KR20010016642A - Organic polymer for preventing diffused reflection and process for producing the same - Google Patents

Abstract

PURPOSE: Provided is an organic polymer for preventing diffused reflection, which can be used as an antireflection film in a hyperfine pattern forming process using 193 nm ArF and 248 nm KrF light in a semiconductor process. CONSTITUTION: The organic polymer for preventing diffused reflection is represented by the formula 1, which has an average molecular weight of 500-100000 and is produced by polymerizing a poly(hydroxy phenyl-formaldehyde) resin and epichlorohydrin in the equivalent ratio of 1:1 in a solvent such as tetrahydrofuran, toluene, benzene, methyl ethyl ketone, or dioxane. In the formula, R1 is hydrogen, substituted or unsubstituted C1-C4 alkyl, and n is an average degree of polymerization.

Description

Organic diffuse reflection prevention polymer and manufacturing method thereof

The present invention prevents the reflection of the underlying layer in the ultrafine pattern formation process using the photoresist for 248 nm KrF and 193 nm ArF lithography during the semiconductor device manufacturing process and removes the sine wave in the thickness change of ArF light and photoresist itself. The present invention relates to an organic anti-reflective polymer which can be used in forming ultrafine patterns of 64M, 256M, 1G, and 4G DRAM as an antireflection organic material, and a method of manufacturing the same. The present invention also relates to an antireflective composition containing such an organic antireflective polymer, an antireflection film using the same, and a method of manufacturing the same.

In the ultra-fine pattern formation process of the semiconductor manufacturing process, a reflective dimension of the sine wave due to the optical properties of the lower layer on the wafer and a change in the thickness of the photoresist layer, and a CD (critical dimension) by diffracted and reflected light from the lower layer ) Inevitably occurs. Therefore, the introduction of an organic material that absorbs light well in the wavelength range of light used as an exposure source has been proposed to introduce a film layer that can prevent reflection in the lower film layer, which is called an anti-reflection film.

The antireflection film is classified into an inorganic antireflection film and an organic antireflection film according to the type of material used largely, or is classified into an absorption antireflection film and an interferometer antireflection film according to a mechanism. In the micropattern forming process using an I-line of 365 nm wavelength, an inorganic antireflection film is mainly used. TiN and amorphous carbon (Amorphous C) are used as an absorption system, and SiON is mainly used as an interferometer.

In the ultrafine pattern formation process using KrF light, SiON has been mainly used as an inorganic type, and in recent years, efforts to use organic compounds in antireflection films have been continued. In light of the trends to date, most of the existing organic anti-reflective coatings for KrF must satisfy the following basic conditions.

First, there should be no phenomenon that the photoresist is dissolved and peeled off by the solvent when the process is applied. To this end, the molded film must be designed to achieve a crosslinked structure, and chemicals should not be generated as a by-product.

Second, there should be no entry of chemicals such as acids or amines from the antireflection film. If the acid is migrated from the anti-reflection film, undercutting occurs at the bottom of the pattern, and bases such as amines tend to cause footing phenomenon.

Third, the anti-reflection film should have a relatively high etching rate compared to the upper photoresist so that a smooth etching process can be performed using the photoresist as a mask during etching.

Fourth, therefore, the antireflection film should be able to serve as a sufficient antireflection film with a thickness as thin as possible.

On the other hand, in the ultrafine pattern formation process using ArF light, such an anti-reflection film has not been developed yet. In addition, in the case of the inorganic antireflection film, a material for controlling the interference at 193 nm, which is a light source, has not been published yet, and the recent trend is to study the use of organic compounds in the antireflection film.

Therefore, in all photoresist films, it is necessary to use an organic anti-reflective material having a high absorption at a specific wavelength in order to prevent sine waves and reflections generated during exposure and to remove the influence of back diffraction and reflected light from the lower layer. This is an urgent task.

Accordingly, the present invention has been made in an effort to provide a novel compound that can be used as an antireflection film in an ultrafine pattern formation process using 193 nm ArF and 248 nm KrK light during a semiconductor manufacturing process.

Still another object of the present invention is to provide a method for preparing a compound which can prevent diffuse reflection.

Still another object of the present invention is to provide an anti-reflective composition containing the compound for preventing anti-reflection and a manufacturing method thereof.

Still another object of the present invention is to provide an antireflection film formed using such an antireflection composition and a method of forming the same.

In order to achieve the above technical problem, the present invention provides a polymer of Formula 1 below.

