KR20080076016A - Photoresist stripper composition and exfoliation method of a photoresist using it - Google Patents

Abstract

A composition for stripping a photoresist, and a method for stripping a photoresist by using the composition are provided to remove a photoresist residue without corrosion after hard baking, plasma etching and high temperature ashing. A composition for stripping a photoresist comprises 5-50 wt% of an alkali compound; 1-40 wt% of a water-soluble polar solvent compound; 5-40 wt% of an alkylene glycol alkyl ether compound; 5-40 wt% of deionized water; 0.1-10 wt% of alpha-hydroxycarboxylic acid; 0.1-10 wt% of an aromatic compound containing a hydroxyl group; 0.01-5 wt% of a sulfur-containing anticorrosive having a mercapto group; and optionally 0.01-5 wt% of a linear polyvalent alcohol. Preferably the composition has a pH of 9-12.

Description

Photoresist stripping composition and stripping method using the same {PHOTORESIST STRIPPER COMPOSITION AND EXFOLIATION METHOD OF A PHOTORESIST USING IT}

The present invention relates to a photoresist stripping composition and a photoresist stripping method using the same, and more particularly, to an alkali composition for stripping a resist film from a substrate and a photoresist stripping method using the same in a semiconductor device manufacturing process. will be.

The manufacture of a semiconductor device includes a process of forming a metal film or an insulating film layer, a process of forming a photoresist layer, an exposure process of transferring a mask pattern to the photoresist, an etching process of etching the film along the pattern, and a peeling of removing the photoresist. The process proceeds. In recent years, as the wiring spacing has narrowed, dry etching and high temperature ashing processes using reactive gases have become important processes in the semiconductor process, and some residual residues caused by these processes, that is, polymers, are strongly applied to the insulating film or the metal film. The phenomenon of adhesion appears. Such photoresist residues, ie, polymers, are usually removed with a photoresist stripper.

The ion implantation process, which forms the source / drain at the front of the production line during the semiconductor process, is a process of accelerating into the silicon by injecting ions of Group 3 or Group 5 into an electric field to have energy that is large enough to penetrate the surface of the silicon. It is a process performed for the purpose of partially changing the electrical properties such as conductivity, threshold voltage by doping ions.

To form the source / drain regions, a high dose amount of ion implantation is performed, thereby accelerating the curing of the upper portion of the photoresist and thus removing the photoresist is very difficult. When the high temperature ashing treatment is performed to remove the photoresist, the volume of the photoresist decreases, but since the curing of the photoresist film is intensified and the polymer is formed by the puffing action due to the pressure increase inside the photoresist, they are difficult to remove. .

As a peeling solution for removing the photoresist film, the polymer remaining after the plasma etching or high temperature ashing process, and the cured photoresist after ion implantation, a composition composed of an amine release agent and a hydroxyl amine compound has been proposed. For example, US Pat. No. 4,617,251 discloses certain amine compounds [eg, 2- (2-aminoethoxy) ethanol, 2- (2-aminoethylamino) ethanol, or mixtures thereof) and polar solvents such as N -Methyl-2-pyrrolidone (NMP), tetrahydrofurfuryl alcohol, dimethylglutarate, sulfolane, gamma-butyllactone (GBL), N, N-dimethylacetamide and mixtures thereof) A topographic photoresist stripping composition is disclosed, and US Pat. No. 5,279,771 discloses a stripping composition comprising hydroxylamine, alkanolamine and any polar solvent.

However, the amine-based peeling solution does not completely remove the residual polymer or the photoresist cured after ion implantation after plasma etching, high temperature ashing, or the corrosion of a metal film such as aluminum has serious problems.

