KR20170114476A - Separation - meterial Composition for resist and manufacturing methods - Google Patents

Abstract

The present invention relates to a remover composition of a photoresist or a residue thereof (hereinafter, simply referred to as "resist" in some cases) in a photolithography process, and a resist stripping method using the composition. More particularly, the present invention relates to a resist stripper composition which enables stripping of a resist in a photolithography process of a semiconductor field and enables stripping of the resist without adversely affecting the silicon oxide film or the like underlying the resist, And a method for peeling a resist.

Description

[0002] Separation-meterial Composition for resist and manufacturing methods [

None

Photoresists have been used for photolithography processes for forming fine patterns in semiconductor manufacturing processes such as integrated circuits and transistors. For example, in the case of forming a silicon oxide film in a desired pattern on a silicon substrate, the substrate is processed in the following process, for example. That is, first a silicon oxide film is formed on the surface of the silicon substrate for the first time, a photoresist is applied to the silicon oxide film, and then a resist film is formed. Then, a desired pattern is obtained by exposure and development using a photomask corresponding to the desired pattern. Further, an unnecessary oxide film is removed by an etching process such as plasma doping, using the pattern as a mask, on the substrate from which a desired pattern is obtained. Finally, by removing the resist and cleaning the surface of the substrate, a silicon oxide film having a desired pattern can be obtained. Examples of the method for removing the unnecessary resist after the etching process include a dry painting method such as oxygen plasma ashing (for example, Patent Document 1, etc.) and a method of immersing into a peeling agent containing various additives Two types of wet type are known. Oxygen plasma ashing, which is an example of a dry painting method, is a method of decomposing, painting, and removing a resist by a reaction between an oxygen gas plasma and a resist, and is called a non-pollution method. However, when the resist is removed by ashing, There is a problem that the surface of the substrate tends to be damaged, and there is a problem that particles adhere to and remain on the surface of the substrate. In addition, there is also a problem that an expensive facility for generating plasma is generally required. On the other hand, as a wet process, for example, there is known a method of inorganicizing (removing) a resist by the strong oxidizing power of peroxy sulfuric acid (carnoic acid) obtained by the reaction of thermally concentrated sulfuric acid with hydrogen peroxide as an inorganic release solvent For example, Patent Document 2). However, this method has a problem in that the use of high-temperature concentrated sulfuric acid has a high risk. In addition, since a molten acid having a strong oxidizing power generates an unnecessary oxide on the metal surface or melts the metal, There is a problem that it can not be applied to a substrate having wiring.

In such a situation, the resist peeling can be performed by a simple and effective method which does not cause the problems of the above-mentioned dry painting method and does not cause problems such as dissolving the metal wiring of the inorganic type removing solvent typified by the wet type A method is required, and there is a demand for the existence of a drug solution that meets this need.

Japanese Patent Application Laid-Open No. 5-291129 Japanese Patent Application Laid-Open No. 3-115850

DISCLOSURE OF THE INVENTION

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a semiconductor device which can easily and easily peel a resist in a photolithography process of a semiconductor field, A resist stripper composition for a semiconductor substrate which enables the resist to be stripped without adversely affecting the substrate, the substrate, the substrate, the metal layer formed on the substrate, the infrastructure layer and the substrate, and a resist stripping method using the composition.

[Challenge to be solved] None

The present invention is an invention of a resist stripper composition for a semiconductor substrate, which comprises [I] a carbon radical generator, [II] acid, [III] reducing agent and [IV] organic solvent and having a pH of less than 7. The present invention also relates to the use of a resist stripper composition for a semiconductor substrate, which contains a carbon radical generator, a [II] acid, a [III] reducing agent and an organic solvent [IV] The present invention is an invention of a resist peeling method.

The resist stripper composition of the present invention makes it possible to easily and easily peel the resist in the photolithography process of the semiconductor field. The resist stripper composition of the present invention comprises [I] a carbon radical generator, [II] acid, [III] IV] organic solvent in combination makes it possible to peel off the resist without adversely affecting the silicon oxide film, the infra layer, and the metal wiring formed on the substrate under the resist.

The resist stripping method of the present invention is an effective method for peeling off the resist easily and easily. As described above by using the stripping agent of the above composition, the resist stripping method of the present invention does not adversely affect the silicon oxide film, It is possible to easily peel off the resist.

That is, the inventors of the present invention have conducted intensive studies to achieve the above object and as a result have found that by making a composition comprising at least a carbon radical generator [I], a [II] acid, a [III] reducing agent and an organic solvent [ , And the resist can be peeled off. By using a composition containing the above-mentioned components, the resist can be peeled off without employing a method using a large or expensive apparatus such as plasma ashing, It is possible to mildly and easily peel off the resist as compared with the conventional immersion method using caro-acid, and the composition can be a composition that does not contain a component that dissolves metals, Of the present invention can be applied also to a substrate on which a metal wiring of the present invention has been formed. The present invention has been accomplished based on this finding.

