KR20160012492A - Coating composition for forming fine patterns and mothod of forming fine patterns by using the same - Google Patents

Abstract

The present invention relates to a coating composition for forming fine patterns, which can be used for negative tone development photoresist in ArF immersion photoresist, and to a method for forming fine patterns using the same. The coating composition for forming fine patterns comprises a resin including any one first repeating unit selected from the group consisting of repeating units represented by chemical formula 1 to chemical formula 3 and combinations thereof. Chemical formula 1 to chemical formula 3 are the same as described in the detailed description of the present invention. The coating composition for forming fine patterns according to the present invention can form fine patterns smaller than 0.05 μm without a separate process of applying temperature and can achieve a significant improvement in the miniaturization and stability of a semiconductor device including various patterns by minimizing the structural defects of photoresist patterns such as top rounding, undercut, etc. occurring when forming fine patterns in a semiconductor manufacturing process.

Description

TECHNICAL FIELD [0001] The present invention relates to a coating composition for forming a fine pattern and a method for forming a fine pattern using the coating composition.

The present invention relates to a coating composition for forming a fine pattern which can be used for Negative Tone Development (hereinafter referred to as NTD) photoresist in an ArF Immersion photoresist (hereinafter referred to as "PR") and a fine pattern More particularly, the present invention relates to a method of forming fine patterns of less than 0.05 mu m without any additional step of applying a temperature, And to a method for forming a fine pattern using the same. 2. Description of the Related Art [0002] The present invention relates to a coating composition for forming a fine pattern, and a method for forming a fine pattern using the same, which can significantly reduce the size and stability of a semiconductor device including various patterns.

Development of various photoresists has been accelerated due to the high integration and high performance of semiconductor devices and the development of lithography processes. With such high integration and high performance, a chemically amplified photoresist corresponding to the miniaturization of the design rule has been developed together. However, the minimum resolution that can be implemented using the ArF exposure apparatus is about 0.05 μm. Therefore, it is difficult to form fine patterns for manufacturing integrated semiconductor devices, and various methods have been studied.

As a method of forming a fine pattern widely used up to now, there is a resist thermal reflow method which imparts fluidity by heat treatment at a high temperature. The resist thermal reflow method may reduce the size of the contact hole pattern by forming a contact hole pattern with a photoresist and then heat-treating the photoresist to a temperature higher than the glass transition temperature. However, according to this method, the top- -rounding phenomenon and an undercut phenomenon may occur, and it may be difficult to control the critical dimension.

Therefore, by coating a functional material on the entire surface of the formed photoresist contact hole and performing a heat treatment, a cross-linking reaction occurs at the interface between the functional material and the photoresist contact hole, and as a result, a technique of reducing the size of the contact hole pattern is important . In addition, when the patterning process for patterning by the etching using the photoresist pattern coated with the functional material is carried out, it must have a property to withstand the etching gas sufficiently.

Therefore, the functional material should satisfy the following requirements.

First, when the functional material is coated on the entire surface of the formed photoresist contact hole, the functional material must be water-soluble since it should not affect the photoresist film and the contact hole pattern and have no reactivity.

Second, a functional material is coated on the entire surface of the formed photoresist contact hole and a heat treatment is performed, so that a cross-linking reaction is required at the interface between the functional material and the photoresist contact hole.

Third, the functional material that has not undergone the crosslinking reaction at a portion other than the interface with the photoresist contact hole should be removed with a water-soluble solvent.

Fourth, since the etching process must be performed using the photoresist pattern coated with the functional material, the resist pattern must be excellent in resistance to etching gas.

On the other hand, a method of reducing the pattern size by using functional materials in the formed photoresist contact hole pattern is used, but there is a problem that the process must be repeated several times in order to obtain a sufficiently small contact hole pattern. In addition, since the functional material does not contain an aromatic structure or a bulky portion, there is a problem that etching resistance is weak when patterning a photoresist pattern coated with a functional material. Furthermore, the above method has a problem that the coating performance against the contact hole pattern, which is becoming increasingly integrated and refined, is insufficient, and the thickness to be crosslinked can not be uniformly controlled according to the heating temperature in the heating process.

U.S. Patent Publication No. 2013/0107235 (Disclosure Date: May 2, 2013) Korean Patent Publication No. 2013-0074831 (published on July 5, 2013)

It is an object of the present invention to provide a semiconductor device which can form a fine pattern of less than 0.05 mu m without the need of applying a separate temperature and minimizes structural defects of the photoresist pattern such as top rounding and undercut, And to provide a coating composition for fine pattern formation which can significantly increase the size and stability of a semiconductor device including patterns.

Another object of the present invention is to provide a method of forming a fine pattern capable of stably and efficiently forming a fine photoresist pattern.

In order to achieve the above object, a coating composition for forming a fine pattern according to an embodiment of the present invention is coated on a photoresist pattern to reduce a distance between patterns, And a resin containing any one of the first repeating units selected from the group consisting of combinations thereof.

