Organic composition for Anti-reflection coating and Anti-reflection coating containing same

Abstract

The present invention relates to an organic composition for an anti-reflection coating, and an anti-reflection coating containing same and, more specifically, to an organic composition for an anti-reflection coating, and an anti-reflection coating comprising same, wherein in a lithography process, precise patterning can be implemented by minimizing light source reflectance of a bottom anti-reflective coating (BARC), coating properties are excellent, and pyrolysis resistance is high, thereby minimizing the generation of hazardous substances and fumes and exhibiting high transparency.

Description

Organic composition for antireflection film and antireflection film comprising the same

[0001] The present invention relates to an organic composition for an anti-reflection coating and an anti-reflection coating comprising the same, and more particularly, to an organic composition for an anti-reflection coating and an anti-reflection coating comprising the same, which can minimize the light source reflectance of a bottom anti-reflective coating (BARC) in a lithography process to realize precise patterning, have excellent coatability, and have high thermal decomposition resistance to minimize the generation of hazardous substances and fumes and exhibit high transparency.

[0002] The recent increase in semiconductor device integration, coupled with the continued development of DRAM and NAND devices, has led to a growing demand for implementing fine-patterned circuits. Accordingly, hardmask materials used in lithography processes are also being developed to meet this demand. This increased integration of semiconductor devices results in ultra-fine patterns measuring 0.10 microns or less, and lithography processes utilizing shorter wavelengths of light, far beyond the traditional g-line or i-line wavelengths, are now required. Accordingly, microlithography processes utilizing short-wavelength KrF excimer lasers and ArF excimer lasers are currently being used in semiconductor device manufacturing processes.

[0003] As semiconductor device patterns become increasingly miniaturized, the reflectivity of the bottom anti-reflection coating (BARC) on the wafer during the exposure process must be minimized to ensure uniform photoresist properties for pattern formation, resulting in uniform fine patterns and increased process efficiency. From this perspective, development of anti-reflection coating materials, among the various materials used in semiconductor processes to lower the reflectivity of the bottom anti-reflection coating, is continuously underway.

[0004] Up to now, it can be divided into an inorganic material-based lower anti-reflection film formed of materials such as titanium, chromium oxide, and carbon dioxide, and an organic material-based lower anti-reflection film made of a material that absorbs the light source, which are used to minimize the reflectance of the light source.

[0005] An anti-reflection film is a material with light absorption properties applied under a photoresist (PR) to prevent reflection of the lower anti-reflection film and to control reflectivity, thereby suppressing or eliminating standing waves that occur at the photosensitive interface due to light interference (amplification and attenuation) during exposure. By suppressing the occurrence of standing waves as much as possible, good exposure is enabled during the semiconductor device manufacturing process, thereby contributing to the implementation of circuits with increasingly fine patterns. Therefore, it is necessary to develop a material and process technology for the lower anti-reflection film that has excellent anti-reflection performance and can suppress the occurrence of standing waves.

[0006] The antireflection film must contain a substance that can absorb light in the wavelength range of the exposure light source, and must not be dissolved and destroyed by the photoresist solvent during the process of laminating the antireflection film and then laminating the photoresist. To achieve this, the antireflection film must be manufactured with a structure that can be cured by heat. In addition, the antireflection film must not be reactive with the photoresist on top. Furthermore, compounds such as amines and acids must not migrate into the photoresist layer. This is because this can cause problems such as footing and undercutting that occur during exposure. In addition, it must have optical properties suitable for various exposure processes according to various substrates, such as an appropriate refractive index and absorption coefficient, and excellent adhesion to the substrate and photoresist and coating properties are required.

[0007] Meanwhile, there is a growing need to minimize hazardous substance emissions from industrial processes and prevent the thermal decomposition of materials due to the heat generated during semiconductor manufacturing, the generation of fumes resulting from thermal decomposition, and the contamination of equipment caused by these fumes. While fumes are problematic in themselves, they also contaminate expensive and susceptible semiconductor manufacturing equipment, requiring cleaning and rinsing of the equipment to remove the contamination, increasing the additional process costs. From this perspective, antireflection coating materials used in semiconductor device manufacturing processes must also meet the following requirements: minimize hazardous substance emissions, enhance material heat resistance, and minimize fume generation.

[0008] The first object of the present invention is to provide an organic composition for an antireflection film, which is suitable for an exposure process using KrF light, and uses a novel absorber material having a high absorption at a wavelength of 248 nm with a copolymer (resin) that is highly compatible with a photoresist, thereby improving the coatability and preventing thermal decomposition of the material occurring during a thermal process, thereby maintaining the antireflection film properties of the material, while drastically improving problems of existing organic materials such as a decrease in antireflection properties due to thermal decomposition, fume generation, and color contamination, and an antireflection film comprising the same.

