JPS5856162B2 - thin film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin-film magnetic head used in a magnetic storage device, etc., and in particular, a magnetic pole piece made of a magnetic thin film surrounding a multilayer conductor insulated from each other by an insulator made of a non-magnetic thin film. The present invention also relates to a thin film magnetic head in which a writing/reading gap is formed.

FIG. 1 shows a typical structural example of a conventional single-turn coil type thin film magnetic head, in which FIG.

A thin film magnetic head has a magnetic material 2a such as permalloy on a nonmagnetic substrate 1 such as silicon or nonmagnetic ferrite.
, 2b, S io 2 , T
It surrounds a conductor 4 made of Au, Al, Cu, etc. which is electrically insulated by non-magnetic insulators 3a, 3b such as a 20 =, and is composed of a gap g.

In the case of such a thin film magnetic head, the width of the gap g is determined by the thickness of the insulator.

Generally, the thickness of this insulator is about 0.5 μm to 1.0 layers, so the gap width in this case is about 1.0 μ to 2.0 layers.

2. Description of the Related Art In recent years, as storage devices have become more dense and data processing speeds have become faster, thin film magnetic heads have been actively developed to have multi-turn coils.

Figure 2 shows a cross-sectional view of a three-turn coil type thin film magnetic head.
Give an example.

In FIG. 2, the same reference numerals as in FIG. 1 indicate the same or equivalent parts in FIG.

Conductors 4a, 4b, and 4c corresponding to the windings of a conventional head are insulators 3a.

It is surrounded by 3 b t 3 c and 3 d and is electrically insulated.

Further, the gap is formed in the same manner as in a single-turn coil type thin film magnetic head, and the gap width in this case is about 2.0 μm to 4.0 layers since it is made of four layers of insulators.

As described above, since the multi-turn coil type thin film magnetic head has a large number of laminated layers, the gap width tends to become large.

However, as described above, in order to accommodate higher storage density and faster data processing, it is necessary to narrow the gap width.

For this reason, the present inventors devised a multi-turn coil type thin film magnetic head with a narrow gap width as shown in FIG.

In this method, a gap is formed by the lower insulator 3a, and a thin film made of a material having different etching characteristics from the intermediate insulators 3c, 3d and the upper insulator 3b is formed over the lower insulator 3a, and the upper magnetic The middle and upper insulator 3b of the gap portion are removed by etching, leaving only the upper insulator 3a, thereby forming a gap.

However, according to this method, since the middle and upper insulators are etched at the same time, the etching wraps around and a so-called over-etched portion A is created at the end of the conductor.

As a result, an electrical short circuit occurs between each base and the upper magnetic body,
This will significantly impair the performance of the thin film magnetic head.

Therefore, there is a drawback that it causes a decrease in product yield.

An object of the present invention is to provide a multi-turn coil type multilayer thin film magnetic head that is free from electrical short circuits between conductors as described above and has a narrow gap width.

In the present invention, a magnetic pole piece made of a magnetic thin film surrounds a multilayer conductor layer which is insulated from each other by an insulator made of a non-magnetic thin film, and a gap is formed by the top layer of the non-magnetic thin film constituting the insulator. This achieves the above objectives.

An embodiment of the present invention will be explained with reference to FIG.

In FIG. 4, the same reference numerals as in FIG. 3 indicate the same or corresponding parts as in FIG. 3, and a, b, c in FIG.
The figure shows the example in the order of manufacturing steps.

In this embodiment, first, before forming the upper insulator 3b, a photoresist 5 is formed as shown in FIG. Figure b.

Next, the upper insulator 3b is shaped, the upper insulator of the back gap part B is removed in a photo-etching process, and the upper magnetic body 2b is formed on top of it, and the gap G is further cut and polished. FIG.

As a result of the above structure, it is possible to form a thin insulating film at the ends of the conductors, and as a result, electrical short circuits between the conductors due to the upper magnetic material can be prevented, and the thickness of the upper insulator can be reduced. The gap width can be arbitrarily selected by adjusting .

As explained above, according to the present invention, in a thin film magnetic head having a multilayer structure of conductors, electrical short circuits between conductors can be eliminated and the gap width can be narrowed, resulting in a large output voltage and high reliability. A thin film magnetic head suitable for high density recording can be obtained.

[Brief explanation of the drawing]

1, 2, and 3 are perspective views and sectional views for explaining a thin film magnetic head, and FIG. 4 is a sectional view showing an embodiment of the thin film magnetic head according to the present invention in the order of manufacturing steps. 1: Substrate, 2a: Lower magnetic body, 2b Upper magnetic body, 3a
: Lower insulator, 3b, upper insulator, 4: conductor, 3c,
3d: Intermediate insulator, A nitrogen-etched part, B
: back gap part, 5: photoresist, g, G: gap.

Claims (1)

[Claims] 1. In a thin-film magnetic head constructed by surrounding a multilayer conductor insulated from each other by an insulator made of a non-magnetic thin film with a magnetic piece made of a magnetic thin film, writing and reading can be performed using only the top layer of the non-magnetic thin film constituting the insulator. A thin film magnetic head characterized by having a gap formed therein.