JPH10116402A - Production of magnetic head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a production method of thin film magnetic head by including processes to form a frame comprising a photoresist, PMGI, etc., to form an undercut part in the frame, and to form upper and lower magnetic pole layers and a gap layer by using the frame. SOLUTION: A lower magnetic pole layer 4 is formed on a substrate through an adhesion layer 5 comprising a metal film such as Cr by a sputtering method or the like, or if the a GMR head is to be produced, a shielding film 4 is formed instead of the lower magnetic pole layer. Then, a resin 1 which is soluble with a developer of a photoresist is applied thereon, and a photoresist 2 is applied to form a two-layer film. The photoresist 2 is exposed and developed through a silicon dioxide film 3 as a mask. Thereby, after the exposed part of the photoresist is dissolved in a developer, the resin 1 as the lower layer is dissolved in the developer to form an undercut part. Then the obtd. frame is used to form an alloy film 6, gap film 7 and upper magnetic pole 8 by plating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing a thin-film magnetic head for a magnetic disk drive.

[0002]

2. Description of the Related Art A thin-film magnetic head for a magnetic disk drive is formed on a slider held on a disk which rotates at a high speed. The recording head has a pole layer which is a thin film of a ferromagnetic material, and has a lower pole layer and an upper pole layer above and below the gap layer on the air bearing surface. The top and bottom pole layers of the recording head contact at the rear gap. In order to increase the recording density, it is necessary to write a lot of data on the surface of the magnetic disk.
For this purpose, there is a method of increasing the recording density by narrowing the track width. The width of the pole tip in a thin film magnetic head,
A method for providing a head having a track width of 2 μm or less is described in Japanese Patent Application No. 7-12264. In this example, a silicon dioxide layer is used as a plating frame when a magnetic film is formed by a plating method. The magnetic head silicon dioxide layer is left around the magnetic pole tip. Materials including silicon, silicon nitride and carbon besides silicon dioxide are mentioned as materials for forming the notch structure. These materials are inferior to alumina in terms of abrasion resistance, and require an apparatus for forming a frame material as compared with a frame material such as a resist, so that the number of process steps is increased.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to form a frame made of photoresist, PMGI, or the like on a substrate, and to form an undercut on the frame.
An object of the present invention is to provide a method of manufacturing a thin-film magnetic head, which includes a step of forming an upper and lower magnetic pole layer and a gap layer using a frame and a step of removing the frame.

[0004]

Means for Solving the Problems A frame material having an undercut is produced by a combination of irradiation of ultraviolet rays and far ultraviolet rays and development twice on a two-layer film using a photoresist and polydimethylglutarimide, and A gap film is formed between the layers, and a lower pole film is formed in the undercut portion. In the present invention, since a frame material such as silicon dioxide is not used, the wear resistance and the apparatus for forming the frame material are not required. As shown in FIG. 1, a resin 1 soluble in a photoresist developer is applied, and a photoresist 2 is
Is applied to form a two-layer film, and using another mask material 3, the photoresist is exposed and developed as shown in FIG.
When processed by IE (Reactive Ion Etching), the exposed portion of the photoresist is dissolved in the developing solution (d), and then the lower resin 1 starts to be dissolved in the developing solution (e). At this time, the lower layer dissolves at a higher speed than the portion other than the exposed portion of the upper photoresist and the side etching proceeds, so that an undercut is formed as shown in FIG. The lower layer material is polydimethylglutarimide (PMGI). P
The MGI can be peeled off with a photoresist stripper. As a method for producing such an undercut, a dummy material dissolved in a photoresist developer is used as shown in FIG.
It is possible to form a track portion by exposing and developing in advance as described above, applying a photoresist thereon (c), and exposing and developing the photoresist 2 using a mask material 3 by exposure or RIE. The track width of the thin-film magnetic head thus formed is 2 μm or less, and R
By optimizing the IE conditions, a track width of up to 0.5 μm can be formed.

In the present invention, when the pole tip of the recording head of the thin-film magnetic head is formed by frame plating, the frame is made of a developable material including a photoresist having an undercut in order to realize a submicron track width. The space between the photoresist above the undercut is the track width. The plating film is formed on the lower magnetic film 6, the gap film 7, and the upper magnetic film 8 in this order on the base film 4 formed on the adhesion film 5 of FIGS. Using the film, an upper magnetic film is formed from the lower magnetic film by a plating method.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A process for producing a recording head will be described below. FIG. 1 shows a method in which an undercut of PMGI is formed using PMGI / photoresist / silicon dioxide as a frame, and a gap film is formed between the photoresists by a plating method. FIG. 2 shows a polydimethyl glutarimide (P
A photoresist frame is formed using MGI) or the like for the dummy layer 9, and the lower magnetic pole 6, the gap film 7, and the upper magnetic pole 8 are formed by plating at the intervals of the photoresist frame.

