JP2000090410A - Magnetic head and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve corrosion resistance by butting the magnetic metallic thin films diagonally deposited on substrates against each other in such a manner that the front part butt surfaces thereof face to each other via nonmagnetic materials to form a magnetic gap and exposing the magnetic metallic thin films outward only at the sliding surfaces on which a magnetic recording medium slide. SOLUTION: The magnetic metallic thin films 4 are formed on the slopes 3a diagonally formed at a prescribed angle on the nonmagnetic substrates 3. When a pair of magnetic core half bodies 2 are joined via the nonmagnetic films 7, the magnetic core 8 is disposed diagonally with the sliding direction and the front part butt surfaces 12 are butted against each other, by which the front gap is constituted. Thin-film coils 6 are formed within a coil forming recessed part 16 approximately around the rear part butt surfaces 13. The end on the central side of the thin-film coils 6 is connected to a coil connecting terminal 17 and the end on the outer peripheral side is connected to an external connecting terminal 18. The magnetic metallic thin films 4 are exposed outward only at the sliding surfaces 9 but are not exposed outward at both flanks 1a of the magnetic head and contact width regulating grooves 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a magnetic head 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 A magnetic head is mounted on a magnetic recording / reproducing device such as a video tape recorder (VTR), and records and / or reproduces information signals on a magnetic recording medium (hereinafter referred to as recording / reproducing). Is what you do.

In a magnetic head, a metal magnetic thin film is formed on each magnetic gap forming surface of a pair of magnetic core halves made of single crystal ferrite or the like, and the pair of magnetic core halves are joined to the magnetic gap forming surfaces. A so-called metal-in-gap (MIG) type magnetic head, which is integrated by bonding together, and a so-called laminated type magnetic head in which a metal magnetic thin film is sandwiched between nonmagnetic ceramic substrates have been proposed and put into practical use.

[0004] In order to cope with higher density and digitization of a recording signal in the field of magnetic recording, a magnetic head that can exhibit good electromagnetic conversion characteristics in a higher frequency band is desired. Further, it is desired that a magnetic head for a VTR be miniaturized in order to cope with miniaturization and high performance of the apparatus by mounting a plurality of magnetic heads on a small drum.

The above-described MIG type magnetic head has a large impedance and is not suitable for use in a high frequency band. Also,
The stacked magnetic head requires a reduction in the thickness of the metal magnetic thin film forming the magnetic path with a decrease in the track width due to an increase in the density of the recording signal. There is a limit to miniaturization.

Therefore, as a magnetic head capable of exhibiting good electromagnetic conversion characteristics in a high frequency band, for example, as described in JP-A-6-259717, "Magnetic head and its manufacturing method". A so-called bulk thin-film magnetic head has been proposed in which the impedance is reduced by shortening the magnetic path of a magnetic core manufactured by a thin-film forming process.

In this bulk thin film type magnetic head, a pair of magnetic core halves each having a metal magnetic thin film formed as a magnetic core on a nonmagnetic substrate are joined and integrated with each other via the nonmagnetic film. A magnetic gap is formed between these metal magnetic thin films. In this bulk thin-film magnetic head, a coil-forming recess is formed on a joining surface of at least one of the pair of magnetic core halves, and a thin-film coil is formed in the coil-forming recess. .

[0008]

By the way, a magnetic recording medium is required to have a high coercive force in order to cope with a higher density of a recording signal. Therefore, in the magnetic head, a soft magnetic film having a high saturation magnetic flux density is used for recording and reproducing a recording signal on a magnetic recording medium having a high coercive force in response to a high density of the recording signal. It is necessary to use it.

In the above-mentioned bulk thin film magnetic head, it is preferable to use an Fe-based soft magnetic alloy such as sendust for the magnetic core. However, in the case of using a Fe-based soft magnetic alloy or the like for the magnetic core of the bulk thin film magnetic head, in order to increase the saturation magnetic flux density in accordance with the higher density of the recording signal as described above, F at
It is necessary to increase the content of e and the like.

However, in a magnetic head using an Fe-based soft magnetic alloy film such as a bulk thin-film type magnetic head, if the content of Fe or the like in the magnetic core is increased, the corrosion resistance is deteriorated, and quality defects due to rust and the like are increased. There was a risk that it would be lost.

Accordingly, the present invention increases the saturation magnetic flux density of the magnetic core by exposing the metal magnetic thin film forming the magnetic core only on the sliding surface on which the magnetic recording medium slides, An object of the present invention is to provide a magnetic head with improved corrosion resistance.

Further, according to the present invention, when notching an end of a metal magnetic thin film forming a magnetic core on a sliding surface side on which a magnetic recording medium slides, the positioning is performed relative to the winding groove. By this, the variation of the electromagnetic conversion characteristics in the magnetic head where the metal magnetic thin film is exposed only on the sliding surface is suppressed,
An object of the present invention is to provide a method for manufacturing a magnetic head with improved production efficiency.

[0013]

In order to achieve the above-mentioned object, a magnetic head according to the present invention comprises a metal magnetic thin film formed obliquely on a substrate and a concave portion formed with a thin-film coil. The magnetic gap includes a pair of magnetic core halves each having a flat butted surface made of a non-magnetic material, and a magnetic gap formed by abutting the front butted surfaces of the metal magnetic thin film so as to face each other via the non-magnetic material. In the formed magnetic head, the metal magnetic thin film is exposed outward only on the sliding surface on which the magnetic recording medium slides.

