JP2996826B2 - Method of manufacturing magnetic head and magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head provided in a magnetic recording / reproducing apparatus such as a video tape recorder and comprising a soft magnetic thin film constituting a magnetic circuit, and a substrate for supporting the soft magnetic thin film. The present invention relates to a method for manufacturing a magnetic head.

[0002]

2. Description of the Related Art With the advancement of magnetic recording technology, high coercivity media such as metal tapes have become mainstream.
The core material used for the magnetic head is required to have a high saturation magnetic flux density and a narrow track. Under such circumstances, conventionally, a magnetic head using a head chip 40 as shown in FIG. 10 has been proposed.

The manufacturing process of the head chip 40 will be described. First, as shown in FIG. 11, for example, a non-magnetic material such as photosensitive crystallized glass and crystallized glass and an oxide magnetic material such as soft magnetic ferrite are used. A substantially V-shaped thin film forming groove 31 having a predetermined pitch C is formed on the surface of the substrate 30, and a soft magnetic thin film 35 having a predetermined thickness is formed on the wall surface of the thin film forming groove 31. I do. Next, the thin film forming groove 3 is formed.
1 are filled with the low melting point glass 32, and as shown in FIG.
The low-melting glass 32 is polished in a plane until the upper end surfaces of the two coincide.

[0004] Thereafter, as shown in FIG. 13, the soft magnetic thin film 3 on the sliding surface of the recording medium (the surface on the near side in the figure).
5 so that the film thickness dimension becomes a predetermined track width dimension.
Along with the soft magnetic thin films 35, the substrate 30 and the low-melting glass 32 adjacent to the soft magnetic thin films 35 are ground to perform a track width regulating process. Accordingly, the track width regulating grooves 41 having a predetermined depth are formed on the sliding surface.
Are formed adjacent to the soft magnetic thin films 35. Next, an internal winding groove 37 and an external winding groove 38 are formed on both side surfaces of the substrate 31, and a gap made of a non-magnetic gap material (not shown) is formed on the gap surface 33, which is a polished surface of the low melting glass 32. By forming, the substrate block 34 is manufactured.

[0005] Then, as shown in FIG. 14, the gap surfaces 33 of the pair of substrate blocks 34 are opposed to each other, fixed by pressing, and joined to form a core block 39.
To form Further, by molding a low-melting glass 36 for a sliding surface having a lower melting point than the low-melting glass 32 on the sliding surface of the core block 39, the previously formed track width regulating grooves 41 are filled. .

After this step, as shown in FIG. 15, the low-melting-point glass 36 for a sliding surface is polished into a flat shape.
By cutting the core block 39 along a two-dot chain line at a predetermined pitch dimension D, individual head chips 40 as shown in FIG. 10 are manufactured.

[0007]

However, in the above-described manufacturing method and the magnetic head having the above-described structure, there is a problem that the quality of the magnetic head is deteriorated due to the following causes.

That is, in the above-described manufacturing method, the track width regulating processing is performed in the state of the individual substrate blocks 34, and then, the pair of substrate blocks 34, 34 are pressure-bonded to form the core block 39. At the time of joining by pressure bonding, when the pitch of the above substantially V-shaped groove 31 shifts, or when the parallelism shifts during the track width regulation processing in the substrate block 34, the completed head chip 40
The tracks formed by the soft magnetic thin films 35 may be shifted. When information is recorded on a recording medium using the magnetic head constituted by the head chips 40 whose tracks are shifted as described above, the quality of the magnetic head deteriorates, such as side erasure caused by a leakage magnetic field. .

In the magnetic head in which the track width regulating groove is filled with the low melting point glass, the low melting point glass is liable to be clouded, so that the recording head is liable to be deteriorated by running for a long time, and the recording is performed. Discharge noise is also likely to occur due to frictional charging with the medium, which leads to deterioration in quality.

[0010]

According to a first aspect of the present invention, there is provided a method of manufacturing a magnetic head, comprising:
A soft magnetic thin film forming a magnetic circuit is formed, and a pair of substrates having a low melting point glass provided on the soft magnetic thin film is joined to the magnetic head sliding surface so that the soft magnetic thin film is continuous. In the method of manufacturing a head, after bonding the pair of substrates, both sides of the soft magnetic thin film are ground so that the thickness of the soft magnetic thin film on the sliding surface has a predetermined track width dimension. Processing, and the nonmagnetic ceramic
It is characterized by being filled with a mixture of powder adhesive and powdered ceramics .

