Semiconductor photoresist composition and method of forming patterns using composition

Abstract

The present invention relates to a semiconductor photoresist composition comprising: an organometallic compound represented by chemical formula 1; and a solvent, and to a method for forming patterns using the composition. Details of chemical formula 1 are as defined in the specification.

Description

Composition for semiconductor photoresist and method for forming a pattern using the same

[0001] The present invention relates to a composition for semiconductor photoresist and a method for forming a pattern using the same.

[0002] EUV (Extreme Ultraviolet) lithography is attracting attention as one of the key technologies for manufacturing next-generation semiconductor devices. EUV lithography is a pattern formation technology that uses EUV light with a wavelength of 13.5 nm as an exposure light source. It has been demonstrated that EUV lithography can form extremely fine patterns (e.g., 20 nm or less) during the exposure process of semiconductor device manufacturing.

[0003] The implementation of extreme ultraviolet (EUV) lithography requires the development of compatible photoresists capable of performing at spatial resolutions of 16 nm or less. Currently, traditional chemically amplified (CA) photoresists are striving to meet specifications for resolution, photospeed, feature roughness, and line edge roughness (LER) for next-generation devices.

[0004] Intrinsic image blur caused by acid-catalyzed reactions occurring in these polymeric photoresists limits resolution at small feature sizes, a fact that has long been known in electron beam lithography. Although chemically amplified (CA) photoresists are designed for high sensitivity, they may face more difficulties under EUV exposure, partly because their typical elemental makeup lowers the absorbance of the photoresists at a wavelength of 13.5 nm, thereby reducing sensitivity.

[0005] CA photoresists can also suffer from roughness issues at small feature sizes, and experiments have shown that line edge roughness (LER) increases as photospeed decreases, partly due to the nature of acid catalyst processes. Due to the defects and problems of CA photoresists, there is a demand in the semiconductor industry for new types of high-performance photoresists.

[0006] Inorganic photosensitive compositions have been studied to overcome the disadvantages of the chemically amplified organic photosensitive compositions described above. Inorganic photosensitive compositions are primarily used for negative tone patterning that is resistant to removal by developer compositions due to chemical modification by non-chemical amplification mechanisms. Inorganic compositions contain inorganic elements that have a higher EUV absorption rate compared to hydrocarbons, so sensitivity can be ensured even by non-chemical amplification mechanisms, and they are known to be less sensitive to stochastic effects, resulting in lower line edge roughness and a smaller number of defects.

[0007] Inorganic photoresists based on tungsten and peroxopolyacids of tungsten mixed with niobium, titanium, and / or tantalum have been reported for use in radiation-sensitive materials for patterning (US5061599; H. Okamoto, T. Iwayanagi, K. Mochiji, H. Umezaki, T. Kudo, Applied Physics Letters, 49(5), 298-300, 1986).

[0008] These materials were effective for patterning large features in bilayer configurations using deep UV, X-ray, and electron beam sources. More recently, impressive performance was shown when using cationic hafnium metal oxide sulfate (HfSOx) materials with a peroxo complexing agent to image a 15 nm half-pitch (HP) by projection EUV lithography (US2011-0045406; JK Stowers, A. Telecky, M. Kocsis, BL Clark, DA Keszler, A. Grenville, CN Anderson, PP Naulleau, Proc. SPIE, 7969, 796915, 2011). This system has demonstrated the best performance for non-CA photoresists and possesses a speed of light approaching the requirements for viable EUV photoresists. However, hafnium metal oxide sulfate materials with peroxo complexes have several practical drawbacks. First, these materials are coated in highly corrosive sulfuric acid / hydrogen peroxide mixtures, and shelf-life stability is poor. Second, as they are composite mixtures, structural modifications to improve performance are not easy. Third, they must be developed in extremely high concentrations, such as TMAH (tetramethylammonium hydroxide) solutions of about 25 wt%.

[0009] Recently, active research has been conducted as it has become known that molecules containing tin exhibit excellent absorption of extreme ultraviolet light. In the case of organotin polymers, which are one such example, alkyl ligands dissociate due to light absorption or secondary electrons generated by it, and through cross-linking via oxo bonds with surrounding chains, negative tone patterning that cannot be removed by organic developers is possible. While such organotin polymers have demonstrated a dramatic improvement in sensitivity while maintaining resolution and line edge roughness, further improvement of the aforementioned patterning characteristics is required for commercialization.

[0010] One embodiment provides a composition for a semiconductor photoresist capable of realizing a photoresist pattern with improved coating properties and LER characteristics, while having high sensitivity and improved stability against moisture and / or atmospheric exposure.

[0011] Another embodiment provides a method for forming a pattern using the above-described semiconductor photoresist composition.

[0012] A composition for a semiconductor photoresist according to one embodiment comprises an organometallic compound represented by the following chemical formula 1 and a solvent.

