WO2012134226A2 - Cleaning-solution composition for photolithography - Google Patents

Abstract

The present invention relates to a cleaning-solution composition for photolithography, which prevents pattern collapse and an increase in the numerical value of line width roughness (LWR), which might occur during the formation of a photoresist pattern, and hardens a pattern surface to improve etch resistance. The cleaning-solution composition comprises: a water-soluble polymer including a monomolecular acid compound expressed in chemical formula 1 or a repeating unit expressed in chemical formula 3; and a solvent.

Description

Cleaning liquid composition for photolithography

The present invention relates to a cleaning liquid composition, and more particularly, to prevent pattern collapse and line width roughness (LWR) generated during photoresist pattern formation, and to increase etching resistance by curing the surface of the pattern through a heating process. The present invention relates to a cleaning liquid composition for photolithography.

With the miniaturization and integration of semiconductor devices, resist materials used in the manufacture of semiconductor devices have also been improved to cope with such miniaturization and integration. However, as miniaturization and integration of semiconductor devices have progressed, various problems have arisen due to the implementation of fine patterns. For example, the yield of a semiconductor device may be lowered due to defects such as a resist pattern defect, an increase in a numerical value of line width roughness (LWR), and a pattern collapse.

In order to produce a semiconductor device having a pattern resolution of 30 nm or less, extreme ultraviolet lithography (EUVL) technology with a wavelength of 13.4 nm of an exposure source is used, and in order to use the above technique, You must overcome the problem. Phenomenon such as increase in resist scum, line width roughness (LWR), pattern collapse, etc. is mostly caused by deterioration of the photoresist composition. However, the above-described defects can be overcome by a cleaning technique. For example, in general, cleaning is performed using pure water (cleaning liquid) during the process. However, when surfactant is added to the cleaning liquid to reduce the surface tension of the cleaning liquid, the pattern falling during wafer drying through spin out is prevented. Partially insoluble polymers which are not dissolved in the resist pattern due to the hydrophilic group of the surfactant can be removed together, resulting in suppressing an increase in the numerical value of the line width roughness (LWR). However, since the cleaning method causes rounding of the upper part of the pattern (a phenomenon in which the angular portion is rounded), the desired pattern shape may not be obtained, and by the deformation of the pattern shape, the etching resistance of the pattern during the etching process is performed. Is degraded, and other problems may arise.

Accordingly, an object of the present invention is to provide a cleaning liquid composition for photolithography which can prevent the pattern collapse of the photoresist pattern and the numerical increase of the line width roughness (LWR), and harden the pattern surface to increase the etching resistance.

In order to achieve the above object, the present invention is an acidic monomolecular compound represented by the following formula (1); And a cleaning liquid composition for photolithography (hereinafter referred to as a first cleaning liquid composition if necessary) containing a solvent.

[Formula 1]

In Formula 1, each R is independently a hydrogen atom (H), an alcohol group (-OH), a methyl group (-CH ₃ ), a sulfonic acid group (-SO ₃ H) or an amine group (-NH ₂ ), n is It is an integer of 1-10.

In addition, the present invention is a water-soluble polymer comprising a repeating unit represented by the formula (3); And a cleaning liquid composition for photolithography (hereinafter referred to as a second cleaning liquid composition if necessary) containing a solvent.

[Formula 3]

In Formula 3, R ₁ to R ₃ are each independently a hydrogen atom (H) or a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms, and X is not present, or is a linear or branched carbon group having 1 to 20 carbon atoms. Or a cyclic hydrocarbon group.

The present invention also provides a method for forming a photoresist film on a semiconductor substrate on which an etched layer is formed; Exposing and developing the photoresist film to form a photoresist pattern; Washing the photoresist pattern with the cleaning liquid composition for photolithography; And drying the washed photoresist pattern, heating (hard baking) to 110 to 200 ° C., and curing the photoresist surface.