In the magnetic head according to the present invention configured as described above, since the metal magnetic thin film is exposed only on the sliding surface, the content of Fe and the like in the metal magnetic thin film is increased to increase the saturation magnetic flux. Even when the density is increased, the corrosion resistance can be improved.

In order to achieve the above object, a method of manufacturing a magnetic head according to the present invention comprises forming a metal magnetic thin film obliquely on a substrate and forming a winding groove in which a thin film coil is formed. A magnetic head for forming a magnetic gap by butting a pair of magnetic core halves having flat butted surfaces with a non-magnetic material so that the front butted surfaces of the metal magnetic thin film face each other with a non-magnetic material interposed therebetween; Forming the winding groove, and sliding the magnetic recording medium of the metal magnetic thin film with respect to the top of the winding groove on the side of the front abutting surface. The metal magnetic thin film is formed so as to be exposed only on the sliding surface by passing through a removing step of notching the end on the moving surface side.

Therefore, according to the method of manufacturing a magnetic head according to the present invention, the processing accuracy can be improved when notching the end of the metal magnetic thin film on the sliding surface side. for that reason,
According to such a method of manufacturing a magnetic head, it is possible to suppress variations in the electromagnetic conversion characteristics of the magnetic head and improve production efficiency.

Further, in order to achieve the above-mentioned object,
A method of manufacturing a magnetic head according to the present invention includes a pair of a metal magnetic thin film formed obliquely on a substrate, a winding groove in which a thin film coil is formed, and a mating surface made flat by a nonmagnetic material. In a method of manufacturing a magnetic head in which a magnetic core half is butted so that front butting surfaces of the metal magnetic thin film face each other via a non-magnetic material to form a magnetic gap, the magnetic recording medium of the metal magnetic thin film may be A removing step of notching an end on the sliding surface side to slide, and a winding groove forming step of forming the winding groove with the notch of the metal magnetic thin film formed in the removing step as a position reference. Through this process, the metal magnetic thin film is formed so as to be exposed only on the sliding surface to the outside.

Therefore, according to the method of manufacturing a magnetic head according to the present invention, processing accuracy can be improved when forming a winding groove for determining the gap depth of the magnetic head. Therefore, according to the method for manufacturing a magnetic head, the defect rate of the magnetic head can be suppressed, and the production efficiency can be improved.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. Hereinafter, the magnetic head 1 as shown in FIGS. 1 and 2 will be described.

The magnetic head 1 according to the present invention comprises a pair of magnetic core halves 2 joined by metal diffusion bonding. The pair of magnetic core halves 2 includes a non-magnetic substrate 3 made of a MnO—NiO-based non-magnetic material,
And a low melting point glass 5 formed on the non-magnetic substrate 3 so as to cover the metal magnetic thin film 4. Also,
At least one of the pair of magnetic core halves 2 is formed with a thin-film coil 6 for excitation and / or detection of an induced electromotive voltage.

In the magnetic head 1, in a state where the pair of magnetic core halves 2 are joined via the non-magnetic film 7, the metal magnetic thin film 4 is connected to the thin film coil 6 in FIG. (Not shown)), a magnetic core 8 is formed. When the magnetic recording medium slides in the direction indicated by arrow A in FIG. 2, the magnetic core 8 reproduces the signal magnetic field recorded on the magnetic recording medium, or the magnetic core 8 generates the signal magnetic field. It operates by recording on a recording medium.

In order to adjust the contact state of the magnetic head 1 with the magnetic recording medium, the sliding surface 9 of the magnetic recording medium is moved in the same direction as the sliding direction of the magnetic recording medium indicated by the arrow A in FIG. It is formed in an arc shape in parallel. In addition, the magnetic head 1 is provided with a contact width regulating groove 10 for adjusting the contact area with the magnetic recording medium. The contact width regulating grooves 10 are formed on both side surfaces 1 a of the magnetic head 1 in parallel with the sliding direction A of the magnetic recording medium.

In the magnetic head 1, the metal magnetic thin film 4 is formed of a soft magnetic material such as sendust (Fe-Al-Si alloy). The metal magnetic thin film 4 is formed on an inclined surface 3 a formed obliquely at a predetermined angle on the non-magnetic substrate 3. Therefore, when the pair of magnetic core halves 2 on which the metal magnetic thin film 4 is formed are joined via the non-magnetic film 7, the magnetic core 8 slides in the sliding direction of the magnetic recording medium as shown in FIG. A is arranged obliquely with respect to A.

The metal magnetic thin film 4 is configured so that its cross section has a substantially U-shape. That is, the metal magnetic thin film 4 has a concave portion 4a at a substantially central portion of the end surface on the joint surface 2a side of the pair of magnetic core halves 2.

For this reason, the metal magnetic thin film 4 has a front butting surface 12 and a rear butting surface 13 which are divided in the front-rear direction by the joining surfaces 2 a of the pair of magnetic core halves 2 and are exposed from the low melting point glass 5. Will have. The front butting surface 12 of one magnetic core half 2 and the front butting surface 12 of the other magnetic core half 3 are butted with the nonmagnetic film 8 interposed therebetween to form a front gap 14. Also, the rear butting surface 13 of one magnetic core half 2 and the rear butting surface 13 of the other magnetic core half 3 are butted via the nonmagnetic film 8 to form a back gap 15.

