CMP slurry composition for polishing copper and method for polishing copper using same

Abstract

The present disclosure provides a CMP slurry composition for polishing copper and a polishing method using the same. The CMP slurry composition includes: at least one solvent selected from a polar solvent and a non-polar solvent; an abrasive; and a corrosion inhibitor, wherein the corrosion inhibitor comprises a compound represented by Formula 1 or a salt thereof.

Description

[0001] CROSS REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0084854 filed in the Korean Intellectual Property Office on June 30, 2023, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The invention relates to a CMP slurry composition for polishing copper and a method for polishing copper using the same. Background Art

[0004] A process for polishing a copper film as a metal interconnection of a semiconductor device is required to ensure a sufficiently high polishing rate, good polishing selectivity of the copper film relative to a barrier metal or a dielectric, a suitable flatness level of the polished surface, and a low defect level. In particular, as the thickness of the interconnection and the semiconductor layer decreases due to pattern miniaturization, a CMP slurry capable of ensuring high flatness of the polished surface is required.

[0005] Methods for improving flatness generally include increasing the amount of corrosion inhibitor used, employing polymeric film forming agents, and reducing the size and / or content of the abrasive used. However, these methods result in a reduction in the polishing rate for copper, thereby creating a balance between polishing rate and flatness. Conventionally, triazole or tetrazole compounds have been used as corrosion inhibitors. However, while being able to provide a certain degree of corrosion protection when used in large quantities, such triazole or tetrazole compounds have the problem of reducing the polishing rate for copper. Summary of the invention

[0006] An object of the present invention is to provide a CMP slurry composition for polishing copper which can prevent corrosion of the copper film.

[0007] Another object of the present invention is to provide a CMP slurry composition for polishing copper, which can improve the flatness of a polished surface by reducing dishing or erosion while ensuring a high polishing rate with respect to a copper film.

[0008] Another object of the present invention is to provide a method for polishing copper, which comprises polishing a copper film using the CMP slurry composition for polishing copper according to the present invention.

[0009] One aspect of the present invention relates to a CMP slurry composition for polishing copper.

[0010] The CMP slurry composition for polishing copper comprises: at least one solvent selected from a polar solvent and a non-polar solvent; an abrasive; and a corrosion inhibitor, wherein the corrosion inhibitor comprises a compound represented by Formula 1 or a salt thereof.

[0011] [Formula 1]

[0012]

[0013] (wherein R1 and R2 are each independently hydrogen, a substituted or unsubstituted straight or branched C1 to C5 alkyl group, or a substituted or unsubstituted C6 to C 10 Aryl;

[0014] R3 is hydrogen or a substituted or unsubstituted linear or branched C1 to C3 alkyl group; and

[0015] R4 is a substituted or unsubstituted straight chain or branched C1 to C5 alkyl group, a substituted or unsubstituted straight chain or branched C2 to C5 alkenyl group, or a substituted or unsubstituted straight chain or branched C2 to C5 alkynyl group).

[0016] The polishing method according to the present invention comprises polishing a copper film using the CMP slurry composition for polishing copper according to the present invention.

[0017] The invention provides a CMP slurry composition for polishing copper, which can prevent corrosion of copper film.

[0018] The present invention provides a CMP slurry composition for polishing copper, which can improve the flatness of a polished surface by reducing dishing or erosion while ensuring a high polishing rate with respect to a copper film.

[0019] The present invention provides a method for polishing copper, which comprises polishing a copper film using the CMP slurry composition for polishing copper according to the present invention. DETAILED DESCRIPTION

[0020] The terms used herein are for the purpose of describing exemplary embodiments and are not intended to limit the present invention.As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0021] The CMP slurry composition for polishing copper according to the present invention comprises: at least one solvent selected from a polar solvent and a non-polar solvent; an abrasive; and a corrosion inhibitor, wherein the corrosion inhibitor comprises a compound represented by Formula 1 or a salt thereof:

[0022] [Formula 1]

[0023]

[0024] (wherein R1 and R2 are each independently hydrogen, substituted or unsubstituted C1 to C5 alkyl, or substituted or unsubstituted C6 to C 10 Aryl;

[0025] R3 is hydrogen or substituted or unsubstituted C1 to C3 alkyl; and

[0026] R4 is a substituted or unsubstituted C1 to C5 alkyl, a substituted or unsubstituted C2 to C5 alkenyl, or a substituted or unsubstituted C2 to C5 alkynyl).

