JP2009238954A - Metal polishing composition and chemical mechanical polishing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal polishing composition excellent in polishing speed of a conductor film mainly made of copper or copper alloy, having the polishing speed uniform within a plane of the conductor film and capable of production of a semiconductor device with improved flatness, and a chemical mechanical polishing method using the composition. <P>SOLUTION: The metal polishing composition contains (a) a hetero aromatic ring compound having a hydroxyl group as a substituent and having a six-membered ring and a five-membered ring containing hetero atoms in a ring-fused structure, (b) peroxodisulfate and (c) abrasive grains, and is used for chemical mechanical polishing the conductor film mainly made of copper or copper alloy during a semiconductor device manufacturing process, and the chemical mechanical polishing method employs the composition. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a metal polishing composition used for chemical mechanical planarization in a semiconductor device manufacturing process, and a polishing method using the same.

In the development of semiconductor devices typified by semiconductor integrated circuits (hereinafter sometimes referred to as “LSI”), in order to increase the integration and speed of semiconductor devices, wiring miniaturization and lamination methods are studied. Has been.
As a technology for this purpose, chemical mechanical polishing (Chemical Mechanical Polishing)
Polishing, hereinafter referred to as “CMP”. Etc.) are employed. CMP is used to polish an interlayer insulating film (such as SiO ₂ ) or a metal thin film used for wiring to smooth the substrate or remove an excess metal thin film during wiring formation (for example, patents). Reference 1).

A general method of CMP is as follows.
A polishing pad is affixed on a circular polishing platen (platen), and the surface of the polishing pad is immersed in a polishing liquid. The surface of the substrate (wafer) is pressed against the polishing pad, and both the polishing surface plate and the substrate are rotated with a predetermined pressure (polishing pressure) applied from the back surface.
In CMP, the surface of the substrate is flattened by mechanical friction generated by the above operation.

  Conventionally, tungsten and aluminum have been widely used in interconnect structures as wiring metals. However, LSIs using copper, which has lower wiring resistance than these metals, have been developed with the aim of achieving higher performance. As a method for wiring this copper, a damascene method is known (for example, see Patent Document 2). Further, a dual damascene method in which a contact hole and a wiring groove are simultaneously formed in an interlayer insulating film and a metal is embedded in both has been widely used. As a target material for copper wiring, a high-purity copper target of five nines or more is shipped.

  However, in recent years, in order to miniaturize the wiring in accordance with the demand for higher density, improvements in the conductivity and electronic characteristics of the copper wiring are required. On the other hand, the use of a copper alloy obtained by adding a third component to high-purity copper has begun to be studied.

  There is also a need for high-speed metal polishing means that can increase productivity without contaminating these high-definition and high-purity materials. In particular, since copper is a soft metal, when polishing copper or copper alloys, only the center is polished deeper, resulting in dish-like depressions (dishing), or the surface of multiple wiring metal surfaces is a dish. A phenomenon (erosion) that forms a concave-shaped recess and a polishing flaw (scratch) are likely to occur, and an increasingly accurate polishing technique is required.

  In recent years, wafers have become larger in order to improve productivity. Currently, wafers with a diameter of 200 mm or more are widely used, and the manufacture of wafers with a diameter of 300 mm or more has started. As the size of the wafer increases, the difference in polishing rate between the central portion and the peripheral portion of the wafer tends to increase, and there is a strong demand for uniform polishing within the wafer surface.

On the other hand, as a chemical polishing method in which mechanical polishing means is not applied to copper and a copper alloy, a chemical polishing method based only on a dissolving action is disclosed (for example, see Patent Document 3).
However, in the chemical polishing method, since polishing is performed only by a chemical dissolution action, problems such as dishing of recesses, that is, dishing, are likely to occur compared to CMP in which the metal film of the protrusions is selectively chemically and mechanically polished. Flatness has become an issue.

In addition, when copper wiring is used in LSI manufacturing, a diffusion prevention layer called a barrier layer is generally provided between the wiring portion and the insulating layer in order to prevent copper ions from diffusing into the insulating material. The barrier layer is formed of a barrier material such as TaN, TaSiN, Ta, TiN, Ti, Nb, W, WN, Co, Zr, ZrN, Ru, CuTa alloy, MnSi _x O _y and MnO _x , one layer or two More layers are provided.
Since these barrier materials have a conductive property, the barrier material on the insulating layer must be completely removed in order to prevent an error such as a leakage current. For this removal processing, a method similar to that for polishing the bulk of the metal wiring material can be applied. This is what is called barrier CMP.

  Further, in the bulk polishing of copper, dishing is likely to occur particularly in a wide metal wiring portion. Therefore, it is desirable that the amount of polishing and removal can be adjusted between the wiring portion and the barrier portion in order to be finally flattened. For this reason, it is desired that the polishing liquid for barrier polishing has an optimal polishing selectivity of copper / barrier metal. Further, since the wiring pitch and the wiring density are different in each level of the wiring layer, it is further desirable that the polishing selectivity can be adjusted as appropriate.

  A metal polishing composition (metal polishing composition) used for CMP generally contains solid abrasive grains (eg, alumina, silica) and an oxidizing agent (eg, hydrogen peroxide, peroxodisulfate). . The basic mechanism of CMP using such a metal polishing composition is considered to be that the metal surface is oxidized by an oxidizing agent and the oxide film is removed by abrasive grains (for example, polishing) (Refer nonpatent literature 1.).

A polishing agent containing peroxodisulfate has a feature that a high polishing rate can be obtained, but has a problem that dishing and erosion are likely to proceed. As one means for solving the dishing, benzotriazoles are used as an anticorrosive agent that suppresses polishing of a metal film (see, for example, Patent Document 4).
According to these methods, a protective film is formed on the metal film of the semiconductor substrate, and the metal film is left in the concave portion while the convex portion is removed by the abrasive grains, thereby obtaining a desired conductor pattern. Occurrence of dishing is suppressed by the protective film of the recess, and high flatness is obtained.