In addition, since the carbon radical generator in the resist stripper composition of the present invention is less liable to cause adverse effects such as the formation of an oxide film on the surface of the metal wiring, as compared with a compound that generates carbon radicals such as hydrogen peroxide and ozone, It has also been found by the present inventors that the resist can be peeled off without adversely affecting the wiring. Further, the resist stripper composition of the present invention does not need to contain a compound generating fluorine ion (fluoride ion) such as, for example, hydrogen fluoride or its salt, and has no corrosive action due to hydrogen fluoride or the like, (Silicon oxide film) formed thereon is particularly advantageous as a resist stripping agent on a semiconductor substrate which may be corroded by hydrogen fluoride or the like, such as a silicon substrate on which an oxide film (silicon oxide film) is formed It was discovered by the inventor.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an optical microscope photograph showing a state where there is no deposition or deposition of a resist stripper on a substrate of an embodiment of the present invention. FIG.
Fig. 2 is an optical microscope photograph showing a state where deposition or adherence of a resist release material is observed on a substrate of a comparative example.
3 is a plan view schematically showing a sample used in an embodiment of the present invention.
4 is a plan view schematically showing a sample used in an embodiment of the present invention.

Examples of the [I] carbon radical generator in the resist stripper composition for a semiconductor substrate of the present invention include compounds which suitably generate carbon radicals by heating or light irradiation. Specific examples thereof include 2,2 Azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'- Azobis (cyclohexane-1-carbonitrile), 1 - [(1-cyano-1-methylethyl Azo] formamides such as 2,2'-azobis * 2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] Propionamide, 2,2'-azobis 2-methyl-N- [2- (1-hydroxybutyl)] propionamide, 2,2'-azobis [ ) Propionamide], 2,2'-azobis [N- (2-propenyl) -2-methylpropionamide], 2,2'- Azoamide-based carbon radical generators such as bis (N-butyl-2-methylpropionamide) and 2,2'-azobis (N-cyclohexyl-2-methylpropionamide) Chain azoamidine carbon radicals such as azobis (2-methylpropionamidine) dihydrochloride and 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropionamidine] Azo compounds such as 2,2'-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2'- 2-yl) propane] disulfate, 2,2'-azobis [2- (2-imidazolin- 2-imidazolin-2-yl] propane dihydrochloride, 2,2'-azobis [2- (2-imidazolin- Bis (1-imino-1-pyrrolidino-2-methylpropane) dihydrochloride, cyclic azoamidine carbon radical generators such as And azo ester-based carbon radical generators such as methyl-2,2'-azobis (2-methylpropionate), azo esters such as 4,4'-azobis (4-cyanovaleric acid) A nitrile carboxylic acid-based carbon radical generator, for example, an azoalkyl-based carbon radical generator such as 2,2'-azobis (2,4,4-trimethylpentane), for example, dimethyl Compounds which suitably generate carbon radicals by heating such as a macromolecule-based carbon radical generator such as a polysiloxane compound, such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether , Benzoquaternium carbon radical generators such as 2,2'-dimethoxy-1,2-diphenylethane-1-one, benzophenone carbon radical generators such as benzophenone, 4, 4'-bis (diethylamino) benzophenone, acrylated benzophenone, methyl benzoylbenzoate, 2-benzo Benzophenone-based carbon radical generators such as naphthalene, 4-benzoylbiphenyl, 4-benzoyldiphenyl ether, 1,4-dibenzoylbenzene and [4- (methylphenylthio) phenyl] 2-methyl-1-phenylpropan-1-one, 1-methyl-1-phenylpropan-1-one, 2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- 4- 4- 2-methylpropionyl) benzyl] phenyl} -2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, and other 1,2-hydroxyalkylphenone-based carbon radical generators such as 2 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropane-1-one, - (dimethylamino) -2 - [(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone and the like Aminoalkylphenone-based carbon radical generators such as 2,4,6-trimethylbenzoyl phenyl ethoxyphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2 , 4,6-trimethylbenzoyl) phenylphosphine oxide, anthraquinone-based carbon radical generators such as, for example, ethyl anthraquinone, for example, chlorothioxanthone, Thioxanthone carbon radical generators such as diethyl thioxanthone and isopropyl thioxanthone, and acridone carbon radical generators such as 10-butyl chloroacridone, for example, 2,2 ' Bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'-biimidazole, 2,2'- , Imidazole-based carbon radical generators such as 5'-tetrakis (3,4,5-trimethoxyphenyl) -1,2 ', -bimidazole, for example 1,2-octanedione- - [4- (phenylthio) -2- (o-benzoyloxime)], ethanone-1- [ Oxime ester-based carbon radical generators such as 9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] , And titanocene-based carbon radical generators such as 4-cyclopentadien-1-yl) -bis [2,6-difluoro-3- (1H- And compounds suitably generating carbon radicals. These carbon radical generators may be used singly or in combination of two or more of them.

Of the above-mentioned [1] carbon radical generating agents, those which suitably generate carbon radicals by heating include those capable of generating carbon radicals by irradiation with light, and examples thereof include azonitrile carbon radical generators, A radical azoamidine-based carbon radical generator, a cyclic azo-amidine-based carbon radical generator, and an azo ester-based carbon radical generator can generate carbon radicals by light, It is possible to generate carbon radicals by light irradiation of 200 to 750 nm. That is, the compound which suitably generates carbon radicals by heating can generate carbon radicals only by heating usually as described later. However, the azo-type carbon radical generator, the azoamide-based carbon radical generator, the chain azoamidine- A compound capable of generating a carbon radical by light irradiation such as a radical generator, a cyclic azoamidine-based carbon radical generator, and an azoester-based carbon radical generator can be obtained not only by a heating method alone, Alternatively, carbon radicals may be generated by a combination of heating and light irradiation. On the other hand, a compound that suitably generates carbon radicals by light irradiation means that carbon radicals can be easily released by light irradiation, and does not mean that carbon radicals are not generated by heating. That is, a compound which suitably generates carbon radicals by the light irradiation described above is capable of generating carbon radicals even by heating. Compounds that generate carbon radicals suitably by light irradiation are those capable of generating carbon radicals only by light irradiation, but they can also generate carbon radicals by heating alone or in combination with heating and light irradiation. In addition, the carbon radical generating agents of these preferred embodiments are useful from the viewpoints of industrial availability, economical efficiency, and ability to peel the resist efficiently in a short time.

