KR20070076608A - Compound for photoresist, photoresist composition having the compound and method of forming a photoresist pattern using the photoresist composition - Google Patents

Abstract

Provided are a photoresist compound for producing a fine pattern and reducing roughness of linewidth, a photoresist composition having the same compound and a method for forming a photoresist pattern using the photoresist composition. The photoresist compound is represented by the formula(1) or (2). In the formulae, R1 is a residue of a triol compound in which a hydrogen atom of hydroxyl group is removed, R2, R3 and R4 are residues of a dicarboxylic acid compound in which a hydrogen atom of carboxy group is removed, R5, R6 and R7 are independently t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, X1 to X6 are independently hydrogen atom or hydroxyl group, R8 is a residue of tricarboxylic acid compound in which hydrogen atom of a carboxyl group is removed. The photoresist composition comprises a non-linear low molecular weight compound, a photoresist and an organic solvent. The photoresist composition can produce a fine pattern with a resolution of a molecular level due to small building block size.

Description

Compound for photoresist, photoresist composition comprising the same and method for forming photoresist pattern using same {COMPOUND FOR PHOTORESIST, PHOTORESIST COMPOSITION HAVING THE COMPOUND AND METHOD OF FORMING A PHOTORESIST PATTERN USING THE PHOTORESIST COMPOSITION}

1 and 2 are schematic diagrams for explaining a photoresist pattern formed using a conventional photoresist composition comprising a polymer.

3 to 5 are cross-sectional views illustrating a method of forming a photoresist pattern according to an embodiment of the present invention.

6 and 7 are schematic diagrams for explaining the photoresist pattern formed using the photoresist composition according to the present invention.

8 is an electron micrograph showing a photoresist pattern formed using the photoresist composition according to the embodiment.

Explanation of symbols on the main parts of the drawings

100 substrate 200 photoresist film

220: photoresist pattern 300: mask

The present invention relates to a compound for photoresist, a photoresist composition and a method of forming a photoresist pattern. More specifically, the present invention relates to a compound that can be used to form a photoresist pattern in a semiconductor manufacturing process, a photoresist composition containing the compound, and a method of forming a photoresist pattern using the same.

In recent years, with the rapid spread of information media such as computers, semiconductor devices are also rapidly developing. In terms of its function, the semiconductor device is required to operate at a high speed and to have a large storage capacity. In response to these demands, manufacturing techniques have been developed in the direction of improving the degree of integration, reliability, response speed and the like of the semiconductor device. In particular, the demand for microfabrication techniques such as a photolithography process is becoming strict as a main technique for improving the integration degree of the semiconductor device.

In the photolithography process, a photoresist pattern is formed using a photoresist composition. In general, the photoresist composition is prepared by mixing a photoresist that generates an acid in response to light, a polymer having a structure that reacts sensitively to an acid, a solvent, and the like. The photoresist composition has a property of changing solubility in a developer when exposed to light. Therefore, after the photoresist composition is coated and exposed, the exposed portion may be developed to form a photoresist pattern having a desired shape.

As the pattern included in the semiconductor device is gradually finer, the line width of the pattern is approaching to the size of the polymer itself included in the photoresist composition. The polymer has a large molecule size due to its nature, and thus has a large building block forming a photoresist pattern.

1 and 2 are schematic diagrams for explaining a photoresist pattern formed using a conventional photoresist composition comprising a polymer.

1 and 2, when the photoresist pattern is formed using the photoresist composition including the polymer described above, the line block of the formed photoresist pattern is very rough and its thickness is not uniform due to the large building block. It is therefore not suitable for forming fine patterns with molecular resolution.

In addition, the polymer has various molecular weights, that is, various sizes and have a structure in which molecules are entangled with each other. In addition, the polymer swells easily during the development process, and the solubility in the developer is not constant according to the molecular weight. Therefore, when the photoresist pattern is formed using the photoresist composition including the polymer, line width roughness (LWR) is further increased during the development process, and there is a limit in clearly forming a fine pattern.

Therefore, the development of a photoresist composition capable of reducing the size of the building blocks constituting the photoresist pattern, forming a fine pattern of high resolution, and reducing the roughness of the line width is required.

Accordingly, an object of the present invention is to provide a compound for photoresist that can realize high resolution and reduce roughness of line width.

