KR101158024B1 - Polymer for photoresist and photoresist composition including the same - Google Patents

Abstract

Disclosed are a photoresist polymer and a photoresist composition comprising the same, polymerized using a monomer represented by the following formula. The polymer and photoresist composition has a low activation energy of a reaction in which a spiro cyclic ketal norbornene group is deprotected, thereby improving resolution and process margin, and having a low post-exposure bake temperature sensitivity (PEB sensitivity). It can be implemented and improves the depth of focus margin and line edge roughness.

In the above formula, R ^* and R ^** are hydrogen or methyl group, x and y are 1, 2 or 3, R is mono-cyclic or multi-cyclic having 3 to 50 carbon atoms Homo or hetero saturated hydrocarbon groups.

Line Edge Roughness, Photoresist

Description

Polymer for photoresist and photoresist composition comprising same {Polymer for photoresist and photoresist composition including the same}

1 to 6 are electron scanning micrographs of photoresist patterns each formed using a photoresist composition according to an embodiment of the present invention.

The present invention relates to a photoresist polymer and a photoresist composition comprising the same. More specifically, the activation energy of the reaction in which the spiro cyclic ketal norbornene group is deprotected is low, so that the resolution, process margin, etc. can be improved. It relates to a photoresist polymer having a spiro cyclic ketal norbornene group and a photoresist composition comprising the same.

In recent years, with the high integration and high precision of semiconductor devices, the formation of ultra-fine photoresist patterns of less than 90 nm in pitch is required in a photo lithography process. Accordingly, while the wavelength of the mass production exposure source is shortened to less than 193 nm, the development of technology for further optimizing and precision of the wafer processing process is in progress. In order to realize such a precise pattern, a photosensitive material having low line edge roughness, low post exposure baking sensitivity and low dry etching resistance is required.

A protecting group, which is attached to the side chain of the photoresist polymer and suppresses dissolution in basic solution, in order to improve resolution and process margin and to form a more precise pattern in the process of forming a photoresist pattern. It is preferable to lower the activation energy of the reaction to be deprotected or to use a material having a low post-exposure bake temperature sensitivity. That is, polyacrylates, cycloolefin-maleic anhydride copolymers, and polynorbornene, which are polymers for photoresists used in an ArF exposure source, have high levels of activation energy of a reaction in which a protecting group attached to the side chain of the polymer is deprotected. Iii) a polymer having a high activating energy protecting group such as tertiary butyl group, ii) a polymer having a neutral activating energy protecting group such as methyladamantyl group or ethyl adamantyl group, iii) a low acetal group or a ketal norbornene group It can be classified into a polymer having an activating energy protecting group. By using the polymer of i), an excellent pattern can be obtained.

As a photoresist polymer used in an exposure source of ArF, poly (meth) acrylate having an acetal group as a low activation energy protecting group is disclosed in U.S. Patent No. 4,975,519, U.S. Patent Application Publication No. 2002-0143130 (2002.10.03) and International Patent Although disclosed in WO 2002-20214 (2002.3.14) and the like, a (meth) acrylate polymer having a spiro cyclic ketal norbornene group as a protecting group and a photoresist composition comprising the same are not disclosed.

Accordingly, an object of the present invention is to lower the activation energy of the reaction in which the protecting group is deprotected in order to produce a photosensitive resist that meets the conditions required by the exposure technique, to improve the resolution and process margin, and the post-exposure bake temperature sensitivity It is to provide a photoresist polymer and a photoresist composition comprising the same that can implement a precise pattern because it is low.

Another object of the present invention is to provide a photoresist polymer and a photoresist composition comprising the same, which can improve the depth of focus margin and line edge roughness.

Still another object of the present invention is to provide a monomer of the polymer, a method of manufacturing the same, and a method of forming a photoresist pattern using the photoresist composition.

In order to achieve the above object, the present invention provides a monomer having a spiro cyclic ketal norbornene group represented by the following formula (1).

In the above formula, R ^* and R ^** are hydrogen or methyl group, x and y are 1, 2 or 3, R is mono-cyclic or multi-cyclic having 3 to 50 carbon atoms Homo or hetero saturated hydrocarbon groups.

The present invention also provides a photoresist polymer having a spiro cyclic ketal norbornene group, including a repeating unit represented by the following formula (2).

In Formula 2, R ^* , R ^** , R, x and y are as defined in Formula 1.

