JP2000293812A - Magnetic head and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To narrowly form the track width with a high precision. SOLUTION: A metallic magnetic film 4 formed on a pair of magnetic core half bodies 2 is notched downward from a butting face 2a of these magnetic core half bodies 2. Thus, a track width Tw of a magnetic head 1 is formed more narrowly than a track width Tw0 obtained by producing the magnetic head without notching the metallic magnetic film. In this case, the angle of incidence of an ion beam is set to 24 to 35 deg.C in the etching process.

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. Various types of magnetic heads such as a metal-in-gap (MIG) type magnetic head and a laminated magnetic head have been proposed and put into practical use.

[0003] In order to cope with higher recording density and digitization, a magnetic head that can exhibit good electromagnetic conversion characteristics in a higher frequency band is desired. Also, VT
Since the magnetic head for R needs to be mounted on a small drum in order to cope with miniaturization and high performance of the device, it is desired to reduce the size.

The above-mentioned MIG type magnetic head is not suitable for use in a high frequency band because of its large impedance. In addition, in the stacked magnetic head, as the track width decreases with the increase in recording density, it is necessary to reduce the thickness of the metal magnetic thin film constituting the magnetic path, so that the reproduction efficiency is reduced. Also, there is a limit to the miniaturization of the head.

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

In this bulk thin film magnetic head, a pair of magnetic core halves each having a metal magnetic thin film formed on a nonmagnetic substrate are joined and integrated with each other via the nonmagnetic film. Thus, in the bulk thin film magnetic head, these metal magnetic thin films constitute a magnetic core, and a magnetic gap is formed by the nonmagnetic film. The bulk thin-film magnetic head has a coil-forming recess 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. .

[0007]

By the way, in recent years, in the field of magnetic recording, higher recording density of magnetic signals has been further promoted. For this reason, magnetic heads are increasingly required to accurately record and reproduce fine magnetic signals in response to higher recording densities. Have been.

In the conventional bulk thin film type magnetic head, in order to form a magnetic gap with a narrow track width, a metal magnetic thin film exposed at a joint surface between a pair of magnetic core halves is required.
It had been subjected to mechanical grinding. However, according to this mechanical grinding method, the track width is 13 μm.
Was the limit.

In the manufacturing process of a bulk thin film magnetic head, generally, a large number of magnetic heads are formed in a matrix on a substrate material, and a large number of magnetic heads are processed and manufactured at a time by using a thin film forming technique. This improves production efficiency. However, in the mechanical grinding as described above, since it is necessary to individually perform processing on each magnetic head, there has been a problem that the processing time for such a large number of magnetic heads increases. Further, there is a problem that it is difficult to perform uniform grinding on each magnetic head, and it is difficult to efficiently manufacture a magnetic head having a narrow track width with high accuracy.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic head adapted to a high recording density by forming a track width to be narrow with high precision. Another object of the present invention is to provide a method of manufacturing a magnetic head having a narrow track width with high precision and excellent production efficiency.

[0011]

A magnetic head according to the present invention has a metal magnetic thin film formed obliquely on a substrate, a concave portion in which a thin film coil is formed, and an abutting surface made of a nonmagnetic material. A pair of flat magnetic core halves is provided. The pair of magnetic core halves abut each other such that the front butting surfaces of the metal magnetic thin films face each other via the nonmagnetic thin film to form a magnetic gap. Further, at least one of the metal magnetic thin films is formed by cutting out at least one side of both side portions in the track width direction exposed to the abutting surface from the abutting surface.

In the magnetic head configured as described above, the width of the magnetic gap in the track direction is narrowed because at least one of the metal magnetic thin films is cut out in the track width direction at the abutting surface. It becomes. This enables the magnetic head to accurately record and reproduce fine magnetic signals in response to the increase in recording density.

Further, according to the method of manufacturing a magnetic head of the present invention, a metal magnetic thin film is formed obliquely on a substrate,
A pair of magnetic core halves formed by forming a thin-film coil and flattening the butted surface with a non-magnetic material are joined together such that the front butted surfaces of the metal magnetic thin film face each other via the non-magnetic thin film. This is a method for manufacturing a magnetic head for forming a gap. Then, through a resist forming step and an etching step, the metal magnetic thin film is formed narrow in the track width direction on the abutting surface. In the resist forming step, a resist film is formed on at least one of the pair of magnetic core halves on the metal magnetic thin film exposed at the abutting surface so as to be narrower than the metal magnetic thin film. In the etching step, the metal magnetic thin film is subjected to an etching process with the width of the resist film.

According to the method of manufacturing a magnetic head as described above, the width of the magnetic gap in the track width direction can be narrowed with high precision by the resist process and the etching process, which are thin film forming techniques. In addition, thereby, for example, when a large number of magnetic heads are formed on a substrate, processing can be performed at once, and processing can be performed on a large number of magnetic heads in a short time. Therefore, it is possible to efficiently produce a magnetic head capable of accurately recording and reproducing a fine magnetic signal corresponding to a higher recording density.

