JP2007081316A - Polishing liquid for metal and chemical mechanical polishing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing liquid for metal exhibiting a high CMP rate, and capable of fabricating an LSI while suppressing the occurrence of dishing to improve planarity, and to provide a chemical mechanical polishing method using the polishing liquid for metal. <P>SOLUTION: The polishing liquid for metal comprises at least one kind of compound expressed in a formula (I) and at least one kind of another chelating agent, or, the polishing liquid for metal comprises at least one kind of compound expressed in the formula (I), at least one kind of another chelating agent and an oxidant. In the polishing liquid for metal, the concentration of the oxidant is 1 wt.% or lower. The chemical mechanical polishing method comprises a step wherein the polishing liquid for metal is brought into contact with a to-be-polished surface, and then, by relatively moving the to-be-polished surface and a polishing surface, a substrate on which a metal wiring is formed is polished to remove at least a part of the metal. In the formula (I), Zs express atom groups forming five-membered or six-membered hetero rings, respectively. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to the manufacture of semiconductor devices, and more particularly to a metal polishing liquid in a wiring process of semiconductor devices and a chemical mechanical polishing method using the same.

  In the development of semiconductor devices represented by large-scale integrated circuits (hereinafter referred to as “LSI”), in recent years, miniaturization and stacking of wiring has led to higher density and higher integration for miniaturization and higher speed. It has been demanded. For this purpose, various techniques such as chemical mechanical polishing (hereinafter referred to as “CMP”) have been used. This CMP is an indispensable technique for surface flattening of processed films such as interlayer insulation films, plug formation, formation of embedded metal wiring, etc., and smoothing of the substrate and removal of excess metal thin film during wiring formation It is carried out. This technique is disclosed in Patent Document 1, for example.

A general method of CMP is to apply a polishing pad on a circular polishing platen (platen), immerse the surface of the polishing pad with a polishing liquid, press the surface of the substrate (wafer) against the pad, In a state where pressure (polishing pressure) is applied, both the polishing platen and the substrate are rotated, and the surface of the substrate is flattened by the generated mechanical friction.
The metal polishing liquid used for CMP generally contains abrasive grains (for example, alumina and silica) and an oxidizing agent (for example, hydrogen peroxide and persulfuric acid). The basic mechanism is considered to be that the metal surface is oxidized by an oxidizing agent and the oxide film is removed by abrasive grains, and is polished, for example, in Non-Patent Document 1.
However, when CMP is performed using a metal polishing liquid containing such solid abrasive grains, scratches (scratches), a phenomenon in which the entire polished surface is polished more than necessary (thinning), and the polished metal surface is dish-shaped. In some cases, a bending phenomenon (dishing), an insulator between metal wirings is polished more than necessary, and a plurality of wiring metal surfaces bend in a dish shape (erosion).
In addition, in the cleaning process usually performed to remove the polishing liquid remaining on the semiconductor surface after polishing, the use of the polishing liquid containing solid abrasive grains complicates the cleaning process, and further the liquid after the cleaning In order to treat (waste liquid), there is a problem in terms of cost, for example, it is necessary to settle and separate solid abrasive grains.

  As one means for solving these problems, for example, a metal surface polishing method using a combination of a polishing solution not containing abrasive grains and dry etching is disclosed in Non-Patent Document 2, and Patent Document 2 discloses hydrogen peroxide. Disclosed is a metal polishing slurry consisting of: / malic acid / benzotriazole / ammonium polyacrylate and water. According to these methods, the metal film on the convex portion of the semiconductor substrate is selectively CMPed, and the metal film is left in the concave portion to obtain a desired conductor pattern. Since CMP proceeds by friction with a polishing pad that is much mechanically softer than that containing conventional solid abrasive grains, the occurrence of scratches is reduced. However, there is a drawback that it is difficult to obtain a sufficient polishing rate due to a decrease in physical polishing power.

  On the other hand, tungsten and aluminum have conventionally 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 of wiring this copper, for example, a damascene method described in Patent Document 3 is known. Further, a dual damascene method in which a contact hole and a wiring trench 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 has been shipped. However, in recent years, with the miniaturization of wiring aiming at further higher density, it has become necessary to improve the conductivity and electronic characteristics of copper wiring, and accordingly, a copper alloy in which a third component is added to high-purity copper is required. It is also beginning to be considered for use. At the same time, there is a need for high-speed metal polishing means that can exhibit high productivity without contaminating these high-definition and high-purity materials. In the polishing of copper metal, since it is a particularly soft metal, the above-mentioned dishing, erosion, and scratches are likely to occur, and a highly accurate polishing technique is increasingly required.

Furthermore, in order to improve productivity, the diameter of wafers at the time of manufacturing LSIs has been increasing, and nowadays, diameters of 200 mm or more are widely used, and manufacturing with a size of 300 mm or more has started. As the size of the wafer increases, the difference in polishing rate between the wafer central portion and the peripheral portion is likely to occur, and the demand for uniformity of polishing within the wafer surface is becoming increasingly severe.
As a chemical polishing method having no mechanical polishing means for copper and copper alloys, a method described in Patent Document 4 is known. However, the chemical polishing method using only the chemical dissolution action has a greater problem in flatness due to the occurrence of dishing of the recess, that is, the occurrence of dishing, as compared with CMP in which the metal film of the protrusion is selectively chemically and mechanically polished. Remaining.

  Further, when copper wiring is used, a diffusion preventing 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, which includes TaN, TaSiN, It is made of one or more layers selected from Ta, TiN, Ti, Nb, W, WN, Co, Ru, Zr, ZrN, and CuTa alloy. However, since these barrier materials themselves have conductive properties, the barrier material on the insulating layer must be completely removed to prevent the occurrence of errors such as leakage current. This is achieved by a method similar to bulk polishing (barrier CMP). Since dishing is likely to occur particularly in a wide metal wiring portion in bulk polishing of copper, it is desirable that the amount of polishing and removal in the wiring portion and the barrier portion can be adjusted in order to achieve final planarization. For this reason, it is desired that the polishing liquid for barrier polishing has an optimum copper / barrier metal polishing selectivity. 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.

US Pat. No. 4,944,836 JP 2001-127019 A JP-A-2-278822 JP 49-122432 A Journal of Electrochemical Society, 1991, 138, 11, 3460-3464 Journal of Electrochemical Society, 2000, 147, 10, 3907-3913

In the present invention, in order to increase the productivity of LSIs in order to proceed with a quicker CMP, it is required to increase the polishing rate of such wiring made of copper metal and copper alloy as raw materials. This is based on the background.
Accordingly, an object of the present invention is to provide a metal polishing liquid that has a rapid CMP rate, has less dishing, improves flatness, and enables the fabrication of LSI, and a chemical mechanical using the metal polishing liquid. It is to provide a polishing method.

As a result of intensive studies on the problems associated with the above-described metal polishing liquid, the present inventors have found that the problem can be solved by using the following metal polishing liquid, and have achieved the object.
That is, the present invention is as shown in the following <1> and <6>. It is shown below with <2>-<5> which are preferable embodiments.
<1> A metal polishing slurry comprising at least one compound represented by the following formula (I) and at least one other chelating agent:

（式（I）中、Ｚはそれぞれ独立に、５員又は６員環を形成する原子団を表す。）
＜２＞ 下記式（I）で表される化合物の少なくとも１種と、それ以外のキレート剤の少なくとも１種と、酸化剤とを含有する金属用研磨液であって、酸化剤の濃度が１重量％以下であることを特徴とする金属用研磨液、

(In formula (I), each Z independently represents an atomic group that forms a 5- or 6-membered ring.)
<2> A metal-polishing liquid containing at least one compound represented by the following formula (I), at least one other chelating agent, and an oxidizing agent, wherein the concentration of the oxidizing agent is 1 Metal polishing liquid, characterized in that it is not more than% by weight,

（式（I）中、Ｚはそれぞれ独立に、５員又は６員環を形成する原子団を表す。）
＜３＞ 酸化剤として過酸化水素又は過硫酸塩を用いる上記＜２＞に記載の金属用研磨液、
＜４＞ 式（I）で表される化合物の総添加量が、該キレート剤の総添加量に対して、モル比で０．０００５〜０．１である上記＜１＞〜＜３＞のいずれか１つに記載の金属用研磨液、
＜５＞ 該キレート剤が、アミノ酸又はアミノポリカルボン酸である上記＜１＞〜＜４＞のいずれか１つに記載の金属用研磨液、
＜６＞ 上記＜１＞〜＜５＞のいずれか１つに記載の金属用研磨液を、被研磨面と接触させ、被研磨面と研磨面を相対運動させて、金属配線を形成した基板を研磨することにより金属の少なくとも一部を除去する工程を含むことを特徴とする化学機械的研磨方法。

(In formula (I), each Z independently represents an atomic group that forms a 5- or 6-membered ring.)
<3> The metal polishing slurry according to <2>, wherein hydrogen peroxide or persulfate is used as the oxidizing agent.
<4> The total addition amount of the compound represented by the formula (I) is 0.0005 to 0.1 in terms of molar ratio with respect to the total addition amount of the chelating agent. The metal polishing liquid according to any one of the above,
<5> The metal polishing slurry according to any one of <1> to <4>, wherein the chelating agent is an amino acid or an aminopolycarboxylic acid,
<6> Substrate on which metal wiring is formed by bringing the metal polishing liquid according to any one of <1> to <5> above into contact with a surface to be polished and causing the surface to be polished and the polishing surface to move relative to each other. A chemical mechanical polishing method comprising a step of removing at least a part of a metal by polishing the metal.

