JPH10269515A - Magnetic head and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely join a pair of magnetic core half bodies and to eliminate the defects in a gap length and the joining by forming non-magnetic metallic materials at both end sections at the joining surface of the bodies and constituting a magnetic head by metallic diffusion joining using the formed non-magnetic metallic material. SOLUTION: During the joining of a pair of magnetic core half bodies 2 and 3 of a magnetic head 1, gold films are formed on regions R, back section butting surfaces 11 and coil connecting terminals 13 and the bodies 2 and 3 are joined through the films. The regions R are located at the both end sections in the height direction of the head 1 and no gold film is formed in the portion sandwitched by the regions R. Thus, the head 1 is formed by joining the bodies 2 and 3 using the films mainly formed in the regions R. In other words, the portion sandwitched by the regions R is not related to the joining process.

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 pair of magnetic core halves joined by metal diffusion bonding 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-in-gap type magnetic head in which a metal magnetic film is formed on a ferrite material, which has been widely used as a conventional magnetic head for a VTR, and then wound, has a large inductance and an output per inductance. Because of the decrease, it is difficult to sufficiently cope with digital image recording that requires a high frequency and a high density because the output is low in a high frequency region.

[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.

[0005] This thin-film magnetic head includes a pair of magnetic core halves each having a metal magnetic film, and is formed by joining the pair of magnetic core halves via a non-magnetic metal material. A metal magnetic film is embedded in the magnetic core half, and a substantially rectangular coil-forming concave portion is provided at a substantially central portion thereof. Further, the magnetic core half includes a coil formed by a thin film forming technique such as photolithography in the coil forming recess.

The metal magnetic film is formed in a thin film obliquely with respect to the joining surface of the magnetic core half, and has a substantially concave shape because a coil forming recess having a coil is formed in the joining surface. That is, the metal magnetic film has a front butting surface and a rear butting surface which are divided in the front-rear direction by the coil forming recess. In this magnetic head, a magnetic gap is formed by abutting the front butting surfaces of a pair of magnetic core halves via a non-magnetic material, and the rear butting surfaces of the pair of magnetic core halves are made of a non-magnetic material. To form a back gap.

In such a thin-film magnetic head, metal diffusion bonding is used when a pair of magnetic core halves are butted and joined. In this metal diffusion bonding, for example, gold is used as the nonmagnetic metal material. By using this gold as the above-described nonmagnetic material, a magnetic gap and a back gap are formed as described above. In this metal diffusion bonding, after forming a thin film of gold on the joining surface of the pair of magnetic core halves, the pair of magnetic core halves are accurately butted, and a predetermined pressure is applied while heating to about 300 degrees. .

[0008]

By the way, in the above-described magnetic head, when a pair of magnetic core halves is joined, the joining strength is sufficient, and at the same time, the electrically connected portion and the magnetic gap are joined. There is a demand for a reliable joining of the parts that form the surface. However, in the conventional magnetic head and its manufacturing method, it cannot be said that the conditions for the metal diffusion bonding as described above have been sufficiently studied, and at present, the requirements as described above are not answered. .

More specifically, in the above-described magnetic head, since the magnetic core half is heated to about 300 ° C. during metal diffusion bonding, warpage occurs in the pair of magnetic core halves. There was something. Further, even if mirror finishing is performed after gold is formed, there may be a case where a slight step is formed on the bonding surface.

As described above, in the conventional magnetic head, the flatness of the joining surfaces of the pair of magnetic core halves cannot be said to be good. As a result, the pressure cannot be uniformly applied to the joining surface, and the pair of magnetic core halves cannot be joined reliably. That is, in the conventional magnetic head, since the surface property of the joining surface of the magnetic core halves is poor, a biased load is applied to the pair of magnetic core halves, and the entire joining surface cannot be joined. Bonding failure occurred. Such a magnetic head is not usable.