[0027] As used herein, the term "substituted or unsubstituted" means that at least one hydrogen atom in the corresponding functional group is replaced by C1 to C 10 Alkyl, C2 to C 10 Alkenyl, C2 to C 10 Alkynyl, C6 to C 20 Aryl, C7 to C 20 Aralkyl, C3 to C 20 Heteroaryl, C3 to C 10 Substituted with alicyclic groups, hydroxyl groups, amino groups, etc.

[0028] The CMP slurry composition according to the present invention can prevent corrosion of the copper film. In addition, the CMP slurry composition according to the present invention can improve the flatness of the polished surface by reducing dishing or erosion while minimizing the reduction in the polishing rate with respect to the copper film. In addition, compared with a conventional composition comprising a compound represented by Formula 1 or a salt thereof as a corrosion inhibitor, the CMP slurry composition according to the present invention can provide improved flatness of the polished surface without sacrificing a high polishing rate with respect to the copper film.

[0029] Hereinafter, each component of the CMP slurry composition for polishing copper (hereinafter referred to as "CMP slurry composition") according to the present invention will be described in detail.

[0030] At least one solvent selected from polar solvents and non-polar solvents can reduce the friction of the abrasive on the copper film when the abrasive is used to polish the copper film. At least one selected from polar solvents and non-polar solvents can contain water (e.g., ultrapure water), organic amines, organic alcohols, organic alcohol amines, organic ethers, organic ketones, etc. Preferably, at least one selected from polar solvents and non-polar solvents can contain ultrapure water, i.e., deionized water. At least one selected from polar solvents and non-polar solvents can be present in the CMP slurry composition in an amount of, for example, 30 wt % to 99 wt %.

[0031] The abrasive may include a typical abrasive for copper polishing. For example, the abrasive may be abrasive particles of a metal oxide or a non-metal oxide. The abrasive may include, for example, at least one selected from silica (e.g., colloidal silica and fumed silica), alumina, ceria, titania, and zirconium oxide. In one embodiment, the abrasive may be silica (e.g., colloidal silica), but is not limited thereto.

[0032] The abrasive is composed of spherical or non-spherical particles and may have an average primary particle size (D 50 Within this range, the abrasive can ensure a high polishing rate with respect to the copper film, prevention of scratches, and improved flatness of the polished surface. Herein, the “average particle size (D 50 )" is a typical particle size measurement known in the art and refers to the particle size corresponding to 50 volume % of the abrasive particles when the abrasive particles are distributed in order from smallest to largest by volume.

[0033] The abrasive may be a non-surface-modified abrasive or a surface-modified abrasive. Surface-modified abrasive particles may be more stably dispersed in the CMP composition and / or may polish the copper film at a higher polishing rate. The surface modification of the abrasive may be performed by treating the abrasive with a compound for surface modification. In one embodiment, the compound for surface modification may include a silane compound. When the abrasive is silicon dioxide, the abrasive may be easily surface-modified with a silane compound. The silane compound may include at least one selected from the following: alkoxysilane containing a mercapto group, alkoxysilane containing an amino group, tetraalkoxysilane, and C1 to C 10 In another embodiment, the silicon dioxide can be firstly surface-modified with a compound containing a sulfonic acid group or a phosphoric acid group, and then secondarily surface-modified with an alkoxysilane (eg, tetraethoxysilane).

[0034] The abrasive may be present in the CMP slurry composition in an amount of 0.001 wt % to 20 wt %, preferably 0.005 wt % to 10 wt %, more preferably 0.01 wt % to 5 wt %, and still more preferably 0.05 wt % to 3 wt %. Within this range, it is possible to ensure a sufficient polishing rate with respect to the copper film, prevention of scratches, and improved dispersion stability of the composition.

