KR20190078309A - Resist underlayer composition, and method of forming patterns using the composition - Google Patents

Abstract

The present invention relates to a composition for a resist underlayer film comprising: a polymer including a moiety represented by chemical formula 1 or a moiety represented by chemical formula 2; and a solvent, and a pattern forming method using the resist underlayer film composition. The definition of the chemical formula 1 and the chemical formula 2 are the same as described in the specification. In addition, the composition for the resist underlayer film can improve adhesion with photoresist.

Description

TECHNICAL FIELD [0001] The present invention relates to a composition for a resist underlayer film, and a pattern forming method using the composition.

The present invention relates to a composition for a resist underlayer film and a pattern forming method using the same.

BACKGROUND ART [0002] In recent years, the semiconductor industry has developed into an ultrafine technology having a pattern of a few to a few nanometers in a pattern of a size of several hundred nanometers. Effective lithographic techniques are essential to realize this ultrafine technology.

In the lithographic technique, a photoresist film is coated on a semiconductor substrate such as a silicon wafer, and exposed and developed to form a thin film. An activating radiation such as ultraviolet rays is irradiated thereon through a mask pattern on which a device pattern is drawn, , And etching the substrate using the obtained photoresist pattern as a protective film to form a fine pattern corresponding to the pattern on the substrate surface.

As the ultrafine pattern manufacturing technique is required, short wavelengths such as i-line (365 nm), KrF excimer laser (wavelength 248 nm) and ArF excimer laser (wavelength 193 nm) used for exposure of photoresist are used. Accordingly, in order to solve problems caused by irregular reflection or standing waves from the semiconductor substrate of the activation radiation, many studies have been made to solve the problem through a resist underlayer having an optimum reflectance between the resist and the semiconductor substrate have

Meanwhile, a method of using a high energy beam such as EUV (extreme ultraviolet (wavelength 13.5 nm) or E-beam (electron beam)) as a light source for manufacturing fine patterns in addition to the activation radiation is also performed. In the case of the light source, Although there is no reflection, research to improve the adhesion between the resist and the underlying film to improve the collapse of the pattern formed by pattern refinement has been extensively investigated. In addition, studies for reducing the problems caused by the light source as described above, as well as studies for improving etch selectivity and chemical resistance have been widely studied.

In addition, in addition to the investigation for reducing the problems caused by the light source as described above, attempts have also been made to improve etch selectivity, chemical resistance, and adhesion to a resist.

One embodiment provides a composition for a resist underlayer film which can improve coating uniformity even when the thickness is reduced, reduce the occurrence of surface roughness, and improve adhesion to a photoresist.

Another embodiment provides a pattern formation method using the composition for a resist underlayer film.

According to one embodiment, there is provided a composition for a resist underlayer film comprising a polymer comprising a moiety represented by the following formula (1) or a moiety represented by the following formula (2), and a solvent.

[Chemical Formula 1]

A represents a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C2 to C10 heterocycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group , A substituted or unsubstituted C2 to C30 heteroarylene group, or a combination thereof,

R ² is any one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,

L ³ to L ⁶ each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ² and X ³ are each independently a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

d to i each independently represents an integer of 0 to 10,

* Is the connection point,

(2)

In Formula 2,

A is a substituted C1 to C20 alkylene group, a substituted C3 to C10 cycloalkylene group, a substituted C2 to C10 heterocycloalkylene group, a substituted C6 to C30 arylene group, a substituted C2 to C30 heteroarylene group, , Wherein the substituent of A includes at least one of a C5 to C30 alkyl group, a C3 to C30 cycloalkyl group, and a C6 to C30 aryl group,

L ⁹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ⁵ and X ⁶ each independently represent a single bond, -O-, -S-, -S (= O) -, -S (= O) 2 -, -C (= O) -, substituted or unsubstituted A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

m to r each independently represents an integer of 0 to 10,

* Is the connection point.

According to another embodiment, there is provided a method of manufacturing a semiconductor device, comprising: forming a film to be etched on a substrate; forming a resist underlayer film by applying a composition for a resist underlayer film according to an embodiment on the film to be etched; And etching the photoresist pattern sequentially with the resist underlayer film and the etching target film using an etching mask.

The composition for a resist underlayer film according to one embodiment can provide a resist underlayer film which can improve the coating uniformity and reduce the possibility of occurrence of defects.

1 to 5 are sectional views for explaining a pattern forming method using a composition for a resist underlayer film according to an embodiment.

Hereinafter, exemplary embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the drawings, the thicknesses are enlarged to clearly show the layers and regions, and like parts are denoted by the same reference numerals throughout the specification. Whenever a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle.

