Hard mask composition, hard mask layer and method of patterning

Abstract

This invention provides a hard mask composition, a hard mask layer manufactured from the hard mask composition, and a method for forming a pattern from the hard mask composition. The hard mask composition comprises: a polymer containing structural units represented by Chemical Formula 1 and structural units represented by Chemical Formula 2; and a solvent, wherein Chemical Formula 1 and Chemical Formula 2 are defined as described in the specification. [Chemical Formula 1] [Chemical Formula 2]

Description

[0001] Cross-reference of related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2021-0111064, filed on August 23, 2021, with the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention discloses a hard mask composition, a hard mask layer comprising a cured product of the hard mask composition, and a method for forming a pattern using the hard mask composition. Background Technology

[0004] Recently, the semiconductor industry has developed ultra-fine technology with patterns ranging from a few nanometers to tens of nanometers in size. This ultra-fine technology mainly requires efficient photolithography techniques.

[0005] A typical photolithography technique includes: providing a material layer on a semiconductor substrate; coating a photoresist layer on the material layer; exposing and developing the photoresist layer to provide a photoresist pattern; and using the photoresist pattern as a mask to etch the material layer.

[0006] Currently, given the small size of the patterns to be formed, it is difficult to provide fine patterns with excellent contours using only the typical photolithography techniques described above. Therefore, an auxiliary layer called a hard mask layer can be formed between the material layer and the photoresist layer to provide fine patterns. Summary of the Invention

[0007] One embodiment provides a hard mask composition that can be effectively coated onto a hard mask layer.

[0008] Another embodiment provides a hard mask layer comprising a cured product of a hard mask composition.

[0009] Another embodiment provides a method for forming patterns using a hard mask composition.

[0010] The hard mask composition according to the embodiments comprises a polymer and a solvent, the polymer comprising structural units represented by chemical formula 1 and structural units represented by chemical formula 2.

[0011] [Chemical Formula 1]

[0012]

[0013] In chemical formula 1,

[0014] A is a linking group containing one or more benzene rings, and when it contains two or more benzene rings, the two or more benzene rings form a fused ring, or the two or more benzene rings are linked by a single bond, -O-, -S-, or -NR. 1 -(where R)1 It can be hydrogen, C1 to C10 alkyl or C6 to C30 aryl, -C(=O)-, or -(CH2). m -(CR 2 R 3 ) n -(CH2) o -(where R) 2 and R 3 Each of the following is independently hydrogen, C1 to C10 alkyl, C6 to C20 aryl, or C3 to C10 cycloalkyl, m, n, and o are each independently an integer from 0 to 10, and m+n+o is 1 or greater) or combinations thereof connected to each other, and

[0015] B is a C6 to C30 aromatic ring substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups.

[0016] X 1 To X 4 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0017] y 1 to y 4 Each is an independent integer from 0 to 4, and

[0018] * indicates a connection point;

[0019] [Chemical Formula 2]

[0020]

[0021] In chemical formula 2,

[0022] L 1 and L 2 Each is independently a single bond, a substituted or unsubstituted divalent C1 to C15 saturated aliphatic hydrocarbon group, or a substituted or unsubstituted divalent C2 to C15 unsaturated aliphatic hydrocarbon group.

[0023] M is -O-, -S-, --SO2-, or -C(=O)-.

[0024] Z 1 and Z 2Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0025] k, l, and q are each independent integers from 0 to 4.

[0026] p is 0 or 1, and

[0027] * indicates a connection point.

[0028] In chemical formula 1, A can be any one selected from group 1.

[0029] [Group 1]

[0030]

[0031] In group 1,

[0032] R 1 It is hydrogen, C1 to C10 alkyl or C6 to C30 aryl, and

[0033] * indicates a connection point.

[0034] In chemical formula 1, B can be any one of the group 2 substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups.

[0035] [Group 2]

[0036]

[0037] In chemical formula 2, L 1 and L 2 Each can be an independent single bond or a substituted or unsubstituted C1 to C10 alkylene group, and M can be -O-, Z. 1 and Z 2 Each can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy or substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, k and l can each be independently an integer from 0 to 2, and p and q can each be 0 or 1.

[0038] In chemical formula 1, A can be any one selected from group 1-1.

[0039] [Group 1-1]

[0040]

[0041] In chemical formula 1, B can be any one of those selected from group 2-1.

[0042] [Group 2-1]

[0043]

[0044] In group 2-1,

[0045] R 4 It can be hydrogen, C1 to C10 alkyl, C2 to C10 alkenyl, or C2 to C10 alkynyl. Formula 1 can be any one of Formula 1-1 to Formula 1-11.

[0046] [Chemical Formula 1-1]

[0047]

[0048] [Chemical Formula 1-2]

[0049]

[0050] [Chemical Formulas 1-3]

[0051]

[0052] [Chemical Formulas 1-4]

[0053]

[0054] [Chemical Formulas 1-5]

[0055]

[0056] [Chemical Formulas 1-6]

[0057]

[0058] [Chemical Formulas 1-7]

[0059]

[0060] [Chemical Formulas 1-8]

[0061]

[0062] [Chemical Formulas 1-9]

[0063]

[0064] [Chemical Formulas 1-10]

[0065]

[0066] [Chemical Formula 1-11]

[0067]

[0068] In chemical formulas 1-1 to 1-11,

[0069] R' and R" are each independently hydrogen, C1 to C10 alkyl, C2 to C10 alkenyl, or C2 to C10 alkynyl.

