KR20240040480A - Semiconductor photoresist composition and method of forming patterns using the composition - Google Patents

Abstract

An acrylic polymer containing a structural unit represented by Formula 1; A compound represented by Formula 2; photoacid generator (PAG); and a composition for semiconductor photoresist containing a solvent, and a method of forming a pattern using the same.
Specific details of Formulas 1 and 2 are the same as defined in the specification.

Description

Composition for semiconductor photoresist and method of forming a pattern using the same {SEMICONDUCTOR PHOTORESIST COMPOSITION AND METHOD OF FORMING PATTERNS USING THE COMPOSITION}

This disclosure relates to a composition for semiconductor photoresist and a method of forming a pattern using the same.

In photolithography technology, for example, a resist film made of a resist composition is formed on a substrate, and the resist film is selectively exposed to radiation such as light or electron beam through a photomask on which a predetermined pattern is formed, By performing development, a process of forming a resist pattern of a predetermined shape on the resist film is performed. A resist composition in which the exposed portion changes to a property that dissolves in the developer is called a positive type, and a resist composition that changes the exposed portion in a property that does not dissolve in the developer is called a negative type.

Recently, in the manufacture of semiconductor devices and liquid crystal display devices, miniaturization is rapidly progressing due to advances in lithography technology. As a means of miniaturization, shortening the wavelength of exposure light is generally being implemented. Specifically, ultraviolet rays represented by g-rays and i-rays were used in the past, but currently, KrF excimer laser (248 nm) has been introduced, and in addition, ArF excimer laser. (193㎚) is starting to be introduced. In addition, shorter wavelength F ₂ excimer laser (157 nm), EUV (extreme ultraviolet light), electron beam, X-ray, etc. are also being examined.

Additionally, in order to reproduce patterns with fine dimensions, a resist material with high resolution is required. As such a resist material, a chemically amplified resist composition is used that contains a base resin whose physical and chemical properties change with a catalytic amount of acid, an acid generator that generates acid upon exposure, some additives, and a solvent that dissolves them. For example, in the case of a positive chemically amplified resist, if acid is generated from an acid generator by exposure during resist pattern formation, the exposed portion becomes alkali soluble.

In particular, because light absorption is high at deep ultraviolet rays or KrF excimer laser wavelengths, chemically amplified photoresists using polyhydroxystyrene derivatives with relatively lower absorption as a base resin are being widely studied.

One embodiment provides a composition for semiconductor photoresist that can obtain a high-resolution resist pattern.

Another embodiment provides a method of forming a pattern using the composition for semiconductor photoresist.

A composition for a semiconductor photoresist according to one embodiment includes an acrylic polymer containing a structural unit represented by the following Chemical Formula 1; A compound represented by the following formula (2); photoacid generator (PAG); and solvents.

[Formula 1]

[Formula 2]

In Formula 1 and Formula 2,

R ^a is hydrogen or a methyl group,

R ¹ is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkoxycarbonyl group, or a halogen group,

R ² to R ⁵ are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C3 to C20 alkenyl group. C20 cycloalkyl group, substituted or unsubstituted C3 to C20 cycloalkenyl group, substituted or unsubstituted C3 to C20 cycloalkynyl group, substituted or unsubstituted C6 to C20 aryl group, substituted or unsubstituted C2 to C20 heteroaryl group. or a combination thereof,

m1 is one of the integers from 1 to 4,

n1 and n2 are each independently integers of 1 or 2.

R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C6 to C20 aryl group thereof. It can be a combination.

R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or any of these. It can be a combination.

R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C10 alkyl group, a substituted or unsubstituted C5 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C18 aryl group, or a substituted or unsubstituted C6 to C18 aryl group thereof. It can be a combination.

The substituted or unsubstituted C3 to C10 alkyl group is a substituted or unsubstituted propyl group, a substituted or unsubstituted isopropyl group, a substituted or unsubstituted n-butyl group, a substituted or unsubstituted isobutyl group, a substituted or unsubstituted It may be an unsubstituted sec-butyl group, a substituted or unsubstituted tert-butyl group, or a substituted or unsubstituted 2,2-dimethylpropyl group.

The substituted or unsubstituted C5 to C8 cycloalkyl group may be a substituted or unsubstituted cyclopentyl group, a substituted or unsubstituted cyclohexyl group, a substituted or unsubstituted cycloheptyl group, or a substituted or unsubstituted cyclooctyl group. there is.

The substituted or unsubstituted C6 to C18 aryl group may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted naphthyl group.

The compound represented by Formula 2 may be at least one selected from Group 1 below.

[Group 1]

The photoacid generator (PAG) may include a cationic compound represented by the following Chemical Formula 3, Chemical Formula 4, or Chemical Formula 5.

[Formula 3]

[Formula 4]

[Formula 5]

In Formulas 3 to 5,

M ¹ is F, Cl, Br, or I,

M ² is O, S, Se, or Te,

M ³ is N, P, As, or Sb,

R ²⁸ to R ³⁶ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

The photoacid generator (PAG) may include a cationic compound represented by Formula 6 or Formula 7 below.