[0013] [Chemical Formula 1]

[0014]

[0015] In the above chemical formula 1,

[0016] X 1 and X 2 CR each independently 5 , CR 5 R 6 , or C(=O) and,

[0017] R 1 and R 2Each is independently selected from a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C30 heteroalkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocycloalkyl 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, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, a substituted or unsubstituted C4 to C30 heteroarylalkyl group, and a substituted or unsubstituted C1 to C30 alkylcarbonyl group.

[0018] R 3 to R 6 Each is independently 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 C6 to C30 aryl group, or a combination thereof, and

[0019] n is one of the integers from 0 to 2.

[0020] A pattern forming method according to another embodiment includes the steps of: forming a film to be etched on a substrate; forming a photoresist film by applying the aforementioned semiconductor photoresist composition on the film to be etched; exposing and developing the photoresist film to form a photoresist film having a photoresist pattern; and etching the film to be etched using the photoresist pattern as an etching mask.

[0021] A composition for a semiconductor photoresist according to one embodiment can have improved storage stability, and accordingly, can provide a photoresist pattern with improved sensitivity and LER characteristics.

[0022] FIG. 1 is a cross-sectional view illustrating a method for forming a pattern using a composition for a semiconductor photoresist according to one embodiment.

[0023] <Explanation of Symbols>

[0024] 100: Substrate 102: Thin film

[0025] 104: Resist sublayer 106: Photoresist film

[0026] 106a: Unexposed area 106b: Exposed area

[0027] 108: Photoresist pattern 112: Organic film pattern

[0028] 110: Patterned mask 114: Thin film pattern

[0029]

[0030] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, in describing this description, descriptions of already known functions or configurations will be omitted to clarify the gist of this description.

[0031] To clarify the description, irrelevant details have been omitted, and the same reference numerals are used for identical or similar components throughout the specification. Additionally, the dimensions and thicknesses of each component shown in the drawings are depicted arbitrarily for convenience of explanation, and therefore the description is not necessarily limited to what is depicted.

[0032] In the drawings, thicknesses have been enlarged to clearly represent various layers and regions. Additionally, for the convenience of explanation, the thicknesses of some layers and regions have been exaggerated. When a part such as a layer, film, region, or plate is described as being "on" or "on" another part, this includes not only cases where it is "immediately on" another part, but also cases where there is another part in between.

[0033] In this description, "substitution" means that a hydrogen atom is deuterium, a halogen group, a hydroxyl group, a carboxyl group, a thiol group, a cyano group, a nitro group, -NRR' (wherein 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 C6 to C30 aromatic hydrocarbon group), -SiRR'R” (wherein 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 C6 to C30 aromatic hydrocarbon group), a C1 to C30 alkyl group, or a C1 to C10 It means being substituted with a 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, a C1 to C20 sulfide group, or a combination thereof. "Unsubstituted" means that the hydrogen atom remains as a hydrogen atom without being replaced by another substituent.

[0034] In this specification, "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.

[0035] The above alkyl group may be a C1 to C8 alkyl group. For example, the above alkyl group may be a C1 to C7 alkyl group, a C1 to C6 alkyl group, or a C1 to C5 alkyl group. For example, the C1 to C5 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, a tert-butyl group, or a 2,2-dimethylpropyl group.

[0036] In this description, "cycloalkyl group" means a monovalent cyclic aliphatic saturated hydrocarbon group unless otherwise defined.

[0037] 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.

[0038] In this specification, “aliphatic unsaturated organic group” means a hydrocarbon group comprising a bond between carbon atoms in a molecule that is a double bond, a triple bond, or a combination thereof.

[0039] The above aliphatic unsaturated organic group may be a C2 to C8 aliphatic unsaturated organic group. For example, the above aliphatic unsaturated organic group may be a C2 to C7 aliphatic unsaturated organic group, a C2 to C6 aliphatic unsaturated organic group, a C2 to C5 aliphatic unsaturated organic group, or a C2 to C4 aliphatic unsaturated organic group. For example, the C2 to C4 aliphatic unsaturated organic group may be a vinyl group, an ethanyl 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-propenyl group, a 1-methyl-1-propenyl group, a 2-propenyl group, a 2-methyl-2-propenyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 1-butainyl group, a 2-butainyl group, or a 3-butainyl group.

[0040] In this specification, "aryl group" refers to a cyclic substituent in which all elements of the substituent have p-orbitals and these p-orbitals form a conjugation, and includes monocyclic or fused-ring polycyclic (i.e., a ring sharing adjacent pairs of carbon atoms) functional groups.

[0041] In this specification, "heteroaryl group" means containing at least one heteroatom selected from the group consisting of N, O, S, P, and Si within the aryl group. Two or more heteroaryl groups may be directly connected through sigma bonds, or if the heteroaryl group comprises two or more rings, the two or more rings may be fused together. If the heteroaryl group is a fused ring, each ring may contain one to three heteroatoms.

[0042] In this specification, “alkenyl group” means an aliphatic unsaturated alkenyl group comprising one or more double bonds, which is a straight-chain or branched-chain aliphatic hydrocarbon group unless otherwise defined.

[0043] In this specification, “alkynyl group” means an aliphatic unsaturated alkynyl group comprising one or more triple bonds, which is a straight-chain or branched-chain aliphatic hydrocarbon group unless otherwise defined.