Unless otherwise defined herein, "substituted" means that the hydrogen atom in the compound is a halogen atom (F, Br, Cl, or I), a hydroxy group, an alkoxy group, a nitro group, a cyano group, an amino group, An ester group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a vinyl group, a C1 to C20 alkyl group, a C2 to C20 alkene group, a cyano group, C6 to C30 arylalkyl groups, C6 to C30 aryl groups, C1 to C30 alkoxy groups, C1 to C20 heteroalkyl groups, C3 to C20 heteroarylalkyl groups, C3 to C30 cycloalkyl groups , A C3 to C15 cycloalkenyl group, a C6 to C15 cycloalkynyl group, a C3 to C30 heterocycloalkyl group, and combinations thereof.

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

Also, unless otherwise defined herein, '*' refers to the point of attachment of a compound or moiety.

Hereinafter, the composition for a resist underlayer film according to one embodiment will be described.

The composition for a resist underlayer film according to an embodiment includes a polymer comprising a moiety represented by the following formula (1) or a moiety represented by the following formula (2), and a solvent.

[Chemical Formula 1]

A represents a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C2 to C10 heterocycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group , A substituted or unsubstituted C2 to C30 heteroarylene group, or a combination thereof,

R ² is any one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,

L ³ to L ⁶ each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ² and X ³ are each independently a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

d to i each independently represents an integer of 0 to 10,

* Is the connection point,

(2)

In Formula 2,

A is a substituted C1 to C20 alkylene group, a substituted C3 to C10 cycloalkylene group, a substituted C2 to C10 heterocycloalkylene group, a substituted C6 to C30 arylene group, a substituted C2 to C30 heteroarylene group, , Wherein the substituent of A includes at least one of a C5 to C30 alkyl group, a C3 to C30 cycloalkyl group, and a C6 to C30 aryl group,

L ⁹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ⁵ and X ⁶ each independently represent a single bond, -O-, -S-, -S (= O) -, -S (= O) 2 -, -C (= O) -, substituted or unsubstituted A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

m to r each independently represents an integer of 0 to 10,

* Is the connection point.

For example, in Formula 1,

A may be a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof.

In another embodiment, in Formula 1,

X ² and X ³ are each independently a single bond, -O-, or -S-,

L ³ and L ⁵ are each independently a substituted or unsubstituted C6 to C30 arylene group,

L ⁴ and L ⁶ may each independently be a single bond, a substituted or unsubstituted C1 to C20 alkylene group.

For example, X ² and X ^{3 in} Formula 1 and X ⁵ and X ⁶ in Formula 2 may be independently represented by Formula 3 below.

(3)

In Formula 3,

R ^a to R ^c each independently represent a substituted or unsubstituted C1 to C5 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ^a and X ^b are each independently -O- or -S-,

each of na to ne is independently an integer of 0 to 5,

Means that a hydrogen atom is substituted with a C1 to C5 alkyl group, a hydroxyl group, or a thiol group.

As another example, the above-mentioned Formula 1 and Formula 2 may be represented by the following Formulas 1-1 and 2-1, respectively.

[Formula 1-1]

In Formula 1,

R ¹ is any ^one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,

R ² is hydrogen, deuterium, -F (fluoro group), -Cl (chloro group), -Br (bromo group), -I (iodo group), hydroxyl group, cyano group, nitro group, 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 alkoxy group, a substituted or unsubstituted C2 to C30 alkenyl group, A substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 heterocycloalkyl group, a substituted or unsubstituted C6 to C30 aryl A substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C6 to C30 arylthio group, or a combination thereof,

L ¹ to L ⁶ each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ¹ to X ³ each independently represent a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

a to i are each independently an integer of 0 to 10,

* Is the connection point,

[Formula 2-1]

R ³ is any one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,

L ⁷ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ⁴ to X ⁶ each independently represent a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,

j to r each independently represent an integer of 0 to 10,

* Is the connection point.

The moiety represented by the above formula (1) or (2) has a cyanuric acid skeleton at its center. With this structure, it is possible to have a relatively high refractive index (n) and a low extinction coefficient (k) with respect to the light transmitted from the light source used in the photoresist.

Specifically, when the moiety represented by the formula (1) or (2) has a cyanuric acid skeleton at its center, the activation radiation i-line (365 nm), the KrF excimer laser (wavelength: 248 nm), the ArF excimer laser And can have a high refractive index and a low extinction coefficient for light having a high energy wavelength such as EUV (extreme ultraviolet (wavelength 13.5 nm), E-Beam (electron beam), etc.) as well as light having a short wavelength.