[1] The action of the [1] carbon radical generator according to the present invention is not clear, but it is necessary to dissolve the surface of the resist and the cured resist film to promote penetration of the organic solvent into the resist as described later, And the solubilization of the solubilizing agent. The [II] acid in the resist stripper composition for a semiconductor substrate of the present invention is not particularly limited as long as it has an action of making the pH of the solution acidic and specifically includes, for example, hydrochloric acid, nitric acid, sulfuric acid, Aliphatic monocarboxylic acids such as formic acid, acetic acid, trifluoroacetic acid, propionic acid, butyric acid, valeric acid, capronic acid, enantic acid, caprylic acid, pelargonic acid, capric acid and lauric acid, Aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid and fumaric acid; aliphatic hydroxycarboxylic acids such as lactic acid, malic acid, tartaric acid, For example, aliphatic tricarboxylic acids such as aconitic acid, aliphatic oxocarboxylic acids such as pyruvic acid, and aromatic monocarboxylic acids such as benzoic acid, for example, Aromatic dicarboxylic acids such as terephthalic acid and the like, aromatic hydroxycarboxylic acids such as salicylic acid and gallic acid, and aromatic acids such as aromatic hexacarboxylic acids such as mellitic acid. The above-mentioned [II] acid may be in the form of a salt as long as it is acidic, and specific examples of the salt include, for example, ammonium salts such as alkali metal salts such as sodium salts and potassium salts. One kind of these acids may be used alone, or a plurality of kinds of these acids may be used in combination. For the sake of convenience, the carboxylic acid having at least one hydroxyl group in the structure is classified into a hydroxycarboxylic acid regardless of the number of carboxyl groups.

Among these [II] acids, organic acids are preferable, and in view of industrial availability and economical efficiency, organic acids such as acetic acid, trifluoroacetic acid, oxalic acid, and citric acid More preferable. The inorganic acid is usually supplied as an aqueous solution in many cases. When such an inorganic acid is used for a substrate on which a metal wiring is formed, the action of a large amount of water and acid contained in the inorganic acid may cause corrosion of the metal wiring. It is preferable that inorganic acid is not used. When an alkali metal salt of an inorganic acid or an organic acid is used for a substrate on which a metal wiring is formed, deterioration of electrical characteristics on the semiconductor substrate may be caused. Therefore, when the resist is peeled off from such a substrate, Is not used.

Although the action of the [II] acid according to the present invention is not clear, it is considered that there is an action to accelerate the solubilization of the resist and the resist cured film into an organic solvent.

The [III] reducing agent in the resist stripper composition for a semiconductor substrate of the present invention is not particularly limited as long as it is a compound having a reducing action, and usually includes a reducing agent used in this field. Specific examples thereof include hydrazine or a derivative thereof such as hydroxylamine or a derivative thereof such as a sulfite such as sodium sulfite or ammonium sulfite such as sodium thiosulfate or ammonium thiosulfate, For example, an aldehyde such as a sulfite such as formaldehyde or acetaldehyde such as formic acid, oxalic acid, succinic acid, lactic acid, malic acid, citric acid or pyruvic acid, for example, ascorbic acid or ascorbic acid ester , Ascorbic acid derivatives such as isoascorbic acid or isoascorbic acid ester such as arabinose, xylose and ribose, and reducing sugars such as glucose, mannose, fructose, galactose and the like And monosaccharides such as hexose sugar having a reducing ability.

These reducing agents may be used singly or in combination of plural kinds thereof. Among the above reducing agents, for example, carboxylic acids having reducibility such as formic acid, oxalic acid, amber oil, lactic acid, malic acid, citric acid and pyruvic acid also exhibit the action as the above-mentioned acid. Therefore, It is also possible to use a carboxylic acid having reducibility singly.

In the above derivative, specific examples of the hydrazine derivative include compounds such as hydrazine sulfate and monohydrochloride hydrate. As specific examples of the hydroxylamine derivative, there may be mentioned, for example,

(Wherein R ¹ represents a linear, branched or cyclic alkyl group of 1 to 6 carbon atoms or a linear or branched alkyl group of 1 to 4 carbon atoms having 1 to 3 hydroxyl groups, and R ² represents hydrogen Atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or a straight or branched alkyl group having 1 to 4 carbon atoms and having 1 to 3 hydroxyl groups), etc. .

