HARDMASK COMPOSITION, HARDMASK LAYER AND PATTERN FORMING METHOD - Patent application

Abstract

To provide: a hardmask composition capable of forming a hardmask layer that can secure excellent etch resistance, gap-fill characteristics and heat resistance; a hardmask layer comprising a cured product of the hardmask composition; and a method of forming patterns using the hardmask composition.SOLUTION: The hardmask composition comprises a compound represented by the chemical formula 1 in the figure, and a solvent. (The definition of the chemical formula 1 is as described in the specification.)SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a hard mask composition, a hard mask layer including a cured product of the hard mask composition, and a pattern forming method using the hard mask composition. [Background technology]

[0002] In recent years, the semiconductor industry has been evolving from patterns of hundreds of nanometers to ultra-fine technology having patterns of several to tens of nanometers in size, and effective lithographic techniques are essential to realize such ultra-fine technology.

[0003] A typical lithographic technique includes forming a material layer on a semiconductor substrate, coating a photoresist layer thereon, exposing and developing the photoresist pattern to form a photoresist pattern, and then etching the material layer using the photoresist pattern as a mask.

[0004] Recently, as the size of a pattern to be formed decreases, it is difficult to form a fine pattern having a good profile using only the above-mentioned typical lithographic techniques. Therefore, a supplementary layer called a hard mask layer can be formed between a material layer to be etched and a photoresist layer to form a fine pattern. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent Publication No. 10-2021-0113909 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present invention is to provide a hard mask composition capable of forming a hard mask layer that can ensure excellent etching resistance, gap-filling properties, and heat resistance.

[0007] Another object of the present invention is to provide a hard mask layer comprising a cured product of the above hard mask composition.

[0008] A further object of the present invention is to provide a pattern forming method using the above hard mask composition. [Means for solving the problem]

[0009] The hard mask composition according to the present invention includes a compound represented by the following Chemical Formula 1, and a solvent:

[0010] [ka]

[0011] In the above chemical formula 1, Ar 1 and Ar 2 are each independently an aromatic hydrocarbon ring having 6 to 30 carbon atoms, X 1 and X 2 each independently represents a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 carbon atoms, R 1 and R 2 each independently represents a deuterium atom, a hydroxyl group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a combination thereof; n1 and n2 each independently represent an integer of 0 to 4, and n1+n2 represents an integer of 1 or more; m1 is Ar 1 is an integer greater than or equal to 0, with the maximum number of possible replacements being m2 is Ar 2is an integer greater than or equal to 0, up to the number that can be substituted for it.

[0012] Ar in the above formula 1 1 and Ar 2 is preferably any one selected from the structures listed in Group 1 below:

[0013] [ka]

[0014] Ar in the above formula 1 1 and Ar 2 is preferably any one selected from the structures listed in Group 1-1 below:

[0015] [ka]

[0016] X in the above formula 1 1 and X 2 is preferably any one of the moieties selected from the substituted or unsubstituted structures listed in Group 2 below:

[0017] [ka]

[0018] X in the above formula 1 1 and X 2 is preferably any one of moieties selected from the substituted or unsubstituted structures listed in Group 2-1 below:

[0019] [ka]

[0020] Ar in the above formula 11 and Ar 2 are each independently one of moieties selected from the structures represented by Group 1-2 below, 1 and X 2 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group, and n1 and n2 are each independently preferably 1 or 2:

[0021] [ka]

[0022] The compound represented by the above Chemical Formula 1 is preferably a compound having an asymmetric structure.

[0023] The compound represented by the above Chemical Formula 1 is preferably represented by at least one of the following Chemical Formulas 1-1 to 1-6:

[0024] [ka]

[0025] In the above Chemical Formula 1-1 to the above Chemical Formula 1-6, X 1 and X 2 are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group; n1 and n2 are an integer of 0 to 4, and n1+n2 is an integer of 1 to 4; R 1 and R 2each independently represents a deuterium atom, a hydroxyl group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a combination thereof; m1 is Ar 1 is an integer greater than or equal to 0, with the maximum number of possible replacements being m2 is Ar 2 is an integer greater than or equal to 0, up to the number that can be substituted for it.

[0026] In the above chemical formulas 1-1 to 1-6, n1 and n2 are preferably each independently 1 or 2.

[0027] The molecular weight of the above compound is preferably 500 g / mol to 10,000 g / mol.

[0028] The compound is preferably contained in an amount of 0.1% by mass to 30% by mass based on the total mass of the hard mask composition.

[0029] The solvent preferably contains at least one selected from the group consisting of propylene glycol, propylene glycol diacetate, methoxypropanediol, diethylene glycol, diethylene glycol butyl ether, tri(ethylene glycol) monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, methylpyrrolidone, methylpyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

[0030] According to another aspect of the present invention, there is provided a hardmask layer comprising the cured hardmask composition described above.