The metal magnetic thin film 4 has a bonding surface 2a
And a coil forming recess 16 in which the thin-film coil 6 having the rear butting surface 13 substantially at the center is formed. A coil connection terminal 17 is formed in the coil forming recess 16 near the rear butting surface 13. Thin film coil 6
Is formed in the coil forming recess 16, and the end on the center side is connected to the coil connecting terminal 17.

The coil connection terminals 17 are formed with their heights adjusted so as to form the same surface as the joint surface 2a of the pair of magnetic core halves 2. And the magnetic head 1
In this case, when the pair of magnetic core halves 2 are joined, the pair of coil connection terminals 17 are also joined. Thus, in the magnetic head 1, when the pair of magnetic core halves 2 are joined, the pair of thin-film coils 6 are electrically connected.

The outer peripheral end of the thin film coil 6 is led out to the side opposite to the sliding surface 9 of the recording medium. External connection terminals 18 are formed on the pair of magnetic core halves 2 on the side opposite to the sliding surface 9 of the recording medium. The outer peripheral end of the thin-film coil 6 is connected to the external connection terminal 18.

By exposing these external connection terminals 18 to the side surface 1 a of the magnetic head 1, the outside and the thin film coil 6 can be electrically connected. The pair of external connection terminals 18 are formed at different positions on the pair of magnetic core halves 2 so as not to cause a short circuit when the pair of magnetic core halves 2 are joined.

The metal magnetic thin film 4 forming the magnetic core 8 is exposed only on the sliding surface 9 as shown in FIG. That is, the magnetic core 8 is not exposed outward on both side surfaces 1 a of the magnetic head 1 and the end surface 10 a of the contact width regulating groove 10.

Thus, in the magnetic head 1, the metal magnetic thin film 4 can be kept from contacting the outside air to a minimum. Therefore, the magnetic head 1 can prevent the metal magnetic thin film 4 from being oxidized. Therefore, when the content of Fe or the like contained in the metal magnetic thin film 4 is increased, the metal magnetic thin film 4 is prevented from being oxidized. It is possible to prevent the electromagnetic conversion characteristics from deteriorating due to rust and the like.

Therefore, the magnetic head 1 increases the saturation magnetic flux density of the magnetic core 8 by increasing the content of Fe and the like contained in the metal magnetic thin film 4 to increase the coercive force corresponding to the high density of the recording signal. A recording signal can be recorded and reproduced even on a high magnetic recording medium.

As shown in FIG. 2, the magnetic core 8 has a pair of notches 8a on both sides of the sliding surface 9 so as to be exposed only on the sliding surface 9. As shown in FIG. Is desirable. In such a case, the magnetic core 8 is formed by, for example, notching the metal magnetic thin film 4 formed on the inclined surface 3 a of the nonmagnetic substrate 3 at a portion corresponding to a portion removed by the hit width regulating groove 10. The notch 8a is formed.

In the present embodiment, the magnetic core 8 has a pair of notches 8a so that it is exposed only to the sliding surface 9 to the outside. However, the present invention is not limited to such a configuration. . The magnetic core 8 is, for example, a metal magnetic thin film 4.
The width regulating groove 10 is formed outside the inclined surface 3 a of the non-magnetic substrate 3 on which the sliding surface 9 is formed.
May be formed so as to be exposed only to the outside.

In the magnetic head 1, the non-magnetic substrate 3 is made of a MnO-NiO-based non-magnetic material, but the present invention is not limited to such a configuration. The non-magnetic substrate 3 may be made of calcium titanate, barium titanate, zirconium oxide (zirconia), alumina, alumina titanium carbide, SiO ₂ , Zn ferrite, crystallized glass, high hardness glass, or the like.

In the magnetic head 1, the non-magnetic substrate 3 has the inclined surface 3a formed at an oblique angle with a predetermined angle. However, the inclined surface 3a is formed, for example, in a circular or polygonal shape. You may. However, the slope 3a is 45
It is desirable to form at an angle of about degrees. Thereby, the track width accuracy of the magnetic head 1 is improved.

Further, in the magnetic head 1, the metal magnetic thin film 4 is formed of a material exhibiting soft magnetism such as sendust (Fe-Al-Si alloy). However, the present invention is not limited to such a structure. Absent. The metal magnetic thin film 4 is made of, for example, Fe-Ta-N alloy, 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 4 is made of Fe, Co,
An alloy composed of one or more elements of Ni and one or more elements of P, C, B, Si, or
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, the metal magnetic thin film 4
May be a nitrided soft magnetic alloy or a carbonized soft magnetic alloy.

The metal magnetic thin film 4 may be formed of a single layer of magnetic metal thin film. However, it is preferable that a non-magnetic thin film layer and a magnetic thin film layer are alternately laminated. Thus, the magnetic head 1 can have high sensitivity in a higher frequency range.

The magnetic head 1 configured as above is
When reproducing a magnetic signal recorded on the magnetic recording medium, a signal magnetic field from the magnetic recording medium is applied around the front gap 14. When the direction of the applied signal magnetic field changes, the direction of the magnetic flux flowing through the magnetic core 8 changes. As a result, in the magnetic head 1, electromagnetic induction occurs, and a predetermined current flows through the thin-film coil 6.

