JPS61131215A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To improve the recoding and reproduction efficiency by constituting a lower magnetic pole of a flat part wherein a recessed part is formed at the part where coils are overlapped on one another, and providing a lower insulating layer in the recess so that the upper surface may lie in the same horizontal surface as the flat part. CONSTITUTION:A lower magnetic pole 3, a lower insulating layer 4, a gap layer 5, coil 6, an upper insulating layer 7, and an upper magnetic pole 8 are successively superposed in order on an insulating layer 2 of a substrate 1, and the coil 6 which is put between the lower insulating layer 4 and the upper insulating layer 7 is arranged between the upper and the lower magnetic pole 8 and 3. Meanwhile, the lower magnetic pole 3 is constituted of a flat part 10 wherein a recess 9 is formed at the part where the coils 6 are overlapped on one another, and the lower insulating layer 4 is arranged in the access 9 of the lower magnetic pole 3 so that the upper surface may lie in the same horizontal surface as the flat part 10.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a thin film magnetic head, and particularly to improvements around a magnetic film layer forming a lower magnetic pole.

(Technical background of the invention and its problems) In a thin film magnetic head, as shown in FIG. 5, a lower magnetic pole is provided on a substrate a, a gap layer C1 and a lower insulating layer d.

The coil e, the upper insulating layer f, and the upper magnetic pole q are stacked in this order, so that the coil e sandwiched between the lower insulating lid and the upper insulating layer f becomes the lower magnetic pole and the upper magnetic pole q. It is placed between. Note that FIG. 6 shows a plane of the thin film magnetic head.

However, with the structure of such a thin film magnetic head, there are problems in that it is difficult to improve the recording and reproducing efficiency, and the precision in forming the coil e by photolithography is low.

In other words, in order to improve the recording and reproducing efficiency, as shown in Figure 7, the distance ρ between the upper and lower magnetic poles 1g that sandwich the coil e is increased to reduce the leakage magnetic flux from between the upper and lower magnetic poles 1g. However, in the structure of the magnetic head described above, the upper and lower magnetic poles are the same.

If the distance q is increased, the stepped portion of the upper 1 ifl pole Q becomes longer, the magnetic resistance increases, and the head efficiency is unintentionally lowered.

On the other hand, the latter coil e is formed by bringing a mask k into close contact with a resist j and exposing the resist j to light through a coil pattern m formed on the mask k, as shown in FIG. , because there is a difference in level from other parts by the thickness of 1aig, although proper exposure can be performed in the part where the mask and resist J are in close contact, there is a gap between mask 1 (and resist J). It has been pointed out that at the step p where the mask k occurs, the light passing through the mask k is diffracted and goes around, inevitably exposing unnecessary parts, which reduces the accuracy of photolithography.
This is an obstacle to forming a coil e with a fine pattern.

[Purpose of the invention]

This invention was made in view of the above circumstances, and its purpose is to improve recording and reproducing efficiency without increasing magnetic resistance, and to easily realize the formation of fine coils. The object of the present invention is to provide a thin-film magnetic head that can be used.

[Main part of the invention, that is, in this invention, the lower magnetic pole is composed of a flat part formed by forming a recess in the part where the coils overlap, and a lower insulating layer is placed in the recess so that the upper surface is in the same horizontal plane as the flat part. By arranging the magnetic poles, it is possible to increase the distance between the upper and lower magnetic poles without increasing the length of the step part, and it is also possible to form a coil on a flat surface without steps. It is something.

[Embodiments of the invention]

The present invention will be described below based on a first embodiment not shown in FIGS. 1 to 3. FIG. 1 shows a thin film magnetic head, where 1 is a substrate, 2 is an insulating layer provided on the substrate 1, 3 is a lower magnetic pole, 4 is a lower insulating layer, 5 is a gap layer, 6 is a coil,
7 is an upper insulating layer, and 8 is an upper magnetic pole. Then, on the insulating layer 2 of the substrate 1, a lower magnetic pole 3. Lower insulating layer 4. Gap layer5. Coil 6° upper insulation layer 7. Upper magnetic poles 8 are stacked in order, and a coil 6 sandwiched between a lower insulating layer 4 and an upper insulating layer 7 is disposed between the upper and lower magnetic poles 3 and 8.

Further, the lower magnetic pole 3, which is the main part of the present invention, is composed of a flat part 10 with four parts 9 formed at the parts where the coils 6 overlap. The lower insulating layer 4 is arranged so as to be in the same horizontal plane as the lower insulating layer 4. Specifically, the recess 9 is formed and the lower insulating layer 4 is disposed using the head manufacturing method shown in FIGS. 2(a) to 2(f).

That is, to explain the method for manufacturing a thin film magnetic head, first, AJ220a and 5io2 are placed on the substrate 1.
The insulating layer 2 is formed on the substrate 1 by forming an insulating layer 2 by sputtering or vapor deposition, or by forming a resist film or an organic polymer film by a spin code.