[0070] X 1 To X 4 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0071] y 1 to y 4 Each is an independent integer from 0 to 4, and

[0072] * indicates a connection point.

[0073] Chemical formula 2 can be represented by chemical formula 2-1 or chemical formula 2-2.

[0074] [Chemical Formula 2-1]

[0075]

[0076] [Chemical Formula 2-2]

[0077]

[0078] The polymer can have a weight average molecular weight of about 1,000 g / mol to about 200,000 g / mol.

[0079] The polymer may be contained in an amount from about 0.1% to about 30% by weight, based on the total weight of the hard mask composition.

[0080] The solvent may be propylene glycol, propylene glycol diacetate, methoxypropylene glycol, 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, acetylacetone, or ethyl 3-ethoxypropionate.

[0081] According to another embodiment, a hard mask layer comprising a cured product of the aforementioned hard mask composition is provided.

[0082] According to another embodiment, a method of forming a pattern includes: providing a material layer on a substrate; coating a hard mask composition onto the material layer to form a hard mask layer; heat-treating the hard mask composition to form the 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.

[0083] The formation of the hard mask layer may involve heat treatment at approximately 100°C to approximately 1,000°C.

[0084] The hard mask composition according to the embodiments has excellent solubility in solvents and can therefore be effectively coated onto hard mask layers.

[0085] The hard mask layer formed from the hard mask composition according to the embodiments can ensure excellent gap filling features, planarization features and etch resistance. Attached Figure Description

[0086] Figure 1 The reference diagram is used to schematically illustrate the cross-section of the hard mask layer in order to explain the methods used to evaluate gap-filling and planarization features. Detailed Implementation

[0087] Examples and embodiments of the present invention will be described in detail below and can be readily practiced by those skilled in the art. However, this disclosure may be implemented in many different forms and should not be construed as limited to the examples and embodiments set forth herein.

[0088] As used herein, unless otherwise defined, 'substituted' can mean a compound in which a hydrogen atom is replaced by a substituent selected from: halogen (F, Br, Cl, or I), hydroxyl, alkoxy, nitro, cyano, amino, azide, formamidinyl, hydrazine, hydrazine, carbonyl, carbamoyl, thiol, ester, carboxyl or a salt thereof, sulfonic acid or a salt thereof, phosphate or a salt thereof, vinyl, C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C6 to C30 aryl, C7 to C30 arylalkyl, C1 to C30 alkoxy, C1 to C20 heteroalkyl, C3 to C20 heteroarylalkyl, C3 to C30 cycloalkyl, C3 to C15 cycloalkenyl, C6 to C15 cycloalkynyl, C3 to C30 heterocycloalkyl, or combinations thereof.

[0089] Additionally, two adjacent substituents of substituted halogen atoms (F, Br, Cl, or I), hydroxyl groups, nitro groups, cyano groups, amino groups, azide groups, formamidinyl groups, hydrazine groups, hydrazine groups, carbonyl groups, carboxyl groups or their salts, sulfonic acid groups or their salts, phosphate groups or their salts, C7 to C30 arylalkyl groups, C1 to C30 alkoxy groups, C1 to C20 heteroalkyl groups, C3 to C20 heteroarylalkyl groups, C3 to C30 cycloalkyl groups, C3 to C15 cycloalkenyl groups, C6 to C15 cycloalkynyl groups, and C2 to C30 heterocyclic groups can fused to form a ring. For example, a substituted C6 to C30 aryl group can fused with another adjacent substituted C6 to C30 aryl group to form a substituted or unsubstituted fluorene ring.

[0090] As used herein, unless otherwise defined, “hybrid” can refer to one containing one to three heteroatoms selected from N, O, S, Se, and P.

[0091] As used herein, unless otherwise defined, “saturated aliphatic hydrocarbon group” includes functional groups in which all bonds between carbons are single bonds, such as alkyl or alkylene groups.

[0092] As used herein, unless otherwise defined, "unsaturated aliphatic hydrocarbon group" refers to a functional group in which the intercarbon bonds contain one or more unsaturated bonds, and may contain, for example, double or triple bonds, such as alkenyl, ynyl, alkenyl or ynylyl groups.

[0093] As used herein, unless otherwise defined, "aromatic hydrocarbon group" means a group having one or more aromatic hydrocarbon moieties linked by single bonds and fused directly or indirectly to a non-aromatic fused ring. More specifically, substituted or unsubstituted aromatic hydrocarbon groups may be substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthraceneyl, substituted or unsubstituted phenanthryl, substituted or unsubstituted fused tetraphenyl, substituted or unsubstituted pyrene, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted tetraphenyl, substituted or unsubstituted trefyl, substituted or unsubstituted triphenylene, substituted or unsubstituted peryl, substituted or unsubstituted indene, combinations thereof, or combinations of the foregoing fused rings, but are not limited thereto.

