JP2014063186A - Photoresist stripper composition for manufacturing lcd comprising primary alkanolamine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous photoresist stripper which uses as a corrosion inhibitor an azole compound including a mercapto group, which is a stripper composition additive for a TFT-LCD, to maintain constant corrosion inhibiting and photoresist stripping capabilities for Cu and Al even when water content varies.SOLUTION: The photoresist stripper composition for manufacturing an LCD includes: (a) 1-20 wt.% of a primary alkanolamine; (b) 10-60 wt.% of an alcohol; (c) 0.1-50 wt.% of water; (d) 5-50 wt.% of a polar organic solvent; and (e) 0.01-3 wt.% of a corrosion inhibitor.

Description

  The present invention relates to a photoresist stripping composition, and relates to an integrated photoresist stripping agent that can be used for the entire TFT-LCD process.

  In a flat panel display (FPD) manufacturing process, a photo-lithography process is widely used to form a certain pattern on a substrate. Such a photolithography process is mainly composed of a series of processes such as an exposure process, a dry or wet etching process, and ashing, and after applying and exposing a photoresist (Photo Resist) on a substrate, On the other hand, a pattern is formed by dry or wet etching. At this time, the photoresist remaining on the metal wiring is removed using a photoresist remover.

  The composition of the photoresist remover for LCD process that has been used so far is mainly an organic system that does not contain water, and a mixture of 1,2 alkanolamines, polar solvents or glycols has been used. Generally, the photoresist remaining after the etching process is stripped using the above-described photoresist stripper and then washed with water. In this case, metal wiring is corroded, and impurities are generated due to the re-adsorption of the photoresist. There is a problem of being. This is because when alkanolamines are mixed with water, hydroxide ions are generated, and the corrosivity of metals including aluminum is considerably increased. Therefore, a special corrosion inhibitor for preventing the corrosion of the metal wiring is required. However, the conventional corrosion inhibitor has a problem that its cost is high and it is inferior in economy. As a result, particularly recently, an increase in process costs in the manufacture of flat panel displays such as LCDs has been inevitable.

  In the case of a TFT LCD Al wiring film, the modified photoresist must be peeled off. At this time, the weakly basic amine may not be completely peeled off due to the reduced ability of removing the photoresist. Korean Patent No. 10-0950779 discloses a photoresist stripping composition in which a weakly basic alkanolamine contains a tertiary alkanolamine. As a result of using this composition, the stripping of the modified photoresist is perfect. There was a problem that it was not.

  On the other hand, when using a strongly basic alkanolamine activated by water, it is inevitable to damage the Al and Cu wiring films. In order to solve this problem, existing organic LCD stripping solutions are corrosive. Add a small amount of inhibitor. However, when the TFT-LCD photoresist stripping process is performed using a photoresist stripping solution containing water, the water volatilizes depending on the usage time. Corrosion prevention ability and photoresist stripping ability change rapidly. Therefore, until now, there have been many reports on the stripping composition for LCDs with the addition of strong basic alkanolamines and corrosion inhibitors in the organic stripping composition, but stripping for aqueous LCDs using strong basic alkanolamines. It is difficult to find for a liquid composition.

Korean Patent No. 10-095079

Therefore, the present inventors have solved the above-mentioned problems by developing a relatively stable corrosion prevention and photoresist stripper using an azole compound containing a mercapto group as a corrosion inhibitor. Plan.
An object of the present invention is to use an azole compound containing a mercapto group, which is a stripping liquid composition additive for TFT-LCD, as a corrosion inhibitor, to prevent corrosion of Cu and Al, and to prevent photolysis even when the water content changes. An object of the present invention is to provide a water-based photoresist stripper that maintains a constant resist stripping capability.

  One specific example for achieving the above object is as follows: (a) primary alkanolamine 1-20% by weight; (b) alcohol 10-60% by weight; (c) water 0.1-50% by weight; Provided is a photoresist stripper composition for LCD production comprising:) a polar organic solvent 5-50 wt%; and (e) a corrosion inhibitor 0.01-3 wt%.