Specific examples of the linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms represented by R ¹ and R ² in the general formula [1] include 1-hydroxyethyl group, 2-hydroxyethyl group, Dihydroxyethyl group, a 1-hydroxy-n-propyl group, a 2-hydroxy-n-propyl group, a 3-hydroxy- Dihydroxy-n-propyl group, 2,3-dihydroxy-n-propyl group, 3,3-dihydroxy- Dihydroxy-n-propyl group, 1,2,3-trihydroxy-n-propyl group, 2,2,3-trihydroxy-n-propyl group, 2,3,3-trihydroxy- n-propyl group, 1-hydroxyisopropyl group, 2-hydroxyisopropyl group, 1,1-dihydroxyisopropyl group, 1,2-dihydroxyisopropyl group, N-butyl group, 3-hydroxy-n-butyl group, 4-hydroxynaphthyl group, Roxy-n-butyl Dihydroxy-n-butyl group, 1,4-dihydroxy-n-butyl group, 2,2-dihydroxy-n Dihydroxy-n-butyl group, 3,3-dihydroxy-n-butyl group, 3,4-dihydroxy butyl group, a 1,2,4-trihydroxy-n-butyl group, a 1,2,4-trihydroxy-n-butyl group, Trihydroxy-n-butyl group, 2,2,3-trihydroxy-n-butyl group, 2,2,4-trihydroxy- Trihydroxy-n-butyl group, 3,3,4-trihydroxy-n-butyl group, 2,4,4-trihydroxy-n-butyl group, 3,4,4-trihydroxy-n Butyl group, 2-hydroxy-sec-butyl group, 3-hydroxy-sec-butyl group, 4-hydroxy-sec- Dihydroxy-sec-butyl group, 1, 3-dihydroxy-sec-butyl group, 1, Dihydroxy-sec-butyl group, 2,3-dihydroxy-sec-butyl group, 2,4-dihydroxy- Dihydroxy-sec-butyl group, 4,4-dihydroxy-sec-butyl group, 1-hydroxy-2- n-propyl group, a 2-hydroxy-2-methyl-n-propyl group, a 3-hydroxy- Methyl-n-propyl group, 2,3-dihydroxy-2-methyl-n-propyl group, 3,3-dihydroxy- Hydroxy-2-methyl-n-propyl group, 1,3-trihydroxy-2-methyl- methyl-n-propyl group, a 1,3-dihydroxy-2-hydroxymethyl-n-propyl group, a 2,3-dihydroxy Dihydroxy-2-methylpropyl group, 1-hydroxy-2-methylisopropyl group, 1,3-dihydroxy- And the like. Of these, a 2,2-dihydroxyethyl group, a 2,3-dihydroxy-n-propyl group, a 3,3- N-propyl group is preferable, and 2,2-dihydroxyethyl group and 2,3-dihydroxy-n-propyl group are more preferable among them. Specific examples of the hydroxylamine derivative are usually used in this field . ≪ / RTI >

These hydroxylamine derivatives represented by the above general formula [1] may be commercially available ones, or may be obtained by, for example, dropping an epoxide such as glycidol into an aqueous solution of hydroxylamine or monoalkyl-substituted hydroxylamine Followed by reaction at a suitable temperature, or the like.

Specific examples of the ascorbic acid ester include compounds such as ascorbyl stearate, ascorbyl palmitate, ascorbyl dipalmitate, ascorbyl tetrahexyldecanoate, and glucoside ascorbic acid. Specific examples of the isoascorbic acid ester include stearic acid isoascorbyl, palmitic acid isoascorbyl, dipalmitic acid isoascorbyl, tetrahexyldecanoic acid isoascorbyl, isoascorbic acid glucoside, and the like. Compounds. Among the ascorbic acid ester and isoascorbic acid esters, for example, sodium ascorbate, sodium ascorbic acid sulfate, sodium ascorbic acid phosphate, magnesium ascorbic acid phosphate, sodium isoascorbate, sodium isoascorbic acid sulfate, sodium isoascorbic acid phosphate, When an ascorbic acid ester or an isoascorbic acid ester containing an alkali metal such as magnesium phosphate or an alkaline earth metal is used for a substrate on which a metal wiring is formed, the alkali metal or alkaline earth metal may cause deterioration of electrical characteristics on the metal wiring Therefore, when the resist is peeled off from such a substrate, it is preferable not to use ascorbic acid ester or isoascorbic acid ester containing alkali metal or the like.

Among these [III] reducing agents, hydroxylamine or a derivative thereof, for example, ascorbic acid or ascorbic acid ester, isoascorbic acid or the like is preferable from the viewpoints of suitable reducing performance, industrial availability, Ascorbic acid, and ascorbic acid ester. Among them, diethylhydroxylamine, bis (2,2-dihydroxyethyl) benzoate, Hydroxylamine, bis (2,3-dihydroxy-n-propyl) -1-hydroxylamine, ascorbic acid and ascorbyl palmitate are more preferred.

Although the action of the [III] reducing agent according to the present invention is not clear, it is also possible to chemically react with the resist and the resist cured film by chemically modifying (modifying) the structure of the resist and the resist cured film, It is considered that there is an action to facilitate solubilization. Examples of the organic solvent [IV] used in the resist stripper composition for a semiconductor substrate of the present invention include organic solvents conventionally used in this field. Specific examples thereof include methanol, ethanol, n-propanol, isopropanol alcohol type protonic polar organic solvents such as n-butanol, tert-butanol, 1-methoxy-2-propanol and ethylene glycol such as ethyl acetate, n-propyl acetate, isobutyl acetate, Ester solvents such as diethyl, diethyl tartarate and? -Butyrolactone; amide solvents such as dimethylformamide and N-methylpyrrolidone; sulfoxide-based solvents such as dimethylsulfoxide; And non-protonic polar organic solvents such as nitrile solvents such as acetonitrile. Of these organic solvents, isopropanol, ethylene glycol,? -Butyrolactone, and N-methylpyrrolidone are preferable, and isopropanol,? -Butyrolactone, Ralidone is more preferable. As the organic solvent in the resist stripper composition for semiconductor substrate of the present invention, isopropanol and γ-butyrolactone may be used alone or in combination of two or more. Or a combination of isopropanol and N-methylpyrrolidone is particularly preferable.

