KR102222780B1 - Organic layer composition, and method of forming patterns - Google Patents

Abstract

[화학식 2]

상기 화학식 1 및 2의 정의는 명세서 내에 기재한 바와 같다.An organic film composition according to an embodiment relates to an organic film composition comprising a polymer including a structural unit represented by Formula 1 below, a crosslinking agent represented by Formula 2 below, and a solvent.
[Formula 1]

[Formula 2]

The definitions of Formulas 1 and 2 are as described in the specification.

Description

Organic film composition and pattern formation method {ORGANIC LAYER COMPOSITION, AND METHOD OF FORMING PATTERNS}

It relates to an organic film composition, and a pattern forming method using the organic film composition.

Recently, the semiconductor industry is developing from a pattern of several hundred nanometers to an ultra-fine technology having a pattern of several to tens of nanometers. Effective lithographic techniques are essential to realize such ultra-fine technology.

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

In recent years, as the size of the pattern to be formed decreases, it is difficult to form a fine pattern having a good profile using only the above-described typical lithographic technique. Accordingly, a fine pattern may be formed by forming an organic layer called a hardmask layer between the material layer to be etched and the photoresist layer.

The hard mask layer serves as an interlayer that transfers the fine pattern of the photoresist to the material layer through a selective etching process. Therefore, the hard mask layer needs heat resistance and corrosion resistance so that it can withstand multiple etching processes.

On the other hand, in recent years, it has been proposed to form a hardmask layer by a spin-on coating method instead of a chemical vapor deposition method. The spin-on coating method is not only easy to process, but also improves gap-fill characteristics and planarization characteristics. In order to realize a fine pattern, it is necessary to form multiple patterns, and at this time, a buried property of filling the inside of the pattern with a film without voids is required. In addition, when there is a step difference in the substrate to be processed, or when a pattern dense portion and an area without a pattern exist together on the wafer, it is necessary to flatten the film surface by the lower layer film.

There is a need for an organic film material capable of satisfying the characteristics required for the above-described hardmask layer.

One embodiment provides an organic film composition having excellent planarization properties and gap-fill properties when applied by a spin-coating method while securing etch resistance.

Another embodiment provides a pattern formation method using the organic film composition.

According to an embodiment, a polymer comprising a structural unit represented by the following formula (1),

It provides an organic film composition comprising a crosslinking agent represented by the following formula (2) and a solvent.

[Formula 1]

In Formula 1,

A ¹ is a divalent cyclic group containing at least one substituted or unsubstituted benzene ring,

B ¹ is a divalent organic group,

* Is the point of connection;

[Formula 2]

In Chemical Formula 2,

L is a divalent organic group containing two double bonds or two triple bonds,

X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,

a and b are each independently an integer of 0 to 4.

The crosslinking agent may be represented by the following Chemical Formula 3 or 4.

[Formula 3]

[Formula 4]

In Chemical Formulas 3 and 4,

X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,

a and b are each independently an integer of 0 to 4,

c to f are each independently an integer of 0 to 5.

In Formulas 3 and 4, the sum of a and b may be 1 or more.

In Formulas 3 and 4, a and b may each independently be an integer of 1 to 4.

In Formula 3, c and d are each independently an integer of 1 to 4, and in Formula 4, e and f may each independently be an integer of 1 to 4.

In Formula 1, A ¹ may be a divalent cyclic group including at least two rings in its structure.

In Formula 1, A ¹ is a divalent cyclic group derived from any one of the compounds listed in Groups 1 and 2 below, and the divalent cyclic group may be substituted or unsubstituted with at least one hydrogen atom.

[Group 1]

[Group 2]

In group 1 above,

M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl,

In group 2 above,

R ⁰ and R ¹ are each independently hydrogen, a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a It is a combination.

In Formula 1, B ¹ may be represented by the following Formula 4.

[Formula 4]

In Chemical Formula 4,

m and n are each independently an integer of 0 to 2,

Z is a divalent cyclic group derived from any one selected from the following group 3, and the divalent cyclic group is a group in which at least one hydrogen atom is substituted or unsubstituted,

* Is the point of connection:

[Group 3]

In group 3 above,

M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl.

The polymer and the crosslinking agent may be included in an amount of 40:60 to 80:20 by weight.

The organic layer composition may further include a thermal acid generator.

