JP2863018B2 - Fine processing method by dry etching and resist mask resin composition for dry etching - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to a high-precision dry etching of hard-to-work material, in particular, precision microfabrication of a magnetic head used in a magnetic storage device, preferably for example a track width processing, the head slider rail machining Dry
Fine processing method by etching and dry used for it
The present invention relates to an etching resist mask resin composition .

[0002]

2. Description of the Related Art As is well known, fine processing by dry etching is used in various fields requiring high-precision processing. Hereinafter, an example of a magnetic desk device among magnetic storage devices will be described as a representative example. In recent years, with the increase in the amount of information, higher recording densities have been required in magnetic disk devices. With this, magnetic heads that perform recording on a recording medium (magnetic disk) and reproduction from the recording medium have
Thin-film magnetic heads are being used, and the slider of this magnetic head is required to reduce the flying height, and the distance between the flying slider and the rotating magnetic disk surface has become extremely narrow, and the slider processing has become finer and more precise. Is urgently needed.

Conventionally, thin-film magnetic head sliders have been processed by machining, but from the viewpoint of miniaturization and shapes including curved surfaces, the processing accuracy is no longer limited, and the development of a new processing method is desired. I was In order to solve these problems, a method of forming a precise pattern of a head slider by dry etching has been proposed. This method is superior to mechanical processing in that it can be processed with high precision and without distortion. However, since a thin metal pattern is used as a mask for dry etching, processing of difficult-to-process materials such as magnetic materials is usually performed. Resistance to argon ion etching generally used in
It has been difficult to obtain a processing accuracy sufficient to achieve a flying height of μm or less. As for the dry etching of this type, see, for example, Japanese Patent Application Laid-Open No. 62-124684.
Publication No.

Recently, for example, vacuum, 1
988, Vol. 38, No. 11, page 1007 [V
acumum Vol. 38, Number 11, Pag
es1007-1009 (1988)] and U.S. Pat. No. 4,878,290,
The use of an organic polymer material that is resistant to argon ion etching as a mask material has been studied. However, in this case as well, the incident angle dependence on the sputtering yield of argon ions is large, and therefore the resist mask is inevitably thick and the processing accuracy is low. Recently, hydrocarbon mask materials having an aromatic group (benzene nucleus) in a molecule, such as polystyrene and phenol novolak, have been generally used as these resist masks. However, the argon ion etching resistance of these resist masks is still insufficient, and when the processing depth when processing a slider or the like is large, it is necessary to considerably thicken the mask resist according to the processing depth,
As described above, the processing accuracy is not high.

On the other hand, there is an example in which a carbon film is used as a mask as a mask material having excellent argon ion resistance.
The dense carbon film has a smaller sputtering yield for argon ions than other mask materials, and can be an excellent etching mask material. However, usually, when a dense carbon film is formed, the deposition rate of the carbon film is 1 μm per hour even if the film is formed at a high speed by a stationary facing sputtering apparatus.
m, which is very slow, for example, when the processing depth is as large as 20 μm as in the thin film magnetic head slider processing, there is a problem that it takes several tens of hours to form a carbon film. In addition, since the film formation method is performed in a vacuum, throughput becomes a problem, and this becomes a bottleneck in reducing manufacturing costs. Furthermore, since it is impossible to impart photosensitivity to a carbon film, patterning by lithography is difficult, and there is a problem that there is no possibility of streamlining the process in the future. Japanese Patent Application Laid-Open No. 63-168810, for example, relates to this type of carbon mask.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned drawbacks of the prior art. A first object of the present invention is to provide a resist mask resin composition for dry etching having excellent dry etching resistance . The second object is to provide a fine processing method by dry etching using the mask.

[0007]

In dry etching, the present inventors have focused on carbon as an element having the smallest sputtering yield of argon ions, and have employed a high-precision, low-cost dry etching process utilizing this. Experiments and studies have been advanced. As a result, in a dry etching resist mask material having a benzene nucleus such as benzene, naphthalene or anthracene in the molecule (main chain and / or side chain), that is, a matrix polymer having an aromatic group as a main component, By dispersing and mixing a carbon-based filler, it has been found that argon ion resistance can be significantly improved. That is, it has been found that the selectivity of the mask to the material to be etched during dry etching can be significantly improved by dispersing and mixing a predetermined amount of the carbon-based filler in the matrix polymer.

The present invention has been made based on such knowledge, and means for solving the above-mentioned problems will be specifically described below in order. The dry etching method using argon ions is used, for example, in high-accuracy dry-etching of difficult-to-process materials such as rail processing of a magnetic head slider and magnetic head track width processing. In this case, the difficult-to-work material refers to, for example, alumina titanium carbide, titanium oxide, zirconium oxide, permalloy, or the like. When processing these materials, a mask material is usually patterned on these substrates by lithography, and rare gas ions typified by argon ions or chemically etched such as carbon tetrafluoride. The substrate is dry-etched by adding a promoting gas. At this time, if the etching resistance of the mask material is small,
Since the selectivity of the etching mask material to the difficult-to-process material is small, it is necessary to increase the thickness of the mask material in advance in consideration of the degree of etching of the mask surface.
However, when the thickness of the mask material is large, there is a problem that dimensional accuracy during processing is reduced. Usually, in order to enhance etching resistance, a polymer having many aromatic groups in a molecule is used as a mask material.