The action of the organic solvent [IV] according to the present invention is to dissolve the resist and the resist cured film by dissolving the resist and the resist cured film with the organic solvent.

The resist stripper composition for a semiconductor substrate of the present invention may contain [V] water in addition to the above-mentioned components. By including water, it becomes possible to assist solubilization of a reducing agent or the like, which is difficult to dissolve in an organic solvent, and to exert the reducing action and the like of the reducing agent so that the resist can be easily peeled off. The water of the above [V] is not particularly limited as long as it does not adversely affect the exfoliation of the resist. Examples of the water include water, purified water such as distilled water and deionized water, ultrapure water and the like, desirable. Since the ultrapure water contains almost no impurities, it can be suitably used for a substrate on which a metal wiring such as an aluminum wiring is formed. The resist stripper composition for a semiconductor substrate of the present invention may further contain a surfactant of the [IV] in addition to the above-mentioned components. By incorporating the surfactant, solubilization of a reducing agent or the like, which is hardly dissolved in the organic solvent, is assisted, and the reducing action of the reducing agent can be exerted smoothly, so that the resist can be easily peeled off.

The resist stripper composition for a semiconductor substrate of the present invention can dissolve the resist by incorporating a [II] acid so that the pH is made acidic to less than 7. Further, in the pH of the acidic region, a pH in the range of 0 to 4 is preferable, and a pH in the range of 0 to 2 is more preferable. By setting the pH to such a preferable range, the resist can be peeled off more efficiently in a shorter time. The pH may be adjusted by appropriately adjusting the type and concentration of the acid.

The resist stripper composition for a semiconductor substrate of the present invention contains a [I] carbon radical generator, a [II] acid, a [III] reducing agent and an organic solvent [IV] It may be.

The resist stripper composition for a semiconductor substrate of the present invention is in the form of an organic solvent solution or a mixed solution of an organic solvent and water, wherein the above-mentioned carbon radical generator, acid and reducing agent are mixed with an organic solvent or an organic solvent and water In a mixed solvent. In the resist stripper composition for a semiconductor substrate of the present invention, in addition to the essential constituents, the weight% concentration of each component in the composition containing water, that is, [I] carbon radical generator, [II] The weight% concentration of the reducing agent, [IV] organic solvent and [V] water will be described below.

The weight% concentration of the [I] carbon radical generator in the resist stripper composition for a semiconductor substrate of the present invention is usually 0.1 to 10% by weight, preferably 0.5 to 10% by weight, based on the total weight of the composition, 10% by weight. When the concentration of the carbon radical generator used is too low, carbon radicals necessary for peeling the resist are inevitably reduced, and the resist can not be sufficiently peeled off. The concentration by weight of the [II] acid in the resist stripper composition for a semiconductor substrate of the present invention is usually 0.1 to 5% by weight, preferably 0.5 to 5% by weight, based on the total weight of the composition. When the concentration of the acid used is too low, the pH of the composition becomes too high, which makes it difficult to peel the resist in a short time and effectively.

The weight% concentration of the [III] reducing agent in the resist stripper composition for a semiconductor substrate of the present invention is usually from 0.01 to 10% by weight, preferably from 0.1 to 5% by weight, based on the weight of the reducing agent relative to the total weight of the composition. If the concentration of the reducing agent used is too low, there is a problem that the resist can not be fully peeled off.

The weight% concentration of the organic solvent in the resist stripper composition for semiconductor substrate of the present invention is usually 60 to 99% by weight, preferably 70 to 99% by weight, based on the total weight of the composition . If the concentration of the organic solvent used is too low, there is a problem that the resist can not be sufficiently peeled off or the peeled resist residue adheres to the substrate. The concentration by weight of [V] water in the resist stripper composition for semiconductor substrate of the present invention is usually 0.01 to 30% by weight, preferably 0.01 to 20% by weight, relative to the total weight of the composition. If the concentration of water used is too high, corrosion of metal wiring such as aluminum wiring formed on the substrate may occur. Therefore, when the substrate to be resist stripped is a substrate on which a metal substrate is formed, the water content is preferably very small. The resist stripper composition for a semiconductor substrate of the present invention may contain the [I] carbon radical generator, [II] acid, [III] reducing agent, [IV] organic solvent, [V] water and [IV ] In addition to the surfactant, various auxiliary components may be contained within a range not hindering the effect of the present invention.

Specific examples of the various auxiliary components include a metal corrosion inhibitor which is used for protecting a metal wiring and preventing corrosion when a substrate on which a metal wiring is formed is targeted. Specific examples of the metal corrosion inhibitor include, for example, benzotriazoles such as benzotriazole derivatives such as carboxybenzotriazole and aminobenzotriazole, thioureas such as thioureas, for example, , Mercaptothiazole, melaptoethanol, thioglycerol and the like, and carboxylic acid derivatives such as quinolinecarboxylic acid. These metal corrosive agents may be used singly or in combination of plural kinds thereof.