In another specific example, the primary alkanolamine is monoethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol (2-amino-2-methyl-1). Composition for removing photoresist for LCD, which is at least one selected from the group consisting of 2-propanol, 2-Methylaminoethanol and 3-Aminopropanolamine Offer things.
In another specific example, the alcohol may be ethylene glycol, 1-hexanol, octanol, 1-heptanol, 1-decanol, Provided is a photoresist stripping liquid composition for LCD, which is one or more selected from the group consisting of 2-Heptanol and Tetrahydrofurfurylalcohol.

In another specific example, the corrosion inhibitor is a C ₅ -C ₁₀ heterocyclic compound, and the carbon constituting the ring is one or more atoms selected from the group consisting of N, O, and S. Provided is a photoresist stripping composition for LCD production, which is substituted and has a mercapto group substituted on a carbon atom of the heterocyclic ring.

In another embodiment, the present invention provides a photoresist stripping composition for LCD production, wherein the heterocyclic compound is imidazole.
In another specific example, the corrosion inhibitor includes 2-mercaptobenzimidazole, 2,5-dimercapto-1,3,4-thiadizole (2,5-Dimercapto-1,3,4- There is provided a photoresist stripping composition for LCD production, which is one or more selected from the group consisting of thiadizole) and 2-mercaptobenzothiazole.

In another specific example, the polar organic solvent has a chemical formula of RO (CH ₂ CH ₂ O) H (where R is any one of linear hydrocarbons, branched hydrocarbons, and cyclic hydrocarbons). A photoresist stripper composition for LCD production comprising a glycol having

  In another specific example, the polar organic solvent includes N-methylpyrolidone (NMP), sulfolane, dimethyl sulfoxide (DMSO), dimethylacetamide (DMAC), and monomethylformamide (Monomethylformamide). And a photoresist stripping composition for LCD production, which is one or more selected from the group consisting of:

In one embodiment, a photoresist stripper for LCD production comprising: (a) 1-20% by weight primary alkanolamine; (b) 10-60% by weight alcohol; and (c) 5-70% by weight polar organic solvent. A composition is provided.
In another specific example, the primary alkanolamine is 2-amino-2-methyl-1-propanol. A liquid composition is provided.

  In another specific example, the alcohol may be ethylene glycol, 1-hexanol, octanol, 1-heptanol, 1-decanol, There is provided a photoresist stripping solution composition for LCD, which is at least one selected from the group consisting of 2-Heptanol and Tetrahydrofurfurylalcohol.

Hereinafter, the present invention will be described in detail.
In the present invention, the constituent of the photoresist stripping solution according to the present invention uses 0.01 to 3% by weight of an azole compound containing a mercapto group as a corrosion inhibitor. When the weight ratio of the corrosion inhibitor is too low, the corrosion prevention effect on the metal wiring film hardly appears. In particular, when the content of the corrosion inhibitor is low, the corrosion prevention effect decreases significantly as the amount of water decreases. When the weight ratio of the corrosion inhibitor is too high, the photoresist stripping ability is weakened. When 3% by weight of the corrosion inhibitor was used in the composition according to the present invention, it was confirmed that there was no abnormality in corrosion prevention and peeling ability. Since the corrosion inhibitor is expensive, it is not necessary to add more than necessary.

  In addition, other corrosion inhibitors can be added to further improve the corrosion prevention ability of the LCD pattern component elements such as Mo, Al and Cu. Then, a secondary alkanolamine having a pH of 11 (based on a 10% aqueous solution) or higher (eg, monoethanolamine (MEA), monoisopropanolamine, MIPA), 2-methylaminoethanol, 2 -MAE), diethylethanolamine (Diethylethanolamine, DEEOA) and MDEA, MDMA, DEEOA mixed liquid) content may be 1-20 wt%. The content of water may be 0.1 to 50% by weight, and the content of alcohol (eg; ethylene glycol (Ethylene Glycol, EG, boiling point: 197.7 ° C.)) may be 10 to 60% by weight. -Methylpyrrolidone (N-methylpyrollidone, NMP), dimethylsulfoxide (DMSO), dimethylacetamide (DMA), N-methylformamide (NMF), etc. are used alone or in a mixture of 5 to 50% by weight. be able to.