[0044] A composition for a semiconductor photoresist according to one embodiment is described below.

[0045] A composition for a semiconductor photoresist according to one embodiment of the present invention may include an organometallic compound represented by the following chemical formula 1 and a solvent.

[0046]

[0047] In the above chemical formula 1,

[0048] X 1 and X 2 CR each independently 5 , CR 5 R 6 , or C(=O) and,

[0049] R 1 and R 2Each is independently selected from a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C30 heteroalkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocycloalkyl 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, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, a substituted or unsubstituted C4 to C30 heteroarylalkyl group, and a substituted or unsubstituted C1 to C30 alkylcarbonyl group.

[0050] R 3 to R 6 Each is independently 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 C6 to C30 aryl group, or a combination thereof, and

[0051] n is one of the integers from 0 to 2.

[0052] The organometallic compound according to the present invention can have high sensitivity by including two photoreactive groups, and storage stability and delay characteristics can be further improved by forming a cyclic compound through a diol ligand.

[0053] For example, the above n can be an integer of 0 or 1.

[0054] For example, the above chemical formula 1 may be represented by at least one of the following chemical formulas 1a-1 to 1a-3 and chemical formulas 1b-1 to 1b-3.

[0055] [Chemical Formula 1a-1][Chemical Formula 1a-2][Chemical Formula 1a-3]

[0056]

[0057] [Chemical Formula 1b-1][Chemical Formula 1b-2][Chemical Formula 1b-3]

[0058]

[0059] In the above formulas 1a-1 to 1a-3, and formulas 1b-1 to 1b-3,

[0060] R 1 to R 4 ...is as defined in Paragraph 1, and

[0061] R 5a , R 5b , R 6a , and R 6b Each is independently 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 C6 to C30 aryl group, or a combination thereof.

[0062] For example, the above R 1 and R 2 Each may be independently selected from a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C2 to C20 heteroalkyl group, a substituted or unsubstituted C3 to C12 cycloalkyl group, a substituted or unsubstituted C2 to C20 heterocycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, a substituted or unsubstituted C2 to C20 heteroaryl group, a substituted or unsubstituted C7 to C20 arylalkyl group, a substituted or unsubstituted C4 to C20 heteroarylalkyl group, and a substituted or unsubstituted C1 to C20 alkylcarbonyl group.

[0063] As a specific example, the above R 1 and R 2Each is independently a substituted or unsubstituted methyl group, a substituted or unsubstituted ethyl group, a substituted or unsubstituted propyl group, a substituted or unsubstituted butyl group, a substituted or unsubstituted isopropyl group, a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted tert-pentyl group, a substituted or unsubstituted 1-methylpropyl group, a substituted or unsubstituted 1,1-dimethylpropyl group, a substituted or unsubstituted 2,2-dimethylpropyl group, a substituted or unsubstituted cyclopropyl group, a substituted or unsubstituted cyclobutyl group, a substituted or unsubstituted cyclopentyl group, a substituted or unsubstituted cyclohexyl group, a substituted or unsubstituted ethenyl group, a substituted or unsubstituted propphenyl group, a substituted or unsubstituted butenyl group, a substituted or unsubstituted ethainyl group, a substituted or unsubstituted propinyl group, a substituted or unsubstituted butainyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted tolyl group, a substituted or unsubstituted It may be a xylene group, a substituted or unsubstituted benzyl group, or a combination thereof.

[0064] For example, the above R 3 to R 6 Each may be independently a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof.

[0065] In one embodiment, the R 3 to R 6 Each may independently be hydrogen or a substituted or unsubstituted C1 to C10 alkyl group.

[0066] In a specific embodiment, the organometallic compound represented by Chemical Formula 1 may be selected from the compounds listed in Group 1 below.

[0067] [Group 1]

[0068]

[0069]

[0070]

[0071]

[0072] The organometallic compound represented by the above chemical formula 1 strongly absorbs extreme ultraviolet light at 13.5 nm, so it may have excellent sensitivity to high-energy light.

[0073] In a semiconductor photoresist composition according to one embodiment, based on 100 weight% of the composition for the semiconductor photoresist, the organometallic compound represented by Formula 1 may be included in an amount of 0.5 weight% to 30 weight%, for example, 1 weight% to 30 weight%, 1 weight% to 25 weight%, for example, 1 weight% to 20 weight%, for example, 1 weight% to 15 weight%, for example, 1 weight% to 10 weight%, for example, 1 weight% to 5 weight%, but is not limited thereto. When the organometallic compound is included in an amount within the above range, the storage stability and etch resistance of the composition for the semiconductor photoresist are improved, and the resolution characteristics are improved.

[0074] A composition for a semiconductor photoresist according to one embodiment of the present invention can provide a composition for a semiconductor photoresist having excellent sensitivity and pattern-forming properties by including the aforementioned organometallic compound.

