JP2001330969A - Apparatus for removing photoresist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a space-saving apparatus for removing a photoresist in which ozonized water of a high concentration is rapidly and precisely produced, a photoresist unnecessitated in a photolithography step in the production of a semiconductor, a liquid crystal or the like can be removed with good production efficiency and an aerator and a vapor-liquid separation tower are unnecessary. SOLUTION: In the apparatus for removing a photoresist, the photoresist pattern layer of each photoresist laminate unnecessitated after the etching of the photoresist laminate with the photoresist pattern layer formed on a substrate is removed with ozonized water produced by separating raw water and gaseous ozone using a gaseous ozone permeation membrane being gas- permeable but liquid-impermeable and dissolving gaseous ozone in the raw water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an apparatus for removing unnecessary photoresist in a photolithography process in the production of semiconductors and liquid crystals.

[0002]

2. Description of the Related Art In the manufacture of semiconductors and liquid crystals, a peeling step of removing a photoresist that is no longer required in a photolithography step is repeatedly performed. In this photoresist stripping process, there is a problem in that a large amount of chemical solution is used, and high-temperature processing imposes a burden on air conditioning in a clean room. With concern about the environment increasing, ozone water is used as an alternative method. Attention has been focused on the resist stripping process.

In the resist stripping process using ozone water, the relationship between the concentration of ozone water and the stripping speed has been studied, and it has been found that increasing the concentration of ozone water is very effective in stripping speed. (The 8th Annual Meeting of the Ozone Society of Japan Annual Lectures, pp. 14-16: 1998,
Issued on March 3rd.

When examining the resist stripping using ozone water, as the ozone water generation method, a conventional method such as a bubbling type in which ozone gas (bubbles) is injected into water or a mixer (ejector) is used. In the case of the aeration method, the ratio between the gas phase (ozone) concentration and the liquid phase (ozone water) concentration, that is, the distribution coefficient is uniquely determined by the temperature. Therefore, it is difficult to set the ozone water concentration high,
Further, there is a problem that the efficiency of dissolving ozone gas in water is low, and it is difficult to properly control the concentration.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned problems, and has been made in consideration of the need for removing unnecessary photoresist in a photolithography process in the production of semiconductors and liquid crystals. To provide a photoresist removal device that can remove photoresist with good production efficiency by generating high-concentration ozone water with high accuracy and that does not require an aeration facility or a gas-liquid separation tower. It is.

[0006]

SUMMARY OF THE INVENTION According to the present invention, after a photoresist laminate having a photoresist layer formed on a substrate is subjected to an etching treatment, the photoresist layer of the laminate which has become unnecessary is treated with ozone water. The ozone water is used to separate the raw water and the ozone gas with an ozone gas permeable membrane that passes only the gas and prevents liquid permeation, and passes the raw water through the ozone gas permeable membrane. The photoresist removing apparatus is manufactured by dissolving the ozone gas therein (claim 1). At this time, it is preferable that the ozone gas permeable membrane is formed in a hollow tubular shape (tube shape) and installed in a storage container (claim 2). Further, it is preferable that the ozone gas permeable film is formed of a fluorine resin or a silicon resin.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings shown in FIG. 1, but the present invention is not limited to these embodiments.

FIG. 1 shows a conceptual diagram of an apparatus for removing a photoresist according to the present invention. In the drawing, reference numeral 2 denotes ozone water (OW).
Indicates an ozone dissolving unit (ozone water dissolving module) for generating, and -1 indicates a photoresist removal tank. -2
Indicates a photoresist laminated body, and -3 indicates a substrate after the etching process from which the photoresist was removed. After the ozone water is generated in the ozone dissolving section 2, the ozone water is transferred to and stored in the photoresist removal tank-1. By immersing the photoresist laminate 2 in high-concentration ozone water stored in the photoresist removal tank 1, only the photoresist layer can be removed, and only the etched base 3 can be taken out. The ozone water in the photoresist removing tank-1 is recycled to the ozone dissolving section 2 again in order to secure a desired constant concentration.

In the present invention, the substrate of the photoresist laminate is, for example, a silicon wafer in the case of a semiconductor, or a material film of a glass plate in the case of a liquid crystal display panel. The configuration is not limited as long as the configuration satisfies the above configuration. Also, as an embodiment of the means for removing the photoresist layer using ozone water, a circulation type using a batch type of the removal tank is mentioned, but is not necessarily limited to this method. For example, a method of making contact using a spray method, a curtain flow method, or the like can also be used.

