KR19990007139A - Photoresist Peeling Composition - Google Patents

Abstract

Provided is a photoresist peeling composition capable of peeling a resist modified material and sidewall protective film formed during etching at a low temperature for a short time without causing corrosion of conductive films such as aluminum and copper at all. This peeling composition can be effectively used for peeling resists and removing sidewall protective films used for forming microcircuits of semiconductor devices such as liquid crystal panel devices and LSIs. The photoresist peeling composition of the present invention preferably has a composition of the following (a) or (b).

(a) Photoresist comprising 5 to 90% by weight of aprotic polar solvent, 1 to 70% by weight of water, 0.01 to 20% by weight of fluoride, and 0.01 to 20% by weight of quaternary ammonium salts or hydroxylamines. Peeling composition.

(b) 5 to 90% by weight of an aprotic polar solvent, 1 to 70% by weight of water, 1 to 90% by weight of amino alcohol, and an anticorrosive agent comprising ethylenediaminetetraacetic acid or a salt thereof. A composition for peeling photoresist consisting of 0.01 to 40% by weight.

Description

Photoresist Peeling Composition

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoresist stripping composition, and more particularly, to a photoresist stripping composition which is used in the manufacture of semiconductor devices such as liquid crystal panel devices and LSIs, and has less conductive metal film corrosion.

In the manufacture of a semiconductor device such as a liquid crystal panel device or an LSI, a conductive metal film is formed on a substrate, an insulating film such as a SiO ₂ film is formed, and then an insulating film of the non-mask portion is not formed using a photoresist. After etching to form the microcircuit, the removal of the insignificant photoresist layer with the stripping liquid is performed.

Conventionally, various preferable organic or inorganic chemicals have been found and used so far for peeling such photoresist. For example, practically in Japanese Unexamined Patent Publication No. 64-81950, a release agent composed of dimethyl sulfoxide (hereinafter referred to as DMSO) and amino alcohols has been proposed as an organic release agent. In addition, Japanese Patent Application Laid-Open No. 4-350660 proposes a release agent composed of 1,3-dimethyl-2-imidazolicinone and DMSO. Alternatively, Japanese Patent Application Laid-Open No. 7-271056 proposes a release agent composed of an organic ammonium carboxylate salt, a fluorine compound, and DMSO.

In recent years, high density photoresists for forming fine patterns have been used due to the higher density of integrated circuits. In addition, the etching method is a dry etching method using a halogen gas instead of the conventional chemical etching method using an organic solvent or the like. Furthermore, in addition to the dry etching method, processing such as ashing, ion implantation, and the like are performed.

In such dry etching, incineration, ion implantation, and the like, the photoresist film is changed from an organic film to a film exhibiting inorganic properties. Further, by dry etching, a sidewall protective film made of a reactive film or a deposition film made of halogen gas and aluminum wiring is attached to the side surface of the fine pattern. These photoresist denatured substances and deposits such as sidewall protective films cannot be sufficiently peeled off from ordinary peeling liquids composed of DMSO and amino alcohols, but a treatment is required at a high temperature such as 80 to 130 ° C. . Moreover, when amino alcohols are used, after peeling process, a problem arises that it wash | cleans with water and aluminum wiring corrodes in trace amount of amino alcohols. Moreover, when a fluorine compound is used, the problem that a silicon oxide part corrodes under processing conditions arises.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to resist-detach a conductive film such as aluminum or copper, and to remove the resist modified material and the sidewall protective film which are formed at the time of etching at a low temperature for a short time. To provide.

In the present invention to achieve the above object, the form of the photoresist stripping composition of the present invention is characterized in that consisting of an aprotic polar solvent, water, fluoride and quaternary ammonium salt or hydroxylamine, preferably These ratios are 5 to 90% by weight of the aprotic polar solvent, 1 to 70% by weight of water, 0.01 to 20% by weight of fluoride, and 0.01 to 20% by weight of quaternary ammonium salts or hydroxylamines. will be.

