JPH06180816A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To prevent the mixing of gaseous Ar into a mold glass to increase the joining strength of a gap and to increase the product yield by specifying the Ar pressure in sputtering to form a gap material layer. CONSTITUTION:The gap material layers 25 and 26 of SiO2 and the adjacent joining glass layers 27 and 28 are formed by sputtering on the abutting surfaces 18a and 19a of core halves 18 and 19. The layers 27 and 28 are butt-welded to form a gap 21 having a specified length L. A mold glass is filled in the part to be chamfered adjacent to the gap 21 to reinforce the gap 21. The Ar pressure is controlled to 4-15mTorr in sputtering to form the layers 25 and 26. The Ar is mixed into the layers 25 and 26 as bubbles when the Ar pressure is below the range, and the joining strength of the mold glass is lowered. Meanwhile, the discharge is unstable and the joining strength is increased, when the Ar pressure is above the range. Consequently, the product yield is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a method of manufacturing a magnetic head which is constructed by abutting and joining two core halves via a gap portion, and further reinforcing the gap portion with a mold glass. In particular, a Fe-Si-Al alloy magnetic film that is suitable for use in high-density recording heads for high frequencies, which require a high S / N ratio, mainly video heads, computer heads, etc., was used. It is preferably used for manufacturing a magnetic head.

[0002]

2. Description of the Related Art The recent improvement in recording density in the field of magnetic recording technology is accompanied by a consequent narrowing of tracks for a magnetic head as an electromagnetic transducer, an increase in saturation magnetization of a core material, and a transparency in a high frequency region. There is an increasing demand for improved magnetic susceptibility.

In recent years, for example, Fe--Si--Al has been used as a magnetic head satisfying the above requirements in the field of magnetic recording.
A thin film laminated magnetic head using an alloy magnetic film has been rapidly receiving attention. An example of such a magnetic head and its manufacturing method will be described with reference to FIGS.

Referring to FIG. 3, an Fe-Si-Al alloy thin film 12 is formed in a thickness of 1 to 20 μm on a substrate 11 made of crystallized glass or ceramics. Then, a non-magnetic insulating film made of SiO ₂ , that is, an interlayer film 13 is formed on the alloy magnetic film 12 to have a film thickness of 0.03 to 0.5 μm.

Further, the magnetic film 12 and the non-magnetic insulating film 13 are stacked a necessary number of times to form a magnetic film structure 14. The film thickness of the magnetic film 12 and the non-magnetic insulating film 13 and the number of times of lamination are appropriately set so that the thickness of the laminated portion becomes the track width W.

Next, a glass film 15 is formed on the magnetic film structure 14, and another substrate 16 is laminated thereon. Bonded glass is used as the glass film 15. The substrate 16 is made of the same material as the substrate 11.

Laminated film structure 1 produced in this way
2, a pair of core halves 18 and 19 are formed by cutting in the laminated thickness direction as shown in FIG. 2, and at least one of the core halves, in this example, the core half 18 has a winding groove. Form 20.

Subsequently, in order to strengthen the joining of the abutting surfaces of the two core halves 18 and 19, conventionally, as shown in FIG. A chamfered portion 22 is formed on both side surface portions of 19, and a recess 23 is formed on the opposite side of the winding grooves 20 of both core halves. After that, the abutting surfaces of both core halves 18 and 19 are polished,
The gap portion 21 is formed.

Conventionally, as shown in FIG. 1, the gap portion 21 has a gap portion forming surface of each of the core halves 18 and 19, that is,
A non-magnetic insulating layer made of SiO ₂ , that is, gap material layers 25 and 26, and bonding glass layers 27 and 28 are sequentially formed on the non-magnetic insulating layers adjacent to the abutting surfaces 18a and 19a by a sputtering method to form cores. It was formed by facing the bonded glass layers 27 and 28 of the halves 18 and 19 and melt-bonding them.

Further, the chamfered portion 22 and the recess 23 are filled with mold glass m to reinforce the joining of both core halves, that is, the joining strength of the gap portion 21.

Finally, for example, R polishing processing and other forming processing and winding processing are performed to form a tape sliding surface, and the magnetic head 10 is obtained.

[0012]

The magnetic head having such a structure has extremely good magnetic characteristics. Particularly, as described above, the chamfered portion 22 is filled with the mold glass m and the gap portion is formed. Although the gap 21 is reinforced, the gap 21 may be opened, which causes a reduction in yield in manufacturing the gap 21.