However, when peroxodisulfuric acid is used, there is a problem that part of the surface of the semiconductor substrate is excessively polished due to the strong oxidizing power of this peroxodisulfuric acid. There was a need for further improvements.
US Pat. No. 4,944,836 JP-A-2-278822 JP 49-122432 A JP-A-2005-116987 Journal of Electrochemical Society, 1991, 138, 11, 3460-3464 Journal of Electrochemical Society, 2000, Vol. 147, No. 10, pages 3907-3913

  An object of the present invention is to make it possible to fabricate a semiconductor device that is excellent in the polishing rate of a conductor film mainly made of copper or a copper alloy, the polishing rate is uniform in the plane of the conductor film, and has improved flatness. The object is to provide a metal polishing composition and a chemical mechanical polishing method using the same.

As a result of intensive studies, the present inventors have found that the above problems can be solved by using a metal polishing composition containing a heteroaromatic ring compound having a specific structure, peroxodisulfate, and abrasive grains. The present invention has been reached.
That is, the object of the present invention is achieved by the following means.

<1> (a) a heteroaromatic ring compound having a hydroxyl group as a substituent and a 6-membered ring and a 5-membered ring containing a heteroatom fused, (b) peroxodisulfate, and (c) abrasive grains A metal polishing composition used for chemical mechanical polishing of a conductor film mainly comprising copper or a copper alloy in a semiconductor device manufacturing process.

<2> The metal polishing composition as described in <1> above, wherein the heteroaromatic ring compound is a compound represented by the following general formula (I) or the following general formula (II).

(In the above general formula (I), A represents a carbon atom or a nitrogen atom, X ¹ and Y each independently represent a hydrogen atom or a monovalent substituent, and at least one of X ¹ and Y is (In the general formula (II), X ² represents a hydroxyl group.)

<3> The metal polishing composition as described in <1> or <2> above, further comprising (d) an organic acid.
<4> The metal polishing composition according to any one of <1> to <3>, further comprising (e) a surfactant.
<5> The metal polishing composition as described in <4> above, wherein the surfactant (e) includes a surfactant represented by the following general formula (W).

(In the general formula (W), R represents a linear or branched alkyl group having 8 to 20 carbon atoms, Ar represents an aryl group, and M ⁺ represents a hydrogen ion, an alkali metal ion, or ammonium. .)

<6> The metal polishing composition according to any one of <1> to <5> above, wherein the abrasive grains (c) are colloidal silica.

<7> Supplying the metal polishing composition according to any one of <1> to <6> above to a polishing pad on a polishing platen, and rotating the polishing platen to thereby rotate the polishing pad A chemical mechanical polishing method in which polishing is carried out by making a relative movement while contacting a surface to be polished of a workpiece.

  ADVANTAGE OF THE INVENTION According to this invention, it is excellent in the grinding | polishing speed | rate of the conductor film which consists mainly of copper or a copper alloy, The grinding | polishing speed | rate is uniform in the surface of a conductor film, and manufacture of the semiconductor device with improved flatness is enabled. Metal polishing composition and chemical mechanical polishing method using the same Metal polishing composition and chemical mechanical polishing method using the same can be provided.

Hereinafter, specific embodiments of the present invention will be described.
[Metal polishing composition]
The metal polishing composition of the present invention comprises (a) a heteroaromatic ring compound having a hydroxyl group as a substituent and a condensed 6-membered ring and a 5-membered ring containing a hetero atom, (b) peroxodisulfate, And (c) is used for chemical mechanical polishing of a conductor film mainly containing copper or a copper alloy in a semiconductor device manufacturing process, including abrasive grains.
Moreover, you may contain another compound as needed.
The metal polishing composition of the present invention usually takes the form of a slurry obtained by dispersing (c) abrasive grains in an aqueous solution obtained by dissolving each component.
The metal polishing composition of the present invention is useful for chemical mechanical polishing of an object to be polished having a conductor film mainly composed of copper or a copper alloy in a semiconductor device manufacturing process.

The metal polishing composition of the present invention uses (a) a heteroaromatic ring compound having a hydroxyl group as a substituent and a condensed 6-membered ring and a 5-membered ring containing a heteroatom. By using disulfate and (c) abrasive grains in combination, the polishing rate of the conductor film made of copper or copper alloy is excellent, the polishing rate is uniform in the plane of the conductor film, and the flatness is improved. A semiconductor device can be manufactured. The reason for this is not clear, but (a) is
In order to suppress excessive oxidation of copper due to (b), it is considered to suppress excessive polishing rate in the surface. For this reason, the metal polishing composition of the present invention is excellent in the polishing rate of a conductor film made of copper or copper metal, the polishing rate is uniform in the plane of the conductor film, and the semiconductor device has improved flatness. Is produced.

  Although each component which comprises the metal polishing composition of this invention is explained in full detail below, each component may use only 1 type and may use 2 or more types together.

  In the present invention, the “metal polishing composition” (hereinafter also referred to as “polishing composition”) refers not only to a metal polishing composition having a composition (concentration) used for polishing, but also as required during use. In the present invention, the diluted polishing concentrate is also referred to as a metal polishing composition unless otherwise specified. When the concentrated liquid is used for polishing, it is diluted with water or an aqueous solution and used for polishing, and the dilution ratio is generally 1 to 20 times by volume.

<(A) Heteroaromatic compound having a hydroxyl group as a substituent and condensed with a 6-membered ring and a 5-membered ring containing a hetero atom>
The metal polishing composition of the present invention includes (a) a heteroaromatic ring compound having a hydroxyl group as a substituent and a condensed 6-membered ring and a 5-membered ring containing a heteroatom.

  Examples of the hetero atom in the heteroaromatic ring compound include a nitrogen atom, an oxygen atom, and a sulfur atom. Among these, as the hetero atom, a nitrogen atom is preferable for the purpose of improving the in-plane uniformity of the polishing rate.

The number of heteroatoms contained in the five-membered ring containing heteroatoms is preferably 1 to 3, particularly preferably 1 to 2, for the purpose of maintaining an appropriate polishing rate.
Examples of the 5-membered ring containing a hetero atom include an oxadiazole ring, an oxazole ring, a thiadiazole ring, a thiazole ring, an imidazole ring, a tetrazole ring, a pyrazole ring, a triazole ring, an isoxazole ring, and a thiatriazole ring. Among these, a pyrazole ring and an imidazole ring are preferable for maintaining an appropriate polishing rate.

  The number of hydroxyl groups contained as a substituent in the heteroaromatic ring compound is preferably 1 to 3, and more preferably 1 to 2.

