TW201500852A - Coating composition for forming fine pattern and method for forming fine pattern using the same - Google Patents

Abstract

A coating composition for forming fine pattern which can minimize the line width and height of the pattern by forming a coating layer to a surface of a photoresist pattern formed by using a negative tone developer, and a method for forming fine pattern using the same are disclosed. The coating composition for forming fine pattern comprises: a polymer of the following Formula 1; and an organic solvent. In Formula 1, R1 is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, R2, R3 and R5 is respectively a hydrogen atom or methyl group, "X" is a hydrocarbon group having 1 to 3 carbon atoms or absent, R4 is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as a terminal of the polymer. "a" is a mol% of repeat unit, and 100 mol% in Formula 1.

Description

Coating composition for forming a fine pattern and method for forming a fine pattern using the same

The present invention relates to a coating composition for forming a fine pattern, and more specifically, to a surface of a resist pattern formed by forming a coating layer to a negatively tunable developer. A coating composition for forming a fine pattern that minimizes the line width and the hole size of the pattern, and a method of forming a fine pattern using the same.

Recently, with the miniaturization and accumulation of semiconductor devices, it is required to form finer patterns. In the formation of the pattern, a finer pattern can be formed by using an improved exposure apparatus, or by introducing an additional process such as a pattern coating process to reduce the size of the pattern.

The photoresist pattern can be formed by using a negative tone developer (negative tone development, NTD) or by using a positive tone developer (positive tone development, PTD). In the negative tone developing method, a pattern can be formed by selectively dissolving and removing the unexposed regions using the negative-tuning developer. In the positive tonal development method, a pattern can be formed by selectively dissolving and removing the exposed regions using the positively modulating developer. Compared with the positive tone development method, the negative tone development method can easily form a contact hole pattern or a groove pattern by forming an inverse pattern of a desired pattern, which is usually due to lack of exposure. Difficult to form. Also, the negative tone developing method can form the photoresist pattern more efficiently because an organic solvent can be used as a developer to remove the unexposed regions.

Meanwhile, as a method of forming a finer pattern by introducing an additional process, a well-known pattern coating method. In the pattern coating method, the interval size of the photoresist pattern is reduced. More specifically, in the pattern coating method, a coating composition including a conventional water-soluble polymer is coated on a photoresist pattern to form a coating having a constant thickness on the photoresist pattern. Layers, and thereby forming a finer pattern. However, when the coating composition containing a conventional water-soluble polymer is coated on the photoresist pattern developed using a negative-tuning developer, the photoresist pattern is excessively cross-linked with the water-soluble polymer having high polarity. Linked, and the pattern may become too fine. The reason is that the acidification ratio of the photoresist pattern developed using the negative-tuning developer (the ratio of the protective group of the photoresist pattern to the carboxyl group (-COOH)) is higher than that of the photoresist pattern developed using a conventional tonal developer. Acidification rate. Therefore, in the case of using a coating composition containing a conventional water-soluble polymer, it is difficult to form a finer pattern, and it is also difficult to form a finer pattern having a constant line width because the line width is large as the temperature changes. Change (ie, coating thickness change). Further, after the formation of the coating layer, impurities (scum) may be formed in the lower layer of the pattern (the boundary region between a line and a space).

Further, when the acidity (pH) of the pattern coating composition containing a conventional water-soluble polymer is higher than 9, the resist pattern is applied during the coating treatment of the coating composition including the basic material. May degrade or dissolve. Further, since the etch resistance of the water-soluble polymer is low, the critical dimension (CD, unit: nanometer) of the spacer pattern of the groove pattern or the contact hole pattern may vary.

Accordingly, it is an object of the present invention to provide a coating composition for forming a fine pattern which can prevent light applied when a coating composition containing a conventional water-soluble polymer is applied to be developed using a negative-tuning developer. The disadvantages generated when the pattern is resisted (pattern dissolution phenomenon, change in line width of the pattern as a function of temperature, generation of impurities), and a method of forming a fine pattern using the same.

In order to achieve the above objects, the present invention provides a coating composition for forming a fine pattern comprising: a polymer of the following formula; and an organic solvent.

In Formula 1, R ₁ is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, and R ₂ , R ₃ and R ₅ are each a hydrogen atom or a methyl group. "X" is a hydrocarbon group having 1 to 3 carbon atoms or is absent, and R ₄ is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as one end group of the polymer, "a" is a repeat The mol% of the unit, and 100 mol% in the formula 1.