In addition, another embodiment of the photoresist stripping composition of the present invention is characterized by consisting of an aprotic polar solvent, water, an amino alcohol, and an anticorrosive agent comprising an ethylenediaminetetraacetic acid (EDTA) or a salt thereof. Preferably, the proportion thereof is 5 to 90% by weight of the aprotic polar solvent, 1 to 70% by weight of water, 1 to 90% by weight of amino alcohol, but ethylenediaminotetraacetic acid or a salt thereof is essential. It consists of 0.01-40 weight%.

In the present invention, the following preferred embodiments are included.

a. The aprotic polar solvent is dimethyl sulfoxide, N-methyl-2-pyrrolidone, γ-butyrolactone or propylene carbonate.

b. Wherein said water is rectified or ion-exchanged water.

c. The fluoride is ammonium fluoride or ammonium hydrogen fluoride.

d. The quaternary ammonium salt is tetramethylammonium hydroxide or tetramethylammonium hydroxide pentahydrate.

e. The amino alcohol is ethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, 2-aminoethoxyethanol, 2- (2-aminoethylamino) ethanol, N-methylethanolamine or 2-diethylaminoethanol .

f. The anticorrosive may also be hydroxylamine, N, N-dimethylhydroxylamine, N, N-diethylhydroxylamine, tetramethylammonium hydroxide, tetramethylammonium hydroxide pentoxide, citric acid, ammonium citrate, citric acid Containing ammonium hydrogen, pyrocaticol, pyrrogalol, methylcatecool, Ptbutylcatalcohol, hydroquinone monomethylether, protocatechuic acid or phloroglucinol.

The aprotic polar solvent used in the present invention is not particularly limited, but is preferably water-soluble in order to be excellent in affinity with the photoresist or to facilitate the washing process of the washing liquid after removing the sidewall protective film. In particular, it is preferable that the positive photoresist be easily dissolved and a good solvent of the inorganic salt. As such an aprotic polar solvent, for example, dimethyl sulfoxide (DMSO), N, N-dimentylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone Glycols such as (NMP), N, N-dimethylsulfoamide, γ-butyrolactone, propylene carbonate, 1,3-dimethyl-2-imidazolincinone, N-aceto-ε-caprolactam, triethylene glycol Glycol acetates, such as 3-methoxy-3-methyl-1-butanol, and propylene glycol-1-monomethyl acetate, although dimethyl sulfoxide and N-methyl are preferred solvents for photoresists. 2-pyrrolidone, γ-butyrolactone, and propylene carbonate are particularly preferably used. In addition, in the practice of the present invention, these aprotic polar solvents may be used in one kind, but two or more kinds can be used in combination.

Among the components of the photoresist stripping composition, the composition ratio of such aprotic polar solvent is preferably 5 to 90% by weight, more preferably 40 to 90% by weight, still more preferably 50 to 90% by weight. . When the amount of the aprotic polar solvent is small, the photoresist peeling property is low. On the contrary, when the amount of the aprotic polar solvent is too large, the sidewall protective film cannot be sufficiently removed. For example, the solubility of the fluoride in the composition is reduced. It shows a tendency that a stable stripping solution with a fluoride amount that can be sufficiently removed can be obtained.

As the water used in the present invention, purified water such as rectified water and ion-exchanged water is preferably used. In addition, the water component is an important component because it dissolves fluoride and the like, which is another component of the photoresist stripping composition of the present invention, to form a uniform and stable resist stripping solution.

The composition ratio of water in the component of the photoresist peeling composition is preferably 1 to 70% by weight, more preferably 2 to 50% by weight, still more preferably 5 to 50% by weight. When the amount of water is small, the solubility of the fluoride decreases so that a stable stripping solution of a fluoride amount can be obtained in which the sidewall protective film can be adequately removed. On the contrary, when the amount of water is too large, the photoresist stripping property becomes low. Indicates a tendency.

The form of the photoresist stripping composition of the present invention is characterized in that the aprotic polar solvent and water are blended with fluoride, quaternary ammonium salt or hydroxylamine.

The fluoride used for this is preferably a good solvent of silicon oxide such as SiO _2. Specifically, ammonium fluoride (FA) and ammonium bifluoride (FHA), potassium fluoride (KF), ammonium fluoride and antimony fluoride, etc. Although FA and FHA are used preferably. In addition, in the practice of the present invention, two or more kinds of these fluorides can be used in combination.

