KR102555497B1 - Semiconductor resist composition and method of forming patterns using the composition - Google Patents

Abstract

화학식 1에 대한 구체적인 내용은 명세서 상에서 정의된 것과 같다.It relates to a composition for a semiconductor photoresist comprising an organometallic compound represented by Formula 1 and a solvent, and a pattern formation method using the same.
[Formula 1]

Details of Formula 1 are as defined in the specification.

Description

Composition for semiconductor photoresist and pattern formation method using the same

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

As one of the element technologies for manufacturing next-generation semiconductor devices, EUV (extreme ultraviolet light) lithography is attracting attention. EUV lithography is a pattern formation technique using EUV light with a wavelength of 13.5 nm as an exposure light source. According to EUV lithography, it has been demonstrated that an extremely fine pattern (for example, 20 nm or less) can be formed in an exposure step of a semiconductor device manufacturing process.

Implementation of extreme ultraviolet (EUV) lithography requires the development of compatible photoresists capable of performing at sub-16 nm spatial resolutions. Currently, traditional chemically amplified (CA) photoresists have a significant impact on resolution, photospeed, and feature roughness, line edge roughness (LER) for next-generation devices. We are working hard to meet the specifications.

Intrinsic image blur due to acid catalyzed reactions occurring in these polymeric photoresists limits resolution at small feature sizes, which e-beam This is a long-known fact in lithography. Chemically amplified (CA) photoresists are designed for high sensitivity, but in part because their typical elemental makeup lowers the absorbance of photoresists at a wavelength of 13.5 nm and consequently reduces sensitivity. may suffer more under EUV exposure.

CA photoresists can also suffer from roughness issues at small feature sizes and, due in part to the nature of acid catalyzed processes, line edge roughness (LER) as photospeed decreases. It has been shown experimentally that Due to the drawbacks and problems of CA photoresists, there is a need in the semiconductor industry for new types of high performance photoresists.

Inorganic photoresists based on tungsten and peroxopolyacids of tungsten mixed with niobium, titanium, and/or tantalum are radiation sensitive materials for patterning. (US5061599; H. Okamoto, T. Iwayanagi, K. Mochiji, H. Umezaki, T. Kudo, Applied Physics Letters, 49(5), 298-300, 1986).

These materials have been effective at patterning large features in bilayer configurations with deep UV, x-ray, and e-beam sources. More recently, a cationic hafnium metal oxide sulfate (HfSOx) material was used with a peroxo complexing agent to image 15 nm half-pitch (HP) by projection EUV exposure. impressive performance when used (US2011-0045406; J. K. Stowers, A. Telecky, M. Kocsis, B. L. Clark, D. A. Keszler, A. Grenville, C. N. Anderson, P. P. Naulleau, Proc. SPIE, 7969, 796915, 2011) . This system exhibits the best performance of a non-CA photoresist and has a speed of light approaching the requirements for a viable EUV photoresist. However, hafnium metal oxide sulfate materials with peroxo complexing agents have several practical drawbacks. First, these materials are coated in a highly corrosive sulfuric acid/hydrogen peroxide mixture and have poor shelf-life stability. Second, as a complex mixture, it is not easy to change the structure for performance improvement. Third, it must be developed in a solution of TMAH (tetramethylammonium hydroxide) at an extremely high concentration of about 25 wt%.

In order to overcome the disadvantages of the above-described chemically amplified (CA) photosensitive composition, inorganic photosensitive compositions have been studied. In the case of an inorganic photosensitive composition, it is mainly used for negative tone patterning that is resistant to removal by a developer composition due to chemical modification by a non-chemically amplified mechanism. Inorganic compositions contain inorganic elements with higher EUV absorption than hydrocarbons, so sensitivity can be secured even with a non-chemically amplified mechanism, and they are less sensitive to stochastic effects, so they are known to have less line edge roughness and fewer defects. .

Recently, as it is known that tin-containing molecules have excellent extreme ultraviolet absorption, active research is being conducted. In the case of organotin polymer, which is one of them, as the alkyl ligand is dissociated by light absorption or secondary electrons generated thereby, negative tone patterning that is not removed by an organic developer is possible through crosslinking through oxo bonds with surrounding chains. Such an organotin polymer has been shown to dramatically improve sensitivity while maintaining resolution and line edge roughness, but additional improvement in the patterning characteristics is required for commercialization.

One embodiment provides a composition for a semiconductor photoresist having excellent resolution, etch resistance, pattern formation and storage stability.

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

A composition for a semiconductor photoresist according to an embodiment includes an organometallic compound represented by Formula 1 below and a solvent.

[Formula 1]

In Formula 1,

X ¹ to X ⁴ are each independently -OR ¹ or -OC(=O)R ² ;

R ¹ is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C2 to C20 alkynyl group. A ringed C6 to C30 aryl group, or a combination thereof;

R ² is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C2 to C20 alkynyl group, An unsubstituted C6 to C30 aryl group, or a combination thereof.

