JPH0485715A - Inline multigap magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To increase the depth of a magnetic gap by providing a thin-film coil, a 1st thin magnetic film formed on at least one end face of 1st and 2nd members and a 2nd thin magnetic film formed to position in the magnetic gap forming region corresponding to the thin magnetic film layer. CONSTITUTION:The thin magnetic films 24, 25 form magnetic gap between the 1st and 2nd members 21 and 22 by the mechanical joining of these members 21, 22 and, therefore, the magnetic gap of a prescribed gap length cannot be formed unless the thin magnetic films project from the thin-film coil 23 and an insulating film 27 in the back gap part and the front gap part. The thin films 24, 25 come into contact with the 2nd member 22 when the member 21 and the member 22 are joined if the thin films 24, 25 are formed on the member 21. On the other hand, a groove 29 for preventing the leakage of magnetic fluxes corresponding to the winding hole of an ordinary bulk type magnetic head is formed by a method, such as cutting, on the member 22 and further, the unnecessary parts shown by a broken line are cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention (Field of Industrial Application) This invention relates to an in-line multi-gap magnetic head and a method for manufacturing the same.

(Prior Art) An inline multi-gap magnetic head is a magnetic head that has a plurality of magnetic gaps arranged on the same straight line, and is used in recording and reproducing heads for video floppies, which are used as recording media in electronic still cameras. ing. Television Society Technical Report “Image Information Recording J 198
8゜vol, 1B, P, 15 "Core magnetic properties and head properties of thin film inline dual gap magnetic head"
describes an example of realizing such an in-line multi-gap magnetic head using thin film technology.

However, in this conventional thin-film inline dual-gap magnetic head, the coil and magnetic core are both formed of thin films by sputtering, etc., so the core thickness (
It is difficult to increase the thickness of the magnetic core at the magnetic gap.

For this reason, if the gap depth is increased to apply to a system with a large amount of head wear, such as a rotary scanning VTR represented by a helical scan method, the magnetic core becomes more likely to undergo magnetic saturation, and the magnetic reluctance of the core increases. Due to the increase, the regeneration efficiency decreases.

(Problems to be Solved by the Invention) As mentioned above, in in-line multi-gap magnetic heads using conventional thin-film coils and thin-film magnetic cores, it is difficult to make the core thick, so if the gap depth is increased, the core There is a problem in that magnetic saturation tends to occur, reducing playback efficiency, and it is difficult to apply this method to systems such as VTRs, which have large head wear.

SUMMARY OF THE INVENTION An object of the present invention is to provide an in-line multi-gap magnetic head that can increase the gap depth by increasing the core thickness while taking advantage of the features of the thin-film magnetic head, and a method for manufacturing the same.

[Structure of the Invention (Means for Solving the Problems) In order to solve the above problems, an inline multi-gap magnetic head according to the present invention has at least two magnetic thin film layers each formed with at least one magnetic thin film layer serving as a magnetic core. Each member is constructed by joining two non-magnetic substrates with a spacer interposed between magnetic thin film layers, and includes first and second members with predetermined end faces facing each other.

A plurality of thin film coils are formed on the end surface of the first member corresponding to the magnetic thin film layer on each nonmagnetic substrate, and on the end surface of at least one of the first and second members,
A first magnetic thin film is formed inside the thin film coil, and a second magnetic thin film is formed in a magnetic gap forming region corresponding to the magnetic thin film layer on each nonmagnetic substrate.

Further, in manufacturing such an in-line multi-gap magnetic head, in the present invention, at least one magnetic thin film layer is formed on each of the first and second non-magnetic substrates, and then the first and second non-magnetic substrates are The upper magnetic thin film layers are bonded to each other via a spacer to obtain a bonded body. This joined body is separated into first and second members by cutting in a direction perpendicular to one side thereof and at a predetermined angle with respect to the joint surface. Next, a plurality of thin film coils are formed on the cut end surface of the first member corresponding to the magnetic thin film layer on each non-magnetic substrate, and a plurality of thin film coils are formed on the cut end surface of at least one of the first and second members. A first magnetic thin film is formed inside the thin film coil, and a second magnetic thin film is formed in a magnetic gap forming region corresponding to the magnetic thin film layer on each nonmagnetic substrate. And the first
The cut end surface of the second member is joined to the cut end surface of the second member so that a magnetic gap is formed between the two members in the magnetic gap forming region.

In a manufacturing method according to another aspect of the present invention, a plurality of nonmagnetic substrates each having at least one magnetic thin film layer formed thereon are stacked and bonded via a spacer to obtain a first bonded body. This first
Separate the joined body into the first and second members in the same manner as before, and apply the thin film coil, first magnetic thin film, and second magnetic film on the cut end surfaces of the first and second members in the same manner as before. After forming the thin film, both members are joined to obtain a second joined body. Then, this second bonded body is sliced to include a plurality of thin film coils and a plurality of magnetic gaps, respectively, to produce a plurality of inline multi-gap magnetic heads.