[0075] The solvent included in the semiconductor photoresist composition according to one embodiment may be an organic solvent, and may include, for example, aromatic compounds (e.g., xylene, toluene), alcohols (e.g., 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 monomethyl ether acetate, ethyl acetate, ethyl lactate), ketones (e.g., methyl ethyl ketone, 2-heptanone), mixtures thereof, but is not limited thereto.

[0076] In one embodiment, the semiconductor photoresist composition may further include a resin in addition to the organometallic compound and solvent described above.

[0077] The resin may be a phenolic resin comprising at least one aromatic moiety listed in Group 2 below.

[0078] [Group 2]

[0079]

[0080] The above resin may have a weight-average molecular weight of 500 to 20,000.

[0081] The above resin may be included in an amount of 0.1% to 50% by weight relative to the total content of the semiconductor photoresist composition.

[0082] When the above resin is contained within the above content range, it can have excellent etch resistance and heat resistance.

[0083] Meanwhile, the composition for a semiconductor photoresist according to one embodiment preferably comprises the aforementioned organometallic compound, solvent, and resin. However, the composition for a semiconductor photoresist according to the aforementioned embodiment may additionally include additives depending on the case. Examples of the additives include surfactants, crosslinking agents, leveling agents, organic acids, quenchers, or combinations thereof.

[0084] Surfactants may be used, for example, alkylbenzenesulfonate salts, alkylpyridinium salts, polyethylene glycol, quaternary ammonium salts, or combinations thereof, but are not limited thereto.

[0085] Examples of crosslinking agents include melamine-based crosslinking agents, substituent-based crosslinking agents, acrylic-based crosslinking agents, epoxy-based crosslinking agents, or polymer-based crosslinking agents, but are not limited thereto. As a crosslinking agent having at least two crosslinking substituents, compounds such as methoxymethylated glycoluryl, butoxymethylated glycoluryl, methoxymethylated melamine, butoxymethylated melamine, methoxymethylated benzoguanamine, butoxymethylated benzoguanamine, 4-hydroxybutyl acrylate, acrylic acid, urethane acrylate, acrylic methacrylate, 1,4-butanediol diglycidyl ether, glycidol, diglycidyl 1,2-cyclohexane dicarboxylate, trimethylpropane triglycidyl ether, 1,3-bis(glycidoxypropyl)tetramethyldisiloxane, methoxymethylated urea, butoxymethylated urea, or methoxymethylated thiourea may be used.

[0086] The leveling agent is intended to improve the flatness of the coating during printing, and known leveling agents available commercially may be used.

[0087] The organic acid may be p-toluenesulfonic acid, benzenesulfonic acid, p-dodecylbenzenesulfonic acid, 1,4-naphthalenedisulfonic acid, methanesulfonic acid, sulfonium fluoride, malonic acid, citric acid, propionic acid, methacrylic acid, oxalic acid, lactic acid, glycolic acid, succinic acid, or a combination thereof, but is not limited thereto.

[0088] The quencher may be diphenyl(p-tolyl)amine, methyl diphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, or a combination thereof.

[0089] The amount of the above additives can be easily adjusted according to the desired physical properties, and may also be omitted.

[0090] In addition, the above-mentioned semiconductor photoresist composition may further use a silane coupling agent as an additive as an adhesion promoter to improve adhesion to a substrate (e.g., to improve adhesion of the semiconductor photoresist composition to a substrate). The above-mentioned silane coupling agent may be, for example, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane; or 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane; or carbon-carbon unsaturated bond containing silane compounds such as trimethoxy[3-(phenylamino)propyl]silane, but is not limited thereto.

[0091] The above composition for semiconductor photoresist can prevent pattern collapse even when forming a pattern with a high aspect ratio. Accordingly, for example, to form 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 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, for example, a fine pattern having a width of 5 nm to 10 nm, 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 of a wavelength of 5 nm to 50 nm, for example, 5 nm to It can be used in a photoresist process using light of a wavelength of 30 nm, for example, in a photoresist process using light of a wavelength of 5 nm to 20 nm. Accordingly, by using the composition for semiconductor photoresist according to one embodiment, extreme ultraviolet lithography using an EUV light source of a wavelength of about 13.5 nm can be implemented.

[0092] Meanwhile, according to another embodiment, a method for forming a pattern using the above-described semiconductor photoresist composition may be provided. As an example, the manufactured pattern may be a photoresist pattern.

[0093] In one embodiment, a method for forming a different pattern includes the steps of: forming a film to be etched on a substrate; forming a photoresist film by applying the aforementioned semiconductor photoresist composition on the film to be etched; exposing and developing the photoresist film to form a photoresist film having a photoresist pattern; and etching the film to be etched using the photoresist pattern as an etching mask.

[0094] Hereinafter, a method for forming a pattern using the semiconductor photoresist composition described above will be explained with reference to FIG. 1. FIG. 1 is a series of cross-sectional views illustrating a method for forming a pattern using a semiconductor photoresist composition according to the present invention.

[0095] Referring to FIG. 1 (a), first, an etching target is prepared. An example of the etching target may be a thin film (102) formed on a semiconductor substrate (100). The following description will be limited to cases where the etching target is a thin film (102). To remove contaminants remaining on the thin film (102), the surface of the thin film (102) is cleaned. The thin film (102) may be, for example, a silicon nitride film, a polysilicon film, or a silicon oxide film.