According to another embodiment, the step of forming a material layer on a substrate, applying the above-described organic film composition on the material layer, forming a hardmask layer by heat treatment of the organic film composition, on the hardmask layer Forming a silicon-containing thin film layer, forming a photoresist layer on the silicon-containing thin film layer, exposing and developing the photoresist layer to form a photoresist pattern, the silicon-containing thin film layer and It provides a pattern forming method comprising selectively removing the hardmask layer, exposing a portion of the material layer, and etching the exposed portion of the material layer.

The step of applying the organic film composition may be performed by a spin-on coating method.

It may further include forming a bottom anti-reflective layer (BARC) before forming the photoresist layer.

The organic film composition according to the present invention can provide an organic film composition having excellent planarization characteristics and gap-fill characteristics when applied by a spin-coating method while securing etch resistance.

1 is a flow chart for explaining a pattern forming method according to an embodiment,
2 is a reference diagram for explaining a method of evaluating planarization characteristics.

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

Unless otherwise defined herein, the term'substituted' means that the hydrogen atom in the compound is a halogen atom (F, Br, Cl, or I), a hydroxy 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 salt thereof, sulfonic acid group or salt thereof, phosphoric acid or salt thereof, C1 to C30 alkyl group, C2 to C30 alkenyl group, C2 to C30 alky Nyl group, C6 to C30 aryl group, C7 to C30 arylalkyl group, C1 to C30 alkoxy group, C1 to C20 heteroalkyl group, C3 to C20 heteroarylalkyl group, C3 to C30 cycloalkyl group, C3 to C15 cycloalkenyl group, C6 to C15 It means substituted with a substituent selected from a cycloalkynyl group, a C3 to C30 heterocycloalkyl group, and combinations thereof.

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

In addition, unless otherwise defined in the specification,'*' indicates a connection point of a compound or a compound moiety.

Hereinafter, an organic film composition according to an embodiment will be described.

The organic film composition according to an embodiment includes a polymer including a structural unit represented by Formula 1 below, a crosslinking agent represented by Formula 2 below, and a solvent.

[Formula 1]

In Formula 1,

A ¹ is a divalent cyclic group containing at least one substituted or unsubstituted benzene ring,

B ¹ is a divalent organic group,

* Is the connection point:

[Formula 2]

In Chemical Formula 2,

L is a divalent organic group containing two double bonds or two triple bonds,

X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,

a and b are each independently an integer of 0 to 4.

First, the polymer will be described.

The polymer includes a cyclic group moiety represented by ^{A 1} and a linking group moiety represented by ^{B 1} in the structural unit.

For example, in Formula 1, A ¹ may be a divalent cyclic group containing at least two rings in its structure, for example, as a divalent cyclic group derived from any one of the compounds listed in Groups 1 and 2 below, The divalent cyclic group may be one in which at least one hydrogen atom is substituted or unsubstituted, but is not limited thereto.

[Group 1]

[Group 2]

In group 1 above,

M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl,

In group 2 above,

R ⁰ and R ¹ are each independently hydrogen, a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a It is a combination.

For example, in Formula 1, B ¹ may be represented by Formula 4 below, but is not limited thereto.

[Formula 4]

In Chemical Formula 4,

m and n are each independently an integer of 0 to 2,

Z is a divalent cyclic group derived from any one selected from the following group 3, and the divalent cyclic group is a group in which at least one hydrogen atom is substituted or unsubstituted,

* Is the point of connection:

[Group 3]

In group 3 above,

M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl.

In Formula 4, m and n may each be 1, for example.

In Formula 4, Z is at least such as a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof. It may be substituted by one functional group.

For example, the weight average molecular weight of the polymer may be 1,000 to 200,000, but is not limited thereto.

Next, the crosslinking agent will be described.

As described above, the organic film composition according to the exemplary embodiment includes a crosslinking agent represented by Chemical Formula 2.

The crosslinking agent includes two substituted or unsubstituted benzene rings, and these benzene rings are connected by a divalent organic group. Here, the divalent organic group represented by L contains two double bonds or two triple bonds.

That is, the crosslinking agent has a diene structure, which is two carbon double bonds, or a diyne structure, which is two carbon triple bonds. Accordingly, when the organic film composition is cured, the reaction proceeds toward forming a ring through the Diels-Alder reaction, so etch resistance and heat resistance can be secured.Because the composition does not form a ring before curing, solubility characteristics and spin-coating When applied by the method, flattening properties and gap-fill properties may be excellent.

Scheme 1 below is for explaining the change in the structure of the crosslinking agent during curing of the organic film composition described above.