  In order to improve the detergency after peeling, the glycols include diethylene glycol monoethyl ether (EDG), diethylene glycol monobutyl ether (BDG), triethylene glycol ether (TRIG), etc. 60% can be used alone or in combination. The weight ratio is suitably 5 to 50% by weight. If the amount is too small, the cured photoresist cannot be sufficiently dissolved.

  The weight ratio of the primary alkanolamine having a pH of 11 or higher and a boiling point of 150 ° C. or higher with respect to the stripping solution is suitably 1 to 20% by weight. A problem arises in the peeling force due to loss accompanying the progress of the process. If the amount exceeds 20% by weight, a corrosion inhibitor must be added relatively, and the metal wiring film may be corroded, resulting in an increase in manufacturing cost. Water content is 0.1 to 50% by weight, alcohol (boiling point: 150 ° C or higher, eg, ethylene glycol (Ethylene Glycol, EG, boiling point: 197.7 ° C), tetrahydrofurfuryl alcohol (Tetrahydrofurfurylalcohol, THFA, boiling point: 178 10) to 60% by weight is appropriate, and if the ratio is too small, the corrosion preventing ability of the Cu wiring film may be lowered.

  Moreover, when the ratio of water is too high, the Al metal wiring may be corroded, and the photoresist stripping effect is reduced. If alcohol is not added, it will not affect corrosion prevention and stripping ability, but during the stripping process, the process temperature (above 40 ° C) and the exhaust pressure in the equipment will volatilize water, reducing the stripping solution life. The Accordingly, when the LCD photoresist stripping process proceeds, an appropriate amount of alcohol may be mixed and used according to the usage time of the stripping solution.

  The photoresist stripping composition according to the present invention is an aqueous system containing water. The aqueous stripping solution containing water is more activated in the basicity of the amine than the organic stripping solution. Accordingly, in the flat panel display manufacturing process, the removal capability for the modified photoresist remaining after the progress of dry etching, implanting and hard baking processes is lower than that of generally used organic LCD stripping solutions. Much better when temperature is applied. The application of low process temperatures allows for a reduction in manufacturing costs for flat panel displays. Moreover, since the stripping composition according to the present invention uses an optimum corrosion inhibitor, it can be applied to both aluminum wiring and copper wiring, and can be introduced into an organic film and a COA process.

Moreover, the peeling of the photoresist can be effectively assisted by mixing one or more glycols. Glycols serve to spread the dissolved photoresist widely to the release agent and are useful for rapid removal. In the case of the above-described glycol, the structure is RO (CH ₂ CH ₂ O) H, where “R” represents any one of a linear hydrocarbon, a branched hydrocarbon, and a cyclic hydrocarbon.

  More specifically, diethyleneglycolmonomethylether (MDG), diethyleneglycolmonoethylether (EDG), diethyleneglycolmonobutylether (BDG), triethyleneglycolether (TRIG), and the like can be used. .

The weight ratio of glycols to the total composition is suitably 10 to 70% by weight, and one or two or more of those corresponding to the above-mentioned RO (CH ₂ CH ₂ O) H can be used in combination.
On the other hand, 2-amino-2-methyl-1-propanol (hereinafter referred to as “AMP”), which has a steric hindrance even with a primary strong base alkanolamine, does not contain water. In the organic composition to which only alcohols are added, the modified photoresist can be completely removed without using a corrosion inhibitor, and corrosion of Al and Cu wiring can be prevented.

Since AMP is a primary amine, water and OH ⁻ are generated by the following reaction formula (1) to corrode the metal wiring film. In the absence of water, the corrosion reaction between the amine and the metal is represented by the following reaction formula (2). At this time, although AMP is a primary amine, since the R group in the following reaction formula (2) is very large, steric hindrance occurs and suppresses the corrosion reaction. On the other hand, since AMP is a primary strong basic amine, it is advantageous for removing the modified photoresist.

