JPH06267024A - Manufacture of azimuth thin film magnetic head - Google Patents

Abstract

PURPOSE:To obtain a smaller inexpensive azimuth thin film magnetic head by forming a center core part and a side core part once while a coil is made up of a thin film. CONSTITUTION:In the manufacture of an azimuth thin film magnetic head, a connection core 10, a thin film coil 11 and a side core 6 are formed on a first non-magnetic substrate 5 sequentially sandwiching an inorganic insulation film 12 separately. Moreover, after the formation of a protective film, a core is cut inclined by a specified azimuth angle with respect to the first non- magnetic substrate 5, a cut surface is ground to form a gap and then, two cut pieces are bonded. Here, it is preferable that the thickness of the connection core 10 is larger than that of the side core 6. The coil 11 is made up of a thin film. This makes possible the obtaining of a smaller inexpensive magnetic head less affected by an external magnetic noise or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an azimuth thin film magnetic head used in a VTR or the like.

[0002]

2. Description of the Related Art Heretofore, magnetic heads which have been mechanically processed, for example, or MIG (metal-in-gap) heads in which a metal magnetic material is formed near the gap have been the mainstream of magnetic heads. However, in response to the recent demand for higher density, a thin film magnetic head having excellent high frequency characteristics has been developed. A conventional thin film magnetic head uses a permalloy plating film as a core material. However, in order to further improve the head characteristics, materials having better magnetic characteristics than the permalloy plated film, such as Co-based amorphous magnetic material and sendust, have been used as the core material.

By the way, a home VTR uses an azimuth recording method in which the magnetization directions are made different between adjacent recording tracks. In addition, the azimuth angles are different from each other so that still reproduction can be performed even if adjacent tracks are reproduced and scanned.
A magnetic head is provided in which two head gaps are arranged close to each other in the longitudinal direction of the recording track. This magnetic head is called a double azimuth magnetic head.

3 and 4 are perspective views of a conventional double azimuth thin film magnetic head.

The conventional example shown in FIG. 3 is a double azimuth magnetic head in which two ferrite heads 21a and 21b having different azimuth angles are attached to the same head mount 23.

In this case, there is a problem that it is necessary to attach the magnetic heads with high accuracy such as the positional relationship between the two magnetic heads and the protruding step of the tape sliding surface portion.

On the other hand, in the conventional example shown in FIG. 4, a magnetic layer 61 separated into two by a predetermined space 8 is formed on the non-magnetic substrate 5, and the low magnetic layer 61 is formed on each of the magnetic layers 61. The non-magnetic layer 9 is adhered using a melting point glass as an adhesive. Both side surfaces of the center core portion 2 and predetermined side surfaces 7 of the side core portion 1 are cut and polished at a predetermined inclination angle corresponding to the azimuth angle, and after the winding holes 4 are formed in the side core portion 1, a predetermined gap is formed. The center core portion 2 and the side core portion 1 are bonded so that the length is formed.

In this case, since the center core portion and the two side core portions, which are integrally manufactured, are cut and then rejoined, the relative positions of the two head gaps are accurately formed. Can be easily and highly accurately mounted on the mounting base.

However, since the thin film is not used for the coil, the area of the core must be made large, and it is easily affected by external magnetic noise, and the head reproduction output per unit inductance becomes low. Not taking advantage of the head.

Further, winding is required for each head chip, which requires time. Also, since the core film thickness is uniform, when the track width is narrow, that is,
When the film thickness of the core becomes thin, it is very difficult to align the two positions of the sliding surface and the rear when bonding.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a highly accurate and inexpensive method for manufacturing azimuth and double azimuth thin film heads, excluding the drawbacks of the prior art.

[0012]

That is, according to the method of manufacturing an azimuth thin film magnetic head of the present invention, a connection core, a thin film coil and a side core are sequentially formed on a first non-magnetic substrate with an inorganic insulating film interposed therebetween. After further forming a protective film, the core is cut at a predetermined azimuth angle with respect to the first non-magnetic substrate, the cut surface is polished to form a gap, and then both cut pieces are bonded. It is characterized by doing.

