JPH0618053B2 - Thin film magnetic head - Google Patents

Description

The present invention relates to a thin film magnetic head using a magnetic thin film.

[Background of the Invention]

With the improvement of the recording density of video tape recorders, an azimuth recording method has been developed in which the magnetization direction is made different between adjacent tracks, and this is the mainstream of the recording methods of video tape recorders, but to further improve the recording density, It is required to develop a magnetic head having a short gap length and a narrow track width by using a soft magnetic thin film such as permalloy, sendust, and amorphous as a head core material. As a method of forming the gap of this magnetic head, a gap bonding method by mechanical butting is generally used, but in addition to this, thin film technology is used to form a groove by bite cutting or the like, and the slope portion of the groove is formed. There is proposed a laminated thin film magnetic head using a laminated gap forming method, which is used as a gap surface, and a magnetic thin film is laminated after a gap spacer is deposited (JP-A-57-141011).

FIG. 3 is a view of the laminated thin-film magnetic head according to the above-mentioned prior art as seen from the tape sliding surface, where 1 is a non-magnetic substrate,
Reference numeral 2 is a first soft magnetic thin film, 3 is a V-shaped groove, 4 is a gap spacer film, 5 is a second soft magnetic thin film, 6 is a discontinuous surface, and 7 is a non-magnetic film. In the figure, this thin-film magnetic head has a non-magnetic film 7 formed on a non-magnetic substrate 1 and a first non-magnetic film 7 formed thereon.
Of the soft magnetic thin film 2 of
A V-shaped groove 3 is formed in a part of the soft magnetic thin film 2 of
The gap spacer film 4 is deposited on one slope of the V-shaped groove 3, and the second soft magnetic thin film 5 is further deposited on the inclined surface so as to fill the V-shaped groove 3, and the gap spacer film 4 is deposited. V
The magnetic gap is formed by removing the second soft magnetic thin film 5 only in the portion directly above the slope of the V-shaped groove 3, and the nonmagnetic protective film 13 is finally applied to manufacture the magnetic gap. However, in such a structure, it is difficult to fill the V-shaped groove 3 with the second soft magnetic thin film 5 without a discontinuous surface, and the discontinuous surface 6 functions as an unnecessary magnetic gap. Then, there is a problem that it interferes with the main magnetic gap. The generation of the discontinuous surface 6 depends on the angle θ formed by the two slopes of the bottom of the V-shaped groove. The larger the angle θ, the less the generation of the discontinuous surface. Therefore, as shown in FIG. 4, a step or a depression is provided in the non-magnetic substrate 1 to form the first soft magnetic thin film 2
As a trapezoidal shape, and the magnetic gap surface is located at the ridge of this step or indentation, the slope of the V-shaped groove 3 on the side that is not the magnetic gap surface is a non-magnetic substrate as shown by l in the figure. There has been proposed a method of increasing the angle θ by forming the angle θ ′ from a position lower than the initial surface of No. 1 (JP-A-59-3716).

However, in this method, the distance l between the two ridges of the trapezoidal groove 3'exposed by the removal of the first soft magnetic thin film 2 is set to at least the track width or the angle θ between the two ridges. , Θ ', if at least one of them is not more than 180 °, it is difficult to fill the three soft slopes of the trapezoidal groove 3'with the second soft magnetic thin film without discontinuity. However, at least one of the angles θ and θ ′ of the two ridges is 18
It is structurally impossible to set the angle to 0 ° or more, and increasing the distance l between the two ridges results in an increase in the removal volume of the first soft magnetic thin film, which results in a cutting tool life due to cutting removal. Cause deterioration of the film and peeling of the film. In addition, the non-magnetic substrate 1
Due to the drawbacks such as the need for special processing such as making a step or a dent on the surface, it was not possible to mass-produce a high-output thin-film magnetic head.

[Object of the Invention]

The object of the present invention is to eliminate the above-mentioned drawbacks of the prior art, to prevent the formation of a discontinuous surface in the groove portion when the second soft magnetic thin film is formed, to prevent interference by the discontinuous surface, and to achieve good characteristics and mass productivity. In order to provide a good thin film magnetic head.

[Outline of Invention]

In order to achieve this object, the present invention provides a second soft magnetic thin film by providing a gentle hill-shaped non-magnetic film layer in the vicinity of a magnetic gap surface on a non-magnetic substrate constituting a thin film magnetic head. The feature is that it can be formed without forming a discontinuous surface.

Example of Invention

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

FIG. 1 is a view of an embodiment of a thin film magnetic head according to the present invention as seen from its tape sliding surface, where 1 is a non-magnetic substrate and 2 is a magnetic substrate.
Is a first soft magnetic thin film, 3 ″ is a groove, 4 is a gap spacer film, 5 is a second soft magnetic thin film, 7 is a non-magnetic film layer, 10 is a magnetic gap surface, and 13 is a protective film.

In the figure, a gentle hill-shaped nonmagnetic film layer 7 is formed in the vicinity of the gap surface 10 on the nonmagnetic substrate 1 so that a discontinuous surface does not occur when the second soft magnetic thin film 5 is deposited. To
The non-magnetic film layer 7 may be deposited on the entire surface of the non-magnetic substrate 1 as long as it is raised in the shape of a gentle hill near the gap surface 10. Further, when the gap surface 10 is formed, the groove 3 that is processed by cutting with a bite or the like has a shape that penetrates at least the first soft magnetic thin film 2, and the angle between the two ridge lines formed by this groove processing is , The angle θ formed by the gap surface 10 and the non-magnetic film layer 7 when viewed from the second soft magnetic thin film 5 side.
Is 90 ° or more, and the angle θ ′ formed by the grooved surface and the other surface on the nonmagnetic film layer 7 as viewed from the second soft magnetic thin film 5 side is 180 ° or more.

