TW201741432A - Polishing liquid, manufacturing method of polishing liquid, polishing liquid stock solution, and chemical mechanical polishing method - Google Patents

Abstract

The invention provides a polishing solution that can obtain an excellent polishing rate when applied to CMP and is less likely to cause dishing of the surface to be polished, a method for producing a polishing solution, a polishing solution stock solution, and a chemomechanical polishing method. This polishing solution is a polishing solution for chemomechanical polishing that contains colloidal silica, an amino acid, two or more azole compounds, and an oxidizing agent, wherein a reaction layer having a thickness of 1-20 nm and containing copper atoms is formed on a copper substrate when the polishing solution and a copper substrate are brought into contact for 24 hours.

Description

Polishing liquid, method for producing polishing liquid, polishing liquid stock, and chemical mechanical polishing method

The present invention relates to a polishing liquid, a method for producing a polishing liquid, a polishing liquid stock solution, and a chemical mechanical polishing method.

In the manufacture of a semiconductor integrated circuit (LSI), chemical mechanical polishing (CMP) is used for planarization of bare wafers, planarization of interlayer insulating films, formation of metal plugs, and formation of buried wiring. :chemical mechanical polishing method. As a polishing liquid used for CMP, for example, Patent Document 1 discloses "a polishing liquid characterized in that a reaction layer having a thickness of 100 nm or more is formed on a surface to be polished which is in contact with a polishing liquid for 24 hours." [Prior Art Literature] [Patent Literature]

[Patent Document 1]: JP-A-2004-123931

As a result of examining the polishing liquid described in Patent Document 1, the inventors have found that when colloidal cerium oxide is blended, there is a problem in that the surface to be polished of the object to be polished is likely to be dented.

An object of the present invention is to provide a polishing liquid which, when used in CMP, can obtain an excellent polishing rate and is less likely to cause dents on the surface to be polished. Further, another object of the present invention is to provide a method for producing a polishing liquid, a polishing liquid stock solution, and a chemical mechanical polishing method.

As a result of intensive studies to achieve the above-described problems, the present inventors have found that the polishing liquid can solve the above problems, and the present invention has been completed. The polishing liquid contains a predetermined component and can be formed into a predetermined thickness when it comes into contact with a copper substrate. Reaction layer. That is, it is understood that the above problem can be achieved by the following configuration.

[1] A polishing liquid comprising a colloidal ceria, an amino acid, two or more kinds of azole compounds, and an oxidizing agent for polishing a chemical mechanical polishing liquid. When the polishing liquid is brought into contact with a copper substrate for 24 hours, copper is used. A reaction layer containing a copper atom and having a thickness of 1 to 20 nm is formed on the substrate. [2] The polishing liquid according to [1], wherein the content of the oxidizing agent is 0.3 to 2.0% by mass based on the total mass of the polishing liquid. [3] The polishing liquid according to [1] or [2], wherein the two or more azole compounds contain a benzotriazole compound and an azole compound different from the benzotriazole compound. [4] The polishing liquid according to [3], wherein the azole compound different from the benzotriazole compound is at least selected from the group consisting of a 1,2,4-triazole compound, a pyrazole compound, and an imidazole compound. 1 species. [5] The polishing liquid according to any one of [1] to [4], wherein a mass ratio of the content of the azole compound other than the content of the azole compound having the smallest content in the polishing liquid is More than 1.0 and less than 1000. [6] The polishing liquid according to any one of [1] to [5] wherein the pH is 5.0 to 8.0. [7] The polishing liquid according to any one of [1] to [6] wherein the content of the amino acid is 1.0 to 20% by mass based on the total mass of the polishing liquid. [8] The polishing liquid according to any one of [1] to [7] further comprising an organic solvent, wherein the content of the organic solvent is 0.01 to 2.0% by mass based on the total mass of the polishing liquid. [9] The polishing liquid according to any one of [1] to [8] wherein the amino acid is at least one selected from the group consisting of glycine and methylglycine. [10] The polishing liquid according to any one of [1] to [9] which contains two or more kinds of amino acids. [11] The polishing liquid according to any one of [1] to [10] wherein the oxidizing agent is hydrogen peroxide. [12] A method for producing a polishing liquid, comprising the following dilution process: a slurry solution containing colloidal cerium oxide, an amino acid, or two or more azole compounds, mixing an oxidizing agent or an oxidizing agent and water, thereby obtaining [ The polishing liquid according to any one of [1] to [11]. [13] The method for producing a polishing liquid according to [12], wherein the dilution process is such that the oxidizing agent is mixed with the oxidizing agent or the oxidizing agent and the water in such a manner that the content of the oxidizing agent is 0.3 to 2.0% by mass based on the total mass of the polishing liquid. Process. [14] A polishing liquid stock solution comprising a colloidal cerium oxide, an amino acid, and a polishing liquid stock solution of two or more kinds of azole compounds, and further mixed with an oxidizing agent, an oxidizing agent, and water for production as in [1] The polishing liquid according to any one of [11]. [15] A chemical mechanical polishing method comprising the step of: supplying a polishing liquid according to any one of [1] to [11] to a polishing pad attached to a polishing table, and causing the object to be polished The polished surface is brought into contact with the polishing pad, and the object to be polished and the polishing pad are relatively moved to polish the surface to be polished, thereby obtaining the ground object to be polished. [16] The chemical mechanical polishing method according to [15], wherein the object to be polished contains at least one metal layer selected from the group consisting of copper and a copper alloy. [Effect of the invention]