[0035] The corrosion inhibitor includes a compound represented by Formula 1 or a salt thereof.

[0036] [Formula 1]

[0037]

[0038] (wherein R1 and R2 are each independently hydrogen, a substituted or unsubstituted straight or branched C1 to C5 alkyl group, or a substituted or unsubstituted C6 to C 10 Aryl;

[0039] R3 is hydrogen or substituted or unsubstituted linear or branched C1 to C5 alkyl; and

[0040] R4 is a substituted or unsubstituted straight chain or branched C1 to C5 alkyl group, a substituted or unsubstituted straight chain or branched C2 to C5 alkenyl group, or a substituted or unsubstituted straight chain or branched C2 to C5 alkynyl group).

[0041] The compound represented by Formula 1 or its salt can prevent corrosion of the copper film. The compound represented by Formula 1 or its salt can improve the flatness of the polished surface by reducing surface defects (e.g., corrosion) while minimizing the reduction in the polishing rate with respect to the copper film. The compound represented by Formula 1 or its salt can significantly improve the flatness of the polished surface even in a small amount compared to conventional triazole-based or tetrazole-based corrosion inhibitors.

[0042] Preferably, R1 to R3 are each independently hydrogen or methyl.

[0043] Preferably, R4 is a substituted or unsubstituted linear or branched C1 to C5 alkyl group. The substituted or unsubstituted linear or branched C1 to C5 alkyl group can increase the solubility of the compound represented by Formula 1 or its salt in water, thereby facilitating the preparation of the CMP slurry composition and allowing the compound represented by Formula 1 or its salt to provide the desired effect even in a small amount. For example, R4 can be allyl, n-propyl, n-butyl, isobutyl, pentyl (n-pentyl) or isopentyl.

[0044] The compound represented by Formula 1 may be a compound represented by one of Formula 1-1 to Formula 1-6:

[0045] [Formula 1-1]

[0046]

[0047] [Formula 1-2]

[0048]

[0049] [Formula 1-3]

[0050]

[0051] [Formula 1-4]

[0052]

[0053] [Formula 1-5]

[0054]

[0055] [Formula 1-6]

[0056]

[0057] The compound of formula 1 can be prepared by a typical method known to those skilled in the art. For example, the compound represented by formula 1 can be prepared by introducing an azo or azo group into an amino-containing azole compound through nitrogenation of the azole compound, followed by reaction with NHR3R4 (wherein R3 and R4 are the same as defined in formula 1).

[0058] The salt of the compound of Formula 1 may be prepared by reacting the compound represented by Formula 1 with an acid or a base, but is not limited thereto.

[0059] The compound represented by Formula 1 or its salt may be present in the corrosion inhibitor in an amount of 1 wt % to 100 wt %, for example 5 wt % to 100 wt % or 50 wt % to 100 wt %. Within this range, the compound represented by Formula 1 or its salt may provide the desired effects described above.

[0060] The corrosion inhibitor may further include a corrosion inhibitor other than the compound represented by Formula 1. The corrosion inhibitor other than the compound represented by Formula 1 may include at least one selected from among a triazole-based corrosion inhibitor and a tetrazole-based corrosion inhibitor.

[0061] The triazole corrosion inhibitor may include: triazole compounds, including 1,2,4-triazole, 1,2,3-triazole, etc.; diaminotriazole compounds, including 3,5-diamino-1,2,4-triazole, etc.; methylbenzotriazole compounds, including 5-methylbenzotriazole, 4-methylbenzotriazole, etc.; and benzotriazole compounds, including ethylbenzotriazole, propylbenzotriazole, butylbenzotriazole, pentylbenzotriazole, hexylbenzotriazole, etc. The triazole corrosion inhibitor may be present in the CMP slurry composition in the form of the triazole corrosion inhibitor itself or a salt thereof.

[0062] The tetrazole corrosion inhibitor may include at least one selected from tetrazole, 5-aminotetrazole, 5-methyltetrazole and 5-phenyltetrazole, but is not limited thereto. The tetrazole corrosion inhibitor may be present in the CMP slurry composition in the form of the tetrazole corrosion inhibitor itself or a salt thereof.