However, in these materials, when the incident angle of argon ions to the material to be etched deviates from the vertical direction, the dependency of the dry etching resistance on the incident angle increases, and the selectivity to the material to be etched is greatly reduced.
The angle of incidence of the argon ion beam greatly affects the selectivity between the material to be etched and the mask material, the etching rate, and the re-adhesion phenomenon during etching. For example, at normal incidence, there is a problem such as redeposition during etching, and it is necessary to optimize the incidence angle. Normally, it is preferable to use the resist within a range of 15 to 60 degrees from the perpendicular to the substrate. However, with a resist having a large incident angle dependence, the etching resistance is reduced, and a margin for this optimization cannot be obtained. In order to increase the margin at the time of etching, it is necessary to use a material having a small incident angle dependence as a mask. Furthermore, since the pattern cross section of the mask material is not perpendicular but always has a taper angle, even if the argon ion beam is vertically incident, the taper angle changes during etching, and the incident angle dependence is reduced. Become big.

Therefore, in the present invention, in order to process a difficult-to-process material at low cost and with high selectivity with little dependence on the incident angle, the sputtering yield of argon ions in the resist mask material is reduced. Small carbon powder is dispersed and contained.

That is, a first object of the present invention is to provide a matrix polymer having an aromatic group in a molecule (main chain or side chain) formed as a mask on a substrate to be a predetermined material to be etched, and a resist mask resin composition mainly composed of a solvent dissolving, dispersing the carbon-based filler in the matrix polymer, by a dry etching resist mask resin composition comprising the additional inclusion,
Achieved. The effect of improving the dry etching resistance varies depending on the combination of materials, but at least the etching rate ratio of the material to be etched with respect to the resist mask for dry etching can be 0.8 or more.

The resist mask containing the carbon filler is formed by preparing a resin composition which achieves the first object and applying the resin composition on a substrate or forming a film by using the resin composition. What is necessary is just to laminate on a board | substrate.

The solvent used for preparing the resin composition varies depending on the type of the matrix polymer, but basically any solvent that can dissolve the resin component may be used. It is necessary to optimize in consideration of the dispersibility of the system filler, the film forming property at the time of coating, and the like. Generally, ester solvents such as ethyl cellosolve acetate, methyl cellosolve acetate, propylene glycol acetate, and ethyl cyclohexanone lactate are preferred.
In order to uniformly disperse the carbon-based filler in the resin composition without agglomeration, it is desirable to add a dispersant such as a polyethylene glycol-based surfactant.

The carbon filler may be amorphous or crystalline as long as it is a carbon fine powder having good dispersibility in a resin solution in which a matrix polymer is dissolved. The particle size of the carbon fine powder to be added is preferably as small as possible in consideration of dispersibility. Practically preferable examples include carbon black having an average particle diameter of 0.1 μm or less, and fine diamond powder having an average particle diameter of 0.15 μm or less.

The amount of the carbon-based filler to be dispersed and mixed is preferably at least 5% by weight based on the matrix polymer, and the upper limit depends on the type of the resin, but is preferably dispersed in the matrix polymer resin solution. It is effective to the extent that it can be obtained and the range that can be formed as a mask,
Practically, it is up to about 200%. Regarding the lower limit, even if it is added in a small amount, a certain effect is recognized, but 5
%, The improvement of the resistance of the mask to dry etching is not sufficient.

Therefore, the preferred amount of dispersion and mixing is 5 to 2
00%, and more preferably 50 to 100%.
When the concentration is increased, the resistance of the mask to dry etching is improved. However, when the concentration exceeds the limit, the dispersibility in the resin composition becomes poor, and it becomes difficult to apply the mask uniformly on the material to be etched. Therefore, it is important to determine the preferable dispersion and mixing amount of the carbon-based filler in consideration of the effect of improving the etching resistance of the mask and the dispersibility in the resin composition and the film-forming property as a mask. .

The matrix polymer in the above resin composition will be described in detail. Aromatic polyamic acid, aromatic polyimide, phenol novolak, cresol novolak, pyrogallol-based resin, styrene polymer such as polyhydroxystyrene, etc. Are possible.

