JPH03214410A - Thin-film magnetic head - Google Patents

Abstract

PURPOSE:To improve the efficiency of a magnetic flux with respect to a recording current by constituting an upper magnetic layer of a horizontal part parallel with a coil layer and sloped part provided at both ends of the horizontal part. CONSTITUTION:The upper magnetic layer 10 is formed of the horizontal part 11 parallel with the coil layer 6 and the sloped parts 12 formed integrally at both ends of the horizontal part 11. The magnetic flux is thereby jumped to the outside from the straight sloped parts 12 and the magnetic flux which passes the gap layer 4 without jumping to the outside and flowing to the lower mag netic layer 3 is fairly decreased. The quantity of the magnetic flux pumping to the outside with respect to the magnitude of the recording current is thus increased and the efficiency is improved. Namely, the large magnetic flux is generated even with the small current and heat is not much generated in the coil layer 6, by which the generation of the insulation defect of the interlayer insulating layer by the heat is prevented. The direct flow of the magnetic flux to the other magnetic layer beyond the magnetic gap is suppressed and, there fore, the efficiency of the magnetic flux with respect to the recording density is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thin film magnetic head used in a magnetic recording/reproducing device.

Prior Art FIG. 5 is a sectional view showing a conventional thin film magnetic head. In Fig. 5, 1 is a substrate made of a non-magnetic material such as ceramic, 2 is an insulating film formed by sputtering a material such as silicon dioxide on the substrate, and 3 is an insulating film formed on the insulating film 2 by sendust or the like. The formed lower magnetic layer 4 is a gap layer formed on the lower magnetic layer 3 and serves as a magnetic gap, 5 is an interlayer insulating layer formed of photoresist or the like on the gap layer, and 6 is an insulating layer 5 between the eyebrows. The coil layer 6 is formed by first forming a conductive thin film of copper or the like, and then finishing it into a predetermined shape using a technique such as photolithography. 7 is an interlayer insulating layer formed on the coil layer, 8 is an upper magnetic layer formed on the glabella insulating layer 7, and the upper magnetic layer 8 has a sloped portion 8a.
and an outer throat portion 8b parallel to the lower magnetic layer 3. Further, the end surface of the outer throat portion 8b constitutes a medium facing surface. 9 is a protective layer formed on the upper magnetic layer.

In the thin film magnetic head constructed as described above, when a current is passed through the coil layer 6, a magnetic flux flows in the direction of arrow A shown in FIG. 5, and magnetic recording is performed on the magnetic recording medium. Further, during reproduction, magnetic flux from the magnetic recording medium flows into the upper magnetic layer 8 and the lower magnetic layer 3, and an induced electromotive force is generated in the coil layer 6. Then, a current flows in the coil layer 6, and the resulting voltage is extracted as a signal.

Problems to be Solved by the Invention However, in the conventional configuration, when magnetic flux flows from the sloped part 8a of the upper magnetic layer 8 to the outer throat part 8b shown in FIG. 6 during recording, the magnetic flux flows from the sloped part 10 to the outer throat part 8b. The amount of magnetic flux that does not go to the throat portion 8b but passes through the gap layer 4 and enters the lower magnetic layer 3 and jumps out to the medium opposite to the recording current is reduced, and more recording current is required to obtain a predetermined magnetic flux strength. The problem was that it had to be washed away. The reason why the magnetic flux passes through the gap layer 4 and flows into the lower magnetic layer 3 is that the magnetic resistance is higher when the magnetic flux passes through the gap layer 4 and enters the lower magnetic layer 3 than when it bends from the slope part 8a to the outer throat part 8b. This is because it becomes smaller. A similar decrease also occurs when the direction of magnetic flux flow is from the lower magnetic layer to the upper magnetic layer.

The present invention solves the above-mentioned conventional problems, and provides a thin film magnetic head that can reduce the amount of magnetic flux that flows into the other magnetic layer by passing through the gap layer without jumping out from the medium facing surface. 1] Targeted.

Means for Solving the Problem In order to achieve this object, the upper magnetic layer is composed of a horizontal part parallel to the coil layer and an inclined part provided at both ends of the horizontal part, and the ends of the inclined part are arranged so as to face the medium. It was a face.

Function: With this configuration, it is possible to prevent magnetic flux from flowing directly into other magnetic layers by passing through the magnetic gap.

Embodiment FIG. 1 is a sectional view showing a thin film magnetic head in an embodiment of the present invention. In FIG. 1, l is a substrate, 2 is an insulating film, 3 is a lower magnetic layer, 4 is a gap layer, 5 is an interlayer insulating layer, 6 is a coil layer, 7 is an interlayer insulating layer, 9 is a protective layer, and these are conventional The configuration is the same as that of Reference numeral 10 denotes an upper magnetic layer, and the upper magnetic layer 10 is composed of a horizontal portion 11 parallel to the coil layer 6 and an inclined portion 12 integrally formed at both ends of the horizontal portion 11. At this time, the end face of the inclined portion 1 of the medium facing surface constitutes a part of the medium facing surface.

Regarding the thin film magnetic head configured as described above, the flow of magnetic flux during recording will be explained below.

FIG. 2 is an enlarged cross-sectional view showing the flow of magnetic flux during recording in a thin film magnetic head according to an embodiment of the present invention. As shown in FIG. 2, the magnetic flux directly jumps out from the inclined portion l2. Therefore, the magnetic flux that passes through the gap debris 4 and flows into the lower magnetic layer 3 without flying out is considerably reduced, and the amount of magnetic flux flowing out relative to the magnitude of the recording current becomes large, resulting in improved efficiency. In other words, a large magnetic flux can be generated even with a small recording current, so that little heat is generated in the coil layer 6, and insulation defects in the interlayer insulating layer due to heat can be prevented.