Another object of the present invention is to provide a photoresist composition comprising the compound described above.

Still another object of the present invention is to provide a method of forming a photoresist pattern using the photoresist composition described above.

Compound for a photoresist of the present invention according to an embodiment for achieving the above object of the present invention is represented by the following formula (1) or (2).

...... (1)

...... (One)

...... (2)

...... (2)

In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, and X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group. In addition, in said Formula 2, R <_8> represents the residue from which the hydrogen atom of the carboxy group was removed from the tricarboxylic acid compound. Examples of the triol compound include glycerol or cyclohexanetriol, and examples of the dicarboxylic acid compound include glutaric acid, succinic acid, or 3,3-tetra. Methylene glutaric acid (3,3-tetramethyleneglutaric acid). In addition, examples of the tricarboxylic acid include 1,3,5-cyclohexanetricarboxylic acid (1,3,5-cyclohexanetricarboxylic acid).

A photoresist composition according to an embodiment for achieving the above object of the present invention includes a compound for a photoresist, a photosensitizer and an organic solvent represented by the formula (1) or (2). The photoresist composition may include about 8 wt% to about 20 wt% of the photoresist compound represented by Formula 1 or 2, about 0.1 wt% to about 0.5 wt% of the photoresist, and an extra organic solvent. Examples of the photosensitizer include sulfonium salts and triamylsulfonium salts. Examples of the organic solvent include propylene glycol methyl ether acetate and ethyl lactate. In addition, the photoresist composition may further include an organic base such as triethylamine and triisobutylamine. In this case, the photoresist composition is about 8 to about 20% by weight of the compound for the photoresist represented by the formula 1 or 2, about 0.1 to about 0.5% by weight of the photosensitizer, about 0.1 to about 5% by weight and the organic base It may include an organic solvent of.

In addition, in the method for forming a photoresist pattern according to an embodiment of the present invention for achieving another object of the present invention described above, a compound for photoresists, photosensitizers and organic solvents represented by the formula (1) or 2 on the object Applying a photoresist composition comprising a to form a photoresist film. After exposing the photoresist film, the photoresist film is partially removed to form a photoresist pattern.

The compound for photoresists according to the present invention can implement a fine pattern having a small resolution of the molecule size of the molecule. In addition, since the solubility in the developer is constant between the molecules of the compound and there is no chain entanglement phenomenon, it is possible to reduce the line width roughness (LWR).

Hereinafter, the photoresist compound of the present invention, a photoresist composition comprising the same, and a method of forming a photoresist pattern using the same will be described in detail.

Photoresist Compound

The compound for photoresists of the present invention is a nonlinear low molecule and has the following characteristics.

First, the compound, unlike the polymer, has a clear molecular structure and has a single molecular weight. Therefore, when the compound is used to form a photoresist pattern, the solubility in the developer is constant to reduce the line roughness (LWR). Second, since the size of the molecule is smaller than that of the polymer, a photoresist pattern having a molecular resolution can be realized. Third, the compound has a three-dimensional structure with a short radius of rotation of the molecule and there is no intermolecular interaction such as chain entanglement that occurs easily in linear polymers. Therefore, when the photoresist pattern is formed using the compound, the solubility difference between the exposed portion and the non-exposed portion may be increased in the developing process to clearly form the photoresist pattern, and the roughness of the line width may be reduced.

The compound for photoresists of the present invention is represented by the following formula (1) or (2).

...... (1)

...... (One)

...... (2)

...... (2)

In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydro pyranyl group or 1-ethoxyethyl group, and X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group. In addition, in said Formula 2, R <_8> represents the residue from which the hydrogen atom of the carboxy group was removed from the tricarboxylic acid compound.

In the compound for a photoresist according to an embodiment of the present invention, in Formula 1 R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from glycerol or cyclohexanetriol, R ₂ , R ₃ And R ₄ independently represents a residue from which a hydrogen atom of a carboxyl group has been removed from glutaric acid, succinic acid or 3,3-tetramethyleneglutaric acid. In addition, in Formula 2, R ₈ represents a residue in which a hydrogen atom of a carboxyl group is removed from 1,3,5-cyclohexanetricarboxylic acid.

Compounds for photoresists according to one embodiment of the present invention are represented by the following formulas 3 to 9.