In the method for manufacturing an azimuth thin film magnetic head of the present invention, it is preferable that the connecting core is formed thicker than the side core.

In the method for manufacturing an azimuth thin film magnetic head of the present invention, after forming the protective film, a second non-magnetic substrate is further adhered on the protective film, and a predetermined non-magnetic substrate is attached to the first non-magnetic substrate. It is preferable that the core is cut by inclining it by an azimuth angle, the cut surface is polished to form a gap, and then both cut pieces are bonded.

According to the method of manufacturing the double azimuth thin film magnetic head of the present invention, two sets of the connecting core, the thin film coil and the side core are arranged at symmetrical positions on the first non-magnetic substrate at a predetermined interval in the track scanning direction. An inorganic insulating film is sandwiched between layers to form a protective film, and then a protective film is formed. Then, each core is cut by inclining a predetermined azimuth angle different from the first non-magnetic substrate, and the cut surface is polished. After forming the gap, the cut pieces are bonded.

In the method for manufacturing a double azimuth thin film magnetic head of the present invention, it is preferable that the thickness of the connection core is made thicker than the thickness of the side core.

In the method for manufacturing a double azimuth thin film magnetic head of the present invention, after forming the protective film, a second non-magnetic substrate is further adhered onto the protective film, and a predetermined different one is attached to the first non-magnetic substrate. It is preferable that the cores are cut by inclining them by an azimuth angle, the cut surfaces are polished to form gaps, and then the cut pieces are bonded.

[0018]

In the thin film magnetic head according to the present invention, the center core portion and the side core portion are formed at the same time, so the process is simple. At the same time, by using a thin film coil, the inductance value of the core can be lowered, and the reproduction per inductance can be reduced. The output is increased and the S / N ratio can be increased.

Further, by making the thickness of the connecting core thicker than the thickness of the side core, it is possible to easily and accurately join them at the time of re-adhesion after cutting.

[0020]

EXAMPLE A method for manufacturing an azimuth and double azimuth thin film magnetic head of the present invention is a method in which a center core portion and a side core portion are integrally manufactured at the same time, cut, and a magnetic gap portion is formed and then joined again. The use of thin film coils reduces the area of the core resulting in an azimuth thin film magnetic head with a large read output per inductance. Further, by making the rear connecting core thicker than the side core, it becomes easy to align the sliding surface and the connecting core during bonding.

FIG. 1 is a plan view of an element in which a center core portion and a side core portion are integrated at a previous stage of forming a double azimuth thin film magnetic head obtained by the method of the present invention. In FIG. 1, 1 is a side core part and 2 is a center core part. An inorganic insulating film 121 is provided on a first non-magnetic substrate (not shown because it cannot be seen under the insulating film 121 in FIG. 1), and the connection core 10 is provided on the insulating film 121 by sputtering. It is preferable that the connecting core 10 is thicker than the side core 6 by several μm because the operation when cutting and reconnecting the core later becomes easy. After providing the shunt core 15 at both ends of the connection core 10, and further providing an inorganic insulating film (not shown) around it,
A coil 11 made of a magnetic thin film is formed around a shunt core 15. The coil 11 is connected to the outside by a lead wire 16.

After that, an inorganic insulating film is provided again (not shown), and a U-shaped core made of a magnetic thin film having a film thickness equal to the track width is formed on the inorganic insulating film. The core is to become the side core 6 after the head is formed.

In the case of the azimuth thin film magnetic head,
One connecting core, one shunt core, one coil, and one side core are formed on the insulating film on the non-magnetic substrate of Fig. 1 when manufacturing a double azimuth thin film magnetic head.
As shown in, the two sets are arranged in the longitudinal direction of the track at a predetermined interval 8.