[0094] As used herein, the term "aryl" refers to a group having one or more hydrocarbon aromatic moieties, and more broadly to a form in which the hydrocarbon aromatic moieties are linked by single bonds and are directly or indirectly fused with a non-aromatic fused ring. Aryl groups may contain monocyclic, polycyclic, or fused polycyclic (i.e., rings sharing adjacent carbon atom pairs) functional groups.

[0095] As used herein, unless otherwise specified, the term “combination” refers to a mixture or copolymerization.

[0096] Furthermore, as used herein, a polymer may include both oligomers and polymers.

[0097] Unless otherwise specified in this specification, the weight-average molecular weight is determined by dissolving the powder sample in tetrahydrofuran (THF) and then using Agilent Technologies' 1200 series gel permeation chromatography (GPC) with a Shodex Company LF-804 column and Showa Company polystyrene as the standard sample.

[0098] There is a constant trend in the semiconductor industry to reduce chip size, and to meet this demand, the linewidth of the resist must be patterned to tens of nanometers for photolithography. Therefore, the height of the resist can be limited to the linewidth supporting the resist pattern, but the resist may not have sufficient resistance during the etching process. To compensate for this, an auxiliary layer called a hard mask layer is used between the material layer and the photoresist layer used for etching. This hard mask layer acts as an interlayer for transferring the fine pattern of the photoresist layer through selective etching, and therefore needs to have sufficient etch resistance to withstand the etching process of pattern transfer.

[0099] On the other hand, due to the low economic efficiency of conventional hard mask layers formed in chemical or physical deposition methods due to large-scale equipment and high process costs, spin coating technology for forming hard mask layers has recently been developed. Spin coating technology is a process that is easier to perform than conventional methods, and the hard mask layers formed by it can exhibit excellent gap-filling and planarization characteristics, but there is a tendency for a slight degradation in the aforementioned etch resistance required for hard mask layers.

[0100] Recently, research has been actively conducted to maximize the carbon content of hard mask compositions in order to improve the etch resistance of hard mask layers. However, maximizing the carbon content of hard mask compositions leads to a deterioration in the solubility of the composition in solvents, making spin coating difficult to apply. Therefore, hard mask compositions need to be improved in terms of etch resistance without reducing solvent solubility.

[0101] The inventors have addressed this problem and prepared a hard mask composition for forming a hard mask exhibiting excellent gap-filling and planarization characteristics without compromising etch resistance. Efforts have also been made to ensure appropriate solubility of the hard mask composition in solvents. As a result, the carbon content in the hard mask composition is increased by using a polymer containing aromatic hydrocarbon rings to improve the etch resistance of the hard mask layer formed therefrom, wherein the polymer contains quaternary carbon to improve solubility in solvents. Furthermore, since the polymer contained in the hard mask composition also contains flow linking groups to improve the flowability of the composition during the coating process, the hard mask layer formed therefrom exhibits excellent gap-filling and planarization characteristics, thus enabling the completion of this invention.

[0102] Specifically, the hard mask composition according to one embodiment comprises a polymer containing structural units represented by chemical formula 1 and structural units represented by chemical formula 2, and a solvent.

[0103] [Chemical Formula 1]

[0104]

[0105] In chemical formula 1,

[0106] A is a linking group containing one or more benzene rings, and when it contains two or more benzene rings, the two or more benzene rings form a fused ring, or the two or more benzene rings are linked by a single bond, -O-, -S-, or -NR. 1 -(where R) 1 It can be hydrogen, C1 to C10 alkyl or C6 to C30 aryl, -C(=O)-, or -(CH2). m -(CR 2 R 3 ) n -(CH2) o -(where R) 2 and R 3 Each of the following is independently hydrogen, C1 to C10 alkyl, C6 to C20 aryl, or C3 to C10 cycloalkyl, m, n, and o are each independently an integer from 0 to 10, and m+n+o is 1 or greater) or combinations thereof connected to each other, and

[0107] B is a C6 to C30 aromatic hydrocarbon ring substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups.

[0108] X 1 To X 4Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0109] y 1 to y 4 Each is an independent integer from 0 to 4, and

[0110] * indicates a connection point:

[0111] [Chemical Formula 2]

[0112]

[0113] In chemical formula 2,

[0114] L 1 and L 2 Each is independently a single bond, a substituted or unsubstituted divalent C1 to C15 saturated aliphatic hydrocarbon group, or a substituted or unsubstituted divalent C2 to C15 unsaturated aliphatic hydrocarbon group.

[0115] M is -O-, -S-, -SO2-, or -C(=O)-.

[0116] Z 1 and Z 2 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0117] k, l, and q are each independent integers from 0 to 4.

[0118] p is 0 or 1, and

[0119] * indicates a connection point.

[0120] As described above, the polymer in the composition according to one embodiment contains aromatic hydrocarbon rings in both the structural unit represented by Formula 1 and the structural unit represented by Formula 2, thereby maximizing the carbon content in the composition. Furthermore, the flexibility of the polymer is increased by including the structural unit represented by Formula 2. The flexible structure not only increases the free volume of the polymer to improve the solubility of the composition containing it, but also increases reflow during the baking process by lowering the glass transition temperature (Tg), thereby potentially improving the gap-filling and planarization characteristics of the hard mask layer formed from this composition.