R ¹ is a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, a substituted or unsubstituted C2 to C8 alkynyl group, or a substituted or unsubstituted C2 to C8 alkynyl group. A ringed C6 to C20 aryl group, or a combination thereof;

R ² is hydrogen, a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, a substituted or unsubstituted C2 to C8 alkynyl group, or a substituted or unsubstituted C2 to C8 alkynyl group. Or an unsubstituted C6 to C20 aryl group, or a combination thereof.

R ¹ is a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, a tert-butyl group, a 2,2-dimethylpropyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an ethenyl group, A propenyl group, a butenyl group, an ethynyl group, a propynyl group, a butynyl group, a phenyl group, a tolyl group, a xylene group, a benzyl group, or a combination thereof;

R ² is hydrogen, methyl group, ethyl group, propyl group, butyl group, isopropyl group, tert-butyl group, 2,2-dimethylpropyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, ether It may be a yl group, a propenyl group, a butenyl group, an ethynyl group, a propynyl group, a butynyl group, a phenyl group, a tolyl group, a xylene group, a benzyl group, or a combination thereof.

The compound represented by Formula 1 is a compound represented by Formula 2 below, a compound represented by Formula 3 below, a compound represented by Formula 4 below, a compound represented by Formula 5 below, a compound represented by Formula 6 below, and a compound represented by Formula 6 below. The compound represented by 7, or a combination thereof.

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

In Formulas 2 to 6,

The definitions of R ^a , R ^b , R ^c , R ^d , R ^f , R ^g , R ^h , R ^k , R ^l , and R ^p are the same as those for R ² in Formula 1,

The definitions of R ^e , R ⁱ , R ^j , R ^m , R ⁿ , R ^o , R ^q , R ^r , R ^s , and R ^t are the same as those for R ¹ in Formula 1 above.

In the composition for semiconductor photoresist, at least one of X ¹ to X ⁴ may be -OC(=O)R ² .

In the semiconductor photoresist composition, at least three of X ¹ to X ⁴ may be -OC(=O)R ² .

The composition for semiconductor photoresist contains 0.01 to 30% by weight, preferably 0.01 to 15% by weight, more preferably 0.01 to 10% by weight of the organometallic compound represented by Chemical Formula 1, based on 100% by weight of the composition for semiconductor photoresist. % by weight.

The composition for a semiconductor photoresist may further include an additive such as a surfactant, a crosslinking agent, a leveling agent, or a combination thereof.

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

The forming of the photoresist pattern may use light having a wavelength of 5 nm to 150 nm.

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

The photoresist pattern may have a width of 5 nm to 100 nm.

The composition for a semiconductor photoresist according to an embodiment has relatively improved etch resistance and resolution, excellent pattern formation, and excellent storage stability, so that the pattern does not collapse even if it has a high aspect ratio. A photoresist pattern may be provided.

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 accompanying drawings. However, in describing the present description, descriptions of already known functions or configurations will be omitted to clarify the gist of the present description.

In order to clearly describe the description, parts irrelevant to the description have been omitted, and the same reference numerals are used for the same or similar components throughout the specification. In addition, since the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of description, the present description is not necessarily limited to those shown.

In the drawings, the thickness is shown enlarged to clearly express the various layers and regions. Also, in the drawings, the thicknesses of some layers and regions are exaggerated for convenience of explanation. When a part such as a layer, film, region, plate, etc. is said to be "on" or "on" another part, this includes not only the case where it is "directly on" the other part, but also the case where there is another part in between.

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

In this specification, "alkyl (alkyl) group" means a straight-chain or branched-chain aliphatic hydrocarbon group unless otherwise defined. An 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 C8 alkyl group. For example, the alkyl group may be a C1 to C7 alkyl group, a C1 to C6 alkyl group, a C1 to C5 alkyl group, or a C1 to C4 alkyl group. For example, the C1 to C4 alkyl group may be a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or a tert-butyl group or a 2,2-dimethylpropyl group.

In the present description, "cycloalkyl group" means a monovalent cyclic aliphatic saturated hydrocarbon group unless otherwise defined.

The cycloalkyl group may be a C3 to C8 cycloalkyl group, for example, a C3 to C7 cycloalkyl group, a C3 to C6 cycloalkyl group, a C3 to C5 cycloalkyl group, or a C3 to C4 cycloalkyl group. For example, the cycloalkyl group may be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, or a cyclohexyl group, but is not limited thereto.

In this specification, "aliphatic unsaturated organic group" refers to a hydrocarbon group including a bond in which the bond between carbon atoms in a molecule is a double bond, a triple bond, or a combination thereof.

