TWI636974B - Onium salt compound, acid amplifier derived therefrom, resist composition comprising same and method for forming resist pattern - Google Patents

Abstract

Provided are a novel onium salt compound useful as a monomer for forming an acid enhancer, an acid enhancer containing a repeating unit derived therefrom, and a resist composition containing the same. The onium salt compound has a structure of the following Chemical Formula 1, and an acid enhancer containing a repeating unit derived therefrom, when used as an additive when preparing a resist, exhibits high acid yield at the same sensitivity, As a result, the sensitivity of the resist is improved, and a fine resist pattern having excellent sensitivity and resolution is formed.

In the formula, each substituent is the same as defined in the specification.

Description

Onium salt compound, acid enhancer derived therefrom, resist composition containing it, and method for forming resist pattern

The present invention relates to a novel onium salt compound useful as a monomer for forming an acid enhancer, an acid enhancer containing a repeating unit derived therefrom, and a resist composition containing the same.

Recently, lithography technology is actively carrying out high-volume manufacturing (HVM, high volume manufacturing) using ArF immersion light lithography technology (immersion), and the main technology development is to achieve line widths below 50nm. In addition, as the most likely candidate technology in the next generation technology, it is expected to use a photolithography technology of extreme ultraviolet (EUV, extreme UV).

EUV light lithography is a next-generation technology that is being researched mainly to realize patterns below 30 nm. At present, it is expected to be commercialized in all aspects except for defects that occur in energy output or masks. In addition, in the International Semiconductor Technology Blueprint (ITRS roadmap), mass production using this technology is expected to be achieved around 2015. However, when looking at the resist aspect of EUV photolithography, there are still many problems to be solved in order to apply successful technologies such as KrF or ArF.

Among them, it is important to ensure a sufficient amount of photons in order to realize the pattern. Unlike the KrF or ArF photolithography technology, EUV light absorbs all substances, so the path of light is performed in a vacuum state. The mask also uses a non-permeable multilayer film and irradiates the resist by reflection. Therefore, a high power source is required in this process, and a resist having high sensitivity as much as possible is required. Therefore, when the sensitivity (10mJ / cm ² to 15mJ / cm ² ) required for the high energy (92.5eV) of a high EUV is satisfied, there is a problem that a pattern needs to be realized with fewer photons.

In order to solve the problem of achieving a pattern with less acid yield due to fewer photons, and at the same time to obtain a higher acid yield at the same sensitivity, various methods are being researched and developed, as one of which has been As an additive having this characteristic, a technology using an acid amplifier was developed.

Patent Document 1: Korean Patent Publication No. 2011-0095168 (published 2011.8.24)

Patent Document 2: Korean Patent Publication No. 2011-0090825 (published 2011.8.10)

Patent Document 3: Korean Patent Grant No. 1054485 (published on July 27, 2011)

An object of the present invention is to provide a novel onium salt compound for forming an acid enhancer for a resist. When a fine pattern is formed by a lithography method, a high acid yield is also exhibited at the same sensitivity. This can increase the sensitivity of the resist.

Another object of the present invention is to provide a polymer for an acid enhancer of a resist, the polymer for an acid enhancer of the resist containing a repeating unit derived from the onium salt compound.

Still another object of the present invention is to provide a resist composition containing the acid enhancer and a method for forming a resist pattern using the resist composition.

To achieve the object, according to an embodiment of the present invention, an onium salt compound having a structure represented by the following Chemical Formula 1 is provided.

In the chemical formula 1, R ₁ is selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group in which at least one hydrogen is replaced by a halogen atom, and these In the group consisting of combinations, R ₂ and R ₃ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a perfluoroalkyl group, In the group consisting of perfluoroalkoxy, halo, hydroxy, carboxy, cyano, nitro, amine, thio, and combinations thereof, A + is an organic cation having a structure represented by the following Chemical Formula 2,

In the chemical formula 2, R _a and R _b are each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, and an aryl group having 6 to 30 carbon atoms. carbon atoms, 3 to 30 heteroaryl group, a heterocyclic group having a carbon number of 2 to 30 group, and combinations thereof consisting of, or R _a and R _b, in combination with R _a and R _b are S is bonded to form a heterocycloalkyl group having 2 to 7 carbon atoms, and R _c is selected from the group consisting of an arylene group having 6 to 30 carbon atoms, an arylene group having 5 to 30 carbon atoms, and a carbon atom In the group consisting of 2 to 30 heterocycloalkyl groups, R _d is selected from alkyl groups having 1 to 30 carbon atoms substituted or unsubstituted with at least one hydrogen with an electron withdrawing group , A cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, and a combination thereof.

Withdrawing said electron donor is selected from the group consisting of F, Cl, Br, I, CN, NO 2, a halogen group at least one hydrogen substituted with _{haloalkyl, PO (OR e) 2,} OR e, R e COO, SO, SO 2 and SO ₂ R _e group consisting of, at this time, R _e may be selected from the group consisting of alkyl having a carbon number of 1 to 8, at least one hydrogen is substituted with a halogen group and haloalkyl group having a carbon number of 6 to 30 In the group of aryl.

Preferably, R ₂ and R ₃ are each independently an alkyl group having 1 to 6 carbon atoms.

Preferably, R _a and R _b are each independently selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, A heteroaryl group having 3 to 18 carbon atoms and a heterocycloalkyl group having 2 to 18 carbon atoms containing at least one hetero atom selected from the group consisting of N, O, P, and S In the group, or R _a and R _b and S bonded to _Ra and R _{b are} bonded to form a heterocycloalkyl group having 2 to 5 carbon atoms, and R _c is selected from the group consisting of 6 to 18 carbon atoms. An aryl group, a heteroaryl group having 5 to 18 carbon atoms and at least one carbon atom having 2 to 18 carbon atoms having at least one hetero atom selected from the group consisting of N, O, P, and S in the ring In the group consisting of heterocycloalkyl groups, R _d may be an alkyl group having 1 to 6 carbon atoms and 3 to 18 carbon atoms having at least one hydrogen substituted or unsubstituted by an electron withdrawing member. Alkyl groups, aryl groups having 6 to 30 carbon atoms, and aralkyl groups having 7 to 18 carbon atoms.

Preferably, A + may be selected from the group consisting of the following Chemical Formulas 2-1 to 2-12.

According to another embodiment of the present invention, there is provided an acid enhancer as a polymer containing a repeating unit having a structure represented by the following Chemical Formula 9.

Chemical formula 9

In the chemical formula 9, R ₁ is selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group in which at least one hydrogen is replaced by a halogen atom, and these In the group consisting of combinations, R ₂ and R ₃ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a perfluoroalkyl group, In the group consisting of perfluoroalkoxy, halo, hydroxy, carboxy, cyano, nitro, amine, thio, and combinations thereof, A + is an organic cation having a structure represented by the following Chemical Formula 2,

In the chemical formula 2, R _a and R _b are each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, and an aryl group having 6 to 30 carbon atoms. , A heteroaryl group having 3 to 30 carbon atoms, a heterocycloalkyl group having 2 to 30 carbon atoms, and a combination thereof, or R _a and R _b , and R _{b in} combination with R _a S is bonded to form a heterocycloalkyl group having 2 to 7 carbon atoms, and R _c is selected from the group consisting of an arylene group having 6 to 30 carbon atoms, an arylene group having 5 to 30 carbon atoms, and a carbon atom In the group consisting of 2 to 30 heterocycloalkyl groups, R _d is selected from the group consisting of an alkyl group having 1 to 30 carbon atoms substituted or unsubstituted with at least one hydrogen by an electron withdrawing group, and having a carbon number of A group consisting of a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, and combinations thereof.

The acid enhancer may further include a repeating unit derived from an olefin-based compound or a heterocycloalkyl-based compound.

The acid enhancer may further include a repeating unit represented by the following Chemical Formula 10.

In the chemical formula 10, R ₄ is selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group in which at least one hydrogen is replaced by a halogen atom, and these In the group consisting of combinations, R ₅ is selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a heteroalkyl group having 1 to 20 carbon atoms, and a cycloalkane having 3 to 30 carbon atoms. Group, a heterocycloalkyl group having 2 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 3 to 30 carbon atoms, and combinations thereof.