When a magnetic signal is recorded on a magnetic recording medium using the magnetic head 1, a predetermined current is supplied to the thin-film coil 6. And this magnetic head 1
Then, the magnetic core 8 is generated by the magnetic field generated from the thin film coil 6.
A predetermined magnetic flux flows through the. Thereby, this magnetic head 1
Then, a leakage magnetic field is generated across the front gap 14. The magnetic head 1 records a magnetic signal by applying the leakage magnetic field to a magnetic recording medium.

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

The magnetic head 1 is formed on the same substrate by arranging the magnetic core halves 2 in a plurality of rows as described above. Then, the substrate is cut off for each row in which the plurality of magnetic core halves 2 are formed to form a magnetic core half block. The magnetic core half blocks are joined and integrated by metal diffusion bonding to form a magnetic head block. The magnetic head 1 is completed by separating the magnetic head block into individual magnetic heads 1.

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

Next, as shown in FIG.
For example, a plurality of magnetic core forming grooves 24 are formed with a grindstone or the like so as to have an angle of about 45 degrees with respect to one main surface 21a.
Are formed in parallel. Then, the magnetic core forming groove 24 formed in the first groove processing step forms the substrate 21 with the magnetic core forming groove 24.
A plurality of inclined surfaces 21b will be formed. Slope 2
Reference numeral 1b denotes an inclined surface 3a in the magnetic head 1.

The slope 21b formed here is
It may be circular or polygonal. Also, the inclined surface 21b
Is preferably about 25 to 60 degrees with respect to the plane of the substrate 21, but is more preferably about 35 to 50 degrees in consideration of prevention of pseudo gap and track width accuracy.
The magnetic core forming groove 24 formed by the first groove processing had a depth of 130 μm and a width of 150 μm.

Next, as shown in FIG. 5, a metal magnetic thin film 27 is formed on the entire surface of the substrate 21 on which the inclined surface 21b is formed. In this film forming step, the metal magnetic thin film 27
Is formed so that three metallic magnetic materials are laminated via a nonmagnetic layer. This metal magnetic thin film 27 is formed, for example, by a PVD method such as a magnetron sputtering method or the like.
The film is formed by a VD method or the like.

Further, the metal magnetic thin film 27 is not limited to the one having a plurality of metal magnetic layers, and may have a structure of a single metal magnetic layer. In order to obtain, it is desirable that the metal magnetic layer has a laminated structure in which the metal magnetic layer is divided into a plurality. Thereby, the metal magnetic thin film 27 can reduce the eddy current loss and obtain high sensitivity in a higher frequency band.

In this embodiment, the metal magnetic thin film 27
Has a structure in which 4 μm Fe-based microcrystalline films and 0.15 μm alumina are alternately laminated and has three sendust layers. When the metal magnetic thin film 27 is formed in a plurality of layers, alumina, Si
Materials such as O ₂ and SiO are used alone or as a mixture. The thickness of the non-magnetic layer is set to such an extent that insulation between adjacent metal magnetic layers can be obtained.

Next, as shown in FIG.
A second groove is formed on the surface on which the groove 7 is formed in a direction substantially orthogonal to the magnetic core forming groove 24. In the second groove processing step, a separation groove 28 formed to separate the magnetic cores 9 into a predetermined size and a magnetic gap formed in each of the magnetic cores 8 separated by the separation groove 28 are formed. Winding groove 2
9 are formed.

At this time, portions other than the metal magnetic thin film 27 formed on the inclined surface 21b, that is, the metal magnetic thin film 27 formed at the bottom of the magnetic core forming groove 24 are removed by grinding.

Here, the separation groove 28 is a groove for forming each magnetic core 8 by magnetically separating the magnetic core 8 in the front-rear direction on the substrate 21 and forming a closed magnetic path in each magnetic core 8. is there. Although two separation grooves 28 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 to be formed. In addition, the separation groove 28 must be formed so as to have a depth enough to completely cut the metal magnetic thin film 27 in order to magnetically separate the magnetic cores 8 arranged in the front-rear direction. is there. Specifically, the separation groove 28 has a depth of 150 μm from the bottom of the magnetic core formation groove 24, that is, a depth of 280 μm from the main surface 21 a of the substrate 21.

On the other hand, the winding groove 29 forms a recess 4 a formed in the metal magnetic thin film 4 in the magnetic head 1 described above. Therefore, the winding groove 29 forms a magnetic core 8 having the front butting surface 12 and the rear butting surface 13, and has a depth such that the metal magnetic thin film 27 is not cut to form the coil forming recess 16. It is necessary to form with. Therefore, the cross section of the metal magnetic thin film 27 is exposed on the surface of the winding groove 29.

The shape of the winding groove 29 is determined according to the lengths of the front butting surface 12 and the rear butting surface 13. Here, the width is set to about 140 μm, and And the length of the rear abutting surface 13 was 85 μm. The winding groove 29 may have such a depth that the metal magnetic thin film 27 is not cut. However, if the winding groove 29 is too deep, the magnetic path length becomes longer and the efficiency of magnetic flux transmission may be reduced. The depth of the winding groove 29 depends on the thickness of the thin-film coil 6 to be formed in a step to be described later.

Further, the shape of the winding groove 29 is not limited, but in the present embodiment, the side surface on the side of the front butting surface 12 is a 45-degree inclined surface. Thereby, the magnetic core 8 has a structure in which the magnetic flux is concentrated on the sliding surface 9, thereby improving the sensitivity. Further, the winding groove top 29a which is the top of the inclined surface is located at the gap 0 position which is the deepest portion of the magnetic gap in the magnetic head 1.