The present invention also provides a method of using the coating composition for forming a fine pattern to form a fine pattern comprising the steps of: forming a photoresist layer on a substrate to be etched; by exposing the photoresist layer and using negative tone Developing a photoresist layer to form a photoresist pattern on the photoresist layer; coating the coating composition for forming a fine pattern on the formed photoresist pattern; and heating and developing thereon Applying the photoresist pattern of the coating composition to form a coating layer, wherein the coating composition for forming a fine pattern comprises: a polymer of the following formula 1; and an organic solvent,

In Formula 1, R ₁ is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, and R ₂ , R ₃ and R ₅ are each a hydrogen atom or a methyl group. "X" is a hydrocarbon group having 1 to 3 carbon atoms or is absent, and R ₄ is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as one end group of the polymer, "a" is a repeat The mol% of the unit, and 100 mol% in the formula 1.

The coating composition for forming a fine pattern according to the present invention comprises an organic solvent and a fat-soluble polymer containing a nitrogen atom, and when a coating composition having a water-soluble polymer is used for development by a negative-tuning developer In the case of the photoresist pattern, the coating composition can prevent the formation of defects (pattern dissolution phenomenon, pattern line width change with temperature, formation of foreign matter). Further, the coating composition of the present invention can maximize the difference in dissolution rate between the coating layer formation position and the removal position during development. Therefore, the coating composition of the present invention can be effectively used to form a fine pattern, and can achieve a stable pattern line width during semiconductor fabrication because the pattern line is used in a drying (heating) process for forming a fine pattern. The width varies with temperature and time (ΔCD (nano)). Further, when developing after forming the coating layer, the coating composition of the present invention uses an organic solvent (the same developer as the negative-tune developer can be used), and therefore, the low cost of coating the composition is due to the use of The developing device (unit) used in the pattern forming process without an additional developing device. Moreover, the coating composition of the present invention has a lighter than a negative tone or water The soluble polymer is more excellent in etching resistance.

The invention and its attendant advantages will be apparent from the following detailed description.

The coating composition for forming a fine pattern according to the present invention is formed by forming a coating layer onto the surface of the photoresist pattern formed by using a negative-tune developer to minimize the pattern size (forming a fine pattern) . The coating composition for forming a fine pattern comprises: a polymer of the following formula 1; and an organic solvent.

In Formula 1, R ₁ is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, preferably 2 to 15 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, preferably 4 to 15 One carbon atom, if desired, R ₁ may contain from 1 to 3 oxygen atoms. R ₂ , R ₃ and R ₅ are each a hydrogen atom or a methyl group, and "X" is a hydrocarbon group having 1 to 3 carbon atoms or is absent. If desired, "X" may contain 1 to 3 oxygen atoms. atom. R ₄ is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as one of the terminal groups of the polymer, and "a" is a mol% of the repeating unit, and is 100 mol% in the formula 1.

When R ₁ is a linear or branched hydrocarbon group, examples of R ₁ include methyl, methanol (-CH ₂ OH), ethyl, ethanol (-C ₂ H ₄ OH), n-propyl, isopropyl, n-Butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, 2-methylbutyl, n-hexyl, isohexyl, 2,3-dimethyl-2-butyl, n-heptyl , Zheng Xinji, Zheng Yiji and so on. When R ₁ is a cyclic hydrocarbon group, R ₁ may be a monocyclic or polycyclic alkyl or alkenyl group having 3 to 20 carbon atoms, a cyclic ester group or a cyclic ether group having 3 to 15 carbon atoms, Or an aromatic group having 4 to 15 carbon atoms or the like. Specific examples of the monocyclic or polycyclic alkyl group or alkenyl group include a cyclohexyl group, an adamantyl group, an octahydro-4,7-low methyl-fluorenyl group, an borneol group, a di-born borneol group and the like. Specific examples of the cyclic ester group or the cyclic ether group include a dihydrofuran-2-one group, a tetrahydro-piperidin-2-one group, Ind-2-keto group, 4- -Tricyclo[4.2.1.0 ^3,7 ]decane-5-one, 4,8-di -Tricyclo[4.2.1.0 ^3,7 ]decane-5-keto, 5- -Tricyclo[5.2.1.0 ^3,8 ]decane-4-keto, 5,9-di -Tricyclo[5.2.1.0 ^3,8 ]decane-4-keto, 7- -bicyclo[2.2.1]heptane and the like. Specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthracenyl group and the like. Therefore, R ₁ may be substituted as a substituent such as a hydroxyl group (-OH) or may include an ether group (-O-). Examples of "X" include a mercapto group (-CO-), an ester group (-COO-), an acetate group (-CH ₂ COO-), and the like. Examples of R ₄ include an amine, a second amine, a guanamine, an anthracene, and the like, and are preferably hydrazine.