[0031] According to yet another aspect of the present invention, there is provided a method of forming a pattern, comprising the steps of providing a material layer on a substrate, applying the above-described hard mask composition on the material layer, heat-treating the hard mask composition to form a hard mask layer, forming a photoresist layer on the hard mask layer, exposing and developing the photoresist layer to form a photoresist pattern, selectively removing the hard mask layer using the photoresist pattern to expose portions of the material layer, and etching the exposed portions of the material layer.

[0032] The step of forming the hard mask layer preferably includes a step of performing a heat treatment at 100°C to 1,000°C. Effect of the Invention

[0033] According to the present invention, there is provided a hard mask composition capable of forming a hard mask layer that can ensure excellent etching resistance, gap-fill properties, and heat resistance. [Brief description of the drawings]

[0034] [Figure 1] FIG. 1 is a reference schematic diagram exemplarily showing a step of a hard mask layer to explain a method for evaluating planarization characteristics. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to exemplary embodiments thereof, so that those skilled in the art will be able to easily practice the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

[0036] Unless otherwise defined in this specification, "substituted" means that a hydrogen atom in a compound is replaced with a deuterium atom, a halogen atom (F, Br, Cl, or I), a hydroxyl group, a nitro group, a cyano group, an amino group, an azide group, an amidino group, a hydrazino group, a hydrazono group, a carbonyl group, a carbamoyl group, a thiol group, an ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a vinyl group, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkyl ...

[0046] This means that the aryl group is substituted with a substituent selected from the group consisting of an aryl group, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, an arylaryl group having 9 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, a heteroalkyl group having 1 to 20 carbon atoms, a heteroarylalkyl group having 3 to 20 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkynyl group having 6 to 15 carbon atoms, a heterocycloalkyl group having 3 to 30 carbon atoms, and combinations thereof.

[0037] Furthermore, two adjacent substituents of the above-mentioned substituted halogen atom (F, Br, Cl, or I), hydroxy group, nitro group, cyano group, amino group, azide group, amidino group, hydrazino group, hydrazono group, carbonyl group, carbamoyl group, thiol group, ester group, carboxyl group or a salt thereof, sulfonic acid group or a salt thereof, phosphoric acid or a salt thereof, alkyl group having 1 to 30 carbon atoms, alkenyl group having 2 to 30 carbon atoms, alkynyl group having 2 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, arylalkyl group having 7 to 30 carbon atoms, alkoxy group having 1 to 30 carbon atoms, heteroalkyl group having 1 to 20 carbon atoms, heteroarylalkyl group having 3 to 20 carbon atoms, cycloalkyl group having 3 to 30 carbon atoms, cycloalkenyl group having 3 to 15 carbon atoms, cycloalkynyl group having 6 to 15 carbon atoms, or heterocyclic group having 2 to 30 carbon atoms may be bonded to form a ring.

[0038] Unless otherwise defined in this specification, the terms "aromatic hydrocarbon" and "aryl group" refer to a group having one or more aromatic hydrocarbon moieties, and include not only non-fused aromatic hydrocarbon rings, fused aromatic hydrocarbon rings, but also forms in which aromatic hydrocarbon moieties are linked by single bonds, non-aromatic fused ring forms in which aromatic hydrocarbon moieties are directly or indirectly fused, or combinations thereof.

[0039] More specifically, the substituted or unsubstituted aromatic hydrocarbon ring may be, but is not limited to, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted naphthacenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, a substituted or unsubstituted quaterphenyl group, a substituted or unsubstituted chrysenyl group, a substituted or unsubstituted triphenylenyl group, a substituted or unsubstituted perylenyl group, a substituted or unsubstituted indenyl group, a combination thereof, or a condensed form of a combination thereof.

[0040] As used herein, polymers include both oligomers and polymers.

[0041] Unless otherwise specified in this specification, the "molecular weight" and "weight average molecular weight" are measured by dissolving a powder sample in tetrahydrofuran (THF) and then using Agilent Technologies' 1200 series gel permeation chromatography (GPC) (using a Shodex LF-804 column and Shodex polystyrene as the standard sample).

[0042] In the semiconductor industry, there is a continuous demand for reducing the size of chips. To meet this demand, the line width of the photoresist patterned in the lithography technology must be several tens of nanometers in size. Therefore, the height that can be withstood by the line width of the photoresist pattern is limited, and the photoresist may not be able to withstand the etching step. To compensate for this, an auxiliary layer called a hard mask layer is used between the material layer to be etched and the photoresist layer. This hard mask layer serves as an intermediate film that transfers the fine pattern of the photoresist to the material layer through selective etching. Therefore, the hard mask layer is required to have etching resistance so that it can withstand the etching process required for pattern transfer. Therefore, research is being conducted to maximize the carbon content of the hard mask composition in order to improve the etching resistance of the hard mask layer.

