KR20030002940A - Resist removing composition and resist removing method using the same - Google Patents

Abstract

PURPOSE: Provided are a composition for removing resist, which has excellent ability for removing the resist, polymers, organic metallic polymers, and metal oxides and dose not cause damage to a lower part membrane and dose not leave residues after rinsing, and a method for removing the resist by using the composition. CONSTITUTION: The composition for removing the resist contains: alkoxy N-hydroxyalkyl alkanamide represented by the formula 1: R4-O-R3-CO-N-R1R2OH; at least one compound selected from the group consisting of an alkanol amine represented by the formula 2: R1-NH-R2OH, a polar material having a dipole moment of more than 3, and an attack inhibitor represented by the formula 3: R6-(OH)n; hydroxy ammonium salt like hydroxy ammonium sulfate. And the method for removing the resist contains the steps of: forming a resist membrane on a substrate; bring the substrate into contact with the composition for removing the resist. In the formula, R1 is H, C1-C5 hydrocarbon, or aromatic hydrocarbon having 1-3 ring structure, R2 is C1-C5 hydrocarbon or aromatic hydrocarbon having 1-3 ring structure, each of R3 and R4 is C1-C5 hydrocarbon, R6 is C1-C5 hydrocarbon, C1-C5 hydrocarbon having -COOH, aromatic hydrocarbon having 1-3 ring structure, or aromatic hydrocarbon having -COOH and 1-3 ring structure, and n is an integer of 1-4.

Description

Resist removing composition and resist removing method using the same

The present invention relates to a resist removing composition and a resist removing method using the same.

In order to complete an integrated circuit, various wiring patterns (eg, tungsten, aluminum, copper or titanium titanium nitride wiring, etc.) and contact or via holes exposing the wiring patterns must be formed on the substrate. The process of forming the wiring pattern and the contact hole or the via hole includes a photo process, an etch process, a resist removing process, a rinse process, and a dry process.

The main issue of the resist removal process is to completely remove resist and etch residues from the substrate surface as quickly as possible without damaging the underlying film. Generally, the resist removal process is a combination of a dry strip process such as an ashing process and a wet strip process using an organic stripper. In the wet strip process, the surface of the integrated circuit board is free of impurities such as residues generated during the ashing process and the etching process for forming the wiring pattern or contact hole (via hole) and residues in the ashing process. Remove from Residues to be removed include organic polymers formed by reacting plasma with components such as C, H, and O, which form a resist pattern during the plasma etching or reactive ion etching (RIE) process, and the wiring during the etching or ashing process. Insulators or metallic oxides formed by back-sputtering an organic metallic polymer formed by back-sputtering a material into a resist pattern and a sidewall of a contact hole or via hole and an insulating film under the wiring pattern. There is this.

To date, the main component is a basic amine reducing agent such as hydroxyamine, diglycolamine, monoethanolamine or methylethanolamine, polar solvent such as water, and the like. Organic strippers composed of organic acids such as solvents and catechol are widely used.

However, since the basic amine constituting the organic stripper has a relatively low reducing power, it does not completely remove etching residues (metal oxides or organometallic polymers) generated during the formation of wirings or contact holes. Therefore, a step of treating nitric acid solution is required as a pre-ashing step before the ashing process.

In addition, the conventional organic stripper is mainly composed of organic components and the like and high in viscosity, when rinsed only with deionized water, it is not completely removed and tends to remain on the substrate to act as organic contamination or to leave residue.

In addition, water, which is a polar solvent of the organic stripper, can easily corrode the underlying film exposed to the stripper, especially the wiring film, thereby modifying the profile of the wiring pattern. Therefore, a rinsing process using an alcohol-based rinsing agent such as isopropyl alcohol (hereinafter referred to as IPA) should be further performed.

Therefore, the nitric acid treatment step should be performed as an ashing pretreatment step to enhance the removal ability of polymers, or the IPA rinse step should be performed before the deionized water rinse step to prevent corrosion of the wiring film. It is a factor that lowers productivity. In addition, since the pretreatment material (nitric acid) and aftertreatment material (isopropyl alcohol) must be consumed in addition to the resist remover, the production cost increases. In addition, the volume of the resist removal apparatus becomes unnecessarily large because each bath for pretreatment and posttreatment is required.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide a resist removing composition having excellent properties of removing resists, polymers, organometallic polymers, and metal oxides, not causing damage to the underlying film, and having no residue after rinsing. .