[Scheme 1]

Referring to Scheme 1, it can be seen that as the Diene structure/Diyne structure in the crosslinking agent is included in the organic film composition, it is possible to simultaneously secure several conflicting physical properties of the organic film composition.

For example, the crosslinking agent may be represented by the following Chemical Formula 3 or 4, but is not limited thereto.

[Formula 3]

[Formula 4]

In Chemical Formulas 3 and 4,

X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,

a and b are each independently an integer of 0 to 4,

c to f are each independently an integer of 0 to 5.

For example, in Formulas 3 and 4, the sum of a and b may be 1 or more, and for example, a and b may each independently be an integer of 1 to 4, but are not limited thereto.

For example, in Formula 3, c and d are each independently an integer of 1 to 4, and in Formula 4, e and f may each independently be an integer of 1 to 4, but are not limited thereto.

The content of the polymer contained in the organic film composition is included in about 0.1 to 50% by weight, about 0.1 to 30% by weight, about 5 to 30% by weight, or about 0.1 to 15% by weight based on the total content of the organic film composition. I can. By including the polymer within the above range, the thickness, surface roughness, and level of planarization of the organic film can be controlled.

The content of the crosslinking agent included in the organic film composition is not limited, but the polymer and the crosslinking agent may be adjusted to be included in a weight ratio of 40:60 to 80:20.

On the other hand, the solvent contained in the organic film composition is not particularly limited as long as it has sufficient solubility or dispersibility in the polymer, 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 contain at least one selected from dimethylacetamide, methylpyrrolidone, methylpyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

The organic film composition may further include additives such as a surfactant, a thermal acid generator, a plasticizer, and a conventional crosslinking agent other than the crosslinking agent represented by Formula 2 above.

The surfactant may be, for example, a fluoroalkyl-based compound, an alkylbenzene sulfonate, an alkylpyridinium salt, a polyethylene glycol, or a quaternary ammonium salt, but is not limited thereto.

The thermal acid generator is 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, benzointosylate, 2-nitrobenzyltosylate, and other organic fonate alkyl esters may be used, but the present invention is not limited thereto.

The additive may be included in an amount of about 0.001 to 40 parts by weight based on 100 parts by weight of the organic layer composition. By including it in the above range, solubility can be improved without changing the optical properties of the organic film composition.

According to another embodiment, an organic film manufactured using the above-described organic film composition is provided. The organic film may be in the form of coating the above-described organic film composition on a substrate, for example, and then cured through a heat treatment process. have.

Hereinafter, a method of forming a pattern using the organic film composition described above will be described with reference to FIG. 1.

1 is a flowchart illustrating a method of forming a pattern according to an exemplary embodiment.

A pattern formation method according to an embodiment includes forming a material layer on a substrate (S1), applying the above-described organic film composition on the material layer (S2), and forming a hardmask layer by heat-treating the organic film composition. (S3), forming a silicon-containing thin film layer on the hardmask layer (S4), forming a photoresist layer on the silicon-containing thin film layer (S5), and exposing and developing the photoresist layer to form a photoresist pattern Forming (S6), selectively removing the silicon-containing thin film layer and the hardmask layer using the photoresist pattern, and exposing a portion of the material layer (S7), and the exposed portion of the material layer And etching (S8).

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 can be formed, for example, by a chemical vapor deposition method.

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

The step of heat-treating the organic film composition may be performed at, for example, about 100 to 700° C. for about 10 seconds to 1 hour.

The silicon-containing thin film layer may be formed of, for example, a material such as SiCN, SiOC, SiON, SiOCN, SiC, SiO and/or SiN.

In addition, before forming the photoresist layer, a bottom anti-reflective coating (BARC) may be further formed on the silicon-containing thin film layer.

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

The step of etching the exposed portion of the material layer may be performed by dry etching using an etching gas, and the etching gas may be, for example, CHF ₃ , CF ₄ , Cl ₂ , BCl _3, and a mixed gas thereof.

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

The embodiments of the present invention described above 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 the present invention.

Polymer synthesis

Polymerization example One

In a 500 mL 2-neck round-bottomed flask equipped with a condenser, 1-hydroxypyrene 21.8g (0.1mol), 1-naphthol 14.5g (0.1mol), paraformaldehyde 6g (0.2mol), diethyl sulfate 15.4g (0.1mol), Then, 115 g of PGMEA was added, followed by heating at 100° C. for 6 hours to obtain a polymer (MW: 1,500) including a structural unit represented by the following formula (1a).

