JPS61137212A - Thin film magnetic head for multi-track - Google Patents

Abstract

PURPOSE:To improve the density of tracks by distributing and arranging coil conductors close to the right and left end parts excluding the meshed parts of upper magnetic cores. CONSTITUTION:The coil conductors 2, 3 are distributed and arranged close to both the ends of the upper magnetic cores 4-7 so as to be intersected with the upper magnetic cores 5, 7 and 4, 6 respectively. The intersected parts of the coil conductor 3 at the lower surfaces of the upper magnetic cores 4, 6 are expanded positions exceeding up to magnetic gaps 8, 10 along the longitudinal direction of the upper magnetic cores 4, 6 to constitute expanded parts 3' and the coil conductor 2 are similarly expanded to constitute expanded parts 2'. Consequently, respective upper magnetic cores 4-7 can be arranged as close as possible independently of the existence of the coil conductors 2, 3 and the density of tracks can be improved in accordance with said adjacent arrangement.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention J] The present invention relates to a thin film multi-track magnetic head with high track density used in magnetic tape storage devices and the like.

[Background of the invention]

Conventionally, the following three types of thin film magnetic heads are known. Its first form is rIBM
, Disk, Storage, Technology J (February 1980), pages 6 to 9, or ``Journal, on the Applied, Physics'', Vol. 53, No. 3 (1).
As shown in pages 2611 to 2613 of ``March 982'', a coil conductor and a part of the coil conductor are covered across the coil conductor and a part of the coil conductor by thin film formation technology on a magnetic substrate that becomes the lower magnetic core. The second type is one in which an upper magnetic core is formed, and the end of the joint surface between the upper magnetic core and the magnetic substrate is a magnetic gap. , M.A.
G-16, No. 5 (October 1980), pages 870 to 872, or Publication of Utility Model Publication No. 13255/1983, a so-called ring-shaped magnetic core is formed using a substrate construction thin film formation technique. It is formed by Due to the structure of these types of magnetic heads, although the track width or gap length can be processed with high precision using well-known thin film forming techniques (photolithography, X-vacuum deposition, /I'i sputtering, etc.), the gap Regarding the depth, it has the disadvantage that its accuracy must be achieved by mechanical polishing.

In contrast, the third
The structure of the magnetic core and coil conductor is almost the same as that of the first type, but the magnetic gap is different from that of the first type.
It is formed by magnetically cutting approximately the center of a strip-shaped upper magnetic core in its width direction, and the cap depth is determined by the film thickness of the upper magnetic core. Therefore, in the third type of magnetic head, the so-called gap-in-plane magnetic head, not only the track width and gap length but also the gap depth can be processed with high precision using thin film forming technology, and the magnetic head 11th for further miniaturization and higher precision
It has the feature of being

By the way, when a multi-track magnetic head is constructed by arranging a large number of thin film magnetic heads in parallel, problems arise in not only miniaturization and high precision of the individual magnetic heads but also in improving the arrangement density, that is, the track density.

Examples of multi-track thin-film magnetic heads include those described in the above-mentioned "Journal, on the Applied Physics," Vol. All of these belong to the first type of thin film magnetic head and require mechanical polishing of the gap depth.
There are limits to the miniaturization and high precision of each magnetic head, and furthermore, with this type of magnetic head, the above-mentioned structure d,
As is clear from the above, since the magnetic gap is located on one end surface of the magnetic core, when a plurality of such magnetic heads are arranged in parallel, each magnetic head is located between the magnetic cores of each adjacent magnetic head. However, due to the space occupied by the coil conductors, it was not possible to increase the track density very high.

[Purpose of the invention]

The purpose of the present invention is to eliminate the drawbacks of the above-mentioned prior art, miniaturize,
It is an object of the present invention to provide a thin film multi-track magnetic head which is capable of high precision and has a high track density.