[0015]

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.

A magnetic head 1 to which the present invention is applied comprises a pair of magnetic core halves 2 joined by metal diffusion bonding. The pair of magnetic core halves 2 are made of MnO—NiO
A non-magnetic substrate 3 made of a non-magnetic material, a metal magnetic thin film 4 formed on an inclined surface 3a of the non-magnetic substrate 3, and a metal magnetic thin film 4 formed on the non-magnetic substrate 3 so as to cover the metal magnetic thin film 4. And low melting point glass 5. Further, 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, the metal magnetic thin film 4 forms a magnetic core 8 as shown in FIG. 2 in a state where the pair of magnetic core halves 2 are joined via the nonmagnetic thin film 7. In FIG. 2, the thin-film coil 6 is not shown. The magnetic head 1 reproduces a signal magnetic field recorded on the magnetic recording medium or records the signal magnetic field on the magnetic recording medium by sliding the magnetic recording medium in a direction indicated by an arrow A in FIG.

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 sliding direction of the magnetic recording medium indicated by an 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 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 material exhibiting soft magnetism such as Sendust (Fe-Al-Si alloy). The metal magnetic thin film 4
The non-magnetic substrate 3 is formed on an inclined surface 3 a which is formed obliquely at a predetermined angle. For this reason, the magnetic core 8
Are a pair of magnetic core halves 2 on which a metal magnetic thin film 4 is formed.
Are joined obliquely to the sliding direction A of the magnetic recording medium as shown in FIG.

The metal magnetic thin film 4 has a concave portion 4a at a substantially central portion of the end surface on the side to which the magnetic core half 2 is bonded. For this reason, the metal magnetic thin film 4 has a front butting surface 11 and a rear butting surface 12 which are separated and exposed by the low melting point glass 5 filled in the concave portion 4a at the joining surface 2a of the magnetic core half 2. Becomes The front butting surfaces 11 of the pair of magnetic core halves 2 are
To form a front gap 13. The rear butting surfaces 12 of the pair of magnetic core halves 2 are butted with the non-magnetic thin film 7 therebetween to form a back gap 14.

The metal magnetic thin film 4 has a bonding surface 2a
And a coil forming recess 15 in which the thin film coil 7 having the rear butting surface 12 substantially at the center is formed. A coil connection terminal 16 is formed in the coil forming recess 15 near the rear butting surface 12. Thin film coil 6
Is formed in the coil forming recess 15, and the end on the center side is connected to the coil connection terminal 16.

The coil connection terminals 16 are formed with their heights adjusted so as to form the same surfaces as the joint surfaces 2a of the pair of magnetic core halves 2. And the magnetic head 1
In the above, when the pair of magnetic core halves 2 are joined, the pair of coil connection terminals 16 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 magnetic recording medium. External connection terminals 17 are formed on the pair of magnetic core halves 2 at portions where the thin film coil 6 is led out. The outer peripheral ends of the thin film coil 6 are connected to the external connection terminals 17, respectively.

These external connection terminals 17 are exposed to the side surface of the magnetic head 1 so that
Has the function of electrically connecting The pair of external connection terminals 17 are connected to each other so that a short circuit does not occur.
They are formed at positions where they do not contact each other when the pair of magnetic core halves 2 are joined.

Incidentally, in the magnetic head 1, FIG.
As shown in (1), the depth B, which is the depth of the front gap 13 from the sliding surface, is one of the important factors that determine the head characteristics. The magnetic head 1 uses a front gap 13 to accurately and easily read the depth B.
Is formed as a depth marker for determining the zero depth position 13a.

The groove 18 is formed on the joint surface 2a of the pair of magnetic core halves 2 at the top of the recess 4a of the metal magnetic thin film 4 on the front gap 13 side. The groove 18 is formed so that both ends face both side surfaces of the magnetic head 1, and is formed parallel to the sliding surface 9. Therefore, the groove portion 18 is formed so as to cut out the end of the pair of magnetic core halves 2 opposite to the sliding surface 9 of the front butting surface 11. Therefore, the side edge 18 a of the groove 18 on the sliding surface 9 side always coincides with the zero depth position 13 a of the front gap 13. In other words, in the magnetic head 1, the distance from the sliding surface 9 to the side edge 18a of the groove 18 is the depth B.

Therefore, in the magnetic head 1, the depth B of the front gap 13 can be adjusted with high precision by polishing the sliding surface 9 while checking the distance from the sliding surface 9 to the side edge 18a of the groove 18 from the side. Can be adjusted. Therefore, the magnetic head 1 has the front gap 13
The head efficiency can be improved by polishing the sliding surface 9 so that the depth B becomes smaller.