Thus, when a composition containing the above-mentioned moiety-containing polymer is used as a material for a photoresist lower layer film, for example, the light interference effect can be suppressed as having a reflectance optimized for the light source from the cornea film, It can have a high etch selectivity with the photoresist layer in the etching process, and can have excellent flatness.

The polymer comprising the moiety according to Formula 1 or the moiety according to Formula 2 may include at least one sulfur (S) in the main chain. Polymers containing at least one sulfur atom in the main chain can have a high refractive index implementation and a fast etch rate.

According to one embodiment, R ¹ of Formula 1 is an alkyl group of C5 to C30,

R ² is selected from the group consisting of hydrogen, deuterium, -F, -Cl, a hydroxyl group, a cyano group, a nitro group, an amino group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, Lt; / RTI >

At least one of X ¹ to X ³ is independently -O- or -S-,

L ¹ to L ⁶ are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group,

a to i may each independently be an integer of 0 to 5;

For example, R ¹ in formula (1) may be a C5 to C30 long chain alkyl group. According to this, in the polymer having a high molecular weight, since the substituent substituted in the central skeleton of the formula (1) is hydrophobic, the solubility in a solvent can be excellent, and thus the coating property and the adhesion property to the photoresist can be improved .

Likewise, according to one embodiment, R ³ of Formula 2 is a C 5 to C 30 alkyl group,

At least one of X ⁴ to X ⁶ is independently -O- or -S-,

L ⁷ to L ¹² are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group,

Each of j to r may independently be an integer of 0 to 5.

Similarly to Formula (1), R ³ may also be a long-chain alkyl group of C 5 to C 30. Also, since the substituent substituted in the central skeleton of formula (2) is hydrophobic, even when a polymer having a high molecular weight is formed, solubility in a solvent can be excellent, and coating and adhesiveness to a photoresist can be improved have.

Specifically, the polymer can form a resist underlayer film having excellent solubility and excellent coating uniformity. When the polymer is used as a material for a resist underlayer film, the formation of pinholes and voids in the baking process and the thickness It is possible not only to form a uniform thin film without deterioration of scattering but also to provide excellent gap-fill and planarization characteristics when a step is present in a lower substrate or a film, or when a pattern is formed.

In one embodiment, R ¹ in Formula 1 may be a C5 to C30 chain alkyl group,

R ² is selected from the group consisting of hydrogen, -F, -Cl, a hydroxyl group, a cyano group, a nitro group, an amino group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, or a substituted or unsubstituted C3- Lt; / RTI >

At least one of X ¹ to X ³ may be -S-,

L ¹ to L ⁶ are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group,

a to i may each independently be an integer of 0 to 5,

R ³ in Formula 2 may be a C5 to C30 chain alkyl group,

At least one of X ⁴ to X ⁶ may be -S-,

L ⁷ to L ¹² each independently may be a single bond or a substituted or unsubstituted C1 to C20 alkylene group,

Each of j to r may independently be an integer of 0 to 5.

As described above, each of the moieties according to Formula 1 or Formula 2 has a cyanuric acid skeleton at its center and can have a relatively high refractive index and a low extinction coefficient. Therefore, when the composition containing the polymer is used as a material for a lower layer film of a photoresist, for example, it is possible to suppress the optical interference effect as having a reflectance optimized for the light source from the flattening film, Can have a high etch selectivity, and can have excellent flatness.

In addition, polymers comprising a moiety according to formula (I) or a moiety according to formula (II) contain sulfur (S) in the main chain and can have a high refractive index and a high etch rate.

In one embodiment, the polymer may comprise a first moiety represented by Formula 1 or Formula 2, and a second moiety represented by Formula 2 and including A different from the first moiety. have.

In one embodiment, the second moiety is a moiety of formula (2)

A comprises a substituent selected from the group consisting of a substituted C1 to C20 alkylene group, a substituted C3 to C10 cycloalkylene group, a substituted C2 to C10 heterocycloalkylene group, a substituted C6 to C30 arylene group , A substituted C2 to C30 heteroarylene group, or a combination thereof, wherein the substituent of A includes at least one of a C5 to C30 alkyl group, a C3 to C30 cycloalkyl group, and a C6 to C30 aryl group,

L ⁹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,

X ⁵ and X ⁶ are each independently -O- or -S-,

Each of m to r may independently be an integer of 0 to 5.