(Function) In the in-line multi-gap magnetic head according to the present invention, a magnetic gap is formed facing the end face of a magnetic thin film layer formed on a non-magnetic substrate. In this case, the magnetic gap formed by the magnetic thin film layer is The core thickness is a dimension in the in-plane direction of the magnetic thin film layer, and can be easily set larger than that in the film thickness direction. Therefore, it is possible to increase the depth of the magnetic gap without causing magnetic saturation of the magnetic core.

(Example) As an example of the present invention, the manufacturing process and structure of an in-line dual magnetic head having two magnetic gaps based on the present invention will be described.

First, as shown in FIGS. 1(a) and 1(b), two heat-resistant non-magnetic substrates 11 and 12 are prepared, and a plurality of magnetic thin film layers 13 are placed on each of them with an insulating layer 14 interposed therebetween. Laminated,
Furthermore, a spacer film 15 is formed on one side. The magnetic thin film layer 13 serves as a magnetic core, and is made of a metal ferromagnetic thin film, for example, a FeAlSi film with a thickness of several μm.The insulating layer 14 is made of a 5in2 film with a thickness of, for example, 0.5 μm, and both are sputtered or vacuum-treated. Formed by vapor deposition. In this case, the thickness and number of laminated layers of the magnetic thin film layer 13 and the insulating layer 14 are set so that the total thickness of the laminated film is approximately equal to the gap width (corresponding to the track width on the magnetic tape).

The spacer film 15 divides the track interval on the tape formed by the two magnetic gaps of the magnetic head by a predetermined distance, that is, an integral multiple of the track pitch (the track pitch is 20 μm).
For example, a 5in2 film is used.

Next, as shown in FIG. 2, the non-magnetic substrates 11 and 12 shown in FIGS. , that is, in a direction perpendicular to one side A and at an angle corresponding to the azimuth angle with respect to the joint surface B. Thereafter, the cut end surfaces are mirror-finished to obtain two parallelogram blocks as shown in FIG. These two blocks are the first and second members 21 and 22.

Next, as shown in FIGS. 4 and 5, the first member 2
A spiral thin film coil 23 is formed on the mirror-finished cut end surface of No. 1 by a manufacturing process similar to that of conventionally known normal thin film magnetic heads. The first magnetic thin film 24, the second magnetic thin film 25 located in the magnetic gear forming part which is the front gap part, and the bonding pad 2
6 and an insulating film 27 are formed.

That is, a first layer insulating film is formed on the entire surface of the first member 21 by sputtering or vapor deposition, and after patterning using photolithography technology, a conductive film such as C is formed.
A thin film 23 is formed over the entire surface by sputtering or vapor deposition, and patterned using photolithography to form a thin film coil 23 and a bonding pad 26. After this, a second layer insulating film is formed and patterned in the same way, and then
A metal ferromagnetic thin film, for example a FeAlSi film, is formed over the entire surface and patterned to form magnetic thin films 24 and 25. The thin film coil 23 and the magnetic thin films 24 and 25 are provided on the magnetic core portion of the first member 21, that is, on the end surface of the magnetic thin film layer 13. Then, a magnetic gap spacer film 28 made of an insulating film, for example, a SiO2 film is formed on the magnetic thin film 25 in the front gap portion.

Here, when compared with the manufacturing process of a conventional thin film magnetic head, the difference is that the first and second magnetic thin films 24.degree. 25 are formed. In the present invention, these magnetic thin films 24 and 25 form a magnetic gap between the first and second members 21 and 22 by mechanically joining them, so they are formed in the pack gap portion and the front gap portion. If the magnetic thin film does not protrude from the thin film coil 23 or the insulating film 27,
This is because a magnetic gap with a predetermined gap length cannot be formed.

When these magnetic thin films 24 and 25 are formed on the first member 21, the first member 21 and the second member 2 are formed as described below.
2, the magnetic thin films 24 and 25 are bonded to the second member 2.
Contact with 2.

On the other hand, as shown in FIG. 6, magnetic flux leakage prevention grooves 29, which correspond to the winding holes in a normal bulk magnetic head, are formed in the second member 22 by a method such as cutting, and unnecessary portions shown by broken lines are formed in the second member 22. Separate.

Next, as shown in FIGS. 4 and 5, the thin film coil 2
3. First member 21 on which magnetic thin films 24, 25, bonding pads 26, insulating film 27 and magnetic gap spacer film 28 are formed, and winding holes 29 are formed as shown in FIG. 6, and unnecessary parts are removed. The cut end surfaces of the mirror-finished second member 22 are made to face each other, and as shown in FIG. 7, they are joined and integrated by fusion using glass 30. Then, as shown by the broken line in FIG. 7, the magnetic gap spacer film 2
By processing the end surface on the side where 8 is formed into a predetermined curved surface, a sliding surface with respect to the magnetic tape is formed.