In this embodiment, the groove 18
Preferably, the distance between the side edge 18a on the sliding surface 9 side and the end of the front abutting surface 11 on the side opposite to the sliding surface 9 is preferably 15 μm or less, and more preferably 7 μm or less. If this distance exceeds 15 μm, the length of the front butting surface 11 cut out by the groove 18 increases, so that the lower part of the front gap 13 which does not significantly contribute to the core efficiency, Deposition increases. For this reason, the core efficiency per inductance may be degraded.

The depth of the groove 18 toward the substrate 21 is preferably 2 to 15 μm, and more preferably 5 to 10 μm.
μm is desirable. The magnetic head 1 has a groove 18
Is less than 2 μm, the core efficiency may be deteriorated due to the influence of the leakage of the magnetic flux in the groove 18. Further, in the magnetic head 1, when the depth of the groove 18 exceeds 15 μm, the magnetic core 8 may be cut off by the groove 18, and the core efficiency may be deteriorated.

In the magnetic head 1, as shown in FIG. 4, the width of the front gap 13 in the direction perpendicular to the sliding direction A of the magnetic recording medium is the track width Tw.
It has been. In other words, the metal magnetic thin films 4 formed on the pair of magnetic core halves 2 are butted against each other at the butting surfaces 2 a of the magnetic core halves 2, and the front butt forming the front gap 13 is formed. Face 11
Is a track width Tw in the direction perpendicular to the sliding direction A of the magnetic recording medium. In addition, FIG.
FIG. 2 is an enlarged view of a main part near a front gap 13 when the magnetic head 1 is viewed from a sliding surface 9 side of a magnetic recording medium.

The metal magnetic thin film 4 is made of the magnetic core half 2
Both sides in the track width Tw direction exposed to the butting surface 2a are cut out downward from the butting surface 2a. Thereby, the track width Tw of the magnetic head 1 is obtained.
, Compared to the track width Tw ₀ in the case of forming without notching the metal magnetic thin film 4 is formed in a narrow. Therefore, the magnetic head 1 can accurately record and reproduce fine magnetic signals in response to the increase in recording density.

In the magnetic head 1, the notch 19 formed by cutting the metal magnetic thin film 4 as described above is filled with a non-magnetic insulating material. Thereby, it is possible to prevent the magnetic recording medium sliding on the sliding surface 9 from being damaged by the edge of the notch 19. As the non-magnetic insulating material filling the notch 19, for example, Al ₂ O ₃ , Si
Oxides such as O ₂ , Ta ₂ O ₅ , Cr ₂ O ₃ , TiO ₂ , Cr,
Metals such as Pr, Au, and Ag can be used.

FIG. 4 shows a case where the metal magnetic thin films 4 formed on the pair of magnetic core halves 2 are butted with different widths from each other. In this case, in the magnetic head 1, the track width Tw is the width of the thinner metal magnetic thin film 4 in the direction perpendicular to the sliding direction A of the magnetic recording medium.

In the magnetic head 1, a pair of magnetic core halves 2
It is desirable that the metal magnetic thin films 4 formed at the same time are formed so as to have the same width and butted without any step. Thereby, the recording / reproducing characteristics can be improved. However, it is difficult to accurately align and join the metal magnetic thin films 4 having the same width, and even if there is a slight deviation, the track width is reduced by the deviation.

Therefore, in the magnetic head 1, as shown in FIG. 4, the front gap 13 is formed by abutting the metal magnetic thin films 4 having widths slightly different from each other, so that the desired track width Tw can be reliably obtained. Can be.

In the magnetic head 1, only one of the metal magnetic thin films 4 formed on the pair of magnetic core halves 2 may be cut out as described above. Thereby, the alignment of the pair of magnetic core halves 2 can be further facilitated. Further, in the present embodiment, both sides in the track width Tw direction of the metal magnetic thin film 4 are cut, but only one of the sides may be cut.

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 is made of calcium titanate, barium titanate, zirconium oxide (zirconia), alumina,
It may be made of alumina titanium carbide, SiO ₂ , Zn ferrite, crystallized glass, high hardness glass, or the like.

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). It is not limited. The metal magnetic thin film 4 is made of, for example, an Fe-Ta-N alloy, an Fe-Al alloy, an Fe-Si-Co alloy, an Fe-Ga-Si alloy,
e-Ga-Si-Ru alloy, Fe-Al-Ge alloy, F
e-Ga-Ge alloy, Fe-Si-Ge alloy, Fe-C
It may be made of a crystalline alloy such as an o-Si-Al alloy or an Fe-Ni alloy. Alternatively, metal magnetic thin film 4
Represents one or more elements of Fe, Co, Ni and P, C,
Alloy consisting of one or more elements of B and Si, or Al, Ge, Be, Sn, In, Mo,
Metal-metalloid amorphous alloys typified by alloys containing W, Ti, Mn, Cr, Zr, Hf, Nb, etc .; It may be made of an amorphous alloy such as a metal-based amorphous alloy. Further, the metal magnetic thin film 4 may be a nitride-based soft magnetic alloy or a carbide-based soft magnetic alloy.