[0043] Existing hard mask layers have been formed by chemical or physical deposition methods, but this requires large equipment scale and high process costs, resulting in poor economic efficiency. Therefore, a technology for forming a hard mask layer by a spin coating method has been developed recently. The spin coating method is easier to process than conventional methods, and the hard mask layer manufactured using this method may have better gap filling and planarization properties. However, the hard mask layer formed using the spin coating method has a problem that the required etching resistance is somewhat reduced. Therefore, it is required that a hard mask composition that can be applied to the spin coating method and the hard mask layer formed using this method have the same etching resistance as a hard mask layer formed using a chemical or physical deposition method.

[0044] Therefore, research has been conducted to maximize the carbon content of hard mask compositions in order to improve the etching resistance of the hard mask layer. However, as the carbon content of the polymer contained in the hard mask composition increases, the solubility in a solvent tends to decrease. Therefore, the carbon content of the polymer contained in the hard mask composition must be maximized to improve the etching resistance of the hard mask layer formed therefrom, while the polymer must be well soluble in a solvent.

[0045] The hard mask composition according to the present invention contains a macromolecule containing an aromatic hydrocarbon ring, thereby increasing the carbon content in the composition. Therefore, the hard mask layer formed from the composition can ensure excellent heat resistance and excellent etching resistance. In addition, the compound contains a specific functional group, thereby increasing the carbon content in the composition while suppressing a decrease in solubility in a solvent.

[0046] Specifically, the hard mask composition according to the present invention includes a compound represented by the following Chemical Formula 1 and a solvent:

[0047] [ka]

[0048] In the above chemical formula 1, Ar 1 and Ar 2 are each independently an aromatic hydrocarbon ring having 6 to 30 carbon atoms, X 1 and X 2 each independently represents a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 carbon atoms, R 1 and R 2 each independently represents a deuterium atom, a hydroxyl group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a combination thereof; n1 and n2 each independently represent an integer of 0 to 4, and n1+n2 represents an integer of 1 or more; m1 is Ar 1 is an integer greater than or equal to 0, with the maximum number of possible replacements being m2 is Ar 2 is an integer greater than or equal to 0, up to the number that can be substituted for it.

[0049] Here, we will explain the above "substitutable number". For example, Ar 1 For example, when the compound represented by formula 1 is a benzene ring, the number of carbon atoms in the benzene ring is six, but one carbon atom is bonded to an oxygen atom, and Ar 1 is -(CH(OH)X 1 Since the benzene ring has n1 ) groups, the "number of substitutions" is [6-1-(n1)]. Therefore, Ar 1 When m is a benzene ring, the range of m1 is 0 or more and [6-1-(n1)] or less.

[0050] Ar 1 In the case of a phenanthrene ring, the number of carbon atoms in the phenanthrene ring is 14, but the number of carbon atoms that can be substituted is 10. Of the 10 carbon atoms, one carbon atom is bonded to an oxygen atom, and Ar 1 is -(CH(OH)X 1 ) groups, so Ar 1 When m is a phenanthrene ring, the range of m1 is 0 or more and [10-1-(n1)] or less.

[0051] The compound represented by Chemical Formula 1 is a macromonomolecular material containing two or more aromatic hydrocarbon rings and formed by linking aromatic hydrocarbons with a linking group. Therefore, a hard mask layer formed from a composition according to the present invention containing the compound represented by Chemical Formula 1, which has a high carbon content, can simultaneously improve etching resistance and heat resistance. In addition, since the compound represented by Chemical Formula 1 is in a monomolecular form, the gap fill property and void property of a hard mask layer formed from a composition containing the compound can be improved.

[0052] The compound represented by Chemical Formula 1 contains an ether group (ether structure) as a linking group, and thus can suppress a decrease in solubility in a solvent, despite the high carbon content in the compound. In addition, without being limited to the above, the compound represented by Chemical Formula 1 can increase its solubility in a solvent by containing at least one tertiary carbon atom substituted with a hydroxy group. In addition, the compound represented by Chemical Formula 1 can provide a crosslinking site for a polymerization reaction by containing a hydroxy group, and therefore, when a composition containing the compound is heated, Ar is bonded to the crosslinking site provided by the hydroxy group. 1 or Ar 2 The aromatic hydrocarbon rings represented by the formula (I) can be directly linked to each other. This allows the monomers represented by the formula (I) to be polymerized more densely, so that the planarization properties, gap-fill properties, and void properties of the hard mask layer formed therefrom can be further improved.

[0053] Ar in the above formula 1 1 and Ar 2 may each independently be any one selected from the structures listed in Group 1 below, for example, any one selected from the structures listed in Group 1-1 below, for example, any one selected from the structures listed in Group 1-2 below, but are not limited thereto:

[0054] [ka]

[0055] Ar in the above formula 1 1 and Ar 2 are each independently R 1 or R 2 or Ar 1 and Ar 2 Either one of R in the above formula 1 may be an unsubstituted group. 1 and R 2may each independently be a deuterium atom, a hydroxy group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 24 carbon atoms, or a combination thereof, for example, a deuterium atom, a hydroxy group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 5 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a combination thereof, for example, a hydroxy group, a halogen atom, a methoxy group, an ethoxy group, a propoxy group, a methyl group, an ethyl group, a propyl group, or a butyl group, but is not limited to these.