The above resin composition can be imparted with photosensitivity as required. For example, when used as an alkali-soluble positive resist, as the matrix polymer, use a phenol novolak resin or the like having an alkali-soluble phenolic hydroxyl group, and by adding a photosensitive dissolution inhibitor thereto, the resin composition becomes It becomes an alkali developing type positive resist. However, in this case, it is necessary to consider the light transmittance of the carbon-based filler to be dispersed. That is, in the case of a resin composition containing a photosensitive dissolution inhibitor having sensitivity to g-line and i-line, it is not preferable to use a material having a low ultraviolet transmittance such as carbon black. In such a case, fine powder having a diamond structure having a high transmittance in the ultraviolet region may be used as the carbon-based filler.

As the photosensitive dissolution inhibitor at this time, for example, 1,2-naphthoquinonediazides are effective.
Examples of the 1,2-naphthoquinonediazides include, for example, naphthoquinonediazide esters of trihydroxybenzophenone and tetrahydroxybenzophenone.

As a method for applying the above-mentioned resin composition to the material to be etched, spinner coating, spraying, dipping, roll coater printing, screen printing, and the like can be used. In addition to the application, a film may be formed from this resin composition, and this may be laminated on the surface of the material to be etched. Furthermore, when the resin composition is provided with photosensitivity when forming the resist mask, a mask pattern can be formed by directly exposing and developing the mask film by ordinary lithography. In the case where the photosensitivity is not provided, the number of steps increases, but in order to pattern a resist mask material containing a carbon-based filler, a known photoresist is formed thereon and selectively etched using the photoresist as a mask. If desired, a desired resist mask pattern for dry etching can be formed. That is, in this case, a two-layer resist mask is formed.

Further, a second object of the present invention is to form a resist mask pattern of a predetermined shape on a predetermined substrate to be etched, and to finely process the substrate by dry etching. This is achieved by a microfabrication method using dry etching, comprising a step of dry-etching the substrate to be etched by physical etching using argon gas ions, which is made of the resist mask resin composition described above. At the time of etching, it is preferable to perform dry etching under the condition that the etching rate ratio of the substrate to be etched to the resist mask is 0.8 or more in consideration of the selection of the material of the substrate to be etched and the resist mask.

As a specific example of the fine processing method, for example, the substrate to be etched is a magnetic head slider, the resist mask pattern is formed at a position corresponding to a slider sliding surface, and the substrate is selectively etched by dry etching. If the slider rail is formed by etching, the magnetic head slider can be finely processed with excellent accuracy. Further, the substrate to be etched is a magnetic head substrate having a magnetic metal film formed on its surface, the resist mask pattern is formed at a position corresponding to the track width of the magnetic head, and the magnetic metal film is selected by dry etching. If etching is performed, the track width of the magnetic head can be finely processed with excellent accuracy. In the dry etching, fine processing can be performed by physical etching using not only argon ions but also rare gas ions such as xenon and krypton. However, in the case of this resist mask, argon ions and xenon ions are particularly preferable among the rare gas ions.

Further, the fine processing by dry etching of the present invention is mainly performed by physical etching using argon gas ions, but depending on the type of the material to be etched, as described above, for example, chemically processing such as carbon tetrafluoride. A reactive gas that promotes etching can also be introduced as a secondary component to accelerate the processing speed.

[0024]

The resist mask tree for dry etching of the present invention
Since the fat composition contains a carbon-based filler in a matrix polymer having an aromatic group in the molecule, these compositions significantly increase the resistance of the mask to physical etching by argon gas ions during dry etching. Has the effect of improving. Therefore, it can be a mask having a large etching selectivity with respect to the material to be etched.

[0025]

In the following, Examples 1 to 5 are examples in which the present invention is applied to rail processing constituting a sliding portion of a thin film magnetic head slider, and Example 6 is applied to track width processing of a magnetic head. An example of each case will be shown and specifically described. <Example 1> Fig. 1 shows a processing step diagram, which will be described according to the drawing. In FIG. 1A, reference numeral 1 denotes a slider substrate serving as a material to be etched, using alumina titanium carbide. On this substrate, a non-photosensitive resin composition having the following composition was prepared as a resist mask resin composition 2 for dry etching as shown in FIG.

[Preparation of Resin Composition 2] 30% by weight of carbon black as a carbon-based filler, 30% by weight of polyhydroxystyrene (using Marcalezin-M manufactured by Maruzen Petroleum) as a matrix polymer,
9% by weight of a polyethylene glycol-based dispersant as a dispersant and 31% by weight of propylene glycol methyl acetate as a solvent were weighed, mixed and stirred to obtain a resin composition.

The coating was performed by a spin coating method, and a film having a thickness of about 35 μm was formed at a rotation speed of 1500 rpm for 60 seconds. This was baked at 150 ° C. for 30 minutes to obtain a dry etching mask material. As shown in FIG. 3C, a positive silicon-based resist (RU1600P (trade name, manufactured by Hitachi Chemical Co., Ltd.) is formed as the photoresist 3 to a thickness of 2 μm by a spin coating method.
After pre-baking for 30 minutes, exposure and development were performed through a mask on which a predetermined rail processing pattern was drawn as shown in FIG. Exposure is performed using ultraviolet light having a wavelength of 365 nm and an irradiation amount of 80.
The development was performed under the condition of mJ / cm ² , and development was performed using an organic amine-based dedicated developer AH112 (trade name, manufactured by Hitachi Chemical Co., Ltd.).