The aliphatic unsaturated organic group may be a C2 to C8 aliphatic unsaturated organic group. For example, the aliphatic unsaturated organic group may be a C2 to C7 aliphatically unsaturated organic group, a C2 to C6 aliphatic unsaturated organic group, a C2 to C5 aliphatic unsaturated organic group, or a C2 to C4 aliphatically unsaturated organic group. For example, a C2 to C4 aliphatic unsaturated organic group is a vinyl group, an ethynyl group, an allyl group, a 1-propenyl group, a 1-methyl-1-propenyl group, a 2-propenyl group, a 2-methyl-2-propenyl group, a 1- Propynyl group, 1-methyl-1propynyl group, 2-propynyl group, 2-methyl-2-propynyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-butynyl group, 2 -It may be a butynyl group or a 3-butynyl group.

In the present specification, "aryl group" means 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 a ring polycyclic (ie, a ring having split adjacent pairs of carbon atoms) functional groups.

In the present specification, “alkenyl group” is a straight-chain or branched-chain aliphatic hydrocarbon group, unless otherwise defined, and means an aliphatic unsaturated alkenyl group containing one or more double bonds. do.

In the present specification, "alkynyl group" is a straight-chain or branched-chain aliphatic hydrocarbon group, unless otherwise defined, and means an aliphatic unsaturated alkynyl group containing one or more triple bonds. do.

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 organometallic compound represented by Formula 1 below and a solvent.

[Formula 1]

In Formula 1,

X ¹ to X ⁴ are each independently -OR ¹ or -OC(=O)R ² ;

R ¹ is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C2 to C20 alkynyl group. A ringed C6 to C30 aryl group, or a combination thereof;

R ² is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C2 to C20 alkynyl group, An unsubstituted C6 to C30 aryl group, or a combination thereof.

In the organometallic compound represented by Formula 1, four X ¹ to X ⁴ organic ligands are bonded to a tin atom, and the X ¹ to X ⁴ are each independently -OR ¹ or -OC(=O)R ² can That is, in the organometallic compound represented by Chemical Formula 1, the tin atom does not directly bond to the carbon atom (C), but forms a ligand while bonding to the oxygen atom (O).

The organometallic compound represented by Chemical Formula 1 is an organotin compound, and tin strongly absorbs extreme ultraviolet light at 13.5 nm and has excellent sensitivity to light having high energy. In addition, the compound of Formula 1 may impart solubility in an organic solvent to an organotin compound as four -OR ¹ or -OC(=O)R ² are bonded to a tin element, and a semiconductor photovoltaic device including the same Etch resistance, resolution, and pattern formation of the resist composition can be improved, and storage stability and coating properties can be improved.

Each of the four organic ligands, X ¹ to X ⁴ , may be hydrolyzed to form a Sn-O bond, and these organic ligands are hydrolyzed by heat treatment under an acidic or basic catalyst or not by heat treatment, resulting in organotin compounds. An inter-Sn-O-Sn bond is formed, thereby forming an organotin copolymer including the organometallic compound represented by Chemical Formula 1.

At this time, since all four organic ligands of the organometallic compound represented by Chemical Formula 1 consist of Sn-O bonds and there is no Sn-C bond, the composition for semiconductor photoresist including the organic ligands is relatively stable when exposed to extreme ultraviolet rays. Storage stability may be improved compared to a composition for a semiconductor photoresist including an organometallic compound having an easily dissociated Sn-C bond.

In addition, specifically, since the bond between the tin atom and -OC(=O)R ² requires more energy for dissociation of the bond when exposed to extreme ultraviolet rays than the bond between the tin atom and -OR ¹ , the organometallic compound As the number of -OC(=O)R ² substituents increases, the storage stability of the composition for semiconductor photoresist including the organometallic compound may be further improved.

The organometallic compound forms cross-linked bonds through oxo bonds with neighboring chains by radicals generated as ligands of X ¹ to X ⁴ dissociate, and as a result, has low line edge roughness and excellent resolution while maintaining storage stability. An excellent semiconductor photoresist can be provided.

Wherein R ¹ is, for example, a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, or a substituted or unsubstituted C2 to C8 alkyi group. It may be a yl group, a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof, for example, a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, a tert-butyl group, a 2,2-dimethyl A propyl group, a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, an ethenyl group, a propenyl group, a butenyl group, an ethynyl group, a propynyl group, a butynyl group, a phenyl group, a tolyl group, a xylene group, a benzyl group, or It may be a combination of these.

R ² is, for example, hydrogen, a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, a substituted or unsubstituted C2 to C8 alkenyl group, or a substituted or unsubstituted C2 to C8 cycloalkyl group. It may be a C8 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof, for example, hydrogen, methyl group, ethyl group, propyl group, butyl group, isopropyl group, tert-butyl group, 2 ,2-dimethylpropyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, ethenyl group, propenyl group, butenyl group, ethynyl group, propynyl group, butynyl group, phenyl group, tolyl group, xylene group, benzyl group, or a combination thereof.