  The 6-membered ring in the aromatic ring compound represents a benzene ring or a cyclohexane ring, and a benzene ring is preferred for the purpose of improving the in-plane uniformity of the polishing rate.

  The heteroaromatic ring compound used in the metal polishing composition of the present invention is preferably a compound represented by the following general formula (I) or the following general formula (II).

In the general formula (I), A represents a carbon atom or a nitrogen atom. In the general formula (I), X ¹ and Y each independently represent a hydrogen atom or a monovalent substituent, and at least one of X ¹ and Y represents a hydroxyl group. In the general formula (I), when only ^one of X ¹ and Y represents a hydroxyl group, the other may be any group, and representative groups include a methyl group, an ethyl group, and the like. . Examples of the monovalent substituent that X ¹ and Y each independently represent include a hydroxyl group and a methyl group. In the general formula (I), as X ¹ and Y, one is preferably a hydroxyl group and the other is a hydrogen atom. In the general formula (II), X ² represents a hydroxyl group.

  The compound represented by the above general formula (I) or the above general formula (II) may further have a carbon atom constituting a cyclic structure and further have a substituent, and the substituent is not particularly limited. Examples include a halogen atom, an alkyl group, an acyl group, a carboxy group, an amino group, a hydroxyl group, and an alkoxy group, more preferably an alkyl group, a carboxyl group, and a hydroxyl group, and particularly preferably an alkyl group.

  In the heteroaromatic ring compound used in the metal polishing composition of the present invention, the number of substituents that may be present in addition to the hydroxyl group is not particularly limited, but for reasons of improving the in-plane uniformity of the polishing rate. , Preferably 0 or 1, more preferably 0.

  Specific examples (I-1) to (I-4) and (II-1) to (II-2) of the heteroaromatic ring compound used in the metal polishing composition of the present invention will be given below. It is not limited to.

  Among these specific examples (I-1) to (I-4) and (II-1) to (II-2), specific examples (I-1) and (I- 2) is preferable, and specific example (I-1) is particularly preferable.

The total amount of the heteroaromatic ring compound used in the metal polishing composition of the present invention is 1 × 10 ⁻⁸ to 1 × 10 ⁻⁸ in 1 L of the metal polishing composition used for polishing, for the reason of maintaining an appropriate polishing rate. 1 × ¹⁰ -1 range of mol, more preferably in the range of ^{1 × 10 -7 ~1 × 10 -1} mol, more preferably in the range of ^{1 × 10 -6 ~1 × 10 -1} mol. In the range of this addition amount, the polishing rate becomes favorable, which is preferable.

<(B) Peroxodisulfate>
The metal polishing composition of the present invention contains (b) peroxodisulfate as a compound (oxidant) that can oxidize a metal (mainly copper or a copper alloy) that is a suitable polishing target.

  Among the peroxodisulfates, ammonium peroxodisulfate and potassium peroxodisulfate are preferable, and ammonium peroxodisulfate is most preferable.

  The amount of peroxodisulfate added is preferably 0.003 mol to 8 mol, more preferably 0.03 mol to 6 mol, more preferably 0.1 mol to 1 mol per liter of the polishing composition when used for polishing. 4 mol is particularly preferable. That is, the amount of (b) peroxodisulfate added is preferably 0.003 mol or more from the viewpoint of sufficient metal oxidation and ensuring a high CMP rate, and preferably 8 mol or less from the viewpoint of preventing roughening of the polished surface.

<(C) Abrasive grains>
The metal polishing composition of the present invention contains (c) abrasive grains. Preferred examples of the abrasive grains include silicon oxide particles (silica: precipitated silica, fumed silica, colloidal silica, synthetic silica), ceria, alumina, titania, zirconia, germania, manganese oxide, and the like. Among these, silicon oxide particles are preferable, and colloidal silica (particularly, colloidal silica of 20 nm or more and less than 50 nm) is particularly preferable.
The colloidal silica preferably has an association degree of 2 or less. Here, the degree of association means a value obtained by dividing the diameter of secondary particles formed by aggregation of primary particles by the diameter of primary particles (secondary particle diameter / primary particle diameter). A degree of association of 1 means only monodispersed primary particles. The secondary particle diameter is measured with an electron microscope or the like.

As a method for producing colloidal silica that can be preferably used as an abrasive, for example, Si (OC ₂ H ₅ ) ₄ , Si (sec-OC ₄ H ₉ ) ₄ , Si (OCH ₃ ) ₄ , Si (OC ₄ H ₉ ) ₄ are used. A preparation method in which such a silicon alkoxide compound is hydrolyzed by a sol-gel method is exemplified. The colloid obtained in this way has a very steep particle size distribution.

  The primary particle size of the abrasive grains is a particle size cumulative curve showing the relationship between the particle size of the abrasive grains and the cumulative frequency obtained by integrating the number of particles having the particle size, and the cumulative frequency of this curve is the point at which the cumulative frequency is 50%. It means the particle diameter. For example, LB-500 manufactured by HORIBA, Ltd. is used as a measuring device for obtaining the particle size distribution.

  When the abrasive grains are spherical, the values measured as they are can be adopted. However, the particle size of the amorphous particles is expressed by the diameter of a sphere that is equal to the particle volume. The particle size can be measured by various known methods such as photon correlation method, laser diffraction method, Coulter counter method, etc. In the present invention, observation with a scanning microscope or transmission electron micrograph is taken. Then, a method of obtaining and calculating the shape and size of each particle is used.

  The average particle size (primary particle size) of the abrasive grains contained in the metal polishing composition of the present invention is preferably in the range of 20 nm to 150 nm, more preferably 20 nm to less than 50 nm. Particles of 20 nm or more are preferred for the purpose of achieving a sufficient polishing speed. The particle diameter is preferably less than 50 nm for the purpose of preventing excessive frictional heat during polishing.

  In addition, not only the general inorganic abrasive grains as described above but also organic polymer particles can be used in combination as long as the effects of the present invention are not impaired. In addition, colloidal silica surface-modified with aluminate ions or borate ions, colloidal silica with controlled surface potential, colloidal silica with various surface treatments, composite abrasives made of multiple materials, etc. It is also possible to use it accordingly.