The first cleaning liquid composition according to the present invention comprises an acidic monomolecular compound, and the second cleaning liquid composition according to the present invention includes a water-soluble polymer in the form of a salt. The pattern collapse and line width of the photoresist pattern through a washing and heating process The increase in the roughness LWR can be prevented and the surface of the pattern can be cured to increase the etching resistance.

Hereinafter, the present invention will be described in detail.

The cleaning liquid composition (first cleaning liquid composition) for photolithography according to the present invention includes an acidic monomolecular compound represented by the following formula (1), and a solvent.

[Formula 1]

In Formula 1, each R is independently a hydrogen atom (H), an alcohol group (-OH), a methyl group (-CH ₃ ), a sulfonic acid group (-SO ₃ H) or an amine group (-NH ₂ ), n is It is an integer of 1-10. That is, when n is 2 or more, R of each n repeating unit may be the same or different.

The acidic monomolecular compound used in the present invention may crosslink with the photosensitive polymer on the surface of the photoresist pattern when heated (hard bake) (see Formula 2 below) to cure the surface of the photoresist pattern. The content of the acidic monomolecular compound is 0.001 to 5% by weight, preferably 0.005 to 1% by weight, more preferably 0.01 to 0.5% by weight, most preferably 0.01 to 0.1, based on the total cleaning liquid composition for photolithography. Weight percent. If the content of the acidic monomolecular compound is less than 0.001% by weight, the surface of the pattern may not be cured even when heated. If the content of the acidic monomolecular compound is more than 5% by weight, the photoresist pattern may be damaged by increasing the acidity.

[Formula 2]

In Chemical Formula 2, R and n are as defined in Chemical Formula 1, and A and B represent functional groups included in conventional photosensitive polymers.

Representative examples of the acidic monomolecular compound represented by Chemical Formula 1 may include an acidic monomolecular compound represented by the following Chemical Formulas 1a to 1l.

[Formula 1a]

[Formula 1b]

[Formula 1c]

[Formula 1d]

[Formula 1e]

[Formula 1f]

[Formula 1g]

[Formula 1h]

Formula 1i]

[Formula 1j]

[Formula 1k]

[Formula 1l]

On the other hand, the cleaning liquid composition (second cleaning liquid composition) for photolithography according to the present invention includes a water-soluble polymer and a solvent comprising a repeating unit represented by the following formula (3).

[Formula 3]

In Formula 3, R ₁ to R ₃ are each independently a hydrogen atom (H) or a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10, more preferably 1 to 5 carbon atoms, eg For example, it is an alkyl group or an aryl group, preferably an alkyl group, X is absent or a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, eg For example, it is an alkylene group or an arylene group, Preferably it is an alkylene group, R <_1> -R <_3> and X may connect with each other and form a cyclic structure.

The water-soluble polymer used in the present invention includes a water-soluble monomer in a salt form, and crosslinks and reacts with the photosensitive polymer on the surface of the photoresist pattern during heating (hard bake) to cure the surface of the photoresist pattern. With respect to all the repeating units constituting the water-soluble polymer of the present invention, the mol% of the repeating unit of Formula 3 is 1 to 100 mol%, preferably 10 to 90 mol%, more preferably 20 to 80 mol%, The remaining repeating units may include conventional repeating units used for the water soluble polymer.

Representative examples of the repeating unit represented by Formula 3 may include repeating units represented by the following Formulas 3a to 3b.

[Formula 3a]

[Formula 3b]

In addition, as a preferable example of the water-soluble polymer including the repeating unit represented by the formula (3), can be illustrated a water-soluble polymer represented by the following formula (4).