[0009] The second object of the present invention is to provide an organic composition for an anti-reflection film and an anti-reflection film including the same, which can enable a photoresist (PR) process to proceed smoothly, can prevent phenomena such as footing and undercut that may occur during a fine pattern process, can implement an ultra-fine pattern that can suppress or eliminate standing waves, and can shorten the process time through a single coating process.

[0010] A third object of the present invention is to provide an organic composition for an anti-reflection film and an anti-reflection film including the same, which can suppress the generation of harmful substances due to fume generation, prevent equipment contamination and failure due to fume, and increase process efficiency and cost efficiency by eliminating additional cleaning and washing processes for removing fume.

[0011] The purpose of the present invention is not limited to the aforementioned purposes, and other unmentioned purposes and advantages of the present invention can be understood through the following description and will be more clearly understood through the embodiments of the present invention. Furthermore, it will be readily apparent that the purposes and advantages of the present invention can be realized by the means and combinations thereof set forth in the claims.

[0012] In order to achieve the above purpose, according to the first aspect of the present invention, an absorbent for an antireflection film represented by the following chemical formula 1 can be provided.

[0013] [Chemical Formula 1]

[0014] In the above chemical formula 1, A1 to A4 are the same or different from each other, and each independently represents a structure represented by one of the chemical formulas a and b, and at least one of A1 to A4 is selected as a structure represented by chemical formula a, and at least one of A1 to A4 is selected as a structure represented by chemical formula b.

[0015] [chemical formula a]

[0016] [chemical formula b]

[0017] In the above chemical formulas a and b, Ar is a monocyclic or polycyclic aromatic ring group having 5 to 30 carbon atoms, which is substituted or unsubstituted with a substituent R1, n is an integer of 1 to 15, and the substituent R1 is each independently selected from deuterium, halogen, an alkyl group having 1 to 10 carbon atoms, and an aryl group having 5 to 20 carbon atoms.

[0018] At least two of the above A1 to A4 can be selected as a structure represented by the chemical formula a, and at least three can be selected as a structure represented by the chemical formula a.

[0019] Ar in the above chemical formula a is a polycyclic aromatic ring group having 10 to 20 carbon atoms.

[0020] The polycyclic aromatic ring group having 10 to 20 carbon atoms may be selected from a naphthalene group, a phenanthrene group, a triphenylene group, a fluorene group, an anthracene group, a benzanthracene group, a pyrene group, a benzopyrene group, a chrysene group, a dibenzanthracene group, and a perylene group.

[0021] The above chemical formula b may be selected from ethanoic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, pentadecanoic acid, and hexadecanoic acid.

[0022] According to a second aspect of the present invention, an antireflection film composition can be provided, comprising: an absorbent for an antireflection film according to the first aspect of the present invention; a polymer; a crosslinking agent; a thermal oxidation generator; and a solvent.

[0023] The soluble content is 0.1 to 20 wt% for 100 wt% of the above anti-reflection film composition.

[0024] The polymer may be a thermosetting resin having a crosslinking site at the terminal of a linear or branched chain.

[0025] The above crosslinking agent may include at least one selected from the following group of compounds.

[0026]

[0027] The above heat generating agent may include at least one selected from the following group of compounds.

[0028]

[0029] The solvent may include at least one selected from the group consisting of propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl lactate, propylene glycol n-propyl ether, dimethyl formamide (DMF), gamma-butyrolactone, ethoxyethanol, methoxyethanol, methyl 3-methoxypropionate (MMP), and ethyl 3-ethoxypropionate (EEP).

[0030] According to a third aspect of the present invention, an antireflection film formed from a cured product of the antireflection film composition according to the second aspect of the present invention can be provided.

[0031] According to a fourth aspect of the present invention, a method for forming a pattern of a semiconductor device can be provided, including the steps of: applying an anti-reflection film composition according to the second aspect of the present invention to an upper portion of an etching layer; curing the applied composition through a baking process and forming cross-linking to form an anti-reflection film; applying a photoresist to an upper portion of the anti-reflection film, and forming a photoresist pattern by exposure and development; and using the photoresist pattern as an etching mask to etch the anti-reflection film and then etch the etching layer to form a pattern of the etching layer.

[0032] In the step of forming the above photoresist pattern, it may include additionally performing a baking process before and after exposure.

[0033] According to a fifth aspect of the present invention, a semiconductor device manufactured by including a method for forming a pattern of a semiconductor device according to the fourth aspect of the present invention can be provided.