  Although the addition amount of the abrasive grain in this invention is suitably selected according to the objective, Generally, it can use in 0.001 mass%-20 mass% with respect to the total mass of the metal polishing composition. In the present invention, due to the effects of the addition of the components (1) and (2), excellent polishing characteristics can be exhibited even when the amount of abrasive grains added is less than 1.0% by mass. From the viewpoint of suppressing the amount, the addition amount of the abrasive grains is preferably less than 1.0% by mass, and more preferably in the range of 0.01 to 0.5% by mass.

  The metal polishing composition of the present invention may contain the following components as necessary in addition to the components described above. Hereinafter, optional components applicable to the polishing composition of the present invention will be described.

[(D) Organic acid]
The metal polishing composition according to the present invention preferably further contains an organic acid. The organic acid here is not a metal oxidizing agent, but has an action of promoting oxidation, adjusting pH, and buffering agent. Examples of the organic acid include organic acids and amino acids.

The organic acid is preferably water-soluble. In particular, those selected from the following group are more suitable.
That is, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, 2-methylbutyric acid, n-hexanoic acid, 3,3-dimethylbutyric acid, 2-ethylbutyric acid, 4-methylpentanoic acid, n-heptanoic acid, 2-methyl Hexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, apple Acids, tartaric acid, citric acid, lactic acid, hydroxyethyliminodiacetic acid, iminodiacetic acid, acedamidoiminodiacetic acid, nitrilotripropanoic acid, nitrilotrimethylphosphonic acid, tricine, and their ammonium and alkali metal salts Or a mixture thereof.

An amino acid is also preferably used as one of the organic acids. The amino acid is preferably water-soluble. Those selected from the following group are more suitable.
That is, glycine, L-alanine, β-alanine, L-2-aminobutyric acid, L-norvaline, L-valine, L-leucine, L-norleucine, L-isoleucine, L-alloisoleucine, L-phenylalanine, L- Proline, sarcosine, L-ornithine, L-lysine, taurine, L-serine, L-threonine, L-allothreonine, L-homoserine, L-tyrosine, 3,5-diiodo-L-tyrosine, β- (3 4-dihydroxyphenyl) -L-alanine, L-thyroxine, 4-hydroxy-L-proline, L-cystine, L-methionine, L-ethionine, L-lanthionine, L-cystathionine, L-cystine, L-cysteic acid , L-aspartic acid, L-glutamic acid, S- (carboxymethyl) -L-cysteine, 4-aminobutyric acid Acid, L-asparagine, L-glutamine, azaserine, L-arginine, L-canavanine, L-citrulline, δ-hydroxy-L-lysine, creatine, L-kynurenine, L-histidine, N-methylglycine, 1-methyl -L-histidine, 3-methyl-L-histidine, ergothioneine, L-tryptophan, actinomycin C1, apamin, angiotensin I, angiotensin II, antipine, etc. are mentioned.

In the metal polishing element of the present invention, the following dicarboxylic acid, tricarboxylic acid or aminocarboxylic acid is preferably used among the above organic acids for the purpose of maintaining an appropriate polishing rate.
That is, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid and their salts such as ammonium salts and alkali metal salts, or mixtures thereof, etc. Or glycine, N-methylglycine, iminodiacetic acid, methyliminodiacetic acid, nitrilotripropanoic acid, hydroxyethyliminodiacetic acid, L-alanine, β-alanine, glycylglycine, dihydroxyethylglycine, acedamidoiminodi Acetic acid, tricine and the like are preferable.

  The amount of the organic acid (d) added is preferably 0.005 mol to 0.5 mol, and preferably 0.01 mol to 0.3 mol in 1 L of the metal polishing composition used for polishing. More preferably, 0.05 mol to 0.3 mol is particularly preferable. That is, the addition amount of the organic acid is preferably 0.01 mol or more from the viewpoint of improving the polishing rate, and 0.3 mol or less is preferable from the viewpoint of not deteriorating dishing.

  In the metal polishing composition of the present invention, the organic acid may be used alone or in combination of two or more. These organic acids can be synthesized according to a conventional method, or commercially available products may be used.

[(E) Surfactant]
The metal polishing composition of the present invention preferably contains a surfactant.
The surfactant has an action of reducing the contact angle of the surface to be polished and has an action of promoting uniform polishing. The surfactant used is preferably selected from the group of anionic (anionic), cationic (cationic), nonionic (nonionic) and amphoteric (betaine) surfactants. .
Examples of the anionic surfactant include carboxylic acid, sulfonic acid, sulfate ester, phosphate ester and salts thereof.
Carboxylic acids and salts thereof include fatty acid salts (for example, beef tallow fatty acid soda, sodium stearate, potassium oleate, castor oil potash), N-acyl amino acid salts (for example, palm oil fatty acid sarcosine triethanolamine), polyoxyethylene Or a polyoxypropylene alkyl ether carboxylate and an acylated peptide are mentioned.

  Examples of sulfonic acids and salts thereof include alkyl sulfonates (for example, dioctyl sulfosuccinate ester salts), alkyl benzene sulfonic acids (for example, dodecyl benzene sulfonic acid (soft), (hard), ammonium dodecyl benzene sulfonate (soft), ( Hard), dodecylbenzenesulfonic acid triethanolamine), alkyl diphenyl ether disulfonate (eg, sodium alkyldiphenyl ether disulfonate), alkyl naphthalene sulfonate (eg, monoisopropyl naphthalene sulfonic acid, diisopropyl naphthalene sulfonic acid, triisopropyl naphthalene sulfone) Acid ammonium), alkylsulfosuccinates (eg sodium dialkylsulfosuccinate, polyoxyethylene lauryl ether) Disodium sulfosuccinate), α-olefin sulfonates, N-acyl sulfonates (for example, coconut oil fatty acid methyl taurine sodium, polyoxyethylene coconut oil aliphatic monoethanolamide sodium sulfate), naphthalene and other aromatic sulfonic acids Formalin condensates (for example, sodium salt of β-naphthalenesulfonic acid formalin condensate, sodium salt of special aromatic sulfonic acid formalin condensate).

Sulfated ester salts such as sulfated oils, alkyl sulfates (for example, sodium lauryl sulfate, higher alcohol sodium sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate), alkyl ether sulfates (for example, polyoxyethylene or polyoxypropylene alkyl ether) Examples thereof include sulfates (for example, sodium polyoxyethylene lauryl sulfate, polyoxyethylene lauryl ether sulfate triethanolamine) and alkylamide sulfates.
As phosphate ester salts, alkyl phosphates (eg, potassium octyl phosphate, potassium lauryl phosphate, potassium octyl ether phosphate), polyoxyethylene or polyoxypropylene alkylallyl ether phosphates (eg, polyoxyethylene alkylphenyl ether phosphate) Acid).

