JPH1166513A - Magnetic head and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic head in which a defect such as a disconnection or the like is not caused at a coil formed by forming a thin film and in which the coil is operated satisfactorily and to provide a manufacturing method, for the magnetic head, in which a yield is enhanced greatly. SOLUTION: A magnetic head 1 is provided with a pair of magnetic core half bodies 2, 3 in which metal magnetic thin films 5 are formed obliquely on a substrate 4 and in which butting faces are planarized by filling a glass 6. End faces of the metal magnetic thin films 5 are butted via a nonmagnetic material, and a magnetic gap G is formed. A recess for coil formation is formed on the butting face of at least one out of the magnetic core half bodies 2, 3, and a thin-film coil is formed inside the recess for coil formation. In this case, in at least one out of the magnetic core half bodies 2, 3, the metal magnetic thin films 5 are cut so as to correspond to the recess for coil formation, a protective film 12 is formed so as to cover at least a cut face 9, and the protective film 12 is filled with the glass 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head having a thin film coil and having a magnetic path formed by a metal magnetic thin film, and a method of manufacturing the same.

[0002]

2. Description of the Related Art For example, in a magnetic recording / reproducing apparatus such as a video tape recorder, digital recording for digitizing and recording a signal in order to improve image quality has been promoted. The recording frequency has been increased.

By the way, as magnetic recording density and recording frequency increase, magnetic heads mounted on magnetic recording / reproducing apparatuses are required to have high output in a high frequency range and low noise. . For example, a so-called composite-type metal film is formed by forming a metal magnetic thin film on a ferrite material, which has been widely used as a magnetic head for a VTR, and then performing winding.
In-gap type magnetic heads have large inductance, and output per inductance decreases,
It is difficult to sufficiently cope with digital image recording which requires a high frequency and a high density because the output is low in a high frequency range.

[0004] Under such circumstances, a so-called thin film type magnetic head manufactured in a thin film forming process is being studied as a magnetic head compatible with high frequency.

This thin-film magnetic head is formed by preparing a pair of magnetic core halves 100 as shown in FIG. 16 and joining the pair of magnetic core halves via a non-magnetic material. The magnetic core half 100 has an inclined surface 101a.
And a slope 101 of the substrate 101
a, and a glass 103 formed so as to embed the metal magnetic thin film 102 therein. On one main surface of the magnetic core half 100, a front butting portion 104 and a rear butting portion 105 each of which exposes a part of the metal magnetic thin film 102 are formed.
Between the front butting portion 104 and the rear butting portion 105, a substantially rectangular coil forming concave portion 106 centering on the rear butting surface 105 is formed.

Although not shown, a coil is formed in the coil forming recess 106 in a thin film forming step. One end of the coil is connected to the terminal 107, and the coil is wound around the rear butting surface 105.

[0007] The magnetic head is formed by abutting a pair of magnetic core halves 100 via a non-magnetic material. At this time, the pair of magnetic core halves 100 becomes a magnetic head by abutting the front butting portions 104 and the rear butting portions 105 via a non-magnetic material.

[0008]

By the way, in the above-mentioned thin-film type magnetic head, the concave portion 108 is formed by grinding the metal magnetic thin film 102 formed in a flat shape on the inclined surface 101a. To form a front butting surface 10
4 and the rear butting surface 105. That is,
When the recess 108 is formed by grinding, the cross section of the metal magnetic thin film 102 is exposed at a portion between the front butting surface 104 and the rear butting surface 105.

When manufacturing the above-described magnetic head, the molten glass is also filled in the cross section between the front butting surface 104 and the rear butting surface 105, and the glass 103 is formed. At this time, the high-temperature molten glass is applied to the front butting surface 104 and the rear butting surface 105.
When the space between the cross sections is filled, a reaction occurs with the cross section. As a result, bubbles are generated from this cross section.

As a result, when the molten glass is cooled to form the glass 103, bubbles exist in the glass 103 immediately above the portion between the front butting surface 104 and the rear butting surface 105.

On the other hand, in the portion between the front butting surface 104 and the rear butting surface 105, the coil forming recess 106 is formed as described above. As a result, some of the air bubbles located immediately above the portion between the front butting surface 104 and the rear butting surface 105 are exposed on the surface of the coil forming recess 106. For this reason, the coil-forming concave portion 106 has a hole 109 on the surface where the bubble is exposed.

