Semiconductor photoresist composition and method of forming patterns using the same

Abstract

To provide a semiconductor photoresist composition having excellent sensitivity and line edge roughness (LER) characteristics, and improved resolution, and a method of forming patterns using the semiconductor photoresist composition.SOLUTION: The present invention relates to a semiconductor photoresist composition including: a Sn-containing organometallic compound; a carboxylic acid compound represented by Chemical Formula 1; and a solvent, and a method of forming patterns using the semiconductor photoresist composition.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] This description relates to a composition for a semiconductor photoresist and a pattern forming method using the same.

Background Art

[0002] As one of the elemental technologies for manufacturing next-generation semiconductor devices, EUV (extreme ultraviolet light) lithography has attracted attention. EUV lithography is a pattern forming technology that uses EUV light with a wavelength of 13.5 nm as an exposure light source. According to EUV lithography, it has been demonstrated that extremely fine patterns (for example, 20 nm or less) can be formed in the exposure process of the semiconductor device manufacturing process.

[0003] The realization of extreme ultraviolet (EUV) lithography requires the development of compatible photoresists that can be performed with spatial resolutions of 16 nm or less. Currently, traditional chemically amplified (CA) photoresists are striving to meet the specifications for resolution, photo speed, and feature roughness, line edge roughness (or LER) for next-generation devices.

[0004] The intrinsic image blur resulting from acid catalyzed reactions that occur in these polymeric photoresists limits resolution at small feature sizes, which has been known for a long time in e-beam lithography. Chemically amplified (CA) photoresists are designed for high sensitivity, but their typical elemental makeup reduces the absorbance of the photoresist at a wavelength of 13.5 nm, and as a result, they can be more difficult under EUV exposure, in part because of the reduced sensitivity.

[0005] CA photoresists can be troubled by roughness problems at small feature sizes, and experimentally, it has been shown that as the photospeed decreases, the line edge roughness (LER) increases, in part due to the nature of the acid catalyzed process. Due to the drawbacks and problems of CA photoresists, there is a need in the semiconductor industry for a new type of high-performance photoresist.

[0006] To overcome the shortcomings of the chemically amplified organic photosensitive compositions described above, inorganic photosensitive compositions have been studied. In the case of inorganic photosensitive compositions, they are mainly used for negative tone patterning that has resistance to removal by a developer composition through chemical modification by a non-chemically amplified mechanism. In the case of inorganic compositions, since they contain inorganic elements with a high EUV absorption rate compared to hydrocarbons, sensitivity can be ensured even with a non-chemically amplified mechanism, and they are said to be less sensitive to the stochastic effect and also have less line edge roughness and fewer defects.

[0007] Inorganic photoresists based on peroxopolyacids of tungsten, and tungsten mixed with niobium, titanium, and / or tantalum have been reported for use as 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 have been effective as deep ultraviolet (deep UV), x-ray, and electron beam sources for patterning large features in bilayer configurations. More recently, when using cationic hafnium metal oxide sulfate (HfSOx) materials with peroxo complexing agents to image 15 nm half-pitch (HP) by projection EUV lithography, impressive performance has been shown (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 top performance of non-CA photoresist and has a photospeed approaching the requirements for a viable EUV photoresist. However, hafnium metal oxide sulfate materials with peroxo complexing agents have several practical drawbacks. First, this material is coated with a highly corrosive sulfuric acid / hydrogen peroxide mixture and has poor shelf-life stability. Second, it is not easy to make structural changes for performance improvement as a composite mixture. Third, it must be developed with a very high concentration of about 25 wt% tetramethylammonium hydroxide (TMAH) solution or the like.

[0009] In recent years, molecules containing tin are known to have excellent extreme ultraviolet absorption and are being actively studied. In the case of organotin polymers, one of them, the alkyl ligand dissociates due to light absorption or secondary electrons generated thereby, and negative tone patterning that cannot be removed with an organic developer is possible by crosslinking with an oxo bond to the peripheral chain. Such organotin polymers have shown a dramatic improvement in sensitivity while maintaining resolution and line edge roughness. However, for commercialization, further improvement of the patterning characteristics is required.

Summary of the Invention

Problems to be Solved by the Invention

[0010] One embodiment provides an excellent semiconductor photoresist composition having excellent sensitivity and line edge roughness (LER) characteristics and improved resolution.

[0011] Another embodiment provides a patterning method using the semiconductor photoresist composition.