An inorganic insulating film is formed between the connection core, the coil and the side core of the element formed as described above, and finally, the inorganic insulating film is provided as a protective layer so as to have a uniform thickness over the entire surface. A second non-magnetic substrate may be provided on the upper surface of the protective layer if necessary.

In order to obtain the magnetic head, the element is used as shown in FIG.
It can be obtained by cutting at the azimuth angle defined with respect to the first non-magnetic substrate at the broken line portion of 7 and polishing the portion including the side core of the cut surface after polishing and then rejoining.

According to the method of the present invention, even in the case of a double azimuth thin film magnetic head, the core, the coil, etc. are integrally formed,
Since it is cut and rejoined, it is possible to easily obtain extremely excellent gap positional accuracy. Further, by making the connecting core thicker than the side core, it becomes easy to align the two positions of the connection of the sliding surface and the rear when rejoining after cutting.

Next, the present invention will be described in more detail with reference to FIGS. 2 (a) to 2 (h). Since the manufacturing method is almost the same in the case of the azimuth thin film magnetic head and the case of the double azimuth thin film magnetic head, the manufacturing method of the double azimuth thin film magnetic head will be described below.

[Embodiment 1] FIGS. 2 (a) to 2 (h) are cross-sectional views taken along the line AA in FIG. 1 for explaining each step of an embodiment of a method of manufacturing a double azimuth thin film magnetic head of the present invention. Is.

First, on the first non-magnetic substrate 5, Al ₂ O ₃ ,
An inorganic insulating film 121 such as SiO _{2 is} formed by sputtering, a magnetic film to serve as a connection core is formed thereon to be thicker than a side core to be formed later, and then the magnetic film is annealed and etched. The connection core 10 was formed into a predetermined shape (FIG. 2A).

After that, an insulating film 122 of Al ₂ O ₃ , SiO ₂ or the like was formed again on the entire surface, and flat polishing was performed up to the core surface (FIG. 2B). The insulating film 122 has the same composition as the insulating film 121, and the overlapping portions are integrated, and the insulating films to be formed below are also integrated with the overlapping portions.

Next, the shunt core 15 is placed on the connection core 10.
(FIG. 2C), and then the insulating film 123 was formed. Since the coil is formed on the insulating film, the insulating film must be thinner than the shunt core 15 (FIG. 2 (d)).

After that, a spiral thin film coil is formed on the insulating film 123 by a photolithography process and a plating method.
11 was formed, and then the coil lead-out portion 14 was subjected to thickening plating (FIG. 2 (e)).

Next, an insulating film 124 was formed, and the surfaces of the shunt core 15 and the coil lead-out portion 14 were flatly polished (FIG. 2 (f)).

Next, a magnetic film to be the side core 6 is formed by sputtering, and after annealing the magnetic film, the magnetic film is etched into a predetermined shape to form the coil lead wire 16 and the external connection terminal portion 17. Formed (Fig. 2
(G)).

Each layer from the formation of the connection core 10 to the external connection terminal portion 17 of the coil lead wire was formed in two sets at predetermined intervals 8 in the longitudinal direction of the track as shown in FIG.

Next, an insulating film 125 serving as a protective film was formed, and flat polishing was performed until the connection terminal portion 17 of the coil lead wire 16 was exposed (FIG. 2 (h)).

A first non-magnetic substrate was adhered on the insulating film 125 to obtain a device before head formation.

The element obtained as described above is inclined at different azimuth angles with respect to the non-magnetic substrate for each core, cut at the position shown by the broken line 7 in FIG. 1, and the gap surface of the side core is polished. After that, gap materials were formed and then joined again. At the time of joining, since the connecting core was formed thicker than the side core, it was easy to position the connecting core portion. After that, it was shaped into a chip shape to form a double azimuth head.

[Embodiment 2] In Embodiment 1, the first non-magnetic substrate is adhered on the protective film. However, in this embodiment, the adhesion of the insulating substrate is omitted, and the other steps are the same as those in Embodiment 1. I went the same way.