When a thin film is formed in the coil forming recess 106, as described above, if the hole 109 is formed in the coil forming recess 106, the hole 109 is formed.
There is a possibility that disconnection may occur in the coil at the portion.
As described above, the conventional magnetic head often causes a defect in the coil, and the yield is extremely low.

Accordingly, the present invention solves the above-mentioned problems of the conventional magnetic head, and provides a magnetic head in which a coil formed by forming a thin film has no defects such as disconnection and operates well, and a large yield. It is an object of the present invention to provide a method of manufacturing a magnetic head with improved characteristics.

[0014]

A magnetic head according to the present invention which has achieved the above-mentioned object has a metal magnetic thin film formed obliquely on a substrate and a mating surface flattened by filling with glass. A pair of magnetic core halves is provided, and a magnetic gap is formed by abutting end faces of the metal magnetic thin films via a non-magnetic material, and a coil forming recess is formed on an abutting surface of at least one magnetic core half. In the magnetic head formed and formed with a thin-film coil in the coil-forming recess, at least one of the magnetic core halves is formed by cutting a metal magnetic thin film corresponding to the coil-forming recess. A protective film is formed so as to cover the cut surface, and the protective film is filled with glass.

In the magnetic head according to the present invention configured as described above, a protective film is formed on a portion of the metal magnetic thin film where the cut surface is formed. Therefore, in the magnetic head, the cut surface does not come into contact with the glass, and the metal magnetic thin film on the cut surface does not react with the glass. Thereby, in this magnetic head, the metal magnetic thin film reacts with the glass, so that no bubbles are generated from the cut surface, and as a result, there are no bubbles in the glass located immediately above the cut surface. State. In other words, the position directly above the cutting surface is substantially filled with only glass.

Therefore, in this magnetic head, irregularities due to bubbles are not formed on the surface of the coil forming concave portion formed by grinding the glass. That is, in this magnetic head, the surface of the coil forming concave portion is highly flattened. Therefore, in this magnetic head, the thin-film coil can be formed in the coil-forming recess having a high degree of flatness without causing a defect such as disconnection in the thin-film coil.

On the other hand, a method of manufacturing a magnetic head according to the present invention, which has solved the above-mentioned problems, comprises forming a pair of magnetic core halves by forming a metal magnetic thin film on a substrate having an inclined surface.
A metal magnetic thin film formed on at least one of the magnetic core halves is subjected to a cutting process corresponding to the concave portion for forming a coil, and a protective film is formed covering a cut surface formed on the metal magnetic thin film. Then, the substrate is filled with glass to flatten the butted surface, a concave portion for forming a coil is formed in the glass facing the flattened butted surface, a thin film coil is formed in the concave portion for forming the coil, and a pair of magnetic cores is formed. The halves are joined and integrated via a non-magnetic material so that the end faces of the metal magnetic thin films abut each other to form a magnetic gap.

According to the method for manufacturing a magnetic head according to the present invention having the above-described structure, the protective film is formed on the cut surface formed on the abutting surface of the metal magnetic thin film. Therefore, in this method, when filling the molten glass,
There is no contact between the glass material and the metal magnetic thin film on the machined surface. For this reason, according to this method, even when the molten glass material is filled, no bubbles are generated in the glass immediately above the cut surface.

Therefore, according to this method, even when the coil-forming concave portion is formed by grinding, the surface of the coil-forming concave portion is flattened without forming irregularities due to bubbles. That is, according to this method, it is possible to form a coil-forming concave portion having a highly planarized surface. For this reason, according to this method, a thin film coil can be formed without generating defects such as disconnection.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a magnetic head and a method of manufacturing the same according to the present invention will be described in detail with reference to the drawings.

As shown in FIGS. 1 and 2, the magnetic head 1 according to the present invention is formed by joining a pair of magnetic core halves 2 and 3 via a gap material G made of a nonmagnetic material. . The pair of magnetic core halves 2 and 3 include a non-magnetic substrate 4 and
The metal magnetic thin film 5 formed diagonally on the non-magnetic substrate 4
And a glass 6 formed on the non-magnetic substrate 4 so as to cover the metal magnetic thin film 5. Also,
At least one of the pair of magnetic core halves 2 and 3 is provided with a coil 7 for exciting or detecting an induced electromotive voltage. In the magnetic head 1, the metal magnetic thin film 5 forms a magnetic core in a state where the pair of magnetic core halves 2 and 3 are joined via the gap material G. The magnetic head 1 reproduces or reproduces a signal magnetic field recorded on the magnetic recording medium by sliding the magnetic recording medium in a direction indicated by an arrow A in FIG. 2 in a state where the magnetic core halves 2 and 3 are joined. A signal magnetic field is recorded on a magnetic recording medium.