[0121] Furthermore, each structural unit polymer represented by Formula 1 contains two fluorenes to increase the carbon content in the polymer, and simultaneously includes quaternary carbons in Formula 1, resulting in a hard mask layer formed from the hard mask composition containing the polymer exhibiting high etch resistance and increased solubility in solvents. Additionally, the aromatic hydrocarbon rings A and B of Formula 1 cause interactions with other aromatic hydrocarbon rings in the polymer, such as pi-pi stacking, and the planarization characteristics of the hard mask layer formed from the composition containing them are enhanced.

[0122] The structural unit represented by Formula 1 can be obtained by the following: a Grinner reaction between fluorenone and an organometallic reagent containing a ring corresponding to A of Formula 1, and further by reacting the resulting product with an aromatic hydrocarbon compound corresponding to B of Formula 1, as can be seen from the synthetic examples described later, but the preparation method is not limited thereto.

[0123] In one embodiment, A in chemical formula 1 can be any one selected from group 1, and in group 1, R 1 It is hydrogen, C1 to C10 alkyl or C6 to C30 aryl, and * is a connecting point.

[0124] [Group 1]

[0125]

[0126] In another embodiment, A in chemical formula 1 may be any one selected from group 1-1, but is not limited thereto.

[0127] [Group 1-1]

[0128]

[0129] In one embodiment, B in Formula 1 may be any one selected from Group 2, which is substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups.

[0130] [Group 2]

[0131]

[0132] By substituting B with one or more hydroxyl groups or C1 to C10 alkoxy groups, flexibility can be imparted to polymers containing B.

[0133] In another embodiment, B in chemical formula 1 may be any one selected from group 2-1, but is not limited thereto.

[0134] [Group 2-1]

[0135]

[0136] In group 2-1, R 4 It can be hydrogen, C1 to C10 alkyl, C2 to C10 alkenyl or C2 to C10 alkynyl.

[0137] For example, chemical formula 1 can be represented by any one of chemical formulas 1-1 to 1-11.

[0138] [Chemical Formula 1-1]

[0139]

[0140] [Chemical Formula 1-2]

[0141]

[0142] [Chemical Formulas 1-3]

[0143]

[0144] [Chemical Formulas 1-4]

[0145]

[0146] [Chemical Formulas 1-5]

[0147]

[0148] [Chemical Formulas 1-6]

[0149]

[0150] [Chemical Formulas 1-7]

[0151]

[0152] [Chemical Formulas 1-8]

[0153]

[0154] [Chemical Formulas 1-9]

[0155]

[0156] [Chemical Formulas 1-10]

[0157]

[0158] [Chemical Formula 1-11]

[0159]

[0160] In chemical formulas 1-1 to 1-11,

[0161] R' and R" are each independently hydrogen, C1 to C10 alkyl, C2 to C10 alkenyl, or C2 to C10 alkynyl. R' and R" may be the same as or different from each other.

[0162] X 1 To X 4 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group.

[0163] y 1 to y 4 Each is an independent integer from 0 to 4, and

[0164] * indicates a connection point.

[0165] For example, when R' or R" is a substituted or unsubstituted C1 to C10 alkyl group, it can be methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl or octyl, such as methyl, ethyl, propyl, butyl, pentyl or hexyl, but is not limited thereto.

[0166] For example, when R' or R" is a substituted or unsubstituted C2 to C10 alkenyl group, it may have a structure containing one or more double bonds, such as vinyl, propenyl, butenyl, pentenyl, or hexenyl, but is not limited thereto.

[0167] For example, when R' or R" is a substituted or unsubstituted C2 to C20 ynyl group, it may have a structure containing one or more triple bonds, such as ethynyl, propynyl, propynyl, butynyl, pentynyl or hexynyl, but not limited thereto.

[0168] In one embodiment, L of chemical formula 2 1 and L 2 Each can be an independent single bond or a substituted or unsubstituted C1 to C10 alkylene group, M can be -O-, and Z can be... 1 and Z2 Each can be independently a deuterium, hydroxyl, halogen atom, substituted or unsubstituted C1 to C30 alkoxy group or substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, p and q can each be 0 or 1, and k and l can each be independently an integer from 0 to 2.

[0169] In the embodiments, chemical formula 2 may be represented by chemical formula 2-1 or chemical formula 2-2, but is not limited thereto:

[0170] [Chemical Formula 2-1]

[0171]

[0172] [Chemical Formula 2-2]

[0173]

[0174] The polymer may have a weight-average molecular weight from about 1,000 g / mol to about 200,000 g / mol. For example, the weight-average molecular weight of the polymer may be from about 1,000 g / mol to about 150,000 g / mol, for example from about 1,000 g / mol to about 100,000 g / mol, for example from about 1,200 g / mol to about 50,000 g / mol, or for example from about 1,200 g / mol to about 10,000 g / mol, but is not limited thereto. By having a weight-average molecular weight within the above range, the carbon content and solubility in the solvent of the hard mask composition containing the polymer can be adjusted and optimized.