Through the above steps, a head chip 31 having a predetermined azimuth angle θ and two magnetic gaps formed on the same straight line is obtained as shown in FIG.

Next, as shown in FIG. 9, the head chip 31 shown in FIG. 8 is mounted on a commonly used head base plate 32 by adhesive or other method, and the lead wires 33 and wires 34 on the head base plate 32 are attached. If the wires are connected by bonding or the like, an in-line dual gap magnetic head is completed.

The present invention can also be applied to an in-line multi-gap magnetic head with three or more gaps. For example, when manufacturing a magnetic head with 3 gaps, the first
As shown in FIG. 0(a), a spacer film 15 is also formed on the laminated film of the magnetic thin film layer 13 and the insulating layer 14 on the first magnetic substrate 11 shown in FIG. 1(a), and Figure 10 (b>
As shown in FIG. 1(b), the second magnetic substrate 1 shown in FIG.
A laminated film of a magnetic thin film layer 13 and an insulating layer 14 is further formed on the spacer film 15 on the top layer 2.

10(a) (b) as shown in FIG. 11.
The non-magnetic substrates 11 and 12 shown in 2 are joined by glass fusion etc., and then the same steps as in the previous example are carried out using the first and second members obtained by cutting the joined body 40. By doing so, an in-line magnetic head having three magnetic gaps can be obtained.

In the above embodiments, a case has been described in which a single in-line multi-gap magnetic head is manufactured.

Next, a method for simultaneously manufacturing a plurality of inline multi-gap magnetic heads will be described. As shown in FIG. 12, a magnetic thin film layer 43 and an insulating layer 44 are formed on both sides of a non-magnetic substrate 42 having a relatively large heat resistance of, for example, about 1 inch square.
A laminated film is formed, and a spacer 45 is formed on one of the laminated films.

A large number of blocks 41 shown in FIG. 12 are prepared, and the first
After stacking and joining as shown in FIG. 3, the obtained joined body 46 is cut to produce a large number of first and second members similar to those in the previous embodiment.

Next, as shown in FIG. 14, a fourth
The thin film coil 23, the first magnetic thin film 24, the second magnetic thin film 25, and the bonding pad 2 explained in FIGS.
6. A large number of noturns 3 consisting of an insulating film 27 and a magnetic gap spacer film 28 are formed. Then, as shown in FIG. 15, after joining the first member 51 and the second member 52 in which the magnetic flux leakage prevention groove 29 described in FIG. Slice along the chain line and divide into head chips.

Considering the size of one Herad chip, this embodiment has advantages over the previous embodiments in that lithography and machining are easier and mass production is easier. Note that when forming laminated films on both sides of the nonmagnetic substrate 42 as described above, a conductive film may be used as the spacer 45. This will result in less crosstalk between the two gaps.

Still another embodiment of the present invention will be described. As shown in FIG. 16, the first member 51 shown in FIG. 13 and the second member 52 shown in FIG. 15 are made thinner to form a non-magnetic substrate 61 (62).
After embedding the first member 51 in multiple rows in multiple rows, as shown in FIG. Process as shown to obtain a head chip. Although this method requires more man-hours, it suppresses an unnecessarily large size of the magnetic thin film layer that forms the magnetic core, suppresses an increase in inductance due to magnetic flux leakage from the magnetic core, and improves the S/N at high frequencies. There is an advantage to doing so.

In addition, in each of the above-mentioned embodiments, the magnetic thin film layers serving as the magnetic core were laminated with an insulating layer interposed in between, but this was done in order to make it difficult for eddy current to flow through the magnetic core. If there is no need to take this into consideration, a single layer may be used.

Further, although the first and second magnetic thin films 24.25 are formed on the first member 21, it goes without saying that they may be formed on the second member 22. One may be formed in the first member 21 and the other in the second member 22, and one or both of the magnetic thin films 24.25 may be formed in both the first and second members 21.22. You may.

The magnetic head of the present invention can be applied not only to VTRs but also to video floppy disk devices. In that case,
Although the sliding surface with the medium and the shape of the head assembly are slightly different from those in the previous embodiment, the basic structure and manufacturing process of the head may be the same as those for a VTR head.

In addition, the present invention can be modified and implemented in various ways without departing from the scope of the invention.

[Effects of the Invention] According to the present invention, although the head is basically a thin film head, the core thickness of the magnetic core composed of a magnetic thin film layer can be easily increased, so the problem of magnetic saturation of the magnetic core can be solved. It is possible to increase the gap depth without
It is possible to provide an in-line multi-gap magnetic head suitable for a system such as a TR that has a large amount of head wear.