Next, as shown in FIG.
A portion of the metal magnetic thin film 27 formed on the inclined surface 21b is removed by grinding to form a notch 27a. In this removing step, the metal magnetic thin film 27 is retracted from the bottom of the inclined surface 21b on the sliding surface 9 side.
The end on the side that becomes the sliding surface 9 is cut out to form a notch 27a.
To form

The notch 27a is provided in the magnetic head 1
It serves as a notch 8 a of the magnetic core 8. The notch 27a is provided in advance to cut out a portion of the magnetic head 1 where the metal magnetic thin film 27 is cut out by the contact width regulating groove 10. The notch 27a is formed in the manufacturing process of the magnetic head 1 so that the magnetic core 8 is not exposed to the outside by the contact width regulating groove 10, and the magnetic core 8 is Only exposed to the outside.

In this removing step, the second
The notch 27a is formed using the winding groove top 29a formed by the groove forming step as a reference for positioning. Thus, in this removing step, the notch 27a can be formed with accurate positioning.

Therefore, in the metal magnetic thin film 27, the notch amount of the notch 27a is too small, and the magnetic core 8 is exposed from the end face of the contact width regulating groove 10, or the notch 27a
Does not degrade the electromagnetic conversion characteristics of the magnetic core 8 because the notch amount is too large. Therefore, in this removing step, the variation in the electromagnetic conversion characteristics of the magnetic head 1 and the defect rate can be suppressed, and the production efficiency can be improved.

In the present embodiment, the metal magnetic thin film 27 remains 90 μm along the inclined surface 21b on the sliding surface 9 side with the winding groove top 29a as a position reference, and the sliding of the notch 27a is performed. The end face opposite to the face 9 side and the winding groove top 29
The notch 27a was formed such that the distance from the groove a to the direction of the magnetic core forming groove 24 was 40 μm. Further, in the present embodiment, the notch 27a is formed by removing the metal magnetic thin film 27 using FIB, but the notch 27a is formed by using, for example, a fine processing technique using laser processing or lithography. May be.

Next, as shown in FIG. 8, the low-melting glass melted on one main surface 21a of the substrate 21 on which the magnetic core forming groove 24, the separation groove 28 and the winding groove 29 are formed as described above. Fill 30. Thereafter, the low-melting glass 30 is cooled and solidified, and the surface of the solidified low-melting glass 30 is subjected to a flattening process.

Next, as shown in FIG. 9, the solidified low melting point glass 30 is subjected to a grinding process using a grindstone or the like to form a terminal groove 31. The terminal groove 31 was formed so as to be located immediately above the above-described separation groove 28. The shape, width, and depth of the terminal groove 31 are not limited, but here, the width and depth are set to 100 μm. Then, a good conductor such as Cu is filled in the terminal groove 31 by plating or the like. After that, the flattening process is performed again.
The good conductor such as Cu filled in the terminal groove 31 serves as the external connection terminal 18 in the magnetic head 1 described above.

Next, as shown in FIG. 10, the low-melting glass 30 is subjected to an etching process to form a coil-forming recess 16 and a thin-film coil 6 is formed in the coil-forming recess 16. I do.

The recess 16 for forming a coil is formed in a substantially rectangular shape with the center of the rear abutting surface 13 being substantially at the center.
It is formed by performing an etching process on a portion excluding 3 and the coil connection terminal 17. The coil forming recess 16 has a groove 16a extending from one end to the terminal groove 31.

Then, a thin film coil 6 is formed in the coil forming recess 16. The thin film coil 6 has one end 6a disposed on a coil connection terminal 17 and a rear abutting surface 1.
It has a shape wound many times so as to draw a circle centered at 3. The thin-film coil 6 is drawn out into a groove 16 a formed at one end of the coil forming recess 16, and the other end 6 b is electrically connected to an external connection terminal 18 made of a good conductor filled in a terminal groove 31. Connecting.

When the thin film coil 6 is formed, first, the above-described coil shape is patterned by a photoresist. Next, Cu is formed in the coil forming recess 16.
Is formed into a thin film to a thickness of about 3 μm by a technique such as electrolytic plating. Then, by removing the photoresist, the thin film coil 6 having a patterned coil shape can be formed. In forming the thin-film coil 6, not only the electrolytic plating method described above but also a sputtering method or a vapor deposition method can be used.

Next, a protective layer (not shown) for protecting the thin-film coil 6 from contact with the outside air is formed. This protective layer is formed so as to fill the coil forming recess 16 in which the above-mentioned thin film coil 6 is formed. The protective layer is preferably formed of a non-magnetic insulating material that is not removed by the oxygen ashing.

Specifically, as the non-magnetic insulating material, Al
Examples thereof include oxides such as ₂ O ₃ , Ta ₂ O ₅ , SiO ₂ , ZrO ₂ , and TiO ₂ and inorganic substances such as glass. Here, as the protective film, Al ₂ O ₃ was sputtered to a thickness of 0.4 μm.
m was formed over the entire surface of the substrate 21. At this time, the protective film also covers the front butting surface 12 and the rear butting surface 13 which are exposed on one main surface of the substrate 21, but the portions covering these portions are removed in a step described later. Note that this protective film can be formed only in a predetermined region by using a so-called mask sputtering method or a lift-off method. Examples of the method for forming the protective film include, besides the sputtering method, an evaporation method and spin coating of coating type SiO ₂ .

