KR102504797B1 - Hardmask composition and method of forming patterns - Google Patents

Abstract

상기 화학식 1에서, A 내지 C의 정의는 명세서에 기재한 바와 같다.It relates to a hard mask composition including a polymer including a structural unit represented by Chemical Formula 1 and a solvent, and a pattern forming method.
[Formula 1]

In Formula 1, the definitions of A to C are as described in the specification.

Description

Hard mask composition and pattern forming method {HARDMASK COMPOSITION AND METHOD OF FORMING PATTERNS}

A hard mask composition and a pattern forming method using the hard mask composition.

In recent years, the semiconductor industry has been developing from hundreds of nanometer-sized patterns to ultra-fine technologies having several to several tens of nanometer-sized patterns. Effective lithographic techniques are essential to realize these ultra-fine technologies.

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

Recently, as the size of a pattern to be formed decreases, it is difficult to form a fine pattern having a good profile only with the above-described typical lithographic techniques. Accordingly, a fine pattern may be formed by forming an auxiliary layer called a hardmask layer between the material layer to be etched and the photoresist layer.

One embodiment provides a hardmask composition that can be effectively applied to a hardmask layer.

Another embodiment provides a pattern forming method using the hard mask composition.

According to one embodiment, a hard mask composition including a polymer including a structural unit represented by Chemical Formula 1 and a solvent is provided.

[Formula 1]

In Formula 1,

A is an aromatic ring substituted with at least one hydrogen bondable group,

B is a C6 to C30 aryl group substituted with at least one nitro group,

C is hydrogen, heavy hydrogen, a hydroxyl group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

A is selected from the following group 1, and may be any one substituted with at least one hydrogen bondable group.

[Group 1]

A may be a condensed aromatic ring substituted with at least one hydrogen bondable group.

A may be any one selected from Group 2 below.

[Group 2]

In Group 2, R ¹ and R ² are hydrogen bondable groups.

The hydrogen bondable group is halogen, -OR ^a , -NR ^b R ^c or a combination thereof,

Wherein R ^a to R ^c are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.

R ^a is hydrogen, and at least one of R ^b and R ^c may be hydrogen.

B is selected from Group 3 and may be any one substituted with at least one nitro group.

[Group 3]

B is further substituted with halogen, -OR ^d , -NR ^e R ^f or a combination thereof;

R ^d to R ^f are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, or a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.

R ^d is hydrogen, and at least one of R ^e and R ^f may be hydrogen.

The structural unit represented by Chemical Formula 1 may be represented by Chemical Formula 2 or 3 below.

[Formula 2]

[Formula 3]

In Formulas 2 and 3,

C is hydrogen, heavy hydrogen, a hydroxyl group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof;

R ¹ and R ² are each independently halogen, -OR ^a , -NR ^b R ^c or a combination thereof;

R ³ is a nitro group;

each R ⁴ is independently halogen, -OR ^d , -NR ^e R ^f or a combination thereof;

Wherein R ^a to R ^f are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof;

m and n are each independently 0 or 1;

R ^a and R ^d may be hydrogen, at least one of R ^b and R ^c may be hydrogen, and at least one of R ^e and R ^f may be hydrogen.

At least one of R ¹ , R ² and R ⁴ may be a hydroxyl group.

At least one of m and n may be 0.

According to another embodiment, forming a hard mask layer by applying the above-described hard mask composition on a material layer and performing heat treatment, forming a photoresist layer on the hard mask layer, exposing and developing the photoresist layer to form a photoresist layer. Forming a resist 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. provides a way

Solubility and storage stability of the polymer and etch resistance and film density of the hard mask layer can be simultaneously secured.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments set forth herein.

Unless otherwise specified herein, 'substituted' means that a hydrogen atom in a compound is deuterium, a halogen atom (F, Br, Cl, or I), a hydroxyl group, a nitro group, a cyano group, an amino group, an azido group, an amidino group, hydrazino group, hydrazono group, carbonyl group, carbamyl group, thiol group, ester group, carboxyl group or its salt thereof, sulfonic acid group or its salt thereof, phosphoric acid group or its salt thereof, C1 to C30 alkyl group, C2 to C30 alkenyl group, C2 to C30 C30 alkynyl group, C6 to C30 aryl group, C7 to C30 arylalkyl group, C1 to C30 alkoxy group, C1 to C30 heteroalkyl group, C3 to C30 heteroarylalkyl group, C3 to C30 cycloalkyl group, C3 to C15 cycloalkenyl group, C6 to C30 It means that it is substituted with a substituent selected from a C15 cycloalkynyl group, a C2 to C30 heterocyclic group, and combinations thereof.

