JPH0349012A - Manufacture of magnetic head - Google Patents

Abstract

PURPOSE:To stick a protective plate with high accuracy by pouring melted glass by providing a thin film pattern which becomes a height positioning pad, and setting a gap between the protective plate and a magnetic head pattern setting the thin film pattern as a reference plane. CONSTITUTION:In the manufacturing process of a 2-ch thin film magnetic head for electronic still camera, a height positioning pad pattern 2 is set so as to remain in all pattern etching processes. As a result, the pattern 2 is formed higher than the coil elevation part 14 of an upper electrode 1. Next, a processed head substrate 7 is butted with the protective plate 8. At this time, the protective plate 8 is prevented directly coming in contact with a head pattern 3 with the pattern 2, which enables the glass to be easily poured. As a result, the dispersion of the substrate 7 and the protective plate 8 on the medium sliding plane 12 of a head can be remarkably reduced.

Description

[Detailed Description of the Invention] This invention relates to a method for manufacturing an inductive thin film magnetic head mainly used for magnetic recording (writing), and in particular to a method for welding a protective substrate onto a magnetic head pattern. The present invention relates to a protective substrate welding process for a thin film magnetic head that requires the following steps.

In the conventional magnetic head of the type in which recording and reproducing are performed by contacting the magnetic head with the recording medium, wear of the sliding surface of the magnetic head due to the magnetic head sliding in contact with the medium for a long period of time becomes a problem. Generally, a thin film magnetic head has a structure in which a coil conductor 6 is disposed on a lower magnetic pole 4 via an insulating layer 5, and an upper magnetic pole 1 is formed to interlink with the coil conductor 6, as shown in FIG. The upper and lower magnetic poles 1.4 are often made of a metal material such as FeAlSi, FlfFe, or an amorphous alloy. For this reason, the upper and lower magnetic poles 1.4
tends to cause uneven wear, resulting in deterioration of the recording and reproducing characteristics of the magnetic head. As a countermeasure, a ceramic substrate with good wear resistance is installed on the head protection plate 8 as shown in Figure 2.
Generally, the thin film head pattern 3 is bonded to the thin film head pattern 3 using an adhesive 9 to improve wear resistance. Note that the adhesives used here can be roughly divided into organic adhesives and inorganic adhesives.

The organic adhesive layer 9 that appears on the head sliding surface 12 eliminates the unevenness and makes the adhesive strong enough.
becomes thicker. When an organic adhesive is used, its abrasion characteristics are generally poor, so when the magnetic head runs over the medium to perform recording and reproduction, the adhesive layer 9 near the medium sliding surface 12 of the magnetic head is damaged. However, it is most likely to cause uneven wear. As a result, a so-called spacing loss occurs, and the recording and reproducing characteristics of the magnetic head deteriorate.

In order to solve this problem, a thick layer of protective filO (for example, alumina) made of an inorganic material with good wear characteristics is formed on the magnetic head pattern 3 so that the adhesive layer can be made thinner, as shown in FIG. 6(a). To form a film.

Next, a sixth
As shown in Figure (b), this protective film is
A method has been considered in which the organic adhesive layer 10a is bonded with an organic adhesive after polishing with a polishing agent so that the size of the organic adhesive layer 10a becomes smaller during bonding. However, using this manufacturing method has the disadvantage that the operations described above are long and complicated, and the process is extremely long.

On the other hand, when bonding using an inorganic adhesive (especially glass), take into account that the magnetic properties of the thin film magnetic head deteriorate when exposed to high temperatures. Needs to be glued.

When bonding by this method, in order to bond glass with sufficient strength, a method has been considered in which a film is formed in advance on the entire surface of the bonding surface by coating or sputtering. However, in the former method, after applying powdered glass as a slurry, air bubbles are generated inside the glass during heat treatment to evaporate the medium and melt the glass, resulting in holes in the sliding surface 12 of the finished magnetic head. I often end up. Furthermore, the latter method, sputtering, is disadvantageous in terms of cost because it requires a long process, similar to the method of forming a protective film of an inorganic material.

Therefore, in order to be cost-effective and to improve wear resistance, the most practical method is to pour glass between the magnetic head pattern 3 and the protection plate 8. However, when the substrate on which the thin-film magnetic head is formed and the protective plate are directly brought into contact with each other and glass is poured into the gap 13 between the two, the magnetic head pattern becomes thickest at the overlapping portion 14 of the coil of the upper magnetic pole 1. Therefore, the gap 13 becomes narrowest at the corresponding portion, increasing fluid resistance and making it difficult for glass to flow into the gap 13. As a result, air bubbles remain in the area 15 after this part, making it difficult to obtain sufficient strength.For this reason, in the past, the thickness of the magnetic head was made as thin as possible; Since it is necessary to create a gap between the head pattern and the protection plate for the glass to flow into, a thin ceramic plate is used as a spacer.In other words, a spacer 16 is placed between the protection plate 8 and the substrate 7 as shown in FIG. There was a gap forming.