After the patterned photoresist 4 was formed, the dry etching resist mask material 5 was patterned by oxygen reactive ion etching as shown in FIG. Using this dry etching resist mask 5 as a mask, the head slider substrate 1 was processed by a dry etching method using argon ion etching as shown in FIG. The dry etching conditions at this time were: acceleration voltage 700 V, deceleration voltage 200 V, arc voltage 80 V, Ar flow rate 15 m / min.
1, the ion incidence angle was 60 degrees. The processing depth was about 20 μm, and the processing accuracy of the rail width at this time was ± 3 μm in terms of transfer accuracy, and a good result was obtained. Although the thickness of the mask 5 was reduced as shown by 5 ', the mask 5 could sufficiently function as a mask.

The relationship between the etching rate of the resist mask 5 for dry etching used at this time during argon ion etching and the dependence of the argon ion beam on the incident angle was measured. The result shown in FIG. 3 was obtained. .
FIG. 3 also shows, as comparative examples, examples of a resist mask in which carbon black is not dispersed, and examples of alumina titanium carbide and sputtered carbon. As is clear from this figure, the angle of incidence of argon ions is zero.
The etching rate of the resist mask 5 used in this embodiment has characteristics equal to or higher than that of alumina titanium carbide even when the temperature changes from 80 degrees to 80 degrees, and has a large incident angle margin as a resist mask for dry etching. It turns out that it shows.

Second Embodiment FIG. 2 shows a processing step diagram of another embodiment, which will be described below. In FIG. 1A, reference numeral 1 denotes a material to be etched serving as a slider substrate, and a zirconium oxide substrate was used. On this substrate, as shown in FIG. 4B, a coating film made of an orthodiazonaphthoquinone-based positive photosensitive resin composition was formed as a resin composition 2 for a dry etching mask. The following resin composition was prepared and used as a coating solution for forming a coating film.

[Preparation of Resin Composition 2] 25% by weight of an alkali-soluble pyrogallol resin (trade name: XPS-4005B "manufactured by Gun Ei Chemical Co., Ltd.) as a matrix polymer, and naphtho of trihydroxybenzophenone as a dissolution inhibiting photosensitizer Quinonediazide ester 6
% By weight, 30% by weight of diamond fine powder having an average particle diameter of 0.08 μm as a carbon-based filler, 9% by weight of a polyethylene glycol-based dispersant as a dispersant, and 30% by weight of ethyl cellosolve acetate as a solvent were weighed, mixed, and stirred. Then, it was prepared as a photosensitive resin composition.

This photosensitive resin composition was applied on the substrate. The coating was performed by a spin coating method, and a film of about 30 μm was formed at a rotation speed of 1500 rpm for 60 seconds. This was pre-baked at 90 ° C. for 30 minutes to obtain a resist mask material 2 for dry etching. This is exposed to light of 6000 mJ / cm ² using 365 nm ultraviolet light through a mask on which a predetermined rail processing pattern is drawn using a contact aligner as shown in FIG. Development was performed using a 2.38% aqueous solution of tetramethylammonium hydroxide (trade name: NMD-3 manufactured by Tokyo Ohka Kogyo Co., Ltd.).

After the patterned resist mask 5 for dry etching is formed, the resist mask 5 is processed by an argon ion etching method as shown in FIG.
The slider rail part 6 was formed. The dry etching conditions at this time were as follows: acceleration voltage 700 V, deceleration voltage 20
The test was performed under the conditions of 0 V, an arc voltage of 80 V, an Ar flow rate of 15 ml per minute, and an ion incidence angle of 0 degree. Processing depth is about 15μm
At this time, the processing accuracy of the slider rail width was ± 3.6 μm in transfer accuracy, and a good result was obtained. Although the thickness of the mask 5 was reduced as shown by 5 ', the mask 5 could sufficiently function as a mask. At this time, the etching rate of the resist mask 5 is 1.1 to 0.8 times the zirconium oxide substrate 1, which is the material to be etched, in the range of the incident angle of the argon ion beam from 10 degrees to 170 degrees. It has been found that it has excellent characteristics as a resist mask for dry etching.