[Chemical Formula 1]

(2)

(3)

The resin may further comprise a second repeating unit selected from the group consisting of repeating units represented by the following formulas (4) and (5), and combinations thereof.

[Chemical Formula 4]

[Chemical Formula 5]

(In the formula (4), n ₁ is an integer of 0 to 5)

The resin may include the first repeating unit and the second repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01.

The resin may further comprise a third repeating unit selected from the group consisting of repeating units represented by the following formulas (6) and (7), and combinations thereof.

[Chemical Formula 6]

(7)

(In the formulas (6) and (7), each of n ₂ is independently an integer of 0 to 5)

The resin may include the first repeating unit and the third repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01.

 The resin may be any one selected from the group consisting of compounds represented by the following formulas (8-1) to (8-24).

[Chemical Formulas 8-1 to 8-24]

(In the formulas (8-1) to (8-24)

Wherein n ₁ to n ₂ are each independently an integer from 0 to 5, wherein l is a real number of 0.01 <l≤1, wherein m is a real number of 0≤m <0.99, and n is the 0≤n <0.99 And l, m and n satisfy 1 + m = 1 or 1 + m + n = 1,

The coating composition for forming a fine pattern may further comprise a water-soluble solvent comprising 100 parts by weight of water and 1 to 20 parts by weight of an alcohol.

The coating composition for fine pattern formation may include 100 parts by weight of the water-soluble solvent and 0.01 to 15 parts by weight of the resin.

The alcohol may be an alkoxy alcohol.

The method for forming a fine pattern according to another embodiment of the present invention includes the steps of forming a photoresist pattern and coating the coating composition for forming a fine pattern according to the first claim on the photoresist pattern.

The step of coating the coating composition for fine pattern formation may be performed at a temperature lower than 100 ° C.

Other details of the embodiments of the present invention are included in the following detailed description.

The coating composition for forming a fine pattern according to an embodiment of the present invention can form a fine pattern of less than 0.05 탆 without a separate process of applying a temperature and can be used for forming a top pattern, By minimizing the structural defects of the photoresist pattern, miniaturization and stability of semiconductor devices including various patterns can be remarkably increased.

According to the method for forming a fine pattern according to an embodiment of the present invention, a fine photoresist pattern can be stably and efficiently formed.

1 is a cross-sectional view illustrating a coating layer formed using a coating composition for forming a fine pattern according to an embodiment of the present invention.
2 is a schematic diagram showing an NTD photoresist in a non-exposed region.
3 is a schematic diagram showing an NTD photoresist in an exposed region.
4 is a schematic view showing a salt formed by a resin and an NTD photoresist of a coating composition for forming a fine pattern of the present invention.

The present invention is capable of various modifications and various embodiments and is intended to illustrate and describe the specific embodiments in detail. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the specification of the present invention, a photoresist pattern means that a plurality of grooves of a predetermined shape are regularly or irregularly formed in the photoresist layer. The shape of the groove may be a line shape or a hole shape, but the present invention is not limited thereto. Further, the fine photoresist pattern means that the width of the groove forming the pattern is narrower, the width of the groove in the hole pattern is the diameter of the hole, the width of the groove in the line pattern is the width of the line . Specifically, the fine photoresist pattern may have a ratio of the interval to the adjacent groove to the width of the groove, preferably not more than 1, particularly preferably not more than 0.9, more preferably not more than 0.8, May be substantially 0.5 or more.

The coating composition for forming a fine pattern according to an embodiment of the present invention is a coating composition for forming a fine pattern which is coated on a photoresist pattern to reduce a distance between patterns.

1 is a cross-sectional view illustrating a coating layer formed using a coating composition for forming a fine pattern according to an embodiment of the present invention. Referring to FIG. 1, a coating layer 130 is formed on the surface of a photoresist pattern 120 formed on a substrate 110 using the coating composition for forming a fine pattern. The width of the photoresist pattern 120 is reduced by the coating layer 130 to form a finer pattern.

In particular, the coating composition for forming a fine pattern of the present invention is a coating composition for forming a fine pattern which can be used for a negative tone development photoresist, and is used in a conventional positive tone development (PTD) type photoresist Although there are many coating compositions for forming fine patterns, many coating compositions for forming fine patterns used for NTD photoresists are not invented much.

The present invention is based on the fact that not only the coating composition for forming a fine pattern used for the NTD has all the requirements required for the coating composition for forming a fine pattern but also the conventional coating composition for forming a fine pattern is coated with a photoresist While the coating composition for fine pattern formation of the present invention has an effect of reducing the pattern by cross-linking between the coating compositions for fine pattern formation, the coating composition for fine pattern formation of the present invention can be applied at room temperature, This is possible. This is because the coating composition for forming a fine pattern of the present invention does not cross-link with the NTD photoresist but forms a salt.