According to a second aspect of the present invention, there is provided a magnetic head in which a soft magnetic thin film forming a magnetic circuit is formed, and a low melting point glass is provided on the soft magnetic thin film. and the magnetic head provided with a substrate, to the soft magnetic thin film track width regulating grooves formed adjacent to the film thickness of the soft magnetic thin film is restricted to a predetermined track width of the magnetic head sliding face, non Ceramic adhesives that are magnetic
And a ceramic material composed of a mixture of powder and ceramics .

[0012]

According to the first aspect of the present invention, even when the soft magnetic thin films are bonded with a slight deviation during the bonding of the substrates, the thickness of the soft magnetic thin films is controlled by the track width regulating processing performed after the bonding of the substrates. And the track deviation is corrected. Therefore, in the completed magnetic head, track deviation does not occur and side erasure due to a leakage magnetic field is avoided, so that the quality of the magnetic head is improved and the thickness of the soft magnetic thin film is reduced. As regulations are relaxed, yields are also improved. Moreover, in the above method,
Non-magnetic ceramic
Filled with a mixture of mix adhesive and powdered ceramics
So a mixture of ceramics adhesive and powdered ceramics
The ceramic material consisting of
As is clear from FIG.
Compared to low melting glass that has been
Since the frictional resistance with the recording medium is small,
Even in the case, it does not cause cloudiness and prevents running deterioration
As well as frictional electrification when the recording medium slides.
Suppresses discharge noise caused by frictional charging
Therefore, a magnetic head with improved quality can be manufactured.

According to the second aspect of the present invention, the ceramic material is embedded in the track width regulating groove provided adjacent to the soft magnetic thin film. As is clear from the experimental results described in the examples,
Compared to the low-melting glass filled in the above grooves, because it has excellent slidability and low frictional resistance with the recording medium,
Even when used for a long time, no turbidity occurs, running deterioration can be prevented, and there is no frictional charging at the time of sliding of the recording medium, and discharge noise caused by this frictional charging can be suppressed. The quality of the magnetic head is improved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

The magnetic head manufactured by the manufacturing method of this embodiment includes a head chip 1 having a high saturation magnetic flux density as shown in FIG. This head chip 1
Has a pair of substrates 11 made of a non-magnetic material such as photosensitive crystallized glass or crystallized glass or an oxide magnetic material such as soft magnetic ferrite. This substrate 11
・ 11 is a head chip 1 serving as a sliding surface with a recording medium.
The soft magnetic thin films 13 are formed on the upper end surface thereof so that the film thickness is regulated so as to have a predetermined track width dimension, and the first low melting point glass 12 is formed on the soft magnetic thin films 13.
2 are filled. The soft magnetic thin films 13
The second low melting point glass (track width regulating member) 2 having a melting point lower than that of the first low melting point glass 12 is provided in the track width regulating grooves 27 provided on both sides of the first low melting point glass 12.
6 is molded.

The manufacturing process of the head chip 1 having the above configuration will be described. First, as shown in FIG. 3, the surface of the rectangular substrate 11 made of the above-mentioned non-magnetic material or oxide magnetic material is By dicing using a rotary blade or the like, a substantially V having a predetermined depth and a pitch dimension A is obtained.
A plurality of thin film forming grooves 20 in the shape of a letter are formed adjacent to each other and extend in parallel with each other. Then, as shown in FIG. 4, a soft magnetic layer made of, for example, an Fe—Al—Si alloy having a predetermined thickness is formed on one inclined surface of the thin film forming grooves 20 by, for example, vacuum evaporation or sputtering. Thin film 1
3 are formed.

Next, as shown in FIG. 5, the above-mentioned thin film forming grooves 20 are filled with a first low melting point glass 12, and as shown in FIG. The first low-melting glass 12 is polished into a plane until the tops of the thin film forming grooves 20 coincide with each other. At the same time, the first low-melting glass 12 protruding from the side surface of the substrate 11 serving as a sliding surface with the recording medium is also polished and removed.