[0012] The semiconductor photoresist composition according to one embodiment includes a Sn-containing organometallic compound; a carboxylic acid compound represented by the following Chemical Formula 1, and a solvent.

Chem.

[0013] The patterning method according to another embodiment includes a step of forming an etching target film on a substrate, a step of applying the semiconductor photoresist composition described above on the etching target film to form a photoresist film, a step of patterning the photoresist film to form a photoresist pattern, and a step of etching the etching target film using the photoresist pattern as an etching mask.

[0014] A composition for a semiconductor photoresist according to an embodiment can achieve excellent sensitivity, excellent LER, and excellent resolution.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0016] Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail as follows. However, in describing this description, descriptions of functions or configurations that are already known will be omitted in order to clarify the gist of this description.

[0017] To clearly explain this description, parts not related to the explanation are omitted, and the same or similar components throughout the specification are given the same reference numerals. Also, the size and thickness of each configuration shown in the drawings are arbitrarily shown for convenience of explanation, and this description is not necessarily limited to what is shown in the drawings.

[0018] In the drawings, for the purpose of clearly showing a plurality of layers and regions, the thickness is shown enlarged. Also, in the drawings, for the sake of convenience in explanation, the thicknesses of some layers and regions are shown exaggerated. When a part such as a layer, film, region, or plate is “on” or “above” another part, this includes not only the case where it is directly above the other part, but also the case where there are other parts in between.

[0019] As used herein, “substituted” means that a hydrogen atom is replaced by deuterium, a halogen group, a hydroxy group, a thiol group, a cyano group, a nitro group, -NRR’ (wherein R and R’ are each independently hydrogen, a substituted or unsubstituted C1-C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3-C30 saturated or unsaturated cycloaliphatic hydrocarbon group, or a substituted or unsubstituted C6-C30 aromatic hydrocarbon group), -SiRR’R” (wherein R, R’, and R” are each independently hydrogen, a substituted or unsubstituted C1-C30 saturated or unsaturated aliphatic hydrocarbon group, a substituted or unsubstituted C3-C30 saturated or unsaturated cycloaliphatic hydrocarbon group, or a substituted or unsubstituted C6-C30 aromatic hydrocarbon group), a C1-C30 alkyl group, a C1-C10 haloalkyl group, a C1-C10 alkylsilyl group, a C3-C30 cycloalkyl group, a C6-C30 aryl group, a C1-C20 alkoxy group, a C1-C20 sulfide group, or a combination thereof. “Unsubstituted” means that the hydrogen atom is not replaced by another substituent and remains as a hydrogen atom.

[0020] As used herein, the term “alkyl group” means a straight-chain or branched-chain aliphatic hydrocarbon group, unless otherwise defined. The alkyl group may be a “saturated alkyl group” having no double bonds or triple bonds.

[0021] The alkyl group may be a C1-C8 alkyl group. For example, the alkyl group may be a C1-C7 alkyl group, a C1-C6 alkyl group, or a C1-C5 alkyl group. For example, the C1-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, or a tert-butyl group, or a 2,2-dimethylpropyl group.

[0022] In this description, the "cycloalkyl group" means a monovalent cyclic aliphatic saturated hydrocarbon group unless otherwise defined.

[0023] The cycloalkyl group may be a C3-C8 cycloalkyl group, for example, a C3-C7 cycloalkyl group, a C3-C6 cycloalkyl group, a C3-C5 cycloalkyl group, or a C3-C4 cycloalkyl group. For example, the cycloalkyl group may be a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and is not limited thereto.

[0024] In this specification, the "aliphatic unsaturated organic group" means a hydrocarbon group in which the bond between carbon atoms in the molecule contains a double bond, a triple bond, or a combination of these bonds.

[0025] The aliphatic unsaturated organic group may be a C2-C8 aliphatic unsaturated organic group. For example, the aliphatic unsaturated organic group may be a C2-C7 aliphatic unsaturated organic group, a C2-C6 aliphatic unsaturated organic group, a C2-C5 aliphatic unsaturated organic group, or a C2-C4 aliphatic unsaturated organic group. For example, the C2-C4 aliphatic unsaturated organic group may be a vinyl group, an ethynyl group, an aryl 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, a 1-methyl-1-propynyl group, a 2-propynyl group, a 2-methyl-2-propynyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a 1-butynyl group, a 2-butynyl group, or a 3-butynyl group.