In the case of the coating composition for forming a fine pattern of the present invention, the temperature can be applied to the photoresist for NTD by applying the temperature. In this case, the degree of pattern reduction can be controlled by changing the temperature at 100 ° C or less.

FIG. 2 is a schematic view showing an NTD photoresist in an unexposed area, and FIG. 3 is a schematic diagram showing an NTD photoresist in an exposed area. Referring to FIGS. 2 and 3, in the NTD photoresist in the exposed region, a carboxylic acid is generated at a site where an acid labile group is deacidified by an acid, and a carboxylic acid The NTD photoresist in the exposed region is insoluble in the organic solvent and does not dissolve in the developer, and forms a pattern.

The coating composition for forming a fine pattern of the present invention includes a resin containing any one of the first repeating units selected from the group consisting of repeating units represented by the following formulas (1) to (3) and combinations thereof.

[Chemical Formula 1]

(2)

(3)

As the resin contains an amine group, salt formation with NTD photoresist is possible at room temperature. 4 is a schematic view showing a salt formed by a resin and an NTD photoresist of a coating composition for forming a fine pattern of the present invention. Referring to FIG. 4, the NTD photoresist includes an amine group and a salt contained in the resin of the coating composition for forming a fine pattern, wherein the exposed region remains as a pattern and includes a carboxylic acid in a chemical structure. It can be coated at room temperature.

In addition, the resin containing any one of the repeating units selected from the group consisting of the repeating units represented by formulas (1) to (3) and combinations thereof must be dissolved in water to remove the resin remaining after coating, Since it is necessary to dissolve the patterned NTD photoresist such as n-butyl acetate or the like which is mainly used as a developer for dissolution in a solvent which does not have the property of dissolving the repeating units represented by the following formulas 4 and 5, And a second repeating unit selected from the group consisting of a combination of the first repeating unit and the second repeating unit. That is, the second repeating unit includes an amide group.

[Chemical Formula 4]

[Chemical Formula 5]

In Formula 4, n ₁ is an integer of 0 to 5, preferably 1 or 2.

The resin may contain the first repeating unit and the second repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01, preferably 0.2: 0.8 to 0.99: 0.01, Preferably in a molar ratio of 0.3: 0.7 to 0.5: 0.5.

When the molar ratio of the first repeating unit is out of the above range, more than 30% of carboxylic acid is used in the first patterned NTD PR when used for NTD patterning. In this case, Critical Dimension, hereinafter referred to as CD) may not be reduced.

If the molar ratio of the second repeating unit is less than 0.01, the effect of including the second repeating unit is insignificant. If the molar ratio is more than 0.99, the solubility in a solvent that does not affect water solubility or NTD PR may be poor.

The resin may further comprise a third repeating unit selected from the group consisting of repeating units represented by the following formulas (6) and (7), and combinations thereof.

[Chemical Formula 6]

(7)

In the general formulas (6) and (7), n ₂ is each independently an integer of 0 to 5, preferably 1 or 2.

When the resin further includes the third repeating unit, solubility in an organic solvent that is not water-soluble may be improved.

The resin may contain the first repeating unit and the third repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01, preferably 0.2: 0.8 to 0.99: 0.01, Preferably in a molar ratio of 0.3: 0.7 to 0.5: 0.5.

When the molar ratio of the first repeating unit is out of the above range, more than 30% of carboxylic acid is used in the first patterned NTD PR when used for NTD patterning. In this case, Critical Dimension, hereinafter referred to as CD) may not be reduced.

When the molar ratio of the third repeating unit is less than 0.01, the effect of including the third repeating unit is insignificant, and when it exceeds 0.99, the solubility in a water-soluble solvent may be poor.

Specifically, the resin may be any one selected from the group consisting of compounds represented by the following formulas (8-1) to (8-24).

[Chemical Formulas 8-1 to 8-24]

In the general formulas (8-1) to (8-24), n ₁ to n ₂ are each independently an integer of 0 to 5, 1 is a real number of 0.01 <1, and m is 0 <m <0.99 M and n satisfy a condition of 1 + m = 1 or 1 + m + n = 1, where n is a real number of 0? N <0.99.

The compounds represented by the above general formulas (8-1) to (8-24) may be block copolymers, random copolymers or graft copolymers. The polymerization of the above compounds can be carried out by conventional methods such as bulk polymerization, solution polymerization, suspension polymerization, bulk suspension polymerization, emulsion polymerization, radical polymerization and the like.

However, when the radical polymerization method is used, initiators for radical polymerization include azobisisobutyronitrile (AIBN), benzoyl peroxide (BPO), lauryl peroxide, azobisisobaronitrile, azobisisobalononitrile , T-butyl hydroperoxide, and the like can be used, but the kind of the radical polymerization initiator is not particularly limited in the present invention.

As the polymerization solvent, benzene, toluene, xylene, halogenated benzene, diethyl ether, tetrahydrofuran, esters, ethers, lactones, ketones, amides and alcohols can be used. Or may be used as two or more mixed solvents.

