JPH08180314A - Core thin-film magnetic head - Google Patents

Abstract

PURPOSE: To assure the mechanical strength of a magnetic gap part and to lessen the peeling of magnetic metallic thin films by holding the magnetic gap materials in the apex part of a winding window only by the magnetic metallic thin films. CONSTITUTION: The winding window 8 is formed on the opposite surfaces of a pair of nonmagnetic substrates 1, 1 and the metallic material thin films 3 which are magnetic paths are formed on the inner peripheral surface of the winding window 8. The winding window 8 is positioned and formed so that the magnetic gap materials 5 of the apex part 31 of the winding window 8 are held only by the magnetic metallic thin films 3. As the result, the nonmagnetic substrates 1, 1 do not face each other in the magnetic gap part and, therefore, the adjoining of the materials having a large difference in the coeff. of thermal expansion to each other in a restraining state in the magnetic gap part is averted and the damage of the magnetic gap members 5 by the internal stresses generated during the production stage, etc., by the difference in the coeff. of thermal expansion is prevented. The film thickness of the magnetic metallic thin films 3 or the angle of the magnetic metallic thin films 3 with the medium-sliding surfaces is specified, by which the further, the similar effects can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic head having a small inductance, and more particularly to a magnetic head having a magnetic core made of a metal magnetic thin film, which is suitable for high density recording having a small magnetic gap depth.

[0002]

2. Description of the Related Art In recent years, in the field of magnetic recording, there is an increasing demand for higher recording density, and higher data speed is also required. From this point, there has been a demand for forming a magnetic core using a magnetic material having a high magnetic permeability and a high saturation magnetic flux density and a magnetic head having a small inductance.

Particularly, recently, a core thin film magnetic head has been attracting attention as a magnetic head which can satisfy the above-mentioned performance while diverting the conventional method of manufacturing a bulk type magnetic head. Various types of core thin film magnetic heads have been proposed in which a magnetic core is formed of a magnetic thin film on a non-magnetic substrate, but from the viewpoint of reducing the inductance, the one described in Japanese Patent Publication No. 6-54528 is particularly preferable. Is attracting attention.
As shown in FIG. 7, this magnetic head is provided on opposite surfaces of a pair of non-magnetic substrates 1 and 1, and a magnetic thin film 3 serving as a magnetic core is formed along the winding window 8 on its inner peripheral surface to form a non-magnetic substrate 1. , 1
The magnetic thin film formed in the parallel facing portions 32, 32 above the upper winding window 8 holds the gap material to form the magnetic gap 5 and the magnetic head 34. As shown in FIG. 8, this type of magnetic head is manufactured by forming a winding groove 7 on a surface of a pair of nonmagnetic blocks facing each other using a dicer or the like (a), and FeAlSi, FeTaN, FeNi on this surface.
Metal magnetic thin films 3 and 3 are formed (b), and then SiO2, Al2O3 and the like 5 and 5 to be gap materials are sputtered,
The magnetic head is formed by vapor deposition (c) and integrated by glass bonding (d) to form a closed magnetic circuit of a metal magnetic thin film.

No special protective layer is formed on the metal magnetic thin film 3 formed on the non-magnetic substrate 1. Furthermore, as shown in FIG. 7, the angle 3 between the portion of the magnetic thin film that contacts the medium sliding surface and the medium sliding surface 35 is 3
No particular attention was paid to 3,33.

[0005]

In the above-mentioned core thin film magnetic head, the need for reducing the gap depth has increased due to recent trends in magnetic recording technology, but the following problems have occurred. That is, in order to reduce the gap depth, the area of the facing portion of the non-magnetic substrate had to be reduced gradually, but when the gap depth was about 1 to 4 μm, the mechanical strength of that portion was not sufficient.

As described above, the mechanical strength of the facing portion of the non-magnetic substrate is not sufficient, especially when the non-magnetic substrate and the magnetic thin film formed thereon, especially when the magnetic thin film is a metal magnetic thin film. This is because there is a large difference in the thermal expansion coefficient between the two, but since the non-magnetic substrates face each other in the magnetic gap part, the metal magnetic thin films sandwiched between the two can restrain each other to release the strain. Because there is no. Specifically, due to the heat history applied to the magnetic head during manufacturing or during use, peeling or cracking occurred due to internal stress in the shaded portion in FIG. 3, that is, in the magnetic gap portion at the tip of the head. Further, in the manufacturing process, a large force was applied to the head tip portion, that is, the magnetic gap portion by polishing the sliding surface to promote this. Further, not only the magnetic gap portion but also peeling due to internal stress frequently occurs over the entire inner peripheral surface of the winding window.