Further, in the conventional magnetic head, since a warp occurs such that a substantially central portion of the bonding surface of the pair of magnetic core halves is convex, a bonding failure may occur at a magnetic gap portion. That is, a pair of magnetic core halves
Bonding is performed at the approximate center of the convex bonding surface, and poor bonding occurs at the end where the magnetic gap is formed. In this case, the magnetic head does not have a predetermined gap length. Therefore, the magnetic head cannot be used due to a gap length defect.

In order to solve this problem, it is conceivable to apply a considerable amount of pressure to correct the flatness of the joint surface due to the warpage. However, if the pressure is too high, the magnetic core half is destroyed, which causes inconvenience.

In particular, the above-mentioned problems occur remarkably when a plurality of magnetic core halves are formed in a block shape in parallel in the gap width direction. Conventionally, manufacturing a plurality of magnetic core halves in such a block shape has
It is adopted from the viewpoint of productivity. However, in the conventional method, a large number of unusable magnetic heads are manufactured due to the above-mentioned problems, and there is a problem that the yield is low.

Accordingly, the present invention solves the above-mentioned problems of the conventional magnetic head and provides a magnetic head free from a gap length defect and a joint defect by securely joining a pair of magnetic core halves. The purpose is to do.

Further, the present invention solves the above-mentioned problems of the conventional method of manufacturing a magnetic head and provides a method of manufacturing a magnetic head with improved yield by securely joining a pair of magnetic core halves. The purpose is to provide.

[0016]

A magnetic head according to the present invention, which has achieved the above-mentioned object, comprises a pair of magnetic core halves each having a metal magnetic thin film formed obliquely on a substrate via a non-magnetic metal material. A magnetic gap is formed by metal diffusion bonding, and at least one of the magnetic core thin films of the magnetic core has a concave portion in which a coil is formed on the abutting surface with the metal magnetic thin film of the other magnetic core half. In the magnetic head, the pair of magnetic core halves forms a magnetic gap at the joint surface, and the nonmagnetic metal material is disposed at a distance from one end of the joint surface to the other end of the joint surface. Is what is done.

In the magnetic head according to the present invention configured as described above, a non-magnetic metal material is formed on both ends of the joining surface of the pair of magnetic core halves. Then, the pair of magnetic core halves are metal diffusion bonded by a non-magnetic metal material formed at both ends of the bonding surface to form a magnetic head.

At this time, the pair of magnetic core halves are joined mainly at both ends separated from each other. For this reason, in the pair of magnetic core halves, the substantially central portion of the joining surface does not contribute to the joining. Therefore, in a pair of magnetic core halves,
Even if warpage occurs, there is little effect on metal diffusion bonding. In other words, even if the pair of magnetic core halves are warped and the heights at the substantially central portion and both ends of the joining surface are different, the height at both ends is substantially the same, so Joined to.

Further, in the magnetic head according to the present invention, the non-magnetic metal material has a thickness of 25% with respect to the area of the joining surface of the magnetic core half.
It is preferably such that it is formed at a rate of up to 35%.

In this case, in the magnetic head according to the present invention, the pair of magnetic core halves can be joined with good joining strength, and a joining defect caused by warpage or the like can be avoided.

On the other hand, in the method of manufacturing a magnetic head according to the present invention which has solved the above-mentioned problems, a metal magnetic thin film is formed obliquely on a substrate to form a pair of magnetic core halves, and at least one of the magnetic core halves is formed. For the metal magnetic thin film formed on the core half, a recess is formed on the abutting surface with the other metal magnetic thin film,
A method of manufacturing a magnetic head in which a coil is formed in the concave portion by a thin film forming step, and the pair of magnetic core halves are metal-diffused and bonded via a non-magnetic metal material to form a magnetic gap. The non-magnetic metal material is formed at one end forming the magnetic gap of the joining surface of the core halves and the other end of the joining surface to form the non-magnetic metal material. Are joined so as to face each other and are bonded by metal diffusion.