According to the present invention, it is possible to provide a polishing liquid which can obtain an excellent polishing rate when used in CMP and which is less likely to cause depression on the surface to be polished (hereinafter, also referred to as "having the effect of the present invention" .).

Hereinafter, the present invention will be described in detail based on the embodiments. In addition, since the description of the components described below is completed according to the embodiment of the present invention, the present invention is not limited to the embodiments. In the present specification, the numerical range expressed by "to" means a range including the numerical values described before and after "~" as the lower limit and the upper limit.

[Polishing liquid] The polishing liquid according to an embodiment of the present invention contains a colloidal cerium oxide, an amino acid, two or more kinds of azole compounds, and an oxidizing agent for chemical mechanical polishing, and the polishing liquid is brought into contact with the copper substrate. At 24 hours, a reaction layer containing copper atoms having a thickness of 1 to 20 nm was formed on the copper substrate.

One of the characteristics of the polishing liquid is a feature in which a reaction layer containing a copper atom and having a thickness of 1 to 20 nm is formed on a copper substrate by bringing the polishing liquid into contact with the copper substrate for 24 hours. In the present specification, the reaction layer is formed by immersing a copper substrate having a polished surface of 10 mm × 10 mm in 10 mL of a polishing liquid, and contacting the copper substrate with the polishing liquid at 25 ° C for 24 hours to form a copper substrate. The reaction layer on the grinding surface. Further, when the copper substrate is immersed in the polishing liquid, a laminate in which a copper substrate and another substrate (for example, a tantalum substrate) are laminated may be immersed in the polishing liquid.

The thickness of the reaction layer is preferably 1 nm or more and 2 nm or more. Further, the thickness of the reaction layer is preferably 20 nm or less, more preferably 15 nm or less, and still more preferably 10 nm or less. If the thickness of the above reaction layer is less than 1 nm, it is difficult to obtain a sufficient polishing rate. On the other hand, when the thickness of the above reaction layer exceeds 20 nm, a depression is likely to occur on the surface of the polishing surface. The polishing liquid contains colloidal cerium oxide in order to increase the polishing rate. The colloidal ceria is in contact with the reaction layer in CMP and the reaction layer is removed, so that in the case of producing a polishing liquid of a reaction layer exceeding 20 nm under prescribed conditions, the surface to be polished is more than expected to be cut off. It is speculated that a person is created. Further, the above-described mechanism of action is presumed to be a mechanism for explaining the effect of the present invention in a limited manner based on the above speculation.

The above reaction layer contains a copper atom. The reaction layer may further contain an oxygen atom or the like, and a complex containing a component in the polishing liquid on the surface of the reaction layer is preferred. Here, the thickness of the reaction layer means that after the polishing liquid is brought into contact with the copper substrate for 24 hours, the copper after the contact is observed by a method described in the examples using a scanning electron microscope (SEM). The thickness obtained from the cross section of the substrate.

(pH) The pH of the polishing liquid is not particularly limited, but is usually 1.0 to 14.0. Among them, 5.0 to 8.0 is more preferred, and 6.0 to 7.5 is further preferred. When the pH is in the range of 5.0 to 8.0, when the polishing liquid is used in CMP, the generation of dents is further suppressed. Further, when the pH is 5.0 or more, a polishing liquid having more excellent dispersion stability of colloidal cerium oxide can be obtained. The isoelectric point of the zeta potential on the surface of the colloidal cerium oxide is close to pH 4.0. Therefore, by adjusting the pH of the polishing liquid to be within the above range of the above isoelectric point, a polishing liquid having more excellent dispersion stability can be obtained. . On the other hand, when the pH is 8.0 or less, it is easy to adjust the thickness of the reaction layer under a predetermined condition to a desired range.

