JPH04149808A - Magnetic head and production thereof - Google Patents

Abstract

PURPOSE:To assure flatness and to enhance magnetic efficiency as well as to stably obtain the magnetic head having good quality by superposing soft magnetic material powder and nonmagnetic material powder and subjecting these powders in integral compression molding and calcining to form the half body of a composite substrate. CONSTITUTION:Blank materials are formed of soft magnetic ferrite 10 and nonmagnetic ceramics 20 adjusted to have the calcination conditions and coefft. of thermal expansion equal to each other. These blank materials are alternately superposed and are subjected to integral compression molding to form the substrate having the composite structure. Metallic thin films 40a to 40c are laminated by inserting Nonmagnetic thin films 30a, 30b between a pair of such composite substrate half bodies. The plural composite substrates are superposed and adhered in the lamination direction of the thin films 40a to 40c to produce the core half body block of a rectangular parallelepiped. This block is cut a prescribed intervals and in the face direction, by which the columnar core half body blocks are obtd. The sufficient flatness of the composite substrate half bodies is then assured and the magnetic head having high magnetic efficiency and good quality is stably obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a magnetic head used for magnetic recording and reproduction and a method of manufacturing the same.

(Prior Art) Ferrite heads and bulk metal heads have conventionally been used as magnetic heads used for magnetic recording and reproduction. However, in recent years, the following metal laminate heads have been proposed in order to cope with the adoption of metal tapes with high coercive force and the widening of recording signal bands with the trend toward higher density recording.

FIG. 9 is a perspective view showing the structure of a conventional metal laminate head. As shown in the figure, this head 1 has a metal magnetic thin film 4 as 4 b between a pair of composite substrate halves (2a and 2b, 3a and 3b).

Metal magnetic thin films 4c, 4d, 4e are formed between a magnetic head core half 6a formed by alternately stacking and sandwiching magnetic films 4c and magnetic films 5a and 5b, and a pair of composite substrate halves (2c and 2d, 3C and 3d). and a magnetic head core half body 6b formed by sandwiching and stacking insulating films 5C% 5d alternately, and are joined by a crystallized glass 8 with an operating gap 7, and then wound in a winding groove 9 provided at the joint. line (not shown)
It is constructed by winding the .

In addition, in this metal laminating head 1, one (back side) board parts 2a, 2 constituting each composite board half
b, 2c, and 2d are made of a magnetic material such as soft magnetic ferrite, and the other (front side) board parts 3a, 3b, and 3c are
, 3d are made of non-magnetic material such as non-magnetic ceramics, and each board component is bonded using crystallized glass. This effectively lowers the magnetic resistance of the head core and pack gap, and improves the magnetic efficiency of the head 1. The method for manufacturing this magnetic head is disclosed in Japanese Patent Application No. 80-278797.

However, in such a magnetic head, a problem has arisen in that it is difficult to ensure sufficient flatness at the joint due to the difference in coefficient of thermal expansion between the substrate and the crystallized glass that constitute the composite substrate halves.

Therefore, a method of bonding each substrate while fixing the positional relationship has been considered, but in this case, there was a risk that the crystallized glass would break due to the generation of internal stress. In addition, when bonding substrates using crystallized glass, there is a risk that deviations may occur during polishing of the substrates due to insufficient bonding strength.

(Problem to be solved by the invention) As described above, in conventional magnetic heads, it is difficult to ensure sufficient flatness of the composite substrate, and this is considered to be one of the major causes of quality deterioration. .

The present invention is intended to solve these problems, and provides a magnetic head and method for manufacturing the same, which can ensure sufficient flatness in the composite substrate half and stably obtain a high-quality magnetic head with high magnetic efficiency. The purpose is to provide

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the magnetic head of the present invention has the following features:
It is characterized by having a pair of core halves formed by sandwiching a metal magnetic thin film between a pair of composite substrate halves formed by integrally molding and firing a soft magnetic material and a nonmagnetic material.

Further, in order to achieve the above object, the method for manufacturing a magnetic head of the present invention includes a method for manufacturing a composite substrate half of a magnetic head consisting of a soft magnetic material and a non-magnetic material. The process includes a step of stacking and integrally compression-molding the powders, and a step of firing the composite substrate obtained by this step.

(Function) In the magnetic head and the manufacturing method thereof of the present invention, since the composite substrate half is produced by stacking soft magnetic powder and non-magnetic powder and integrally compression molding and firing, sufficient strength is obtained in the composite substrate half. Flatness can be ensured, and a high-quality magnetic head with high magnetic efficiency can be stably obtained.

(Example) Embodiments of the present invention will be briefly described below with reference to the drawings.

FIG. 1 is a diagram showing a manufacturing process of a composite substrate in a metal laminate head according to an embodiment of the present invention.

First, the soft magnetic ferrite 1o and the non-magnetic ceramic 20, which were adjusted to have the same firing conditions, shrinkage rate, thermal expansion coefficient, etc., were weighed, mixed (wet), dehydrated, dried, soot baked, pulverized (wet), dehydrated, The material is prepared through each step of drying (steps S1 and S2), and a binder is mixed and granulated (steps S3 and S4).

Thereafter, layers of soft magnetic ferrite powder and layers of non-magnetic ceramic powder are alternately stacked and integrally compressed in a mold to form a substrate with a composite structure (step S5).

Next, this integrally molded composite substrate is co-fired (step S6) and polished to a predetermined dimensional accuracy (step S7).

FIG. 2 shows a composite substrate produced through the above steps.

In addition, in the firing process of step S6, if there is a difference in firing conditions between the soft magnetic ferrite 10 and the non-magnetic ceramic 20, priority is given to the conditions for the soft magnetic ferrite 10, which have a large influence on the performance of the head.