Another object of the present invention is to provide a method for removing a resist using the resist removing composition.

1 is a flowchart illustrating a resist removing step according to the present invention, in which a dotted line indicates a step that is omitted when using the resist removing composition according to the present invention as a conventional resist removing step.

The resist removal composition according to the present invention for achieving the above technical problem is an alkoxy N-hydroxyalkyl alkanamide; At least one compound selected from the group consisting of alkanol amines, polar substances having a dipole moment of at least 3 and damage inhibitors; And hydroxyammonium salts.

According to a resist removing method for achieving another technical problem, first, after providing a substrate on which a resist is formed, the substrate is contacted with the resist removing composition to remove the resist from the substrate.

The resist removing composition according to the present invention is not only excellent in resist removing ability, but also effectively removing polymers, organometallic polymers, and metal oxides. It also has the property of leaving no residue and residue after rinsing without damaging the underlying film exposed to the composition.

Hereinafter, the resist removing composition and the resist removing method using the same according to the present invention will be described in detail. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. It is provided for complete information.

The resist removing composition according to the present invention includes alkoxy N-hydroxyalkyl alkanamide; At least one compound selected from the group consisting of alkanol amines, polar substances having a dipole moment of at least 3 and damage inhibitors; And hydroxyammonium salts.

Alkoxy N-hydroxyalkyl alkanamides are represented by the following formula (1).

R ₄ -OR ₃ -CO-NR ₁ R ₂ OH

Wherein R ₁ is H atom, C 1 -C 5 hydrocarbon or aromatic hydrocarbon having 1-3 ring structure; R ₂ is an aromatic hydrocarbon having 1 to 5 carbon atoms or 1 to 3 ring structures; R ₃ and R ₄ each represent a hydrocarbon having 1 to 5 carbon atoms.

Most preferably in the above formula, R ₁ is H atom, R ₂ is -CH ₂ CH _2- , R ₃ is -CH ₂ CH ₂ -and R ₄ is -CH ₃ .

Alkanol amines are compounds represented by the following formula (2).

NH-R ₁ -R ₂ OH

In the above formula, R ₁ represents an H atom, a hydrocarbon having 1 to 5 carbon atoms or an aromatic hydrocarbon having 1 to 3 ring structures, and R ₂ represents an aromatic hydrocarbon having 1 to 5 hydrocarbons or 1 to 3 ring structures. .

Monoethanolamines in which R ₁ is H and R ₂ is -CH ₂ CH ₂ -are suitable as alkanolamines of the present invention.

As a polar material having a dipole moment of 3 or more, water, methanol or dimethyl sulfoxide may be used.

The damage inhibitor is represented by the following formula (3).

R _6- (OH) _n

In the above formula, R ₆ is a hydrocarbon having 1 to 5 carbon atoms, a hydrocarbon having 1 to 5 carbon atoms bonded to a -COOH group, an aromatic hydrocarbon having 1 to 3 ring structures, or 1 to 1 bonded to a -COOH group An aromatic hydrocarbon having three ring structures, n is an integer and represents 1-4.

In particular, catechol in which R ₆ is a benzene ring and n is 2 is preferable as a damage preventing agent. In addition, gallic acid (gallic acid) which is a damage preventing agent well known in the prior art can also be used.

As the hydroxyammonium salt, hydroxyammonium sulfate is suitable.

The mechanism of action of the resist removal composition according to the present invention is as follows.

Alkoxy N-hydroxyalkyl alkanamides include hydroxy (-OH) groups, alkoxy groups (-OR ₄ ) and carbonyl groups (C═O). Therefore, it is very effective for exfoliation and dissolution of resist and polymer.

In addition, it reacts with an organometallic polymer or the like as in Scheme 1 below to easily remove the organometallic polymer from the substrate surface.

※ Mp stands for organometallic polymer.

Alkanol amines are also effective for the removal of polymers or organometallic polymers. The mechanism of action of the alkanol amine is shown in Scheme 2 below by taking monoalkanolamine as an example.

