JPH0191310A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To manufacture a head, which is highly precise in a gap length and is free of track dislocation, at a low price by performing working to regulate a track after the gap member of a prescribed film thickness and a soft magnetic film are piled and formed on the gap forming surface of a core half body. CONSTITUTION:After a first soft magnetic thin film 21 is formed on the core half body 1, and a winding groove 8 is worked, non-magentic material 4 is embedded except at a winding hole 5, and the gap forming surface is ground. Next, after the gap member 3 of a prescribed thickness is formed by sputtering, the second soft magnetic thin film 2 to constitute a magnetic circuit of one side is formed as being piled on the gap member 3, by the sputtering. Next, after a track mold groove is worked, and is filed with glass, a a holding member block is bonded with the glass, and is cut, and a head chip is obtained. Thus, the head highly precise in the gap length and free of the track dislocation is obtained at a low price.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a magnetic head suitable for a VTR or a high-density magnetic recording/reproducing device such as a digital audio device.

BACKGROUND OF THE INVENTION Conventionally, bulk magnetic materials such as ferrite or sendust have been used in magnetic heads used in VTRs, digital audio, and the like. The magnetic gap of a head made of such a material is formed by bonding together a pair of core halves that have been subjected to shape processing such as track processing and winding groove processing to the above-mentioned material.

For this purpose, the gap forming surfaces of the pair of core halves are thoroughly polished, a gap member having a desired thickness is formed by sputtering, etc., and then glass or the like is used as an adhesive and melted by heating. In addition, in recording and reproducing systems using high coercive force media such as metal magnetic powder, heads made of composite materials are also used that improve recording efficiency by forming a metal magnetic thin film near the magnetic gap, but the manufacturing method The shape, etc. of the wood is not different from that of conventional ferrite heads.

In recent years, with the development of high-density magnetic recording, there has been a demand for magnetic heads with extremely small magnetic gap lengths. For example, in digital audio tape (DAT), a thickness of 0.3 μm or less is required. In the conventional gap forming method by bonding, in order to obtain a precise gap length, it is necessary to check not only the finishing accuracy of the gap forming surface but also the thermal expansion difference between different materials such as glass, distortion due to processing, etc. It is necessary to minimize the warpage of the core half, which requires advanced polishing technology.However, there is a limit to such technology, and for narrower gap lengths, it is difficult to reduce the gap length. Due to the variations, desired head characteristics cannot be stably obtained, resulting in a decrease in yield.

Problems to be Solved by the Invention In a magnetic head for high-density magnetic recording, narrowing the gap is essential. For heads with such narrow gap lengths, with the above-mentioned conventional structure and manufacturing method, the process of forming the magnetic gap is the process that reduces the yield the most, and not only the gap accuracy but also the narrow track Tracks generated during bonding are also a cause of lower yields in heads. Furthermore, in a recording/reproducing system using a high coercive force medium such as metal magnetic powder, it is necessary to form a soft magnetic thin film with a high saturation magnetic flux density near the magnetic gap to improve recording efficiency.

Means for Solving the Problems The present invention solves the above problems by providing a core mainly composed of an oxide magnetic material, with a first soft magnetic thin film formed near the gear hub, and provided with a winding hole. A solution was achieved by forming a gap member of a predetermined thickness and a soft magnetic thin film constituting the other magnetic circuit on the gap forming surface of the half body, and then performing processing to regulate the track. It is something that we try to do.

Forming working gears without relying on the conventional method of lamination,
Since this method uses a method of forming thin films in layers, the gap length accuracy is high and the characteristics are stable.Also, since track processing is performed after forming the second soft magnetic thin film, it is possible to produce a magnetic head with no track misalignment. It is good and can be manufactured at low cost. Furthermore, since the vicinity of the gap can be made of a soft magnetic thin film with a high saturation magnetic flux density, the recording efficiency is high and it can be used for high coercive force media.

EXAMPLE Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

Embodiment 1 FIG. 1 is a perspective view showing the manufacture of a core chip of a magnetic head by the manufacturing method of the present invention. The magnetic circuit consists of a core half 1 provided with a winding hole 5, a first soft magnetic thin film 21 formed near the gap, and a second soft magnetic thin film 2 with a gap member 3 sandwiched therebetween. . Moreover, the winding groove 8 is
A gap member, No. 20 soft Ci', is placed on the gap forming surface of the core half, which is embedded with a non-magnetic material 4 so as to leave the winding hole 5 and cover the gap forming surface side, and is substantially flat. The bacterial membranes are formed by overlapping each other. Furthermore, since the track processing is performed after the formation of the second soft magnetic thin film, no track deviation occurs in principle.

