JPH05158246A - Method for developing photosensitive resist - Google Patents

Abstract

PURPOSE:To prevent the occurrence of fine pits in the surface of a photosensitive resist when the resist is developed by spraying or dropping rotation. CONSTITUTION:When a photosensitive resist 2 is developed by spraying or dropping rotation, a protective layer 5 is formed on the surface of the resist 2 before development. Since splashes 4 of a developer do not come into contact with the surface of the resist 2, the occurrence of fine pits is prevented.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for developing a photosensitive resist.

[0002]

2. Description of the Related Art As a conventional method for developing a photosensitive resist, so-called spray development is used, in which a developing solution is pressurized and sprayed from a nozzle to be atomized to be sprayed on the resist surface, or a developing solution is applied through a small hole to the resist surface. There is a method of so-called dropping rotation method or the like in which the substrate is rotated and the developing solution is spread over the entire resist after the dropping.

There are other types such as so-called dip type and ultrasonic type.

Of the above, particularly when the resist thickness (resist thickness) is large, it is necessary to intrude the development in the depth direction of the portion dissolved by the developing solution, and therefore the spray method is superior. ..

Further, the spray type is capable of continuous development, washing, etc. by conveyor conveyance and the like, is easy to automate, and has high uniformity of development. Therefore, for developing a thick film such as a so-called dry film having a large resist thickness, The spray type is the mainstream.

On the other hand, when the resist thickness is thin, the dropping rotation type is mainly used.

[0007]

However, in the spray-type or drop-rotation type developing method, a large amount of developer droplets are generated, and the resist-laminated substrate is applied to the surface of the resist before it enters the developing chamber. The developer splashes,
It becomes a small droplet of the developing solution, which stays on the resist surface for a long time, and minute concave round “dents” are generated in the undissolved portion of the resist surface (the portion that remains as a pattern after development).

This is because the small droplets of the developing solution dissolves the non-dissolved portion of the resist, although a small amount thereof. Therefore, when the resist is used as an etching resist, there is no particular problem, but the resist is not particularly problematic. When used as a mold material, for example, as a mold material for a nozzle of an ink jet or the like, minute depressions on the resist surface also pose a problem because they greatly affect the ink ejection performance.

The applicant of the present invention has proposed in Japanese Patent Laid-Open No. 253457/1987 as means for manufacturing an ink jet using the resist as a mold material.

An object of the present invention is to provide a method for developing a photosensitive resist which prevents the generation of minute depressions on the resist surface.

[0011]

SUMMARY OF THE INVENTION In the development of a spray-type or dropping-rotation type photosensitive resist, the present invention provides a protective layer on the surface of the photosensitive resist before the developing step of the photosensitive resist. It has a feature. Further, the protective layer is a liquid containing water as a main component, or the protective layer contains a surfactant.

By this means, it is possible to prevent the depression of the resist surface due to the splash of the developing solution, so that a relief image with a smooth surface can be obtained with high accuracy. Further, the protective layer can be easily applied at a low cost, and the protective layer can be quickly provided on the resist surface without any defects.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings.

1 to 9 are schematic diagrams for explaining the basic mode of the present invention.

FIG. 1 is a diagram in which droplets of a developing solution adhere to the protective layer provided on the resist surface after exposure.

FIG. 2 is a schematic view showing a photosensitive resist layer 2 laminated on a substrate 1 made of glass, silicon, ceramics, plastics, metal or the like.

The photosensitive resist used here is not particularly limited to liquid, dry film, negative type, positive type, etc., but a resist used as a mold material, for example, a positive type dry film (OZATEC R225 Hoechst Japan ( Ltd.)).

As a method for laminating the positive type dry film as described above, there is used a so-called laminating method in which a preheated substrate is subjected to thermocompression bonding with a heat roll.

Next, FIG. 3 is a diagram in which ultraviolet rays are irradiated from above the photomask 3 in order to print a pattern of a desired shape on the photosensitive resist layer 2.

