KR102265414B1 - Cleansing composition for metal film - Google Patents

Abstract

The present invention relates to a cleaning composition for a metal film, and more particularly, to a cleaning composition for removing residues and impurities remaining on a metal film during a flat panel display manufacturing process.

Description

Cleaning composition for metal film {CLEANSING COMPOSITION FOR METAL FILM}

The present invention relates to a cleaning composition for a metal film, and more particularly, to a cleaning composition for removing residues, impurities, contaminants, etc. remaining on a metal substrate after various processing processes in a flat panel display manufacturing process.

BACKGROUND ART A flat panel display device, like a semiconductor device, is manufactured through processes such as film formation, exposure, and etching. However, during such a manufacturing process, contamination by adhesion of various organic or inorganic substances to the surface of the substrate occurs, and there is a problem in that residues are left. or these contaminants. When the following process treatment is performed in a state where residues, etc. remain, pinholes or pits in the film, disconnection of wiring or bridges occur, and the production yield of the product decreases.

Therefore, cleaning to remove contaminants is performed between each process, and there have been many studies on cleaning agents for this purpose.

In relation to this, Korean Patent Laid-Open No. 2004-0035368 discloses a cleaning composition for semiconductors and TFT-LCDs composed of an alkanol amine, an organic solvent, a chelate compound, and water. However, the cleaning agent lacks the ability to remove organic contaminants and particles, and may cause precipitation problems when used for a long period of time due to polyhydroxybenzene-based chelate compounds such as catechol or gallic acid. Korean Patent Laid-Open No. 2006-0127098 discloses a cleaning agent for a substrate for a semiconductor device comprising an organic acid, an organic alkali, a surfactant, and water.

However, since the detergent of the disclosed patent is a solution in an acidic range, there is a disadvantage that a residue may remain during the rinsing process and the particle removal power is insufficient. In addition, there is a disadvantage that the corrosion prevention ability of the metal film is not excellent.

Republic of Korea Patent Publication 2004-0035368 Republic of Korea Patent Publication 2006-0127098

The present invention has been devised to solve the problems of the prior art, and by providing a cleaning composition for a metal film containing a basic corrosion inhibitor, it does not cause damage to the metal film in the process of removing residues and impurities, and excellent removal ability of residues and impurities At the same time, an object of the present invention is to provide a cleaning composition for a metal film that does not leave a corrosion inhibitor residue in the rinse process.

The present invention is

(A) at least one selected from alkali metal hydroxide and alkylammonium hydroxide, (B) a polar solvent capable of dissolving at least 1 part by weight per 100 parts by weight of the hydroxide, and (C) basic corrosion It provides a cleaning composition for a metal film, characterized in that it contains an inhibitor.

The basic corrosion inhibitor may preferably be an amine group-containing pyridine.

Since the cleaning composition for a metal film of the present invention includes a basic corrosion inhibitor, it is possible to prevent corrosion of the metal during cleaning, as well as provide an effect that no residue is left after the rinse process with pure water.

1 is a scanning electron microscope (SEM) photograph showing the corrosion state of the surface of the metal film that occurs during cleaning,
1 (A) is a state in which corrosion does not occur after cleaning, (B) is a state in which a small amount of metal oxide is produced by slight oxidation, (C) is a state in which a large amount of metal oxide is produced by a significant amount of oxidation , (D) is a photograph of a state in which a large amount of metal oxide is generated and then etched away and the surface is very rough.

Hereinafter, the present invention will be described in more detail.

The present invention is

In the flat panel display manufacturing process, metals such as metal films that may be exposed to the cleaning composition are not corroded to any undesirable degree, and residues such as, but not limited to, residues after plasma etching, residues after plasma exfoliation, etc. are removed from the substrate Disclosed is a cleaning composition for a metal film that does not leave a corrosion inhibitor residue after rinsing.

That is, it relates to a cleaning composition for a metal film that prevents corrosion of the metal film after a process such as etching and excellently removes residues and impurities remaining on the film quality,

(A) at least one hydroxide selected from alkali metal hydroxide and alkylammonium hydroxide, (B) a polar solvent capable of dissolving at least 1 part by weight per 100 parts by weight of the hydroxide, and (C ) It relates to a cleaning composition for a metal film, characterized in that it contains a basic corrosion inhibitor.

