KR101799061B1 - Membrane cleaner and method for recycling membrane using the same - Google Patents

Membrane cleaner and method for recycling membrane using the same Download PDF

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KR101799061B1
KR101799061B1 KR1020150175830A KR20150175830A KR101799061B1 KR 101799061 B1 KR101799061 B1 KR 101799061B1 KR 1020150175830 A KR1020150175830 A KR 1020150175830A KR 20150175830 A KR20150175830 A KR 20150175830A KR 101799061 B1 KR101799061 B1 KR 101799061B1
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membrane
coating
cleaning
weight
present
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KR1020150175830A
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Korean (ko)
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KR20170068855A (en
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변경훈
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주식회사 원익큐엔씨
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    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
    • C11D7/02—Inorganic compounds
    • C11D7/04—Water-soluble compounds
    • C11D7/06—Hydroxides
    • C—CHEMISTRY; METALLURGY
    • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
    • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
    • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
    • C11D7/02—Inorganic compounds
    • C11D7/04—Water-soluble compounds
    • C11D7/10—Salts
    • C11D7/12—Carbonates bicarbonates

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Wood Science & Technology (AREA)
  • Organic Chemistry (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)

Abstract

The present invention provides a membrane cleaning liquid which can be used in a chemical mechanical polishing process to regenerate a membrane to be discarded, and a membrane regeneration method using the same.
The membrane cleaning solution according to the present invention comprises potassium hydroxide (KOH); Hydrogen peroxide (H 2 O 2 ); Water (H 2 O); And sodium carbonate (Na 2 CO 3 ), wherein the membrane cleaning liquid comprises potassium hydroxide (KOH): 5 to 40 wt%; 5 to 30% by weight of hydrogen peroxide (H 2 O 2 ); 3 to 20% by weight of sodium carbonate (Na 2 CO 3 ); And 52 to 83% by weight of water (H 2 O).

Description

TECHNICAL FIELD [0001] The present invention relates to a membrane cleaning liquid and a membrane regeneration method using the same. BACKGROUND ART [0002] MEMBRANE CLEANER AND METHOD FOR RECYCLING MEMBRANE USING THE SAME [0003]

The present invention relates to a membrane cleaning solution and a membrane regeneration method using the same. More particularly, the present invention relates to a membrane cleaning solution for regenerating and reusing a membrane, and a membrane regeneration method using the same.

CMP (Chemical Mechanical Polishing) process is a chemical mechanical polishing process that polishes the surface of a wafer flatly using chemical reaction and mechanical force during semiconductor manufacturing. The surface of the wafer is polished using a polishing pad and a slurry solution Mechanical and chemical polishing.

1 shows a conventional chemical mechanical polishing apparatus comprising a rotatable platen 10, a polishing pad 20 attached on the platen 10 and a head 30 disposed on top of the polishing pad 20, . The head 30 is rotatably connected to the driving unit by a rotary shaft 31,

In the lower portion of the head 30, there is provided a support plate on which a plurality of through holes are formed, and a retainer ring 40 surrounding the support body is coupled to the lower portion of the head 30. [ The retainer ring 40 has an annular shape so as to surround the wafer, so as to prevent the wafer from separating from the head 30 during the polishing process.

A membrane is mounted on the support plate inside the retainer ring 40, and a wafer for processing is placed in contact with the membrane. The membrane is made of an elastic soft material, and concentric bulkheads are generally formed on the backside of the membrane so that a negative pressure or a positive pressure of air can be applied to the wafer side.

The membrane may be made of various materials, but is generally made of a material having good stretchability such as silicone rubber, neoprene rubber, and ethylene propylene rubber, and has a thickness of about 0.5 mm to about 1.5 mm to be.

The wafer polishing process is as follows. First, a negative pressure is applied to the membrane side through a through-hole to adsorb and fix the wafer on the membrane. The head 30 facing the polishing pad 20 is moved toward the polishing pad 20 to bring the wafer into contact with the polishing pad 20 and then the polishing pad 20 and the head The surface of the wafer is processed by friction between the polishing pad 20 and the wafer. At this time, it is possible to pressurize the wafer by air pressure by applying a static pressure to the membrane side through the through holes, and to adjust the polishing rate by controlling the degree of pressurization.

