Hardmask composition, hardmask layer, and method of forming patterns

Abstract

To provide a hardmask composition that can be effectively applied to a hardmask layer.SOLUTION: A hardmask composition comprises a polymer represented by Chemical Formula 1 and a solvent. The definitions of Chemical Formula 1 are 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 comprising a cured product of the hard mask composition, and a patterning method using the hard mask composition. [Background technology]

[0002] Recently, the semiconductor industry has been evolving from patterns of hundreds of nanometers to ultrafine technology with patterns of several to tens of nanometers. To realize such ultrafine technology, effective lithographic techniques are essential.

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

[0004] In recent years, as the size of the pattern to be formed decreases, it has become difficult to form a fine pattern with a good profile using the typical lithographic techniques described above. For this reason, research has been conducted into a technology for forming a fine pattern by forming an auxiliary layer, called a hard mask layer, between the material layer to be etched and the photoresist layer. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Korean Patent Publication No. 10-2019-0059611 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 that can be effectively applied to a hard mask layer.

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

[0008] It is still another object of the present invention to provide a pattern formation method using the hard mask composition. [Means for solving the problem]

[0009] A hard mask composition according to one embodiment of the present invention includes a polymer represented by the following Chemical Formula 1 and a solvent:

[0010] [ka]

[0011] In the above chemical formula 1, Ar 1 ~Ar 6 are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 20 carbon atoms, X 1 ~X 6 are each independently a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 20 carbon atoms, L 1 and L 2 are each independently a divalent organic group, n is an integer from 1 to 100.

[0012] Ar in the above chemical formula 1 1 ~Ar 6 are preferably each independently a group containing at least one of the substituted or unsubstituted moieties represented by Group 1 below.

[0013] [ka]

[0014] X in the above chemical formula 1 1 ~X 6 are preferably each independently a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 2 below.

[0015] [ka]

[0016] L in the above chemical formula 1 1 and L 2 are preferably each independently at least one group selected from the group consisting of groups represented by Chemical Formula 2 to Chemical Formula 5 below.

[0017] [ka]

[0018] In the above chemical formulas 2 to 5, M 1 ~M 4 are each independently a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 3 below, p1 to p3 and q1 to q3 each independently represent an integer of 0 to 4; p4 is an integer from 1 to 5; * is the connection point:

[0019] [ka]

[0020] Among the above group 3, L a ~L c each independently represents a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms, or a combination thereof; Z a and Z b are each independently -O-, -S-, -SO2-, -C(=O)-, or -NR a -(where R a is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms), s1 and s2 are each independently 0 or 1; t is an integer from 0 to 4.

[0021] L in the above chemical formula 1 1 and L 2 are preferably each independently at least one selected from the group consisting of groups represented by the following chemical formulas 7 to 13.

[0022] [ka]

[0023] In the above chemical formulas 7 to 13, * indicates a connection point.

[0024] The polymer is preferably at least one selected from the group consisting of polymers represented by the following chemical formulas 1-1 to 1-3.

[0025] [ka]

[0026] In the above chemical formulas 1-1 to 1-3, R 1 ~R 6 are each independently a deuterium atom, a hydroxy group, a substituted or unsubstituted alkoxy group having 1 to 5 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, or a combination thereof; y1 to y6 each independently represent an integer from 1 to 4; Each n is independently an integer of 1 to 100.

[0027] The weight average molecular weight of the polymer is preferably 1,000 g / mol to 10,000 g / mol.

[0028] The polymer 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, N-methyl-2-pyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

[0030] According to another embodiment of the present invention, there is provided a hard mask layer comprising a cured product of the hard mask composition described above.