[Formula 6]

[Formula 7]

In Formula 6 and Formula 7,

R ³⁷ to R ⁴¹ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

The composition for semiconductor photoresist includes 1% to 30% by weight of an acrylic polymer containing a structural unit represented by Formula 1, 0.01% to 3% by weight of a compound represented by Formula 2, and 0.1% by weight of a photoacid generator (PAG). It may contain from 5% by weight to 5% by weight and the remaining amount of solvent.

With respect to 100 parts by weight of the acrylic polymer containing the structural unit represented by Formula 1, the compound represented by Formula 2 is included in an amount of 1 to 20 parts by weight, and the photoacid generator is included in an amount of 1 to 20 parts by weight. You can.

The composition for semiconductor photoresist may further include additives such as a quencher, a surfactant, an acid increasing agent, a dye, a plasticizer, a photosensitizer, a light absorber, an alkali-soluble resin, a dissolution inhibitor, a dissolution accelerator, or a combination thereof. You can.

A pattern forming method according to another embodiment includes forming a film to be etched on a substrate, forming a photoresist film by applying the composition for a semiconductor photoresist described above on the film to be etched, patterning the photoresist film to form a photoresist pattern. It includes forming and etching the etch target layer using the photoresist pattern as an etch mask.

The step of forming the photoresist pattern may use light with a wavelength of 100 nm to 300 nm.

The pattern forming method may further include providing a resist underlayer formed between the substrate and the photoresist layer.

Since the composition for a semiconductor photoresist according to one embodiment has relatively excellent resolution, it is possible to provide a photoresist pattern that has excellent limiting resolution and does not collapse even if the composition has a high aspect ratio.

1 to 5 are cross-sectional views illustrating a method of forming a pattern using a composition for semiconductor photoresist according to an embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, in explaining this description, descriptions of already known functions or configurations will be omitted to make the gist of this description clear.

In order to clearly explain this description, parts that are not related to the description have been omitted, and identical or similar components are given the same reference numerals throughout the specification. In addition, the size and thickness of each component shown in the drawings are shown arbitrarily for convenience of explanation, so the present description is not necessarily limited to what is shown.

In the drawing, the thickness is enlarged to clearly express various layers and areas. Also, in the drawing, the thickness of some layers and regions is exaggerated for convenience of explanation. When a part of a layer, membrane, region, plate, etc. is said to be “on” or “on” another part, this includes not only cases where it is “directly above” another part, but also cases where there is another part in between.

In this description, “substitution” means that the hydrogen atom is deuterium, halogen group, hydroxy group, cyano group, nitro group, -NRR' (where R and R' are each independently hydrogen, substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or substituted or unsubstituted C6 to C30 aromatic hydrocarbon group), -SiRR'R” (where R, R ', and R" are each independently hydrogen, a substituted or unsubstituted C1 to C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3 to C30 saturated or unsaturated alicyclic hydrocarbon group, or a substituted or unsubstituted C1 to C30 saturated or unsaturated alicyclic hydrocarbon group. C6 to C30 aromatic hydrocarbon group), C1 to C30 alkyl group, C1 to C10 haloalkyl group, C1 to C10 alkylsilyl group, C3 to C30 cycloalkyl group, C6 to C30 aryl group, C1 to C20 alkoxy group, or a combination thereof. It means replaced. “Unsubstituted” means that a hydrogen atom remains a hydrogen atom without being substituted with another substituent.

In this specification, “alkyl group” means a straight-chain or branched-chain aliphatic hydrocarbon group, unless otherwise defined. The alkyl group may be a “saturated alkyl group” that does not contain any double or triple bonds.

The alkyl group may be a C1 to C20 alkyl group. For example, the alkyl group may be a C3 to C20 alkyl group, a C3 to C18 alkyl group, a C3 to C16 alkyl group, or a C3 to C10 alkyl group. For example, the C3 to C10 alkyl group may be a propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, or tert-butyl group, or 2,2-dimethylpropyl group.

As used herein, unless otherwise defined, “alkenyl group” refers to a straight-chain or branched aliphatic hydrocarbon group and an aliphatic unsaturated alkenyl group containing one or more double bonds. do.

In this specification, unless otherwise defined, “alkynyl group” refers to a straight-chain or branched aliphatic hydrocarbon group and an aliphatic unsaturated alkynyl group containing one or more triple bonds. do.

In this specification, “aryl group” refers to a substituent in which all elements of a cyclic substituent have p-orbitals, and these p-orbitals form conjugation, and are monocyclic or fused. Contains ring polycyclic (i.e. rings splitting adjacent pairs of carbon atoms) functional groups.

As used herein, “heteroaryl group” means that the aryl group contains at least one hetero atom selected from the group consisting of N, O, S, P, and Si. Two or more heteroaryl groups may be directly connected through a sigma bond, or when the heteroaryl group includes two or more rings, the two or more rings may be fused to each other. When the heteroaryl group is a fused ring, each ring may contain 1 to 3 heteroatoms.

Hereinafter, a composition for a semiconductor photoresist according to an embodiment will be described.

A composition for a semiconductor photoresist according to an embodiment of the present invention includes an acrylic polymer containing a structural unit represented by the following formula (1); A compound represented by the following formula (2); photoacid generator (PAG); and solvents.