(1) Corrosion reaction between amine and copper in aqueous solution
_{RNH 2 + H 2 O → RNH} 3 + + OH -
^{Cu 2+ + 2OH - → Cu (} OH) 2 (s)
Cu (OH) ₂ (s) + 4RNH ₃ ⁺ → [Cu (RNH ₂ ) ₄ ]

(2) Corrosion reaction between amine and copper in organic solution
Cu ²⁺ + 4RNH ₂ → Cu (RNH ₂ ) ₄ ²

  Therefore, the present invention is excellent in corrosion prevention and stripping ability in the TFT-LCD photoresist stripping process even though water is contained in the copper and aluminum wiring, and is removed from the modified photoresist after the process has progressed. It is possible to provide a photoresist stripping composition that is excellent in ability and overcomes the disadvantages while maintaining the advantages of the existing invention.

  The photoresist stripper according to the present invention is excellent in the removal capability of the modified photoresist after the progress in the manufacturing process of a semiconductor or flat panel display, and can be applied to both aluminum wiring and copper wiring. If it can be introduced into the process and mixed with an alcohol having a boiling point of 150 ° C. or higher and water, the corrosion prevention ability is improved and the use time can be increased.

FIG. 1 is a representative photograph showing a microscope produced by heat-treating an Al metal film wiring glass substrate from which the photoresist has not been removed in an oven at a temperature of 170 ° C. for 10 minutes. FIG. 2 shows the result of immersing a substrate heat-treated (170 ° C./10 minutes) in a stripping solution maintained at a temperature of 50 ° C. for 30 seconds, and evaluating the degree of removal of the modified photoresist. As a result, the photoresist is removed. It is a microscope representative photograph showing that it remains on the substrate without being applied (corresponding to X). FIG. 3 shows a result of immersing a substrate heat-treated (170 ° C./10 minutes) in a stripping solution maintained at a temperature of 50 ° C. for 30 seconds and evaluating the degree of removal of the modified photoresist. It is a microscope representative photograph showing that the portion remains on the substrate without being removed (corresponding to Δ).

FIG. 4 shows the result of immersing a substrate heat-treated (170 ° C./10 minutes) for 30 seconds in a stripping solution maintained at a temperature of 50 ° C., and evaluating the degree of removal of the modified photoresist. It is a microscope representative photograph showing that it was removed (corresponding to ◎). FIG. 5 is a representative photograph taken by SEM of a Cu metal film wiring glass substrate from which the photoresist has not been removed. FIG. 6 shows that the result of immersing a Cu glass substrate from which the photoresist has not been removed in a stripping solution maintained at a temperature of 50 ° C. for 10 minutes and evaluating the degree of corrosion of the Cu surface corresponds to (◎). This is a representative SEM photograph.

FIG. 7 shows that the Cu glass substrate from which the photoresist has not been removed is immersed in a stripping solution maintained at a temperature of 50 ° C. for 10 minutes, and the degree of corrosion on the Cu surface is evaluated, and the result is (?). This is a representative SEM photograph. FIG. 8 shows that the result of immersing a Cu glass substrate from which the photoresist has not been removed in a stripping solution maintained at a temperature of 50 ° C. for 10 minutes and evaluating the degree of corrosion of the Cu surface corresponds to (Δ). This is a representative SEM photograph. FIG. 9 shows that the result of immersing a Cu glass substrate from which the photoresist has not been removed in a stripping solution maintained at a temperature of 50 ° C. for 10 minutes and evaluating the degree of corrosion of the Cu surface corresponds to (X). This is a representative SEM photograph.

  Hereinafter, the present invention will be described in detail with reference to the following examples. However, the following examples only illustrate the present invention and do not limit the contents of the present invention.