[0026] As used herein, the term "aryl group" means a substituent in which all elements of the cyclic substituent have p-orbitals and these p-orbitals form conjugation, and includes monocyclic or fused polycyclic (i.e., rings sharing adjacent pairs of carbon atoms) functional groups.

[0027] As used herein, the term "heteroaryl group" means that the aryl group contains at least one heteroatom selected from the group consisting of N, O, S, P, and Si. Two or more heteroaryl groups can be directly linked via a sigma bond, or when the heteroaryl group contains two or more rings, the two or more rings can be fused to each other. When the heteroaryl group is a fused ring, each ring can contain 1 to 3 of the heteroatoms.

[0028] As used herein, the term "alkenyl group" means a straight-chain or branched-chain aliphatic hydrocarbon group, which is an aliphatic unsaturated alkenyl group containing one or more double bonds, unless otherwise defined.

[0029] As used herein, the term "alkynyl group" means a straight-chain or branched-chain aliphatic hydrocarbon group, which is an aliphatic unsaturated alkynyl group containing one or more triple bonds, unless otherwise defined.

[0030] Hereinafter, a composition for a semiconductor photoresist according to an embodiment will be described.

[0031] A composition for a semiconductor photoresist according to an embodiment of the present invention can include a Sn-containing organometallic compound, a carboxylic acid compound represented by the following Chemical Formula 1, and a solvent.

Chemical formula

[0032] By including the carboxylic acid compound represented by Chemical Formula 1, that is, the carboxylic acid compound containing a polycyclic aliphatic hydrocarbon group, the semiconductor photoresist composition can improve sensitivity and LER and achieve excellent resolution.

[0033] In the present invention, the "polycyclic aliphatic hydrocarbon group" means a fused ring structure in which two or more rings share one or more pairs of carbon atoms. Specifically, it can mean a bridged polycyclic aliphatic hydrocarbon group having 5 to 50 carbon atoms.

[0034] Examples of the polycyclic aliphatic hydrocarbon group include, but are not limited to, adamantane, norbornane, isobornane, tricyclodecane, tetracyclododecane, and the like.

[0035] A may be a substituted or unsubstituted adamantyl group, a substituted or unsubstituted norbornyl group, a substituted or unsubstituted isobornyl group, a substituted or unsubstituted tricyclodecanyl group, a substituted or unsubstituted tetracyclododecanyl group, or a combination thereof.

[0036] As a specific example, the carboxylic acid compound represented by Chemical Formula 1 may be one of the compounds listed in Group 1 below.

Chemical formula

[0037] For example, the carboxylic acid compound represented by Chemical Formula 1 can be contained in an amount of 0.01 to 5% by weight or 0.05 to 3% by weight based on 100% by weight of the semiconductor photoresist composition.

[0038] The Sn-containing organometallic compound can be contained in an amount of 0.5% by weight to 30% by weight based on 100% by weight of the semiconductor photoresist composition.

[0039] By including the Sn-containing organometallic compound and the carboxylic acid compound represented by the chemical formula 1 in the content range in the semiconductor photoresist composition according to one embodiment, the sensitivity of the photoresist can be improved.

[0040] The semiconductor photoresist composition according to one embodiment can contain the Sn-containing organometallic compound and the carboxylic acid compound represented by the chemical formula 1 in a weight ratio of 99:1 to 80:20. For example, the semiconductor photoresist composition can contain the Sn-containing organometallic compound and the carboxylic acid compound represented by the chemical formula 1 in a weight ratio of 95:5 to 85:15.

[0041] When the weight ratio of the Sn-containing organometallic compound and the carboxylic acid compound represented by the chemical formula 1 satisfies the above range, a semiconductor photoresist composition having excellent sensitivity can be provided.

[0042] The Sn-containing organometallic compound can contain at least one of an organic oxy group and an organic carbonyloxy group.

[0043] The organometallic compound is represented by the following chemical formula 2.

Chemical formula

[0044] Said R 3 ~R 5 At least one of which is alkoxo and aryloxo (-OR b , where R b is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), and carboxyl group (-O(C=O)R c , R c can be selected from hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof).

[0045] On the other hand, the compound represented by the chemical formula 2 can exhibit excellent limit resolution in the pattern formed by using the semiconductor photoresist composition containing it by containing -OR b or -OC(=O)R c .

[0046] Also, the ligand of -OR b or -OC(=O)R c can determine the solubility of the compound represented by the chemical formula 2 in the solvent.