For example, when the polymer comprises different first moieties and second moieties, the first moiety and the second moiety are selected from the group consisting of X ² and X ³ represented by Formula 3 and X ⁵ and X < ⁶ > may be further different from each other.

Alternatively, the polymer may further include a third moiety represented by Formula 2 and including A different from the first moiety and the second moiety.

More specifically, the polymer may comprise at least one of the moieties represented by the following formulas (4) to (7).

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

The polymer may have a weight average molecular weight of 1,000 to 100,000. Specifically, it may have a weight average molecular weight of 1,000 to 50,000, more specifically 1,000 to 20,000. By having the weight average molecular weight in the above range, it is possible to optimize by adjusting the carbon content of the resist underlayer film composition containing the polymer and the solubility in the solvent.

The polymer may be contained in an amount of 0.1 to 50% by weight, 0.1 to 30% by weight, or 0.1 to 15% by weight based on the total amount of the composition for a resist underlayer film. By being included in the above range, the thickness, surface roughness and planarization degree of the resist underlayer film can be controlled.

In addition, the composition for a resist underlayer film may further include a crosslinking agent.

Examples of the cross-linking agent include melamine-based, substitution-based, or polymer-based ones. Preferably, the crosslinking agent having at least two crosslinking substituents is, for example, a methoxymethylated glycerol, a butoxymethylated glyceryl, a methoxymethylated melamine, a butoxymethylated melamine, a methoxymethylated benzoguanamine, a butoxy Methylated benzoguanamine, methoxymethylated urea, butoxymethylated urea, methoxymethylated thiourea, or butoxymethylated thiourea can be used.

As the crosslinking agent, a crosslinking agent having high heat resistance can be used. For example, a compound containing a crosslinking forming substituent group having an aromatic ring (for example, a benzene ring or a naphthalene ring) in the molecule can be used. The crosslinking agent may have, for example, two or more crosslinking sites.

In addition, the composition for a resist underlayer film may contain an acrylic resin, an epoxy resin, a novolak resin, a glucuril resin, and a melamine resin in addition to the moiety represented by Formula 1 or the moiety represented by Formula 2 But may also include, but is not limited to, one or more other polymers in the resin.

The composition for a resist underlayer film may further comprise additives such as a surfactant, a thermal acid generator, a plasticizer, or a combination thereof.

The surfactant may be, for example, an alkylbenzenesulfonate, an alkylpyridinium salt, a polyethylene glycol, or a quaternary ammonium salt, but is not limited thereto.

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

The additive may be included in an amount of 0.001 to 40 parts by weight based on 100 parts by weight of the composition for a resist underlayer film. Within the above range, the solubility can be improved without changing the optical properties of the composition for a resist underlayer film.

The solvent is not particularly limited as long as it has sufficient solubility or dispersibility in the polymer. Examples of the solvent include propylene glycol, propylene glycol diacetate, methoxypropanediol, diethylene glycol, diethylene glycol butyl ether, tri (ethylene glycol) But are not limited to, methyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, cyclohexanone, ethyl lactate, gamma-butyrolactone, N, N-dimethylformamide, , Methyl pyrrolidinone, acetylacetone, and ethyl 3-ethoxypropionate.

As described above, since the polymer according to one embodiment has improved solubility and is stable to an organic solvent, when a composition for a resist underlayer film containing the polymer is used, for example, as a photoresist lower layer film material, It is possible to minimize the occurrence of byproducts such as peeling off by a solvent or generation of a chemical during the process for forming a photoresist and minimizing the thickness loss due to the upper photoresist solvent.

Since the composition for a resist underlayer film according to an embodiment has excellent coating uniformity, excellent stability, high refractive index can be realized, and an etching rate is also fast, a high energy ray such as EUV (Extreme Ultraviolet) or Beam Can be applied to a lithography process. The lithography process using a high-energy line is a lithography technique using EUV light having a very short wavelength of 10 nm to 20 nm, for example, 13.5 nm, or using light corresponding to an electron beam region. An ultrafine pattern having a width of 20 nm or less .

In the case of a patterning process for forming an ultrafine pattern using a high-energy line such as EUV or E-Beam, not only a reflection problem from the substrate but also a collapse of the pattern due to the miniaturization of the pattern, roughness of the side wall of the photoresist pattern, ). ≪ / RTI >

When a lower layer film is formed by a composition for a resist underlayer film containing a polymer according to an embodiment, the solubility in a solvent is excellent, coating uniformity is improved, and surface roughness can be minimized. In addition, since the lower layer film formed by the composition for a lower layer film according to one embodiment has a reflectance optimized for the light source from the flattening film, the light interference effect can be suppressed and the flatness is improved, Can be prevented.