The acid enhancer may be a polymer having a structure represented by the following Chemical Formula 11.

In the chemical formula 11, R ₁ is a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group in which at least one hydrogen is replaced with a halogen atom, and combinations thereof In the group formed, R ₂ and R ₃ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a perfluoroalkyl group, and a perfluoro group. In the group consisting of an alkoxy group, a halogen group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an amine group, a thio group, and a combination thereof, A + is an organic cation having a structure represented by the following Chemical Formula 2,

In the chemical formula 2, R _a and R _b are each independently selected from an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, and an aryl group having 6 to 30 carbon atoms. carbon atoms, 3 to 30 heteroaryl group, a heterocyclic group having a carbon number of 2 to 30 group, and combinations thereof consisting of, or R _a and R _b, in combination with R _a and R _b are S is connected to form a heterocycloalkyl group having 2 to 7 carbon atoms, and R _c is selected from the group consisting of an arylene group having 6 to 30 carbon atoms, an arylene group having 5 to 30 carbon atoms, and carbon In the group consisting of a heterocycloalkyl group having 2 to 30 atoms, R _d is selected from alkyl groups having 1 to 30 carbon atoms and carbon atoms having at least one hydrogen substituted or unsubstituted by an electron withdrawing member. In the group consisting of a cycloalkyl group of 3 to 30, an aryl group of 6 to 30 carbon atoms, and a combination thereof, R _4a to R _4c are each independently selected from the group consisting of a hydrogen atom and a carbon number of 1 to 8 In the group consisting of an alkyl group, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group having at least one hydrogen substituted with a halogen atom, and a combination thereof, R _5a to R _5c are independently selected from the group consisting of a hydrogen atom, The number of carbon atoms is Alkyl group of 1 to 20, heteroalkyl group of 1 to 20 carbon atoms, cycloalkyl group of 3 to 30 carbon atoms, heterocycloalkyl group of 2 to 30 carbon atoms, 6 to 6 carbon atoms In the group consisting of an aryl group of 30, a heteroaryl group having 3 to 30 carbon atoms, and a combination thereof, W is a repeating unit derived from an olefinic compound or a heterocycloalkyl compound, and l, m , N, o, and p respectively represent the number of repeating units in the main chain, l + m + n + o + p = 1, 0 l / (l + m + n + o + p) <0.30, 0 m / (l + m + n + o + p) <0.99, 0 n / (l + m + n + o + p) <0.99, 0 o / (l + m + n + o + p) <0.99 and 0 <p / (l + m + n + o + p) 0.3.

Preferably, R _5a is selected from , and In this group, the acid-sensitive groups are independently selected. In this case, R ', R "and R"' are independently selected from the group consisting of an alkyl group having 1 to 20 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms. (Alkyl group having 1 to 10 carbon atoms) cycloalkyl group, hydroxyalkyl group, alkoxy group having 1 to 20 carbon atoms, (alkoxy group having 1 to 10 carbon atoms) alkyl group, and ethyl group Fluorenyl, ethynylalkyl, carboxyl, (alkyl having 1 to 10 carbon atoms) carboxyl, (cycloalkyl having 3 to 18 carbon atoms) carboxyl, and heterocyclic ring having 3 to 30 carbon atoms In a group of alkyl groups, or adjacent groups can form a saturated or unsaturated hydrocarbon ring or heterocyclic ring having 3 to 30 carbon atoms, and R "" is an alkyl group having 1 to 10 carbon atoms , P is an integer from 0 to 3, q is an integer from 0 to 10, and R _5b is or At this time, R ′ and R ″ are each independently an alkyl group having 1 to 10 carbon atoms, or connected to each other to form a saturated hydrocarbon ring, and r and s are each independently an integer of 0 to 5, and W may be expressed by A repeating unit derived from a compound selected from the group consisting of an alkylene compound, a cyclic olefin compound, a styrene compound, and a furandione compound.

Preferably, W may be a repeating unit derived from a compound selected from the group consisting of a vinyl compound, a styrene compound, a norbornene compound, an indene compound, a quaternary ammonium compound, and a furandione compound. .

More preferably, the acid enhancer may be selected from the group consisting of a compound having a structure of Chemical Formula 11-1 to Chemical Formula 11-21.

In the chemical formulas 11-1 to 11-21, R ₁ is selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and at least one hydrogen is halogenated In the group consisting of atom-substituted haloalkyl groups and combinations thereof, R _4a to R _4c are each independently selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, and an alkoxy group having 1 to 8 carbon atoms Group, a haloalkyl group in which at least one hydrogen is replaced by a halogen atom, and combinations thereof, and l, m, n, o, and p each represent the number of repeating units in the main chain, l + m + n + o + p = 1, 0 l / (l + m + n + o + p) <0.30, 0 m / (l + m + n + o + p) <0.99, 0 n / (l + m + n + o + p) <0.99, 0 o / (l + m + n + o + p) <0.99 and 0 <p / (l + m + n + o + p) 0.3.

Preferably, the acid enhancer has a weight average molecular weight (hereinafter referred to as "Mw") of polystyrene conversion according to gel permeation chromatography (GPC) of 1000 g / mol to 100,000 g / mol.

The molecular weight distribution of the weight average molecular weight to number average molecular weight (Mw / Mn) of the acid enhancer is preferably 1 to 3.

According to still another embodiment of the present invention, a resist composition containing the acid enhancer is provided.

The acid enhancer is preferably contained in an amount of 0.05 to 5% by weight based on the total weight of the resist composition.

According to yet another embodiment of the present invention, a method for forming a resist pattern is provided, which includes the steps of: coating the resist composition on a substrate to form a resist film; and heating the resist. After the film is etched, a step of exposing in a predetermined pattern; and a step of developing the exposed resist pattern.

The exposing step may be performed by using a light source selected from the group consisting of KrF excimer laser, ArF excimer laser, extreme ultraviolet laser, X-ray and electron beam.

Other specific matters of the embodiments of the present invention are included in the following detailed description.

An acid enhancer containing a repeating unit derived from the novel onium salt compound according to the present invention, when used as an additive when preparing a resist, exhibits a high acid yield at the same sensitivity, thereby improving the resist's Sensitivity, forming a fine resist pattern with excellent sensitivity and resolution.

Hereinafter, examples of the present invention will be described in detail. However, this is only provided as an example, and the present invention is not limited thereto. The protection scope of the present invention shall be subject to the description of the scope of patent application.

Unless otherwise stated in this specification, "halo" or "halogen" is any one selected from the group consisting of fluorine, chlorine, bromine, and iodine.

Unless otherwise stated in this specification, the first word "hetero" means a carbon atom substituted with 1 to 3 heteroatoms selected from the group consisting of N, O, S, and P. For example, a heteroalkyl group is one to three carbon atoms of a carbon atom in which an alkyl group is substituted with a heteroatom.

Unless stated otherwise in this specification, "alkyl" means a straight or branched alkyl group having 1 to 30 carbon atoms, and the alkyl group includes a primary alkyl group, a secondary alkyl group, and a tertiary alkyl group. Specific examples of the alkyl group include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and tert-butyl.

Unless otherwise specified in this specification, "alkenyl" means a hydrocarbon group having one, two, three, or cyclic carbon atoms of one or more unsaturated regions, that is, a carbon-carbon sp ² double bond. For example, an alkenyl group may have 2 to 20 carbon atoms (ie, C ₂ -C ₂₀ alkenyl), 2 to 12 carbon atoms (ie, C ₂ -C ₁₂ alkenyl), or 2 to 6 carbon atoms (ie , C ₂ -C ₆ alkenyl). Examples of suitable alkenyl groups include ethylidene or vinyl (-CH = CH ₂ ), allyl (-CH ₂ CH = CH ₂ ), cyclopentenyl (-C ₅ H ₇ ), and 5-hexyl Alkenyl (-CH ₂ CH ₂ CH ₂ CH ₂ CH = CH ₂ ), but is not limited thereto.