Next, FIG. 2 shows details of the ozone water generating portion in the photoresist removing apparatus according to the present invention. The ozone water generating portion is an ozone dissolving section (ozone dissolving module) for dissolving ozone gas (OG) into raw water (W ′) indicated by reference numeral 2 in the drawing to generate ozone water (OW). And a degassing unit 1 for degassing dissolved gas from raw water (W) such as ion-exchanged water or ultrapure water to facilitate the incorporation of ozone gas.
And the primary ozone water (O
W), a required amount of dissolved ozone is degassed to control the dissolved ozone gas concentration, and an ozone concentration adjusting unit 3 for generating secondary ozone water (OW ′) finally used is added. A first ozone detector 4 for detecting the concentration of dissolved ozone gas in the primary ozone water (OW) generated by the ozone dissolving section 2 as required;
The secondary ozone water (O
And a second ozone detector 5 for detecting the concentration of dissolved ozone gas W ′).

The degassing section 1 degass a dissolved gas from raw water (ion-exchanged water, ultrapure water, etc.) (W) in which ozone gas is dissolved, so that an extra gas other than ozone is not dissolved in ozone water. And to facilitate the dissolution of ozone gas, similar to known vacuum deaerators,
A vacuum vessel 11, a vacuum pump (not shown) for reducing the pressure inside the vacuum vessel 11, and a deaeration tube 12 installed in the vacuum vessel 11 for flowing the raw water (W)
Etc.

Tube 12 for deaeration used in deaeration section 1
Is formed into a hollow tube (tube shape) having a required inner diameter and length using a known material that allows only a gas made of, for example, a fluororesin polymer or a silicon-based resin polymer to pass through and prevent liquid from permeating. The one end opening is connected to a supply source (water storage tank) 10 of raw water (W) as a liquid inlet and the other end is connected to the ozone dissolving section 2 as a liquid outlet. While controlling the pressure inside the vacuum vessel 11 with a vacuum pump or the like, the raw water
Is passed from the liquid inlet to the inside of the degassing tube 12, whereby the dissolved gas is degassed from the raw water (W) while coming out of the liquid outlet.

Next, the details of the ozone dissolving module are shown in FIG.
Shown in The ozone dissolving unit 2 is for dissolving ozone gas into raw water to generate ozone water. Specifically, the ozone dissolving unit 2 dissolves ozone gas (OG) into raw water (W ′) from which dissolved gas has been degassed in advance. To generate primary ozone water (OW), and a container 21, a raw water (W ′) installed in the container 21 from which dissolved gas has been degassed in advance, and an ozone generator 6. An ozone dissolving module is composed of an ozone gas permeable membrane 22 and the like for isolating ozone gas (OG) supplied from the apparatus.

The ozone gas permeable film 22 used in the ozone dissolving section 2 is a film material that allows only gas to pass and prevents liquid from permeating, preferably has excellent corrosion resistance and deterioration resistance to ozone gas and selectively transmits ozone gas. A film material having the property of causing the resin to be formed, specifically, a fluorine-based resin material or a silicon-based resin material, more specifically, a tetrafluoroethylene-based resin polymer which is a fluorine-based resin material, such as tetrafluoroethylene resin (PTFE) or , Perfluoroalkoxy resin (PF
A), a hollow film having a flat membrane shape or a required inner diameter and length using a membrane material such as methylsilicone rubber or the like for a silicone resin material such as a fluororesin material such as fluoroethylene propylene resin (FEP) or a fluorine rubber material. (Water) supplied from the deaeration unit 2 and ozone gas (OG) supplied from the ozone generator 6 are placed in the container 21 so as to be separated from each other. The supply line of the ozone gas (OG) is pressurized in a state where the ozone gas (OG) is in contact with (W ′), that is, the ozone gas (OG) is allowed to pass through the ozone gas permeable membrane 22 while being pressurized.

That is, when the ozone gas permeable film 22 is formed in a hollow tube (tube shape), the ozone gas permeable film 22 formed in a tube shape is installed in the storage container 21 and the ozone gas (OG) is stored in the storage container 21. ) Is filled or circulated, and the raw water (W ′) is filled or circulated in the ozone gas permeable membrane 22 formed in a tubular shape, or conversely, the raw water (W ′) is filled in the storage container 21. Alternatively, the ozone gas (OG) is filled or circulated in the ozone gas permeable film 22 formed in a tubular shape. The storage container 21 may be formed in a tank shape or a hollow tube shape having a required length.

