JP2001297415A - Magnetoresistive head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure in which the gap between a lower shielding film and an upper shielding film of a magnetism-sensing region of a magnetoresistive head is reduced for the purpose of enhancing surface recording density and furthermore stable insulation between an electrode film and a magnetic shielding film is secured. SOLUTION: In the magneto-resistive head, a lower magnetic shielding film 12 is provided on a substrate and a magnetoresistive sensor film 1 is provided in the magnetism-sensing region on the lower magnetic shielding film 12 via insulating films, and further an electrode film 19 for energizing is connected to a side surface of the magnetoresistive sensor film 1. The thickness of the insulating film between the magneto-resistive sensor film 1 in the magnetism- sensing region and the lower magnetic shielding film 12 is specified to be smaller than the thickness of the insulating film between the electrode film 19 and the lower magnetic shielding film 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording field, for example, a magnetoresistive head used in a magnetic disk drive or the like.

[0002]

2. Description of the Related Art In recent years, a magnetic recording apparatus using a magnetoresistive head (hereinafter referred to as an MR head) has been used as a high-density recording / reproducing head.
It is known that in this MR head, in order to suppress Barkhausen noise and secure an operation region with good linearity, it is necessary to apply a vertical and horizontal bias magnetic field to the magnetoresistive sensor film.

In addition, a narrow track width M corresponding to high-density recording is used.
JP-A-3-125311 discloses an MR head having a narrow track width and excellent sensitivity distribution in a structure in which a magnetoresistive sensor film is disposed only in a magnetically sensitive portion and an electrode is connected to a side surface of the magnetoresistive sensor film. A head is disclosed. This MR head is manufactured by tapering etching a magnetoresistive sensor film using a photoresist as a mask material by an ion milling method in which an incident angle of an ion beam is controlled, and forming an electrode film connected thereto. I have.

[0004]

In the field of magnetic recording,
It is necessary to further increase the areal recording density in the future, but in order to improve the areal recording density, it is necessary to greatly increase the linear recording density in addition to the track density. For this purpose, it is necessary to reduce the gap length of the MR head, that is, the distance between the lower shield film and the upper shield film in the magneto-sensitive area (operating area of the magnetoresistive sensor film).

The prior art described in the above-mentioned Japanese Patent Application Laid-Open No. 3-125311 has a problem that the distance between the lower shield film and the upper shield film in the magneto-sensitive area is not wide enough for high-density recording. If the insulating film of the MR head is thinned, the underlying insulating film is over-etched when the magnetoresistive sensor film is etched by ion milling. It is difficult to ensure insulation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetoresistive head in which a distance between a lower shield film and an upper shield film in a magneto-sensitive area is small and stable insulation between an electrode film and a magnetic shield film is secured. Is to do.

[0007]

In order to achieve the above object, a magnetoresistive head according to the present invention comprises a substrate, a lower magnetic shield film provided on the substrate, and a magnetosensitive film on the lower magnetic shield film. A magnetoresistive sensor film provided in an area through an insulating film, and an energizing electrode film connected to a side surface of the magnetoresistive sensor film, and an insulating film between the magnetoresistive sensor film and the lower magnetic shield film. Is made thinner than the thickness of the insulating film between the electrode film and the lower magnetic shield film.

This magnetoresistive head can have a structure in which a projection is provided on the lower magnetic shield film in the magneto-sensitive area. Such a magnetoresistive head is, for example,
It can be easily manufactured as follows. A lower magnetic shield film is formed on a substrate, the thickness of the lower magnetic shield film is reduced except in a magneto-sensitive area where a magnetoresistive sensor film is formed, and a first insulating film and a second insulating film are formed thereon. An insulating film is formed, and the second insulating film in the magneto-sensitive area is removed to manufacture.

In the above-mentioned magnetoresistive head, the whole or main portion of the insulating film between the electrode film and the lower magnetic shield film in the thickness direction is formed by the insulating film between the magnetoresistive sensor film and the lower magnetic shield film. And different materials. Such a magnetoresistive head can be easily manufactured, for example, as follows. First, a lower magnetic shield film, a first insulating film, and a magnetoresistive sensor film are formed on a substrate, and the magnetoresistive sensor film and the first insulating film other than the magneto-sensitive area are removed. At this time, only the upper part of the first insulating film may be removed, and a part may remain. Next, a second insulating film is formed in a region where the first insulating film has been substantially removed. As described above, if the insulating film is formed twice and made of different materials, the above structure can be easily manufactured.

[Function] By reducing the thickness of the insulating film between the magnetoresistive sensor film and the lower magnetic shield film in the magneto-sensitive area, the distance between the lower shield film and the upper shield film can be reduced, and high-density recording can be achieved. Can respond. On the other hand, by ensuring that the thickness of the insulating film between the electrode film and the lower magnetic shield film is greater than the thickness of the insulating film in the above-described magnetic sensing area, stable insulation between the electrode film and the lower magnetic shield film is ensured. can do.