Example 1
The modified photoresist stripping ability and corrosion prevention ability test for evaluating the performance of the photoresist stripping composition according to the present invention was carried out by the following method. The stripping composition contains 1% by weight of 2-mercaptobenzimidazole as a corrosion inhibitor, and the remaining specific components such as amine and water and the composition (% by weight) are as shown in Table 1 below. An Al metal film wiring glass substrate from which the photoresist was not removed was heat-treated in an oven at a temperature of 160 ° C. for 10 minutes. While maintaining the prepared stripping composition at 50 ° C., the manufactured substrate was immersed in the stripping composition for 30 seconds, and the degree of removal of the modified photoresist was evaluated.
Further, while maintaining the stripping solution composition at 50 ° C., the Cu metal film wiring glass substrate was immersed in the stripping solution composition for 10 minutes, and the presence or absence of corrosion of the Cu wiring film was evaluated. As the evaluation standard, a Cu metal film wiring glass substrate immersed in acetone for 10 minutes was used as a control group (Table 1).

The results of the above experiment are shown in Table 1 with the following symbols.
[Modified photoresist (PR) stripping ability of Al wiring]
◎: Modified photoresist completely removed Δ: Trace amount of modified photoresist remains X: 1/3 or more of modified photoresist remains

[Corrosion degree of Cu wiring]
◎: Corrosion level is the same as that of the control group substrate ○: The film thickness is the same as that of the control group substrate, but weak corrosion occurs on the surface △: The film thickness is decreased compared to the control group substrate and the surface is corroded X: Cu wiring film was corroded and the film thickness was reduced by 1/2 or more.

MEA: Monoethanol amine
MIPA: Monoisopropanol amine
DIPA: Diisopropanol amine
TIPA: Triisopropanol amine
AMP: 2-amino-2-methyl-1-propanol

2-MAE: 2- (Methylamino) ethanol
MDEOA: Methyldiethanol amine
DEEOA: Diethylethanol amine
AEEOA: Aminoethylethanol amine
3-APN: 3-Aminopropanol amine
MDEA: Methyldiethanolamine

MDMA: Methyldimethanolamine
EG: Ethylene glycol (EthyleneGlycol)
EDG: Diethyleneglycolmonoethylether
NMP: N-methylpyrrolidone
THFA: Tetrahydrofurfurylalcohol
MBI: 2-Mercaptobenzimidazole

  As shown in Table 1, under the composition conditions of the present invention containing 2-mercaptobenzimidazole as a corrosion inhibitor, a composition satisfying both the modified PR peeling ability and the Cu wiring corrosion prevention ability is obtained.

Comparative Example 1
The experiment was performed in the same manner as in Example 1 except that it did not contain a corrosion inhibitor (MBI, 2-mercaptobenzimidazole). The results are as shown in Table 2, and the abbreviations described in Table 2 are as described above.

  As shown in Table 2, the modified photoresist stripping ability decreased or the Cu wiring corrosion prevention ability was remarkably reduced under the conditions in which a primary corrosion rate was not added while using a primary alkanolamine and water in an aqueous photoresist.

Example 2
The experiment was performed in the same manner as in Example 1 except that only the type of Cu corrosion inhibitor or the alcohol content was changed as shown in Table 3 below. The results are shown in Table 3.

BIMD: Benzimidazole
IMD: Imidazole
4-MIMD: 4-methylimidazole
BTA: Benzotriazole
TTA: Tetrazole
MBI: 2-Mercaptobenzimidazole
2,5-DTA: 2,5-Dimercapto-1,3,4-thiadizole (2,5-Dimercapto-1,3,4-thiadizole)
MBT: 2-Mercaptobenzothiazole

  As can be seen from the results in Table 3, when a compound containing no mercapto group was used as a corrosion inhibitor, problems such as corrosion of the wiring or remaining of the corrosion inhibitor after the process occurred. -Corrosion prevention for azole compounds containing mercapto groups such as 2-Mercaptobenzimidazole, 2,5-dimercapto-1,3,4-thiadizole and 2-mercaptobenzothiazole When used as an agent, it was confirmed that the corrosion of the wiring was almost completely prevented and there was no residual corrosion inhibitor.

Example 3
An experiment was conducted in the same manner as in Example 1 using AMP (2-amino-2-methyl-1-propanol) having steric hindrance as the primary amine. The results are shown in Table 4.