The surface tackiness of the membrane, which is directly contacted with and supported by the wafer, affects the processing of the wafer, and surface treatment for improving surface characteristics is considered important.

Particularly, a method for improving the slip property and adhesiveness of the membrane surface has been studied, and there is a method of surface treatment during membrane molding and a method of coating treatment with chemicals after the membrane is manufactured.

Among them, the coating treatment method is to increase the slip and tackiness by roughening the membrane coated surface, and there are a spraying method in which the coating liquid is sprayed on the surface of the membrane and an immersion method in which the membrane is immersed in the coating liquid.

When the membrane is used for a predetermined period of time, the surface is contaminated by slurry or residues generated during processing, and the surface coating layer is damaged, resulting in poor processing characteristics. Therefore, the polishing process must be carried out by replacing with a new membrane, and the membrane used is discarded. However, since the price of the membrane is high and the replacement cycle of the membrane is not long, the purchase cost of the consumed membrane is high, which is economically disadvantageous .

Therefore, it is expected to be economically advantageous if it is possible to regenerate the discarded membrane, but there is no known means or method for regenerating the membrane.

An object of the present invention is to provide a membrane regeneration method capable of regenerating a damaged membrane.

It is another object of the present invention to provide a membrane regeneration method capable of reliable cleaning during regeneration and facilitating coating operation.

The membrane cleaning solution according to the present invention comprises potassium hydroxide (KOH); Hydrogen peroxide (H 2 O 2 ); Water (H 2 O); And sodium carbonate (Na 2 CO 3 ), wherein the membrane cleaning liquid comprises potassium hydroxide (KOH): 5 to 40 wt%; 5 to 30% by weight of hydrogen peroxide (H 2 O 2 ); 3 to 20% by weight of sodium carbonate (Na 2 CO 3 ); And 52 to 83% by weight of water (H 2 O).

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Preferably, a membrane regeneration method using a membrane cleaning liquid comprises: a cleaning step of cleaning the surface of a membrane used with the membrane cleaning liquid; And a drying step of drying the membrane.

Preferably, the rinsing step may further include a rubbing step of alcohol-treating the membrane surface after the cleaning step.

Preferably, the coating step of coating the surface of the membrane after the drying step; And a coating drying step of drying the coated membrane.

Preferably, in the coating step, the coating liquid may be selectively applied to the coating layer damage portion of the membrane surface.

Preferably, the coating liquid can be applied by being stamped on a sponge.

Preferably, the coating liquid may be applied by spraying.

Preferably, the final cleaning step for cleaning the membrane after the coating drying step is performed; And a final drying step of drying the membrane after the final cleaning step.

Preferably, it can be cleaned with water in the final cleaning step.

According to the membrane regeneration method of the present invention, the membrane can be reused by regenerating the used membrane, thereby reducing the cost of purchasing the membrane. In addition, it is possible to reliably clean during the regeneration treatment, to facilitate the coating operation, and to reduce the cost of the coating liquid.

1 is a view showing a conventional chemical mechanical polishing apparatus,
2 is a flow chart for a cleaning process of a membrane regeneration method according to an embodiment of the present invention,
3 is a flow chart for a coating process of a membrane regeneration method according to an embodiment of the present invention, and
4 is a flowchart of a final cleaning process of the membrane regeneration method according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Accordingly, it is to be understood that the constituent features of the embodiments described herein are merely the most preferred embodiments of the present invention, and are not intended to represent all of the inventive concepts of the present invention, so that various equivalents, And the like.

2 is a flowchart of a cleaning process of a membrane regeneration method according to an embodiment of the present invention.

The cleaning process of the membrane regeneration method according to an embodiment of the present invention may include an import inspection step S101, a cleaning step S102, a rubbing step S103, a drying step S104, and an inspection step S105 .

