JPH01220210A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To prevent magnetic efficiency from being lowered by forming a lower magnetic layer so that the joining plane of the lower magnetic layer with an upper magnetic layer can approach the upper magnetic layer. CONSTITUTION:A prismatic layer 12 is provided so that the joining plane of the lower magnetic layer 3 with the upper magnetic layer 10 can approach the upper magnetic layer 10. Here, in case of applying photoresist to form the upper magnetic layer 10, the photoresist attached on the inclined plane of a dent drops on the bottom part of the dent, however, since the depth of the dent becomes shallow and the area of the inclined plane is reduced by forming a prismatic layer 7 on a substrate 1 and a protecting insulation layer 2 in the dent, it is possible to form the thickness of the photoresist layer formed on the bottom part of the dent almost in the same thickness as that of another photoresist layer. Therefore, an ultraviolet ray can arrive at the bottom part of the photoresist layer, and the photoresist layer is welded completely, and when the upper magnetic layer 10 is formed, it is possible to prevent the photoresist from remaining at the joining part of the upper magnetic layer 10 with the lower magnetic layer 3. In such a way, the magnetic efficiency can be prevented from being lowered.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a thin film formed using a photoresist used in a magnetic recording/reproducing device that reads data from a magnetic recording medium and writes data to a magnetic recording medium. This relates to magnetic heads.

Conventional technology FIG. 5 is a side sectional view showing a conventional thin film magnetic head.

In FIG. 5, 1 is a substrate, 2 is a protective insulating layer formed on the substrate 1, 3 is a lower magnetic layer formed on the protective insulating layer 2 and made of a magnetic material, and 4 is a magnetic gap. The gap insulating layer 4 is formed on the lower magnetic layer H3 except for the end of the lower magnetic layer 3 on the side opposite to the surface facing the magnetic recording medium. 5 is an interlayer insulating layer formed on the gap insulating layer 4; 6 is a coil layer formed on the glabella insulating layer 5 and generates magnetic flux; 7 is an interlayer insulating layer formed on the coil layer 6; 8; is a coil layer formed on the interlayer insulating layer 7, 9 is an interlayer insulating layer formed on the coil layer 8, and 10 is an upper magnetic layer formed on the interlayer insulating layer 9 and made of a magnetic material. The upper magnetic layer 10 is joined to the end of the lower magnetic layer 3 on the side opposite to the medium facing surface to form a magnetic circuit including a magnetic gap. Further, the lower magnetic layer 3 and the upper magnetic layer 1 around which the coil layers 6 and 8 are wound
The film thickness of the 0 portion is increased to reduce magnetic resistance. 11 is a protective insulating layer formed on the upper magnetic layer 10.

The manufacturing process of the conventional thin film magnetic head constructed as described above will be explained with reference to FIGS. 6 to 13.

First, as shown in FIG. 6, a protective insulating layer 2 is formed on a substrate 1. Next, a lower magnetic layer 3 is formed on the protective insulating layer 2 until it reaches the surface facing the magnetic recording medium. Next, as shown in FIG. 7, a gap insulating layer 4 is formed except for the end of the lower magnetic layer 3 on the side opposite to the medium facing surface. At this time, the gap insulating layer 4 is formed on the lower magnetic layer 3 until it reaches the medium facing surface, except for the end of the lower magnetic layer 3 on the side opposite to the medium facing surface, and the rest is provided with protective insulation. Formed on layer 2. Thereon, an interlayer insulating layer 5 is formed as shown in FIG. At this time, the end of the interlayer insulating layer 5 on the medium facing surface side is formed at a position a certain distance away from the medium facing surface. A coil layer 6 made of a conductive thin film is formed thereon as shown in FIG. An interlayer insulating layer 7 is formed thereon to cover the coil layer 6 as shown in FIG. 10, a coil layer 8 is formed thereon as shown in FIG.
As shown in Figure 2, an interlayer insulating layer 9 is formed to cover the coil layer 8.
form. Using 7 otoresist on top of that, 13th
As shown in the figure, the upper magnetic layer 10 is formed, and the upper magnetic layer 10
The end opposite to the medium facing surface is joined to the lower magnetic layer 3 so as to form a magnetic circuit including a magnetic gap together with the lower magnetic layer 3. A protective insulating layer 11 is formed on the father magnetic layer 10.