On the other hand, according to another embodiment, there is provided a resist underlayer film produced using the composition for a resist underlayer film as described above. The resist underlayer film may be formed by coating the composition for a resist underlayer film, for example, on a substrate, and then curing the resist underlayer film through a heat treatment process. The resist underlayer film may be, for example, an antireflection film.

Hereinafter, a method of forming a pattern using the composition for a resist underlayer film will be described with reference to Figs. 1 to 5. Fig.

1 to 5 are sectional views for explaining a pattern forming method using a composition for a resist underlayer film according to the present invention.

Referring to FIG. 1, an object to be etched is first prepared. The etching target may be a thin film 102 formed on the semiconductor substrate 100. Hereinafter, only the case where the object to be etched is the thin film 102 will be described. The thin film surface is pre-cleaned to remove contaminants or the like remaining on the thin film 102. [ The thin film 102 may be, for example, a silicon nitride film, a polysilicon film, or a silicon oxide film.

Next, on the surface of the cleaned thin film 102, a composition for a resist underlayer film including a polymer having a moiety represented by the formula (1) or a moiety represented by the formula (2) and a solvent is coated by a spin coating method.

Thereafter, the resist underlayer film 104 is formed on the thin film by performing a drying and baking process. The baking treatment may be carried out at 100 to 500, for example, at 100 to 300. More specifically, the description of the composition for a resist underlayer film is omitted in order to avoid duplication because it has been described in detail above.

Referring to FIG. 2, a photoresist film is coated on the resist lower layer film 104 to form a photoresist film 106.

Examples of the photoresist include a positive type photoresist containing a naphthoquinone diazide compound and a novolac resin, an acid generator capable of dissociating by exposure to light, an acid generator decomposing in the presence of an acid to increase the solubility in an alkali aqueous solution, A chemical amplification type photoresist containing an alkali-soluble resin, a chemical amplification type photoresist containing an alkali-soluble resin having a group capable of decomposing in the presence of an acid and capable of imparting a resin capable of increasing solubility in an aqueous alkali solution Type photoresist.

Next, a first baking process for heating the substrate 100 on which the photoresist film 106 is formed is performed. The first baking process may be performed at a temperature of 90-120.

Referring to FIG. 3, the photoresist film 106 is selectively exposed.

An exposure process for exposing the photoresist film 106 is described as an example. An exposure mask having a predetermined pattern formed on a mask stage of an exposure apparatus is placed, and the exposure mask 110). Then, by irradiating the mask 110 with light, a predetermined portion of the photoresist film 106 formed on the substrate 100 selectively reacts with the light transmitted through the exposure mask.

Examples of the light that can be used in the exposure process include not only light having a short wavelength such as an activating radiation line i-line (365 nm), a KrF excimer laser (wavelength 248 nm), and an ArF excimer laser (wavelength 193 nm) ultraviolet (wavelength: 13.5 nm), and E-beam (electron beam).

The exposed portion of the photoresist film 106b is relatively hydrophilic compared to the non-exposed portion of the photoresist film 106a. Therefore, the photoresist films of the exposed region 106b and the non-exposed region 106a have different solubilities.

Next, a second baking process is performed on the substrate 100. The second baking process may be performed at a temperature of 90-150. By performing the second baking process, the photoresist film corresponding to the exposed region becomes a state that is easily dissolved in a specific solvent.

Referring to FIG. 4, a photoresist pattern 106 is formed by dissolving and removing a photoresist film 106b corresponding to the exposed region using a developing solution. Specifically, the photoresist pattern corresponding to the exposed region is dissolved and removed using a developer such as tetra-methyl ammonium hydroxide (TMAH) to complete the photoresist pattern 108.

Subsequently, the resist underlayer film is etched using the photoresist pattern 108 as an etching mask. The organic film pattern 112 is formed by the above-described etching process. The etching may be performed by, for example, 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. As described above, since the resist underlayer film formed by the resist underlayer film composition according to one embodiment has a high etching rate, a smooth etch process can be performed in a short time.

Referring to FIG. 5, the exposed thin film 102 is etched by applying the photoresist pattern 108 as an etching mask. As a result, the thin film is formed into the thin film pattern 114. In the above-described exposure process, the thin film pattern 114 formed by the exposure process performed using the ArF light source may have a width of several tens nm to several hundreds of nm, and may be a thin film formed by an exposure process performed using an EUV light source The pattern 114 may have a width of 20 nm or less.