[0096] Next, a composition for forming a resist layer (104) is coated by applying a spin coating method to form a resist layer on the surface of the cleaned thin film (102). However, one embodiment is not necessarily limited thereto, and various known coating methods, such as spray coating, dip coating, knife edge coating, printing methods, such as inkjet printing and screen printing, may be used.

[0097] The above-mentioned resist underlayer coating process may be omitted, and the case of coating the above-mentioned resist underlayer is described below.

[0098] Subsequently, a drying and baking process is performed to form a resist lower layer film (104) on the thin film (102). The baking treatment can be performed at approximately 100 to approximately 500°C, for example, at approximately 100°C to approximately 300°C.

[0099] A resist lower layer (104) is formed between the substrate (100) and the photoresist film (106) to prevent interference with non-uniformity of the photoresist linewidth and pattern formation when irradiation rays reflected from the interface between the substrate (100) and the photoresist film (106) or from the interlayer hardmask are scattered into unintended photoresist regions.

[0100] Referring to FIG. 1(b), a photoresist film (106) is formed by coating the above-described semiconductor photoresist composition on the resist lower layer film (104). The photoresist film (106) may be in the form of a semiconductor photoresist composition that has been coated on a thin film (102) formed on a substrate (100) and then cured through a heat treatment process.

[0101] More specifically, the step of forming a pattern using a semiconductor photoresist composition may include a process of applying the above-described semiconductor photoresist composition onto a substrate (100) on which a thin film (102) is formed, such as by spin coating, slit coating, or inkjet printing, and a process of drying the applied semiconductor photoresist composition to form a photoresist film (106).

[0102] As the composition for semiconductor photoresist has already been explained in detail, a redundant explanation will be omitted.

[0103] Next, a first baking process is performed to heat the substrate (100) on which the photoresist film (106) is formed. The first baking process can be performed at a temperature of about 80°C to about 120°C.

[0104] Referring to Fig. 1 (c), the photoresist film (106) is selectively exposed using a patterned mask (110).

[0105] For example, examples of light that can be used in the above exposure process include light having short wavelengths such as the i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), and ArF excimer laser (wavelength 193 nm), as well as light having high energy wavelengths such as EUV (Extreme UltraViolet; wavelength 13.5 nm) and E-Beam (electron beam).

[0106] More specifically, the light for exposure according to one embodiment may be short-wavelength light having a wavelength range of 5 nm to 150 nm, and may be high-energy light having a wavelength such as EUV (Extreme UltraViolet; wavelength 13.5 nm) or E-Beam (electron beam).

[0107] 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 cross-linking reaction, such as condensation between organometallic compounds.

[0108] Next, a second baking process is performed on the substrate (100). The second baking process can be performed at a temperature of about 90°C to about 200°C. By performing the second baking process, the exposed area (106b) of the photoresist film (106) becomes difficult to dissolve in the developer.

[0109] In FIG. 1 (d), a photoresist pattern (108) formed by dissolving and removing the photoresist film (106a) corresponding to the unexposed area using a developer is shown. Specifically, the photoresist pattern (108) corresponding to the negative tone image is completed by dissolving and removing the photoresist film (106a) corresponding to the unexposed area using an organic solvent such as 2-heptanone.

[0110] As explained above, the developer used in the pattern forming method according to one embodiment may be an organic solvent. Examples of organic solvents used in the pattern forming method according to one embodiment include ketones such as methyl ethyl ketone, acetone, cyclohexanone, 2-heptanone, alcohols such as 4-methyl-2-propanol, 1-butanol, isopropanol, 1-propanol, methanol, esters such as propylene glycol monomethyl ether acetate, ethyl acetate, ethyl lactate, n-butyl acetate, butyrolactone, aromatic compounds such as benzene, xylene, toluene, or combinations thereof.

[0111] 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, developers that can be used to form a positive tone image may include quaternary ammonium hydroxide compositions such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, or combinations thereof.

[0112] As previously explained, a photoresist pattern (108) formed by exposure to light having wavelengths such as i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), as well as high-energy light such as EUV (Extreme UltraViolet; wavelength 13.5 nm) and E-Beam (electron beam), may have a width of 5 nm to 100 nm. For example, the photoresist pattern (108) may be formed with a width of 5 nm to 90 nm, 5 nm to 80 nm, 5 nm to 70 nm, 5 nm to 60 nm, 5 nm to 50 nm, 5 nm to 40 nm, 5 nm to 30 nm, 5 nm to 20 nm, or 5 nm to 10 nm.

[0113] Meanwhile, the photoresist pattern (108) may have a half-pitch of about 50 nm or less, for example, 40 nm or less, for example, 30 nm or less, for example, 20 nm or less, for example, 10 nm or less, and a pitch having a line width roughness of about 5 nm or less, about 3 nm or less, about 2 nm or less, about 1 nm or less.

[0114] According to another embodiment, a photoresist film manufactured by the pattern forming method described above may be provided.