Problems to be Solved by the Invention However, in the conventional structure, when photoresist is coated on the interlayer insulating layer 9 to form the upper magnetic layer 10 as shown in FIG. 12, the coil layer 6 shown in FIG. , 8 and the interlayer insulating layer 5°7.9, the photoresist coated on the slope of the depression flows into the bottom of the depression, so when the photoresist is dried to form a photoresist layer, the surface of the depression is The photoresist layer is thicker at the bottom, covered with a photomask, and irradiated with ultraviolet light. Next, in the step of dissolving the photoresist irradiated with ultraviolet rays with a developer, the photoresist layer in the depressions is thicker than in other parts, so the photoresist in the depressions does not dissolve in the developer. By remaining the upper magnetic layer 1
0, the bottom of the recess, which is the joint surface between the upper magnetic layer 10 and the lower magnetic layer 3, may not be formed (the upper magnetic layer 10 may not be formed, or the joint between the lower magnetic layer 3 and the upper magnetic layer 10 may not be formed). When the photoresist gets into the recess, the magnetic resistance increases and the magnetic efficiency of the thin film magnetic head decreases.Also, the photoresist layer formed at the bottom of the recess is completely soluble in the developer. In order to do this, the intensity of the ultraviolet rays must be increased or the exposure time must be increased, which has the problem of not improving productivity.

The present invention solves the above-mentioned conventional problems, and prevents the photoresist layer formed in the recess where the upper magnetic layer and the lower magnetic layer are joined from being thicker than other parts, It is an object of the present invention to provide a thin film magnetic head that can prevent a decrease in magnetic efficiency of the thin film magnetic head.

Means for Solving the Problems In the present invention, in order to solve the conventional problems, the lower magnetic layer is formed so that the joint surface of the lower magnetic layer with the upper magnetic layer is brought closer to the upper magnetic layer.

Function: With this configuration, the depth of the magnetic layer junction where the upper magnetic layer and the lower magnetic layer are joined can be made shallow, and the width of the inclined surface of the magnetic layer junction can be reduced.

Embodiment FIG. 1 is a side sectional view showing a thin film magnetic head in an embodiment of the present invention. 1 is a substrate, 2 is a protective insulating layer, 3 is a lower magnetic layer, 4 is a gap insulating layer, 5 is an interlayer insulating layer, 6 is a coil layer, 7 is an interlayer insulating layer, 8 is a coil layer, 9 is an interlayer insulating layer, 10 is an upper magnetic layer, and 11 is a protective insulating layer, which are the same as the conventional structure. 12 is a columnar layer formed on the substrate 1, and the columnar layer 12 is the upper magnetic layer 10 of the lower magnetic layer 3.
The upper magnetic layer 1o is provided in such a manner that its bonding surface with the upper magnetic layer 1o is close to the upper magnetic layer 1o.

FIG. 2 is a side sectional view showing a thin film magnetic head in a second embodiment of the invention. 13 is a columnar layer formed on the protective magnetic layer 2, and the columnar layer 13 is the upper magnetic layer 1 of the lower magnetic layer 3.
0 is provided so that the bonding surface with the upper magnetic layer 10 is brought closer to the upper magnetic layer 10.

FIG. 3 is a side sectional view showing a thin film magnetic head in a third embodiment of the present invention. 14 is a columnar layer provided on the substrate 1; 15 is a columnar layer formed on the columnar layer 14 via the protective insulating layer 2; the columnar layers 14 and 15 are the upper magnetic layer 10 of the lower magnetic layer 3; The bonding surface of the upper magnetic layer 10 is placed close to the upper magnetic layer 10.

