JPH06309616A - Production of resist mask - Google Patents

Abstract

PURPOSE:To provide a production method of a resist mask by which a uniform and thick resist mask, which allows ion milling treatment, can be produced. CONSTITUTION:A org. resin film 6 is adhered to a slider block 8, and then a photoresist 9 is applied on the org. resin film 6 and exposed to produce a mask of the photoresist 9. This photoresist mask 9 is used to each the org. resin film 6 to produce a resist mask 10 for the slider block 8. By adhering the org. resin film 6 to the slider block 8, the surface of the org. resin film 6 is formed as a continuous plane so that the photoresist 9 can be uniformly applied. By etching the org. resin film 6, the resist mask 10 can be produced with uniform thickness. By preliminarily adhering a thick org. resin film 6, a thick resist mask 10 is produced which can cope with, ion beam milling.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a resist mask used for a magnetic head for a fixed disk drive.

[0002]

2. Description of the Related Art Recently, the recording density of a fixed disk drive has been increased, but in order to achieve the higher recording density, the track width is narrowed to increase the track density. The flying height is controlled to a predetermined low value. Then, as an example of a method of processing the track or the flying rail that greatly affects the track width or the flying height, there is a method of machining by using a diamond grindstone. However, with this method, it was difficult to accurately process a track of 10 μm or less with a small variation. In addition, the levitation rail is as shown in Figs. 28 and 29,
In the case of a shaped rail such as a so-called negative pressure slider, it was not easy to machine along the shape and it was difficult to control the grinding depth with high accuracy. In the figure, 1a and 2a are levitation rails (air lubrication surface, ABS (Air
Bearing Surface)), 1b and 2b are the air inflow side of the slider, and 1c and 2c are the air outflow side of the slider.

In order to process the track and the flying rail of the recording head with high accuracy, it is possible to use a combination technique of photolithography (photo-etching method using light) and chemical etching or reactive ion etching. However, chemical etching does not have an appropriate etching solution, and reactive ion etching does not have an appropriate etching gas, so that it is difficult to achieve high-precision processing. To improve this, ion beam milling is used which etches by collision with inert ions such as argon.

However, in this ion beam milling, since the etching rate (etching rate) between the photoresist and the object to be processed (object to be etched) is about 1: 1, the resist coating thickness must be increased. . For example, in order to etch 10 μm, the thickness of photoresist must be 10 μm or more. The thicker the photoresist, the poorer the pattern accuracy.

As a means for improving the problem of deterioration of pattern accuracy due to the above ion beam milling, Japanese Patent Publication No. 57-548.
It is possible to apply the method shown in Japanese Patent Laid-Open No. 52-52. In this method, a metal such as Ti having an etching rate greatly different from that of ferrite is used as a resist mask, and argon is mixed with an active gas such as N ₂ or O ₂ to obtain a large difference in etching rate between the _two . There is. However, according to this method, the etching rate by ion beam milling is reduced to about 1/2 as compared with the case where only argon ions are used, resulting in poor productivity.

When a photoresist is applied by spin coating or roller coating on the surface of a rectangular parallelepiped such as a magnetic head slider or a bar-shaped irregular substrate before slider separation or a workpiece having a step on the surface, as shown in FIG. 30, for example. It was very difficult to apply the photoresist 4 uniformly to a constant thickness because the end portion 5 of the photoresist 4 was raised. In addition, in FIG. 30, 3 indicates a workpiece.

As another method of forming a track having a narrow width, there is a so-called laser-assisted chemical etching method of irradiating a workpiece immersed in a chemical etching solution with a laser beam while operating it.

[0008]

However, in the head track formed by the above-described laser assisted chemical etching method, the chemical etching rate is different for each material in the portion where different materials are joined in the vicinity of the magnetic head gap. Therefore, there is a problem that the track width becomes non-uniform and the head characteristics are seriously affected.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist mask manufacturing method capable of manufacturing a resist mask having a uniform thickness and a large thickness that allows ion beam milling. .

[0010]

In order to achieve the above object, the present invention provides a photoresist mask by attaching a film to an object to be processed, applying a photoresist to the film and exposing the film. Then, the film is then etched using the photoresist mask. In this case, the film may be made of an organic resin and the reactive ion etching method may be used for etching the film. Further, as the object to be processed, a deformed substrate, a substrate having a step on the surface, a deformed substrate having a plurality of aligned substrates, or a substrate having a step on the surface of a plurality of aligned substrates may be applied.