According to the method of manufacturing a magnetic head according to the present invention having the above-described configuration, a non-magnetic metal material is formed at both ends of the magnetic core half apart from each other, and the non-magnetic metal material is formed via the non-magnetic metal material. A pair of magnetic core halves are metal diffusion bonded. That is, in this method, the substantially central portion of the joining surface between the pair of magnetic heads is not used for metal diffusion joining. For this reason, according to this method, even when the warp or the like occurs in the pair of magnetic heads and the heights of the substantially central portion and both end portions of the bonding surface are different, the pair of magnetic core halves are securely bonded. can do.

In the method of manufacturing a magnetic head according to the present invention, it is preferable that the non-magnetic metal material is formed in a ratio of 25 to 35% with respect to the area of the bonding surface of the magnetic core half.

In this case, according to the method of manufacturing a magnetic head of the present invention, a pair of magnetic core halves can be joined with sufficient joining strength, and joint failure due to warpage or the like can occur. Absent.

Further, in the method of manufacturing a magnetic head according to the present invention, it is preferable that the pair of magnetic core halves on which the non-magnetic metal material is formed be subjected to metal diffusion bonding at a pressure of 10 to 20 MPa.

In this case, according to the method of manufacturing a magnetic head according to the present invention, since a pressure is applied in this range, a joining failure does not occur when joining a pair of magnetic core halves.
In addition, bonding can be reliably performed without breaking the substrate or the like.

[0027]

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
And a metal magnetic film 6 formed obliquely on the non-magnetic substrate 4. Further, at least one of the pair of magnetic core halves 2 and 3 is formed with a coil 7 for excitation or detection of an induced electromotive voltage. In the magnetic head 1, the metal magnetic film 6 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. 1 in a state where the magnetic core halves 2 and 3 are joined. A signal magnetic field is recorded on a magnetic recording medium.

The magnetic head 1 is provided with a contact width regulating groove 8 for adjusting the 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. Further, in this magnetic head, the sliding surface of the magnetic recording medium has an arc shape in order to adjust the contact state with the magnetic recording medium.

In this magnetic head 1, the metal magnetic film 6
Are 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 film 6 is configured such that its cross-sectional shape is substantially U-shaped. That is, the metal magnetic film 6
Is formed such that a substantially central portion of an end surface on the side of the surface where the magnetic core halves 2 and 3 are joined is a concave portion.

For this reason, the metal magnetic film 6 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 in the front-rear direction. 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. . Also, this magnetic head 1
Then, similarly, the rear butting surface 1 of one magnetic core half 2
1 and the rear butting surface 11 of the other magnetic core half 3 are butted via a gap material G to form a back gap.

In the magnetic head 1, the metal magnetic film 6 has three metal magnetic layers 6B via the nonmagnetic layer 6A.
Are stacked. 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 according to the present invention may have, for example, a single-layer metal magnetic thin film, or may have tens of metal magnetic thin films.

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 film 6 is made of, for example, Fe-A
It is made of a metallic magnetic material such as an l-Si alloy (Sendust), but is not limited thereto. Fe-Al alloy, Fe-Si-
Co alloy, Fe-Ga-Si alloy, Fe-Ga-Si-
What is necessary is just to consist of crystalline alloys, such as Ru alloy, Fe-Al-Ge alloy, Fe-Ga-Ge alloy, Fe-Si-Ge alloy, Fe-Co-Si-Al alloy, and Fe-Ni alloy. Alternatively, the metal magnetic film 6 is made of Fe, Co, Ni.
Consisting of at least one of the above elements and one or more of the elements P, C, B and Si,
1, Ge, Be, Sn, In, Mo, W, Ti, Mn,
Metal-metalloid amorphous alloys typified by alloys containing 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 f or Zr and a rare earth element as main components.

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 12 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 12. The coil 7 has one end 7A on the center side thereof connected to the coil connection terminal 13. Then, the coil 7 has a rear abutting surface 11 with the coil connection terminal 13 as a base end.
Is formed so as to draw a circle around the center.