FIG. 4 is a sectional view showing a fourth embodiment of the present invention. 1
6 is a columnar layer formed of a non-magnetic insulating material on the substrate 1, and the protective insulating layer 2 is not formed on the columnar layer 16.

Further, the columnar layer 16 is provided so as to be close to the upper magnetic layer 10 of the lower magnetic layer 3.

As described above, according to these embodiments, when a photoresist is applied to form the upper magnetic layer 10, the photoresist adhering to the sloped surface of the recess flows down to the bottom of the recess, but the substrate 1 and the protective layer are coated in the recess. By forming a columnar layer on the insulating layer 2, the depth of the depression becomes shallow (and the area of the slope surface decreases, so the thickness of the photoresist layer formed at the bottom of the depression becomes smaller than that of other photoresists). Since the thickness can be made almost the same as the thickness of the photoresist layer, it is possible to allow the ultraviolet rays to reach the bottom of the photoresist layer formed in the recesses, without increasing the intensity of the ultraviolet rays or lengthening the exposure time. When developed with a developer, the photoresist layer formed in the recess is completely dissolved, so that when the upper magnetic layer 10 is formed, no photoresist remains at the junction between the upper magnetic layer 10 and the lower magnetic layer 3. In addition, although the columnar layer was formed on the substrate 1 in the first and fourth embodiments, the columnar layer may be formed integrally with the substrate.

Effects of the Invention The present invention has the advantage that by forming the lower magnetic layer so that the bonding surface of the lower magnetic layer with the upper magnetic layer approaches the upper magnetic layer, the depth of the recess where the upper magnetic layer and the lower magnetic layer bond can be reduced. When a photoresist is applied to form the upper magnetic layer, it is possible to reduce the width of the inclined surface of the recess.
The thickness of the photoresist layer formed at the junction between the upper magnetic layer and the lower magnetic layer can be made to be about the same thickness as the other photoresist layers, and the thickness of the photoresist layer formed at the junction between the upper magnetic layer and the lower magnetic layer can be Since it is possible to prevent the residual amount of the magnetic flux from remaining, it is possible to prevent an increase in the magnetic resistance of the joint portion and a decrease in the magnetic efficiency of the thin-film magnetic head.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing a thin film magnetic head in a first embodiment of the present invention, FIG. 2 is a side sectional view showing a thin film magnetic head in a second embodiment of the invention, and FIG. 3 is a side sectional view showing a thin film magnetic head in a second embodiment of the invention. 4 is a side sectional view showing a thin film magnetic head in a fourth embodiment of the present invention, and FIG. 5 is a side sectional view showing a conventional thin film magnetic head. 6 to 13 are side sectional views showing a conventional method of manufacturing a magnetic head. 1...Substrate 2...Protective insulating layer 3...Lower magnetic layer 4...Gap insulating layer 5.7.9...Interlayer Insulating layer 6.8...Coil layer 10...Top magnetic layer 11...Protective insulating layer 12.13, 13.15...Column layer agent Name: Patent attorney Toshio Nakao
Castle diagram 6

Claims (1)

[Claims] a substrate, a protective insulating layer formed on the substrate, a lower magnetic layer formed on the protective insulating layer, a gap insulating layer formed on the lower magnetic layer and serving as a magnetic gap; a coil layer formed on the gap insulating layer with an insulating layer interposed therebetween to generate magnetic flux; and a coil layer formed on the coil layer with an insulating layer interposed therebetween, forming a magnetic circuit including the magnetic gap together with the lower magnetic layer. 1. A thin film magnetic head comprising an upper magnetic layer, the lower magnetic layer being formed such that a bonding surface of the lower magnetic layer with the upper magnetic layer approaches the upper magnetic layer.