The temperature of the polymerization may be appropriately selected depending on the kind of the catalyst, and unreacted monomers and by-products remaining in the reaction mixture after the completion of the polymerization may be removed by a precipitation method using a solvent.

The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") of the resin by gel permeation chromatography (GPC) may be from 2,000 to 1,000,000 g / mol, and preferably from 3,000 to 50,000 g / mol. The molecular weight distribution of the resin may be 1.0 to 5.0, preferably 1.0 to 3.0. The molecular weight distribution of the resin can be appropriately controlled by changing the amount of the polymerization initiator used and the reaction time.

The coating composition for fine pattern formation may comprise 100 parts by weight of a water-soluble solvent and 0.01 to 15 parts by weight of the resin. If the content of the resin is less than 0.01 part by weight, the coating property may be lowered to form the coating layer 130 insufficiently. If the content of the resin is more than 15 parts by weight, uniformity of the coating may be lowered.

As the water-soluble solvent, a mixture of alcohol and water may be used. As the alcohol, C1-C10 alkyl alcohol or C1-C10 alkoxy alcohol can be preferably used. The alcohol contained in the water-soluble solvent may be used in an amount of 1 to 20 parts by weight based on 100 parts by weight of the water. If the content of the alcohol is less than 1 part by weight, the effect of promoting dissolution may be deteriorated. If the content of the alcohol is more than 20 parts by weight, it may be difficult to form a uniform coating film.

Examples of the alcohols include alcohols such as methanol, ethanol, propanol, isopropanol, n-butanol, see-butanol, t-butanol, Alkyl alcohols, and alkoxy such as 2-methoxyethanol, 2- (2-methoxyethoxy) ethanol, 1-methoxy-2-propanol and 3-methoxy- Based alcohol. The alcohols may be used alone or in combination of two or more.

The method for forming a fine pattern according to another embodiment of the present invention includes forming a photoresist pattern and coating the coating composition for forming a fine pattern according to an embodiment of the present invention on the photoresist pattern 120 .

The method for forming the photoresist pattern 120 may be any conventionally used method, and is not particularly limited in the present invention. However, the composition for forming the photoresist pattern 120 includes a solvent together with the photoresist polymer.

Specific examples of the photoresist polymer include (meth) acrylic acid ester polymer, (? -Trifluoromethyl) acrylic acid ester-maleic anhydride copolymer, cycloolefin-maleic anhydride copolymer, polynorbornene, cycloolefin A polymer compound obtained by a ring-opening metathesis reaction, a polymer compound obtained by hydrogenating a polymer obtained by a ring-opening metathesis reaction of cycloolefin, a hydroxystyrene and a (meth) acrylic ester derivative, styrene, vinylnaphthalene, vinyl anthracene, vinyl pyrene, There may be used those selected from the group consisting of a polymer compound obtained by copolymerizing any of novolac, novolac, novolac, novolac, novolac, novolac, novolac, novolac, .

The photoresist polymer may be contained in an amount of 3 to 20% by weight based on the total weight of the composition for forming a photoresist pattern. If the content of the photoresist polymer is less than 3% by weight, the viscosity of the composition becomes too low to form a film having a desired thickness, and pattern loss is increased by a relatively large amount of photoacid generator And if it exceeds 20% by weight, the film thickness becomes too thick, so that the transmittance of the radiation becomes poor and it is difficult to obtain a vertical pattern.

Further, in order to obtain a uniform and flat photoresist coating film, it is preferable to dissolve the polymer and the acid generator in a solvent having an appropriate evaporation rate and viscosity.

Examples of the usable solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene Esters such as glycol monopropyl ether acetate; Ketones such as methyl isopropyl ketone, cyclohexanone, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, 2-heptanone, ethyl lactate and gamma-butyrolactone. A single species or a mixture of two or more species may be used.

In addition, the amount of the solvent to be used can be appropriately controlled depending on the physical properties of the solvent, such as volatility, viscosity, etc., so that a uniform resist film can be formed.

The acid generator may be a photoacid generator (hereinafter referred to as PAG), which is an onium salt based iodonium salt, a sulfonium salt, a phosphonium salt, a diazonium salt, a pyridinium salt , Imide or the like can be used, and triphenylsulfonium nonaplate can be preferably used.

The acid generator may be included in an amount of 0.3 to 15 parts by weight, preferably 0.5 to 10 parts by weight, and more preferably 2 to 10 parts by weight based on 100 parts by weight of the solid content of the photoresist polymer. When the content of the acid generator is more than 15 parts by weight, the perpendicularity of the pattern is significantly lowered. When the content of the acid generator is less than 0.3 parts by weight, the flexibility of the pattern may be lowered.