For example, in the case of the above-mentioned positive type dry film resist (thickness: 25 μm), 25 mJ / cm ² to 30
UV rays of 0 mJ / cm ² are applied by mask aligner etc.
Irradiate on a positive dry film.

Reference numeral 21 denotes a portion which is shielded by the photomask and is not exposed, and 22 denotes an exposed portion.

Next, FIG. 4 is a schematic diagram of a general spray type developing apparatus used in this embodiment.

The developing device has a conveying means such as a conveyor from the loader to the unloader, and can develop a substrate on which resists are continuously laminated.

To explain the outline of the developing process by the present developing device, first, the substrate carried out from the loader section (a) is
It is carried into the developing chamber (c) through the preliminary chamber (b).

In the developing chamber (c), a large number of nozzles for applying the developing solution to spray the developing solution in a mist state on the substrate are provided in multiple stages. Subsequently, the rinsing chamber (d) and the rinsing chambers (e) and (f) are provided with the same pressurizing means and nozzles as those in the developing chamber (c). It has the function of being sprayed on.

Furthermore, the drying chamber (g) has a draining means such as a so-called air knife or a spinner, and the structure in which the substrate dried by washing water is stored in the unloader section (h). Is becoming

For example, in the case of the above-mentioned positive type dry film (thickness: 25 μm), the development is performed under the following conditions, although it varies depending on the shape and size of the pattern.

Developer 1% (w / v) aqueous caustic soda solution w is weight (g), and V is volume (l). 1% (w /
v) is an aqueous solution of 10 g in 1 l.

Rinsing solution 0.5% aqueous caustic soda solution Spray pressure 0.5 kg / cm ^{2 to} 3 kg / cm ² Development time 30 seconds to 3 minutes Rinse time 30 seconds to 3 minutes Water washing 30 seconds to 9 minutes FIG. FIG. 4 is a diagram in which the droplets 4 of the developing solution are attached, and when the substrate discharged from the loader section (a) during the above-described development passes through the preliminary chamber (b), Developer droplets sprayed from the nozzle 4
FIG. 6 is a diagram in which the resist 2 has also come to the preliminary chamber (b) and has been attached to the resist 2 laminated on the substrate 1.

The droplet 4 of the developing solution attached as described above is
The exposed portion 22 of the resist will of course dissolve,
Since the unexposed portion 21 of the resist also has a slight dissolving effect, only the portion of the unexposed portion 21 to which the droplets 4 have adhered can be applied to other unexposed portions where droplets have not adhered. Compared to the pattern left after the development, the film is slightly thinned, and the concave round depression 23 is formed on the pattern.
Occurs. FIG. 6 shows this mode.

Usually, the size of the depression depends on the size of the droplet and is about 5 to 200 μm, and the depth is about 0.2 to.
It is about 2 μm. The depressions on such a pattern are
When the resist is used as an etching resist, it often does not cause a big obstacle, but when the resist is used as a mold material, a dent on the resist surface is transferred to the casting material side and a desired shape cannot be obtained, which causes a problem. There is.

In the present invention, as a means for solving the minute depressions on the resist 2 due to the above-mentioned droplets of the developing solution, as shown in FIG. 7, a protective layer 5 against the droplets of the developing solution is provided before the development. It is to give.

As shown in FIG. 1, the protective layer 5 applied on the resist completely shuts off the resist 2 and the developer droplets 4, or the developer droplets are diffused into the protective layer 5. The dissolving power is reduced, and the depressions 23 on the resist 2 as described above do not occur.

Further, by using water or a liquid containing water as a main component for the protective layer 5, it becomes possible to remove the resist 2 without changing the surface condition thereof and easily in the developing step, which is inexpensive. Thus, it is possible to easily prevent the depression 23 on the surface of the resist 2.

Further, by adding a trace amount of the surfactant to the protective layer 5, the protective layer 5 spreads quickly and without any defects on the surface of the resist 2 and exhibits the function as the protective layer 5.