[Summary of the invention]

In order to achieve this object, the present invention takes advantage of the features of the gear, in-plane type magnetic head and makes it into a multi-track magnetic head with a high track density. A plurality of strip-shaped upper magnetic cores in a type magnetic head are arranged in parallel to form a multi-track, and these upper magnetic cores are alternately shifted in the longitudinal direction and arranged so that a part of the longitudinal direction forms an interlocking part. At the same time, the coil conductors are arranged near both ends of each upper magnetic core so that the coil conductors intersect with each upper magnetic core at a position away from the above-mentioned meshing part. The first feature is that there is no noise that interferes with the close arrangement of the upper magnetic core. In this case, in the gap-in-plane magnetic head, the magnetic gap can be freely arranged and formed at any position on the upper magnetic core, so even if the upper magnetic cores are arranged alternately as described above, each upper The magnetic gaps for each magnetic core can be arranged in-line in accordance with the above-mentioned engaging portions, as in a normal multi-track magnetic head.

However, in this case, the magnetic gap formation position is outside the intersection of the upper magnetic core and the coil conductor, and the surface of the upper magnetic core is located at the soil area at the intersection with the coil conductor. Since it is lowered by the thickness of the coil conductor compared to the surface of the magnetic core, if this continues, the magnetic gap and the recording medium will not come into close contact with each other, resulting in a decrease in recording and reproducing efficiency. Therefore, in order to eliminate such drawbacks, the present invention extends the intersection portion of each coil conductor with the upper magnetic core along the longitudinal direction of the upper magnetic core beyond the arrangement position of the magnetic gap, thereby forming a magnetic gap. The second feature is that the step of the upper magnetic core at the position is eliminated.

[Embodiment J of the invention Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of the thin film multi-track magnetic field according to the present invention, in which 1 is a magnetic substrate serving as a lower magnetic core, 2 and 3 are electric conductors on the magnetic substrate 1. Coil conductor formed via an insulating layer (not shown) 2/,
3/ is its extended portion, 4 and 6 are electrical insulating layers 4, respectively.
A strip-shaped upper magnetic core 5.7 formed to cover across the coil conductor 3 via /, , S/ also extends across the coil conductor 2 via the electrically insulating layers 5', 7'. a band-shaped upper magnetic core formed to cover 8, 9;
, 10.11 are upper magnetic cores 4, 5, 6.7, respectively.
A magnetic gap formed by magnetically cutting the widthwise direction.

12, 13, and 14 are signal terminals derived from the coil conductor 3, and 15, 1 (S, 17 are signal terminals derived from the coil conductor 2).

As is clear from the figure, the upper magnetic cores 4 to 7 are disposed so as to be shifted from each other in the longitudinal direction, and a portion of the longitudinal direction engages with each other, and the magnetic gaps 8 to 1
1 are arranged in-line at the engaging portions of the respective upper magnetic cores 4 to 7.

The coil conductors 2 and 3 are connected to the upper magnetic cores 5°7 and 4.7 at positions apart from the engagement portions of the upper magnetic cores 4-7, respectively.
6, and are distributed near both ends of the upper magnetic cores 4 to 7.

In the illustrated embodiment, the coil conductor 2 is connected to the upper magnetic cores 5, 7.
However, in its operation, the coil conductor 2 is formed individually for each magnetic head constituted by the upper magnetic cores 5 and 7, with the signal terminal 16 as a common terminal. However, in some cases, the coil conductor 2 may be made independent and separate for each magnetic head. The same thing can be said about the other non-coil conductor 3.

In any case, the coil conductors 2 and 3 are connected to the upper magnetic core 4~
7), each upper magnetic core 4 to 7 is connected to the coil conductor 2, 3.
The track density can be increased to the extent that the tracks can be placed as close as possible regardless of the presence of the tracks.

The intersection portions of the coil conductors B on the lower surfaces of the upper magnetic cores 4 and 6 are the upper magnetic cores 4 and 6, respectively. Along the long direction of Otsu,
The coil conductor 2 is extended to a position beyond the magnetic gap 8.10 to constitute an extension 3', and the coil conductor 2 is similarly extended to constitute an extension 2'. A cross-sectional view of the extension portion 3' taken along the broken line AA' is shown in FIG. 2(A). As is clear from the figure, the height of the surface of the upper magnetic core 4 on the button extension part 3' is uniform in the range from the intersection with the coil conductor 3 to the magnetic gap 8.

If the extension part 3' is not provided, the height of the surface of the upper magnetic core 4 is high only at the intersection with the coil conductor 3, as shown in the cross-sectional view of FIG. Since the magnetic gap becomes low at the 8 portion, a gap is created between the magnetic gap 8 and a recording medium such as a magnetic tape, resulting in a decrease in recording and reproducing efficiency.

