 and the lower core layer 20.

As shown in FIGS. 1 and 3, the recording core 24 has a length L1 from the surface facing the recording medium in the height direction (Y direction in the drawing).

As shown in FIGS. 1 and 3, the lower core layer 2
A Gd determining insulating layer 27 formed of, for example, a resist or the like is formed on 0, and the surface of the Gd determining insulating layer 27 is formed, for example, in a curved shape. Then, as shown in FIG. 3, an upper magnetic pole layer 23 is formed to extend on the curved surface.

The upper magnetic pole layer 2 is formed on the Gd determining insulating layer 27.
3, the length L1 in the height direction of the upper magnetic pole layer 23 can be increased, so that the volume of the upper magnetic pole layer 23 can be increased, and the upper magnetic pole layer 23 can be formed even in a high recording density. 23 can be reduced, and the recording characteristics can be improved.

As shown in FIGS. 1 and 3, the Gd
The length L2 from the front surface of the insulating layer 27 to the surface facing the recording medium is regulated as the gap depth Gd, and the gap depth Gd greatly affects the electrical characteristics of the thin-film magnetic head. Is set in advance to a predetermined length.

In the embodiment shown in FIGS. 1 to 3, the gap depth Gd is different from the Gd formed on the lower core layer 20.
It is regulated by the position where the insulating layer 27 is formed.

As shown in FIG. 3, the lower core layer 20 is located behind the recording core 24 in the height direction (the Y direction in the drawing).
A coil layer 29 is spirally wound thereover via an insulating base layer 28. The insulating base layer 28 is, for example,
AlO, Al ₂ O ₃ , SiO ₂ , Ta ₂ O ₅ , TiO, Al
N, AlSiN, TiN, SiN, Si ₃ N ₄ , NiO,
It is preferable to be formed of an insulating material made of at least one of WO, WO ₃ , BN, CrN, and SiON.

The pitch between the conductors of the coil layer 29 is filled with an insulating layer 30. The insulating layer 30 is made of AlO, Al ₂ O ₃ , SiO ₂ , Ta ₂ O ₅ , T
iO, AlN, AlSiN, TiN, SiN, Si
_{3 N 4, NiO, WO,} WO 3, BN, CrN, SiON
It is preferable to select from at least one of the following.

As shown in FIG. 2, the insulating layer 30 is formed on both sides of the recording core 24 in the track width direction (the X direction in the drawing), and the insulating layer 30 is formed exposed on the surface facing the recording medium. ing.

As shown in FIG. 3, an insulating layer 31 made of an organic insulating material such as a resist or polyimide is formed on the insulating layer 30, and a second coil layer is formed on the insulating layer 31. 33 is spirally formed.

As shown in FIG. 3, the second coil layer 3
3 is covered with an insulating layer 32 formed of an organic material such as a resist or a polyimide.
An upper core layer 26 made of an iFe alloy or the like is patterned by, for example, a frame plating method.

As shown in FIGS. 1 to 3, a distal end 26 a of the upper core layer 26 is formed on the upper magnetic pole layer 23 by being magnetically connected thereto, and a base 26 b of the upper core layer 26 is formed. Are formed on the lower core layer 20 so as to be magnetically connected on the raised layer 36 made of a magnetic material such as a NiFe alloy. The raised layer 36 may not be formed. In this case, the base end portion 26b of the upper core layer 26 is directly connected to the lower core layer 20.

As shown in FIGS. 1 and 3, the leading end face 26f of the upper core layer 26 on the side facing the recording medium has a width dimension T3, and the width dimension T3 is the track width Tw.
Is bigger than.

Although the thin-film magnetic head shown in FIG. 3 has two coil layers, it may be formed as a single layer. In this case, for example, on the lower core layer 20 and behind the recording core 24 in the height direction, the insulating layer 30 is filled, and a coil layer is formed on the insulating layer 30. Alternatively, the upper core layer 26 is formed along the insulating layer 31 without forming the second coil layer 33 shown in FIG.

Next, the shape of the upper core layer 26 in the present invention will be described in detail. In the present invention, as shown in FIG. 1, concave portions 37, 37 penetrating from the lower surface 26d to the upper surface 26e are formed on both end surfaces 26c, 26c in the track width direction (X direction in the drawing) of the upper core layer 26. .

For this reason, as shown in FIG.
An arbitrary cross-sectional area S1 obtained by cutting the area A in which the regions 7 and 37 are formed in a direction parallel to the surface facing the recording medium is the same as that in the region C located on the side of the facing surface relative to the region A. It is smaller than the area of the parallel cross section.

Further, as shown in FIG. 1, the upper core layer 26 in the present invention has a front end surface 26f on the side facing the recording medium. When the tip surface 26f is a surface parallel to the facing surface, it is preferable that the area of the tip surface 26f is larger than the area of the cross section in the region A.

When the tip surface 26f is not a surface parallel to the facing surface, for example, the tip surface 26f is formed as an inclined surface or a curved surface which is gradually inclined in the height direction (Y direction in the drawing) from the lower surface to the upper surface. In this case, it is preferable that the area of the tip surface 26f projected onto a plane parallel to the facing surface is larger than the area of the cross section in the region A.

