JPH02126409A - Production of magnetic head - Google Patents

Abstract

PURPOSE:To improve magnetic recording and reproducing characteristic by removing a working affected layer, which is formed on the surface of an oxide magnetic material by specular polishing, by electrolytic polishing after completing a specular polishing stage. CONSTITUTION:In an electrolytic polishing device, an inner container 23 filled with electrolyte 22 is housed in an outer container 21 filled with ice. A positive pole 24 consisting of a magnet is arranged with a slight space between the electrolyte 22 and itself on the electrolyte 22. Then, a negative pole 25 consisting of Pt plate is provided facing to the positive pole 24 in the electrolyte 22 and both poles 25 and 24 are connected to a power source 26. In the device, cores 1 and 2 made of the oxide magnetic material are attracted by the positive pole 24 and gap facing surfaces 11 and 12 are immersed in the electrolyte 22 so as to perform the electrolytic polishing. Thus, surface roughness is improved. The length of a gap 18 in the magnetic head completed by improving the surface roughness is stabilized. The magnetic recording and reproducing characteristic is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a magnetic head, which includes a step of mechanically mirror-polishing a block of oxide magnetic material.

[Conventional technology]

2. Description of the Related Art Conventionally, in order to perform high-density recording and reproduction, a magnetic head is known in which an alloy magnetic thin film is formed on the gap-opposed surface of a core made of a magnetic material. Hereinafter, the manufacturing procedure of such a magnetic head will be briefly explained. First, as shown in FIGS. 4 and 5, external winding grooves are formed in a pair of block-shaped cores 2 made of oxide magnetic material. 3 and 4 and glass-filled grooves 5 and 6 are formed, and an internal winding groove 7 is formed in one core 1.

Next, after each of the tape sliding surfaces 8 and 9 and the gap facing surfaces 11 and 12 of the core 2 are polished to a mirror finish, the gap facing surfaces 11 and 12 are polished as shown in FIGS. 6 and 7. Grooves 13, 13, . . . , 14, 14, . . . are formed to adjust the gap width in accordance with the track width in the magnetic recording medium.

Subsequently, after the vicinity of the surfaces of the gap facing surfaces 11 and 120 are etched, alloy magnetic thin films 15 and 16 are formed on the gap facing surfaces 11 and 12, as shown in FIGS. 8 and 9. Thereafter, although not shown, a gap material made of a non-magnetic material is adhered onto the alloy magnetic thin film 15 of one core 1.

Subsequently, as shown in FIG.
Both the cores 2 are joined by melting the glasses 17 with the glasses 12 facing each other. next,
As shown in FIG. 11, after the tape sliding surfaces 8 and 9 are given curvature, the core 2 is cut along the two-dot chain line in FIG. , a plurality of magnetic heads having gaps 18 between the tape sliding surfaces 8 and 9 are obtained.

[Problem to be solved by the invention]

By the way, according to the above manufacturing method, the tape sliding surface 8.
9 and the gap facing surfaces 11 and 12 are mirror polished by mechanical polishing on a tin surface plate. Therefore, during mirror polishing, a process-affected layer, that is, a non-magnetic portion, is generated in the core 2 made of an oxide magnetic material, resulting in a problem of deterioration of the magnetic recording and reproducing characteristics of the magnetic head.

Conventionally, in order to remove the process-affected layer, there has been a step of etching near the surfaces of the gap facing surfaces 11 and 12 after mirror polishing, which is also included in the above-mentioned manufacturing method. In such an etching process, it is difficult to completely remove the process-affected layer, and the surface roughness of the gap facing surfaces 11 and 12 after etching cannot be made to a good value.

[Means to solve the problem]

In order to solve the above-mentioned problems, a method for manufacturing a magnetic head according to the present invention includes a step of mechanically mirror polishing an oxide magnetic material, and after the mirror polishing step is finished, the method includes: This method is characterized in that the process-affected layer formed on the surface of the oxide magnetic material by mirror polishing is removed by electrolytic polishing.

[For production]

According to the above manufacturing method, electrolytic polishing is used to remove the process-affected layer that occurs during mirror polishing of oxide magnetic materials, so that the process-affected layer is completely removed and the magnetic head of the manufactured magnetic head is Recording and reproducing characteristics are improved. Furthermore, since the process-affected layer is removed by electropolishing, the surface roughness of the oxide magnetic material after electropolishing is also good.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 12.

The method for manufacturing a magnetic head according to the present invention is basically the same as the conventional example described above, and as shown in FIGS. 2, external winding grooves 3 and 4 and glass filling groove 5, respectively.
- 6 is formed, and an internal winding groove 7 is formed in one core 1.

Next, after each of the tape sliding surfaces 8 and 9 and the gap facing surfaces 11 and 12 of the COAT 2 are mechanically mirror-polished, the gap facing surfaces 11 and 12 are polished as shown in FIGS. 6 and 7. , grooves 13, 13... 14, 14... for adjusting the gap width in accordance with the track width in the magnetic recording medium.
is formed.