[0034] The organic composition for an antireflection film of the present invention and the antireflection film comprising the same are suitable for an exposure process using KrF light, and by using a novel absorber material that applies a material having high absorption at a wavelength of 248 nm with a copolymer (resin) that is highly compatible with a photoresist, the coating property can be improved, and the thermal decomposition of the material occurring during a thermal process can be prevented, thereby maintaining the antireflection film properties of the material, while dramatically improving the problems of existing organic materials such as a decrease in antireflection properties due to thermal decomposition, generation of fume, and color contamination.

[0035] In addition, the organic composition for an anti-reflection film of the present invention and the anti-reflection film comprising the same enable a subsequent photoresist (PR) process to proceed smoothly, and can prevent phenomena such as footing and undercut that may occur during a fine pattern process, while implementing an ultra-fine pattern that can suppress or eliminate standing waves, and can shorten the process time through a single coating process.

[0036] In addition, the organic composition for an anti-reflection film of the present invention and the anti-reflection film comprising the same can suppress the generation of harmful substances due to fume generation, prevent equipment contamination and failure due to fume, and eliminate the need for additional cleaning and washing processes for removing fume, thereby improving process efficiency and cost efficiency.

[0037] The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be readily apparent to those skilled in the art from the description of the claims. In addition to the effects described above, the effects of the present invention are further described below along with the description of the steps involved in implementing the invention.

[0038] Figure 1 shows a photograph for confirming fume generation in Example 1 of the present invention.

[0039] Figure 2 shows a photograph for confirming fume generation in Comparative Example 1 of the present invention.

[0040] Figure 3 shows a photograph for confirming fume generation in Comparative Example 2 of the present invention.

[0041] FIG. 4 shows the infrared (IR) spectroscopy spectra of Comparative Example 1 and Example 1 of the present invention, with the upper part of FIG. 4 being the spectrum of Comparative Example 2 and the lower part being the spectrum of Example 1.

[0042] Figure 5 shows an SEM photograph of the results of testing Example 1 according to the photoresist pattern experiment of Experimental Example 4 of the present invention.

[0043] Figure 6 shows an SEM photograph of the results of testing Comparative Example 1 according to the photoresist pattern experiment of Experimental Example 4 of the present invention.

[0044] Figure 7 shows an SEM photograph of the results of testing non-comparative example 2 according to the photoresist pattern experiment of experimental example 4 of the present invention.

[0045] The aforementioned purposes, features, and advantages are described in detail below with reference to the present specification, thereby enabling those skilled in the art to readily implement the technical concepts of the present invention. In describing the present invention, detailed descriptions of known technologies related to the present invention will be omitted if they are deemed to unnecessarily obscure the gist of the invention.

[0046] In describing this specification, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of this specification, the detailed description is omitted.

[0047] In this specification, when the terms "includes," "has," "contains," "arranges," and "provides" are used for a component, other parts may be added, unless "only" is used. When a component is expressed in the singular, it includes the plural unless otherwise explicitly stated.

[0048] When it is said in this specification that an element is “on” or “below” another element, this includes not only cases where the element is in contact with the other element, but also cases where another element exists between the elements.

[0049]

[0050] Hereinafter, the present invention will be described in more detail.

[0051] The light absorber included in the organic anti-reflection film can be classified into a case where the light absorbing chemical species, which is a light absorbing chemical species, is included in the compound and a case where the light absorber is separated from the polymer, which is not capable of light absorption. Typically, the light absorber is used separately so that the amount of the light absorbing chemical species can be controlled. According to the present invention, a light absorber represented by the following chemical formula 1 can be provided.

[0052] [Chemical Formula 1]

[0053] In the above chemical formula 1, A1 to A4 are the same or different from each other, and each independently represents a structure represented by one of the following chemical formulas a and b.

[0054] [chemical formula a]

[0055] [chemical formula b]

[0056] The above chemical formulas a and b are a carboxyl group-containing aryl group and a carboxyl group-containing chain aliphatic group, respectively. When examining the reaction with a thermosetting compound, which is a polymer to be described later, the carboxyl group reacts with a functional group such as acetal, epoxy, or hemiacetal of the thermosetting compound to form a cross-linked structure.

[0057] In the above chemical formula a, Ar may be a monocyclic or polycyclic aromatic ring group having 5 to 30 carbon atoms, substituted or unsubstituted with a substituent R1, and n may be an integer of 1 to 15.

[0058] The absorbent represented by the above chemical formula 1 can be synthesized using a tetra-p-phenol derivative represented by the following chemical formula 1-1 as the main skeleton.

[0059] [Chemical Formula 1-1]

[0060] The structural feature is that the epoxy group included in the above chemical formula 1-1 undergoes a ring-opening reaction to introduce the above chemical formulas a and b.