The inventors of the present invention have conducted research and experiments to solve this problem. As a result, Ar gas bubbles are present in the mold glass m of the gap portion 21, particularly the chamfered portion 22. It was found that the bonding strength of the glass m was deteriorated. As a result of further research experiments,
(1) When the relationship between the material of the sputtered film and the amount of Ar taken in was investigated, as shown in FIG. 5, especially in the gap material layers 25 and 26 made of SiO ₂ , Ar used during sputtering was found. Of the chamfered portion formed adjacent to the gap portion 21. (2) The Ar incorporated in the gap material layers 25 and 26 is much larger than that of the glass film or the aluminum film. 22 is released into the mold glass m as a gas and is retained as Ar bubbles in the mold glass m. (3) The Ar bubbles in the mold glass m affect the bonding strength of the mold glass m. It was found that the bonding strength of the gap portion 21 is reduced.

As a result of further research and experiments, the inventors of the present invention can significantly reduce the amount of Ar in the gap material layers 25 and 26 by setting the Ar gas pressure during sputtering to 4 to 15 mTorr. It has been found that this can reduce the amount of Ar gas released into the mold glass m, and thus can significantly improve the bonding strength of the mold glass m. Thereby, the gap portion 21
It was possible to drastically improve the yield related to the manufacture of the gap portion 21 by eliminating the gap.

The present invention has been made on the basis of such novel findings.

Therefore, an object of the present invention is to provide a method of manufacturing a magnetic head which can increase the bonding strength of the mold glass for reinforcing the gap portion, thereby significantly improving the yield relating to the manufacturing of the gap portion as compared with the conventional method. Is to provide.

[0017]

The above object can be achieved by the method of manufacturing a magnetic head according to the present invention. In summary, the present invention forms two core halves, the abutting surface of each core half having at least a gap material layer of SiO _{2 on the} core half side and adjacent to the gap material layer. A bonding glass layer and a bonding glass layer are sequentially formed by a sputtering method, and the bonding glass layers of both core halves are melt-bonded to each other to form a gap portion having a predetermined gap length, and further adjacent to the gap portion. In the method of manufacturing a magnetic head in which the chamfered portion produced by filling the mold glass with the chamfered portion is reinforced, the Ar gas pressure during sputtering is 4 to 15 mTorr when the gap material layer is formed. And a method for manufacturing a magnetic head.

Preferably, each of the core halves has one substrate, a magnetic film structure in which a Fe--Si--Al alloy magnetic film and an interlayer film are alternately laminated on the substrate, and the thin film structure. It is composed of a laminated film structure having a glass film laminated on the body and the other substrate laminated on the glass film.

[0019]

Next, a method of manufacturing a magnetic head according to the present invention will be described in more detail. In this embodiment, the manufactured magnetic head is a thin film laminated magnetic head using a Fe—Si—Al alloy magnetic film.

A laminated film structure 17 having a structure as shown in FIG.
Is produced in the same manner as in the conventional case using, for example, a DC magnetron sputtering apparatus.

That is, in the laminated film structure 17, for example, C
Non-magnetic ceramic substrate 1 containing oO-NiO as a main component
Fe-Si-Al alloy film 12 having a thickness of 1 to 20 μm
Is deposited at.

Then, the Fe-Si-Al alloy film 12 is formed.
An SiO ₂ film having a film thickness of 0.03 to 0.5 μm is formed thereon as an interlayer film (insulating film) 13.

Similarly, the magnetic film 1 is formed on the interlayer film 13.
The magnetic film structure 14 is obtained by repeating the 2 and the insulating film 13 a predetermined number of times, for example, four times. The total film thickness of the magnetic film structure 14 is usually set to 10 to 100 μm, and then heat treated.

Further, a film thickness of 1 is formed on the magnetic film structure 14.
A glass film 15 having a thickness of about μm is formed by a normal sputtering method or the like, and then another substrate 16 made of the same material as the substrate 11 is laminated on the glass film 15 and melt-pressed to form a laminated film. The structure 17 is produced.

Next, the laminated film structure 17 thus produced is cut in the laminated thickness direction to form a pair of core halves 18 and 19, as shown in FIG. 18
After forming the winding groove 20 in the core, chamfers 22 are formed on both side surfaces of the core half 19 facing the winding groove 20 in order to strengthen the joining of the abutting surfaces of the core halves 18 and 19. Is formed, and if necessary, a recess 23 is also formed on the opposite side of both core halves from the gap portion 21.

Next, the abutting surfaces 18a, 19a (FIG. 1) of both core half blocks 18, 19 are ground to form the gap portion 21.