Although the recesses 37 are formed on both side surfaces 26c in the track width direction of the upper core layer 26, they may be formed only on one side surface 26c.

The shape of the recess 37 may be any shape. As shown in FIG. 4 and FIG.
7 is formed in a semicircular shape when viewed from above, but may be formed in a square shape when viewed from above, for example.

However, as shown in FIG. 1, when the concave portions 37 are formed on both side surfaces 26c, 26c of the upper core layer 26, the pair of concave portions 37, 37 are formed in the track width direction (X direction in the drawing). It is preferable that the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23.

By the way, from within the range of the width dimension of the upper core layer 26 narrowed in the area A, or from the area where the range is extended to the facing surface side, the recording core 2
Preferably, the relative position in the track width direction between the recording core 24 and the upper core layer 26 is determined so that the recording core 4 does not come off.

In the embodiment shown in FIG.
Is formed with a length L3 in the height direction from the surface facing the recording medium, and has a constant width (= track width Tw). Since the recording core 24 is formed with the track width Tw from the surface facing the recording medium to the base end, the track width Tw can be easily formed within a predetermined dimension value.

On the other hand, in the embodiment shown in FIG. 5, the recording core 24 is moved from the surface facing the recording medium in the height direction (Y in the drawing).
Direction), and a rear end area E whose width in the track width direction gradually increases from the depth side of the front end area in the height direction toward the depth side of the height direction. ing. In this embodiment, since the rear end region E having a width dimension larger than the track width Tw is formed, the upper core layer 26 is joined on the rear end region E, so that the upper core layer 26 The contact area with the recording core 24 can be increased, and the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23.

By the way, as shown in FIG.
When the rear end region E having a wide width is formed in
The recording core 24 and the recording core 24 are fixed so that the rear end region E does not deviate from the range of the width dimension of the upper core layer narrowed in the region A, or from the region in which the range is extended to the facing surface side. It is preferable that the relative position with respect to the upper core layer 26 in the track width direction is determined.

That is, in the present invention, as shown in FIGS. 4 and 5, the area of the lower surface of the region A of the upper core layer 26 to be joined to the recording core 24 (shown by oblique lines) is the same as that of the region A. It is preferable that the area is larger than the area of the upper surface of the recording core 24 at the portion where the recording is performed. This allows the recording magnetic field from the upper core layer 26 to efficiently flow to the upper pole layer 23.

The recording core 24 is preferably formed at the center of the area A within the range of the track width direction (X direction in the drawing). As a result, the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23, and the occurrence of side fringing can be more appropriately prevented.

As described above, in the present invention, the upper core layer 26
Is a cross-sectional area parallel to the facing surface in a region A located on the back side in the height direction from the facing surface with the recording medium.
In the area C located on the side of the opposing surface, the same parallel cross section as described above is smaller. This makes it possible to more appropriately prevent the occurrence of side fringing.

Next, a description will be given of the principle by which the occurrence of side fringing can be appropriately suppressed. The magnetic flux density B is inversely proportional to the cross-sectional area if the magnetic flux φ is constant. That is, the magnetic flux density B increases as the cross-sectional area decreases,
The smaller the cross-sectional area is, the smaller it becomes.

Here, considering the magnetic flux density B in the upper core layer 26 in the present invention, the area A having a smaller cross-sectional area than the area C of the area C located on the facing surface side is considered.
In this case, the magnetic flux density B increases, while in the region C, the magnetic flux density B decreases.

That is, the amount of the recording magnetic field flowing from the region A to the region C decreases, while the recording magnetic field easily flows from the region A of the upper core layer 26 to the upper pole layer 23 (see the arrow in FIG. 3). .

For this reason, on the surface facing the recording medium, the leakage magnetic field between the top end surface 26f of the upper core layer 26 and the upper magnetic pole layer 23 is reduced, and the occurrence of side fringing can be appropriately suppressed. is there. Further, since the recording magnetic field easily flows from the region A to the upper pole layer 23, the upper core layer 26 narrowed in the region A as described above.
So that the recording core 24 does not come off from within the width dimension of
It is preferable that the relative position between the recording core 24 and the upper core layer 26 in the track width direction be determined because the recording characteristics can be improved.

In the present invention, as shown by the dotted line in FIG. 1, the tip end face 26f of the upper core layer 26 moves in the height direction (Y direction in the drawing) toward both sides in the track width direction (X direction in the drawing). It may be formed in a curved surface shape that gradually recedes. As a result, only a part of the leading end surface 26f is exposed from the surface facing the recording medium,
It is possible to more appropriately suppress the occurrence of side fringing.

As shown in FIG. 3, the upper core layer 2
6 may be formed so as to recede from the surface facing the recording medium to the position indicated by the dotted line F, so that the front surface 26f is not completely exposed from the facing surface. This makes it possible to further suppress the occurrence of side fringing.