In addition, a photoresist composition composed of an alkali compound, a carboxylic acid, water, and the like separately from the amine peeling solution as described above has been proposed. For example, Japanese Patent Laid-Open No. 11-125916 discloses a release agent composed of amine, water, α-Hydroxycarbonic acid, an organic solvent, and the like, and Japanese Patent Laid-Open No. 11-174690 discloses alkanolamines. , Sidewall removal liquid consisting of organic acid, and water, and Korean Patent Publication No. 10-0503702 discloses one or more basic compounds selected from carboxyl group-containing acidic compounds, alkanolamines, and certain quaternary ammonium hydroxides, A photoresist stripper containing a sulfur-containing anticorrosive and water and having a pH of 3.5 to 5.5 is disclosed.

However, these compositions have problems such as plasma etching or high temperature ashing during the highly integrated semiconductor device fabrication process, poor polymer and cured photoresist removal after ion implantation, or corrosion of an insulating film such as metal film or polysilicon. The higher performance peeling agent is calculated | required.

Therefore, the present invention can be used in a stripping process that effectively removes photoresist and polymer remaining after hard baking, plasma etching, and high temperature ashing during the film formation process in the middle line and the production line at the end of semiconductor device manufacturing without corrosion of film quality. Rather, to provide a photoresist stripping composition and a peeling method using the same, which plays an excellent role in the peeling process of the cured photoresist after the ion implantation process of doping the impurities to form the source / drain region in the front end of the production line The purpose.

The present invention is 5 to 50% by weight of the alkali compound, 1 to 40% by weight of the water-soluble polar solvent compound, 5 to 40% by weight of the alkylene glycol alkyl ether compound, 5 to 40% by weight of deionized distilled water, α -A photoresist stripping composition comprising 0.1 to 10% by weight of hydroxycarboxylic acid, 0.1 to 10% by weight of an aromatic compound containing a hydroxyl group, and 0.01 to 5% by weight of a sulfur-containing anticorrosive agent containing a mercapto group and the same It relates to the peeling method used.

The peeling composition of the present invention may further include a straight-chain polyhydric alcohol.

Moreover, it is preferable that pH of the peeling composition of this invention is 9-12.

The alkali compound used in the peeling composition of the present invention is an alkanolamine compound selected from the group consisting of a primary amino alcohol compound, a secondary amino alcohol compound, and a tertiary amino alcohol compound or a specific quaternary ammonium hydroxide. Preference is given to compounds or mixtures thereof. Specific examples include mono-, di-, or tri-ethanolamine, mono-, di-, or tri-propanolamine, mono-, di-, or tri-isopropanolamine, butanolamine, N-butylethanolamine, N- Methylethanolamine, N-ethylethanolamine, triisopropanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, monomethyltripropylammonium hydroxide , (2-hydroxyethyl) tripropylammonium hydroxide, (1-hydroxypropyl) trimethylammonium hydroxide or mixtures of two or more thereof are preferable, and monoethanolamine, N-methylethanolamine, isopropanolamine , Tetramethylammonium hydroxide, tetraethylammonium hydroxide or a mixture of two or more thereof is particularly preferred.

The content of the alkali compound in the peeling composition of the present invention is preferably 5 to 50% by weight based on the total weight of the composition. In this case, when included in less than 5% by weight, the peeling effect on the cured photoresist is inferior, and when included in excess of 50% by weight, it is disadvantageous in terms of environmental aspects, processing cost, and removal of the polymer.

In the peeling composition of the present invention, the water-soluble polar solvent compound is a solvent having excellent solubility in the polymer resin, N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), Dimethyl sulfoxide (DMSO), dimethyl acetamide (DMAc), dimethylformamide (DMF), tetrahydrofurfuryl alcohol, isophorone, diethyl adipate, dimethyl glutarate, sulfolane, gamma-butyllactone (GBL) And mixtures of two or more thereof, and the like, and N-methylpyrrolidone (NMP), dimethyl sulfoxide (DMSO), gamma-butyllactone (GBL), dimethylacetamide (DMAc) and the like are particularly preferable.