Third Embodiment An example in which a material to be etched is dry-etched by substantially the same procedure as the processing step shown in FIG. 2 of the second embodiment will be described below. A titanium oxide substrate was used in place of the zirconium oxide substrate 1 of Example 2 shown in FIG.
A coating film 2 was formed by using a photosensitive bisazide-based negative resin composition as a resin composition for a dry etching mask in the same procedure as in (b). The formation of this coating film was carried out by using 22% by weight of poly (4-hydroxystyrene) as a composition and 4-methyl-2,6-di (4 ′) as a bisazide-based photosensitive agent.
-Azidobenzylidene) -cyclohexane-1-one 4
4% by weight, fine diamond powder 4 having an average particle size of 0.08 μm
0% by weight, polyethylene glycol-based dispersant 8% by weight,
A photosensitive resin composition comprising 26% by weight of ethyl cellosolve acetate as a solvent was prepared, and a predetermined amount thereof was applied to the substrate 1
Transfer was performed by spin-coating.

The coating was performed by a spin coating method, and a film having a thickness of about 35 μm was formed at a rotational speed of 1500 rpm for 60 seconds. This was prebaked at 90 ° C. for 30 minutes to obtain a dry etching mask material 2. This is shown in FIG.
Using a contact aligner in the same procedure as described above, a wavelength of 365 n
exposure to light with an irradiation amount of 3500 mJ / cm ² using an ultraviolet ray of m and a 2.38% aqueous solution of tetramethylammonium hydroxide (trade name NMD-3 manufactured by Tokyo Ohka Kogyo Co., Ltd.) as a developing solution.
Was used for the development. After forming the patterned resist mask 5 for dry etching,
The slider rail 6 was formed by processing using an argon ion etching method in the same procedure as in FIG.

The dry etching conditions at this time were as follows:
Acceleration voltage 700V, deceleration voltage 200V, arc voltage 80
V and Ar flow rates were 15 ml per minute and the ion incidence angle was 40 degrees. The processing depth was about 15 μm, and the processing accuracy of the slider rail width at this time was ± 3.8 μm in terms of transfer accuracy, and a good result was obtained. At this time, the etching rate of the resist mask 5 is 0.9 to 0.7 times that of the titanium oxide substrate 1, which is the material to be etched, in the range of the incident angle of the argon ion beam from 10 degrees to 170 degrees. It was found that it had excellent characteristics as a mask material for dry etching.

Fourth Embodiment An example in which a material to be etched is dry-etched by substantially the same procedure as the processing step shown in FIG. 1 of the first embodiment will be described below. An alumina titanium carbide substrate was used as the material 1 to be etched shown in FIG.
On this substrate, a resist mask material 2 for dry etching was formed in the same procedure as in FIG.
30μ in which 35% by weight of carbon black is dispersed
m, and this was laminated on a substrate to obtain a resist mask material for dry etching. A positive silicon-based resist (RU1600P (trade name, manufactured by Hitachi Chemical Co., Ltd.)) is applied as a photoresist 3 on the resist mask material 2 in the same procedure as in FIG.
After prebaking at 90 ° C. for 30 minutes, exposure and development were performed through a mask on which a predetermined rail processing pattern was drawn in the same procedure as in FIG.

Exposure was carried out with ultraviolet light having a wavelength of 365 nm and an irradiation amount of 80 mJ / cm ² , and development was carried out using an organic amine-based dedicated developer AH112 (trade name, manufactured by Hitachi Chemical Co., Ltd.). After the patterned photoresist 4 was formed, the resist mask material 5 for dry etching was patterned by a reactive ion etching method using oxygen in the same procedure as in FIG. Using this dry etching resist mask 5 as a mask, the head slider substrate 1 was processed by a dry etching method using argon ion etching as shown in FIG.

The dry etching conditions at this time were as follows:
Acceleration voltage 700V, deceleration voltage 200V, arc voltage 80
V and Ar flow rates were 15 ml per minute and the ion incidence angle was 60 degrees. The processing depth was about 20 μm, and the processing accuracy of the slider rail width at this time was ± 3.4 μm in terms of transfer accuracy, and a good result was obtained. Also, as a result of measuring the relationship between the etching rate and the argon ion beam incident angle dependence of the dry etching resist mask 5 used in this case at the time of argon ion etching, even if the incident angle changes from 0 ° to 80 °, the present invention is not changed. The etching rate of the resist mask used in the example is equal to or higher than that of the alumina titanium carbide substrate, and it can be seen that the resist mask has a large incident angle margin and excellent characteristics.

Comparative Example 1 A comparative example of rail processing of a slider substrate by dry etching in the same processing procedure as that shown in FIG. 2 of Example 2 will be described. As the slider substrate serving as the material 1 to be etched in FIG. 2A, alumina titanium carbide was used instead of zirconium oxide. On top of this, FIG.
Resin composition for dry etching mask 2 in the same procedure as
After pre-baking at 90 ° C. for 30 minutes using a positive photoresist (not including a carbon-based filler) manufactured by Company A, which has been conventionally generally used as an organic mask material, FIG. Exposure and development were performed in the same procedure.

