JPH06103523A - Production of thin-film magnetic head - Google Patents

Abstract

PURPOSE:To produce the thin-film magnetic head which is small in the etching amt. of the insulating film on a conductor coil layer on the periphery of an upper magnetic core and has high processing accuracy of a front end. CONSTITUTION:A lower magnetic material layer 12, a magnetic gap layer 13, the conductor coil layer 14 and the insulating layer 15 are formed on a substrate 11 and thereafter, an upper magnetic material layer 16 is formed. A first mask layer 7 is then so formed on this upper magnetic material layer 16 as to expose the upper magnetic material layer of a prescribed region in the front end region of a magnetic yoke having a gap for conversion. The material of the exposed region is then selectively etched to form the front end of the magnetic yoke of a prescribed shape. After the stage for removing the first mask layer 17, a second mask layer 18 for protecting the front end of the magnetic yoke and forming the magnetic yoke shape in the part exclusive of the front end of the magnetic yoke is formed. The exposed upper magnetic layer 16 is selectively removed. The second mask layer 18 is then removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a magnetic recording device, for example,
The present invention relates to a method for manufacturing a thin film magnetic head mounted on a magnetic disk device or a magnetic tape device, and particularly to a method for manufacturing an upper magnetic core.

[0002]

2. Description of the Related Art The shape of the magnetic core of a thin film magnetic head has a great influence on the recording / reproducing characteristics, and therefore must be processed with high precision. The magnetic core of the thin film magnetic head is formed by forming a magnetic layer by a method such as sputtering or vapor deposition, and using a mask material such as photoresist, dry etching means such as sputter etching or ion beam etching to remove the portion other than the mask portion. Form by removing. Regarding this manufacturing method,
For example, JP-A-58-88815 and JP-A-58-88815.
It is disclosed in the publication.

[0003]

An insulating layer is provided below and near the upper magnetic core of the thin film magnetic head, and a conductor coil layer is embedded in the insulating layer. When the upper magnetic layer is formed by dry etching means such as ion beam etching, the insulating layer, which is a lower layer of the upper magnetic layer, is also etched by over-etching. In general, 20% to 50% of the just etching time (the time during which the magnetic layer is almost etched) is added as the overetching time in order to obtain processing accuracy and to prevent etching residue. . As the film thickness of the upper magnetic layer becomes thicker, the over-etching time also becomes longer, so that the insulating layer is etched a lot and the conductor coil is exposed and etched. To avoid etching this conductor coil,
The thickness of the insulating layer on the conductor coil layer needs to be thicker than the original purpose in consideration of over-etching when etching the upper magnetic layer. As a result, the element height becomes high, and there are problems such as a reduction in processing accuracy at the tip of the magnetic core and a reduction in yield due to non-uniformity of the insulating film shape.

The prior art does not disclose a method of manufacturing a thin film magnetic head in consideration of etching of an insulating film when forming an upper core.

An object of the present invention is to provide a method of manufacturing a thin film magnetic head in which the etching amount of the insulating film on the conductor coil layer around the upper magnetic core is small and the processing accuracy of the tip portion can be obtained.

[0006]

A thin film magnetic head manufactured according to the present invention comprises a lower magnetic layer, a magnetic gap layer, a conductor coil layer, and an insulating layer for insulating the conductor coil from the upper and lower magnetic layers on a substrate. , And an upper magnetic layer are laminated, and the structure has a yoke structure having a conversion gap at one end and a rear gap region at the other end.

A method of manufacturing a thin film magnetic head according to the present invention comprises a lower magnetic layer, a magnetic gap layer, a conductor coil layer,
And a step of forming the upper magnetic layer in the magnetic gap layer, the insulating layer, and the rear gap region exposed at least on the substrate after forming the insulating layer, and forming a conversion gap on the upper magnetic layer. A step of forming a first mask layer so that the upper magnetic layer in a predetermined region is exposed in a magnetic yoke tip region, and a magnetic yoke having a predetermined shape by selectively etching a material in the exposed region. A step of forming a tip portion, a step of removing the first mask layer, and a second mask layer for protecting the magnetic yoke tip portion and forming a magnetic yoke shape of a portion other than the magnetic yoke tip portion. The method includes a forming step, a step of selectively removing the exposed upper magnetic layer, and a step of removing the second mask layer.

The upper magnetic layer is preferably formed by a sputtering method, a vapor deposition method or the like.