Next, as shown in FIG. 11, side grooves 32, which are square grooves, are formed so as to cross the front butting surface 12 facing the one main surface in parallel. Thereafter, the substrate 21 in which the magnetic core halves 2 are formed in a plurality of parallel rows is cut so that one magnetic core half 2 and the other magnetic core half 2 are arranged in each row, and the magnetic core half block is formed. 33 are formed.

The side groove 32 is formed by grinding, and has a depth of 50 μm and a width of 400 μm, for example. When the side grooves 32 are formed, the side grooves 32
One end of the front abutting surface 12 is exposed on the side surface of. The side grooves 32 are formed to expose the upper end of the front butting surface 12 as a positioning index when the pair of magnetic core half blocks 33 are butted, as described later.

After the side grooves 32 are formed, the main surface 33a of the magnetic core half-block 33 is polished to make the main surface 33a a mirror surface. At this time, the front butting surface 1 covered with the protective film
2 and the rear butting surface 13 are exposed to the outside.

Next, as shown in FIG. 12, a pair of magnetic core half blocks 33 is accurately positioned and metal diffusion bonding is performed. At this time, first, a non-magnetic film 7 serving as a gap material for the magnetic core 8 and as an adhesive at the time of metal diffusion bonding is formed on one main surface 33a of each of the pair of magnetic core half blocks 33. I do. In the present embodiment, Au is formed as the nonmagnetic film 7 by a sputtering method. Then, the metal diffusion bonding is performed by accurately positioning the pair of magnetic core half blocks 33.

At this time, the upper ends of the front butting surfaces 12 facing the side grooves 32 are opposed to each other, so that accurate positioning is achieved. In this way, by correctly opposing the upper end of the front butting surface 12 facing the side groove 32, the rear butting surface 13 and the coil connection terminal 17 can be accurately faced.

Then, by applying a predetermined temperature and pressure to the pair of magnetic core half-blocks 33 butted against each other, the nonmagnetic films 8 are diffused, and the pair of magnetic core half-blocks 33 are joined and integrated. The manufactured magnetic head block 38 is manufactured.

Next, as shown in FIG. 13, the magnetic head block 38 is separated into individual magnetic heads 1.

At this time, first, the magnetic head block 38
Is cut in the longitudinal direction in order to expose a surface serving as a sliding surface 9 on which the magnetic recording medium slides. Then, the exposed surface of the magnetic head block 38 is subjected to cylindrical cutting so as to have a cylindrical shape. As a result, this surface becomes the sliding surface 9 of the magnetic head 1. Thereafter, the contact width regulating groove 10 is ground on the magnetic head block 38. The contact width regulating groove 10 is
Are formed at portions corresponding to both side surfaces of the sliding surface 9 of each magnetic head 1 separated from the magnetic head 1.

The magnetic head block 38 corresponds to FIG.
3 are separated into individual magnetic heads 1 by cutting at the portion indicated by the line BB.

In this embodiment, the sliding surface 9 is polished so that the front gap 14 of the magnetic head 1 has an azimuth angle of 20 degrees, and the contact width regulating groove 10 is ground. It is assumed that the cut surface of the magnetic head block 38 is inclined and separated. The magnetic head block 3
Reference numeral 8 denotes polishing of the sliding surface 9 described above,
The grinding process of 0 and the cutting process of separating the individual magnetic heads 1 may be performed so that the front gap 14 has a predetermined azimuth angle, and is not limited to the azimuth angle of 20 degrees.

In the present embodiment, the pair of magnetic core half blocks 33 are joined and integrated to form a magnetic head block 38 and then separated into individual magnetic heads 1. After the block 33 is separated into individual magnetic core halves, the magnetic head 1 may be formed by joining and integrating a pair of magnetic core halves.

Next, a method of manufacturing the second magnetic head according to the present invention will be described in detail with reference to the drawings. The method of manufacturing the second magnetic head differs from the method of manufacturing the first magnetic head described above in that the winding groove 29 and the notch 2 are formed.
The only difference is that the order of forming 7a is different. Therefore, in the following description of the method of manufacturing the second magnetic head, the description of the same steps as in the method of manufacturing the first magnetic head described above will be omitted.

In the second method for manufacturing a magnetic head,
Similarly to the above-described first magnetic head manufacturing method, as shown in FIG. 5, the non-magnetic substrate 21 on which the inclined surface 21b is formed is formed.
A metal magnetic thin film 27 is formed thereon. Then, in the first groove processing step, the separation groove 28 is formed in a direction substantially orthogonal to the magnetic core formation groove 24.

Next, as shown in FIG.
A part of the metal magnetic thin film 27 formed on the one inclined surface 21b is searched and removed to form a notch 27a. In this removing step, the metal magnetic thin film 2 is retracted from the bottom of the inclined surface 21b on the sliding surface 9 side.
7 is cut out at the end to be the sliding surface 9 so that the notch 27
a is formed.

The notch 27 a is provided in the magnetic head 1.
It serves as a notch 8 a of the magnetic core 8. The notch 27a is provided in advance to cut out a portion of the magnetic head 1 where the metal magnetic thin film 27 is cut out by the contact width regulating groove 10. The notch 27a is formed in the manufacturing process of the magnetic head 1 so that the magnetic core 8 is not exposed to the outside by the contact width regulating groove 10, and the magnetic core 8 is Only exposed to the outside.