Further, the metal magnetic thin film 4 may be constituted by a metal magnetic thin film composed of a single layer, but it is preferable that a nonmagnetic 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.

In the magnetic head 1, the groove 18 is formed in each of the pair of magnetic core halves 2.
It is not limited to such a configuration. Groove 18
May be formed on at least one of the pair of magnetic core halves 2.

Further, it is desirable that the groove 18 be filled with a non-magnetic material. The magnetic head 1 has a groove 18
Is formed as a gap, the depth B of the front gap 13 is worn out due to wear or the like during use of the head, and the groove 18 is exposed on the sliding surface 9. At this time, the sliding surface 9
In this case, a sharp edge of the groove 18 is formed, and the magnetic recording medium sliding on the sliding surface 9 is damaged. The magnetic head 1 can prevent such damage to the magnetic recording medium by filling the groove portion 18 with a non-magnetic material.

As the nonmagnetic material to be filled in the groove 18, it is desirable to use a material different from the low-melting glass 5 so that the boundary between the groove 18 and the low-melting glass 5 can be identified. Specifically, a material similar to the above-described non-magnetic material filling the notch 19 can be used.

In the present embodiment, the cross section of the groove 18 formed in each of the pair of magnetic core halves 2 has a semicircular shape, but may have a polygonal shape, for example.

The magnetic head 1 configured as described above
When reproducing a magnetic signal recorded on the magnetic recording medium, a signal magnetic field from the magnetic recording medium is applied around the front gap 13. 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 current corresponding to the signal magnetic field flows through the thin-film coil 6.
The magnetic head 1 reads the signal magnetic field from the magnetic recording medium by detecting the current generated in the thin film coil 6 via the external connection terminal 17.

When recording a magnetic signal on a magnetic recording medium using the magnetic head 1, a current corresponding to the recording signal is supplied to the thin-film coil 6 via the external connection terminal 17. As a result, the magnetic field generated from the thin-film coil 6 causes a magnetic flux corresponding to the recording signal to flow through the magnetic core 8, and a leakage magnetic field is generated across the front gap 13 of the magnetic core 8. The magnetic head 1 records a magnetic signal by applying the leakage magnetic field to a magnetic recording medium.

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

When manufacturing the magnetic head 1, first, a plurality of magnetic core halves 2 are formed on the same substrate in a plurality of rows. Next, the substrate is separated for each row in which the plurality of magnetic core halves 2 are formed, and a magnetic core half block is manufactured. Next, a magnetic head block is manufactured by joining and integrating the magnetic core half blocks by metal diffusion bonding. Then, the magnetic head block is cut into individual magnetic heads 1 to complete the magnetic head 1. Hereinafter, these steps will be described step by step.

First, as shown in FIG. 5, 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, for example, a thickness of about 2 mm and a length and a width of about 30 mm.

Next, as shown in FIG.
For example, 45 is applied to one main surface 21a by a grindstone or the like.
A plurality of magnetic core forming grooves 24 are formed parallel to each other so as to have an angle of ゜. Thus, a plurality of inclined surfaces 21b are formed in the substrate 21 by the magnetic core forming grooves 24 formed by the first groove processing.

The inclined surface 21b formed here is:
The shape may be an arc or a polygon. Also, the inclined surface 21b
Preferably has an inclination angle of about 25 to 60 ° with respect to the main surface of the substrate 21, but it is more preferable to have an inclination angle of about 35 to 50 ° in consideration of prevention of pseudo gap and track width accuracy. desirable. In the present embodiment, the depth of the magnetic core forming groove 24 is set to 130 μm and the width is set to 150 μm.

Next, as shown in FIG. 7, the metal magnetic thin film 2 is formed on the entire surface of the substrate 21 on which the inclined surface 21b is formed.
7 is formed. In this film forming step, the metal magnetic thin film 27 is formed such that three layers of metal magnetic materials are laminated via a nonmagnetic layer. The metal magnetic thin film 27 is formed, for example, by magnetron sputtering, MBE (Molecula).
PVD (Physical Vap) such as r Beam Epitaxy method and evaporation method
or Deposition) or CVD (Chemical Vapor Deposi)
) method.

Further, the metal magnetic thin film 27 is not limited to the one having a plurality of metal magnetic layers, and may be configured to have a single metal magnetic layer. However, high sensitivity is obtained in a higher frequency band. For this reason, it is desirable that the metal magnetic layer has a laminated structure 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
Is composed of three layers of Fe-Al-Si alloy (Sendust) 4 μm and alumina 0.15 μm alternately laminated,
-It has the structure which has a Si alloy layer. When the metal magnetic thin film 27 is formed into a plurality of layers, materials such as alumina, SiO _2, and SiO are used alone or in combination as the non-magnetic layer. 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, a separation groove 28 formed for separating the magnetic core 8 having a predetermined size and a winding for forming the thin film coil 6 on each magnetic core 8 separated by the separation groove 28 are formed. A line groove 29 is formed.