  According to the present invention, it is possible to obtain a metal polishing liquid having a rapid CMP rate, less dishing and improved flatness. Further, according to the present invention, a chemical mechanical polishing method excellent in polishing rate, corrosion, and in-plane uniformity can be performed.

Hereinafter, specific embodiments of the present invention will be described.
In addition, in the description of group (atomic group) in this specification, the description which does not describe substitution and non-substitution includes what has a substituent with what does not have a substituent. For example, the “alkyl group” includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).

<Metal polishing liquid>
The metal polishing liquid of the present invention (hereinafter also simply referred to as “polishing liquid”) includes at least a compound represented by the following formula (I) and a chelating agent other than the compound represented by the formula (I) as constituent components. In general, it is an aqueous solution, and preferably contains an amino acid or aminopolycarboxylic acid as the chelating agent.
The polishing liquid of the present invention may further contain other components, and preferred components include surfactants, water-soluble polymers, abrasive grains, and additives.
Each component contained in the polishing liquid may be used alone or in combination of two or more.

Of the components added during the preparation of the concentrated liquid of the polishing liquid, the blending amount of water having a solubility in water of less than 5% at room temperature is room temperature in order to prevent precipitation when the concentrated liquid is cooled to 5 ° C or the like. The solubility in water is preferably within 2 times, more preferably within 1.5 times.
In this specification, “concentration” and “concentrated liquid” are used in accordance with conventional expressions meaning “thick” and “thick liquid” rather than the state of use, and physical concentration operations such as evaporation are performed. It is used in a different way from the meaning of the general terms involved.

That is, the concentrated liquid or the concentrated polishing liquid means a polishing liquid prepared with a higher solute concentration than the polishing liquid used for polishing, and when used for polishing, It is diluted and used for polishing. The dilution factor is generally 1 to 20 volume times.
In the present invention, the “polishing liquid” means not only a polishing liquid used for polishing (that is, a polishing liquid diluted as necessary) but also a concentrated liquid of the polishing liquid.

Hereinafter, each component will be described.
(Compound represented by formula (I))

（式（I）中、Ｚはそれぞれ独立に、５員又は６員環を形成する原子団を表す。）

(In formula (I), each Z independently represents an atomic group that forms a 5- or 6-membered ring.)

First, the compound represented by formula (I) will be described in detail below.
In the formula (I), Z represents an atomic group containing at least one atom selected from the group consisting of a carbon atom, a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom. 5-membered or 6-membered heterocycles are formed. The 5-membered or 6-membered heterocycle may or may not contain a double bond in the ring structure, and may be an aromatic heterocycle. Two Zs may be the same or different independently.
The heterocycle is preferably a 5-membered or 6-membered heterocycle whose ring member is constituted by a carbon atom and a nitrogen atom, and more preferably, the two heterocycles of the formula (I) are both 6-membered. is there. The heterocycle may have a substituent, and each ring may be connected by a substituent to form a new ring. Although it does not specifically limit as a substituent, For example, the following are mentioned.

Halogen atom (fluorine atom, chlorine atom, bromine atom or iodine atom), alkyl group (straight chain, branched or cyclic alkyl group, and active methine even if it is a polycyclic alkyl group such as a bicycloalkyl group) An alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (regardless of the position of substitution), an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a heterocyclic oxycarbonyl group, a carbamoyl group (substituted) Examples of the carbamoyl group having a group include N-hydroxycarbamoyl group, N-acylcarbamoyl group, N-sulfocarbamoyl group, N-carbamoylcarbamoyl group, thiocarbamoyl group, N-sulfamoylcarbamoyl group), carbazoyl group, carboxy Group or a salt thereof, oxalyl group, oxamoyl group A cyano group, a carbonimidoyl group (Carbonimidoyl group), a formyl group, a hydroxy group, an alkoxy group (including a group containing repeating ethyleneoxy group or propyleneoxy group units), an aryloxy group, a heterocyclic oxy group, an acyloxy group, Alkoxy or aryloxy) carbonyloxy group, carbamoyloxy group, sulfonyloxy group, amino group, (alkyl, aryl, or heterocyclic) amino group, acylamino group, sulfonamido group, ureido group, thioureido group, N-hydroxyureido group Imide group, (alkoxy or aryloxy) carbonylamino group, sulfamoylamino group, semicarbazide group, thiosemicarbazide group, hydrazino group, ammonio group, oxamoylamino group, N- (alkoxy) Or aryl) sulfonylureido group, N-acylureido group, N-acylsulfamoylamino group, hydroxyamino group, nitro group, heterocyclic group containing a quaternized nitrogen atom (eg, pyridinio group, imidazolio group, quinolinio group) , Isoquinolinio group), isocyano group, imino group, mercapto group, (alkyl, aryl, or heterocyclic) thio group, (alkyl, aryl, or heterocyclic) dithio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) ) Sulfinyl group, sulfo group or a salt thereof, sulfamoyl group (for example, N-acylsulfamoyl group or N-sulfonylsulfamoyl group as a substituted sulfamoyl group) or a salt thereof, phosphino group, phosphinyl group, phos Finyloxy group, Phosphi Nylamino group, silyl group, alkylidene group, oxo group and the like can be mentioned.
These substituents may be further substituted with the above substituents. Further, the substituent is preferably a water-soluble substituent, and particularly preferably a hydroxy group, a sulfo group, or a carboxy group. Two or more substituents may be bonded to form a ring.

  Among the compounds represented by the formula (I), the compounds represented by the formulas (II) to (IV) are preferable, and the compound represented by the following formula (II) or the formula (III) is more preferable. Particularly preferred is a compound represented by the formula (II).

（式（II）中、Ｒ¹は置換基を表し、ｎ_aは０〜４の整数を表す。）

(In formula (II), R ¹ represents a substituent, and n _a represents an integer of 0 to 4.)

（式（III）中、Ｒ²は置換基を表し、ｎ_bは０〜３の整数を表し、ｎ_cは０〜２の整数を表す。）

(In the formula (III), R ² is a substituted group, n _b represents an integer of 0 to 3, n _c is an integer of 0 to 2.)

（式（IV）中、Ｒ³は置換基を表し、ｎ_dは０〜２の整数を表す。）

(In formula (IV), R ³ represents a substituent, and n _d represents an integer of 0 to 2.)

As the substituents represented by R ₁ , R ₂ and R ₃ , those exemplified as the substituents which the heterocyclic ring formed by Z in formula (I) may have are applicable. The preferable range is also the same. When there are two or more R ¹ , R ² or R ³ , the plurality of R ₁ , R ₂ and R ₃ may be the same or different from each other.
n _a represents an integer of 0 to 4, preferably 0 or 1.
n _b represents an integer of 0 to 3, and is preferably 0 or 1.
n _c represents an integer of 0 to 2, and is preferably 0 or 1.
n _d represents an integer of 0 to 2, and is preferably 0 or 1.

Preferred specific examples (I-1) to (I-32) of the compound represented by the formula (I) are listed below, but are not limited thereto. The following (I-24) and (I-26) represent that two SO ₃ H groups are substituted at any position in the atomic group Z.

  The compound represented by the formula (I) can be synthesized by a known method, but a commercially available product may be used.

  Moreover, in this invention, the total addition amount of the compound represented by the said formula (I) is 0.00 with respect to 1 mol of total addition amounts of chelating agents other than the compound represented by the formula (I) mentioned later. It is preferably from 00005 to 0.5 mol, more preferably from 0.0001 to 0.3 mol, and particularly preferably from 0.0005 to 0.1 mol.

  The metal polishing slurry of the present invention contains a chelating agent other than the compound represented by the formula (I) and the compound represented by the formula (I) described later. The reason why the polishing performance is improved compared to using these alone is not necessarily elucidated, but there is probably a synergistic effect on the chemical reaction on the metal surface and the performance of the compound formed on the metal surface. It is thought that it is because.