The concentration of the auxiliary component to be added to the resist stripper composition for semiconductor substrate of the present invention may be generally in the range of concentrations used in this field. Specifically, for example, the concentration by weight of the metal corrosion inhibitor may be By weight, based on the weight of the metal corrosion inhibitor.

The method for preparing a resist stripper composition for a semiconductor substrate of the present invention may be a method capable of finally preparing a solution containing the component according to the present invention as described above. Specifically, for example, (1) the carbon radical generator, the [II] acid and the [III] reducing agent according to the present invention and, if necessary, the [IV] surfactant are directly added to the organic solvent [IV] , (2) an organic solvent in which the [I] carbon radical generator, the [II] acid and the [III] reducing agent according to the present invention and, if necessary, the [IV] surfactant are separately dissolved in an organic solvent [3] A method of mixing a carbon radical generator, a [II] acid and a [III] reducing agent according to the present invention, [IV] (II) acid and (III) acid according to the present invention are added to an organic solvent solution of (IV) in which a carbon radical generator of the present invention is dissolved; (4) A reducing agent and, if necessary, a [V] aqueous solution in which the [IV] surfactant is dissolved. Among them, the method (4) is a preferable preparation method since the pH is adjusted easily since an aqueous solution containing an acid is finally added. In addition, since the resist stripper composition for a semiconductor engine of the present invention contains a carbon radical generator, the carbon radical generator such as a yellow lamp is irradiated with light having a wavelength of a specific region, which is required for generating carbon radicals, It is preferable to prepare it at a low temperature such as room temperature or the like. Next, a preferable example of a resist and a semiconductor substrate according to a preferred embodiment of the present invention, which is a subject to be peeled off, in the resist stripper composition for a semiconductor substrate of the present invention will be described. The resist to be peeled off in the resist stripper composition for a semiconductor substrate of the present invention is a photoresist film formed from a resist material containing so-called organic polymer compound and is used for an excimer laser such as g-line, i-line, KrF and ArF, , And X-rays, and is not particularly limited, and includes a film denatured by heat, for example, a film in which the surface is hardened by plasma doping such as boron or phosphorus. Thus, the resist stripper composition for a semiconductor substrate of the present invention is an excellent stripper capable of not only removing a resist but also a resist-cured film formed by plasma doping. As a specific example of a semiconductor substrate to be an object of the resist stripper composition for a semiconductor substrate of the present invention, for example, a silicon substrate, a GaAs substrate, a Gap substrate and the like can be mentioned. Is preferably a silicon substrate having an oxide film (silicon oxide film) formed on the surface of the substrate.

The oxide film referred to herein is a thermal oxide film, a TEOS oxide film, or the like.

The semiconductor substrate to be an object of the resist stripper composition for a semiconductor substrate of the present invention may be a silicon substrate or the like as long as at least a resist is formed on a semiconductor substrate such as the one described above. A substrate formed on an upper portion of the substrate. Among them, it is more preferable that the silicon substrate on which the oxide film is formed is a plasma-doped substrate.

The semiconductor substrate to be a target may have a metal wiring. Among them, a semiconductor substrate having a metal wiring is preferable. Among them, a silicon substrate having a metal wiring is more preferable. Among them, (Silicon oxide film) formed thereon is particularly preferable. Specific examples of the metal wiring include aluminum wiring, tungsten wiring, copper wiring, aluminum alloy wiring, tungsten alloy wiring, aluminum copper alloy wiring and the like. The resist stripper composition for a semiconductor substrate of the present invention can be used as a resist stripper composition for a semiconductor substrate which is capable of forming a composition containing only a small amount of water or not containing it at all and also having an adverse effect such as oxidizing the wiring surface of a metal wiring It is possible to form a composition that does not contain a compound that generates a carbon radical (carbon radical generator) at all. Therefore, even if a substrate having a metal wiring is formed, it is an excellent stripper that can peel off the resist without corroding the metal wiring.

As described above, since the resist stripper composition for a semiconductor substrate of the present invention can be suitably used for a silicon substrate having an oxide film formed on its surface, a silicon oxide film such as hydrogen fluoride or its salt is dissolved , It is preferable that the fluorine-containing compound does not substantially contain a compound capable of generating fluorine ions (fluoride ions). In the resist stripper composition for a semiconductor substrate of the present invention, by virtue not containing a compound that generates such a highly corrosive fluorine ion (fluoride ion), handling of the composition is facilitated and waste solution treatment is facilitated The effect can also be expected. The term " substantially " as used herein refers to an amount that is likely to adversely affect the silicon oxide film, such as dissolving the silicon oxide film, and does not exclude a trace amount of the impurity.

[0058] Next, preferable means of a method for removing a resist by treating a semiconductor substrate formed with a resist using the resist stripper composition for a semiconductor substrate of the present invention will be described.

First, as the resist stripper composition for a semiconductor substrate of the present invention, a solution of the composition of the present invention prepared as described above in a predetermined concentration range by the method as described above is prepared. Subsequently, for example, a method of immersing the semiconductor substrate as described above while irradiating light of a predetermined wavelength (active energy ray) to the solution, a method of immersing the semiconductor substrate as described above while heating the solution to a predetermined temperature, A method of immersing a semiconductor substrate such as the one described above, and a method of immersing the above-described semiconductor substrate in combination with the above light irradiation and the above-mentioned heating.