[0056] X in the above formula 1 1 and X 2 may each independently be any one of the moieties selected from the substituted or unsubstituted structures listed in Group 2 below, for example, any one of the moieties selected from the substituted or unsubstituted structures listed in Group 2-1 below, for example, but not limited to, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group:

[0057] [ka]

[0058] In the above formula 1, n1 and n2 are each independently an integer of 0 to 4, for example, an integer of 0 to 3, for example, an integer of 1 to 3, for example, 1 or 2, but are not limited thereto. In addition, n1+n2 is an integer of 1 or more, for example, an integer of 1 to 6, for example, an integer of 1 to 4, for example, 2 or 3, but are not limited thereto.

[0059] In the above chemical formula 1, Ar 1 and Ar 2 may be the same or different. 1 and X 2 may be the same or different from each other. 1 and Ar 2 When X have the same structure, the positions of the carbon atoms connected to the oxygen atoms (-O-) may be the same or different. 1 and X 2 If and are identical to each other, then X 1 or X 2 The positions of the carbon atoms connected to the adjacent carbon atoms of may be the same or different from each other. Therefore, the compound represented by the above Chemical Formula 1 may have a symmetric structure or an asymmetric structure as a whole. When the above Chemical Formula 1 has an asymmetric structure, the solubility of the compound represented by the above Chemical Formula 1 in a solvent may be further increased. A molecule having a symmetric structure means, for example, a molecule having C2 symmetry, and in Chemical Formula 1, the oxygen atom depicted in the center is the symmetric center, and the substituents -Ar on the left and right are the symmetric center and the substituents -Ar on the right and left are the symmetric center ... 1 ((R 1 ) m1 )-(CH(OH)X 1 ) n1 And-Ar 2 ((R 2 ) m2 )-(CH(OH)X 2 ) n2 In addition, a molecule having an asymmetric structure means that the molecule does not have, for example, C2 symmetry, and in chemical formula 1, the oxygen atom depicted in the center is the center of symmetry, and the substituents -Ar 1 ((R 1 ) m1 )-(CH(OH)X 1 ) n1 And-Ar 2 ((R 2 ) m2 )-(CH(OH)X 2 ) n2 and may be different from each other.

[0060] In one embodiment, the compound represented by Chemical Formula 1 may be at least one of the compounds represented by Chemical Formulas 1-1 to 1-6 below:

[0061] [ka]

[0062] In the above chemical formulas 1-1 to 1-6, X 1 , X 2 , R 1 , and R 2 may be as defined in Chemical Formula 1 above, for example, but not limited to, each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group.

[0063] In the above Chemical Formula 1-1 to Chemical Formula 1-6, n1 and n2 may be one of integers from 0 to 4, and n1+n2 may be one of integers from 1 to 4. n1 and n2 may be, for example, one of integers from 0 to 4, for example, one of integers from 0 to 3, for example, one of integers from 1 to 3, for example, 1 or 2, but are not limited thereto. In addition, n1+n2 may be, for example, one of integers from 1 to 4, for example, 2 or 3, but are not limited thereto.

[0064] In the above chemical formulas 1-1 to 1-6, m1 is Ar 1 m2 is an integer of 0 or more, with the upper limit being the number of substitutions that can be made with Ar 2 m1 and m2 are, for example, an integer of 0 or more, up to the number of substitutions that can be made with m1 and m2. m1 and m2 are, for example, an integer of 0 to 6, for example, an integer of 0 to 4, for example, an integer of 0 to 2, for example, 0 or 1, but are not limited thereto.

[0065] The compound may have a molecular weight of 500 g / mol to 10,000 g / mol. For example, the compound may have a molecular weight of 500 g / mol to 9,500 g / mol, for example, 500 g / mol to 9,000 g / mol, for example, 600 g / mol to 8,500 g / mol, for example, 600 g / mol to 8,000 g / mol, for example, 700 g / mol to 7,500 g / mol, for example, 700 g / mol to 7,000 g / mol, but is not limited thereto. By having a molecular weight in the above range, the carbon content and solubility in a solvent of the hard mask composition containing the compound may be adjusted and optimized.

[0066] The compound may be contained in an amount of 0.1% by mass to 30% by mass based on the total mass of the hard mask composition. For example, it may be 0.2% by mass to 30% by mass, for example, 0.5% by mass to 30% by mass, for example, 1% by mass to 30% by mass, for example, 1% by mass to 25% by mass, for example, 1% by mass to 20% by mass, but is not limited thereto. By containing the compound in the above range, the thickness, surface roughness, and flattening degree of the hard mask can be easily adjusted.