In the magnetic head 1, a contact width regulating groove 8 is formed in order to adjust a contact area with the magnetic recording medium. The contact width regulating grooves 8 are formed on both side surfaces of the magnetic head 1 in parallel with the sliding direction A of the magnetic recording medium. In this magnetic head 1, the sliding surface of the magnetic recording medium is formed in an arc shape in order to adjust the contact state with the magnetic recording medium.

In the magnetic head 1, the metal magnetic thin film 5 is formed obliquely on the non-magnetic substrate 4 at a predetermined angle. Therefore, when the pair of magnetic core halves 2 and 3 are joined via the gap material G, the magnetic cores are arranged obliquely with respect to the sliding direction of the magnetic recording medium.
The metal magnetic thin film 5 is configured so that its cross-sectional shape is substantially U-shaped. That is, the metal magnetic thin film 5 has the concave portion 9 at the substantially central portion of the end surface on the side where the magnetic core halves 2 and 3 are joined.

For this reason, the metal magnetic thin film 5 has a front butting surface 10 and a rear butting surface 11 which are divided and exposed at the joining surfaces 2A and 3A of the magnetic core halves 2 and 3, respectively. In the magnetic head 1, the front butting surface 10 of one magnetic core half 2 and the front butting surface 10 of the other magnetic core half are butted with a gap material G therebetween to form a magnetic gap. . In this magnetic head 1, the rear butting surface 11 of one magnetic core half 2 and the rear butting surface 11 of the other magnetic core half 3 abut each other to form a back gap.

On the other hand, in the magnetic head 1, a protective film 12 is formed on the concave portion 9 of the metal magnetic thin film 5 configured as described above. That is, in the magnetic head 1, the concave portion 9 does not come into direct contact with the glass 6, and the concave portion 9 and the glass 6 are arranged via the protective film 12. As will be described in detail later, the protective film 12 is formed so as to cover a concave portion formed on the metal magnetic thin film 5 by a grinding process, thereby preventing bubbles from being generated from the concave portion 9.

In the magnetic head 1, the metal magnetic thin film 5 is formed of three metal magnetic layers 5 through the nonmagnetic layer 5A.
B are laminated. The magnetic head according to the present invention is not limited to the configuration in which the three metal magnetic layers 3B are stacked as shown in the present embodiment.
That is, the magnetic head 1 according to the present invention may have, for example, a single-layer metal magnetic thin film, or may have several tens of metal magnetic layers 5B.

In the magnetic core halves 2 and 3, the non-magnetic substrate 4 is made of, for example, a MnO—NiO-based non-magnetic material, but is not limited to this. Calcium titanate, barium titanate, zirconium oxide ( Zirconia), alumina, alumina titanium carbide, SiO ₂ , Zn ferrite, crystallized glass, high hardness glass and the like may be used. The metal magnetic thin film 5 is made of, for example, Fe-
It is made of a metal magnetic material such as an Al-Si alloy (Sendust), but is not limited to this. Fe-Al alloy, Fe-Si
-Co alloy, Fe-Ga-Si alloy, Fe-Ga-Si
-Ru alloy, Fe-Al-Ge alloy, Fe-Ga-Ge
Alloy, Fe-Si-Ge alloy, Fe-Co-Si-Al
An alloy or a crystalline alloy such as an Fe—Ni alloy may be used. Alternatively, the metal magnetic thin film 5 is made of Fe, Co,
Alloy consisting of one or more elements of Ni and one or more elements of P, C, B, Si, or an alloy containing Al, Ge, Be, Sn, In, Mo, W, Ti, M
metal-metalloid amorphous alloys typified by alloys containing n, Cr, Zr, Hf, Nb, etc .;
It may be made of an amorphous alloy such as a metal-metal amorphous alloy containing a transition metal such as Hf or Zr and a rare earth element as main components.