[0010]

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

<Embodiment 1> FIG. 1 is a structural view of an element portion on a medium facing surface (floating surface) of an MR head according to a first embodiment of the present invention.
2 and 3 are partial structural views showing the manufacturing process. A base film 11 and a lower shield film 12 having a thickness of 2 μm are formed on a substrate 10, and a part of the lower shield film 12, that is, a portion other than a region of the magnetoresistive sensor film 1 to be formed later is thinned. As described above, about 0.5 μm etching is performed by ion milling. The width of the protrusion of the lower shield film 12 formed here is 2 μm, which corresponds to the track width of the recording medium. Usually, the thickness is preferably 1.5 μm to 3 μm. Although an amorphous alloy film of a NiFe film, which is a soft magnetic film, was used for the lower shield film 12, CoN
An amorphous alloy film such as bZr may be used.

Subsequently, as shown in FIG.
First insulating film 13 and second insulating film 1 having a thickness of about 1 μm
7 is formed, and is processed by polishing until the first insulating film 13 is exposed as shown in FIG. 3 and a substantially flat surface is obtained. The thickness of the first insulating film 13 is preferably 0.05 μm to 0.1 μm, and the thickness of the second insulating film 17 is
It is sufficient that the thickness is 0.5 μm or more of the etched thickness. Here, a carbon insulating film (diamond-like carbon film) that is hard and hard to be processed by polishing is used for the first insulating film 13, and Al 2 O 3 is used for the second insulating film 17. May use SiO2 or the like.

FIGS. 4 and 5 are partial structural views showing another method for forming the flat surface. In this case, the first insulating film 13 is partially processed and thinned. Alternatively, an insulating film 27 corresponding to the first insulating film is formed again from the state where it is no longer processed, and has the same function as the structure shown in FIG.

Thereafter, the magnetoresistive sensor film 1 shown in FIG. 1 is formed. This magnetoresistive sensor film 1 is composed of three or more layers as shown in the partial structural view of FIG. In the example of FIG. 6, the soft bias film 14, the separation film 15, the MR film 16
Are continuously formed. Here, the soft bias film 14 is made of NiFeC, which is a generally known high-resistance soft magnetic alloy.
r, NiFeNb, etc., and Ta, MR
As the film 16, a laminated film is sequentially formed using NiFe.

Next, a stencil 31 serving as a mask material as shown in FIG. 6 is formed of photoresist by positioning it at a position where the thickness of the lower shield film 12 is large, and the soft bias film 14 and the isolation film are formed by ion milling. 15, MR
The three layers of the film 16 are etched. At this time, in order to obtain a required side taper angle, the etching is performed while rotating the substrate while setting the incident angle of the ion beam to a large value of 45 degrees or more. Here, in order to surely etch the substrate surface, a part of the substrate surface is over-etched, and the second insulating film 17 is also slightly etched as shown in FIG. Is sufficiently thick, the required thickness of the second insulating film 17 on the lower shield film 12 is secured.

Subsequently, from this state, with the stencil 31 remaining, a vertical bias film 18 for applying a vertical bias to the MR film 16 and an electrode film 19 are continuously laminated as shown in FIG. A hard film of CoCrPt was used for the vertical bias film 18 and Ta / Au / Ta of low resistance was used for the electrode film.
The vertical bias film 18 may be a laminated film of NiMn / NiFe or the like, and the electrode film may be a laminated film of Ta / W / Ta. The film is formed by a normal sputtering method in which the particles adhered to the metal film are large.

In this embodiment, the lower layers of the magnetoresistive sensor film and the longitudinal bias film are substantially flat in any case.

Thereafter, when the stencil 31 is removed, FIG.
Is obtained. Thereafter, as shown in FIG. 9, an upper shield film 21 of the same material as the upper gap film 20 and the lower shield film is formed, and the write gap film 22 shown in FIG.
A coil (not shown), an interlayer insulating film (not shown), a write core 25, a protective film 26, terminals (not shown) and the like are formed to complete the MR head.

FIG. 10 is a partial perspective view of the MR head, showing the positions of the coil 23, the interlayer insulating film 24 and the like.

<Embodiment 2> FIG. 11 is a structural view of an element portion on a medium facing surface (floating surface) of an MR head according to a second embodiment of the present invention, and FIGS. FIG. A base film 11, a lower shield film 12, and a first insulating film 13 are formed on a substrate 10, and then a magnetoresistive sensor film 1 is formed. The material and thickness of the lower shield film 12 and the first insulating film 13 were the same as those of the first embodiment.
The insulating film 13 may be made of an insulating high-purity metal compound such as silicon nitride, alumina, or titania instead of the carbon insulating film.

As shown in FIG. 12, the magnetoresistive sensor film 1 includes a soft bias film 14, an isolation film 15, and an MR film 16.
These layers are formed continuously. The materials described in the first embodiment are used for the soft bias film 14, the separation film 15, and the MR film 16.

Next, a stencil 31 serving as a mask material as shown in FIG. 12 is formed of a photoresist, and the soft bias film 14, the separation film 15, and the MR film are formed by ion milling.
The three layers of the film 16 are etched. At this time, in order to obtain a required side taper angle, the angle of incidence of the ion beam is set to a large value of 45 degrees or more, and the etching is performed while rotating the substrate. Here, in order to surely etch the inside of the substrate surface, a part of the inside of the substrate surface is over-etched. When the first insulating film 13 is thin as shown in FIG. 12, this film is also etched. become.