[0031] According to yet another embodiment of the present invention, there is provided a pattern formation method including the steps of: forming 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 a portion of the material layer; and etching the exposed portion 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. [Effects of the Invention]

[0033] According to the present invention, a hard mask composition is provided that can be effectively applied to a hard mask layer. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 1 is a diagram schematically showing a cross section of a hard mask layer for explaining a method for evaluating planarization characteristics. DETAILED DESCRIPTION OF THE INVENTION

[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 halogen atom (F, Br, Cl, or I), a hydroxy group, an alkoxy 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 carboxy group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphate 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, or a substituted or unsubstituted alkyl group having 2 to 20 carbon atoms. It means that the alkyl group is substituted with a substituent selected from an alkynyl group having 6 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 31 carbon atoms, an arylaryl group having 9 to 33 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 in a substituted halogen atom (F, Br, Cl, or I), a hydroxy 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 carboxy group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphate group or a salt thereof, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, an alkynyl group having 2 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 31 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, or a heterocyclic group having 2 to 30 carbon atoms can be bonded (condensed) to form a ring.

[0038] Unless otherwise defined in this specification, the term "aromatic hydrocarbon ring" refers to a group having one or more aromatic hydrocarbon rings, and includes not only non-fused aromatic hydrocarbon rings and fused aromatic hydrocarbon rings, but also forms in which aromatic hydrocarbon rings are linked by a single bond, forms of non-aromatic fused rings to which aromatic hydrocarbon rings 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 anthryl 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 fused form of a combination thereof.

[0040] Unless otherwise defined herein, "combination" means blending or copolymerization.

[0041] Unless otherwise defined herein, the term "polymer" may include both oligomers and polymers.

[0042] Unless otherwise defined in this specification, the "weight average molecular weight" is measured by dissolving a powder sample in tetrahydrofuran (THF) and then using a 1200 series gel permeation chromatography (GPC) manufactured by Agilent Technologies (using an LF-804 column manufactured by Resonac Corporation and polystyrene standards manufactured by Resonac Corporation).

[0043] The semiconductor industry continues to demand smaller chip sizes. To meet this demand, the line width of resists patterned using lithography techniques must be reduced to several tens of nanometers. Therefore, the height that can be tolerated by the line width of the resist pattern is limited, and the resist may not have sufficient resistance during the etching step. To address this, an auxiliary layer known as a hard mask layer may be used between the material layer to be etched and the photoresist layer. Such a 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 must be etch-resistant and heat-resistant to withstand the etching process required for pattern transfer.

[0044] Furthermore, in order to realize a fine pattern of a photoresist, it is necessary to form multiple patterns, and gap-filling properties are required to fill the fine pattern with the composition without gaps.Furthermore, when the substrate to be processed has steps or when patterned and unpatterned regions exist on the same wafer, planarization properties are required to form a flat surface of the hard mask layer.

[0045] Conventional hard mask layers have been formed using chemical or physical vapor deposition methods, but these methods have problems with large equipment scales, high process costs, and reduced economic viability. Therefore, a technology for forming hard mask layers using a spin coating method has recently been developed. The spin coating method is easier to process than conventional methods, and the resulting hard mask layers have superior gap-fill and planarization properties.

[0046] However, a hard mask layer formed by spin coating has a problem of slightly reduced etching resistance. Therefore, a hard mask composition that can be applied to spin coating and a hard mask layer formed therefrom are required to have etching resistance equivalent to that of a hard mask layer formed by chemical or physical vapor deposition.

[0047] Therefore, research has been conducted to increase the carbon content of hard mask compositions in order to improve the etching resistance of hard mask layers. However, as the carbon content of the polymer contained in the hard mask composition increases, the solubility in solvents tends to decrease. Therefore, it is necessary to increase the carbon content of the polymer contained in the hard mask composition to improve the etching resistance of the hard mask layer formed therefrom, while also ensuring that the polymer has good solubility in solvents.

[0048] The hard mask composition according to one embodiment of the present invention includes a polymer having a high carbon content but a low molecular weight, thereby providing excellent gap-filling properties for fine patterns. Furthermore, the polymer includes a linking group with high fluidity, thereby providing excellent solubility in a solvent, and thus providing excellent planarization properties for a hard mask layer formed from the composition.