Incidentally, the ozone dissolving unit 2 of the illustrated embodiment
Is a plurality of ozone gas permeable membranes 2 formed in a tube shape.
The two ends of each of the two are fused or bonded to each other, and the storage container 21 is formed in a substantially cylindrical shape having airtightness with a material excellent in ozone resistance such as stainless steel. The ozone gas permeable membrane 22 is housed, the one end opening of the tubular ozone gas permeable membrane 22 is located next to the liquid inlet 21a of the housing container 21, and the other end is opened to the liquid outlet 21b of the housing container 21, and the ozone dissolving module is installed. The liquid outlet 21a of the container 21 is connected to the degassing unit 1
To the inlet of the raw water (W ′), and the liquid outlet 21b of the container 21 is connected to the ozone concentration controller 3 or the storage tank 7 to serve as the outlet of the primary ozone water (OW). is there.

An ozone generator 6 is connected to a gas inlet 21c formed on the side opposite to the liquid inlet 21a of the container 21. The inside of the container 21 is filled with ozone gas (OG) supplied from the ozone generator 6. High pressure from outside,
In this state, the raw water (W ′) degassed in the degassing section 1 is stored in the tubular ozone gas permeable membrane 22 through the liquid inlet 21a by flowing the ozone gas (OG) in a countercurrent manner. High-pressure ozone gas (O
G) dissolves in the raw water (W ′) through the tubular ozone gas permeable membrane 22, and the liquid outlet 21b of the storage container 21
Primary ozone water (OW) is generated while coming out of
Excess ozone gas (OG) is discharged from the gas outlet 2 of the container 21.
It is designed to be discharged from 1d to the outside.

It is to be noted that, contrary to the embodiment shown in FIG.
Ozone gas (OG) is circulated inside the container 2 and the container 2
The ozone gas (OG) may be dissolved into the raw water (W ′) through the tubular ozone gas permeable membrane 22 by flowing the raw water (W ′) from the first gas inlet 21 c.

The dissolved ozone gas concentration of the primary ozone water (OW) generated in the ozone dissolving section 2 is managed (monitored) by a first ozone detector 4 connected to the ozone dissolving section 2. Usually, the concentration of dissolved ozone gas in the primary ozone water (OW) generated in the ozone dissolving section 2 becomes considerably high.
The ozone water concentration can be controlled by appropriately adjusting the dissolved ozone gas concentration by the ozone concentration adjusting unit 3.

The ozone concentration adjusting section 3 degass a required amount of dissolved ozone from the primary ozone water (OW) generated in the ozone dissolving section 2 (finally uses the dissolved ozone) and ultimately uses the secondary ozone water (O).
W ′) for controlling the concentration of the dissolved ozone gas, a pressure reducing vessel 31, a vacuum pump (not shown) for reducing the pressure inside the pressure reducing vessel 31, and a pressure reducing vessel 31.
The degassing tube 32 is provided in the decompression tube 31 in a state where the pressure inside the decompression container 31 is reduced.
The primary ozone supplied from the ozone dissolving unit 2 is supplied to the decompression container 31 while the primary ozone water (OW) supplied from the ozone dissolving unit 2 is circulated inside the degassing tube 32. The primary ozone water (OW) generated in the ozone dissolving section 2 by supplying water (OW)
, A required amount of dissolved ozone gas is degassed, the dissolved ozone gas concentration is adjusted, and secondary ozone water (OW ′) having a desired ozone gas concentration is generated.

The deaeration tube 32 used in the ozone concentration adjusting section 3 is a film material that allows only gas to pass and prevents liquid from permeating, preferably a film material that is excellent in corrosion resistance and deterioration resistance to ozone gas. Specifically, a fluorine-based resin material or a silicon-based resin material, more specifically, a tetrafluoroethylene-based resin polymer which is a fluorine-based resin material, for example, tetrafluoroethylene resin (PTFE) or perfluoroalkoxy resin (PFA) Using a film material made of methylsilicone rubber or the like for a silicone resin material, such as fluorinated ethylene propylene resin (FEP) or fluorine rubber material,
It is formed in a hollow tube (tube shape) having a required inner diameter and length, and is installed inside the decompression vessel 31.

In the case of the illustrated embodiment, one end opening of the degassing tube 32 is connected to the ozone dissolving section 2 as a liquid inlet for primary ozone water (OW), and the other end opening is used as a liquid outlet. The primary ozone water (OW) generated in the ozone dissolving unit 2 while being connected to the storage tank 8 (which can also be a photoresist removal water tank-1) and controlling the inside of the vacuum container 31 with a vacuum pump or the like is removed. By flowing the liquid from the liquid inlet to the inside of the degassing tube 32, the primary ozone water (O
A required amount of dissolved gas is degassed from W), the dissolved ozone gas concentration is adjusted, and as a result, secondary ozone water (OW ′) having a desired ozone gas concentration is generated.