The cleaning composition of the present invention not only has corrosion resistance to the metal film during cleaning, but also easily removes residues and impurities such as resist, organic insulating film, and transparent resin by the composition as described above, and the residue in the rinsing process is removed. It can provide a lasting effect.

Hereinafter, each component is demonstrated concretely.

(A) hydroxide compound

The hydroxide compound of the present invention discharges hydroxide ions, which penetrate into residues such as resists and serve to promote dissolution of polymer resists and the like. In addition, it has a cleaning action on organic and inorganic contaminants, and improves the cleaning effect by preventing re-adsorption of particles after cleaning.

The hydroxide compound may be at least one selected from the group consisting of alkali metal hydroxides and alkylammonium hydroxides.

The alkali metal hydroxide may include, for example, LiOH, NaOH, KOH, RbOH and CsOH, and these may be used alone or in combination of two or more, but is not limited thereto.

The alkylammonium hydroxide is, for example, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH) and tetrabutylammonium hydroxide (TBAH). It may be one or more selected from the group consisting of, but is not limited thereto.

The hydroxide compound of the present invention is preferably included in an amount of 0.1 to 5% by weight, more preferably 0.3 to 1% by weight, based on the total weight of the cleaning composition. When the hydroxide compound is included in an amount of less than 0.1% by weight in the cleaning composition of the present invention, the penetration power of hydroxide ions in the resist polymer is reduced, the solubility in resist is reduced, and when it exceeds 5% by weight, corrosion of the metal occurs. And, there is a problem in that the content of water is increased, so that the dissolving power for the polymer resin and the like is reduced.

However, the detergent composition of the present invention preferably has the above content ratio when used as a detergent, but in consideration of the ease of transport and storage, it is prepared and transported by including 10 to 30% by weight of the hydroxide compound with respect to the total weight of the detergent composition And it is preferable to store and dilute to the above composition when used.

(B) Polar solvent

The polar solvent (B) of the present invention penetrates the resist and increases the swelling property, thereby increasing the peeling force of residues from the surface of the substrate. In addition, it improves the solubility in water of the cleaning composition of the present invention, and facilitates the removal of residues and the cleaning composition in the subsequent water washing process.

The polar solvent is characterized in that it can dissolve 1 part by weight or more per 100 parts by weight of the hydroxide compound. This is necessary in order to suppress the occurrence of precipitates of the hydroxide compound due to aging during production and storage. In addition, when washing is performed under heating conditions in the washing process, it is necessary to suppress the occurrence of precipitates due to an increase in the concentration of the hydroxide compound due to volatilization of the solvent.

The polar solvent may include a protic polar solvent and an aprotic polar solvent, which may be used alone or in combination. Preferred examples of the protic polar solvent include water (deionized water), alkyl alcohols, glycols, and the like, and examples of the alkyl alcohols include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butanol, pentanol, hexanol, heptanol and octanol;

Examples of glycols include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono Isopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monoisopropyl ether, triethylene glycol monobutyl ether, polyethylene glycol monomethyl ether, polyethylene glycol monobutyl and alkylene glycol monoalkyl ethers such as ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, and tripropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, and tetrahydrofurfuryl alcohol. The species may be used alone or two or more species may be used together.

Preferred examples of the aprotic polar solvent include pyrrolidone compounds such as N-methylpyrrolidone (NMP) and N-ethylpyrrolidone; imidazolidinone compounds such as 1,3-dimethyl-2-imidazolidinone and 1,3-dipropyl-2-imidazolidinone; lactone compounds such as γ-butyrolactone; sulfoxide compounds such as dimethyl sulfoxide (DMSO), diethyl sulfoxide, dipropyl sulfoxide and sulfolane; phosphate compounds such as triethyl phosphate and tributyl phosphate; carbonate compounds such as dimethyl carbonate and ethylene carbonato; Formamide, N-methylformamide, N,N-dimethylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-(2-hydroxyethyl)acetamide, 3-methoxy and amide compounds such as -N,N-dimethylpropionamide, 3-(2-ethylhexyloxy)-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide. It may be used alone or in combination of two or more, but is not limited thereto.

Among the solvents, water may be preferably used as the protic polar solvent, and DMSO may be preferably used as the aprotic polar solvent.

