JPH0196814A - Composite type thin film magnetic head - Google Patents

Abstract

PURPOSE:To flatten the upper part of a recording head and to accurately form a magnetic resistance element which becomes a reproducing head by forming a recessed part at the substrate of a composite type thin film magnetic head beforehand and forming a recording head on the substrate having the recessed part. CONSTITUTION:At a substrate 1 of a composite type thin film magnetic head, a groove is formed in which the taper angle of a side surface is about 20-45 deg. and a depth is about 8mum by dry etching, and continuously, a lower part electrode 2 formed by a ferromagnetic alloy is adhered. Next, an insulating layer 4 and a coil 3 due to a high polymer resin are successively laminated and to the formed recessed groove part, a coil 3 and an insulating layer 4 are filled. Further, after the upper part is flattened by the applying and etching-back of the high polymer resin, an insulating layer 4' to form the gap part is obtained, one of them is removed and an upper part magnetic pole 5 is formed. Thereafter, an insulating layer 8 is adhered, a magnetic resistance effect type reproducing head 6 is laminated on it, the upper part of the recording head is flattened and a reproducing head is formed accurately on it.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to magnetic recording for magnetic disks, VTRs, etc.
In particular, the present invention relates to a thin film magnetic head suitable for high-density magnetic recording.

[Conventional technology]

Techniques for combining an inductive thin film magnetic head and a magnetoresistive magnetic head include (1) forming an inductive thin film magnetic head on a magnetoresistive head; (2) A magnetoresistive head is formed between the magnetic poles of the inductive magnetic head. (3) Three structures have been proposed in which a magnetoresistive head is formed on an inductive thin film magnetic head. These techniques are described in Japanese Patent Application Laid-Open No. 51-148
No. 411, JP-A-52-11921, JP-A-58-1
No. 89818.

Among these technologies, a composite head with a structure in which a magnetoresistive magnetic head is stacked on top of a third inductive magnetic head, as shown in Fig. Since the head is placed in a structure, reading can be performed immediately after writing.

Therefore, the written information can be confirmed, and the error rate in magnetic recording can be extremely reduced.

[Problem that the invention seeks to solve]

However, in the above-mentioned prior art, as shown in FIG. 2, since the recording head is formed on a flat substrate, a stepped portion 7 of the recording head is generated in the vicinity of the portion where the reproducing head is formed.

In this way, it has been difficult to form a reproducing head with high precision because a sufficiently flat portion cannot be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a composite thin-film magnetic head in which the upper part of the recording head can be flattened to form a reproducing head with high precision.

[Means for deciding issues]

The above object is achieved by forming a recording head on a substrate that has recesses in advance.

[Effect]

The operation of the present invention will be explained using FIG. The substrate 1 is processed in advance to form a recessed portion having gentle side surfaces. Subsequently, the lower magnetic pole 2 is formed, and the excitation coil 3 is formed in the recess. Thereafter, an insulating layer 4 is laminated on the coil 3 and planarized, and then the magnetic pole 5 is formed. At this time, since the coil 3 can be formed in the recessed part of the substrate, no step is formed in the gap part of the recording head, and a flat surface can be obtained. Therefore, the magnetoresistive type reproducing head 6 can be formed thereon with high accuracy.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. First, a groove with a depth of about 8 μm is formed in the substrate 1. At this time, taper etching is performed using dry etching so that the taper angle of the side surface is 20' to 45'' (see Figure 3).
a)). Subsequently, a ferromagnetic alloy forming the lower magnetic pole 2, such as N1-Fe, Fe-AQ, Go
Approximately 3 μm of amorphous alloy or the like is deposited and processed (Fig. 3(b)). Next, S i 02. A n zos,
An insulating layer 4 made of Si 8N4 or polyimide polymer resin, and a coil 3 made of AQ, Cu, or the like are sequentially laminated, and the coil 3 and insulating layer 4 are filled in the recess. (3rd
Figure (C)).

At this time, the coil 3 had a film thickness of 3 μm and was formed using lift-off. Furthermore, planarization was performed using a polymer resin coating and an etch-back method. Next, as the insulating layer 4' forming the gap part, A I2.208 was coated with a thickness of 0.5 μm.
After being deposited, a part of it is removed, and then the magnetic pole 5 is formed (FIG. 3(d)).

