JPH01165007A - Magnetic head - Google Patents

Abstract

PURPOSE:To enhance the accuracy of a magnetic gap and to reduce a cost by disposing a winding hole in a core half body consisting of a magnetic material, overlapping the gap member of a prescribed film thickness and a soft magnetic film constituting a closed magnetic path on a gap face and constituting a magnetic circuit. CONSTITUTION:The gap is formed not by a laminating system but by overlapping the films to enhance a gap length accuracy and improve a yield and the magnetic circuit of a magnetic head is formed by overlapping the gap member 3 of the prescribed film thickness and the soft magnetic film 2 on the gap face of the core half body 1 on which the winding hole 5 is disposed. Namely, after a track width regulating groove is disposed on the core half body 1, a nonmagnetic material (glass) 6 is buried, a gap forming face side is buried by a nonmagnetic material 4 with the winding hole 5 left and the gap member 3 and the soft magnetic film 2 are overlapped on the gap forming face of the core half body 1 which is substantially plane.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head suitable for high-density VTRs, DATs, FDs, etc.

BACKGROUND OF THE INVENTION Conventionally, ferrite bulk magnetic materials have been used as magnetic head materials for VTRs. In manufacturing a magnetic head using a bulk material such as ferrite, a magnetic gear is formed by laminating a pair of core halves that have been subjected to shape processing such as track processing and first winding groove processing to the above-mentioned material. For this purpose, the gap forming surfaces of the pair of core halves are polished with high accuracy, a gap member having a desired thickness is formed by a spattering method, 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. etc. are not essentially different from conventional ferrite heads.

In recent years, with the development of high-density magnetic recording, the use of r-Fe203, metal magnetic powder, barium ferrite, and the like as recording media is being considered to meet the demand for improved recording density. In response to changes in recording media, there is a growing demand for narrow gap magnetic heads using metallic magnetic materials. Fe-Aj, a generic name for metallic magnetic materials! -S
Magnetic heads using crystalline magnetic alloys such as i-alloy (referred to as sendust) and Ni-Fe alloy (permalloy), or amorphous alloys generally have a higher saturation magnetic flux density than ferrite materials, and have a higher sliding resistance. Although it has an excellent feature of low noise, it has the drawback of being difficult to process. In order to obtain a highly accurate gap length using the conventional bonding gap forming method, not only for metal magnetic materials but also for ferrite, it is necessary to not only improve the finishing accuracy of the gap forming surface but also to prevent dissimilar materials such as glass. It is necessary to reduce the warpage of the core half due to differences in thermal expansion with the material, distortion due to processing, etc., and advanced polishing techniques are required. In particular, as the gap length becomes smaller, desired head characteristics cannot be stably obtained due to variations in the gap length, resulting in lower yields.

Problems to be Solved by the Invention Narrowing the gap is essential in a magnetic head for high-density magnetic recording. For heads with such narrow gap lengths, the heads with the conventional structure and manufacturing method described above,
The process of forming the magnetic gap is the process that reduces the yield the most, and the low yield of gap accuracy is a major cause of high costs.

Means for Solving the Problems The present invention provides a winding hole in a core half made of a magnetic material, and overlies a gap member with a predetermined thickness and a soft magnetic thin film constituting a closed magnetic circuit on the gap surface. The present invention attempts to solve the above-mentioned problems by forming a magnetic head that constitutes a magnetic circuit.

Functional gap formation is not dependent on the conventional method of lamination.
Since this method is used to form layers III overlapping each other, a head with high gap length accuracy and good yield can be manufactured at low cost.

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 structure of a magnetic head of the present invention. The magnetic circuit of this magnetic head consists of a core half 1 provided with a winding hole 5 and a soft magnetic thin film 1) 92 with a gap member 3 in between. The non-magnetic material 6 is made by forming a groove on the core half l to regulate the track width and then embedding the non-magnetic material 6 therein, and the winding groove 8 is formed by leaving the winding hole 5 on the gap forming surface side. A gap member, a soft magnetic material i[, is formed in an overlapping manner on the gap forming surface of the core half, which is covered with a non-magnetic material 4 and is substantially flat.

A specific method of manufacturing this magnetic head will be described below in detail with reference to the drawings.