The compound represented by Formula 1 is a compound represented by Formula 2 below, a compound represented by Formula 3 below, a compound represented by Formula 4 below, a compound represented by Formula 5 below, a compound represented by Formula 6 below, and a compound represented by Formula 6 below. The compound represented by 7, or a combination thereof.

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

In Formulas 2 to 6,

The definitions of R ^a , R ^b , R ^c , R ^d , R ^f , R ^g , R ^h , R ^k , R ^l , and R ^p are the same as those for R ² in Formula 1,

The definitions of R ^e , R ⁱ , R ^j , R ^m , R ⁿ , R ^o , R ^q , R ^r , R ^s , and R ^t are the same as those for R ¹ in Formula 1 above.

In the organometallic compound represented by Chemical Formula 1, at least one of four X ¹ to X ⁴ may be -OC(=O)R ² , and at least two of them may be -OC(=O)R ² . And, at least three or more may be -OC(=O)R ² , or all four may be -OC(=O)R ² . In this regard, as described above, since the bond between the tin atom and -OC(=O)R ² requires more energy to dissociate during EUV exposure than the bond between the tin atom and -OR ¹ , the above As the number of -OC(=O)R ² substituents in the organometallic compound increases, the storage stability of the composition for semiconductor photoresist including the organometallic compound may be further improved.

The composition for semiconductor photoresist contains 0.01 wt% or more, 0.05 wt% or more, 0.1 wt% or more, 0.5 wt% or more, 1.0 wt% or more of the organometallic compound represented by Chemical Formula 1, based on 100 wt% of the semiconductor photoresist composition. % or more, 2.0 wt% or more, 3,0 wt% or more, 4.0 wt% or more, or 5.0 wt% or more and 30 wt% or less, 28 wt% or less, 25 wt% or less, 23 wt% or less, 20 wt% or less , 18 wt% or less, 15 wt% or less, 13 wt% or less, or 10 wt% or less, but is not limited thereto. Since the semiconductor photoresist composition according to an embodiment includes the organometallic compound represented by Chemical Formula 1 in the above range, processes such as coating can be facilitated when forming a photoresist from the composition, and pattern formation of the photoresist can be improved. can improve

The solvent included in the semiconductor resist composition according to an embodiment may be an organic solvent, and for example, aromatic compounds (eg, xylene, toluene), alcohols (eg, 4-methyl-2-pentanol) , 4-methyl-2-propanol, 1-butanol, methanol, isopropyl alcohol, 1-propanol), ethers (e.g., anisole, tetrahydrofuran), esters (n-butyl acetate, propylene glycol mono methyl ether acetate, ethyl acetate, ethyl lactate), ketones (eg, methyl ethyl ketone, 2-heptanone), mixtures thereof, and the like, but are not limited thereto.

In one embodiment, the semiconductor resist composition may further include a resin in addition to the organic metal compound and the solvent.

The resin may be a phenolic resin containing at least one of the aromatic moieties listed in Group 1 below.

[Group 1]

The resin may have a weight average molecular weight of 500 to 20,000.

The resin may be included in an amount of 0.1 wt% to 50 wt% based on the total amount of the composition for semiconductor resist.

When the resin is contained in the above content range, it may have excellent corrosion resistance and heat resistance.

Meanwhile, the composition for a semiconductor resist according to one embodiment is preferably composed of the above-described organometallic compound, a solvent, and a resin. However, the composition for a semiconductor resist according to the above-described embodiment may further include an additive according to circumstances. Examples of such additives include surfactants, crosslinking agents, leveling agents, or combinations thereof.

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

The crosslinking agent may include, for example, a melamine-based crosslinking agent, a substituted urea-based crosslinking agent, or a polymer-based crosslinking agent, but is not limited thereto. crosslinking agents having at least two crosslinking substituents, for example methoxymethylated glycoluril, butoxymethylated glycoluril, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine , Compounds such as methoxymethylated urea, butoxymethylated urea, or methoxymethylated thiourea can be used.

The leveling agent is for improving coating flatness during printing, and a known leveling agent available commercially may be used.

The amount of these additives used can be easily adjusted according to desired physical properties and may be omitted.

In addition, the composition for semiconductor resist may further use a silane coupling agent as an additive to improve adhesion to a substrate (for example, to improve adhesion of the composition for semiconductor resist to a substrate). Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, and vinyltris(β-methoxyethoxy)silane; Or 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, p-styryl trimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldi ethoxysilane; A carbon-carbon unsaturated bond-containing silane compound such as trimethoxy[3-(phenylamino)propyl]silane may be used, but is not limited thereto.