In this embodiment, the metal magnetic thin film 27 is 90 μm thick along the inclined surface 21 b on the sliding surface 9 side.
The notch 27a was formed so as to remain. Further, in the present embodiment, the notch 27a is formed by removing the metal magnetic thin film 27 using FIB, but the notch 27a is formed by using, for example, a fine processing technique using laser processing or lithography. May be.

Next, as shown in FIG. 15, a winding groove 29 is formed so as to be substantially perpendicular to the magnetic core forming groove 24 with respect to the surface on which the metal magnetic thin film 27 is formed. This winding groove 29
Is for forming a concave portion 4a formed in the metal magnetic thin film 4 in the magnetic head 1.

The shape of the winding groove 29 is not limited, but in the present embodiment, the front butting surface 1
The two side surfaces were inclined at 45 degrees. Thereby, the magnetic core 8 has a structure in which the magnetic flux is concentrated on the sliding surface 9, thereby improving the sensitivity. Further, the winding groove top 29a which is the top of the inclined surface is located at the gap 0 position which is the deepest portion of the magnetic gap in the magnetic head 1.

In this winding groove forming step, the winding groove 29 is formed using the end face of the notch 27a formed in the previous removing step as a reference for positioning. Thereby, the winding groove 29 can be formed while maintaining the relative position with respect to the notch 27a accurately. Therefore, it is possible to prevent the gap depth of the front gap 14 of the magnetic head 1 from being formed at a predetermined distance due to the formation of the winding groove 29 shifted from a desired position. Therefore, in this winding groove forming step, the variation in the electromagnetic conversion characteristics of the magnetic head 1 and the defective rate can be suppressed, and the production efficiency can be improved.

In this embodiment, the notch 2
The winding groove 29 was formed such that the distance in the direction of the magnetic core forming groove 24 between the end face of the side 7a opposite to the sliding surface 9 side and the winding groove top 29a was 40 μm.

In this embodiment, the winding groove 2
9 was formed to have a width of about 140 μm, a length of the front butting surface 12 being 30 μm, and a length of the rear butting surface 13 being 85 μm. The winding groove 29 may have a depth that does not cut the metal magnetic thin film 27.
If it is too deep, the magnetic path length becomes longer, and the efficiency of magnetic flux transmission may decrease. Therefore, in the present embodiment, the depth of the winding groove 29 is set to 20 μm.

Next, as shown in FIG. 8, the substrate 21 on which the magnetic core forming groove 24, the separation groove 28 and the winding groove 29 are formed.
Is filled with the melted low-melting glass 30 on one main surface 21a. In the second magnetic head manufacturing method, the following steps are the same as the above-described first magnetic head manufacturing method, and the description thereof will be omitted.

Hereinafter, the magnetic head 1 manufactured according to the embodiment of the present invention and the magnetic head 100 in which the metal magnetic thin film 4 is exposed from the end face 10a of the contact width regulating groove 10 as shown in FIG. Will be described.
The magnetic head 100 has the same configuration as that of the magnetic head 1 except that the magnetic core 8 is exposed from the end surface of the contact width regulating groove 10. Therefore, in FIG. The same as above.

First, in the first measurement test, the magnetic head 1 and the magnetic head 100 were connected to a DVC (Digital).
The film was adhered to a head base for a Video Cassette and subjected to a 240-cycle condensation test under the following conditions.

Condensation test 1 cycle: -40 ° C 30min / + 85 ° C
30 min As a result of the dew condensation test, no rust was observed on the metal magnetic thin film 4 of the magnetic head 1. However, in the magnetic head 100, rust was observed at the bottom of the contact width regulating groove 10 at a rate of 0.5%.

Therefore, in the magnetic head 1, the metal magnetic thin film 4 is not exposed from the end face 10 a of the contact width regulating groove 10, but is exposed only on the sliding face 9.
It can be seen that the corrosion resistance is improved as compared with the magnetic head 100.

Next, in the second measurement test, the magnetic head 1 and the magnetic head 100 are adhered to a DVC head base, and the external connection terminals 18 of each magnetic head are connected.
An electromagnetic conversion characteristic test was performed under the following conditions by electrically connecting the external terminal plate of the head base to the external terminal board by wire bonding.

Electromagnetic conversion characteristic test Measuring device: Drum tester Magnetic recording medium: Adv. ME tape Relative speed: 10.2 m / s As a result of this electromagnetic conversion characteristic test, the magnetic head 100
A variation in reproduction output of about 3σ = 4 dB was observed. Further, in the magnetic head 1, the variation of the reproduction output is 1
It was within dB. The result is that the processing accuracy of the hit width regulating groove 10 is approximately ± 10 μm, and that the magnetic core 8 was formed with high precision in the magnetic head 1 without depending on the working of the hit width limiting groove 10. Conceivable.

In the magnetic head 100, the shape of the magnetic core 8 is determined by notching the metal magnetic thin film 4 by the contact width regulating groove 10. Therefore, the electromagnetic conversion characteristics of the magnetic head 100 are determined by the processing accuracy of the contact width regulating groove 10. However, the magnetic head 1 is formed by removing in advance a portion cut out by the contact width regulating groove 10 of the metal magnetic thin film 4 by the notch 8a. Therefore, in the magnetic head 1, the shape of the magnetic core 8 is formed with high precision irrespective of the processing accuracy of the contact width regulating groove 10. Therefore, the magnetic head 1 can suppress variations in electromagnetic conversion characteristics as compared with the magnetic head 100, and can improve production efficiency.