In this way, a mold having no second non-magnetic substrate on the top was obtained.

The second non-magnetic substrate provided on the protective film is intended to prevent the abrasion of the protective film during sliding, and when abrasion does not occur depending on the material of the protective film, As described above, the protective film may be thickened to omit the second non-magnetic substrate.

In the first and second embodiments, the coil is formed by spiral winding, but it can be obtained in the same manner in the case of helical winding.

In the first and second embodiments, the connecting core is used.
Two sets of each layer from the formation of 10 to the external connection terminal part 17 of the coil lead wire were formed. The element obtained by forming only one set of these was tilted by a predetermined azimuth angle with respect to the non-magnetic substrate. Then, the azimuth thin film magnetic head is obtained by cutting at the position of the broken line 7 in FIG. 1, polishing the gap surface of the side core, forming a gap material, and connecting both the pieces.

[0044]

As described above, according to the method of the present invention, the center core portion and the side core portion are formed at the same time, and the coil is formed of a thin film, so that the process is simplified and the size is reduced. It is possible to obtain an inexpensive azimuth thin film magnetic head. As a result, it is less susceptible to external magnetic noise, and the core inductance value can be lowered.
Reproduction output per unit inductance becomes large and S / N
The ratio can be increased and a high performance azimuth thin film magnetic head can be obtained.

Further, by forming the thickness of the connecting core to be thicker than the thickness of the side core, the positioning at the time of joining can be easily and accurately performed.

[Brief description of drawings]

FIG. 1 is a plan view of an element of a double azimuth thin film magnetic head obtained by the method of the present invention before gap formation.

FIG. 2 is an explanatory cross-sectional view of an essential part of a step for explaining the method of the present invention.

FIG. 3 is a perspective view of a conventional thin film magnetic head.

FIG. 4 is a perspective view of a conventional thin film magnetic head.

[Explanation of symbols]

 5 First non-magnetic substrate 6 Side core 10 Connection core 11 Thin film coil 12 Inorganic insulating film 125 Protective film

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[Procedure amendment]

[Submission date] June 14, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (6)

[Claims] 1. A connection core, a thin film coil and a side core are sequentially formed on a first non-magnetic substrate with an inorganic insulating film sandwiched therebetween, and a protective film is further formed on the first non-magnetic substrate. On the other hand, a method for manufacturing an azimuth thin film magnetic head, which comprises inclining a core with a predetermined azimuth angle, polishing the cut surface to form a gap, and then adhering both cut pieces. 2. The method of manufacturing an azimuth thin film magnetic head according to claim 1, wherein the connection core is formed thicker than the side core. 3. After forming the protective film according to claim 1,
A second non-magnetic substrate is further adhered on the protective film, the core is cut by inclining the first non-magnetic substrate by a predetermined azimuth angle, and the cut surface is polished to form a gap. 3. The method for manufacturing an azimuth thin film magnetic head according to claim 1, wherein both the cut pieces are adhered. 4. A pair of connecting cores, a thin film coil and a side core are sequentially arranged on a first non-magnetic substrate with a space defined in the track scanning direction at symmetrical positions with an inorganic insulating film interposed therebetween. After forming and further forming a protective film, each core is cut by inclining the first non-magnetic substrate by different predetermined azimuth angles, and the cut surface is polished to form a gap, A method for manufacturing a double azimuth thin film magnetic head, characterized in that cut pieces are adhered. 5. The method of manufacturing a double azimuth thin film magnetic head according to claim 4, wherein the thickness of the connection core is made thicker than the thickness of the side core. 6. After forming the protective film according to claim 4,
A second non-magnetic substrate is further adhered onto the protective film, each core is cut by inclining the first non-magnetic substrate by different predetermined azimuth angles, and the cut surface is polished to form a gap. A method for manufacturing a double azimuth thin film magnetic head, characterized in that the cut pieces are adhered after performing.