JP2563625B2 - Thin film magnetic head - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thin film magnetic head used in a magnetic recording / reproducing apparatus.

2. Description of the Related 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 ceramics, 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 formed on the lower magnetic layer 3, and serves as a magnetic gap. The gap layer 5 is an interlayer insulating layer formed of photoresist or the like on the gap layer. 6 is the interlayer insulating layer 5.
The coil layer 6 is formed by forming a conductive thin film of copper or the like first, and then finishing it into a predetermined shape by using a technique such as photolithography. Reference numeral 7 is an interlayer insulating layer formed on the coil layer, 8 is an upper magnetic layer formed on the interlayer insulating layer 7, and the upper magnetic layer 8 has an inclined portion 8a.
And an outer throat portion 8b parallel to the lower magnetic layer 3. The end surface of the outer throat portion 8b constitutes a medium facing surface. Reference numeral 9 is a protective layer formed on the upper magnetic layer.

The thin film magnetic head configured as described above has 6 coil layers.
When a current is applied to the magnetic flux, a magnetic flux flows as shown by arrow A in FIG.
Magnetic recording is performed on a magnetic recording medium. During reproduction, the magnetic flux from the magnetic recording medium flows into the upper magnetic layer 8 and the lower magnetic layer 3 to generate an induced electromotive force in the coil layer 6. Then, a current flows through the coil layer 6, and the voltage is taken out as a signal.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described conventional configuration, when the magnetic flux flows from the inclined portion 8a of the upper magnetic layer 8 shown in FIG. 6 to the outer throat portion 8b during recording, the magnetic flux flows from the inclined portion to the outer portion. The amount of magnetic flux that does not go to the throat portion 8b, passes through the gap layer 4 and enters the lower magnetic layer 3 and jumps out to the medium facing surface with respect to the recording current, so that more recording current is obtained in order to obtain a magnetic flux of a predetermined strength. It had a problem that it had to be flushed. 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 greater when the magnetic flux passes through the gap layer 4 and enters the lower magnetic layer 3 than when the magnetic flux bends from the inclined portion 8a to the outer throat portion 8b. Because it becomes smaller. A similar decrease occurs in the direction in which the magnetic flux flows 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 capable of reducing the amount of magnetic flux passing through a gap layer and flowing into the other magnetic layer without protruding from the medium facing surface. Has an aim.

In order to achieve this object, at least one of the first and second magnetic layers has a horizontal portion facing the coil layer, and a horizontal portion provided at an end of the horizontal portion. Has an inclined portion that is inclined with respect to, and at the end of the inclined portion,
The facing portion that constitutes the medium facing surface and the gap contact portion that is adjacent to the facing portion and that contacts the gap layer are provided.

Action With this configuration, it is possible to prevent the magnetic flux from passing through the magnetic gap and directly flowing into another magnetic layer, and further, it is possible to prevent the apex that determines the gap depth from being exposed to the outside.

EXAMPLE FIG. 1 and FIG. 2 are a sectional view and a partially enlarged sectional view, respectively, showing a thin film magnetic head in one embodiment of the present invention. In FIGS. 1 and 2, 1 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, and 9 is a protective layer. , These are the same as the conventional configuration. Reference numeral 10 is an upper magnetic layer, and the upper magnetic layer 10 is a horizontal portion facing the coil layer 6 and parallel to it.
11 and an inclined portion 12 formed integrally with both ends of the horizontal portion 11. Further, at the end of the inclined portion 12, a facing portion 12c forming a part of the medium facing surface 100 and a gap contacting portion 12b provided adjacent to the facing portion 12c and contacting the gap layer 4 are integrally formed. Has been formed. 12a is the gap depth
Determine GD (length of the gap contact part 12b) and set the upper magnetic layer 1
Apex formed at 0. With such a configuration, the apex 12a is not exposed to the medium facing surface 100,
The gap depth GD does not change due to the lack of the apex 12a, and the magnetic characteristics and the like of the thin film magnetic head do not deteriorate.

With respect to the thin-film magnetic head configured as described above, the flow of magnetic flux during recording will be described below. As shown in FIG. 2, the magnetic flux comes out directly from the inclined portion 12. Therefore, the magnetic flux flowing through the gap layer 4 without flowing out to the lower magnetic layer 3 is considerably reduced, and the amount of magnetic flux jumping to the outside with respect to the magnitude of the recording current is increased and the efficiency is improved. That is, a large magnetic flux can be generated even with a small recording current, heat is not generated much in the coil layer 6, and it is possible to prevent the occurrence of insulation failure of the interlayer insulating layer due to heat.

A method of manufacturing the thin film magnetic head having the above structure will be described below.