At this time, the metal magnetic thin film 27 formed on the portion other than the inclined surface 21b, that is, the metal magnetic thin film 27 formed on the bottom of the magnetic core forming groove 24 is 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 normal time path in each magnetic core 8. is there. Although two separation grooves 28 are formed in the example of FIG. 8, the separation grooves 28 need to be provided by the number of rows of the magnetic core halves 2 to be formed. In order to magnetically separate the magnetic cores 8 arranged side by side in the front-rear direction, the separation grooves 28 need to be formed to have a depth enough to completely cut the metal magnetic thin film 27. There is. 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 is for forming the concave portion 5 a in the magnetic core 8 in the magnetic head 1 in the magnetic magnetic thin film 27. Therefore, the winding groove 29 forms a magnetic core 8 having the front butting surface 11 and the rear butting surface 12, and has such a depth that the metal magnetic thin film 27 is not cut to form the coil forming recess 15. 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 11 and the rear butting surface 12. In the present embodiment, the width of the winding groove 29 is about 140 μm.
The length of the front butting surface 11 was 30 μm, and the length of the rear butting surface 12 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 formed in a step described later, but is set to 20 μm in the present embodiment.

Further, the shape of the winding groove 29 is not limited, but in the present embodiment, the side surface on the front butting surface 11 side is an inclined surface 29a having an angle of 45 °. Thereby, the magnetic core 8 has a structure in which the magnetic flux is concentrated on the sliding surface 9, and the sensitivity of the magnetic head 1 can be improved.

Next, as shown in FIG. 9, 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 molten low-melting glass 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.

The low melting point glass 30 has a viscosity at a temperature of 10 ² to 1 at which the metal magnetic thin film 27 exhibits good soft magnetic properties.
0 ⁶ Pa · s, more preferably 10 ³ to 1
It is desirable that a 0 ⁵ Pa · s. Thereby, when the substrate 21 is filled with the molten low melting point glass 30, it is possible to prevent the metal magnetic thin film 27 from losing soft magnetic properties.

When flattening the low-melting glass 30, it is desirable that the width of exposing the substrate 21 be smaller than the width of the innermost circumference of the thin-film coil 6. Thereby, when performing an etching process in a later step, the substrate 21
And the low melting point glass 30 can prevent generation of a step due to a difference in etching rate.

Next, as shown in FIG. 10, a terminal groove 31 is formed by subjecting the solidified low-melting glass 30 to grinding using a grindstone or the like. This terminal groove 31
It is formed so as to be located directly above the above-mentioned separation groove 28.
Further, in the present embodiment, the width and the depth of the terminal groove 31 are set to 1
It was set to 00 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 becomes the external connection terminal 17 in the magnetic head 1 described above.

Next, as shown in FIG. 11, a resist film 32 is formed on the low melting point glass 30 where the metal magnetic thin film 27 is exposed.
Is formed. FIG. 11A is a plan view of the substrate 21 as viewed from the low melting point glass 30 side, and FIG.
It is sectional drawing in CC line of 1 (a). Further, the resist film 32 is formed by the metal magnetic thin film 2 in an etching step described later.
7 is formed in order to form the front butting surface 11 into a thin shape.

The resist film 32 is formed on the entire surface of the low-melting glass 30 and then patterned to have a pair of openings 32 a near each metal magnetic thin film 27 exposed from the low-melting glass 30. Formed. The resist film 32 is formed such that the bridge 32b separating the pair of openings 32a is located on the front butting surface 11 of the metal magnetic thin film 27. That is, the pair of openings 32
Are formed at positions where both side edges of the front butting surface 11 of the metal magnetic thin film 27 are opened.

In the resist film 32, an ion beam irradiated in an etching step described later concentrates on a first root portion 32c, which is an end on the side of the rear butting surface 12 of the bridge-like portion 32b. As the process proceeds, the resist pattern is finely deformed. Therefore, it is desirable that the first root portion 32c of the resist film 32 be formed at a position closer to the rear butting surface 11 than the end 11a of the front butting surface 11 closer to the rear butting surface 12. Thus, the metal magnetic thin film 27 can be etched with high precision in an etching step described later.

In the resist film 32, the second base portion 32d, which is the end opposite to the rear butting surface 12 of the bridge-like portion 32b, that is, the end portion on the side to be the sliding surface 9, is shown in FIG.
As shown in FIG. 1A, the metal magnetic thin film 27 may be formed on the front butting surface 11. The resist pattern is also deformed at the second base portion 32d in the same manner as described above, and the etching accuracy is degraded. However, when the substrate 21 is cut in a later step, the sliding surface of the front abutting surface 11 is reduced. This is because the 9 side becomes unnecessary.