Unless otherwise specified in this specification, "alkanediyl" is a divalent atomic group that subtracts two hydrogen atoms from an alkane, and can be represented by the general formula -C _n H _2n- "(alkenediyl)" is a divalent atomic group obtained by subtracting two hydrogen atoms from an alkene, and can be represented by the general formula -C _n H _n- .

Unless otherwise stated in this specification, "cycloalkyl" means a cycloalkyl group having 3 to 30 carbon atoms, and includes monocyclic, bicyclic, tricyclic, and tetracyclic. In addition, it includes adamantyl, norbornyl, and polycyclic cycloalkyl containing norbornyl.

Unless otherwise stated in this specification, "aryl" means a compound containing a benzene ring and a derivative thereof, and may be, for example, toluene or xylene having an alkyl side chain attached to the benzene ring, or two or more Benzene ring, biphenyl, etc. bonded by a single bond, fluorene, xanthine or anthraquinone, etc., where two or more benzene rings are bonded with cycloalkyl or heterocycloalkyl as a medium, naphthalene or anthracene, with two or more benzene rings condensed Wait. Unless otherwise stated in this specification, the aryl group is an aryl group having 6 to 30 carbon atoms.

Unless otherwise specified in this specification, "heterocyclyl" means the number of ring atoms in which more than one (e.g. 1, 2, 3, or 4) carbon atoms are replaced with heteroatoms (e.g., N, O, P, or S) It is a cyclic radical of 4 to 20. In addition, the "heterocyclic group" contains a saturated ring, a partially unsaturated ring, and an aromatic ring (that is, a heteroaromatic ring). In addition, the heterocyclic group includes, for example, an N-oxide or A cyclic aromatic radical of a quaternary ammonium salt. The substituted heterocyclic group includes, for example, a heterocyclic ring substituted with any of the substituents disclosed in this application including a carbonyl group.

Unless otherwise stated in the present specification, a "hydrocarbyl group" is a monovalent hydrocarbon group having 3 to 20 carbon atoms consisting of only carbon and hydrogen, and includes an aliphatic or branched hydrocarbon group and a cyclic hydrocarbon group. Specific examples include hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, cyclohexyl, phenyl, tolyl, xylyl, 2,4,6-trimethylbenzene Groups, benzyl, benzyl, trityl, styryl, non-phenyl, and naphthyl.

Unless otherwise specified in this specification, an "olefin group" is an unsaturated hydrocarbon compound containing a double bond. Examples include, but are not limited to, olefinic hydrocarbon groups, acrylates, styrene, norbornene, indene, fluorene, and furandione.

Unless otherwise stated in this specification, all compounds or substituents may be substituted or unsubstituted. Here, being substituted means that hydrogen is selected from a halogen atom, a hydroxyl group, Carboxyl, cyano, nitro, amine, mercapto, methylmercapto, alkoxy, nitrile, aldehyde, epoxy, ether, ester, carbonyl, ethyl, keto, alkyl, all The fluoroalkyl group, the cycloalkyl group, the heterocycloalkyl group, the allyl group, the benzyl group, the aryl group, the heteroaryl group, a derivative thereof, and a combination thereof are substituted in any one group.

In addition, unless otherwise stated in this specification, "a combination thereof" means that two or more substituents are bonded by a single bond or a linking group, or two or more substituents are bonded by condensation.

The present invention provides a novel onium salt compound of an acid enhancer-forming monomer useful for acid enhancement in a photolithographic resist composition, an acid enhancer as a polymer containing a repeating unit derived therefrom, and A resist composition containing it.

That is, the onium salt compound according to an embodiment of the present invention has a structure represented by the following Chemical Formula 1.

In the chemical formula 1, R ₁ is selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group in which at least one hydrogen is replaced by a halogen atom, and these In the group consisting of combinations, R ₂ and R ₃ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a perfluoroalkyl group, In the group consisting of perfluoroalkoxy, halo, hydroxy, carboxy, cyano, nitro, amine, thio, and combinations thereof, A + is an organic cation having a structure represented by the following Chemical Formula 2,

In the chemical formula 2, R _a and R _b may be each independently selected from the group consisting of an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms, and an aromatic group having 6 to 30 carbon atoms. Group, a heteroaryl group having 3 to 30 carbon atoms, a heterocycloalkyl group having 2 to 30 carbon atoms, and a combination thereof, or R _a and R _b , and R _a and R _b The bonded S is linked to form a heterocycloalkyl group having 2 to 7 carbon atoms, and R _c is selected from the group consisting of an arylene group having 6 to 30 carbon atoms, an arylene group having 5 to 30 carbon atoms, and carbon In the group consisting of heterocycloalkyl groups having 2 to 30 atoms, R _d is selected from alkane groups having 1 to 30 carbon atoms which are substituted or unsubstituted by at least one hydrogen with an electron withdrawing group. Group, cycloalkyl group having 3 to 30 carbon atoms, aryl group having 6 to 30 carbon atoms, and combinations thereof.

Preferably, in the chemical formula 1, R ₁ may be a fluoroalkyl group selected from a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and at least one hydrogen substituted by fluorine. In the group consisting of these and combinations thereof, R ₁ is more preferably selected from the group consisting of a hydrogen atom, a methyl group, an ethyl group, a methoxy group, an ethoxy group, and a trifluoromethyl group.

In addition, in the chemical formula 1, preferably, R ₂ and R ₃ may be independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and a perfluoroalkane. Among the group consisting of a methyl group, a perfluoroalkoxy group, a halogen group, a hydroxyl group, a carboxyl group, a cyano group, a nitro group, an amine group, a thio group, and a combination thereof, a carbon atom such as a methyl group, an ethyl group, or a propyl group is more preferable The number is 1 to 6 alkyl groups.

In addition, in the chemical formula 2, it is preferable that R _a and R _b may be each independently selected from the group consisting of an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 18 carbon atoms, and 6 to 6 carbon atoms. An aryl group of 18, a heteroaryl group having 3 to 18 carbon atoms and at least one hetero atom selected from the group consisting of N, O, P, and S in the ring and a carbon number of 2 to 18 In the group consisting of heterocycloalkyl, or R _a and R _b and S bonded to _Ra and R _{b are} bonded to form a heterocycloalkyl group having 2 to 5 carbon atoms, R _a and R are more preferred _{b is} independently selected from the group consisting of methyl, ethyl, propyl, isopropyl, third butyl, cyclohexyl and phenyl, or R _a and R _{b are} combined with R _a and R _b S is bonded to each other to form a heterocycloalkyl group having 4 to 5 carbon atoms.

Further, in the chemical formula 2, it is preferable that R _c may be selected from the group consisting of an arylene group having 6 to 18 carbon atoms, containing at least one or more in a ring, and being selected from the group consisting of N, O, P, and S. Among the group consisting of a heteroaryl group having 5 to 18 carbon atoms and a heterocycloalkyl group having 2 to 18 carbon atoms, more preferred is a phenylene group or a naphthyldiyl group.

In addition, in the chemical formula 2, preferably, R _d may be an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 18 carbon atoms, or at least one hydrogen substituted with an electron withdrawing member, Aryl groups having 6 to 30 carbon atoms and aralkyl groups having 7 to 18 carbon atoms.

Haloalkyl electron withdrawing body may be Cl, Br, I, CN, NO 2, hydrogen is at least one selected from the group consisting of halo substituted with F, _{a, PO (OR e) 2,} OR e, R e COO, SO, SO group ₂ SO ₂ R _e and consisting in this case, R _e may be selected from the group consisting of alkyl having a carbon number of 1 to 8, at least one hydrogen is substituted with a halogen group and haloalkyl group having a carbon number of 6 to 30's group. Preferably, the electron withdrawing body may be CN or trifluoromethyl.

Therefore, in the chemical formula 1, A + may be selected from the group consisting of the following chemical formulas 2-1 to 2-12.

The onium salt compound of Chemical Formula 1 having the structure described above can be prepared by reacting a compound of Chemical Formula 3 below with a metal salt of a compound of Chemical Formula 4 below.