In the component of the photoresist peeling composition, the composition ratio of the fluoride is preferably 0.01 to 20% by weight, more preferably 0.05 to 15% by weight. If the amount of fluoride is small, the sidewall protective film cannot be sufficiently removed, and if the amount of the fluoride is too large, the sidewall protective film is excessively removed to narrow the working width, and the SiO ₂ film of the substrate element tends to be eroded.

The quaternary ammonium salt preferably dissolves the positive photoresist easily, and specifically, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide pentahydrate, tetraethylammonium hydroxide, tetrapropylammonium Hydroxide, trimethylethylammonium hydroxide, dimethyldiethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide, triethyl (2-hydroxyethyl) ammonium hydroxide, quaternary ammonium carbonate , Quaternary ammonium bicarbonate, quaternary ammonium acid salt, quaternary ammonium acetate, and quaternary ammonium hydrate. In the present invention, tetramethylammonium hydroxide (TMAH), tetramethyl as a universal quaternary ammonium salt. Ammonium hydroxide pentahydrate is preferably used. In addition, in the practice of the present invention, these quaternary ammonium salts may be used in one kind, but two or more kinds can be used in combination.

Furthermore, in the present invention, in place of the quaternary ammonium salt or in combination with the quaternary ammonium salt, hydroxylamine or hydroxylamine salt, hydrazine, hydrazine hydrate or hydrazine salt and the like can be used, and hydroxylamines are particularly preferable. Is used.

The composition ratio of the quaternary ammonium salt or / and hydroxylamine is preferably 0.01 to 20% by weight, more preferably 0.05 to 10% by weight in the components of the photoresist peeling composition. If the amount of quaternary ammonium salt or hydroxylamine is small, the resist residue or sidewall protective film cannot be removed properly. On the contrary, if the amount of quaternary ammonium salt or hydroxylamine is too large, such as aluminum of the substrate element. The conductive film is likely to corrode.

In another embodiment of the photoresist stripping composition of the present invention, an aprotic polar solvent and water are further formulated with an anti-corrosive agent comprising amino alcohol, ethylenediaminetetraacetic acid (EDTA) or a salt thereof. It is characterized by.

It is preferable that the amino alcohol used for these easily dissolves the positive photoresist, and specifically, ethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, 2-aminoethoxyethanol, 2- (2 -Aminoethylamino) ethanol, N-methylethanolamine, 2-diethylaminoethanol, t-butyldiethanolaminoisopropanolamine, 2-amino-propanol, 3-amino-1-propanol, isobutanolamine and 2-amino Although (2-ethoxy) propanol etc. can be mentioned, In this invention, ethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, 2-aminoethoxyethanol, 2- (2-aminoethylamino) ethanol which are versatile in this invention are mentioned. , N-methylethanolamine or 2-diethylaminoethanol is preferable, and ethanolamine is particularly preferably used from the viewpoint of cost. In addition, in the present invention, these amino alcohols may be used alone, but two or more kinds thereof may be used in combination.

The composition ratio of aminoalcohol in the component of the photoresist peeling composition is preferably 1 to 90% by weight, more preferably 3 to 80% by weight. If the amount of the amino alcohol is small, the sidewall protective film cannot be sufficiently removed, and the type of the anticorrosive agent tends to deteriorate the solution stability. On the contrary, if the amount of the amino alcohol is too high, the sidewall protective film is excessively removed and the working width is increased. It becomes narrower and also tends to corrode the aluminium wiring.

In the composition for photoresist peeling of the present invention, another anticorrosive agent of the above components is blended. As an anticorrosive agent, the anticorrosive agent which contains ethylenediamino tetraacetic acid (EDTA) or its salt as an essential component is used preferably. EDTA is particularly preferred because it is not ionically contaminating or active. Examples of the salt of EDTA include ammonium salts and alkali metal salts such as sodium and potassium, but ammonium salts are preferred because they do not have ion contamination or sublimation properties.