FIG. 6 is a partial perspective view showing the structure of the thin-film magnetic head according to the second embodiment of the present invention, and FIG. 7 is a partial longitudinal sectional view of the thin-film magnetic head shown in FIG.

The structure of the thin film magnetic head shown in FIGS. 6 and 7 is different from the structure of the thin film magnetic head shown in FIGS. 1 to 5 only in the shape of the tip of the upper core layer 26 except for the other layer structure (shape). ) Is exactly the same.

That is, as shown in FIG. 7, a recording core 24 having a predetermined length L1 in the height direction from the surface facing the recording medium is formed on the lower core layer 20. The core 24 is composed of a three-layer film of the lower magnetic pole layer 21, the gap layer 22, and the upper magnetic pole layer 23, or a two-layer film of the gap layer 22 and the upper magnetic pole layer 23 from below. Further, a Gd determining insulating layer 27 is formed between the lower core layer 20 and the recording core 24, and the length dimension L2 from the surface facing the recording medium to the front surface of the Gd determining insulating layer 27 has a gap depth ( Gd).

As shown in FIG. 7, a coil layer 29 is spirally formed on the lower core layer 20 behind the recording core 24 in the height direction with an insulating base layer 28 interposed therebetween. Further, the pitch between the conductor portions of the coil layer 29 is covered with an insulating layer 30 formed of an inorganic insulating material or the like,
The insulating layer 30 is exposed on the surface facing the recording medium.

On the coil layer 29, an insulating layer 31 made of an organic insulating material or the like is formed.
A second coil layer 33 is spirally formed on 1.

The second coil layer 33 is covered with an insulating layer 32 made of an organic insulating material or the like, and an upper core layer 26 is further formed on the insulating layer 32 by, for example, frame plating. Have been. The upper core layer 2
6 is formed on the upper magnetic pole layer 23 so that the upper core layer 26 and the upper magnetic pole layer 23 are magnetically connected to each other. The upper core layer 26
The base end portion 26 is magnetically connected to a raised layer 36 made of a magnetic material formed on the lower core layer 20.

In the embodiment shown in FIGS. 6 and 7, FIG.
As in the embodiment shown in FIGS.
The area of the cross section parallel to the facing surface in the region A located in the height direction (the Y direction in the drawing) deeper than the facing surface with the recording medium is the region C located in the facing surface side of the region A. Is smaller than the area of the same parallel cross section.

However, the means for forming the region A is different from the thin film magnetic head shown in FIG.

In the embodiment shown in FIG.
Raised layers 40, 40 of an insulating material having a curved surface that rises from the lower surface of the upper core layer 26 to the middle of the upper core layer 26 in the height direction (Z direction in the drawing) are formed.

The raised layers 40 are formed on the insulating layers 30 formed on both sides in the track width direction (X direction in the drawing).

In the region A of the upper core layer 26,
It is formed over the curved surface of the raised layer 40 from between the raised layers 40, 40.

As described above, the raised layers 40, 40 are formed below the upper core layer 26, so that in the region A, the lower surface of the upper core layer 26
At the opposite ends in the track width direction from the lower surface of the upper core layer 26 in the height direction of the upper core layer 26 (Z in the drawing).
(Direction) are formed to extend halfway.

Therefore, when the portion where the concave portion 41 is formed is cut in parallel with the surface facing the recording medium, the cross-sectional area is the same as that in the region C located on the side facing the surface A than the region A. Smaller than the normal cross-sectional area.

The raised layer 41 is made of, for example, Al.
O, Al_TwoO_Three, SiO_Two, Ta_TwoO_Five, TiO, AlN,
AlSiN, TiN, SiN, Si_ThreeN_Four, NiO, W
O, WO _ThreeInsulating materials such as BN, CrN, SiON
Or made of organic insulating material such as resist or polyimide
You.

In the embodiment shown in FIG. 6, two raised layers 41 are formed, but one may be provided.
Further, when two raised layers 41 are formed as shown in FIG. 6, it is preferable that the raised layers 41 be formed in a shape symmetrical in the track width direction (X direction in the drawing). This allows
The two concave portions 41, 41 formed in the upper core layer 26 can also be formed in the same shape, and the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23, and the recording efficiency can be improved. It is.

The raised layer 41 has a curved surface as shown in FIG. 6, but may be formed in a rectangular shape, for example.

Further, the upper core layer 26 is
1, it is necessary to form the upper core layer 26 on the raised layer 41.
It may be formed so as to completely overlap with the upper part.

Also, in the present invention, the recording core 24 does not come off from within the range of the width dimension of the upper core layer 26 narrowed in the region A, or from a region in which the range is extended to the facing surface side. Thus, it is preferable that the relative position of the recording core 24 and the upper core layer 26 in the track width direction is determined.

In the present invention, the raised layer 41 is formed on the insulating layer 30 formed on both sides of the recording core layer 24 in the track width direction. Thus, the recording core 24 can be formed so as not to come off from within the range of the width dimension of the upper core layer 26 or from within a region in which the range is extended to the facing surface side. .