As the protective film 12, for example, an inorganic oxide is preferably used. Examples of the inorganic oxide include oxides such as Si, Al, Fe, Ti, and Cr.

Further, in the magnetic head 1, the coils 7 are formed on the pair of magnetic core halves 2 and 3, respectively. The coil 7 has a coil-forming recess 13 formed on the joining surfaces 2A and 3A of the pair of magnetic core halves 2 and 3, and a thin film is formed in the coil-forming recess 13. One end 7A of the coil 7 on the center side is connected to the coil connection terminal 14. The coil 7 has a rear abutting surface 11 with the coil connection terminal 14 as a base end.
Is formed so as to draw a circle around the center.

The coil connecting terminals 14 formed on the pair of magnetic core halves 2 and 3 are formed in the coil forming recesses 13 and serve as substantially the center of the coil 7. It is formed in the vicinity. The coil connection terminal 14 is connected to the joint surface 2 of the pair of magnetic core halves 2 and 3.
The heights are adjusted so as to be flush with A and 3A. In the magnetic head 1, when the pair of magnetic core halves 2 and 3 are joined, the pair of coil connection terminals 14 are also joined. This allows
In the magnetic head 1, when the pair of magnetic core halves 2 and 3 are joined, the pair of coils 7 are electrically connected.

In the magnetic head 1, when joining the pair of magnetic core halves 2 and 3, metal diffusion bonding, which will be described in detail later, is used. In this case, a non-magnetic conductive material such as gold is formed on the bonding surfaces 2A and 3A, and they are abutted. As a result, the pair of front butting surfaces 10 are butted via the non-magnetic conductive material to form a magnetic gap. That is, in the magnetic head 1, as the above-mentioned gap material G, a non-magnetic conductive material used in metal diffusion bonding is used.

The other end of the coil 7 on the opposite side is drawn out to the side opposite to the magnetic gap. The other end of the coil 7 is connected to an external connection terminal 15. The external connection terminal 15 is formed by burying a conductive material such as copper in a terminal groove 16 formed at a predetermined depth in the width direction of the pair of magnetic core halves 2 and 3. . The external connection terminals 15 can be electrically connected to the outside and the coil 7 by being exposed to the side surface of the magnetic head 1. The pair of external connection terminals 15 are formed at different positions in the pair of magnetic core halves 2 and 3 so as not to cause a short circuit when the pair of magnetic core halves 2 and 3 are joined. ing.

In the magnetic head 1 according to the present embodiment configured as described above, when reproducing a magnetic signal recorded on the magnetic recording medium, a signal magnetic field from the magnetic recording medium is applied to the vicinity of the magnetic gap. Is done. When the direction of the applied signal magnetic field changes, the direction of the magnetic flux flowing through the magnetic core changes. As a result, electromagnetic induction occurs in the magnetic head 1, and a predetermined current flows through the coil 7.

When a magnetic signal is recorded on a magnetic recording medium using the magnetic head 1, a predetermined current is supplied to the coil 7. In the magnetic head 1, a predetermined magnetic flux flows through the magnetic core by the magnetic field generated from the coil 7. As a result, in the magnetic head 1, a leakage magnetic field is generated across the magnetic gap. Magnetic head 1
Records a magnetic signal by applying this leakage magnetic field to a magnetic recording medium.

By the way, in the magnetic head 1, the recess 9
A protective film 12 is formed thereon. Details will be described later,
When manufacturing the magnetic head 1, the concave portions 9 are formed by grinding the metal magnetic thin film 5. For this reason,
The surface of the concave portion 9 is a cross section of the metal magnetic thin film 5,
When the molten high-temperature glass comes into contact, a reaction occurs. In such a case, bubbles are generated from the surface of the concave portion 9.

However, in the magnetic head 1, since the protective film 12 is formed on the concave portion 9, the surface of the concave portion 9 does not come into direct contact with the glass. That is, in the magnetic head 1, the contact between the surface of the concave portion 9 and the glass is prevented by the protective film 12. For this reason, in the magnetic head 1, no bubbles exist in the glass immediately above the recess 9.

As a result, in the magnetic head 1, no irregularities due to bubbles are formed on the surface of the coil-forming concave portion 13. That is, in the magnetic head 1, the surface property of the coil forming recess 13 is good.
For this reason, in the magnetic head 1, the coil forming recess 1
The coil 7 having a thin film formed on the surface of the coil 3 is good due to the surface property of the coil forming recess 13. Therefore, the magnetic head 1 always has a good current flowing through the coil 7 and has good recording / reproducing characteristics.