The import inspection step (S101) can be done visually and can be used to polish the wafer and then permanently damaged to separate non-renewable membranes.

In the cleaning step S102, the membrane may be cleaned with a cleaning liquid, wherein the membrane cleaning liquid according to an embodiment of the present invention comprises potassium hydroxide (KOH), hydrogen peroxide (H 2 O 2 ), sodium carbonate (Na 2 CO 3 ) (H 2 O) at a predetermined ratio.

The cleaning liquid according to one embodiment of the present invention is formed in the following ratio.

- 5 to 40% by weight of potassium hydroxide (KOH)

- 5 to 30% by weight of hydrogen peroxide (H 2 O 2 )

- 3 to 20% by weight of sodium carbonate (Na 2 CO 3 )

52 to 83% by weight of water (H 2 O)

Potassium hydroxide weakens the electrostatic force of the membrane surface so that contaminants can be removed from the membrane surface, and metal contaminants can be effectively removed, especially. In addition, when basic potassium hydroxide is used, there is an advantage that the membrane made of a silicone rubber material can be prevented from being damaged.

Hydrogen peroxide acts as a catalyst to improve the removal rate of contaminants and can increase the reaction temperature. According to one embodiment of the present invention, when potassium hydroxide and water are mixed, the reaction temperature is about 70 ° C. However, when hydrogen peroxide is mixed, the pollutant removal rate can be improved by heating to about 110 to 120 ° C .

Sodium carbonate acts as a surfactant and acts as an emulsifier to allow easy mixing of potassium hydroxide and hydrogen peroxide. Further, it is preferable that water is ultrapure water that minimizes impurities.

At this time, the pH of the washing liquid is preferably 11 to 14, and in the case of acid, the membrane may be damaged or the surface may be discolored.

If potassium hydroxide is less than 5 wt%, there is a problem that contaminants on the surface of the membrane are not sufficiently removed. If it exceeds 40 wt%, the membrane is etched and damaged.

When the amount of hydrogen peroxide is less than 5% by weight, the reactivity is poor and the catalytic action does not sufficiently take place. Therefore, there is a problem that the contaminant removal rate is lowered and the contaminants are not removed sufficiently. When the hydrogen peroxide is more than 30% by weight, There is a problem that it is changed and damaged by etching.

When sodium carbonate is less than 3% by weight, it does not act as an emulsifier. Thus, potassium hydroxide and hydrogen peroxide are not easily mixed to cause unevenness. When the amount is more than 20% by weight, detergency is deteriorated. In the case where potassium hydroxide and hydrogen peroxide are not easily mixed, the washing liquid in the immersion tank is not uniform and the degree of washing of the membrane may be changed depending on the position in the immersion tank.

In the cleaning step, the surface of the membrane is cleaned using the cleaning liquid thus prepared to remove contaminants. According to an embodiment of the present invention, the membrane may be immersed in the cleaning liquid of the immersion tank to be cleaned. However, the present invention is not limited thereto, And the cleaning liquid can be supplied and cleaned by various methods such as immersing in the flowing cleaning liquid.

In the rubbing step (S103) after the washing step, the alcohol remaining on the surface of the membrane can be removed by alcohol (C 2 H 5 OH), which is a process for facilitating the subsequent coating process. A coating failure may occur.

In the drying step (S104), the ethanol-treated membrane may be dried. According to an embodiment of the present invention, the drying may be natural drying at room temperature, but the present invention is not limited thereto. For example, Can be dried by various methods.

The membrane subjected to the drying step can be inspected in the inspection step (S105), and this can be done by visual inspection or SEM-EDS analysis.

3 is a flowchart of a coating process of the membrane regeneration method according to an embodiment of the present invention.

The coating process of the membrane regeneration method according to an embodiment of the present invention includes a coating step (S201), a coating drying step (S202), and a coating inspection step (S203).

In the coating step (S201), the surface of the membrane after the cleaning process can be coated.

The coating layer on the surface of the membrane used for wafer polishing is partially thinned or removed due to the friction with the wafer, thereby exposing the membrane base material. In the coating step, only the damaged portion of the coating layer can be selectively coated.