The content of the water-soluble polar solvent compound in the peeling composition of the present invention is preferably 1 to 40% by weight based on the total weight of the composition. At this time, when included in less than 1% by weight, the dissolving ability of the peeling solution to the cured or polymer-modified photoresist is reduced, and when included in excess of 40% by weight, the content of other compounds exhibiting a peeling effect is relatively low, resulting in a peeling effect. It causes falling.

In the peeling composition of the present invention, the alkylene glycol alkyl ether compounds include ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, Triethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate or mixtures of two or more thereof are preferred, in particular diethylene glycol Monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monomethyl ether, or mixtures of two or more thereof are preferred.

The content of the alkylene glycol alkyl ether compound in the peeling composition of the present invention is preferably 5 to 40% by weight based on the total weight of the composition. In this case, when the amount is less than 5% by weight, the problem of deterioration in dissolving ability of the photoresist cured or polymer-denatured due to dry etching and ashing occurs. do.

 In the peeling composition of the present invention, the content of deionized distilled water is preferably 5 to 40% by weight based on the total weight of the composition. At this time, when the content is less than 5% by weight, the activity of the compound acting as the peeling of the cured or polymer-modified photoresist decreases, and the peeling effect is deteriorated. The content of the compound is relatively low, causing the peeling effect to drop.

In the composition for peeling, the α-hydroxycarboxylic acid is preferably glycolic acid, lactic acid, α-hydroxyisolactic acid, tartaric acid, or a mixture of two or more thereof.

In the peeling composition of the present invention, the content of α-hydroxycarboxylic acid is preferably 0.01 to 10% by weight based on the total weight of the composition. At this time, when contained in less than 0.01% by weight, the ability to oxidize and remove the polymer resulting from the dry etching and ashing process from the metal film or the insulating film is inferior, and when contained in excess of 10% by weight, the water-soluble organic amine in the peeling solution Not only reduces the photoresist decomposition ability, but also causes corrosion of the metal film or the insulating film.

In the peeling composition of the present invention, the aromatic compound containing a hydroxyl group is preferably hydroquinone, catechol, resorcinol, pyrogallol, methyl calate, gallic acid or a mixture of two or more thereof.

In the peeling composition of the present invention, the content of the aromatic compound containing a hydroxyl group is preferably 0.1 to 10% by weight based on the total weight of the composition. In this case, when included in less than 0.1% by weight may cause corrosion of the metal film such as aluminum, and when included in excess of 10% by weight may be a cost burden of the composition as well as may cause phase separation.

In the peeling composition of the present invention, the sulfur-containing anticorrosive agent containing a mercapto group is preferably ammonium thiosulfate, thioglycerol, thioglycolic acid, thioacetic acid, thiosalicylic acid, or a mixture of two or more thereof.

In the peeling composition of the present invention, the content of the sulfur-containing anticorrosive agent containing a mercapto group is preferably used in 0.01 to 5% by weight based on the total weight of the composition. In this case, when included in less than 0.01% by weight, it causes corrosion of a metal film or an insulating film such as tungsten, and when included in an amount of more than 5% by weight, the removal of photoresist and polymer by an alkali compound or an organic solvent is weakened.

The straight-chain polyhydric alcohol compound which may be additionally included in the peeling composition of the present invention may include solitol, xylitol, mannitol, threazole, or a mixture of two or more thereof as a component for preventing corrosion of the metal film. It is preferably included in 0.01 to 5% by weight relative to the total weight. At this time, when included in less than 0.01% by weight can not expect the corrosion protection effect of the metal film, such as aluminum, if contained in more than 5% by weight there is a problem that complete dissolution of the straight-chain polyhydric alcohol is not made.

The peeling composition of the present invention preferably has a pH of 9 to 12, when the pH of the composition is less than 9 there is a problem that the peeling force is weak, when the pH exceeds 12 there is a problem that the corrosion to the metal proceeds rapidly have.