[0049] Specifically, a hard mask composition according to one embodiment of the present invention includes a polymer represented by the following Chemical Formula 1 and a solvent:

[0050] [ka]

[0051] In the above chemical formula 1, Ar 1 ~Ar 6 are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 20 carbon atoms, X 1 ~X 6 are each independently a substituted or unsubstituted aromatic hydrocarbon ring group having 6 to 20 carbon atoms, L 1 and L 2 are each independently a divalent organic group, n is an integer from 1 to 100.

[0052] The polymer has an aromatic hydrocarbon ring, X 1 , X 2 , Ar 1 , and Ar 2 and a moiety containing X 5 , X 6 , Ar 5 , and Ar 6 By including a moiety containing L at both ends, the gap fill property of the composition and the heat resistance of the hard mask layer formed from the composition can be improved. 1 and L 2 By including a flowable linking group represented by the formula (I), the polymer has excellent solubility in a solvent and excellent coating properties, and therefore the planarization properties of a hard mask layer formed from the composition can be improved.

[0053] In one embodiment of the present invention, Ar in the above formula 1 1 ~Ar 6 are each independently a ring containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 1 below, such as, but not limited to, a substituted or unsubstituted benzene ring, a substituted or unsubstituted naphthalene ring, or a substituted or unsubstituted pyrene ring.

[0054] [ka]

[0055] In one embodiment of the present invention, X in the above formula 1 2 ~X 5 are each independently at least one group containing a substituted or unsubstituted moiety selected from Group 2 below, and are, for example, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted phenanthrenylene group, a substituted or unsubstituted anthracenylene group, a substituted or unsubstituted pyrenylene group, or a combination thereof, and may be, for example, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted pyrenylene group, or a combination thereof, but are not limited to these.

[0056] X in the above chemical formula 1 1 and X 6 are each independently a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 2 below, and examples thereof include a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted pyrenyl group, or a combination thereof, and may be, for example, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted pyrenyl group, or a combination thereof, but are not limited to these.

[0057] [ka]

[0058] X in the above chemical formula 1 1 ~X 6The moieties used in the formula (1) may each independently be substituted or unsubstituted with a deuterium atom, a halogen atom, an amino group, a hydroxy group, 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 cycloalkenyl group having 3 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a combination thereof.

[0059] In one embodiment of the present invention, L in the above Chemical Formula 1 1 and L 2 are preferably each independently at least one of the groups represented by Chemical Formula 2 to Chemical Formula 5 below.

[0060] [ka]

[0061] In the above chemical formula 2, M 1 is a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 3 below. Examples include a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted anthracenylene group, a substituted or unsubstituted phenanthrylene group, a substituted or unsubstituted pyrenylene group, or a combination thereof, and may be, for example, a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, or a combination thereof, but are not limited to these.

[0062] In the above chemical formulas 3 and 4, M 2 ~M 4are each independently a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 3 below, and examples thereof include a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthryl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted pyrenyl group, or a combination thereof, and may be, for example, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, or a combination thereof, but are not limited to these.

[0063] [ka]

[0064] Among the above group 3, L a ~L c are each independently a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms, or a combination thereof, and may be, for example, a single bond, a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms, or a combination thereof, but are not limited to these.

[0065] In one embodiment of the present invention, Z in Group 3 above a and Z b are each independently -O-, -S-, -SO2-, -C(=O)-, or -NR a -(where R a is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms), and can be, for example, —O— or —S—, but is not limited to these.

[0066] In one embodiment of the present invention, s1 and s2 are each independently 0 or 1, and t can be one of integers from 0 to 4, but is not limited thereto.

[0067] In one embodiment of the present invention, in the above Chemical Formulas 2 to 4, p1 to p3 and q1 to q3 are each independently an integer of 0 to 4, for example, an integer of 0 to 3, such as 0 or 1, but are not limited thereto.