The present invention also provides a photoresist composition comprising the polymer and a method of forming a photoresist pattern using the photoresist composition.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The monomer of the photoresist polymer having a spiro cyclic ketal norbornene group according to the present invention is represented by the following formula (1).

[Formula 1]

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이다. In Formula 1, R ^* and R ^** is a hydrogen or methyl group, x and y is 1, 2 or 3, R is a monocyclic (cyclic) or multi-cyclic (polycyclic) having 3 to 50 carbon atoms of

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to be.

The monomer having a spiro cyclic ketal norbornene group represented by Formula 1 according to the present invention may be prepared by a conventional organic synthesis method. For example, first, as shown in Scheme 1 below, cyclic ketal alcohol is prepared by reacting cyclic ketone with trialcohol under an acid catalyst.

In Scheme 1, R, x and y are as defined in Formula 1.

The acid catalyst may be used a wide range of acid catalysts commonly used, for example, may be used paratoluene sulfonic acid. The reaction may be carried out in a commonly used organic solvent such as normal heptane for 1 to 24 hours at a temperature of 30 to 100 ℃ and atmospheric pressure in a nitrogen or argon atmosphere.

Next, spiro cyclic ketal acrylate can be prepared by reacting the prepared spiro cyclic ketal alcohol with (meth) acryloyl chloride under a base catalyst, as shown in Scheme 2 below.

In Scheme 2, R ^** , R, x and y are as defined in the formula (1).

The base catalyst can be used a wide range of commonly used base catalyst, for example triethylamine can be used. The reaction can be carried out in a conventionally used organic solvent such as tetrahydrofuran (THF) for 1 to 24 hours under an inert atmosphere such as nitrogen, argon, at a temperature of 0 to 60 ℃ and atmospheric pressure.

Next, when the spiro cyclic ketal acrylate prepared is reacted with (dimethyl) cyclopentadiene (Diels-Alder) as in Scheme 3 below, the monomer represented by Chemical Formula 1 may be prepared.

In Scheme 3, R ^* , R ^** , R, x and y are as defined in the formula (1).

The photoresist polymer having a spiro cyclic ketal norbornene group according to the present invention includes a repeating unit represented by the following formula (2).

[Formula 2]

In Formula 2, R ^* , R ^** , R, x and y are as defined in Formula 1.

In addition, according to the present invention, a photoresist polymer may be represented by the following Chemical Formula 3, and a preferable example is a polymer represented by the following Chemical Formulas 3a to 3f.

In Formulas 3 and 3a to 3f, R ^* and R ^** are each independently hydrogen or a methyl group, R ₁ and R ₂ are a chain or cyclic alkyl group having 1 to 20 carbon atoms, and R is 3 to 50 carbon atoms. Mono- or multi-cyclic homo or hetero saturated hydrocarbon groups, x and y are 1, 2, or 3, a, b, and c are repeating units constituting the polymer The molar percentage of 1 to 95 mol%: 1 to 95 mol%: 1 to 95 mol%, respectively.

The spiro cyclic ketal norbornene group, which is a bulky saturated hydrocarbon, attached to the side chain of the photoresist polymer according to the present invention, serves to prevent the polymer and the photoresist composition including the same from being dissolved in a basic solution such as a basic developing solution. As a protecting group, deprotected by an acid catalyst (H +) generated in the photoacid generator of the exposed portion, and increases the solubility of the exposed portion to increase the contrast of the photoresist composition, in particular the spiro cyclic ketal norbornene Since the group has a low activation energy of the deprotection reaction, it is possible to improve the resolution of the resist pattern, the energy process margin, and the like, and since the product of the deprotection reaction is a bulky material of high molecular weight, the depth of focus margin and the line edge roughness Can be improved.

The polymer for a photoresist composition having a spiro cyclic ketal norbornene group represented by Formula 3 according to the present invention may be prepared by a conventional polymerization reaction, for example, a) the monomer represented by Formula 1 and the following The monomer and maleic anhydride represented by the formulas (4) and (5) are dissolved in a polymerization solvent, b) a polymerization initiator is added to the mixture solution, and c) the mixture solution to which the initiator is added is added in a nitrogen or argon atmosphere at 60 to It may be prepared by reacting at 70 ° C. for 4 to 24 hours. Preferably, the polymerization may be carried out by radical polymerization, solution polymerization, bulk polymerization or polymerization using a metal catalyst. In addition, the preparation method may include the step of purifying the reaction product using a lower alcohol containing diethyl ether, hexane, petroleum ether, methanol, ethanol or isopropanol, water, a mixture thereof, and the like. It may also include.