The composition for semiconductor photoresist may not cause pattern collapse even when a pattern having a high aspect ratio is formed. Therefore, for example, a fine pattern having a width of 5 nm to 100 nm, for example, a fine pattern having a width of 5 nm to 80 nm, for example, a fine pattern having a width of 5 nm to 70 nm, for example, a fine pattern having a width of 5 nm to 80 nm. A fine pattern having a width of 50 nm, for example, a fine pattern having a width of 5 nm to 40 nm, for example, a fine pattern having a width of 5 nm to 30 nm, for example, a fine pattern having a width of 5 nm to 20 nm To form, a photoresist process using light of a wavelength of 5 nm to 150 nm, for example, a photoresist process using light of a wavelength of 5 nm to 100 nm, for example, a photoresist process using light of a wavelength of 5 nm to 80 nm , For example, a photoresist process using light with a wavelength of 5 nm to 50 nm, for example, a photoresist process using light with a wavelength of 5 nm to 30 nm, for example, a photoresist using light with a wavelength of 5 nm to 20 nm can be used in the process. Accordingly, extreme ultraviolet lithography using an EUV light source having a wavelength of about 13.5 nm can be implemented by using the composition for a semiconductor photoresist according to one embodiment.

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

Another pattern forming method according to an embodiment includes forming a film to be etched on a substrate, forming a photoresist film by applying the composition for semiconductor resist on the film to be etched, and patterning the photoresist film to form a photoresist pattern. 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 resist will be described with reference to FIGS. 1 to 5 . 1 to 5 are cross-sectional views for explaining a pattern formation method using a composition for semiconductor resist according to the present invention.

Referring to FIG. 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 object to be etched 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.

Subsequently, a composition for forming a resist underlayer film for forming a resist underlayer film 104 is coated on the surface of the cleaned thin film 102 by applying a spin coating method. However, one embodiment is not necessarily limited thereto, 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 process of coating the resist underlayer film may be omitted. Hereinafter, the case of coating the resist underlayer film will be described.

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

The resist underlayer film 104 is formed between the substrate 100 and the photoresist film 106 so that radiation reflected from an interface between the substrate 100 and the photoresist film 106 or from an interlayer hardmask is not intended. It is possible to prevent non-uniformity of photoresist linewidth and disturbance of pattern formability in the case of scattering into undesirable photoresist regions.

Referring to FIG. 2 , a photoresist film 106 is formed by coating the above-described composition for semiconductor resist on the resist underlayer film 104 . The photoresist film 106 may be formed by coating the above-described composition for semiconductor resist 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 the composition for semiconductor resist is a process of applying the above-described composition for semiconductor resist on the substrate 100 on which the thin film 102 is formed by spin coating, slit coating, inkjet printing, etc. and drying the applied composition for semiconductor resist to form the photoresist film 106 .

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

Subsequently, a first baking process of 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 about 80 °C to about 120 °C.

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

For example, examples of the light usable in the exposure process include light having a short wavelength such as 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). Extreme UltraViolet (wavelength 13.5nm), light having a high energy wavelength such as E-Beam (electron beam), etc. may be mentioned.

More specifically, light for exposure according to an embodiment may be short-wavelength light having a wavelength range of 5 nm to 150 nm, and may be light having a high energy wavelength such as EUV (Extreme Ultraviolet; wavelength 13.5 nm) or E-Beam (electron beam). .

The exposed region 106b of the photoresist film 106 has a different solubility from the unexposed region 106a of the photoresist film 106 as a polymer is formed by a crosslinking reaction such as condensation between organometallic compounds. .

Subsequently, 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. As a result of performing the second baking process, the exposed region 106b of the photoresist layer 106 becomes difficult to dissolve in a developing solution.

4 shows a photoresist pattern 108 formed by dissolving and removing the photoresist film 106a corresponding to the unexposed area using a developing solution. Specifically, the photoresist pattern corresponding to the negative tone image ( 108) is completed.

As described above, the developer used in the pattern formation method according to an embodiment may be an organic solvent. Examples of the organic solvent used in the pattern formation method according to the embodiment include ketones such as methyl ethyl ketone, acetone, cyclohexanone, and 2-heptanone, 4-methyl-2-propanol, 1-butanol, isopropanol, Alcohols such as 1-propanol and methanol, esters such as propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate, n-butyl acetate and butyrolactone, aromatic compounds such as benzene, xylene and toluene, or these A combination of

However, the photoresist pattern according to one embodiment is not necessarily limited to being formed as a negative tone image, and may be formed to have a positive tone image. In this case, as a developer that can be used for forming a positive tone image, a quaternary ammonium hydroxide composition such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide or a combination thereof, and the like can be heard

As described above, EUV (Extreme UltraViolet; wavelength 13.5nm), E-Beam as well as light having wavelengths such as i-line (wavelength 365nm), KrF excimer laser (wavelength 248nm), and ArF excimer laser (wavelength 193nm) The photoresist pattern 108 formed by exposure to high-energy light such as (electron beam) may have a width of 5 nm to 100 nm. For example, the photoresist pattern 108 has a thickness of 5 nm to 90 nm, 5 nm to 80 nm, 5 nm to 70 nm, 5 nm to 60 nm, 10 nm to 50 nm, 10 nm to 40 nm, 10 nm to 30 nm, and 10 nm to 20 nm. It can be.