[Colloidal cerium oxide] The above polishing liquid contains colloidal cerium oxide as an essential constituent element. The colloidal cerium oxide has a function of cutting off the reaction layer formed in the object to be polished. One of the reasons for exerting the effects of the present invention is that the polishing liquid contains colloidal cerium oxide and the thickness of the reaction layer formed under predetermined conditions is 1 to 20 nm.

The average primary particle diameter of the colloidal cerium oxide is not particularly limited, but from the viewpoint of having more excellent dispersion stability of the polishing liquid, it is preferably from 1 to 100 nm. Further, the above average primary particle diameter can be confirmed by a manufacturer's product catalog or the like. For example, PL-1, PL-3, PL-7, and PL-10H (all of which are trade names, manufactured by FUSO CHEMICAL CO., LTD.) can be mentioned as a commercial product of the above-mentioned colloidal cerium oxide.

The content of the colloidal cerium oxide is not particularly limited, and is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and more preferably 0.05% by mass or more, based on the total mass of the polishing liquid. When the content of the colloidal cerium oxide exceeds 0.05% by mass, when the polishing liquid is used in CMP, a more excellent polishing rate can be obtained. The upper limit is preferably 10% by mass or less, more preferably 5% by mass or less, and still more preferably 0.2% by mass or less. When the polishing liquid is used in CMP, it is less than 0.2% by mass from the viewpoint that the dent is less likely to occur. It is especially good. Further, the colloidal cerium oxide may be used singly or in combination of two or more. In the case where two or more kinds of colloidal cerium oxide are used in combination, the total content is preferably in the above range.

[Amino Acid] The above polishing liquid contains an amino acid. The amino acid is a compound different from the oxidizing agent, and has an effect of promoting oxidation of the metal, pH adjustment of the polishing liquid, and acting as a buffer.

The amino acid is not particularly limited, and a known amino acid can be used. Examples of the amino acid include glycine, α-alanine, β-alanine, N-methylglycine, L-2-aminobutyric acid, L-nuronic acid, and L-oxime. Amine acid, L-leucine or its derivative, L-proline, L-ornithine, L-lysine, taurine, L-serine, L-threonine, L- Threonic acid, L-homoserine, L-tyrosine, L-thyroxine, 4-hydroxy-L-proline, L-cysteine, L-methionine, L-ethyl thiamin Acid, L-cysteine or its derivative, L-oxidized cysteine, L-aspartic acid, L-glutamic acid, 4-aminobutyric acid, L-aspartate, L-Valley Amine amide, azase, L-arginine, L-cutosin, L-citrulline, δ-hydroxy-L-lysine, creatine, L-kynurenine, L - histidine or a derivative thereof and L-tryptophan.

Among them, as the amino acid, glycine, α-alanine, β-alanine, L-aspartic acid or N-methylglycine (the viewpoint of the effect that the polishing liquid has more excellent effects of the present invention) Methylglycine is preferred, and glycine and/or methylglycine are more preferred. Further, the amino acid may be used singly or in combination of two or more. In the case where two or more kinds of amino acids are used in combination, the total content is preferably in the above range. Among them, from the viewpoint of obtaining a polishing liquid having an effect more excellent in the present invention, it is preferred that the polishing liquid contains two or more kinds of amino acids. The two or more kinds of amino acids are not particularly limited, and can be used by combining the above amino acids. Among them, from the viewpoint of obtaining a polishing liquid having an effect more excellent in the present invention, glycine and alanine, alanine, N-methylglycine, and glycine are used as two or more kinds of amino acids. A combination of N-methylglycine is preferred.

Since the polishing liquid contains an amino acid having high reactivity with a copper substrate, it is presumed that the reaction layer can be efficiently formed. Therefore, compared with a polishing liquid containing no amino acid (for example, a polishing liquid containing only other organic acids), it is presumed that the polishing liquid system can obtain an excellent polishing rate even if the thickness of the reaction layer is thin.

The content of the amino acid is not particularly limited, and is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and even more preferably 50% by mass or less based on the total mass of the polishing liquid. More preferably, it is more preferably 25% by mass or less, further preferably 20% by mass or less, and particularly preferably 10% by mass or less. When the content of the amino acid is 0.1% by mass or more, when the polishing liquid is used in CMP, a more excellent polishing rate can be obtained. In addition, when the content of the amino acid is 50% by mass or less, when the polishing liquid is used for CMP, it is less likely to cause dents on the surface to be polished. When the content of the amino acid is 1.0 to 20% by mass based on the total mass of the polishing liquid, a polishing liquid having an effect more excellent in the present invention can be obtained. Further, the amino acid may be used singly or in combination of two or more. In the case where two or more kinds of amino acids are used in combination, the total content is preferably in the above range.