 The composition for forming a photoresist pattern may further contain an additive depending on the purpose such as improving the coating property. As the additive, any additive that is usually used in a composition for forming a photoresist pattern can be used without any particular limitation. Specific examples thereof include an alkali dissolution inhibitor, an acid diffusion inhibitor, and a surfactant. Mixtures of more than two species may be used.

The method for forming a photoresist pattern using the composition for forming a photoresist pattern includes the steps of forming a resist film by applying the photoresist pattern forming composition onto a substrate 110, Exposing the resist pattern to a predetermined pattern, and developing the exposed resist pattern.

As the substrate 110, a wafer substrate can be used. As a method of applying the substrate 110, a spin coating method, a flow coating method, or a roll coating method can be used.

Specifically, it is coated on a substrate 110 such as a silicon wafer so as to have a film thickness of 0.3 to 2.0 탆, prebaked at 60 to 150 캜 for 1 to 10 minutes, preferably at 80 to 130 캜 for 1 to 5 minutes do.

Subsequently, the photoresist film is partially irradiated with radiation to form a fine pattern. The radiation usable here is not particularly limited, but an ultraviolet ray, an ultraviolet ray, a KrF excimer laser, an ArF excimer laser, an F2 excimer laser, an X-ray and an electron beam as a charged particle ray can be used. And can be appropriately selected depending on the kind.

Specifically, after irradiating the substrate with radiation such that the energy is about 1 to 200 mJ / cm 2, preferably about 10 to 100 mJ / cm 2 at the time of exposure, it is irradiated at 60 to 150 ° C for 1 to 5 minutes, preferably at 80 to 130 ° C, Post-exposure bake (PEB) for 3 minutes.

The resist pattern exposed after the exposure process is developed by a conventional method such as a dip method, a puddle method or a spray method for 0.1 to 3 minutes, preferably 0.5 to 2 minutes, 110 to form a desired pattern.

At this time, the developer can be used without any particular limitation as long as it is usually used as a negative tone developer. Specific examples of the solvent include ketone solvents (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, and acetylacetone), ester solvents (e.g., methyl acetate, n-butyl acetate, propylene glycol monomethyl ether acetate, (N-methyl-pyrrolidone, N, N-dimethylformamide and the like), ether-based solvents (e.g., methyl ethyl ketone, methyl formate, ethyl lactate), alcohol solvents (methyl alcohol, ethylene glycol, ethylene glycol monomethyl ether, An organic developing solution such as a polar solvent such as a solvent (dioxane, tetrahydrofuran, etc.) or a hydrocarbon solvent (for example, toluene, xylene, pentane or hexane) may be used. It can also be mixed with water. Of these, n-butyl acetate is preferred. At this time, the developer may further contain a surfactant if necessary.

On the other hand, the coating composition for forming a fine pattern can be formed by simply applying the coating composition on the photoresist pattern 120 and drying the coating composition. The coating composition for fine pattern formation may be applied by a conventional coating method. For example, the coating composition for fine pattern formation may be prepared and filtered, and then the filtered composition may be applied by spin coating, The photoresist pattern 120 may be formed on the surface of the photoresist pattern 120.

At this time, the coating may be performed at a temperature of 1 to 50 ° C without any additional heat treatment, and may be performed at room temperature. This is because, as described above, the resin of the coating composition for fine pattern formation contains the repeating units represented by the above formulas (1) to (3).

In this case, the thickness of the coating layer can be controlled by changing the temperature at 100 ° C or lower, and the thickness of the coating layer can be adjusted to adjust the thickness of the photoresist pattern 120 Or the size of the contact hole can be adjusted.

On the other hand, the coating composition for forming a fine pattern remaining after the coating layer is formed can be easily removed by washing with a water-soluble solvent such as water.

Hereinafter, the coating composition for fine pattern formation of the present invention will be described in more detail with specific examples. However, the technical idea of the present invention is not limited by the following embodiments.

[ Manufacturing example  1: Preparation of resin for coating]

(Resin for coating Synthetic example  1-1)

26 g of N- (3-Dimethylaminoethyl) -2-methyl-acrylamide and 24 g of arylamine [Allylamine] were dissolved in propylene glycol methyl ether Propylene glycol methyl ether (1-methoxy propanol] (168 g) was added to a solution prepared by dissolving dimethyl azobis butyronitrile (DMAB) (7 g) as an initiator and The temperature of the circulator was gradually raised to 75 ° C. and the temperature of the reactor was gradually raised, followed by stirring at 75 ° C. for 8 hours. When the reaction was completed, the resulting reaction solution Was added dropwise to 2.1 L of acetone and precipitated. The precipitate was filtered and vacuum dried to obtain a resin represented by the formula 8-1 (n ₁ = 3). The polystyrene reduced weight average molecular weight 6,500 g / mol.