Thus, the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23.

Further, as shown in FIG.
Is the track width T from the surface facing the recording medium in the height direction.
w, and a rear end area E whose width in the track width direction gradually increases from the depth side (the Y direction in the drawing) of the front end area D toward the depth side in the height direction. In this case, from within a range of the width dimension of the upper core layer 26 narrowed in the region A of the upper core layer 26, or from a region in which the range is extended to the facing surface side,
It is preferable that the relative position in the track width direction between the recording core 24 and the upper core layer 26 is determined so that the rear end region E does not deviate.

To achieve this configuration, the recording core 2
When the raised layer 41 is formed on the insulating layer 30 extending on both sides in the track width direction (the X direction in the drawing) of the rear end region 4 of the recording core 24, the region A is placed on the rear end region E of the recording core 24. It is possible to form them so that the end regions E do not come off.

The recording core 24 includes an upper core layer 26
Is preferably formed at the center of the region A in the track width direction (X direction in the drawing) because the recording magnetic field from the upper core layer 26 can efficiently flow to the upper magnetic pole layer 23.

In the case where the upper core layer 26 is formed on the raised layer 31 as in the embodiment shown in FIGS. 6 and 7, the upper core layer 40 is formed under the raised layer 40 as shown in FIG. It is preferable to lay a plating base layer 44 necessary for forming the layer 26.

As shown in FIG. 7, the plating underlayer 44
Are formed on the recording core 24 and the insulating layer 30 formed on both sides of the recording core 24 to the insulating layer 32 covering the second coil layer 33, and are formed on the plating base layer 44. The raised layer 40 is formed.

The upper core layer 26 is formed by plating from the plating base layer 44. However, since the plating base layer 44 is not formed on the build-up layer 40 as described above, the upper core layer 26 is formed. On the layer 40, the upper core layer 26 is formed by plating growth from the periphery thereof, and thus the upper surface 26e of the completed upper core layer 26 is formed.
Is formed by flattening.

On the other hand, when the plating base layer 44 is formed on the raised layer 40, the plating growth is activated also on the raised layer 40, and the upper surface 26e of the completed upper core layer 26 is raised. The portion where the layer 40 is formed rises, and the cross-sectional area of the region A in the direction parallel to the surface facing the recording medium is substantially reduced to the tip surface 26f.
Cannot be made smaller than the area of.

Accordingly, in the present invention, the plating base layer 44 is laid below the raised layer 40 as described above.

Also, in this embodiment, similarly to the embodiment shown in FIGS. 1 to 5, the height of the tip surface 26f of the upper core layer 26 increases toward the both sides in the track width direction (X direction in the drawing). It may be formed in a curved shape that gradually retreats in the direction (Y direction in the figure). Further, as shown in FIG. 7, the leading end surface 26f may be formed so as to recede from the surface facing the recording medium to the position of the dotted line F, and the leading end surface 26f may not be completely exposed from the facing surface.

In the embodiment shown in FIGS. 6 and 7, the magnetic flux density B
Since the area C is smaller than the area A, the recording magnetic field decreases when flowing from the area A to the area C, and the leakage magnetic field between the tip end face 26f and the upper magnetic pole layer 23 decreases.
It is possible to appropriately suppress the occurrence of side fringing. On the other hand, if the area A where the magnetic flux density B is increased is joined on the recording core 24, the recording magnetic field effectively flows from the area A to the upper pole layer 23 side (see the arrow in FIG. 7), and the magnetic flux efficiency Therefore, it is possible to manufacture a thin film magnetic head capable of coping with a higher recording density in the future.

In the embodiment shown in FIGS. 1 and 6, only one region A having a smaller cross-sectional area than the tip surface 26f of the upper core layer 26 is formed, but a plurality of the regions A are formed. It doesn't matter.

According to the present invention, in the region A, it is sufficient that the width dimension in the track width direction is formed at least on the lower surface of the upper core layer 26 to be smaller than other portions.
The present invention is not limited to the embodiment shown in FIGS.

In the present invention, in the region A, the thickness in the height direction (Z direction in the drawing) may be formed to be smaller than the thickness in the region C located on the side opposite to the region A. This also makes it possible to appropriately suppress the occurrence of side fringing.

FIGS. 8 and 9 show a read head (MR) after signals are recorded on a recording medium using the thin film magnetic head (embodiment) shown in FIG. 1 and a thin film magnetic head (comparative example) shown in FIG. 6 is a graph showing a relationship between a position in the track width direction (X direction in the drawing) from the center of the track width Tw and a reproduction output (TAA) at that position when the signal is reproduced using a head. In the experiment, a reproducing head (MR head) having the same shape was used. The zero point on the horizontal axis shown in the graph indicates the center position of the track width Tw in the reproducing head.

As shown in FIG. 8, the reproduction output is maximum at the point 0, that is, at the center of the track width Tw, and the reproduction output (μV) decreases as the distance from the center to the track width direction (X direction in the drawing) increases. At a position about ± 1 μm away from the center of the track width Tw, the reproduction output becomes 0 μV
Becomes

As shown in FIG. 8, it can be understood that side fringing does not occur in the thin film magnetic head of the embodiment.