The coil connection terminals 13 formed on the pair of magnetic core halves 2 and 3 are formed in the coil forming recesses 12, and are substantially the center of the coil 7, and are formed on the rear butting surface 11. It is formed in the vicinity. The coil connection terminal 13 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 this magnetic head 1, when the pair of magnetic core halves 2 and 3 are joined, the pair of coil connection terminals 13 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 a gold film is formed on the bonding surface 2A, 3A on the region R indicated by the broken line in FIG. 1, the rear abutting surface 11, and the coil connection terminal 13, respectively. 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 14. The external connection terminal 14 is configured by burying a conductive material such as copper in a terminal groove 15 formed in the width direction of the pair of magnetic core halves 2 and 3 with a predetermined depth. . The external connection terminals 14 can be electrically connected to the outside and the coil 7 by being exposed on the side surface of the magnetic head 1. The pair of external connection terminals are formed at positions where the heights of the pair of magnetic core halves 2 and 3 are different so that a short circuit does not occur when the pair of magnetic core halves 2 and 3 are joined. I have.

In the magnetic head 1 according to the present embodiment configured as described above, when the pair of magnetic core halves 2 and 3 are joined, the region R, the rear butting surface 11 and the coil connection terminal 13 are formed. It has a coated gold film. For this reason, the pair of magnetic core halves 2 and 3 are joined via these gold films. Here, the regions R are located at both ends in the height direction of the magnetic head 1. In the magnetic head 1, a gold film is not formed in a portion sandwiched between the regions R.

Therefore, the magnetic head 1 is formed by joining the pair of magnetic core halves 2 and 3 mainly by the gold film formed in the region R. That is,
In this magnetic head, the portion sandwiched by the regions R does not participate in the joining.

Therefore, for example, when the pair of magnetic core halves 2 and 3 warp with respect to each other so that the substantially central portion of each joint surface is convex, that is, the portion sandwiched by the region R is a region. Even if it is convex compared to R, the convex portion sandwiched between the regions R does not hinder the bonding.

Therefore, in the magnetic head 1, the front butting surfaces 10 facing each other are securely joined. Therefore, the magnetic head 1 has a desired magnetic gap without inconvenience such as a gap length defect.

Further, in the magnetic head 1, the pair of magnetic core halves 2, which are securely joined by the gold film formed in the region R irrespective of the surface properties of the portion sandwiched between the regions R,
3 will be provided. For this reason, in the magnetic head 1, there is no occurrence of a bonding defect due to the surface properties of the bonding surfaces 2A and 3A.

In the magnetic head 1 described above, the gold film is
It is preferably formed at a rate of 25 to 35% with respect to the area of the joining surfaces 2A and 3A. By forming the gold film in this range, the pair of magnetic core halves 2 and 3 can be bonded with high bonding strength, and the bonding failure due to the above-described warpage or the like can be more reliably prevented. Can be reduced.

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 substrate plane, but more preferably about 35 to 50 ° in consideration of the pseudo gap and track width accuracy. . 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 film 6 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 film 6 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 film 6 is formed such that three layers of metal magnetic materials are laminated via a nonmagnetic layer. This film forming step is performed, for example, by a PVD method such as a magnetron sputtering method or a CV method.
This is performed by the D method or the like.

Further, the metal magnetic film 6 is not limited to the one having a plurality of metal magnetic layers, but may have a configuration of a single metal magnetic layer.

In the present embodiment, the metal magnetic film 6 is
In the case of a multi-layer structure, for example, Fe-Al-Si
0.15 μm of alumina was alternately laminated on 5 μm of the alloy (Sendust) to form a structure having three Fe—Al—Si alloy layers. When the metal magnetic film 6 is composed of a plurality of layers, materials such as alumina, SiO _2, and SiO are used alone or as a mixture for the non-magnetic layer. The thickness of the non-magnetic layer needs to be large enough to allow insulation between adjacent metal magnetic layers.