In the Chemical Formula 3 and Chemical Formula 4, R ₁ to R _3, R _a to R _d and n are as defined the same, M being selected from the group consisting of lithium (Li), sodium (Na) and potassium (K) consisting of Group of metals.

Specifically, the compound of Chemical Formula 3 and the compound of Chemical Formula 4 can be made into a double group of an organic solvent such as dichloromethane, chloroform, dichloroethane, acetonitrile, toluene, benzene, 1,4-dioxane, and water. The reaction is performed in a partial solvent to prepare a compound of Chemical Formula 1. In this case, a polymerization inhibitor may be added.

The compounds of Chemical Formula 3 and Chemical Formula 4 used in the reaction may be prepared by a common preparation method, or a commercially available one may be used if possible.

Specifically, the compound of Chemical Formula 3 can be prepared by the following preparation method, which includes the following steps: when a hydroxyl-containing ring compound of the following Chemical Formula 5 and a sulfonium halide of the following Chemical Formula 6 are present in a basic compound Under reaction A step of preparing a compound of the following Chemical Formula 7; and a step of reacting the compound of the Chemical Formula 7 with a fluorene compound and a trifluoromethanesulfonic anhydride of the following Chemical Formula 8.

In the Chemical Formula 5 to Chemical Formula 8, R _a, R _b and R _d are the same as defined above, X is selected from the group consisting of carbon atoms is 6, the number of carbon atoms to 30 aryl heteroaryl 5 to 30 In the group consisting of a radical and a heterocycloalkyl group having 2 to 30 carbon atoms, a phenyl group or a naphthyl group is preferable, and Y is a halogen group, and preferably a chloro group.

Specifically, a compound of Chemical Formula 5 such as phenol can be made in Chemical Formula 6 Compounds such as 3,5-bis-trifluoromethylbenzenesulfonyl chloride in a reaction solvent such as dichloromethane, chloroform, dichloroethane, acetonitrile, toluene, benzene, 1,4-dioxane, etc. When a basic compound such as triethylamine is reacted to obtain a compound of Chemical Formula 7, the compound of Chemical Formula 7 and the fluorene compound of Chemical Formula 8 are dissolved in an organic solvent, and then trifluoro is made in an ice bath. Methanesulfonic anhydride is reacted, and potassium carbonate or the like is added after the reaction to neutralize, thereby obtaining a compound of Chemical Formula 3.

According to another embodiment of the present invention, there is provided an acid enhancer as a polymer containing a repeating unit derived from the onium salt compound of Chemical Formula 1 and having a structure of Chemical Formula 9 below.

In the chemical formula 9, A +, R ₁ to R ₃ , and n are the same as defined above.

The acid enhancer may further include a repeating unit derived from an olefin-based compound or a heterocycloalkyl-based compound.

Specifically, a compound selected from the group consisting of an alkylene compound, a cyclic olefin compound, a styrene compound, and a furandione compound can be used. Preferably, a compound selected from the group consisting of a vinyl compound and styrene can be used. Compounds in the group consisting of compound-type compounds, norbornene-type compounds, indene-type compounds, fluorene-type compounds, and furandione-type compounds.

The acid enhancer may further include a repeating unit derived from an acrylic compound and represented by Chemical Formula 10 below.

In the chemical formula 10, R ₄ may be a haloalkyl group selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, at least one hydrogen substituted with a halogen atom, and In the group consisting of these combinations, R ₅ may be selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a heteroalkyl group having 1 to 20 carbon atoms, and 3 to 30 carbon atoms. The group consisting of cycloalkyl, heterocycloalkyl having 2 to 30 carbon atoms, aryl having 6 to 30 carbon atoms, heteroaryl having 3 to 30 carbon atoms, and combinations thereof Any of these may be substituted with a substituent selected from the group consisting of a carbonyl group, a carboxyl group, an ether group, a nitrile group, and a halogen group.

Specifically, the acid enhancer according to the present invention may be a compound having a structure represented by the following Chemical Formula 11.

In the chemical formula 11, A +, R ₁ to R ₃ and n are the same as defined above, and R _4a to R _4c are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, and a carbon number In the group consisting of an alkoxy group of 1 to 8, a halogenated alkyl group having at least one hydrogen substituted with a halogen atom, and a combination thereof, R _5a to R _5c may be independently selected from the group consisting of a hydrogen atom and a carbon number of 1 to 20 alkyl groups, heteroalkyl groups having 1 to 20 carbon atoms, cycloalkyl groups having 3 to 30 carbon atoms, heterocycloalkyl groups having 2 to 30 carbon atoms, and 6 to 30 carbon atoms Any one of a group consisting of an aryl group, a heteroaryl group having 3 to 30 carbon atoms, and a combination thereof, and may be selected from the group consisting of a carbonyl group, a carboxyl group, an ether group, a nitrile group, and a halogen group. Substituents in the group are substituted, W is a repeating unit derived from an olefinic compound or a heterocycloalkyl compound, l, m, n, o, and p represent the number of repeating units in the main chain, respectively. m + n + o + p = 1, 0 l / (l + m + n + o + p) <0.30, 0 m / (l + m + n + o + p) <0.99, 0 n / (l + m + n + o + p) <0.99, 0 o / (l + m + n + o + p) <0.99 and 0 <p / (l + m + n + o + p) 0.3.

Preferably, in the chemical formula 11, R _5a may be an acid labile group. As described above, since the acid-sensitive group is contained, the exposed portion is converted from hydrophobic to hydrophilic due to the deprotection reaction of the acid during exposure. As a result, the exposed portion can be easily washed with the developing solution during development.

Specifically, R _5a is selected from , with The acid-sensitive groups in the group formed, in this case, R ', R "and R"' are independently selected from the group consisting of an alkyl group having 1 to 20 carbon atoms and a cycloalkyl group having 3 to 30 carbon atoms (Alkyl group having 1 to 10 carbon atoms) cycloalkyl group, hydroxyalkyl group, alkoxy group having 1 to 20 carbon atoms, (alkoxy group having 1 to 10 carbon atoms) alkyl group, and ethyl group Fluorenyl, ethynylalkyl, carboxyl, (alkyl having 1 to 10 carbon atoms) carboxyl, (cycloalkyl having 3 to 18 carbon atoms) carboxyl, and heterocyclic ring having 3 to 30 carbon atoms In a group of alkyl groups, or adjacent groups can be connected to form a saturated or unsaturated hydrocarbon ring or heterocyclic ring having 3 to 30 carbon atoms, and R "" is an alkane having 1 to 10 carbon atoms. Base, p is an integer from 0 to 3, and q is an integer from 0 to 10.

More preferably, in the chemical formula 11, R _5a is selected from the group consisting of a third butyl group, a trimethylsilyl group, a hydroxy-2-ethyl group, a 1-methoxypropyl group, and a 1-methoxy-1-methyl group. Ethyl, 1-ethoxypropyl, 1-ethoxy-1-methylethyl, 1-methoxy-1-ethyl, 1-ethoxy-1-ethyl, tert-butyl Oxy-2-ethyl, 1-isobutoxy-1-ethyl, and a group consisting of the following chemical formulas 12a to 12j,

In the chemical formulas 12a to 12j, R ′, R ″, and R ″ ′ are each independently selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, and a carbon number. In the group consisting of an alkylsilyl group having 1 to 10 and a cycloalkylsilyl group having 3 to 18 carbon atoms, a and e are integers of 0 to 15, and b is an integer of 0 to 11, c and d are each independently an integer from 0 to 9, f is an integer from 0 to 7, g and i are each independently an integer from 0 to 6, 0 c + d 17, 0 c + f 15. It may be still more preferably selected from the group consisting of the following chemical formulas 13a to 13h.

R _5b may be a lactone group. Since such a lactone group is contained, the adhesion to the wafer can be enhanced.

Specifically, R _5b is or At this time, R ′ and R ″ are each independently an alkyl group having 1 to 10 carbon atoms, or connected to each other to form a saturated hydrocarbon ring, and r and s may be each independently an integer of 0 to 5, and more preferably may be the following Said Chemical Formula 14a or Chemical Formula 14b.