...... (3)

...... (3)

...... (4)

...... (4)

...... (5)

...... (5)

...... (6)

(6)

...... (7)

(7)

...... (8)

...... (8)

...... (9)

(9)

In formulas 1 to 9, R ₅ , R ₆ and R ₇ are easily separated from the compound by reacting with hydrogen ions as acid-decomposable functional groups. Examples of R ₅ , R ₆ and R ₇ include a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group. R ₅ , R ₆ and R ₇ may be identical or different. In addition, X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group.

In the compound for photoresists according to the present invention, the compound represented by Formula 1 synthesizes a core including R ₁ , R ₂ , R _3, and R ₄ , and the compound represented by Formula 10 below It is prepared by reacting. In addition, the compound represented by Formula 2 is prepared by reacting the central portion including R ₈ with the compound represented by the following Formula 10.

...... (10)

...... (10)

In Formula 10, R ₉ represents a t-butyl group, a tetrahydropyranyl group or a 1-ethoxyethyl group, and X ₇ and X ₈ represent a hydrogen atom or a hydroxyl group.

In order to manufacture the compound for photoresist represented by the above formula 1, _first , a core including R ₁ , R ₂ , R _3, and R ₄ is synthesized. In the compound for photoresists represented by the formula (1), the central portion is synthesized by reacting a triol compound with a dicarboxylic acid compound. Examples of the triol compound include glycerol or cyclohexanetriol. Examples of the dicarboxylic acid compound include glutaric acid, succinic acid, or 3,3-tetramethylene glutaric acid. The central portion synthesized by reacting the triol compound with the dicarboxylic acid compound includes three carboxyl groups at its terminal.

For example, the center of the compound represented by Formula 3 may be synthesized by reacting glycerol and glutaric anhydride. The center of the compound represented by the formula 4 can be synthesized by reacting glycerol (glycerol) and succinic anhydride (succinic anhydride). The center of the compound represented by Formula 5 can be synthesized by reacting glycerol (glycerol) and 3,3-tetramethylene glutar anhydride (3,3-tetramethyleneglutaric anhydride).

In addition, the center of the compound represented by the formula 6 can be synthesized by reacting 1,3,5-trihydroxycyclohexane (glutaric anhydride) and 1,3,5-trihydroxycyclohexane. The center of the compound represented by Formula 7 can be synthesized by reacting 1,3,5-trihydroxycyclohexane and succinic anhydride. The center of the compound represented by the formula 8 is 1,3,5-trihydroxycyclohexane (1,3,5-trihydroxycyclohexane) and 3,3-tetramethyleneglutaric anhydride (3,3-tetramethyleneglutaric anhydride) It can be synthesized by reacting.

The center part of the compound for photoresists represented by said Formula 2 contains a tricarboxylic acid compound. Examples of the tricarboxylic acid compound include 1,3,5-cyclohexanetricarboxylic acid (1,3,5-cyclohexanetricarboxylic acid). When 1,3,5-cyclohexanetricarboxylic acid is used as the center, the compound is represented by Formula 9.

On the other hand, the compound represented by the formula 10 is a cholic acid (cholic acid), deoxycholic acid (deoxycholic acid) or lysocholic acid (lithocholic acid) t-butyl alcohol (tert-butyl alcohol), tetrahydropyranol ( It is synthesized by reacting with tetrahydropyranol) or 1-ethoxyethanol. Here, when collic acid is used, X ₇ and X ₈ both represent hydroxyl groups. When using deoxycholic acid, X ₇ represents a hydrogen atom and X ₈ represents a hydroxyl group. In the case of using lysoholic acid, X ₇ and X ₈ both represent hydrogen atoms.

The photoresist compound represented by Formula 1 or 2 is prepared by esterification of three carboxyl groups located at the terminal of the central portion and a hydroxyl group located at the terminal of the compound represented by Formula 10.

When the compound for photoresists according to the present invention is applied as a photoresist, the size of the molecule is small, it can implement a fine pattern having a molecular level resolution. In addition, since the solubility in the developer is constant and there is no entanglement of the chain, the roughness (LWR) of the line width can be reduced.

Photoresist composition

The photoresist composition according to the present invention includes a compound for photoresist, a photosensitizer and an organic solvent represented by the following formula (1) or (2).