A method of manufacturing the thin film magnetic head constructed as described above will be described below.

First, an insulating film 2 is formed on a substrate l, and a lower magnetic layer 3 is formed on the insulating film 2. Next, a gap layer 4 is formed on the lower magnetic layer 3 using silicon dioxide or the like. Next, an interlayer insulating layer 5 is formed on the gap layer 4 by using a photoresist or the like.
form. Next, a conductive thin film is formed of steel or the like on the interlayer insulating layer 5, and the conductive thin film is processed into a spiral shape using photolithography to form the coil layer 6. Next, an interlayer insulating layer 7 is formed using photoresist or the like so as to cover the coil M6. Next, an upper magnetic layer 10 is formed on the interlayer insulating layer 7 so as to constitute a magnetic circuit together with the lower magnetic layer, and a protective layer 9 is formed thereon. Next, the individual substrate 1 serving as the medium facing surface and the laminated thin film body are polished. At this time, polishing is performed so as not to reach the abex 10 shown in FIG. 1, and until the inclined portion l2 is exposed on the polishing surface.

As described above, according to this embodiment, the inclined portion 1 of the upper magnetic layer 10
By making the end face of 2 constitute a part of the medium facing surface, the magnetic flux is allowed to directly jump out from the inclined portion 12.

Therefore, the magnetic flux that passes through the gap layer 4 and flows into the lower magnetic layer 3 without jumping out is considerably reduced, and the amount of magnetic flux flowing outside increases relative to the magnitude of the recording current, improving efficiency.

In this embodiment, the upper magnetic layer 10 has a horizontal portion 11 and a sloped portion 12, but a thin film magnetic head in which the lower magnetic layer has a horizontal portion and a slope parallel to the coil layer as shown in FIG. I was able to get some results. In FIG. 3, 13 is a substrate, and a recess 13a is provided in the substrate l3. l4 is an insulating layer formed all over the surface on which at least the four parts 13a are formed, l5 is a lower magnetic layer formed on the insulating layer 14, and the lower magnetic layer l5 covers the horizontal part 15a and both ends of the horizontal part 15a. It is composed of an inclined portion 15b provided at a portion. 16 is a gap layer formed on the lower magnetic layer, 17 is an interlayer insulating layer formed on the gap layer 16, 18 is a coil layer formed on the interlayer insulating layer l7,
19 is an interlayer insulating layer formed on the coil layer 18; 20
is an upper magnetic layer formed on the interlayer insulating layer 19, and 21 is a protective layer formed on the upper magnetic layer 20. In the thin film magnetic head constructed in this manner, the magnetic flux can also be reduced by passing through the gap layer 16 and toward the other magnetic layer without jumping out to the medium facing surface.

Further, as shown in FIG. 4, a similar effect can be obtained by providing both the upper magnetic layer and the lower magnetic layer with horizontal portions and inclined portions parallel to the coil layer. In FIG. 4, 13 is a substrate, 13a
14 is an insulating layer, 15 is a lower magnetic layer, 15a is a horizontal portion, 15b is an inclined portion, 16 is a gap layer, 17 is an insulating layer between the eyebrows, 18 is a coil layer, 19 is an insulating layer between the eyebrows, and these are the third The configuration is the same as that shown in the figure. 22 is an interlayer insulating layer 19
The upper magnetic layer 22 includes a horizontal portion 22a parallel to the coil layer 18 and inclined portions 22b provided at both ends of the horizontal portion 22a.

Reference numeral 20 denotes a protective layer formed on the upper magnetic layer 22, which has the same structure as that shown in FIG. Even in a thin film magnetic head having such a structure, it is possible to reduce the magnetic flux that passes through the gap layer l6 and goes toward the other magnetic layer without jumping out to the medium facing surface.

Effects of the Invention In the present invention, the upper magnetic layer is composed of a horizontal part parallel to the coil layer and an inclined part provided at both ends of the horizontal part, and the end of the inclined part is made into a surface facing the medium, so that the magnetic flux is distributed over the magnetic gap. Since it is possible to prevent the magnetic flux from flowing directly into other magnetic layers by passing through the magnetic layer, it is possible to improve the efficiency of the magnetic flux with respect to the recording current.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a side sectional view showing a thin film magnetic head in one embodiment of the present invention, FIG. 2 is an enlarged sectional view of the same portion, and FIG. 3 is a sectional view showing another embodiment. FIG. 4 is a sectional view showing another embodiment, FIG. 5 is a side sectional view showing a conventional thin film shaft head, and FIG. 6 is an enlarged sectional view of the same portion. 1 1 1 1... Substrate 2... Insulating film 3... Lower magnetic layer 4... Gap layer 5... Interlayer insulating layer 6 ......Coil layer 7...Interlayer insulating layer 9...Protective layer 0...Top magnetic layer, l...Horizontal portion 2...・・・・Slope part

Claims (1)

[Claims] a substrate, a lower magnetic layer formed on the substrate, a gap layer formed on the lower magnetic layer, a coil layer formed on the gap layer and covered with an interlayer insulating layer, The upper magnetic layer includes an upper magnetic layer formed on the coil layer, and the upper magnetic layer is composed of a horizontal part parallel to the coil layer and an inclined part provided at both ends of the horizontal part, and the inclined part includes: A thin film magnetic head characterized in that an end of the inclined portion on the side of the medium facing surface forms a medium facing surface.