In FIG. 1, a lower magnetic pole or a shield film 4 in the case of a GMR head is formed on a substrate or a GMR head via an adhesion layer 5 (metal film such as Cr) by a sputtering method, a vacuum evaporation method, or a plating method. . On this, PMGI having a thickness of 0.1 to 5 μm is applied and
Baking was carried out at a temperature of at least ℃. In order to reduce the frame interval of the photoresist 2, the photoresist can be processed by RIE (reactive ion etching) using a silicon dioxide film or the like as a mask. The thickness of the photoresist 2 is 3 to 10 μm. The width of the photoresist frame is 5 to 20 μm. Since the photoresist dissolution rate is low and the PMGI dissolution rate is high, undercuts are formed in the PMGI layer as shown in FIG. Undercut amount is photoresist and PM
Since it is determined by the difference in the dissolution rate of the GI in the developer,
It is necessary to use a photoresist having a low dissolution rate.
Increase the dissolution rate difference and reduce the undercut amount to 0.3 μm
The above can be considered. Next, NiFe or NiFeCo is formed by plating using a frame as shown in FIG.
An alloy film 6 is formed, and a nonmagnetic conductive film 7 of Cr, Au, Pt or the like is plated thereon as a gap film. Further, an upper magnetic pole film (NiFe or NiFeCo) is formed on the gap film.
Alloy film) by a plating method.

FIG. 2 is a view showing the P which forms the undercut shown in FIG.
This is a method in which a dummy layer 9 is formed instead of the MGI layer 1 and the dummy layer is removed to produce an undercut. The plating material and method are the same as those in FIG. Also in this case, an organic material which can be exposed and developed and has a faster dissolution rate of a developing solution than a photoresist formed on the dummy layer is used as the dummy layer.

When the magnetic pole tip is formed in this manner, the sectional shape of the recording head becomes as shown in FIG. 3, the coil 11 is formed by plating with the lower magnetic pole 4 and the insulating layer 14 interposed therebetween, and the resist 12 Insulation is maintained. An upper magnetic pole 13 is provided on the resist 12, and when the upper magnetic pole 13 is formed on the upper magnetic pole 8 in the magnetic pole end portion (a), it can be formed at an end of the upper magnetic pole 8.

[0010]

According to the present invention, a photoresist or PM on a substrate is provided.
A step of forming a frame made of GI or the like, a step of forming an undercut in the frame, a step of forming upper and lower magnetic pole layers and a gap layer using the frame, and a step of removing the frame, and the areal recording density is 1 Gb / in 2 or more. And a method for manufacturing a thin-film magnetic head used in the magnetic disk drive of the present invention.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of one embodiment of a recording head manufacturing process using a frame having an undercut.

FIG. 2 is an explanatory diagram of a second embodiment.

FIG. 3 is an explanatory diagram of a third embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... PMGI layer, 2 ... photoresist layer, 3 ... oxide layer, 4 ... lower magnetic pole layer, 5 ... adhesion layer, 6 ... plating lower magnetic pole layer, 7 ... gap layer, 8 ... upper magnetic pole layer.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor, Moriaki Fuyama 1-280, Higashi-Koigakubo, Kokubunji-shi, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd. (72) Inventor Nobuo Yoshida 1-280 Higashi-Koigakubo, Kokubunji-shi, Tokyo In-house Hitachi, Ltd.

Claims (4)

[Claims] The method includes the steps of forming a frame on a substrate, forming an undercut in the frame, forming upper and lower pole layers and a gap layer using the frame, and removing the frame. A method for manufacturing a thin film magnetic head. 2. A method of manufacturing a thin-film magnetic head, wherein upper and lower magnetic pole layers including a gap layer are formed by plating using a frame having an undercut formed of a two-layer film of photoresist and PMGI. 3. A lower magnetic film is formed on an undercut portion by plating using a frame having an undercut formed of a two-layer film of a photoresist and a PMGI, and a track width is determined by a frame interval of the photoresist on the PMGI. A method for manufacturing a thin-film magnetic head. 4. A method for manufacturing a thin-film magnetic head, comprising: forming an undercut in a photoresist frame using a dummy layer; and forming upper and lower magnetic pole layers including a gap layer in the frame by plating.