According to an embodiment of the present invention, a silicone solution may be used as a coating material, and a silicon solution may be partially coated on a surface of the membrane where a coating layer is damaged by using a sponge or the like. Therefore, the coating material can be saved, and the cost thereof can also be reduced.

According to another embodiment of the present invention, the coating layer may be coated so as to fill a locally damaged coating layer by spraying a silicon solution onto a damaged area.

After the coating step, the coated membrane may be dried in the coating drying step (S202). According to one embodiment of the present invention, it may be naturally dried at room temperature and dried for 3 to 4 days. However, it is not limited to this, and it can be dried by various methods such as exposure to a high temperature atmosphere or forced air supply.

The coated state of the membrane can be inspected in the coating inspection step (S203), which can be done by visual inspection or SEM-EDS analysis.

4 is a flowchart of a final cleaning process of the membrane regeneration method according to an embodiment of the present invention.

The final cleaning step of the membrane regeneration method according to an embodiment of the present invention includes a final cleaning step S301, a final drying step S302, a final inspection step S303, and a packaging step S304.

There at the last washing step (S301) the membrane can be cleaned by a final rinse solution, the final rinse solution may be water (H 2 O), in particular ultra-pure water. In the final cleaning step, the surface of the membrane is cleaned using the final cleaning liquid thus prepared to remove contaminants.

The final dried membrane may be dried in the final drying step (S302). According to one embodiment of the present invention, the membrane may be naturally dried at room temperature, but the present invention is not limited thereto. The membrane may be exposed to a high temperature atmosphere or forcedly supplied with dry air And the like.

In the final drying step, the membrane may be inspected for residual contaminants in the final inspection step (S303), which may be done by visual inspection or SEM-EDS analysis.

Finally, the finished membrane may be packaged in the packaging step S304, and may be packaged by vacuum packaging according to one embodiment of the present invention.

Hereinafter, the cleaning liquid of the present invention will be described in detail through examples.

Example 1

The cleaning solution containing 20% by weight of potassium hydroxide, 15% by weight of hydrogen peroxide and 2% by weight to 22% by weight of sodium carbonate was mixed in a mixer for 3 minutes, and the membrane was immersed in a cleaning solution for 3 minutes. EDS analysis.

Potassium hydroxide Hydrogen peroxide Sodium carbonate water Degree of cleaning Degree of damage Cleaning solution 1

20



15

2 63 Bad Good Cleaning solution 2 4 61 Good Good Cleaning solution 3 10 55 Good Good Cleaning solution 4 18 47 Good Good Cleaning solution 5 22 43 Bad damaged

When the sodium carbonate was less than 3 wt%, and when it was more than 20 wt%, the detergency was poor and the membrane surface was damaged. Therefore, according to one embodiment of the present invention, it is preferable that sodium carbonate is 3 wt% to 20 wt%.

Example 2

A cleaning solution containing 20% by weight of potassium hydroxide, 3 to 32% by weight of hydrogen peroxide and 10% by weight of sodium carbonate was mixed with water in a mixer for 3 minutes, and the membrane was immersed in the cleaning solution for 3 minutes. EDS analysis.

Potassium hydroxide Hydrogen peroxide Sodium carbonate water Degree of cleaning Degree of damage Cleaning solution 6

20

3

10

67 Bad Good Cleaning solution 7 7 63 Good Good Cleaning solution 8 15 55 Good Good Cleaning solution 9 28 45 Good Good Cleaning solution 10 32 38 Good damaged

When the hydrogen peroxide was less than 5 wt%, the detergency was poor, and when the hydrogen peroxide was more than 30 wt%, the membrane surface was damaged. Therefore, according to one embodiment of the present invention, it is preferable that hydrogen peroxide is 5 wt% to 30 wt%.

Example 3

The cleaning solution containing 4 wt% to 42 wt% of potassium hydroxide, 15 wt% of hydrogen peroxide, and 10 wt% of sodium carbonate was mixed with water for 3 minutes in a mixer, and the membrane was immersed in a cleaning solution for 3 minutes. EDS analysis.

