JP2982634B2 - Manufacturing method of horizontal thin film magnetic head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film magnetic head used for a magnetic printing apparatus and a magnetic recording apparatus, and more particularly to a method for manufacturing a horizontal thin film magnetic head.

[0002]

2. Description of the Related Art As a magnetic head for a magnetic printing apparatus, a magnetic head generally used for a magnetic recording apparatus such as a magnetic disk can be used. Various types of horizontal thin-film magnetic heads have been researched and developed instead of magnetic heads.

FIG. 3A is a plan view of a conventional horizontal thin-film magnetic head, and FIG. 3B is a sectional view of the head.
1 is a magnetic substrate serving as a lower magnetic core, 12 is a coil made of a conductor, 13 is an insulating film for insulating the coil 12, 1
4 is a gap film for forming a gap in the magnetic core,
Reference numeral 16 denotes an upper magnetic film serving as an upper magnetic core.

In the thin-film magnetic head of FIG. 3, a coil 12, an insulating film 13, a gap film 14, and an upper magnetic film 16 are sequentially formed on a magnetic substrate 11 serving as a lower magnetic core by a thin-film forming process. As a result, the upper magnetic film 1
6, a magnetic gap is formed by the gap film 14 at the center. Such a horizontal thin-film magnetic head can reduce the ratio of the gap length to the magnetic path length of the core as compared with the vertical thin-film magnetic head. It has the advantage that power consumption can be reduced.

The horizontal thin-film magnetic head is manufactured by forming a magnetic material such as CoZr to be the upper magnetic film 16 on the insulating film 13 including the gap film 14 by an evaporation method such as sputtering. The surface of the magnetic film 16 is polished to complete the process.

Here, the gap film 14 usually has a rectangular cross section as shown in FIG. Due to the steep structure of this rectangular shape, in the process of forming the upper magnetic film 16 by using a vapor deposition method such as sputtering, the gap material 14 is formed before the magnetic material increases in thickness on the insulating film 13. Phenomenon occurs on the side surface of the substrate. As a result, the upper magnetic film 16 is
May be formed in a shape like

Since streaks or gaps are formed in the upper magnetic film 16 formed as shown in FIG. 4, when the upper magnetic film 16 is polished to obtain a final head, the shape shown in FIG. The mechanical strength decreases due to the generation of the gap, and the magnetic characteristics decrease due to the increase in the magnetic resistance.

[0008]

Since a thin film is formed in the conventional horizontal thin film magnetic head as described above, a gap is formed in the upper magnetic film near the gap film when the upper magnetic film is formed. There is a problem that the mechanical strength is reduced due to the generation of the gap and the magnetic characteristics are reduced due to the increase in the magnetic resistance, and the performance of the horizontal thin-film magnetic head is reduced. An object of the present invention is to provide a method of manufacturing a horizontal thin-film magnetic head capable of forming an upper magnetic film without deteriorating mechanical strength and magnetic properties in order to solve the above-mentioned problems.

[0009]

According to the present invention, there is provided a step of forming a coil on a lower magnetic core, a step of forming an insulating film on the coil, and setting a total height of a gap film on the insulating film. Forming a gap-forming film thicker than a value obtained by adding a first predetermined value for setting a size of a curved surface formed on both lower sides of the gap film to the gap. Forming a gap forming mask on the gap forming film such that the film is exposed on both sides with a width smaller than that of the forming film, and using the gap forming mask as a mask to set the gap forming film to a first predetermined value; Forming a gap film having a curved surface by removing the mask for forming a gap and wet-etching the film for forming a gap by a thickness of a second predetermined value. Gya Forming an upper magnetic film serving as an upper magnetic core on the insulating film including the film, and polishing the upper magnetic film until the gap film is exposed. The shape is such that the width increases toward.

[0010]

According to the present invention, the gap forming film is anisotropically etched by a first predetermined thickness using the gap forming mask as a mask, and the gap forming mask is removed to remove the gap forming film. By performing wet etching by the thickness of the second predetermined value, an arc-shaped curved surface having a radius of the second predetermined value is formed on both lower sides of the gap film. The shape can be such that the width is large.