...... (1)

...... (One)

...... (2)

...... (2)

In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydro pyranyl group or 1-ethoxyethyl group, and X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group. In addition, in said Formula 2, R <_8> represents the residue from which the hydrogen atom of the carboxy group was removed from the tricarboxylic acid compound. The photoresist compound represented by Formula 1 or 2 is as described above, and further detailed description is omitted.

When the photoresist composition of the present invention contains less than about 8% by weight of the compound represented by Formula 1 or 2 above, it is difficult to form a photoresist pattern having a sufficient thickness, which is not preferable. In addition, when the content of the compound exceeds about 20% by weight, the viscosity of the photoresist composition becomes too high to form a photoresist film having a uniform thickness, which is not preferable. Therefore, the photoresist composition of the present invention preferably contains about 8 to about 20% by weight, more preferably about 9 to about 15% by weight of the compound represented by Formula 1 or 2.

The photoresist composition of the present invention comprises a photosensitizer. The photosensitizer is a photoacid generator that reacts to light to produce an acid, ie hydrogen ions (H ⁺ ). The acid generated by the photosensitizer leaves the end group, that is, the functional group represented by R ₅ , R ₆ and R ₇ , from the compound represented by Formula 1 or 2 above. The functional groups represented by R ₅ , R ₆ and R ₇ are easily separated from the compound by reaction with an acid as an acid-decomposable functional group. As a result, the solubility of the compound in the developer is changed.

When the photoresist composition of the present invention contains less than about 0.1% by weight of the photosensitizer, the acid-decomposable functional group is not sufficiently released from the compound represented by Formula 1 or 2 due to the lack of the amount of acid generated by exposure. It is difficult to form a vivid photoresist pattern, which is not preferable. In addition, when the content of the photosensitizer exceeds about 0.5% by weight, it is not preferable because an excessive amount of acid is generated, so that the edge of the pattern may be rounded in the developing process or the photoresist film may be lost. Therefore, the photoresist composition of the present invention preferably contains about 0.1 to about 0.5% by weight of the photosensitizer, and more preferably about 0.15 to about 0.4% by weight.

Examples of the photosensitizer which can be used in the photoresist composition of the present invention include sulfonium salt, triarylsulfonium salt, iodonium salt, diaryliodonium salt, nitrobenzyl ester ( nitrobenzyl ester, disulfone, diazo-disulfone, sulfonate, trichloromethyl triazine, N-hydroxysuccinimide triflate (N-hydroxysuccinimide triflate). These can be used individually or in mixture.

More specific examples of the photosensitizer include triphenylsulfonium triflate, triphenylsulfonium antimony salt, diphenyliodonium triflate, and diphenyliodonium antimonate. antimony salt), methoxydiphenyliodonium triflate, di-tert-butyldiphenyliodonium triflate, 2,6-dinitrobenzyl sulfonate (2,6- dinitrobenzyl sulfonate, pyrogallol tris (alkylsufonate), norbornene-dicarboxyimide triflate, triphenylsulfonium nonalate, diphenylyodonium Nona plate (diphenyliodonium nonaflate), methoxydiphenyliodonium nonaflate, di-t-butyldiphenyl iodonium noa Di-tert-butyldiphenyliodonium nonaflate, N-hydroxysuccinimide nonaflate, norbornene dicarboxyimide nonaflate, triphenylsulfonium perfluorooctanesulfonate (N-hydroxysuccinimide nonaflate) triphenylsulfonium perfluorooctanesulfonate, diphenyliodonium perfluorooctanesulfonate, methoxyphenyliodonium perfluorooctanesulfonate, di-tert-butyldiphenyliodonium triflate), N-hydroxysuccinimide perfluorooctanesulfonate, norbornene dicarboxyimide perfluorooctanesulfonate, and the like. These can be used individually or in mixture.

Examples of organic solvents that can be used in the photoresist composition of the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol methyl ether, Methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol methyl ether Propylene glycol methyl ether acetate, propylene glycol propyl ether acetate, diethylene glycol dimethyl ether, ethyl lactate, toluene, xylene xylene, methyl ethyl keto ne), cyclohexanone, 2-heptanone, 3-heptanone, 3-heptanone, 4-heptanone, and the like. These can be used individually or in mixture.