The dissolved ozone gas concentration of the secondary ozone water (OW ′) generated by the ozone concentration adjusting section 3 is managed (monitored) by the second ozone detector 5 connected to the ozone concentration adjusting section 3. The second ozone detector 5 and the first ozone detector 4 for managing (monitoring) the dissolved ozone gas concentration of the primary ozone water (OW) generated by the ozone dissolving unit 2 are switched by a switching valve (not shown) or the like. Thus, it is possible to use only one ozone detector as the ozone treatment device. As the ozone detectors 4 and 5, commercially available ozone detectors such as a continuous measurement type dissolved ozone monitor using an ultraviolet absorption method can be used.

As the ozone generator 6 in the present invention, a commercially available one such as a silent discharge type in which air or oxygen gas is passed through a silent discharge to generate ozone gas or an ultraviolet irradiation type is used. Can be used.

Next, an ozone water generation system using an ozone dissolution module (ozone dissolution unit) 2 will be described with reference to FIG.
This will be described with reference to FIG. The same components as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.
As a raw water (W), tap water adjusted to the same temperature as room temperature was used, and a pump (not shown, GY14 manufactured by Nikkiso Co., Ltd.) was used.
-PYTE-45 / 54) through the flow meter 91 to form a tubular ozone gas permeable membrane 2 of the ozone dissolving module 2
2, while using oxygen gas as a raw material of ozone gas (OG) and passing through an ozone generator 6 through a flow meter 93.
(OZG-600 manufactured by Techno Echo Co., Ltd.) and the ozone gas concentration is measured using an ozone gas detector (0
After monitoring by ZR911) 94, the water is supplied to the inside of the ozone dissolving module 2 (the inside of the container 21), and is dissolved in the raw water (W) through the tubular ozone gas permeable membrane 22. The ozone gas concentration of the generated ozone water (OW) is measured with an ozone gas detector (0ZR911 manufactured by Riko Kagaku Co., Ltd.).
Detect in 4).

Although the ozone generator has been described in detail above, how the generated ozone water is applied to the apparatus of the present invention can be appropriately selected as described above. That is, the ozone water storage tanks 7 and 8 and the like may be used as a photoresist removal tank as they are, or those once stored in these tanks may be used in another method as described above.
It may be used as a removal method using ozone water.

<Example 1 of Ozone Water Generation> The ozone dissolving module 2 shown in FIG. 3 and the system shown in FIG.
A bundle of 150 hollow tubes (tubes) made of tetrafluoroethylene resin (PTFE) having an inner diameter of 0.5 mmφ, a thickness of 0.15 mm, and a length of 3.5 m in accordance with (American Wired Gauge Standard) 24 is used. The inner diameter 100
tap water adjusted to the same temperature as room temperature (22 ° C.) in a tubular ozone gas permeable membrane 22 through a liquid inlet 21 a of the ozone dissolving module 2 through a stainless steel container 21 having a diameter of 170 mm and a length of 170 mm. And the ozone gas having a concentration of 31 mg / L is supplied from the gas inlet 21c of the ozone dissolving module 2 at a flow rate of 130 mL / min countercurrent to the flow of the tap water, and the flow rate of the tap water is changed stepwise. The ozone gas concentration of the generated ozone water was measured.

From the measurement results, the flow rate was 25 mL / min.
Instantaneously yields a high concentration of 16.5 mg / L of ozone water, and the ratio between the gas phase concentration and the liquid concentration, that is, the distribution coefficient (liquid ozone gas concentration / gas ozone gas concentration) is 25 m
Aeration method with 0.53 at L / min (Ozone water generation example 3
) Was about 2.5 times the distribution ratio.

<Example 2 of Ozone Water Generation> The tube-shaped ozone gas permeable membrane 22 has an inner diameter of 1.0 mmφ and an inner diameter of 2.0 m.
Ozone generated in the same manner as in Ozone water generation example 1 except that ten silicon hollow tubes (tubes) manufactured by Toyobo Engineering Co., Ltd. having a diameter of 0.5 mm, a thickness of 0.5 mm, and a length of 3.5 m were used. The ozone gas concentration of water was measured.
As a result, ozone water having an ozone gas concentration of 16.2 mg / L was obtained, and the distribution coefficient was 0.52, which was about 2.5 times that of the aeration method (see ozone water generation example 3). It was proved that.