[0067] The above compounds can be synthesized by appropriately referring to conventionally known synthesis methods. More specifically, those skilled in the art can easily synthesize the compounds by referring to the synthesis methods described in the Examples.

[0068] The hard mask composition according to the present invention includes a solvent. In one embodiment, the solvent may include, but is not limited to, at least one selected from the group consisting of propylene glycol, propylene glycol diacetate, methoxypropanediol, diethylene glycol, diethylene glycol butyl ether, tri(ethylene glycol) monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, methylpyrrolidone, methylpyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate. The solvent is not particularly limited as long as it has sufficient solubility and / or dispersibility in the polymer.

[0069] The hard mask composition may further include additives such as a surfactant, a crosslinking agent, a thermal acid generator, and a plasticizer.

[0070] Examples of the surfactant that can be used include, but are not limited to, fluoroalkyl compounds, alkylbenzenesulfonates, alkylpyridinium salts, polyethylene glycols, and quaternary ammonium salts.

[0071] Examples of the crosslinking agent include melamine-based agents, substituted urea-based agents, and polymer forms thereof. Preferably, a crosslinking agent having at least two crosslink-forming substituents can be used, such as methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or butoxymethylated thiourea.

[0072] In addition, as the crosslinking agent, a crosslinking agent having high heat resistance can be used. As the crosslinking agent having high heat resistance, a compound containing a crosslinking-forming substituent having an aromatic ring (e.g., a benzene ring, a naphthalene ring) in the molecule can be used.

[0073] Examples of the thermal acid generator that can be used include, but are not limited to, acidic compounds such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonate, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, hydroxybenzoic acid, and naphthalenecarboxylic acid, and / or 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, and organic sulfonic acid alkyl esters.

[0074] According to another embodiment, a hardmask layer can be provided that includes a cured version of the hardmask composition described above.

[0075] A method for forming a pattern using the above-described hard mask composition will now be described.

[0076] A patterning method according to one embodiment includes providing a material layer over a substrate, applying a hardmask composition over the material layer, the hardmask composition including the compound and a solvent, thermally treating the hardmask composition to form a hardmask layer, forming a photoresist layer over the hardmask layer, exposing and developing the photoresist layer to form a photoresist pattern, selectively removing the hardmask layer using the photoresist pattern to expose portions of the material layer, and etching the exposed portions of the material layer.

[0077] The substrate may be, for example, a silicon wafer, a glass substrate, or a polymer substrate. The material layer is a material to be finally patterned, and may be, for example, a metal layer such as aluminum, copper, etc., a semiconductor layer such as silicon, or an insulating layer such as silicon oxide, silicon nitride, etc. The material layer may be formed, for example, by a chemical vapor deposition method.

[0078] The hard mask composition may be prepared in the form of a solution as described above and applied by a spin-on coating method. In this case, the thickness of the hard mask composition is not particularly limited, but may be, for example, 50 to 200,000 Å.

[0079] The step of heat treating the hard mask composition may be performed for 10 seconds to 1 hour at, for example, 100° C. to 1,000° C. For example, the step of heat treating the hard mask composition may include a plurality of heat treatment steps, for example, a first heat treatment step and a second heat treatment step.

[0080] In one embodiment, the step of heat treating the hard mask composition may include a heat treatment step performed at, for example, 100° C. to 1000° C. for 10 seconds to 1 hour. For example, the heat treatment step may be performed in an air atmosphere or a nitrogen atmosphere, or in an atmosphere having an oxygen concentration of 1% by weight or less.

[0081] In one embodiment, the step of heat treating the hard mask composition includes a first heat treatment step performed at, for example, 100° C. to 1,000° C., for example, 100° C. to 800° C., for example, 100° C. to 500° C., for example, 150° C. to 400° C., for example, 30 seconds to 1 hour, for example, 30 seconds to 30 minutes, for example, 30 seconds to 10 minutes, for example, 30 seconds to 5 minutes.

[0082] Also, it may include a second heat treatment step successively performed at, for example, 100° C. to 1,000° C., for example, 300° C. to 1,000° C., for example, 500° C. to 1,000° C., for example, 500° C. to 600° C., for example, 30 seconds to 1 hour, for example, 30 seconds to 30 minutes, for example, 30 seconds to 10 minutes, for example, 30 seconds to 5 minutes. As an example, the first and second heat treatment steps may be performed in an air atmosphere or a nitrogen atmosphere, or may be performed in an atmosphere having an oxygen concentration of 1% by mass or less.

[0083] At least one of the steps of heat treating the hard mask composition is performed at a high temperature of 200° C. or more, so that the hard mask composition can exhibit high etching resistance against etching gases and chemical solutions to which the hard mask composition is exposed in subsequent processes including an etching process.

[0084] In one embodiment, forming the hard mask layer may include an ultraviolet / visible (UV / Vis) curing step and / or a near infrared (NIR) curing step.