The polar solvent of the present invention is preferably included in an amount of 70% by weight or more based on the total weight of the detergent composition, and in consideration of the solubility of the hydroxide compound, 50% by weight or more of the protic polar solvent is contained with respect to 100% by weight of the polar solvent. It is preferable to do

The aprotic polar solvent is preferably included in an amount of 0 to 45% by weight, more preferably 10 to 30% by weight, based on the total weight of the cleaning composition.

The content of the aprotic polar solvent that can be included in the cleaning composition of the present invention can be adjusted according to the type of object to be cleaned, and it is not necessary to add the aprotic polar solvent for the purpose of simply removing foreign substances. However, when the purpose of removing polymers such as photoresists is to use 10 wt% or more of an aprotic polar solvent based on the total weight of the cleaning composition, it may be more suitable for swelling of the cross-linked polymer and dissolving the removed polymer. have.

However, if the content of the aprotic polar solvent exceeds 45% by weight based on the total weight of the detergent composition, the activity of the hydroxide compound is inhibited, and there is a concern about the occurrence of precipitates due to the decrease in solubility, the price increases, and there is a risk of odor there is

(C) corrosion inhibitor

The cleaning composition for metal films of this invention contains a corrosion inhibitor (C). The corrosion inhibitor is included in the cleaning composition to improve the corrosion preventing ability of the metal film including aluminum and / or copper. In particular, it has excellent solubility in water and polar solvents, so it does not remain on the surface of the substrate.

The basic corrosion inhibitor is preferably an amine group-containing pyridine. In the amine group-containing pyridine, a nitrogen atom in the pyridine is cationized during the rinse process with pure water. Therefore, it has excellent solubility in water and polar solvents and does not remain on the surface of the metal film. That is, since the metal film and the chelating corrosion inhibitor are cationized, the bonding force with the metal film is weakened, and solubility in water and polar solvents is increased, so that it is easily cleaned without leaving any residue on the substrate, the metal film, etc. can be

If the corrosion inhibitor remains on the surface of the substrate or the metal film, it may cause a decrease in adhesion to the layer positioned on the substrate in a subsequent process. Therefore, the corrosion inhibitor of the present invention can provide an effect of increasing the precision of the subsequent process by not leaving a residue after rinsing.

The corrosion inhibitor is more preferably at least one selected from the compound represented by the following formula (1).

[Formula 1]

In Formula 1,

R1 and R2 are each hydrogen, a C1-C4 aliphatic hydrocarbon,

R3 may be at least one selected from hydrogen, C1-C4 aliphatic hydrocarbons, a hydroxyl group, an alkoxy group, a carboxylic acid group, an amine group, and a halogen.

Examples of the corrosion inhibitor of Formula 1 may include, but are not limited to, Formulas 2 to 8, and the like.

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

[Formula 7]

[Formula 8]

These can be used individually or in mixture of 2 or more types.

The corrosion inhibitor is preferably included in an amount of 3% by weight or less, and more preferably in an amount of 0.001 to 1% by weight, based on the total weight of the cleaning composition for a metal film. When included in the above range, it is possible to prevent corrosion occurring in the metal film made of aluminum or aluminum alloy and copper or copper alloy, etc. in the cleaning or DI rinse process, and secondary contamination due to adsorption of the metal film surface and A decrease in peel strength can be prevented.

The cleaning composition for a metal film of the present invention may further include one or more of the group consisting of an oxygen scavenger and a surfactant as other additives (D).

In the present invention, the oxygen scavenger is additionally included in the cleaning composition to help prevent corrosion of the metal, and an example may include, but is not limited to, ethanolamine. It may be preferable that the oxygen scavenger is included in an amount of 1% by weight or less based on the total weight of the cleaning composition.

In the present invention, the surfactant is further included in the cleaning composition to improve the wettability to the surface to be cleaned, and serves to improve the cleaning property. Examples include, but are not limited to, tetraethylene glycol dimethyl ether. It may be preferable that the surfactant is included in an amount of 1% by weight or less based on the total weight of the cleaning composition.

Hereinafter, the present invention will be described in more detail through Examples and Comparative Examples. However, the following examples are provided to explain the present invention in more detail, and the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

Example and comparative example : Preparation of cleaning composition

The cleaning compositions of Examples 1 to 7 and Comparative Examples 1 to 3 were prepared by mixing the components shown in Table 1 according to a predetermined composition ratio.