Next, as shown in FIG. 2(a), the lower magnetic pole 3 and the coil 6 are connected.
A hole 12 is formed by photo-etching at a portion where the two interlock with each other. Next, sputtering and vapor deposition.

Alternatively, in addition to forming a magnetic film on the insulating layer 2 by means such as plating, the magnetic film is formed into a predetermined shape by etching to form the lower magnetic pole 3 as shown in FIG. 2(b). As a result, the lower magnetic pole 3 is connected to the insulating layer 2 as shown in FIG.
It has a concave shape along , and only the part overlapping with the coil 6 is made into a concave part 9, and the other part is made into a flat part 10, thus forming one magnetic ri3. Then, on the insulating layer 2 of the substrate 1 on which the lower magnetic pole 3 is formed, an insulating film is formed on all 5 parts in one piece so as to fill the previous recessed part 9, and then, except for the four parts 9, all other parts are insulated. The film is removed by etching. As a result, the lower insulating layer 4 is formed within the recess 9 as shown in FIG. 2(C). At this time, the upper surface of the lower insulating layer 4 becomes the same horizontal plane as the flat part 10 of the lower magnetic pole 3 without any unevenness, as shown in FIG.

After that, an insulating film is formed on the entire substrate 1 on which the lower magnetic pole 3 is formed, and the lower magnetic pole 3 of the insulating film is
By removing the portion corresponding to the back core portion 3a by etching, a gap layer 5 as shown in FIG. 2(d) is formed.

Then, as in the conventional method, a coil 6 is formed by photolithography on the top surface having no irregularities as shown in FIG. 2(et). After the coil is formed, an upper insulating layer 7 is formed as shown in FIG. The entire thin film magnetic head is formed by forming the upper magnetic pole 8 and further forming the lead extraction.

Thus, in the thin film magnetic head constructed in this way, the length of the stepped portions 8a, 8a of the upper magnetic pole 8 is increased by the four portions 9 formed on the lower magnetic pole 3 and the lower insulating layer 4 filled in the recesses 6-9. As shown in FIG. 7, the spacing λ between the upper and lower magnetic poles 3 and 8 can be made as large as possible without having to do so.

Therefore, the distance between upper and lower F11 poles 3 and 8 is 111t/! , can be separated without causing an increase in magnetic resistance, thereby effectively reducing leakage magnetic flux, and improving recording/reproducing efficiency.

Moreover, by forming the recess 9 and filling the lower insulating layer 4 whose upper surface is in the same horizontal plane as the flat part 10 of the lower magnetic pole 3,
Since the coil 6 can be formed using photolithography on a flat surface with no steps, it is possible to improve the conventional problem of exposing unnecessary parts due to steps, and as a result, photolithography It is now possible to form a coil 6 with a fine pattern by dramatically increasing the accuracy of the process, and the problems of the conventional method including leakage magnetic flux can be solved.

In the first embodiment described above, the present invention was applied to a thin film magnetic head in which the gap layer 5 was formed on the lower insulating layer 4, but as in the second embodiment shown in FIG. The present invention may also be applied to a thin film magnetic head in which a gap layer 5 is formed on top of the gap layer 5.

〔Effect of the invention〕

As explained above, according to the present invention, the distance between the upper and lower magnetic poles can be reduced without increasing the step portion of the upper magnetic pole, and the coil can be formed on a plane with no step (
(formation by photolithography).

Therefore, it is possible to improve recording/reproducing efficiency by reducing leakage magnetic flux without increasing magnetic resistance, and it is also possible to improve the precision of photolithography and easily form coils with fine patterns. to Qin.

[Brief explanation of drawings]

1 to 3 show a first embodiment of this invention,
Fig. 1 is a cross-sectional view showing a thin film magnetic head, Fig. 2(a) -
(f) is a plan view showing the formation of the recess of the lower magnetic pole and the lower insulating layer formed in the recess along the manufacturing process of the thin film magnetic head, and Fig. 3 shows the upper and lower magnetic poles of the thin film magnetic head. FIG. 4 is an enlarged cross-sectional view showing a state where the gap is separated; FIG. 4 is a cross-sectional view showing a thin film magnetic head according to a second embodiment of the present invention;
8 shows a conventional thin film magnetic head, FIG. 5 is a sectional view of the thin film magnetic head, FIG. 6 is a plan view thereof, and FIG. 7 is a sectional view of the thin film magnetic head.
The figure is a cross-sectional view showing the details between the upper and lower magnetic poles, and FIG. 8 is a cross-sectional view showing the state of coil formation by photolithography. 3... Lower magnetic pole, 4... Lower insulating layer, 6... Coil,
7... Upper insulating layer, 9... Concave portion, 10... Flat portion. Applicant's representative Patent attorney Jun Tsuboi Figure 1 Figure 7 Figure 8

Claims (1)

[Claims] A thin film magnetic head comprising a coil sandwiched between a lower insulating layer and an upper insulating layer between a lower magnetic pole and an upper magnetic pole. 1. A thin film magnetic head comprising a flat portion, and the lower insulating layer is disposed within the recess so that its upper surface is in the same horizontal plane as the flat portion.