[0047] Said R 2is a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 aliphatic unsaturated organic group containing one or more double bonds or triple bonds, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C4-C20 heteroaryl group, a carbonyl group, an ethoxy group, a propoxy group, or a combination thereof, R b is a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 alkenyl group, a substituted or unsubstituted C2-C8 alkynyl group, a substituted or unsubstituted C6-C20 aryl group, or a combination thereof, R c may be hydrogen, a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 alkenyl group, a substituted or unsubstituted C2-C8 alkynyl group, a substituted or unsubstituted C6-C20 aryl group, or a combination thereof.

[0048] Said R 2 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, a formyl group, an acetyl group, a propanoyl group, a butanoyl group, a pentanoyl group, an ethoxy group, a propoxy group, or a combination thereof, R b is 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 cIt may be hydrogen, 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.

[0049] Further, the Sn-containing organometallic compound is represented by the following Chemical Formula 3 or Chemical Formula 4.

Chemical Formula

Chemical Formula

[0050] The solvent contained in the composition for a semiconductor photoresist according to one embodiment may be an organic solvent. As an example, it may include 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, etc., but is not limited thereto.

[0051] The composition for a semiconductor resist according to one embodiment may further include a resin in addition to the Sn-containing organometallic compound, the carboxylic acid compound represented by Chemical Formula 1, and the solvent.

[0052] The resin may be a phenolic resin containing at least one aromatic moiety listed in Group 2 below.

Chemical formula

[0053] The resin may be contained in an amount of 0.1% by weight to 50% by weight based on the total content of the composition for a semiconductor photoresist.

[0054] When the resin is contained within the above content range, it can have excellent etching resistance and heat resistance.

[0055] On the other hand, it is preferable that the composition for semiconductor photoresist consists of the Sn-containing organometallic compound, the carboxylic acid compound represented by Chemical Formula 1, a solvent, and a resin as described above.

[0056] The composition for semiconductor photoresist according to the above-described embodiments may optionally further contain an additive. Examples of the additive may include a surfactant, a crosslinking agent, a leveling agent, an organic acid, a quencher, or a combination thereof.

[0057] As the surfactant, for example, alkylbenzene sulfonate, alkylpyridinium salt, polyethylene glycol, quaternary ammonium salt, or a combination thereof can be used, but is not limited thereto.

[0058] As the crosslinking agent, for example, melamine-based crosslinking agent, substituted urea-based crosslinking agent, acrylic-based crosslinking agent, epoxy-based crosslinking agent, or polymer-based crosslinking agent can be mentioned, but is not limited thereto. As the crosslinking agent having at least two crosslinking-forming substituents, for example, methoxymethylated glycolyl, butoxymethylated glycolyl, 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-cyclohexanedicarboxylate, trimethylpropane triglycidyl ether, 1,3-bis(glycidoxypropyl)tetramethyldisiloxane acid, methoxymethylated urea, butoxymethylated urea, or methoxymethylated thiourea and other compounds can be used.

[0059] The leveling agent is for improving the flatness of the coating during printing, and a known leveling agent available by a commercial method can be used.

[0060] The organic acid may be, but is not limited to, p-toluenesulfonic acid, benzenesulfonic acid, p-dodecylbenzenesulfonic acid, 1,4-naphthalenedisulfonic acid, methanesulfonic acid, fluorinated sulfonate, malonic acid, citric acid, propionic acid, methacrylic acid, oxalic acid, lactic acid, glycolic acid, succinic acid, or a combination thereof.

[0061] The inhibitor may be, but is not limited to, diphenyl(p-toluyl)amine, methyldiphenylamine, triphenylamine, phenylenediamine, naphthylamine, diaminonaphthalene, or a combination thereof.

[0062] In one embodiment, an acid compound different from the carboxylic acid compound represented by Chemical Formula 1 can be mixed in the composition for a semiconductor photoresist according to the present invention. Examples of the mixable acid compounds include organic acids, sulfonic acids, phosphonic acids, and the like.

[0063] The usage amounts of these additives can be easily adjusted according to desired physical properties and can also be omitted.

[0064] In addition, for improving the adhesion to a substrate (for example, for improving the adhesion between the composition for a semiconductor photoresist and the substrate), a silane coupling agent can be further used as an additive as an adhesion promoter in the composition for a semiconductor photoresist. Examples of the silane coupling agent include carbon-carbon unsaturated bond-containing silane compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltris(β-methoxyethoxy)silane; or 3-methacryloxypropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane; trimethoxy[3-(phenylamino)propyl]silane, etc., but are not limited thereto.