[0063] The corrosion inhibitor may be present in the CMP slurry composition in an amount of 0.001 wt % to 5 wt %, preferably 0.005 wt % to 0.5 wt %. Within this range, the CMP slurry composition can significantly improve the flatness of the polished surface by reducing surface defects (e.g., corrosion) during polishing while providing an increased polishing rate for the copper film.

[0064] The CMP slurry composition may further include at least one selected from a chelating agent and an oxidizing agent.

[0065] The chelating agent chelates metal cations and metal oxides generated when the copper film is polished. Therefore, the chelating agent can ensure the suppression of the re-adsorption of the metal oxides onto the copper film, the increase in the polishing rate of the copper film, and the reduction in surface defects.

[0066] The chelating agent may include at least one selected from the following: an organic acid, a salt of an organic acid, an amino acid, a salt of an amino acid, an alcohol (e.g., a diol, a triol, and a polyol), an amine-containing compound, phosphoric acid, and a phosphate. Preferably, the chelating agent is an amino acid. In this article, unlike an amino acid, "organic acid" may refer to an acid that does not contain an amino group (-NH2). Using an amino acid as a chelating agent can provide an increased polishing rate for a copper film compared to using an organic acid or a salt thereof or a phosphate as a chelating agent.

[0067] The organic acid may comprise an organic carboxylic acid having one or more carboxyl groups. For example, the organic acid may comprise a saturated acid such as glycolic acid, lactic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, formic acid, salicylic acid, dimethylbutyric acid, octanoic acid, benzoic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and pimelic acid, maleic acid, fumaric acid, itaconic acid, phthalic acid and citric acid. For example, the salt of the organic acid may comprise ammonium citrate, ammonium acetate, etc.

[0068] The amino acid may include at least one selected from the group consisting of glycine, alanine, serine, asparagine, glutamic acid, proline, hydroxyproline, arginine, cystine, histidine, tyrosine, leucine, lysine, methionine, valine, isoleucine, threonine, tryptophan, and phenylalanine. Preferably, the amino acid is glycine, which may provide a further increased polishing rate for copper films.

[0069] The phosphate may include triammonium phosphate, hydrated triammonium phosphate, and the like.

[0070] The chelating agent may be present in the CMP slurry composition in an amount of 0.01 wt % to 10 wt %, preferably 0.1 wt % to 5 wt %. Within this range, the chelating agent may improve the polishing rate, dispersion stability of the composition and post-polishing surface properties of the copper film.

[0071] The oxidizing agent may promote the polishing of the copper film by oxidizing the copper film, and may improve the surface roughness of the copper film after polishing by smoothing the surface of the copper film.

[0072] The oxidizing agent may include at least one selected from the following: an inorganic per-compound, an organic per-compound, bromic acid or its salt, nitric acid or its salt, chloric acid or its salt, chromic acid or its salt, iodic acid or its salt, iron or its salt, copper or its salt, rare earth metal oxide, transition metal oxide and potassium dichromate. Herein, "per-compound" refers to a compound containing at least one peroxide group (-OO-) or containing an element in the highest oxidation state. Preferably, the oxidizing agent is a per-compound. For example, the per-compound may include at least one selected from hydrogen peroxide, potassium periodate, calcium persulfate and potassium ferrocyanide. Preferably, the per-compound is hydrogen peroxide.

[0073] The oxidizing agent may be present in the CMP slurry composition in an amount of 0.1 wt % to 5 wt %, preferably 0.5 wt % to 3 wt %. Within this range, the CMP slurry composition may exhibit good polishing performance.

[0074] The CMP slurry composition may further include a pH adjuster. The pH adjuster may include an organic base, such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, sodium carbonate, and potassium carbonate. Alternatively, the pH adjuster may include an inorganic acid, such as at least one selected from nitric acid, phosphoric acid, hydrochloric acid, and sulfuric acid. The pH adjuster may be present in the CMP slurry composition in an amount of 1 wt % or less.

[0075] The CMP slurry composition may further include typical additives such as surfactants, dispersants, modifiers, and biocides.

