JPH04195711A - Thin film magnetic head - Google Patents

Abstract

PURPOSE:To protect an upper magnetic layer from etching when the upper magnetic layer and a lower magnetic layer are successively etched by a method wherein an etching protection film is formed between the upper magnetic layer and a resist film. CONSTITUTION:An etching protection film 18 if formed on an upper magnetic layer 12 and, further, a resist film 16 is built up. Although the etching protection film 18 is formed above coil conductors 22 from the right part to the upper half of the tapered part 28 in the figure, it is not necessary to limit the etching protection film 18 in this region. The etching protection film 18 must be formed at least on the parts (especially the tapered part 28) of the upper magnetic layer 12 which would be etched unless the etching protection film 18 were formed. Further, the etching protection film 18 may be formed over the whole surface if it is limited within a region which is not exposed on a medium facing surface and does not give influence upon magnetic characteristics. With this constitution, the upper magnetic layer 12 is protected from etching and harmful influence upon the magnetic circuit can be avoided.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a thin film magnetic head having a lower magnetic layer and an upper magnetic layer sandwiching a gap layer on a medium facing surface, and particularly to a thin film magnetic head compatible with narrow tracks.

[Conventional technology]

In recent years, magnetic heads used in magnetic disk devices, etc.
Progress has been made to increase the recording density and efficiency of magnetic disk media, and their shapes are becoming smaller and more precise. In response to these demands, various types of compact thin-film magnetic heads have already been proposed and put into practical use, which have a steep head magnetic field distribution at the tip of the magnetic pole that contributes to recording and enable high-density recording. FIG. 3 is a diagram of a part of a conventional thin film magnetic head viewed from the medium facing surface side. The lower magnetic layer 14 and the upper magnetic layer I sandwich the gap layer IO.
2 is formed. In this thin film magnetic head, the upper track width t1 of the upper magnetic layer 12 is smaller than the lower track width t of the lower magnetic layer 14. In recent years, as the track density of magnetic recording media has increased, there has been a demand for smaller track widths and smaller track-to-track distances. However, as in the conventional thin-film magnetic head, the lower track width t is 1.5 mm above the upper trough width. If it is larger than , leakage of magnetic flux will occur, which will cause noise generation. Therefore, the upper track width and the lower track width. It is preferable that the sizes of the two be the same as possible as shown in FIG. As shown in FIGS. 5 and 6, a resist film 16 is formed on the upper magnetic layer 12 by spin-coating as a mask material, and then a cap layer is formed when the upper magnetic layer I2 is etched with an ion beam. It can be formed by etching 10 and the lower magnetic layer 14.

[Problem to be solved by the invention]

However, if the Lenost film 16 is applied using a spin code to the tapered portion 28 with a step E of about 10 μm, the film thickness at the shoulder of the step of the upper magnetic layer 12 becomes thinner, and etching is carried out in this state for a long time. When the resist film I6 is etched from the line R1 to the line R2, the portion A of the upper magnetic layer 12 is etched, which adversely affects the magnetic circuit of the thin film magnetic head. Furthermore, as long as the resist film I6 is applied using a spin code, it is extremely difficult to increase the thickness of the resist film 16. The present invention has been made to solve the problem of surface writing,
Dobe's purpose is to provide a thin film magnetic head that protects the upper magnetic layer from etching by forming an etching protection film on at least the parts of the magnetic layer that are likely to be etched before applying the resist film. do.

[Means to solve the problem]

In order to solve the above problems, the present invention has a structure in which a lower insulating layer, a lower magnetic layer, a cap layer, a coil conductor covered with an interlayer insulating layer, and an upper magnetic layer are laminated on a substrate, and further the upper A thin film magnetic head comprising a Lennost film formed on a magnetic layer, characterized in that an etching protection film is formed between the upper magnetic layer and the Lennost film.

[Effect]

The thin film magnetic head of the present invention protects the upper magnetic layer from etching when the upper magnetic layer and the lower magnetic layer are sequentially etched by forming an etching protection film behind the upper magnetic layer and the Lenost film. It is something that can be done. Furthermore, since the upper magnetic layer and the lower magnetic layer can be etched at the same time, the track width of the upper magnetic layer and the track width of the lower magnetic layer can be made the same, eliminating noise caused by leakage of magnetic flux. As for the track width, the width between tracks can be reduced, and a thin film magnetic head suitable for high-density recording can be obtained. This etching protection film preferably has a low etching rate in ion beam etching and can be etched without etching the magnetic layer when etching the etching protection film, and suitable materials include C and Ti.