¹ H NMR (CDCl _3, internal standard: tetramethylsilane): 0.96 ~ 1.59 (br, 8H), 2.4 (d, 2H), 2.0 ~ 2.3 (br, 8H), 2.6 ~ 2.7 (br, 4H), 3.3 (m, 2H, &lt; RTI ID = 0.0 &gt; 8 (br,

(Resin for coating Synthetic example  1-2)

, 50 g of N- (3-Dimethylaminopropyl) -2-methyl-acrylamide and 8 g of allylamine (8 g) were dissolved in propylene glycol methyl ether (154 g) was added to a jacket reactor together with dimethyl azobis butyronitrile (DMAB) (5 g) as an initiator, and the resulting solution was added to a jacket reactor The temperature of the circulator was set to 75 ° C., the temperature of the reactor was gradually increased, and the mixture was stirred for 8 hours at 75 ° C. After completion of the reaction, the resulting reaction solution was added to 2.2 L of acetone After precipitation by dropwise addition, the precipitate was filtered and dried in vacuo to obtain a resin represented by the formula 8-1 (n ₁ = 2). The weight average molecular weight of the resin in terms of polystyrene was 7,800 g / mol.

¹ H NMR (CDCl _3, internal standard: tetramethylsilane): 0.90 ~ 1.53 (br, 8H), 1.65 (br, 2H), 2.4 (d, 2H), 2.0 ~ 2.3 (br, 8H), 2.5 ~ 2.7 (br, 4 [Eta]), 3.2 (m, 2H, 8.5 (br, IH)

(Resin for coating Synthetic example  1-3)

50 g of N- (2-hydroxy-ethyl) -acrylamide and 7 g of allylamine were dissolved in propylene glycol methyl ether (1-methoxy-2 Propanol glycol methyl ether (1-methoxypropanol) (170 g) was added to a jacket reactor (5 g) together with dimethyl azobis butyronitrile (DMAB) The temperature of the circulator was raised to 75 ° C. and the temperature of the reactor was gradually raised and stirred for 8 hours at 75 ° C. After completion of the reaction, the resulting reaction solution was dissolved in acetone (Acetone) 2.3 L, and the precipitate was filtered and dried under vacuum to obtain a resin represented by the following formula (8-3). The weight average molecular weight of the resin in terms of polystyrene was 8,100 g / mol.

¹ H NMR (CDCl _3, internal standard: tetramethylsilane): 0.95 ~ 1.35 (br, 6H), 2.3 (d, 2H), 2.0 (br, 1H), 3.4 (m, 2H), 3.8 (br, 2H ), 8.2 (br, 1 H))

(Resin for coating Synthetic example  1-4 to 1-15 and comparison Synthetic example  1-1 to 1-2)

A resin was prepared in the same manner as in Resin Synthesis Example 1-1 except that the monomer for the coating resin Synthesis Example 1-1 was changed as shown in Table 1 below.

The Monomer 1
(Content, g) Monomer 2
(Content, g) Monomer 3
(Content, g) Synthetic example
1-1 The
8-1 Arylamine
(24) N- (3-dimethylaminoethyl) -2-methylacrylamide (26) - Synthetic example
1-2 The
8-1 Arylamine
(8) N- (3-dimethylaminopropyl) -2-methylacrylamide (50) - Synthetic example
1-3 The
8-3 Arylamine
(7) - N- (2-hydroxy-ethyl) -acrylamide (50) Synthetic example
1-4 The
8-2 Arylamine
(20) Methyl acrylamide (25) - Synthetic example
1-5 The
8-4 Arylamine
(10) - N- (2-ethyl) -acrylamide (17) Synthetic example
1-6 The
8-5 Allylcyclopentylamine (20) N- (3-dimethylaminoethyl) -2-methylacrylamide (25) - Synthetic example
1-7 The
8-7 Allylcyclopentylamine (20) - N- (2-hydroxy-ethyl) -acrylamide (18) Synthetic example
1-8 The
8-9 Allylcyclohexylamine (20) N- (3-dimethylaminoethyl) -2-methylacrylamide (22) - Synthetic example
1-9 The
8-11 Allylcyclohexylamine (20) - N- (2-hydroxy-ethyl) -acrylamide (19) Synthetic example
1-10 The
8-13 Arylamine
(10) N- (3-dimethylaminoethyl) -2-methylacrylamide (32) N- (2-hydroxy-ethyl) -acrylamide (25) Synthetic example
1-11 The
8-14 Arylamine
(10) N- (3-dimethylaminoethyl) -2-methylacrylamide (32) N- (2-ethyl) -acrylamide (20) Synthetic example
1-12 The
8-15 Arylamine
(10) Methyl acrylamide (19) N- (2-hydroxy-ethyl) -acrylamide (25) Synthetic example
1-13 The
8-16 Arylamine
(10) Methyl acrylamide (19) N- (2-ethyl) -acrylamide (21) Synthetic example
1-14 The
8-17 Allylcyclopentylamine (20) N- (3-dimethylaminoethyl) -2-methylacrylamide (25) N- (2-hydroxy-ethyl) -acrylamide (20) Synthetic example
1-15 The
8-21 Allylcyclohexylamine (20) N- (3-dimethylaminoethyl) -2-methylacrylamide (22) N- (2-hydroxy-ethyl) -acrylamide (14) Comparative Synthetic Example
1-1 - - N- (3-dimethylaminoethyl) -2-methylacrylamide (25) N- (2-hydroxy-ethyl) -acrylamide (20) Comparative Synthetic Example
1-2 - - Methyl acrylamide (19) N- (2-hydroxy-ethyl) -acrylamide (25)