Hereinafter, the present invention will be described in more detail with reference to examples relating to the synthesis of the polymer and the production of a composition for a resist underlayer film including the same. However, the present invention is not limited by the following examples.

Synthetic example

Synthesis Example 1

Diallyl-5- (2-hydroxyethyl) -isocyanurate (6.33 g, 0.025 mol), 1,3-diallyl-5-pentyl-isocyanurate (6.98 g, 0.025 mol), 1 , 30 g of N, N-dimethylformamide (DMF), and the mixture was heated to 80 ° C with stirring using a magnetic bar. The polymerization reaction proceeded. After reacting for 4 hours, 1-mercaptohexane (2.96.025 mol) and AIBN (0.33 g, 0.002 mol) were added and further reaction was carried out for 2 hours to produce a polymerization reaction product containing the structural unit of formula (7). After completion of the reaction, the temperature was lowered to room temperature (23 ° C to 25 ° C), diluted with 80 g of tetrahydrofuran (THF), and purified four times using toluene and IPA (Isopropyl alcohol) to remove low molecular weight and catalyst, (Molecular weight (Mw) = 8,000) containing the structural unit of the formula (4) was obtained.

[Chemical Formula 4]

Synthesis Example 2

(12.7g, 0.05mol), Biphenyl-4,4'-dithiol (8.73g, 0.04mol) and AIBN (0.66g, 0.04mol) were added to a 250mL round- , 0.004 mol) and DMF (57 g) were charged, and the mixture was heated with stirring using a magnetic bar, and polymerization was carried out at 80 ° C. After reacting for 8 hours, 1-mercaptohexane (2.96.025 mol) and AIBN (0.33 g, 0.002 mol) were added and further reaction was carried out for 3 hours to produce a polymerization reaction product containing the structural unit of formula (8). After the completion of the reaction, the temperature was lowered to room temperature (23 ° C to 25 ° C), diluted with 80 g of THF, and purified four times using toluene and IPA (Isopropyl alcohol) to remove low molecular weight and catalyst, (Molecular weight (Mw) = 3,500) was obtained.

[Chemical Formula 5]

Synthetic example  3

1,3-diallyl-5-methyl-isocyanurate (11.2 g, 0.05 mol), 1,4-Dithioerythritol (6.17 g, 0.04 mol), AIBN (0.66 g, 0.004 mol) and DMF (30 g) were added to a 100 mL round- And the mixture was heated with stirring using a magnetic bar, and polymerization was carried out at 80 ° C. After reacting for 4 hours, 1-mercaptohexane (2.96.025 mol) and AIBN (0.33 g, 0.002 mol) were added and further reaction was carried out for 2 hours to produce a polymerization reaction product containing the structural unit of formula (9). After completion of the reaction, the temperature was lowered to room temperature (23 ° C to 25 ° C), diluted with 80 g of THF, and purified four times using toluene and IPA (Isopropyl alcohol) to remove low molecular weight and catalyst, (Molecular weight (Mw) = 7,000) was obtained.

[Chemical Formula 6]

Synthesis Example 4

Bisphenol A diallyl ether (15.4 g, 0.05 mol), 1,4-Dithioerythritol (6.17 g, 0.04 mol), AIBN (0.66 g, 0.004 mol) and 56 g of DMF were placed in a 250 mL round-bottomed flask equipped with a condenser, The temperature was raised with stirring, and the polymerization reaction was carried out at 80 ° C. After reacting for 4 hours, 1-mercaptobutane (2.25.025 mol) and AIBN (0.33 g, 0.002 mol) were added, and the mixture was further reacted for 2 hours to produce a polymerization reaction containing the structural unit of formula (10). After completion of the reaction, the temperature was lowered to room temperature (23 ° C to 25 ° C), diluted with 80 g of THF, and purified four times using toluene and IPA (Isopropyl alcohol) to remove low molecular weight and catalyst, (Molecular weight (Mw) = 6,500) was obtained.

(7)

Comparative Synthetic Example

Methyl methacrylate (40 g), 2-hydroxyacrylate (52.1 g), benzyl acrylate (70.4 g), AIBN (2 g) and Dioxane (306 g) were charged into a 500 ml two-neck round flask and the condenser was connected. The temperature was raised to 80 ° C, and after 2.5 hours of reaction, the reaction solution was cooled to room temperature. The reaction solution was transferred to a 3 L light bottle and washed with hexane. The obtained resin was dried in a vacuum oven at 30 캜 to remove residual solvent to finally obtain a polymer (Mw = 12,000) containing a moiety represented by the following formula (12).