It is clear that the extensions 3' and 2' eliminate this inconvenience.

The manufacturing process of an embodiment of the non-invention shown in the figure 3.
The diagram will be explained.

1. As shown in FIG. 3(A), a magnetic substrate 1 (permalloy) which will become the lower magnetic core is formed on the substrate to a thickness of 10 μm by sputtering, and then S is used as an interlayer insulating material.
10. A film 18 is formed to a thickness of 2 μm (by sputtering method). Next button As shown in Figure 3 (B), the above 5i (ha)
18 is etched into the desired pattern. SiO
, in order not to deteriorate the characteristics of the film 18 and the magnetic substrate 1,
The taper angle of the 5in2 film 18 is preferably 60° or less, and preferably 25° or more from the viewpoint of recording and reproducing efficiency.

On top of this, place aluminum that will become the coil conductor to a thickness of 5 μm.
After forming, a desired pattern is formed, and a coil conductor 3 is provided as shown in FIG. 3(C).

Thereafter, a 5102 film that will become an insulating layer is formed to a thickness of 10 μm, and then formed into a desired pattern to provide an insulating layer 19 as shown in FIG. 3 (DlK). Then, as shown in FIG. 4 magnetic cores 4a and 4b and a magnetic gap 8 are formed.

These can be formed, for example, by the method disclosed in Japanese Patent Application Laid-Open No. 55-152519.

That is, first, a portion of the magnetic core 4 is formed by etching or the like, and then the whole is covered with a magnetic insulating layer.
After that, four magnetic cores 4bf are formed (by etching, etc.). Therefore, the magnetic insulating layer is interposed in the magnetic gap 8 portion, and the gap length of the magnetic gap 8 is determined by the thickness of the magnetic insulating layer.

Note that the magnetic insulating layer remaining on the surface of the magnetic core 4a is
It is appropriately removed by wrapping or the like.

The WiM magnetic head shown in FIG. 3 (R1) is finally processed into a desired head shape to complete a thin film magnetic head as a final product.

Although one embodiment of the present invention has been described above in the case of a four-track multi-track magnetic head, the present invention is not limited to such an embodiment, and can similarly be implemented even if the number of tracks is different. It goes without saying that there is.

[Effects of the Invention J As explained above, according to the present invention, the track width, gap length, and gap depth can be processed only by thin film forming technology, and therefore mass production is good and miniaturization is possible. This makes it possible to achieve high precision by distributing the coil conductors near the left and right ends of the upper magnetic core, away from the engaging part of the upper magnetic core. They can be placed close together, making it possible to increase the track density accordingly. Furthermore, the reduction in recording and reproducing efficiency due to the step difference in the gap forming part of the upper magnetic core, which occurs when the coil conductors are distributed, can be avoided by simply placing the coil conductors in one place. 12 can be easily solved by simply extending the section and without adding any special process. Therefore, it is possible to provide an excellent thin film multi-track magnetic head that eliminates the drawbacks of the above-mentioned prior art.

[Brief explanation of drawings]

Figure 1 is a perspective view showing an embodiment of the present invention, Figure 2 (A)
is a cross-sectional view along A-A' of Fig. 1, and Fig. 2 (B
) is a sectional view when the extension portion 3' of FIG. 2(A) is not provided, and FIG. 3 is a diagram for explaining the manufacturing process of the embodiment of FIG. 1. 1... Magnetic substrate, 2.3... Coil conductor, 2'.

Claims (1)

[Claims] A magnetic substrate serving as a lower magnetic core, a coil conductor provided on the substrate, a band-shaped upper magnetic core provided so as to cover the coil conductor across the coil conductor, and a magnetic substrate that covers the upper magnetic core in the width direction. In a thin film magnetic head having a magnetic gap formed by cutting the upper magnetic core into a plurality of magnetic cores arranged in parallel, the upper magnetic core is arranged alternately in the longitudinal direction so that a part of the longitudinal direction is the magnetic gaps are arranged in-line in each of the meshing parts, and the coil conductor intersects the respective upper magnetic core at a position outside the meshing part. are distributed and arranged near both ends of the upper magnetic core, and each intersection thereof extends beyond the arrangement position of the magnetic gaps along the longitudinal direction of the upper magnetic core. Thin film multi-track magnetic head.