[0065] The semiconductor photoresist composition may not cause pattern collapse even when forming a pattern having a high aspect ratio. Therefore, for example, in order 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, it can be used in a photoresist process using light with a wavelength of 5 nm to 150 nm, for example, a photoresist process using light with a wavelength of 5 nm to 100 nm, for example, a photoresist process using light with 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 process using light with a wavelength of 5 to 20 nm. Therefore, by using the semiconductor photoresist composition according to one embodiment, extreme ultraviolet lithography using an EUV light source with a wavelength of about 13.5 nm can be realized.

[0066] On the other hand, according to another embodiment, a method of forming a pattern using the above-described semiconductor photoresist composition can be provided. As an example, the manufactured pattern may be a photoresist pattern.

[0067] Another pattern formation method according to one embodiment includes the steps of forming an etching target film on a substrate, applying the above-described semiconductor photoresist composition on the etching target film to form a photoresist film, patterning the photoresist film to form a photoresist pattern, and etching the etching target film using the photoresist pattern as an etching mask.

[0068] Hereinafter, a method for forming a pattern using the above-described composition for a semiconductor photoresist will be described with reference to FIGS. 1 to 5. FIGS. 1 to 5 are cross-sectional views for explaining a pattern formation method using the composition for a semiconductor photoresist according to the present invention.

[0069] Referring to FIG. 1, a priority etching target is provided. Examples of the etching target include a thin film 102 formed on a semiconductor substrate 100. Hereinafter, the description will be made only when the etching target is the thin film 102. To remove contaminants and the like 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.

[0070] 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 to this, and various known coating methods, for example, spray coating, dip coating, knife edge coating, printing methods, for example, inkjet printing and screen printing, etc. can also be used.

[0071] The resist underlayer film coating process can be omitted, and hereinafter, the case of coating the resist underlayer film will be described.

[0072] Thereafter, a drying and baking process is performed to form a resist underlayer film 104 on the thin film 102. The baking treatment is performed at about 100 to about 500 ° C, and can be performed, for example, at about 100 ° C to about 300 ° C.

[0073] The resist underlayer film 104 is formed between the substrate 100 and the photoresist film 106, and can prevent the unevenness of the photoresist linewidth and the pattern formation property from being hindered when the irradiation line reflected from the interface between the substrate 100 and the photoresist film 106 or the interlayer hardmask is scattered into an unintended photoresist region.

[0074] Referring to FIG. 2, the above-described composition for a semiconductor photoresist is coated on the resist underlayer film 104 to form a photoresist film 106. The photoresist film 106 can be in a form cured through a heat treatment process after the above-described composition for a semiconductor photoresist is coated on the thin film 102 formed on the substrate 100.

[0075] More specifically, the step of forming a pattern using the composition for a semiconductor photoresist can include a process of applying the above-described composition for a semiconductor photoresist on the substrate 100 on which the thin film 102 is formed by spin coating, slit coating, inkjet printing, etc., and a process of drying the applied composition for a semiconductor photoresist to form a photoresist film 106.

[0076] Since the composition for a semiconductor photoresist has already been described in detail, redundant descriptions are omitted.

[0077] Subsequently, a first baking process of heating the substrate 100 on which the photoresist film 106 is formed is performed. The first baking process can be performed at a temperature of about 80°C to about 120°C.

[0078] Referring to FIG. 3, the photoresist film 106 is selectively exposed using the patterned mask 110.

[0079] As an example, examples of the light that can be used in the exposure process include not only light having a short wavelength such as activation irradiation i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), etc., but also light having a high energy wavelength such as EUV (Extreme ultraviolet; wavelength 13.5 nm), E-Beam (electron beam), etc.

[0080] More specifically, the exposure light according to an embodiment may be short-wavelength light having a wavelength range of 5 nm to 150 nm, or may be light having a high energy wavelength such as EUV (Extreme ultraviolet; wavelength 13.5 nm), E-Beam (electron beam), etc.

[0081] The exposed region 106a of the photoresist film 106 becomes different in solubility from the unexposed region 106b of the photoresist film 106 by forming a polymer by a crosslinking reaction such as condensation between organometallic compounds.

[0082] Subsequently, 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 region 106a of the photoresist film 106 becomes difficult to dissolve in the developer.