FIG. 2 is a process diagram showing the method for manufacturing the magnetic head of the present invention. As shown in FIG. 2(a), a first soft magnetic thin film 21 (in this example, a Fe-Al-Si alloy thin film is formed by a sputtering method on a ferrite bulk material 1 having a predetermined size to become a core half). form). At this time, etching the sputtered surface of the ferrite bulk material to form a predetermined angle with the gap surface is effective for avoiding the influence of the pseudo gap, but this is omitted in this embodiment. Furthermore, after machining the winding groove 8 shown in FIG. 2 (bl), a non-magnetic material is added so as to leave the winding hole 5 in the winding groove and cover the gap forming surface side, as shown in FIG. 2 (C). After embedding the material 4 (glass was heated and melted and used in this example), the gap forming surface 9 is polished (C1°). After forming 5iO7 as the gap member 3 with a thickness of .3 μm) by sputtering, a soft magnetic thin film (in this example, an alloy thin film mainly composed of Fe-Al-3t was used) 2 constituting one of the magnetic circuits was sputtered. FIG. 2 (dl) shows a ring formed over the gap member. FIG. 2 (e) shows a track mold groove 7n that defines the track width is further processed.

Next, glass 6n is heated and melted at 750° C. and filled into the track mold groove, and the surface is then ground.

The magnetic hesodopron 10 is manufactured in this way.

Furthermore, as shown in FIG. 2(g), after adhering a non-magnetic holding material block 1) to the magnetic hend block (in this example, glass was heated and melted at 500°C as the adhesive material). The magnetic head chip shown in FIG. 1 is obtained by cutting at the position shown by the broken line in FIG. 2(h). The thus obtained magnetic hendochisop is further bonded to a base and wound with a wire for practical use.

The magnetic head manufactured as described above has good gear accuracy due to the method of forming thin films one on top of the other, and there is no track deviation, so it can be manufactured at a high yield and at low cost. Furthermore, since a metal magnetic alloy is used in the vicinity of the gap, the recording characteristics are good, and the recording characteristics are also excellent for high-density recording media such as Ba ferrite and metal magnetic powder.

Example 2 Instead of the alloy thin film mainly composed of Fe-Al-Si used in Example 1, an amorphous alloy thin film mainly composed of Co and an amorphous alloy thin film mainly composed of Fe-Ni were used as the first and second soft magnetic thin films. A similar magnetic head can be obtained using any of the alloy thin films. When using an amorphous alloy thin film mainly composed of Co as a soft magnetic thin film, in order to avoid crystallization,
Glass with a working temperature of 500° C. or lower was used. The magnetic head manufactured in the same manner as in Example 1 except for the above was as good as in Example 1.

Example 3 An alloy thin film mainly composed of Fe-Al-Si was used as the first soft magnetic thin film as in Example 1, and the second soft magnetic thin film II!
A magnetic head was fabricated using the same steps as in Example 1 using an Fe-C (8 at %) compound thin film as Example 2. The obtained magnetic head was as good as Example 1.2. In addition, as the second soft magnetic thin film 2, N (7 at%), P
Magnetic heads manufactured using compound thin films containing (10 at %) were also good as in the above-mentioned examples.

Effects of the Invention As described above, the method for manufacturing a magnetic head of the present invention includes a core mainly composed of an oxide magnetic material, a first soft magnetic thin film formed near the gap, and a core provided with a winding hole. On the gap forming surface of the half body, thin films are stacked in the order of the gap member and the soft magnetic thin film to form the gap, and then track processing is performed, so gap accuracy is significantly improved compared to the conventional bonding method. Moreover, since there is no track deviation, the characteristics are stable, and the manufacturing process is simple, so it can be manufactured at a high yield, and the manufacturing cost of the head can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of the magnetic head of the present invention, and FIG.
The drawings are process diagrams illustrating a method for manufacturing a head in an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Core half, 2...Second soft magnetic thin film, 3...Gap member, 4...Nonmagnetic material, 5... ... Winding hole, 6 ... Track mold glass, 7 ... Track groove, 8.
... Winding groove, 9 ... Gap forming surface, 1
0...Magnetic hend block, 1)...
Holding material block, 21...first soft magnetic thin film. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 1 Figure 3 Map members Figure 2

Claims (4)

[Claims] (1) A first soft magnetic thin film mainly composed of oxide magnetic material is formed near the gap, and a gap member with a predetermined film thickness is placed on the gap forming surface of the core half where the winding hole is provided. , and a second soft magnetic thin film constituting the other magnetic circuit, and then processing to regulate the track width is performed. (2) The winding hole provided in the core half is formed by filling a non-magnetic material so as to leave the winding hole in the winding groove and cover the gap forming surface side. A method for manufacturing a magnetic head according to scope (1). (3) Either an amorphous alloy thin film mainly composed of Co, an alloy thin film mainly composed of Fe-Al-Si, or an alloy thin film mainly composed of Fe-Ni for the first or second soft magnetic film. A method of manufacturing a magnetic head according to claim 1 or 2, characterized in that a method is used. (4) Claim (1) characterized in that the first or second soft magnetic thin film is a compound thin film mainly composed of Fe and containing at least one of C, N, and P. 3. The method for manufacturing a magnetic head according to any one of item 1 and item 2.