Examples of the nonionic surfactant include ether type, ether ester type, ester type, and nitrogen-containing type, and fluorine type surfactants and the like.
The ether type includes polyoxyalkylene alkyl and polyoxyalkylene alkyl phenyl ether (for example, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene higher alcohol ether, Polyoxyethylene myristel ether, polyoxyethylene octyldodecyl ether), polyoxyethylene derivatives (eg, polyoxyethylene disulfonated phenyl ether), polyoxyethylene polyoxypropylene glycol, alkylallyl formaldehyde condensed polyoxyethylene ether, polyoxy Ethylene polyoxypropylene block polymer, polyoxyethylene polyoxypropylene Ruki ether, and the like.

  Ether ester types include glycerin ester polyoxyethylene ether, polyoxyethylene fatty acid ester (eg, polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol distearate, polyoxyethylene hydrogenated castor oil), polyoxy Ethylene sorbitan fatty acid ester (for example, polyoxyethylene sorbitan monococonut oil fatty acid ester, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan tristearate, polyoxyethylene Oxyethylene sorbitan monooleate, polyoxyethylene sorbitan trioleate, polyoxyethylene sol Tan triisostearate, polyoxyethylene sorbitan mono coconut fatty acid ester, polyoxyethylene sorbit tetraoleate), include polyoxyethylene ethers of sorbitol esters.

Examples of the ester type include sorbitan fatty acid esters (for example, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sorbitan trioleate, sorbitan sesquioleate), glycerin fatty acid ester ( Examples thereof include glycerol monostearate and glycerol monooleate), polyglycerol ester, sorbitan ester, propylene glycol ester, and sucrose ester.
Examples of the nitrogen-containing type include fatty acid alkanolamide (for example, coconut fatty acid diethanolamide), polyoxyethylene alkylamine (for example, polyoxyethylene laurylamine), polyoxyethylene alkylamide (for example, polyoxyethylene lauric acid amide), and the like. Can be mentioned. Moreover, a fluorine-type surfactant, an acetylene containing nonionic surfactant (For example, diisobutyl dimethyl butynediol polyoxyethylene glycol ether) etc. are mentioned.

  Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium chloride salts, benzethonium chloride, pyridinium salts, and imidazolinium salts.

  Examples of amphoteric surfactants include carboxybetaine type, aminocarboxylate, imidazolinium betaine, lecithin, alkylamine oxide and the like.

The surfactant is preferably an anionic surfactant, more preferably a surfactant having a sulfo group. For example, dodecylbenzenesulfonic acid, a salt thereof, or the following general formula (W) A surfactant is preferably used.
Examples of the salt include ammonium salts (for example, salts with ammonia and triethanolamine), alkali metal salts (for example, lithium salts, sodium salts, potassium salts), halogens and the like. Of these, ammonium salts and potassium salts are particularly preferable.
However, when the substrate to be polished is a silicon substrate for a semiconductor integrated circuit or the like, contamination with an alkali metal, an alkaline earth metal, a halide, or the like is not desirable, so an acid or an ammonium salt thereof is desirable.

In the general formula (W), R represents a linear or branched alkyl group having 8 to 20 carbon atoms.
As this alkyl group, those having 10 to 20 carbon atoms are preferable, and those having 12 to 20 carbon atoms are more preferable. The alkyl group represented by R may be either linear or branched, but is preferably linear.
Specific examples of the alkyl group represented by R include a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, a hexadecyl group, a heptadecyl group, an octadecyl group, a nonadecyl group, and an eicosyl group. Among these, a dodecyl group, a tridecyl group, a tetradecyl group, a pentadecyl group, an octadecyl group, a nonadecyl group, and an eicosyl group are preferable.

In the general formula (W), Ar represents an aryl group. Examples of the aryl group represented by Ar include a phenyl group, a naphthyl group, an anthryl group, and a phenanthryl. Among them, a phenyl group is preferable.
In addition, several Ar which exists in general formula (W) may be same or different, and it is preferable that they are the same.

  The alkyl group or aryl group may further have a substituent. Examples of the substituent that can be introduced include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group (directly A chain, branched or cyclic alkyl group, which may be a polycyclic alkyl group such as a bicycloalkyl group or an active methine group), an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (substitute) Any position), acyl group, alkoxycarbonyl group, aryloxycarbonyl group, heterocyclic oxycarbonyl group, carbamoyl group (as the carbamoyl group having a substituent, for example, N-hydroxycarbamoyl group, N-acylcarbamoyl group, N-sulfonylcarbamoyl group, N-carbamoylcarbamoyl group, thiocarbamoyl group, N-sulfur Moylcarbamoyl group), carbazoyl group, carboxy group or a salt thereof, oxalyl group, oxamoyl group, cyano group, carbonimidoyl group, formyl group, hydroxy group, alkoxy group (a group repeatedly containing ethyleneoxy group or propyleneoxy group unit) Including), aryloxy group, heterocyclic oxy group, acyloxy group, (alkoxy or aryloxy) carbonyloxy group, carbamoyloxy group, sulfonyloxy group, amino group, (alkyl, aryl, or heterocyclic) amino group, acylamino group , Sulfonamide group, ureido group, thioureido group, N-hydroxyureido group, imide group, (alkoxy or aryloxy) carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, Razino group, ammonio group, oxamoylamino group, N- (alkyl or aryl) sulfonylureido group, N-acylureido group, N-acylsulfamoylamino group, hydroxyamino group, nitro group, quaternized nitrogen atom A heterocyclic group (eg, pyridinio group, imidazolio group, quinolinio group, isoquinolinio group), isocyano group, imino group, mercapto group, (alkyl, aryl, or heterocyclic ring) thio group, (alkyl, aryl, or heterocyclic ring) ) Dithio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group, sulfamoyl group (the sulfamoyl group having a substituent includes, for example, N-acylsulfamoyl group, N-sulfonylsulfa Moyl group), phosphino group, phosphinyl Group, phosphinyloxy group, phosphinylamino group, silyl group and the like, and an alkyl group and a sulfo group are preferable.