(Chelating agent)
In the present invention, at least one chelating agent other than the compound represented by the formula (I) (hereinafter also simply referred to as “chelating agent”) is contained.
As a chelating agent that can be used in the present invention, a metal salt compound or a complex salt is formed with respect to the metal ions in order to reduce adverse effects such as metal ions mixed during polishing liquid preparation or polishing, especially polyvalent metal ions. As long as it is a compound or a compound that forms a metal complex by coordination to a metal ion, it can be used without particular limitation. For example, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid that are polycarboxylic acids , Pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid, polyphosphonic acid N, N, N-trimethylenephosphonic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, polysulfonic acid 1,2-dihydroxybenzene-4,6-disulfonic acid, or an amino acid or aminopolycarboxylic acid is preferred, Aminopolycarboxylic acids of an amino acid or water-soluble soluble are particularly preferred.

The amino acid that can be used in the present invention may have a substituent, and in particular, those selected from the following group are more suitable.
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-diodo-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, L Asparagine, L-glutamine, azaserine, L-arginine, L-canavanine, L-citrulline, δ-hydroxy-L-lysine, creatine, L-quinurenin, L-histidine, 1-methyl-L-histidine, 3-methyl -Amino acids such as L-histidine, ergothionein, L-tryptophan, actinomycin C1, apamin, angiotensin I, angiotensin II and antipine.
Among these, glycine, L-alanine, L-histidine, L-proline, L-lysine, and dihydroxyethylglycine are particularly preferable.

  Examples of the aminopolycarboxylic acid include iminodiacetic acid, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, N, N, N-trimethylenephosphonic acid, ethylenediamine-N, N, N ′, N′-tetra Methylenesulfonic acid, transcyclohexanediaminetetraacetic acid, 1,2-diaminopropanetetraacetic acid, glycol ether diaminetetraacetic acid, ethylenediamine orthohydroxyphenylacetic acid, ethylenediamine disuccinic acid (SS form), N- (2-carboxylate ethyl)- Examples include L-aspartic acid, β-alanine diacetate, 2-phosphonobutane-1,2,4-tricarboxylic acid, N, N′-bis (2-hydroxybenzyl) ethylenediamine-N, N′-diacetic acid.

  The chelating agent that can be used in the present invention is particularly preferably a compound represented by the following formula (1) or formula (2).

R ₁ in Formula (1) represents a single bond, an alkylene group, or a phenylene group.
R ₂ and R ₃ in Formula (1) each independently represent a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group.
R ₄ and R ₅ in Formula (1) each independently represent a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, or an acyl group.
However, when R ₁ is a single bond, at least one of R ₄ and R ₅ is not a hydrogen atom.

The alkylene group as R ₁ in Formula (1) may be linear, branched or cyclic, and preferably has 1 to 8 carbon atoms, and examples thereof include a methylene group and an ethylene group. it can.
Examples of the substituent that the alkylene group may have include a hydroxyl group and a halogen atom.

The alkyl group as R ₂ and R ₃ in Formula (1) preferably has 1 to 8 carbon atoms, and examples thereof include a methyl group and a propyl group.
The cycloalkyl group as R ₂ and R ₃ in Formula (1) preferably has 5 to 15 carbon atoms, and examples thereof include a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.
The alkenyl group as R ₂ and R ₃ in Formula (1) preferably has 2 to 9 carbon atoms, and examples thereof include a vinyl group, a propenyl group, and an allyl group.
The alkynyl group as R ₂ and R ₃ in Formula (1) preferably has 2 to 9 carbon atoms, and examples thereof include an ethynyl group, a propynyl group, and a butynyl group.

The aryl group as R ₂ and R ₃ in Formula (1) preferably has 6 to 15 carbon atoms, and examples thereof include a phenyl group.
The alkylene chain in these groups may have a hetero atom such as an oxygen atom or a sulfur atom.
As each group substituents which may have as R ₂ and R ₃ in the formula (1), hydroxyl group, a halogen atom, an aromatic ring (preferably having from 3 to 15 carbon atoms), a carboxyl group, an amino group, etc. be able to.

The alkyl group as R ₄ and R ₅ in Formula (1) preferably has 1 to 8 carbon atoms, and examples thereof include a methyl group and an ethyl group.
The acyl group preferably has 2 to 9 carbon atoms, and examples thereof include a methylcarbonyl group.
Examples of the substituent that each group represented by R ₄ and R ₅ in Formula (1) may have include a hydroxyl group, an amino group, and a halogen atom.

In formula (1), it is preferable that either one of R ₄ and R ₅ is not a hydrogen atom.
In formula (1), it is particularly preferred that R ₁ is a single bond, and R ₂ and R ₄ are hydrogen atoms. In this case, R ₃ represents a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group, and particularly preferably a hydrogen atom or an alkyl group. R ₅ represents a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, or an acyl group, and an alkyl group is particularly preferable. As the substituent that the alkyl group as R ₃ may have, a hydroxyl group, a carboxyl group, or an amino group is preferable. As the substituent that the alkyl group as R ₅ may have, a hydroxyl group or an amino group is preferable.

R ₆ in Formula (2) represents a single bond, an alkylene group, or a phenylene group.
R ₇ and R ₈ in Formula (2) each independently represents a hydrogen atom, a halogen atom, a carboxyl group, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group, or an aryl group.
R ₉ in formula (2) represents a hydrogen atom, a halogen atom, a carboxyl group, or an alkyl group.
R ₁₀ in the formula (2) represents an alkylene group.
However, when R ₁₀ is —CH ₂ —, R ₆ is not a single bond, or at least R ₉ is not a hydrogen atom.

The alkylene group as R ₆ and R ₁₀ in formula (2) may be linear, branched or cyclic, and preferably has 1 to 8 carbon atoms. For example, a methylene group or an ethylene group Can be mentioned.
Examples of the substituent that the alkylene group and phenylene group may have include a hydroxyl group and a halogen atom.

The alkyl group as R ₇ and R ₈ in Formula (2) preferably has 1 to 8 carbon atoms, and examples thereof include a methyl group and a propyl group.
The cycloalkyl group as R ₇ and R ₈ in Formula (2) preferably has 5 to 15 carbon atoms, and examples thereof include a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.
The alkenyl group as R ₇ and R ₈ in Formula (2) preferably has 2 to 9 carbon atoms, and examples thereof include a vinyl group, a propenyl group, and an allyl group.
The alkynyl group as R ₇ and R ₈ in Formula (2) preferably has 2 to 9 carbon atoms, and examples thereof include an ethynyl group, a propynyl group, and a butynyl group.

The aryl group as R ₇ and R ₈ in formula (2) preferably has 6 to 15 carbon atoms, and examples thereof include a phenyl group.
The alkylene chain in these groups may have a hetero atom such as an oxygen atom or a sulfur atom.
Examples of the substituent that each group represented by R ₇ and R ₈ in Formula (2) may have include a hydroxyl group, a halogen atom, and an aromatic ring (preferably having 3 to 15 carbon atoms).

The alkyl group as R ₉ in Formula (2) preferably has 1 to 8 carbon atoms, and examples thereof include a methyl group and an ethyl group.
The acyl group as R ₉ in Formula (2) preferably has 2 to 9 carbon atoms, and examples thereof include a methylcarbonyl group.
The alkylene chain in these groups may have a hetero atom such as an oxygen atom or a sulfur atom.
Examples of the substituent that each group as R ₉ in Formula (2) may have include a hydroxyl group, an amino group, a halogen atom, and a carboxyl group.
In formula (2), R ₉ is preferably not a hydrogen atom.

  Although the preferable specific example of a compound represented by Formula (1) or Formula (2) below is given, it does not limit to these.

  There is no restriction | limiting in particular as a synthesis method of the compound represented by Formula (1) or (2), It can synthesize | combine by a well-known method. A commercially available compound may be used as the compound represented by the formula (1) or (2).

  The total amount of the chelating agent other than the compound represented by formula (I) is the polishing liquid used for polishing (that is, the diluted polishing liquid when diluted with water or an aqueous solution. In 1 liter of “the polishing liquid when used in the present invention” is preferably 0.0001 to 3 mol, more preferably 0.005 to 1 mol, and more preferably 0.01 to 0.5 mol. It is particularly preferred.

Further, thiocyanate, thioethers, thiosulfate or meso ion compound may be used in combination with an addition amount smaller than the total addition amount of the chelate compound.
The thiocyanate that can be used in the present invention is preferably the thiocyanate described in JP-A-2004-235319, and the thioether is preferably the thioether described in JP-A-2004-235318. As the thiosulfate, the thiosulfate described in JP-A-2004-235326 can be preferably mentioned, and as the mesoionic compound, the mesoionic compound described in JP-A-2004-235320 is preferable. Can be mentioned.