[Formula 1]

[Formula 2]

In Formula 1 and Formula 2,

R ^a is hydrogen or a methyl group,

R ¹ is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkoxycarbonyl group, or a halogen group,

R ² to R ⁵ are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C3 to C20 alkenyl group. C20 cycloalkyl group, substituted or unsubstituted C3 to C20 cycloalkenyl group, substituted or unsubstituted C3 to C20 cycloalkynyl group, substituted or unsubstituted C6 to C20 aryl group, substituted or unsubstituted C2 to C20 heteroaryl group. or a combination thereof,

m1 is one of the integers from 1 to 4,

n1 and n2 are each independently integers of 1 or 2.

The compound represented by Formula 2 is a bis-lactone (glcolide) compound containing two lactone structures in one molecule, and can be hydrolyzed into a di-acid compound due to acid generated by exposure to light. At this time, the difference in solubility between the non-exposed area and the exposed area can be maximized by the acid generated, and thus the resolution can be improved.

On the other hand, if di-acid itself, which is a result of the decomposition of lactone, is included before development, the difference in solubility between the developer solution in the unexposed area and the exposed area is reduced, which may deteriorate the resolution.

As an example, R ² to R ⁵ in Formula 2 are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or It could be a combination of these.

When considering solubility in organic solvents, R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C3 to C20 cycloalkyl group. It may be a C6 to C20 aryl group, or a combination thereof.

As a more specific example, R ² to R ⁵ in Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C10 alkyl group, a substituted or unsubstituted C5 to C8 cycloalkyl group, or a substituted or unsubstituted C6 to C18 aryl group. , or a combination thereof.

For example, at least one of R ² to R ⁵ in Formula 2 is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, Substituted or unsubstituted C3 to C20 cycloalkyl group, substituted or unsubstituted C3 to C20 cycloalkenyl group, substituted or unsubstituted C3 to C20 cycloalkynyl group, substituted or unsubstituted C6 to C20 aryl group, substituted or unsubstituted It may be a C2 to C20 heteroaryl group or a combination thereof.

Specifically, at least one of R ² to R ⁵ in Formula 2 is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or It could be a combination of these.

More specifically, at least one of R ² to R ⁵ of Formula 2 is a substituted or unsubstituted C3 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, Or it may be a combination thereof.

Most specifically, at least one of R ² to R ⁵ in Formula 2 is a substituted or unsubstituted C3 to C10 alkyl group, a substituted or unsubstituted C5 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C18 aryl group, Or it may be a combination thereof.

In one embodiment, any one of R ² and R ³ of Formula 2, and any one of R ⁴ and R ⁵ is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, or a substituted or unsubstituted C1 to C20 alkenyl group. or unsubstituted C2 to C20 alkynyl group, substituted or unsubstituted C3 to C20 cycloalkyl group, substituted or unsubstituted C3 to C20 cycloalkenyl group, substituted or unsubstituted C3 to C20 cycloalkynyl group, substituted or unsubstituted It may be a C6 to C20 aryl group, a substituted or unsubstituted C2 to C20 heteroaryl group, or a combination thereof.

In a specific embodiment, any one of R ² and R ³ of Formula 2, and any one of R ⁴ and R ⁵ is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, It may be a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof.

In a more specific embodiment, any one of R ² and R ³ of Formula 2, and any one of R ⁴ and R ⁵ is a substituted or unsubstituted C3 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group. , a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof.

In the most specific embodiment, any one of R ² and R ³ of Formula 2, and any one of R ⁴ and R ⁵ is a substituted or unsubstituted C3 to C10 alkyl group, a substituted or unsubstituted C5 to C8 cycloalkyl group. , a substituted or unsubstituted C6 to C18 aryl group, or a combination thereof.

For example, the substituted or unsubstituted C3 to C10 alkyl group includes a substituted or unsubstituted propyl group, a substituted or unsubstituted isopropyl group, a substituted or unsubstituted n-butyl group, a substituted or unsubstituted isobutyl group, It may be a substituted or unsubstituted sec-butyl group, a substituted or unsubstituted tert-butyl group, or a substituted or unsubstituted 2,2-dimethylpropyl group.

For example, the substituted or unsubstituted C5 to C8 cycloalkyl group is a substituted or unsubstituted cyclopentyl group, a substituted or unsubstituted cyclohexyl group, a substituted or unsubstituted cycloheptyl group, or a substituted or unsubstituted cyclooctyl group. It could be a sign.

For example, the substituted or unsubstituted C6 to C18 aryl group may be a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted naphthyl group.

According to one embodiment, the compound represented by Formula 2 may be at least one selected from Group 1 below.

[Group 1]

The weight average molecular weight (Mw) of the acrylic polymer may be 10,000 to 100,000, for example, 10,000 to 80,000, for example, 10,000 to 60,000, for example, 10,000 to 50,000, for example For example, it may be 10,000 to 20,000.

The polydispersity index (PDI) of the acrylic polymer may be 2.0 or less, for example, 1.1 to 2.0, for example, 1.5 to 1.8.

When the polydispersity index is within the above range, the molecular weight distribution of the polymer becomes small, and resolution can be further improved by using a polymer with such a small molecular weight distribution.