[0061] Chemical formula a is an aromatic ring group containing a carboxyl group, which acts as a chromophore, and chemical formula b is a chain aliphatic carboxylic acid, which improves solubility in the composition, thereby enhancing dispersibility and coatability characteristics. Therefore, chemical formula 1 must include at least one of chemical formula a and chemical formula b.

[0062] Therefore, at least one of A1 to A4 is selected as a structure represented by chemical formula a, and at least one of A1 to A4 is selected as a structure represented by chemical formula b. When the chemical formula a exists in multiple copies, the structures of the chemical formulas a selected from A1 to A4 may be the same or different from each other. In addition, when the chemical formula b exists in multiple copies within the chemical formula 1, the structures of the chemical formulas b selected from A1 to A4 may be the same or different from each other.

[0063] According to one embodiment of the present invention, at least two of A1 to A4 may be selected as a structure represented by the chemical formula a, and at least three may be selected as a structure represented by the chemical formula a.

[0064] According to one embodiment of the present invention, since Ar of the chemical formula (a) is a structure for applying a high-carbon compound to secure light absorption, Ar may be a polycyclic aromatic ring group having 10 to 20 carbon atoms, and for example, may be a polycyclic aromatic ring group having 10 to 15 carbon atoms.

[0065] According to one embodiment of the present invention, Ar may be selected from a naphthalene group, a phenanthrene group, a triphenylene group, a fluorene group, an anthracene group, a benzanthracene group, a pyrene group, a benzopyrene group, a chrysene group, a dibenzanthracene group, and a perylene group.

[0066] The above substituent R1 is present when one or more hydrogen atoms of Ar are substituted, and when there are multiple R1s, they can each be independently selected from deuterium, halogen, an alkyl group having 1 to 10 carbon atoms, and an aryl group having 5 to 20 carbon atoms. However, according to one embodiment of the present invention, chemical formula a can have a structure of an unsubstituted carboxyl group-containing aryl group.

[0067] The above chemical formula b represents a chain aliphatic carboxylic acid, and in order to ensure solubility, n, which is the number of carbon atoms excluding the carboxyl group (-COOH), may be an integer from 1 to 15, for example, n may be an integer from 5 to 10.

[0068] According to one embodiment of the present invention, chemical formula b may be selected from ethanoic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, pentadecanoic acid, and hexadecanoic acid. According to one embodiment of the present invention, n of chemical formula b may be an integer from 5 to 10.

[0069] The light absorbent represented by Chemical Formula 1 of the present invention can be obtained through a synthetic reaction of a tetra-p-phenol derivative (Chemical Formula 1-1), an aromatic ring group containing a carboxyl group capable of introducing a structure of Chemical Formula a, and an aliphatic carboxylic acid capable of introducing a structure of Chemical Formula b. The synthesis temperature of the compound can be selected and used depending on the solvent, and is 5°C°C, preferably 20°C°C.

[0070] As a synthetic solvent usable in the present invention, one or more of benzene, toluene, xylene, halogenated benzene, diethyl ether, tetrahydrofuran, esters, ethers, lactones, ketones, and amides may be selected and used.

[0071] According to one embodiment of the present invention, by synthesizing 9-anthracenecarboxylic acid (9-ACA) to introduce the main skeletal structure of chemical formula 1-1 and chemical formula a and octanoic acid to introduce chemical formula b, a synthetic structure as shown in chemical formula 2 below can be obtained.

[0072] [Chemical Formula 2]

[0073] According to the present invention, an antireflection film composition comprising the novel light absorber; a polymer; a crosslinking agent; a thermal oxidation generator; and a solvent can be provided. The light absorber is an absorber represented by Chemical Formula 1, specifically, Chemical Formula 2, as described above.

[0074] It is preferable that the soluble content be 0.1 to 20 wt% for 100 wt% of the above anti-reflection coating composition. This is because when the solid content exceeds 20 wt% and reaches approximately 25 wt% of the 100 wt% of the anti-reflection coating composition, the solubility decreases and curing does not occur.

[0075] The polymer included in the antireflection coating composition of the present invention can be obtained by polymerizing an acrylate monomer, a maleic anhydride monomer, a phenol monomer, and / or an ester monomer, and is not particularly limited as long as it is a thermosetting polymer that contains a crosslinking site capable of crosslinking at a straight chain or branched chain terminal.

[0076] Antireflection films using such polymers are cured after being applied to a substrate and then baked, thereby achieving solvent solubility. Therefore, when a photosensitive agent is applied after laminating the antireflection film, the antireflection film is not dissolved by the photosensitive agent's solvent, thereby ensuring stability.

[0077] In addition, the antireflection coating composition of the present invention may include an additive to improve curing and performance of the light absorber and polymer, and the additive may include a crosslinking agent and a thermal acid generator (TAG).