Thereafter, as shown in FIG. 7, an internal winding groove 21 and an external winding groove 22 are formed on both side surfaces of the substrate 11, and a gap, which is a polished surface of the first low melting glass 12, is formed. A nonmagnetic gap material (not shown) made of SiO ₂ or the like is vacuum-deposited so that a predetermined gap is formed on the surface 23.
Alternatively, the substrate block 24 is formed by sputtering or the like.

Next, as shown in FIG. 8, the gap surfaces 23 of the pair of substrate blocks 24 are opposed to each other, and the soft magnetic thin films 13 are aligned so as to be substantially in a straight line. By pressing and fixing, the pair of substrate blocks 24 are joined to form the core block 25.

After this step, as shown in FIG. 1, a track width regulating process is performed by, for example, dicing. That is, by grinding both sides of the soft magnetic thin films 13 exposed on the sliding surface of the core block 25 and the first low melting point glass 12 and the substrate 11 adjacent to the soft magnetic thin films 13, a predetermined shape is obtained. To form a plurality of track width regulating grooves 27 located in parallel with each other, and regulate the film thickness of the soft magnetic thin films 13 on the sliding surface to a predetermined track width dimension. Subsequently, as shown in FIG.
Are molded with a second low-melting glass 26 having a lower melting point than the first low-melting glass 12.

Then, the second low-melting glass 26 is polished in a plane until the soft magnetic thin film 13 on the sliding surface of the core block 25 is exposed on the surface. Along the two-dot chain line in FIG.
Are cut to produce individual head chips 1 as shown in FIG. Further, after the head chip 1 is bonded and fixed to a base plate (not shown), the coil winding and the sliding surface are polished to complete the magnetic head.

As described above, in the present embodiment, when the pair of substrate blocks 24, 24 are joined,
When the base blocks 24 are joined to form the core block 25, the track width regulating grooves 2 are formed on both sides of the soft magnetic thin films 13 even when the base blocks 3 and 13 are joined with a slight shift.
7 are formed, and the track width regulation processing is performed on the soft magnetic thin films 13 exposed on the sliding surface, so that no track shift occurs in the completed head chip 1. Therefore, at the time of recording, the risk of side erasure due to the leakage magnetic field is avoided, the quality of the magnetic head can be improved, and the thickness of the soft magnetic thin film 13 in the manufacturing process of the magnetic head can be reduced. The yield can be improved because the regulations can be roughened.

In the above embodiment, the second low melting point glass having a lower melting point than the first low melting point glass is used as the track width regulating member. However, the present invention is not limited to this. In the method of manufacturing a magnetic head according to the present invention, an epoxy resin, an ultraviolet curable resin, or the like can be applied as the track width regulating member as long as there is no problem in slidability with a recording medium.

[0024] In addition, as described in claim 2, the second
In place of the low melting point glass, in the track width regulating groove, as a ceramic material, for example, a ceramic adhesive such as Alon ceramic (c) manufactured by Toa Gosei Chemical Industry Co., Ltd., and to increase the ceramic concentration in the adhesive, It is also possible to manufacture a magnetic head by filling a mixture of powdered ceramics. Since such a ceramics adhesive is non-magnetic, there is almost no sliding noise due to sliding with the recording medium, similarly to the low melting point glass.

The magnetic head in which the track width regulating groove is filled with the above-mentioned ceramic material and the magnetic head in which crystallized glass or low-melting glass is filled are slid for several hours, and before and after sliding. When observing the state of the moving surface, the crystallized glass or low-melting glass shows cloudiness and running degradation (reduced output) occurs.
Almost no turbidity is observed in the ceramic material, and running deterioration does not occur even after long-term use.

Further, with respect to the above two magnetic heads,
In order to compare the triboelectric charging caused by the sliding, the charging of each filling material was measured by a surface potentiometer. Assuming that the charging of the crystallized glass was 100%, the low melting glass was about 45%, and the ceramic material was 0.1. %. When the above-mentioned numerical value is about 55% or more, discharge noise is generated. Therefore, it can be understood that the use of the ceramic material as a filling material suppresses the discharge noise caused by frictional charging. Therefore, the quality of the magnetic head can be improved by using the above-mentioned ceramic material.