Further, in the general formula (W), M ⁺ represents a hydrogen ion, an alkali metal ion, or ammonium.
As an alkali metal ion represented by M ⁺ , a sodium ion and a potassium ion are preferable, and a sodium ion is more preferable.
In addition, ammonium (NH ₄ ⁺ ) represented by M ⁺ includes those in which the hydrogen atom of ammonium is substituted with an alkyl group. Examples thereof include methylammonium and ethylammonium.
M ⁺ is more preferably a hydrogen ion or ammonium, and particularly preferably a hydrogen ion.

  Specific examples of the surfactant represented by the general formula (W) include alkyls such as dodecyl diphenyl ether disulfonic acid, tetradecyl diphenyl ether disulfonic acid, hexadecyl diphenyl ether disulfonic acid, octadecyl diphenyl ether disulfonic acid, and eicosyl diphenyl ether disulfonic acid. Alkyl diphenyl ether monosulfonic acid such as diphenyl ether disulfonic acid and its salt, dodecyl diphenyl ether monosulfonic acid, tetradecyl diphenyl ether monosulfonic acid, hexadecyl diphenyl ether monosulfonic acid, octadecyl monophenyl ether disulfonic acid, eicosyl monophenyl ether disulfonic acid and the like Salt, dodecyl dinaphthyl ether disulfonic acid, dodecyl dianthryl ether Disulfonic acid, dodecyl dinaphthyl ether monosulfonic acid, dodecyl Jian tolyl ether monosulfonic acid, and their salts.

Among them, the surfactant represented by the general formula (W) preferably includes alkyl diphenyl ether disulfonic acid or a salt thereof from the viewpoint of reducing dishing, and also includes alkyl diphenyl ether disulfonic acid and alkyl diphenyl ether monosulfonic acid. Or a mixture of these salts.
In the case of the mixture as described above, the alkyldiphenyl ether monosulfonic acid is preferably contained in an amount of 10 mol% or more, more preferably 30 mol% or more, and further preferably 50 mol% or more.

  The surfactant represented by the general formula (W) is preferably contained in the metal polishing composition when used in an amount of 0.0001% by mass to 0.1% by mass, and 0.0005% by mass to 0%. More preferably, it is contained in an amount of 0.05% by mass, more preferably 0.001% by mass to 0.01% by mass.

  Only one surfactant may be used, or two or more surfactants may be used in combination. Moreover, the synthesis | combining method of surfactant represented by general formula (W) is not specifically limited, A commercial item can be used preferably.

<Hydrophilic polymer>
In the present invention, the following various hydrophilic polymers can be used in combination with the surfactant.

  Examples of hydrophilic polymers include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyethylene glycol alkyl ether, polyethylene glycol alkenyl ether, alkyl polyethylene glycol, alkyl polyethylene glycol alkyl ether, alkyl polyethylene glycol alkenyl ether, alkenyl polyethylene glycol, alkenyl polyethylene glycol. Alkyl ether, alkenyl polyethylene glycol alkenyl ether, polypropylene glycol alkyl ether, polypropylene glycol alkenyl ether, alkyl polypropylene glycol, alkyl polypropylene glycol alkyl ether, alkyl polypropylene glycol alkenyl ether Ethers such as tellurium, alkenyl polypropylene glycol, alkenyl polypropylene glycol alkyl ether and alkenyl polypropylene glycol alkenyl ether; polysaccharides such as alginic acid, pectic acid, carboxymethylcellulose, curdlan and pullulan; amino acid salts; polyaspartic acid, polyglutamic acid, polylysine; Polymalic acid, polymethacrylic acid, polymethacrylic acid ammonium salt, polymethacrylic acid sodium salt, polymaleic acid, polyitaconic acid, polyfumaric acid, poly (p-styrenecarboxylic acid), polyacrylic acid, polyacrylamide, aminopolyacrylamide, polyacrylic Acid ammonium salt, polyacrylic acid sodium salt, polyamic acid, polyamic acid ammonium salt, polyamic acid sodium Salt and poly Griot polycarboxylic acids and their salts such as hexyl acid; polyvinyl alcohol, vinyl polymers such as polyvinyl pyrrolidone and acrolein and the like.

  Of the above, the acid or its ammonium salt is preferably free from contamination by alkali metals, alkaline earth metals, halides and the like. Among the above exemplified compounds, cyclohexanol, polyacrylic acid ammonium salt, polyvinyl alcohol, succinic acid amide, polo vinyl pyrrolidone, polyethylene glycol, and polyoxyethylene polyoxypropylene block polymer are more preferable.

  The weight average molecular weight of these surfactants and hydrophilic polymers is preferably from 500 to 100,000, particularly preferably from 2,000 to 50,000.

The amount of the hydrophilic polymer added is preferably 0.0001% by mass to 1.0% by mass in the metal polishing composition when used as the total amount of the surfactant and the hydrophilic polymer. More preferably, 0.0005% by mass to 0.5% by mass is included, and 0.001% by mass to 0.1% by mass is further preferable.
In addition, a hydrophilic polymer may be used individually by 1 type, and may use 2 or more types together. Moreover, as a weight average molecular weight of these hydrophilic polymers, 500-100000 are preferable, and 2000-50000 are especially preferable.

[PH of metal polishing composition]
In the metal polishing composition of the present invention, depending on the reactivity and adsorption to the polishing surface, the solubility of the polishing metal, the electrochemical properties of the surface to be polished, the dissociation state of the compound functional group, the stability as a liquid, etc. It is preferable to appropriately set the kind of component, the amount added, or the pH.
The pH of the polishing composition of the present invention is preferably from 3 to 12, more preferably from 8.0 to 12.0 in terms of planarization performance. The pH can be easily adjusted by appropriately selecting and adding a buffering agent, an alkali agent and the like.

<Chemical mechanical polishing method>
In the chemical mechanical polishing method of the present invention, the metal polishing composition of the present invention is supplied to a polishing pad on a polishing surface plate, and the polishing surface plate is rotated so that the polishing pad is covered with an object to be polished. Polishing is performed by relative movement while being in contact with the polishing surface.
Hereinafter, this chemical mechanical polishing method will be described in detail.

