JPH0552564B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a method for manufacturing a thin-film magnetic head, which is constructed by bonding a protective substrate onto a substrate on which a thin-film magnetic head pattern is formed. be.

(b) Prior art In general, in order to mount a thin film magnetic head in which a magnetic layer, a conductive layer, etc. are patterned and formed on a wear-resistant substrate, it is necessary to improve the wear resistance of the tape-contacting surface of the head. In order to improve the performance, it is necessary to adhere a wear-resistant protective substrate onto such a pattern. The adhesive material used for such bonding has a certain degree of abrasion resistance, and the working temperature is about 400℃ so that the magnetic properties of the thin film magnetic head will not deteriorate due to the heating temperature increase during bonding. It is common to use lead-containing glass. Furthermore, when performing such bonding, at least the thickness of the adhesive layer, which generally has lower abrasion resistance than the above-mentioned substrates, should be made as thin as possible, the air bubbles remaining in the adhesive layer should be minimized, and the thin film magnetic material should be used. The protective board must be glued only near the tape-contacting surface of the head, and the terminal section for connecting the external circuit to the head should be left exposed. It is desirable to be able to perform bonding processing on individual head patterns at the same time.

(c) Purpose of the Invention The present invention has been made in view of the above points, and is capable of bonding protective substrates that meet the above-mentioned conditions.

(d) Structure of the Invention That is, according to the present invention, in order to achieve the above-mentioned object, there is provided a thin film magnetic head constructed by bonding a protective substrate onto a substrate formed with a thin film magnetic head pattern. a first groove used for releasing the adhesive during the bonding process on the protective substrate;
A second groove used for cutting during molding after completion of adhesion is formed in advance.

(E) Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a method of manufacturing a magnetoresistive thin film magnetic head for reproduction using a magnetoresistive element as an electromagnetic transducer will be described.

First, Figure 1 shows a cross-sectional view of a magnetoresistive thin film magnetic head after the magnetic layer, conductive layer, insulating layer, etc. have been patterned and formed. 2 is a conductive layer, 3 is an insulating layer, and 4 is a substrate on which each pattern is formed. In the case shown in Fig. 1, a glass adhesive 5 is placed on the portion A covered with the insulator layer 3, and a protective groove is preliminarily cut on top of the glass adhesive 5 as shown in Fig. 2. The third board 6
Arrange as shown. Here, the first groove 6a of the protective substrate 6 is used to release the glass adhesive 5, and specifically, the glass adhesive 5 that has softened upon reaching the working temperature range spreads between the two substrates 4 and 6. The terminal part where the conductor layer 2 is exposed (Fig. 1B)
The second groove 6b is used for cutting during the molding process after the adhesion is completed, and specifically, the second groove 6b is used to prevent the protective substrate 6 from being adhered to the terminal part after the adhesion process is completed. This is for cutting and removing a certain protective substrate without damaging each pattern.

Next, hold the protective substrate 6 in the arrangement shown in FIG. (In order to prevent damage to the glass, apply pressure to the extent that the arrangement state does not shift)) Heat the glass adhesive material 5 to the working temperature range (the range where the glass softens and performs the adhesive function), and the temperature reaches the specified glass bonding temperature. When the working temperature range of material 5 is reached, the pressure is increased.
As a result, the softened glass adhesive 5 is applied to both the substrates 4 and 6.
The glass adhesive 5 spreads into the gap and becomes thinner, and the excess glass adhesive 5 flows into the first groove 6a formed in the protective substrate 6 and is absorbed. Therefore, both boards 4 and 6
The glass adhesive layer between them is very thin, and there is no possibility that glass will adhere to the conductor layer 2 of the terminal section or that the protective substrate 6 will be bonded to the terminal section. After the bonding process is maintained within the working temperature range of the glass bonding material for about 10 minutes, for example, the temperature is lowered to room temperature without reducing the pressure, thereby completing the bonding process, resulting in the state shown in FIG. 4.

Therefore, after the bonding step is completed, a magnetoresistive thin film magnetic head that can be mounted is obtained by cutting at the positions indicated by cutting lines C, D, and E shown in FIG. At this point, only the protective board 6 is cut to expose the terminal section to which the external circuit is connected.
At this position, since the second groove 6b for cutting is formed in the protective substrate 6 in advance, the conductor layer 2
This can be done without damaging each pattern.

Note that the glass adhesive 5 has a working point.
A glass ingot made by melting and mixing the ingredients to a temperature of about 400℃ is 10mm long, 1mm wide,
It is preferable to use etching that has been cut into strips about 0.2 mm thick, surface-etched with an aqueous solution (hydrofluoric acid + ammonium fluoride), and then thoroughly cleaned. (1st
It becomes difficult to place glass as an adhesive only in part A) in the figure, and there are also problems such as air bubbles tending to remain in the adhesive layer after adhesion. Here, the purpose of surface etching is to shape the glass adhesive into a thinner glass adhesive due to the limitations of the rectangular shape that can be easily obtained by cutting the glass ingot, and to smooth out small scratches on the surface caused by cutting. We are conducting this as
This has the effect of reducing the number of air bubbles remaining in the adhesive layer after adhesion.

As described above, by using the manufacturing method according to the present invention, a protective substrate can be simultaneously bonded to a plurality of head patterns formed on a substrate while satisfying the necessary conditions, and then cutting and forming can be performed. Thus, a desired thin film magnetic head can be obtained.

(f) Effects of the Invention As described above, according to the manufacturing method of the present invention, a thin film magnetic head is produced by adhering a protective substrate to a substrate on which a thin film magnetic head pattern is formed. The protective substrate can be bonded using a thin adhesive layer without leaving any air bubbles or leaking into the terminal area, and it is easy to remove only the protective substrate located on the terminal area after adhesion is completed. can be done.

[Brief explanation of drawings]

The figures show an example of manufacturing a thin film magnetic head according to the present invention, in which Fig. 1 is a sectional view of the thin film magnetic head after the patterning process is completed, Fig. 2 is a sectional view of a protective substrate with grooves, FIG. 3 is a sectional view showing the relative arrangement of the protective substrate and the glass adhesive, and FIG. 4 is a sectional view showing the state at the end of the bonding process and the subsequent cutting position. DESCRIPTION OF SYMBOLS 1... Magnetic layer, 2... Conductor layer, 4... Substrate for base, 5... Glass adhesive, 6... Protective substrate, 6a, 6b... First and second grooves.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a thin-film magnetic head, which comprises bonding a flat surface of a protective substrate onto a substrate on which a thin-film magnetic head pattern is formed, wherein the protective substrate is bonded to the flat surface of the protective substrate. A first groove used for releasing the adhesive material and a second groove used for cutting and removing the protective substrate on the terminal portion of the thin film magnetic head pattern after the completion of bonding are formed in advance. Then, the protective substrate was placed on the substrate on which the thin film magnetic head pattern was formed via a glass adhesive, and the temperature was raised while applying pressure until the temperature reached a predetermined working temperature range of the glass adhesive. After that, the pressure is increased to reduce the thickness of the glass adhesive interposed between both substrates, and the remaining glass adhesive is removed from the first substrate.
The protective substrate on the terminal portion can be removed without damaging the thin film magnetic head pattern by absorbing it in the groove and cutting it from the back side of the second groove of the protective substrate after cooling down. A method for manufacturing a characteristic thin film magnetic head. 2. The method of manufacturing a thin film magnetic head according to claim 1, wherein a rectangular thin glass plate whose surface is etched is used as the glass adhesive.