Typical examples of the polymer of the formula 1 include the following polymers of the formulae 1a to 1p.

[Formula 1d]

[Formula 1j]

[Formula 1p]

In the formulae 1a to 1l , "a" is the mol% of the repeating unit constituting the polymer, where "a" is 100 mol%. In the formulae 1m to 1p, "a" and "b" are mol% of each repeating unit constituting the polymer, where "a" is 0 to 100 mol%, preferably 1 to 99 mol%, particularly preferably 50 to 95 mol%, and "b" is 0 to 100 mol%, preferably 1 to 99 mol%, particularly preferably 5 to 50 mol%.

The polymer of Formula 1 has a weight average molecular weight (Mw) of from 2,000 to 100,000, preferably from 3,000 to 50,000, particularly preferably from 5,000 to 15,000. When the weight average molecular weight of the polymer of Formula 1 is less than 2,000, the coating performance is poor during coating (difficulty in formation of a coating layer). When the weight average molecular weight of the polymer of Formula 1 is more than 100,000, the solubility in terms of an organic solvent may rapidly decrease. Further, the acidity (pH) of the polymer of Formula 1 may be from 7.0 to 8.5.

The polymer of Formula 1 is a brush-type, fat-soluble polymer having more than one nitrogen atom. When the polymer of Formula 1 is heated (80 to 180 ° C), the acid-base reaction is developed as a negative-tuning developer by using a deprotecting functional group on the surface of the resist pattern, and is passed through the photosensitive polymer on the surface of the pattern. A tie reaction forms a coating layer on the surface of the pattern. In other words, when a pattern-reducing substance (coating composition) having a polymer of nitrogen is coated on the photoresist pattern, the photoresist pattern and the overcoat layer may be crosslinked to form a single layer of the photoresist pattern. The fine pattern has a reduced size of the conventional photoresist pattern above it.

The organic solvent used in the coating composition for forming a fine pattern according to the present invention can be used without particular limitation, but the organic solvent forming the photoresist pattern is developed by a negatively tunable developer. An example of an organic solvent is one having 2 to 12 carbon atoms a hydrocarbon compound to 4 oxygen atoms. Specific examples of the organic solvent include alcohols having 2 to 8 carbon atoms (e.g., n-hexanol, n-heptanol, etc.), preferably 4 to 8 carbon atoms, particularly preferably 6 to 8 carbon atoms; and 2 to 12 carbon atoms. a carbon atom ether compound (for example, diisopropyl ether, diisobutyl ether, diisoamyl ether, etc.), preferably 4 to 12 carbon atoms, particularly preferably 6 to 10 carbon atoms; a ketone compound of 3 to 12 carbon atoms (e.g., methyl isobutyl ketone, etc.), preferably 4 to 12 carbon atoms, particularly preferably 6 to 10 carbon atoms; and 3 to 12 carbon atoms, An ester compound of 4 to 10 carbon atoms (e.g., n-butyl acetate which is a negative-tuning developer), a mixture thereof, and the like are preferable.

The content of the compound of the formula 1 is from 0.5 to 15% by weight, preferably from 3 to 10% by weight, particularly preferably from 3 to 8% by weight, relative to the entire coating composition for forming a fine pattern. When the content of the polymer is less than 0.5% by weight, the formation of the coating layer may be difficult, and when the content of the polymer is more than 15% by weight, the coating layer may be irregular. Further, the rest is the content of the organic solvent, except for the polymer of the formula 1.

