JPS62141609A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To reduce sputter time by half, to decrease internal stress of a magnetic film, to heighten accuracy of core flatness and to prevent coming off by joining a pair of core elements made by coating a metallic magnetic layer on an auxiliary substrate by sputtering with crystallized glass to constitute a pair of magnetic head core half bodies, and after opposing them to become desired head track width, and joining integrally the two core half bodies in a body by noncrystallized glass in a winding groove. CONSTITUTION:Magnetic layers 11, 11' are formed by sputtering on one face of two auxiliary substrates 10, 10' made of nonmagnetic material to make the total thickness desired head track width W, and at the same time, and joined with crystallized glass by heating at a temperature lower than crystallization temperature of the magnetic layer, and a laminated body 13 is constituted. Further, a pair of core half bodies 15a, 15b are formed by working a winding groove 14 formed by cutting the laminated body 13 along a line B-B'. Such pair of core half bodies 15a, 15b are butted on a magnetic gap face (g), and joining glass 16 on and near the magnetic gap face or in the winding groove 14 is heated at low temperature. Thus, a magnetic head 17 joined integrally in a body is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a metal core laminated magnetic head that is effective for use in magnetic recording and reproducing devices such as VTRs and DATs.

(Prior Art) In recent years, with the trend toward high-density recording in VTRs, so-called metal tapes with high coercive force have been put into practical use.

Therefore, the corresponding magnetic head also uses a metal magnetic material with a high saturation magnetic flux density, for example, a so-called metal core such as amorphous or sendust.

In a bulk state, the metal core has a large eddy current loss at high frequencies, and to prevent this loss, the metal core is formed in a layered manner on an auxiliary substrate using a film forming technique such as sputtering or vapor deposition.

FIG. 2 is a diagram showing an example of a conventional metal head and its manufacturing method.

FIG. 2(a) is a schematic diagram seen from the front of the head, in which the magnetic core forming the head track width W is sandwiched between upper and lower auxiliary substrates, and the magnetic gap g is formed by a pair of core halves bonded together by adhesive glass. It consists of

The specific manufacturing process will be explained using FIGS. 2(b) and 2(c).

That is, as shown in FIG. 2(b), a metal magnetic material with a thickness corresponding to the necessary head track width W is placed on one auxiliary substrate 1,
For example, the magnetic layer 2 is formed by sputtering amorphous material.

Then, a glass thin film 3 is interposed from above the magnetic layer 2,
By stacking another auxiliary substrate 1' and fusing the glass thin film 3, a metal core laminate 4 sandwiched between the auxiliary substrates 1 and 1' from above and below is constructed.

FIG. 2(c) shows such a metal core laminate 4 at A-A'
The core halves 5a and 5b were manufactured by cutting the core halves 5a and 5b.

That is, the conventional head uses such core halves 5a and 5b, and the necessary winding grooves 6 and magnetic gap forming surfaces are machined to form a magnetic head body as shown in FIG. 2(a). 7
It was manufactured.

(Problems to be Solved by the Invention) In the conventional manufacturing method described above, the formation of the metal magnetic layer (magnetic core) 2 having a thickness equivalent to the head track width W sandwiched between the auxiliary substrates 1 and 1' is Auxiliary board 1 which is one of the boards
This is a manufacturing method in which a film is formed over the entire thickness by sputtering.

However, such a sputtering method has an extremely slow film formation rate and is time consuming. This requires time to manufacture the magnetic core 2 and increases the manufacturing cost.

Furthermore, as the thickness of the magnetic film formed on the auxiliary substrate 1 becomes thicker,
Stress within the film thickness is inherent and stress is applied from the magnetic layer 2 to the auxiliary substrate 1, causing warpage and poor flatness.

Therefore, a gap 8 is created between the glass layer 2 and the other adhesion auxiliary substrate 1'', and in extreme cases, the auxiliary substrate 1
' had problems such as poor adhesion or peeling during processing.

Furthermore, as above, one of the auxiliary substrates 1 is made of metal magnetic F! J2
In the conventional technique of forming the entire thickness of the film, there is a problem in that the film thickness distribution differs depending on the location on the substrate 1, and a gap 8 is created in the same structure as the warpage.