Subsequently, electrolytic polishing is applied to the vicinity of the surfaces of the gap facing surfaces 11 and 12 using an electrolytic polishing apparatus, which will be described later, to remove the process-affected layer formed on the gap facing surfaces 11 and 12 during mirror polishing. After that, as shown in FIGS. 8 and 9,
Alloy magnetic thin films 15 and 16 are formed on the gap facing surfaces 11 and 12.

Continuing, although not shown, the alloy magnetic thin film 1 of one core 1
A gap material made of a non-magnetic material is adhered on top of the gap material 5 .

Next, as shown in FIG.
Both cores 2 are joined by melting the glasses 17 while the two cores 2 are facing each other. continue,
As shown in FIG. 11, after the tape sliding surfaces 8 and 9 are given curvature, the core 2 is cut along the two-dot chain line in FIG. , a plurality of magnetic heads with a gap 18 between the tape sliding surfaces 8 and 9 are obtained.

The electropolishing apparatus will be described below. As shown in FIG. 1, the electrolytic polishing apparatus includes an outer container 21 filled with ice 20 and an inner container 23 filled with an electrolytic solution 22.

An anode 24 made of a magnet is arranged on the electrolytic solution 22 with a small distance between it and the electrolytic solution 22.
A cathode 25 made of a Pt plate is disposed inside 2 so as to face the anode 24 , and the anode 24 and the cathode 25 are connected to a power source 26 .

The electrolytic polishing apparatus described above adsorbs the core 2 made of an oxide magnetic material by the anode 24, and the gap facing surfaces 11 and 12
is immersed in an electrolytic solution 22 and subjected to electrolytic polishing, for example, under the conditions shown in Table 1 below.

When electrolytic polishing was performed under the conditions shown in Table 1, approximately 500 parts of the process-affected layer could be removed.

FIG. 2 shows the surface roughness of the gap facing surfaces 11 and 12 before electrolytic polishing. In FIG. 2, the horizontal axis is the direction along the surface, and the vertical axis is the height direction. As is clear from FIG. 2, the surface roughness of the gap facing surfaces 11 and 12 before electrolytic polishing is Rmax6
There are 0 people. Next, FIG. 3 shows the surface roughness of the gap facing surfaces 11 and 12 after electrolytic polishing under the conditions shown in Table 1. As is clear from FIG. 3, the surface roughness of the gap facing surfaces 11 and 12 after electrolytic polishing is Rmax 20 to 30, and the surface roughness of the gap facing surfaces 11 and 12 is also improved by electropolishing. There was found. By improving the surface roughness of the gap facing surfaces 11 and 12 in this manner, the gap length of the gap 18 in the completed magnetic head is stabilized.

The conditions for electrolytic polishing are not limited to the range shown in Table 1, and the electrolytic solution 22 is H(104 and C,)t.
, when using a mixture of OH, HClO4 is 10-5
0% by volume, cz Hs OH can be mixed at a ratio of approximately 50 to 90% by volume, and the applied voltage is 1O to
Approximately 30V, current density 0.1-1.0 mA/c
The temperature can be changed within the range of about 0 to 5°C. Furthermore, the above-mentioned HCl0. and C, H, OH
There is no problem in using other electrolytes.

〔Effect of the invention〕

As described above, the method for manufacturing a magnetic head according to the present invention includes:
In a method for manufacturing a magnetic head that includes a step of mechanically mirror-polishing an oxide magnetic material, after the mirror polishing step is completed, an altered layer formed on the surface of the oxide magnetic material by mirror polishing is removed using an electrolytic polishing method. This is a configuration in which the removal is performed by.

As a result, the process-altered layer that occurs during mirror polishing of oxide magnetic materials can be removed by electrolytic polishing.
The process-affected layer is completely removed, and the magnetic recording and reproducing characteristics of the manufactured magnetic head are improved. In addition, since the process-affected layer is removed by electrolytic polishing, the surface roughness of the oxide magnetic material after electropolishing is also good, and as a result, the gap length in the completed magnetic head is stabilized. become.

[Brief explanation of the drawing]

1 to 3 show examples of the present invention, in which FIG. 1 is a cross-sectional explanatory diagram of an electrolytic polishing apparatus, and FIG. 2 is a graph showing the surface roughness of the gap facing surface before electrolytic polishing. , FIG. 3 is a graph showing the surface roughness of the gap facing surface after electrolytic polishing, and FIGS. 4 to 12 are perspective views showing the manufacturing procedure of the magnetic head. 2.2 is a core (oxide magnetic material). Patent Applicant Sharp Co., Ltd. Figure 2+ U 1'Fil Figure Figure Figure Figure Figure Figure Figure Eight Figure Figure Figure 10

Claims (1)

[Claims] 1. In a method for manufacturing a magnetic head that includes a step of mechanically mirror-polishing an oxide magnetic material, after the mirror polishing step is completed, a process-altered layer formed on the surface of the oxide magnetic material by mirror polishing is electrolytically removed. A method of manufacturing a magnetic head, characterized in that removal is performed by a polishing method.