The composition for a semiconductor photoresist according to one embodiment includes 1% to 30% by weight of the above-described acrylic polymer, for example, 1% to 20% by weight, for example, 3% to 20% by weight, for example, 5% by weight. It may be included in weight% to 15% by weight.

The composition for a semiconductor photoresist according to one embodiment includes the compound represented by the above-described formula 2 in an amount of 0.01% to 3% by weight, for example, 0.05% to 1% by weight, for example, 0.05% to 0.5% by weight. It can be included.

In the composition for a semiconductor photoresist according to one embodiment, the compound represented by the above-described formula (2) is contained in an amount of 1 to 20 parts by weight, for example, 1 to 15 parts by weight, based on 100 parts by weight of the acrylic polymer. For example, it may be included in an amount of 1 to 10 parts by weight, or for example, 3 to 10 parts by weight.

When the acrylic polymer containing the structural unit represented by Formula 1 and the compound represented by Formula 2 are included in the corresponding content range, processes such as baking during photoresist formation can be facilitated, adhesion to the substrate is improved, and By improving the sensitivity of the photoresist, the LWR of the resist pattern can be improved.

The composition for a semiconductor resist according to one embodiment includes a photo acid generator (PAG), thereby simultaneously improving the sensitivity and resolution characteristics of the composition for a semiconductor photoresist without deteriorating any one of the characteristics. You can.

A photoacid generator (PAG) is a compound that generates acid by irradiation with active radiation or radiation.

As the photoacid generator, a compound that generates an organic acid upon irradiation of actinic light or radiation is preferable. For example, sulfonium salt compounds, iodonium salt compounds, diazonium salt compounds, phosphonium salt compounds, imide sulfonate compounds, oxime sulfonate compounds, diazodisulfone compounds, disulfone compounds, and o-nitrobenzyl. and sulfonate compounds.

As the photoacid generator, known compounds that generate acids when irradiated with actinic light or radiation can be appropriately selected and used individually or as a mixture thereof.

For example, the photo acid generator (PAG) may include a cationic compound represented by Formula 3, Formula 4, or Formula 5 below.

[Formula 3]

[Formula 4]

[Formula 5]

In Formulas 3 to 5,

M ¹ is F, Cl, Br, or I,

M ² is O, S, Se, or Te,

M ³ is N, P, As, or Sb,

R ²⁸ to R ³⁶ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

More specifically, the photoacid generator (PAG) may include a cationic compound represented by Formula 6 or Formula 7 below.

[Formula 6]

[Formula 7]

In Formula 6 and Formula 7,

R ³⁷ to R ⁴¹ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.

The composition for a semiconductor photoresist according to one embodiment contains the above-described photoacid generator (PAG) in an amount of 0.1% by weight to 5% by weight, for example, 0.3% by weight to 5% by weight, for example, 0.5% by weight to 5% by weight. It can be included.

In the composition for a semiconductor photoresist according to one embodiment, the above-described photoacid generator is used in an amount of 1 to 20 parts by weight, for example, 1 to 15 parts by weight, for example, 100 parts by weight of the acrylic polymer. It may comprise from 3 parts by weight to 10 parts by weight, or for example from 3 parts by weight to 10 parts by weight.

When the photoacid generator (PAG) is included in the composition for a semiconductor photoresist in the above content range, the sensitivity and resolution characteristics can be improved simultaneously without the problem of deterioration of either of the sensitivity and resolution characteristics.

The solvent included in the semiconductor resist composition according to one embodiment may be an organic solvent, for example, alkylene glycol monoalkyl ether carboxylate, alkylene glycol monoalkyl ether, alkyl lactic acid ester, alkyl alkoxypropionic acid, Organic solvents such as cyclic lactones (preferably having 4 to 10 carbon atoms), monoketone compounds that may have rings (preferably having 4 to 10 carbon atoms), alkylene carbonates, alkyl alkoxyacetates, and alkyl pyruvates can be appropriately used. . As an example, a mixed solvent containing a solvent having a hydroxyl group in the structure and a solvent not having a hydroxyl group can be used.

As the solvent having a hydroxyl group and the solvent not having a hydroxyl group, the above-mentioned exemplary compounds can be appropriately selected. Examples of the solvent containing a hydroxyl group include alkylene glycol monoalkyl ether, alkyl lactate, etc., more specifically, Examples include propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether (PGEE), methyl 2-hydroxyisobutyrate, or ethyl lactate. In addition, solvents that do not have a hydroxyl group include alkylene glycol monoalkyl ether acetate, alkylalkoxypropionate, monoketone compounds that may have a ring, cyclic lactone, or alkyl acetate, and more specifically, Propylene glycol monomethyl ether acetate (PGMEA), ethyl ethoxypropionate (specifically, ethyl 3-ethoxypropionate), 2-heptanone, γ-butyrolactone, cyclohexanone, cyclopentanone. , 3-methoxybutyl acetate, or butyl acetate, etc., such as propylene glycol monomethyl ether acetate, γ-butyrolactone, ethyl ethoxypropionate, cyclohexanone, cyclopentanone, or 2. -Heptanone, etc. can be mentioned. Examples of solvents that do not have a hydroxyl group include propylene carbonate.