Next, as shown in FIG. 6, a second groove is formed on the surface on which the metal magnetic film 6 is formed in a direction substantially perpendicular to the magnetic core forming groove 24. In the second groove processing, a separation groove 26 formed to separate the magnetic core into a desired size, and a winding for forming a coil forming recess in each magnetic core separated by the separation groove 26. A line groove 27 is 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, it is necessary to provide as many as 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 film 6 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 26
The depth dimension is 150 μm deeper than the bottom of the magnetic core forming groove 24, that is, 280 μm.

On the other hand, the winding groove 27 forms a magnetic core having the front butting surface 10 and the rear butting surface 11, and is formed so as not to cut the metal magnetic film 6 to form the coil forming recess 12. It must be formed with a depth dimension. The shape of the winding groove 27 is determined according to the length of the front butting surface 10 and the back gap 11. Here, the width is about 140 μm, and the length of the front butting surface 10 is about 140 μm. The dimensions are about 300 μm, and the length dimension of the rear butting surface 11 is about 85 μm. The winding groove 27 may have such a depth that the metal magnetic film 6 is not cut. However, if the winding groove 27 is too deep, the magnetic path length may be increased and the efficiency of magnetic flux transmission may be reduced. In addition, winding groove 2
The depth of the coil 7 depends on the thickness of the coil 7 formed in a step described later, but is, for example, about 20 μm.
m. Further, the shape of the winding groove 27 is not limited, but here, for example, the side surface on the front abutting surface 9 side is an inclined surface 27A of about 45 °. As a result, the metal magnetic film 6 has a structure in which the magnetic flux is concentrated on the front butting surface 9 side, thereby improving the sensitivity.

Next, as shown in FIG. 7, the low-melting glass 29 melted on one main surface of the substrate 21 on which the magnetic core forming groove 24, the separation groove 26, and the winding groove 27 are formed as described above. Is filled. Then, a surface flattening process is performed on one main surface filled with the low-melting glass 29.

Next, as shown in FIG. 8, 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. And this terminal groove 3
0 is filled with a good conductor such as Cu 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 serves as the external connection terminal 14 in the magnetic head 1 described above.

Next, as shown in FIG. 9, a coil forming recess 12 in which the coil 7 is formed as a thin film is formed. The coil forming concave portion 12 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. The coil forming recess 12 has a groove 12 extending from one end to the terminal groove 30.
A.

Next, as shown in FIG. 10, the coil 7 is formed in a thin film in the coil forming recess 12. 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 pulled out into a groove 12A formed at one end of the coil forming recess 12, and the other end 7B is connected to the terminal groove 30.
Is electrically connected to the external connection terminal 14 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 12 by plating or the like so as to have a thickness of about 3 μm. Then, 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.

Next, as shown in FIG. 11, a coil connection terminal 13 is formed at one end 7A of the coil 7. The coil connection terminal 13 is formed on one end 7 </ b> A of the coil 7 near the rear butting surface 11. The coil connection terminal 13 is made of a good conductor material and has a height dimension substantially equal to the joining surfaces 2A and 3A of the pair of magnetic core halves 2 and 3.

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 12 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 terminal 13 are exposed to the outside.

Next, as shown in FIG. 12, a substrate in which a plurality of magnetic core halves 2 and 3 are formed in parallel is used. 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.

In this metal diffusion bonding, first, as shown in FIG. 13, a gold film 31 made of gold, which is a nonmagnetic metal material, is formed. The gold film 31 is formed only in the region R surrounded by the broken line in FIG. 13, the rear butting surface 11, and the coil connection terminal 13. That is, in order to join the pair of magnetic core halves 2 and 3, the gold film 31 and the region R formed around the coil forming concave portion 12 including the front butting surface 10 and the opposite side of the front butting surface 10. It is formed on the rear butting surface 11.
The gold film 31 is formed on the coil connection terminal 13 in order to obtain electrical conduction between the pair of coils 7 formed on the pair of magnetic core halves 2 and 3 respectively.