[0175] The polymer may be included in an amount from about 0.1% by weight to about 30% by weight, based on the total weight of the hard mask composition. For example, the polymer may be included in an amount from about 0.2% by weight to about 30% by weight, such as about 0.5% by weight to about 30% by weight, such as about 1% by weight to about 30% by weight, such as about 1.5% by weight to about 25% by weight, such as about 2% by weight to about 20% by weight, but is not limited thereto. By including the compound within the above range, the thickness, surface roughness, and planarization of the hard mask can be easily adjusted.

[0176] The hard mask composition according to one embodiment may contain a solvent, and in one embodiment, the solvent may be at least one selected from the following: propylene glycol, propylene glycol diacetate, methoxypropylene glycol, 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, acetylacetone, ethyl 3-ethoxypropionate, etc., but is not limited thereto. The solvent is not specifically limited, provided that it has sufficient solubility and / or dispersibility for the polymer.

[0177] The hard mask composition may further include additives such as surfactants, crosslinking agents, hot acid generators, and plasticizers.

[0178] Surfactants may include, but are not limited to, fluoroalkyl compounds, alkylbenzene sulfonates, alkylpyridinium salts, polyethylene glycol, quaternary ammonium salts, etc.

[0179] The crosslinking agent can be, for example, a melamine-based, substituted urea-based, or polymeric crosslinking agent. Ideally, it can be a crosslinking agent having at least two crosslinking substituents, such as compounds of methoxymethylated glycourea, butoxymethylated glycourea, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or butoxymethylated thiourea.

[0180] In addition, crosslinking agents with high heat resistance can be used as crosslinking agents. Crosslinking agents with high heat resistance may contain compounds having crosslinking substituents with aromatic rings (e.g., benzene rings or naphthalene rings) in their molecules.

[0181] The hot acid generating agent may be, for example, an acid compound, such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid pyridinium, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, hydroxybenzoic acid, naphthoic acid and / or 2,4,4,6-tetrabromocyclohexadienone, benzoin toluenesulfonate, 2-nitrobenzyl toluenesulfonate and other organic alkyl sulfonates, but is not limited thereto.

[0182] According to another embodiment, a hard mask layer comprising a cured product of the aforementioned hard mask composition is provided.

[0183] The following describes a method for forming patterns using the aforementioned hard mask composition.

[0184] A method for forming a pattern according to one embodiment includes: providing a material layer on a substrate; coating the material layer with a hard mask composition comprising the aforementioned polymer and solvent; 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.

[0185] The substrate can be, for example, a silicon wafer, a glass substrate, or a polymer substrate.

[0186] The material layer is the material that will ultimately be patterned, such as a metal layer, like an aluminum or copper layer; a semiconductor layer, like a silicon layer; or an insulating layer, like a silicon oxide or silicon nitride layer. The material layer can be formed by methods such as chemical vapor deposition (CVD).

[0187] The hard mask composition is the same as described above and can be applied in solution form by spin coating. The thickness of the hard mask composition is not specifically limited herein, but can be, for example, from about 50 angstroms to about 200,000 angstroms.

[0188] The heat treatment of the hard mask composition can be carried out, for example, at about 100°C to about 1,000°C for about 10 seconds to about 1 hour.

[0189] For example, the heat treatment of a hard mask composition may include multiple heat treatment processes, such as a first heat treatment process and a second heat treatment process.

[0190] In an embodiment, the heat treatment of the hard mask composition may include, for example, a heat treatment process performed at about 10 seconds to about 1 hour at about 100°C to about 1000°C, and for example, the heat treatment may be performed in an atmosphere of air or nitrogen or an atmosphere with an oxygen concentration of 1% by weight or less.

[0191] In embodiments, the heat treatment of the hard mask composition may include a first heat treatment process for about 10 seconds to about 1 hour at, for example, about 100°C to about 1,000°C, for example, about 100°C to about 800°C, for example, about 100°C to about 500°C, or for example, about 100°C to about 400°C, and a second heat treatment process for about 10 seconds to about 1 hour continuously at, for example, about 100°C to about 1,000°C, for example, about 300°C to 1,000°C, for example, about 500°C to 1,000°C, or for example, about 500°C to 800°C. For example, the first and second heat treatment processes may be performed in an atmosphere of air or nitrogen or in an atmosphere with an oxygen concentration of 1% by weight or less.

[0192] By performing at least one step of heat-treating the hard mask composition at a high temperature of 200°C or higher, high etch resistance can be exhibited, enabling it to withstand etch gases and chemical liquids exposed in subsequent processes including etching processes.

[0193] In the embodiments, the formation of the hard mask layer may include a UV / Vis curing process and / or a near-IR curing process.

[0194] In an embodiment, the formation of the hard mask layer may include at least one of a first heat treatment process, a second heat treatment process, a UV / Vis curing process, and a near-IR curing process, or may include two or more consecutive processes.

[0195] In an embodiment, the method may further include forming a silicon-containing thin layer on a hard mask layer. The silicon-containing thin layer may be formed, for example, from materials such as SiCN, SiOC, SiON, SiOCN, SiC, SiO, and / or SiN.

[0196] In an embodiment, the method may further include forming a bottom anti-reflective coating (BARC) on a silicon-containing thin layer or a hard mask layer before forming the photoresist layer.