  As shown in Table 4, AMP was modified not only when water and a corrosion inhibitor were added, but also when a metal wiring film corrosive agent was not used in an organic composition in which only alcohols were added without water. It was confirmed that the photoresist can be completely removed and corrosion of the Al and Cu wirings can be effectively prevented.

  As described above, if an azole compound containing a primary ethanolamine that is a strong base and a mercapto group is used as a corrosion inhibitor during the production of an aqueous photoresist stripper, the photoresist is significantly modified. It is possible to both completely peel off and prevent corrosion of copper wiring. In addition, when AMP, which is a primary alkanolamine having steric hindrance, is used in an organic composition not containing water, the copper wiring was not corroded even without a corrosion inhibitor.

  Although the present invention has been described above with reference to exemplary embodiments, those skilled in the art to which the present invention pertains can implement various changes without departing from the scope of the present invention. It will be understood that equivalents can be substituted.

  In addition, various modifications may be made to adopt a particular situation and material to the teachings of the invention without departing from the essential scope thereof. Accordingly, the present invention is not limited to the specific embodiments disclosed as the best mode planned for the practice of the invention, but is construed to include all embodiments belonging to the claims of the present invention. There must be.

Claims (11)

(A) 1-20% by weight of primary alkanolamine;
(B) 10-60% by weight of alcohol;
(C) 0.1 to 50% by weight of water;
A photoresist stripping composition for LCD production, comprising: (d) 5-50% by weight of a polar organic solvent; and (e) 0.01-3% by weight of a corrosion inhibitor.   Primary alkanolamines are monoethanolamine, monoisopropanolamine, 2-amino-2-methyl-1-propanol, 2-methyl 2. The photoresist stripping solution composition for LCD according to claim 1, wherein the composition is one or more selected from the group consisting of 2-Methylaminoethanol and 3-Aminopropanolamine. 3. object.   Alcohols include ethylene glycol, 1-hexanol, octanol, 1-heptanol, 1-decanol, and 2-heptanol. 2. The photoresist stripping composition for LCD according to claim 1, wherein the composition is one or more selected from the group consisting of tetrahydrofurfuryl alcohol and tetrahydrofurfurylalcohol. The corrosion inhibitor is a C ₅ -C ₁₀ heterocyclic compound, and the carbon constituting the ring is substituted with one or more atoms selected from the group consisting of N, O and S; 2. The photoresist stripping composition for LCD production according to claim 1, wherein a mercapto group is substituted on the carbon atom of the LCD.   The photoresist stripping composition for LCD production according to claim 4, wherein the heterocyclic compound is imidazole.   Corrosion inhibitors include 2-mercaptobenzimidazole, 2,5-dimercapto-1,3,4-thiadizole and 2-mercaptobenzothiazole. 2. The photoresist stripping composition for LCD production according to claim 1, wherein the composition is one or more selected from the group consisting of (2-Mercaptobenzothiazole). A glycol in which the polar organic solvent has the chemical formula R—O (CH ₂ CH ₂ O) H (where R is any one of linear hydrocarbons, branched hydrocarbons, or cyclic hydrocarbons). The photoresist peeling liquid composition for LCD manufacture of Claim 1 containing this.   The polar organic solvent was selected from the group consisting of N-methylpyrrolidone (NMP), sulfolane, dimethyl sulfoxide (DMSO), dimethylacetamide (DMAC), and monomethylformamide (Monomethylformamide). The photoresist stripping composition for LCD production according to claim 1, wherein the composition is one or more. (A) 1-20% by weight of primary alkanolamine;
A photoresist stripping composition for LCD production comprising (b) 10-60 wt% alcohol; and (c) 5-70 wt% polar organic solvent.   The photoresist strip for LCD production according to claim 9, wherein the primary alkanolamine is 2-amino-2-methyl-1-propanol. Liquid composition.   Alcohols include ethylene glycol, 1-hexanol, octanol, 1-heptanol, 1-decanol, and 2-heptanol. 10. The photoresist stripping composition for LCD according to claim 9, wherein the composition is one or more selected from the group consisting of tetrahydrofurfuryl alcohol and tetrahydrofurfurylalcohol.