The photoresist composition according to the embodiment of the present invention may further include an organic base. The organic base controls the diffusion distance of the acid generated by the photosensitive agent to form a clear photoresist pattern and contributes to reducing the roughness of the line width.

In the photoresist composition according to an embodiment of the present invention, if the content of the organic base is less than about 0.1% by weight, it is not preferable because there is little influence on the sharpness of the photoresist pattern and the roughness of the line width. In addition, when the content of the organic base exceeds about 5% by weight, the line width of the photoresist pattern is no longer reduced, which is economically undesirable. Therefore, the photoresist composition according to one embodiment of the present invention preferably contains about 0.1 to about 5 wt% of the organic base, and more preferably about 1 to about 4 wt%.

Specific examples of the organic base that can be used in the photoresist composition according to an embodiment of the present invention include triethylamine, triisobutylamine, triisooctylamine, and triisodecylamine ), Diethanolamine, triethanolamine, and the like. These can be used individually or in mixture.

The photoresist composition according to the present invention may include a nonlinear low molecular weight compound instead of a polymer to implement a fine pattern having a molecular resolution. In addition, when applied to form a photoresist pattern, the solubility in the developer is constant, there is no tangling phenomenon of the chain can reduce the line width roughness (LWR).

Hereinafter, a method of forming a photoresist pattern according to exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Formation method of photoresist pattern

3 to 5 are cross-sectional views illustrating a method of forming a photoresist pattern according to an embodiment of the present invention.

Referring to Figure 3, first prepare an object. Examples of the object include a substrate such as a silicon wafer or a substrate including a predetermined structure or film. For example, the object may be a substrate on which a silicon nitride film is formed. Hereinafter, the case where the substrate 100 is used as the object will be described. In this case, a cleaning process for removing moisture or contaminants present on the surface of the substrate 100 may be selectively performed.

Subsequently, the photoresist film 200 is formed by applying a photoresist composition including a compound represented by the following Formula 1 or 2, a photosensitive agent, and an organic solvent onto the substrate 100.

...... (1)

...... (One)

...... (2)

...... (2)

In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, and X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group. In addition, in said Formula 2, R <_8> represents the residue from which the hydrogen atom of the carboxy group was removed from the tricarboxylic acid compound. The photoresist composition is as described above, and further detailed description thereof will be omitted.

The first baking process may be performed by heating the substrate 100 on which the photoresist film 200 is formed. The first baking process is carried out at a temperature of about 90 ℃ to about 130 ℃. As the first baking process is performed, adhesion between the substrate 100 and the photoresist film 200 is increased.

Referring to FIG. 4, the substrate 100 is exposed. Specifically, the mask 300 having a predetermined pattern is positioned on the mask stage of the exposure apparatus, and then the mask 300 is aligned on the substrate 100 on which the photoresist film 200 is formed. Subsequently, light is irradiated for a predetermined time so that the photoresist film 200 formed on the substrate 100 selectively reacts with light partially passing through the mask 300. Examples of the light that can be used in the exposure process are mercury-xenon (Hg-Xe) light, G-line ray, I-line ray, krypton fluoride laser ), Argon fluoride laser, electron beam, X-ray, etc. are mentioned. Accordingly, the light irradiated portion 210 of the photoresist film 200 has a different solubility from the light irradiated portion 210.

A second baking process may be performed on the photoresist film 200 on which the exposure process is performed. The second baking process may be performed at a temperature of about 90 ° C to about 160 ° C. As the second baking process is performed, the portion 210 irradiated with light of the photoresist film 200 may be easily dissolved in a specific solvent.

Referring to FIG. 5, the photoresist pattern 220 is formed by removing the portion 210 to which the light of the photoresist film 200 is irradiated using a developer. Specifically, it may be developed using a developer such as tetramethylammonium hydroxide (TMAH).

Subsequently, the photoresist pattern 220 is completed through a conventional process such as cleaning. The structures formed under the photoresist pattern may be etched using the formed photoresist pattern 220 as a mask to form various structures of the semiconductor device.