The most specific example is preferably one containing propylene glycol monomethyl ether acetate, and propylene glycol monomethyl ether acetate is the sole solvent, or a mixture of two or more types containing propylene glycol monomethyl ether acetate. It may be a solvent, but is not limited thereto.

The solvent may be included in the remaining amount in the composition for semiconductor photoresist, specifically 65% by weight to 95% by weight, for example, 70% by weight to 95% by weight, for example, 75% by weight to 95% by weight. can be included. When included in the corresponding content range, it can have appropriate coating properties.

Additionally, the composition for semiconductor resist according to one embodiment may further include additives in some cases. Examples of the additives include quenchers, surfactants, acid multipliers, dyes, plasticizers, photosensitizers, light absorbers, alkali-soluble resins, dissolution inhibitors, dissolution accelerators, or combinations thereof.

The inhibitor acts as a quencher that traps the acid generated from the acid-acid generator or the like during exposure and suppresses the reaction of the acid-decomposable resin in the unexposed area due to the excess acid generated. For example, basic compounds, basic compounds whose basicity is reduced or lost by irradiation with actinic light or radiation, onium salts that are relatively weak acids to acid generators, and groups that have a nitrogen atom and are released by the action of an acid. A low molecular weight compound having a nitrogen atom in the cation portion, an onium salt compound having a nitrogen atom in the cation portion, etc. can be used as an acid diffusion control agent. In the composition of the present invention, known inhibitors can be appropriately used.

The quencher may be diphenyl (p-tryl) amine, methyl diphenyl amine, triphenyl amine, phenylenediamine, naphthylamine, diaminonaphthalene, or a combination thereof.

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

The amount of these additives used can be easily adjusted depending on the desired physical properties, and may be omitted.

In addition, the composition for semiconductor resist may further use a silane coupling agent as an additive as an adhesion promoter to improve adhesion to the substrate (for example, to improve the adhesion of the composition for semiconductor resist to the substrate). The silane coupling agent includes, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyl trichlorosilane, vinyltris(β-methoxyethoxy)silane; or 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, p-styryl trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldi. ethoxysilane; Silane compounds containing carbon-carbon unsaturated bonds such as trimethoxy[3-(phenylamino)propyl]silane may be used, but are not limited thereto.

Meanwhile, according to another embodiment, a method of forming a pattern using the above-described composition for semiconductor photoresist may be provided. As an example, the manufactured pattern may be a photoresist pattern.

Another pattern forming method in one embodiment includes forming a film to be etched on a substrate, forming a photoresist film by applying the composition for a semiconductor photoresist described above on the film to be etched, and patterning the photoresist film to form a photoresist pattern. It includes forming and etching the etch target layer using the photoresist pattern as an etch mask.

Hereinafter, a method of forming a pattern using the above-described composition for semiconductor photoresist will be described with reference to FIGS. 1 to 5. 1 to 5 are cross-sectional views illustrating a method of forming a pattern using a composition for semiconductor photoresist according to the present invention.

Referring to Figure 1, first, an object to be etched is prepared. An example of the object to be etched may be the thin film 102 formed on the semiconductor substrate 100. Hereinafter, only the case where the etching object is the thin film 102 will be described. The surface of the thin film 102 is cleaned to remove contaminants 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, a composition for forming a resist underlayer film 104 is coated on the surface of the cleaned thin film 102 using a spin coating method. However, one embodiment is not necessarily limited to this, and various known coating methods such as spray coating, dip coating, knife edge coating, and printing methods such as inkjet printing and screen printing may be used.

The resist underlayer coating process can be omitted, and the case of coating the resist underlayer film will be described below.

Afterwards, a drying and baking process is performed to form a resist underlayer film 104 on the thin film 102. The baking treatment may be performed at about 100 to about 500°C, for example, about 100°C to about 300°C.

The resist underlayer 104 is formed between the substrate 100 and the photoresist film 106, so that radiation reflected from the interface or interlayer hardmask of the substrate 100 and the photoresist film 106 is not intended. In the case of scattering into an unapplied photoresist area, non-uniformity of the photoresist line width and interference with pattern formation can be prevented.

Referring to Figure 2, the photoresist film 106 is formed by coating the above-described semiconductor photoresist composition on the resist underlayer film 104. The photoresist film 106 may be formed by coating the above-described semiconductor photoresist composition on the thin film 102 formed on the substrate 100 and then curing it through a heat treatment process.

More specifically, the step of forming a pattern using a semiconductor photoresist composition involves applying the above-described semiconductor resist composition to the substrate 100 on which the thin film 102 is formed by spin coating, slit coating, inkjet printing, etc. It may include a process of forming a photoresist film 106 by drying the applied semiconductor photoresist composition.

Since the composition for semiconductor photoresist has already been described in detail, redundant description will be omitted.

Next, a first baking process is performed to heat the substrate 100 on which the photoresist film 106 is formed. The first baking process may be performed at a temperature of about 80°C to about 120°C.