[0027]

According to the method of manufacturing a magnetic head according to the first aspect of the present invention, after bonding the pair of substrates,
In order that the thickness of the soft magnetic thin film on the sliding surface becomes a predetermined track width dimension, grinding is performed on both sides of the soft magnetic thin film to perform a track width regulating process. Non-magnetic ceramic adhesive and powder
It is for filling a mixture of ceramics .

Therefore, there is no track deviation in the manufactured magnetic head, and side erase due to a leakage magnetic field can be prevented, so that the effect of improving the quality of the magnetic head can be obtained.

Further, since the regulation of the film thickness at the time of forming the soft magnetic thin film on the substrate or the like can be relaxed, the effect of improving the yield can be obtained. Besides, it is non-magnetic
Filled with a mixture of ceramics adhesive and powdered ceramics
It has excellent slidability and prevents running deterioration.
As well as frictional electrification when the recording medium slides.
Suppresses discharge noise caused by frictional charging
Can produce a magnetic head with improved quality.
This effect is also achieved.

In the magnetic head according to the second aspect of the present invention, as described above, the thickness of the soft magnetic thin film on the sliding surface of the magnetic head is restricted to a predetermined track width so as to be adjacent to the soft magnetic thin film. In this configuration, a ceramic material having a lower melting point than that of the low-melting glass is buried in the formed track width regulating groove.

Therefore, when the above-mentioned ceramic material is used as a material to be filled in the track width regulating groove, cloudiness due to sliding of the recording medium and frictional electrification are lower than when low melting glass is used. As a result, the generation of discharge noise and the like due to the above is suppressed, so that the quality of the magnetic head is improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a core block in which a track width regulating groove is formed in a method of manufacturing a magnetic head according to an embodiment of the present invention.

FIG. 2 is a perspective view of a head chip cut out from the core block.

FIG. 3 is a front view of a substrate on which a thin film forming groove is formed in a process of manufacturing the magnetic head.

FIG. 4 is a front view of a substrate having a soft magnetic thin film formed on an inclined surface of the thin film forming groove.

FIG. 5 is a front view of the substrate in which the thin film forming groove is filled with a first low-melting glass.

FIG. 6 is a front view of the substrate on which the first low-melting glass is polished in a planar shape.

FIG. 7 is a perspective view of a substrate block manufactured from the substrate.

FIG. 8 is a perspective view of a core block formed by joining the substrate blocks.

FIG. 9 is a perspective view of a core block in which the track width regulating groove is filled with a second low melting point glass.

FIG. 10 is a perspective view of a head chip manufactured by a conventional manufacturing method.

FIG. 11 is a front view of a substrate in which a groove for forming a thin film and a soft magnetic thin film are formed in a conventional magnetic head manufacturing process, and further filled with low-melting glass.

FIG. 12 is a front view of a substrate on which the low-melting glass is polished in a plane.

FIG. 13 is a perspective view of a substrate block obtained by subjecting a soft magnetic thin film provided on the substrate to a track width regulating process.

FIG. 14 is a perspective view of a core block in which the substrate blocks are joined and filled with a low-melting glass for a sliding surface.

FIG. 15 is a perspective view of a core block in which the low-melting-point glass for a sliding surface is polished into a flat shape.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 head chip 11 substrate 12 first low melting point glass 13 soft magnetic thin film 26 second low melting point glass (track width regulating member) 27 track width regulating groove

Claims (2)

(57) [Claims] A soft magnetic thin film forming a magnetic circuit is formed, and a pair of substrates having a low melting point glass provided on the soft magnetic thin film is connected to the soft magnetic thin film on a sliding surface of a magnetic head. In the method for manufacturing a magnetic head to be joined as described above, after joining the pair of substrates, the thickness of the soft magnetic thin film on the sliding surface has a predetermined track width dimension.
Perform track width regulating process by grinding both sides of the soft magnetic thin film, the groove produced by the track width control processing, the non-magnetic
A method for manufacturing a magnetic head, characterized by filling a mixture of a ceramic adhesive and powdered ceramics . 2. A magnetic head comprising a substrate on which a soft magnetic thin film for forming a magnetic circuit is formed and a low melting point glass provided on the soft magnetic thin film. In order to regulate the film thickness to a predetermined track width dimension, a non-magnetic ceramic contact is formed in a track width regulating groove formed adjacent to the soft magnetic thin film.
A magnetic head comprising a ceramic material comprising a mixture of an adhesive and powdered ceramics embedded therein.