As described above with reference to FIGS. 1 and 2, a photoresist composition including a conventional polymer has a large size of molecules due to the nature of the polymer, making it difficult to form a fine pattern having a resolution at a molecular level. It is very rough and the thickness is not constant. In addition, depending on the molecular weight of the polymer, the solubility in the developer is not constant and chain entanglement occurs, which further increases the line width roughness (LWR) during the development process. In contrast, the photoresist composition of the present invention contains a low-molecular compound instead of a polymer, so that the building blocks forming the photoresist pattern are relatively small.

6 and 7 are schematic diagrams for explaining the photoresist pattern formed using the photoresist composition according to the present invention.

6 and 7, the photoresist composition according to the present invention includes a non-linear low molecular compound instead of the conventional polymer, and thus the size of the building block forming the photoresist pattern is small. Therefore, it is possible to form a photoresist pattern having a high resolution of the molecular level. In addition, since it contains a compound having a single molecular weight, the solubility in the developer is constant, and the entanglement between the molecules is negligible compared to the polymer, thereby greatly reducing the line width roughness (LWR) of the photoresist pattern. You can. Therefore, using the photoresist composition of the present invention can form a high-resolution fine pattern, it is possible to reduce the roughness of the line width.

Hereinafter, the compound for photoresists and the photoresist composition comprising the same according to the present invention will be described in more detail through Synthesis Examples and Examples.

Synthesis of Compound for Photoresist

Synthesis Example 1

Dissolve about 5.0 g of glycerol, about 18.5 g of glutaric anhydride, and traces of pyridine used as catalyst in about 150 mL of 1,4-dioxane. And reacted by reflux for about 24 hours. 1,4-dioxane and pyridine were evaporated to give the first product. The first product was dissolved in an excess of thionyl chloride and stirred at room temperature for about 2 hours to react, and then thionyl chloride was evaporated to obtain a second product. In a nitrogen atmosphere, about 2.2 g of triethylamine and about 10.0 g of tert-butyl cholate were dissolved in about 200 mL of anhydrous diethyl ether, and the second dissolved in anhydrous diethyl ether. About 15 g of the product was slowly dropped and reacted. Triethylamine salt was removed using a filter and the final product was separated using column chromatography.

In order to confirm the structure of the final product, hydrogen-nuclear magnetic resonance ( ¹ H-Nuclear Magnetic Resonance, ¹ H-NMR) spectrum and Fourier Transform-Infrared (FT-IR) spectrum were measured. ¹ H-NMR spectra were measured by dissolving the final product in chloroform-d (CDCl ₃ ). ¹ H-NMR spectra have chemical shifts (δ) of 0.65 ppm (3H, s, 18methyl), 0.88 ppm (3H, s, 19methyl), 0.96 ppm (3H, d, J = 6 Hz, 21methyl), 1.01 -2.02 ppm (26H, m), 1.41 ppm (9H, s, t-butyl), 3.86 pm (1H, m) and 3.96 (1H, m). FT-IR spectra were found to be 3444 cm ⁻¹ (OH), 2938 cm ⁻¹ (aliphatic and cycloaliphatic CH) and 1730 cm ⁻¹ (C═O of the ester group). ^As a result of analyzing the ¹ H-NMR spectrum and the FT-IR spectrum, it was confirmed that the final product was a compound represented by the following formula (11).

...... (11)

...... (11)

Synthesis Example 2

About 4.8 g of 1,3,5-cyclohexanetricarboxylic acid was added to an excess of thionyl chloride, and the mixture was stirred at room temperature for about 2 hours, and then dissolved. The reaction was performed at reflux for about 2 hours. Thionyl chloride was evaporated and washed three times with dry toluene to obtain 1,3,5-cyclohexanetricarbonyl chloride (1,3,5-cyclohexanectricarbonyl chloride). In a nitrogen atmosphere, about 2.2 g of triethylamine and about 10.0 g of tert-butyl cholate were dissolved in about 200 mL of anhydrous diethyl ether, and then dissolved in 1,3 anhydrous diethyl ether. The reaction was slowly dropped with about 15.5 g of, 5-cyclohexanetricarbonyl chloride. After reacting for about 6 hours at room temperature, the triethylamine salt was removed using a filter, and the final product was separated by column chromatography.