[0083] FIG. 4 shows a photoresist pattern 108 formed by dissolving and removing the photoresist film 106b corresponding to the unexposed region using a developer. Specifically, after dissolving the photoresist film 106b corresponding to the unexposed region using an organic solvent such as 2-heptanone and then removing it, the photoresist pattern 108 corresponding to the negative tone image is completed.

[0084] As described above, the developer used in the pattern formation method according to an embodiment can be an organic solvent. Examples of the organic solvent used in the pattern formation method according to an embodiment include ketones such as methyl ethyl ketone, acetone, cyclohexanone, and 2-heptanone; alcohols such as 4-methyl-2-propanol, 1-butanol, isopropanol, 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 combinations thereof.

[0085] However, the photoresist pattern according to an embodiment is not necessarily limited to being formed as a negative-tone image, and it can also be formed to have a positive-tone image. In this case, examples of the developer that can be used for forming a positive-tone image include quaternary ammonium hydroxide compositions such as tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, or combinations thereof.

[0086] As described above, the photoresist pattern 108 formed by exposure with light having a wavelength such as i-line (wavelength 365 nm), KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), etc., as well as light having high energy such as EUV (Extreme ultraviolet; wavelength 13.5 nm), E-Beam (electron beam), etc., can have a width with a thickness of 5 nm to 100 nm. As an example, the photoresist pattern 108 can be formed with a width having a thickness 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.

[0087] On the one hand, the photoresist pattern 108 can 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, 15 nm or less, and a pitch with a line width roughness of about 10 nm or less, about 5 nm or less, about 3 nm or less, about 2 nm or less.

[0088] Subsequently, using the photoresist pattern 108 as an etching mask, the resist underlayer film 104 is etched. Through such an etching process, an organic film pattern 112 is formed. The formed organic film pattern 112 can have a width corresponding to that of the photoresist pattern 108.

[0089] Referring to FIG. 5, 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.

[0090] 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 mixed gas thereof.

[0091] In the exposure process performed previously, the thin film pattern 114 formed using the photoresist pattern 108 formed by the exposure process using an EUV light source can have a width corresponding to that of the photoresist pattern 108. As an example, similar to the photoresist pattern 108, it can have a width of 5 nm to 100 nm. For example, the thin film pattern 114 formed by the exposure process using an EUV light source can 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, it can be formed with a width of 20 nm or less.

Example

[0092] Hereinafter, the present invention will be described in more detail through examples related to the production of the above-described composition for semiconductor photoresist. However, the technical features of the present invention are not limited by the following examples.

[0093] Synthesis of Organometallic Compounds Synthesis Example 1 40.7 g of t-butylSnPh3 and 300 g of propionic acid are placed in a 250 ml two-necked round-bottom flask and heated under reflux for 24 hours.

[0094] Unreacted propionic acid is removed under reduced pressure to obtain a compound represented by the following Chemical Formula 5.

Chemical Formula

[0095] Synthesis Example 2 30 ml of anhydrous pentane is added to 10 g of t-AmylSnCl3, the temperature is kept at 0 °C, 7.4 g of diethylamine and 6.1 g of ethanol are added, and the mixture is stirred at room temperature for 1 hour. After the reaction is completed, it is filtered, concentrated and vacuum dried to obtain a compound represented by the following Chemical Formula 6.

Chemical Formula

[0096] Synthesis Example 3 After dissolving 10 g of Dibutyltin dichloride in 30 mL of ether, 70 mL of 1M aqueous sodium hydroxide (NaOH) solution is added and stirred for 1 hour. After stirring, the resulting solid is filtered, washed three times with 25 mL of deionized water, and then dried under reduced pressure at 100 °C to obtain an organometallic compound represented by the following Chemical Formula 7 with a weight average molecular weight of 1,500.

Chemical Formula

[0097] (Production of Composition for Semiconductor Photoresist) Examples 1 to 12 and Comparative Examples 1 to 9 The compounds represented by Chemical Formulas 5 to 7 obtained in Synthesis Examples 1 to 3 and the carboxylic acid compound represented by Chemical Formula 1 were dissolved in Propylene glycol methylether acetate (PGMEA) at the weight ratios shown in Table 1 below, and filtered through a 0.1 μm PTFE (polytetrafluoroethylene) syringe filter to produce a composition for semiconductor photoresist.

[0098] [Table 1]

[0099] Evaluation 1: Sensitivity and Line Edge Roughness (LER) Evaluation On a 200 mm circular silicon wafer whose surface was vapor-deposited with HMDS, the photoresist compositions according to the above Examples and Comparative Examples were spin-coated at 1500 rpm for 30 seconds each, baked at 110 °C for 60 seconds (post-apply bake, PAB), and then left at room temperature (23 ± 2 °C) for 30 seconds.