On the other hand, when the thin-film magnetic head of the comparative example shown in FIG. 9 is used, as in FIG. (ΜV) is reduced, but the reproduction output is improved again at a position about ± 1.1 to 1.3 μm away from the central portion. That is, in the graph shown in FIG.
The reproduction output that rises at a position about ± 1.1 to 1.3 μm away from the central portion is output as side fringing. Thus, as shown in FIG. 9, it can be seen that side fringing easily occurs in the thin film magnetic head of the comparative example.

When the thin-film magnetic head of the embodiment is used, side fringing is unlikely to occur, as described above, because the upper core layer 26 is located on the back side in the height direction from the surface facing the recording medium. The area of the cross section parallel to the opposing surface in the region A located in the region A is smaller than the area of the same parallel cross section in the region C located on the opposing surface side than the region A. In addition, due to the presence of the region A, the recording magnetic field flowing to the region C located on the side opposite to the region A is reduced, and it is possible to appropriately suppress the occurrence of side fringing.

Next, a method of manufacturing a thin film magnetic head according to the present invention will be described below. The thin film magnetic head shown in FIGS. 10 to 14 is a manufacturing process diagram of the thin film magnetic head shown in FIG. 10 to 13 are partial longitudinal sectional views of the thin-film magnetic head, and FIG. 14 is a partial plan view.

As shown in FIG. 10, first, a Gd determining resist layer 27 is formed on the lower core layer 20 and then has a predetermined length in the height direction (Y direction in the drawing) from the surface facing the recording medium. The recording core 24 is formed. The recording core 24
Are sequentially stacked from the bottom in the order of the lower magnetic pole layer 21, the gap layer 22, and the upper magnetic pole layer 23. The recording core 24 may be composed of two layers, the gap layer 22 and the upper magnetic pole layer 23.

It is preferable that the gap layer 22 is formed of a non-magnetic metal material which can be formed by plating. Specifically, the nonmagnetic metal material is NiP, NiPd, Ni
It is preferable to select from one or more of W, NiMo, Au, Pt, Rh, Pd, Ru, and Cr.
Thus, the recording core 24 can be formed by continuous plating.

The width of the recording core 24 in the track width direction (X direction in the figure) is 0.7 μm or less, preferably 0.5 μm or less. Since the width of the recording core 24 in the track width direction is regulated as the track width Tw, the recording core 24 is preferably formed as small as possible. The lower pole layer 21 has a height of about 0.3 μm, the gap layer 22 has a height of about 0.2 μm, and the upper pole layer 23 has a height of 3.0 μm.
m to about 3.3 μm.

Next, as shown in FIG.
And the recording core 24 is filled with an insulating layer 30.
You. As an insulating material for forming the insulating layer 30, inorganic
Preferably, it is an insulating material. Specifically, AlO,
Al_TwoO_Three, SiO_Two, Ta_TwoO _Five, TiO, AlN, Al
SiN, TiN, SiN, Si_ThreeN_Four, NiO, WO, W
O_Three, BN, CrN, SiON
It is preferable to be selected from these.

The reason why the insulating layer 30 is formed of an inorganic insulating material is to make it easy to polish the surface of the insulating layer 30 by a CMP technique to be performed next.

As shown in FIG. 11, the insulating layer 30 is
Polishing is performed from the H line using a CMP technique. Thereby, the surface of the insulating layer 30 is planarized, and the surface of the upper magnetic pole layer 23 is exposed from the surface of the insulating layer 30.

Next, in the step of FIG. 12, a coil layer 45 is spirally patterned on the insulating layer 30 buried on the height side (Y direction in the drawing) with respect to the recording core 24. Is covered with an insulating layer 32 made of an organic insulating material.

Next, in the step shown in FIG. 13, a plating base layer 44 made of a NiFe-based alloy or the like is formed from the recording core 24 to the insulating layer 32.

Next, in the step shown in FIG. 14, after a resist layer 42 is applied on the plating base layer 44, a pattern 42a of the upper core layer 26 is formed on the resist layer 42 by exposure and development.

As shown in FIG. 14, the pattern 42a extends from the surface facing the recording medium in the height direction (Y direction in the drawing).
And a rear end region G whose width in the track width direction increases from the depth side of the front end region F toward the depth side of the height direction. . As shown in FIG. 14, a recording core 24 is formed below the tip region F.

In the present invention, when forming the pattern 42a, the pattern 4a is formed on both side end surfaces of the pattern 42a.
Projections 42b, 42b projecting into 2a are formed. It is preferable that the protrusions 42b are formed in a direction parallel to the track width direction (X direction in the drawing), and are further formed to be symmetrical in the track width direction.

The recording core 24 is positioned within the width dimension narrowed by the protrusions 42b, 42b, or within the area where the width dimension is extended toward the surface facing the recording medium. Position 24.