The gap portion 21 is first formed in each core half body 1.
On the abutted surfaces 18a, 19a of 8 and 19 which are polished,
The gap material layers 25 and 26 made of SiO ₂ are formed by sputtering, and then the gap material layers 25 and 26 are formed.
Bonding glass layers 27 and 28 are formed adjacent to the substrate by sputtering. If necessary, an Al layer is sputtered as a buffer layer between the abutting surfaces 18a and 19a and the gap material layers 25 and 26, and between the gap material layers 25 and 26 and the bonding glass layers 27 and 28, respectively. Can also be formed.

Gap material layer 2 constituting the gap portion 21
5, 26 and the bonding glass layers 27, 28, each layer thickness including a buffer layer made of an Al layer may be arbitrarily selected depending on the size of the length (L) of the gap portion 21. You can

Gap material layers 25 and 26 made of SiO ₂
Is formed by the sputtering method as described above, but according to the present invention, the Ar gas pressure during sputtering is 4
~ 15 mTorr.

As can be understood from FIG. 5, when the Ar gas pressure during sputtering is less than 4 mTorr, SiO
_A large amount of Ar is taken into the gap material layers 25 and 26 made of ₂ , and this Ar is released to the mold glass m as a gas when the chamfered portion 22 is melt-filled with the mold glass m. As a result, the bonding strength of the mold glass m is reduced. On the other hand, when the Ar gas pressure during sputtering exceeds 15 mTorr, the discharge becomes unstable and normal sputtering cannot be maintained.

Bonding glass layer 2 in the gap 21
7, 28 can be deposited according to conventional materials and methods. For example, the bonding glass layers 27 and 28 can be formed at an Ar gas pressure of 6 to 10 mTorr during sputtering.

The gap material layers 25 and 26 are 0.05 to 0.
15 μm, the bonding glass layers 27 and 28 are 0.02 to 0.1
It can be formed with a thickness of 0 μm.

If an Al layer is formed as a buffer layer, aluminum (Al) can be used as a target and can be formed by an ordinary sputtering method.
The film thickness is usually 10 to 200Å, preferably 50.
~ 150Å

The core halves 18 and 19 in which the gap portion 21 is formed in this manner are chamfered portions 22 and recesses 23.
While the mold glass m is melt-filled, the gap part 21 is further heated at 500 ° C. to 650 ° C. for 30 minutes to 1 hour to perform melt compression bonding.

Finally, if necessary, the R thin film lapping process and other forming process and winding process are performed to form the tape sliding surface, and the thin film laminated magnetic head 10 can be obtained.

Although a large number of magnetic heads 10 were manufactured by the above method, the occurrence of defective products such as opening of the gap portion 21 was 10% or less, and the yield rate for manufacturing the gap portion was 9%.
It was 0 to 95%.

That is, according to the present invention, the gap portion 21 is extremely stably welded when the magnetic head is manufactured, and the gap portion 21 does not open due to insufficient adhesion of the mold glass m in the gap portion 21. It was possible to form the dimensionally shaped gap portion 21.

Next, the present invention will be described with reference to examples.

Example 1 A non-magnetic ceramic substrate containing CoO-NiO as a main component was used as the non-magnetic substrate 11, and a Fe-Si-Al alloy film 12 and a non-magnetic insulating film were formed on the substrate 11 by a DC magnetron sputtering apparatus. The films 13 were alternately laminated to form the alloy magnetic thin film 14. In this embodiment, SiO ₂ is used as the non-magnetic insulating film 13, and the thickness of the alloy magnetic thin film 14 is set to 20 μm which is the track width (W).

Then, the glass film 1 is formed on the alloy magnetic thin film 14.
5 was formed with a film thickness of 0.35 μm by a sputtering method. Further, a glass film 15 is formed on the other non-magnetic substrate 16 made of the same material as the substrate 11 with a film thickness of 0.35 μm by a sputtering method, and is stacked on the alloy magnetic film 14 to form a film 7.
A laminated film structure 17 was produced by pressure welding at 00 ° C.

Next, the laminated film structure 17 thus manufactured is cut in the laminated thickness direction to form a pair of core halves 18 and 19, as shown in FIG. Body 1
After the winding groove 20 is formed in the winding groove 8, the winding groove 20 is formed in order to strengthen the joining of the abutting surfaces of the core halves 18 and 19.
Chamfered portions 22 are formed on both side surfaces of the core half body 19 facing each other, and the gap portion 2 of both core half bodies 18 and 19 is formed.
A recess 23 was also formed on the side opposite to 1, and then the abutting surfaces 18a, 19a of the core halves 18, 19 were ground.