Next, a method for manufacturing a magnetic head according to the present invention will be described in detail with reference to the drawings. Here, a manufacturing method for manufacturing the above-described magnetic head 1 will be described.

In the magnetic head 1 according to the present embodiment, a plurality of magnetic core halves 2 and 3 are formed on the same substrate. The magnetic head 1 is formed by bonding a pair of the substrates and separating the substrates into individual magnetic heads 1.

First, to manufacture the magnetic head 1,
As shown in FIG. 3, a substantially flat substrate 21 is prepared. This substrate 21 is to be the non-magnetic substrate 4 of the magnetic head 1, and is made of a non-magnetic material such as MnO-NiO. The substrate 21 has, for example, a thickness of about 2 mm and a length and a width of about 30 mm.

Next, as shown in FIG.
The first groove processing is performed on the one side surface 21A of the first groove. In the first groove processing, a plurality of magnetic core forming grooves 24 are formed in parallel with one side surface 21A by a grindstone or the like so as to have an angle of, for example, about 45 °. A plurality of inclined surfaces 24A are formed by the magnetic core forming grooves 24 formed by the first groove processing.

The inclined surface 24A formed here preferably has an inclination angle of about 25 to 60 ° with respect to the plane of the substrate, but is preferably 35 to 50 ° in consideration of the pseudo gap and track width accuracy.
A degree of inclination angle is more preferable. Also, here, this first
The magnetic core forming groove 24 formed by the groove processing described above is formed to have a depth of 130 μm and a width of 150 μm.

Next, as shown in FIG. 5, a metal magnetic thin film 5 made of the above-described material is formed on the surface of the substrate 21 on which the inclined surface 24A is formed. In this film forming step, the metal magnetic thin film 5 is formed so as to have a uniform film thickness on the surface on which the inclined surface 24A is formed. At this time, the metal magnetic thin film 5 is formed such that three layers of metal magnetic materials are stacked via a nonmagnetic layer. This film forming step
For example, it is performed by a PVD method such as a magnetron sputtering method or a CVD method.

Further, the metal magnetic thin film 5 is not limited to the one having a plurality of metal magnetic layers, but may have a structure composed of a single metal magnetic layer.

In this embodiment, the metal magnetic thin film 5
Is composed of a plurality of layers, for example, Fe-Al-
Alumina 0.15μ on Si alloy (Sendust) 5μm
m are alternately stacked and three layers of Fe—Al—Si alloy layers are provided. When the metal magnetic thin film 5 is composed of a plurality of layers, alumina, SiO 2
Materials such as ₂ and SiO are used alone or in combination.
The thickness of the non-magnetic layer must be large enough to provide insulation between the adjacent metal magnetic layers.

Next, as shown in FIG.
A second groove is formed on the surface on which is formed the groove substantially perpendicular to the magnetic core forming groove 24. In this second groove processing,
Separation grooves 26 formed for separating into magnetic cores of a desired size, and winding grooves 27 for forming the coil forming recess 13 in each magnetic core separated by the separation grooves 26
Are formed.

Here, the separation groove 26 is formed by connecting the magnetic core to the substrate 2.
1 is a groove for forming each magnetic core by magnetically separating the magnetic core in the front-rear direction, and forming a closed magnetic path in each magnetic core. Although two separation grooves 26 are formed in the example of FIG. 6, the separation grooves 26 need to be provided by the number of rows of the magnetic core halves 2 and 3 to be formed. The separation groove 26 is formed so as to have a depth dimension such that the metal magnetic thin film 5 is completely cut in order to magnetically separate the magnetic cores arranged side by side in the front-rear direction. There is. Specifically, the separation groove 2
6 is 150 μm deeper than the bottom of the magnetic core forming groove 24,
That is, the depth is 280 μm.

On the other hand, as shown in FIG.
In the magnetic head 1 described above, a concave portion 9 formed in the metal magnetic thin film 5 is formed. Therefore, the winding groove 27 forms a magnetic core having the front butting surface 10 and the rear butting surface 11, and has a depth dimension such that the metal magnetic thin film 5 is not cut to form the coil forming recess 13. It must be formed with Therefore, when the winding groove 27 is formed, the cross section of the metal magnetic thin film 5 is exposed on the surface of the concave portion 9.