Potassium hydroxide Hydrogen peroxide Sodium carbonate water Degree of cleaning Degree of damage Cleaning solution 11 4

15



10

71 Bad Good Cleaning solution 12 6 69 Good Good Cleaning solution 13 20 55 Good Good Cleaning liquid 14 38 40 Good Good Cleaning solution 15 42 33 Good damaged

When the potassium hydroxide content is less than 5% by weight, the detergency is poor, and when it exceeds 40% by weight, the membrane surface is damaged. Therefore, according to one embodiment of the present invention, it is preferable that potassium hydroxide is 5 wt% to 40 wt%.

When the membrane is used for a predetermined period of time, the surface is contaminated by slurry or residues generated during processing, and the surface coating layer is damaged, resulting in poor processing characteristics. Therefore, the polishing process must be carried out by replacing with a new membrane, and the used membrane is discarded.

However, since the price of the membrane is high and the replacement cycle of the membrane is not long, the purchase cost of the consumed membrane is high, which is economically disadvantageous.

However, according to the present invention, it is possible to reuse the membrane by regenerating the used membrane, thereby reducing the cost of purchasing the membrane. In addition, it is possible to reliably clean during the regeneration treatment, to facilitate the coating operation, and to reduce the cost of the coating liquid.

While the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, Various modifications and variations are possible within the scope of the appended claims.

S101: Import Inspection Step S102: Cleaning Step
S103: Main coupling part S104: Sub coupling part
S105:
S201: coating step S202: coating drying step
S203: Coating inspection step
S301: Final cleaning step S302: Final drying step
S303: Final inspection step S304: Packaging step

Claims (11)

Potassium hydroxide (KOH);
Hydrogen peroxide (H 2 O 2 );
Water (H 2 O); And
As a membrane cleaning liquid containing sodium carbonate (Na 2 CO 3 )
The membrane cleaning liquid,
Potassium hydroxide (KOH): 5 to 40% by weight; 5 to 30% by weight of hydrogen peroxide (H 2 O 2 ); 3 to 20% by weight of sodium carbonate (Na 2 CO 3 ); And water (H 2 O): 52 to 83% by weight.
delete delete A membrane regeneration method using the membrane cleaning liquid of claim 1,
A cleaning step of cleaning the surface of the membrane used with the membrane cleaning liquid; And
A drying step of drying the membrane
. ≪ / RTI >
5. The method of claim 4,
A rubbing step of subjecting the membrane surface to an alcohol treatment after the washing step
Further comprising the steps of:
6. The method of claim 5,
A coating step of coating the surface of the membrane after the drying step; And
A coating drying step of drying the coated membrane
Further comprising the steps of:
The method according to claim 6,
Wherein the coating liquid is selectively applied to a damaged portion of the coating layer on the surface of the membrane in the coating step.
8. The method of claim 7,
Wherein the coating liquid is applied on a sponge.
8. The method of claim 7,
Wherein the coating liquid is applied by spraying.
The method according to claim 6,
A final cleaning step for cleaning the membrane after the coating drying step; And
A final drying step of drying the membrane after the final cleaning step
Further comprising the steps of:
11. The method of claim 10,
Wherein the membrane can be cleaned with water in the final cleaning step.
KR1020150175830A 2015-12-10 2015-12-10 Membrane cleaner and method for recycling membrane using the same KR101799061B1 (en)

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KR101799061B1 true KR101799061B1 (en) 2017-12-20

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013158743A (en) 2012-02-08 2013-08-19 Adeka Corp Method for washing separation membrane
WO2015166826A1 (en) * 2014-05-02 2015-11-05 三菱瓦斯化学株式会社 Semiconductor element cleaning liquid and cleaning method

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013158743A (en) 2012-02-08 2013-08-19 Adeka Corp Method for washing separation membrane
WO2015166826A1 (en) * 2014-05-02 2015-11-05 三菱瓦斯化学株式会社 Semiconductor element cleaning liquid and cleaning method

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