[0197] In this embodiment, the photoresist layer can be exposed using, for example, ArF, KrF, or EUV. Following exposure, heat treatment can be performed at approximately 100°C to approximately 700°C.

[0198] In the embodiments, the etching process of the exposed portion of the material layer can be performed by a dry etching process using an etching gas, and the etching gas can be, but is not limited to, N2 / O2, CHF3, CF4, Cl2, BCl3 and mixtures thereof.

[0199] Multiple patterns can be formed to create an etched material layer, and these patterns can be metal patterns, semiconductor patterns, insulating patterns, etc., such as different patterns in a semiconductor integrated circuit device.

[0200] The present disclosure is described in more detail below with reference to examples. However, these examples are exemplary and the present disclosure is not limited thereto.

[0201] Example

[0202] Synthesis Examples 1 to 3: Synthesis of Monomers

[0203] Synthesis Example 1

[0204] 1,4-Bis(9-hydroxy-9-fluorenyl)benzene is prepared by mixing 2 molar equivalents of fluorenone and 1 molar equivalent of p-dibromobenzene as shown in reaction procedure 1 below, and adding 2 molar equivalents of phenol and reacting with it to obtain monomer 1 represented by chemical formula X1.

[0205] [Reaction Flow 1]

[0206]

[0207] [Chemical Formula X1]

[0208]

[0209] Synthesis Example 2

[0210] Monomer 2, represented by chemical formula X2, is prepared by mixing 2 molar equivalents of fluorenone and 1 molar equivalent of 4,4'-dibromophenyl to prepare 9-[4-[4-(9-hydroxy-1,2-dihydrofluoren-9-yl)phenyl]phenyl]fluoren-9-ol, and then 2 molar equivalents of phenol are added to it and reacted to obtain the product.

[0211] [Chemical formula X2]

[0212]

[0213] Synthesis Example 3

[0214] Monomer 3, represented by chemical formula X3, is obtained by mixing 2 molar equivalents of fluorenone and 1 molar equivalent of bis-(4-bromophenyl) ether, followed by adding 2 molar equivalents of 2-naphthol and reacting the mixture.

[0215] [Chemical Formula X3]

[0216]

[0217] Synthesis Examples 4 to 8: Synthesizing Polymers

[0218] Synthesis Example 4

[0219] A solution was prepared using 1 mole of monomer (represented by Formula X1 according to Synthesis Example 1), 1 mole of 1,4-bis(methoxymethyl)benzene, and 250 g of propylene glycol monomethyl ether acetate (PGMEA) as solvent. 10 mmol of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing structural units represented by Formula 1-1a. (Mw: 6,540 g / mol)

[0220] [Chemical Formula 1-1a]

[0221]

[0222] Synthesis Example 5

[0223] Polymers comprising structural units represented by chemical formulas 1-2a were obtained in the same manner as in Synthesis Example 4, except that the monomer represented by chemical formula X2 according to Synthesis Example 2 was used instead of the monomer according to Synthesis Example 1. (Mw: 4,318 g / mol)

[0224] [Chemical Formula 1-2a]

[0225]

[0226] Synthesis Example 6

[0227] According to Synthesis Example 2, 1 mole of monomer (represented by Formula X2), 1 mole of 4,4'-dimethoxymethyl diphenyl ether, and 250 g of propylene glycol monomethyl ether acetate (PGMEA) were used as solvents to prepare a solution. 5 mmol of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing structural units represented by Formulas 1-2b. (Mw: 3,950 g / mol)

[0228] [Chemical Formula 1-2b]

[0229]

[0230] Synthesis Example 7

[0231] Polymers comprising structural units represented by chemical formulas 1-7a were obtained in the same manner as in Synthesis Example 4, except that the monomer represented by chemical formula X3 according to Synthesis Example 3 was used instead of the monomer according to Synthesis Example 1. (Mw: 3,381 g / mol)

[0232] [Chemical Formula 1-7a]

[0233]

[0234] Synthesis Example 8

[0235] A solution was prepared using 1 mole of monomer (represented by chemical formula X3 according to Synthesis Example 3), 1 mole of 4,4'-dimethoxymethyl diphenyl ether, and 50 g of propylene glycol monomethyl ether acetate as solvents. 5 mmol of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing structural units represented by chemical formulas 1-7b. (Mw: 3,127 g / mol)

[0236] [Chemical Formula 1-7b]

[0237]

[0238] Comparative Synthesis Example 1

[0239] A solution was prepared using 1 mole of monomer (represented by chemical formula X1 according to Synthesis Example 1), 1 mole of paraformaldehyde, and 250 g of propylene glycol monomethyl ether acetate (PGMEA) as a solvent. 7 mmol of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing the structural unit represented by chemical formula a. (Mw: 8,900 g / mol)

[0240] [Chemical formula a]

[0241]

[0242] Comparative Synthesis Example 2

[0243] A solution was prepared using 1 mole of monomer (represented by chemical formula X2 according to Synthesis Example 2), 1 mole of paraformaldehyde, and 250 g of propylene glycol monomethyl ether acetate (PGMEA) as a solvent. 7 mmol of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing the structural unit represented by chemical formula b. (Mw: 13,200 g / mol)