The shape of the winding groove 27 is determined in accordance with the lengths of the front butting surface 10 and the rear butting surface 11. Here, the width is about 140 μm. The length of the abutment surface 10 is about 300 μm, and the length of the rear abutment surface 11 is about 85 μm. The winding groove 27 may have such a depth that the metal magnetic thin film 5 is not cut. However, if the winding groove 27 is too deep, there is a possibility that the magnetic path length increases and the efficiency of magnetic flux transmission is reduced. Although the depth of the winding groove 27 depends on the thickness of the coil 7 formed in a step described later, it is, for example, about 20 μm. Further, the shape of the winding groove 27 is not limited,
Here, for example, the side surface on the front butting surface 10 side is an inclined surface 27A of about 45 °. Thus, the metal magnetic thin film 5 has a structure in which the magnetic flux is concentrated on the front butting surface 10 side, thereby improving the sensitivity.

Next, as shown in FIG. 8, the protective film 12 is formed in the winding groove 27. The protective film 12 is made of the above-described inorganic oxide, and is formed so as to cover substantially the entire surface of the winding groove 27. Thereby, the cross section of the metal magnetic thin film 5 exposed by forming the winding groove 27 can be covered.

At this time, as shown in FIG. 9, the protective film 12 may be formed so as to cover the entire portion of the metal magnetic thin film 5 exposed to the outside. That is, in this method, the protective film 12 may be formed so as to cover at least the surface of the concave portion 9.

Next, as shown in FIG. 10, the magnetic core forming groove 24, the separation groove 26 and the winding groove 27 are formed as described above, and the main surface of the substrate 21 on which the protective film 12 is formed is formed. The molten low melting point glass 29 is filled. And
One main surface filled with the low melting point glass 29 is subjected to a surface flattening process.

At this time, in this method, since the protective film 12 is formed so as to cover at least the surface of the concave portion 9, the low-melting glass 29 does not contact the surface of the concave portion 9. In other words, the low melting point glass 29 does not come into contact with the cross section of the metal magnetic thin film 5. That is, in this method, the surface of the recess 9 and the low-melting glass 29 are prevented from coming into contact with each other by forming the protective film 12.

Therefore, in this method, the high-temperature low-melting glass does not react with the surface of the recess 9. For this reason, the generation of bubbles due to the reaction with the low melting point glass is prevented from the surface of the concave portion 9. Thus, no bubbles are present in the low-melting glass 29.

Next, as shown in FIG. 11, a terminal groove 30 is formed by grinding using a grindstone or the like. The terminal groove 30 is formed so as to be located immediately above the above-described separation groove 26, and has a width of about 200 μm and a depth of about 100 μm. Then, a good conductor such as Cu is filled in the terminal groove 30 by a plating method or the like.
After that, a flattening process is performed. The good conductor such as Cu filled in the terminal groove 30 becomes the external connection terminal 15 in the magnetic head 1 described above.

Next, as shown in FIG. 12, a coil forming recess 13 in which the coil 7 is formed as a thin film is formed. The coil forming recess 13 is formed in a substantially rectangular shape with the rear abutting surface 11 substantially at the center, and is formed by etching a portion excluding the rear abutting surface 11. In addition, the coil-forming recess 13 is provided with a groove 1 reaching the terminal groove 30 from one end thereof.
3A.

At this time, in this method, as described above, by forming the protective film 12, no bubbles are present in the low melting point glass 29 immediately above the concave portion 9. In the case where air bubbles are present in the low melting point glass 29, when the coil forming recess 13 is formed, irregularities due to the air bubbles may be formed on the surface thereof. However, in this method, no air bubbles are generated in the low-melting glass 29, so that no irregularities are formed in the coil-forming concave portions 13, and the coil-forming concave portions 13 having good surface properties are formed.
Can be formed.

Next, as shown in FIG. 13, a thin film of the coil 7 is formed in the recess 13 for forming a coil. This coil 7
Has a shape wound many times so as to draw a circle with the end near the rear butting surface 11 as one end 7A. The coil 7 is drawn out into a groove 13A formed at one end of the coil forming recess 13 and the other end 7B is connected to the terminal groove 30.
Is electrically connected to the external connection terminal 15 made of a good conductor filled in the substrate.