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

For example, examples of light that can be used in the exposure process include light with a short wavelength such as activating radiation i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), and ArF excimer laser (wavelength 193 nm), as well as EUV (wavelength 193 nm). Examples include light with high energy wavelengths such as Extreme UltraViolet (wavelength 13.5 nm) and E-Beam (electron beam).

More specifically, it may be far ultraviolet light with a wavelength range of 100 nm to 300 nm, for example, a KrF excimer laser (248 nm), an ArF excimer laser (193 nm), an F ₂ excimer laser (157 nm), etc., or a KrF excimer laser or ArF excimer lasers are preferred, and KrF excimer lasers are more preferred.

The resist composition of the present invention is preferably used to form a resist film that is subjected to exposure by a light source with a wavelength of 250 nm or less.

As the exposed area 106a of the photoresist film 106, that is, the area not covered by the patterned hard mask 110, changes to the property of being soluble in the developer, the unexposed area of the photoresist film 106 It has a different solubility from region 106b.

Next, a second baking process is performed on the substrate 100. The second baking process may be performed at a temperature of about 90°C to about 200°C. By performing the second baking process, the unexposed area 106b of the photoresist film 106 becomes difficult to dissolve in the developer.

FIG. 4 shows a photoresist pattern 108 formed by dissolving and removing the photoresist film 106a corresponding to the exposed area using a developer.

Specifically, the developer may be an alkaline developer or a developer containing an organic solvent (hereinafter referred to as an organic developer).

As an alkaline developer, quaternary ammonium salts such as tetramethylammonium hydroxide are usually used, but alkaline aqueous solutions such as inorganic alkalis, primary to tertiary amines, alcohol amines, and cyclic amines can also be used.

Additionally, the alkaline developer may contain an appropriate amount of alcohol and/or surfactant. The alkali concentration of the alkaline developer may be, for example, 0.1 to 20% by mass, and the pH of the alkaline developer may be, for example, 10 to 15.

The organic developer may be a developer containing at least one organic solvent selected from the group consisting of ketone-based solvents, ester-based solvents, alcohol-based solvents, amide-based solvents, ether-based solvents, and hydrocarbon-based solvents.

Examples of ketone solvents include 1-octanone, 2-octanone, 1-nonanone, 2-nonanone, acetone, 2-heptanone (methyl amyl ketone), 4-heptanone, 1-hexanone, 2-hexanone, diisobutyl ketone, cyclohexanone, methylcyclohexanone, phenylacetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, acetonyl acetone, ionone, diacetonyl alcohol, acetyl carbinol, Acetophenone, methylnaphthyl ketone, isophorone, and propylene carbonate can be mentioned.

Examples of ester solvents include methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, pentyl acetate, isopentyl acetate, amyl acetate, propylene glycol monomethyl ether acetate, and ethylene glycol monoethyl ether acetate. , Ethylene Glycol Monobutyl Ether Acetate, Ethylene Glycol Monoethyl Ether Acetate, Ethyl-3-ethoxypropionate, 3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate , methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, butyl butanoate, methyl 2-hydroxyisobutyrate, isoamyl acetate, isobutyl isobutyrate, and butyl propionate. there is.

Known solvents can be used as the alcohol-based solvent, amide-based solvent, ether-based solvent, and hydrocarbon-based solvent.

A plurality of the above solvents may be mixed, or they may be mixed with solvents other than the above or water. The moisture content of the entire developing solution is preferably less than 50% by weight, more preferably less than 20% by weight, more preferably less than 10% by weight, and it is especially preferable that it contains substantially no moisture.

The content of the organic solvent in the organic developer is preferably 50% by weight to 100% by weight, more preferably 80% by weight to 100% by weight, and more preferably 90% by weight to 100% by weight, based on the total amount of the developer. And 95% by weight to 100% by weight is particularly preferable.

The organic developer may contain an appropriate amount of a known surfactant as needed.

The content of the surfactant is usually 0.001% by weight to 5% by weight, preferably 0.005% by weight to 2% by weight, and more preferably 0.01% by weight to 0.5% by weight, based on the total amount of the developer.

The organic developer may contain the above-mentioned inhibitor.

Next, the resist underlayer 104 is etched using the photoresist pattern 108 as an etch mask. The organic layer pattern 112 is formed through the etching process described above. The formed organic layer pattern 112 may also have a width corresponding to the photoresist pattern 108 .

Referring to FIG. 5, the photoresist pattern 108 is applied as an etch mask to etch the exposed thin film 102. As a result, the thin film is formed as a thin film pattern 114.

The etching of the thin film 102 may be performed, for example, by dry etching using an etching gas. The etching gas may be, for example, CHF ₃ , CF ₄ , Cl ₂ , BCl ₃ , or a mixture thereof.

Hereinafter, the present invention will be described in more detail through examples related to the production of the above-described composition for semiconductor photoresist. However, the technical features of the present invention are not limited to the following examples.

Synthesis Example 1

Add 25.3 g of 2-cyclohexy-2-hydroxy acetic acid and 1.0 g of p-TsOH to 1000 ml of toluene in a 2,000 ml flask, install a dean-stark trap, heat at 130°C for 6 days, and remove the produced water. . After this, the heating is stopped, the temperature is lowered to room temperature (25°C), and the solvent is removed using a rotary evaporator. The remaining residue is dissolved in ethyl acetate and neutralized with NaHCO ₃ aqueous solution. Afterwards, the organic layer is purified by recrystallization using hexane to obtain the compound of the following formula 2a.