[ Manufacturing example  2: Photoresist  Preparation of polymer]

As the polymerization monomer, 26 g of ethyl adamantine methacylate, 19.2 g of gamma-butyrolactone methacrylate, 26.2 g of hydroxy adamantane methacrylate, And 4 g of dimethyl azobisisobutylate as a polymerization initiator were placed in a flask together with 200 g of 1,4-dioxane, and then the inside of the flask was replaced with nitrogen with nitrogen gas and the temperature inside the reactor was raised to 70 ° C . The reaction was carried out at the same temperature for 5 hours. After completion of the polymerization reaction, the resultant reaction solution was cooled to room temperature. Excess nucleic acid was added to the cooled reaction solution to precipitate the precipitate, which was separated by filtration. The separated filtrate was washed with the same solvent and dried under reduced pressure to obtain 53 g of a random copolymer of the following formula (V). The polystyrene reduced weight average molecular weight (Mw) of the obtained copolymer was 7840 g / mol, and the ratio of the weight average molecular weight to the number average molecular weight was Mw / Mn = 1.93.

(V)

(V)

At this time, the molar ratios of the respective repeating units were l = 0.5, m = 0.3, and n = 0.2.

[ Manufacturing example  3: Contact hole  Pattern formation]

To 100 parts by weight of the photoresist resin obtained in Preparation Example 2, 2.5 parts by weight of triphenylsulfonium nonaplate as acid generator and 0.75 part by weight of tetramethylammonium hydroxide as basic additive were added to 1,000 parts by weight of propylene glycol methyl ether acetate And then a 0.2 mu m-thick coating film was formed. The resulting photoresist solution was applied to a substrate 110 using a spinner and dried at 110 DEG C for 60 seconds to form a film having a thickness of 0.2 mu m. The formed film was exposed using an ArF excimer laser stepper (lens numerical aperture: 0.78), and then heat-treated at 110 ° C for 60 seconds. Subsequently, the substrate was developed, washed and dried using n-butyl acetate for 40 seconds to form a negative contact hole pattern. The contact hole pattern size was measured with a Scanning Electron Microscope and the contact hole pattern was 120 nm in size.

[ Example  1: Preparation of coating composition for fine pattern formation and formation of coating layer]

( Example  1-1)

3.0 g of the resin obtained in Synthesis Example 1-1 for coating was sufficiently dissolved in a mixed solvent of 95.0 g of distilled water and 5.0 g of isopropyl alcohol and then filtered through a 0.2 탆 membrane filter to obtain a coating composition for forming a fine pattern .

The coating composition for forming a fine pattern was spin-coated on the wafer having the contact hole pattern formed in Preparation Example 3 at room temperature (20 캜) to form a coating layer. Subsequently, the coating composition was rinsed with deionized water for 60 seconds and rotated to remove the remaining coating composition for forming a fine pattern. Thereafter, the contact hole pattern size was measured with a scanning electron microscope, and the results are shown in Table 2 below.

( Example  1-2 to 1-15 and comparison Example  1-1 to 1-2)

The coating resin Resin Synthesis Examples 1-2 to 1-15 and Comparative Synthetic Synthetic Examples 1-1 to 1 were prepared in the same manner as in the above-mentioned Example 1-1, -2 was used in place of the coating solution prepared in Example 1-1.

Likewise, the contact hole pattern size was measured with a scanning electron microscope and the results are shown in Table 2 below.

Suzy Size (nm) of the contact hole before formation of the coating layer The size (nm) of the contact hole after formation of the coating layer Reduced Size (nm) Example 1-1 Resin Synthesis Example 1-1 121 134 13 Examples 1-2 Resin Synthesis Example 1-2 120 136 16 Example 1-3 Resin Synthesis Example 1-3 122 136 14 Examples 1-4 Resin Synthesis Example 1-4 121 142 21 Examples 1-5 Resin Synthesis Example 1-5 122 142 20 Examples 1-6 Resin Synthesis Example 1-6 120 134 14 Examples 1-7 Resin Synthesis Example 1-7 121 132 11 Examples 1-8 Resin Synthesis Example 1-8 121 134 13 Examples 1-9 Resin Synthesis Example 1-9 120 135 15 Example 1-10 Resin Synthesis Example 1-10 122 140 18 Example 1-11 Resin Synthesis Example 1-11 123 138 15 Examples 1-12 Resin Synthesis Example 1-12 121 139 18 Examples 1-13 Resin Synthesis Example 1-13 122 140 18 Examples 1-14 Resin Synthesis Example 1-14 124 138 14 Examples 1-15 Resin Synthesis Example 1-15 120 140 20 Comparative Example 1-1 Comparative Synthesis Example 1-1 121 121 0 Comparative Example 1-2 Comparative Synthesis Example 1-2 122 122 0

Referring to Table 2, in Comparative Examples 1-1 and 1-2, there was no difference in the size of the contact holes before and after the coating layer formation. In the case of Comparative Examples 1-1 and 1-2, the coating layer was formed at room temperature This is because the coating layer is not formed.