(A) Hydroxide compound (B) Polar solvent (C) corrosion inhibitor (D) other additives Kinds weight% aprotic
Polar solvent Quantum
Polar solvent Kinds weight% Kinds weight% Kinds weight% deionized water Example 1 TMAH 0.4 DMSO 30 remaining amount Formula 3 0.2 - - Example 2 TMAH 0.4 DMSO 30 remaining amount Formula 3 0.05 - - Example 3 TMAH 0.4 DMSO 30 remaining amount Formula 3 0.01 - - Example 4 TMAH 0.4 DMSO 30 remaining amount Formula 4 0.2 - - Example 5 TMAH 0.4 DMSO 30 remaining amount Formula 5 0.2 Example 6 TEAH 0.5 DMSO 30 remaining amount Formula 3 0.2 ethanolamine 0.3 Example 7 TMAH 0.4 DMSO 30 remaining amount Formula 9 0.2 tetraethylene glycol
dimethyl ether 0.5 Comparative Example 1 TMAH 0.4 DMSO 30 remaining amount - - - - Comparative Example 2 TMAH 0.4 DMSO 30 remaining amount BTA 0.2 - - Comparative Example 3 TMAH 0.4 DMSO 30 remaining amount ATZ 0.2 - -

week)

(B) Polar solvent

DMSO: dimethyl sulfoxide

(C) corrosion inhibitor

[Formula 9]:

BTA: benzotriazole

ATZ: aminotetrazole

(D) other additives

Oxygen (O ₂ ) scavenger: ethanolamine

Nonionic surfactant: tetraethylene glycol dimethyl ether

< Experimental example >

Experimental example 1: of the cleaning composition residue and contaminants detergency evaluation

(One)

The cleaning properties of residues and contaminants of the cleaning compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 3 were evaluated.

Example 1 in which a substrate contaminated with silicon oil, Al and SUS (Stainless Steel) powder was maintained at a temperature of 50° C. on a wafer having a Cu layer according to a conventional method in order to confirm the cleaning property of the cleaning composition for a metal film. It was immersed in the detergent compositions of ~7 and Comparative Examples 1-3 for 5 minutes. Thereafter, cleaning was performed for 1 minute with pure water to remove the cleaning agent composition remaining on the substrate, and then the substrate was completely dried using nitrogen to remove the pure water remaining on the substrate after cleaning.

Thereafter, the cleaning degree of residues and contaminants was confirmed using a scanning electron microscope (SEM, Hitach S-4700), and the results are shown in Table 2 below.

[Evaluation of cleaning properties of residues and contaminants]

◎: 100% removal of residues and contaminants

○: Removal of more than 80% of residues and contaminants

△: Removal of less than 80% of residues and contaminants

×: Residues and contaminants not removed

(2)

Based on the fact that the higher the pH of the detergent composition, the better the cleaning properties of residues and impurities, and 0.4 wt% of TMAH as a hydroxide, 30 wt% of DMSO as a solvent, the residual amount of deionized water, and Examples 1 of Table 1 7 and Comparative Examples 1 to 3 and each of the same type of corrosion inhibitor 0.1% by weight of the prepared detergent composition to measure the pH change, the results are shown in Table 2 below.

[Evaluation of pH change]

(circle): pH is improved by the addition of an additive.

△: No change in pH due to the addition of additives

x: pH becomes low by addition of an additive.

Experimental example 2: metal film corrosion prevention evaluation

In order to evaluate the corrosion resistance of the metal film of the cleaning composition prepared in Examples 1 to 7 and Comparative Examples 1 to 3, a glass substrate formed to a thickness of 2500 Å of copper using a thin film sputtering method on a glass substrate according to a conventional method was prepared. prepared. The temperature of the cleaning composition prepared in Examples 1 to 7 and Comparative Examples 1 to 3 was maintained at 40° C., and the copper-formed glass substrate was immersed for 30 minutes to wash. After rinsing for 30 seconds using DIW (deionized water), the cleaning composition, DIW, etc. remaining on the substrate were completely removed using nitrogen.

The degree of surface oxidation of the substrate was confirmed using a scanning electron microscope (SEM, Hitach S-4700), and the results are shown in Table 2 and FIG. 1 below.