Next, a manufacturing process of an embodiment of the thin film magnetic head according to the present invention will be described with reference to FIGS.

(A) First, the mask 8 is placed at a position where a magnetic gap is finally formed on the non-magnetic substrate 1 such as glass shown in FIG. The non-magnetic film layer 7 is deposited and formed in the shape of a gentle hill by sputtering.

(B) Next, as shown in FIG. 6 (c), a mask 8'is positioned on the left or right side of the center of the non-magnetic film layer 7, and the first soft magnetic thin film 2 is covered by mask sputtering. Form.

(C) The first soft magnetic thin film 2 that has been formed by adhesion is cut with a cutting tool 9 such as diamond that is easy to cut with high precision.
A part of the step slope portion of the soft magnetic thin film 2 is removed at least until it reaches the nonmagnetic film layer 7 to form the magnetic gap surface 10 (d). At this time, the angle of the cutting edge 11 formed by the surface forming the magnetic gap surface 10 of the cutting tool 9 and the bottom surface is made as large as possible, and at the same time, the non-magnetic film layer 7 is formed by the cutting edge 12 on the side opposite to the cutting edge 11. So that it is not substantially cut. As shown in (e), the groove 3 formed by the bite machining is formed by the bite cutting while the angle θ of the ridge formed by the magnetic gap surface 10 and the bottom surface (the upper surface of the non-magnetic film layer 7) is large. The angle θ'of the other ridge becomes 180 ° or more, and the distance l between the two ridges can be shortened.

(D) Next, as shown in (f), a gap spacer film 4 is deposited by sputtering or the like so as to cover the first soft magnetic film 2 and the groove 3, and a mask 8 ″ is placed on the same as shown in FIG. Second place
The soft magnetic thin film 5 is deposited only on the groove 3 and the upper part of the magnetic gap surface 10.

(E) The second soft magnetic thin film 5 formed by deposition is removed by wrapping or the like only on the upper part of the magnetic gap 10. At this time, the gap spacer film 4 on the first soft magnetic thin film 2 is also removed (g).

(F) In order to protect the exposed upper surface of the first soft magnetic thin film 2 and the upper surface of the second soft magnetic thin film 5, a protective film 13 such as glass is formed by covering these soft magnetic thin films. Yes (h).

A laminated thin film magnetic head is manufactured through the above steps.

〔The invention's effect〕

As described above, according to the present invention, the first soft magnetic thin film and the magnetic gap surface of the groove formed by the bite processing on the nonmagnetic film layer deposited on the nonmagnetic substrate which is the substrate are formed. The angle of the ridge with the bottom can be made large, and at the same time, the other ridge angle produced by cutting the bite is 180 ° or more, and the distance between the two ridge lines can be shortened, making it a special magnetic substrate. Since the second soft magnetic thin film can be filled without discontinuity without requiring special processing, shortening the tool life, and film peeling, eliminating the discontinuity surface of the magnetic core that interferes with the main gap. It is possible to provide a thin film magnetic head having excellent functions, excluding the above-mentioned drawbacks of the prior art.

[Brief description of drawings]

FIG. 1 is a view of an embodiment of a laminated thin film magnetic head according to the present invention as viewed from the tape sliding surface side, and FIG. 2 is a manufacturing process diagram of the laminated thin film magnetic head according to the present invention, FIGS.
The figure is a view of a laminated thin-film magnetic head according to the prior art as seen from its tape sliding surface. 1 ... Non-magnetic substrate, 2 ... First soft magnetic thin film, 3 ... Groove, 4 ... Gap spacer film, 5 ... Second soft magnetic thin film, 6 ... Discontinuous surface, 7 ... Non Magnetic film layer, 8, 8 ', 8 "... Mask, 9 ... Bit, 10 ... Magnetic gap surface, 11 ... Bit edge, 12 ... Bit edge, 13 ... Protective film.

Claims (2)

[Claims] 1. A non-magnetic substrate, a first soft magnetic thin film deposited on the non-magnetic substrate, and a part of the first soft magnetic thin film is removed by cutting, and the non-magnetic substrate is deposited via a gap spacer. And a second soft magnetic thin film, wherein a magnetic gap is formed by the first and second soft magnetic thin films via the gap spacer, in a flat thin film magnetic head on the non-magnetic substrate. The non-magnetic film layer having the gentle hill is provided so that the top of the gently hill-shaped non-magnetic film layer is located near the magnetic gap, and the ridgeline of the first soft magnetic thin film removed by the cutting process and the ridge line The angle formed by the ridgeline of the second soft magnetic thin film deposited on the nonmagnetic film layer is defined as the first
The thin film magnetic head is characterized in that the angle between the ridge of the soft magnetic thin film and the flat surface of the non-magnetic substrate is made larger. 2. A thin-film magnetic head according to claim 1, wherein a ridge line of the first soft magnetic thin film and a second soft magnetic thin film on a non-magnetic film layer which is continuous with the ridge line and cut. The angle θ formed by the ridgeline is 90 ° or more, and the angle θ ′ formed by the ridgeline of the second soft magnetic thin film that has been cut and the ridgeline of the second soft magnetic thin film that is not cut is the second soft magnetic thin film. A thin-film magnetic head characterized by being set to 180 ° or more when viewed from the side.