The peeling composition of the present invention may further include a pH adjusting agent if necessary. Examples of such pH regulators include ammonium salts such as ammonium phosphate and ammonium sulfate, and may be used alone or in combination of two or more thereof.

The composition of the present invention can be used for the stripping process of effectively removing the photoresist and polymer remaining after hard baking, plasma etching, and high temperature ashing during the film forming process in the middle line and the production line at the end of the semiconductor device manufacturing. It may also play an excellent role in the cured photoresist stripping process after the ion implantation process of doping impurities to form source / drain regions in the shearing process.

The release composition of the present invention may be prepared by advantageously mixing the above-mentioned compounds in a predetermined amount, and the mixing method is not particularly limited and various known methods may be applied.

The present invention also provides a stripping method that can effectively remove the polymer remaining after the hard baking, plasma etching, high temperature ashing and the cured photoresist after the ion implantation process.

The peeling method can be carried out by methods commonly known in the art, and a good result can be obtained as long as the peeling solution can be brought into contact with a substrate having a cured or polymer-modified photoresist. As the peeling method according to the present invention, deposition, spraying, or a method using deposition and spraying is applied. When peeling by immersion, spraying, or immersion and spraying, as the peeling conditions, the temperature is usually 10 to 100 ° C, preferably 20 to 80 ° C, and the deposition, spraying, or deposition and spraying time is usually 30 seconds to 40 Minutes, preferably 1 minute to 20 minutes, but are not strictly applied in the present invention and can be carried out by those skilled in the art in easy and suitable conditions.

Hereinafter, the present invention will be described in more detail with reference to Examples and Test Examples. However, the scope of the present invention is not limited by the following examples and test examples.

Example  1-6 and Comparative example  1-6: Photoresist  Preparation of Peeling Composition

By mixing the composition and content as shown in Table 1, 2 to prepare a photoresist stripping composition of Examples 1-6 and Comparative Examples 1-6.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 MEA 35 35 30 20 10 - TMAH (20%) - - - - - 20 NMP 15 15 20 20 25 35 BDG 25 25 25 35 25 20 H ₂ O 18 18 20 18 27.5 15 Garlic acid 3 - - - - - Catechol - 3 One 2 2 5 Glycolic acid 3 - 3 One 10 3 Lactic acid - One - - - - Thioglycerol One One One 2 0.5 2 Sorbitol - 2 - 2 - - PH of composition 10.98 11.30 10.88 10.90 9.61 10.65

Unit: weight%

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 MEA 60 30 30 30 5 5 - HA 15.4 - - - - - - NMP - 25 25 25 10 - - BDG - 20 20 20 10 - - H ₂ O 21.4 20 19 19 62.6 84.6 - Catechol 3.2 5 5 - 2 - - Glycolic acid - - - - 10 - - Acetic acid - - One 5 - 10 - Thioglycerol - - - One 0.4 0.4 - Sulfuric acid - - - - - - 80 Hydrogen peroxide - - - - - - 20 PH of composition 11.36 11.46 11.30 10.90 5.41 4.5 <1

Unit: weight%

MEA: Monoethanolamine

TMAH: Tetramethylammonium Hydroxide

HA: hydroxylamine

NMP: N-methylpyrrolidine

BDG: Diethylene Glycol Monobutyl Ether

Test Example  1: Peel Ability and Corrosion Test

(1) Peeling ability and corrosion test

After the hardened photoresist film and the residues remaining after plasma etching or high temperature ashing were deposited on the metal film or the insulating film, the specimen was immersed in a stripping solution at a temperature of 65 ° C. for 20 minutes. After drying using nitrogen gas. In addition, the scanning electron microscope was used to evaluate the removal of the cured photoresist film and residual residue and the corrosion of the metal film and the insulating film exposed to the chemical liquid. Removability and corrosion evaluation was specified based on the following criteria and the results are shown in Table 3 below.