This is exposed to light of 6000 mJ / cm ² using a contact aligner and a mask having a predetermined rail processing pattern in the same procedure as in FIG. The development was carried out using a commercially available 2.38% aqueous solution of tetramethylammonium hydroxide as a developing solution. After the resist mask 5 for dry etching patterned in this manner was formed, it was processed using the argon ion etching method in the same procedure as in FIG.

The dry etching conditions at this time were as follows:
Acceleration voltage 700V, deceleration voltage 200V, arc voltage 80
V and Ar flow rates were 15 ml per minute and the ion incidence angle was 60 degrees. The processing depth was about 20 μm, and the processing precision of the slider rail width at this time was ± 5.5 μm in transfer precision, and it was found that the processing precision was inferior to the results shown in any of the above examples.

FIG. 3 shows, as a comparative example, the result of measuring the relationship between the etching rate and the argon ion beam incident angle dependence of the dry etching resist mask 5 used at this time during argon ion etching. Thus, the angle of incidence of argon ions is from 0 degree to 80 degrees.
When the incident angle changes to 60 degrees, the maximum etching rate increases to 2.7 times that of the material to be etched 1 at an incident angle of 60 degrees, and the selectivity at the time of etching decreases. In this case, it is necessary to increase the thickness of the resist mask 5 and the shape change of the mask at the time of etching is large. Thus, it can be seen that without the carbon-based filler, it is not suitable as a resist mask material for argon ion etching.

Comparative Example 2 The dependency of the etching rate on the incident angle of argon ions was also measured for a carbon film. The result is shown in FIG. A carbon film formed by a sputtering method was used. From 0 ° to 40 °, the etching rate of the sputter carbon film is smaller than that of alumina titanium carbide or the resist mask material used in Example 1, and shows a good result. The difference in the case of Bonn membrane is
The change is smaller than the difference from the case of Comparative Example 1, and it can be seen that the resist mask material of Example 1 has an etching resistance close to that of sputter carbon. However, this sputter carbon has an extremely low film formation rate of 0.2 μm or less per hour, and has a practical film thickness (1 μm) required as a mask.
Considering that it takes too much time to form the film to a thickness of about 0 μm) and that it is difficult to form a pattern as a mask, it is not practical.

Example 5 A wafer on which a thin-film head element was formed was cut into head blocks.
To produce a rotary floating type thin film magnetic head. The thin-film head element was formed by a known film forming technique. The thin film magnetic head of the rotary levitation type obtained in this way is installed in a known magnetic disk device having a plurality of magnetic disks and a plurality of magnetic heads arranged corresponding to the thin-film magnetic head, and the performance characteristics are evaluated. As a result, excellent characteristics could be obtained in a high-density magnetic disk device having a small flying height of the head.

In the above embodiment, processing of the magnetic head slider has been mainly described. However, it goes without saying that the present invention can be used for general fine processing that requires dry etching such as fine processing of permalloy. Absent. In a sixth embodiment, an example of manufacturing a thin-film magnetic head by processing the track width of the magnetic head will be described.

Embodiment 6 Hereinafter, a manufacturing example in which the dry etching fine processing of the present invention is applied to the track width processing of a thin-film magnetic head will be described with reference to FIGS. 4 to 7. FIG. 4 is a sectional view showing a manufacturing process of the element of the thin film magnetic head. FIG. 5 shows the first photoresist pattern 3 appearing on the non-magnetic substrate 41 during the manufacturing process of FIG. FIG. 7 is a plan view schematically showing the second photoresist pattern 48, and FIG. 7 is a plan view of the lower thin-film magnetic head element 40 centering on the upper core layer 49 formed according to the present invention.

As shown in FIG. 4, the steps up to the step of forming the upper core layer 49 over the entire surface of the substrate 41 are the same as the steps of manufacturing a conventional thin-film magnetic head. That is, as shown in FIG. 4A, which is a vertical side view, a magnetic film is sputtered on the non-magnetic substrate 41 and the lower core layer 42 is formed by a photo-etching technique. Next, an insulating film is formed by a sputtering method, and the gap layer 43 is formed by using a photoetching technique. Subsequently, the organic resin is spin-coated, and then heat-cured,
The insulating film 44 is patterned by photo-etching technology.
And Further, a conductive film is sputtered and patterned spirally using a photo-etching technique to form a coil 45. An organic resin is formed on the coil 45 in the same manner as described above, and is patterned to form an insulating film 46. Then, a magnetic film is sputtered over the entire surface of the substrate to form a uniform upper magnetic layer 47.

The upper magnetic layer 47 thus formed
Was formed in the upper core layer 49 by dry etching according to the following procedures (1) to (8). (1) On the substrate on which the magnetic film 47 for the upper core was formed, the resin composition for a resist mask having the composition used in Example 1 for forming the resist mask 2 for dry etching was formed by a spin coating method. Film. (2) Photoresist containing silicon (for example, RU-16 manufactured by Hitachi Chemical Co., Ltd.) on the resist mask 2
00P) is applied and baked, and a first photoresist pattern 3 shown in FIG. 5 is formed using a photomask (not shown) having a rectangular pattern having a track width W as one side. . This state is shown in a vertical side view of FIG. 4A and a front view of FIG. 4B (head gap side).
Shown in

(3) Next, the resist mask 2 for dry etching is patterned by a reactive ion etching method using oxygen using the first photoresist 3 as a mask.