[0011]

1 and 2 are sectional views of a horizontal thin-film magnetic head according to an embodiment of the present invention. 1 is ferrite,
A magnetic substrate serving as a lower magnetic core made of a magnetic material such as Permalloy or CoZr, a coil 2 made of a conductor such as Al or Cu having a thickness of 2 μm, and a insulator 3 made of SiO 2, resist or polyimide having a thickness of 6 μm. The insulating film 4 is formed of a non-magnetic material such as SiO2 for forming a gap film 4a serving as a gap between the magnetic cores.

Reference numeral 5 denotes a mask made of a metal such as CoZr, 5a denotes a gap forming mask formed by processing the mask 5, and 6 denotes an upper magnetic core made of a magnetic material such as ferrite, permalloy, or CoZr. Is the upper magnetic film. Reference numeral 7 denotes a contact hole which is formed at the center of the coil 2 and magnetically connects the magnetic substrate 1 and the upper magnetic film 6 to form a magnetic circuit.

This embodiment shows an example in which an insulating magnetic material is used for the magnetic substrate 1. Therefore, the coil 2, which is a conductor, is formed directly on the magnetic substrate 1. When a magnetic material having a property is used, the coil 2 is formed after forming an insulating film on the magnetic substrate 1.

Next, a method of manufacturing such a horizontal thin-film magnetic head will be described. First, a 2 μm-thick
A conductor such as Al or Cu is formed by a vapor deposition method such as sputtering, and is ion-etched (hereinafter referred to as RIE), and the pattern of the coil 2 shown in FIG. It is formed in a pattern that is wound around a magnetic core made of the upper magnetic film 6.

Next, a thickness 6
An insulating film 3 of μm is formed. At this time, when SiO2 is used as the material of the insulating film 3, a film is formed by a P-CVD method or a sputter deposition method, and is etched by RIE to form a pattern as shown in FIG. When a resist or polyimide is used, it is applied by spin coating or the like, and is exposed and developed, or is similarly patterned by RIE. The steps so far are the same as those of the conventional horizontal thin-film magnetic head shown in FIG.

Next, as shown in FIG.
The film thickness (14 μm in the present embodiment) of the gap forming film 4 made of P is formed by a P-CVD method or a sputter deposition method to a first predetermined value (10 μm in the present embodiment) for setting the overall height of the gap film 4 a. ) And a second predetermined value (at least 2 μm in this embodiment) for setting the size of the curved surface 4b formed on both lower sides of the gap film 4a.

Then, C is formed on the gap forming film 4.
After forming a mask 5 made of oZr or the like, the film 4 in the portion of the contact hole 7 is etched by RIE to about 30% of the film thickness to form a shape as shown in FIG. The gap forming film 4 on the contact hole 7 may be entirely removed in this step. However, what is left as described above is that if the film 4 is etched 100% here, the magnetic substrate 1 This is because the surface becomes rough.

Next, the mask 5 is processed into a gap forming mask 5a having a shape as shown in FIG. 1D by wet etching or the like, and the exposed gap forming film 4 is formed to a first predetermined value. Etch only the thickness by RIE,
It is processed into a shape as shown in FIG.

Then, the mask 5 and the gap forming mask 5a are completely removed by wet etching.
When wet etching with a solution such as F: ammonium fluoride = 12: 100 (volume ratio) is performed for a second predetermined thickness, the total height becomes substantially the first predetermined value as shown in FIG. A gap film 4a is formed, and an arc-shaped curved surface 4b having a radius of a second predetermined value is formed on both lower sides of the gap film 4a.
Is formed.

It is desirable that the gap forming film 4 be completely removed except for the gap film 4a. However, the gap forming film 4 is formed on the insulating film 3 except for the gap film 4a.
May remain. Next, as shown in FIG. 2, a magnetic material CoZr to be the upper magnetic film 6 is deposited by RF magnetron sputtering so as to have a thickness equal to or greater than the entire height of the gap film 4a.
Here, the cross-sectional shape of the gap film 4a has a shape in which the width (the left-right direction in FIGS. 1 and 2) increases downward due to the curved surface 4b. However, the film is formed without a gap, and is not formed as shown in FIG.