[Formula 2a]

Synthesis Example 2

The compound of Formula 2b below was obtained in the same manner as in Synthesis Example 1, except that isopropyl-2-hydroxy acetic acid was used instead of 2-cyclohexy-2-hydroxy acetic acid.

[Formula 2b]

Synthesis Example 3

A compound of the following formula 2c was obtained in the same manner as in Synthesis Example 1, except that mandelic acid was used instead of 2-cyclohexy-2-hydroxy acetic acid.

[Formula 2c]

Synthesis Example 4

In a 1000ml round flask, dissolve 97.3g of Acetoxystyrene (Songwon Co., Ltd.) and 76.9g of Ethoxy ethoxy Styrene at a mole ratio of 6:4 in 500ml of Dioxane and add 2,2'-azobis isobutyronitrile (AIBN) as an initiator. Add 5 mol% of Daejeong Chemical Gold Co., Ltd. Heat at 80℃ for 5 hours and check the desired molecular weight by GPC. After the deacetal reaction is performed with an aqueous NaHCO ₃ solution, unreacted monomers and metal impurities are removed through water washing several times to obtain poly hydroxy styrene-co-ethoxy ethoxy styrene (6:4) polymer. (Mw=12,000, PDI 1.7)

(Preparation of photoresist composition)

Example 1

6 parts by weight of Bis(tertbutylsulfonyl)diazomethane (WPAG-170, Wako) as a photo acid generator, based on 100 parts by weight of the poly hydroxy styrene-co-ethoxy ethoxy styrene (6:4) polymer prepared in Synthesis Example 4, As a substitute for 100 parts by weight of the generator, 8 parts by weight of triethanolamine was dissolved in propylene glycol monomethylether acetate (PGMEA) solvent to have a solid content of 10% by weight. Here, the compound of Chemical Formula 2a prepared in Synthesis Example 1 was added in an amount of 5 parts by weight based on 100 parts by weight of the polymer.

Example 2

A composition was prepared in the same manner as Example 1, except that the compound of Formula 2b prepared in Synthesis Example 2 was added instead of the compound of Formula 2a.

Example 3

A composition was prepared in the same manner as in Example 1, except that the compound of Formula 2c prepared in Synthesis Example 3 was added instead of the compound of Formula 2a.

Comparative Example 1

A composition was prepared in the same manner as Example 1, except that the compound of Formula 2a was not added.

Comparative Example 2

A composition was prepared in the same manner as in Example 1, except that pyromellitic dianhydride (Sigma Aldrich) was added instead of the compound of Formula 2a.

Evaluation 1: Development speed

Each composition according to Examples 1 to 3 and Comparative Examples 1 and 2 was spin coated on an 8" bare silicon wafer to a thickness of 4,000 Å, baked at 100°C for 60 seconds, and cooled for about 1 minute. Accordingly, the thickness of the wafer coated with the composition was measured using a thickness gauge (K-MAC). Next, the wafer coated with the composition was mixed with 2.38% by weight of tetramethyl ammonium hydroxide (TMAH). ) was inserted into RDA-760 (Litho Tech Japan) and developed. For each measured wafer, the difference between the initial thickness and the final thickness was measured to calculate the development speed of each protective film developed per hour, This is shown in Table 1 below.

Evaluation 2: Minimum implementation pattern size (nm)

The compositions according to Examples 1 to 3 and Comparative Examples 1 and 2 were spin-coated to a thickness of 5,000 Å on an 8" bare silicon wafer, and soft-baked at 110°C for 60 seconds.

The coated wafer was exposed by splitting the dose with a phase shift mask (PSM) using NSR-S303F (LENS NA: 0.68, sigma: 0.75), a KrF scanner from NIKON. It was developed by puddling for 60 seconds with a 2.38% tetramethyl ammonium hydroxide (TMAH) developer.

Using CD-SEM, the smallest implemented pattern among 1:1 dense patterns was confirmed and the minimum implemented pattern size is shown below.

Developing speed (DR) (nm/s) Minimum implementation pattern size (nm) Example 1 24.4 130 Example 2 32.6 150 Example 3 51.8 150 Comparative Example 1 82.4 180 Comparative Example 2 132.5 200

From the results in Table 1, it can be seen that the semiconductor photoresist compositions according to Examples 1 to 3 are superior to the semiconductor photoresist compositions according to Comparative Examples 1 and 2 in terms of development speed and minimum implemented pattern size.

Although specific embodiments of the present invention have been described and shown above, it is known in the art that the present invention is not limited to the described embodiments, and that various modifications and changes can be made without departing from the spirit and scope of the present invention. This is self-evident to those who have it. Accordingly, such modifications or variations should not be understood individually from the technical idea or viewpoint of the present invention, and the modified embodiments should be regarded as falling within the scope of the claims of the present invention.