[Two or more kinds of azole compounds] The polishing liquid contains two or more kinds of azole compounds. The azole compound has a function of forming a reaction layer on the surface of the metal to be polished. In the present specification, the azole compound refers to a compound containing a five-membered heterocyclic ring containing one or more nitrogen atoms, and preferably one to four as the number of nitrogen atoms. Further, the azole compound may contain an atom other than the nitrogen atom as a hetero atom. Further, the above-mentioned derivative means a compound having a substituent which the above-mentioned five-membered heterocyclic ring may contain.

Examples of the azole compound include a pyrrole skeleton, an imidazole skeleton, a pyrazole skeleton, an isothiazole skeleton, an isoxazole skeleton, a triazole skeleton, a tetrazolium skeleton, an imidazole skeleton, a thiazole skeleton, an oxazole skeleton, and the like. A compound of an oxazole skeleton, a thiadiazole skeleton, an oxadiazole skeleton, and a tetrazolium skeleton. The azole compound may be an azole compound containing a polycyclic structure further containing a condensed ring on the above skeleton. Examples of the azole compound containing the above polycyclic structure include an anthracene skeleton, an anthracene skeleton, a carbazole skeleton, a benzimidazole skeleton, a carbazole skeleton, a benzoxazole skeleton, a benzothiazole skeleton, and a benzothiazide. A compound of a diazole skeleton and a naphthopylimidazole skeleton.

The substituent which may be contained in the azole compound is not particularly limited, and examples thereof include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom or an iodine atom), and an alkyl group (linear, branched or cyclic alkyl group). It may be a polycyclic alkyl group such as a bicycloalkyl group, or may contain an active methine group, an alkenyl group, an alkynyl group, an aryl group, a heterocyclic group (optional substitution position), a mercapto group, an alkoxycarbonyl group, an aryloxycarbonyl group. A heterocyclic carbonyl group or an aminomethyl fluorenyl group (as an amino group having a substituent, for example, an N-hydroxyaminocarbamyl group, an N-methylaminomethyl fluorenyl group, and an N-sulfonium group) Aminomethylmercapto, N-aminocarbamimidylmethyl, thioaminomethylhydrazine and N-amine sulfonylaminomethyl, etc., carbazolyl, carboxyl or a salt thereof, Alkaloid, oxalylhydrazyl, cyano, carbomino, carbenyl, hydroxy, alkoxy (containing an ethyleneoxy group or a group containing an ethyleneoxy group as a repeating unit), aryloxy , heterocyclic oxy, decyloxy, carbonyloxy, aminomethyl methoxy, sulfonyloxy, amine, decylamino, sulfonylamino, ureido, thioureido, N- Ureyl group, quinone imine group, carbonylamino group, amine sulfonamide group, aminoureido group, thioaminoureido group, mercapto group, ammonium group, oxalylamine group, N-(alkyl or aromatic Sulfhydryl ureido group, N-mercaptoureido group, N-decylamine sulfonamide group, hydroxylamine group, nitro group, heterocyclic group containing a quaternary nitrogen atom (for example, pyridinium group, imidazolyl group) , quinolyl and isoquinolyl), isocyano, imido, fluorenyl, (alkyl, aryl or heterocyclyl)thio, (alkyl, aryl or heterocyclyl) disulfide, (alkyl, aryl)sulfonyl, (alkyl or aryl) sulfinyl, sulfo or a salt thereof, aminesulfonyl (as a sulfonyl group having a substituent, for example, N- Amidoxime sulfonyl group and N-sulfonylamine sulfonyl) or a salt thereof, a phosphino group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a formyl group, and the like. Wherein, 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 such as a bicycloalkyl group may be a polycycloalkyl group, and may also contain an active secondary A base, an alkenyl group, an alkynyl group, an aryl group or a heterocyclic group (optional substitution position) is preferred.

Here, the "active methine group" means a methine group substituted with two electron withdrawing groups. "Electron-absorbing group" means, for example, an anthracenyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an aminomethylcarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, an aminesulfonyl group, a trifluoromethyl group, a cyano group, Nitro or carbon quinone imine. Further, the two electron withdrawing groups may be bonded to each other to form a ring structure. Further, "salt" means a cation such as an alkali metal, an alkaline earth metal or a heavy metal; an organic cation such as an ammonium ion or a cesium ion.