[0244] [Chemical formula b]

[0245]

[0246] Comparative Synthesis Example 3

[0247] A solution was prepared by placing 50.0 g (0.143 mol) of 9,9'-bis(4-hydroxyphenyl)fluorene, 23.7 g (0.143 mol) of 1,4-bis(methoxymethyl)benzene, and 50 g of propylene glycol monomethyl ether acetate in a flask as solvents. 1.10 g (7.13 mmol) of diethyl sulfate was added to the solution, and the mixture was then stirred at 100 °C for 24 hours. Upon completion of polymerization, the product was precipitated in methanol to remove monomers and low molecular weight substances, yielding a polymer containing structural units represented by the chemical formula C. (Mw: 33,500 g / mol)

[0248] [Chemical formula c]

[0249]

[0250] Examples and Comparative Examples: Preparation of Hard Mask Compositions

[0251] Example 1

[0252] A hard mask composition was prepared by dissolving 3.3 g of the compound according to Synthesis Example 4 in 30 g of propylene glycol monomethyl ether acetate (PGMEA) and then filtering it through a 0.1 μm TEFLON (tetrafluoroethylene) filter.

[0253] Example 2

[0254] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Synthesis Example 5 was used instead of the compound of Synthesis Example 4.

[0255] Example 3

[0256] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Synthesis Example 6 was used instead of the compound of Synthesis Example 4.

[0257] Example 4

[0258] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Synthesis Example 7 was used instead of the compound of Synthesis Example 4.

[0259] Example 5

[0260] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Synthesis Example 8 was used instead of the compound of Synthesis Example 4.

[0261] Comparison Example 1

[0262] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Comparative Example 1 was used instead of the compound of Comparative Example 4.

[0263] Comparison Example 2

[0264] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Comparative Example 2 was used instead of the compound of Comparative Example 4.

[0265] Comparison Example 3

[0266] The hard mask composition was prepared in the same manner as in Example 1, except that the compound of Comparative Example 3 was used instead of the compound of Comparative Example 4.

[0267] Evaluation 1: Evaluate gap-filling and planarization features

[0268] Figure 1 Reference figures are provided to illustrate the step difference of the hard mask layer in order to explain the method used to evaluate planarization features. Hard mask compositions according to Examples 1 to 5 and Comparative Examples 1 to 3 were coated onto silicon patterned wafers to form 1,100 angstrom-thick organic films by adjusting the solvent-to-solute mass ratio to 3 to 97 and then baking. Gap-filling features were evaluated by observing the patterned cross-section of the film using scanning electron microscopy (SEM) to determine the presence or absence of voids. Planarization features of the film were evaluated by measuring the thickness of each of the surrounding and unit regions in the SEM image (step measurement). The step difference results were calculated using h0–h4. The results are shown in Table 1.

[0269] [Table 1]

[0270]

[0271] Referring to Table 1, compared with the organic films formed by the hard mask compositions according to Comparative Examples 1 to 2, the organic films formed by the hard mask compositions according to Examples 1 to 5 exhibit excellent planarization and gap-filling characteristics.

[0272] Evaluation 2: Etching resistance

[0273] Each hard mask composition of Examples 1 to 5 and Comparative Examples 1 to 3 (15 wt%) was spin-coated onto a silicon wafer and then heat-treated on a hot plate at 400°C for 2 minutes to form a 4000 angstrom thick film. The film thickness was measured relative to the thickness using a film thickness gauge prepared by K-MAC. Subsequently, the films were dry-etched for 100 seconds and 60 seconds respectively using a CHF3 / CF4 mixed gas and an N2 / O2 mixed gas, and the thickness was then measured relative to the thickness to calculate the thickness difference of each organic film before and after the dry etching, which was used in conjunction with the etching time to calculate the bulk etch rate (BER) according to Equation 1. The results are shown in Table 2.

[0274] [Calculate Equation 1]

[0275] Etching rate (angstroms / second) = (Initial film thickness - Post-etched film thickness) / Etching time (seconds)

[0276] [Table 2]

[0277] <![CDATA[CF x Bulk etch rate (Å / s) <![CDATA[Etching rate of N2 / O2 (Å / sec)]]> Example 1 30.1 28.6 Example 2 30.4 29.8 Example 3 29.5 27.5 Example 4 28.6 27.5 Example 5 28.1 26.2 Comparison Example 1 28.4 29.4 Comparison Example 2 30.7 32.0 Comparison Example 3 29.0 30.3

[0278] Referring to Table 2, the films formed by the hard mask compositions according to Examples 1 to 5 exhibit similar or lower etch rates compared to those formed by the hard mask compositions according to Comparative Examples 1 to 3. Therefore, the hard mask compositions according to Examples 1 to 5 exhibit similar or higher etch resistance compared to the hard mask compositions according to Comparative Examples 1 to 3.

[0279] Assessment 3: Solubility Assessment

[0280] The hard mask compositions according to Examples 1 to 5 and Comparative Examples 1 to 3 were stored at low temperature (3°C or lower) for 3 months, and then examined relative to the amount of precipitate.