In this metal diffusion bonding, the gold film 3
1 is preferably formed so as to be 25 to 35% of the area of the joint surfaces 2A and 3A.

In order to form the gold film 31 in the predetermined area as described above, first, the surface on which the coil 7 is formed
A metal material made of Cr and Au is formed by a sputtering method or the like. Next, a mask is patterned on the gold film 31 by a photo process. This mask is
It is formed in a portion corresponding to the above-mentioned predetermined area. Then, by removing the gold film 31 other than the region where the mask is formed, the gold film 31 can be formed only in the above-described region.

In the metal diffusion bonding, a gold film 31
Is formed, as shown in FIG. 14, a pair of substrates 21 in each of which a plurality of magnetic core halves 2 and 3 are 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 coil connection terminal 13 and the other coil connection terminal 13 are accurately positioned. Then, a predetermined temperature and pressure are applied in a state where the magnetic core halves 2 and 3 are arranged in a row.
1 can be joined together. Thus, a magnetic head block 32 in which a plurality of magnetic heads 1 are arranged in a line is formed.

At this time, the pair of magnetic core halves are
5, a jig 40 is used to apply pressure. The jig 40 includes a base 42 having an abutment wall 41.
And a fixed block 43 abutted and fixed to the abutting wall 41, and a movable block 44 that moves toward and away from the fixed block 43.

When metal diffusion bonding is performed using this jig 40, the fixed block 4 is held in a state where a pair of substrates 21 each having a plurality of magnetic core halves 2, 3 arranged in a row abut each other.
3 and the movable block 44. Then, the movable block 44 is moved in the direction indicated by the arrow in FIG. As a result, a predetermined pressure is applied, and the magnetic head block 32 is formed.

At this time, when the magnetic head block 32 is formed, a pressure of 10 to 20 MPa is applied to a pair of substrates 21 each having a plurality of magnetic core halves 2 and 3 arranged in a line. Preferably, it is added. When the magnetic head block 32 corresponds to 40 magnetic heads 1, the area of the gold film 31 is 6 to 12 kg with respect to the magnetic head block 32.
f will be weighted.

At this time, the pair of front butting surfaces 10 are joined via a gold film 31 made of Cr and Au, which are nonmagnetic good conductors. For this reason, a pair of front butting surfaces 10
The gap between them is a magnetic gap in the magnetic head 1. On the other hand, the pair of rear butting surfaces 11 are similarly joined via the gold film 31 made of Cr and Au, and thus constitute a back gap.

The pair of coil connection terminals 13 are joined via a gold film 31 made of Cr and Au, which are nonmagnetic good conductors. Therefore, the pair of coil connection terminals 13 is electrically connected. As a result, the coil 7 disposed opposite to the coil connection terminal 1
3 are electrically connected.

Next, 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 gold film 31 is formed on the region R, the rear butting surface 11 and the coil connection terminal 13 during metal diffusion bonding. On the other hand, in the conventional method, as shown in FIGS.
Is formed, and the pair of magnetic core halves 53 and 54 are joined.

In the method according to the present invention and the conventional method, warping may occur in the pair of magnetic core halves 2, 3, 53, 54 as shown by arrows in FIGS. is there. In this case, in the conventional method, the portions of the gold film 52 formed at the substantially central portions of the pair of magnetic core halves 53 and 54 are subjected to metal diffusion bonding. It is difficult to join. Therefore,
In the conventional method, the gap length may not be a desired value, and a gap length defect may occur.

On the other hand, in the method according to the present invention, as shown in FIG. 18, when bonding the pair of magnetic core halves 2 and 3, the gold film 31 is placed near both ends of the bonding surfaces 2A and 3A. Since only the bonding surfaces are formed, the vicinity of substantially the center of the bonding surfaces 2A and 3A is not involved in metal diffusion bonding. Therefore, according to this method, the joining surfaces 2A and 3A of the pair of magnetic core halves 2 and 3 are used.
The magnetic head can be manufactured without causing defective bonding even if the surface property of the magnetic core is poor or the pair of magnetic core halves 2 and 3 are warped.