Further, the coating composition for forming a fine pattern of the present invention may further contain an additive which is an acid catalyst, a surfactant, a basic compound, a mixture thereof and the like, if necessary. The acid catalyst is used to improve the degree of crosslinking or crosslinking rate of the coating layer when the coating layer is formed. Examples of the acid catalyst include hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, ethylsulfonic acid, propylsulfonic acid, butylsulfonic acid, benzenesulfonic acid, 2,4-dimethylbenzenesulfonic acid, p-toluenesulfonic acid. Acid (PTSA), camphorsulfonic acid, naphthylsulfonic acid, cyclohexylsulfonic acid, acetic acid, ethyl acetic acid, propylacetic acid, isopropylacetic acid, mixtures thereof and the like. If an acid catalyst is used, the acid catalyst is used in an amount of from 0.1 to 5 parts by weight, preferably from 0.5 to 3 parts by weight, based on 100 parts by weight of the entire coating composition for forming a fine pattern. When the content of the acid catalyst of the entire coating composition for forming a fine pattern is less than 0.1 part by weight relative to 100 parts by weight, the degree of crosslinking or crosslinking rate of the coating layer may be Improvement. When the content of the acid catalyst of the entire coating composition for forming a fine pattern is more than 5 parts by weight with respect to 100 parts by weight, the amount of crosslinking may rapidly increase due to excessive acid excess during formation of the coating layer. Catalytic effect.

The surfactant is used to improve the coating properties of the coating composition, and a conventional surfactant can be used. Examples of surfactants include anionic surfactants, cationic surfactants, amphiphilic surfactants, mixtures thereof, and the like, and the type of surfactant may vary depending on the size and thickness of the pattern. Specific examples of the surfactant include a surfactant mainly composed of an alkylbenzenesulfonate, a higher amine halide, a fourth ammonium salt-based surfactant, and an alkylpyridinium salt-based surfactant. A surfactant mainly composed of an amino acid, a surfactant mainly composed of sulfonimide, and the like. If a surfactant is used, the surfactant is contained in an amount of from 0.01 to 5 parts by weight, preferably from 0.1 to 1 part by weight, based on 100 parts by weight of the total coating composition for forming a fine pattern. When the content of the entire coating composition surfactant is less than 0.01 part by weight relative to 100 parts by weight, the coating layer may be irregular when the coating layer is formed. And when the content of the total coating composition surfactant is more than 5 parts by weight relative to 100 parts by weight, the coating layer may be formed due to the foam formed by the surfactant when the coating layer is formed Deterioration, or excessive surfactant during development by the coating layer, may lose the photoresist pattern.

The basic compound is used as a crosslinking agent and a stabilizer, and a conventional amine compound can be used. Examples of the basic compound include triethanolamine (TEOA), 2-aminoethanol, 2-(2-aminoethoxy)ethanol, and the like. The content of the basic compound is from 0.01 to 2 parts by weight, preferably from 0.05 to 1 part by weight, particularly preferably from 0.1 to 0.5 part, per 100 parts by weight of the entire coating composition for forming a fine pattern. weight ratio. When the content of the basic compound is less than 0.01 parts by weight relative to 100 parts by weight of the total coating composition When the effect of the basic compound is not obtained. And when the content of the basic compound of the entire coating composition is more than 2 parts by weight relative to 100 parts by weight, the surface of the photoresist pattern may be denatured when the coating layer is formed because the alkalinity of the coating composition is increased. .

The present invention also provides a method of using a coating composition to form a fine pattern of a semiconductor device, the method comprising the steps of: (a) forming a photoresist layer on a substrate to be etched; (b) using a predetermined exposure by exposure The photoresist layer of the masking and exposing device and developing the photoresist layer on the photoresist layer using a conventional negative-tuning developer such as n-butyl acetate to form a photoresist pattern; (c) forming the photoresist in the photoresist layer Coating the coating composition for forming a fine pattern; and (d) coating the photoresist pattern on the coating composition by heating and developing to form a coating layer.

The heating method of the step (d) forms a coating layer by crosslinking a photosensitive polymer having a composition and a surface of the photoresist pattern by crosslinking bonding. Here, the heating is carried out at 80 to 180 ° C, preferably at 110 to 150 ° C for 5 to 300 seconds, preferably 50 to 90 seconds. When the heating temperature is lower than 80 ° C or the heating time is less than 5 seconds, a coating layer (protective layer) may not be formed on the photoresist pattern. And, when the heating temperature exceeds 180 ° C or the heating time exceeds 300 seconds, the photoresist pattern may be melted. The method of forming a fine pattern can improve equipment utilization because no additional developing equipment is required, as opposed to using a coating composition containing a conventional water-soluble polymer.

In the following, preferred embodiments are provided for a more complete understanding of the present invention. The following examples are merely illustrative of the invention, and the invention is not limited by the following examples.