[0078] The cross-linker is preferably a compound having at least two cross-linking functional groups, and may be an imidazole-based cross-linker. According to one embodiment of the present invention, the cross-linker may include one or more compounds selected from the group of compounds shown in Table 1 below.

[0079] [Table 1]

[0080]

[0081] The thermal acid generator can generate an acid having a pKa of 2.0 or less during subsequent heat treatment of the coating layer of the photoresist composition (i.e., after application or after exposure), and for example, the thermal acid generator can generate an acid at a temperature of about 250°C, for example, in a temperature range of 150 to 100°C, and can also contribute to an increase in film density. The thermal acid generator can be, for example, toluene sulfonic acid, an amine salt or pyridine salt compound of toluene sulfonic acid, an alkyl sulfonic acid, an amine salt or pyridine salt compound of alkyl sulfonic acid, or the like. According to one embodiment of the present invention, the thermal acid generator can include at least one selected from the group of compounds shown in Table 2 below.

[0082] [Table 2]

[0083]

[0084] Organic solvents that can be used in the antireflection coating composition of the present invention may include at least one selected from propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl lactate, propylene glycol n-propyl ether, dimethyl formamide (DMF), gamma-butyrolactone, ethoxyethanol, methoxyethanol, methyl 3-methoxypropionate (MMP), ethyl 3-ethoxypropionate (EEP), and the like.

[0085] Based on 100 wt% of the total antireflection coating composition of the present invention, the light absorber represented by Chemical Formula 1 may be included in an amount of 1 to 70 wt%, for example, may be included in an amount of 10 to 55 wt%, for example, may be included in an amount of 20 to 50 wt%, for example, may be included in an amount of 30 to 50 wt%, for example, may be included in an amount of 40 to 50 wt%.

[0086] Based on 100 wt% of the total antireflection coating composition of the present invention, the polymer may be included in an amount of 0.1 to 50 wt%, for example, in an amount of 1 to 40 wt%, for example, in an amount of 5 to 30 wt%, for example, in an amount of 20 to 30 wt%.

[0087] Based on 100 wt% of the total antireflection coating composition of the present invention, the crosslinking agent may be included in an amount of 1 to 50 wt%, for example, may be included in an amount of 5 to 40 wt%, for example, may be included in an amount of 10 to 30 wt%, for example, may be included in an amount of 20 to 30 wt%.

[0088] Based on 100 wt% of the total antireflection coating composition of the present invention, the thermal oxidation agent may be included in an amount of 0.1 to 20 wt%, for example, in an amount of 0.5 to 10 wt%, for example, in an amount of 1 to 5 wt%, for example, in an amount of 2 to 4 wt%.

[0089] When an antireflection film composition satisfying the composition and content as described above is applied onto a wafer and then a thermal process such as baking is performed, acid is generated from the thermal acid generator, and in the presence of the generated acid, a crosslinking reaction between the light absorber represented by Chemical Formula 1, the polymer, and the crosslinking agent used as an additive is promoted, thereby forming an antireflection film that is insoluble in an organic solvent. The antireflection film formed in this way can absorb ultraviolet rays that have penetrated the photoresist and reached therefrom, thereby preventing diffuse reflection from the photoresist lower layer.

[0090] According to a third aspect of the present invention, a method for forming a pattern of a semiconductor device using a semiconductor using the anti-reflection film may include the steps of: applying an anti-reflection film composition on an upper portion of a layer to be etched; curing the applied composition through a baking process and forming cross-linking to form an anti-reflection film; applying a photoresist on the upper portion of the anti-reflection film, and forming a photoresist pattern by exposure and development; and using the photoresist pattern as an etching mask to etch the anti-reflection film and then etch the layer to be etched to form a pattern of the layer to be etched.

[0091] The process of forming an anti-reflection film by applying and curing the anti-reflection film of the present invention is performed by a baking process, and at this time, the baking process can be performed at a temperature range of 150 to 250°C, and can be performed for, for example, 0.5 to 5 minutes.

[0092] In addition, in the pattern forming method according to the present invention, the step of forming the photoresist pattern may further include performing a baking process before and after exposure, and this baking process may be performed at a temperature of 70 to 200°C.

[0093] As described above, the antireflection coating composition according to the present invention can exhibit excellent coatability and transparency, and maintains the antireflection coating properties of the material by preventing thermal decomposition of the material that occurs during a thermal process, thereby exhibiting excellent resolution in ultra-fine patterns. In addition, it can dramatically improve problems of existing organic materials such as deterioration of antireflection properties due to thermal decomposition, generation of fumes, and color contamination, and process efficiency can be increased because pollutants such as fumes are not generated.