Peel Ability Evaluation Criteria

O: When polymer remaining on or around metal, pad, via hole or surface is completely removed

△: 70% or more of polymer remaining around or on the surface of metal, pad, via hole

X: Almost no polymer remaining around or on metal, pad, via hole or surface

Corrosion Evaluation Criteria

O: No corrosion on metal, upper and lower sides of pad

(Triangle | delta): When there is partial corrosion in metal, the upper and lower parts of a pad, and a side surface

X: When there is much corrosion on metal, upper and lower sides of the pad

Example Comparative example One 2 3 4 5 6 One 2 3 4 5 6 7 Peelability O O O O O O O △ O O X X O causticity O O O O O O X △ X X △ X X

The peeling composition of the present invention can effectively remove the photoresist and polymer remaining after hard baking, plasma etching, and high temperature ashing during the film formation process of the middle line and the production line at the end of the semiconductor device manufacturing, without corrosion of film quality. The exfoliation process of the cured photoresist is excellent after the ion implantation process of doping the impurity to form the source / drain regions in the front end of the production line.

Claims (11)

5-50 weight% of alkali compounds, 1-40 weight% of water-soluble polar solvent compounds, 5-40 weight% of alkylene glycol alkyl ether compounds, 5-40 weight% of deionized distilled water, (alpha) -hydroxy The composition for photoresist peeling containing 0.1-10 weight% of carboxylic acids, 0.1-10 weight% of aromatic compounds containing a hydroxyl group, and 0.01-5 weight% of sulfur-containing anticorrosive agents containing a mercapto group. The composition for peeling photoresist according to claim 1, further comprising 0.01 to 5% by weight of a linear polyhydric alcohol compound. The photoresist peeling composition according to claim 1, wherein the pH is 9 to 12. The compound of claim 1, wherein the alkali compound is mono-, di-, or tri-ethanolamine, mono-, di-, or tri-propanolamine, mono-, di-, or tri-isopropanolamine, butanolamine, N- Butylethanolamine, N-methylethanolamine, N-ethylethanolamine, triisopropanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, mono Methyltripropylammonium hydroxide, (2-hydroxyethyl) tripropylammonium hydroxide, and (1-hydroxypropyl) trimethylammonium hydroxide, characterized in that one or two or more kinds selected from the group consisting of The composition for photoresist peeling which is used. The method of claim 1, wherein the water-soluble polar solvent compound is N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc) , Dimethylformamide (DMF), tetrahydrofurfuryl alcohol, isophorone, diethyl adipate, dimethylglutarate, sulfolane, and gamma-butyllactone (GBL) It is a mixture, The composition for peeling photoresist characterized by the above-mentioned. The method of claim 1, wherein the alkylene glycol alkyl ether compounds are ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol Monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate. Photoresist stripping composition. The composition of claim 1, wherein the α-hydroxycarboxylic acid is one or a mixture of two or more selected from the group consisting of glycolic acid, lactic acid, α-hydroxyisolactic acid, and tartaric acid. . The method according to claim 1, wherein the aromatic compound containing a hydroxyl group is one or a mixture of two or more selected from the group consisting of hydroquinone, catechol, resorcinol, pyrogallol, methyl calate, and gallic acid A composition for peeling photoresist, characterized in that. The method according to claim 1, wherein the sulfur-containing anticorrosive agent containing a mercapto group is one or a mixture of two or more selected from the group consisting of ammonium thiosulfate, thioglycerol, thioglycolic acid, thioacetic acid, and thiosalicylic acid. The composition for photoresist peeling which is used. The composition of claim 2, wherein the linear polyhydric alcohol compound is one or a mixture of two or more selected from the group consisting of sorbitol, xylitol, mannitol, and threazole. A method of removing the photoresist by depositing, spraying, or depositing and spraying for 30 seconds to 40 minutes at a temperature of 10 to 100 ° C using the composition for peeling photoresist according to any one of claims 1 to 10.