Further, a tip region D in which the recording core 24 extends in the height direction from the surface facing the recording medium with a track width Tw.
From the both ends of the tip region D in the height direction (Y in the drawing).
Direction), the rear end area E of the recording core 24 is located within the width dimension narrowed by the protrusions 42b, or the width of the rear end area E gradually increases in the width direction. The rear end region E of the recording core 24 is located in a region where the dimensional range is extended toward the surface facing the recording medium.

Then, when a magnetic material is formed by plating in the pattern 42b and the remaining resist layer 42 is removed, a region A shown in FIG. 1 in which the width dimension in the track width direction is narrowed by the protruding portion is formed. The upper core layer 26 can be formed.

That is, according to the manufacturing method of the present invention described above, both end surfaces 26c and 26c of the upper core layer 26 are formed.
The recesses 37, 37 can be formed in c. The area of the cross section parallel to the opposing surface in the region A where the concave portions 37 and 37 are formed is larger than the area of the same parallel cross section in the region C located on the opposing surface side with respect to the region A. It is possible to manufacture a thin-film magnetic head which is reduced in size and can appropriately suppress the occurrence of side fringing.

In addition, according to the above-described manufacturing method, the resist layer 42 is only formed by patterning by exposure and development, and the both end faces 26 of the upper core layer 26 completed by plating are formed.
It is possible to easily and accurately form the concave portions 37, 37 capable of suppressing the occurrence of side fringing in the c, 26c.

Next, a method of manufacturing the thin-film magnetic head shown in FIG. 6 will be described with reference to the process charts shown in FIGS. 15 and 17 are partial longitudinal sectional views of the thin-film magnetic head, and FIG. 16 is a partial plan view of the thin-film magnetic head.

First, after the steps shown in FIGS. 10 to 13 are completed, as shown in FIGS.
The raised layers 40, 40 are formed on 4. The raised layer 40 is made of, for example, AlO, Al ₂ O ₃ , SiO ₂ , Ta ₂ O
₅ , TiO, AlN, AlSiN, TiN, SiN, S
i ₃ N ₄ , NiO, WO, WO ₃ , BN, CrN, SiO
It is formed of an inorganic insulating material such as N or an organic insulating material such as a resist or polyimide.

The position where the raised layer 40 is formed is not limited to the position shown in FIG.
It is necessary to position the recording core 24 within the width dimension of the portion where 0 and 40 face each other, or to position the recording core 24 within a region where the width dimension range is extended toward the facing surface.

The raised layers 40, 40 are formed as shown in FIG.
As shown in FIG. 3, the recording core 24 is formed on the insulating layer 30 formed on both sides of the recording core 24 in the track width direction (X direction in the drawing) via the plating underlayer 44 and a pair of raised layers 40,
40 is preferably formed in a direction parallel to the track width direction. Further, the pair of raised layers 40, 40
Are preferably formed in the same shape and at the same distance from the center of the recording core 24 in the track width direction.

Then, as shown in FIG. 16, a resist layer 43 is applied on the plating base layer 41 and the raised layer 40, and the resist layer 43 is exposed and developed to form the upper core layer 26.
Is formed.

When the pattern 43a is formed, as shown in FIG. 16, the raised layer 40 is inserted into the pattern 43a from both side surfaces facing the track width direction of the pattern 43a on the back side in the height direction from the opposing surface. Let it stick out.

Then, a magnetic material is formed in the pattern 43a by plating, and the remaining resist layer 43 is removed.
The upper core layer 26 having the region A in which the width dimension in the track width direction is narrowed by the raised layer 40 is completed.

In the upper core layer 26, as shown in FIG.
41 are formed, and a portion where the concave portion 41 is formed is a region A.

In addition, according to the above-described manufacturing method, only by forming the raised layer 40, the recesses 4 capable of suppressing the occurrence of side fringing are formed on both side edges of the lower surface of the upper core layer 26.
1, 41 can be easily and accurately formed.

According to the manufacturing method of the present invention, as shown in FIG. 15, after forming a plating base layer 44 necessary for forming the upper core layer 26 by plating growth, a raised layer 40 is formed thereon. are doing.

That is, since the plating base layer 44 is not formed on the raised layer 40, the raised layer 40
No plating is grown on the upper layer, and the plating is gradually grown on the raised layer 40 by plating growth from the portion where the plating base layer 44 is formed. As shown in FIG. 17, the upper surface of the upper core layer 26 is flat. Formed.

On the other hand, the plating base layer 4
When the layer 4 is formed, a plating portion grows on the raised layer 40, so that a raised portion indicated by a dotted line is formed on the upper surface of the upper core layer 26, and the area A faces the recording medium. The cross-sectional area from a direction parallel to the plane cannot be effectively made smaller than the area of the front end face 26f of the upper core layer 26, which is not preferable. Therefore, in the present invention, first, after forming the plated ground layer 41, the plated underlayer 4 is formed.
The raised layer 40 is formed on the upper surface 4.