In addition, in the chemical formula 11, W may be a repeating unit derived from a compound selected from the group consisting of an alkylene compound, a cyclic olefin compound, a styrene compound, and a furandione compound. More preferably, it may be a repeating unit derived from a compound selected from the group consisting of a vinyl compound, a styrene compound, a norbornene compound, an indene compound, a fluorene compound, and a furandione compound. .

In addition, in the chemical formula 11, the repeating units 1, m, n, o, and p represent the content of each repeating unit in the main chain, and meanwhile, the substitution rate at which the copolymer is dissolved in the developing solution. The acid enhancer according to the present invention contains 0 <l / (l + m + n + o + p) 0.30, 0 m / (l + m + n + o + p) <0.99, 0 <n / (l + m + n + o + p) <0.99, 0 <o / (l + m + n + o + p) < 0.99 and 0 <p / (l + m + n + o + p) <0.3. The repeating unit is contained in the proportion, so that it can exhibit a hydrophobic property with low affinity to water during liquid immersion exposure, and more preferably contains repeating unit p derived from the monomer of Chemical Formula 1 at 10 mol% or less, so that It is possible to reduce the CA value at the time of development and achieve the effect of reducing defects.

The anti-corrosive additive according to the present invention having the structure described above may be a block copolymer, a random copolymer, or a graft copolymer.

Specific examples of the acid enhancer according to the present invention include compounds having a structure represented by the following Chemical Formula 11-1 to Chemical Formula 11-21. In the structural formula, the order of each repeating unit can be changed.

In the formulas 11-1 to 11-21 in the formula, R _1, R _4a and R _4c, identical l, m, n, o and p are as defined above.

In the polymer, if described with reference to Chemical Formula 11-1, the copolymer having the structure described above, when irradiated with EUV (or KrF, ArF) light, the onium compound bonded to the main chain of the [p] substituent The cations are cleaved in the form of free radicals, and a strong acid is formed in the anion portion hanging on the chain. By the strong acid thus generated, the benzenesulfonyl group substituted with a trifluoro form in the structure of the chemical formula 11-1 in the cationic moiety is cleaved to generate benzenesulfonic acid, and an acid is generated in addition to the acid generated in the main chain. . As a result, the sensitivity of the resist can be enhanced. The reaction mechanism described above has been described using EUV resist as an example, but it is not limited to this. It can be applied to chemically amplified resists (KrF, ArF, X-ray, etc.) (Chemically Amplified Resist, CAR). ) Types of all photolithography techniques.

The acid-enhancing agent according to the present invention may have a weight-average molecular weight (hereinafter referred to as "Mw") of polystyrene conversion based on gel permeation chromatography (GPC) of 1,000 g / mol to 100,000 g / mol. If the weight average molecular weight of the acid enhancer is too small, it may cause dissolution in pure water during mixing or liquid immersion exposure. If it is too large, it may be difficult to form an appropriate film or reduce alkali solubility. Preferably the weight average molecular weight is 2000g / mol to 10000g / mol, it will not dissolve in pure water Out, and show excellent solubility to the developer.

In addition, the molecular weight distribution of the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) of the acid enhancer is preferably 1 to 3, and more preferably 1 to 2. In addition, if the molecular weight distribution of the polymer exceeds 3, the line edge roughness may be poor. Therefore, when a resist additive belonging to the aforementioned weight average molecular weight and molecular weight distribution range is used as a photolithographic adhesive composition, corresponding physical properties can be exhibited in terms of developability, coatability, and heat resistance.

The acid enhancer according to the present invention having the above-mentioned structure can make an onium salt compound having a structure represented by the following Chemical Formula 1 and an optional olefin monomer, and acrylic acid having a structure represented by the following Chemical Formulas 10a to 10c The monomer-like monomers are prepared by polymerization methods such as bulk polymerization, solution polymerization, suspension polymerization, bulk suspension polymerization, and emulsion polymerization.

In the chemical formulas 10a to 10c, R _4a to R _5c are the same as defined above.

Preferably, the acid enhancer according to the present invention can be polymerized by radical polymerization. In this case, as the radical polymerization initiator, for example, azobisisobutyronitrile (AIBN), benzamidine peroxide (BPO), and peroxidation can be used. There are no particular restrictions on conventional free-radical polymerization initiators such as laurel tincture, azobisisocaprolactam butyronitrile, azobisisovaleronitrile, and third butyl hydrogen peroxide.

In addition, as the polymerization solvent, one or more solvents selected from the group consisting of benzene, toluene, xylene, halogenated benzene, diethyl ether, tetrahydrofuran, esters, ethers, lactones, ketones, amidines, and alcohols are used. .

The polymerization temperature during the polymerization reaction is appropriately selected and used according to the type of the catalyst. In addition, the molecular weight distribution of the prepared polymer can be appropriately adjusted by changing the amount of the polymerization initiator and the reaction time. The unreacted monomers and by-products remaining in the reaction mixture after the completion of the polymerization reaction are preferably removed by a solvent precipitation method.

According to another embodiment of the present invention, a resist composition containing the acid enhancer is provided.

Specifically, the resist composition contains an acid enhancer, an acid generator, and a solvent, and may optionally contain a commonly used base polymer for resist and other additives.

The acid enhancer is the same as described above, and may contain 0.05 to 5% by weight based on the total weight of the resist composition. If the content of the acid enhancer is less than 0.05% by weight, the effect brought about by the use of additives is very small, and if it exceeds 5% by weight, the appropriate CA value is exceeded, and a watermark defect may occur, which is not preferable.

The acid generator is a photoacid generator (hereinafter referred to as "PAG"), and iodonium salts and sulfonium salts of onium salts can be used. (sulfonium salts), phosphonium salts, diazonium salts, pyridinium salts, sulfonium imines, and the like, one or more of the sulfonium salts represented by the following Chemical Formula 15 and Chemical Formula 16 can be preferably used, and more preferably can be used Triphenylphosphonium salt of perfluorobutylsulfonic acid.

In the chemical formula, X ₁ , X ₂ , Y ₁ and Y ₂ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an allyl group, and a perfluoroalkyl group having 1 to 10 carbon atoms. , Benzyl, aryl group having 6 to 30 carbon atoms, and any combination thereof, X ₁ and X ₂ and Y ₁ and Y ₂ may be combined with each other to form a group having 3 to 30 carbon atoms Saturated or unsaturated hydrocarbon ring, X ₃ , X ₄ , X ₅ , Y ₃ , Y ₄ and Y ₅ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a halogen group, and a carbon number of 1 to Alkoxy group 30, aryl group having 6 to 30 carbon atoms, thiophenoxy, thioalkoxy group having 1 to 30 carbon atoms, alkoxy group having 1 to 20 carbon atoms Any of the groups consisting of alkoxycarbonylmethoxy and combinations thereof, Z of the anionic part is OSO ₂ CF ₃ , OSO ₂ C ₄ F ₉ , OSO ₂ C ₈ F ₁₇ , N (CF ₃ ) ₂ , N (C ₂ F ₅ ) ₂ , N (C ₄ F ₉ ) ₂ , C (CF ₃ ) ₃ , C (C ₂ F ₅ ) ₃ , C (C ₄ F ₉ ) ₃ or the following chemical formula The functional group represented by 17.

In the chemical formula 17, V ₁ and V ₂ are each independently a halogen atom, W ₁ is-(C = O)-or-(SO ₂ )-, and W ₂ is an alkylene group having 1 to 10 carbon atoms, W ₃ is selected from the group consisting of a cycloalkyl group having 3 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, an aralkyl group having 7 to 30 carbon atoms, an aryloxy group having 6 to 30 carbon atoms, and a carbon atom Any of the group consisting of an arylthio group having 6 to 30 and a heterocyclic group having 5 to 30 carbon atoms, W ₄ is selected from the group consisting of a hydrogen atom, a halogen group, and an alkyl group having 1 to 10 carbon atoms Group, alkoxy group having 1 to 10 carbon atoms, haloalkyl group having 1 to 10 carbon atoms, alkylthio group having 1 to 10 carbon atoms, aryl group having 6 to 30 carbon atoms, and combinations thereof In any of the groups, o is an integer from 0 to 1, and p is an integer from 0 to 2.