In Chemical Formulas 4 and 5, R *, R **, R ₁ and R ₂ are the same as defined in Chemical Formula 3.

The monomer represented by Chemical Formula 1, the Chemical Formulas 4, 5, and maleic anhydride may be polymerized as in Scheme 4 to prepare a photoresist polymer represented by Chemical Formula 3.

In Scheme 4, R ^* , R ^** , R ₁ , R ₂ , R, x, y, a, b, and c are as defined in Chemical Formula 3.

As the polymerization solvent of the polymerization reaction, a polymerization solvent commonly known in the art may be widely used, but is not limited to cyclohexanone, cyclopentanone, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, dioxane, Methyl ethyl ketone, benzene, toluene, xylene, or mixtures thereof may be exemplified, and the polymerization initiator may also be widely used as polymerization initiators commonly known in the art, but is not limited to benzoyl peroxide, 2, 2'-azobisisobutyronitrile (AIBN), acetylperoxide, lauryl peroxide, t-butylperacetate, t-butylhydroperoxide, di-t-butylperoxide or mixtures thereof have. The photosensitive polymers of Formulas 2 to 3 preferably have a weight average molecular weight of 3,000 to 100,000 and a degree of dispersion of 1.0 to 5.0. When the weight average molecular weight and the dispersion degree are outside the above ranges, the physical properties of the photoresist film may be reduced, or the formation of the photoresist film may be difficult, and the contrast of the pattern may be lowered.

 The photoresist composition according to the present invention includes a photosensitive polymer including a repeating unit represented by Chemical Formula 2, a photoacid generator for generating an acid, and an organic solvent, and may further include various additives as necessary. The content of the photosensitive polymer including the repeating unit represented by Formula 2 is preferably 1 to 30% by weight based on the total photoresist composition, and more preferably 5 to 15% by weight. If the content of the photosensitive polymer is less than 1% by weight, the resist layer remaining after coating is too thin to form a pattern having a desired thickness, and if it exceeds 30% by weight, coating uniformity may be degraded.

The photoacid generator generates an acid component such as H ⁺ by exposure to decomposes the protecting group of the photosensitive polymer, and may be used as a compound capable of generating an acid by light. Sulfonic acid compounds such as sulfonic acid, onium salt compounds such as onium salts, and mixtures thereof. Non-limiting examples of photoacid generators include phthalimidotrifluoromethane sulfonate, dinitrobenzyltosylate, n-decyl disulfone, nap having low absorbance at 157 nm and 193 nm. Naphthylimido trifluoromethane sulfonate, diphenyluredo hexafluorophosphate, diphenyluredo salt hexafluoro arsenate, diphenyluredo salt hexafluoro antimonate, diphenylparamethoxyphenylsulfonium Triflate, Diphenylparatoluenylsulfonium Triflate, Diphenylparaisobutylphenylsulfonium Triflate, Triphenylsulfonium Hexafluoro Arsenate, Triphenylsulfonium Hexafluoro Antimonate, Triphenylsulfonium Triflate, dibutylnaphthylsulfonium triflate, and mixtures thereof. The content of the photoacid generator is preferably 0.05 to 10% by weight based on the photoresist polymer. If it is less than 0.05% by weight, the sensitivity of the photoresist composition to light decreases, which may make it difficult to deprotect the protecting group. If it exceeds 10% by weight, the photoacid generator absorbs a lot of ultraviolet rays and generates a large amount of acid, thereby causing There is a fear that the cross section becomes poor.

As the organic solvent constituting the remaining components of the photoresist composition according to the present invention can be used a wide variety of organic solvents commonly used in the preparation of the photoresist composition, non-limiting examples include ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, propylene glycol, propylene glycol monoacetate, toluene, xylene, methyl ethyl ketone, Methyl isoamyl ketone, cyclohexanone, dioxane, methyl lactate, ethyl lactate, methyl pyruvate, ethyl pyruvate, methyl methoxy propionate, ethyl ethoxy propionate, N, N-dimethylformamide , N, N-dimethylacetamide, N-methyl 2-pyrrolidone, 3-ethoxye Propionate, 2-heptanone, gamma-butyrolactone, 2-hydroxypropionethyl, 2-hydroxyethyl 2-methylpropionate, ethyl ethoxy acetate, ethyl hydroxyacetate, 2-hydroxy 3-methylpart Methyl carbonate, 3-methoxy 2-methylpropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxy 2-methylpropionate, ethyl acetate, butyl acetate and mixtures thereof.