When the coil 7 is formed, first, the above-described coil shape is patterned by a photoresist. Next, a good conductor such as Cu is formed in the coil forming recess 13 by plating or the like so as to have a thickness of about 3 μm. By removing the photoresist, the coil 7 having a patterned coil shape can be formed. In forming the coil 7, not only the plating method described above, but also
A sputtering method, an evaporation method, or the like can be used.

At this time, the coil 7 is formed under the influence of the surface property of the coil forming recess 13. According to this method, the coil-forming concave portion 13 having good surface properties can be formed, so that the coil 7 can be surely formed without any defect such as disconnection.

Next, a protective layer (not shown) for protecting the coil 7 from contact with the outside air is formed. This protective layer is formed by the coil forming recess 13 in which the above-described coil 7 is formed.
Is formed so as to be embedded. After that, a planarization process is performed on the surface on which the protective layer is formed. This flattening process is performed until the front butting surface 10, the rear butting surface 11, and the coil connection terminals 14 are exposed to the outside.

Next, as shown in FIG. 14, a substrate in which a plurality of magnetic core halves 2 and 3 are formed in parallel is provided, and one magnetic core half 2 and the other magnetic core half 3 are arranged in one row. And then joined by metal diffusion bonding so that the surfaces on which the coils 7 are formed face each other.

At the time of this metal diffusion bonding, first, a metal material made of Cr and Au is formed in a predetermined region on the surface on which the coil 7 is formed by a sputtering method or the like. In the metal diffusion bonding, after a metal film is formed in a predetermined region, a pair of substrates 21 each having a plurality of magnetic core halves 2 and 3 arranged in a row are abutted. At this time, one of the front butting surfaces 10 and the other front butting surface 10 are accurately positioned. Similarly, one of the coil connection terminals 14
And the other coil connection terminal 14 are accurately positioned. Then, by applying a predetermined temperature and pressure in the abutted state, the substrates 21 each having a plurality of magnetic core halves 2 and 3 arranged in a row can be joined to each other.
As a result, as shown in FIG. 15, a magnetic head block 32 in which a plurality of magnetic heads 1 are arranged in a line is formed.

Next, as shown in FIG. 15, the magnetic head block 32 is separated into individual magnetic heads 1. At this time, the magnetic head block 32 is cut at a portion indicated by line BB in FIG.

Thus, the magnetic head 1 having a magnetic gap between the front butting surfaces 10 is formed. Then, although not shown, the magnetic sliding surface of the magnetic head 1 is polished so that the surface has a cylindrical shape. Also,
In order to improve the contact characteristics with the magnetic recording medium, a contact restricting groove 8 is formed on the sliding surface of the medium. The contact restriction groove 8 is formed so as to be substantially parallel to the sliding direction of the magnetic recording medium, and regulates friction with the magnetic recording medium.

In the method of manufacturing a magnetic head according to the present invention as described above, the protection film 12 is formed on the recess 9 after the formation of the recess 9. In this method, the protection film 12 reliably prevents the low-melting glass 29 heated to a high temperature from contacting the surface of the concave portion 9. Therefore, according to this method, it is possible to prevent a reaction between the surface of the concave portion 9, that is, the cross section of the metal magnetic thin film 5 and the low melting point glass 29. Thus, in this method, bubbles do not exist in the low-melting glass 29 cooled and solidified.

In this case, even when the solidified glass 6 is ground to form the coil-forming recess 13, no irregularities due to bubbles are formed on the surface of the coil-forming recess 13. Therefore, according to this method, it is possible to reliably form the coil 7 having no defect such as disconnection in the coil forming recess 13. In other words, according to this method, since the coil 7 having a defect such as disconnection is not formed, the yield can be significantly improved.

More specifically, the yield when using the above-described method of manufacturing a magnetic head according to the present invention (the method of the present invention), and the method of omitting the step of forming the protective layer 12 (the conventional method). The yield when using was compared. Table 1 shows the results.

[0069]

[Table 1]

As is apparent from Table 1, when the method of manufacturing a magnetic head according to the present invention is used, almost no yield is observed due to poor conduction of the coil 7, and the yield is dramatically improved. You can see that.