The material and film thickness are the same as those for the lower magnetic pole.

After that, as the insulating layer 8, AQ 203 was coated with a thickness of about 0.5 μm.
Then, a magnetoresistive reproducing head 6 is deposited thereon.
were laminated. As a reproducing head, a shunt bias type magnetoresistive element made of a Ni--Fe alloy (400 thick) and a Ti film (2000 thick) was used. Note that as the reproducing head, a magnetoresistive element using other bias methods such as a barber pole type or a permanent magnet type can also be used. Furthermore, although a magnetoresistive head is used as the reproducing head in this embodiment, an inductive thin film head may also be used. If a shield film is required in the 6B pneumatic read head, it is also possible to laminate a soft magnetic film such as permalloy on the top of the read head.

As described above, since the upper part of the recording head can be made flat, a magnetoresistive type reproducing head can be formed thereon with high accuracy.

Example 2 This example will be explained using FIG. 4. The substrate 1 is processed using the taper etching method as in Example 1 (FIG. 4(a)). Subsequently, the lower magnetic pole 2 is formed, and then the insulating layer 4 and the conductive coil 3 are sequentially laminated to fill the concave portion of the substrate with the coil.

The surface is flattened ((b) in the same figure). At this time, each material and film thickness are the same as in Example 1. Next, an AQzOa film (approximately 0.5 .mu.m) is laminated as an insulating layer 4' serving as a gap layer, and then the resin layer is taper-etched in order to make contact with the lower magnetic pole (FIG. 4(C)). Furthermore, the upper magnetic pole 5 and the insulation M8 are laminated, and then Example 1
Similarly, a magnetoresistive type reproducing head 6 is formed thereon.

In this embodiment, unlike the previous embodiment, it is necessary to form a contact hole 9 for making contact between the upper magnetic pole and the lower magnetic pole. However, when filling the four parts with the insulating layer and the coil, since there is no convex part of the substrate at the center of the coil, there is an advantage that one surface can be flattened more easily than in the case of the first embodiment. As described above, according to this embodiment, since the upper part of the recording head can be made flat, the reproducing head can be formed thereon with high precision.

〔Example〕

This embodiment will be explained using FIG. 5. In the embodiment, a ferromagnetic substrate such as Ni-Zn or Mn-Zn ferrite is used as the substrate 1'. For this purpose, a concave portion with a gentle cross section is formed in the substrate by 6-taper etching, in which the substrate becomes the lower magnetic pole (FIG. 4(a)). Next, Example 1
Similarly to the process shown in 1, the recessed portion of the substrate is filled with the magnet 11M4 and the coil 3, and then the upper magnetic pole 5 and the magnetoresistive read head 6 are laminated.

In the example, since the substrate is used as the lower magnetic pole, it is not necessary to form the lower magnetic pole, and the manufacturing process can be simplified.

〔Effect of the invention〕

According to the present invention, it is possible to flatten the upper magnetic pole surface of the recording head by forming a coil in the groove on the substrate side.
There is an advantage that a magnetoresistive element that becomes a reproducing head can be formed with high precision thereon.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a composite magnetic head of the present invention, FIG. 2 is a sectional view of a conventional composite magnetic head, and FIGS. 3 to 5 are sectional views showing the head manufacturing process of an embodiment of the modified invention. 6 1... Substrate, 2... Lower magnetic pole, 3... Coil, 4
...Insulation No. 1 Fig. 2 Fig. 74 Difference 3 Fig. 4 Insulation 1 and glaze j Fig. 4 Fig. 5 Fig. 6 Towards rebirth, Sho'

Claims (1)

[Claims] 1. In a thin-film head that includes an inductive magnetic head and a magnetoresistive magnetic field detection section thereon via an electrically insulating layer, a portion of the lower magnetic layer, conductor layer, and insulating layer of the inductive magnetic head is 1. A composite thin-film magnetic head, which is embedded in a groove of a substrate which has been grooved in advance, and wherein the surface of the magnetic layer is substantially parallel to a horizontal plane of the substrate.