[0085] In an embodiment, the step of forming the hard mask layer may include at least one of the first heat treatment step, the second heat treatment step, the ultraviolet-visible light (UV / Vis) curing step, and the near-infrared (NIR) curing step, or may include two or more of these steps consecutively.

[0086] In one embodiment, the method may further include forming a silicon-containing thin film layer on the hard mask layer, the silicon-containing thin film layer being formed of a material such as, for example, SiCN, SiOC, SiON, SiOCN, SiC, SiO, and / or SiN.

[0087] In one embodiment, before forming the photoresist layer, a bottom anti-reflective layer (BARC) may be further formed on the silicon-containing thin film layer or the hard mask layer.

[0088] In one embodiment, the step of exposing the photoresist layer can be performed using, for example, ArF, KrF, EUV, etc. After the exposure, a heat treatment process can be performed at 100 to 700°C.

[0089] In one embodiment, the step of etching the exposed portions of the material layer may be performed by dry etching using an etching gas, such as N2 / O2, CHF3, CF4, Cl2, BCl3, and mixtures thereof.

[0090] The etched material layer may be formed into a variety of patterns, including metal patterns, semiconductor patterns, insulating patterns, and the like, and may be applied to various patterns within, for example, a semiconductor integrated circuit device. EXAMPLES

[0091] The above-mentioned embodiments of the present invention will be described in more detail with reference to the following examples, which are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0092] [Synthesis of Compounds] (Synthesis Example 1) A flask was charged with 38.8 g (0.2 mol) of 9-phenanthrol, 7.7 g (0.04 mol) of 4-chlorobenzenesulfonic acid, and 200 mL of 1,2-dichlorobenzene, and a Dean-Stark trap was installed and the mixture was stirred for 12 hours at 180° C. After the reaction was completed, the product was cooled to room temperature, the solvent was removed under reduced pressure, and the product was purified using column chromatography to obtain compound 1a represented by the following chemical formula 1a.

[0093] [ka]

[0094] 37.0g (0.1mol) of compound 1a and 28.1g (0.2mol) of benzoyl chloride were dissolved in 300mL of 1,2-dichloroethane, and then 26.7g (0.2mol) of aluminum chloride was gradually added dropwise over 20 minutes while stirring at room temperature. After the reaction was completed, the product was added to 500mL of cooled distilled water (DIW), and the organic layer was extracted twice with 200mL of dichloromethane (DCM). The organic layer was washed with 100mL of NaHCO3 aqueous solution and 100mL of distilled water (DIW), and the solvent was removed under reduced pressure to obtain compound 1b represented by the following chemical formula 1b.

[0095] [ka]

[0096] 28.9g (0.05mol) of compound 1b was dissolved in 300mL of methanol / dichloromethane (1:1 volume ratio mixture), then 4.2g (0.11mol) of NaBH4 was added and stirred at room temperature for 8 hours. After the reaction was completed, 200mL of dichloromethane was added to the product, and the organic layer was washed with 100mL of distilled water (DIW), 100mL of NaHCO3 aqueous solution, and 200ml of distilled water (DIW) (100mL x 2 times) in that order. The organic solvent was then removed under reduced pressure to obtain compound 1 represented by the following chemical formula 1-7.

[0097] [ka]

[0098] (Synthesis Example 2) Compound 2 represented by the following chemical formula 1-8 was obtained in the same manner as in Synthesis Example 1, except that 2-naphthoyl chloride was used in place of benzoyl chloride in the same molar amount (0.2 mol).

[0099] [ka]

[0100] (Synthesis Example 3) Compound 3 represented by the following chemical formula 1-9 was obtained in the same manner as in Synthesis Example 2, except that 19.4 g (0.1 mol) of 9-phenanthrol and 19.4 g (0.1 mol) of 2-phenanthrol were used instead of 38.8 g (0.2 mol) of 9-phenanthrol.

[0101] [ka]

[0102] (Synthesis Example 4) Compound 4 represented by the following chemical formula 1-10 was obtained in the same manner as in Synthesis Example 2, except that 19.4 g (0.1 mol) of 9-phenanthrol and 24.4 g (0.1 mol) of 2-hydroxytriphenylene were used instead of 38.8 g (0.2 mol) of 9-phenanthrol.

[0103] [ka]

[0104] (Synthesis Example 5) Compound 5 represented by the following chemical formula 1-11 was obtained in the same manner as in Synthesis Example 2, except that 4-hydroxypyrene was used in place of 9-phenanthrol in the same molar amount (0.2 mol).

[0105] [ka]

[0106] (Synthesis Example 6) Compound 6 represented by the following chemical formula 1-12 was obtained in the same manner as in Synthesis Example 2, except that 21.8 g (0.1 mol) of 1-hydroxypyrene and 21.8 g (0.1 mol) of 4-hydroxypyrene were used instead of 38.8 g (0.2 mol) of 9-phenanthrol.