[Manufacturing Example 1] Preparation of Polymer of Formula 1a

Vinyl benzene (44.8 g, 0.5 mol, common name: styrene), 2,4-diphenyl-4-methyl-1-pentene (11.7 g, 0.05 mol, chain transfer agent) and 2,2"- Azoquinone [2-(2-imidazolin-2-yl)propane] (0.5 g, VA-061, Wako Co., Ltd.) was added The reaction was quenched at 80 ° C for 24 hours using a 500 mL reactor refluxed with nitrogen. After the reaction was completed, the reaction was washed three times with deionized water (150 mL). The reaction was slowly added dropwise to methanol for precipitation. After the reaction was precipitated, the precipitated reactant was dried in an oven to obtain a fat-soluble polymer of Formula 1a (29.1 g, yield: 65%). The weight average molecular weight (Mw) and the degree of polymerization dispersion (PD) of the obtained polymer were measured by gel permeation chromatography (GPC) (Mw = 9,250, PD = 1.45).

[Manufacturing Example 2] Preparation of Polymer of Formula 1b

Vinyl benzene (44.8 g, 0.5 mol, common name: styrene), 2,4-diphenyl-4-methyl-1-pentene (11.7 g, 0.05 mol, chain transfer agent) and 2,2"- Azoindole (2-amidinopropane) dihydrochloride (0.5 g) was added to a 500 mL reactor refluxed with nitrogen, and the reaction was polymerized at 80 ° C for 24 hours. After completion of the reaction, deionized water (150 mL) was used. The reaction was washed three times. The reaction was slowly added dropwise to methanol for precipitation. After the reaction was precipitated, the precipitated reaction was dried in an oven to obtain a fat-soluble polymer of the formula 1b (26.0 g, yield: 58 %). The weight average molecular weight (Mw) and the degree of polymerization dispersion (PD) of the obtained polymer were measured by gel permeation chromatography (GPC) (Mw = 7,500, PD = 1.37).

[Manufacturing Example 3] Preparation of Polymer of Formula 1c

Vinyl benzene (44.8 g, 0.5 mol), 2,4-diphenyl-4-methyl-1-pentene (11.7 g, 0.05 mol) and 2,2"-arsenazo [N-(2- Carboxyethyl)-2-methylpropane] (0.5 g) was added to a 500 mL reactor refluxed with nitrogen, and the reactant was polymerized at 80 ° C for 24 hours. After the reaction was completed, the temperature of the reactant was lowered to 0 ° C, and 1,2-Extended Ethylamine (1.0 g) was slowly added dropwise to the reaction while reacting for 1 hour. After the reaction was completed, the reaction was washed three times with deionized water (150 mL). Methanol was added for precipitation. After the reactants were precipitated, the precipitated reactant was dried in an oven to obtain a fat-soluble polymer of formula 1c (21.5 g, yield: 43%, Mw = 6,230, PD = 1.44).

[Manufacturing Example 4] Preparation of Polymer of Formula 1d

A fat-soluble polymer of the formula 1d (79.3 g) was obtained in the same manner as in Production Example 1 except that adamantyl-1-yl ether (103.0 g, 0.5 mol) was used instead of the vinylbenzene (yield: 77%). Mw = 10,640, PD = 1.51).

[Manufacturing Example 5] Preparation of Polymer of Formula 1e

A lipophilic polymer of formula 1e (63.8 g) was obtained in the same manner as in Production Example 2 except that adamantyl-1-ylether acrylate (103.0 g, 0.5 mol) was used instead of vinylbenzene (yield: 62%). Mw = 9,410, PD = 1.45).

[Manufacturing Example 6] Preparation of Formula 1f Polymer

A fat-soluble polymer of the formula 1f (55.6 g) was obtained in the same manner as in Production Example 3 except that the adamantyl-1-yl ether (103.0 g, 0.5 mol) was used instead of the vinylbenzene (yield: 54%). Mw = 6,650, PD = 1.50).

[Production Example 7] Preparation of Formula 1g Polymer

A liposoluble polymer of the formula 1g was obtained in the same manner as in Production Example 1, except that tricyclo [5.2.1.02,6]decane-8-yl methacrylate (110.2 g, 0.5 mol) was used instead of vinylbenzene. 74.9 g) (yield: 68%, Mw = 9,950, PD = 1.44).

[Production Example 8] Preparation of a polymer of the formula 1h

A liposoluble polymer of the formula 1h was obtained in the same manner as in Production Example 2 except that tricyclo[5.2.1.02,6]decane-8-yl (110.2 g, 0.5 mol) was used instead of vinylbenzene. 65.0 g) (yield: 59%, Mw = 9,630, PD = 1.35).