[Chemical Formula 12]

Preparation of Composition for Resist Underlayer Film

Example 1

The polymer prepared in Synthesis Example 1 and Pyridinium p-toluenesulfonate (1 part by weight based on 100 parts by weight of the polymer) were dissolved in a mixed solvent of propylene glycol monomethyl ether and ethyl lactate (mixing weight ratio = 1: 1) Followed by stirring to prepare a composition for a resist underlayer film.

The mixed solvent was used in an amount of 1 wt% based on the total composition of the composition for a resist underlayer film in which the solid content of the polymer was prepared.

Example 2

The procedure of Example 1 was repeated except that the polymer of Synthesis Example 2 was used.

Example 3

The procedure of Example 1 was repeated except that the polymer of Synthesis Example 3 was used.

Example 4

The procedure of Example 1 was repeated except that the polymer of Synthesis Example 4 was used.

Comparative Example 1

The procedure of Example 1 was repeated, except that the polymer of Comparative Synthesis Example 1 was used.

evaluation

Evaluation 1: Coating uniformity

2 ml of each of the compositions prepared in Examples 1 to 4 and Comparative Example 1 were applied onto 8-inch wafers, respectively, and then spin-coated with an auto track (TEL ACT-8) at a main spin speed of 1,500 rpm for 20 seconds Followed by curing at 210 DEG C for 90 seconds to form a 300 nm thick thin film. The coating uniformity was measured by measuring the thickness of 51 points on the horizontal axis, and the results are shown in Table 1 below.

The smaller the coating uniformity (%) value, the better the coating uniformity.

Coating uniformity (%) Example 1 1.5 Example 2 2.1 Example 3 1.9 Example 4 1.8 Comparative Example 1 3.3

Evaluation 2: Contact angle

2 ml of each of the compositions prepared in Examples 1 to 4 and Comparative Example 1 was applied to each of the 4-inch wafers, followed by spin coating at 1,500 rpm for 20 seconds using a spin coater (Mikasa). Thereafter, the film was cured at 210 DEG C for 90 seconds to form a thin film, and then the contact angle was measured when distilled water (DIW) was dropped on the surface. The measured contact angles are as shown in Table 2 below.

The larger the contact angle, the better the adhesion to the resist.

Contact angle (°) Example 1 72 Example 2 69 Example 3 69 Example 4 68 Comparative Example 1 62

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious to those who have. Accordingly, it should be understood that such modifications or alterations should not be understood individually from the technical spirit and viewpoint of the present invention, and that modified embodiments fall within the scope of the claims of the present invention.

100: substrate 102: thin film
104: resist lower layer film 106: photoresist film
108: photoresist pattern 110: mask
112: organic film pattern 114: thin film pattern

Claims (17)

A polymer comprising a moiety represented by the following formula (1) or a moiety represented by the following formula (2); And a solvent:
[Chemical Formula 1]

A represents a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C2 to C10 heterocycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group , A substituted or unsubstituted C2 to C30 heteroarylene group, or a combination thereof,
R ² is any one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,
L ³ to L ⁶ each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,
X ² and X ³ are each independently a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,
d to i each independently represents an integer of 0 to 10,
* Is the connection point,
(2)

In Formula 2,
A is a substituted C1 to C20 alkylene group, a substituted C3 to C10 cycloalkylene group, a substituted C2 to C10 heterocycloalkylene group, a substituted C6 to C30 arylene group, a substituted C2 to C30 heteroarylene group, , Wherein the substituent of A includes at least one of a C5 to C30 alkyl group, a C3 to C30 cycloalkyl group, and a C6 to C30 aryl group,
L ⁹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,
X ⁵ and X ⁶ each independently represent a single bond, -O-, -S-, -S (= O) -, -S (= O) 2 -, -C (= O) -, substituted or unsubstituted A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,
m to r each independently represents an integer of 0 to 10,
* Is the connection point. The method of claim 1,
In Formula 1,
A is a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof. The method of claim 1,
In Formula 1,
X ² and X ³ are each independently a single bond, -O-, -S-,
L ³ and L ⁵ are each independently a substituted or unsubstituted C6 to C30 arylene group,
L ⁴ and L ⁶ are each independently a single bond, or a substituted or unsubstituted C1 to C20 alkylene group. The method of claim 1,
Wherein the formula (1) and the formula (2) are represented by the following formulas (1-1) and (2-1)
[Formula 1-1]

[Formula 2-1]