The present invention is not limited to the manufacturing method described above. For example, a cylindrical protrusion having the same shape as the recess 37 shown in FIG.
It is also possible to form the upper core layer 26 (having a concave portion 37 penetrating from the lower surface to the upper surface) of the shape shown in FIG. In this case, it is necessary to form a plating base layer 44 necessary for growing the upper core layer 26 by plating, and then form the plating base layer on the plating base layer below the protrusion.

In the manufacturing method described above, the upper core layer 2
After the recording core 24 is formed on the lower core layer 20, both sides and the height side in the track width direction of the recording core 24 are filled with the insulating layer 30.
After forming 0, a groove for forming the recording core 24 may be formed in the insulating layer 30, and the recording core may be continuously plated in the groove.

[0155]

According to the present invention described in detail above,
The upper core layer has an area of a cross section parallel to the opposing surface in a region A located on the depth side in the height direction from the opposing surface, and is the same as that in the region located on the opposing surface side than the region A. Since the area is smaller than the area of the parallel cross section, the occurrence of side fringing can be appropriately suppressed.

In the present invention, as the means for forming the region A, for example, a concave portion extending from the lower surface of the upper core layer to a midway in the height direction of the upper core layer is provided at both ends of the upper core layer opposed to each other in the track width direction. Or a recess extending from the lower surface of the upper core layer to halfway in the height direction of the upper core layer. These formations can be achieved by forming a pattern using a resist layer or by forming an upper core layer on an insulating material build-up layer, thereby suppressing the occurrence of side fringing. Can be easily formed with good reproducibility.

Further, in the present invention, the recording core is prevented from coming off from within the range of the width dimension of the upper core layer narrowed in the region A or from the region in which the range is extended to the facing surface side. It is preferable that the relative position of the recording core and the upper core layer in the track width direction is determined, whereby the occurrence of side fringing can be suppressed and the recording magnetic field from the region A can be efficiently moved to the upper part. It is possible to manufacture a thin film magnetic head which can be supplied to the magnetic pole layer and can cope with a higher recording density in the future.

[Brief description of the drawings]

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

FIG. 2 is a partial front view of the thin-film magnetic head shown in FIG. 1,

FIG. 3 is a partial cross-sectional view of the thin-film magnetic head shown in FIG. 2, taken along line 3-3.

FIG. 4 is a partial plan view of a thin-film magnetic head according to the present invention;

FIG. 5 is a partial plan view of a thin-film magnetic head showing another shape;

FIG. 6 is a partial perspective view showing a structure of a thin-film magnetic head according to a second embodiment of the present invention;

7 is a partial longitudinal sectional view of the thin-film magnetic head shown in FIG. 6,

FIG. 8 is a graph showing the relationship between the position from the center of the track width Tw and the reproduction output when a signal is recorded using the thin-film magnetic head of the embodiment and reproduced by the reproduction head;

FIG. 9 is a graph showing the relationship between the position from the center of the track width Tw and the reproduction output when a signal is recorded using the thin-film magnetic head of the comparative example and reproduced by the reproduction head;

FIG. 10 is a partial cross-sectional view showing a method for manufacturing a thin-film magnetic head according to the present invention;

FIG. 11 is a partial cross-sectional view showing a step performed after the step in FIG. 10;

FIG. 12 is a partial cross-sectional view showing a step performed after the step in FIG. 11;

FIG. 13 is a partial cross-sectional view showing a step performed after the step shown in FIG. 12;

14 is a partial plan view showing a step performed after the step in FIG.

FIG. 15 is a partial cross-sectional view of a thin-film magnetic head showing another manufacturing method of the present invention.

16 is a partial plan view showing a step performed after the step in FIG.

FIG. 17 is a partial cross-sectional view showing a step performed after the step in FIG. 16;

FIG. 18 is a partial perspective view showing the structure of a conventional thin film magnetic head.

[Explanation of symbols]

 REFERENCE SIGNS LIST 20 lower core layer 21 lower magnetic pole layer 22 gap layer 23 upper magnetic pole layer 24 recording core 26 upper core layer 26 f tip surface 30 insulating layer 37 concave portion 40 raised layer 41 concave portion 42, 43 resist layer 44 plating base layer A, C region

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kiyoshi Sato 1-7 Yukitani Otsukacho, Ota-ku, Tokyo Alps Electric Co., Ltd. F-term (reference) 5D033 BA08 BA12 CA02 DA04 DA07

Claims (14)