[0068] In one embodiment of the present invention, in the above chemical formula 5, p4 is one of integers of 1 to 5, for example, one of integers of 1 to 3, for example, 1 or 2, but is not limited thereto.

[0069] In the above chemical formulas 2 to 5, * indicates a linking point.

[0070] As an example, L in the above chemical formula 1 1 and L 2 may each independently be at least one of groups represented by the following chemical formulas 7 to 13.

[0071] [ka]

[0072] In the above chemical formulas 7 to 13, * indicates a linking point.

[0073] In one embodiment of the present invention, in the above Chemical Formula 1, n is an integer of 1 to 100, and the average value of n is 1 to 10. For example, n is an integer of 1 to 50, for example, an integer of 1 to 40, for example, an integer of 1 to 30. Furthermore, the average value of n can be, for example, 1 to 10, for example, 1 to 7, or for example, 1 to 5, but is not limited thereto. The above average value of n refers to the value obtained by dividing the weight average molecular weight of the polymer by the molecular weight of the structural unit repeated within the polymer.

[0074] In one embodiment of the present invention, the polymer may be at least one of polymers represented by the following chemical formulas 1-1 to 1-3.

[0075] [ka]

[0076] In the above chemical formulas 1-1 to 1-3, R 1 ~R 6 are each independently a deuterium atom, a hydroxy group, a substituted or unsubstituted alkoxy group having 1 to 5 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, or a combination thereof, and may be, for example, a deuterium atom, a hydroxy group, a substituted or unsubstituted alkoxy group having 1 to 5 carbon atoms, or a combination thereof, but are not limited to these.

[0077] In the above chemical formulas 1-1 to 1-3, y1 to y6 are each independently one of integers 1 to 4, for example, 1 to 3, such as 1 or 2, but are not limited thereto.

[0078] In the above Chemical Formulas 1-1 to 1-3, the average value of n can be independently 1 to 10, for example, 1 to 7, for example, 1 to 5, but is not limited to these.

[0079] The polymer may have a weight-average molecular weight of 1,000 g / mol to 10,000 g / mol, for example, 1,000 g / mol to 9,500 g / mol, for example, 1,000 g / mol to 9,000 g / mol, for example, 1,200 g / mol to 9,000 g / mol, for example, 1,200 g / mol to 8,000 g / mol, for example, 1,500 g / mol to 8,000 g / mol, for example, 1,500 g / mol to 7,000 g / mol, for example, 1,500 g / mol to 6,000 g / mol, for example, 1,500 g / mol to 5,000 g / mol, or for example, 1,500 g / mol to 3,000 g / mol, but is not limited thereto. By having the weight average molecular weight within the above range, the carbon content and solubility in a solvent of the hard mask composition containing the polymer can be controlled, and thereby a hard mask layer exhibiting optimal gap filling and planarization properties can be produced.

[0080] The polymer may be a commercially available product or a synthetic product. When synthesizing, it can be carried out by appropriately referring to a conventionally known synthesis method. More specifically, it can be easily synthesized by a person skilled in the art by referring to the synthesis method described in the examples.

[0081] The polymer may be included in an amount of 0.1% by mass to 30% by mass based on the total mass of the hard mask composition. The polymer content may be, but is not limited to, 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, 1.5% by mass to 25% by mass, or for example, 2% by mass to 20% by mass based on the total mass of the hard mask composition. By including the polymer in the above range, the thickness, surface roughness, and degree of planarization of the hard mask can be easily adjusted.

[0082] The hard mask composition according to one embodiment of the present invention may include a solvent, such as, but 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, N-methyl-2-pyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate. The solvent is not particularly limited as long as it has sufficient solubility and / or dispersibility in the polymer.

[0083] The hard mask composition of the present invention may further include additives such as surfactants, crosslinking agents, thermal acid generators, and plasticizers.