Polar materials with dipole moments of 3 or more exhibit high solubility in cross-linked polymers and resists. That is, the polymer that is strongly bonded to the sidewalls of the resist pattern and the exposed lower layer surface can be effectively removed, and the resist can also be easily removed.

On the other hand, the damage preventing agent not only functions as a dissolving agent for the organometallic polymer but also serves to prevent corrosion or damage of the wiring exposed on the surface of the integrated circuit board. In most cases, a metal oxide film is formed on the surface of the wiring pattern exposed on the surface of the integrated circuit board. When these metallic oxide films react with the reducing agent to be converted into metal ions, the damage inhibitor chelates with the metal ions to form a chelate compound. As a result, the surface of the exposed metal wiring pattern is covered with a stable chelating compound, thereby effectively preventing corrosion or damage to the wiring pattern. The mechanism by which the damage preventing agent prevents damage to the metal film is described by using catechol as an example.

※ M represents metal

The hydroxyammonium salt also improves the removal ability of the polymer and makes the viscosity of the resist removal composition easy to remove with deionized water.

Therefore, the resist removing composition according to the present invention is not only excellent in resist removing ability, but also effectively removes polymers, organometallic polymers, and metal oxides. Moreover, it does not damage the lower film exposed to a composition, has a viscosity suitable for rinsing with deionized water, and does not leave a residue and an organic residual film.

Representative compositions for removing the resist according to the present invention and the weight percent of each component are shown in Table 1 below.

Resist Removal Composition Alkoxy Nhydroxyalkylalkanamides (wt%) Alkanolamine (% by weight) Polar material (% by weight) Damage prevention agent (% by weight) Hydroxyammonium salt (% by weight) One 30-99.9 0.01-69.99 0.01-30 2 30-99.9 0.01-69.99 0.01-30 3 30-99.9 0.01-69.99 0.01-30 4 30-99.9 0.01-30 0.01-30 0.01-30 5 30-99.9 0.01-30 0.01-30 0.01-30 6 30-99.9 0.01-30 0.01-30 0.01-30 7 30-99.9 0.01-30 0.01-30 0.01-30 0.01-30

The content range of the above-described compositions can effectively remove the resist and the polymer, minimize the damage to the underlying film exposed to the resist removal composition, such as wiring, and have a viscosity that can be rinsed with deionized water. To show the optimal range.

Among the above-mentioned compositions, composition 7 has the most excellent resist and polymer removal ability, and if there is a metal film as the resist under film, it does not cause damage to the metal film and is completely removed with deionized water to leave residues and residues. . In addition, when the amine is included together with the amide, such as compositions 1, 4, 5, and 7, the resist and polymer removal ability are further improved.

On the other hand, the compositions (1, 2, 4) that do not contain a damage preventing agent may also have the same effect as the composition of 7 when the material damaged by the composition such as wiring is not exposed to the resist removing composition. In addition, compositions (1, 3, 5) which do not contain polar substances with dipole moments of 3 or more are used when the prevention of damage to the metal film is a more important factor, or when the amount of polymer to be removed is very small or the polymer removal pretreatment When the process is carried out, the same effects as in the composition of 7 can be obtained.

As described above, the resist removal compositions according to the present invention not only have excellent resist removal ability, but also can easily remove polymers, organometallic polymers, and metal oxides, which are etching byproducts. In addition, the underlying film exposed to the resist removing composition, such as wiring, is not damaged. Then, it is completely removed with deionized water and does not remain on the substrate. In addition, the materials have the advantage of being composed of a lower cost compound than the materials constituting the conventional resist removal compositions.

How to remove resist

The step of removing the resist using the resist removing composition according to the present invention will be described with reference to FIG.

First, a resist pattern is formed through a photo process (100). Subsequently, various processes for completing a semiconductor device using a resist pattern as a mask, for example, an etching (dry or wet) process or an ion implantation process may be performed (110). Subsequently, ashing, which is a dry strip process, is performed on the substrate on which the resist pattern is formed (120). Next, a wet strip process is performed to remove the resist, the polymer and the organometallic polymers by contacting the resist removing composition shown in Table 1 (130). In the method of contacting with the resist removal composition, the resist removal composition is immersed in a bath, and the substrate is contacted by immersing the substrate therein or by spraying the resist removal composition onto the substrate.