[0115] Next, the photoresist pattern (108) formed on the photoresist film is used as an etching mask to etch the resist lower layer film (104). An organic film pattern (112) is formed through the etching process described above. The formed organic film pattern (112) may also have a width corresponding to the photoresist pattern (108).

[0116] Referring to FIG. 1 (e), the photoresist pattern (108) is applied as an etching mask to etch the exposed thin film (102). As a result, the thin film is formed into a thin film pattern (114).

[0117] The etching of the thin film (102) can be performed, for example, by dry etching using an etching gas, and the etching gas can be, for example, CHF3, CF4, Cl2, BCl3 and a mixture thereof.

[0118] In the previously performed exposure process, the thin film pattern (114) formed using the photoresist pattern (108) formed by the exposure process performed using an EUV light source may have a width corresponding to the photoresist pattern (108). For example, it may have a width of 5 nm to 100 nm, similar to the photoresist pattern (108). For example, the thin film pattern (114) formed by the exposure process performed using an EUV light source may have a width of 5 nm to 90 nm, 5 nm to 80 nm, 5 nm to 70 nm, 5 nm to 60 nm, 5 nm to 50 nm, 5 nm to 40 nm, 5 nm to 30 nm, 5 nm to 20 nm, similar to the photoresist pattern (108), and more specifically, may be formed with a width of 20 nm or less.

[0119] The present invention will be explained in more detail below through examples regarding the preparation of the composition for semiconductor photoresist described above. However, the technical features of the present invention are not limited by the following examples.

[0120]

[0121] (Synthesis of organometallic compounds)

[0122] Synthesis Example 1

[0123] 422.40g of Sn(iPr) and 200mL of diethylether are added to a 500mL Schrank flask and cooled to -30℃. 420.00g of SnCl is slowly added dropwise, and the temperature is raised to room temperature. The mixture is then stirred for 1 day to obtain (iPr)2SnCl2.

[0124] 3.686 g of NaH and 150 mL of diethylether are added to a 250 mL Schrank flask and cooled to -30 °C. 9.98 g of Pinacole is slowly added dropwise, then heated to room temperature and stirred for 1 hour to obtain Na2-Pinacole salt.

[0125] The flask containing the (iPr)2SnCl2 obtained above is cooled to -20°C, the Na2-Pinacole obtained above is slowly added over 30 minutes, the temperature is raised to room temperature, and then refluxed for 2 hours. After removing the byproduct NaCl using a Frit Filter, the mixture is concentrated under reduced pressure to finally obtain the compound represented by Chemical Formula 2 below.

[0126] [Chemical Formula 2]

[0127]

[0128]

[0129] Synthesis Example 2

[0130] 3.686g of NaH and 150mL of diethylether are added to a 250ml Schrank flask and cooled to -30℃. 7.44g of 2,3-butendiol is slowly added dropwise, then the temperature is raised to room temperature and stirred for 1 hour to prepare Na2-butenediol salt.

[0131] The flask containing (iPr)2SnCl2 obtained in Synthesis Example 1 above is cooled to -20°C, the Na2-butenediol obtained above is slowly added over 30 minutes, the temperature is raised to room temperature, and then refluxed for 2 hours. After removing the byproduct NaCl using a Frit Filter, the mixture is concentrated under reduced pressure to finally obtain the compound represented by Chemical Formula 3 below.

[0132] [Chemical Formula 3]

[0133]

[0134]

[0135] Synthesis Example 3

[0136] 3.686 g of NaH and 150 mL of diethylether were added to a 250 mL Schrank flask, and then cooled to -30 °C. 7.61 g of oxalic acid was slowly added dropwise, then the temperature was raised to room temperature and stirred for 1 hour to obtain Na2-oxalate salt.

[0137] The flask containing the (iPr)2SnCl2 obtained in Synthesis Example 1 above is cooled to -20°C, the Na2-Oxalate obtained above is slowly added over 30 minutes, the temperature is raised to room temperature, and then refluxed for 2 hours. After removing the byproduct NaCl using a Frit Filter, the mixture is concentrated under reduced pressure to finally obtain the compound represented by Chemical Formula 4 below.

[0138] [Chemical Formula 4]

[0139]

[0140]

[0141] Comparative Synthesis Example 1

[0142] Add 340.7g of t-butylSnPh and 300g of propionic acid to a 250ml two-necked round-bottom flask and heat under reflux for 24 hours.

[0143] Unreacted propionic acid is removed under reduced pressure to obtain a compound represented by the following chemical formula 5.

[0144] [Chemical Formula 5]

[0145]

[0146]

[0147] Comparative Synthesis Example 2

[0148] 30 ml of anhydrous pentane is added to 10 g of t-AmylSnCl3 and the temperature is maintained at 0°C, then 7.4 g of diethylamine and 6.1 g of ethanol are added and stirred at room temperature for 1 hour. When the reaction is finished, the mixture is filtered, concentrated, and vacuum dried to obtain a compound represented by the following chemical formula 6.