[Claims] A lower core layer, a lower magnetic pole layer, a gap layer from below,
Stacked in the order of the upper magnetic pole layer, or stacked from the bottom in the order of the gap layer and the upper magnetic pole layer, and exposed to the surface facing the recording medium, and both sides and the height side of the recording core in the track width direction. An insulating layer to cover; an upper core layer magnetically bonded on the upper pole layer of the recording core; and a coil for inducing a magnetic field for recording in the lower core layer, the recording core, and the upper core layer. The upper core layer has an area of a cross section parallel to the opposing surface in a region A located on the back side in the height direction than the opposing surface,
The thin-film magnetic head according to claim 1, wherein the area of the parallel section is smaller than the area of the area A on the side of the facing surface. 2. The upper core has a tip surface on the side of the facing surface, and when the tip surface is a surface parallel to the facing surface, the area of the tip surface is the cross section in the region A. If the tip surface is not a surface parallel to the facing surface, the area when the tip surface is projected on a surface parallel to the facing surface is larger than the area of the cross section in the region A. 2. The thin film magnetic head according to claim 1, wherein 3. The thin-film magnetic head according to claim 1, wherein in the region A, at least on a lower surface of the upper core layer, a width dimension in a track width direction is formed smaller than other portions. 4. The thin-film magnetic head according to claim 3, wherein in the region A, a concave portion vertically penetrating the upper core layer is formed on both side surfaces of the upper core layer opposed to each other in the track width direction. 5. In the region A, a concave portion extending from the lower surface of the upper core layer to halfway in the height direction of the upper core layer is formed on both sides of the upper core layer facing the track width direction. The thin-film magnetic head according to claim 3. 6. In the region A, a raised layer of an insulating material having a curved surface that rises from the lower surface of the upper core layer to halfway in the height direction of the upper core layer is formed. 6. The thin-film magnetic head according to claim 5, wherein the thin-film magnetic head is formed over the curved surface of the raised layer from between the raised layers. 7. The thin-film magnetic head according to claim 6, wherein the raised layer is formed on a plating underlayer for growing the upper core layer by plating. 8. The recording so that the recording core does not come off from within a range of the width dimension of the upper core layer narrowed in the region A or from a region in which the range is extended to the facing surface side. 8. The thin-film magnetic head according to claim 3, wherein a relative position in a track width direction between the core and the upper core layer is determined. 9. The recording core has a tip region having a constant width dimension in the track width direction from the facing surface toward the back in the height direction, and a back portion in the height direction starting from the back side of the tip region in the height direction. And a rear end region in which the width dimension in the track width direction gradually widens toward the side, and extending from the range of the width dimension of the upper core layer narrowed in the region A or extending the range to the facing surface side. 8. The thin film magnetic device according to claim 3, wherein a relative position in the track width direction between the recording core and the upper core layer is determined so that the rear end region does not deviate from the inside of the region. head. 10. The thin-film magnetic head according to claim 1, wherein the front end surface of the upper core layer has a curved surface shape that gradually recedes in a height direction toward both sides in a track width direction. . 11. A recording medium comprising: (a) a lower magnetic pole layer, a gap layer, and an upper magnetic pole layer stacked in this order on the lower core layer, or a gap layer and an upper magnetic pole layer in order of bottom; Forming a recording core whose width in the track width direction is determined on the facing surface of (b); and (b) forming an insulating layer around the recording core before or after the step (a); (C) forming a resist layer on the recording core and the insulating layer; and (d) forming an upper core layer on the resist layer. At this time, on both sides of the pattern facing in the track width direction on the inner side in the height direction from the facing surface, projecting portions projecting into the pattern are formed, and narrowed by this projecting portion. Within the width dimension range Locating the recording core or locating the recording core in a region where the width dimension range is extended to the facing surface side; and (e) plating a magnetic material in the pattern, and forming the resist layer Forming a top core layer having a region A in which the width dimension in the track width direction is reduced by the protrusions. (F) a lower magnetic pole layer, a gap layer, and an upper magnetic pole layer are stacked on the lower core layer in this order from the bottom, or a gap layer and an upper magnetic pole layer are stacked in that order from below, and (G) forming a recording core whose width in the track width direction is determined on the opposing surface; (g) forming an insulating layer around the recording core before or after the step (f); Making the upper surface of the core and the insulating layer coplanar; and (h) forming a projecting portion facing the track width direction on the insulating layer on the back side in the height direction from the facing surface; Positioning the recording core within a width dimension range of a portion where the recording core faces each other, or positioning the recording core within a region where the width dimension range is extended toward the facing surface side; On the insulating layer, a resist layer And (j) forming a cutout pattern for forming an upper core layer on the resist layer, and at this time, both side faces facing the pattern in the track width direction on the back side in the height direction from the facing face. Projecting the projecting portion from within the pattern,
(K) forming a magnetic material in the pattern by plating and removing the resist layer to form an upper core layer having a region A in which a width dimension in a track width direction is reduced by the protrusion; A method for manufacturing a thin-film magnetic head, comprising: 13. After the step (g), a plating base layer is formed on the insulating layer, and in the step (h),
The method according to claim 1, wherein the projecting portion is formed on the plating underlayer, and in the step (k), plating is grown on the plating underlayer appearing in a region other than the projecting portion in the pattern of the resist layer. 13. The method for manufacturing a thin film magnetic head according to item 12. 14. The protrusion formed in the step (h) is a raised layer of an insulating material having a curved surface having a height halfway of the height of an upper core layer formed later. And, in the step (k), plating is grown on the curved surface to form an upper core layer provided with a region A having a concave portion extending from the lower surface to an intermediate position in the height direction. 14. The method for manufacturing a thin-film magnetic head according to 12 or 13.