[Formula 4]

In Formula 4, R ₁ to R ₃ and X are as defined in Formula 3, R ₄ is a hydrogen atom (H) or a methyl group (-CH ₃ ), Y is a hydroxy group (-OH), an amine group (- NH ₂ ), secondary and tertiary amine groups (NH, N), carbonyl groups (-C (= 0)-), ester groups (-C (= 0) O-) and mixtures thereof A linear, branched or cyclic hydrocarbon group containing 1 to 10 carbon atoms, preferably 1 to 7 carbon atoms, wherein m and n are mole% of the repeating units constituting the water-soluble polymer, respectively, 0 to 99 mole% And 1 to 100 mol%, preferably 10 to 90 mol% and 10 to 90 mol%, more preferably 20 to 80 mol% and 20 to 80 mol%, respectively.

As a representative example of the water-soluble polymer represented by the formula (4), it is possible to illustrate the water-soluble polymer represented by the formula (4a) to 4h.

[Formula 4a]

[Formula 4b]

[Formula 4c]

[Formula 4d]

[Formula 4e]

[Formula 4f]

[Formula 4g]

[Formula 4h]

In Formulas 4a to 4h, m and n are as defined in Formula 2.

The water-soluble polymer may be prepared by a conventional polymerization method, for example, may be prepared according to the same method as the preparation example. The weight average molecular weight of the water-soluble polymer is preferably 1,000 to 100,000, more preferably 1,000 to 10,000, most preferably 1,000 to 5,000. If the weight average molecular weight of the water-soluble polymer is less than 1,000, the pattern surface may not be cured even when heated (hard bake). If the weight average molecular weight is 100,000, the solubility of water-soluble polymer in water is poor. There is a possibility that a defect may occur.

The content of the water-soluble polymer is 0.001 to 5% by weight, preferably 0.005 to 1% by weight, more preferably 0.01 to 0.5% by weight, most preferably 0.01 to 0.1% by weight based on the total cleaning liquid composition for photolithography. to be. If the content of the water-soluble polymer is less than 0.001% by weight, the surface of the pattern may not be cured even when heated (hard bake). If the content of the water-soluble polymer exceeds 5% by weight, there may be a problem of scum defects. .

The solvent used in the present invention is for washing the photoresist pattern, and water (pure water) can be used, and a mixed solvent obtained by mixing water and a water-soluble organic solvent can be used, if necessary. As the water-soluble organic solvent, a monohydric or polyhydric alcohol-based organic solvent may be used, and the monohydric alcohol may be methanol, ethanol, propanol, isopropyl alcohol (IPA), or the like. The polyhydric alcohol may be exemplified by ethylene glycol, propylene glycol, diethylene glycol, glycerin, alkyl ether or esters thereof, and the like. The content of the solvent is the remaining components except for the acidic monomolecular compound with respect to the cleaning liquid composition for the entire photolithography, and when the mixed solvent is used as the solvent, the content of the water-soluble organic solvent is 0.01 to the total solvent, 50% by weight, preferably 0.1 to 20% by weight. When using the mixed solvent, if the content of the water-soluble organic solvent exceeds 50% by weight relative to the total solvent, the photoresist pattern is dissolved in the solvent may cause a pattern distortion phenomenon.