(Oxidant)
The polishing liquid of the present invention preferably contains a compound (oxidant) that can oxidize the metal to be polished. Examples of the oxidizing agent include hydrogen peroxide, peroxide, nitrate, iodate, periodate, hypochlorite, chlorite, chlorate, perchlorate, persulfate, Examples include dichromate, permanganate, ozone water, silver (II) salt, and iron (III) salt.
Examples of iron (III) salts include inorganic iron (III) salts such as iron nitrate (III), iron chloride (III), iron sulfate (III), iron bromide (III), and organic iron (III) salts. Complex salts are preferably used.

  When an organic complex salt of iron (III) is used, examples of complex-forming compounds constituting the iron (III) complex salt include acetic acid, citric acid, oxalic acid, salicylic acid, diethyldithiocarbamic acid, succinic acid, tartaric acid, glycolic acid, glycine , Alanine, aspartic acid, thioglycolic acid, ethylenediamine, trimethylenediamine, diethylene glycol, triethylene glycol, 1,2-ethanedithiol, malonic acid, glutaric acid, 3-hydroxybutyric acid, propionic acid, phthalic acid, isophthalic acid, 3 Aminopolycarboxylic acid and its salt are mentioned other than -hydroxy salicylic acid, 3,5-dihydroxy salicylic acid, gallic acid, benzoic acid, maleic acid, etc. and these salts.

  Examples of aminopolycarboxylic acids and salts thereof include ethylenediamine-N, N, N ′, N′-tetraacetic acid, diethylenetriaminepentaacetic acid, 1,3-diaminopropane-N, N, N ′, N′-tetraacetic acid, , 2-Diaminopropane-N, N, N ′, N′-tetraacetic acid, ethylenediamine-N, N′-disuccinic acid (racemic), ethylenediamine disuccinic acid (SS), N- (2-carboxylate ethyl) ) -L-aspartic acid, N- (carboxymethyl) -L-aspartic acid, β-alanine diacetic acid, methyliminodiacetic acid, nitrilotriacetic acid, cyclohexanediaminetetraacetic acid, iminodiacetic acid, glycol etherdiaminetetraacetic acid, ethylenediamine-N, N '-Diacetic acid, ethylenediamine orthohydroxyphenylacetic acid, N, N-bis (2-hydroxybenzyl) Ethylenediamine -N, include and salts thereof such as N- diacetic acid. The kind of the counter salt is preferably an alkali metal salt or an ammonium salt, and particularly preferably an ammonium salt.

Of these, organic complex salts of hydrogen peroxide, iodate, hypochlorite, chlorate, and iron (III) are preferred, and preferred complex-forming compounds when using an organic complex salt of iron (III) are Acid, tartaric acid, aminopolycarboxylic acid (specifically, ethylenediamine-N, N, N ′, N′-tetraacetic acid, diethylenetriaminepentaacetic acid, 1,3-diaminopropane-N, N, N ′, N′- Tetraacetic acid, ethylenediamine-N, N'-disuccinic acid (racemic), ethylenediaminedisuccinic acid (SS), N- (2-carboxylateethyl) -L-aspartic acid, N- (carboxymethyl) -L- Aspartic acid, β-alanine diacetic acid, methyliminodiacetic acid, nitrilotriacetic acid, iminodiacetic acid).
Among the oxidizing agents, hydrogen peroxide and iron (III) ethylenediamine-N, N, N ′, N′-tetraacetic acid, 1,3-diaminopropane-N, N, N ′, N′-tetraacetic acid and ethylenediaminedi A succinic acid (SS body) complex is most preferable.

As a density | concentration of the oxidizing agent in the metal polishing liquid of this invention, it is preferable that it is 1 weight% or less, and it is more preferable that it is 0.5 weight%.
Moreover, the addition amount of the oxidizing agent is preferably 0.003 mol to 8 mol, more preferably 0.03 mol to 6 mol, and more preferably 0.1 mol to 4 mol in 1 L of the polishing liquid used for polishing. It is particularly preferable to do this. That is, the addition amount of the oxidizing agent is preferably 0.003 mol or more from the viewpoint of sufficient metal oxidation and ensuring a high CMP rate, and is preferably 8 mol or less from the viewpoint of preventing roughening of the polished surface.

(acid)
The polishing liquid of the present invention preferably further contains an acid. The acid here is a compound having a structure different from that of the oxidizing agent for oxidizing the metal, and does not include an acid that functions as the above-mentioned oxidizing agent. The acid here has an action of promoting oxidation, adjusting pH, and buffering agent.
Examples of the acid include inorganic acids and organic acids within the range.
Examples of the inorganic acid include sulfuric acid, nitric acid, boric acid, phosphoric acid, and among the inorganic acids, phosphoric acid and nitric acid are preferable.
The organic acid is preferably water-soluble. Those selected from the following group are more suitable. 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-methylhexanoic acid , N-octanoic acid, 2-ethylhexanoic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid lactic acid, and salts thereof such as ammonium salts and alkali metal salts, sulfuric acid, nitric acid, ammonia, ammonium salts, or mixtures thereof Etc. Of these, formic acid, acetic acid and glycolic acid are preferred.

(Heterocyclic compound)
In the present invention, in addition to the compound represented by the formula (I), a heterocyclic compound may be contained.
The heterocyclic compound that can be used in the present invention is preferably a compound having a 5-membered ring or a 6-membered ring. For example, imidazole, pyrazole, thiazole, pyridine, oxazole, pyrrole, triazole, tetrazole, benzotriazole, methylbenzotriazole , Purine, quinoline, tolyltriazole and the like and derivatives thereof. In the present invention, among these, a compound having a nitrogen-containing heterocyclic ring is preferable, and among them, a compound represented by the following formula (V) or formula (VI) is particularly preferable.
First, the compound represented by formula (V) will be described in detail below.

In formula (V), R ¹ and R ² each independently represent a hydrogen atom or a monovalent substituent. R ¹ and R ² may be bonded to each other to form a ring. When R ¹ and R ² are simultaneously hydrogen atoms, the compound represented by the formula (V) may be a tautomer thereof.

Although the monovalent substituent as R < ¹ > and R < ² > in Formula (V) is not specifically limited, For example, the following are mentioned. However, in R ^1, among the monovalent substituents described below, when combined with the nitrogen atom, the compound is not included the monovalent substituent which is not stably obtained.

  Halogen atom (fluorine atom, chlorine atom, bromine atom or iodine atom), alkyl group (straight chain, branched or cyclic alkyl group, and active methine group even if it is a polycyclic alkyl group such as a bicycloalkyl group) ), Alkenyl group, alkynyl group, aryl group, heterocyclic group (regarding the position of substitution), acyl group, alkoxycarbonyl group, aryloxycarbonyl group, heterocyclic oxycarbonyl group, carbamoyl group (substituent) For example, N-hydroxycarbamoyl group, N-acylcarbamoyl group, N-sulfonylcarbamoyl group, N-carbamoylcarbamoyl group, thiocarbamoyl group, N-sulfamoylcarbamoyl group), carbazoyl group, carboxy Group or a salt thereof, oxalyl group, oxamoyl group A cyano group, a carbonimidoyl group (Carbonimidoyl group), a formyl group, a hydroxy group, an alkoxy group (including a group containing repeating ethyleneoxy group or propyleneoxy group units), an aryloxy group, a heterocyclic oxy group, an acyloxy group, ( (Alkoxy or aryloxy) carbonyloxy group, (unsubstituted, mono- or disubstituted) carbamoyloxy group, (unsubstituted, alkyl or aryl) 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, sulfamoyl Amino group, semicarbazide group, thiosemicarbazide group, hydrazino group, ammonio group, oxamoylamino group, N- (alkyl or aryl) sulfonylureido group, N-acylureido group, N-acylsulfamoylamino group, hydroxyamino group, A nitro group, a heterocyclic group containing a quaternized nitrogen atom (eg, pyridinio group, imidazolio group, quinolinio group, isoquinolinio group), isocyano group, imino group, mercapto group, (alkyl, aryl, or heterocyclic) thio group , (Alkyl, Reel, or heterocycle) dithio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or a salt thereof, sulfamoyl group (substituted sulfamoyl group, for example, N-acyl sulfa Moyl group, N-sulfonylsulfamoyl group) or a salt thereof, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, silyl group and the like.

  The active methine group means a methine group substituted with two electron-withdrawing groups. Examples of the electron-withdrawing group include an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, and an alkyl group. A sulfonyl group, an arylsulfonyl group, a sulfamoyl group, a trifluoromethyl group, a cyano group, a nitro group, and a carbonimidoyl group (Carbonimidoyl group) are meant. Two electron withdrawing groups may be bonded to each other to form a cyclic structure. The salt means a cation such as alkali metal, alkaline earth metal or heavy metal, or an organic cation such as ammonium ion or phosphonium ion.