The composition ratio of the anticorrosive agent which makes ethylenediamine tetraacetic acid or its salt essential in the component of the photoresist peeling composition becomes like this. Preferably it is 0.01-40 weight%, More preferably, it is 0.05-30 weight%. A small amount of anticorrosive agent tends to corrode the aluminium wiring, and conversely, when the amount of the anticorrosive agent is too large, the removal of resist residues or sidewall protective films may not be sufficient.

In this invention, in addition to this EDTA and its salt, another anticorrosive agent can be used together. Other anticorrosive agents include hydroxylamine, N, N-dimethylhydroxylamine, N, N-diethylhydroxylamine, tetramethylammonium hydroxide, tetramethylammonium hydroxide pentahydrate, citric acid, ammonium citrate, hydrogen citrate Ammonium, pyrocaticol, pyrrogalol, Pt butylcatolol, methylcatolol, hydroquinone monomethylether, protocatechuic acid and phloroglucinol, and the like, but in the present invention, hydroxylamine, N, N-di Ethylhydroxylamine, teramethylammonium hydroxide, ammonium hydrogen citrate, pyrocaticol, hydrokinone monomethyl ether, protocatechuic acid and fluoroglucinol are preferably used. In using these anticorrosive agents, while improving the anticorrosive property with respect to a conductive film, the peelability of a sidewall protective film can be made favorable.

In the composition for photoresist stripping of the present invention, other components other than the components described above can be appropriately added and used within a range that does not interfere with the effects of the present invention. For example, to lower the surface tension or to prevent repositioning of the resist as an element, for example, anionic surfactants such as alkylbenzene lactates and nonionic interfaces such as polyoxyethylene ethers of alkylphenols. Surfactant, such as active agent, amphoteric surfactant, such as dodecyldiaminoethylglycine hydrochloride, and cationic surfactant, such as alkyldimethylbenzyl ammonium chloride, can be added.

Furthermore, in the present invention, it is possible to add a stripping liquid aid such as hydroxyl, succinic acid, catholic acid, pyrrogalol or sodium pyrroline to block metal ions, which alleviate the corrosive action of the metal.

Photoresists in which the photoresist stripping composition of the present invention is suitably used include a positive resist, a negative resist, and a positive / negative both-type resist, and particularly, a photoresist composed of a novolak-based phenol resin and a naphthoquinone diazide effectively Used.

In addition, as the dry etching gas used in the present invention, any of salts of halogen gas, hydrogen bromide, and boron trichloride, and also contains gases such as carbon tetrafluoride, boron trifluoride, hydrogen chloride, carbon trichloride, and silicon tetrachloride. Can also be used for systems.

Using the photoresist stripping composition (peel solution) of the present invention, as a removal treatment condition of the resist residue and sidewall protective film remaining after the painting, high temperature peeling such as 80 ° C. or higher is not required, and the treatment at a lower temperature is possible. . That is, although the peeling process is possible at 80 degreeC or more by using the peeling liquid of this invention, there exists a tendency for the composition of a peeling liquid to change easily. In the present invention, the resist can be removed at a relatively low temperature of less than 80 ° C, for example, 40 ° C to 78 ° C, more preferably about 50 ° C to 70 ° C.

The photoresist stripping composition of the present invention can be effectively used for peeling resists and removing sidewall protective films used for forming microcircuits in semiconductor devices such as liquid crystal panel devices and LSIs.

EXAMPLE

(Examples 1 to 8 and Comparative Examples 1 to 5)

Positive photoresist THMR-iP2000 (manufactured by Tokyo Oka Kogyo Co., Ltd.) on an Al-Si-Cu film having a thickness of about 1 μm, and a Si substrate having SiO ₁ having a thickness of about 1 μm sequentially deposited thereon. After the coating was applied so as to have a thickness of 2 m, the mask was exposed and developed to form a mask of a positive photoresist.

Next, remove the SiO ₂ mask material in the non-mask area by dry etching, and further, remove a large portion of the photoresist by incineration, and then isolate the substrate at 70 ° C. for 20 minutes with the photoresist stripping composition shown in Table 1 below. After rinsing in distilled water, the corrosion state of the resist residue, sidewall protective film and Al-Si-Cu film on the substrate was observed and evaluated by SEM (scanning electron microscope) photograph. The judgment of SEM observation is as follows. The results are shown in Table 1.