[0100] Thereafter, 50 circular pad linear arrays with a diameter of 500 μm were projected onto the 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 EUV increased dose was applied to each pad.

[0101] Thereafter, the resist and the substrate were exposed on a hot plate at 160 °C for 120 seconds and then baked. The baked film was developed in a PGMEA solvent to form a negative tone image. Finally, hot plate baking was performed at 150 °C for 2 minutes to complete the process.

[0102] The residual resist thickness of the exposed pads was measured using ellipsometry. The remaining thickness was measured for each exposure dose, graphed as a function of the exposure dose to measure the sensitivity, the LER was measured from the FE-SEM image, and then the sensitivity and line edge roughness were evaluated according to the following criteria, and the results are shown in Table 2.

[0103] [Sensitivity Evaluation Criteria] -A: Less than 16 mJ / cm 2 Less than -B: 16 mJ / cm or more 2 or more

[0104] [LER Evaluation Criteria] -○: 2 nm or less, -△: More than 2 nm and 5 nm or less, -X: More than 5 nm

[0105] Evaluation 2: Resolution (CD) Evaluation For the pattern wafer on which the process was completed, a Line / Space CD pattern was formed, and then it was transferred to CD-SEM measurement equipment (GC-9380, Hitachi), and the CD (Critical Dimension) size of the part where the half pitch of the mask pattern was 14 nm was measured, and the minimum value among the Space CDs, which is the interval between lines, is shown in Table 2.

[0106]

Table 2

[0107] From the results in Table 2, it can be confirmed that the patterns formed using the semiconductor photoresist compositions according to Examples 1 to 12 exhibit excellent sensitivity, LER, and resolution characteristics compared to Comparative Examples 1 to 9.

[0108] The specific embodiments of the present invention have been described and illustrated above. However, the present invention is not limited to the described embodiments, and it is obvious to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention. Therefore, such modified examples or variations should not be individually understood from the technical idea or perspective of the present invention, and the modified embodiments should be deemed to belong to the scope of the claims of the present invention.

Explanation of Reference Numerals

[0109] 100... Substrate, 102... Thin film, 104... Underlying resist film, 106... Photoresist film, 106a... Exposed region, 106b... Unexposed region, 108... Photoresist pattern, 112... Organic film pattern, 110... Patterned mask, 114... Thin film pattern.

Claims

1. An organometallic compound containing Sn; A carboxylic acid compound represented by the following Chemical Formula 1; and A composition for a semiconductor photoresist, comprising a solvent: 【Chemical 1】 In the Chemical Formula 1, A is a substituted or unsubstituted C5-C50 polycyclic aliphatic hydrocarbon group in which at least two rings are fused, n is an integer of 1 or more.

2. The composition for a semiconductor photoresist according to Claim 1, wherein A is a substituted or unsubstituted adamantyl group, a substituted or unsubstituted norbornyl group, a substituted or unsubstituted isobornyl group, a substituted or unsubstituted tricyclodecanyl group, a substituted or unsubstituted tetracyclododecanyl group, or a combination thereof.

3. The composition for a semiconductor photoresist according to Claim 1, wherein the carboxylic acid compound represented by the Chemical Formula 1 is one selected from the compounds arranged in the following Group 1: 【Chemical 2】

4. The composition for a semiconductor photoresist according to Claim 1, wherein the carboxylic acid compound represented by the Chemical Formula 1 is contained in an amount of 0.01 to 10% by weight based on 100% by weight of the composition for a semiconductor photoresist.

5. The composition for a semiconductor photoresist according to Claim 1, wherein the carboxylic acid compound represented by the Chemical Formula 1 is contained in an amount of 0.05 to 3% by weight based on 100% by weight of the composition for a semiconductor photoresist.

6. The composition for a semiconductor photoresist according to Claim 1, wherein the organometallic compound containing Sn is contained in an amount of 0.5% by weight to 30% by weight based on 100% by weight of the composition for a semiconductor photoresist.

7. The composition for a semiconductor photoresist according to Claim 1, wherein the organometallic compound containing Sn and the carboxylic acid compound represented by the Chemical Formula 1 are contained in a weight ratio of 99:1 to 80:

20.

8. The composition for a semiconductor photoresist according to Claim 1, further comprising an additive such as a surfactant, a crosslinking agent, a leveling agent, an organic acid, a quencher, or a combination thereof.