  Among these, preferable monovalent substituents include, for example, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group (a linear, branched or cyclic alkyl group, and a bicycloalkyl group). A polycyclic alkyl group or an active methine group), an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (regardless of the position of substitution), an acyl group, an alkoxycarbonyl group, an aryloxy group Carbonyl group, heterocyclic oxycarbonyl group, carbamoyl group, N-hydroxycarbamoyl group, N-acylcarbamoyl group, N-sulfonylcarbamoyl group, N-carbamoylcarbamoyl group, thiocarbamoyl group, N-sulfamoylcarbamoyl group, carbazoyl group , Oxalyl group, oxamoyl group, cyano group, carvone Midyl group (Carbonimidoyl group), formyl group, hydroxy group, alkoxy group (including groups containing repeating ethyleneoxy group or propyleneoxy group units), aryloxy group, heterocyclic oxy group, acyloxy group, (alkoxy or aryloxy) Carbonyloxy group, (unsubstituted, monosubstituted or disubstituted) carbamoyloxy group, (unsubstituted, alkyl or aryl) 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, hydrazino group, ammonio group, oxamoylamino group, N- (alkyl or aryl) sulfonylureido group, N-acylureido group, N-acylsulfamoylamino group, hydroxyamino group, nitro group, quaternized heterocyclic group containing nitrogen atom (for example, pyridinio group, imidazolio group, quinolinio group, isoquinolinio group), isocyano group, imino group, mercapto Group, (alkyl, aryl, or heterocyclic) thio group, (alkyl, aryl, or heterocyclic) dithio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or salt thereof, sulfamoyl group , N- Sils sulfamoyl group, N- sulfonylsulfamoyl group or a salt thereof, a phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, a silyl group.

  More preferably, for example, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group (a linear, branched or cyclic alkyl group, and a polycyclic alkyl group such as a bicycloalkyl group). Or an active methine group), an alkenyl group, an alkynyl group, an aryl group, an amino group, and a heterocyclic group (regarding the position of substitution).

The ring formed by combining R ¹ and R ² in formula (V) together with the —C—N— bond may be monocyclic or polycyclic, preferably a 5- to 6-membered ring. Or a polycyclic ring composed of a 5- to 6-membered ring.
The monovalent substituent may be further substituted with the monovalent substituent.

In addition, the compound represented by the formula (V) that can be used in the present invention may be, for example, a compound forming a salt such as hydrochloride or carboxylate.
The molecular weight of the compound represented by the formula (V) is preferably 70 to 600, more preferably 70 to 400.

  Specific examples of the compound represented by the formula (V) are shown below, but are not limited thereto.

  Among the compounds represented by the formula (V), compounds V-1, V-3, V-4, V-10, V-15, V-21, V-22, V-23, V-41 and V-48 may be mentioned, and compounds V-1, V-4, V-15, V-22 and V-23 are more preferable.

Moreover, the compound represented by Formula (V) may be used independently and may be used together 2 or more types.
The compound represented by the formula (V) can be synthesized according to a conventional method, or a commercially available product may be used.

  Next, the compound represented by the formula (VI) will be described in detail below.

In formula (VI), R ₁ and R ₂ each independently represents a carbon atom or a nitrogen atom. However, R ₁ and R ₂ do not represent a nitrogen atom at the same time.
In formula (VI), Q ₁ and Q ₂ each independently represent a divalent linking group that is linked to R ₁ or R ₂ to form a 5-membered or 6-membered heterocyclic ring. However, the ring Q ₁ is formed with R _1, R _2, and, the ring Q ₂ forms together with R _1, R _2, in each ring, including 1 to 3 nitrogen atoms.

Here, the ring formed by Q ₁ together with R ₁ and R ₂ is a ring formed without Q ₂ . Similarly, the ring Q ₂ forms together with R _1, R ₂ is a ring formed without the Q _1.

In formula (VI), rings which Q ₁ is formed with R _1, R _2, and, where Q ₂ is formed with R _1, R ₂ may have a substituent. Although a substituent is not specifically limited, For example, the following are mentioned.
Halogen atom (fluorine atom, chloro atom, bromine atom or iodine atom), alkyl group (straight chain, branched, cyclic alkyl group including bicycloalkyl group and active methine group), alkenyl group, alkynyl group, aryl group , Heterocyclic group (no matter where it is substituted), acyl group, alkoxycarbonyl group, aryloxycarbonyl group, heterocyclic oxycarbonyl group, carbamoyl group, N-hydroxycarbamoyl group, N-acylcarbamoyl group, N-sulfonylcarbamoyl Group, N-carbamoylcarbamoyl group, thiocarbamoyl group, N-sulfamoylcarbamoyl group, carbazoyl group, carboxy group or a salt thereof, oxalyl group, oxamoyl group, cyano group, carbonimidoyl group, formyl group, hydroxy group, alkoxy Group (ethyleneoxy group young Or an 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, sulfonamido group, ureido group, thioureido group, N-hydroxyureido group, imide group, (alkoxy or aryloxy) carbonylamino group, sulfamoylamino group, semicarbazide group, Thiosemicarbazide group, hydrazino group, ammonio group, oxamoylamino group, N- (alkyl or aryl) sulfonylureido group, N-acylureido group, N-acylsulfamoylamino group, hydroxyamino group, nitro group A heterocyclic group containing a quaternized nitrogen atom (for example, pyridinio group, imidazolio group, quinolinio group, isoquinolinio group), isocyano group, imino group, mercapto group, (alkyl, aryl, or heterocyclic) thio group, (alkyl , Aryl, or heterocyclic) dithio group, (alkyl or aryl) sulfonyl group, (alkyl or aryl) sulfinyl group, sulfo group or a salt thereof, sulfamoyl group, N-acylsulfamoyl group, N-sulfonylsulfamoyl group Or a salt thereof, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, silyl group, alkylidene group, oxo group and the like.
These substituents may be further substituted with the same substituent. If possible, two or more substituents may be bonded to form a ring.

Here, the active methine group means a methine group substituted with two electron-withdrawing groups, and the electron-withdrawing group here means an acyl group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl group. An alkylsulfonyl group, an arylsulfonyl group, a sulfamoyl group, a trifluoromethyl group, a cyano group, a nitro group, and a carbonimidoyl group. Here, the two electron withdrawing groups may be bonded to each other to form a cyclic structure.
Moreover, the said salt means the salt formed with organic cations, such as cations, such as an alkali metal, an alkaline-earth metal, and a heavy metal, and an ammonium ion and a phosphonium ion.

  Among these, preferred substituents include alkyl groups, amino groups, imide groups, carboxy groups or salts thereof, hydroxy groups, carbamoyl groups, sulfo groups or salts thereof, sulfamoyl groups, and the like.

  In the compound represented by formula (VI), more preferred examples include compounds represented by the following formula (VI-I) or (VI-II).

In formula (VI-I) or (VI-II), R _{3 to} R ₉ each independently represents a hydrogen atom or a substituent.

The substituents in R _{3 to} R ₉ in formula (VI-I) or (VI-II) are the ring formed by Q ₁ together with R ₁ and R ₂ in formula (VI), and Q ₂ in R ₁ and R It is synonymous with the substituent which the ring formed with ₂ may have.
In particular at least one alkyl group of R ₃ to R ₆ in compounds represented by formula (VI-I), an amino group, an imido group, a carboxy group or a salt thereof, a hydroxy group, a carbamoyl group, a sulfo group or a salt thereof The compound which is a substituent represented by a sulfamoyl group is preferable, and it is particularly preferable that at least one of R _{3 to} R ₆ is an amino group, a hydroxy group, or an alkyl group.

  The molecular weight of the compound represented by the formula (VI) is preferably 110 to 600, and more preferably 110 to 400.

  Specific examples of the compound represented by the formula (VI) are shown below, but are not limited thereto.

  Among the above compounds, VI-2, VI-11, VI-14, VI-24, VI-26, VI-32, VI-34, VI-35, VI-37, VI-45 are more preferable, VI-2, VI-11, VI-14, VI-24, and VI-26 are particularly preferred.

  The compound represented by the formula (VI) may be a commercially available product or may be synthesized according to a conventional method. For example, compound VI-2 can be synthesized according to the synthesis method described in Chem. Pharm. Bull., 11, 859 (1963), J. Am. Chem. Soc., 82, 605 (1960), etc. .

  The addition amount of the heterocyclic compound other than the compound represented by the formula (I) is preferably 0.00001 to 1.0 mol, more preferably 0.00005, in 1 L of a polishing liquid used for polishing as a total amount. ˜0.5 mol, more preferably 0.0001 to 0.1 mol.