In the above formula,

R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl,

n represents the average degree of polymerization.

It is preferable that the polymer of Formula 1 according to the present invention has an average molecular weight (Mn) of 500 to 100,000.

The polymer of Formula 1 according to the present invention is designed such that absorption occurs at 248 nm by using a novolak having a high absorbance at 193 nm as the main chain of the resin and introducing a chromophore so that absorption occurs at 193 nm and 248 nm.

The polymer of Chemical Formula 1 according to the present invention may be prepared by reacting poly (hydroxyphenyl-formaldehyde) resin (I) and epichlorohydrin (II) in a solvent as in Scheme 1 below.

In the above formula,

R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl,

n represents the average degree of polymerization.

At this time, it is preferable that the amount of each reactant (I) and (II) used in Scheme 1 is about 1: 1 equivalent ratio.

As a solvent used in the method for preparing a polymer of Chemical Formula 1 according to the present invention, a general organic solvent may be used, and preferably selected from the group consisting of tetrahydroxyfuran, toluene, benzene, methyl ethyl ketone or dioxane. Can be used.

The present invention is also characterized in that it provides an antireflection film composition comprising one or two or more compounds selected from the group consisting of the polymer of Formula 1 and the anthracene derivatives listed in Table 1 below.

In Table 1 above

R ₂ , R ₃ , or R ₄ each independently represent hydrogen, substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of C ₁ to C ₅ , and p represents an integer.

The method for preparing an antireflective coating composition according to the present invention is prepared by dissolving the polymer of Chemical Formula 1 in an organic solvent and then adding 0.1 to 30% by weight of one or more compounds selected from the group consisting of anthracene derivatives of Table 1 above. .

The organic solvent which can be used at this time can use a conventional organic solvent, Preferably it consists of ethyl 3-ethoxy propionate, methyl 3-methoxy propionate, cyclohexanone, and propylene glycol methyl ether acetate. You can use the selected one from the group.

In addition, the amount of solvent used in the production of the antireflection film composition of the present invention is preferably used 200 to 5000% by weight per weight of the polymer of the formula (1).

The present invention provides an anti-reflection film composed of one or two or more compounds selected from the group consisting of the polymer of Formula 1 alone or of the polymer of Formula 1 and the anthracene derivatives of Table 1 above.

The antireflection film according to the present invention is a predetermined process after filtering the composition containing one or two or more compounds selected from the group consisting of the polymer of Formula 1 alone or the polymer of Formula 1 and the anthracene derivative of Table 1 After coating on the rough wafer and hard-baked for 10 to 1000 seconds at 100 ~ 300 ℃ can be prepared by crosslinking the anti-reflection film resin.

The anti-reflective coating composition comprising the polymer of Formula 1 or the same according to the present invention is coated on a wafer and then hardbaked at a high temperature so that a reaction occurs between the epoxy groups in the polymer of Formula 1 to form a crosslinked structure, thereby forming moldability, Confidentiality and clarity

The polymer of Chemical Formula 1 according to the present invention was found to exhibit excellent performance as an organic anti-reflective coating of the ultra-fine pattern forming process using 248nm KrF and 193 ArF laser as a light source, E-beam, EUV as an exposure light source in addition to ArF light (extremely ultraviolet), an ion beam, etc., it was confirmed that the excellent anti-reflective effect.

Hereinafter, the present invention will be described in more detail. In addition, the present embodiment is not intended to limit the scope of the present invention but is presented by way of example only.

Example 1 Synthesis of Poly (glycidylphenylether-formaldehyde) Polymer

28.6 g (0.5 equiv) of poly (hydroxyphenyl-formaldehyde) resin (Mw = 3000) is completely dissolved in 200 g of tetrahydrofuran (THF) prepared in a 500 ml round bottom flask. Add 4 g (0.5 equiv) of pyridine and mix thoroughly. At this time, an exothermic reaction takes place while the reactor is cooled. Then, 4.6 g (0.5 equivalent) of epichlorohydrin prepared in advance is slowly added dropwise at room temperature and reacted for about 20 hours. Upon completion of the reaction, the solution was neutralized with aqueous 0.1 N sulfuric acid solution, precipitated in ethyl ether solvent, filtered and dried to obtain a poly (glycidylphenyl ether-formaldehyde) polymer of formula 2 according to the present invention (yield 86 %).