100: substrate 102: thin film
104: resist underlayer film 106: photoresist film
106a: exposed area 106b: unexposed area
108: Photoresist pattern 112: Organic film pattern
110: Patterned hardmask
114: thin film pattern

Claims (16)

An acrylic polymer containing a structural unit represented by the following formula (1);
A compound represented by the following formula (2);
photoacid generator (PAG); and
Composition for semiconductor photoresist containing solvent:
[Formula 1]

[Formula 2]

In Formula 1 and Formula 2,
R ^a is hydrogen or a methyl group,
R ¹ is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C1 to C20 alkoxy group, a substituted or unsubstituted C1 to C20 alkoxycarbonyl group, or a halogen group,
R ² to R ⁵ are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C3 to C20 alkenyl group. C20 cycloalkyl group, substituted or unsubstituted C3 to C20 cycloalkenyl group, substituted or unsubstituted C3 to C20 cycloalkynyl group, substituted or unsubstituted C6 to C20 aryl group, substituted or unsubstituted C2 to C20 heteroaryl group. or a combination thereof,
m1 is one of the integers from 1 to 4,
n1 and n2 are each independently integers of 1 or 2. In paragraph 1:
R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or any of these. A composition for a semiconductor photoresist, which is a combination. In paragraph 1:
R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C6 to C20 aryl group, or a substituted or unsubstituted C3 to C20 aryl group thereof. A composition for a semiconductor photoresist, which is a combination. In paragraph 1:
R ² to R ⁵ of Formula 2 are each independently hydrogen, a substituted or unsubstituted C3 to C10 alkyl group, a substituted or unsubstituted C5 to C8 cycloalkyl group, a substituted or unsubstituted C6 to C18 aryl group, or a substituted or unsubstituted C6 to C18 aryl group thereof. A composition for a semiconductor photoresist, which is a combination. In paragraph 4,
The substituted or unsubstituted C3 to C10 alkyl group is a substituted or unsubstituted propyl group, a substituted or unsubstituted isopropyl group, a substituted or unsubstituted n-butyl group, a substituted or unsubstituted isobutyl group, a substituted or unsubstituted A composition for a semiconductor photoresist, which is an unsubstituted sec-butyl group, a substituted or unsubstituted tert-butyl group, or a substituted or unsubstituted 2,2-dimethylpropyl group. In paragraph 4,
The substituted or unsubstituted C5 to C8 cycloalkyl group is a substituted or unsubstituted cyclopentyl group, a substituted or unsubstituted cyclohexyl group, a substituted or unsubstituted cycloheptyl group, or a substituted or unsubstituted cyclooctyl group, Composition for semiconductor photoresist. In paragraph 4,
The substituted or unsubstituted C6 to C18 aryl group is a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted naphthyl group, a composition for a semiconductor photoresist. . In paragraph 1:
A composition for a semiconductor photoresist, wherein the compound represented by Formula 2 is at least one selected from the following group 1:
[Group 1]
. In paragraph 1:
The photoacid generator (PAG) is a composition for a semiconductor photoresist comprising a cationic compound represented by the following Chemical Formula 3, Chemical Formula 4, or Chemical Formula 5:
[Formula 3]

[Formula 4]

[Formula 5]

In Formulas 3 to 5,
M ¹ is F, Cl, Br, or I,
M ² is O, S, Se, or Te,
M ³ is N, P, As, or Sb,
R ²⁸ to R ³⁶ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof. In paragraph 1:
The photoacid generator (PAG) is a composition for a semiconductor photoresist containing a cationic compound represented by the following Chemical Formula 6 or Chemical Formula 7:
[Formula 6]

[Formula 7]

In Formula 6 and Formula 7,
R ³⁷ to R ⁴¹ are each independently a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C2 to C20 aliphatic unsaturated group containing one or more double bonds or triple bonds. It is an organic group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof. In paragraph 1:
1% to 30% by weight of an acrylic polymer containing the structural unit represented by Formula 1, 0.01% to 3% by weight of a compound represented by Formula 2, and 0.1% to 5% by weight of a photoacid generator (PAG). A composition for a semiconductor photoresist containing the balance of a solvent. In paragraph 1:
With respect to 100 parts by weight of an acrylic polymer containing the structural unit represented by Formula 1,
The compound represented by Formula 2 is included in an amount of 1 to 20 parts by weight,
A composition for a semiconductor photoresist, wherein the photoacid generator is included in an amount of 1 to 20 parts by weight. In paragraph 1:
A composition for a semiconductor photoresist further comprising additives such as a quencher, a surfactant, an acid multiplier, a dye, a plasticizer, a photosensitizer, a light absorber, an alkali-soluble resin, a dissolution inhibitor, a dissolution accelerator, or a combination thereof. Forming a film to be etched on a substrate;
forming a photoresist film by applying the composition for a semiconductor photoresist according to any one of claims 1 to 13 on the etching target film;
patterning the photoresist film to form a photoresist pattern; and
A pattern forming method comprising etching the etch target layer using the photoresist pattern as an etch mask. In paragraph 14:
The step of forming the photoresist pattern is a pattern forming method using light with a wavelength of 100 nm to 300 nm. In paragraph 14:
A pattern forming method further comprising providing a resist underlayer formed between the substrate and the photoresist film.