The cleaning liquid composition for photolithography according to the present invention may further include additives such as a surfactant as necessary. The surfactant is for lowering the surface tension of the cleaning liquid composition. For example, the surfactant suppresses pattern collapse by lowering stresses between patterns generated when spin-drying the cleaning liquid composition. As the surfactant, a conventional water-soluble surfactant can be used. For example, a water-soluble anionic surfactant, a water-soluble nonionic surfactant, a water-soluble cationic surfactant, a water-soluble amphoteric surfactant or the like alone or in combination of two or more. It can be mixed and used. Specific examples of the water-soluble anionic surfactants include lauryl triethanolamine, ammonium lauryl sulfate, triethanol amine polyoxyethylene alkyl ether sulfates, and the like. Specific examples of the activator include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene higher alcohol ether, polyoxyethylene octyl phenyl ether, and polyoxy. Ethylene nonyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyethylene derivative, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tree Stearate, polyoxyethylene sorbent Tanmonooleate, polyoxyethylene sorbitan trioleate, tetraoleic acid polyoxyethylene sorbite, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol distearate, polyethylene glycol monooleate, polyoxyethylene alkyl Amine, polyoxyethylene cured castor oil, alkanolamide, and the like, and specific examples of the water-soluble cationic surfactant include coconut amine acetate, stearyl amine acetate, and the like. Specific examples of the water-soluble amphoteric surfactant may include laurylbetaine, stearylbetaine, lauryl dimethyl amineoxide (RDMAO), 2-alkyl-N-carboxymethyl- N-hydroxyethyl imidazolinium betaine etc. can be illustrated. As commercially available surfactants, such as 3M's NOVEC 4200 and FC-4430, Dupont's FSN and FSO, Air-product's S-465 and S-485W, Rhodia's 25R2 and L-62, etc., NEOS's 212M , 215M, etc., DIC's F-410, F-477, etc., WAKO's NCW1001, NCW1002, etc. can be used individually or in mixture.

When using the surfactant, the content of the surfactant is 0.001 to 5 parts by weight, preferably 0.001 to 1 part by weight, more preferably 0.01 to 0.5 part by weight based on 100 parts by weight of the total cleaning liquid composition for photolithography. And most preferably 0.05 to 0.1 parts by weight. When the content of the surfactant is less than 0.001 part by weight based on 100 parts by weight of the total cleaning liquid composition for photolithography, pattern collapse may occur, and when it exceeds 5 parts by weight, it may act as an impurity.

The cleaning liquid composition according to the present invention may be used in a cleaning process of a conventional photolithography process, and may harden the surface of the photoresist pattern formed through a heating process after cleaning. For example, in the method of forming a photoresist pattern according to the present invention, (a) forming a photoresist film on a semiconductor substrate on which an etched layer is formed, and (b) exposing and developing the photoresist film to form a photoresist pattern. (C) washing the photoresist pattern with the cleaning liquid composition for photolithography, and (d) drying the cleaned photoresist pattern by spin out or spin dry. And hardening the photoresist surface by heating (hard bake) to 110 to 200 ° C, preferably 130 to 150 ° C.

In the method of forming the photoresist pattern, the cleaning of the photoresist pattern may be by secondary cleaning by the cleaning liquid composition of the present invention after the first cleaning using pure water, the heating temperature during the heating (hard bake) process, If it is less than 110 ° C, the pattern may not be cured. If the heating temperature exceeds 200 ° C, the pattern may be collapsed by thermal decomposition of the resist itself.

Hereinafter, the present invention will be described in more detail with reference to specific examples. The following examples are intended to illustrate the invention, and the invention is not limited by the following examples.

Examples 1-42, Comparative Examples 1-4 Preparation and evaluation of the cleaning liquid composition for photolithography

A. Preparation of Cleaning Liquid Composition for Photolithography

According to the composition of Tables 1 to 4, the acidic monomolecular compound, the solvent, and the surfactant were mixed for 4 hours to completely dissolve the acidic monomolecular compound and the surfactant in the solvent, and then the water-soluble filter having pores of 0.1 μm size. It filtered through to prepare a cleaning liquid composition for photolithography.

B. Formation of Photoresist Pattern and Evaluation of Cleaning Liquid Composition

(a) For forming the photoresist pattern and evaluating the cleaning liquid composition, a photosensitive polymer was synthesized as follows. 11methyl g (0.5 mol) 2-methyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl methacrylate (3-hydroxy-1-adamantyl methacrylate) 23.6 g (0.1 mol), 68.0 g (0.4 mol) 2-oxotetrahydrofuran-2-yl methacrylate and azobis (isobutyronitrile) (AIBN) 6.6 g was dissolved in 125 g of anhydrous tetrahydrofuran (THF), degassed using an ampoule by freezing method, and the reaction was then polymerized at 68 ° C. for 24 hours. After the polymerization was completed, the reaction solution was slowly dropped into excess diethyl ether to precipitate, and the precipitate was dissolved in tetrahydrofuran (THF) again, and then precipitated again in diethyl ether to form a photosensitive terpolymer for photoresist. (Yield: 53%, weight average molecular weight (Mw): 8,500, polydispersity index (PDI): 1.8).