Example 2 Synthesis of Poly (Orso-Cresylglycidylphenylether-formaldehyde) Polymer

31.4 g (0.5 equiv) of poly (ortho-cresylhydroxyphenyl-formaldehyde) resin (Mw = 3000) is completely dissolved in 200 g of tetrahydrofuran (THF) prepared in 500 ml round bottom flask. Add 4 g (0.5 equiv) of pyridine and mix thoroughly. At this time, an exothermic reaction takes place while the reactor is cooled. Then, 4.6 g (0.5 equivalent) of epichlorohydrin prepared in advance is slowly added dropwise at room temperature and reacted for about 20 hours. Upon completion of the reaction, the solution was neutralized with aqueous 0.1 N sulfuric acid solution, precipitated in a normal nucleic acid solvent, filtered and dried to obtain a poly (ortho-cresylglycidylphenylether-formaldehyde) polymer of formula 3 according to the present invention. (Yield 91%).

Example 3 Preparation of Poly (Glycidylphenylether-Formaldehyde) / Anthrone-type Antireflection Film

After dissolving 50 mg of the polymer of Chemical Formula 2 according to the present invention prepared in Example 1 in about 100 g of propylene glycol methyl ether acetate (PGMEA), 10 mg of anthrone in Table 1 was completely dissolved, and then filtered solution. It is applied to a wafer and hardbaked at 250 ° C. for 100 seconds to prepare a poly (glycidylphenyl ether-formaldehyde) / anthrone-based antireflection film according to the present invention.

Example 4 Preparation of Poly (glycidylphenylether-formaldehyde) / 9-tert-butylanthracene-based antireflection film

After dissolving 50 mg of the polymer of Formula 2 according to the present invention prepared in Example 1 in about 100 g of propylene glycol methyl ether acetate (PGMEA), in Table 1, R _2, R _3, R ₄ is substituted with a methyl group 9 After dissolving completely by adding 7.5 mg of -tert-butylanthracene, the filtered solution was applied to a wafer and subjected to a hard bake at 275 ° C. for 90 seconds to give a poly (glycidylphenyl ether-formaldehyde) / 9-. A tert-butyl anthracene type antireflection film is prepared.

Example 5 Preparation of Poly (Orso-Cresylglycidylphenylether-Formaldehyde) / Anthraclavic Acid Antireflection Film

After dissolving 50 mg of the polymer of Chemical Formula 3 according to the present invention prepared in Example 2 in about 100 g of propylene glycol methyl ether acetate (PGMEA), 5 mg of antraflavic acid in Table 1 was completely dissolved, and then filtered solution. Was applied to a wafer and hardbaked at 225 ° C. for 120 seconds to prepare a poly (ortho-cresylglycidylphenylether-formaldehyde) / anthraflavic acid antireflection film according to the present invention.

Example 6 Preparation of Poly (Orso-Cresylglycidylphenylether-Formaldehyde) / 1-Anthracenecarboxylic Acid Antireflection Film

After dissolving 50 mg of the polymer of Formula 3 according to the present invention prepared in Example 2 in about 100 g of propylene glycol methyl ether acetate (PGMEA), in Table 1, 7.5 mg of 1-anthracenecarboxylic acid, wherein R ₁ is a hydrogen group, was added. After dissolving completely, the filtered solution was applied to a wafer and subjected to a hard bake at 275 ° C. for 100 seconds to obtain a poly (ortho-cresylglycidylphenylether-formaldehyde) / 1-anthracenecarboxylic acid system according to the present invention. An antireflection film is prepared.

As described above, when the polymer of Chemical Formula 1 according to the present invention is used as a reflective ring film in an ultrafine pattern forming process in a semiconductor manufacturing process, 64M, 256M, 1G, 4G, The stable ultrafine pattern of 16G DRAM can be formed, increasing the yield of products.

In addition, the novolak-based resins used in the present invention have an advantage that the production cost can be reduced at a considerably low cost.