When using the resist removal composition according to the present invention, the resist removal step may be carried out at a low temperature of 70 ℃ or less. In particular, it is possible to carry out at a temperature of room temperature to 70 ℃, preferably 45 ℃ to 70 ℃. And 10 to 30 minutes are suitable for a contact time.

The resist that can be removed by the resist removing composition of the present invention is not only used for conventional i-line (365 nm) resists and KrF excimer laser (248 nm) resists, but also for ArF excimer laser (193 nm) resists for short wavelength exposure sources. Applicable.

When the resist removal is completed, a step of rinsing the resist removing composition and the dissolved resist remaining on the substrate surface is performed (140). Rinse with deionized water and can be carried out in two stages as needed. Finally, the substrate is dried by a spin dry method or a dry method using isopropyl alcohol to remove deionized water remaining on the surface of the substrate (150).

The substrate completed by the drying step 150 is transferred to the next process. When the resist is used again in a subsequent process, after the desired process is completed, the used resist is removed again through the process of FIG. The semiconductor device is completed through the repeating unit process and resist removal process.

As can be seen in Figure 1, the resist removal composition according to the present invention is excellent in the removal power of the polymer, organometallic polymer and metal oxide as well as the resist removal power. Therefore, it is suitable for a process of generating by-products which are not easily removed by the conventional organic stripper, and, unlike the conventional method, the resist removal pretreatment step 115 is not required. In addition, since the damage to the resist underlayer is prevented and no residue and organic residual film are left, the resist removal post-processing step 135 can also be omitted. Therefore, it is possible to completely remove the resist in a very simplified process compared to the conventional removal process, and in the resist removal apparatus, since the bath or the like necessary for the resist removal pretreatment step 115 and the post-treatment step 135 is not required, The removal device is simplified. In addition, there is no need to use materials used in the pretreatment and posttreatment steps, such as nitric acid and IPA, which can significantly improve the productivity of semiconductor devices.

The resist removing composition according to the present invention is not only excellent in resist removing ability, but also effectively removing polymers, organometallic polymers, and metal oxides. In addition, the lower film exposed to the resist removing composition is not damaged. Therefore, when using the resist removal composition according to the present invention, a resist removal pretreatment step for removing residues such as polymers and a post-treatment step for preventing damage to the underlying film are unnecessary. Thus, the resist removal process can be simplified and the processing time can be shortened. In addition, the resist removing apparatus for using the resist removing composition according to the present invention can also be simplified and reduced in weight. In addition, since the resist removing composition according to the present invention has a viscosity suitable for rinsing with deionized water, it may be rinsed with deionized water after removing the resist.

Claims (23)