As a result, even if a currently known material having the highest saturation magnetic flux density is used, the core thin-film magnetic head has a problem that a magnetic field is not sufficiently generated at the head tip portion, resulting in a high recording density. It was an obstacle. In addition,
In this way, the magnetic head cannot generate a sufficient magnetic field not only in the above peeling, but even when these peeling does not occur, it is formed on the inner peripheral surface of the winding window by the effect of magnetostriction due to internal stress. It was also caused by the deterioration of the magnetic properties of the magnetic thin film.

[0008]

In order to achieve the above-mentioned object, the present invention comprises a pair of non-magnetic substrates having winding windows formed on opposing surfaces thereof and a metal magnetic thin film formed on the pair of non-magnetic substrates. A magnetic head comprising:
The metal magnetic thin film is formed on an inner peripheral surface including an apex portion of the winding window, and the metal magnetic thin film formed in the apex portion holds a gap material to form a magnetic gap. Provide the head.

The thickness of the metal magnetic thin film is 5 to 30.
The core thin film magnetic head is provided having a thickness of μm.

Furthermore, the core thin film magnetic head is provided in which the portion of the metal magnetic thin film in contact with the medium sliding surface is 30 to 45 degrees with respect to the medium sliding surface.

Furthermore, there is provided a core thin film magnetic head characterized in that an insulating protective layer made of a non-magnetic material is formed on the inner peripheral surface of the winding window on which the metal magnetic thin film is formed.

[0012]

According to the present invention, since the non-magnetic substrates do not face each other in the gap portion of the magnetic head having a very small gap depth, the materials having a large difference in thermal expansion coefficient are restrained in the magnetic gap portion. Therefore, it is possible to avoid the internal stress caused by the difference in thermal expansion during the manufacturing process.

Further, the thickness of the metal magnetic thin film is 5 to 30 μm.
Since the thickness is sufficiently thick as m, the mechanical strength can be maintained and magnetic saturation does not occur even if the magnetic gap is formed only by the metal magnetic thin film formed in the apex portion of the winding window.

Further, the portion of the metal magnetic thin film in contact with the medium sliding surface is 30 to 45 degrees with respect to the medium sliding surface.
Bridge part 3 including the magnetic gap part above the winding window shown inside
A mechanical strength of 0 can be sufficiently secured. Further, since the rigidity of the magnetic head as a whole can be ensured, the metal magnetic thin film will not be peeled off due to the stress caused by machining or the like during the manufacturing process after forming the metal magnetic thin film on the inner peripheral surface of the winding window.

Furthermore, since the insulating protective layer made of a non-magnetic material is formed on the inner peripheral surface of the winding window on which the metal magnetic thin film is formed, the metal magnetic thin film is protected from the outside air and the like, and the corrosion resistance of the magnetic head is improved. Will get better. Furthermore, this insulating layer has the effect of pressing the metal magnetic thin film of the winding window against the substrate side, and has the effect of further reducing film peeling of the metal magnetic thin film.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a side view of the core thin film magnetic head of one embodiment of the present invention as observed from the winding window side. In this magnetic head, a winding groove is formed on a pair of non-magnetic substrates 1 using a dicer or the like, and a non-magnetic thin film 2, FeTaN, FeAlSi, N
A metal magnetic film 3 such as iFe is formed by sputtering, vapor deposition or the like, then an insulating protective film 4 is applied, the gap material 5 is sandwiched by the metal magnetic film 3, and both substrates are formed using glass 6 or the like. The core thin film magnetic head is formed by fusion and integration.

A characteristic part of this magnetic head is that the magnetic gap is formed by the metal magnetic thin film 3 formed in the apex portion 31 of the winding window 7, as shown in an enlarged view in FIG. The magnetic gap is not formed by the metal magnetic thin film 3 formed on the opposing portions 32, 32 of the substrate above the apex portion of the winding window as in the conventional case shown in an enlarged scale in FIG. . In the present invention, as shown in FIG. 2, the metal magnetic thin film 3 serving as the magnetic core is protected by the insulating protection layer 4 formed on the metal magnetic film 3 arranged in the winding window. As shown in FIG. 4, when a strong insulating protective layer 6 is formed of glass or the like, the metal magnetic film 3 is sandwiched between the winding window portion of the non-magnetic substrate 1 and the inner wall which is the insulating protective layer of glass or the like. It becomes difficult for the magnetic head chip to be peeled off, and the mechanical strength of the magnetic head chip as a whole is improved.