On the other hand, the photoresist pattern 108 has a half-pitch of about 50 nm or less, for example, 40 nm or less, for example, 30 nm or less, for example, 25 nm or less, and a line width of about 10 nm or less, about 5 nm or less. It may have a pitch with roughness.

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

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 a thin film pattern 114 .

Etching of the thin film 102 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 or a mixture thereof.

In the previously performed exposure process, the thin film pattern 114 formed using the photoresist pattern 108 formed by the exposure process performed using the EUV light source may have a width corresponding to the photoresist pattern 108. . For example, it may have the same width as the photoresist pattern 108 of 5 nm to 100 nm. For example, the thin film pattern 114 formed by an exposure process performed using an EUV light source has a thickness of 5 nm to 90 nm, 5 nm to 80 nm, 5 nm to 70 nm, 5 nm to 60 nm, and 10 nm to 50 nm, similarly to the photoresist pattern 108. , 10nm to 40nm, 10nm to 30nm, may have a width of 10nm to 20nm, more specifically may be formed with a width of 20nm or less.

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

Example

Synthesis Example 1

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, and add 11.0mL of acetic acid. After heating under reflux for 24 hours, acetic acid is vacuum distilled to obtain the compound of Formula 7 in a yield of 80%.

[Formula 7]

Synthesis Example 2

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, and add 14.4mL of propionic acid. After heating under reflux for 48 hours, propionic acid is vacuum distilled to obtain the compound of Formula 8 in a yield of 80%.

[Formula 8]

Synthesis Example 3

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, and add 17.6mL of butyric acid. After heating under reflux for 48 hours, butyric acid is vacuum distilled to obtain the compound of Formula 9 in a yield of 80%.

[Formula 9]

Synthesis Example 4

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, and add 13.2mL of acrylic acid. After heating under reflux for 48 hours, acrylic acid is vacuum distilled to obtain the compound of Formula 10 in a yield of 40%.

[Formula 10]

Synthesis Example 5

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask and add 16.2mL of methacrylic acid. After heating under reflux for 48 hours, methacrylic acid is vacuum distilled to obtain the compound of Formula 11 in a yield of 40%.

[Formula 11]

Synthesis Example 6

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, and add 7.2mL of formic acid. After heating under reflux for 48 hours, formic acid was vacuum distilled to obtain the compound of Formula 12 in a yield of 40%.

[Formula 12]

Synthesis Example 7

Anhydrous pentane was added to Tin(IV) chloride (5 g, 26.4 mmol), and the temperature was lowered to 0°C. After slowly adding diethylamine (7.1 mL, 105.5 mmol) dropwise, t-BuOH (10 mL, 105.5 mmol) was added thereto, followed by stirring at room temperature for 1 hour. When the reaction is complete, the mixture is filtered, concentrated, and vacuum dried to obtain a compound represented by Formula 13 in a yield of 40%.

[Formula 13]

Synthesis Example 8

Anhydrous pentane was added to Tin(IV) chloride (5 g, 26.4 mmol), and the temperature was lowered to 0°C. After slowly adding diethylamine (7.1 mL, 105.5 mmol) dropwise, (Isopropyl alcohol (8.1 mL, 105.5 mmol)) was added and stirred at room temperature for 1 hour. After the reaction was completed, filter and concentrate. Vacuum drying to obtain a compound represented by the following formula (14) in a yield of 40%.

[Formula 14]

Synthesis Example 9

Anhydrous pentane was added to Tin(IV) chloride (5 g, 26.4 mmol), and the temperature was lowered to 0°C. After slowly adding diethylamine (7.1mL, 105.5mmol) dropwise, ethanol (6.2mL, 105.5mmol) was then added and stirred at room temperature for 1 hour. When the reaction is complete, the mixture is filtered, concentrated, and vacuum dried to obtain a compound represented by Formula 15 in a yield of 40%.

[Formula 15]

Synthesis Example 10

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, add 10mL of toluene, and stir. After adding 1.3 mL of ethanol and heating under reflux for 12 hours, add 2.6 mL of propionic acid and heat under reflux for 24 hours. When the reaction is complete, the mixture is filtered, concentrated, and vacuum dried to obtain a compound represented by Formula 16 in a yield of 50%.

[Formula 16]

Synthesis Example 11

Put 5g (12mmol) of tetraphenyltin in a 100mL round bottom flask, add 10mL of toluene, and stir. After adding 2.6mL of ethanol and heating under reflux for 12 hours, 1.8mL of propionic acid was added and heated under reflux for 24 hours. When the reaction is complete, the mixture is filtered, concentrated, and vacuum dried to obtain a compound represented by Formula 17 in a yield of 50%.