[0281] An excellent rating is given when the solid does not visually precipitate in a solution with visible solubility.

[0282] When a solid precipitates in a solution, give O; when no solid precipitates, give X.

[0283] [Table 3]

[0284] Precipitation or non-precipitation Example 1 No sedimentation Example 2 No sedimentation Example 3 No sedimentation Example 4 No sedimentation Example 5 No sedimentation Comparison Example 1 precipitation Comparison Example 2 precipitation Comparison Example 3 precipitation

[0285] Referring to Table 3, Examples 1 to 5 show improved solubility compared to Comparative Examples 1 to 3.

[0286] While the invention has been described in conjunction with what is now considered to be practical examples, it should be understood that the invention is not limited to the disclosed embodiments. Rather, it is intended to cover various modifications and equivalent arrangements that fall within the spirit and scope of the appended claims.

Claims

1. A hard mask composition, comprising: A polymer comprising structural units represented by chemical formula 1 and structural units represented by chemical formula 2; as well as Solvent: [Chemical Formula 1] In chemical formula 1, A is any one selected from group 1. [Group 1] In group 1, R 1 It is hydrogen, C1 to C10 alkyl or C6 to C30 aryl, and * indicates a connection point. B is a C6 to C30 aromatic hydrocarbon ring substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups. X 1 To X 4 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group. y 1 to y 4 Each is an independent integer from 0 to 4, and * indicates a connection point: [Chemical Formula 2] In chemical formula 2, L 1 and L 2 Each is independently a single bond, a substituted or unsubstituted divalent C1 to C15 saturated aliphatic hydrocarbon group, or a substituted or unsubstituted divalent C2 to C15 unsaturated aliphatic hydrocarbon group. M is -O-, -S-, -SO2-, or -C(=O)-. Z 1 and Z 2 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group. k, l, and q are each independent integers from 0 to 4. p is 0 or 1, and * indicates a connection point.

2. The hard mask composition according to claim 1, wherein B in formula 1 is any one selected from group 2 substituted with one or more hydroxyl groups or C1 to C10 alkoxy groups: [Group 2] 3. The hard mask composition according to claim 1, wherein in chemical formula 2, L 1 and L 2 Each is independently a single bond or a substituted or unsubstituted C1 to C10 alkylene group. M is -O-, Z 1 and Z 2 Each is independently a deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group or substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group. k and l are each an independent integer from 0 to 2, and p and q are each 0 or 1.

4. The hard mask composition according to claim 1, wherein A in formula 1 is any one selected from group 1-1: [Group 1-1] 5. The hard mask composition according to claim 1, wherein B in formula 1 is any one selected from group 2-1: [Group 2-1] in, In group 2-1, R 4 It is hydrogen or C1 to C10 alkyl.

6. The hard mask composition according to claim 1, wherein chemical formula 1 is any one of chemical formulas 1-1 to 1-11: [Chemical Formula 1-1] [Chemical Formula 1-2] [Chemical Formulas 1-3] [Chemical Formulas 1-4] [Chemical Formulas 1-5] [Chemical Formulas 1-6] [Chemical Formulas 1-7] [Chemical Formulas 1-8] [Chemical Formulas 1-9] [Chemical Formulas 1-10] [Chemical Formula 1-11] in, In chemical formulas 1-1 to 1-11, R' and R" are each independently hydrogen or C1 to C10 alkyl, wherein R' and R" are identical to each other. X 1 To X 4 Each of these can be independently deuterium, hydroxyl, halogen, substituted or unsubstituted C1 to C30 alkoxy group, substituted or unsubstituted C1 to C30 saturated aliphatic hydrocarbon group, substituted or unsubstituted C2 to C30 unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C6 to C30 aromatic hydrocarbon group, substituted or unsubstituted C1 to C30 heteroalkyl group, or substituted or unsubstituted C2 to C30 heteroaromatic hydrocarbon group. y 1 to y 4 Each is an independent integer from 0 to 4, and * indicates a connection point.

7. The hard mask composition according to claim 1, wherein chemical formula 2 is represented by chemical formula 2-1 or chemical formula 2-2: [Chemical Formula 2-1] [Chemical Formula 2-2] 8. The hard mask composition according to claim 1, wherein the polymer has a weight-average molecular weight of 1,000 g / mol to 200,000 g / mol.

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

10. The hard mask composition according to claim 1, wherein the solvent is propylene glycol, propylene glycol diacetate, methoxypropylene glycol, 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, acetylacetone, or ethyl 3-ethoxypropionate.

11. A hard mask layer comprising a cured product of the hard mask composition as claimed in claim 1.

12. A method for forming a pattern, comprising: Provide a material layer on the substrate; The hard mask composition according to claim 1 is coated onto the material layer; The hard mask composition is heat-treated to form a hard mask layer; A photoresist layer is formed on the hard mask layer; The photoresist layer is exposed and developed to form a photoresist pattern; The hard mask layer is selectively removed using the photoresist pattern to expose a portion of the material layer; as well as Etch the exposed portion of the material layer.

13. The method of forming a pattern according to claim 12, wherein forming the hard mask layer comprises heat treatment at 100°C to 1,000°C.

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