However, with this method, the cost of processing the spacer thin is high, and in terms of accuracy, the gap is different between the vicinity 17 where the spacer is placed and the central part 18 of the substrate 7, making it difficult to accurately make the gap between the individual heads. The protection plate 8 could not be fixed.

In order to solve the above-mentioned problem, this invention in No. 2 provides a thin film pattern that is thicker than the upper magnetic pole and serves as a height positioning pad, and uses this thin film pattern as a reference plane to connect the protective plate and the magnetic head pattern. The technical means is to set a gap between the glass and weld the glass by pouring the molten glass into the gap.

According to this invention, by forming a height positioning pad with a thin film pattern, a spacer is located near each magnetic head, and the gap between the magnetic head pattern and the protective plate is There is no variation between heads.

Therefore, it is possible to accurately form a thinner gap than with conventional ceramic spacers.

Asthma Prevention The present invention will be explained below using an example in which the present invention is implemented in a head pattern of a 2-channel thin film magnetic head for an electronic still camera.

FIG. 1 shows a schematic plan view of the head pattern of a 2-channel thin film magnetic head for an electronic still camera immediately before welding the protective plate. The height positioning pad pattern 2 is set to remain in all pattern etching steps. That is, in each etching step, the pattern according to the present invention is masked by a resist pattern, or etching is performed under conditions such that the pattern is not etched.

As a result, in the configuration of a general magnetic head, as shown in FIG. 2, the thickest film is formed on the coil overlapping portion 14 of the upper magnetic pole, but in the embodiment of the present invention, the film is thickest than the coil overlapping portion 14 of the upper magnetic pole. The pattern of the example is also several μm higher. In this embodiment, the thickness of the insulating film removed to flatten the insulating film on the coil is higher than the coil over-over portion 14 of the upper magnetic pole.

Next, this processed head substrate 7 is brought into contact with the head protection plate 8. At this time, the protection plate 8 and the head pattern 3 do not come into direct contact with each other due to the height positioning pad pattern 2, making it easier for the glass to flow. The glass bonding conditions were 620°C, the same as in the past.

As a result, in contrast to the conventional method where the distance between the protective plate and the head pattern varies between individual heads due to the deflection of the protective plate when the glass is bonded as shown in FIG. As shown in FIG. 4, the variation between the magnetic head substrate 7 and the protection plate 8 on the sliding surface 12 is extremely small.

In this embodiment, the height positioning pad 2 is set in the cutting edge area I9 that is lost in the process of cutting into individual heads, but of course this positioning pad 2
may be set anywhere on the head pattern 3 as long as it does not affect the characteristics of the magnetic head.

Further, in this embodiment, the positioning pad pattern is formed using only a conventional thin film forming process, but if permitted, a special step of forming a spacer pattern may be provided. In this case, any material can be selected with respect to wear characteristics, film formation, etching characteristics, etc., as long as it can withstand the heat treatment in the glass welding process and has the mechanical strength to withstand the contact between the substrate and the protective plate. I can do it.

As explained above, by using the present invention, it is possible not only to bond the protective plate of a thin film magnetic head with high accuracy (but also to provide a manufacturing method that is inexpensive and has high throughput). .

[Brief explanation of drawings]

FIG. 1 is a plan view of a thin film magnetic head pattern for explaining the present invention in detail, FIG. 2 is a cross-sectional view of a magnetic head for explaining the manufacturing process of a conventional thin film head, and FIG. FIG. 4 is a cross-sectional view of a magnetic head for explaining the conventional problems, FIG. 4 is a cross-sectional view of the magnetic head for explaining the present invention in detail, and FIG. 5 is a perspective view showing the configuration of a general thin film head. (Partial sectional view), FIGS. 6(a) and 6(b) are sectional views of a magnetic head for explaining the manufacturing process of a conventional thin film head. DESCRIPTION OF SYMBOLS 1... Upper magnetic pole, 2... Height positioning pad, 3... Thin film head pattern, 4... Lower magnetic pole, 5... Insulating layer, 6... Coil conductor, 7... Substrate , 8... Protective plate, 9... Adhesive, 9a... Mechanical adhesive layer during adhesion, 10... Protective film of inorganic material, 11a-11b... Plane to be polished, 12 ...Medium sliding surface, I3...Gap, 14...Cover over part 11B of the upper magnetic pole coil...
·Spacer,

Claims (1)

[Claims] In the manufacturing process of a thin film magnetic head, a height positioning pad is formed so that a thin film pattern laminated thicker than the upper magnetic pole is formed on the substrate at the end of the thin film process; A method for manufacturing a magnetic head comprising the steps of fixing a head protection plate and a magnetic head pattern using the pattern as a reference plane, and welding by pouring molten glass between the magnetic head pattern and the protection plate.