[0084] Examples of surfactants that can be used include, but are not limited to, fluoroalkyl compounds, alkylbenzenesulfonates, alkylpyridinium salts, polyethylene glycols, and quaternary ammonium salts.

[0085] Examples of crosslinking agents include melamine-based agents, substituted urea-based agents, and polymers thereof. A crosslinking agent having at least two crosslink-forming substituents is preferred, and compounds such as methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, and butoxymethylated thiourea can be used.

[0086] Furthermore, a crosslinking agent having high heat resistance can be used as the crosslinking agent. As the crosslinking agent having high heat resistance, a compound containing a crosslink-forming substituent having an aromatic ring (e.g., a benzene ring or a naphthalene ring) in the molecule can be used.

[0087] Examples of thermal acid generators 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 other organic sulfonic acid alkyl esters.

[0088] According to another embodiment of the present invention, there is provided a hard mask layer comprising a cured product of the hard mask composition described above.

[0089] A method for forming a pattern using the above-described hard mask composition will now be described.

[0090] A pattern formation method according to one embodiment of the present invention includes the steps of forming a material layer on a substrate, applying a hard mask composition containing the above-described polymer and a solvent onto 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 a portion of the material layer, and etching the exposed portion of the material layer.

[0091] The substrate used may be, for example, a silicon wafer, a glass substrate, or a polymer substrate. The material layer is the material to be finally patterned, and may be, for example, a metal layer such as aluminum or copper, a semiconductor layer such as silicon, or an insulating layer such as silicon oxide or silicon nitride. The material layer may be formed, for example, by chemical vapor deposition.

[0092] The hard mask composition may be prepared in the form of a solution and applied by spin coating, as described above. The thickness of the hard mask composition is not particularly limited, but may be, for example, greater than 0 Å and less than or equal to 200,000 Å.

[0093] The step of heat-treating the hard mask composition may be performed for 10 seconds to 1 hour at a temperature of 100° C. to 1,000° C. For example, the step of heat-treating the hard mask composition may include multiple heat-treatment steps, such as a first heat-treatment step and a second heat-treatment step.

[0094] In one embodiment of the present invention, the step of heat-treating the hard mask composition may include a single heat-treatment step performed at a temperature of 100° C. to 1,000° C. for 10 seconds to 1 hour. For example, the heat-treatment step may be performed in an air or nitrogen atmosphere, or in an atmosphere with an oxygen concentration of 1 wt % or less.

[0095] In one embodiment of the present invention, the step of heat-treating the hard mask composition includes a first heat-treatment step performed at a temperature of, 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 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.

[0096] Furthermore, the method may include a successive secondary heat treatment step that is carried out for 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, under temperature conditions of, 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, the primary and secondary heat treatment steps may be carried out in an air atmosphere or a nitrogen atmosphere, or may be carried out in an atmosphere with an oxygen concentration of 1% by mass or less.

[0097] By performing at least one of the steps of heat treating the hard mask composition at a high temperature of 200°C or higher, the hard mask composition can exhibit high etching resistance that can withstand etching gases and chemical solutions to which the hard mask composition is exposed in subsequent processes, including etching processes.

[0098] In one embodiment of the present invention, the step of forming a hard mask layer may include a UV / visible curing step and / or a near-infrared curing step.

[0099] In one embodiment of the present invention, the step of forming the hard mask layer may include at least one of a first heat treatment step, a second heat treatment step, a UV / visible curing step, and a near-infrared curing step, or may include two or more of these steps consecutively.

[0100] In some embodiments, the method may further include forming a silicon-containing thin film layer on the hard mask layer. The silicon-containing thin film layer may be formed of a material such as SiCN, SiOC, SiON, SiOCN, SiC, SiO, and / or SiN.

[0101] In one embodiment of the present invention, before the step of forming the photoresist layer, a bottom anti-reflective coating (BARC) may be further formed on the silicon-containing thin film layer or on the hard mask layer.