(4) Next, the first photoresist 3 is peeled off. (5) A second photoresist 48 (FIG. 6) that partially overlaps the pattern of the resist mask 2 for dry etching.
Is formed). This state is shown in a vertical sectional side view of FIG. 4C and a front view (head gap side) of FIG. 4D. (6) The magnetic film 47 is dry-etched (argon ion) using the dry etching resist mask 2 and the second photoresist 48 as a mask. This is the fine processing step by dry etching of the present invention.

(7) The second photoresist 48 is peeled off. This state is shown in a vertical side view of FIG. 4E and a front view (head gap side) of FIG. 4F. (8) The resist mask 2 for dry etching is peeled off. This state is shown in a vertical side view of FIG. 4 (g) and a front view (head gap side) of FIG. 4 (h). Thus, the magnetic film 47 is selectively dry-etched, and the upper core 49 shown in FIG. 7 is obtained. The leading end of the upper core 49 has the track width W, and the thin-film magnetic head 40 is obtained. The variation of the track width W thus formed is ± 1.
It can be kept within 0%.

Next, a specific embodiment will be described, and the description will be given again according to FIG. First, a 300-element thin-film magnetic head was formed on a non-magnetic substrate 41 having a diameter of 3 inches in the plane of the substrate by the following procedure. Permalloy is sputtered over the entire surface of the substrate 41 to a thickness of 1.5 μm and patterned by a photo-etching technique to form a lower core layer 42.
Next, alumina is formed to a thickness of 0.5 μm by a sputtering method, and the gap layer 43 is formed by using a photo-etching technique. Subsequently, a polyimide resin is spin-coated, then heat-cured, and patterned by a photo-etching technique to form an insulating layer 44 having a thickness of 2 μm. Further, Cu is sputtered to a thickness of 1.5 μm and spirally patterned using a photo-etching technique to form a coil 45. A polyimide resin is again formed on the coil 45 to a thickness of 2.5 μm and patterned to form an insulating layer 46. Then, a uniform upper magnetic film 47 is formed by sputtering permalloy. A resist mask 2 for dry etching was spin-coated to a thickness of 3 μm on a substrate having a pattern obtained in this manner, using the resin composition for a mask of the composition used in Example 1.

The patterning of the resist mask 2 for dry etching was performed as follows. That is, an organic silicon-based photoresist (trade name: RU-, manufactured by Hitachi Chemical Co., Ltd.)
1600 P) was applied to a thickness of 4 μm, dried, exposed and developed using a mask having a rectangular pattern of 8 μm × 40 μm to obtain a first photoresist 3. Next, the exposed portion of the resist mask 2 for dry etching is removed by reactive ion etching using oxygen, and the remaining photoresist is stripped with a stripping solution. Thus, the desired pattern of the resist mask 2 for processing the track width was obtained.

Next, on the substrate, a second pattern partially overlapping the pattern of the resist mask 2 for dry etching.
Is formed (a mask pattern 48 having the shape shown in FIG. 6). This second photoresist 48
Was formed by applying and drying using OFPR-800 (trade name, manufactured by Tokyo Ohka Kogyo Co., Ltd.) to form a film having a thickness of 10 μm, and performing exposure and development through a mask (not shown). Using the photoresist 48 and the resist mask 2 for dry etching as a mask, a permalloy film (upper magnetic layer)
The exposed portions of 47 are removed by ion etching of argon. Then, the second photoresist 48 is removed with a stripper. Finally, the dry etching resist mask 2 remaining in the rectangular shape is removed with a stripping solution. As a stripper,
A commercially available alkaline stripping solution was used.

The variation of the track width W in the substrate surface of the magnetic head element thus obtained was 7.8 ± 0.75 μm, indicating excellent processing accuracy. The write and read performances of the thin-film magnetic head manufactured using this element were satisfactory in practical use. In the above embodiment, argon ions were described as typical examples of rare gas ions for dry etching. However, fine processing can be performed with xenon ions to some extent, and other rare gases can also be used. .

[0057]

According to the microfabrication method using the resist mask resin composition for dry etching of the present invention, when performing dry etching using a rare gas ion beam represented by argon, selection of a material to be etched is performed. Since the ratio can be increased, the resist mask material can be made thinner than before, and the processing accuracy can be greatly improved. Therefore, it can be used not only in precision processing of a magnetic head but also in various other fields requiring fine processing by dry etching, and it is enormous that it can contribute industrially.