In order to confirm the structure of the final product, hydrogen-nuclear magnetic resonance ( ¹ H-Nuclear Magnetic Resonance, ¹ H-NMR) spectrum and Fourier Transform-Infrared (FT-IR) spectrum were measured. ¹ H-NMR spectra were measured by dissolving the final product in chloroform-d (CDCl ₃ ). ¹ H-NMR spectra have chemical shifts (δ) of 0.65 ppm (3H, s, 18methyl), 0.88 ppm (3H, s, 19methyl), 0.96 ppm (3H, d, J = 6 Hz, 21methyl), 1.01 -2.02 ppm (26H, m), 1.41 ppm (9H, s, t-butyl), 3.86 pm (1H, m) and 3.96 (1H, m). FT-IR spectra were found to be 2940 cm ⁻¹ (alicyclic CH) and 1738 cm ⁻¹ (C═O of the ester group). ^As a result of analyzing the ¹ H-NMR spectrum and the FT-IR spectrum, it was confirmed that the final product was a compound represented by the following formula (12).

...... (12)

...... (12)

Photoresist Composition Preparation

<Example 1>

About 11.1% by weight of the compound represented by Formula 11 synthesized in Synthesis Example 1, about 0.2% by weight of triphenylsulfonium triflate, and about 88.7% by weight of propylene glycol methyl ether acetate were mixed to prepare a photoresist composition.

<Example 2>

About 11% by weight of the compound represented by Formula 12 synthesized in Synthesis Example 2, about 0.2% by weight of triphenylsulfonium triflate and about 88.8% by weight of propylene glycol methyl ether acetate were prepared to prepare a photoresist composition.

Evaluation of Formation of Photoresist Pattern

The formation of the photoresist pattern was evaluated for the photoresist composition prepared in Example.

First, a photoresist film was formed by spin coating the photoresist composition prepared in Example 1 on a silicon wafer. The silicon substrate on which the photoresist film was formed was first baked at about 110 ° C. for about 60 seconds. The photoresist film was exposed using a mask on which a predetermined pattern was formed. The exposure process was performed by irradiating about 12 mJ / cm ² using a mercury-xenon (Hg-Xe) lamp. The exposed photoresist film was second baked at about 110 ° C. for about 60 seconds. The photoresist film was developed by contacting about 2.38% of tetramethylammonium hydroxide (TMAH) for about 60 seconds. Subsequently, a cleaning process and a drying process for removing residual developer were performed to complete the photoresist pattern. Whether the photoresist pattern was formed was confirmed using an electron microscope.

8 is an electron micrograph showing a photoresist pattern formed using the photoresist composition prepared in Example.

As shown in FIG. 8, when the photoresist pattern formed using the photoresist composition prepared in Example 1 was observed with an electron microscope, it was confirmed that the photoresist pattern having a predetermined thickness was clearly formed. The portions that were exposed and removed by the developer and the portions that were not exposed and remained in the photoresist pattern were clearly distinguished. Therefore, it was confirmed that the photoresist composition of the present invention can form a photoresist pattern even though it contains a nonlinear low molecular compound that is not a conventional polymer. On the other hand, even when the photoresist pattern was formed using the photoresist composition prepared in Example 2, it was found that the photoresist pattern was clearly formed as in the case of Example 1.

As described above, the photoresist composition according to the present invention includes a non-linear low molecular compound instead of the conventional polymer to form a photoresist pattern having a high resolution at the molecular level. In addition, the photoresist composition according to the present invention contains a compound having a single molecular weight so that the solubility in the developer is constant and there is no entanglement between the molecules. Therefore, when the photoresist pattern is formed, line width roughness (LWR) may be greatly reduced. As a result, the photoresist composition of the present invention can form a fine pattern of high resolution and can greatly reduce the roughness of the line width.

As described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art without departing from the spirit and scope of the present invention described in the claims below It will be appreciated that various modifications and variations can be made in the present invention.

Claims (17)

Compound for photoresist represented by the following formula (1) or (2).

...... (One)

...... (2) (In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group, R ₈ represents a carboxyl group in a tricarboxylic acid compound Represents a residue from which the hydrogen atom of The compound for photoresist according to claim 1, wherein in Formula 1, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from glycerol or cyclohexanetriol. According to claim 1, wherein in Formula 1 R ₂ , R ₃ And R _{4 It} is independently glutaric acid (glutaric acid), succinic acid (succinic acid) or 3,3-tetramethylene glutaric acid (3,3-tetramethyleneglutaric acid) represents a residue from which a hydrogen atom of a carboxyl group has been removed. The photoresist of claim 1, wherein R ₈ in Formula 2 represents a residue from which a hydrogen atom of a carboxyl group is removed from 1,3,5-cyclohexanetricarboxylic acid (1,3,5-cyclohexanetricarboxylic acid). compound. The compound for photoresist according to claim 1, wherein the compound is represented by the following Formulas 3 to 9.