[0102] In one embodiment of the present invention, the step of exposing the photoresist layer can be performed using, for example, an ArF excimer laser, a KrF excimer laser, or extreme ultraviolet (EUV) rays, etc. After the exposure, a heat treatment process can be performed at a temperature of 100°C to 700°C.

[0103] In one embodiment of the present invention, etching the exposed portions of the material layer can be performed by dry etching using an etching gas, such as N2 / O2, CHF3, CF4, Cl2, BCl3, and mixtures thereof.

[0104] The etched material layer can be formed in multiple patterns, which can be diverse, such as metal patterns, semiconductor patterns, insulating patterns, etc., and can be applied as various patterns within a semiconductor integrated circuit device, for example. [Example]

[0105] The above-described embodiments of the present invention will be described in more detail with reference to the following examples, which are provided for illustrative purposes only and are not intended to limit the scope of the present invention.

[0106] (Polymer synthesis) (Synthesis Example 1) A flask was charged with 1.8 mol of 9,9-bis(6-hydroxy-2-naphthyl)fluorene, 1 mol of 4,4′-oxybis[4-(methoxymethyl)benzene], 123 g of propylene glycol monomethyl ether acetate (PGMEA), and 0.5 g of diethyl sulfate, and the mixture was stirred at 100°C to carry out a polymerization reaction.

[0107] After the polymerization reaction was completed, the intermediate product was gradually cooled to room temperature and added to 40 g of distilled water and 400 g of methanol, followed by vigorous stirring and settling. The supernatant was removed, and the precipitate was dissolved in 80 g of cyclohexanone. 320 g of methanol was then added, followed by vigorous stirring and settling (first step). The resulting supernatant was again removed, and the precipitate was dissolved in 80 g of cyclohexanone (second step). The first and second steps constituted one purification step, and this purification step was carried out a total of three times. The purified polymer was dissolved in 80 g of cyclohexanone, and the remaining methanol and distilled water were removed under reduced pressure to obtain the polymer represented by the following chemical formula 1-4 (Mw: 3,000 g / mol).

[0108] [ka]

[0109] (Synthesis Example 2) A polymer represented by the following chemical formula 1-5 (Mw: 3,400 g / mol) was obtained in the same manner as in Synthesis Example 1 above, except that 1.6 mol of 9,9-bis(3,4-dihydroxyphenyl)fluorene was used instead of 1.8 mol of 9,9-bis(6-hydroxy-2-naphthyl)fluorene and 1 mol of 4,4'-oxybis[4-(methoxymethyl)benzene] were used.

[0110] [ka]

[0111] (Synthesis Example 3) 1.8 mol of 9,9-bis(6-hydroxy-2-naphthyl)fluorene, 1 mol of 1,4-bis(methoxymethyl)benzene, 123 g of propylene glycol monomethyl ether acetate (PGMEA), and 0.5 g of diethyl sulfate were placed in a flask and stirred at 100°C to carry out a polymerization reaction.

[0112] After the polymerization reaction was completed, the intermediate product was gradually cooled to room temperature and added to 40 g of distilled water and 400 g of methanol, followed by vigorous stirring and settling. The supernatant was removed, and the precipitate was dissolved in 80 g of cyclohexanone. 320 g of methanol was then added, followed by vigorous stirring and settling (first step). The resulting supernatant was removed again, and the precipitate was dissolved in 80 g of cyclohexanone (second step). The first and second steps were considered as one purification step, and this purification step was carried out a total of three times. The purified polymer was dissolved in 80 g of cyclohexanone, and the remaining methanol and distilled water were removed under reduced pressure to obtain the polymer represented by the following chemical formula 1-6 (Mw: 3,000 g / mol).