[0011]

With this structure, since the film is attached to the workpiece, the surface of the film becomes a continuous surface, so that the photoresist can be uniformly applied. Furthermore, by attaching a thick film in advance, a thick resist mask can be produced, and ion beam milling can be dealt with.

[0012]

EXAMPLES Examples of the present invention will be described below. First,
A first embodiment using an organic resin film 6 as a film will be described with reference to FIGS. 1 to 7.

Several bar-shaped or rectangular parallelepiped slider blocks 8 used for a magnetic head are set side by side on a wafer-shaped jig 7 (FIG. 2), and an organic resin film 6 (dry film) of acrylic resin or the like is placed thereon. Paste (Fig. 1). The thickness of the organic resin film 6 is set by the depth of ion beam milling. For example, when etching a depth of 10 μm, the thickness of the organic resin film 6 is 15 μm.
Set to m.

Photoresist 9 on organic resin film 6
Is spin coated (FIG. 3). Since the slider block 8 is set on the wafer-shaped jig 7 and the organic resin film 6 is attached thereon, the surface of the organic resin film 6 is a continuous surface. Therefore, the photoresist 9 can be applied uniformly.

The photoresist 9 is exposed and developed (FIG. 4). Since the thickness of the photoresist 9 is thin, a good fine line pattern can be formed (2 μm or less is also possible).
As described above, in a generally known photoresist coating method such as spin coating on the upper surface of a rod-shaped or rectangular parallelepiped object, the photoresist is uniformly coated, and a thick pattern is formed on a thick photoresist. Although it is difficult to expose the
As described above, uniform coating of the photoresist 9 and formation of a fine line pattern can be achieved.

Using the pattern of the photoresist 9 as a mask, a gas having a 1: 1 mixture of O ₂ and He, for example, is used at a pressure of 0.01 Torr and an RF (Radio Friquency) power of 200.
The organic resin film 6 is etched by reactive ion etching using oxygen gas with W (FIG. 5). As a result, a resist mask 10 for ion beam milling having the same width as the pattern of the photoresist 9 and the same height as the organic resin film 6 is produced. By the above method, the thin line pattern (2 μm or less) which is thick and uniform with respect to the workpiece to which the photoresist 9 cannot be uniformly and thickly applied in the conventional technique, for example, the slider block 8 of the magnetic head, can be applied accurately. Can also be formed).

Using the resist mask 10 manufactured as described above, the slider block 8 is etched by ion beam milling containing an inert gas (FIG. 6). At this time, it is desirable to use argon gas having a high etching rate as the inert gas. Then, the resist mask 10 is peeled off (FIG. 7). Since the resist mask 10 is the organic resin film 6, it can be easily peeled off with an organic solvent or the like.

Next, a second embodiment of the present invention will be described with reference to FIGS. This second embodiment is intended for track processing of a monolithic type magnetic head using Mn-Zn ferrite for the slider material and the core material.

First, as shown in FIGS. 8 to 10, a slider block 8 (bond bar) including a U-shaped bar 11 and an I-shaped bar 12 made of ferrite and having a magnetic gap 13 is manufactured. A soft magnetic metal such as sendust is applied to the surface facing the gap. The surface on which the magnetic gap 13 is formed is processed and polished so as to have a predetermined magnetic gap depth (depth) (FIG. 10). A plurality of slider blocks 8 are arranged on a jig 7 having a predetermined shape (FIGS. 11 and 12).

An organic resin film 6 such as an acrylic dry film is attached (FIG. 13). In this case, when the etching depth is 10 μm, the organic resin film 6 having a thickness of 15 μm is attached. This attachment can be performed by passing the organic resin film 6 and the jig 7 through two heated rolls. As shown in FIG. 14, the slider block 8
May be cut to form one magnetic head slider 14, which is then arranged on the jig 7 and the organic resin film 6 may be attached.