[0149] [Chemical Formula 6]

[0150]

[0151]

[0152] (Preparation of a composition for semiconductor photoresist)

[0153] Examples 1 to 3, Comparative Examples 1 and 2

[0154] The organometallic compounds obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples 1 and 2 were each dissolved in PGMEA (propylene glycol monomethyl ether acetate) at 3 wt% and filtered through a 0.1 μm PTFE syringe filter to prepare a photoresist composition.

[0155]

[0156] Evaluation 1: Sensitivity and Line Edge Roughness (LER) Evaluation

[0157] The photoresist compositions according to the above examples and comparative examples are each spin-coated at 1500 rpm for 30 seconds on a 200 mm circular silicon wafer on which the surface is deposited with HMDS, and then baked at 110 ℃ for 60 seconds (post-apply bake, PAB) and left at room temperature (23±2℃) for 30 seconds.

[0158] Subsequently, a linear array of 50 circular pads with a diameter of 500 μm was projected onto a wafer coated with the photoresist composition using EUV light (Lawrence Berkeley National Laboratory Micro Exposure Tool, MET). The pad exposure time was adjusted so that an increased EUV dose was applied to each pad.

[0159] Subsequently, the resist and substrate were exposed on a hot plate at 160°C for 120 seconds and then fired. The fired film was developed with PGMEA solvent to form a negative tone image. Finally, the process was terminated by performing hot plate firing at 150°C for 2 minutes.

[0160] The residual resist thickness of the exposed pad was measured using an ellipsometer. The remaining thickness was measured for each exposure amount and graphed as a function of the exposure amount to measure sensitivity, and the LER was measured from the FE-SEM image, with the results shown in Table 1.

[0161]

[0162] Evaluation 2: Delay Characteristic Evaluation

[0163] The photoresist composition according to the above example and comparative example is spin-coated for 30 seconds at 1500 rpm on a 200 mm circular silicon wafer on which the surface is deposited with HMDS, and then baked at 100°C to 120°C for 60 seconds (post-apply bake, PAB) and left at room temperature for 10 minutes (process delay time).

[0164] Subsequently, a linear array of 50 circular pads with a diameter of 500 μm was projected onto a wafer coated with the photoresist composition using EUV light (Lawrence Berkeley National Laboratory Micro Exposure Tool, MET). The pad exposure time was adjusted so that an increased EUV dose was applied to each pad.

[0165] Subsequently, the resist and substrate were exposed on a hot plate at 180°C for 120 seconds and then fired. The fired film was developed with PGMEA solvent to form a negative tone image, and then the process was finally terminated by performing hot plate firing at 150°C for 2 minutes.

[0166] The resist linewidth formed by exposure with the same Dose (Energy) was measured using CD-SEM. The linewidth (CD) values ​​of the resist patterns formed according to process delay times (10 min, 20 min, 30 min, 40 min, 50 min, 60 min) were checked, and the delay characteristics according to Equation 1 below were calculated, and the results are shown in Table 1.

[0167] [Equation 1]

[0168] Delay Characteristic = {Maximum CD value among patterns formed at 10-minute intervals for 60 minutes after PAB / CD value of patterns formed without idle} * 100

[0169] [metewand]

[0170] - ○: △CD greater than 2% and less than or equal to 7%

[0171] - △: △CD greater than 7% and less than or equal to 15%

[0172] - X: △CD exceeds 15%

[0173]

[0174] Evaluation 3: Storage Stability Evaluation

[0175] For the organometallic compounds used in Examples 1 to 3 and Comparative Examples 1 and 2, storage stability was evaluated according to the following criteria and is shown in Table 1 below.

[0176] [Storage Stability]

[0177] When semiconductor photoresist compositions according to Examples 1 to 3 and Comparative Examples 1 and 2 were left for a specific period under room temperature conditions, the degree of precipitation was observed visually and evaluated according to the storage criteria below.

[0178] ※ Evaluation Criteria

[0179] - ○: Can be stored for 3 months or more

[0180] - △: Can be stored for at least 1 week for less than 3 months

[0181] - X: Can be stored for less than 1 week

[0182] LER (nm) sensitivity (mJ / cm²) 2 Storage Stability Delay Characteristics Example 1 2.355△○ Example 22.652△△ Example 3 2.957○○ Comparative Example 13.360△X Comparative Example 23.263X△

[0183] From the results of Table 1, it can be confirmed that the patterns formed using the semiconductor photoresist compositions according to Examples 1 to 3 exhibit superior levels of LER, sensitivity, and storage stability, as well as significantly improved coating performance compared to Comparative Examples 1 and 2.

[0184]

[0185] Although specific embodiments of the present invention have been described and illustrated above, it is obvious to those skilled in the art that the present invention is not limited to the described embodiments and can be modified and varied in various ways without departing from the spirit and scope of the present invention. Accordingly, such modifications or variations should not be understood individually from the technical spirit or perspective of the present invention, and the modified embodiments should be considered to fall within the scope of the claims of the present invention.