(b) Next, as the photosensitive polymer synthesized in (a), a photoacid generator, 10 parts by weight of diphenyl paratoluenylsulfonium nona plate (TPS-NF), base stabilizer (100 parts by weight of the photosensitive polymer) quencher), 20 parts by weight of triethanolamine based on 100 parts by weight of the photoacid generator is added to propylene glycol monomethyl ether acetate (PGMEA) and stirred for at least 12 hours to completely dissolve, and then a nylon filter having pores having a size of 0.01 μm. A photoresist composition was prepared by sequentially filtering through a polytetrafluoroethylene (PTFE) material filter.

(c) spin coating the photoresist composition prepared in (b) on the etched layer of the silicon wafer to form a photoresist thin film (film), and then heating (prebaking) at 100 ° C. for 60 seconds. (I) exposure with ArF ASML 1200B equipment with numerical aperture (NA) 0.85 (Examples 1-37, Comparative Examples 1-2), or (ii) extreme ultraviolet lithography (EUVL). Exposure was performed with an exposure machine (Examples 38 to 42, Comparative Examples 3 to 4), and then heated at 125 ° C. for 60 seconds (post exposure bake: PEB). This baked (heated) wafer was developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH) for 30 seconds, thereby (i) 1: 1 line and space (L / S) having a film thickness of 140 nm and a line width of 70 nm. (line / space) pattern (Comparative Examples 1 to 2) or (ii) 1: 1 line and space (L / S: line / space) pattern (Comparative Examples 3 to 4) having a film thickness of 60 nm and a line width of 30 nm. Formed. The photoresist film thickness was measured using a KLA company's measurement equipment, Opti-2600, and using an electron microscope (Critical Dimension Scanning Electron Microscope: CD-SEM, device name: S9220, manufacturer: Hitachi), the pattern of the pattern formed Collapse line width (unit: nm) and line width roughness (LWR, unit: nm) were measured. Here, the criterion of the pattern collapse was calculated by measuring the point at which the end edge pattern of the L / S pattern falls. In addition, since the resist scum present at the bottom of the line width also affects the numerical value of the line width roughness (LWR), the improvement (decrease) of the line width roughness (LWR) also means that the resist scum is also improved. do. The results are shown in Tables 1 and 4 below.

(d) developing the photoresist pattern in the same manner as in (c), and then washing with pure water for 30 seconds, spraying the cleaning liquid composition prepared in step A on the surface of the developed photoresist pattern and contacting for 15 seconds, After drying the wafer through spin drying, heating (hard bake) at 110 to 160 ° C. (i) 1: 1 line and space (L / S: line / space) pattern having a thickness of 140 nm and a line width of 70 nm (implemented) Examples 1-37) or (ii) 1: 1 line and space (L / S: line / space) patterns (Examples 38-42) having a film thickness of 60 nm and a line width of 30 nm were formed. The pattern collapse line width (unit: nm) and line width roughness (LWR, unit: nm) of the photoresist pattern formed by the same method as in (c) were shown in Tables 1 to 4 below, and Examples 1 to 12. The relative etch rates were measured and shown in Table 1 below. Here, the relative etching rate is a value converted based on Comparative Example 1, the etching rate measurement conditions are BT (breakthrough): CF ₄ (10 sec), ME (main etch): Cl ₂ / HBr / O ₂ (30 sec ).