In addition, the substituted halogen atom (F, Br, Cl, or I), hydroxy group, nitro group, cyano group, amino group, azido group, amidino group, hydrazino group, hydrazono group, carbonyl group, carbamyl group, thiol group , Ester group, carboxyl group or a salt thereof, sulfonic acid group or a salt thereof, phosphoric acid or a salt thereof, C1 to C30 alkyl group, C2 to C30 alkenyl group, C2 to C30 alkynyl group, C6 to C30 aryl group, C7 to C30 arylalkyl group, C1 to C30 Two adjacent substituents of a C30 alkoxy group, a C1 to C30 heteroalkyl group, a C3 to C30 heteroarylalkyl group, a C3 to C30 cycloalkyl group, a C3 to C15 cycloalkenyl group, a C6 to C15 cycloalkynyl group, or a C2 to C30 heterocyclic group They can also fuse to form rings. For example, the substituted C6 to C30 aryl group may be fused with another adjacent substituted C6 to C30 aryl group to form a substituted or unsubstituted fluorene ring.

In addition, unless otherwise defined herein, 'hetero' means containing 1 to 3 heteroatoms selected from N, O, S, Se and P.

As used herein, "aryl group" refers to a group having one or more hydrocarbon aromatic moieties, and broadly refers to a form in which hydrocarbon aromatic moieties are connected by a single bond and a non-aromatic hydrocarbon aromatic moiety directly or indirectly fused. Fused rings are also included. Aryl groups include monocyclic, polycyclic or fused polycyclic (ie, rings that divide adjacent pairs of carbon atoms) functional groups.

In the present specification, "heterocyclic group" is a concept including a heteroaryl group, and in addition to this, in a ring compound such as an aryl group, a cycloalkyl group, a fused ring thereof, or a combination thereof, instead of carbon (C) It means containing at least one hetero atom selected from N, O, S, P, and Si. When the heterocyclic group is a fused ring, the entire heterocyclic group or each ring may include one or more heteroatoms.

More specifically, the substituted or unsubstituted aryl group is a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthryl group, or a substituted or unsubstituted naphthyl group. Cenyl group, substituted or unsubstituted pyrenyl group, substituted or unsubstituted biphenyl group, substituted or unsubstituted terphenyl group, substituted or unsubstituted quaterphenyl group, substituted or unsubstituted chrysenyl group, substituted or unsubstituted triphenyl group A phenylenyl group, a substituted or unsubstituted perylenyl group, a substituted or unsubstituted indenyl group, a substituted or unsubstituted fluorenyl group, a combination thereof, or a combination thereof may be fused, but is not limited thereto. .

More specifically, the substituted or unsubstituted heterocyclic group is a substituted or unsubstituted furanyl group, a substituted or unsubstituted thiophenyl group, a substituted or unsubstituted pyrrolyl group, a substituted or unsubstituted pyrazolyl group, a substituted or unsubstituted thiophenyl group, or a substituted or unsubstituted pyrazolyl group. imidazolyl group, substituted or unsubstituted triazolyl group, substituted or unsubstituted oxazolyl group, substituted or unsubstituted thiazolyl group, substituted or unsubstituted oxadiazolyl group, substituted or unsubstituted thiadiazole Dial, substituted or unsubstituted pyridinyl group, substituted or unsubstituted pyrimidinyl group, substituted or unsubstituted pyrazinyl group, substituted or unsubstituted triazinyl group, substituted or unsubstituted benzofuranyl group, substituted or unsubstituted group A substituted or unsubstituted benzothiophenyl group, a substituted or unsubstituted benzimidazolyl group, a substituted or unsubstituted indolo group, a substituted or unsubstituted quinolinyl group, a substituted or unsubstituted isoquinolinyl group, a substituted or unsubstituted quina A zolinyl group, a substituted or unsubstituted quinoxalinyl group, a substituted or unsubstituted naphthyridinyl group, a substituted or unsubstituted benzoxazinyl group, a substituted or unsubstituted benzthiazinyl group, a substituted or unsubstituted acridinyl group, A substituted or unsubstituted phenazinyl group, a substituted or unsubstituted phenothiazinyl group, a substituted or unsubstituted phenoxazinyl group, a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted dibenzothiophenyl group, or An unsubstituted carbazolyl group, a substituted or unsubstituted pyridoindolo group, a substituted or unsubstituted benzopyridooxazinyl group, a substituted or unsubstituted benzopyridothiazinyl group, a substituted or unsubstituted 9,9- A dimethyl 9,10 dihydroacridinyl group, a combination thereof, or a combination thereof may be fused, but is not limited thereto. In one example of the present invention, the heterocyclic group or heteroaryl group may be a pyrrole group, an indolo group, or a carbazolyl group.

Also, in the present specification, a polymer means including an oligomer and a polymer.

Hereinafter, a hardmask composition according to an embodiment will be described.

A hardmask composition according to one embodiment includes a polymer and a solvent.

The polymer may include a main chain including an aromatic ring and a side chain bonded to the main chain and including an aromatic ring substituted with a nitro group.

Accordingly, by including aromatic rings having a high carbon content in the main chain and side chains, it is possible to form a hard film-like polymer layer, thereby improving etching resistance, and by including aromatic rings having a nitro group in the side chains, the solvent of the polymer solubility can be increased. Accordingly, the polymer can be prepared as a solution and effectively formed into a polymer layer by a solution process such as spin-on coating, and the formed polymer layer can reduce or prevent damage by an etching gas exposed in a subsequent etching process due to its high etching resistance. can

The aromatic ring of the main chain may be substituted with a hydrogen bondable group. The hydrogen bondable group refers to a group capable of forming a hydrogen bond with another functional group, and by including an aromatic ring having a hydrogen bondable group in the main chain, the solubility of the polymer is improved. can be raised further.