(Polishing equipment)
First, an apparatus capable of carrying out the polishing method of the present invention will be described.
As a polishing apparatus applicable to the present invention, a holder for holding an object to be polished (semiconductor substrate or the like) having a surface to be polished and a polishing pad are attached (a motor or the like whose rotation speed can be changed is attached). A general polishing apparatus provided with a polishing surface plate can be used. For example, FREX300 (Ebara Seisakusho) can be used.

(Polishing pressure)
In the polishing method of the present invention, polishing is preferably performed at a polishing pressure, that is, a contact pressure between the surface to be polished and the polishing pad of 3000 to 25000 Pa, and more preferably 6500 to 14000 Pa.

(Number of rotations of polishing surface plate)
In the polishing method of the present invention, the polishing is preferably performed at a rotation speed of the polishing platen of 50 to 200 rpm, more preferably 60 to 150 rpm.

(Metal polishing composition supply method)
In the present invention, the metal polishing composition is continuously supplied to the polishing pad on the polishing surface plate with a pump or the like while the target metal is polished. Although there is no restriction | limiting in this supply amount, It is preferable that the surface of a polishing pad is always covered with the metal polishing composition.

  In the polishing method of the present invention, the concentrated metal polishing composition can be diluted with water or an aqueous solution. As a dilution method, for example, a pipe for supplying a concentrated metal polishing composition and a pipe for supplying water or an aqueous solution are joined together and mixed to mix the diluted metal polishing composition with a polishing pad. The method of supplying to can be mentioned. In this case, mixing is a method in which liquids collide with each other through a narrow passage with pressure applied, a method in which a filling such as a glass tube is filled in the piping, a flow of liquid is separated and separated, and piping is repeated. Conventional methods such as a method of providing blades that rotate with power can be used.

Further, as another dilution method, a pipe for supplying the metal polishing composition and a pipe for supplying water or an aqueous solution are provided independently, and a predetermined amount of liquid is supplied from each to the polishing pad, and the polishing pad and the coating are covered. A method of mixing by relative movement of the polishing surface can also be used in the present invention.
Furthermore, the present invention also includes a method in which a predetermined amount of a concentrated metal polishing composition and water or an aqueous solution are mixed in one container, mixed, diluted to a predetermined concentration, and then supplied to the polishing pad. Can be applied to.

  In addition to these methods, there is also a method for dividing the components to be contained in the metal polishing composition into at least two constituent components, and when using them, diluting them with water or an aqueous solution and supplying them to the polishing pad. Can be used for invention. In this case, it is preferable to divide and supply the component containing an oxidizing agent and the component containing the organic acid in the present invention.

  Specifically, the oxidizing agent is preferably one component (A), and the organic acid, additive, surfactant, heterocyclic compound, abrasive grains, and water are preferably one component (B). When using them, the component (A) and the component (B) are diluted with water or an aqueous solution. In this case, three pipes for supplying the component (A), the component (B), and water or an aqueous solution are necessary, and the three pipes are connected to one pipe for supplying the polishing pad, The two pipes may be combined and then another one pipe may be combined and mixed. For example, a composition for polishing metal is prepared by mixing a component containing an additive that is difficult to dissolve and other components, ensuring a dissolution time by lengthening a mixing path, and further connecting a pipe of water or an aqueous solution. It is also possible to supply

  Further, the above three pipes may be led to the polishing pad and mixed and supplied by the relative movement of the polishing pad and the surface to be polished. After mixing the three components in one container, the mixed solution is supplied. You may supply to a polishing pad. Further, the metal polishing composition may be used as a concentrate, and the diluted water may be separately supplied to the polishing surface.

(Supply amount of metal polishing composition)
In the polishing method of the present invention, the supply amount of the metal polishing composition onto the polishing platen is preferably 50 to 500 ml / min, and more preferably 100 to 300 ml / min.

(Polishing pad)
The polishing pad used in the polishing method of the present invention is not particularly limited, and may be a non-foamed structure pad or a foamed structure pad. The former uses a hard synthetic resin bulk material like a plastic plate for a pad. Further, the latter further includes three types of a closed foam (dry foam system), a continuous foam (wet foam system), and a two-layer composite (laminated system), and a two-layer composite (laminated system) is particularly preferable. Foaming may be uniform or non-uniform.

  The polishing pad in the present invention may further contain abrasive grains (for example, ceria, silica, alumina, resin, etc.) used for polishing. In addition, each has a softness and a hardness, and either of them may be used. In the laminated system, it is preferable to use a different hardness for each layer. The material is preferably non-woven fabric, artificial leather, polyamide, polyurethane, polyester, polycarbonate or the like. Further, the surface that contacts the polished surface may be subjected to processing such as lattice grooves / holes / concentric grooves / helical grooves.

  Next, an object to be polished (substrate, wafer) to be polished in the polishing method of the present invention will be described.

(Wiring metal material)
The object to be polished in the present invention is preferably a substrate (wafer) having wiring made of copper or a copper alloy. As the wiring metal material, a copper alloy containing silver is suitable among the copper alloys. The silver content contained in the copper alloy exhibits an excellent effect at 10% by mass or less, further 1% by mass or less, and the most excellent effect in the copper alloy in the range of 0.00001 to 0.1% by mass. Demonstrate.

(Wiring thickness)
In the DRAM device system, for example, the object to be polished in the present invention preferably has a wiring with a half pitch, preferably 0.15 μm or less, more preferably 0.10 μm or less, and further preferably 0.08 μm or less.
On the other hand, the MPU device system preferably has a wiring of preferably 0.12 μm or less, more preferably 0.09 μm or less, and still more preferably 0.07 μm or less.
The metal polishing composition used in the present invention exhibits a particularly excellent effect on the object to be polished having such wiring.

(Barrier metal material)
In the object to be polished in the present invention, a barrier layer for preventing copper diffusion is provided between the copper wiring and the insulating film (including the interlayer insulating film). As the barrier metal material constituting the barrier layer, a low-resistance metal material such as TiN, TiW, Ta, TaN, W, or WN is preferable, and Ta or TaN is particularly preferable.

  Hereinafter, the present invention will be described by way of examples. The present invention is not limited to these examples.