(Additive)
Moreover, it is preferable to use the following additives for the polishing liquid of the present invention.
ammonia;
Alkylamines such as dimethylamine, trimethylamine, triethylamine, propylenediamine, and amines such as ethylenediaminetetraacetic acid (EDTA), sodium diethyldithiocarbamate and chitosan;
Dithizone, cuproin (2,2′-biquinoline), neocuproin (2,9-dimethyl-1,10-phenanthroline), bathocuproine (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) and cupelazone ( Imines such as biscyclohexanone oxalyl hydrazone);
Benzimidazole-2-thiol, 2- [2- (benzothiazolyl)] thiopropionic acid, 2- [2- (benzothiazolyl)] thiobutyric acid, 2-mercaptobenzothiazole, 1,2,3-triazole, 1,2, 4-triazole, 3-amino-1H-1,2,4-triazole, benzotriazole, 1-hydroxybenzotriazole, 1-dihydroxypropylbenzotriazole, 2,3-dicarboxypropylbenzotriazole, 4-hydroxybenzotriazole, 4-carboxyl-1H-benzotriazole, 4-methoxycarbonyl-1H-benzotriazole, 4-butoxycarbonyl-1H-benzotriazole, 4-octyloxycarbonyl-1H-benzotriazole, 5-hexylbenzotriazol N- (1,2,3-benzotriazolyl-1-methyl) -N- (1,2,4-triazolyl-1-methyl) -2-ethylhexylamine, tolyltriazole, naphthotriazole, bis [( Azoles such as 1-benzotriazolyl) methyl] phosphonic acid;
Mercaptans such as nonyl mercaptan, dodecyl mercaptan, triazine thiol, triazine dithiol, triazine trithiol,
Other examples include tetrazole and quinaldic acid.
Among these, chitosan, ethylenediaminetetraacetic acid, cuperazone, triazinedithiol, benzotriazole, 4-hydroxybenzotriazole, 44-butoxycarbonyl-1H-benzotriazole, tolyltriazole, and naphthotriazole satisfy both high CMP rate and low etching rate. Preferred above.

  The additive amount of these additives is preferably 0.0001 mol to 0.5 mol, more preferably 0.001 mol to 0.2 mol, and more preferably 0.005 mol to 0.2 mol in 1 L of a polishing liquid used for polishing. The amount is particularly preferably 0.1 mol. That is, the addition amount of the additive is preferably 0.0001 mol or more from the viewpoint of suppressing etching, and preferably 0.5 mol or less from the viewpoint of preventing a decrease in CMP rate.

(Surfactant and / or hydrophilic polymer)
The polishing liquid of the present invention preferably contains a surfactant and / or a hydrophilic polymer.
Both the surfactant and the hydrophilic polymer have the action of reducing the contact angle of the surface to be polished and the action of promoting uniform polishing. As the surfactant and / or hydrophilic polymer to be used, those selected from the following group are suitable.
Examples of the anionic surfactant include carboxylate, sulfonate, sulfate ester salt and phosphate ester salt. Examples of the carboxylate salt include soap, N-acyl amino acid salt, polyoxyethylene or polyoxypropylene alkyl ether carboxyl. Acid salt, acylated peptide; as sulfonate, alkyl sulfonate, alkyl benzene and alkyl naphthalene sulfonate, naphthalene sulfonate, sulfosuccinate, α-olefin sulfonate, N-acyl sulfonate; sulfate ester Salts include sulfated oil, alkyl sulfates, alkyl ether sulfates, polyoxyethylene or polyoxypropylene alkyl allyl ether sulfates, alkyl amide sulfates; phosphate ester salts such as alkyl phosphates, polyoxyethylene or polyoxypropyls. Can pyrene alkyl allyl ether phosphates.

As cationic surfactant, aliphatic amine salt, aliphatic quaternary ammonium salt, benzalkonium chloride salt, benzethonium chloride, pyridinium salt, imidazolinium salt; carboxybetaine type, aminocarboxylate as amphoteric surfactant And imidazolinium betaine, lecithin, and alkylamine oxide.
Nonionic surfactants include ether type, ether ester type, ester type and nitrogen-containing type. Ether type includes polyoxyethylene alkyl and alkylphenyl ether, alkylallyl formaldehyde condensed polyoxyethylene ether, polyoxyethylene poly Examples include oxypropylene block polymer, polyoxyethylene polyoxypropylene alkyl ether, ether ester type, glycerin ester polyoxyethylene ether, sorbitan ester polyoxyethylene ether, sorbitol ester polyoxyethylene ether, ester type, Polyethylene glycol fatty acid ester, glycerin ester, polyglycerin ester, sorbitan ester, propylene glycol ester , Sucrose esters, nitrogen-containing type, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkyl amide, and the like.
Moreover, a fluorine-type surfactant etc. are mentioned.

  Furthermore, other surfactants, hydrophilic compounds, hydrophilic polymers and the like include esters such as glycerin ester, sorbitan ester, methoxyacetic acid, ethoxyacetic acid, 3-ethoxypropionic acid and alanine ethyl ester; 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 Ete , Polypropylene glycol alkenyl ethers, alkyl polypropylene glycols, alkyl polypropylene glycol alkyl ethers, alkyl polypropylene glycol alkenyl ethers, alkenyl polypropylene glycols, alkenyl polypropylene glycol alkyl ethers and alkenyl polypropylene glycol alkenyl ethers; alginic acid, pectinic acid, carboxymethylcellulose, curd Polysaccharides such as orchid and pullulan; amino acid salts such as glycine ammonium salt and glycine sodium salt; polyaspartic acid, polyglutamic acid, polylysine, polymalic acid,

  Polymethacrylic acid, poly (ammonium methacrylate), poly (methacrylic acid sodium salt), polyamic acid, polymaleic acid, polyitaconic acid, polyfumaric acid, poly (p-styrenecarboxylic acid), polyacrylic acid, polyacrylamide, aminopolyacrylamide, polyacrylic Ammonium acid salt, polyacrylic acid sodium salt, polyamic acid, polyamic acid ammonium salt, polyamic acid sodium salt and polyglyoxylic acid and other salts thereof; vinyl polymers such as polyvinyl alcohol, polyvinylpyrrolidone and polyacrolein; methyl Tauric acid ammonium salt, methyl tauric acid sodium salt, methyl sodium sulfate salt, ethylammonium sulfate salt, butylammonium sulfate salt, vinylsulfonic acid sodium salt, 1- Rylsulfonic acid sodium salt, 2-allylsulfonic acid sodium salt, methoxymethylsulfonic acid sodium salt, ethoxymethylsulfonic acid ammonium salt, 3-ethoxypropylsulfonic acid sodium salt, methoxymethylsulfonic acid sodium salt, ethoxymethylsulfonic acid ammonium salt, Examples include sulfonic acids such as 3-ethoxypropylsulfonic acid sodium salt and sulfosuccinic acid sodium salt and amides such as propionamide, acrylamide, methylurea, nicotinamide, succinic acid amide, and sulfanilamide.

  However, when the substrate to be applied 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. This is not the case when the substrate is a glass substrate or the like. Among the above exemplary compounds, polyacrylic acid ammonium salt, polyvinyl alcohol, succinic acid amide, polo vinyl pyrrolidone, polyethylene glycol, and polyoxyethylene polyoxypropylene block polymer are more preferable.

The total amount of the surfactant and / or hydrophilic polymer added is preferably 0.001 to 10 g and more preferably 0.01 to 5 g in 1 L of a polishing liquid used for polishing. It is particularly preferably 0.1 to 3 g. That is, the addition amount of the surfactant and / or the hydrophilic polymer is preferably 0.001 g or more for obtaining a sufficient effect, and is preferably 10 g or less from the viewpoint of preventing the CMP rate from being lowered.
Moreover, as a weight average molecular weight of these surfactant and / or hydrophilic polymer, 500-100,000 are preferable, and 2,000-50,000 are especially preferable.

(Alkaline agent and buffer)
The polishing liquid of the present invention can contain an alkali agent for pH adjustment and further a buffering agent from the viewpoint of suppressing pH fluctuations, as necessary.

  Alkaline agents and buffering agents include organic ammonium hydroxides such as ammonium hydroxide and tetramethylammonium hydroxide, nonmetallic alkali agents such as alkanolamines such as diethanolamine, triethanolamine, triisopropanolamine, and the like. Alkali metal hydroxides such as sodium, potassium hydroxide and lithium hydroxide, carbonate, phosphate, borate, tetraborate, hydroxybenzoate, glycyl salt, N, N-dimethylglycine salt, leucine Salt, norleucine salt, guanine salt, 3,4-dihydroxyphenylalanine salt, alanine salt, aminobutyrate, 2-amino-2-methyl-1,3-propanediol salt, valine salt, proline salt, trishydroxyaminomethane salt Lysine salt etc. can be used .