[Formula 1a]

Crosslinking agent synthesis

Synthesis example One

In an argon atmosphere, diisobutylaluminum (82.5ml, 1M, 82.5mmol) was added dropwise to 3-phenylpropyne (9.55g, 82.2mmol) dissolved in hexane at 25°C by dropping funnel. After stirring for 20 minutes, the temperature was raised to 56° C. and reacted for 4 hours. After cooling and distillation under reduced pressure to remove the solvent, 125 ml of THF was slowly added. Next, CuCl (9.77g, 98.7mmol) was added for 5 minutes to obtain a black result. After stirring for 1 hour, the mixture was added to a mixture of hexane and diluted hydrochloric acid, and the aqueous layer was extracted three times with 150 ml hexane. The obtained organic layer was washed with saturated NaHCO ₃ and then dried over _{Na 2} SO _4. After removing the organic matter, a yellow-green product was obtained, and then recrystallized with hexane to obtain 4.4 g of yellow crystals (Chemical Formula 2a).

[Formula 2a]

Synthesis example 2

After reacting 26 g of 3,5-dimethoxybenzaldehyde and 12 g of succinic acid under acetic aldehyde and PbO, demethylation was performed by dropwise addition of 4-fold ethyl magnesium iodide in an ether solution at 190°C. After quenching by adding ice and ammonium chloride, it is extracted with diethylether. Next, it was washed with distilled water and sodium thiosulfate (Na ₂ S ₂ O ₂ ), extracted with an aqueous sodium carbonate solution, and then separated with a dilute hydrochloric acid solution to obtain a compound represented by the following formula (2b).

[Formula 2b]

Synthesis example 3

The same as in Synthesis Example 2, but by replacing the starting material with p-anisaldehyde, a compound represented by the following formula 2c was obtained.

[Formula 2c]

Synthesis example 4

Ethynyl magnesium bromide (5.5 g in 100 ml THF) dissolved in THF and 24 g of 4-methylbenzyl chloride were stirred in a 2-neck round-bottomed flask equipped with a 250 ml condenser at 50° C. for 5 hours, and distilled under reduced pressure of the solvent for an additional 7 hours. After stirring, an organic layer of 11 g scale was obtained. The organic layer was then added to 11 g of thiourea, 22 ml of water, and 22 ml of ethanol, heated at 100° C. for 1 hour, diluted with water and extracted with diethyl ether to obtain an organic layer again, separated by a column filled with silica gel, and a compound represented by the following formula (2e). Got it.

[Formula 2e]

Comparative Synthesis Example One

After dissolving 3-(4-methoxyphenyl)-1-propanol (1g, 6mmol) and diphenyl disulfide (7.8mmol) in 20 ml of THF in an ice bath, 2.1 ml of tributylphosphine is added dropwise and stirred. After stirring at 0° C. for 5 minutes, reacting at room temperature for 18 hours, diluted in benzene, washed with 5% NaOH aqueous solution and saturated NH ₄ Cl aqueous solution, and the solvent was evaporated. Then, using a column filled with silica gel, 3-(4-methoxyphenyl)propyl phenyl sulfide (1.53g) was obtained. 1.37g (5.34mmol) of the obtained material was dissolved in 25ml dichloroethane, and then cooled to -40℃. To this solution, m-chloroperbenzoic acid (1.37g, 5.61mmol) was added and stirred for 1 hour. The reaction was completed with a saturated Na ₂ SO ₃ aqueous solution, and the organic layer was dried over MgSO ₄ and the solvent was removed. Purified with a silica gel column to obtain 1.41 g of 3-(4-methoxyphenyl)propyl phenyl sulfoxide. N-chlorosuccinimide (5.36 mmol) was added to a solution of this sulfoxide and 25 ml chloroform (1.36 g, 5 mmol), followed by stirring at room temperature for 15 hours. Precipitation was removed with a filter, the solvent of organic matter was removed, the residue was purified with a column, and then recrystallized to obtain 1-chloro-3-(4-methoxyphenyl)propyl phenyl sulfoxide. 0.4ml THF solution was added to 62mg (0.2mmol) of the obtained material, and 0.5ml THF solution of isopropyl magnesium chloride (0.5mmol) was mixed with argon atmosphere at -70°C, followed by stirring for 10 minutes. N-lithiopiperidine was slowly added thereto, and then the temperature was slowly raised to 40° C. (~1 hour), followed by quenching with a saturated aqueous solution of _{NH 4 Cl.} The entire solution was extracted with chloroform, and the organic layer was washed _{again with NH 4 Cl and dried.} After purifying with a column to obtain a compound represented by the following formula (2f).