[Brief explanation of the drawing]

1 to 9 are diagrams for explaining the manufacturing process of an in-line multi-gap magnetic head according to a first embodiment of the present invention, and FIGS. 1(a) and 9(b) show the starting substrate of the head chip. Figure 2 is a cross-sectional view of two non-magnetic substrates.
FIG. 3 is a perspective view of a joined body obtained by joining the two non-magnetic substrates shown in FIGS. Fig. 4 is a perspective view showing a thin film pattern formed on the first member, Fig. 5 is a sectional view taken along line C-C in Fig. 4, and Fig. 6 is a state in which the second member has been processed. Figure 7 is a sectional view of the main parts of the Herad chip, Figures 8 (a) and (b) are perspective and front views showing the entire head chip, and Figures 9 (a) and (b) are the Herad chip. FIGS. 10(a) and 10(b) are bottom and front views of a completed magnetic head mounted on a head base. Cross-sectional view, Figure 11 is Figure 10(a)
(b) A perspective view of a joined body made by joining two non-magnetic substrates,
12 to 15 are diagrams for explaining the manufacturing process of an in-line multi-gap magnetic head according to a third embodiment of the present invention, and FIG. 12 has a laminated film of a magnetic thin film layer and an insulating layer. A cross-sectional view of the non-magnetic substrate, FIG. 13 is a diagram showing the first bonded body, and FIG. 14 is a perspective view showing a state in which a thin film pattern is formed on the second member obtained by cutting the first bonded body. 15 is a perspective view of the second joined body, FIG. 16 is a diagram showing an intermediate step in the fourth embodiment of the present invention, and FIG. 17 is a diagram of the head chip obtained in the fourth embodiment. FIG. 11.12.42...Nonmagnetic substrate 13.43...Magnetic thin film layer 14.44...Insulating layer 15.45...Spacer 20.40...Joint body 21.22...No. 1. Second member 23...thin film coil 24.25...first and second magnetic thin films 26...ponding pad 27...insulating layer 28...magnetic gap spacer film 29...・Magnetic flux leakage prevention groove 30...Glass Fig. 4 (a) (b) Fig. (a) (b) Fig. 14 Slice surface Fig. 16

Claims (4)

[Claims] (1) Each of the bonded bodies is formed by joining at least two non-magnetic substrates each having at least one magnetic thin film layer formed thereon with a spacer interposed between the magnetic thin film layers, and are provided with predetermined end faces facing each other. a plurality of thin film coils formed on the end surface of the first member corresponding to the magnetic thin film layer on each nonmagnetic substrate; a first portion formed on at least one end surface of the member and located inside the thin film coil;
a second magnetic thin film formed on the end surface of at least one of the first and second members, located in a magnetic gap forming region corresponding to the magnetic thin film layer on each non-magnetic substrate. An in-line multi-gap magnetic head comprising: (2) forming at least one magnetic thin film layer on each of the first and second non-magnetic substrates; and connecting the magnetic thin film layers on the first and second non-magnetic substrates to each other via a spacer. a step of joining to obtain a joined body; a step of separating the joined body into first and second members by cutting the joined body in a direction perpendicular to one side thereof and inclined at a predetermined angle with respect to the joint surface; forming thin film coils on the cut end surface of one member, corresponding to the magnetic thin film layers on the first and second non-magnetic substrates; and cutting at least one of the first and second members. forming a first magnetic thin film on the end face, located inside the thin film coil; and forming the first and second non-magnetic film on the cut end face of at least one of the first and second members. forming a second magnetic thin film located in a magnetic gap forming region corresponding to each of the magnetic thin film layers on the substrate; A method for manufacturing an in-line multi-gap magnetic head, comprising the step of joining the first and second members so that a magnetic gap is formed between them in a gap forming region. (3) a step of stacking and bonding a plurality of non-magnetic substrates each having at least one magnetic thin film layer formed thereon via a spacer to obtain a first bonded body; and separating the first and second members by cutting in a direction inclined at a predetermined angle with respect to the bonding surface, and a magnetic thin film layer on each non-magnetic substrate on the cut end surface of the first member. forming a first magnetic thin film on the cut end surface of at least one of the first and second members so as to be located inside the thin film coil; , forming a second magnetic thin film on the cut end surface of at least one of the first and second members in a magnetic gap forming region corresponding to the magnetic thin film layer on each nonmagnetic substrate; A second joined body is formed by joining the cut end surface of the first member and the cut end surface of the second member such that a magnetic gap is formed between the first and second members in the magnetic gap forming region. and slicing the second bonded body so as to include a plurality of the thin film coils and a plurality of magnetic gaps, respectively. (4) The in-line multi-gap magnetic head according to claim 2 or 3, further comprising the step of forming a magnetic flux leakage prevention groove on the cut end surface of the second member at a position facing the thin film coil. Production method.