[0071]

As described in detail above, since the magnetic head according to the present invention has a coil having no defect, a good current always flows through the coil and the recording / reproducing characteristics are good. ing.

In the method of manufacturing a magnetic head according to the present invention, a protective film is formed on a concave portion of a metal magnetic thin film, and thereafter,
The molten glass is filled so as to cover the metal magnetic thin film. Therefore, according to this method, no bubbles are present in the glass, and as a result, a coil-forming concave portion having good surface properties can be formed. Therefore, according to this method, it is possible to always reliably form a defect-free coil, and to improve the yield.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a magnetic head according to the present invention.

FIG. 2 is a perspective view of a main part of a medium sliding surface of the magnetic head.

FIG. 3 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view showing a substrate.

FIG. 4 is a view for explaining the method of manufacturing the magnetic head according to the present invention, and is a perspective view of the substrate on which the first groove processing has been performed.

FIG. 5 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of a substrate on which a metal magnetic thin film is formed.

FIG. 6 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of the substrate on which the second groove processing has been performed.

FIG. 7 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is an enlarged perspective view of a main part of the substrate on which the substrate having the concave portion is formed;

FIG. 8 is a view for explaining the method of manufacturing the magnetic head according to the present invention, and is an enlarged perspective view of a main part of the substrate in which a substrate having a protective film formed on a concave portion is enlarged.

FIG. 9 is a view for explaining another method for manufacturing a magnetic head according to the present invention, and is an enlarged perspective view of a main part of a substrate in which a protective film is formed on a metal magnetic thin film.

FIG. 10 is a diagram for explaining the method of manufacturing the magnetic head according to the present invention, and is a perspective view of the substrate in a state where each groove is filled with low-melting glass.

FIG. 11 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of a substrate in which terminal grooves are formed in low-melting glass.

FIG. 12 is a diagram for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of a main part of the substrate on which the coil-forming concave portion is formed.

FIG. 13 is a diagram for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of a main part of a substrate on which a coil is formed.

FIG. 14 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view showing a state in which blocks on which the magnetic core halves are formed are abutted.

FIG. 15 is a diagram for explaining the method for manufacturing the magnetic head according to the present invention, and is a perspective view of the magnetic head block.

FIG. 16 is a perspective view of a main part of a substrate when a conventional magnetic head is manufactured.

[Explanation of symbols]

Reference Signs List 1 magnetic head, 2, 3 magnetic core half, 4 non-magnetic substrate, 5 metal magnetic thin film, 6 glass, 7 coil, 8
Contact width regulating groove, 10 front butting surface, 11 rear butting surface, 12 protective film, 13 coil forming recess,

Claims (6)

[Claims] 1. A metal magnetic thin film is formed on a substrate at an angle, and a pair of magnetic core halves having a flat butted surface by filling with glass are provided. A magnetic gap is formed by abutting through the magnetic material, a coil forming recess is formed on the abutting surface of at least one magnetic core half, and a thin film coil is formed in the coil forming recess. In the head, at least one of the magnetic core halves is formed by cutting a metal magnetic thin film corresponding to the coil-forming concave portion, and a protective film is formed so as to cover at least the cut processing surface. A magnetic head characterized by being filled with glass. 2. The magnetic head according to claim 1, wherein all surfaces of the metal magnetic thin film that are in contact with the glass are covered with a protective film. 3. The magnetic head according to claim 1, wherein the protective film is a film mainly composed of an inorganic oxide. 4. A metal magnetic thin film is formed on a substrate having an inclined surface to form a pair of magnetic core halves, and a coil is formed on the metal magnetic thin film formed on at least one of the magnetic core halves. Cutting was performed corresponding to the forming recess, a protective film was formed to cover the cut surface formed on the metal magnetic thin film, and glass was filled on the substrate to flatten the butted surface, and the surface was flattened. A coil-forming recess is formed in the glass facing the butting surface, a thin-film coil is formed in the coil-forming recess, and a pair of magnetic core halves is made of a non-magnetic material so that the end faces of the metal magnetic thin film abut each other. And joined together through
A method for manufacturing a magnetic head, comprising forming a magnetic gap. 5. The method for manufacturing a magnetic head according to claim 4, wherein a protective film is formed on all surfaces of the metal magnetic thin film that are in contact with the glass. 6. The method according to claim 4, wherein the protective film is mainly made of an inorganic oxide.