The magnetic yoke tip region in the step of forming the first mask layer is preferably in front of the conductor coil layer.

As a method for selectively removing the upper magnetic layer, an ion beam etching method, a sputter etching method or the like is used when the first mask layer is used, and a chemical etching is used when the second mask layer is used. Is desirable. This is because the magnetic yoke tip region requires processing accuracy, and the rear region requires selectivity with the insulating layer rather than processing accuracy.

As a method of selectively removing the upper magnetic layer, when the same method is used in the step of using the first mask layer and the step of using the second mask layer, the overetching time is It is desirable that the step of using the second mask layer be shorter than the step of using one mask layer.

According to the method of manufacturing a thin film magnetic head of the present invention, after the lower magnetic layer, the conductor coil layer and the insulating layer are formed on the substrate, the magnetic gap layer is formed on the exposed substrate and the insulating layer. And a step of forming the upper magnetic layer on the magnetic gap layer, and on the upper magnetic layer,
Forming a first mask layer so that the upper magnetic layer in a predetermined region is exposed in the magnetic yoke tip region having a conversion gap; and selectively etching the material in the exposed region to a predetermined region. A step of forming a shaped magnetic yoke tip, a step of removing the first mask layer, and a step of protecting the magnetic yoke tip and forming a magnetic yoke shape of a portion other than the magnetic yoke tip The step of forming the mask layer, the step of selectively removing the exposed upper magnetic layer, and the step of removing the second mask layer.

The present invention employs a method of forming a magnetic gap layer on an insulating layer to reduce the etching amount of the insulating layer.

Also in the present invention, it is desirable that the magnetic yoke tip region in the step of forming the first mask layer is in front of the conductor coil layer. As a method for selectively removing the upper magnetic layer, an ion beam etching method, a sputter etching method or the like is used when the first mask layer is used, and a chemical etching is used when the second mask layer is used. Is desirable.

Further, in the method of manufacturing a thin film magnetic head of the present invention, after the lower magnetic layer, the magnetic gap layer, the conductor coil layer and the insulating layer are formed on the substrate, at least the magnetic gap exposed on the substrate is formed. A layer, the insulating layer, and the rear gap region, forming an upper magnetic layer, selectively etching the upper magnetic layer to form a magnetic yoke having a predetermined shape, and forming a magnetic yoke in the magnetic yoke tip region. And a step of forming a mask layer so that the upper magnetic layer in a predetermined region is exposed, a step of selectively removing the exposed upper magnetic layer, and a step of removing the mask layer. And

[0016]

According to the method of manufacturing the thin film magnetic head of the present invention, the upper magnetic core is divided into the front end portion which requires precision and the rear portion which includes the portion formed on the insulating layer above the conductor coil layer. For this reason, since the overetching time can be changed between the front end portion and the rear portion, the overetching time in the rear portion, which does not require much accuracy, can be reduced, and the etching amount of the insulating layer on the conductor coil layer can be reduced. Also, since the etching method can be changed between the tip and the back, the tip uses the ion beam etching method, the sputter etching method, or the like, which can obtain the processing accuracy, and the back, the selectivity with the insulating layer can be obtained. By using the easy chemical etching method, it is possible to obtain a thin film magnetic head having a high precision of the tip of the magnetic core and a small etching amount of the insulating layer on the conductor coil layer.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. 3 is a top view of the thin film magnetic head according to the present invention, and FIGS. 1 and 2 are process cross-sectional views showing a manufacturing process as one embodiment of the present invention, showing a cross section taken along the line AA of FIG. ing. First, the NiFe film 12 as the lower magnetic layer is formed on the ceramic substrate 11. Next, an alumina film 13 is formed as a magnetic gap layer, on which a copper film 2 is formed.
Insulating layer 15 so as to wrap the conductor coil layers 14, 14 '
Was formed to obtain the structure shown in FIG. Insulation layer 15
Was manufactured by baking a photoresist at 250 ° C. The thickness of the insulating layer on the second conductor coil layer is 1.5 to 2.5 μm
And On top of this, a NiFe film 1 as an upper magnetic layer
6 (thickness: 3.5 μm) was formed by sputtering, and as shown in FIG.
The structure shown in (b) was obtained. Next, as shown in FIG. 4, on the NiFe film 16 as the upper magnetic layer, a photoresist pattern 17 as the first mask layer is formed so that a part of the NiFe film 16 as the upper magnetic layer is exposed. Was formed to obtain the structure shown in FIG. The region where a part of the NiFe film 16 as the upper magnetic layer is exposed is
This is a magnetic yoke tip region having a conversion gap of the thin film magnetic head, and in this embodiment, a region 5 μm behind the tip of the insulating layer that determines the magnetic gap depth, that is, 10 μm or more forward of the tip of the conductor coil layer 14. And the area. The photoresist pattern 17 was used as a mask to be exposed by an ion beam etching method.
The NiFe film 16 as the upper magnetic layer was etched. The overetching time was 50% of the just etching time. Next, this photoresist pattern 17
Was removed with a stripping solution to obtain the structure shown in FIG.
Next, as shown in FIG. 5, a magnetic mask formed by using the first mask layer 17 protects the tip portion of the magnetic yoke and forms a magnetic yoke shape other than the tip portion as a second mask layer. A photoresist pattern 18 was formed to obtain the structure shown in FIG. The photoresist pattern 18 was used as a mask to be exposed. The NiFe film 16 as the upper magnetic layer was etched by chemical etching using an aqueous ferric chloride solution, and then the photoresist pattern 18 was removed with a stripping solution to fabricate a magnetic yoke. Since the ferric chloride aqueous solution does not etch the insulating layer, the conductor coil is not exposed. Therefore, the insulating layer on the conductor coil layer is
Since the thickness required for insulation between the coil and the upper magnetic layer, that is, 1 μm for a normal thin film magnetic head, is sufficient,
It is possible to reduce the element height.