9. The composition for a semiconductor photoresist according to Claim 1, wherein the organometallic compound containing Sn contains at least one of an organic oxy group and an organic carbonyloxy group.

10. The composition for a semiconductor photoresist according to Claim 1, wherein the organometallic compound containing Sn is represented by the following Chemical Formula 2: [Chemical Formula 3] In the Chemical Formula 2, R ２ is selected from a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, and a substituted or unsubstituted C6-C30 arylalkyl group, R ３ ~R ５ are each independently a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C6-C30 arylalkyl group, alkoxo and aryloxo (-OR ｂ , where R ｂ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), a carboxyl group (-O(CO)R ｃ , R ｃ is hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an alkylamide or dialkylamide (-NR ｄ R ｅ , where R ｄ and R ｅ are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an amidato (-NR ｆ (COR ｇ ), where R ｆ and R ｇ are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an amidinato (-NR ｈ C(NR ｉ )R ｊ , where R ｈ , R ｉ and R ｊ are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), alkylthio and arylthio (-SR ｋ , where R ｋ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof) or a thiocarboxyl group (-S(CO)R ｌ , R ｌ is hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), and R ３ to R ５ at least one of which is alkoxo and aryloxo (-OR ｂ , where R ｂ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), a carboxyl group (-O(C=O)R ｃ , R ｃ is hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an alkylamide or dialkylamide (-NR ｄ R ｅ , where R ｄ and R ｅ are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an amidato (-NR ｆ (COR ｇ ), where R ｆ and R ｇ are each independently hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), an amidinato (-NR ｈ C(NR ｉ )R ｊ , where R ｈ , R ｉ and R ｊ is, independently of each other, hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), alkylthio and arylthio (—SR ｋ , where R ｋ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof) and a thiocarboxyl group (—S(CO)R ｌ , R ｌ is selected from hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof).

11. Said R ３ ~R ５ At least one of which is alkoxo and aryloxo (-OR ｂ , where R ｂ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), and a carboxyl group (-O(C=O)R ｃ , R ｃ is hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof), and is selected from the group consisting of the semiconductor photoresist composition according to claim 10.

12. Said R ２ is a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 aliphatic unsaturated organic group containing one or more double bonds or triple bonds, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C4-C20 heteroaryl group, a carbonyl group, an ethoxy group, a propoxy group, or a combination thereof, R ｂ is a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 alkenyl group, a substituted or unsubstituted C2-C8 alkynyl group, a substituted or unsubstituted C6-C20 aryl group, or a combination thereof, R ｃ is a hydrogen, a substituted or unsubstituted C1-C8 alkyl group, a substituted or unsubstituted C3-C8 cycloalkyl group, a substituted or unsubstituted C2-C8 alkenyl group, a substituted or unsubstituted C2-C8 alkynyl group, a substituted or unsubstituted C6-C20 aryl group, or a combination thereof, the composition for a semiconductor photoresist according to claim 10.

13. The Sn-containing organometallic compound is represented by the following Chemical Formula 3 or Chemical Formula 4, and the semiconductor photoresist composition according to claim 1: 【Chemical Formula 4】 In the Chemical Formula 3, R ６ is a C1-C31 hydrocarbyl group, where 0 < z ≦ 2 and 0 < (z + x) ≦ 4; 【Chemical Formula 5】 In the Chemical Formula 4, R ７ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 aliphatic unsaturated organic group containing one or more double bonds or triple bonds, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C4-C30 heteroaryl group, a carbonyl group, an ethylene oxide group, a propylene oxide group, or a combination thereof, X is sulfur (S), selenium (Se), or tellurium (Te), Y is -OR ｍ or -OC(=O)R ｎ and Said R ｍ is a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof, R ｎ is hydrogen, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C3-C20 cycloalkyl group, a substituted or unsubstituted C2-C20 alkenyl group, a substituted or unsubstituted C2-C20 alkynyl group, a substituted or unsubstituted C6-C30 aryl group, or a combination thereof, The n1, m1, l1, and k1 are each independently an integer from 1 to 20.

14. A step of forming a film to be etched on a substrate; A step of applying the semiconductor photoresist composition according to any one of claims 1 to 13 on the film to be etched to form a photoresist film; A step of patterning the photoresist film to form a photoresist pattern; and A pattern formation method including a step of etching the film to be etched using the photoresist pattern as an etching mask.

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