[Formula 17]

Comparative Synthesis Example 1

After dissolving dibutyltin dichloride (10 g, 33 mmol) in 30 mL of ether, 70 mL of 1M sodium hydroxide (NaOH) aqueous solution was added, followed by stirring for 1 hour. After stirring, the resulting solid was filtered, washed three times with 25 mL of deionized water, and dried under reduced pressure at 100° C. to obtain an organometallic compound having a weight average molecular weight of 1,500 g/mol represented by Formula 18 below.

[Formula 18]

Examples 1 to 11

The compounds represented by Chemical Formulas 7 to 17 obtained in Synthesis Examples 1 to 11 were dissolved in 4-methyl-2-pentane at a concentration of 1 wt%, respectively, and 0.1 μm PTFE (polytetrafluoroethylene) syringe filter By filtering, photoresist compositions corresponding to Examples 1 to 11 were prepared.

A circular silicon wafer with a diameter of 4 inches having a native-oxide surface was used as a substrate for thin film coating, and was treated in a UV ozone cleaning system for 10 minutes before coating the thin film. On the treated substrate, the composition for semiconductor photoresist according to Examples 1 to 11 was spin-coated at 1500 rpm for 30 seconds, and baked at 100 ° C. for 120 seconds (post-apply bake, PAB) to obtain a photoresist form a thin film

The thickness of the film after coating and baking was measured through ellipsometry, and the measured thickness was about 25 nm.

Example 12

3 wt% of the compound represented by Formula 7 obtained in Synthesis Example 1 and 2 wt% of the compound represented by Formula 13 obtained in Synthesis Example 7 were simultaneously dissolved in 4-methyl-2-pentane, and 0.1 μm PTFE (polytetrafluorocarbon ethylene) by filtering with a syringe filter to prepare a photoresist composition corresponding to Example 12.

A circular silicon wafer with a diameter of 4 inches having a native-oxide surface was used as a substrate for thin film coating, and was treated in a UV ozone cleaning system for 10 minutes before coating the thin film. On the treated substrate, the composition for semiconductor photoresist according to Example 12 was spin-coated at 1500 rpm for 30 seconds, and baked at 100 ° C. for 120 seconds (post-apply bake, PAB) to form a photoresist thin film. .

The thickness of the film after coating and baking was measured through ellipsometry, and the measured thickness was about 25 nm.

Comparative Example 1

Except for dissolving the compounds obtained in Comparative Synthesis Example 1 in xylene at a concentration of 2 wt%, in the same manner as in Example 1, a semiconductor photoresist composition according to Comparative Example 1 and including the same A photoresist thin film was prepared. The thickness of the film after coating and baking was about 20 nm.

Evaluation 1: Resolution, Line Edge Roughness (LER)

The films according to Examples 1 to 12 and Comparative Example 1 are exposed to extreme ultraviolet rays to form line/space patterns of 18 to 36 nm by varying energy and focus by the coating method on a circular silicon wafer. After exposure, bake at 180℃ for 120 seconds (Post-exposure bake, PEB), then immerse in a petri dish containing 2-heptanone for 60 seconds, take it out, and wash with the same solvent for 10 seconds to avoid exposure. Remove the coated part. Finally, after firing at 150° C. for 5 minutes, a pattern image is obtained by scanning electron microscopy (SEM). The highest resolution, line edge roughness (LER) identified from the SEM images was evaluated according to the following evaluation criteria, and the results are shown in Table 1 below.

- limit resolution

○: 18 nm or less

X: greater than 18 nm

- Line roughness (LER)

○: 2.5 nm or less

X: greater than 2.5 nm

Evaluation 2: Storage stability

After visually observing the degree of precipitation when the photoresist compositions according to Examples 1 to 12 and Comparative Example 1 were left at room temperature (0 ° C to 30 ° C) for a specific period of time, the storage stability criteria were determined according to the following evaluation criteria Evaluated and the results are shown in Table 1 below.

○: Precipitation occurs or does not occur after 1 week

X: occurrence of precipitation in less than 1 week

resolution LER Storage stability Example 1 ○ ○ ○ Example 2 ○ ○ ○ Example 3 ○ ○ ○ Example 4 ○ ○ ○ Example 5 ○ ○ ○ Example 6 ○ ○ ○ Example 7 ○ ○ ○ Example 8 ○ ○ ○ Example 9 ○ ○ ○ Example 10 ○ ○ ○ Example 11 ○ ○ ○ Example 12 ○ ○ ○ Comparative Example 1 X X X

Referring to Table 1, it can be confirmed that the photoresist thin films using the semiconductor photoresist compositions according to Examples 1 to 12 exhibit excellent resolution, line edge roughness (LER), and storage stability characteristics. On the other hand, the photoresist thin film using the composition for semiconductor photoresist according to Comparative Example 1 containing a compound in which a carboxyl group or an alkoxy group is not substituted has excellent resolution and line edge roughness (LER) exceeding 18 nm and 2.5 nm, respectively. It can be seen that it cannot be done, and precipitation occurs for a period of less than 1 week, indicating poor storage stability.