For example, the polymer may include a structural unit represented by Chemical Formula 1 below.

[Formula 1]

In Formula 1,

A is an aromatic ring substituted with at least one hydrogen bondable group,

B is a C6 to C30 aryl group substituted with at least one nitro group,

C is hydrogen, Deuterium, a hydroxyl group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

The aromatic ring is a single ring; It is a fused ring in which two or more aromatic rings are fused; Two or more aromatic rings may be unfused rings connected by single bonds, C1 to C5 alkylene groups, O, C(=0) or OC(=0).

For example, A may be selected from Group 1 below, and an aromatic ring listed in Group 1 may be substituted with at least one hydrogen bondable group.

[Group 1]

In the aromatic rings listed in Group 1, the point of connection with the polymer may be any two of the carbon atoms forming the ring and is not particularly limited.

For example, A may be a polycyclic aromatic ring substituted with at least one hydrogen bondable group, a condensed aromatic ring substituted with at least one hydrogen bondable group, and/or a non-fused aromatic ring substituted with at least one hydrogen bondable group. However, it may preferably be a condensed aromatic ring substituted with at least one hydrogen bondable group. Accordingly, since the carbon content of the polymer can be further increased and a hard polymer layer can be formed, more excellent etching resistance can be imparted.

The A may be substituted with at least one hydrogen bondable group, for example, may be substituted with at least two hydrogen bondable groups, for example, may be substituted with one or two hydrogen bondable groups.

The A may be further substituted or unsubstituted with other substituents other than the hydrogen bondable group. The type and number of substituents other than the hydrogen bondable group are not limited.

For example, A may not have an electron withdrawing group (EWG) as a substituent, wherein the electron withdrawing group is, for example, a nitro group, a trifluoromethyl group, a carbonyl group, a nitrile group, or a combination thereof. can

For example, A may not have a nitro group as a substituent.

For example, A may be pyrene substituted with at least one hydrogen bondable group, and may be, for example, any one selected from Group 2 below.

[Group 2]

In the pyrenes listed in Group 2 above, the point of connection with the polymer may be any two of the carbons constituting pyrene, and is not particularly limited.

In Group 2, R ¹ and R ² are hydrogen bondable groups. Here, R ¹ and R ² may be the same as or different from each other.

At least one of the hydrogen bondable groups may form a hydrogen bond with at least one nitro group substituted on the aromatic ring of B. Accordingly, a polymer layer having excellent film density can be formed by the aforementioned polar bonds between the polymers and/or polar bonds within the polymers. In addition, adhesion of the polymer to the substrate and/or the upper film is improved, so that it can have excellent gap-fill and planarization properties.

For example, the hydrogen bondable group may be halogen, -OR ^a , -NR ^b R ^c or a combination thereof,

Wherein R ^a to R ^c are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.

For example, R ^a to R ^c are each independently hydrogen, a substituted or unsubstituted methyl group, a substituted or unsubstituted ethyl group, a substituted or unsubstituted propyl group, a substituted or unsubstituted butyl group, a substituted or unsubstituted phen A substituted or unsubstituted hexyl group, a substituted or unsubstituted ethenyl group, a substituted or unsubstituted propenyl group, a substituted or unsubstituted butenyl group, a substituted or unsubstituted pentenyl group, a substituted or unsubstituted hexenyl group , A substituted or unsubstituted ethynyl group, a substituted or unsubstituted propynyl group, a substituted or unsubstituted butynyl group, a substituted or unsubstituted pentynyl group, a substituted or unsubstituted hexynyl group, or a combination thereof.

For example, R ^a may be hydrogen, and thus the hydrogen bondable group may be a hydroxyl group.

For example, at least one of R ^b and R ^c may be hydrogen.

For example, R ^b and R ^c may each be hydrogen, and thus the hydrogen bondable group may be an amino group.

For example, R ^a is hydrogen, and at least one of R ^b and R ^c may be hydrogen.

Accordingly, the hydrogen bondable group can form a hydrogen bond with at least one nitro group substituted on the aromatic ring of B, and the polar bond between the polymers and/or the polar bond within the polymer provides a polymer layer having a higher film density. can form

For example, each of R ^a to R ^c may be hydrogen.

For example, R ^a to R ^c may be the same as or different from each other.

For example, the hydrogen bondable group may be -OR ^a , where R ^a is as described above. Accordingly, by increasing the oxygen atom content in the structural unit of the polymer, it is possible to further improve the corrosion resistance to the N ₂ /O ₂ mixed gas.

For example, the hydrogen bondable group may be -OR ^a , where R ^a may be hydrogen.

As described above, the polymer may include an aryl group (B) substituted with at least one nitro group on the side chain, and at least one hydrogen bond between the aryl group (B) substituted with at least one nitro group on the side chain and the main chain is possible. The aromatic ring (A) substituted with a group may be bonded by a tertiary or quaternary carbon. Here, tertiary carbon is defined as a central carbon in which three of the four bonds that the central carbon can make are bonded to different carbons, and quaternary carbon means that all four bonds that the central carbon can make are different from each other. It is defined as being the central carbon bonded to carbon. By including tertiary or quaternary carbon in the polymer, solubility in solvents can be increased, and since a hard polymer layer can be formed by increasing the carbon content, high etching resistance can be imparted.

For example, the aryl group is a phenyl group; It is a fused ring aryl group in which two or more aromatic rings are fused; Two or more aromatic rings may be unfused ring groups connected by single bonds, C1 to C5 alkylene groups, O, C(=O) or OC(=O).

For example, B may be a phenyl group substituted with at least one nitro group or a polycyclic aryl group substituted with at least one nitro group, and the polycyclic aryl group may be a condensed cyclic aryl group and/or a non-fused cyclic aryl group.

For example, B may be selected from Group 3 below, and the aryl group listed in Group 3 below may be substituted with at least one nitro group.

[Group 3]

In the aryl group listed in Group 3 above, the connection point with the polymer and the substitution site of the nitro group may be any one of carbon constituting the aryl group and is not particularly limited.

For example, B is a phenyl group substituted with at least one nitro group, a naphthyl group substituted with at least one nitro group, a biphenyl group substituted with at least one nitro group, a phenanthrenyl group substituted with at least one nitro group, or at least one nitro group. A substituted anthracenyl group, a fluorenyl group substituted with at least one nitro group, a pyrenyl group substituted with at least one nitro group, a chrysenyl group substituted with at least one nitro group, a picenyl group substituted with at least one nitro group, triphenylenyl group substituted with at least one nitro group, fluoranthenyl group substituted with at least one nitro group, acenaphthylenyl group substituted with at least one nitro group, acenaphthenyl group substituted with at least one nitro group, at least one A benzophenanthrenyl group substituted with a nitro group, a benzofluoranthenyl group substituted with at least one nitro group, a perylenyl group substituted with at least one nitro group, a benzopyrenyl group substituted with at least one nitro group, and at least one nitro group. It may be a naphthoanthracenyl group substituted with a group, a benzoperylenyl group substituted with at least one nitro group, a dibenzopyrenyl group substituted with at least one nitro group, or a coronenyl group substituted with at least one nitro group.

For example, B may be substituted with one or two nitro groups.

When B contains a nitro group, as described above, the polymer can have high solubility in various solvents, and thus the storage stability and coating uniformity of the polymer can be improved. In addition, since B includes a nitro group, the content of oxygen atoms in the structural unit is increased to improve the corrosion resistance to the N ₂ /O ₂ mixed gas, and also by polar bonds between polymers and/or polar bonds in the polymers. A polymer layer having excellent film density can be formed, and wiggling and/or leaning phenomena of patterns can be reduced.

The B may be further substituted or unsubstituted with other substituents other than the nitro group. The type and number of substituents other than the nitro group are not limited.

For example, B may be further substituted with a hydrophilic functional group, for example, a hydroxyl group, an amino group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C1 to C20 alkylamino group, or a combination thereof. can By including a hydrophilic functional group in B, the solubility of the polymer in a solvent can be effectively applied to a solution process such as spin coating.

For example, B may be further substituted with a hydrogen bondable group, wherein the hydrogen bondable group is as described above. When B further includes a hydrogen bondable group, a polymer layer having excellent film density can be formed by polar bonds between polymers and/or polar bonds within the polymers while increasing the solubility of the polymers in solvents.

For example, B is further substituted with halogen, -OR ^d , -NR ^e R ^f or a combination thereof,

R ^d to R ^f are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, or a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.

For example, R ^d to R ^f are each independently hydrogen, a substituted or unsubstituted methyl group, a substituted or unsubstituted ethyl group, a substituted or unsubstituted propyl group, a substituted or unsubstituted butyl group, a substituted or unsubstituted phen A substituted or unsubstituted hexyl group, a substituted or unsubstituted ethenyl group, a substituted or unsubstituted propenyl group, a substituted or unsubstituted butenyl group, a substituted or unsubstituted pentenyl group, a substituted or unsubstituted hexenyl group , A substituted or unsubstituted ethynyl group, a substituted or unsubstituted propynyl group, a substituted or unsubstituted butynyl group, a substituted or unsubstituted pentynyl group, a substituted or unsubstituted hexynyl group, or a combination thereof.

For example, R ^d may be hydrogen.

For example, at least one of R ^e and R ^f may be hydrogen, and for example, R ^e and R ^f may be hydrogen.

For example, R ^d may be hydrogen, and at least one of R ^e and R ^f may be hydrogen. Accordingly, the hydrogen bondable group included in B is hydrogen-bonded with another structural unit represented by Formula 1 in the polymer and/or a nitro group included in the structural unit represented by Formula 1 in the other polymer, thereby forming a polar bond between the polymers and Or, a polymer layer having excellent film density can be formed by polar bonds in the polymer.

For example, R ^d to R ^f may be hydrogen.

For example, R ^d to R ^f may be the same as or different from each other.

For example, B may be further substituted with -OR ^d , where R ^d is as described above. Accordingly, by increasing the content of oxygen atoms in the structural unit of the polymer, it is possible to simultaneously secure solubility while improving corrosion resistance to N ₂ /O ₂ mixed gas.

For example, B may be further substituted with at least one hydroxyl group.

For example, B is a phenyl group substituted with at least one nitro group and at least one hydroxy group, a naphthyl group substituted with at least one nitro group and at least one hydroxy group, a bi substituted with at least one nitro group and at least one hydroxy group, A phenyl group, a phenanthrenyl group substituted with at least one nitro group and at least one hydroxy group, an anthracenyl group substituted with at least one nitro group and at least one hydroxy group, pi substituted with at least one nitro group and at least one hydroxy group It may be a renyl group, a benzopyrenyl group substituted with at least one nitro group and at least one hydroxy group, a perylenyl group substituted with at least one nitro group and at least one hydroxy group, or a combination thereof.

For example, the structural unit represented by Chemical Formula 1 may be represented by Chemical Formula 2 or 3 below.

[Formula 2]

[Formula 3]

In Formulas 2 and 3,

C is as described above,

R ¹ and R ² are each independently halogen, -OR ^a , -NR ^b R ^c or a combination thereof;

R ³ is a nitro group;

each R ⁴ is independently halogen, -OR ^d , -NR ^e R ^f or a combination thereof;

The R ^a to R ^f are as described above, respectively,

m and n are each independently 0 or 1;

For example, R ^a and R ^d may be hydrogen, at least one of R ^b and R ^c may be hydrogen, and at least one of R ^e and R ^f may be hydrogen.

At least one of R ¹ , R ² and R ⁴ may be a hydroxyl group.

For example, at least one of R ¹ and R ² may be a hydroxyl group.

For example, R ⁴ may be a hydroxyl group.

For example, R ¹ , R ² and R ⁴ may be the same as each other.

For example, R ¹ and R ² may be the same as each other.

For example, R ¹ and R ⁴ may be the same as each other.

For example, at least one of m and n may be 0.

For example, m and n are 0; m is 1 and n is 0; m may be 0 and n may be 1.

The polymer may include one or a plurality of structural units represented by Chemical Formula 1, and a plurality of structural units represented by Chemical Formula 1 may be identical to or different from each other.

The polymer may include a plurality of repeating units of the structural unit represented by Chemical Formula 1, and the number and arrangement of repeating units are not limited.

The polymer may further include one or more other structural units other than the aforementioned structural units, and the number and arrangement of the structural units are not limited.

The polymer may have a weight average molecular weight of about 500 to 200,000. More specifically, the polymer may have a weight average molecular weight of about 800 to 100,000, about 1,000 to 50,000, or about 1,200 to 10,000. By having a weight average molecular weight in the above range, the carbon content of the polymer and the solubility in the solvent can be adjusted and optimized.

On the other hand, the solvent included in the hard mask composition is not particularly limited as long as it has sufficient solubility or dispersibility for the polymer, but for example, propylene glycol, propylene glycol diacetate, methoxy propanediol, diethylene glycol, diethylene glycol butyl Ether, tri(ethylene glycol) monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, gamma-butyrolactone, N,N-dimethylformamide, N,N- It may include at least one selected from dimethylacetamide, methylpyrrolidone, methylpyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate, but is not limited thereto.

The polymer may be included in, for example, about 0.1 to 60% by weight, for example, about 0.5 to 50% by weight, about 1 to 35% by weight, or about 2 to 30% by weight, based on the total amount of the hardmask composition. By including the polymer within the above range, the thickness, surface roughness, and flatness of the hard mask may be adjusted.

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

As the surfactant, for example, fluoroalkyl-based compounds, alkylbenzenesulfonic acid salts, alkylpyridinium salts, polyethylene glycol, quaternary ammonium salts, etc. may be used, but are not limited thereto.

The crosslinking agent may include, for example, melamine-based, substituted urea-based, or these polymer-based. Preferably, a crosslinking agent having at least two cross-linking substituents, for example methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxy Compounds such as methylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or butoxymethylated thiourea can be used.

In addition, as the crosslinking agent, a crosslinking agent having high heat resistance may be used. As the crosslinking agent having high heat resistance, a compound containing a crosslinking substituent having an aromatic ring (for example, a benzene ring or a naphthalene ring) in a molecule may be used.

The thermal acid generator is, for example, an acidic compound such as p-toluenesulfonic acid, trifluoromethanesulfonic acid, pyridinium p-toluenesulfonic acid, salicylic acid, sulfosalicylic acid, citric acid, benzoic acid, hydroxybenzoic acid, naphthalenecarboxylic acid, or/and 2,4 ,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, and other organic sulfonic acid alkyl esters may be used, but are not limited thereto.

The additive may be included in an amount of about 0.001 to 40 parts by weight, about 0.01 to 30 parts by weight, or about 0.1 to 20 parts by weight based on 100 parts by weight of the hard mask composition. When included within the above range, the solubility of the hard mask composition may be improved without changing the optical properties.

According to another embodiment, an organic layer prepared using the hard mask composition described above is provided. The organic film may be formed by coating the above-described hard mask composition on a substrate and then cured through a heat treatment process, and may include, for example, an organic thin film used in electronic devices such as a hard mask layer, a planarization film, a sacrificial film, and a filler. there is.

Hereinafter, a method of forming a pattern using the hard mask composition described above will be described.

A pattern forming method according to an embodiment includes forming a material layer on a substrate, applying a hardmask composition including the above-described polymer and a solvent on the material layer, and heat-treating the hardmask composition to form a hardmask 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, and Exposing a portion of the material layer and etching the exposed portion of the material layer.

The substrate may be, for example, a silicon wafer, a glass substrate or a polymer substrate.

The material layer is a material to be finally patterned, and may be, for example, a metal layer such as aluminum 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 by, for example, a chemical vapor deposition method.

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

The heat treatment of the hardmask composition may be performed at, for example, about 100 to 700° C. for about 10 seconds to 1 hour.

For example, 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, for example, materials such as SiCN, SiOC, SiON, SiOCN, SiC, SiO, and/or SiN.

For example, before 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.

Exposing the photoresist layer may be performed using, for example, ArF, KrF, or EUV. In addition, a heat treatment process may be performed at about 100 to 700° C. after exposure.

Etching the exposed portion of the material layer may be performed by dry etching using an etching gas, such as N ₂ /O ₂ , CHF ₃ , CF ₄ , Cl ₂ , BCl ₃ and a mixture thereof. gas can be used.

The etched material layer may be formed in a plurality of patterns, and the plurality of patterns may be various, such as metal patterns, semiconductor patterns, and insulating patterns, and may be applied as various patterns in a semiconductor integrated circuit device, for example.

The above-described implementation will be described in more detail through the following examples. However, the following examples are for illustrative purposes only and do not limit the scope of rights.

synthesis of polymers

Synthesis Example 1

1-hydroxypyrene (50 g, 0.23 mol) in a 500 ml two-necked flask equipped with a mechanical stirrer and cooling tube. 4- nitrobenzaldehyde (34.6 g, 0.23 mol) and p-toluenesulfonic acid (4.35 g, 0.02 mol) were added, and propylene glycol monomethyl ether acetate was added. , PGMEA, 133 g) was added and mixed, and then stirred at 110° C. for 24 hours. Thereafter, the mixture is cooled to 60 to 70° C. and 300 g of tetrahydrofuran is added to prevent the mixed solution from hardening. After adding 7% sodium bicarbonate solution until the pH of the mixed solution reached 5 to 6, ethyl acetate (1000ml) was added to the mixture while stirring continuously, and the organic layer was extracted using a separatory funnel. Water (500ml) was added to the extracted organic layer, shaken, and the process of washing remaining acid and sodium salt was repeated three or more times, and then the organic layer was finally extracted using a separatory funnel. After concentrating the extracted organic layer with an evaporator, tetrahydrofuran (700 g) was added to obtain a solution. The solution was slowly added dropwise to a beaker containing hexane (3000 ml) while being stirred to obtain a precipitate, and then the precipitate was filtered to obtain Polymer 1 including a structural unit (repeating unit) represented by Formula 1a below.

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight (Mw) was 2,450 and the polydispersity (PD) was 1.47.

[Formula 1a]

Synthesis Example 2

It was synthesized in the same manner as in Synthesis Example 1 except that 1,6-dihydroxypyrene (1,6-dihydroxypyrene, 54 g, 0.23 mol) was used instead of 1-hydroxypyrene (50 g, 0.23 mol), and the following formula Polymer 2 containing the structural unit (repeating unit) represented by 1b was obtained.

[Formula 1b]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 1,430 and the polydispersity was 1.20.

Synthesis Example 3

Same as Synthesis Example 1 except that 4-hydroxy-3-nitrobenzaldehyde (4-hydroxy-3-nitrobenzaldehyde, 38.4 g, 0.23 mol) was used instead of 4-nitrobenzaldehyde (34.6 g, 0.23 mol). Synthesized according to the following method, Polymer 3 including a structural unit (repeating unit) represented by Chemical Formula 1c was obtained.

[Formula 1c]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 3,030 and the polydispersity was 1.58.

Synthesis Example 4

It was synthesized in the same manner as in Synthesis Example 1, except that 1-nitropyrenecarboxaldehyde (1-nitropyrenecarboxaldehyde, 56.9 g, 0.23 mol) was used instead of 4-nitrobenzaldehyde (34.6 g, 0.23 mol) to formula (1d) Polymer 4 containing the structural units (repeating units) represented was obtained.

[Formula 1d]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 1,870 and the polydispersity was 1.28.

Synthesis Example 5

It was synthesized in the same manner as in Synthesis Example 2, except that 1-nitropyrenecarboxaldehyde (1-nitropyrenecarboxaldehyde, 56.9 g, 0.23 mol) was used instead of 4-nitrobenzaldehyde (34.6 g, 0.23 mol) to formula (1e) Polymer 5 containing the structural units (repeating units) represented was obtained.

[Formula 1e]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 1,570 and the polydispersity was 1.24.

Comparative Synthesis Example 1

1-hydroxypyrene (50 g, 0.23 mol) and 1,4-bis (methoxymethyl) benzene (1,4-bis (methoxymethyl) benzene, 38.0 g, 0.23 mol) were sequentially put into a 500 mL flask, and PGMEA (100g) was added and dissolved, and p-toluenesulfonic acid (4.35g, 0.02 mol) was added, followed by stirring at 100° C. for 20 hours to carry out a polymerization reaction. It was checked every 1 hour, and when the weight average molecular weight was 2,500 to 2,600, the reaction was completed to obtain Polymer A including structural units (repeating units) represented by Formula A below.

[Formula A]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 2,500 and the polydispersity was 1.54.

Comparative Synthesis Example 2

1-Hydroxypyrene (50 g, 0.23 mol) and benzaldehyde (24.3 g, 0.23 mol) were sequentially put in a 500 mL flask, PGMEA (130 g) was added and dissolved, and p-toluenesulfonic acid (13.1 g, 0.07 mol) was added. Into the mixture, and stirred at 110 ° C. for 24 hours to carry out a polymerization reaction. It was checked every 1 hour, and when the weight average molecular weight was 3,000 to 3,500, the reaction was completed to obtain Polymer B including structural units (repeating units) represented by Formula B below.

[Formula B]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 3,400 and the polydispersity was 1.61.

Comparative Synthesis Example 3

It was synthesized in the same manner as in Synthesis Example 1, except that 4-hydroxybenzaldehyde (4-hydroxybenzaldehyde, 28.0 g, 0.23 mol) was used instead of 4-nitrobenzaldehyde (34.6 g, 0.23 mol), and represented by the following formula C Polymer C including structural units (repeating units) to be obtained was obtained.

[Formula C]

As a result of analyzing the obtained polymer using gel permeation chromatography (GPC), the weight average molecular weight was 2,650 and the polydispersity was 1.84.

Evaluation 1. Solubility evaluation

Each of the polymers obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 to 3 was added to 20 g of PGMEA and 20 g of propylene glycol monomethyl ether (PGME), respectively, and the mass of the dissolved polymer was measured. .

From the mass of the dissolved polymer, the solubility was calculated by Equation 1 below.

[Calculation 1]

Solubility (%) = (mass of dissolved polymer/amount of solvent (20 g)) x 100

The results are shown in Table 1 below.

Solubility in PGMEA Solubility in PGME Synthesis Example 1 51 55 Synthesis Example 2 43 49 Synthesis Example 3 50 54 Synthesis Example 4 30 29 Synthesis Example 5 32 34 Comparative Synthesis Example 1 15 6 Comparative Synthesis Example 2 22 13 Comparative Synthesis Example 3 10 30

Referring to Table 1, it can be confirmed that the polymers according to Synthesis Examples 1 to 5 have improved solubility in the PGMEA solvent and improved or equivalent solubility in the PGME solvent compared to the polymers according to Comparative Synthesis Examples 1 to 3. .

Evaluation 2. Evaluation of storage stability

After dissolving each of the polymers obtained in Synthesis Examples 1 to 5 and Comparative Synthesis Examples 1 to 3 at 10% by weight in a PGMEA/PGME mixed solvent at a volume ratio of 7:3, in an oven at 40° C. where far ultraviolet rays are blocked, for one month. After storage, gel permeation chromatography was measured, and it was judged as 'X' if there was a change in the trend curve and 'O' if there was no change.

The results are shown in Table 2 below.

storage stability Synthesis Example 1 ○ Synthesis Example 2 ○ Synthesis Example 3 ○ Synthesis Example 4 ○ Synthesis Example 5 ○ Comparative Synthesis Example 1 X Comparative Synthesis Example 2 X Comparative Synthesis Example 3 X

Referring to Table 2, it can be seen that the polymers according to Synthesis Examples 1 to 5 have improved storage stability compared to the polymers according to Comparative Synthesis Examples 1 to 3.

Formation of Hardmask Composition

Examples 1 to 5

1.2 g of each of the polymers obtained in Synthesis Examples 1 to 5 were weighed and uniformly dissolved in 10 g of a PGMEA/PGME mixed solvent having a volume ratio of 7:3, filtered through a 0.1 μm Teflon filter, and hardened to each of Examples 1 to 5. A mask composition was prepared.

Comparative Examples 1 to 3

1.2 g of each of the polymers obtained in Comparative Synthesis Examples 1 to 3 were weighed and uniformly dissolved in 10 g of a PGMEA/cyclohexanone mixed solvent having a volume ratio of 7:3, and filtered through a 0.1 μm Teflon filter to obtain Comparative Examples 1 to 3, respectively. A hard mask composition of 3 was prepared.

Evaluation 3. Erosion resistance evaluation

After spin-coating the hard mask composition according to Examples 1 to 5 and Comparative Examples 1 to 3 on a silicon wafer, heat treatment was performed on a hot plate at about 400° C. for 2 minutes to form an organic film having a thickness of about 4,000 Å. did The thickness of the organic film was measured with K-MAC's ST5000 thin film thickness meter.

Subsequently, N ₂ /O ₂ mixed gas (50mT/300W/10O ₂ /50N ₂ ) was applied to the organic layer for 60 seconds, respectively. After dry etching, the thickness of the organic film was measured again.

A bulk etch rate (BER) was calculated from the difference in thickness of the organic film before and after dry etching and the etching time by Equation 2 below.

[Calculation 2]

Etch rate (Å/s) = (initial organic film thickness - organic film thickness after etching) / etching time

The results are shown in Table 3.

Bulk etch rate (Å/s) Example 1 23.0 Example 2 22.3 Example 3 22.5 Example 4 21.5 Example 5 19.6 Comparative Example 1 25.3 Comparative Example 2 24.1 Comparative Example 3 23.3

Referring to Table 3, the organic films prepared from the hardmask compositions according to Examples 1 to 5 have sufficient etching resistance to etching gas compared to the organic films prepared from the hardmask compositions according to Comparative Examples 1 to 3, thereby improving the etching resistance. You can see this improvement.

Evaluation 4. Membrane Density

After spin-coating the hardmask compositions according to Examples 1 to 5 and Comparative Examples 1 to 3 on silicon wafers, respectively, heat treatment was performed at about 400° C. for about 2 minutes on a hot plate to form an organic film having a thickness of about 1,000 Å. did

The film density of the formed organic film was measured using X-ray diffraction equipment (PANalytical Co.).

The results are shown in Table 4.

Film Density (g/cm ³ ) Example 1 1.38 Example 2 1.46 Example 3 1.48 Example 4 1.43 Example 5 1.50 Comparative Example 1 1.36 Comparative Example 2 1.35 Comparative Example 3 1.37

Referring to Table 4, it can be confirmed that the organic film formed from the hardmask composition according to Examples 1 to 5 has improved film density compared to the organic film formed from the hardmask composition according to Comparative Examples 1 to 3.

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 of those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It falls within the scope of the right of invention.

Claims (14)

A polymer comprising a structural unit represented by Formula 1 below, and
Hardmask composition comprising a solvent:
[Formula 1]

In Formula 1,
A is an aromatic ring selected from the following group 1-1 and substituted with at least one hydrogen bondable group,
B is a C6 to C30 aryl group substituted with at least one nitro group,
C is hydrogen, Deuterium, a hydroxyl group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof:
[Group 1-1]

delete delete In paragraph 1,
A is a hard mask composition selected from Group 2 below:
[Group 2]

In the group 2 above,
R ¹ and R ² are hydrogen bondable groups.
In paragraph 1,
The hydrogen bondable group is halogen, -OR ^a , -NR ^b R ^c or a combination thereof,
Wherein R ^a to R ^c are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.
In paragraph 5,
R ^a is hydrogen;
A hardmask composition wherein at least one of R ^b and R ^c is hydrogen.
In paragraph 1,
B is a hard mask composition selected from Group 3 below and substituted with at least one nitro group.
[Group 3]

In paragraph 1,
B is further substituted with halogen, -OR ^d , -NR ^e R ^f or a combination thereof;
R ^d to R ^f are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, or a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof.
In paragraph 8,
R ^d is hydrogen;
A hardmask composition wherein at least one of R ^e and R ^f is hydrogen.
In paragraph 1,
The structural unit represented by Chemical Formula 1 is a hard mask composition represented by Chemical Formula 2 or 3:
[Formula 2]

[Formula 3]

In Formulas 2 and 3,
C is hydrogen, heavy hydrogen, a hydroxyl group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof;
R ¹ and R ² are each independently halogen, -OR ^a , -NR ^b R ^c or a combination thereof;
R ³ is a nitro group;
each R ⁴ is independently halogen, -OR ^d , -NR ^e R ^f or a combination thereof;
Wherein R ^a to R ^f are each independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocyclic group, or a combination thereof;
m and n are each independently 0 or 1;
In paragraph 10,
R ^a and R ^d are hydrogen;
at least one of R ^b and R ^c is hydrogen;
A hardmask composition wherein at least one of R ^e and R ^f is hydrogen.
In paragraph 10,
A hardmask composition wherein at least one of R ¹ , R ² and R ⁴ is a hydroxyl group.
In paragraph 10,
A hardmask composition in which at least one of m and n is 0.
Forming a hard mask layer by applying a hard mask composition according to any one of claims 1 and 4 to 13 on a material layer and heat-treating;
forming a photoresist layer over the hard mask layer;
Exposing and developing the photoresist layer to form a photoresist pattern;
selectively removing the hard mask layer using the photoresist pattern and exposing a portion of the material layer; and
Etching the exposed portion of the material layer
Pattern forming method comprising a.