Specific examples of the azole compound include 5-methylbenzotriazole, 5-aminobenzotriazole, benzotriazole, 5,6-dimethylbenzotriazole, and 3-amine. Base-1,2,4-triazole, 1,2,4-triazole, 3,5-dimethylpyrazole, pyrazole and imidazole.

The benzotriazole compound (compound containing a benzotriazole skeleton) and a benzotriazole compound are different from the viewpoint of obtaining a polishing liquid having an effect more excellent in the present invention as two or more kinds of azole compounds. The compound (a compound not containing a benzotriazole skeleton) is preferred. The compound containing a benzotriazole skeleton is strongly coordinated with copper oxidized by an oxidizing agent to easily form a reaction layer. On the other hand, even if the azole compound is used, the compound containing no benzotriazole skeleton is easily coordinated to the oxidized copper to form a reaction layer. It is presumed that a polishing liquid containing a benzotriazole compound and a compound different from benzotriazole is used in a reaction layer formed at the time of CMP, containing a layer formed of a benzotriazole compound and being different from benzotriazole A layer formed by the compound. It is presumed that the layer formed of the benzotriazole compound which is strongly coordinated with the oxidized copper is dense and has a function of further suppressing the generation of the depression. On the other hand, since a layer formed of a compound different from the compound of the benzotriazole compound which is weakly coordinated with the oxidized copper is more easily removed, it is presumed that it is easy to obtain a more excellent polishing speed. Therefore, when the polishing liquid containing the above two or more kinds of azole compounds is used for CMP, a more excellent polishing rate can be obtained, and it is less likely to cause dents on the polishing surface.

The compound which does not contain the above-mentioned benzotriazole skeleton is not particularly limited, but is selected from the group consisting of a 1,2,4-triazole compound and a pyrene according to the viewpoint of obtaining a polishing liquid having an effect more excellent in the present invention. At least one of the group of the azole compound and the imidazole compound is preferred.

The content of each of the above two or more kinds of azole compounds is not particularly limited, and from the viewpoint of obtaining a polishing liquid having an effect more excellent in the present invention, it is 0.0001 to 2 mass, respectively, based on the total mass of the polishing liquid. % is more preferably 0.0005 to 2% by mass, more preferably 0.001 to 2% by mass. The content of each of the two or more kinds of the azole compounds in the polishing liquid is greater than 1.0 (hereinafter referred to as the mass ratio of the content of the azole compound other than the azole compound having the smallest content in the polishing liquid. More preferably, it is more than "10".), more preferably more than 10, more preferably more than 150, more preferably 1,000 or less, and still more preferably 500 or less. If it is in the above range, a polishing liquid having an effect more excellent in the present invention can be obtained. Further, the azole compound having the smallest content in the polishing liquid means that the content of the azole compound is the least in two or more kinds of azole compounds, and the azole compound may be equivalent to a plurality of azole compounds. Further, the azole compound may be used in combination of three or more kinds. When three or more kinds of azole compounds are used in combination, the content of each azole compound is preferably within the above range.

[Oxidant] The polishing liquid contains an oxidizing agent. The oxidizing agent has a function of oxidizing a metal to be polished which is present on the surface to be polished of the object to be polished. The oxidizing agent is not particularly limited, and a known oxidizing agent can be used. Examples of the oxidizing agent include hydrogen peroxide, peroxide, nitric acid, nitrate, iodate, periodate, hypochlorite, chlorite, chlorate, perchlorate, and persulfuric acid. Salt, dichromate, permanganate, ozone water, silver (II) salt and iron (III) salt. Among them, hydrogen peroxide is preferred.

The content of the oxidizing agent is not particularly limited, and is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more based on the total mass of the polishing liquid. Preferably, 15% by mass or less is preferable, 9.0% by mass or less is more preferable, 3.0% by mass or less is further more preferable, and 2.0% by mass or less is particularly preferable, and 1.5% by mass or less is most preferable. When the content of the oxidizing agent is 0.1% by mass or more, when the polishing liquid is used in CMP, a more excellent polishing rate can be obtained. When the content of the oxidizing agent is 9.0% by mass or less, when the polishing liquid is used for CMP, it is less likely to cause dents on the surface to be polished. In addition, when the content of the oxidizing agent is 0.3 to 2.0% by mass based on the total mass of the polishing liquid, a polishing liquid having an effect more excellent in the present invention can be obtained. Further, the oxidizing agent may be used alone or in combination of two or more. When two or more types of oxidizing agents are used in combination, the total content is preferably in the above range.

[Optional Component] The polishing liquid may contain a component other than the above as an optional component. Hereinafter, the arbitrary components will be described.

<Abrasive Grains> The above polishing liquid may further contain abrasive grains other than colloidal cerium oxide.