Table 1

TABLE 2

TABLE 3

Table 4

From the above results, when proceeding to hard bake (Comparative Examples 2 and 4) without using the cleaning liquid composition according to the present invention (Comparative Examples 2 and 4), the photoresist pattern is damaged by high heating temperature (pattern flow) is difficult to proceed the process. When using the cleaning liquid composition of this invention, it turns out that there is no pattern damage by pattern surface hardening (increasing etching resistance), and the pattern fall of a pattern and the numerical increase of line width roughness (LWR) can be prevented effectively.

Preparation Examples 1 to 12 Synthesis of Water-Soluble Polymer

According to the composition of Table 5, the monomer of the m repeating unit (

(m-1),

(m-2),

(m-3),

(m-4)) and monomers of n repeat units (

(n-1),

(n-2)) was dissolved in methanol, a reaction solvent, and then, in a nitrogen gas atmosphere, 20 parts by weight of the initiator (product name: V-601, manufacturer: Wako Pure Chemical Inc. Japan) based on 100 parts by weight of the total monomers. ) Was added and mixed and then polymerized at 70 ° C. for 12 hours. After the completion of the polymerization, the polymer solidified in the reaction solvent was separated and dried. When the n-1 monomer was used, the dried polymer was dissolved in pure water at 20% by weight, and then passed through an ion exchange resin to remove chlorine (Cl) ions. Next, sulfuric acid in an equivalent ratio (molar ratio) to n repeat units of the polymerized polymer was added and stirred for 12 hours to obtain a water-soluble polymer in the form of a salt. The weight average molecular weight (Mw), the polydispersity index (PDI) and the yield of the obtained water-soluble polymer are shown in Table 5 below.

Table 5

[Examples 51 to 85, Comparative Examples 11 to 14] Preparation and Evaluation of Cleaning Liquid Composition for Photolithography

A. Preparation of Cleaning Liquid Composition for Photolithography

According to the composition of Tables 6 to 8, the water-soluble polymer, the solvent and the surfactant are mixed for 4 hours, the water-soluble polymer and the surfactant is completely dissolved in the solvent, and then filtered by a water-soluble filter having a pore size of 0.1 ㎛ A cleaning liquid composition for lithography was prepared.

B. Formation of Photoresist Pattern and Evaluation of Cleaning Liquid Composition

(a) For forming the photoresist pattern and evaluating the cleaning liquid composition, a photosensitive polymer was synthesized as follows. 117.2 g (0.5 mol) 2-methyl-2-adamantyl methacrylate, 3-hydroxy-1-adamantyl methacrylate (3-hydroxy-1-adamantyl methacrylate) 23.6 g (0.1 mol), 68.0 g (0.4 mol) 2-oxotetrahydrofuran-2-yl methacrylate and azobis (isobutyronitrile) (AIBN) 6.6 g was dissolved in 125 g of anhydrous tetrahydrofuran (THF), degassed using ampoule by freezing method, and the reaction was then polymerized at 68 ° C. for 24 hours. After the polymerization was completed, the reaction solution was slowly dropped into excess diethyl ether to precipitate, and the precipitate was dissolved in tetrahydrofuran (THF) again, and then precipitated again in diethyl ether to form a photosensitive terpolymer for photoresist. (Yield: 53%, weight average molecular weight (Mw): 8,500, polydispersity index (PDI): 1.8).

(b) Next, as the photosensitive polymer synthesized in (a), a photoacid generator, 10 parts by weight of diphenyl paratoluenylsulfonium nona plate (TPS-NF), base stabilizer (100 parts by weight of the photosensitive polymer) quencher), 20 parts by weight of triethanolamine based on 100 parts by weight of the photoacid generator is added to propylene glycol monomethyl ether acetate (PGMEA) and stirred for at least 12 hours to completely dissolve, and then a nylon filter having pores having a size of 0.01 μm. A photoresist composition was prepared by sequentially filtering through a polytetrafluoroethylene (PTFE) material filter.