In the embodiment of the present invention, the region of the upper magnetic layer that will be the tip of the magnetic yoke is processed first, but the rear region including the insulating layer on the conductor coil layer may be processed first. In that case, when processing the rear region, it is desirable to process the tip region into a rough shape.

FIG. 6 is a sectional view of a thin film magnetic head manufactured in another embodiment of the present invention, and shows a section taken along the line AA 'of FIG. An NiFe film 22 as a lower magnetic layer is formed on a ceramic substrate 21, and then an insulating layer 24 is formed on the NiFe film 22 so as to wrap the two conductor coil layers 23 and 23 'made of copper. , An alumina film 25 (0.4 μm) as a magnetic gap layer is formed, and then a NiFe film 26 (3.5 μm) as an upper magnetic layer is formed on the magnetic gap layer 25 by using a sputtering method. did. The insulating layer 24 was produced by baking photoresist at 250 ° C. The processing of the NiFe film 26, which is the upper magnetic layer, is performed as shown in FIG.
The first region of the mask was formed by using the first mask layer having the pattern of FIG. 5 and the rear region was formed by using the second mask layer of the pattern of FIG. In this embodiment, the tip region is a region 5 μm behind the tip of the insulating layer that determines the magnetic gap depth,
That is, the region was set to be 10 μm or more in front of the tip of the conductor coil layer 14. The exposed upper magnetic layer was etched by the ion beam etching method regardless of whether the first mask layer or the second mask layer was used. The overetching time is 50 times the just etching time when the tip region is etched using the first mask layer.
%, And when the rear region is etched using the second mask layer, it is set to 15% of the just etching time.
The insulating film on the conductor coil layer has
When the just etching time is as small as 15%, the etching rate in the ion beam etching of the alumina film 25 is 1/3 of that of the NiFe film, so that the alumina layer serves as a stopper and is not etched.

[0020]

According to the manufacturing method of the present invention, it is possible to realize a thin film magnetic head having a small etching amount of the insulating film on the conductor coil layer around the upper magnetic core and a high processing accuracy of the tip portion, so that the insulating film has a uniform shape. Thus, a thin film magnetic head with a high manufacturing yield can be achieved.

[Brief description of drawings]

FIG. 1 is a sectional view of a first step showing a method of manufacturing a thin film magnetic head as an embodiment of the invention.

FIG. 2 is a sectional view of a second step showing the method of manufacturing the thin film magnetic head as the embodiment of the invention.

FIG. 3 is a plan view of a thin film magnetic head according to the present invention.

FIG. 4 is an explanatory diagram of a photoresist pattern according to an embodiment of the present invention.

FIG. 5 is an explanatory diagram of a photoresist pattern according to the embodiment of the present invention.

FIG. 6 is a sectional view of a thin film magnetic head as an embodiment of the present invention.