The anion in the acid generator contains a cyclic alkyl group, so that the diffusion length of the acid in the resist film can be appropriately kept short, and high permeability is exhibited. As a result, a high-resolution resist can be obtained.

Preferably, the anion part Z- may be selected from the group consisting of functional groups represented by the following Chemical Formulae 18-1 to 18-36.

In addition, in the chemical formula 15 and the chemical formula 16, it is preferable to include a structure represented by the following chemical formulas 19-1 to 19-16 as a cationic moiety.

The acid generators described above may be used alone or in combination of two or more. In addition, the acid generator is 100 parts by weight relative to the polymer solid content. The content may be 0.3 to 15 parts by weight, preferably 0.5 to 10 parts by weight, and more preferably 2 to 10 parts by weight. When the content of the acid generator exceeds 15 parts by weight, the perpendicularity of the pattern is significantly reduced, and if it is less than 0.3 parts by weight, the flexibility of the pattern may be reduced.

In order to obtain a uniform and smooth resist coating film, the acid enhancer and the acid generator are preferably dissolved and used in a solvent having an appropriate volatilization rate and viscosity. Examples of the solvent that can be used in the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, methyl acetate cellosolve, ethyl acetate cellosolve, and propylene glycol monomethyl Ethers such as methyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methyl isopropyl ketone, cyclohexanone, methyl 2-hydroxypropionate, ethyl Ketones such as ethyl-2-hydroxypropionate, 2-heptanone, ethyl lactate, and γ-butyrolactone, etc., may be used alone or in combination of two or more.

The amount of the solvent can be appropriately adjusted according to the physical properties of the solvent, that is, volatility, viscosity, etc., so that a uniform resist film can be formed.

As the base polymer for resist, any base resin may be used as long as it is a base resin when forming a resist film, and there is no particular limitation. As a specific example, a polymer selected from (meth) acrylate polymer, (α-trifluorometh) acrylate-maleic anhydride copolymer, cycloolefin-maleic anhydride copolymer, polynorbornene, Polymer compounds obtained by ring-opening metathesis reaction of olefins, polymer compounds obtained by adding hydrogen to polymers obtained by ring-opening metathesis reaction of cycloolefins, hydroxystyrene and (meth) acrylate derivatives Polymer compounds copolymerized with any of styrene, vinylnaphthalene, vinylanthracene, vinylfluorene, hydroxyvinylnaphthalene, hydroxyvinylanthracene, indene, hydroxyindene, pinene, norbornadiene, Novolac resins and their mixtures.

The base polymer may be contained in an amount of 3 to 20% by weight based on the total weight of the resist composition. If the content of the polymer is less than 3% by weight, the viscosity of the composition is too low, so that it is difficult to form a thin film of a desired thickness, and a pattern loss is serious due to a relatively large amount of photoacid generator. 20% by weight, the thickness of the film is too thick to reduce the radiation penetration, and it is difficult to obtain a longitudinal pattern.

In addition, the resist composition according to the present invention may further contain additives for the purpose of improving coatability and the like.

The additive is not particularly limited as long as it is an additive generally applicable to a resist composition. Specific examples include an alkaline dissolution inhibitor, an acid diffusion inhibitor, and a surfactant. Among them, It contains one kind alone or two or more kinds.

The alkaline dissolution inhibitor can be used as long as it is an alkaline dissolution inhibitor generally applicable to a resist composition, and specific examples thereof include phenol and a carboxylic acid derivative.

The acid diffusion inhibitor has the effect of suppressing diffusion and development when the acid generated from the acid generator is diffused into the resist film by light irradiation, and suppresses a chemical reaction in the unexposed portion. By using such an acid diffusion inhibitor, it is possible to improve the storage stability of the radiation-sensitive linear resin composition while further improving the resolution as a resist, and to suppress the variation in time (PED) caused by exposure to development processing. The line width of the resist pattern varies.

As such an acid diffusion inhibitor, a basic compound can be used, and specific examples thereof include amine, methylamine, isopropylamine, n-hexylamine, cyclopentylamine, methylenediamine, ethylenediamine, and dimethylamine. , Diisopropylamine, diethylenediamine, N, N-dimethylmethylenediamine, N, N-dimethylethylenediamine, trimethylamine, triethylamine, N, N, N ', N'- Tetramethyl Methyldiamine, N, N, N ', N'-tetramethylethylenediamine, N, N, N', N'-tetramethyltetraethylethylpentamine, diethylamine, methylethyl Propylamine, benzylamine, phenethylamine, benzyldimethylamine, tetramethylammonium hydroxide, aniline, N, N-dimethylaniline triphenylamine, phenylenediamine, pyrrole, oxazole, isoxazole, Thiazole, isothiazole, imidazole, pyrazole, pyrroline, pyrrolidine, imidazoline derivative, imidazolidine derivative, pyridine derivative, pyridazine derivative, pyrimidine derivative, pyrazine derivative, pyrazoline derivative, Pyrazolidine derivatives, piperidine derivatives, piperazine derivatives, morpholine and other amines, amino acids, indole carboxylic acids, amino acid derivatives (such as nicotinic acid, alanine, spermine, aspartic acid Amino acid, etc.), 3-pyridinesulfonic acid, p-toluenesulfonic acid pyridine salt, 2-hydroxypyridine, amino-m-cresol, 2,4-quinolinediol, 2- (2-hydroxyethyl) pyridine, 1 -Nitrogen compounds such as (2-hydroxyethyl) piperazine, formamidine, N-methylformamide, N, N-dimethylformamide, acetamide, N-methylacetamide, N , N-dimethylacetamide, propylamidine, benzamidine derivatives such as amidine, or phthalimidine, Amber (PEI), maleic acyl imine (PEI) derivative.

The content of the acid diffusion inhibitor may be 0.01 to 5 parts by weight, and preferably 0.1 to 1 part by weight, relative to 100 parts by weight of the polymer solid content. If the content of the acid diffusion inhibitor is less than 0.01 part by weight, the influence of the delay time after exposure is large, which may affect the image shape. If it exceeds 5 parts by weight, the resolution and sensitivity may be reduced.

The surfactant is used to improve coatability and developability. Specific examples include polyoxyethylene lauryl ether, octadecyl polyoxyethylene ether, polyoxyethylene, and polyethylene glycol dilaurate. , But not limited to this.

When a resist pattern is formed using the resist composition according to the present invention having the composition as described above, improved line width roughness is exhibited, and both the C / H pattern and the L / S pattern are excellent. Resolution. In addition, it has a good process window, so it is possible to obtain an excellent pattern profile regardless of the type of substrate, and to show improved contrast. Therefore, the resist composition is induced by X-rays such as far ultraviolet rays such as KrF excimer laser, ArF excimer laser or F ₂ excimer laser, synchrotron radiation, and radiation of charged particles such as EUV. The chemically amplified positive photolithographic composition is useful.

According to yet another embodiment of the present invention, a method for forming a pattern using the resist composition is provided.

Specifically, the method of forming the pattern includes the steps of: forming a resist film by coating the resist composition on a substrate; and performing a step of exposing the resist film in a predetermined pattern after the heat treatment of the resist film; and A step of developing the exposed resist pattern.

The substrate may be a wafer substrate, and a method for coating the substrate may be spin coating, flow coating, or roll coating.

Specifically, the thickness of the coating film on a substrate such as a silicon wafer is 0.3 μm to 2.0 μm, and it is pre-baked at 60 ° C. to 150 ° C. for 1 to 10 minutes, preferably at 80 ° C. to 130 ° C. for 1 minute to 5 minute.

Next, in order to form a fine pattern, a part of the resist film is irradiated with radiation. In this case, the usable radiation is not particularly limited, but I-rays that are ultraviolet rays, KrF excimer lasers that are far ultraviolet rays, ArF excimer lasers, F ₂ excimer lasers, X-rays, and charged particles can be used. Electron rays and the like can be appropriately selected and used according to the type of the acid generator.