[Brief description of the drawings]

FIG. 1 is a process diagram of microfabrication according to one embodiment of the present invention, which is a precision process diagram of a head slider using a resist mask for dry etching without photosensitivity.

FIG. 2 is a process diagram of fine processing according to another embodiment of the present invention, and is a process diagram of precision processing of a head slider using a resist mask for dry etching provided with photosensitivity.

FIG. 3 is a characteristic curve diagram showing a relationship between a selectivity of a material to be etched and a resist mask in dry etching and an argon ion incident angle dependency.

FIG. 4 is a manufacturing process diagram of the thin-film magnetic head according to one embodiment of the present invention.

FIG. 5 schematically shows a plan view of a first photoresist pattern in a manufacturing process of the thin-film magnetic head.

FIG. 6 shows a second example of the manufacturing process of the thin-film magnetic head.
1 schematically illustrates a plan view of the photoresist pattern of FIG.

FIG. 7 schematically shows a plan view of a thin-film magnetic head element.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Material to be etched (head slider substrate) 2 ... Resist mask for dry etching (resin composition) 3 ... Photoresist (first photoresist) 4 ... Photoresist patterned 5 ... Resist mask for dry etching patterned 5 ': dry-etched resist mask 6: dry-etched head slider material 40: thin-film magnetic head element 41: non-magnetic substrate 42: lower magnetic layer 43: insulating film (gap layer) 44, 46: organic insulation Layer 45: Coil pattern 47: Upper magnetic layer (permalloy) 48: Second photoresist 49: Upper core W: Track width

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akiko Mizushima 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi, Ltd.Production Technology Laboratory (72) Inventor Saburo Suzuki 2880 Kozu, Kofu, Odawara-shi, Kanagawa Hitachi, Ltd. Inside the Odawara Plant (72) Inventor Hiroshi Ishizaki 2880 Kozu, Kozuhara City, Kanagawa Prefecture Inside Hitachi, Ltd.Odawara Plant (72) Inventor Hiroshi Ikeda 2880 Kozu, Kozuhara, Odawara City, Kanagawa Prefecture Inside Hitachi, Ltd.Odawara Plant (56) References JP-A-1-285946 (JP, A) JP-A-55-9538 (JP, A) JP-A-60-6942 (JP, A) JP-A-62-144159 (JP, A) JP-A-63-282732 (JP, A) JP-A-62-113135 (JP, A) JP-A-1-140145 (JP, A) JP-A-1-201337 (JP, A) (58)査the field (Int.Cl. ^6, DB name) G03F 7/004 501 G03F 7/038 G03F 7/40 521

Claims (8)

(57) [Claims] 1. A resist mask pattern having a predetermined shape is formed on a predetermined substrate to be etched, and when the substrate is finely processed by dry etching, the resist mask pattern is replaced with a matrix having an aromatic group in a molecule.
A resist mask mainly composed of a polymer
Disperse and contain carbon filler in matrix polymer
A dry etching resist mask or a carbon-based filler dispersed in the resist mask;
Reduce the weight by weight ratio to the matrix polymer
And the dry etching resist comprises 5%.
Formed using disk, microfabrication method by dry etching comprising the object to be etched substrate by physical etching using argon ions with a dry-etching. 2. A fine processing method by dry etching according to claim 1, wherein comprising a step of dry etching under conditions etch rate ratio to the resist mask of the etching target substrate is 0.8 or more. 3. The substrate to be etched is a magnetic head slider, the resist mask pattern is formed at a position corresponding to a slider sliding surface, and the substrate is selectively etched by dry etching to form a slider rail portion. microfabrication method by dry etching according to claim 1, wherein comprising a step of processing the magnetic head slider to be. 4. The substrate to be etched is a magnetic head substrate having a magnetic metal film formed on its surface, the resist mask pattern is formed at a position corresponding to the track width of a magnetic head, and the magnetic metal is formed by dry etching. film is selectively etched to a fine machining method using dry etching according to claim 1, wherein comprising a step of processing the track width of the magnetic head. 5. A matrix matrix having an aromatic group in a molecule.
Resin group mainly composed of limer and solvent that dissolves it
A carbonaceous filler in the resin composition.
Dry etching resist mass dispersed and contained
A dry resin composition, wherein the carbon-based filler comprises fine diamond powder having an average particle diameter of 0.15 μm or less.
A resist mask resin composition for etching . 6. The dry etching method according to claim 5 , wherein the content of the carbon-based filler dispersed in the resin composition is at least 5% by weight with respect to the matrix polymer and is contained together with the dispersant. Resist mask resin composition. 7. The resist mask resin composition for dry etching according to claim 5 , wherein the matrix polymer comprises at least one resin selected from the group consisting of a polyamic acid, a polyimide resin, a novolak resin and a polystyrene-based polymer. 8. The carbon-based filler has an average particle size of 0.1 μm.
The resist mask resin composition for dry etching according to claim 5, comprising carbon black of m or less.