Specific examples of the alkali agent and buffer include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, trisodium phosphate, tripotassium phosphate, diphosphate phosphate. Sodium, dipotassium phosphate, sodium borate, potassium borate, sodium tetraborate (borax), potassium tetraborate, sodium o-hydroxybenzoate (sodium salicylate), potassium o-hydroxybenzoate, 5-sulfo Examples include sodium 2-hydroxybenzoate (sodium 5-sulfosalicylate), potassium 5-sulfo-2-hydroxybenzoate (potassium 5-sulfosalicylate), ammonium hydroxide, and tetramethylammonium hydroxide.
Among them, particularly preferable alkali agents are ammonium hydroxide, potassium hydroxide, lithium hydroxide, and tetramethylammonium hydroxide.

  The addition amount of the alkaline agent and the buffer may be an amount that maintains the pH within a preferable range, and is preferably 0.0001 mol to 1.0 mol in 1 L of the polishing liquid used for polishing. More preferably, it is 0.003 mol to 0.5 mol.

2-8 are preferable, as for pH of the metal polishing liquid of this invention, More preferably, it is pH 3-7, More preferably, it is pH 4-7. Within this range, the metal liquid of the present invention exhibits particularly excellent effects.
In addition, the form which does not contain water may be sufficient as the metal polishing liquid of this invention. In this case, the metal polishing liquid having a pH of 2 to 8 represents one having the above pH when the metal polishing liquid of the present invention is dissolved in water.

  In the present invention, depending on the adsorptivity and reactivity 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 set the amount and pH.

(Abrasive grains)
The polishing liquid of the present invention preferably contains abrasive grains. Examples of preferable abrasive grains include silica (precipitated silica, fumed silica, colloidal silica, synthetic silica), ceria, alumina, titania, zirconia, germania, manganese oxide, silicon carbide, polystyrene, polyacryl, polyterephthalate, and the like. It is done.
The abrasive grains preferably have an average particle size of 5 to 1,000 nm, particularly preferably 10 to 200 nm.

  As the addition amount of the abrasive grains, the abrasive grains are preferably in the range of 0.01 to 20% by weight, and in the range of 0.05 to 5% by weight, based on the total weight of the polishing liquid when used. It is more preferable. In order to obtain a sufficient effect on the polishing rate, 0.01% by weight or more is preferable. Since the polishing rate by CMP is saturated, 20% by weight or less is preferable.

  Further, when abrasive grains are not contained or contained at a concentration of less than 0.01% by weight, the polishing rate and dishing characteristics are improved by preferably setting the pH to 3.5 or more, particularly pH 4.0 or more. I found out. In this case, it is preferable to add the aforementioned hydrophilic polymer such as polyacrylic acid, and the addition amount is generally preferably 0.0001 to 5% by weight, more preferably 0.01 to 0.5% by weight. %.

<Chemical mechanical polishing method>
The chemical mechanical polishing method of the present invention (hereinafter also referred to as “CMP method” or “polishing method”) The metal polishing liquid of the present invention is brought into contact with the surface to be polished, and the surface to be polished and the polishing surface are moved relative to each other. And a step of removing at least part of the metal by polishing the substrate on which the metal wiring is formed (hereinafter also referred to as “polishing step”).
The chemical mechanical polishing method of the present invention uses a polishing liquid for metal of the present invention containing a compound represented by the formula (I) and at least one of other chelating agents, so that a polishing rate in CMP is obtained. Excellent corrosion and in-plane uniformity.

(Wiring metal raw materials)
In the present invention, the object to be polished is, for example, a metal wiring in a semiconductor such as LSI, preferably a wiring made of copper metal and / or a copper alloy, particularly a wiring made of a copper alloy. Furthermore, the copper alloy containing silver is preferable among copper alloys. The silver content contained in the copper alloy is preferably 40% by weight or less, particularly preferably 10% by weight or less, more preferably 1% by weight or less, most preferably in the range of 0.00001 to 0.1% by weight. Exhibits excellent effects. As described above, the metal polishing liquid of the present invention is a polishing liquid that can be suitably used for polishing metal wirings in semiconductors such as LSIs, but is accompanied by acid or abrasive grains accompanying the polishing of the metal wirings. Needless to say, the silicon substrate, silicon oxide, silicon nitride, resin, carbon wiring, noble metal wiring, barrier metal film, insulating film, etc. may be partially polished due to the above effects.

(Wiring thickness)
In the present invention, the semiconductor to be polished is preferably an LSI having a wiring with a half pitch of 0.15 μm or less in a DRAM device system, more preferably 0.10 μm or less. More preferably, it is not more than 08 μm. On the other hand, in the MPU device system, an LSI having a wiring of 0.12 μm or less is preferable, 0.07 μm or less is more preferable, and 0.05 μm or less is further preferable.
The polishing liquid of the present invention exhibits particularly excellent effects on these LSIs.

(Average relative speed)
In the present invention, the average relative motion speed (average relative speed) between the polishing surface of the polishing pad and the surface to be polished is an average value of the relative motion speed in the radial direction of a straight line passing through the center of the surface to be polished.
For example, when both the surface to be polished and the polishing surface are rotating bodies, the distance between the respective rotation centers is set as the center-to-center distance L. The relative motion speed of the surface to be polished on the line connecting the centers is obtained and used as the average relative speed.
FIG. 1 is a plan view of a rotary polishing surface including a polishing surface and a surface to be polished for explaining the average relative speed.
In FIG. 1, the distance between the center B of the surface to be polished and the center O of the surface to be polished is L (m), the radius of the surface to be polished is Rp (m), the radius of the surface to be polished is Rw (m), and the angular velocity of the surface to be polished is Let ωp (rad / s) and the angular velocity of the surface to be polished be ωw (rad / s). The relative motion speeds Va, Vb, and Vc at points A, B, and C when Rp> Rw are expressed by the following equations.
A: Va = (L−Rw) * ωp + Rw * ωw
B: Vb = L * ωp
C: Vc = (L + Rw) * ωp−Rw * ωw
In the above manner, the velocity distribution in the radial direction A-C of the surface to be polished is obtained, and the average value obtained by dividing the sum by the number of measurement points is obtained as the average relative motion velocity.
In the present invention, the average relative speed is preferably 0.5 to 5.0 m / s, more preferably 1.0 to 3.5 m / s, and 1.5 to 3.0 m / s. It is particularly preferred.

(Contact pressure)
In the present invention, a value obtained by dividing the force applied to the contact portion between the polishing surface and the surface to be polished by the contact area is defined as the contact pressure. For example, when the entire surface to be polished having a diameter of φ200 mm is pressed against a polished surface having a diameter of φ600 mm with a force of 400 N, the contact area is (0.1) ² π = 3.14 · 10 ⁻² m ^2. The pressure is 400 / (3.14 · 10 ⁻² ) = 12,732 Pa.
The contact pressure applied to the CMP method of the present invention is preferably 1,000 to 25,000 Pa, more preferably 2,000 to 17,500 Pa, and 3,500 to 14,000 Pa. Is more preferable.

  The apparatus that can use the polishing liquid of the present invention is not particularly limited. For example, Mirra Mesa CMP, Reflexion CMP (manufactured by Applied Materials), FREX200, FREX300 (manufactured by Ebara Corporation), NPS3301, NPS2301 (Nikon), A-FP-310A, A-FP-210A (Tokyo Seimitsu Co., Ltd.), 2300TERES (Lamb Research), Momentum (SpeedFam-IPEC) can be cited as preferred examples. .

(Polishing conditions, etc.)
The CMP method of the present invention will be further described.
In the polishing step of the present invention, it is preferable to continuously supply a metal polishing liquid to the polishing pad with a pump or the like during polishing. Although there is no restriction | limiting in this supply amount, it is preferable that the surface of a polishing pad is always covered with polishing liquid. After the polishing, the semiconductor substrate is preferably washed in running water and then dried after removing water droplets adhering to the semiconductor substrate using a spin dryer or the like.
In the polishing method of the present invention, the aqueous solution to be diluted is the same as the aqueous solution described below.
Aqueous solution is water containing at least one of metal oxidizer, metal oxide solubilizer, protective film forming agent, and surfactant in advance, and the components contained in the aqueous solution and the components of the metal polishing liquid to be diluted The total component is made to be a component for polishing using a metal polishing liquid. When diluted with an aqueous solution and used, components that are difficult to dissolve can be blended in the form of an aqueous solution, and the metal polishing liquid can be further concentrated.

  As a method for diluting a concentrated metal polishing liquid by adding water or an aqueous solution, for example, a pipe for supplying a concentrated metal polishing liquid and a pipe for supplying water or an aqueous solution are joined together and mixed. There is a method of supplying the diluted metal polishing liquid to the polishing pad. Mixing is, for example, a method in which liquids collide with each other through a narrow passage under pressure, a method in which a filling such as a glass tube is filled in a pipe, a flow of liquid is repeatedly separated and merged, and in a pipe A commonly used method such as a method of providing blades rotating with power can be employed.