The abrasive grains are not particularly limited, and known abrasive grains other than colloidal cerium oxide can be used. Examples of the abrasive grains include inorganic cerium polishing such as cerium oxide (precipitated cerium oxide or gas phase cerium oxide other than colloidal cerium oxide), alumina, zirconia, cerium oxide, titanium oxide, cerium oxide, and cerium carbide. Granules; organic particles such as polystyrene, polyacrylic acid, and polyvinyl chloride.

<Organic Acid> The above polishing liquid may further contain an organic acid other than the amino acid. The organic acid other than the amino acid is a compound different from the oxidizing agent. As the above organic acid, a water-soluble organic acid is preferred. The organic acid is not particularly limited, and a known organic acid can be used. Examples of the organic acid include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, 2-methylbutyric acid, n-hexanoic acid, 3,3-dimethylbutyric acid, 2-ethylbutyric acid, and 4 -methylvaleric acid, n-heptanoic acid, 2-methylhexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, benzoic acid, glycolic acid, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, pentane Diacid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid, lactic acid, hydroxyethylimine diacetic acid, iminodiacetic acid and ammonium salts thereof and/or Or a salt such as an alkali metal salt.

<Organic solvent> It is preferred that the polishing liquid contains an organic solvent. The organic solvent is not particularly limited, and a known organic solvent can be used. Among them, a water-soluble organic solvent is preferred. Examples of the organic solvent include a ketone solvent, an ether solvent, an alcohol solvent, a glycol solvent, a glycol ether solvent, and a guanamine solvent. More specifically, for example, acetone, methyl ethyl ketone, tetrahydrofuran, dioxane, dimethyl acetamide, N-methylpyrrolidone, dimethyl hydrazine, acetonitrile, methanol, ethanol, 1-propanol, 2 -propanol, 1-butanol, ethylene glycol, propylene glycol, and ethoxyethanol. Among them, methyl ethyl ketone, tetrahydrofuran, dioxane, N-methylpyrrolidone, methanol, ethanol or ethylene glycol are preferable.

The content of the organic solvent is not particularly limited, and is preferably 0.001 to 5.0% by mass, more preferably 0.01 to 2.0% by mass, based on the total mass of the polishing liquid. When the content of the organic solvent is in the range of 0.01 to 2.0% by mass, a polishing liquid having more excellent defect properties can be obtained. In addition, one type of the organic solvent may be used alone or two or more types may be used in combination. When two or more types of organic solvents are used in combination, the total content is preferably in the above range.

<Surfactant and/or Hydrophilic Polymer> The above polishing liquid may contain a surfactant and/or a hydrophilic polymer. The surfactant and the hydrophilic polymer (hereinafter also referred to as "hydrophilic polymer") have an effect of reducing the contact angle of the polishing liquid on the surface to be polished, and the polishing liquid is easily wetted and spread on the surface to be polished. The surfactant is not particularly limited, and a known surfactant selected from the group consisting of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant can be used. The anionic surfactant may, for example, be a sulfonate such as a carboxylate or an alkylbenzenesulfonic acid, a sulfate salt or a phosphate salt. The cationic surfactant may, for example, be an aliphatic amine salt, an aliphatic quaternary ammonium salt, a benzalkonium chloride salt, benzethonium chloride, a pyridinium salt or an imidazolinium salt. The amphoteric surfactant may, for example, be a carboxybetaine, an aminocarboxylate, an imidazolinium betaine, a lecithin or an alkylamine oxide. Examples of the nonionic surfactant include an ether type, an ether ester type, an ester type, a nitrogen-containing type, a glycol type, and a fluorine-based surfactant. Examples of the hydrophilic polymer include polyethanols such as polyethylene glycol, alkyl ethers of polyethanols, polysaccharides such as polyvinyl alcohol A, polyvinylpyrrolidone, and alginic acid, polymethacrylic acid, and polyacrylic acid. A carboxylic acid-containing polymer, a polypropylene decylamine, a polymethacrylamide, a polyethyleneimine, or the like. Specific examples of such a hydrophilic polymer include water-soluble polymers described in paragraphs 004 to 0044 of JP-A-2009-88243 and JP-A-2007-194261.

In the above embodiment, the water-soluble polymer is preferably a water-soluble polymer selected from the group consisting of polyacrylamide, polymethacrylamide, polyethyleneimine, and polyvinylpyrrolidone. As polypropylene decylamine or polymethacrylamide, having a hydroxyalkyl group on a nitrogen atom (for example, N-(2-hydroxyethyl) acrylamide polymer, etc.) or having a substitution comprising a polyalkylene oxide chain The base is preferably a weight average molecular weight of from 2,000 to 50,000. As the polyethyleneimine, a polyalkylene oxide chain is preferred on the nitrogen atom, and a repeating unit represented by the following formula is more preferred.