[0107] [ka]

[0108] (Synthesis Example 7) Compound 7 represented by the following chemical formula 1-13 was obtained in the same manner as in Synthesis Example 2, except that 21.8 g (0.1 mol) of 1-hydroxypyrene and 21.8 g (0.1 mol) of 4-hydroxypyrene were used instead of 38.8 g (0.2 mol) of 9-phenanthrol, and the equivalent amount of 2-naphthoyl chloride was changed from 38.13 g (0.2 mol) to 62.9 g (0.33 mol).

[0109] [ka]

[0110] (Comparative Synthesis Example 1) 28.83g (0.2mol) of 1-naphthol, 41.4g (0.15mol) of benzoperylene and 12.08g (0.4mol) of paraformaldehyde were put into a three-neck flask, 0.57g (0.003mol) of p-toluenesulfonic acid monohydrate was dissolved in 163g of propylene glycol monomethyl ether acetate (PGMEA), and the mixture was stirred at 60°C for 18 hours to allow the polymerization reaction to proceed. After the reaction was completed, the product was added to 40g of distilled water and 400g of methanol, stirred vigorously, and then allowed to stand. Next, the supernatant was removed and the precipitate was dissolved in 80g of propylene glycol monomethyl ether acetate (PGMEA), and then stirred vigorously using 320g of methanol, and then allowed to stand. The washing process was repeated twice more, and the washed polymer was dissolved in 80 g of propylene glycol monomethyl ether acetate (PGMEA), and the methanol and distilled water remaining in the solution were removed under reduced pressure. 1 L of tetrahydrofuran (THF) was added to the obtained concentrated solution, and the solution was gradually dropped into a beaker containing 1 L of stirred hexane to form a precipitate, thereby obtaining comparative compound A represented by the following chemical formula A. Comparative compound A has a weight average molecular weight (Mw) of 4,000 g / mol and a polydispersity (PD) of 1.75.

[0111] [ka]

[0112] (Comparative Synthesis Example 2) Comparative compound B represented by the following chemical formula B was obtained in the same manner as in Synthesis Example 2, except that 28 g (0.1 mol) of benzoperylene was used instead of compound 1a.

[0113] [ka]

[0114] [Preparation of hard mask composition] Example 1 3.5 g of Compound 1 obtained in Synthesis Example 1 was dissolved in 10 g of a solvent in which propylene glycol methyl ether acetate and cyclohexanone were mixed in a volume ratio of 7:3, and then filtered through a syringe filter to prepare a hard mask composition.

[0115] Example 2 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 2 was used instead of Compound 1.

[0116] Example 3 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 3 was used instead of Compound 1.

[0117] Example 4 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 4 was used instead of Compound 1.

[0118] Example 5 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 5 was used instead of Compound 1.

[0119] Example 6 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 6 was used instead of Compound 1.

[0120] Example 7 A hard mask composition was prepared in the same manner as in Example 1, except that Compound 7 was used instead of Compound 1.

[0121] Comparative Example 1 A hard mask composition was prepared in the same manner as in Example 1, except that Comparative Compound A was used instead of Compound 1.

[0122] Comparative Example 2 A hard mask composition was prepared in the same manner as in Example 1, except that Comparative Compound B was used instead of Compound 1.

[0123] [Evaluation 1: Etching resistance evaluation] The hard mask compositions according to Examples 1 to 7 and Comparative Examples 1 to 2 were applied onto silicon wafers, and then heat-treated on a hot plate at 400° C. for 2 minutes to form hard mask layers with a thickness of 4,000 Å. The hard mask layers were dry-etched using a CFx mixed gas and an N2 / O2 mixed gas, respectively, and the thicknesses of the hard masks before and after etching were measured using a thin film thickness meter manufactured by K-MAC, and the bulk etch rate was calculated according to Equation 1 below. The results are shown in Table 1 below.

[0124]

number

[0125] [Table 1]

[0126] Referring to Table 1, it can be seen that the etching rate of the hard mask layer formed from the hard mask composition according to the embodiment is relatively small and has excellent etching resistance compared to the hard mask layer formed from the hard mask composition according to the comparative example.

[0127] [Evaluation 2: Planarization and gap-fill characteristics evaluation] The hard mask compositions according to Examples 1 to 7 and Comparative Examples 1 to 2 were applied to the wafer on which the pattern was formed, and then heat-treated on a hot plate at 400° C. for 2 minutes to form a hard mask layer having a thickness of 2,000 Å. FIG. 1 is a reference diagram showing an example of the step of the hard mask layer to explain the method of evaluating the planarization characteristics. The planarization characteristics were calculated by measuring the average value (h1) of the thin film thickness measured at three arbitrary points on the substrate where no pattern was formed and the average value (h2) of the thin film thickness measured at three arbitrary points on the substrate where a pattern was formed using a thin film thickness meter manufactured by K-MAC, and calculating the step (|h1-h2|). The smaller the step (|h1-h2|), the better the planarization characteristics. The gap-fill characteristics were evaluated by observing the cross section of the pattern using a scanning electron microscope (SEM) to observe the presence or absence of voids, and the results are shown in Table 2 below.