[0094] In addition, by forming a pattern using an organic anti-reflection film composition, the anti-reflection film can be rapidly etched in an ultra-fine pattern formation process using a 248 nm light source, and can contribute to the manufacturing of highly integrated semiconductors.

[0095] Hereinafter, the present invention will be described in more detail by way of examples. However, the following examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following examples.

[0096] [Example 1]

[0097] Synthesis Example 1

[0098] Tetraglycidyl ether 1,1,2,2-tetraphenyl ethane (12 g, 1 eq), 9-anthracene carboxylic acid (12.42 g, 2.9 eq), n-octanoic acid (2.78 g, 1 eq), benzyltriethyl ammonium chloride (0.4 g), and propylene glycol monomethyl ether (82.78 g, PGME) were added to a flask, and the inside of the flask was heated to 1130°C and stirred for 24 hours to allow a reaction. The reactant was neutralized with pyridine, purified with a 1 wt% aqueous hydrochloric acid solution and distilled water, and then distilled to obtain light absorbent compound A of chemical formula 2.

[0099] Synthesis Example 2

[0100] 29.4 g of maleic anhydride, 30 g of methyl methacrylate, and 2.97 g of AIBN were dissolved in 120 g of 1,4-dioxane, and polymerization was performed at 70°C for 12 hours. After the reaction was completed, the reaction solution was dropped into methyl alcohol, and the resulting precipitate was filtered, washed several times with methyl alcohol, and vacuum-dried (Mw = 47,100, PDI = 2.17, yield = 58%). 72 g of the vacuum-dried polymer and 0.55 g of toluene sulfonic acid monohydrate were mixed into 725 g of methyl alcohol, and reacted at 70°C for 48 hours. After the reaction was completed, the reaction solution was dropped into distilled water, the resulting precipitate was filtered, washed several times with distilled water, and vacuum-dried to obtain “Polymer 1 (yield 58%)”.

[0101] Manufacturing Example 1

[0102] An antireflection coating composition of Example 1 was prepared by dissolving 2.45 g of the light absorber prepared in Synthesis Example 1, 1.05 g of the polymer prepared in Synthesis Example 2, 1.375 g of 1,3,4,6-tetrakis(butoxymethyl)glycoluril as a curing agent, and 0.125 g of pyridinium p-toluenesulfonic acid as a thermal acid generator in 95 g of propylene glycol monomethyl ether acetate, and then filtering the mixture through a membrane filter having a diameter of 0.1 μm. The ratios (by weight) of the combined light absorber, polymer, curing agent, and thermal acid generator are shown in Table 3 below.

[0103]

[0104] [Comparative Example 1]

[0105] Synthesis Example 3

[0106] 109 g of benzophenone tetracarboxylic dianhydride, 140 g of anthracene methanol, and 7.3 g of isopropylethylamine were dissolved in 540 g of 1,4-dioxane, and reacted at 50°C for 16 hours. After the reaction was complete, formic acid was dropped into the reaction solution to neutralize it. The reactant was dropped into water, and the resulting precipitate was filtered, washed several times with distilled water, and dried to obtain a light absorbent compound B of the following chemical formula 3.

[0107] [Chemical Formula 3]

[0108] Comparative Manufacturing Example 2

[0109] The same polymer, crosslinking agent, and thermal oxidation generator as in Manufacturing Example 1 were used, but the light absorbing compound was not the compound according to Synthesis Example 1, but Compound B according to Synthesis Example 3, and the antireflection coating composition of Comparative Example 1 was prepared in a ratio as described in Table 3 below.

[0110]

[0111] [Comparative Example 2]

[0112] Synthesis Example 4

[0113] 75 g of 4,4'-oxydiphthalic anhydride, 100 g of anthracene methanol, and 7.3 g of diisopropylethylamine were dissolved in 540 g of 1,4-dioxane, and reacted at 50°C for 16 hours. After the reaction was complete, formic acid was dropped into the reaction solution to neutralize it. The reactant was dropped into water, and the resulting precipitate was filtered, washed several times with distilled water, and dried to obtain a light absorbent compound C of the following chemical formula 4.

[0114] [Chemical Formula 4]

[0115] Comparative Manufacturing Example 2

[0116] An antireflection coating composition of Comparative Example 1 was prepared using the same polymer, crosslinking agent, and thermal oxidation generator as in the above-described Manufacturing Example 1, but using Compound C according to Synthesis Example 4 instead of the compound according to Synthesis Example 1 as the light absorbing compound, in a ratio as described in Table 3 below.