[Formula 2f]

Hard mask Preparation of the composition

Example One

The polymer obtained in Polymerization Example 1 and the crosslinking agent obtained in Synthesis Example 1 were blended at a ratio of 60:40 (weight ratio), and then dissolved in 100% by weight of propylene glycol monomethyl ether acetate (PGMEA) to prepare a hardmask composition. The total content of the polymer and the crosslinking agent was 10% by weight based on 100% by weight of propylene glycol monomethyl ether acetate (PGMEA).

Example 2

A hardmask composition was prepared in the same manner as in Example 1, except that the crosslinking agent obtained in Synthesis Example 2 was used instead of the crosslinking agent obtained in Synthesis Example 1.

Example 3

A hardmask composition was prepared in the same manner as in Example 1, except that the crosslinking agent obtained in Synthesis Example 3 was used instead of the crosslinking agent obtained in Synthesis Example 1.

Example 4

A hardmask composition was prepared in the same manner as in Example 1, except that the crosslinking agent obtained in Synthesis Example 4 was used instead of the crosslinking agent obtained in Synthesis Example 1.

Comparative example One

A hardmask composition was prepared in the same manner as in Example 1, except that the crosslinking agent obtained in Synthesis Example 1 was not used.

Comparative example 2

A hardmask composition was prepared in the same manner as in Example 1, except that a crosslinking agent represented by the following Formula A (PD1174, TCI) was used instead of the crosslinking agent obtained in Synthesis Example 1.

[Formula A]

Comparative example 3

A hardmask composition was prepared in the same manner as in Example 1, except that the crosslinking agent obtained in Comparative Synthesis Example 1 was used instead of the crosslinking agent obtained in Synthesis Example 1.

Comparative example 4

A hardmask composition was prepared in the same manner as in Example 1, except that 2,4-hexadiene (>90%, isomer mixture, Sigma Aldrich) represented by the following formula 2g was used instead of the crosslinking agent obtained in Synthesis Example 1. .

[Chemical Formula 2g]

Evaluation 1: Corrosion resistance

After spin-on coating the hardmask compositions according to Examples 1 to 4 and Comparative Examples 1 to 4 on a silicon wafer, heat treatment was performed on a hot plate at 240° C. for 30 minutes to form a thin film having a thickness of 4,000 Å.

Then, the thin film was dry for 120 seconds and 60 seconds using _{CF 4} gas (100mT/600W/42CF ₄ /600Ar/15O ₂ ) and N ₂ /O ₂ mixed gas (50mT/300W/10O ₂ /50N _{2 ), respectively.} After etching, the thickness of the thin film was measured again.

From the thickness and etching time of the thin film before and after dry etching, the etch rate (bulk etch rate, BER) was calculated according to Equation 1 below.

[Calculation 1]

(Initial thin film thickness-thin film thickness after etching)/etching time (Å/sec)

The results are shown in Table 1.

CF ₄ bulk etch rate
(Å/sec) N ₂ /O ₂ bulk etch rate
(Å/sec) Example 1 28.5 26.0 Example 2 28.0 25.4 Example 3 28.2 25.5 Example 4 28.2 25.4 Comparative Example 1 27.5 25.0 Comparative Example 2 31.5 28.0 Comparative Example 3 29.7 27.5 Comparative Example 4 32.3 28.3

Referring to Table 1, the thin film formed from the hardmask composition according to Examples 1 to 4 to which a crosslinking agent having a predetermined structure was added is compared with the thin film formed from the hardmask composition according to Comparative Examples 2 to 4, and CF ₄ gas and N It can be seen that the corrosion resistance is relatively excellent for all ₂ /O _{2 mixed gases.} In addition, as compared to the polymer alone (Comparative Example 1), the etch resistance value did not change significantly, so even though the crosslinking agent was included, the aromaticity was well maintained, so that the etch resistance value was good.

Evaluation 2: planarization properties and gap-fill properties

On the silicon wafer, 0.1 mol equivalent of a thermal acid generator represented by the following Formula B was added to the hardmask compositions according to Examples 1 to 4 and Comparative Examples 1 to 4.

[Formula B]

The prepared composition was applied on a silicon pattern wafer (width 20 nm, depth 200 nm, line & space type pattern) and baked at 240° C. for 120 seconds to form a thin film having a thickness of 2,000 Å. After that, the step and gap-fill characteristics were observed using the FE-SEM equipment.