[0076] The CMP slurry composition may have a pH of 5 to 9 (preferably, 6 to 8).

[0077] The polishing method according to the present invention comprises polishing a copper film using the CMP slurry composition according to the present invention.

[0078] Then, the present invention will be described in more detail with reference to some examples. It should be understood that these examples are provided for illustration only and should not be interpreted as limiting the present invention in any way.

[0079] Example 1

[0080] After 0.084 g (0.001 mol) of 3-amino-1,2,4-triazole was dissolved in 100 g of distilled water, 0.101 g (36 wt%, 0.001 mol) of HCl was added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 g (5 wt%, 0.001 mol) of NaNO2 was slowly added dropwise thereto, and the resulting product was then stirred and allowed to stand for 1 hour to prepare an azo salt. After 0.057 g (0.001 mmol) of allylamine was dissolved in a mixture of 50 g of ethanol and 50 g of ultrapure water, 4 g of a 2.5 M NaOH aqueous solution was added to the solution, which was then added dropwise to a reactor containing an azo salt for 30 minutes. Thereafter, the resulting product was stirred and allowed to stand for 1 hour, and then dried under reduced pressure to obtain 0.145 g of a compound represented by Formula 1-1. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-1 was prepared. NMR results: 1H NMR, 4.01 (2H), 4.91-5.07 (2H), 5.93 (1H), 8.01 (1H).

[0081] The CMP slurry composition was prepared by stirring 0.33 wt % of an abrasive (colloidal silica, NP60, average particle size: 50 nm), 1.3 wt % of glycine (solid, J LCHEM Co., Ltd.) as a chelating agent, 0.02 wt % of the prepared compound (compound represented by Formula 1-1) as a corrosion inhibitor, and the remainder of ultrapure water, based on the total weight of the CMP slurry composition. A pH adjuster (nitric acid or potassium hydroxide) was used to adjust the CMP slurry composition to a pH of 7.3. Thereafter, 1.00 wt % of hydrogen peroxide (liquid, DONGWOO Fine-Chem Co., Ltd.) as an oxidizing agent was added, thereby obtaining a CMP slurry composition for evaluating the properties shown in Table 1. In Table 1, "-" means that the corresponding component was not used.

[0082] Example 2

[0083] After 0.084 g (0.001 mol) of 3-amino-1,2,4-triazole was dissolved in 100 g of distilled water, 0.101 g (36 wt%, 0.001 mol) of HCl was added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 g (5 wt%, 0.001 mol) of NaNO2 was slowly added dropwise thereto, and the resulting product was then stirred and allowed to stand for 1 hour to prepare an azo salt. After 0.059 g (0.001 mmol) of n-propylamine was dissolved in a mixture of 50 g of ethanol and 50 g of ultrapure water, 4 g of 2.5 M NaOH aqueous solution was added to the solution, which was then added dropwise to a reactor containing an azo salt for 30 minutes. Thereafter, the resulting product was stirred and allowed to stand for 1 hour, and then dried under reduced pressure to obtain 0.146 g of a compound represented by Formula 1-2. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-2 was prepared. NMR results: 1H NMR, 3.43 (2H), 6.53-6.81 (2H), 8.18 (1H).

[0084] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content (unit: weight %) of each component of the composition were changed as listed in Table 1.

[0085] Example 3

[0086] After 0.084 grams (0.001 moles) of 3-amino-1,2,4-triazole was dissolved in 100 grams of distilled water, 0.101 grams (36 weight %, 0.001 moles) of HCl were added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 grams (5 weight %, 0.001 moles) of NaNO2 were slowly added dropwise thereto, the product was then stirred and allowed to stand for 1 hour, thereby preparing azo salts. After 0.073 grams (0.001 millimoles) of n-butylamine was dissolved in 100 grams of ultrapure water, 4 grams of 2.5M NaOH aqueous solution were added to the solution, which was then added dropwise to a reactor containing azo salts for 30 minutes. Thereafter, the product was stirred and allowed to stand for 1 hour, then dried under reduced pressure, thereby obtaining 0.15 grams of the compound represented by Formula 1-3. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-3 was prepared. NMR results: 1H NMR, 0.88 (3H), 1.31 (2H), 1.67 (2H), 3.61 (2H), 8.01 (1H).