As a concrete example, when the substrate 1 is unloaded from the loader section (a) shown in FIG. 4 to the preliminary chamber (b), a surfactant such as the surfactant Surfynol 44 is used.
Pure water containing 0% (manufactured by Nisshin Chemical Co., Ltd.) is dropped onto the resist 2 from a tube in which a large number of holes having a diameter of about 0.1 to 3 mm are arranged while the substrate 1 is transported. By applying it to the entire surface, even if the droplets of the developing solution are attached, they diffuse into the pure water containing the surfactant, and the effect of dissolving the unexposed portion of the resist 2 disappears. The depression can be prevented.

Next, the protective layer 5 previously applied as described above.
After entering the developing chamber (c), the developing solution is easily washed away by a shower of developing solution as shown in FIG. 8 to start development.

In FIG. 9, the exposed portion 22 of the resist 2 is dissolved by the developer and the unexposed portion 2 of the resist 2 is dissolved.
It is the figure where 1 remained. Needless to say, the remaining resist 2
No fine dents exist on the surface of No. 1.

Thereafter, the substrate 1 is rinsed, washed with water, and drained to complete the development.

Although a positive type dry film is used as the photosensitive resist in the above-mentioned embodiments, it is not necessarily limited to the positive type dry film, and a negative type dry film or a positive type liquid resist or a negative type liquid film is used. It is also effective for developing resists and the like.

Further, the use of the resist is not limited to the case of being used as a mold material, but also when it is used as a structural material constituting the nozzle wall of an ink jet channel, for example, the depression of the resist surface causes a problem. Is effective.

Further, not only the water-soluble resist as in the above-mentioned embodiment but also the solvent-developing type resist, the developing method of the present invention can be carried out by selecting an appropriate protective solution.

For example, in the case of a solvent-developing negative dry film, 1-1-1 trichloroethane is usually used as the developing solution. In this case, alcohol, glycols, etc. can be used in addition to water. is there.

Further, the protective layer is not limited to a liquid, and a resin film or the like may be used as long as it does not dissolve the resist and can be easily removed by the impact of the spray of the developing solution.

Further, in the above-mentioned embodiment, the spray method was used as the developing method, but also in the case of the dropping rotation method, the droplets of the developing solution when the substrate is rotated have the substrate resist in front of the developing chamber (c). The developing method according to the present invention is effective because it is deposited on the surface of the resist and causes depressions on the resist similar to those of the spray method described above.

[0046]

As described above, the developing method of the photosensitive resist of the present invention is a spray type or dropping rotary type developing method, and a protective layer is formed on the surface of the photosensitive resist before the developing step of the photosensitive resist. As a result, the depression of the resist surface due to the splash of the developing solution can be prevented, and the relief image can be obtained with a smooth surface and high accuracy.

By using a liquid containing water as a main component for the protective layer, the protective layer can be easily provided at a low cost.

By containing a surfactant in the protective layer, it is possible to quickly form the protective layer on the resist surface without any defects.

[Brief description of drawings]

FIG. 1 is a diagram in which droplets of a developing solution adhere to a protective layer provided on a resist surface after exposure.

FIG. 2 is a schematic diagram in which a photosensitive resist is laminated on a substrate.

FIG. 3 is a schematic diagram in which a photosensitive resist is subjected to pattern exposure.

FIG. 4 is a schematic diagram of a developing device.

FIG. 5 is a diagram in which droplets of a developer are attached in a conventional example.

FIG. 6 is a diagram showing a dent formed on a resist surface after development in a conventional example.

FIG. 7 is a view in which a protective layer according to the present invention is provided.

FIG. 8 is a schematic view showing development in the present invention.

FIG. 9 is a diagram in which development in the present invention is completed and a resist pattern remains.

[Explanation of symbols]

 1 substrate 2 photosensitive resist 3 photomask 4 developer splash 5 protective layer

Claims (3)

[Claims] 1. Development of a photosensitive resist of spray type or dropping rotary type, characterized in that a protective layer is provided on the surface of said photosensitive resist before the developing step of the photosensitive resist. Method. 2. The method of developing a photosensitive resist according to claim 1, wherein the protective layer is a liquid containing water as a main component. 3. The method for developing a photosensitive resist according to claim 1 or 2, wherein the protective layer contains a surfactant.