[Chemical Formula 1]

In the above formula, n represents a number of from 2 to 200 (the average of the mixture in the case of a mixture). Further, it is preferred that the polyethylene glycol has an HLB (Hydrophile-Lipophile Balance) value of 16 to 19.

The content of the surfactant or the hydrophilic polymer is not particularly limited, and is preferably 0.00001 to 2.0% by mass, more preferably 0.0001 to 1.0% by mass, and 0.0001 to 0.5% by mass, based on the total mass of the polishing liquid. More preferably, 0.0001 to 0.1% by mass is particularly preferred. When the content of the surfactant or the hydrophilic polymer is in the range of 0.0001 to 1.0% by mass, a polishing liquid having an effect more excellent in the present invention can be obtained. Further, the surfactant or the hydrophilic polymer may be used alone or in combination of two or more. Further, a surfactant and a hydrophilic polymer may be used in combination. When two or more kinds of surfactants, two or more kinds of hydrophilic polymers, surfactants, and hydrophilic polymers are used in combination, the total content is preferably in the above range.

<pH adjuster and/or pH buffer> The above-mentioned polishing liquid may further contain a pH adjuster and/or a pH buffer in order to set it as a predetermined pH. As the pH adjuster and/or pH buffer, an acid agent and/or an alkali agent can be mentioned. Further, the pH adjuster and the pH buffer are different from the compounds of the above amino acids. The acid agent is not particularly limited, and a mineral acid is preferred. Examples of the inorganic acid include sulfuric acid, nitric acid, boric acid, and phosphoric acid. Among them, nitric acid is more preferable. The alkali agent is not particularly limited, and examples thereof include ammonia; ammonium hydroxide and organic ammonium hydroxide; alkanolamines such as diethanolamine, triethanolamine, and triisopropanolamine; sodium hydroxide, potassium hydroxide, and hydrogen. An alkali metal hydroxide such as lithium oxide; a carbonate such as sodium carbonate; a phosphate such as trisodium phosphate; a borate and a tetraborate; a hydroxybenzoate. The content of the pH adjuster and/or the pH buffer is not particularly limited as long as the pH is maintained in a desired range, and usually 0.0001 to 0.1% by mass based on the total mass of the polishing liquid. good.

<Water> It is preferred that the polishing liquid contains water. The water contained in the polishing liquid is not particularly limited, and ion-exchanged water or pure water can be used. The content of water is not particularly limited, and is usually preferably from 90 to 99% by mass based on the total mass of the polishing liquid.

<Chelating Agent> The polishing liquid may contain a chelating agent (that is, a hard water softening agent) as needed to reduce the adverse effects of the polyvalent metal ions to be mixed. As the chelating agent, for example, a general hard water softening agent which is a suspending agent for calcium and/or magnesium, and the like can be used, and two or more of the above substances can be used in combination as needed. The content of the chelating agent may be a sufficient amount when the metal ions such as the polyvalent metal ions to be mixed are sequestered. For example, it is preferably 0.001 to 2.0% by mass based on the total mass of the polishing liquid.

The polishing liquid can be produced by a known method. For example, it can be manufactured by mixing the above components. The order and/or timing of mixing the above components are not particularly limited, and colloidal cerium oxide may be previously dispersed in water having adjusted pH, and predetermined components may be sequentially mixed. Further, the oxidizing agent may be separately stored until the polishing agent is used, and the mixture may be mixed just before use. Further, the polishing liquid is preferably produced by the following method.

[Method for Producing Polishing Liquid] A method for producing a polishing liquid according to an embodiment of the present invention includes a method for producing a polishing liquid comprising colloidal cerium oxide, which is hereinafter referred to as a "dilution process". The polishing liquid is obtained by mixing an aqueous solution of an amino acid and two or more kinds of azole compounds with an oxidizing agent, an oxidizing agent, and water.

According to the above production method, the polishing liquid is obtained by mixing the oxidizing agent, the oxidizing agent, and the water with the polishing liquid stock solution containing the predetermined component. Therefore, it is easy to control the content of the oxidizing agent with respect to the total mass of the polishing liquid within a desired range. The reason for this is that there is a case where the oxidizing agent is decomposed over time and the content in the polishing liquid changes.