A preferable wavelength of light (active energy ray) in the case of irradiating a predetermined light (active energy ray) is a wavelength of 200 to 750 nm, preferably 200 to 450 nm. By irradiating the resist stripper composition for a semiconductor substrate of the present invention with light (active energy ray) having such a preferable range of wavelengths, carbon radicals are efficiently generated from the carbon radical generator according to the present invention, The resist can be effectively removed.

The preferred temperature for heating in the case of heating to a predetermined temperature is usually 30 to 90 占 폚, preferably 40 to 80 占 폚. By heating the resist stripper composition for a semiconductor substrate of the present invention so that the temperature is within such a preferable range, carbon radicals are efficiently generated from the carbon radical generator according to the present invention, and the resist stripper composition can be removed more efficiently .

The resist stripper composition for semiconductor substrate of the present invention (composition subjected to light irradiation only) irradiated with light of the same wavelength as above (active energy line), resist stripper for semiconductor substrate of the present invention heated to a predetermined temperature as described above The resist stripper composition for a semiconductor substrate of the present invention heated at the above-mentioned temperature while irradiating the composition (composition subjected to heating only) or light having the same wavelength as above (active energy ray) Is preferably 1 to 60 minutes, more preferably 1 to 50 minutes, and still more preferably 1 to 40 minutes. Among the above-mentioned methods, the method using only light irradiation is more likely to inhibit the generation of carbon radicals of the carbon radical generating agent than the heating alone method or the heating method, and it is difficult to adversely affect the semiconductor substrate, It is advantageous in terms of cost performance, and the like. Therefore, when the resist is peeled off, it is preferable to employ a method of irradiating light (active energy ray) having a desirable wavelength as described above to the resist stripper composition for semiconductor substrate of the present invention but not heating it. In a case where it is necessary to efficiently strip the resist in a shorter time, it may be preferable to use the resist stripper composition for semiconductor substrate of the present invention in which light irradiation and heating are used in combination.

Specific examples of the immersing method include, for example, a method of simply leaving the semiconductor substrate in the resist stripper composition for semiconductor substrate of the present invention during immersion, for example, a method of immersing the resist stripper composition for semiconductor substrate of the present invention For example, a method of immersing the composition in an oscillating state such as a method of immersing the resist stripper composition for semiconductor substrate of the present invention while bubbling it with an inert gas such as nitrogen gas, for example, a method of immersing the semiconductor substrate in a conveyer And a method of immersing the semiconductor substrate while rocking the semiconductor substrate such as a method of immersing the substrate while moving using a moving means of the immersion method. Any of the immersion methods may be employed.

The method of peeling the resist as described above is only an example, so other methods may be employed. For example, a method of immersing a semiconductor substrate in a resist stripping composition for a semiconductor substrate of the present invention, which has been previously irradiated with light before immersion, may be employed without performing light irradiation during immersion even with immersion by light irradiation. A method of immersing the semiconductor substrate in the resist stripping composition for a semiconductor substrate of the present invention, which is set at a predetermined temperature before immersion, without adding heat during immersion, for example, even in the immersion method by heating may be employed . Although the method of peeling the resist by immersion is described here, a method of applying or spraying the resist stripping agent composition for semiconductor substrate of the present invention, which has been heated or irradiated by the enemy, may be employed instead of the immersion method . In addition, devices required for light irradiation, heating, immersion, stirring, bubbling, coating, spraying, and the like are usually sufficient for use in this field.

As described above, the resist stripping method of the present invention is an excellent method which can peel off the resist under mild conditions such as light control and heating without employing the conventionally performed plasma ashing. Further, the resist stripping method of the present invention Since the composition can be a composition that does not contain a compound that generates fluorine ions (fluoride ions), which is a component capable of dissolving a silicon oxide film or a metal, it is also applicable to a silicon substrate on which a silicon oxide film is formed or a semiconductor substrate on which a metal wiring is formed It is an excellent method.

EXAMPLES Hereinafter, the present invention will be specifically described based on examples and comparative examples, but the present invention is not limited to these examples. In the following examples, percentages are based on weight (w / w%) unless otherwise specified. A surface of a silicon wafer having a diameter of 300 mm was coated with a resist film having a thickness of 200 mm on an upper surface of a substrate on which an oxide film was formed and then the surface of the resist film was cured by plasma doping with boron to form a substrate with a cured resist film ). Subsequently, the substrate was cut into pieces of 20 mm x 20 mm to form a piece, which was used as an evaluation substrate.

Preparation of Resist Remover Composition (1) for Semiconductor Substrate of the Present Invention Under irradiation of a yellow lamp (introductory yellow fluorescent lamp, FLR40SY-IC / M, manufactured by Mitsubishi Electric Corporation) to 80 g of? -Butyrolactone in an organic solvent solution, dimethyl Azobis (2-methylpropionate) (V-601, manufactured by Wako Pure Chemical Industries, Ltd.) was added thereto, and the mixture was stirred at room temperature. After the dissolution of V-601 was confirmed, the entire amount of an aqueous solution prepared by dissolving 0.5 g of ascorbic acid and 3 g of citric acid in 15.5 g of water was added to the solution while stirring to prepare the composition (1) of the present invention having pH 2 Respectively.