Claims (13)

A polymer used as an organic antireflection film of the formula (1). (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. The polymer according to claim 1, wherein the polymer has an average molecular weight of 500 to 100,000. A method of preparing a polymer used in the antireflection film of Chemical Formula 1 by reacting poly (hydroxyphenyl-formaldehyde) resin (I) and epichlorohydrin (II) in a solvent as in Scheme 1 below. (Scheme 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. 4. A process according to claim 3, wherein the amount of each reactant (I) and (II) is used in a ratio of about 1: 1 equivalents. The method of claim 3, wherein the solvent is selected from the group consisting of tetrahydroxyfuran, toluene, benzene, methylethylketone or dioxane. A polymer of the following formula (1) and anthracene, 9-anthracenemethanol, 9-anthracenecarbonitrile, 9-anthracenecarboxylic acid, ditranol, 1,2,10-anthracentriol, anthralflavic acid, 9-anthralaldehyde Oxime, 9-anthralaldehyde, 2-amino-7-methyl-5-oxo-5H- [1] benzopyrano [2,3-b] pyridine-3-carbonitrile, 1-aminoanthraquinone, anthraquinone 2-carboxylic acid, 1,5-dihydroxy, anthraquinone, anthrone, 9-anthryltrifluoromethyl ketone, 9-alkyl anthracene derivative of formula 4, 9-carboxy anthracene of formula 5 An anti-reflective coating composition comprising one or two or more compounds selected from the group consisting of an anthracene derivative composed of a derivative and a 1-carboxyl anthracene derivative of formula (6). (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. In the above formula R ₂ , R ₃ , or R ₄ each independently represent hydrogen, substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of C ₁ to C ₅ , and p represents an integer. After dissolving the polymer of Formula 1 in an organic solvent of 200 to 5000% by weight per polymer weight, anthracene, 9-anthracenemethanol, 9-anthracenecarbonitrile, 9-anthracenecarboxylic acid, dithranol, 1,2, 10-anthracentriol, anthraclavic acid, 9-anthralaldehyde oxime, 9-anthralaldehyde, 2-amino-7-methyl-5-oxo-5H- [1] benzopyrano [2,3-b] Pyridine-3-carbonitrile, 1-aminoanthraquinone, anthraquinone-2-carboxylic acid, 1,5-dihydroxy, anthraquinone, anthrone, 9-anthryltrifluoromethyl ketone, of formula (4) An anti-reflective coating composition comprising the addition of one or two or more compounds selected from the group consisting of a 9-alkyl anthracene derivative, a 9-carboxyl anthracene derivative of Formula 5 and a 1-carboxyl anthracene derivative of Formula 6 Manufacturing method. (Formula 4) (Formula 5) (Formula 6) In the above formula R ₂ , R ₃ , or R ₄ each independently represent hydrogen, substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of C ₁ to C ₅ , and p represents an integer. The method of claim 7, wherein the amount of the additive is 0.1 to 30% by weight. 8. The method of claim 7, wherein the organic solvent is selected from the group consisting of ethyl 3-ethoxypropionate, methyl 3-methoxy propionate, cyclohexanone, and propylene glycol methyl ether acetate. . An anti-reflection film containing a polymer of the formula (1). (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. Applying a solution obtained by dissolving a polymer of Formula 1 in a solvent to a wafer which has been subjected to a predetermined process; And hard-baking the wafer at 100-300 ° C. for 10-1000 seconds. (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. A polymer of the following formula (1) and anthracene, 9-anthracenemethanol, 9-anthracenecarbonitrile, 9-anthracenecarboxylic acid, ditranol, 1,2,10-anthracentriol, anthralflavic acid, 9-anthralaldehyde Oxime, 9-anthralaldehyde, 2-amino-7-methyl-5-oxo-5H- [1] benzopyrano [2,3-b] pyridine-3-carbonitrile, 1-aminoanthraquinone, anthraquinone 2-carboxylic acid, 1,5-dihydroxy, anthraquinone, anthrone, 9-anthryltrifluoromethyl ketone, 9-alkyl anthracene derivative of formula 4, 9-carboxy anthracene of formula 5 Filtering a composition consisting of one or more compounds selected from the group consisting of derivatives and 1-carboxyl anthracene derivatives of Formula 6; Coating the composition on a wafer and hard-baking at 100-300 ° C. for 10-1000 seconds. (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization. (Formula 4) (Formula 5) (Formula 6) In the above formula R ₂ , R ₃ , or R ₄ each independently represent hydrogen, substituted or unsubstituted straight or branched chain alkyl, cycloalkyl, alkoxyalkyl or cycloalkoxyalkyl of C ₁ to C ₅ , and p represents an integer. A semiconductor device comprising a anti-reflection film containing a polymer of the general formula (1). (Formula 1) In the above formula, R ₁ represents hydrogen, substituted or unsubstituted C ₁ to C ₄ alkyl, n represents the average degree of polymerization.