○…. The resist residue and the sidewall protective film residue were not recognized at all.

Δ. The resist residue and the sidewall protective film residue were hardly recognized.

×… The resist residue and the sidewall protective film residue cannot be removed at all.

G… No corrosion of Al-Si-Cu film.

p… Corrosion of Al-Si-Cu film.

Example Stripping solution composition (weight ratio) Resist and sidewall protective residue Al-Si-Cu Corrosion Example 1 DMSO / water / FA / TMAH = 80/20/1 / 0.02 △ G Example 2 DMSO / water / FA / TMAH = 80/20/1/1 ○ G Example 3 DMSO / water / FA / TMAH = 80/40/1/1 △ G Example 4 DMF / Water / FA / TMAH = 80/20/1/1 △ G Example 5 DMAc / Water / FA / TMAH = 80/20/1/1 ○ G Example 6 NMP / water / FA / TMAH = 80/20/1/1 ○ G Example 7 NMP / water / FHA / TMAH = 80/20/1/1 ○ G Example 8 NMP / water / FHA / HA = 80/20/1/1 ○ G Comparative Example 1 DMSO / water / FA = 80/20 / 0.02 × P Comparative Example 2 DMSO / water / FA = 80/20/1 × G Comparative Example 3 DMSO / MEA = 70/30 × P Comparative Example 4 DMSO / MEA / Water = 60/20/20 × P Comparative Example 5 DMSO / MEA / Water / FA = 60/20/20/1 △ P

DMSO Co., Ltd .: Dimethyl sulfoxide

FA: ammonium fluoride

TMAH: tetramethylammonium hydroxide

DMAc: Dimethylacetamide

NMP: N-methyl-2-pyrrolidone

HA: hydroxylamine

DMF: Dimethylformamide

MEA: monoethanolamine

FHA: Ammonium Hydrogen Fluoride

(Examples 9 to 21 and Comparative Examples 6 to 7)

A positive photoresist THMR-iP3600 (manufactured by Tokyo Oka Kogyo Co., Ltd.) was 2 μm thick on an Al-Si-Cu film having a thickness of about 1 μm, and a Si substrate on which SiO ₂ having a thickness of about 1 μm was sequentially deposited thereon. After application | coating so that it may become, it exposes in a mask, and develops, and forms it as the mask of a positive photoresist.

Next, after removing the SiO ₂ mask material in the non-mask area by dry etching, and further removing a large portion of the photoresist by incineration, they were treated with the photoresist peeling composition shown in Table 1 at 70 ° C. for 20 minutes, respectively. After rinsing in distilled water, the corrosion residues of the resist residue, sidewall protective film, and Al-Si-Cu film on the substrate were observed and evaluated by scanning electron microscope (SEM) photograph. The judgment of SEM observation is as follows. The results are shown in Table 2.

○…. The resist residue and the sidewall protective film residue were not recognized at all.

No corrosion of Al-Si-Cu film

No corrosion of SiO ₂

Δ. The resist residue and the sidewall protective film residue were hardly recognized.

A slight corrosion of the Al-Si-Cu film was noticed.

×… The resist residue and the sidewall protective film residue cannot be removed at all.