[0117] [Table 3]

[0118]

[0119]

[0120] [Experimental Example]

[0121] Experimental Example 1 - Measurement of thickness and refractive index (n) and extinction coefficient (k)

[0122] After bringing a sample of the composition for an anti-reflection film into a clean room, it was coated on an 8-inch silicon wafer using track equipment (Tokyo Electron, TEL-MARK 8), and then the composition for an anti-reflection film was cured through a baking process on a hot plate for 1 minute at a curing temperature of 230°C, and then an anti-reflection film test sample was manufactured, and then taken out of the clean room.

[0123] The thickness of the antireflection film of the above experimental sample was measured using a DNS VM-120 device, and the refractive index (n) and extinction coefficient (k) were measured at 248 nm using a spectroscopic ellipsometer (Eliipsometer JA woolams / V-Vase). The results are shown in Table 4 below.

[0124] [Table 4]

[0125]

[0126] As can be seen in Table 4 above, Example 1, Comparative Examples 1 and 2 were manufactured to have almost identical values ​​for thickness, refractive index (n) and extinction coefficient (k) in order to identify the source of contamination for the same fume.

[0127]

[0128] Experimental Example 2 - Stripping Experiment

[0129] In the above Experimental Example 1, after measuring the thickness, refractive index (n), and extinction coefficient (k), it was confirmed that 100% curing was achieved by varying the curing temperature. In addition, after the wafer with the anti-reflection film laminated on it went through a rework process using Thinner (OK7030), the thickness, refractive index (n), and extinction coefficient (k) were measured again, and the differences were expressed as △T (thickness difference), △n (refractive index difference), and △k (extinction coefficient difference), and the results are summarized in Table 5 below.

[0130] [Table 5]

[0131]

[0132] Referring to Table 5 above, the antireflection coating composition of the present invention achieved a curing rate of 100% even when the curing temperature was varied from 180°C to 260°C, confirming that it can be utilized under various process temperature conditions. In addition, it was confirmed that the physical properties were excellent, as there was no change in the thickness, refractive index, and extinction coefficient even after the rework process for the stripping test.

[0133]

[0134] Experimental Example 3 - Evaluation of Hazardous Substances, Fume Generation, and Color

[0135] 1 g of the antireflection coating composition was taken as a sample and placed in an aluminum dish, baked at 120°C for 90 seconds to remove the solvent from the sample, and then air particles were measured 5 times by particle size using an air particle counter at 230°C, and the results are shown in Table 6 below.

[0136] After measurement, the captured material was visually observed to confirm its color. Photographs of the captured material of Example 1 and Comparative Examples 1 and 2 are shown in FIGS. 1 to 3, respectively.

[0137] [Table 6]

[0138]

[0139] As can be seen in Table 6 above, compared to Comparative Examples 1 and 2, Example 1 had a significantly reduced amount of measured air particles, and while Fig. 1 of Example 1 showed that the captured material was transparent and no fume was generated, the captured material of Comparative Examples 1 and 2 showed a yellow color, indicating that fume was generated, and there is a problem that transparency is greatly reduced when coated.

[0140] Additionally, infrared (IR) spectroscopy spectra were confirmed for each of Comparative Example 2 and Example 1, and are shown in FIGS. 4 and 5, respectively. The part indicated by the dotted line in FIG. 4 indicates a yellow substance detected in the sample of Comparative Example 2, and unlike FIG. 4, no yellow substance detection peak was confirmed in FIG. 5.

[0141] The inventors of the present invention have confirmed that when a high-carbon compound is introduced through a ring-opening reaction using phthalic anhydride as in the prior art of Comparative Examples 1 and 2, harmful substances that cause fume or yellowing of an antireflection film are emitted, and in the present invention, a light absorbent that does not use a ring-opening reaction of phthalic anhydride has been derived.

[0142]

[0143] Experimental Example 4 - Photoresist Pattern Experiment

[0144] After bringing a sample of the composition for an anti-reflection film into a clean room, it was coated on an 8-inch silicon wafer using track equipment (Tokyo Electron, TEL-MARK 8), and then baked on a 230°C hot plate for 1 minute to harden the composition for an anti-reflection film, thereby manufacturing an anti-reflection film test sample, and then taken out of the clean room.

[0145] After that, krF photoresist was applied on top of the manufactured anti-reflection film and baked at 100℃ for 60 seconds (soft bake). After that, exposure was performed using scanner equipment (Nikon S-203B, NA=0.68 Conv. (Sigma:0.75)) and baking (post treatment bake) was performed at 100℃ for 60 seconds. The exposed wafer was developed with a developer containing 2.38 wt% of tetramethylammonium hydroxide (TMAH) to obtain the final photoresist pattern. It was confirmed that the pattern size could implement 180 nm line (1:1 pitch) performance. The CD-SEM and V-SEM images of Experimental Example 4 are shown in Fig. 6, and the EOP, EL, and DOF values ​​were measured and shown in Table 7 below.