[Manufacturing Example 9] Preparation of Polymer of Formula 1i

A liposoluble polymer of the formula 1i was obtained in the same manner as in Production Example 3, except that tricyclo[5.2.1.02,6]decane-8-yl (110.2 g, 0.5 mol) was used instead of vinylbenzene. 67.2 g) (yield: 61%, Mw = 8,020, PD = 1.41).

[Manufacturing Example 10] Preparation of Polymer of Formula 1j

A fat-soluble polymer of the formula 1j (57.2 g) was obtained in the same manner as in Production Example 1 except that adamantyl-1-ethyl methacrylate (110.0 g, 0.5 mol) was used instead of the vinylbenzene (yield: 52). %, Mw = 8, 910, PD = 1.49).

[Production Example 11] Preparation of a polymer of the formula 1k

A fat-soluble polymer of the formula 1k (60.5 g) was obtained in the same manner as in Production Example 2 except that adamantyl-1-ylether methacrylate (110.0 g, 0.5 mol) was used instead of the vinylbenzene (yield: 55). %, Mw = 7,840, PD = 1.48).

[Production Example 12] Formula 1 l Preparation of polymer

Except that methacrylic acid adamantan-1 than ether (110.0g, 0.5mol) divinylbenzene Alternatively, in the same manner as in Production Example 3 1 l of liposoluble polymers of formula (53.9g) (Yield: 49%, Mw = 7,250, PD = 1.45).

[Production Example 13] Preparation of Formula 1m Polymer

In addition to vinyl benzene (22.4 g, 0.25 mol) and adamantyl yl methacrylate (55.0 g, 0.25 mol) instead of vinyl benzene (44.8 g, 0.5 mol), A 1 m fat-soluble polymer (39.5 g, "a" and "b", respectively, 50 mol%) was obtained in the same manner (yield: 52%, Mw = 9,110, PD = 1.44).

[Manufacturing Example 14] Preparation of Formula 1n Polymer

In addition to vinyl benzene (22.4 g, 0.25 mol) and adamantyl yl methacrylate (55.0 g, 0.25 mol) instead of vinyl benzene (44.8 g, 0.5 mol), The liposoluble polymer of the formula 1n (37.1 g, "a" and "b", respectively, 50 mol%) was obtained in the same manner (yield: 48%, Mw = 8,590, PD = 1.46).

[Manufacturing Example 15] Preparation of Formula 1o Polymer

In addition to the use of vinyl benzene (22.4g, 0.25mol) and gold methacrylate A fat-soluble polymer of the formula 1o (32.5 g, "a") was obtained in the same manner as in Production Example 3 except that the cycloalkan-1-yl ether (55.0 g, 0.25 mol) was used instead of the vinylbenzene (44.8 g, 0.5 mol). And "b" were 50 mol%) (yield: 42%, Mw = 9,040, PD = 1.51).

[Manufacturing Example 16] Preparation of Polymer of Formula 1a

In addition to using 2,2"-arsenazo [2-(2-imidazolin-2-yl)propane] (0.25 g) instead of 2,2"-arsenazo [2-(2-imidazolin-2-yl) A lipophilic polymer of Formula 1a (36.7 g) was obtained in the same manner as in Production Example 1 except that propane] (0.5 g) (yield: 82%, Mw = 14,750, PD = 1.61).

[Manufacturing Example 17] Preparation of Polymer of Formula 1a

In addition to using 2,2"-arsenazo [2-(2-imidazolin-2-yl)propane] (1.0 g) instead of 2,2"-arsenazo [2-(2-imidazolin-2-yl) A lipophilic polymer of Formula 1a (25.1 g) was obtained in the same manner as in Production Example 1 except that propane] (0.5 g) (yield: 56%, Mw = 6,120, PD = 1.35).

[Manufacturing Example 18] Preparation of Formula 1p Polymer

In addition to vinyl benzene (22.4 g, 0.25 mol) and tricyclo[5.2.1.02,6]decane-8-yl (55.0 g, 0.25 mol) instead of vinyl benzene (44.8 g, 0.5 mol) Further, a lip-soluble polymer of Formula 1p (37.1 g, "a" and "b", respectively, 50 mol%) was obtained in the same manner as in Production Example 2 (yield: 48%, Mw = 9,430, PD = 1.48).