Specifically, the radiation is irradiated so that the exposure amount is about 1 mJ / cm ² to 200 mJ / cm ² , preferably about 10 mJ / cm ² to 100 mJ / cm ² , and then post-exposure baking (PEB) is performed at 60 ° C. to 150 ° C. for 1 minute. To 5 minutes, preferably 1 minute to 3 minutes after baking at 80 ° C to 130 ° C.

The exposed resist pattern after the exposure step is developed by dipping (dip) method, puddle method, spray method, or the like, and immersed in a developing solution for 0.1 minute to 3 minutes for development, preferably 0.5 minute to 2 minutes, thereby forming a desired pattern on the substrate. In this case, as the usable developer, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium methane silicate, ammonia, ethylamine, n-propylamine, triethylamine, and tetramethyl hydroxide can be used. As an aqueous solution such as ammonium or tetraethylammonium hydroxide, tetramethylammonium hydroxide is preferably used.

In addition, the developing solution may optionally contain additives such as a surfactant or a water-soluble alcohol.

By the method for forming a pattern using the resist composition according to the present invention as described above, a fine resist pattern having excellent sensitivity and resolution can be formed.

Hereinafter, the embodiments of the present invention are described in detail so that those skilled in the art to which the present invention pertains can easily implement. However, the present invention can be implemented in various ways, and is not limited to the embodiments described herein.

Synthesis Example 1

In a round bottom flask, 6.9 g of phenol and 23 g of 3,5-Bis-trifluoromethyl-benzenesulfonyl chloride were mixed with 200 ml of dichloromethane. After being dissolved, 8.9 g of triethylamine was slowly added dropwise to the solution prepared by stirring at room temperature, followed by stirring for 2 hours. After confirming the completion of the reaction by TLC, the resulting reaction solution was washed with an aqueous sodium hydroxide solution, and then washed twice with distilled water, and the organic layer was separated and collected. 3,5-Bis-trifluoromethyl-benzenesulfonic acid phenyl ester (i) was obtained by removing the solvent component in the collected organic layer with a reduced-pressure still. (22.2g, yield 81%). The structure of the obtained compound was confirmed by ¹ H NMR.

¹ H NMR (CDCl ₃ , internal standard: tetramethylsilane): (ppm) 7.00 (d, 2H), 7.3 to 7.4 (t, 3H), 8.2 (s, 1H), 8.3 (s, 1H)

Synthesis Example 2

5 g of phenyl 3,5-bis-trifluoromethyl-benzenesulfonate (i) and 3 g of phenyl sulfoxide synthesized in Synthesis Example 1 were put into a round-bottomed flask and used as a reaction. The solvent was dissolved using 50 ml of dichloromethane. After preparing the bath to cool the reaction flask to -10 ° C, 4.8 g of trifluoromethane sulfonic anhydride was slowly added dropwise into the reactor. After the dropwise addition was completed, the inside temperature of the reactor was kept at -10 ° C while being stirred for 2 hours. After confirming the completion of the reaction by TLC, the reaction solution obtained as a result was added to an aqueous solution of potassium carbonate (K ₂ CO ₃ ) and vigorously stirred to neutralize it. After the neutralization process was completed, it was washed twice with distilled water, and only the organic layer was separated and collected. The solvent in the collected organic layer was removed by distillation under reduced pressure, and the resulting residue was dissolved with a small amount of dichloromethane, and then poured into n-hexane to solidify to obtain the target compound (ii) (5.2 in the following reaction formula 2) g, yield 74%). The structure of the obtained compound was confirmed by ¹ H NMR.

¹ H NMR (CDCl ₃ , internal standard: tetramethylsilane): (ppm) 7.4 to 8.0 (m, 17H)

Synthesis Example 3

14 g of the compound (ii) synthesized in said Synthesis Example 2 and 13 g of the sodium sulfonate (iii) in the following reaction formula 3 were added to a two-component solvent of dichloromethane and distilled water, and a small amount of Irganox® 1010 (manufactured by Ciba-Geigy) as a polymerization inhibitor. When the degree of anion substitution in the reactant was confirmed by ¹⁹ F NMR, and when the substitution was not completed, a sodium sulfonate (iii) was additionally added. After the substitution reaction was completed, the resulting reactant was separated from the aqueous layer and the organic layer, and only the organic layer was collected, and the solvent in the organic layer was removed by distillation under reduced pressure. The obtained residue was dissolved with a small amount of dichloromethane, and then poured into n-hexane to be solidified to obtain the target compound (iv) (11.7 g, yield 79%) in the following reaction formula 3. The structure of the obtained compound was confirmed by ¹ H NMR.

¹ H NMR (CDCl ₃ , internal standard: tetramethylsilane): (ppm) 4.7 (t, 2H), 5.6 (s, 1H), 6.2 (s, 1H), 7.6 to 8.2 (m, 17H)

Synthesis Example 4

In Synthesis Example 1, except that benzenesulfonyl chloride was used in place of 3,5-bis-trifluoromethylbenzenesulfonyl chloride to prepare phenylbenzenesulfonate and used in Synthesis Example 2, it was carried out in order. By the reactions in Synthesis Examples 1 to 3, a compound (v) having the following structure was prepared.

¹ H NMR (CDCl ₃ , internal standard: tetramethylsilane): (ppm) 4.7 (t, 2H), 5.6 (s, 1H), 6.2 (s, 1H), 6.8 (d, 2H), 7.5 (t , 2H), 7.7 ~ 8.0 (m, 15H)

Synthesis Example 5

In the above Synthesis Example 1, a compound (vi) having the following structure was prepared by sequentially performing the reactions in Synthesis Example 1 to Synthesis Example 3 using tetramethylene fluorene instead of phenyl fluorene.

¹ H NMR (CDCl ₃ , internal standard: tetramethylsilane): (ppm) 2.4 (d, 4H), 4.2 (m, 4H), 4.7 (t, 2H), 5.6 (s, 1H), 6.2 (s , 1H), 6.8 (d, 2H), 7.7 ~ 8.0 (m, 5H)

Polymer Synthesis Example 1

4.5 g of norbornene, a polymerization monomer, 4.9 g of dimethyl azobis isobutylate as a polymerization initiator, and 106 g of 1,4-dioxane Pour together into a flask to dissolve. After the inside of the flask was replaced with nitrogen with nitrogen, the temperature inside the reactor was heated to 50 ° C. When the internal temperature of the reactor reached 50 ° C, 14.5 g of 2-isopropyl-2-adamantyl methacrylate and 10.5 g of norbornene were used by a supply pump. Lactone-methacrylate (norbornene carpolactone methacrylate), 11.2 g of 3-hydroxy-1-adamantyl methacrylate, and the compound prepared in Synthesis Example 3 (iv) 12g via 2 small While dripping into 53 g of 1,4-dioxane, the internal temperature of the reactor was heated to 75 ° C. After the completion of the dropwise addition, the polymerization reaction was performed at the same temperature for 3 hours. After the polymerization was completed, the resulting reaction solution was cooled to normal temperature. The reaction solution cooled to normal temperature was subjected to precipitation reaction using an excess of n-hexane, and then filtered. During filtration, the polymer was washed with the same solvent and then dried under reduced pressure. As a result, 35 g of a polymer (vii) having the following structure was obtained. The polystyrene-equivalent weight average molecular weight (Mw) of the polymer was 5692, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight was 1.53.

(In the formula, the molar ratio of l: m: n: o: p is 0.1: 0.2: 0.3: 0.3: 0.1)

Polymer Synthesis Example 2

As a monomer for polymerization, 8.5 g of 3-bicyclo [2.2.1] hept-5-en-2-yl-third butoxycarbonyloxy-propionic acid third butyl ester (3-bicyclo [ 2.2.1] hept-5-en-2-yl-tert-butoxycarbonyloxy-propionic acid tert-butyl ester) Instead of norbornene in Synthesis Example 1 of the polymer, 10.2 g of 1- ( 2-adamantylprop-2-yl) methacrylate) (1- (2-adamantylpropan-2-yl) methacrylate) substituted 2-isopropyl-2-adamantyl Alkyl methacrylate using 6.5 g of γ-butyrolactone methacrylate instead of norbornene caprolactone-methacrylate instead of 3-hydroxy-1-adamantyl methacrylate Furthermore, the same method as in Synthesis Example 1 of the polymer was performed except that 10 g of the compound (iv) prepared in Synthesis Example 3 was used, and 18 g of a polymer (viii) having the following structure was obtained. . The polystyrene-equivalent weight average molecular weight (Mw) of this polymer was 21,116, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight was 2.98.