(c) spin coating the photoresist composition prepared in (b) on the etched layer of the silicon wafer to form a photoresist thin film (film), and then heating (prebaking) at 100 ° C. for 60 seconds. (I) exposure with an ArF ASML 1200B instrument with Numerical Aperture (NA) 0.85 (Examples 51-80, Comparative Examples 11-12), or (ii) extreme ultraviolet lithography (EUVL). Exposure was performed with an exposure machine (Examples 81 to 85, Comparative Examples 13 to 14), and then heated at 125 ° C. for 60 seconds (post exposure bake: PEB). This baked (heated) wafer was developed with a 2.38% by weight aqueous solution of tetramethylammonium hydroxide (TMAH) for 30 seconds, thereby (i) 1: 1 line and space (L / S) having a film thickness of 140 nm and a line width of 70 nm. (line / space) pattern (Comparative Examples 11 to 12) or (ii) 1: 1 line and space (L / S: line / space) pattern (Comparative Examples 13 to 14) having a film thickness of 60 nm and a line width of 30 nm. Formed. The photoresist film thickness was measured using a KLA company's measurement equipment, Opti-2600, and using an electron microscope (Critical Dimension Scanning Electron Microscope: CD-SEM, device name: S9220, manufacturer: Hitachi), the pattern of the pattern formed Collapse line width (unit: nm) and line width roughness (LWR, unit: nm) were measured. Here, the criterion of the pattern collapse was calculated by measuring the point at which the end edge pattern of the L / S pattern falls. In addition, since the resist scum present at the bottom of the line width also affects the numerical value of the line width roughness (LWR), the improvement (decrease) of the line width roughness (LWR) also means that the resist scum is also improved. do. The results are shown in Tables 6 and 8 below.

(d) developing the photoresist pattern in the same manner as in (c), and then washing with pure water for 30 seconds, spraying the cleaning liquid composition prepared in step A on the surface of the developed photoresist pattern and contacting for 15 seconds, After drying the wafer through spin drying, heating (hard bake) at 110 to 160 ° C. (i) 1: 1 line and space (L / S: line / space) pattern having a thickness of 140 nm and a line width of 70 nm (implemented) Examples 1-30) or (ii) 1: 1 line and space (L / S: line / space) patterns (Examples 81-85) having a film thickness of 60 nm and a line width of 30 nm were formed. The pattern collapse line width (unit: nm) and line width roughness (LWR, unit: nm) of the photoresist pattern formed by the same method as in (c) were shown in Tables 6 to 8 below, and Examples 51 to 62. , By measuring the relative etch rate is shown in Table 6. Here, the relative etching rate is a value converted based on Comparative Example 11, the etching rate measurement conditions are BT (breakthrough): CF ₄ (10sec), ME (main etch): Cl ₂ / HBr / O ₂ (30sec) Proceeded.

Table 6

TABLE 7

Table 8

From the above results, it is difficult to proceed the process because the photoresist pattern is broken (pattern flow) by the high heating temperature when the hard bake proceeds (Comparative Examples 12 and 14) without using the cleaning liquid composition according to the present invention. When the cleaning liquid composition of the present invention is used, there is no pattern damage due to pattern surface hardening (increasing etching resistance), and it can be seen that the pattern collapse of the pattern and the increase in the numerical value of the line width roughness (LWR) can be effectively prevented.

Since the cleaning liquid composition of the present invention can prevent resist scum, pattern collapse, and the like, and improve pattern roughness, which is generated during the formation of a fine pattern, the cleaning liquid composition may be used to form a fine pattern using extreme ultraviolet lithography (EUVL) technology. It is useful and can improve the etching resistance through pattern surface hardening.

Claims (11)

1. An acidic monomolecular compound represented by Formula 1 below; And

   A cleaning liquid composition for photolithography, comprising a solvent.