The resist film 32 can be formed with a resist pattern having the above-mentioned shape by using, for example, a photolithography technique. Also, the resist film 32
May be either a positive type or a negative type.

In the present embodiment, it is preferable that the resist film 32 be formed to have a thickness of 13 μm or more in consideration of a thickness that will be etched in an etching step described later. In consideration of the width accuracy of the bridge 32b, it is more preferable to form the bridge 32b with a thickness of about 14 to 15 μm. Further, the bridge-like portion 32 b is formed by the substrate 21 and the metal magnetic thin film 27
Is preferably formed around a position shifted by 10 to 16 μm from the boundary portion to the metal magnetic thin film 27 side.

Next, the substrate 2 on which the resist film 32 is formed
1 is subjected to an etching process. In this etching step, the width of the resist film 32 is substantially the same as that of the bridge-like portion 32b.
The purpose is to cut both side edges of the metal magnetic thin film 27 in the thickness direction of the substrate 21. As a result, as shown in FIG. 12, the metal magnetic thin film 27 has a side wall 27a cut out substantially perpendicularly to the substrate 21 from the front butting surface 11. Further, the low melting point glass 30 is etched to have the concave portion 30a.

As a result, in the magnetic head 1 finally completed, the track width Tw is formed to be narrow.
In response to the increase in the recording density of the magnetic recording medium, it is possible to accurately record and reproduce fine magnetic signals. Specifically, the track width Tw of the magnetic head 1 is set to 4.0 ± 0.2 μm.
m can be formed with high accuracy. Therefore, the magnetic head 1 can accurately and stably record and reproduce finer magnetic signals as compared with a magnetic head having a track width of about 13 μm manufactured by a conventional mechanical grinding method. It becomes possible.

In this etching step, for example, Ar, K
It is desirable to use an ion etching method using inert gas ions such as r, Xe, and He. According to the ion etching method, the metal magnetic thin film 27 can be etched in the thickness direction of the substrate 21 by maintaining the projection shape of the bridge-like portion 32b of the resist film 32 with high accuracy by an ion beam having excellent straightness. . That is, the etching can be performed with high precision so that the side wall 27a of the metal magnetic thin film 27 is substantially perpendicular to the thickness direction of the substrate 21.

At this time, the angle of incidence of the ion beam on the substrate 21 is desirably about 25 to 35 °. This makes it possible to make the re-attachment rate of burrs to the bridge portions 32b of the resist film 32 and the side wall portions 27a of the metal magnetic thin film 27 substantially equal to the etching rate at which the burrs themselves are etched. The shape of the side wall portion 27a of the metal magnetic thin film 27 does not collapse. For the same reason, the ion etching apparatus used in this etching step desirably has an ion beam traveling angle error of about 3% or less.

Next, as shown in FIG. 13, the non-magnetic material 33 is filled in the recess 30a of the low-melting glass 30. The recess 30a corresponds to the notch 19 in the magnetic head 1. Therefore, by filling the recess 30a with the non-magnetic material 33, it is possible to prevent the magnetic recording medium sliding on the sliding surface 9 from being damaged by the edge of the notch 19 as described above.

As the non-magnetic material 33, for example, A
Oxides such as l ₂ O ₃ , SiO ₂ , Ta ₂ O ₅ , Cr ₂ O ₃ and TiO ₂ , and metals such as Cr, Pr, Au and Ag can be used. The non-magnetic material 33 may be filled in the recess 30a by using various PVD methods such as a sputtering method and a plating method.

Next, the main surface of the low-melting glass 30 in which the recess 30a is filled with the non-magnetic material 33 is flattened by mirror polishing. Thereby, as shown in FIG. 13, the metal magnetic thin film 27 is narrowly exposed from the main surface of the low melting point glass 30. Note that the above-described recess 30a
Is very fine compared to the size of the entire substrate 21, so that the structure shown in FIG. 12 is omitted in the drawings shown below.

Next, as shown in FIG. 14, the low-melting glass 30 is etched to form the coil-forming recess 15 and the groove 18, and the thin-film coil is formed in the coil-forming recess 15. 6 is formed.

The concave portion 15 for forming the coil is formed on the rear butting surface 1.
2 as a substantially rectangular shape having a substantially center at the rear butting surface 12.
And by etching the portions other than the coil connection terminals 16. The coil forming recess 15 is provided with a groove 1 extending from one end to the terminal groove 31.
5a.

The groove 18 is formed in a direction perpendicular to the front butting surface 11 so as to cut out an end of the front butting surface 11 opposite to the sliding surface 9 of the magnetic recording medium. . When the pair of magnetic core halves 2 are separated into the magnetic head 1, the grooves 18 are formed so as to be substantially parallel to the sliding surface 9 and to face both side surfaces of the magnetic head 1.