The gap-fill characteristic was determined by the presence or absence of voids by observing the cross section of the pattern with an FE-SEM facility (Hitachi, S-4800), and the planarization characteristic (step measurement) was as shown in FIG. _{The difference (lH 0} -H ₁ l) of the upper film thickness of the dense) portion and the iso portion was observed by cross-sectional observation with FE-SEM.

The results are shown in Table 2.

Gap - Fill characteristics (with or without void) Planarization characteristics (step difference, nm) Example 1 no void 28 Example 2 no void 31 Example 3 no void 27 Example 4 no void 30 Comparative Example 1 Void 77 Comparative Example 2 no void 65 Comparative Example 3 no void 58 Comparative Example 4 no void 40

Referring to Table 2, the thin film formed from the hardmask composition according to Examples 1 to 4 to which a crosslinking agent having a predetermined structure was added is compared with the thin film formed from the hardmask composition according to Comparative Examples 1 to 4, and the planarization characteristics and gap-fill. It can be seen that characteristics can be secured at the same time.

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 by those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It is within the scope of the invention's rights.

Claims (13)

A polymer comprising a structural unit represented by the following formula (1),
A crosslinking agent represented by the following formula (2), and
menstruum
Including
Organic film composition:
[Formula 1]

In Formula 1,
A ¹ is a divalent cyclic group containing at least one substituted or unsubstituted benzene ring,
B ¹ is a divalent organic group,
* Is the point of connection;
[Formula 2]

In Chemical Formula 2,
L is a divalent organic group containing two double bonds or two triple bonds,
X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,
a and b are each independently an integer of 0 to 4. In claim 1,
The crosslinking agent is an organic film composition represented by the following Chemical Formula 3 or 4:
[Formula 3]

[Formula 4]

In Chemical Formulas 3 and 4,
X and Y are each independently a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a combination thereof,
a and b are each independently an integer of 0 to 4,
c to f are each independently an integer of 0 to 5. In paragraph 2,
In Formulas 3 and 4, the sum of a and b is 1 or more. In paragraph 2,
In Formulas 3 and 4, a and b are each independently an integer of 1 to 4 organic film compositions. In paragraph 2,
In Chemical Formula 3, c and d are each independently an integer of 1 to 4, and e and f in Chemical Formula 4 are each independently an integer of 1 to 4. An organic film composition. In claim 1,
In Chemical Formula 1, A ¹ is a divalent cyclic group containing at least two rings in its structure. In claim 1,
In Formula 1, A ¹ is a divalent cyclic group derived from any one of the compounds listed in the following groups 1 and 2, and the divalent cyclic group is an organic film composition wherein at least one hydrogen atom is substituted or unsubstituted:
[Group 1]

[Group 2]

In group 1 above,
M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl,
In group 2 above,
R ⁰ and R ¹ are each independently hydrogen, a hydroxy group, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C6 to C30 aryl group, a C1 to C30 alkoxy group, a halogen atom, a halogen-containing group, or a It is a combination. In claim 1,
In Formula 1, B ¹ is an organic film composition represented by the following Formula 4:
[Formula 4]

In Chemical Formula 4,
m and n are each independently an integer of 0 to 2,
Z is a divalent cyclic group derived from any one selected from the following group 3, and the divalent cyclic group is a group in which at least one hydrogen atom is substituted or unsubstituted,
* Is the point of connection:
[Group 3]

In group 3 above,
M is a substituted or unsubstituted C1 to C5 alkylene group, -O-, -S-, -SO ₂ -, or carbonyl. In claim 1,
The organic film composition containing the polymer and the crosslinking agent in an amount of 40:60 to 80:20 by weight. In claim 1,
An organic film composition further comprising a thermal acid generator. Providing a layer of material over the substrate,
Applying the organic film composition according to any one of claims 1 to 10 on the material layer,
Forming a hard mask layer by heat-treating the organic film composition,
Forming a silicon-containing thin film layer on the hardmask layer,
Forming a photoresist layer on the silicon-containing thin film layer,
Exposing and developing the photoresist layer to form a photoresist pattern,
Selectively removing the silicon-containing thin film layer and the hardmask layer using the photoresist pattern and exposing a portion of the material layer, and
Etching the exposed portion of the material layer
Including
How to form a pattern. In clause 11,
The step of applying the organic film composition is a pattern forming method performed by a spin-on coating method. In clause 11,
Forming a bottom anti-reflective layer (BARC) prior to forming the photoresist layer.

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