In addition, the photoresist composition according to the present invention may further include an organic base as needed, non-limiting examples of the organic base is triethylamine, triisobutylamine, triisooctylamine, diethanolamine, triethanol Amines and mixtures thereof can be exemplified. The content of the organic base is preferably 0.01 to 2.00 wt% based on the total photoresist composition. If the content of the organic base is less than 0.01% by weight, a t-top phenomenon may occur in the resist pattern, and if the content exceeds 2.00% by weight, the sensitivity of the photoresist composition may be lowered, thereby lowering the process progress rate.

The photoresist composition according to the present invention may be prepared by mixing the photosensitive polymer, the photoacid generator, the organic solvent, and various additives as necessary, and filtering by a filter as necessary, wherein, based on 100 parts by weight of the total photoresist It is preferable to make solid content concentration into 10 to 60 weight%. When the concentration of the solid content is less than 10% by weight, the resist layer remaining after coating is too thin to form a pattern having a desired thickness, and when it exceeds 60% by weight, coating uniformity may be deteriorated.

In order to form a photoresist pattern using the photoresist composition according to the present invention, first, the photoresist composition is applied to a substrate such as a silicon wafer or an aluminum substrate using a spin coater to form a photoresist film. After exposing the photoresist film to a predetermined pattern, and then forming the photoresist pattern by a conventional photolithography process in which the exposed photoresist pattern is heated after exposure and developed, a semiconductor device having a desired pattern can be provided. As the developer used in the developing step, an alkaline aqueous solution in which alkaline compounds such as sodium hydroxide, potassium hydroxide, sodium carbonate and tetramethylammonium hydroxide (TMAH) are dissolved at a concentration of 0.1 to 10% by weight may be used. Accordingly, an appropriate amount of a water-soluble organic solvent such as methanol and ethanol and a surfactant may be added to the developer. In addition, after the development process, the cleaning process may be further performed to clean the substrate with ultrapure water.

Hereinafter, the present invention will be described in more detail with reference to specific examples. The following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by the following examples.

Example 1-1 Preparation of Monomer represented by Chemical Formula 6a

To a 500 mL three-neck round bottom flask, 24.0 g (0.26 mol) of glycerol, 9.8 g (0.1 mol) of cyclopentane-1,3-dione, and 0.15 g of paratoluenesulphonic acid were added, and 60 g of normal heptane was added thereto. An Edinstark trap was installed and the reaction was carried out at reflux for 12 hours at 98 ° C. under a nitrogen atmosphere. After the reaction was completed, the reaction was cooled to room temperature, the cooled reaction was placed in a separatory funnel, the layered unreacted polyol was removed, and the spiro cyclic ketal alcohol obtained by removing the polyol was purified using column chromatography. It was. Purified spiro cyclic ketal alcohol was placed in a three-necked round bottom flask and diluted by addition of 30 g of tetrahydrofuran (THF). To the diluted reaction solution, a mixture of acryloyl chloride (18.2 g) and 50 g of tetrahydrofuran was added using a dropping funnel. 10 mL of triethylamine was added thereto, and the reaction was performed under reflux for 12 hours in a nitrogen atmosphere. After the reaction was completed, the solvent was removed under reduced pressure, and the reaction product was separated using liquid chromatography (silica gel, hexane: ether = 6: 1), and then the solvent was removed again. After the solvent was removed, the reaction product was recrystallized with hexane, and the mixture was left at room temperature to obtain a diacrylate intermediate. The monomer represented by the following Chemical Formula 6a was subjected to a Diels-Alder reaction with 6.6 g (0.1 mol) of cyclopentadiene. Was obtained in a yield of 55% {H-NMR: s (5.60, 4H), m (4.56, 2H), m (4.41, 4H), m (4.21, 2H), m (3.63, 2H), m (2.37) , 6H), m (1.96, 14H)}.