[Examples 1-1 to 1-19 and Comparative Example 1] Preparation of a coating composition for forming a fine pattern

Depending on the composition of Table 1, the fat-soluble polymer prepared in Production Examples 1 to 18 or the water-soluble polymer of the following formula 2 (here, "a" is 70 mol%, "b" is 30 mol%) and fat-soluble or The water-soluble surfactant (FC-4430, 3M Co., Ltd.) is completely dissolved in a solvent (the fat-soluble polymer is dissolved in n-butyl acetate (nBA), water-soluble polymerization) The material was dissolved in deionized water and filtered through a 0.2 micron ingot filter to obtain a coating composition for forming a fine pattern.

[Examples 2-1 to 2-19 and Comparative Example 2] Forming and evaluating a fine pattern

ArF organic anti-reflective layer composition (Dark (DAC)-A125, Dongjin semichem Co., Ltd.) was coated on a silicon wafer, dried at a thickness of 33 nm and dried at 240 ° C (heating) )60 seconds. Here, a negative photoresist composition (DHA-HV100 (ArF photoresist), Dongjing Semiconductor Chemical Co., Ltd.) was applied to a thickness of 100 nm and soft-dried (heated) at 95 ° C for 60 seconds to form a photoresist layer. a crystal on which a photoresist layer is formed The circle was formed on the wafer by exposure using an ArF exposure apparatus (numerical aperture: 0.85, ASML-1200B, ASML Co., Ltd.) at 110 ° C. Heat for 60 seconds to amplify the acid generated during the exposure. After acid amplification, the wafer was immersed in a negatively tuned developer (n-butyl acetate) for 15 seconds to develop and form an elongated contact hole pattern with an X-axis of 74 nm for line width and 370 for line width. Nano. Next, three coating compositions prepared in Examples 1-1 to 1-19 and Comparative Example 1 were applied to the wafer, and a contact hole pattern was formed on the wafer, and at 110 ° C, 130, respectively. Dry (heat) at °C and 150 °C for 60 seconds. After drying (heating), the wafer was immersed in a negatively tunable developer (n-butyl acetate) for 15 seconds to develop and obtain a fine pattern, and the pore size (diameter) was reduced (Comparative Example 2 was immersed in deionized water for 60 seconds). The results are shown in Table 2 and Table 3 below.

As shown in Tables 2 and 3, when the coating composition for forming a fine pattern according to the present invention is used, the pattern diameter can be effectively reduced, and the rate of change of the pattern diameter with temperature is higher than that of the water-soluble polymer coating composition. (Comparative Example 1) Stability. More specifically, the amount of change in the X-axis and the Y-axis of the elongated contact hole pattern is uniform, respectively, as in the circular pattern.

[Examples 3-1 to 3-19 and Comparative Examples 3-1, 3-2] Etching resistance of a coating composition for forming a fine pattern

The various coating compositions prepared in Examples 1-1 to 1-19 and Comparative Example 1 were coated on a tantalum wafer having a thickness of 200 nm and dried (heated) at 110 ° C for 60 seconds. In order to establish the criteria for comparison and standard, the negative photoresist compositions (DHA-HV100 (ArF photoresist), Dongjing Semiconductor Chemical Co., Ltd.) used in Examples 2-1 to 2-19 and Comparative Example 2 were applied to The photoresist layer was soft baked (heated) on a silicon wafer at 95 ° C for 60 seconds to form a photoresist layer. The wafer on which the photoresist layer was formed was heated at 110 ° C for 60 seconds by using an ArF exposure apparatus (numerical aperture: 0.85, Esmer-1200B, Esmer) to amplify the acid generated during the exposure. And obtaining a negative-tune photoresist with a deprotection of 200 nm thickness. Each wafer was dry etched in the presence of a gas (O ₂ :Cl ₂ :Ar=1:4:20) using a dry etching apparatus (TCP-9600PTX, LAM Co., Ltd.) for 60 seconds, and the results are shown in Table 4 below ( In the etching rate, the etching variation of the photoresist is 1.00).

As shown in Table 4, when the coating composition for forming a fine pattern according to the present invention is used, the etching resistance associated with the photoresist shrinkage material or the negative tone photoresist can be improved under dry etching conditions. Therefore, when applying a coating composition for forming a fine pattern to a semiconductor manufacturing method requiring a fine pattern, the line width of the pattern with temperature can be reduced Degree (critical dimension) deviation, and can have high etch resistance.