A photoresist 9 is applied by spin coating to the surface to which the organic resin film 6 is attached (see FIG. 1).
Five). Since the upper surface of the jig 7 on which the slider blocks 8 are arranged is continuous by sticking the organic resin film 6, the photoresist 9 can be applied by spin coating. In this case, as the photoresist 9, it is preferable to use a silylated photoresist (resist in which Si is contained in the polymer of the photoresist) which is difficult to be etched by reactive ion etching using oxygen gas. The thickness of 2 μm or less is sufficient. The applied photoresist 9 is subjected to a process using an optical photography technique to form a pattern of the photoresist 9 having a shape along the track 15 (FIGS. 16, 17, and 18).

The organic resin film 6 is etched by reactive ion etching using a mixed gas of O ₂ and He with the pattern of the photoresist 9 produced in the steps shown in FIGS. 16, 17 and 18 as a mask. A pattern of the resist mask 10 used for milling is formed (FIG. 19). The mixed gas at this time contains O ₂ as a main component, and one kind or a combination of gases such as He, Ar, Xe and N ₂ may be added to stabilize the plasma. Further, a reactive gas such as Cl ₂ , CF ₄ , CHF ₃ or the like may be added to enhance the etching effect. The etching conditions at this time are low gas pressure,
It is desirable that the organic resin film 6 has a high input power and the etching shape of the organic resin film 6 is vertical so that there is no undercut.

Ion beam milling is performed by using the pattern 10 of the organic resin film 6 produced in the above process as a mask and using an inert gas such as Ar, Kr or Xe (FIG. 20). In this case, N ₂ or the like may be used. However, M
As for n-Zn ferrite, when Ar gas is used, the etching rate becomes the fastest, so it is preferable to use Ar gas. Further, the total ion power density is preferably up to about 3 W / cm ² when the temperature rise of the sample is taken into consideration. For example, when the organic resin film 6 having a thickness of 15 μm is used, the depth of ferrite removed can be up to about 10 μm.

The organic resin film 6 used as the resist mask 10 is peeled off. The peeling of the organic resin film 6 can be achieved by using an organic solvent or an O ₂ asher. The slider block 8 that has been etched by the ion beam milling of the track 15 is cut and processed to produce the magnetic head slider 14 having a predetermined shape (FIG. 2).
1).

The track processing of the monolithic head has been described above. The composite type magnetic head 16
(Figs. 22 and 23), laminated type magnetic head 17 (Figs. 24,
25) or the thin film magnetic head 18 (FIGS. 26 and 27) can be track-processed by ion beam milling through similar steps. 22 to 27, 13 is a magnetic gap, 19 is a ceramic slider, 20 is a ferrite core, 21 is an etched portion, 22 is an upper magnetic pole, 23 is a lower magnetic pole, and 24 is a track width.

Next, a description will be given of a third embodiment targeting the processing of the floating rail (ABS). This third embodiment is the second
Compared with the embodiment, for example, when the etching depth is 30 μm, an organic resin film 6 having a thickness of about 50 μm is attached, and other steps are the same as those in the second embodiment. I'm trying to do the same. Also in this third embodiment, since the organic resin film 6 is attached to the slider block 8, the surface of the organic resin film 6 becomes a continuous surface, and the photoresist 9 can be uniformly applied. The resist mask 10 can be manufactured.

In order to increase the linear recording density, it is required to lower the flying height of the slider as described above, and at present, the flying height is lowered to about 0.1 μm. Further, in order to reduce the flying height and control the flying height to a constant level, application to a shaped rail such as a negative pressure slider as shown in FIGS. 28 and 29 can be considered. These shapes cannot be formed by grinding or the like. In addition, the rail depth must be accurately formed in order to accurately control the low flying height. This is also difficult with grinding. Therefore, as described above, ABS processing such as ion beam milling has been proposed. However, it is difficult to form a thick and accurate photoresist pattern on the rod-shaped slider block 8 described above. Moreover, the ABS processing requires an etching depth of up to about 50 μm. At this time, the thickness of the resist required is 50 μm or more, and it becomes very difficult to apply and pattern with high precision.

On the other hand, in the third embodiment, since the organic resin film 6 is attached to the slider block 8 as described above, the surface of the organic resin film 6 becomes a continuous surface and the photoresist 9 is evenly formed. Since the resist mask 10 that can be applied and has a uniform thickness can be produced by the etching process, the working of the levitation rail can be achieved with high accuracy, and the problems of the above-mentioned conventional technique can be improved.