[Explanation of symbols]

11, 21 ... Ceramic substrate, 12, 16, 22, 26
... NiFe film, 13,25 ... Alumina film, 14,14
', 23,23' ... Copper coil, 15, 24 ... Insulating layer, 1
7, 18 ... Photoresist.

(72) Inventor Hideki Yamazaki 4026 Kujimachi, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi Ltd.

Claims (7)

[Claims] 1. A lower magnetic layer, a magnetic gap layer, and
A thin-film magnetic head having a yoke structure having a conductor coil layer, an insulating layer that insulates the conductor coil from the upper and lower magnetic layers, and an upper magnetic layer, and has a conversion gap at one end and a rear gap region at the other end. In the manufacturing method, the lower magnetic layer, the magnetic gap layer, the conductor coil layer,
And a step of forming the upper magnetic layer in the magnetic gap layer, the insulating layer, and the rear gap region exposed at least on the substrate after forming the insulating layer; and the conversion on the upper magnetic layer. Forming a first mask layer so that the upper magnetic layer in a predetermined region is exposed in the tip region of the magnetic yoke having a gap for use, and selectively exposing the material in the exposed region to a predetermined shape. A step of forming a magnetic yoke tip portion, a step of removing the first mask layer, and a second step of protecting the magnetic yoke tip portion and forming a magnetic yoke shape of a portion other than the magnetic yoke tip portion. A method of manufacturing a thin film magnetic head, comprising: a step of forming a mask layer; a step of selectively removing the exposed upper magnetic layer; and a step of removing the second mask layer. 2. The method of manufacturing a thin film magnetic head according to claim 1, wherein the magnetic yoke tip region in the step of forming the first mask layer is in front of the conductor coil layer. 3. The method according to claim 1, wherein the step of selectively removing the exposed upper magnetic layer is performed by ion beam etching when using the first mask layer and chemically when using the second mask layer. A method of manufacturing a thin film magnetic head which is etching. 4. A lower magnetic layer, a magnetic gap layer, and
A thin-film magnetic head having a yoke structure having a conductor coil layer, an insulating layer that insulates the conductor coil from the upper and lower magnetic layers, and an upper magnetic layer, and has a conversion gap at one end and a rear gap region at the other end. In the method for manufacturing, the step of forming the magnetic gap layer on the exposed substrate and the insulating layer after forming the lower magnetic layer, the conductor coil layer, and the insulating layer, and the magnetic gap layer. Forming the upper magnetic layer on the first magnetic layer, and forming a first mask on the upper magnetic layer so that the upper magnetic layer in a predetermined region is exposed in the magnetic yoke tip region having the conversion gap. A step of forming a layer, a step of selectively etching the material in the exposed region to form a magnetic yoke tip portion having a predetermined shape, a step of removing the first mask layer, and a step of removing the magnetic yoke. A second mask layer that protects the tip of the magnetic yoke and forms the shape of the magnetic yoke other than the tip of the magnetic yoke; a step of selectively removing the exposed upper magnetic layer; A method of manufacturing a thin-film magnetic head, comprising the step of removing the second mask layer. 5. The method of manufacturing a thin film magnetic head according to claim 4, wherein the magnetic yoke tip region in the step of forming the first mask layer is in front of the conductor coil layer. 6. The method according to claim 4, wherein the step of selectively removing the exposed upper magnetic layer is performed by ion beam etching when using the first mask layer, and chemically when using the second mask layer. A method of manufacturing a thin film magnetic head which is etching. 7. A lower magnetic layer, a magnetic gap layer, and
A thin-film magnetic head having a yoke structure having a conductor coil layer, an insulating layer that insulates the conductor coil from the upper and lower magnetic layers, and an upper magnetic layer, and has a conversion gap at one end and a rear gap region at the other end. In the manufacturing method, the lower magnetic layer, the magnetic gap layer, the conductor coil layer,
And a step of forming the upper magnetic layer in at least the magnetic gap layer exposed on the substrate, the insulating layer, and the rear gap region after forming the insulating layer, and selectively forming the upper magnetic layer. Removing to form a magnetic yoke having a predetermined shape; forming a mask layer in the magnetic yoke tip region so that the upper magnetic layer in a predetermined region is exposed; and exposing the exposed upper magnetic layer. A method of manufacturing a thin-film magnetic head, comprising: a step of selectively removing and a step of removing the mask layer.