[0113] [ka]

[0114] (Comparative Synthesis Example 1) A flask was charged with 1 mol of 9,9-bis(6-hydroxy-2-naphthyl)fluorene, 1 mol of 4,4'-oxybis[4-(methoxymethyl)benzene], 123 g of propylene glycol monomethyl ether acetate (PGMEA), and 0.5 g of diethyl sulfate, and the mixture was stirred at 100°C to carry out a polymerization reaction.

[0115] After the polymerization reaction was completed, the intermediate product was gradually cooled to room temperature and added to 40 g of distilled water and 400 g of methanol, followed by vigorous stirring and settling. The supernatant was removed, and the precipitate was dissolved in 80 g of cyclohexanone. 320 g of methanol was then added, followed by vigorous stirring and settling (first step). The resulting supernatant was again removed, and the precipitate was dissolved in 80 g of cyclohexanone (second step). The first and second steps constituted one purification step, and this purification step was carried out a total of three times. The purified polymer was dissolved in 80 g of cyclohexanone, and the remaining methanol and distilled water were removed under reduced pressure to obtain the polymer represented by the following chemical formula 1-7 (Mw: 3,000 g / mol).

[0116] [ka]

[0117] (Comparative Synthesis Example 2) 1 mol of 9,9-bis(3,4-dihydroxyphenyl)fluorene, 1 mol of 1,4-bis(methoxymethyl)benzene, 123 g of propylene glycol monomethyl ether acetate (PGMEA), and 0.5 g of diethyl sulfate were placed in a flask and stirred at 100°C to carry out a polymerization reaction.

[0118] After the polymerization reaction was completed, the intermediate product was gradually cooled to room temperature and added to 40 g of distilled water and 400 g of methanol, followed by vigorous stirring and settling. The supernatant was removed, and the precipitate was dissolved in 80 g of cyclohexanone. 320 g of methanol was then added, followed by vigorous stirring and settling (first step). The resulting supernatant was again removed, and the precipitate was dissolved in 80 g of cyclohexanone (second step). The first and second steps constituted one purification step, and this purification step was carried out a total of three times. The purified polymer was dissolved in 80 g of cyclohexanone, and the remaining methanol and distilled water in the solution were removed under reduced pressure to obtain the polymer represented by the following chemical formula 1-8 (Mw: 3,400 g / mol).

[0119] [ka]

[0120] (Preparation of hard mask composition) (Examples 1 to 3 and Comparative Examples 1 and 2) 3 g of each of the polymers obtained in Polymerization Examples 1 to 3 was dissolved in 17 g of cyclohexanone, and the solution was filtered through a 0.1 μm Teflon filter to prepare a hard mask composition.

[0121] <Evaluation 1: Gap-fill and planarization characteristics evaluation> FIG. 1 is a reference diagram illustrating the step height of a hard mask layer to explain the method for evaluating planarization characteristics. The hard mask compositions according to Examples 1 to 3 and Comparative Examples 1 and 2 were each applied to a silicon patterned wafer with a solvent-to-solute mass ratio of 3:97. After a baking process, a hard mask layer with a thickness of 1,100 Å was formed. The gap-fill characteristics were evaluated by observing the cross section of the pattern using a scanning electron microscope (SEM) and determining whether voids were present. The planarization characteristics were calculated by measuring the average thickness (h1) of the thin film measured at three random locations on the substrate where no pattern was formed and the average thickness (h2) of the thin film measured at three random locations on the substrate where a pattern was formed using a thin film thickness measuring device manufactured by K-MAC, and then calculating the step height (|h1 - h2|). The smaller the step height (|h1 - h2|), the better the planarization characteristics. The results are shown in Table 1 below.

[0122] [Table 1]

[0123] Referring to Table 1 above, it can be seen that the hard mask layers formed from the hard mask compositions of Examples 1 to 3 have better planarization and gap-fill properties than the hard mask layers formed from the hard mask compositions of Comparative Examples 1 and 2.