Subsequently, nonmagnetic gap material layers 25 and 26 made of SiO ₂ were formed on the abutting surfaces 18a and 19a of the core halves 18 and 19 by a sputtering method.

At this time, the sputtering of SiO ₂ is R
F magnetron sputtering equipment was used, a target having a diameter of 8 inches and a thickness of 5 mm was used, and the distance between the target and the abutting surfaces 18a and 19a of the core halves 18 and 19 was 7.
The gap material layers 25 and 26 having a thickness of 0.1 μm are obtained by changing the Ar gas pressure to various values with 0 mm and an input power of 300 W.
Was formed. The substrate temperature was 200 ° C., and the film formation rate was about 5 nm / min.

Various core halves 18 thus obtained,
The glass films 27, 2 on the gap material layers 25, 26 of 19
8 was formed with a film thickness of 0.05 μm.

In both core halves 18 and 19 in which the gap portion 21 is formed in this manner, the chamfered portion 22 and the recessed portion 23 are melt-filled with the mold glass m, and the gap portion 21 is in the range of 500 ° C to 650 ° C. It was melt-pressed by heating at 30 minutes to 1 hour.

Finally, the thin film laminated magnetic head 10 was manufactured by performing R polishing processing, other molding processing and winding processing to form a tape sliding surface.

Table 1 shows the results of testing the bonding characteristics of the gap portion of the magnetic head 10 produced by changing the Ar gas pressure in this way.

The amount of Ar in the gap material layers 25 and 26 can be reduced by setting the Ar gas pressure during sputtering to 4 to 15 mTorr, whereby the Ar gas bubbles in the mold glass m are substantially reduced. I was able to get rid of it. Further, from Table 1, according to the present invention, the gap portion 2
It can be seen that the yield of 1 is significantly improved. Further, the magnetic head 10 manufactured according to the present invention had extremely good electromagnetic conversion characteristics.

[0049]

[Table 1]

In each of the above embodiments, the magnetic film 1 of the magnetic head
Although 2 has been described in relation to the Fe-Si-Al alloy magnetic material, an amorphous magnetic material or an iron nitride magnetic material can be used in the same manner, and the substrates 11 and 16 can also be made of CoO-. It goes without saying that other non-magnetic ceramic substrates other than the non-magnetic ceramic substrate containing NiO as a main component or substrates such as crystallized glass can be used.

[0051]

According to the method of manufacturing a magnetic head of the present invention configured as described above, the Ar gas pressure during sputtering is 4 to 15 mTorr when the gap material layer is formed. Ar gas does not exist as bubbles in the mold glass adjacent to the material layer, and the bonding strength at the gap can be significantly improved. Therefore, according to the present invention, it is possible to dramatically improve the yield related to manufacturing the gap portion.

[Brief description of drawings]

FIG. 1 is a partially enlarged plan view of an example of a gap portion of a magnetic head manufactured according to the present invention.

FIG. 2 is a perspective view of an embodiment of a thin film laminated magnetic head manufactured according to the present invention.

FIG. 3 is a partial plan view showing a magnetic layer configuration of the magnetic head of FIG.

FIG. 4 is a plan view showing a gap portion of the magnetic head of FIG.

FIG. 5 is a diagram showing a relationship between a material of a sputtered film and an amount of Ar taken in.

[Explanation of symbols]

 10 Thin Film Multilayer Magnetic Head 18, 19 Core Half 21 Gap 22 Chamfer 25, 26 Gap Material Layer 27, 28 Bonding Glass Layer m Mold Glass

Claims (2)

[Claims] 1. Forming two core halves, a gap material layer made of SiO ₂ at least on the core half side on the abutting surface of each core half body, and a bonding glass layer adjacent to the gap material layer. And are sequentially formed by a sputtering method, and the bonded glass layers of both core halves are melt-pressed to each other to form a gap portion having a predetermined gap length, and further, are formed adjacent to the gap portion. In a method of manufacturing a magnetic head in which the chamfered portion is filled with mold glass to reinforce the gap portion, when forming the gap material layer, the Ar gas pressure during sputtering is 4 to 15 mTorr.
A method of manufacturing a magnetic head, wherein r is r. 2. Each of the core halves comprises one substrate, a magnetic film structure formed by alternately stacking a Fe—Si—Al alloy magnetic film and an interlayer film on the substrate, and the thin film structure. The method of manufacturing a magnetic head according to claim 1, comprising a laminated film structure having a glass film laminated on the glass film and the other substrate laminated on the glass film.