It is desirable that the groove 18 be filled with a non-magnetic material. Thus, as described above, it is possible to prevent the magnetic recording medium from being damaged by the sharp edge formed when the depth B of the front gap 13 is worn. Further, as the non-magnetic material to be filled in the groove 18, a material similar to the above-described non-magnetic material 33 can be used.

In the present embodiment, the grooves 18 are formed in both of the pair of magnetic core halves 2 to be joined in a later step, but the groove 18 is formed in one of the pair of magnetic core halves 2. May be formed.

Next, as shown in FIG. 15, a side groove 34, which is a square groove, is formed so as to cross the front abutting surface facing the main surface of the substrate 21 in parallel. Thereafter, the magnetic core half blocks 35 are formed by cutting the substrate 21 in which the magnetic core halves 2 are formed in a plurality of parallel rows so as to be aligned in each row.

The side grooves 34 are formed by grinding, and have a depth of 50 μm and a width of 400 μm, for example. When the side grooves 34 are formed, the side grooves 3
A part of the front abutting surface 11 is exposed on the side surface 4. The side grooves 34 are formed so as to expose the upper end of the front butting surface 11 as a positioning index when the pair of magnetic core half blocks 35 are butted, as described later.

After the formation of the side grooves 34, the main surface of the substrate 21 is flattened by mirror polishing. At this time, the front butting surface 11 and the rear butting surface 12 covered with the protective film are exposed to the outside.

Next, as shown in FIG. 16, a pair of magnetic core half blocks 35 is accurately positioned to perform metal diffusion bonding. At this time, the pair of magnetic core half blocks 35
Performs patterning of Au on the joint, and forms the side grooves 34.
The upper ends of the front butting surfaces 11 facing each other are opposed to each other so that accurate positioning is achieved. Then, metal diffusion bonding is performed by applying a predetermined temperature and pressure to the pair of butted magnetic core half blocks 35,
The magnetic head block 36 is manufactured.

In this embodiment, the metal diffusion bonding is performed by patterning Au. However, for example, a pair of magnetic core half blocks 35 is formed by using an adhesive or water glass.
They may be joined together.

Next, as shown in FIG. 17, the magnetic head block 36 is cut and separated into individual magnetic heads 1.

At this time, first, the magnetic head block 36
Is cut in the longitudinal direction with reference to the groove 18 as a depth marker in order to expose the surface serving as the sliding surface 9 on which the magnetic recording medium slides. Then, by performing cylindrical cutting so that the exposed surface has a cylindrical shape,
This surface becomes the sliding surface. Thereafter, the contact width regulating groove 10 is ground on the magnetic head block 36. The contact width regulating grooves 10 are formed at portions corresponding to both side surfaces of the sliding surface 9 of each magnetic head 1 separated from the magnetic head 36.

Then, the magnetic head block 36 is
7 are separated into individual magnetic heads 1 by cutting at a portion indicated by a DD line. Thus, the magnetic head 1 is completed.

As described above, according to the magnetic head manufacturing method of the present invention, the width of the magnetic gap in the track width direction can be formed with high precision by the resist process and the etching process. In addition, since the resist process and the etching process are thin film forming technologies, even when a large number of magnetic heads are formed on a substrate, these magnetic heads can be processed at once, thereby improving production efficiency. can do.

As described above, when joining the pair of magnetic core half blocks 35, the front butting surfaces 11 of the metal magnetic thin films 27 formed on the respective magnetic core half blocks 35 are substantially the same. It is desirable to set the width and to perform the alignment with high precision before joining. Thereby, it is possible to manufacture the magnetic head 1 having excellent recording / reproducing characteristics corresponding to the increase in recording density. However, in this case, the accuracy of the track width Tw of the magnetic head 1 depends on the accuracy of the alignment of the pair of magnetic core half blocks 35. In other words, if any deviation occurs at the joining position, the track width Tw decreases.

Therefore, when joining the pair of magnetic core half blocks 35, the front butting surfaces 11 of the metal magnetic thin films 27 formed on the respective magnetic core half blocks 35 have slightly different widths. It may be formed. In the magnetic head 1, the narrower front butting surface 11 is formed.
Becomes the effective track width Tw.
By forming ones with slightly different widths, alignment can be facilitated and a desired track width Tw can be reliably obtained. When joining the pair of magnetic core half blocks 35, the joining accuracy is 1 μm.
It is desirable that the difference between the widths of the front butting surfaces 11 be 1 to 2 μm, since it is easy if the distance is about m.

In the above-described etching step, both side edges of the metal magnetic thin film 27 are cut off. However, the metal magnetic thin film 2 exposed together with the substrate 21 from the low melting glass 30 is formed.
7 may be cut out only on the side edge on the substrate 21 side or on the side edge opposite to the substrate 21. In addition, in the etching step, generally, the resist film 32 is also etched little by little. Therefore, the width of the front abutting surface 11 of the metal magnetic thin film 27 in the track width Tw direction and the front abutting surface 11
Side wall 27a cut out substantially perpendicular to the direction of the substrate 21
There is a trade-off between the height and the height. Therefore, in order to obtain a desired width and height, the resist film 32
It is desirable to adjust the width and height of the bridge-like portion 32b, and to appropriately select a resist material used for the resist film 32.