Example 1-2 Preparation of Monomer Represented by Formula 6b

50% of the crosslinking monomer represented by the following formula (6b) in the same manner as in Example 1-1, except that 11.2 g of cyclohexane-1,4-dione was used instead of 9.8 g of cyclopentane-1,3-dione. Yield of {H-NMR: s (5.65, 4H), m (4.66, 2H), m (4.54, 4H), m (4.31, 2H), m (3.93, 2H), m (2.21, 6H) , m (1.66, 16H)}.

Example 1-3 Preparation of Monomers Represented by Formula 6c

Same as Example 1-1 except that 16.6 g of 1,5-dimethylbicyclo [3,3,0] octane-3,7-dione was used instead of 9.8 g of cyclopentane-1,3-dione. By the method, the monomer represented by the following Chemical Formula 6c was obtained in a yield of 60%. {H-NMR: s (5.60, 4H), m (4.56, 2H), m (4.41, 4H), m (4.21, 2H), m (3.63, 2H), m (2.37, 6H), m (1.96, 22H)}.

Example 1-4 Preparation of a Monomer Represented by Chemical Formula 6d

Except for using 9.8g of cyclopentane-1,3-dione, 75.2-dimethylnorbornane-2,3-dione was used in the same manner as in Example 1-1 except that 15.2g The monomer was obtained in a yield of 45% {H-NMR: s (5.63, 4H), m (4.79, 2H), m (4.51, 4H), m (4.25, 2H), m (3.93, 2H), m ( 2.57, 6H), m (1.43, 18H)}.

Example 1-5 Monomer Preparation represented by Chemical Formula 6e

45% of the monomer represented by the following Chemical Formula 6e in the same manner as in Example 1-1 except that 16.4 g of adamantane-2,6-dione was used instead of 9.8 g of cyclopentane-1,3-dione Yielded {H-NMR: s (5.57, 4H), m (4.96, 2H), m (4.57, 4H), m (4.41, 2H), m (3.83, 2H), m (2.68, 6H) , m (1.53, 20H)}.

Example 1-6 Preparation of Monomer Expressed by Chemical Formula 6f

Monomer represented by the following formula (6f) in the same manner as in Example 1-1, except that 23.6 g of 2,2-bis-4-carbonylcyclohexyl propane was used instead of 9.8 g of cyclopentane-1,3-dione Was obtained in a yield of 35% {H-NMR: s (5.45, 4H), m (4.66, 2H), m (4.49, 4H), m (4.11, 2H), m (3.54, 2H), m (2.23 , 6H), m (1.56, 30H)}.

Example 2-1 Preparation of Polymer Represented by Chemical Formula 3a

46.2 g (0.1 mol) of monomers (R ^* , R ^** = hydrogen groups) represented by Chemical Formula 6a in the reactor, 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, 4.9 g of maleic anhydride ( 0.05 mol), 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate and 0.7 g of azobis (isobutyronitrile) (AIBN) were added, and the reaction was dissolved in 25 g of anhydrous THF, and then frozen. The gas was removed using an ampoule as a method, and the degassed reactant was polymerized at 68 ° C. for 24 hours. After the polymerization was completed, was precipitated slowly added dropwise to the reaction in an excess of diethyl ether, it was dissolved in re-THF, to the dissolved reaction product was reprecipitated in diethyl ether polymer represented by the formula 3a (R ^* , R ^** = hydrogen or methyl group, x = 1, y = 1).

Example 2-2 Preparation of the Polymer Represented by Chemical Formula 3b

47.6 g (0.1 mol) of monomer (R ^* , R ^** = hydrogen group) represented by Chemical Formula 6b, 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, and 4.9 g (0.05 mol) of maleic anhydride ), Except that 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate was used, and the polymer represented by Chemical Formula 3b in the same manner as in Example 2-1 (R ^* , R ^** = Hydrogen or a methyl group, x = 1, y = 1).

Example 2-3 Preparation of Polymer Represented by Chemical Formula 3c

53.2 g (0.1 mol) of monomer (R ^* , R ^** = hydrogen group) represented by Chemical Formula 6c, 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, and 4.9 g (0.05 mol) of maleic anhydride ), A polymer represented by the formula (3c) in the same manner as in Example 2-1, except that 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate was used (R ^* , R ^** = Hydrogen or a methyl group, x = 1, y = 1).