Alkoxy N-hydroxyalkyl alkanamides; At least one compound selected from the group consisting of alkanol amines, polar substances having a dipole moment of at least 3 and damage inhibitors; And A resist removal composition comprising a hydroxyammonium salt. The composition of claim 1, wherein the alkoxy N-hydroxyalkyl alkanamide is represented by the following formula (1). <Formula 1> R ₄ -OR ₃ -CO-NR ₁ R ₂ OH Wherein R ₁ is H atom, hydrocarbon having 1 to 5 carbon atoms or aromatic hydrocarbon having 1 to 3 ring structures, R ₂ is aromatic hydrocarbon having 1 to 5 hydrocarbons or 1 to 3 ring structures, R ₃ and R ₄ each represent a hydrocarbon having 1 to 5 carbon atoms. The composition of claim 1, wherein the alkanol amine is represented by the following Formula 2. <Formula 2> R ₁ -NH-R ₂ OH Wherein R ₁ represents an H atom, an aromatic hydrocarbon having 1 to 5 carbon atoms or 1 to 3 ring structures, and R ₂ represents an aromatic hydrocarbon having 1 to 5 hydrocarbons or 1 to 3 ring structures . The resist removal composition of claim 1, wherein the polar material is water, methanol or dimethyl sulfoxide. The method of claim 1, wherein the damage preventing agent is a compound for removing a resist, characterized in that the compound represented by the formula <Formula 3> R _6- (OH) _n In the above formula, R ₆ is a hydrocarbon having 1 to 5 carbon atoms, a hydrocarbon having 1 to 5 carbon atoms bonded to a -COOH group, an aromatic hydrocarbon having 1 to 3 ring structures or a 1 to 3 bonded to a -COOH group An aromatic hydrocarbon having three ring structures, n is an integer and represents 1-4. The composition of claim 1, wherein the hydroxyammonium salt is hydroxyammonium sulfate. The composition of claim 1, wherein the content of the alkoxy N-hydroxyalkyl alkanamide is 30 wt% to 99.9 wt% based on the total weight of the resist removal composition. According to claim 1, wherein the content of the alkanol amine is a resist removal composition, characterized in that 0.01% to 30% by weight based on the total weight of the resist removal composition. The composition of claim 1, wherein the polar material is present in an amount of about 0.01 wt% to about 30 wt% based on the total weight of the resist removal composition. The resist removal composition of claim 1, wherein the amount of the damage preventing agent is 0.01 wt% to 30 wt% with respect to the total weight of the resist removal composition. The composition of claim 1, wherein the hydroxyammonium salt is present in an amount of 0.01 wt% to 30 wt% based on the total weight of the resist removal composition. Providing a substrate; Forming a resist film on the substrate; And The substrate is contacted with a resist removing composition comprising a hydroxyammonium salt and at least one compound selected from the group consisting of alkoxy N-hydroxyalkyl alkanamides, alkanol amines, polar materials having a dipole moment of 3 or more, and damage inhibitors. And removing the resist film from the resist. The method of claim 12, wherein the alkoxy N-hydroxyalkyl alkanamide is represented by Formula 1 below. <Formula 1> R ₄ -OR ₃ -CO-NR ₁ R ₂ OH Wherein R ₁ is H atom, hydrocarbon having 1 to 5 carbon atoms or aromatic hydrocarbon having 1 to 3 ring structures, R ₂ is aromatic hydrocarbon having 1 to 5 hydrocarbons or 1 to 3 ring structures, R ₃ and R ₄ each represent a hydrocarbon having 1 to 5 carbon atoms. The method of claim 12, wherein the alkanol amine is represented by the following formula (2). <Formula 2> R ₁ -NH-R ₂ OH In the above formula, R ₁ represents an H atom, a hydrocarbon having 1 to 5 carbon atoms or an aromatic hydrocarbon having 1 to 3 ring structures, and R ₂ represents an aromatic hydrocarbon having 1 to 5 hydrocarbons or 1 to 3 ring structures. . 13. The method of claim 12, wherein said polar material is water, methanol or dimethyl sulfoxide. The method of claim 12, wherein the damage preventing agent is a compound represented by Chemical Formula 3 below. <Formula 3> R _6- (OH) _n In the above formula, R ₆ is a hydrocarbon having 1 to 5 carbon atoms, a hydrocarbon having 1 to 5 carbon atoms bonded to a -COOH group, an aromatic hydrocarbon having 1 to 3 ring structures or a 1 to 3 bonded to a -COOH group An aromatic hydrocarbon having three ring structures, n is an integer and represents 1-4. The composition of claim 12, wherein the hydroxyammonium salt is hydroxyammonium salt sulfate. The method of claim 12, wherein the content of the alkoxy N-hydroxyalkyl alkanamide is 30 wt% to 99.9 wt% based on the total weight of the resist removal composition. The method of claim 12, wherein the alkanol amine content is 0.01 wt% to 30 wt% based on the total weight of the resist removal composition. The method of claim 12, wherein the polar material is present in an amount of about 0.01 wt% to about 30 wt% based on the total weight of the resist removing composition. The resist removal composition of claim 12, wherein the amount of the damage preventing agent is 0.01 wt% to 30 wt% with respect to the total weight of the resist removal composition. The method of claim 12, wherein the hydroxyammonium salt is present in an amount of 0.01 wt% to 30 wt% based on the total weight of the resist removal composition. 13. The method of claim 12, wherein after the contacting step Rinsing the substrate; And And removing the substrate.