In the above Chemical Formulas 1 and 2,
R ¹ is selected from the group consisting of hydrogen, deuterium, -F (fluoro), -Cl (chloro), -Br (bromo), -I (iodo), hydroxyl, cyano, nitro, 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 alkoxy group, a substituted or unsubstituted C2 to C30 alkenyl group, A substituted or unsubstituted C1 to C10 alkoxy group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 heterocycloalkyl group, a substituted or unsubstituted C6 to C30 aryl A substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C6 to C30 arylthio group, or a combination thereof,
R ² and R ³ are each independently any one of a C 5 to C 30 alkyl group, a C 3 to C 30 cycloalkyl group, and a C 6 to C 30 aryl group,
L ¹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,
X ¹ to X ⁶ each independently represents a single bond, -O-, -S-, -S (= O) -, -S (= O) _2- , -C A substituted or unsubstituted C2 to C10 alkenylene group, a substituted or unsubstituted C2 to C10 alkynylene group, a substituted or unsubstituted C3 to C10 cycloalkylene group, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C2 to C10 alkenylene group, Substituted C2 to C10 heterocycloalkylene groups, substituted or unsubstituted C6 to C30 arylene groups, or combinations thereof,
a to r each independently represents an integer of 0 to 10,
* Is the connection point. 5. The method of claim 4,
In Formula 1-1,
R ¹ is selected from the group consisting of hydrogen, deuterium, -F, -Cl, a hydroxyl group, a cyano group, a nitro group, an amino group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, Lt; / RTI >
R ² in the above formula (1) is a C 5 to C 30 alkyl group,
At least one of X ¹ to X ³ is independently -O- or -S-,
L ¹ to L ⁶ are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group,
and each of a to i is independently an integer of 0 to 5. 5. The method of claim 4,
R ³ in the above formula (2-1) is a C 5 to C 30 alkyl group,
At least one of X ⁴ to X ⁶ is independently -O- or -S-,
L ⁷ to L ¹² are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group,
and each of j to r is independently any one of 0 to 5. The method of claim 1,
A composition for a resist underlayer film comprising a first moiety represented by Formula 1 or Formula 2 and a second moiety represented by Formula 2 and comprising A different from the first moiety. 8. The method of claim 7,
Wherein the second moiety is represented by Formula 2,
A is a substituted C1 to C20 alkylene group, a substituted C3 to C10 cycloalkylene group, a substituted C2 to C10 heterocycloalkylene group, a substituted C6 to C30 arylene group, a substituted C2 to C30 heteroarylene group, , Wherein the substituent of A includes at least one of a C5 to C30 alkyl group, a C3 to C30 cycloalkyl group, and a C6 to C30 aryl group,
L ⁹ to L ¹² each independently represent a single bond, a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,
X ⁵ and X ⁶ are each independently -O- or -S-,
and m to r each independently represent any one of 0 to 5. The method of claim 1,
X ² and X ^{3 in} the formula 1 and X ⁵ and X ⁶ in the formula 2 independently represent a composition for a resist underlayer film represented by the following formula 3:
(3)

In Formula 3,
R ^a to R ^c each independently represent a substituted or unsubstituted C1 to C5 alkylene group, a substituted or unsubstituted C6 to C30 arylene group, or a combination thereof,
X ^a and X ^b are each independently -O- or -S-,
each of na to ne is independently an integer of 0 to 5,
Means that a hydrogen atom is substituted with a C1 to C5 alkyl group, a hydroxyl group, or a thiol group. The method according to claim 1,
Wherein the polymer comprises at least one of the moieties represented by the following formulas (4) to (7):
[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

. The method according to claim 1,
Wherein the polymer has a weight average molecular weight of 1,000 to 100,000. The method according to claim 1,
Wherein the polymer is contained in an amount of 0.1 to 50% by weight based on the total amount of the composition. The method according to claim 1,
Wherein the composition further comprises a crosslinking agent having two or more crosslinking sites. The method according to claim 1,
Wherein the composition further comprises an additive for a surfactant, a thermal acid generator, a plasticizer, or a combination thereof. Forming a film to be etched on the substrate,
Applying a resist underlayer film composition according to any one of claims 1 to 14 on the etch target film to form a resist underlayer film,
Forming a photoresist pattern on the resist lower layer film, and
And sequentially etching the resist lower layer film and the etching target film using the photoresist pattern as an etching mask. 16. The method of claim 15,
The step of forming the photoresist pattern
Forming a photoresist film on the resist lower layer film,
Exposing the photoresist film, and
And developing the photoresist film. 16. The method of claim 15,
Wherein the step of forming the resist underlayer film further comprises a heat treatment at a temperature of 100 to 500 after coating the composition for a resist underlayer film.

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