Corrosion of Al-Si-Cu film

Corrosion of SiO ₂

Example Stripping solution composition (weight ratio) A B C 9 DMSO / MEA / Water / EDTA = 30/50/20/4 ○ △ ○ 10 DMSO / MEA / Water / EDTA = 40/40/20/4 ○ ○ ○ 11 DMSO / MEA / Water / EDTA = 60/20/20/4 △ ○ ○ 12 DMSO / MEA / Water / EDTA = 40/40/20/1 ○ △ ○ 13 DMSO / MEA / Water / EDTA = 30/50/20 / 0.5 △ △ ○ 14 DMSO / MEA / Water / EDTA = 70/20/10/4 △ ○ ○ 15 DMSO / MEA / Water / EDTA = 50/20/30/4 ○ △ ○ 16 DMSO / MEA / water / EDTA / pyrocaticol = 60/20/20/4/4 ○ ○ ○ 17 DMSO / MEA / Water / EDTA / HA = 30/50/20/4/10 ○ ○ ○ 18 NMP / MEA / water / EDTA / pyrocaticol = 60/20/20/4/4 ○ ○ ○ 19 DMSO / MEA / Water / EDTA = 40/40/20/4 △ ○ ○ 20 DMSO / MIPA / Water / EDTA = 40/40/20/4 ○ ○ ○ 21 DMSO / 2-AEE / water / EDTA = 40/40/20/4 ○ ○ ○ Comparative example Stripping solution composition (weight ratio) A B C 6 DMSO / MEA / Water = 60/30/10 × × ○ 7 DMSO / MEA / Water / FA = 60/30/10/1 ○ × ×

A: resist residue, sidewall protective film residue

B: Corrosion of Al-Si-Cu

C: Corrosion of SiO ₂

DMSO: Dimethylsulfoxide MEA: Monoethanolamine

EDTA: ethylenediaminotetraacetic acid HA: hydroxylamine

NMP: N-methyl-2-pyrrolidone DEA: diethanolamine

MIPA: monoisopropanolamine FA: ammonium fluoride

2-AEE: 2-aminoethoxyethanol

The resist stripping composition of the present invention is capable of satisfactorily peeling off resist residues and sidewall protective films after trietching and incineration, which are difficult to remove conventionally, and further, do not corrode substrates such as Al, Al-Si-Cu and Cu, which are easily corroded. It does not work.

In addition, the peeling treatment temperature conditions of the present invention, when the temperature is lower than the conventional temperature, there is no industrial damage because there is no damage such as corroding other members required to improve the productivity.

In the peeling composition which used together EDTA or ammonium salt of this invention, a side wall protective film can be peeled further more effectively, without especially corroding electrically conductive films, such as aluminum and copper.

Claims (11)

A photoresist stripping composition comprising an aprotic polar solvent, water, a fluoride and a quaternary ammonium salt or hydroxylamines. A photoresist stripping composition comprising an antiprotic polar solvent, water, an amino alcohol, and an anticorrosive agent comprising an ethylenediaminetetraacetic acid or a salt thereof. The photoresist stripping composition according to claim 1 or 2, wherein the aprotic polar solvent contains 5 to 90% by weight and water is 1 to 70% by weight. The photoresist stripping composition according to claim 1 or 2, wherein the aprotic polar solvent is dimethyl sulfoxide, N-methyl-2-pyrrolidone, γ-butyrolactone or propylene carbonate. The composition of claim 1 or 2, wherein the water is rectified water or ion-exchanged water. The composition of claim 1, wherein the fluoride is ammonium fluoride or ammonium hydrogen fluoride. The composition of claim 1, wherein the quaternary ammonium salt is tetramethylammonium hydroxide or tetramethylammonium hydroxide pentahydrate. The composition of claim 1 or 3, wherein 0.01 to 20% by weight of the fluoride, 0.01 to 20% by weight of quaternary ammonium salt or hydroxylamine are contained. The method of claim 2, wherein the amino alcohol is ethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, 2-aminoethoxyethanol, 2- (2-aminoethylamino) ethanol, N-methylethanolamine or 2- It is diethylamino ethanol, The composition for photoresist peeling characterized by the above-mentioned. The method according to claim 2, wherein the anticorrosive is furthermore hydroxylamine, N, N-dimethylhydroxylamine, N, N-diethylhydroxylamine, tetramethylammonium hydroxide, tetramethylammonium hydroxide pentahydrate, citric acid For photoresist stripping, comprising ammonium citrate, ammonium hydrogen citrate, pyrocaticol, pyrrogalol, methylcatolol, Ptbutylcatolol, hydroquinone monomethylether, protocatechuic acid, or fluoroglucinol Composition. The composition for peeling photoresist according to claim 2 or 3, wherein the amino alcohol contains 1 to 90% by weight, and an anticorrosive agent comprising ethylenediaminetetraacetic acid or a salt thereof in an amount of 0.01 to 40% by weight. .