Claims

1. An organometallic compound represented by the following chemical formula 1; and menstruum A composition for semiconductor photoresist comprising: [Chemical Formula 1] In the above chemical formula 1, X 1 and X 2 CR each independently 5 , CR 5 R 6 , or C(=O) and, R 1 and R 2 Each is independently selected from a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C2 to C30 heteroalkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, a substituted or unsubstituted C2 to C30 heterocycloalkyl 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, a substituted or unsubstituted C2 to C30 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, a substituted or unsubstituted C4 to C30 heteroarylalkyl group, and a substituted or unsubstituted C1 to C30 alkylcarbonyl group. R 3 to R 6 Each is independently 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 C6 to C30 aryl group, or a combination thereof, and n is one of the integers from 0 to 2.

2. In Paragraph 1, A composition for a semiconductor photoresist, wherein n is an integer of 0 or 1.

3. In Paragraph 1, A composition for a semiconductor photoresist, wherein the above chemical formula 1 is represented by at least one of the following chemical formulas 1a-1 to 1a-3 and chemical formulas 1b-1 to 1b-3: [Chemical Formula 1a-1][Chemical Formula 1a-2][Chemical Formula 1a-3] [Chemical Formula 1b-1][Chemical Formula 1b-2][Chemical Formula 1b-3] In the above formulas 1a-1 to 1a-3, and formulas 1b-1 to 1b-3, R 1 to R 4 ...is as defined in Paragraph 1, and R 5a , R 5b , R 6a , and R 6b Each is independently 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 C6 to C30 aryl group, or a combination thereof.

4. In Paragraph 1, The above R 1 and R 2 A composition for a semiconductor photoresist, wherein each is independently selected from a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C2 to C20 heteroalkyl group, a substituted or unsubstituted C3 to C12 cycloalkyl group, a substituted or unsubstituted C2 to C20 heterocycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, a substituted or unsubstituted C2 to C20 heteroaryl group, a substituted or unsubstituted C7 to C20 arylalkyl group, a substituted or unsubstituted C4 to C20 heteroarylalkyl group, and a substituted or unsubstituted C1 to C20 alkylcarbonyl group.

5. In Paragraph 1, The above R 1 and R 2 Each is independently a substituted or unsubstituted methyl group, a substituted or unsubstituted ethyl group, a substituted or unsubstituted propyl group, a substituted or unsubstituted butyl group, a substituted or unsubstituted isopropyl group, a substituted or unsubstituted tert-butyl group, a substituted or unsubstituted tert-pentyl group, a substituted or unsubstituted 1-methylpropyl group, a substituted or unsubstituted 1,1-dimethylpropyl group, a substituted or unsubstituted 2,2-dimethylpropyl group, a substituted or unsubstituted cyclopropyl group, a substituted or unsubstituted cyclobutyl group, a substituted or unsubstituted cyclopentyl group, a substituted or unsubstituted cyclohexyl group, a substituted or unsubstituted ethenyl group, a substituted or unsubstituted propphenyl group, a substituted or unsubstituted butenyl group, a substituted or unsubstituted ethainyl group, a substituted or unsubstituted propinyl group, a substituted or unsubstituted butainyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted tolyl group, a substituted or unsubstituted A composition for semiconductor photoresist comprising a xylene group, a substituted or unsubstituted benzyl group, or a combination thereof.

6. In Paragraph 1, The above R 3 to R 6 A composition for a semiconductor photoresist, wherein each is independently a substituted or unsubstituted C1 to C10 alkyl group, a substituted or unsubstituted C3 to C10 cycloalkyl group, a substituted or unsubstituted C2 to C10 alkenyl group, a substituted or unsubstituted C2 to C10 alkynyl group, a substituted or unsubstituted C6 to C20 aryl group, or a combination thereof.

7. In Paragraph 1, The above R 3 to R 6 A composition for a semiconductor photoresist, wherein each is independently hydrogen or a substituted or unsubstituted C1 to C10 alkyl group.

8. In Paragraph 1, A composition for a semiconductor photoresist, wherein the organometallic compound represented by the above chemical formula 1 is one selected from the compounds listed in Group 1 below: [Group 1] .

9. In Paragraph 1, A semiconductor photoresist composition comprising an organometallic compound represented by the above chemical formula 1 in an amount of 0.5% to 30% by weight based on 100% by weight of the semiconductor photoresist composition.

10. In Paragraph 1, A composition for a semiconductor photoresist further comprising a surfactant, a crosslinking agent, a leveling agent, an organic acid, a quencher, or other additives in combination thereof.

11. A step of forming an etching target film on a substrate; A step of forming a photoresist film by applying a composition for a semiconductor photoresist according to any one of claims 1 to 10 onto the above-mentioned etching target film; A step of exposing and developing the above photoresist film to form a photoresist film having a photoresist pattern formed thereon; and A pattern forming method comprising the step of etching the etching target film using the above photoresist pattern as an etching mask.

12. In Paragraph 11, The step of forming the above photoresist pattern is a pattern forming method using light with a wavelength of 5 nm to 150 nm.

13. In Paragraph 1, The above photoresist pattern is a pattern forming method having a width of 5 nm to 100 nm.

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