(In the formula, the molar ratio of l: m: n: p is 0.3: 0.3: 0.3: 0.1)

Polymer Synthesis Example 3

As the monomer for polymerization, except that 4.8 g of norbornene was used instead of 8.5 g of 3-bicyclo [2.2.1] hept-5-en-2-yl-tert-butoxycarbonyloxy-propionate tert-butyl Except for the ester, 16.5 g of a polymer (ix) having the following structure was prepared by the same method as in Synthesis Example 2 of the polymer. The polystyrene-equivalent weight average molecular weight (Mw) of this polymer was 21,116, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight was 2.98.

(In the formula, the molar ratio of l: m: n: p is 0.1: 0.4: 0.4: 0.1)

Polymer Synthesis Example 4

As a monomer for polymerization, in addition to using 9.2 g of the substituted compound (iv) of the compound (v) prepared in Synthesis Example 4, 15 g of 2-isopropyl-2-adamantyl methacrylate was used instead. Except for 1- (2-adamantylprop-2-yl) methacrylate, the same method as in Synthesis Example 3 of the polymer was performed, and 14 g of a polymer (x) having the following structure was obtained. The polystyrene-equivalent weight average molecular weight (Mw) of this polymer was 21,116, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight was 2.98.

(In the formula, the molar ratio of l: m: n: p is 0.1: 0.4: 0.4: 0.1)

Polymer Synthesis Example 5

As a monomer for polymerization, except that 8.3 g of the substituted compound (iv) of the compound (vi) prepared in Synthesis Example 5 was used, the same method as in Synthesis Example 3 of the polymer was carried out to obtain a polymer having the following structure: Polymer (xi) 13.5 g. The polystyrene-equivalent weight average molecular weight (Mw) of this polymer was 21,116, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight was 2.98.

(In the formula, the molar ratio of l: m: n: p is 10: 40: 40: 10)

Experimental example: forming a resist film and measuring the characteristics of the prepared resist film

5 g of the polymer (ix) prepared in Synthesis Example 3 of the polymer, 0.31 g of a photoacid generator represented by the following Chemical Formula 20, and triisopropanol amine as an acid diffusion inhibitor 0.07 g was dissolved in 80 g of propylene glycol monoethyl ether acetate (PGMEA, propyleneglycol monoethyl ether acetate), and then filtered through a 0.2 μm polypropylene filter to obtain a resist.

Chemical formula 20

An anti-reflection film (BARC) having a film thickness of 90 nm was formed on a silicon substrate, and the prepared resist was coated on the substrate on which the anti-reflection film was formed, and then baked at 110 ° C. for 60 seconds to form a film thickness. 20nm photolithographic film.

Next, in order to simulate liquid immersion exposure, the exposed film was washed with pure water for 5 minutes. That is, exposure was performed with an ArF scanner 306C (NA = 0.78, 6% half-tone mask) manufactured by Nikon, followed by washing with pure water for 5 minutes, and post-exposure baking (PEB) at 110 ° C for 60 seconds, followed by 2.38. Tetramethylammonium hydroxide (TMAH) developer was immersed for 60 seconds for development to form a fine resist pattern, and then the optimal exposure energy (Eop) was measured.

For comparison, Eop was measured after the same method as described above was performed to form a fine resist pattern except that the compound of the following Chemical Formula 21 was used instead of the resist polymer prepared in Synthesis Example 3 of the polymer.

(In the formula, the molar ratio a: b: c: d of each repeating unit is 0.1: 0.4: 0.4: 0.1)

As a result of the experiment, in the case of the polymer (ix) prepared in Synthesis Example 3 of the polymer, Eop was 17 mJ. Conversely, Eop of the polymer of the chemical formula 21 used as a comparative example was 31 mJ. From these experimental results, it can be seen that when the polymer according to the present invention is used, sulfonic acid is formed secondaryly after the acid is generated by light, thereby effectively improving the sensitivity.

The preferred embodiments of the present invention have been described in detail above, but the scope of protection of the present invention is not limited thereto. Various modifications and improvements made by a person of ordinary skill in the art using the basic concepts of the present invention described in the scope of the patent application are all It belongs to the protection scope of the present invention.

Claims (10)

An onium salt compound having a structure of the following Chemical Formula 1, In the chemical formula 1, R ₁ is selected from a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and A + is an organic cation having a structure of the following chemical formula 2, An acid enhancer as a polymer having a repeating unit having the structure of Chemical Formula 9 below, Chemical Formula 9 In the chemical formula 9, R ₁ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, A + is an organic cation having a structure of the following chemical formula 2, and q represents 1, The acid enhancer according to item 2 of the scope of patent application, which is a polymer having a structure of the following Chemical Formula 11, In the chemical formula 11, R ₁ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and A + is an organic cation having a structure of the following chemical formula 2, In the chemical formula 2, R _4a to R _4c are each independently selected from a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and at least one hydrogen is replaced by a halogen atom. In the group consisting of halogenated alkyl groups and combinations thereof, R _5a to R _5c are each independently selected from a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a heteroalkyl group having 1 to 20 carbon atoms, A cycloalkyl group having 3 to 30 carbon atoms, a heterocycloalkyl group having 2 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 3 to 30 carbon atoms, and their In the group formed by the combination, W is a repeating unit derived from an olefinic compound or a heterocycloalkyl compound, l, m, n, o, and p respectively represent the number of repeating units in the main chain, l + m + n + o + p = 1, 0 l / (l + m + n + o + p) <0.3, 0 m / (l + m + n + o + p) <0.99, 0 n / (l + m + n + o + p) <0.99, 0 o / (l + m + n + o + p) <0.99 and 0 <p / (l + m + n + o + p) 0.3. The acid enhancer according to item 2 of the scope of the patent application, wherein the acid enhancer is selected from the group consisting of compounds having structures of Chemical Formulae 11-1 to 11-8 and Chemical Formulae 11-21, In the chemical formulae 11-1 to 11-8 and the chemical formulae 11-21, R ₁ is a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R _4a to R _4c are each independently selected from a hydrogen atom, A group consisting of an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, a halogenated alkyl group having at least one hydrogen substituted with a halogen atom, and combinations thereof, and l, m, n , O and p respectively represent repeating units in the main chain, l + m + n + o + p = 1, 0 l / (l + m + n + o + p) <0.3, 0 m / (l + m + n + o + p) <0.99, 0 n / (l + m + n + o + p) <0.99, 0 o / (l + m + n + o + p) <0.99 and 0 <p / (l + m + n + o + p) 0.3. The acid enhancer according to item 2 of the scope of application for a patent, wherein the acid enhancer has a weight average molecular weight of 1000 g / mol to 100,000 g / mol in terms of polystyrene in terms of gel permeation chromatography. The acid enhancer according to item 2 of the scope of patent application, wherein the molecular weight distribution of the ratio of the weight average molecular weight to the number average molecular weight (Mw / Mn) of the acid enhancer is 1 to 3. A resist composition containing the acid enhancer according to item 2 of the patent application scope. The resist composition according to item 7 of the scope of the patent application, wherein the content of the acid enhancer is from 0.05% by weight to 5% by weight relative to the total weight of the resist composition. A method for forming a resist pattern, comprising the steps of: coating a resist composition according to item 7 of the patent application scope on a substrate to form a resist film; and after heat-treating the resist film, A step of exposing in a predetermined pattern; and a step of developing the exposed resist pattern. The method for forming a resist pattern according to item 9 of the scope of the patent application, wherein the exposure step uses a material selected from the group consisting of KrF excimer laser, ArF excimer laser, extreme ultraviolet laser, X-ray and electron beam. Implemented in groups of light sources.