【Example】

1 and 2 show one embodiment of the present invention. The thin film magnetic head of the present invention includes a substrate 24, a lower insulating layer 2
6, a lower magnetic layer 14, a gap layer 10, a coil conductor 22 covered with an interlayer insulating layer 20, and an upper magnetic layer 12.
It is made up of layers. Furthermore, an etching protection film 18 is formed on the upper magnetic layer 12, and a Renost film 16 is further laminated thereon. As shown in the figure, the etching protection film 18 is formed from the right side over the coil conductor 22 to about the upper half of the tapered part 28, but is not limited to this, and there is a possibility that at least the upper magnetic layer 12 may be etched. The upper magnetic layer 12 is formed in a certain location (particularly the tapered portion 28) and covers almost the entire upper magnetic layer 12 as long as it is not exposed to the medium facing surface and does not affect the magnetic performance. It doesn't matter if it's something. In manufacturing a thin film magnetic head, a number of steps including chip slicing, polishing, assembly, etc. are performed, and an example of one of these steps will be described below. A lower insulating layer 26 (A ItO3, 5io
etc.), a ferromagnetic material such as permalloy or sendust is sputtered on the upper surface of the lower magnetic layer 14, and a gap layer 10 is further formed by sputtering A 1103.5 io or the like. Next, aluminum (A I), copper (Cu), etc. are formed by vapor deposition or sputtering, and the coil conductor 22 is formed by dry etching.
2 is encapsulated and flattened. Furthermore, the glabellar insulating layer 20 is etched into a predetermined shape and removed. Then, on the surface of the H-interval insulation N20,
The upper magnetic layer 12 is formed by sputtering Permalloy, Sendust, or the like. An etching protection film 18 is formed on a predetermined portion of the upper surface. This etching protection film 18 has a low etch rate in ion beam etching, and when etching this etching protection film 18, it is preferable to use a film that can be etched without etching the magnetic layer.
and Ti are suitable materials. Furthermore, a resist film 16 is laminated over the entire upper magnetic layer 12 and etching protection film 18 using a spin code. Thereafter, as shown in FIG. 5, the resist film 16, the upper magnetic layer 12, the gap layer IO, and the lower magnetic layer 1i14 are etched to a predetermined core shape with an ion beam up to Rtta in FIG. 1. Thus, the upper track width 11 as shown in FIG.
and the lower track width t are almost equal in length, suppressing the generation of noise due to leakage of magnetic flux, and making it possible to manufacture a thin film magnetic head that can accommodate narrow track widths and narrow track-to-track widths. According to the thin film magnetic head of the present invention, since the etching protection film I8 is formed, the upper magnetic layer 12 is not attacked during etching, and the magnetic circuit is not adversely affected.

【Effect of the invention】

As explained above, the thin film magnetic head of the present invention has an etching protection film formed on the upper magnetic layer and a Lenost film laminated thereon. Even if the upper magnetic layer disappears, the etching of the track can be completed without etching the upper magnetic layer, and the magnetic circuit is not adversely affected. Furthermore, in the thin film magnetic head of the present invention, since the upper magnetic layer and the lower magnetic layer can be etched at the same time, the track width of the upper magnetic layer and the track width of the lower magnetic layer can be made the same, which reduces the magnetic flux. The thin film magnetic head is suitable for high-density recording because the track width or track-to-track width can be reduced without generating noise due to leakage.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the thin-film magnetic head of this embodiment, FIG. 2 is a plan view of the same thin-film magnetic head, and FIG. 3 is a partial view of a conventional thin-film magnetic head viewed from the medium facing surface side. , FIG. 4 shows a part of an ideal thin-film magnetic head on its medium-facing surface J.
5 is a partial view of a thin film magnetic head seen from the medium facing surface side, showing a manufacturing method that makes the upper track width and lower track width the same, and FIG. 6 is a view of a conventional thin film magnetic head. FIG. 3 is a cross-sectional view of a magnetic head. 10 gap layer, 12 upper magnetic layer, 14 lower magnetic layer, 16 resist film, 18 etching protection film, 20 interlayer insulating layer, 22 coil conductor, 24 substrate, 26 lower insulating layer, tl upper track width, [, lower track width .

Claims (1)

[Claims] A lower insulating layer, a lower magnetic layer, a gap layer, a coil conductor covered with an interlayer insulating layer, and an upper magnetic layer are laminated on the substrate, and a resist film is further formed on the upper magnetic layer. 1. A thin film magnetic head, characterized in that an etching protection film is formed between the upper magnetic layer and the resist film.