[0029]

EFFECTS OF THE INVENTION The present invention is a method for producing a resist mask having the above-described structure. Therefore, a film is attached to a work piece so that the film surface becomes a continuous surface and the photoresist can be uniformly applied. Therefore, a resist mask having a uniform thickness can be produced by etching the film. Furthermore, by pasting a thick film in advance, a thick resist mask is created,
It will be possible to deal with ion beam milling. When the film is made of an organic resin, subsequent peeling of the organic resin film can be easily achieved with a commonly used organic solvent. By applying a deformed substrate, one having a step on the surface, one having a plurality of aligned irregular substrates, or one having a plurality of aligned surfaces on the surface as the workpiece, the conventional photoresist coating method A uniform coating of photoresist can be achieved on these unworkable workpieces.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a state where a film is attached according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a set state of the slider block of the first embodiment.

FIG. 3 is a cross-sectional view showing a state in which a photoresist is spin-coated on an organic resin film.

FIG. 4 is a cross-sectional view showing a state where a photoresist is exposed.

FIG. 5 is a cross-sectional view showing a state in which an organic resin film is etched.

FIG. 6 is a cross-sectional view showing a state where a slider block is etched by ion beam milling.

FIG. 7 is a cross-sectional view showing a state in which a resist mask is peeled off.

FIG. 8 is a perspective view showing a U-shaped bar according to a second embodiment of the present invention.

FIG. 9 is a perspective view showing an I-shaped bar in the second embodiment.

FIG. 10 is a perspective view showing a slider block according to the second embodiment.

FIG. 11 is a cross-sectional view showing a set state of the slider block.

FIG. 12 is a plan view showing a set state of the slider block.

FIG. 13 is a cross-sectional view showing a pasted state of an organic resin film.

FIG. 14 is a plan view showing a cut state of a slider block.

FIG. 15 is a cross-sectional view showing a state in which a photoresist is applied to an organic resin film.

FIG. 16 is a cross-sectional view showing a state where a photoresist pattern having a shape along a track is formed.

FIG. 17 is a perspective view of a slider block schematically showing the photoresist pattern formation state.

18 is a partially enlarged plan view of FIG.

FIG. 19 is a cross-sectional view showing a state where a resist mask pattern used for ion beam milling is formed.

FIG. 20 is a cross-sectional view showing a state of performing ion beam milling.

FIG. 21 is a plan view showing a monolithic type magnetic head obtained by cutting a slider block.

FIG. 22 is a plan view showing a composite type magnetic head.

FIG. 23 is a partially enlarged view of FIG. 22.

FIG. 24 is a plan view showing a laminated type magnetic head.

25 is a partially enlarged view of FIG. 24.

FIG. 26 is a plan view showing a thin film magnetic head.

27 is a partially enlarged view of FIG. 26.

FIG. 28 is a perspective view showing a negative pressure slider.

FIG. 29 is a perspective view showing a negative pressure slider.

FIG. 30 is a front view schematically showing an edge rising state that occurs when photoresist is applied by spin coating or roller coating.

[Explanation of symbols]

 6 Organic resin film 8 Slider block 9 Photoresist 10 Resist mask

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Nobuaki Miuchi 1743-1, Asana-cho, Iwata-gun, Shizuoka Prefecture Minebea Co., Ltd. Development Technology Center (72) Inventor Mitsuru Tomita 1743 Asana-cho, Iwata-gun, Shizuoka Prefecture -1 Minebea Co., Ltd. Development Technology Center

Claims (3)

[Claims] 1. A photoresist mask is produced by pasting a film on a workpiece, applying a photoresist to the film, and exposing the film, and then etching the film using the photoresist mask. A method of manufacturing a resist mask, comprising: 2. The method for producing a resist mask according to claim 1, wherein the film is made of an organic resin, and a reactive ion etching method is used for etching the film. 3. The resist mask according to claim 1, wherein the object to be processed is a deformed substrate, a substrate having a step on the surface, a deformed substrate composed of a plurality of aligned substrates, or a step having a surface composed of a plurality of aligned substrates. Manufacturing method.