[0097]

As described above, the magnetic head according to the present invention is configured such that the metal magnetic thin film forming the magnetic core is exposed only on the sliding surface. Therefore, such a magnetic head can have improved corrosion resistance even when the content of Fe or the like in the metal magnetic thin film is increased to increase the saturation magnetic flux density. Therefore, such a magnetic head can record and reproduce a recording signal even on a magnetic recording medium having a high coercive force and can have improved corrosion resistance.

In the method of manufacturing a magnetic head according to the present invention, the metal magnetic thin film is cut out only on the sliding surface by cutting out a part of the metal magnetic thin film with reference to the top of the winding groove. It is formed so as to be exposed. Therefore, according to the method for manufacturing a magnetic head, when a part of the metal magnetic thin film is cut out, the processing accuracy can be improved. Therefore, according to such a method of manufacturing a magnetic head, it is possible to suppress variations in the electromagnetic conversion characteristics of the magnetic head and improve production efficiency.

Further, in the method of manufacturing a magnetic head according to the present invention, a winding groove is formed with reference to a notch formed at the sliding surface side end of the metal magnetic thin film, and the metal magnetic thin film is slid. It is formed so as to be exposed only on the moving surface. Therefore, according to the method for manufacturing a magnetic head, the processing accuracy when forming the winding groove can be improved. Therefore, according to the method for manufacturing a magnetic head, the defective rate of the magnetic head can be suppressed, and the production efficiency can be improved.

[Brief description of the drawings]

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

FIG. 2 is a perspective view of a main part showing a 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 same method, and is a perspective view showing a substrate on which first groove processing has been performed.

FIG. 5 is a view for explaining the same method, and is a perspective view showing a substrate on which a metal magnetic thin film is formed.

FIG. 6 is a view for explaining the same method, and is a perspective view showing a substrate on which a second groove processing has been performed.

FIG. 7 is a diagram for explaining the same method, and is an enlarged view of a main part showing a cutout portion formed in the metal magnetic thin film.

FIG. 8 is a diagram for explaining the same method, and is a perspective view showing the substrate in a state where each groove is filled with low-melting glass.

FIG. 9 is a diagram for explaining the same method, and is a perspective view showing a substrate in which terminal grooves are formed in low-melting glass.

FIG. 10 is a view for explaining the same method, and is a perspective view of a principal part showing a substrate on which a concave portion for forming a coil is formed.

FIG. 11 is a diagram for explaining the same method, and is a perspective view showing a magnetic core half block.

FIG. 12 is a diagram for explaining the same method, and is a perspective view showing a state where a pair of magnetic core half blocks are butted.

FIG. 13 is a diagram for explaining the same method, and is a perspective view showing a magnetic head block.

FIG. 14 is a diagram for explaining the same method, and is an enlarged view of a main part showing a cutout portion formed in the metal magnetic thin film.

FIG. 15 is a view for explaining the same method, and is a perspective view showing a substrate on which a winding groove is formed.

FIG. 16 is a perspective view of an essential part showing a magnetic head in which a metal magnetic thin film is formed so as to be exposed from an end face of a contact width regulating groove.

[Explanation of symbols]

1 magnetic head, 2 magnetic core halves, 3 non-magnetic substrate,
3a inclined surface, 4 metal magnetic thin film, 4a recess, 5 low melting point glass, 7 non-magnetic film, 8 magnetic core, 8 notch,
9 sliding surface, 10 width limit grooves, 14 front gap, 15 back gap

Claims (4)

[Claims] 1. A pair of magnetic core halves having a metal magnetic thin film formed obliquely on a substrate, a concave portion in which a thin film coil is formed, and a butted surface flattened by a nonmagnetic material. A magnetic head in which a magnetic gap is formed by abutting the front butting surfaces of the metal magnetic thin films so as to face each other with a non-magnetic material interposed therebetween. A magnetic head characterized in that it is exposed to the outside only on the moving surface. 2. The metal magnetic thin film has cutouts located on both sides on the sliding surface side so as to be exposed only on the sliding surface. 1
The magnetic head as described. 3. A pair of magnetic core halves formed by forming a metal magnetic thin film obliquely on a substrate, forming a winding groove in which a thin film coil is formed, and flattening an abutting surface with a nonmagnetic material. In a method for manufacturing a magnetic head in which a front butting surface of the metal magnetic thin film is opposed to each other via a non-magnetic material to form a magnetic gap, a winding groove forming step of forming the winding groove; A step of notching the end of the metal magnetic thin film on the sliding surface side on which the magnetic recording medium slides, with the top of the winding groove on the front abutting surface side as a position reference, thereby removing the metal magnetic thin film. Is formed so as to be exposed outward only on the sliding surface. 4. A pair of magnetic core halves formed by forming a metal magnetic thin film obliquely on a substrate, forming a winding groove in which a thin film coil is formed, and flattening an abutting surface with a nonmagnetic material. A method of manufacturing a magnetic head, wherein a magnetic gap is formed by abutting front butting surfaces of metal magnetic thin films so as to face each other via a non-magnetic material, wherein a sliding surface on which a magnetic recording medium of the metal magnetic thin film slides is provided. A removing step of notching a side end, and a winding groove forming step of forming the winding groove with the notch of the metal magnetic thin film formed in the removing step as a position reference, A method for manufacturing a magnetic head, wherein a thin film is formed so as to be exposed outward only on the sliding surface.