<Example 3 of ozone water generation> Instead of the ozone dissolving module, a pipe made of polyvinyl chloride resin having an inner diameter of 60 mm and a length of 1.0 m was set in a vertical shape, and a ceramic sintered filter was passed through a lower part thereof. Ozone gas is spouted to form bubbles, and tap water adjusted to room temperature (20 ° C.) is flowed from the top at a flow rate of 25 mL / min.
And ozone water generation example 1 was carried out except that the ozone gas concentration 10 minutes after the start of aeration was measured. As a result, ozone water having an ozone gas concentration of 6.5 mg / L was obtained. From this comparison, the ozone gas concentration was 0.21 in the aeration method, and the flow rate of the ozone water generation example 1 with the same ozone gas concentration was 25 mL / L. min, ozone water concentration 1
The concentration was 39% as compared with 6.5 mg / L. The results are shown in Table 1.

[0031]

[Table 1]

<Example, Photoresist Removal Operation> 10
A positive resist for TFT (trade name “OFPR-PR13”, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is coated on a 00 × 1000 mm square glass plate by a spin coater (trade name “1H-DXNI”).
I ", manufactured by Mikasa Co., Ltd.)
After heating and drying for a minute, a photoresist layer was laminated. By the above method, a sample of the photoresist laminated body was obtained.
Incidentally, the thickness of the photoresist layer was 1.1 μm. Using the sample, the sample was immersed in ozone water in a photoresist removal tank filled with the ozone water created in the ozone water generation examples 1 to 30 for 30 minutes, and the removal condition of the photoresist layer was confirmed. As a result, when the ozone water generation examples 1 and 2 were used, the photoresist layer was completely removed.
m had been removed.

[0033]

According to the photoresist removing apparatus of the present invention, the photoresist can be removed using high-concentration ozone water. Of the photoresist can be removed. Further, in the apparatus of the present invention, the ozone water separates the raw water and the ozone gas by an ozone gas permeable membrane that passes only gas and prevents liquid permeation, and dissolves the ozone gas into the raw water through the ozone gas permeable membrane. Since ozone gas toxic to humans is not aerated in the raw material water, safe and high-concentration ozone water can be efficiently generated with simple mechanisms and equipment.

Further, since the ozone gas permeable membrane is formed in a hollow tubular shape and the ozone gas permeable membrane is installed in the container, the ozone gas can be easily dissolved in the raw water by a simple structure and the ozone gas having a high concentration can be obtained. Can be generated.

Further, since the ozone gas permeable film is formed of a fluororesin, it is excellent in corrosion resistance and deterioration resistance to ozone gas, and can selectively transmit ozone gas. Can be generated.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an embodiment of the apparatus of the present invention.

FIG. 2 is an explanatory view of an ozone water generating portion of the apparatus of the present invention.

FIG. 3 is a schematic diagram showing an embodiment of an ozone dissolving module which is an ozone water generating part in the apparatus of the present invention.

FIG. 4 is an explanatory view showing an embodiment of an ozone dissolving system which is an ozone water generating part in the apparatus of the present invention.

[Explanation of symbols]

-1: Photoresist removal tank -2: Photoresist laminate -3: Substrate after etching treatment with photoresist removed 1: Degassing section 11: Vacuum container 12: Degassing tube 2: Ozone dissolving section 21: Storage container 22: Ozone gas permeable membrane 3: Ozone concentration adjustment unit 31: Decompression container 32: Degassing tube 4: First ozone detector 5: Second ozone detector 6: Ozone generator 7: Storage tank 8: Ozone water storage Tank 10: raw water supply source (water storage tank) W, W ': raw water OG: ozone gas OW: primary ozone water OW': secondary ozone water

Claims (3)

[Claims] 1. A photoresist removing apparatus for removing a photoresist layer of an unnecessary laminate using ozone water after etching a photoresist laminate having a photoresist layer formed on a substrate. The ozone water is generated by isolating the raw water and ozone gas by an ozone gas permeable membrane that passes only gas and prevents liquid permeation, and dissolves the ozone gas into the raw water through the ozone gas permeable membrane. A photoresist removing apparatus. 2. The photoresist removing apparatus according to claim 1, wherein the ozone gas permeable film is formed in a hollow tubular shape, and the ozone gas permeable film is installed in a container. 3. The photoresist removing apparatus according to claim 1, wherein the ozone gas permeable film is formed of a fluorine-based resin or a silicon-based resin.