On the other hand, in the case of Examples 1-1 to 1-15, it can be seen that even if a coating layer is formed at room temperature, a coating layer is formed and the size of the contact hole can be reduced.

[ Example  2: Control of thickness of coating layer according to coating layer formation temperature]

( Example  2-1 to 2-5)

A coating layer was formed in the same manner as in Example 1-1, except that the coating layer forming temperature in Example 1-1 was changed as shown in Table 3 below.

The size of the formed contact hole pattern was measured with a scanning electron microscope, and the results are shown in Table 3 below.

( Comparative Example  2-1 to 2-2)

Comparative Example 1-1 was repeated except that the coating layer was heat-treated at a temperature of 150 ° C or higher for 60 seconds while changing the temperature as shown in Table 3 below to proceed the crosslinking reaction between the resin and the NTD photoresist. -1 to form a coating layer.

The size of the formed contact hole pattern was measured with a scanning electron microscope, and the results are shown in Table 3 below.

Coating layer formation temperature (占 폚) Thickness of coating layer (nm) Example 2-1 10 20 nm Example 2-2 20 20 nm Example 2-3 50 25 nm Examples 2-4 70 30 nm Example 2-5 100 20 nm Comparative Example 2-1 150 50 nm (poor CD uniformity) Comparative Example 2-2 200 Not measurable

Referring to Table 3, it can be seen that, in Examples 2-1 to 2-5, since the coating layer is formed by forming a salt between the coating resin and the NTD photoresist, the thickness of the coating layer can be controlled according to the formation temperature of the coating layer However, in the case of Comparative Examples 2-1 to 2-2, since the coating layer is formed only through the crosslinking reaction, it can be understood that the thickness can not be controlled even if the coating layer formation temperature is changed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

110: substrate
120: photoresist pattern
130: Coating layer

Claims (11)

A coating composition for fine pattern formation which is coated on a photoresist pattern to reduce the distance between patterns,
1. A coating composition for forming a fine pattern, which comprises a resin comprising a first repeating unit selected from the group consisting of repeating units represented by the following formulas (1) to (3) and combinations thereof.
[Chemical Formula 1]

(2)

(3)

The method according to claim 1,
Wherein the resin further comprises a second repeating unit selected from the group consisting of repeating units represented by the following formulas (4) and (5), and combinations thereof.
[Chemical Formula 4]

[Chemical Formula 5]

(In the formula (4), n ₁ is an integer of 0 to 5) 3. The method of claim 2,
Wherein the resin comprises the first repeating unit and the second repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01. The method according to claim 1,
Wherein the resin further comprises a third repeating unit selected from the group consisting of repeating units represented by the following general formulas (6) and (7), and combinations thereof.
[Chemical Formula 6]

(7)

(In the formulas (6) and (7), each of n ₂ is independently an integer of 0 to 5) 5. The method of claim 4,
Wherein the resin contains the first repeating unit and the third repeating unit in a molar ratio of 0.01: 0.99 to 0.99: 0.01. The method according to claim 1,
Wherein the resin is any one selected from the group consisting of compounds represented by the following general formulas (8-1) to (8-24).
[Chemical Formulas 8-1 to 8-24]

(In the formulas (8-1) to (8-24)
Wherein n ₁ to n ₂ are each independently an integer from 0 to 5, wherein l is a real number of 0.01 <l≤1, wherein m is a real number of 0≤m <0.99, and n is the 0≤n <0.99 And l, m and n satisfy 1 + m = 1 or 1 + m + n = 1, The method according to claim 1,
Wherein the coating composition for fine pattern formation further comprises a water-soluble solvent comprising 100 parts by weight of water and 1 to 20 parts by weight of an alcohol. 8. The method of claim 7,
Wherein the coating composition for fine pattern formation comprises 100 parts by weight of the water-soluble solvent and 0.01 to 15 parts by weight of the resin. 8. The method of claim 7,
Wherein the alcohol is an alkoxy alcohol. Forming a photoresist pattern, and
Coating a coating composition for forming a fine pattern according to claim 1 on the photoresist pattern. 11. The method of claim 10,
Wherein the step of coating the coating composition for fine pattern formation is performed at a temperature of less than 100 ° C.

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