[0128] [Table 2]

[0129] Referring to Table 2, the hard mask layers formed from the hard mask compositions according to Comparative Examples 1 and 2 had a relatively large difference between h1 and h2, and voids were observed in the patterns. That is, it can be seen that the hard mask layers formed from the compositions according to Comparative Examples 1 and 2 had poor planarization characteristics and poor gap-fill characteristics. In contrast, the hard mask layers formed from the hard mask compositions according to Examples 1 to 7 had a relatively small difference between h1 and h2, and no voids were observed in the patterns. That is, it can be seen that the hard mask layers formed from the compositions according to the Examples had excellent planarization characteristics and gap-fill characteristics.

[0130] Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the invention defined in the claims also fall within the scope of the present invention.

Claims

1. A hard mask composition comprising a compound represented by the following Chemical Formula 1 and a solvent: 【Chemistry 1】 In the above chemical formula 1, Ar １ and Ar ２ are each independently an aromatic hydrocarbon ring having 6 to 30 carbon atoms, X １ and X ２ each independently represents a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 carbon atoms, R １ and R ２ each independently represents a deuterium atom, a hydroxyl group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a combination thereof; n1 and n2 each independently represent an integer from 0 to 4, and n1+n2 represents an integer of 1 or more; m1 is Ar １ is an integer equal to or greater than 0, with the upper limit being the number of possible replacements for m2 is Ar ２ is an integer of 0 or more, with the upper limit being the number that can be replaced by

2. Ar of Formula 1 １ and Ar ２ is each independently any one of the structures listed in Group 1 below: 【Chemistry 2】

3. Ar of Formula 1 １ and Ar ２ is each independently any one selected from the structures listed in Group 1-1 below: 【Chemistry 3】

4. X in Formula 1 １ and X ２ is independently any one of the moieties selected from the substituted or unsubstituted structures listed in Group 2 below: 【Chemistry 4】

5. X in Formula 1 １ and X ２ is independently any one of the moieties selected from the substituted or unsubstituted structures listed in Group 2-1 below: 【Chemistry 5】

6. Ar of Formula 1 １ and Ar ２ are each independently one of the moieties selected from the structures listed in Group 1-2 below, １ and X ２ are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group; and n1 and n2 are each independently 1 or 2. 【Chemistry 6】

7. The hard mask composition of claim 1 , wherein the compound represented by Formula 1 has an asymmetric structure.

8. The hard mask composition according to claim 1, wherein the compound represented by Formula 1 is at least one of compounds represented by the following Formulas 1-1 to 1-6: 【Chemistry 7】 In the above Chemical Formula 1-1 to Chemical Formula 1-6, X １ and X ２ are each independently a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted pyrenyl group, or a substituted or unsubstituted triphenylenyl group; n1 and n2 are an integer between 0 and 4, and n1+n2 is an integer between 1 and 4; R １ and R ２ each independently represents a deuterium atom, a hydroxyl group, a halogen atom, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a combination thereof; m1 is Ar １ is an integer equal to or greater than 0, with the upper limit being the number of possible replacements for m2 is Ar ２ is an integer of 0 or more, with the upper limit being the number that can be replaced by

9. 9. The hard mask composition of claim 8, wherein n1 and n2 in Formulae 1-1 to 1-6 are each independently 1 or 2.

10. 2. The hard mask composition of claim 1, wherein the compound has a molecular weight of 500 g / mol to 10,000 g / mol.

11. The hard mask composition of claim 1 , wherein the compound is included in an amount of 0.1% by weight to 30% by weight based on the total weight of the hard mask composition.

12. 2. The hard mask composition of claim 1, wherein the solvent comprises at least one selected from the group consisting of propylene glycol, propylene glycol diacetate, methoxypropanediol, diethylene glycol, diethylene glycol butyl ether, tri(ethylene glycol) monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, methylpyrrolidone, methylpyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

13. A hardmask layer comprising a cured product of the hardmask composition according to any one of claims 1 to 12.

14. providing a layer of material over a substrate; applying a hard mask composition according to any one of claims 1 to 12 onto the material layer; heat-treating the hard mask composition to form a hard mask layer; forming a photoresist layer over the hard mask layer; exposing and developing the photoresist layer to form a photoresist pattern; selectively removing the hard mask layer using the photoresist pattern to expose portions of the material layer; and etching exposed portions of the layer of material; A pattern forming method comprising the steps of:

15. The method of claim 14, wherein the step of forming the hard mask layer comprises a step of performing a heat treatment at a temperature of 100° C. to 1,000° C.

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