[0087] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content of each component of the composition were changed as listed in Table 1.

[0088] Example 4

[0089] After 0.084 grams (0.001 moles) of 3-amino-1,2,4-triazole was dissolved in 100 grams of distilled water, 0.101 grams (36 weight %, 0.001 moles) of HCl were added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 grams (5 weight %, 0.001 moles) of NaNO2 were slowly added dropwise thereto, the product was then stirred and allowed to stand for 1 hour, thereby preparing azo salts. After 0.071 grams (0.001 millimoles) of isobutylamine was dissolved in 100 grams of ultrapure water, 4 grams of 2.5M NaOH aqueous solution were added to the solution, which was then added dropwise to a reactor containing azo salts for 30 minutes. Thereafter, the product was stirred and allowed to stand for 1 hour, then dried under reduced pressure, thereby obtaining 0.15 grams of the compound represented by Formula 1-4. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-4 was prepared. NMR results: 1H NMR, 0.94 (6H), 1.81 (1H), 3.30 (2H), 8.01 (1H).

[0090] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content of each component of the composition were changed as listed in Table 1.

[0091] Example 5

[0092] After 0.084 grams (0.001 moles) of 3-amino-1,2,4-triazole was dissolved in 100 grams of distilled water, 0.101 grams (36 weight %, 0.001 moles) of HCl were added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 grams (5 weight %, 0.001 moles) of NaNO2 were slowly added dropwise thereto, the product was then stirred and allowed to stand for 1 hour, thereby preparing azo salts. After 0.088 grams (0.001 millimoles) of amylamine was dissolved in 100 grams of ultrapure water, 4 grams of 2.5M NaOH aqueous solution were added to the solution, which was then added dropwise to a reactor containing azo salts for 30 minutes. Thereafter, the product was stirred and allowed to stand for 1 hour, then dried under reduced pressure, thereby obtaining 0.162 grams of the compound represented by Formula 1-5. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-5 was prepared. NMR results: 1H NMR, 0.87 (3H), 1.22-1.42 (4H), 1.69 (2H), 3.61 (2H), 8.01 (1H).

[0093] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content of each component of the composition were changed as listed in Table 1.

[0094] Example 6

[0095] After 0.084 grams (0.001 moles) of 3-amino-1,2,4-triazole was dissolved in 100 grams of distilled water, 0.101 grams (36 weight %, 0.001 moles) of HCl were added to the solution, which was then vigorously stirred in an ice-water bath at 0°C to 5°C. Thereafter, 1.3 grams (5 weight %, 0.001 moles) of NaNO2 were slowly added dropwise thereto, the product was then stirred and allowed to stand for 1 hour, thereby preparing azo salts. After 0.088 grams (0.001 millimoles) of isopentylamine was dissolved in 100 grams of ultrapure water, 4 grams of 2.5M NaOH aqueous solution were added to the solution, which was then added dropwise to a reactor containing azo salts for 30 minutes. Thereafter, the product was stirred and allowed to stand for 1 hour, then dried under reduced pressure, thereby obtaining 0.162 grams of the compound represented by Formula 1-6. The NMR results obtained for the prepared compound are as follows, which show that the compound represented by Formula 1-6 was prepared. NMR results: 1H NMR, 0.88 (6H), 1.43-1.60 (3H), 3.63 (2H), 8.01 (1H).

[0096] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content of each component of the composition were changed as listed in Table 1.

[0097] Comparative Example 1 to Comparative Example 3

[0098] A CMP slurry composition was prepared in the same manner as in Example 1, except that the type and content of each component of the composition were changed as listed in Table 1.

[0099] Each of the CMP slurry compositions prepared in Examples 1 to 6 and Comparative Examples 1 to 3 was evaluated according to the properties shown in Table 1. The results are shown in Table 1.