In the method of manufacturing a magnetic head according to the present invention, as described above, the gold film 31 is formed only in a relatively narrow area. For this reason, even if the pressure applied when forming the magnetic head block 32 is the same as that of the related art, the pressure applied per unit area increases in the method according to the present invention. In other words, in the method according to the present invention, even if a smaller pressure is applied to the magnetic head block 32 than before, the pressure applied per unit area can be increased.

As described above, according to the method of the present invention,
The pressure applied per unit area can be increased.
Therefore, according to the method of the present invention, metal diffusion bonding can be performed more stably. Therefore, according to this method, the pair of magnetic core halves 2 and 3 can be reliably joined with a strong joining strength.

Further, in the method according to the present invention, as described above, the pressure applied to the magnetic head block 32 can be made smaller than that in the related art. Therefore, according to the method according to the present invention, the magnetic head block 3
When applying pressure to 2, the load on the jig 40 can be reduced. Further, as described above, in this method, since a relatively small pressure is applied to the magnetic head block 32, the possibility of damaging the low melting point glass, the substrate, and the like is reduced. Further, since the pressure applied to the magnetic head block 32 is small, the stress applied to the metal magnetic film 6 is also reduced as compared with the related art, and deterioration of the magnetic characteristics of the magnetic core can be suppressed.

Specifically, in the method according to the present invention, as described above, when a pressure of 10 to 20 MPa is applied to the gold film 31, reliable metal diffusion bonding can be performed. As described above, when forming the magnetic head block 32 corresponding to 40 magnetic heads, a pressure of 6 to 12 kgf is applied to the magnetic head block 32. That is, in the method according to the present invention, the gold film 3
Since 1 is formed in a relatively narrow area, 6 to 12 k
By applying a pressure of gf to the magnetic head block 32, a pressure of 10 to 20 MPa can be applied. On the other hand, when the gold film 31 is formed on substantially the entire surfaces of the bonding surfaces 2A and 3A, the pressure is 10 to 20 MPa.
, It is necessary to apply a pressure of 20 kgf or more to the magnetic head block 32. When a pressure of 20 kgf or more is applied to the magnetic head block 32, as described above, the low melting point glass, the substrate, and the like may be damaged, or the magnetic characteristics of the magnetic core may be deteriorated.

In the magnetic head and the method of manufacturing the same according to the present invention, it is preferable that the gold film 31 is formed at a rate of 25 to 35% with respect to each area of the bonding surfaces 2A and 3A. In order to verify this, the following experiment was performed.

In the magnetic head 1 described above, the gold film 31
Was changed variously, and the occurrence rate of defects at that time was measured. However, in this magnetic head, the area of the portion formed near the front abutting surface 10 in the region R is equal to the bonding surface 2.
A is about 12% of each area of A and 3A. The gold film 31 in this portion cannot be reduced to form a magnetic gap. For this reason, in order to change the ratio of the gold film 31, the area of the gold film 31 in the portion of the region R opposite to the front butting surface 10 was changed.

Then, the magnetic head 1 was manufactured by changing the area of the gold film 31 in various ways, and the occurrence of defects due to the warpage of the pair of magnetic core halves 2 and 3 at that time was measured.
The results are shown in graph a in 9. Similarly, the magnetic head 1 was manufactured, and the defect occurrence rate due to the increase in the area of the gold film 31 was measured. The result is shown by a graph b in FIG. Note that the graph b shows the defect occurrence rate when all the formed gold films 31 are bonded.

In FIG. 19, the ratio of the area of the gold film 31 to the bonding surfaces 2A and 3A is shown by a graph c.

As is apparent from FIG. 19, the gold film 31
When the area is 25 to 35% of the area of each of the joining surfaces 2A and 3A, the pair of magnetic core halves 2 and 3
Can be joined more reliably.