A method of manufacturing this magnetic head will be described more specifically with reference to FIG. First, the winding groove 7 is formed by a dicer or the like along the longitudinal direction of the pair of blocks 36, 36 made of a non-magnetic material that is long in the plane of the paper (a). Then, 50 to 200 non-magnetic thin films 2 and 2 as a base layer for preventing film peeling of Cr, Ti or the like are formed on the surface of both blocks including the winding window.
Angstrom, FeTaN, FeTaNCu, Fe
Metal magnetic thin films 3 and 3 such as TaNAg are formed to 5 to 30 .mu.m, and insulating protection layers 4 and 4 made of SiO2 and Al2 O3 are formed to 1 to 5 .mu.m by sputtering or vapor deposition (b). Further, in a constant case, a material for the insulating protection layer 6 made of glass or the like is molded in the winding grooves 7 and 7 (c), and spaces 9 and 9 for winding are formed again by a dicer or the like (d). . Further, an undesired laminated portion is removed by polishing or the like (e), and a gap material made of SiO2, Al2O3 or the like is deposited on the opposing surfaces of both blocks by sputtering or vapor deposition to 500 to 5000 angstroms, and both blocks 36, 36 Are aligned by facing each other on the surface where the winding window is formed (g), and are integrated by cutting with a dicer or the like to the one-dot chain line in the figure to accurately obtain the gap depth, and then chip sliced as shown in FIG. Such a core thin film magnetic head is completed.

As the non-magnetic substrate used in this magnetic head, various ceramics and various glass substrates can be used. The gap material is SiO2 or Al2O3.
Alternatively, a laminated film of these and a certain metal material can be used.

Furthermore, when the angle of the metal magnetic thin film on the trailing side with respect to the medium sliding surface is set to 30 to 45 degrees, when a groove is formed in a long block by a dicer as shown in FIG. The long block 36 may be grooved depending on the shape of the diamond portion 20 of the blade on the blade supporting portion 21 of the blade of the dicer having a desired tip angle (b). By doing so, the metallic magnetic thin film formed by sputtering or the like is also formed on the medium at a desired angle of 30 to 45 degrees with respect to the medium. In this way, the angle of the metal magnetic thin film, and thus the substrate on which the metal magnetic thin film is formed, with respect to the sliding surface of the medium is set to 30 to 45 degrees, so that the chip strength and the like are secured as described above.

If the angle formed by the sliding surface of the metal magnetic thin film on the trailing side is 30 degrees or less, the structural strength of the upper part of the winding window is weakened, and if it is more than 45 degrees, the magnetic flux is short-circuited in the winding window part. Is not preferred.

[0022]

According to the above magnetic head structure, the magnetic strength of the magnetic gap portion of the core thin film magnetic head is sufficiently secured even with a very small gap depth, and the magnetic head has good magnetic characteristics. Can be realized.

[Brief description of drawings]

FIG. 1 is a side view of a core thin film magnetic head according to the present invention.

FIG. 2 is an enlarged side view of an apex part of a core thin film magnetic head according to the present invention.

FIG. 3 is an enlarged side view of an apex part of a core thin-film magnetic head according to the related art.

FIG. 4 is a side view of a core thin film magnetic head according to the present invention.

FIG. 5 is a manufacturing process diagram of a core thin-film magnetic head according to the present invention.

FIG. 6 is a groove processing state view with a dicer blade. (A) is an enlarged front view of the tip of the dicer blade. (B) is a sectional view showing a winding groove shape formed by the dicer blade shown in (a).

FIG. 7 is a side view of a core thin film magnetic head according to the prior art.

FIG. 8 is a manufacturing process diagram of a core thin-film magnetic head according to a conventional technique.

[Explanation of symbols]

 1 non-magnetic substrate 2 non-magnetic thin film 3 metal magnetic thin film 4 insulating protective layer 5 gap material 6 glass etc. 8 winding window

Claims (4)

[Claims] 1. A magnetic head comprising: a pair of non-magnetic substrates having winding windows formed on opposite surfaces thereof; and a magnetic core made of a metal magnetic thin film formed on the pair of non-magnetic substrates. A core thin film magnetic head, wherein the magnetic thin film is formed on an inner peripheral surface including an apex portion of the winding window, and the metal magnetic thin film formed in the apex portion sandwiches a gap material to form a magnetic gap. 2. The core thin film magnetic head according to claim 1, wherein the thickness of the metal magnetic thin film is 5 to 30 μm. 3. The core thin film magnetic head according to claim 1, wherein a portion of the metal magnetic thin film which contacts the medium sliding surface contacts the medium sliding surface at an angle of 30 to 45 degrees. 4. A core thin-film magnetic head, wherein an insulating protective layer made of a non-magnetic material is formed on the inner peripheral surface of the winding window on which the metal magnetic thin film is formed.