In addition, it shows below about the compound used in a following example and a comparative example.
APS: ammonium peroxodisulfate KPS: potassium peroxodisulfate KOH: potassium hydroxide Colloidal silica: “PL-3” manufactured by Fuso Chemical Industry Co., Ltd., primary particle size 35 nm
Colloidal silica: “PL-7” manufactured by Fuso Chemical Industry Co., Ltd., primary particle size: 70 nm
In addition, I-1, I-3, and II-1 shown in the column of Table 1 (a) heteroaromatic ring compound are shown above as specific examples of general formula (I) or general formula (II), respectively. These correspond to (I-1), (I-3), and (II-1), respectively.

[Example 1 to Example 10]
According to the following compositions and the following Table 1, metal polishing compositions A1 to A10 of Examples 1 to 10 were prepared.

-Preparation of metal polishing composition-
According to Table 1, the following composition was mixed in pure water to prepare each metal polishing composition.
-(A) Heteroaromatic ring compound: Compound shown in Table 1 ... 7 mmol / L
(B) Peroxodisulfate: compounds shown in Table 1 ... 1.0% by mass
-(C) Abrasive grains: Abrasive grains shown in Table 1 ... 0.5 mass%
(D) Organic acid: compounds shown in Table 1 ... 0.5% by mass
(E) Surfactant: Compound shown in Table 1 ... 0.05% by mass
The pH was adjusted to 9.5 using an appropriate amount of the pH adjusting agent shown in Table 1.

[Comparative Examples 1 to 5]
According to the following composition and the following Table 1, comparative polishing compositions B1 to B5 of Comparative Examples 1 to 5 were prepared.

-Preparation of metal polishing composition-
According to Table 1, the following composition was mixed in pure water to prepare a comparative polishing composition.
-(A) Heteroaromatic ring compound: compounds shown in Table 1 ... 7 mmol / L
(B) Peroxodisulfate or other oxidizing agent: compounds shown in Table 1
... 1.0% by mass
-(C) Abrasive grains: Abrasive grains shown in Table 1 ... 0.5 mass%
(D) Organic acid: compounds shown in Table 1 ... 0.5% by mass
(E) Surfactant: Compound shown in Table 1 ... 0.05% by mass
The pH was adjusted to 9.5 using an appropriate amount of the pH adjusting agent shown in Table 1.

  Metal polishing compositions (polishing liquids) A1 to A10 prepared in each of Examples 1 to 10 and Comparative polishing compositions (polishing liquids) B1 to B1 adjusted in Comparative Examples 1 to 5, respectively. Using B5, polishing was carried out by the following polishing method, and the polishing performance (copper film polishing rate, polishing rate uniformity and flatness) was evaluated. The evaluation results are shown in Table 1.

<Evaluation of polishing rate>
Using a device “FREX-300” manufactured by Ebara Manufacturing Co., Ltd. as a polishing apparatus, the film provided on each wafer is polished while supplying a slurry (a metal polishing composition or a comparative polishing composition) under the following conditions: The polishing rate was calculated.

Base: A 20 nm thick Ta film or Ti film (barrier film) is formed on a silicon oxide film by sputtering, and then a 50 nm thick copper film is formed as a wiring by sputtering, followed by plating. A 12 inch wafer with a 1000 nm thick copper film is used.
Table rotation speed: 65 rpm
-Head rotation speed: 64 rpm
・ Polishing pressure: 10.5kPa
Polishing pad: Product number IC-1400 (XY-K-grv) manufactured by Rohm and Haas
・ Slurry (metal polishing composition or comparative polishing composition) supply rate: 300 ml / min

The film thickness of the copper film was measured from the electrical resistance before and after polishing, and the polishing rate was calculated. Specifically, it calculated using the following formula.
Polishing rate (nm / min) = (thickness of copper film before polishing−thickness of copper film after polishing) / polishing time

<Evaluation of in-plane uniformity of polishing rate>
By the above method, the polishing rate was calculated for any 81 points on the long axis of the wafer surface. Using this calculation result, the in-plane uniformity of the polishing rate was calculated. Specifically, it calculated using the following formula. In-plane uniformity of polishing rate [%] = Standard deviation of polishing rate at 81 points / Average value of polishing rate Note that the smaller the value of the calculation result of in-plane uniformity of polishing rate, the better the in-plane uniformity. I can say that.

  As is clear from Table 1, the metal polishing compositions prepared in Examples 1 to 10 achieve a faster polishing rate than the comparative polishing compositions prepared in Comparative Examples 1 to 5. However, it can be seen that the in-plane uniformity of the polishing rate is improved. In addition, the metal polishing compositions prepared in Examples 1 to 10 have improved in-plane uniformity of the polishing rate compared to the comparative polishing compositions adjusted in Comparative Examples 1 to 5. Therefore, it can be said that the flatness is also good.

Claims (7)

(A) a heteroaromatic compound having a hydroxyl group as a substituent and a condensed 6-membered ring and a 5-membered ring containing a heteroatom, (b) peroxodisulfate, and (c) abrasive grains, and a semiconductor A metal polishing composition used for chemical mechanical polishing of a conductor film mainly composed of copper or a copper alloy in a device manufacturing process. The metal polishing composition according to claim 1, wherein the heteroaromatic ring compound is a compound represented by the following general formula (I) or the following general formula (II).

(In the above general formula (I), A represents a carbon atom or a nitrogen atom, X ¹ and Y each independently represent a hydrogen atom or a monovalent substituent, and at least one of X ¹ and Y is (In the general formula (II), X ² represents a hydroxyl group.)   Furthermore, (d) organic acid is included, The metal polishing composition of Claim 1 or Claim 2 characterized by the above-mentioned.   Furthermore, (e) surfactant is included, The metal polishing composition of any one of Claims 1-3 characterized by the above-mentioned. The metal polishing composition according to claim 4, wherein the surfactant (e) includes a surfactant represented by the following general formula (W).

(In the general formula (W), R represents a linear or branched alkyl group having 8 to 20 carbon atoms, Ar represents an aryl group, and M ⁺ represents a hydrogen ion, an alkali metal ion, or ammonium. .)   The said (c) abrasive grain is colloidal silica, The metal polishing composition of any one of Claims 1-5 characterized by the above-mentioned.   The metal polishing composition according to any one of claims 1 to 6 is supplied to a polishing pad on a polishing surface plate, and the polishing surface plate is rotated by rotating the polishing surface plate. A chemical mechanical polishing method in which polishing is performed by making a relative movement while being in contact with a surface to be polished.