[0086]

As described in detail above, in the magnetic head according to the present invention, since the pair of magnetic core halves are securely joined by the non-magnetic insulating material, defective joining and defective gap length and the like occur. Does not occur. Therefore, this magnetic head has high reliability because of its high bonding strength.

In the method of manufacturing a magnetic head according to the present invention, a pair of magnetic core halves can be securely bonded at the time of metal diffusion bonding. Therefore, according to this method, it is possible to suppress the occurrence of a failure due to a bonding failure or the like, and to manufacture a magnetic head with a high 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 diagram for explaining the method for manufacturing a magnetic head according to the present invention, and is a perspective view of a substrate on which a metal magnetic 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 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. 8 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. 9 is a view for explaining the method of 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 recess is formed.

FIG. 10 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. 11 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 coil connection terminals are formed.

FIG. 12 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 where blocks on which the magnetic core halves are formed are butted.

FIG. 13 is a view for explaining the method for manufacturing the magnetic head according to the present invention, and is a plan view of a main part showing a gold film formed at the time of metal diffusion bonding.

FIG. 14 is a view 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. 15 is a perspective view of a jig for performing metal diffusion bonding in the present invention.

FIG. 16 is a plan view of a main part showing a gold film of a conventional magnetic head.

FIG. 17 is a cross-sectional view of relevant parts when a pair of magnetic heads in a conventional magnetic head is joined.

FIG. 18 is a fragmentary cross-sectional view of the magnetic head according to the present invention when a pair of magnetic heads is joined.

FIG. 19 is a characteristic diagram showing a preferable range of the area of the gold film in the magnetic head according to the present invention.

[Explanation of symbols]

1 magnetic head, 2, 3 magnetic core half, 4 non-magnetic substrate, 6 metal magnetic film, 7 coil, 8 width control groove,
10 front butting surface, 11 rear butting surface, 12 concave portion for coil formation, 13 terminal for coil connection, 31 gold film

Claims (7)

[Claims] A pair of magnetic core halves each formed by obliquely forming a metal magnetic thin film on a substrate are metal-diffusion bonded via a non-magnetic metal material to form a magnetic gap, and at least one of the magnetic core halves is formed. A magnetic metal thin film of a body, a concave portion in which a coil is formed in a thin film is formed on an abutting surface with the metal magnetic thin film of the other half of the magnetic core; A magnetic head characterized in that the nonmagnetic metal material is formed at one end of the magnetic gap and the other end of the joining surface so as to be separated from each other, and is subjected to metal diffusion bonding. 2. The magnetic head according to claim 1, wherein the non-magnetic metal material is gold. 3. The magnetic head according to claim 1, wherein the non-magnetic metal material is formed in a ratio of 25 to 35% with respect to an area of a joining surface of the magnetic core half. 4. A metal magnetic thin film is formed obliquely on a substrate to form a pair of magnetic core halves, and the metal magnetic thin film formed on at least one of the magnetic core halves is replaced with the other metal core. A concave portion is formed in the abutting surface with the magnetic thin film, a coil is formed in the concave portion by a thin film forming process, and the pair of magnetic core halves are subjected to metal diffusion bonding through a non-magnetic metal material to form a magnetic gap. In the method for manufacturing a head, the nonmagnetic metal material is formed at a distance from one end of the joining surface of the pair of magnetic core halves forming a magnetic gap and the other end of the joining surface, A method of manufacturing a magnetic head, comprising: butting a half of a core such that the non-magnetic metal material faces each other and performing metal diffusion bonding. 5. The method according to claim 4, wherein the nonmagnetic metal material is gold. 6. The method of manufacturing a magnetic head according to claim 4, wherein said non-magnetic metal material is formed in a ratio of 25 to 35% with respect to an area of a joining surface of said magnetic core half. 7. The method of manufacturing a magnetic head according to claim 4, wherein said pair of magnetic core halves on which said nonmagnetic metal material is formed are metal diffusion bonded at a pressure of 10 to 20 MPa.