Further, the side wall 27a of the metal magnetic thin film 27 formed by the etching step is gradually reduced in height in the subsequent flattening step and the like. Therefore, in this etching step, the height of side wall portion 27a is 5 μm
It is desirable that the metal magnetic thin film 27 be cut out as described above.

[0095]

As described above, in the magnetic head according to the present invention, at least one of the metal magnetic thin films formed on each of the pair of magnetic core halves has:
It is formed by cutting out in the track width direction at the abutting surface. Thereby, the width of the magnetic gap in the track width direction is formed. Therefore, the magnetic head according to the present invention can accurately record and reproduce fine magnetic signals in response to the increase in recording density.

Further, according to the method of manufacturing a magnetic head of the present invention, the width of the magnetic gap in the track width direction can be narrowed with high precision by the resist forming step and the etching step, which are thin film forming techniques. Thus, for example, a large number of magnetic heads formed on a substrate material can be processed at once, and a large number of magnetic heads can be processed in a short time. Therefore, it is possible to efficiently produce a magnetic head capable of accurately recording and reproducing a fine magnetic signal corresponding to a higher recording density.

[Brief description of the drawings]

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

FIG. 2 is an enlarged perspective view of a main part showing a magnetic core of the magnetic head and its vicinity.

FIG. 3 is an enlarged side view of a main part showing a depth of the magnetic head.

FIG. 4 is an enlarged plan view of a main part showing a magnetic gap of the magnetic head.

FIG. 5 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. 6 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state where a magnetic core forming groove is formed on the substrate.

FIG. 7 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state where a metal magnetic thin film is formed.

FIG. 8 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state where the separation groove and the winding groove are formed.

FIG. 9 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state where low-melting glass is filled.

FIG. 10 is a diagram for explaining the method for manufacturing the same magnetic head, and is a perspective view showing a state where a terminal groove is formed on the substrate.

11A and 11B are views for explaining a method of manufacturing the magnetic head, wherein FIG. 11A is a plan view showing a state in which a resist film is formed, and FIG. 11B is a cross-sectional view.

FIG. 12 is a view for explaining the method for manufacturing the magnetic head, and is a cross-sectional view showing a state where the metal magnetic thin film is etched.

FIG. 13 is a view for explaining the method for manufacturing the same magnetic head, and is a cross-sectional view showing a state in which a concave portion formed by etching is filled with a non-magnetic material.

FIG. 14 is a diagram for explaining the method for manufacturing the same magnetic head, and is a perspective view showing a state where a thin-film coil is formed.

FIG. 15 is a diagram for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state where the substrate is cut and separated into magnetic core half blocks.

FIG. 16 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing a state in which a pair of magnetic core half blocks is being joined.

FIG. 17 is a view for explaining the method for manufacturing the magnetic head, and is a perspective view showing the magnetic head block.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 magnetic head, 2 magnetic core halves, 3 substrate, 4 metal magnetic thin film, 5 low melting point glass, 7 non-magnetic thin film, 19
Notch

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuka Kadoma 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Koji Suzuki 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 5D093 AA01 BB04 BB05 BB18 BD01 BD08 EA02 FA18 FA26 HA16 HA18 JA01 5D111 AA19 AA22 BB12 BB18 BB37 BB48 FF04 GG16 HH16 JJ07 JJ08 KK01

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 having a magnetic gap formed by abutting the front butting surfaces of the metal magnetic thin films so as to face each other via a nonmagnetic thin film, wherein at least one of the metal magnetic thin films is A magnetic head characterized in that at least one side of both sides in the track width direction exposed on the surface is cut out downward from the abutting surface. 2. A pair of magnetic core halves having a metal magnetic thin film formed obliquely on a substrate, forming a thin film coil, and flattening an abutting surface with a nonmagnetic material. A method of manufacturing a magnetic head in which a magnetic gap is formed by abutting butting surfaces so as to face each other via a non-magnetic thin film, wherein at least one of the pair of magnetic core halves is exposed to the abutting surface. A resist forming step of forming a resist film narrower than the metal magnetic thin film on the metal magnetic thin film, and an etching step of performing an etching process on the metal magnetic thin film with the width of the resist film. A method of manufacturing a magnetic head, characterized in that the metal magnetic thin film is formed narrow in the track width direction on the abutting surface. 3. The method of manufacturing a magnetic head according to claim 2, wherein in the etching step, an etching process is performed using an ion etching method. 4. The method of manufacturing a magnetic head according to claim 3, wherein, in the etching step, an incident angle of the ion beam is set to 25 ° or more and 35 ° or less.