[0100] (1) Copper film polishing rate (unit: angstrom / minute):

[0101] A blanket wafer (diameter: 300 mm) having a copper film formed on a silicon oxide film was polished under the following conditions, and then the change in sheet resistance before and after polishing was converted into an etching thickness, thereby calculating a polishing rate.

[0102] Polishing machine: Reflexion LK 300mm (AMAT Co., Ltd.)

[0103] Polishing pad: IC1000

[0104] Polishing Time: Polishing time varies depending on the amount of blanket wafer being polished.

[0105] Head speed per minute: 87 rpm

[0106] Platen speed per minute: 98 rpm

[0107] Flow rate: 200 ml / min

[0108] Pressure: 1.0 psi

[0109] Polishing rate measurement: using a sheet resistance meter.

[0110] (2) Erosion (unit: nanometer): The polishing solution was allowed to stand at 60° C. for 1 hour. After polishing the patterned wafer under the same conditions as in (1), the profile of the wafer pattern was measured using an atomic force profiler (InSight CAP, Bruker Co., Ltd.). The erosion was calculated based on the height difference between the surrounding oxide film and the unit oxide film in the 0.18 μm×0.18 μm patterned area of ​​the polished wafer. Here, the scanning rate was set to 100 μm / sec and the scanning length was set to 2 mm.

[0111] Table 1

[0112]

[0113] As can be seen from Table 1, the CMP slurry composition according to the present invention provides improved flatness of the polished surface by reducing surface defects (eg, corrosion) without sacrificing a high polishing rate with respect to copper films.

[0114] In contrast, the CMP slurry composition of the comparative example not containing the compound represented by Formula 1 according to the present invention fails to provide improved flatness of the polished surface and increased polishing rate with respect to the copper film.

[0115] It should be understood that various modifications, changes, alterations and equivalent embodiments may be made by those skilled in the art without departing from the spirit and scope of the present invention.

Claims

1. A CMP slurry composition for polishing copper, comprising: At least one solvent selected from polar solvents and non-polar solvents; Abrasives; as well as Corrosion inhibitors, wherein the corrosion inhibitor comprises a compound represented by Formula 1 or a salt thereof, [Formula 1] wherein R1 and R2 are each independently hydrogen, a substituted or unsubstituted straight or branched C1 to C5 alkyl group, or a substituted or unsubstituted C6 to C 10 Aryl; R3 is hydrogen or substituted or unsubstituted linear or branched C1 to C3 alkyl; and R4 is a substituted or unsubstituted straight chain or branched C1 to C5 alkyl group, a substituted or unsubstituted straight chain or branched C2 to C5 alkenyl group, or a substituted or unsubstituted straight chain or branched C2 to C5 alkynyl group.

2. The CMP slurry composition for polishing copper according to claim 1, wherein the compound represented by Formula 1 is a compound represented by one of Formulas 1-1 to 1-6, [Formula 1-1] [Formula 1-2] [Formula 1-3] [Formula 1-4] [Formula 1-5] [Formula 1-6] 3. The CMP slurry composition for polishing copper according to claim 1, wherein the corrosion inhibitor is present in the CMP slurry composition in an amount of 0.001 wt % to 5 wt %.

4. The CMP slurry composition for polishing copper according to claim 1, wherein the corrosion inhibitor further comprises a corrosion inhibitor other than the compound represented by Formula 1.

5. The CMP slurry composition for polishing copper according to claim 4, wherein the corrosion inhibitor other than the compound represented by Formula 1 includes at least one selected from a triazole-based corrosion inhibitor and a tetrazole-based corrosion inhibitor.

6. The CMP slurry composition for polishing copper according to claim 1, further comprising: At least one selected from a chelating agent and an oxidizing agent.

7. The CMP slurry composition for polishing copper according to claim 6, comprising: 0.001 wt % to 20 wt % of said abrasive; 0.001 wt % to 5 wt % of said corrosion inhibitor; 0.01 wt % to 10 wt % of said chelating agent; 0.1 wt % to 5 wt % of said oxidizing agent; and The remainder of the solvent.

8. A method for polishing copper, comprising: A copper film is polished using the CMP slurry composition for polishing copper as claimed in any one of claims 1 to 7.

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