The above-mentioned variations in the stress and film thickness distribution of the magnetic layer 2 lead to deterioration of the magnetic properties of the magnetic layer 2, which deteriorates the electromagnetic conversion characteristics of the magnetic head and the mechanical dimensions such as head 1 - rack width W. There were also problems such as poor accuracy that degraded the quality of the magnetic head.

(Means for solving the problem) In order to solve the above problem, the present invention divides the necessary head track width W into each of the upper and lower auxiliary substrates 1 and 1' which sandwich the metal magnetic layer 2. Form a sputtering film.

(Function) The present invention reduces the sputtering time of the metal magnetic layer 2 by half and shortens the manufacturing time by using the above means and structure.

Furthermore, by reducing the internal stress of the magnetic film and increasing the accuracy of core flatness by improving the film thickness distribution, the metal core laminate 4 is firmly bonded, preventing negative effects such as peeling, and ensuring a highly reliable head. do.

(Embodiment) FIG. 1 is an embodiment diagram showing a magnetic head according to the present invention and its manufacturing process, and shows an example of a video head manufacturing method.

Here, FIG. 1(a) shows a magnetic head, FIGS. 1(b) to 1(e) are manufacturing process diagrams of the laminated core.

The pair of core halves 15a and 15b are connected to the two auxiliary substrates 10.
Magnetic layers 11 and 11' are sputtered onto each of the magnetic layers 10' and bonded together with a crystallized adhesive glass layer 12.

Further, the core half pair has a magnetic gap g as a boundary,
They are bonded using glass with a lower melting point than the adhesive glass layer 12.

Hereinafter, a manufacturing method of an example of the present invention will be explained.

Figure 1(b) shows two auxiliary substrates made of non-magnetic material.
, to' by sputtering the magnetic layers 11, 11' so that the total thickness is the desired head track width W.
At least one of the magnetic layers 11
Crystallized glass is interposed thereon as an adhesive glass layer 12 by sputtering, and then the magnetic layer 11.11'' is bonded by heating at a temperature lower than the crystallization temperature of the magnetic layer, and is sandwiched between the auxiliary substrates. A laminated body 13 having a magnetic layer is constructed.

Further, the laminated body 13 is cut along the line B-B' with a diamond blade, and the winding grooves 14 are formed using a grindstone or the like, thereby forming a pair of core halves 15a and 15b.

Using such a pair of core halves 15a and 15b, the magnetic gap surfaces g are butted together, and the bonding glass 16 disposed on and near the magnetic gap surface or in the winding groove 14 is bonded to the magnetic layer and the magnetic layer adhesive glass layer 12. The magnetic head 17 is obtained by heating at the same or lower temperature than the crystallization temperature of both of the two.

Next, a case will be described in which the magnetic head 17 uses a Co--Nb--Zr based amorphous alloy.

Flat-processed auxiliary substrates 10 and 10' made of non-magnetic materials such as crystallized glass or ceramics are arranged on the same surface, and the amorphous material is sputtered at a rate of 60 to 100 minutes per minute.
Deposit at a rate of 100 people.

For example, if the track width is 15 μm according to the LP mode specification of an 8+am VTR, a thickness of half the track width is deposited on each auxiliary substrate. A so-called low melting point crystallized glass, which crystallizes at a temperature below the upper temperature (500 to 550°C), is deposited on the other amorphous surface 11 by sputtering to form a film of about 100'.
10,000 by heating and bonding at about 480°C for about 30 minutes, 10,000
A 15 μm amorphous laminate 13 with a glass insulating layer is produced.

Such a laminate 13 is cut to form core halves 15a and 15b.
, and perform the necessary shape and dimension processing for one core half,
Track alignment of the left and right amorphous cores is performed through a gap material such as glass, and the head track width W is adjusted.
The bonding glass 16 provided in the winding groove 14 from the gap surface is heated at 480° C., which is lower than the crystallization temperature of the amorphous, for 30 minutes to integrate both core halves, and the magnetic A head 17 is obtained.

Further, FIG. 1 (e
).

That is, it is basically the same as the 15 μm specification mentioned above,
On the auxiliary substrate 10.10', a 15 μm amorphous film, which is half of 30 μm, is deposited by sputtering.