Example 2-4 Preparation of the Polymer Represented by Chemical Formula 3d

51.6 g (0.1 mol) of monomers represented by Formula 6d (R ^* , R ^** = hydrogen group), 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, and 4.9 g (0.05 mol) of maleic anhydride ), A polymer represented by Chemical Formula 3d in the same manner as in Example 2-1, except that 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate was used (R ^* , R ^** = Hydrogen or a methyl group, x = 1, y = 1).

Example 2-5 Preparation of the Polymer Represented by Chemical Formula 3e

52.8 g (0.1 mol) of monomers represented by Formula 6e (R ^* , R ^** = hydrogen group), 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, and 4.9 g (0.05 mol) of maleic anhydride ), A polymer represented by Chemical Formula 3e in the same manner as in Example 2-1, except that 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate was used (R ^* , R ^** = Hydrogen or a methyl group, x = 1, y = 1).

Example 2-6 Preparation of the Polymer Represented by Chemical Formula 3f

57.1 g (0.1 mol) of monomer (R ^* , R ^** = hydrogen group) represented by Chemical Formula 6f, 6.5 g (0.05 mol) of 2-hydroxyethyl methacrylate, and 4.9 g (0.05 mol) of maleic anhydride ), Except that 22.2 g (0.1 mol) of 2-methyl-2-adamantyl methacrylate was used, and the polymer represented by Chemical Formula 3f was the same as that of Example 2-1 (R ^* , R ^** = Hydrogen or a methyl group, x = 1, y = 1).

[Examples 3-1 to 3-6] Preparation of a photoresist composition comprising the polymer prepared in Examples 2-1 to 2-6

2 g of the polymer prepared in Example 2-1, 0.024 g of phthalimidotrifluoromethanesulfonate and 0.06 g of triphenylsulfonium triflate were dissolved in 20 g of propylene glycol methyl ethyl acetate, and then filtered through a 0.20 μm filter to obtain a photoresist. The composition was prepared, and a photoresist composition was prepared in the same manner except for using 2 g of the polymer prepared in Examples 2-2 to 2-6, instead of 2 g of the polymer prepared in Example 2-1.

[Examples 4-1 to 4-6] Exposure pattern formation using photoresist composition

After spin-coating the photoresist composition prepared in Examples 3-1 to 3-6 on the etched layer of the silicon wafer to prepare a photoresist thin film, soft bake for 90 seconds in an oven or hot plate at 90 ° C, After exposure with an ArF laser exposure equipment, the substrate was heated again at 120 ° C. for 90 seconds. The heated wafer was immersed in a 2.38 wt% TMAH aqueous solution for 40 seconds to develop, thereby forming a L / S pattern of 0.07 μm. Physical properties of the formed photoresist pattern are shown in Table 1 below, and electron scanning micrographs of the photoresist patterns formed using the compositions prepared in Examples 3-1 to 3-6 are shown in FIGS. 1 to 6, respectively.

Resist
Composition at least
definition
[μm] Depth of focus
[μm] Line edge
Roughness
[nm] energy
Process Margin [%] Post-exposure Bake Temperature Stability
[nm / ℃]
Dry etching resistance Example 3-1 0.065 0.40 7.5 13.0 4.5 Very good Example 3-2 0.065 0.40 5.8 12.5 3.5 Very good Example 3-3 0.065 0.45 5.3 13.5 1.5 Very good Example 3-4 0.065 0.35 5.0 15.5 1.5 Very good Example 3-5 0.065 0.45 5.4 14.5 One Very good Examples 3-6 0.065 0.45 5.8 11.0 One Very good

The photoresist polymer and the photoresist composition comprising the same according to the present invention have a low activation energy for the reaction in which the spiro cyclic ketal norbornene group is deprotected, thereby improving the resolution and process margin of the resist pattern. In addition, since it has high dry etching stability and stable post-exposure bake temperature stability, there is an advantage that a precise pattern can be realized. In addition, the photoresist polymer and the photoresist composition including the same have the advantage of improving the depth of focus margin and line edge roughness of the resist film.