First, the insulating film 2 is formed on the substrate 1, and the lower magnetic layer 3 is formed on the insulating film 2. Next, the gap layer 4 is formed on the lower magnetic layer 3 with silicon dioxide or the like. Next, the interlayer insulating layer 5 is formed on the gap layer 4 with photoresist or the like. Next, a conductive thin film is formed of copper or the like on the interlayer insulating layer 5, and the conductive thin film is processed into a spiral shape by using a photolithography technique to form the coil layer 6. Next, the interlayer insulating layer 7 is formed of photoresist or the like so as to cover the coil layer 6. Next, an upper magnetic layer 10 is formed on the interlayer insulating layer 7 so as to form a magnetic circuit with the lower magnetic layer, and a protective layer 9 is formed thereon. Next, the substrate 1 on the side facing the medium and the laminated thin film body are polished. This time,
2 so that the apex 12a shown in FIG. 2 is not reached, that is, the gap contact portion 12b remains, and the inclined portion 12
Until it is exposed on the polishing surface.

As described above, according to this embodiment, the inclined portion 12 of the upper magnetic layer 10 is
Since the end surface of the magnetic recording medium constitutes a part of the medium facing surface, the magnetic flux directly jumps out from the inclined portion 12. Therefore, the magnetic flux flowing through the gap layer 4 without flowing out to the lower magnetic layer 3 is considerably reduced, and the amount of magnetic flux jumping to the outside with respect to the magnitude of the recording current is increased and the efficiency is improved.

Although the horizontal portion 11 and the inclined portion 12 are formed in the upper magnetic layer 10 in the present embodiment, the same applies to a thin film magnetic head having a horizontal portion and an inclined portion parallel to the coil layer in the lower magnetic layer as shown in FIG. I was able to obtain the effect of. 13 in FIG.
Is a substrate, and the substrate 13 is provided with a recess 13a. Reference numeral 14 denotes an insulating layer formed on at least one surface on which the concave portion 13a is formed, 15 is a lower magnetic layer formed on the insulating layer 14, and the lower magnetic layer 15 is a horizontal portion 15a and both ends of the horizontal portion 15a. It is composed of an inclined portion 15b provided in the section. 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 17, and 19 is a coil layer 18. An interlayer insulating layer formed above, 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.
Also in the thin-film magnetic head having such a structure, it is possible to reduce the magnetic flux passing through the gap layer 16 to the other magnetic layer without jumping to the medium facing surface.

Further, as shown in FIG. 4, the same effect can be obtained by providing a horizontal portion and an inclined portion parallel to the coil layer on both the upper magnetic layer and the lower magnetic layer. In FIG. 4, 13 is a substrate, 13a is a concave portion, 14 is an insulating layer, 15 is a lower magnetic layer, 15a is a horizontal portion, and 15b is a horizontal portion.
Is an inclined portion, 16 is a gap layer, 17 is an interlayer insulating layer, 18 is a coil layer, and 19 is an interlayer insulating layer, which have the same structure as shown in FIG. Reference numeral 22 denotes an upper magnetic layer formed on the interlayer insulating layer 19, and the upper magnetic layer 22 has a horizontal portion 22a parallel to the coil layer 18.
And the 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 the thin film magnetic head having such a structure, it is possible to reduce the magnetic flux that passes through the gap layer 16 to the other magnetic layer without jumping to the medium facing surface.

According to the present invention, at least one of the first and second magnetic layers has a horizontal portion facing the coil layer, and an inclined portion provided at an end of the horizontal portion and inclined with respect to the horizontal portion. Further, at the end of the inclined portion, by providing a facing portion that constitutes the medium facing surface and a gap control portion that is adjacent to the facing portion and is in contact with the gap layer, the magnetic flux Since it is possible to prevent the magnetic flux from passing through the gap and directly flowing into the other magnetic layer, it is possible to improve the efficiency of the speed per hour with respect to the recording current. Also, since the apex that determines the gap depth is not exposed to the outside, even if the magnetic disk and the thin film magnetic head collide, the apex will not be chipped, so the magnetic properties of the thin film magnetic head will deteriorate due to the lack of the apex. It never happens.

[Brief description of drawings]

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, FIG. 3 is a sectional view showing another embodiment, and FIG. 4 is another embodiment. FIG. 5 is a side sectional view showing a conventional thin film magnetic head, and FIG. 6 is a partially enlarged sectional view showing the same. 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 10 ... Upper magnetic layer, 11 ...... Horizontal part 12 …… Sloping part 12a …… Apex 12b …… Gap contact part 12c …… Counter part

Claims (1)

(57) [Claims] 1. A first magnetic layer, a gap layer provided on the first magnetic layer, and a gap layer provided via the gap layer, the magnetic layer forming a magnetic circuit together with the first magnetic layer. A second magnetic layer and a coil layer provided between the first magnetic layer and the second magnetic layer, wherein at least one of the first and second magnetic layers is the coil layer. A horizontal portion facing the layer, and an inclined portion provided at an end portion of the horizontal portion and inclined with respect to the horizontal portion. Further, the end portion of the inclined portion on the medium facing surface side faces the medium. A thin-film magnetic head comprising: a facing portion that forms a surface; and a gap contact portion that is adjacent to the facing portion and that contacts the gap layer.