[0124] <Evaluation 2: Solubility> The solubility was confirmed by weighing and adding each of the polymers produced in Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 and 2 to 20 g of ethyl lactate (hereinafter also referred to as "EL"), propylene glycol monomethyl ether acetate (hereinafter also referred to as "PGMEA"), and propylene glycol monomethyl ether (hereinafter also referred to as "PGME"). The solubility was evaluated by measuring the amount dissolved in the same 20 g of solvent and converting it into a percentage as follows:

[0125]

number

[0126] [Table 2]

[0127] Referring to Table 2 above, it can be seen that the polymers of Synthesis Examples 1 to 3 (Examples 1 to 3) have better solubility in EL, PGMEA, and PGME than the polymers of Comparative Synthesis Examples 1 and 2 (Comparative Examples 1 and 2).

[0128] 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 present invention defined in the claims also fall within the scope of the present invention.

Claims

1. A hard mask composition comprising a polymer represented by the following Chemical Formula 1 and a solvent: 【Chemical 1】 In the above Chemical Formula 1, Ar １ ~Ar ６ are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 20 carbon atoms, X １ ~X ６ are each independently a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 20 carbon atoms, L １ and L ２ are each independently a divalent organic group, n is an integer from 1 to 100.

2. Ar in Formula 1 １ ~Ar ６ The hard mask composition according to claim 1 , wherein each independently represents a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 1 below: 【Chemistry 2】

3. X in the above Chemical Formula 1 １ ~X ６ The hard mask composition according to claim 1 , wherein each independently represents a group containing at least one selected from the group consisting of substituted or unsubstituted moieties represented by Group 2 below: 【Chemistry 3】

4. L in Formula 1 １ and L ２ are each independently at least one selected from the group consisting of groups represented by the following Chemical Formulas 2 to 5: 【Chemistry 4】 In Chemical Formula 2 to Chemical Formula 5, M １ ~M ４ are each independently a group containing at least one moiety selected from the group consisting of substituted or unsubstituted moieties represented by Group 3 below, p1 to p3 and q1 to q3 each independently represent an integer from 0 to 4; p4 is one of the integers from 1 to 5; * is the connection point: 【Chemistry 5】 In Group 3, L ａ ~L ｃ each independently represents a single bond, a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms, or a combination thereof; Z ａ and Z ｂ are each independently —O—, —S—, or —SO ２ -, -C(=O)-, or -NR ａ - (where R ａ is a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms; s1 and s2 each independently represent 0 or 1; t is one of the integers from 0 to 4.

5. L in Formula 1 １ and L ２ are each independently at least one selected from the group consisting of groups represented by the following Chemical Formulas 7 to 13: 【Chemistry 6】 In Chemical Formula 7 to Chemical Formula 13, * indicates a connection point.

6. 2. The hard mask composition according to claim 1, wherein the polymer is at least one selected from the group consisting of polymers represented by the following Chemical Formulas 1-1 to 1-3: 【Chemistry 7】 In the above Chemical Formulas 1-1 to 1-3, R １ ~R ６ are each independently a deuterium atom, a hydroxy group, a substituted or unsubstituted alkoxy group having 1 to 5 carbon atoms, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, or a combination thereof; y1 to y6 are each independently an integer from 1 to 4; Each n is independently an integer of 1 to 100.

7. 2. The hard mask composition of claim 1, wherein the weight average molecular weight of the polymer is 1,000 g / mol to 10,000 g / mol.

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

9. 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, N-methyl-2-pyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

10. A hard mask layer comprising a cured product of the hard mask composition according to any one of claims 1 to 9.

11. forming a layer of material on a substrate; applying a hard mask composition according to any one of claims 1 to 9 onto 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 a portion of the material layer; etching the exposed portions of the layer of material; A pattern forming method comprising:

12. 12. The pattern formation method of claim 11, wherein the forming of the hard mask layer comprises a heat treatment at 100 to 1,000 degrees Celsius.

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