  The supply rate of the metal polishing liquid is preferably 10 to 1,000 ml / min, and more preferably 50 to 500 ml / min.

  In addition, as a method of diluting by adding water or an aqueous solution to the concentrated metal polishing liquid, for example, a pipe for supplying the metal polishing liquid and a pipe for supplying water or an aqueous solution are provided independently, respectively. A method in which a fixed amount of liquid is supplied to the polishing pad and mixed by relative movement between the polishing pad and the surface to be polished can be used. As another method of diluting the concentrated metal polishing liquid, a predetermined amount of the concentrated metal polishing liquid and water or an aqueous solution are mixed in one container, and then the mixed metal is mixed in the polishing pad. There is a method of supplying a polishing liquid.

According to another polishing method of the present invention, the components to be contained in the metal polishing liquid are divided into at least two groups of components, and when they are used, water or an aqueous solution is added to dilute the components on the polishing platen. This is a method in which polishing is performed by supplying a polishing pad, bringing it into contact with the surface to be polished, and moving the surface to be polished and the polishing pad relatively. For example, a metal oxidizing agent is one component (A), an acid, an additive, a surfactant, and water are one component (B), and when they are used, the component (A ) And component (B) are diluted and used.
In addition, the additive component having low solubility is divided into two components (A) and (B), and the oxidizing agent, additive and surfactant are one component (A), and the acid, additive and surfactant are used. And water is used as one component (B), and when they are used, water or an aqueous solution is added to dilute the component (A) and the component (B). In this example, three pipes for supplying the component (A), the component (B), and water or an aqueous solution are required, and dilution mixing is combined into one pipe that supplies the three pipes to the polishing pad. Then, a method of mixing in the pipe, or a method of connecting two pipes and then connecting another pipe is used.

  For example, it is a method in which a constituent component containing an additive that is difficult to dissolve is mixed with another constituent component, a mixing path is lengthened to ensure a dissolution time, and then a pipe of water or an aqueous solution is further combined. As another mixing method, for example, as described above, three pipes are directly guided to the polishing pad and mixed by relative movement of the polishing pad and the surface to be polished, and three components are mixed in one container. And a method for supplying a diluted metal polishing liquid to the polishing pad. In the above polishing method, one component containing a metal oxidant is made 40 ° C. or lower, the other components are heated in the range of room temperature to 100 ° C., and one component and another component or water Or when adding and diluting aqueous solution, it can also be made 40 degrees C or less after mixing. Since the solubility increases when the temperature is high, this is a preferable method for increasing the solubility of the raw material having low solubility in the metal polishing slurry.

  Since the raw material in which other components not containing a metal oxidant are heated and dissolved in the range of room temperature to 100 ° C. is precipitated in the solution when the temperature decreases, when using the component whose temperature has decreased, It is necessary to dissolve the preliminarily heated precipitate. For this, a means for feeding a component liquid that has been heated and dissolved, and a means for stirring a liquid containing a precipitate, feeding the liquid, and heating and dissolving the pipe can be employed. If the temperature of one component containing a metal oxidant is increased to 40 ° C. or higher, the metal oxidant may be decomposed. Therefore, the heated component and the heated component When it is mixed with one component containing a metal oxidant for cooling, the temperature is made 40 ° C. or lower.

  In the present invention, the component of the metal polishing liquid may be divided into two or more parts and supplied to the polishing surface. In this case, it is preferable to divide and supply the component containing an oxide and the component containing an acid. Alternatively, the metal polishing liquid may be a concentrated liquid, and the diluted water may be separately supplied to the polishing surface.

(Barrier metal)
In the present invention, when a wiring made of copper metal and / or a copper alloy is used, it is preferable to provide a barrier layer for preventing copper diffusion between the wiring and the interlayer insulating film. The barrier layer is preferably a metal material having a low electrical resistance, more preferably TiN, TiW, Ta, TaN, W, WN, and particularly preferably Ta, TaN.
As the interlayer insulating film, a thin film of an insulating material having a low dielectric constant is preferable, and a preferable insulating material is a material having a relative dielectric constant of 3.0 or less, more preferably a material having a dielectric constant of 2.8 or less. . Specific examples of preferable low dielectric constant materials include BlackDiamond (Applied Materials), FLARE (Honeywell Electronic Materials), SILK (Dow Chemical), CORAL (Novellus System), LKD (JSR) And HSG (manufactured by Hitachi Chemical Co., Ltd.).

(pad)
The polishing pad used in the present invention 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.
Further, it may contain abrasive grains (for example, ceria, silica, alumina, resin, etc.) used for polishing. In addition, the hardness may be either soft or hard, and either 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. In addition, the surface contacting the polishing surface may be subjected to processing such as lattice grooves / holes / concentric grooves / helical grooves.

(Wafer)
The wafer subjected to CMP using the metal polishing liquid of the present invention preferably has a diameter of 200 mm or more, particularly preferably 300 mm or more. The effect of the present invention is remarkably exhibited when the thickness is 300 mm or more.

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

<Examples 1-16 and Comparative Examples 1-4>
The polishing liquid shown below was prepared, and the polishing test was conducted and evaluated.

(Preparation of polishing liquid)
Compound (type and amount used are listed in Table 3 below)
Chelating agent (type and amount used are listed in Table 3 below)
31% hydrogen peroxide solution 3ml
Colloidal silica (average particle size 30 nm) 40 g / L
The above components were added to pure water so that the total amount of polishing liquid was 1,000 mL. The polishing liquid was adjusted to pH 7.0 using aqueous ammonia and sulfuric acid.

(Polishing test)
Substrate: silicon substrate on which a copper film having a thickness of 1 μm is formed Polishing pad: IC1400 K / XY Groove (manufactured by Nitta Haas)
Polishing machine: FREX (manufactured by Ebara Corporation)
Holding pressure: 70 g / cm ²
Polishing liquid supply rate: 200 ml / min
Wafer diameter: 300mm
Polishing pad / wafer rotation speed: 100/95 rpm

(Evaluation methods)
[1] Corrosion: The polished wiring part (line 100 μm, space 100 μm) was observed with a microscope to evaluate the presence of corrosion (pitting corrosion) on the wiring.
○: Not visually observed.
Δ: Slightly observed.
X: Observed on the entire outer periphery.
[2] In-plane uniformity: The polishing rate was determined by converting the film thickness of the metal film before and after CMP from the electrical resistance value at 49 locations on the wafer surface, and evaluated by the following formula.
In-plane uniformity (%) = [(maximum polishing rate−minimum polishing rate) / (average polishing rate) × 2] × 100
Table 3 shows the corrosion, in-plane uniformity, and average polishing rate obtained by performing CMP using the various polishing liquids.

(Examples 17 and 18, Comparative Example 5)
Evaluation was conducted in the same manner as in Example 1 except that the polishing liquid was changed to the following liquid. The evaluation results are shown in Table 4.
(Preparation of polishing liquid)
Compound (type and amount used are listed in Table 4 below)
Chelating agent (type and amount used are listed in Table 4 below)
Colloidal silica (average particle size 30 nm) 70 g / L
The above components were added to pure water so that the total amount of polishing liquid was 1,000 mL. The polishing liquid was adjusted to pH 6.0 with aqueous ammonia and sulfuric acid.

  As shown in Tables 3 and 4, the polishing liquid of the present invention was found to have a significant improvement effect in terms of polishing rate, corrosion, and in-plane uniformity.

It is a top view of the rotary polishing surface containing the grinding | polishing surface and to-be-polished surface for demonstrating an average relative speed.

Claims (6)

At least one compound represented by the following formula (I);
A metal-polishing liquid comprising at least one other chelating agent.

(In formula (I), each Z independently represents an atomic group that forms a 5- or 6-membered ring.) At least one compound represented by the following formula (I);
At least one other chelating agent;
A metal polishing liquid containing an oxidizing agent,
A metal-polishing liquid, characterized in that the concentration of the oxidizing agent is 1% by weight or less.

(In formula (I), each Z independently represents an atomic group that forms a 5- or 6-membered ring.)   The metal polishing slurry according to claim 2, wherein hydrogen peroxide or persulfate is used as the oxidizing agent.   The total addition amount of the compound represented by the formula (I) is 0.0005 to 0.1 in a molar ratio with respect to the total addition amount of the chelating agent. Polishing liquid for metal.   The metal polishing slurry according to any one of claims 1 to 4, wherein the chelating agent is an amino acid or an aminopolycarboxylic acid. The metal polishing liquid according to claim 1 is brought into contact with the surface to be polished, and the surface to be polished and the polishing surface are moved relative to each other to polish the substrate on which the metal wiring is formed. A process for removing at least a part of the chemical mechanical polishing method, comprising:

Images