...... (3)

...... (4)

...... (5)

(6)

(7)

...... (8)

(9) (In Formulas 3 to 9, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, and X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group. Indicates) A compound represented by the following Formula 1 or 2;

...... (One)

...... (2) (In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydropyranyl group or 1-ethoxyethyl group, X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group, R ₈ represents a carboxyl group in a tricarboxylic acid compound Represents a residue from which the hydrogen atom of Photosensitizers; And Photoresist composition comprising an organic solvent. The method according to claim 6, wherein the total weight of the photoresist composition, comprising 8 to 20% by weight of the compound represented by the formula 1 or 2, 0.1 to 0.5% by weight of the photosensitizer and an extra organic solvent Photoresist composition. The photosensitive agent of claim 6, wherein the photosensitive agent is a sulfonium salt, a triarylsulfonium salt, an iodonium salt, a diaryliodonium salt, a nitrobenzyl ester, a dilobenzyl ester Group consisting of sulfone, diazo-disulfone, sulfonate, trichloromethyl triazine and N-hydroxysuccinimide triflate Photoresist composition comprising at least one selected from. The method of claim 6, wherein the organic solvent is ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol methyl ether, methyl cellosolve acetate ( methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol methyl ether acetate ether acetate, propylene glycol propyl ether acetate, diethylene glycol dimethyl ether, ethyl lactate, toluene, xylene, methyl ethyl Ketone (methyl ethyl ketone), cyclohexanone, 2-hep A photoresist composition comprising at least one selected from the group consisting of 2-heptanone, 3-heptanone, 3-heptanone, and 4-heptanone. 7. The photoresist composition of claim 6, further comprising an organic base. The method of claim 10, wherein the total weight of the photoresist composition, 8 to 20% by weight of the compound represented by the formula 1 or 2, 0.1 to 0.5% by weight of the photosensitizer, 0.1 to 5% by weight of the organic base and extra A photoresist composition comprising an organic solvent. 11. The method of claim 10, wherein the organic base comprises at least one selected from the group consisting of triethylamine, triisobutylamine, triisooctylamine, triisodecylamine, diethanolamine and triethanolamine Resist composition. Forming a photoresist film by applying a photoresist composition comprising a compound, a photosensitizer, and an organic solvent represented by the following Formula 1 or 2 on the object;

...... (One)

...... (2) (In Formulas 1 and 2, R ₁ represents a residue from which a hydrogen atom of a hydroxyl group is removed from a triol compound, R ₂ , R ₃ and R ₄ represent a residue from which a hydrogen atom of a carboxyl group is removed from a dicarboxylic acid compound, R ₅ , R ₆ and R ₇ independently represent a t-butyl group, tetrahydro pyranyl group or 1-ethoxyethyl group, X ₁ to X ₆ independently represent a hydrogen atom or a hydroxyl group, R ₈ represents a carboxyl group in a tricarboxylic acid compound Represents a residue from which the hydrogen atom of Exposing the photoresist film; And And partially removing the photoresist film to form a photoresist pattern. The method of claim 13, wherein the photoresist composition comprises 8 to 20 wt% of the compound represented by Formula 1, 0.1 to 0.5 wt% of the photosensitive agent, and an extra organic solvent. The method of claim 13, wherein exposing the photoresist film comprises mercury-xenon (Hg-Xe) light, G-line ray, I-line ray, krypton fluoride laser. (krypton fluoride laser), argon fluoride laser (argon fluoride laser), an electron beam (electron beam) or X-ray (X-ray), characterized in that the method of forming a photoresist pattern. The method of claim 13, further comprising first baking the photoresist film at a temperature of 90 ° C. to 130 ° C. before exposing the photoresist film. The method of claim 13, further comprising, after exposing the photoresist film, second baking the photoresist film at a temperature between 90 ° C. and 160 ° C. 15.

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