[Corrosion prevention evaluation criteria]

◎: No corrosion

○: slight corrosion

△: Severe corrosion

×: Etching occurs after corrosion

Experimental example 3: contact angle evaluation

In order to evaluate the contact angle change according to the residual corrosion inhibitor of the cleaning compositions prepared in Examples 1 to 7 and Comparative Examples 1 to 3, a contact angle evaluation experiment was conducted.

According to a conventional method, a glass substrate formed to a thickness of 2500 Å of copper was prepared on a glass substrate by thin film sputtering. After leaving the substrate in the air for 24 hours to contaminate various organic, inorganic, and particles in the air, using a spray-type cleaning device at 40° C. for 2 minutes with the cleaning composition of Examples 1 to 7 and Comparative Examples 1 to 3 washed. After washing, it was washed with ultrapure water for 30 seconds and then dried with nitrogen. A drop of 0.5 μl of ultrapure water was dropped on the substrate to measure the contact angle after cleaning, and the results are shown in Table 2 below.

[Contact angle evaluation criteria]

○: The contact angle is lower than the copper surface before cleaning. (Decreased contact angle due to increase in roughness of copper surface due to cleaning)

x: The contact angle is high compared to the copper surface before washing|cleaning. (Increased contact angle due to surface residual of corrosion inhibitor)

detergency corrosion protection Contact angle evaluation residues and contaminants
detergency change in pH Cu Example 1 ◎ ○ ○ ○ Example 2 ◎ ○ ○ ○ Example 3 ◎ ○ ○ ○ Example 4 ◎ ○ ○ ○ Example 5 ◎ ○ ○ ○ Example 6 ◎ ○ ○ ○ Example 7 ◎ ○ ○ ○ Comparative Example 1 ◎ △ × ○ Comparative Example 2 ○ × ◎ × Comparative Example 3 ○ × ○ ×

As shown in Table 2, it was confirmed that the cleaning compositions of Examples 1 to 7 exert a very excellent cleaning effect in removing residues. In addition, it was confirmed that corrosion did not occur in the evaluation of corrosion prevention properties of the metal film, and thus had excellent metal corrosion prevention properties. In addition, in the evaluation of the contact angle, it was confirmed that the corrosion inhibitor did not remain, as the contact angle was lower than the copper surface before cleaning.

On the other hand, since the composition of Comparative Examples 1 to 3 showed no increase or decrease in pH after the addition of the additive, it could be inferred that the cleaning properties were low, and showed poor results in the evaluation of residue cleaning properties. In addition, it was not possible to prevent serious corrosion from occurring in the corrosion protection evaluation, and it was confirmed that the corrosion inhibitor remained on the metal surface, as the contact angle was increased compared to the copper surface before cleaning.

Claims (6)

(A) at least one hydroxide selected from alkali metal hydroxide and alkylammonium hydroxide, (B) a polar solvent capable of dissolving at least 1 part by weight per 100 parts by weight of the hydroxide, and (C ) contains a basic corrosion inhibitor,
The polar solvent includes a protic polar solvent and an aprotic polar solvent,
The basic corrosion inhibitor is a cleaning composition for a metal film, characterized in that the amine group-containing pyridine.
delete The method according to claim 1,
The amine group-containing pyridine is a cleaning composition for a metal film, characterized in that the formula (1).
[Formula 1]

In Formula 1,
R1 and R2 are each hydrogen or a C1-C4 aliphatic hydrocarbon;
R3 may be at least one selected from hydrogen, C1-C4 aliphatic hydrocarbons, a hydroxyl group, an alkoxy group, a carboxylic acid group, an amine group, and a halogen.
The method according to claim 1,
0.1 to 5% by weight of hydroxide based on the total weight of the detergent composition;
70% by weight or more of a polar solvent; and
A cleaning composition for a metal film comprising 3 wt% or less of a corrosion inhibitor.
The method according to claim 1,
The alkali metal hydroxide is at least one selected from the group consisting of LiOH, NaOH, KOH, RbOH and CsOH;
The alkylammonium hydroxide is from the group consisting of tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH) and tetrabutylammonium hydroxide (TBAH). A cleaning composition for a metal film, characterized in that at least one selected.
The method according to claim 1,
A cleaning composition for a metal film further comprising at least one selected from the group consisting of oxygen scavengers and surfactants.

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