   [Formula 1]

   

   In Formula 1, each R is independently a hydrogen atom (H), an alcohol group (-OH), a methyl group (-CH ₃ ), a sulfonic acid group (-SO ₃ H) or an amine group (-NH ₂ ), n is It is an integer of 1-10.
2. The cleaning liquid composition for photolithography according to claim 1, wherein the acidic monomolecular compound represented by Chemical Formula 1 is selected from the group consisting of acidic monomolecular compounds represented by the following Chemical Formulas 1a to 1l.

   [Formula 1a]

   

   [Formula 1b]

   

   [Formula 1c]

   

   [Formula 1d]

   

   [Formula 1e]

   

   [Formula 1f]

   

   [Formula 1g]

   

   [Formula 1h]

   

   Formula 1i]

   

   [Formula 1j]

   

   [Formula 1k]

   

   [Formula 1l]

   
3. The amount of the acidic monomolecular compound is 0.001 to 5% by weight based on the total cleaning liquid composition for photolithography, and the rest is a solvent. Photoresist pattern coating composition.
4. The composition for coating a photoresist pattern according to claim 1, further comprising 0.001 to 5 parts by weight of surfactant based on 100 parts by weight of the total cleaning liquid composition for photolithography.
5. A water-soluble polymer including a repeating unit represented by Formula 3 below; And

   A cleaning liquid composition for photolithography, comprising a solvent.

   [Formula 3]

   

   In Formula 3, R ₁ to R ₃ are each independently a hydrogen atom (H) or a linear, branched or cyclic hydrocarbon group having 1 to 20 carbon atoms, and X is not present, or is a linear or branched carbon group having 1 to 20 carbon atoms. Or a cyclic hydrocarbon group.
6. The cleaning liquid composition for photolithography according to claim 5, wherein the repeating unit represented by Chemical Formula 3 is selected from the group consisting of repeating units represented by the following Chemical Formulas 3a to 3b.

   [Formula 3a]

   

   [Formula 3b]

   
7. The composition for coating a photoresist pattern according to claim 5, wherein the water-soluble polymer is a water-soluble polymer represented by the following Chemical Formula 4.

   [Formula 4]

   

   In Formula 4, R ₁ to R ₃ and X are as defined in Formula 3, R ₄ is a hydrogen atom (H) or a methyl group (-CH ₃ ), Y is a hydroxy group (-OH), an amine group (- NH ₂ ), secondary and tertiary amine groups (NH, N), carbonyl groups (-C (= 0)-), ester groups (-C (= 0) O-) and mixtures thereof A linear, branched, or cyclic hydrocarbon group containing 1 to 10 carbon atoms, wherein m and n are mole% of repeating units constituting the water-soluble polymer, and are 0 to 99 mole% and 1 to 100 mole%, respectively. .
8. The cleaning liquid composition for photolithography according to claim 7, wherein the water-soluble polymer represented by Chemical Formula 4 is selected from the group consisting of water-soluble polymers represented by the following Chemical Formulas 4a to 4h.

   [Formula 4a]

   

   [Formula 4b]

   

   [Formula 4c]

   

   [Formula 4d]

   

   [Formula 4e]

   

   [Formula 4f]

   

   [Formula 4g]

   

   [Formula 4h]

   

   In Formulas 4a to 4h, m and n are as defined in Formula 4.
9. The composition for coating a photoresist pattern according to claim 5, wherein the content of the water-soluble polymer is 0.001 to 5% by weight, and the remainder is a solvent with respect to the entire cleaning liquid composition for photolithography.
10. The composition for coating a photoresist pattern according to claim 5, further comprising 0.001 to 5 parts by weight of the surfactant based on 100 parts by weight of the total cleaning liquid composition for photolithography.
11. Forming a photoresist film on the semiconductor substrate on which the etched layer is formed;

    Exposing and developing the photoresist film to form a photoresist pattern;

    Washing the photoresist pattern with the cleaning liquid composition for photolithography according to any one of claims 1 to 10; And

    Drying the washed photoresist pattern and heating (hard bake) to 110 to 200 ° C. to cure the surface of the photoresist.