After the upper magnetic film 6 is patterned by etching, if the surface is polished until the gap film 4a is exposed, it becomes a shape similar to that shown in FIG. 3B, and the wafer process of the horizontal thin film magnetic head is completed. I do. As described above, it is possible to realize a horizontal thin-film magnetic head in which no gap is formed in the upper magnetic film 6 near the gap film 4a. In the head manufactured in this manner, the magnetic flux is concentrated on the upper surface of the gap film 4a, so that the magnetic characteristics can be improved.

In this embodiment, the gap forming film 4 is used.
Is used, but the same gap film can be formed with a resin material such as a resist or polyimide by changing the conditions such as the gas for RIE and the solution for wet etching.

In the present invention, since the wet etching is used in the final step of forming the gap film 4a (FIG. 1E), the surface of the gap film 4a is formed more than when the gap film is formed by dry etching. Is smoothed, and the surface of the upper magnetic film 6 formed on the gap film 4a is also smoothed, so that a horizontal thin-film magnetic head having excellent magnetic characteristics can be realized. Further, since the gap film 4a having the rectangular section and the curved surface 4b is formed integrally, there is no reduction in mechanical strength as in the case where the rectangular portion and the curved surface are formed separately.

[0024]

According to the present invention, the gap forming film is anisotropically etched by a first predetermined thickness using the gap forming mask as a mask, and the gap forming mask is removed by removing the gap forming mask. The film is wet-etched by a second predetermined thickness to form curved surfaces on both lower sides of the gap film, so that the cross-sectional shape of the gap film is shaped to increase in width downward. So you can
An upper magnetic film without any gap can be formed near the gap film, and a horizontal thin-film magnetic head having excellent mechanical strength and magnetic properties can be realized. Further, since the radius of the circular arc of the curved surface has the second predetermined value, the size of the curved surface can be freely controlled by the second predetermined value.

[Brief description of the drawings]

FIG. 1 is a process sectional view of a horizontal thin-film magnetic head showing one embodiment of the present invention.

FIG. 2 is a process sectional view of a horizontal thin-film magnetic head showing one embodiment of the present invention.

FIG. 3 is a plan view and a sectional view of a conventional horizontal thin-film magnetic head.

FIG. 4 is a cross-sectional view showing the vicinity of a gap film after forming an upper magnetic film in a conventional horizontal thin-film magnetic head.

FIG. 5 is a cross-sectional view of the horizontal thin-film magnetic head of FIG. 4 after the surface of an upper magnetic film is polished.

[Explanation of Symbols] 1 ... magnetic substrate (lower magnetic core), 2 ... coil, 3 ... insulating film, 4 ... gap forming film, 4a ... gap film, 4b ...
Curved surface, 5 ... mask, 5a ... gap forming mask, 6 ...
Upper magnetic film, 7 ... contact hole.

Claims (1)

(57) [Claims] 1. A step of forming a coil on a lower magnetic core, a step of forming an insulating film on the coil, and a first predetermined value for setting a total height of a gap film on the insulating film. Forming a gap-forming film thicker than a value obtained by adding a second predetermined value for setting the size of a curved surface formed on both lower sides of the gap film; Forming a gap-forming mask on the gap-forming film so that the film is exposed by anisotropic etching, and anisotropically etching the gap-forming film by a first predetermined thickness using the gap-forming mask as a mask. Removing the gap-forming mask, wet-etching the gap-forming film by a second predetermined thickness to form a gap film having the curved surface, and forming a gap film having the curved surface on the insulating film including the gap film. Forming an upper magnetic film serving as an upper magnetic core, and polishing the upper magnetic film until the gap film is exposed, wherein the curved surface increases the width of the cross-sectional shape of the gap film downward. What is claimed is: 1. A method for manufacturing a horizontal thin-film magnetic head, comprising: