KR101812764B1 - Composition for hard mask - Google Patents

Abstract

The present invention relates to a composition for hard mask. The composition for hard mask comprises: a polymer which consists of a first unit containing at least one of a pyrene-based unit or a carbazole-based unit and a second unit which includes a tolyl group or a biphenyl group; and a solvent. According to the present invention, the composition for hard mask enables production of hard mask with enhanced flatness, solubility, and etching resistance.

Description

COMPOSITION FOR HARD MASK [0001]

The present invention relates to a composition for a hard mask. More particularly, the present invention relates to compositions for hard masks comprising aromatic condensates or compounds.

For example, in the fields of semiconductor manufacturing, microelectronics, etc., the degree of integration of structures such as circuits, wiring lines, insulation patterns and the like is continuously improving. Accordingly, a photolithography process for fine patterning of the structures has been developed at the same time.

Generally, a photoresist is applied on a film to be etched to form a photoresist layer, and a photoresist pattern is formed through exposure and development. Then, a predetermined pattern can be formed by partially removing the film to be etched by using the photoresist pattern as an etching mask. After the image transfer to the etch target film is performed, the photoresist pattern may be removed through an ashing and / or strip process.

An anti-reflection coating (ARC) layer may be formed between the etch target film and the photoresist layer to suppress the resolution degradation due to light reflection during the exposure process. In this case, the etching for the ARC layer is added, so that the consumption amount or the etching amount of the photoresist layer or the photoresist pattern can be increased. Further, when the thickness of the etching target film increases or the etching amount required for forming a desired pattern increases, sufficient etching resistance of the photoresist layer or the photoresist pattern may not be ensured.

Thus, a resist undercoat may be added between the etch target film and the photoresist layer to ensure etch resistance and etch selectivity of the photoresist for desired pattern formation.

The resist under film needs to have sufficient resistance to etching (or etching resistance) and heat resistance, for example, for a high-temperature etching process, and also to be formed to have a uniform thickness by, for example, a spin-on coating process .

Korean Patent Laid-Open No. 10-2010-0082844 discloses an example of a composition for forming a resist lower film.

Korean Patent Publication No. 10-2010-0082844

An object of the present invention is to provide a composition for a hard mask capable of forming a hard mask having excellent mechanical and chemical properties and having a uniform profile.

1. A polymer comprising a first unit comprising at least one of pyrene-based units or carbazole-based units, and a second unit containing a tolyl group or biphenyl group; And

A composition for a hard mask, comprising:

[Chemical Formula 1]

(Wherein Ar ₁ represents the first unit, Ar ₂ represents the second unit, and n represents an integer of 2 to 100).

2. The hard mask composition according to 1 above, wherein the first unit is derived from at least one aromatic compound selected from the following formulas (2) and (3)

(2)

(3)

(In the formula (3), Ar is an aromatic hydrocarbon group having 6 to 12 carbon atoms).

3. The composition for a hard mask according to 2 above, wherein the compound represented by the formula (3) comprises at least one of the compounds represented by the following formulas (3-1) to (3-3)

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

.

.

4. The hard mask composition according to 1 above, wherein the second unit is derived from a compound represented by the following formula (4) or a synthetic equivalent thereof:

[Chemical Formula 4]

(Wherein R is methyl or phenyl).

5. The composition for a hard mask according to 4 above, wherein the synthetic equivalent comprises a tolyl group or an acetal compound containing a biphenyl group.

6. The composition for hard mask according to 1 above, wherein the polymer is composed of only the first unit and the second unit.

7. The composition of claim 1, further comprising at least one of a crosslinking agent, a catalyst or a surfactant.

By using the composition for a hard mask according to the embodiments of the present invention, it is possible to form a hard mask having excellent flatness, solubility, etch resistance and heat resistance at the same time.

The composition for a hard mask according to embodiments of the present invention may include a polymer prepared by condensing an aromatic compound and an aldehyde linker compound linked with a tolyl group or a biphenyl group. Thus, the reactivity can be improved and the solubility of the linker compound or polymer can be increased. Therefore, the flatness and the gap-fill characteristics of the hard mask formed from the composition for a hard mask can be improved together.

In addition, pyrene or carbazole-based compounds may be used as the aromatic compound. Therefore, a polymer having a high carbon content can be produced, so that the heat resistance and etching resistance of the hard mask can be improved.

In addition, a high-resolution photolithography process can be realized using the hard mask formed from the composition for hard mask, and a target pattern having a desired fine line width can be formed.

Embodiments of the present invention are directed to a composition for a hard mask comprising a polymer of a linker compound comprising a pyrene or carbazole based compound and a tolylaldehyde or biphenylaldehyde and thus having improved solubility, to provide. The composition for a hard mask may be formed, for example, between a photoresist layer and a film to be etched to form a hard mask film utilized as a resist lower film. The hard mask film may be partially removed through a photoresist pattern to form a hard mask, and the hard mask may be used as an additional etching mask.

The hard mask film or the hard mask may be utilized, for example, as a spin-on hard mask (SOH).

Hereinafter, the composition for a hard mask according to embodiments of the present invention will be described in detail. When a compound or an isomer of a resin represented by the formula used in the present application is present, the compound or the resin represented by the formula means a representative formula including the isomer thereof.

The composition for a hard mask according to embodiments of the present invention includes a polymer and a solvent, and may further include an additional agent such as a cross-linking agent, a catalyst, and the like.

polymer

According to the embodiments of the present invention, the polymer contained in the composition for hard mask includes a first unit including at least one of a pyrene series unit or a carbazole series unit, and a second unit including a tolyl group or biphenyl group .

According to exemplary embodiments, the polymer may comprise a structure represented by the following formula (1).

[Chemical Formula 1]

In the general formula (1), Ar ₁ may represent the above-mentioned first unit. Ar ₂ may represent the second unit, for example, a tolyl group or a biphenyl group. and n may be an integer of 2 to 200.

The unit structure indicated by parentheses in the formula (1) may be continuously repeated, and the first unit and / or the second unit may be inserted between each unit. In some embodiments, the first unit, denoted Ar _1, is comprised in the backbone structure of the polymer and the second unit denoted Ar ₂ is a pendant or moiety of the polymer. . Formula (1) represents a conceptual structural formula that exemplifies the above-described unit structure of the first unit and the second unit.

In some embodiments, the polymer is substantially comprised of Ar < _{1 >} and Ar < ₂ &_gt;, but may not include other monomers.

For example, the first unit is derived from an aromatic compound described later, and the second unit may be derived from a linker compound described later. In this case, the polymer may be an oligomer of the aromatic compound and the linker compound.

Aromatic compound

The aromatic compound can be used as a base material of the polymer. According to exemplary embodiments, pyrene-based compounds or carbazole-based compounds may be used as the aromatic compounds.

The pyrene-based compound may include pyrene represented by the following formula (2).

(2)

By using a pyrene containing a hydroxy group, the cross-linking reaction between the polymers is promoted, so that the heat resistance and etching resistance of the hard mask can be improved.

The carbazole-based compound may be represented by, for example, the following formula (3).

(3)

In the formula (3), Ar may be an aromatic hydrocarbon group having 6 to 12 carbon atoms. Preferably, Ar is phenyl, naphthyl or biphenyl. When the carbon number of Ar is more than 12, the solubility of the polymer is excessively decreased, which may deteriorate the flatness and the capillary property of the hard mask.

For example, the carbazole-based compound may include at least one of the following compounds represented by the following formulas (3-1) to (3-3).

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

By using the above-mentioned pyrene-based or carbazole-based compound as the aromatic compound, it is possible to secure adequate solubility while increasing the carbon content of the polymer. As used herein, the term "carbon content" may refer to the ratio of carbon mass to total mass per molecule of a compound.

According to exemplary embodiments, at least one compound selected from the above-mentioned chemical formulas 2 and 3 may be used as the aromatic compound.

Linker compound

According to the embodiments of the present invention, the linker compound may include a tolyl group or a biphenyl group-containing compound.

Examples of the linker compound include an aldehyde or a synthetic equivalent thereof, a ketone or an alcohol compound, which is linked with a tolyl group or a biphenyl group. From the viewpoint of reactivity with the aromatic compound, tolylaldehyde or biphenylaldehyde or a synthetic equivalent thereof may be used.

In this case, the linker compound may be represented by the following formula (4).

[Chemical Formula 4]

In formula (4), R is methyl or phenyl. Preferably, the linker compound is 4-methylbenzaldehyde and 4-phenylbenzaldehyde.

When the linker compound does not contain R (for example, benzaldehyde), the solubility is lowered, and the flatness and gap-fill characteristics of the hard mask can be deteriorated. Also, even when R is an alkyl group having two or more carbon atoms, the solubility is lowered, and the etching resistance and heat resistance of the hard mask can be deteriorated due to a decrease in the carbon content.

When the linker compound comprises a biphenyl group, the flexibility of the linker compound or the polymer can be improved due to the rotatable structure between the two benzene rings. In addition, since the carbon content is increased, the flatness, etch resistance, and heat resistance of the hard mask can be improved.

When R in formula (4) includes an aryl ring having more than 6 carbon atoms, the solubility is excessively lowered and the desired flatness may not be secured.

Examples of the synthesis equivalent of the aldehyde compound represented by the general formula (4) include acetyl compounds containing a tolyl group or a biphenyl group. For example, as the above synthetic equivalent, compounds of the following formulas (5-1) to (5-4) may be mentioned.

[Formula 5-1]

[Formula 5-2]

[Formula 5-3]

[Formula 5-4]

The polymer can be prepared by the condensation reaction of the aromatic compound and the linker compound described above. In some embodiments, the polymer may be prepared using only the aromatic compounds and linker compounds described above, and other aromatic compounds or linker compounds may not be used in the preparation of the polymer. Therefore, it is possible to prevent the flatness, the etch resistance, and the solubility degradation due to the addition of other compounds and ensure desired properties.

For example, the aromatic compound and the linker compound may be used in a molar ratio ranging from about 1: 0.5 to 1: 1, but are not limited thereto.

As described above, according to the embodiments of the present invention, since an aldehyde compound linked with, for example, a tolyl group or a biphenyl group is used as the linker compound, the solubility of the linker compound or the polymer is improved along with the improvement of the reactivity, The flatness and the gap-fill characteristics of the semiconductor device can be improved.

In addition, a pyrene or carbazole-based compound may be used as the aromatic compound to obtain a polymer having a high carbon content. Therefore, the heat resistance and the etch resistance of the desired hard mask can be ensured without impairing the solubility and flatness of the polymer.

In the embodiments of the present invention, the content of the polymer is not particularly limited, but may be, for example, about 10 to 50% by weight of the total weight of the composition for a hard mask.

In one embodiment, the weight average molecular weight of the polymer may be in the range of, for example, about 1,000 to 10,000, and desirable heat resistance, etch resistance, solubility, and flatness can be secured within the above range.

In one embodiment, the polydispersity index (PDI) (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the polymer can be from about 1.5 to 6.0, preferably from about 1.5 to 4.0 . Within the above range, desirable heat resistance, etching resistance, solubility and flatness can be secured at the same time.

menstruum

The solvent used in the composition for a hard mask according to the embodiments of the present invention is not particularly limited and may include an organic solvent having sufficient solubility in the polymer of the above aromatic compound. For example, the solvent may be selected from the group consisting of propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, ethyl lactate, gamma-butyrolactone gamma -butyrolactone (GBL), acetyl acetone, and the like.

The content of the solvent is not particularly limited, and may be included in the remaining amount excluding the polymer of the aromatic compound and the additional agents described below. For example, the solvent may comprise from 30 to 90% by weight of the total weight of the composition for a hard mask.

Additional formulations

Optionally, the composition for a hard mask according to embodiments of the present invention may further comprise additional agents such as crosslinking agents, catalysts, and surfactants.

The crosslinking agent is capable of crosslinking the repeating unit of the polymer of the aromatic compound and can react with, for example, the hydroxyl group of the polymer. By the crosslinking agent, the curing property of the composition for a hard mask can be further strengthened.

Examples of the cross-linking agent include melamine, an amino resin, a glycoluril compound, and a bis-epoxy compound.

The cross-linking agent may be, for example, an etherified amino resin such as methylated or butylated melamine (specifically N-methoxymethyl-melamine or N-butoxymethyl-melamine) and methylated or butylated (Hydroxymethyl) -p (methoxymethyl) urea resin represented by the following general formula (7), urea resin (specific examples of which are Cymel U-65 Resin or UFR 80 Resin), glycoluril derivatives - cresol compounds and the like. The bis-epoxy compound represented by the following general formula (8) and the melamine-based compound represented by the following general formula (9) can also be used as a crosslinking agent.

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

As the catalyst, an acid catalyst or a basic catalyst may be used.

The acid catalyst may be a thermally activated acid catalyst. As an example of the acid catalyst, an organic acid such as p-toluenesulfonic acid can be used. As the acid catalyst, a thermal acid generator (TAG) system compound may be used. Examples of the thermal acid generator system catalyst include pyridinium p-toluene sulfonate, 2,4,4,6-tetrabromocyclohexadiene, benzoin tosylate, 2-nitrobenzyltosyl Alkyl esters of organic sulfonic acids, and the like.

As the basic catalyst, any one selected from among NH ₄ OH or ammonium hydroxide represented by NR ₄ OH (R is an alkyl group) can be used.

When the cross-linking agent is included, the content of the cross-linking agent may be about 1 to 30 parts by weight, preferably about 5 to 20 parts by weight, more preferably about 5 to 10 parts by weight based on 100 parts by weight of the polymer of the aromatic compound have. When the catalyst is included, the content of the catalyst may be about 0.001 to 5 parts by weight, preferably about 0.1 to 2 parts by weight, more preferably about 0.1 to 1 part by weight, per 100 parts by weight of the polymer of the aromatic compound Weight portion.

Appropriate crosslinking properties can be obtained without deteriorating the etching resistance, heat resistance, solubility, and flatness of the polymer of the aromatic compound within the range of the content of the crosslinking agent and the catalyst.

The composition for a hard mask according to the embodiments of the present invention may further include a surfactant for improving the surface property and adhesiveness of the hard mask. As the surfactant, alkylbenzenesulfonate, alkylpyridinium salt, polyethylene glycol, quaternary ammonium salt and the like can be used, but not limited thereto. The amount of the surfactant may be, for example, about 0.1 to 10 parts by weight based on 100 parts by weight of the polymer of the aromatic compound.

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. It will be apparent to those skilled in the art that various changes and modifications can be made to the embodiments within the spirit and scope of the appended claims.

Examples and Comparative Examples

A composition for a hard mask of the composition and the content (% by weight) shown in Table 1 below was prepared. In Examples and Comparative Examples, para-toluenesulfonic acid (5 mol% based on the aromatic compound) was used as an acid catalyst in the formation of the polymer (A).

division Polymer (A) Solvent (B) The crosslinking agent (C) The catalyst (D) Surfactants
(E) ingredient content ingredient content ingredient content ingredient content ingredient content Example 1 A-1 10 B-1 90 - - - - - - Example 2 A-2 10 B-1 90 - - - - - - Example 3 A-3 10 B-1 90 - - - - - - Example 4 A-4 10 B-1 90 - - - - - - Example 5 A-5 10 B-1 90 - - - - - - Example 6 A-6 10 B-1 90 - - - - - - Example 7 A-7 10 B-1 90 - - - - - - Example 8 A-8 10 B-1 90 - - - - - - Example 9 A-1 10 B-1 88 C-1 One D-1 One - - Example 10 A-1 10 B-1 89 - - - - E-1 One Example 11 A-9 10 B-1 90 - - - - - - Example 12 A-10 10 B-1 90 - - - - - - Example 13 A-11 10 B-1 90 - - - - - - Example 14 A-12 10 B-1 90 - - - - - - Example 15 A-13 10 B-1 90 - - - - - - Example 16 A-14 10 B-1 90 - - - - - - Comparative Example 1 A'-1 10 B-1 90 - - - - - - Comparative Example 2 A'-2 10 B-1 90 - - - - - - Comparative Example 3 A'-3 10 B-1 90 - - - - - - Comparative Example 4 A'-4 10 B-1 90 - - - - - - Comparative Example 5 A'-5 10 B-1 90 - - - - - - Comparative Example 6 A'-6 10 B-1 90 - - - - - - Comparative Example 7 A'-7 10 B-1 90 - - - - - -

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3800)A-1:

,

(Weight-average molecular weight: 3800) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4100)A-2:

,

(Weight-average molecular weight: 4100) produced by a condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3200)A-3:

,

(Weight-average molecular weight: 3200) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4500)A-4:

,

(Weight-average molecular weight: 4,500) produced by a condensation reaction in a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4300)A-5:

,

(Weight-average molecular weight: 4300) produced by a condensation reaction in a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4000)A-6:

,

(Weight-average molecular weight: 4000) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 5500)A-7:

,

(Weight-average molecular weight: 5,500) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4500)A-8:

,

(Weight-average molecular weight: 4,500) produced by a condensation reaction in a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3500)A-9:

,

(Weight-average molecular weight: 3500) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 5600)A-10:

,

(Weight-average molecular weight: 5600) produced by a condensation reaction at a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4100)A-11:

,

(Weight-average molecular weight: 4100) produced by a condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4500)A-12:

,

(Weight-average molecular weight: 4,500) produced by a condensation reaction in a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4400)A-13:

,

(Weight-average molecular weight: 4400) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 4000)A-14:

,

(Weight-average molecular weight: 4000) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3400)A'-1:

,

(Weight-average molecular weight: 3400) produced by the condensation reaction at a molar ratio (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3800)A'-2:

,

(Weight-average molecular weight: 3800) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3800)A'-3:

,

(Weight-average molecular weight: 3800) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 3800)A'-4:

,

(Weight-average molecular weight: 3800) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 2500)A'-5:

,

(Weight-average molecular weight: 2500) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 5300)A'-6:

,

(Weight-average molecular weight: 5,300) produced by the condensation reaction of ethylene (1: 1 molar ratio)

,

(1:1 몰비율)의 축합반응으로 생성된 공중합체(중량평균분자량: 5000)A'-7:

,

(Weight average molecular weight: 5,000) produced by a condensation reaction at a molar ratio (1: 1 molar ratio)

B-1: PGMEA

C-1: N-methoxymethyl-melamine resin

D-1: p-toluenesulfonic acid-pyridine salt

E-1: Triethylene glycol

Experimental Example

The etchability, solubility and flatness of the hard mask layer or the hard mask formed from the compositions shown in Table 1 were evaluated by the following evaluation method. The evaluation results are shown in Table 2 below.

(1) Evaluation of etchability

The compositions according to Examples and Comparative Examples were respectively coated on a silicon wafer by spin coating and baked at 200 DEG C for 60 seconds to form a film having a thickness of 1500 ANGSTROM. Each of the formed films was coated with ArF photoresist, baked at 110 ° C for 60 seconds, exposed using ASML (XT: 1450G, NA 0.93) exposure equipment, and developed with TMAH (2.38 wt% aqueous solution) A line-and-space pattern of 60 nm was obtained.

The patterned specimens obtained, and further cured at 110 ℃ 60 seconds, and the test piece using a CHF ₃ / CF ₄ gas mixture proceeds dry etching 20 seconds, respectively, and by observing the cross section by FE-SEM, respectively to measure the etching rate The etch resistance to the halogen plasma was evaluated.

≪ Determination of etchability &

◎: Etching rate less than 10 A / sec

○: Etching rate 10 A / sec or more and less than 11 A / sec

DELTA: etching rate of 11 A / sec or more and less than 12 A / sec

×: etching rate of 12 A / sec or more

(2) Solubility

The compositions according to the examples and comparative examples in Table 1 were spin-coated after drying to a thickness of 5 탆, dried at 100 캜 in a hot-air drier for 3 minutes, and then visually inspected. The solubility of the polymer was evaluated through the uniformity of the coating film.

≪ Determination of solubility &

○: Unevenness of coating surface is not visually confirmed.

?: Local irregularity was visually confirmed.

×: Unevenness on the front surface was visually confirmed.

(3) Flatness evaluation

The compositions of Examples and Comparative Examples were coated on a SiO ₂ wafer substrate having a trench width of 10 μm and a depth of 0.50 μm and dried to form a hard mask film. The thickness difference between the trench portion and the non-trench portion was measured by a scanning electron microscope (SEM) to evaluate flatness.

≪ Flatness judgment &

?: Thickness difference less than 150 nm

DELTA: Thickness difference 150 to 200 nm

X: Thickness difference exceeding 200 nm

division Etchability Solubility Flatness Example 1 ○ ○ ○ Example 2 ○ ○ ○ Example 3 ○ ○ ○ Example 4 ◎ ○ ○ Example 5 ◎ ○ ○ Example 6 ○ ○ ○ Example 7 ◎ ○ ○ Example 8 ◎ ○ ○ Example 9 ◎ ○ ○ Example 10 ○ ○ ○ Example 11 ○ ○ ○ Example 12 ◎ △ △ Example 13 ○ ○ ○ Example 14 ◎ ○ ○ Example 15 ◎ ○ ○ Example 16 ◎ ○ ○ Comparative Example 1 ◎ X △ Comparative Example 2 △ △ △ Comparative Example 3 △ △ △ Comparative Example 4 X △ △ Comparative Example 5 X ○ ○ Comparative Example 6 X ○ ○ Comparative Example 7 ◎ X X

Referring to Table 2, overall excellent etching resistance, solubility, and flatness were obtained in the examples in which the aromatic compounds and linker compounds disclosed in the present application were used as compared with the comparative examples.

On the other hand, when biphenylaldehyde was used as the linker compound in Examples 4 and 5, the etch resistance was further improved in Examples 1 to 3 as the carbon content increased. Further, by using carbazole-based compounds in which naphthyl or biphenyl is substituted as an aromatic compound in Examples 7 and 8, the etch resistance of Examples 1 to 3 was further improved by increasing the carbon content.

In the case of Example 9, by using the crosslinking agent and the catalyst together, the etching resistance was further increased by the improvement of the degree of crosslinking compared to Example 1. [

In Example 11, a carbazole-based compound having no substituent group at the nitrogen atom was used, and the etching resistance was somewhat lowered than in Examples 7 and 8. In the case of Example 12, the solubility and flatness were somewhat reduced as the number of carbon atoms of the substituent bonded to the nitrogen atom was increased as compared with Examples 7 and 8.

In Examples 13 to 16 in which an acetal compound was used as a linker compound as an organosilicon compound such as aldehyde, etch resistance, solubility, and flatness were excellent as compared with Comparative Examples.

In the case of Comparative Examples 1 and 7, solubility was excessively decreased as benzaldehyde without an alkyl substituent was used as a linker compound. Further, in Comparative Examples 2 and 3, the use of benzaldehyde containing an ethyl substituent or two methyl substituents was used to reduce the etch resistance due to the decrease in the carbon content, and the solubility and flatness were also lowered in comparison with the examples.

In Comparative Example 4, as the number of carbon atoms and the number of substituents of the benzaldehyde increased, the etch resistance further decreased due to the decrease of the carbon content. In the case of Comparative Examples 5 and 6, the etching resistance was deteriorated due to the use of an aromatic compound having a low carbon content.

Claims (7)

A polymer comprising a first unit derived from a compound represented by the following formula (3), and a second unit containing a tolyl group or a biphenyl group; And
A composition for a hard mask, comprising:
[Chemical Formula 1]

(Wherein Ar ₁ represents the first unit, Ar ₂ represents the second unit, and n represents an integer of 2 to 100)
(3)

(In the formula (3), Ar is an aromatic hydrocarbon group having 6 to 12 carbon atoms).
delete The composition for a hard mask according to claim 1, wherein the compound represented by the formula (3) comprises at least one of compounds represented by the following formulas (3-1) to (3-3)
[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

.
The hard mask composition according to claim 1, wherein the second unit is derived from a compound represented by the following formula (4) or a synthetic equivalent thereof:
[Chemical Formula 4]

(Wherein R is methyl or phenyl).
5. The composition for a hard mask according to claim 4, wherein the synthetic equivalent comprises a tolyl group or a biphenyl group-containing acetal compound.
The composition for a hard mask according to claim 1, wherein the polymer is composed only of the first unit and the second unit.
The composition of claim 1, further comprising at least one of a crosslinking agent, a catalyst, or a surfactant.