FIG. 2 is a process diagram showing the method for manufacturing the magnetic head of the present invention. As shown in FIG. 2+al, a track mold groove 7n for regulating the track width is formed in the sendust bulk material 1 having a predetermined size to become the core half. Then the second
The glass 6n is placed in the track mold groove as shown in Figure (C1)
After heating and melting at 750°C and filling, the surface is ground.

Furthermore, after processing the winding groove 8 shown in FIG. 2 +di, a non-magnetic material 4 ( In this embodiment, the gap forming surface 9 is polished. Next, as shown in FIG.
After forming a gap member 3 of Cr (3 μm) by sputtering, a soft magnetic thin film (in this example, an alloy IS mainly composed of Fe-Al-Si was used) 2 constituting one magnetic circuit was formed by sputtering. Formed overlying the gap member. The magnetic head block 10 is manufactured in this manner. Furthermore, as shown in FIG. ) to obtain the magnetic head block 13 shown in FIG. 2(h).
By cutting at the positions indicated by broken lines, the magnetic head shown in FIG. 1 is obtained.

The magnetic head manufactured as described above requires a small number of steps, and in particular, the gap forming step is formed by stacking thin films instead of the conventional bonding process, so it has an extremely high yield and can be manufactured at low cost. can. Valinium ferrite also has good recording properties because it uses a metal magnetic alloy as the core. It also showed excellent properties for high-density recording media such as metal magnetic powder.

Example 2 In place of the soft magnetic thin film 2 of Example 1, a magnetic head was fabricated using an amorphous alloy thin film containing Go as the main component in the same process as Example 1. In this example, an amorphous alloy thin film was used. Considering the heat resistance of the thin film, the heating temperature when heating and melting the glass was set to about 500° C. or less. The magnetic properties and reliability of the thus obtained magnetic head were as good as in Example 1.

Example 3 Fa-AI-81 used as soft magnetic thin film 2 in Example 1
Instead of alloy thin film, alloy f whose main component is F'5-Ni
ill! A magnetic head was manufactured using the same steps as in Example 1. The magnetic properties and reliability of the thus obtained magnetic head were as good as in Example 1.

Example 4 In place of the alloy thin film mainly composed of Fe-Ajl-3L used in Examples 1 and 2.3, the amorphous alloy thin film mainly composed of Co, and the alloy thin film mainly composed of Fe-NL, soft A composite magnetic head was fabricated in the same manner as in Example 1 using an Fe-C (13 at%) compound thin film as the magnetic thin film 2. The obtained magnetic head was as good as Examples 1, 2.3. In addition, N (7 at%) is used as the soft magnetic thin film 2.
.

Magnetic heads manufactured using compound thin films containing P (10 at %) were also good as in the above-mentioned examples.

Effects of the Invention As described above, the present invention includes forming a gap member having a predetermined film thickness and a soft magnetic thin film constituting a closed magnetic path on the gap forming surface of a core half provided with a winding hole. Because it is a magnetic head that can form a magnetic gap with high precision,
A magnetic head with good magnetic properties and high reliability can be manufactured at low cost and with good processing yield.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of the composite magnetic head of the present invention;
FIG. 2 is a process diagram illustrating a method for manufacturing a head in an embodiment of the present invention. 1... Core half, 2... Soft magnetic thin film,
3... Gap member, 4... Non-magnetic material, 5... @ wire included, 6.6n... Trunk mold glass, 7n... ...Track groove, 8
...@line groove, 9...gap forming surface,
10...Magnetic head block 1)1)...
...Nonmagnetic material, 12...Adhesive, 13...
...Magnetic head block ■. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 1: 3 years old Figure 2

Claims (5)

[Claims] (1) A magnetic head characterized in that a core half made of a magnetic material is provided with a winding hole, and a predetermined gap member and a soft magnetic thin film forming a closed magnetic path are stacked on the gap surface. (2) A patent characterized in that the winding hole provided in the core half made of magnetic material is embedded with a non-magnetic material so as to leave the winding hole in the winding groove and cover the gap forming surface. A magnetic head according to claim (1). (3) The magnetic head according to claim (1), wherein a metal material such as Cr or Mo is used as the gap member. (4) The soft magnetic thin film is characterized in that it is either an alloy thin film containing Fe-Al-Si as a main component, an alloy thin film containing Fe-Ni as a main component, or an amorphous alloy thin film containing Co as a main component. A magnetic head according to claim (1). (5) The magnetic head according to claim (1), wherein the soft magnetic thin film is a compound thin film mainly composed of Fe and containing at least one of C, N, and P.