In addition, soft magnetic ferrite 10 and non-magnetic ceramic 20
If you want to accurately form the interface between the non-magnetic ceramics 20 and
5 a s S 6 a ), this may be used for integral molding with the soft magnetic ferrite 10. however,
In this case, non-magnetic ceramics 2 with a relatively high firing temperature are used.
It is desirable to select 0.

In addition, when selecting general materials, soft magnetic ferrite 1
0 is M n -Z, which has high magnetic permeability in the normal usage band.
n ferrite, Z as the non-magnetic ceramic 20
It is desirable to use n-ferrite.

Next, a method for manufacturing a metal laminate head using the composite substrate manufactured as described above will be described.

First, as shown in FIG. 2, the composite substrate is cut along the dotted line in the figure at equal intervals in a direction perpendicular to the bonding surface between the soft magnetic ferrite 10 and the non-magnetic ceramic 20. As a result, a composite substrate as shown in FIG. 3 is obtained.

Next, after polishing both sides of this composite substrate, as shown in FIG.
A metal magnetic thin film 40as 40b, 40c with a non-magnetic thin film 30g, 30b made of 5i02 etc. sandwiched therebetween by a sputtering method is formed on one surface perpendicular to the bonding surface with the magnetic tape with a width corresponding to the track width of the magnetic tape. Stack.

Thereafter, as shown in FIG. 5, a plurality of these composite substrates are stacked and bonded in the stacking direction of the metal magnetic thin films 40as 40b, 40c to produce a rectangular parallelepiped core half block.

Next, this core half block is attached to the joint surface of the soft magnetic ferrite 10 and the non-magnetic ceramic 20 (C-C- in FIG.
(along the plane). FIG. 6 shows one of the core half blocks cut out as a result.

Next, this core half block is coated with soft magnetic ferrite 10.
At equal intervals along a plane (a plane along C-C- in FIG. 6) that is orthogonal to the bonding surface between disconnect. As a result, a columnar core half block is cut out.

Thereafter, as shown in FIG. 7, the core half block is machined with winding grooves, and after polishing the surface facing the gap, the winding grooves are machined, in the same manner as in the commonly known manufacturing method of magnetic heads. A core half block without a gap and a gap spacer are sandwiched between the gap facing surfaces and are bonded using crystallized glass, and the bonded core block is coated with a metal magnetic thin film 40a, 4.
0 b, 40 c and parallel to the metal magnetic thin films 40a, 40b, 40c and the nonmagnetic thin films 30a, 30.
Each head core is obtained by cutting along a suitable plane (a plane along C-C- in FIG. 6) except for b.

Then, a tape sliding surface is formed on each head core to obtain a magnetic head chip as shown in FIG.

Thereafter, this magnetic head is fixed to a base, and a predetermined magnetic head is completed through winding, molding, etc.

Thus, according to this embodiment, the soft magnetic ferrite powder 10 and the non-magnetic ceramic powder 20 are formed by stacking the soft magnetic ferrite powder and the non-magnetic ceramic powder alternately in a mold, integrally compression molding them, and firing them simultaneously. An integrated composite substrate can be obtained by strongly bonding by diffusion/fixation reaction, and as a result, a high-quality magnetic head with excellent flatness and polishing properties at the bonded portion can be obtained.

[Effects of the Invention] As explained above, according to the magnetic head and the manufacturing method thereof of the present invention, it is possible to ensure sufficient flatness in the composite substrate half, and to stably obtain a high-quality magnetic head with high magnetic efficiency. becomes possible.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the manufacturing process of a composite substrate in a metal laminate head according to an embodiment of the present invention, and FIGS. FIG. 9 is a perspective view showing the structure of a conventional metal laminate head. 10...Soft magnetic ferrite, 2o...Nonmagnetic ceramics, 30a, 30b-=nonmagnetic thin film, 40a240
b, 40c...Metal magnetic thin film. Applicant: Toshiba Corporation Toshiba Audio/Video Engineering Corporation

Claims (3)

[Claims] (1) A magnetic head characterized by having a pair of core halves formed by sandwiching a metal magnetic thin film between a pair of composite substrate halves formed by integrally molding and firing a soft magnetic material and a nonmagnetic material. . (2) A method for manufacturing a composite substrate half of a magnetic head made of a soft magnetic material and a non-magnetic material, including the step of stacking and integrally compression molding the soft magnetic material powder and the non-magnetic material powder; 1. A method of manufacturing a magnetic head, comprising the step of firing a composite substrate obtained by the step. (3) A step of integrally molding a soft magnetic powder and a non-magnetic powder or a substrate after molding and firing the same, a step of firing a composite substrate integrally molded by this step, and a fired composite substrate. dividing in a direction perpendicular to the joint surface of the soft magnetic material and the non-magnetic material, and perpendicular to the joint surface of the soft magnetic material and the non-magnetic material on the divided composite substrate. a step of laminating a metal magnetic thin film on one surface; a step of stacking and bonding a plurality of composite substrates on which the metal magnetic thin films are laminated in the lamination direction of the metal magnetic thin films to produce a rectangular parallelepiped core half block; A rectangular parallelepiped core half block is divided along a joining surface between the soft magnetic material and the non-magnetic material, and also along a surface perpendicular to the joining surface and perpendicular to the surface of the metal magnetic thin film. a step of manufacturing a columnar core half block from the columnar core half block; a step of manufacturing a magnetic head core block having a winding groove and a core gap from the columnar core half block; A method for manufacturing a magnetic head, comprising the step of: fabricating a magnetic head core by dividing the metal magnetic thin film at a position parallel to the plane of the magnetic head.