In the foregoing, although specific embodiments of the present invention have been described and shown, the present invention is not limited to the described embodiments, and it is common knowledge in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. It is self-evident to those who have Therefore, such modifications or variations should not be individually understood from the technical spirit or viewpoint of the present invention, and modified embodiments should fall within the scope of the claims of the present invention.

100: substrate 102: thin film
104: photoresist underlayer film 106: photoresist film
106b: exposed area 106a: unexposed area
108: photoresist pattern 112: organic film pattern
114: thin film pattern

Claims (12)

A composition for a semiconductor photoresist comprising an organometallic compound represented by Formula 1 and a solvent:
[Formula 1]

In Formula 1,
X ¹ to X ⁴ are each independently -OR ¹ or -OC(=O)R ² ;
At least one of X ¹ to X ⁴ is -OC(=O)R ² ,
R ¹ is a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, or a substituted or unsubstituted C2 to C20 alkynyl group. A ringed C6 to C30 aryl group, or a combination thereof;
R ² is hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C2 to C20 alkynyl group, An unsubstituted C6 to C30 aryl group, or a combination thereof.
In paragraph 1,
R ¹ is a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, a substituted or unsubstituted C2 to C8 alkynyl group, or a substituted or unsubstituted C2 to C8 alkynyl group A C6 to C20 aryl group, or a combination thereof,
R ² is hydrogen, a substituted or unsubstituted C1 to C8 alkyl group, a substituted or unsubstituted C3 to C8 cycloalkyl group, a substituted or unsubstituted C2 to C8 alkenyl group, a substituted or unsubstituted C2 to C8 alkynyl group, a substituted or unsubstituted C2 to C8 alkynyl group, A composition for a semiconductor photoresist comprising an unsubstituted C6 to C20 aryl group, or a combination thereof.
In paragraph 1,
R ¹ is methyl group, ethyl group, propyl group, butyl group, isopropyl group, tert-butyl group, 2,2-dimethylpropyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, ethenyl group, pro A phenyl group, a butenyl group, an ethynyl group, a propynyl group, a butynyl group, a phenyl group, a tolyl group, a xylene group, a benzyl group, or a combination thereof;
R ² is hydrogen, methyl group, ethyl group, propyl group, butyl group, isopropyl group, tert-butyl group, 2,2-dimethylpropyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, ethenyl group , A propenyl group, a butenyl group, an ethynyl group, a propynyl group, a butynyl group, a phenyl group, a tolyl group, a xylene group, a benzyl group, or a combination thereof.
In paragraph 1,
The compound represented by Formula 1 is for semiconductor photoresists including a compound represented by Formula 2, a compound represented by Formula 3, a compound represented by Formula 4, a compound represented by Formula 5, or a combination thereof Composition:
[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

In Formulas 2 to 5,
R ^a , R ^b , R ^c , R ^d , R ^f , R ^g , R ^h , R ^k , R ^l , and R ^p are each independently hydrogen, a substituted or unsubstituted C1 to C20 alkyl group, substituted or unsubstituted A C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof,
R ^e , R ⁱ , R ^j , R ^m , R ⁿ , and R ^o 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 cycloalkyl group. A C20 alkenyl group, a substituted or unsubstituted C2 to C20 alkynyl group, a substituted or unsubstituted C6 to C30 aryl group, or a combination thereof.
delete In paragraph 1,
At least three or more of the X ¹ to X ⁴ are -OC(=O)R ² The composition for a semiconductor photoresist.
In paragraph 1,
A composition for a semiconductor photoresist comprising 0.01 to 30% by weight of the organometallic compound represented by Formula 1, based on 100% by weight of the composition for a semiconductor photoresist.
In paragraph 1,
The composition for a semiconductor photoresist further comprising an additive of a surfactant, a crosslinking agent, a leveling agent, or a combination thereof.
forming a film to be etched on the substrate;
forming a photoresist layer by applying the composition for a semiconductor photoresist according to any one of claims 1 to 4 and 6 to 8 on the etch target layer;
patterning the photoresist layer to form a photoresist pattern; and
and etching the etch target layer using the photoresist pattern as an etch mask.
In paragraph 9,
The forming of the photoresist pattern is a pattern forming method using light having a wavelength of 5 nm to 150 nm.
In paragraph 9,
The pattern forming method further comprises providing a resist underlayer film formed between the substrate and the photoresist film.
In paragraph 9,
Wherein the photoresist pattern has a width of 5 nm to 100 nm.

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