Claims (10)

A coating composition for forming a fine pattern, comprising: a polymer of the following formula 1; and an organic solvent, In Formula 1, R ₁ is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, and R ₂ , R ₃ and R ₅ are each a hydrogen atom or a methyl group. "X" is a hydrocarbon group having 1 to 3 carbon atoms or is absent, and R ₄ is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as one end group of the polymer, and "a" is a composition The mol% of the repeating unit of the polymer, and 100 mol% in the formula 1. The coating composition for forming a fine pattern according to the first aspect of the invention, wherein the polymer of the formula 1 is selected from the group consisting of polymers of the following formulas 1a to 1p. [Formula 1c] [Formula 1i] [Formula 1o] Wherein "a" is mol% of the repeating unit constituting the polymer and 100 mol% in the formulae 1a to 11, and "a" and "b" are mol% of each repeating unit constituting the polymer, and "a" is 0 to 100 mol% in 1 m to 1 p, and "b" is 0 to 100 mol%. The coating composition for forming a fine pattern according to the first aspect of the invention, wherein the polymer of the formula 1 has a weight average molecular weight of 2,000 to 100,000. A coating composition for forming a fine pattern according to the first aspect of the invention, wherein the organic solvent is a hydrocarbon compound having 2 to 12 carbon atoms and 1 to 4 oxygen atoms. The coating composition for forming a fine pattern according to the fourth aspect of the invention, wherein the organic solvent is selected from the group consisting of an alcohol compound having 2 to 8 carbon atoms and an ether compound having 2 to 12 carbon atoms. a group consisting of a ketone compound having 3 to 12 carbon atoms, an ester compound having 3 to 12 carbon atoms, and a mixture thereof. The coating composition for forming a fine pattern according to claim 4, wherein the organic solvent is selected from the group consisting of n-butyl acetate, n-hexanol, n-heptanol, diisopropyl ether, and diisobutylene. A group of ethers, diisoamyl ethers, methyl isobutyl ketones, and mixtures thereof. The coating composition for forming a fine pattern according to the first aspect of the patent application, wherein the content of the polymer of the formula 1 is relative to the entire coating composition for forming the fine pattern. It is 0.5 to 15% by weight, and the content of the organic solvent is the same as the polymer of the formula 1. The coating composition for forming a fine pattern according to the first aspect of the invention, wherein the coating composition for forming a fine pattern further comprises an additive selected from the group consisting of an acid catalyst and a surfactant. a group consisting of a basic compound and a mixture thereof, and the acid catalyst is used in an amount of 0.1 to 5 parts by weight, based on 100 parts by weight of the total coating composition for forming a fine pattern, and relative to 100 The weight ratio of the coating composition for forming a fine pattern, the surfactant is used in an amount of 0.01 to 5 parts by weight, and the coating composition for forming a fine pattern is compared with 100 parts by weight. The basic compound is used in an amount of from 0.01 to 2 parts by weight. The coating composition for forming a fine pattern according to the eighth aspect of the invention, wherein the acid catalyst is selected from the group consisting of hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, ethylsulfonic acid. , propyl sulfonic acid, butyl sulfonic acid, benzene sulfonic acid, 2,4-dimethylbenzene sulfonic acid, p-toluene sulfonic acid, camphor sulfonic acid, naphthyl sulfonic acid, cyclohexyl sulfonic acid, acetic acid, ethyl acetate , propyl acetic acid, isopropyl acetic acid and mixtures thereof. A method of forming a fine pattern using a coating composition for forming a fine pattern, the method comprising the steps of: forming a photoresist layer on a substrate to be etched; exposing the photoresist layer and using negative tone development Developing the photoresist layer to form a photoresist pattern on the photoresist layer; coating the coating composition for forming a fine pattern on the formed photoresist pattern; and coating thereon by heating and developing Coating the photoresist pattern of the composition to form a coating layer, wherein the coating composition for forming a fine pattern comprises: a polymer of the following formula 1; and an organic solvent, In Formula 1, R ₁ is a linear or branched hydrocarbon group having 1 to 20 carbon atoms, or a cyclic hydrocarbon group having 3 to 20 carbon atoms, and R ₂ , R ₃ and R ₅ are each a hydrogen atom or a methyl group. "X" is a hydrocarbon group having 1 to 3 carbon atoms or is absent, and R ₄ is a hydrocarbon group having 1 to 10 carbon atoms and 1 to 5 nitrogen atoms as one end group of the polymer, and "a" is a composition The mol% of the repeating unit of the polymer, and 100 mol% in the formula 1.