However, in order to improve the high frequency characteristics of the amorphous core, it is preferable to use a laminated core in which an insulating layer is inserted within the 15 μm.

Therefore, when amorphous is sputtered to a thickness of 7.5 μm, approximately 100 μm of SiO□ insulating layer 18.1
After interposing 8' by sputtering, the remaining amorphous is subsequently sputtered to a thickness of 15 μm.

Moreover, in place of this 5102, low melting point crystallized glass may be sputtered similarly to the adhesive glass layer 12.

In any case, when the head track width W becomes thicker,
As mentioned above, it is possible to form a laminated core with the necessary interlayer insulating layer interposed, and by sandwiching them between auxiliary substrates and adhering them with crystallized glass on an amorphous layer, the laminated core can be made to withstand subsequent heat treatment. can have an adhesive force that does not vary.

As described above, the manufacturing method of the present invention has the effect of shortening the sputtering time as the rack width W becomes thicker, and the effect of preventing high frequency loss due to lamination and reducing internal stress of the core increases. It is something.

Therefore, the maximum effect can be exerted on future ultra-high frequency compatible (MUSE) heads.

In the above description, the method of forming the magnetic core by sputtering has been described, but it can also be similarly realized by thin film forming techniques such as vapor deposition and ion blasting.

Furthermore, the bonding glass was also interposed by sputtering, but it is also possible to use a vapor deposition method, a method in which fine glass powder is mixed with a solvent and applied, or a thin glass plate can be directly interposed and heat bonded.

In addition, in the above explanation, the case where the magnetic core is amorphous has been described, but other metal materials with high saturation magnetic flux density such as sendust can also be applied. Since a processing temperature of at least 800° C. or higher is acceptable, adhesive glass or bonded glass is widely effective.

(Effects of the Invention) As described above, in the magnetic head constructed by the manufacturing process of the present invention, the core forming the necessary head track width W can be formed in half the sputtering time, so the manufacturing time can be shortened and the cost of the head can be reduced. I can do it.

In addition, since the sputtered amorphous layers are bonded with crystallized glass, a laminated structure is created, which is effective in preventing eddy current loss, and the core lamination does not change even during post-process heat treatment such as gap formation. It is possible to obtain a track width W and a magnetic gap g with high dimensional accuracy, and therefore, there is an effect that a highly reliable magnetic head 17 can be manufactured.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of a magnetic head according to the present invention and its manufacturing process, and FIG. 2 is a diagram showing an example of a conventional metal head and its manufacturing method. 10, 10'... Auxiliary board, 11.11' ・
...Magnetic layer, 12...Adhesive glass layer, 13...Laminated body. 14... Winding groove, 15a, 15b... Core half, 1
6... Bonding glass, 17... Magnetic head, 18.1
8'...Insulating layer. Figure 1 to, to' Province line 1, 11'9I1 12 S force゛imakyu 1 14 Ling 4 15a, 15b Zuaki entry is also Figure 1 day

Claims (3)

[Claims] (1) A pair of core elements each having a metal magnetic layer deposited on an auxiliary substrate by sputtering, vapor deposition, etc. are used, and the metal magnetic layers of the core elements are overlapped with an adhesive layer of crystallized glass composition interposed therebetween, and the first The crystallized glass is bonded and bonded by heat treatment to form a composite core element, and the composite core element is further used to form a pair of magnetic head core halves with an end surface crossing between both auxiliary substrates as a gap forming surface, and at least After forming a winding groove through the adhesive layer on one of the core halves, the gap forming surface is smoothed and the glass or oxide metal layer with the required gap width is formed into the desired head track width. A magnetic head characterized in that both core halves are integrally joined by melting and bonding amorphous glass from an appropriate location such as a winding groove or an auxiliary substrate through a second heat treatment. manufacturing method. (2) The metal magnetic layer is made of an amorphous alloy, and the first and second heat treatments are performed at a temperature lower than the crystallization temperature of the amorphous alloy. Manufacturing method for magnetic heads. (3) A method for manufacturing a magnetic head according to claim (1), characterized in that a sendust alloy is used for the metal magnetic layer, and the second heat treatment temperature is performed at a higher temperature than the first heat treatment temperature.