Preparation of Resist Remover Compositions (2) to (10) for Semiconductor Substrate of the Present Invention In Examples 2 to 10, the same components as shown in Table 1 were used and the amounts shown in Table 1 were used. The compositions (2) to (10) of the present invention were prepared. These compositions were combined with the composition of Example 1 and are shown in Table 1. Further, the numerical values shown in Table 1 are the% by weight of each component when the total weight of the composition is taken as 100%.

Comparative Example 1 Preparation of Comparative Composition (1) After adding 0.5 g of ascorbic acid to a mixed solvent of 80 g of? -Butyrolactone and 16.5 g of water, 3 g of citric acid was added to obtain a comparative composition (1 ) Was prepared.

COMPARATIVE EXAMPLE 2 Preparation of comparative compositions (2) to (5) Comparative Example 2 was repeated except that the components shown in Table 2 were used and the amounts shown in Table 2 were used, Except that the base shown in Table 2 was used in place of the acid relating to the composition of the present invention and the amounts shown in Table 2 were used in Comparative Examples 3 to 5, (3) to (5) were prepared in the same manner as in Comparative Examples. These compositions are combined with the composition of Comparative Example 1 and shown in Table 2.

Further, the numerical values shown in Table 2 are the weight% concentration of each component when the total weight of the composition is taken as 100%.

Evaluation of Resist Remover Composition (1) for Semiconductor Substrate of the Present Invention 100 mL of the composition (1) of the present invention prepared in Example 1 was heated to 60 占 폚 and maintained at 60 占 폚 while keeping the evaluation substrate at 30 Lt; / RTI > Thereafter, the substrate was rinsed with pure water for 30 seconds, and the surface of the substrate was dried with compressed air. The substrate sample after drying was visually observed, and it was confirmed that the resist was satisfactorily peeled off. As a result, it was found that not only the resist film but also the resist-cured film could be peeled off when the substrate for evaluation was immersed in the heated composition of the present invention with stirring for 30 minutes.

Evaluation of the semiconductor surface treatment composition (2) to (9) of the present invention In Examples 12 to 19, the compositions (2) to (9) of the present invention were immersed for a predetermined time in the same manner as in Example 11 , And the peeling performance of the resist was visually observed. These results are combined with the results of Example 11 and are shown in Table 3.

 Evaluation of Resist Remover Composition (10) for Semiconductor Substrate of the Present Invention An ultraviolet irradiator (UV irradiator, MUV-35U MUV-PF001 filter, fitted with a filter) was placed in 100 mL of the composition (10) of the present invention prepared in Example 10, (Active energy ray) at a center wavelength of 320 nm, and the substrate for evaluation was immersed for 20 minutes under gentle stirring. Thereafter, the substrate was rinsed with pure water for 30 seconds, and the surface of the substrate was dried with compressed air. The substrate sample after drying was visually observed, and it was confirmed that the resist was satisfactorily peeled off. As a result, it was found that not only the resist film but also the resist-cured film could be peeled off when the substrate for evaluation was irradiated with light and immersed in the composition of the present invention for 20 minutes under agitation.

The resist stripper composition for a semiconductor substrate of the present invention makes it possible to peel a resist in a photolithography process of a semiconductor field easily and efficiently and also to make it possible to peel off a resist cured film generated in plasma doping . In addition, since the metal wiring formed on the semiconductor substrate is not adversely affected, the resist stripper composition for a semiconductor substrate of the present invention can be expected to be suitably used for a semiconductor substrate on which a metal wiring is formed. In addition, since a composition containing no fluorine ion (fluoride ion) such as hydrogen fluoride or a salt thereof having high corrosiveness can be used, the resist stripper composition for a semiconductor substrate of the present invention can be used as a composition of the composition It is expected that it can be suitably applied to a silicon substrate on which an oxide film (silicon oxide film) is formed which is easy to handle and not only facilitates waste liquid treatment but also is likely to be corroded by hydrogen fluoride or the like.

The resist stripping method of the present invention is a method which can peel the resist easily and efficiently under a relatively mild condition. Therefore, it is necessary to carry out a treatment which requires a large-sized and expensive apparatus such as ashing which has been performed conventionally, It is possible to peel off the resist without peeling in a condition where there is a possibility of adversely affecting the metal wiring, such as dissolution of the metal wiring using the hot mixed acid of the resist, surface oxidation or the like.

Claims (10)

[I] A resist stripper composition for a semiconductor substrate, comprising a carbon radical generator, [II] acid, [III] reducing agent, and [IV] organic solvent and having a pH of less than 7. The composition according to claim 1, further comprising [V] water. The composition according to claim 2, further comprising [IV] a surfactant. The composition according to claim 1, wherein the [I] carbon radical generator is a compound which generates carbon radicals by light irradiation at a wavelength of from 200 to 750 nm. The composition of claim 1, wherein the [II] acid is an organic acid. The composition according to claim 1, wherein the [II] acid is at least one selected from the group consisting of acetic acid, trifluoroacetic acid, oxalic acid and citric acid. The composition according to claim 1, wherein the [III] reducing agent is at least one selected from the group consisting of a hydroxylamine derivative, ascorbic acid, and ascorbic acid ester. The composition of claim 1 wherein the pH is in the range of 0 to 4. The composition according to claim 1, wherein the semiconductor substrate is a silicon substrate having an oxide film formed thereon. The composition according to claim 1, wherein the semiconductor substrate is a silicon substrate on which an oxide film is formed, and a resist is formed on the oxide film.

Images