[0146] [Table 7]

[0147]

[0148] In Table 7 above, Eop refers to the energy required to implement the target pattern, and was measured using exposure equipment (Nikon NSR-204B), EL refers to the rate of change in pattern size per 1 mj, and was measured using the CD-SEM method, and DoF refers to the height (Focus) above and below the lens, and was measured using (Nikon NSR-204B).

[0149]

[0150] Although the present invention has been described in more detail with reference to the embodiments of this specification, this specification is not necessarily limited to these embodiments, and various modifications may be implemented without departing from the technical spirit of this specification. Therefore, the embodiments disclosed in this specification are not intended to limit the technical spirit of this specification, but to explain it, and the scope of the technical spirit of this specification is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of protection of this specification should be interpreted by the claims, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of rights of this specification.

Claims

1. Light absorbing agent for antireflection film represented by the following chemical formula 1: [Chemical Formula 1] In the chemical formula 1 above, A1 to A4 are the same or different from each other, and each independently represents a structure represented by one of the chemical formulas a and b below, at least one of A1 to A4 is selected as a structure represented by chemical formula a, and at least one of A1 to A4 is selected as a structure represented by chemical formula b. [chemical formula a] [chemical formula b] In the above chemical formulas a and b, Ar is a monocyclic or polycyclic aromatic ring group having 5 to 30 carbon atoms, which is unsubstituted or substituted with a substituent R1, n is an integer of 1 to 15, and the substituent R1 is each independently selected from deuterium, halogen, an alkyl group having 1 to 10 carbon atoms, and an aryl group having 5 to 20 carbon atoms.

2. In paragraph 1, An absorbent for an antireflection film, wherein at least two of the above A1 to A4 are selected to have a structure represented by the above chemical formula a.

3. In paragraph 1, An absorbent for an antireflection film, wherein at least three of the above A1 to A4 are selected to have a structure represented by the above chemical formula a.

4. In paragraph 1, An absorbent for an antireflection film, wherein Ar in the chemical formula (a) above is a polycyclic aromatic ring group having 10 to 20 carbon atoms.

5. In paragraph 4, An absorbent for an antireflection film, wherein the polycyclic aromatic ring group having 10 to 20 carbon atoms is selected from a naphthalene group, a phenanthrene group, a triphenylene group, a fluorene group, an anthracene group, a benzanthracene group, a pyrene group, a benzopyrene group, a chrysene group, a dibenzanthracene group, and a perylene group.

6. In paragraph 1, An absorbent for an antireflection film, wherein the chemical formula b is selected from ethanoic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, pentadecanoic acid, and hexadecanoic acid.

7. Containing an absorbent for an anti-reflection film; a polymer; a crosslinking agent; a thermal acid generator; and a solvent; A composition for an anti-reflection film, wherein the light absorbing agent for the anti-reflection film is according to any one of claims 1 to 6.

8. In paragraph 7, An anti-reflection film composition having a soluble content of 0.1 to 20 wt% relative to 100 wt% of the anti-reflection film composition.

9. In paragraph 7, A composition for an antireflection film, wherein the polymer is a thermosetting resin having a crosslinking site at the terminal of a linear or branched chain.

10. In paragraph 7, The above cross-linking agent is a composition for an anti-reflection film, comprising at least one compound selected from the following group of compounds:

11. In paragraph 7, The above-mentioned heat generating agent is a composition for an anti-reflection film, which comprises at least one compound selected from the following group of compounds:

12. In paragraph 7, A composition for an antireflection film, wherein the solvent comprises at least one selected from the group consisting of propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), cyclohexanone, ethyl lactate, propylene glycol n-propyl ether, dimethyl formamide (DMF), gamma-butyrolactone, ethoxyethanol, methoxy ethanol, methyl 3-methoxypropionate (MMP), and ethyl 3-ethoxypropionate (EEP).

13. An anti-reflection film formed from a cured product of an anti-reflection film composition according to any one of claims 7 to 12.

14. A step of applying an anti-reflection film composition according to any one of claims 7 to 12 onto an upper portion of an etching layer; A step of forming an anti-reflection film by hardening the applied composition through a baking process and forming cross-linking bonds; A step of applying photoresist on the upper part of the anti-reflection film, exposing it, and developing it to form a photoresist pattern; and A method for forming a pattern of a semiconductor device, comprising: a step of etching the anti-reflection film using the photoresist pattern as an etching mask, and then etching the etching layer to form a pattern of the etching layer.

15. In paragraph 14, A method for forming a pattern of a semiconductor device, comprising, in the step of forming the above photoresist pattern, additionally performing a baking process before and after exposure.

16. A semiconductor device manufactured by including a method for forming a pattern of a semiconductor device according to any one of claims 14 and 15.

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