Claims (11)

Monomer represented by following formula (1). [Formula 1]

In Formula 1, R ^* and R ^** is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic (carbon-cyclic) having 3 to 50 carbon atoms Is a homo or hetero saturated hydrocarbon group. The method of claim 1, wherein R is

,

,

,

,

,

,

,

,

,

,

, or

Monomer selected from the group consisting of. The monomer of claim 1, wherein the monomer is prepared by reacting a cyclic ketone with a trialcohol under an acid catalyst. A photoresist polymer comprising a repeating unit represented by the following formula (2). [Formula 2]

In Formula 2, R ^* and R ^** is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic (carbon-based) having 3 to 50 carbon atoms Is a homo or hetero saturated hydrocarbon group. The polymer for photoresist according to claim 4, wherein the photoresist polymer is represented by the following Chemical Formula 3. (3)

In Formula 3, R ^* and R ^** are each independently hydrogen or a methyl group, R ₁ and R ₂ are a chain or cyclic alkyl group having 1 to 20 carbon atoms, R is a monocyclic (mono having 3 to 50 carbon atoms) -cyclic or multi-cyclic homo or hetero saturated hydrocarbon group, x and y are 1, 2 or 3, and a, b and c are mole% of repeating units constituting the polymer. 1-95 mol%: 1-95 mol%: 1-95 mol%, respectively. The photoresist polymer of claim 4, wherein the photoresist polymer is selected from the group represented by the following Chemical Formulas 3a to 3f. [Chemical Formula 3]

(3b)

[Formula 3c]

[Formula 3d]

[Formula 3e]

[Formula 3f]

In Formulas 3a to 3f, R ^* and R ^** are each independently hydrogen or a methyl group, R ₁ and R ₂ are a chain or cyclic alkyl group having 1 to 20 carbon atoms, and x and y are 1, 2, or 3, and a, b, and c are 1 to 95 mol%: 1 to 95 mol%: 1 to 95 mol%, respectively, as mol% of the repeating units constituting the polymer. A polymer comprising a repeating unit represented by the formula (2) [Formula 2]

In Formula 2, R ^* and R ^** is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic (carbon-based) having 3 to 50 carbon atoms Is a homo or hetero saturated hydrocarbon group of; Photoacid generators generating acid; And Photoresist composition comprising an organic solvent. The photoresist composition of claim 7, wherein the photoresist composition comprises 1 to 30 wt% of the polymer based on the total photoresist composition, 0.05 to 10 wt% of the photoacid generator and the remaining organic solvent based on the polymer. The method of claim 7, wherein the photoacid generator is phthalimidotrifluoromethanesulfonate, dinitrobenzyltosylate, n-decyldisulfone, naphthylimidotrifluoromethanesulfonate, diphenyl iodo salt hexafluorophosphate, Diphenylurodoxyl hexafluoro arsenate, diphenylurodoxyl hexafluoro antimonate, diphenylparamethoxyphenylsulfonium triflate, diphenylparatoluenylsulfonium triflate, diphenylparaisobutylphenylsulfonium tri Plates, triphenylsulfonium hexafluoro arsenate, triphenylsulfonium hexafluoro antimonate, triphenylsulfonium triflate, dibutylnaphthylsulfonium triflate and mixtures thereof Phosphorus photoresist composition. The method of claim 7, wherein the organic solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoethyl ether, propylene glycol monomethyl ether acetate , Propylene glycol, propylene glycol monoacetate, toluene, xylene, methyl ethyl ketone, methyl isoamyl ketone, cyclohexanone, dioxane, methyl lactate, ethyl lactate, methyl pyruvate, ethyl pyruvate, methyl methoxy Propionate, ethylethoxy propionate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl 2-pyrrolidone, 3-ethoxyethylpropionate, 2-heptanone, Gamma-butyrolactone, 2-hydroxypropionethyl, 2-hydroxyethyl 2-methylpropionate, ethyl ethoxy acetate, ethyl hydroxyacetate, 2-hydroxy 3-methylbutanoic acid For photoresist selected from the group consisting of methyl, 3-methoxy 2-methylpropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxy 2-methylpropionate, ethyl acetate, butyl acetate and mixtures thereof Composition. A photoresist polymer comprising a repeating unit represented by Formula 2 below; Photoacid generators generating acid; And applying a photoresist composition comprising an organic solvent to the substrate to form a photoresist film, [Formula 2]

In Formula 2, R ^* and R ^** is hydrogen or a methyl group, x and y are 1, 2 or 3, R is a mono-cyclic or multi-cyclic (carbon-based) having 3 to 50 carbon atoms Is a homo or hetero saturated hydrocarbon group of; And Exposing the photoresist film in a predetermined pattern; and then heating and developing the exposed photoresist pattern after exposure.

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