Subsequently, from this state, with the stencil remaining, as shown in FIG.
The second insulating film 17 having a thickness of m is formed. The film is formed by a method having a high directivity of the insulating film-coated particles 32, for example, an ion beam sputtering method or a collimation sputtering method in which a large number of rectilinear particles are provided. The first insulating film 13 is formed so as to cover part or all of the side surface. In addition, since this film has a thickness necessary for ensuring insulation, a general metal oxide or metal nitride, for example, silicon nitride, alumina, titania, or the like can be used. Thus, since the same mask material is used to form the second insulating film 17, misalignment is unlikely to occur, and the insulation between the electrode film to be formed later and the lower shield film can be reliably ensured.

Thereafter, in this embodiment, as shown in FIG. 14, a longitudinal bias film 18 for applying a longitudinal bias to the MR film 16 is formed. At this time, contact with the side surface of the MR film is ensured. It is preferable that the side surface be cleaned in advance by irradiating the side surface with Ar ions in an oblique direction, and the vertical bias film 18 and the electrode film 19 are continuously laminated. The same material as in the first embodiment is used for the vertical bias film 18 and the electrode film 19.
The formation is performed by an ordinary sputtering method in which the metal film-adhered particles 33 have a large wraparound.

Thereafter, as shown in FIG. 15, the stencil 31 is removed, and the upper gap film 20 and the upper shield film 2 are removed.
1 and a write gap film 22, a coil (not shown), an interlayer insulating film (not shown), a write core 25, a protective film 26, terminals (not shown), etc. shown in FIG.
Complete the head. FIG. 17 is a partial perspective view of the MR head, showing the positions of the coil 23, the interlayer insulating film 24, and the like.

FIG. 16 is a partial structural view in the case where the first insulating film 13 has not been completely etched. In the insulating film under the electrode film 19, most of the thickness is from the second insulating film 17. In this case, it is apparent that a similar insulating effect can be obtained.

[0027]

As described above, in the MR head of the present invention, the distance between the lower shield film and the upper shield film in the magneto-sensitive area can be kept small, and the insulation deterioration between the electrode film and the lower shield film can be reduced. Could be prevented.

[Brief description of the drawings]

FIG. 1 is a structural view of an element portion on a surface facing a medium of an MR head according to a first embodiment of the present invention.

FIG. 2 is a partial structural view showing a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 3 is a partial structural view showing a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 4 is a partial structural view showing another manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 5 is a partial structural view showing another manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 6 is a partial structural view for illustrating a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 7 is a partial structural view for illustrating a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 8 is a partial structural view showing a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 9 is a partial structural view showing a manufacturing process of the MR head according to the first embodiment of the present invention.

FIG. 10 is a partial perspective view of an element portion of the MR head according to the first embodiment of the present invention.

FIG. 11 is a structural diagram of an element portion on a surface facing a medium of an MR head according to a second embodiment of the present invention.

FIG. 12 is a partial structural view showing a manufacturing process of the MR head according to the second embodiment of the present invention.

FIG. 13 is a partial structural view for illustrating a manufacturing process of the MR head according to the second embodiment of the present invention.

FIG. 14 is a partial structural view showing a manufacturing process of the MR head according to the second embodiment of the present invention.

FIG. 15 is a partial structural view showing a manufacturing process of the MR head according to the second embodiment of the present invention.

FIG. 16 is a partial structural view showing another manufacturing step of the MR head according to the second embodiment of the present invention.

FIG. 17 is a partial perspective view of an element portion of an MR head according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Magnetic resistance sensor film, 10 ... Substrate, 11 ... Base film, 1
2 lower shield film, 13 first insulating film, 14 soft bias film, 15 separation film, 16 MR film, 17 second insulating film, 18 vertical bias film, 19 electrode film, 20
... upper gap film, 21 ... upper shield film, 22 ... write gap film, 23 ... coil, 24 ... interlayer insulating film, 25
... Light core, 26 ... Protective film, 27 ... Insulating film, 31 ... Stencil, 32 ... Insulating film adhered particles, 33 ... Metal film adhered particles.

Claims (3)

[Claims] 1. A substrate, a lower magnetic shield film provided on the substrate, a magnetoresistive sensor film provided in a magneto-sensitive area on the lower magnetic shield film via an insulating film, In a magnetoresistive head having a current-carrying electrode film connected to a side surface of a sensor film, the thickness of an insulating film between the magnetoresistive sensor film and the lower magnetic shield film may be smaller than that of the electrode film and the lower magnetic shield film. A magnetoresistive head having a thickness smaller than a thickness of an insulating film between the heads. 2. The magnetoresistive head according to claim 1, wherein said lower magnetic shield film has a convex portion in said magnetosensitive region. 3. The magnetoresistive head according to claim 1, wherein the insulating film between the electrode film and the lower magnetic shield film has a whole or a main portion in a thickness direction of the insulating film and the lower magnetic shield film. A magnetoresistive head comprising a material different from an insulating film between magnetic shield films.