[Dilution Process] The dilution process is a process in which a slurry containing a predetermined component is mixed with an oxidizing agent or an oxidizing agent and water to obtain a polishing liquid. The state as the slurry is as described. Further, the method of mixing the oxidizing agent, the oxidizing agent, and the water is not particularly limited, and a known method can be used.

<Polishing liquid stock solution> The polishing liquid stock solution used in the above-mentioned dilution process is a polishing liquid stock solution containing colloidal cerium oxide, an amino acid, and two or more kinds of azole compounds, and is used by mixing an oxidizing agent, an oxidizing agent, and water. A slurry of a polishing liquid for producing a polishing liquid. The polishing liquid may be obtained by mixing an oxidizing agent, an oxidizing agent, and water, and may further contain an organic solvent, a surfactant, a hydrophilic polymer, a pH adjuster, or the like, in addition to the above components. pH buffer, water and chelating agents. Further, the polishing liquid stock may contain a total amount of water or a part of water in the total amount of water in the total mass of the polishing liquid obtained by the dilution process. The polishing liquid stock solution is easier to manufacture the polishing liquid because it contains components other than the oxidizing agent. Further, by mixing the oxidizing agent at the time of use to produce a polishing liquid, it is easy to control the content of the oxidizing agent in the polishing liquid to a desired range. The method for producing the polishing liquid stock solution is not particularly limited, and can be produced by a known method. For example, it can be manufactured by mixing the above components. The order of mixing the above components is not particularly limited, and the colloidal cerium oxide may be previously dispersed in the pH-adjusted water and/or the organic solvent, and the predetermined components may be sequentially mixed.

In another aspect of the method for producing a polishing liquid, a method of preparing a concentrated liquid containing a polishing liquid having a predetermined component, and adding at least one selected from the group consisting of an oxidizing agent and water, A polishing fluid of the specified characteristics. The concentrate of the polishing liquid is, for example, a component containing a colloidal cerium oxide, an amino acid, two or more kinds of azole compounds, an oxidizing agent, and a water polishing liquid, and a component other than water is mixed in advance. .

[Chemical Mechanical Polishing Method] The chemical mechanical polishing method according to an embodiment of the present invention includes a chemical mechanical polishing method (hereinafter also referred to as "CMP method") of the following process (hereinafter also referred to as "polishing process"). The polishing pad attached to the polishing table is supplied with the polishing liquid, and the surface to be polished of the object to be polished is brought into contact with the polishing pad, and the object to be polished and the polishing pad are relatively moved to polish the surface to be polished. The body to be ground.

[Abras to be polished] The object to be polished which can be used in the CMP method of the above embodiment is not particularly limited, and includes a body to be polished (metal with at least one metal layer selected from the group consisting of copper and copper alloy). A layer substrate) is preferred. The copper alloy is not particularly limited, and a copper alloy containing silver is preferred. In the case where the copper alloy contains silver, the silver content is preferably 10% by mass or less, more preferably 1% by mass or less, even more preferably 0.1% by mass or less, and more preferably 0.00001% by mass or more. Preferably. The shape of the electrode can also be a through electrode.

The object to be polished used in the CMP method of the above embodiment can be produced, for example, by the following method. First, an interlayer insulating film such as hafnium oxide is laminated on the tantalum substrate. Then, a concave portion (substrate exposed portion) having a predetermined pattern is formed on the surface of the interlayer insulating film by a known method such as resist layer formation or etching, and is an interlayer insulating film including a convex portion and a concave portion. On the interlayer insulating film, as a barrier layer covering the interlayer insulating film along the surface, a film is formed by vapor deposition or chemical vapor deposition (CVD) of ruthenium or the like. In addition, a conductive material layer (hereinafter referred to as a metal layer) which coats the barrier layer so as to fill the concave portion is formed by vapor deposition, plating, CVD, or the like on copper and/or a copper alloy, thereby obtaining The object to be polished of the laminated structure. The thickness of the interlayer insulating film, the barrier layer and the metal layer is preferably 0.01 to 2.0 μm, 1 to 100 nm, and 0.01 to 2.5 μm, respectively. The material constituting the barrier layer is not particularly limited, and a known low-resistance metal material can be used. As the low resistance metal material, for example, TiN, TiW, Ta, TaN, W, or WN is preferable, and Ta or TaN is more preferable.

[Polishing Apparatus] The polishing apparatus capable of performing the above CMP method is not particularly limited, and a known chemical mechanical polishing apparatus (hereinafter also referred to as "CMP apparatus") can be used. As the CMP apparatus, for example, a general CMP apparatus including a holder for holding a workpiece to be polished (for example, a semiconductor substrate or the like) and a polishing pad (a motor having a variable rotation speed or the like) can be used. Grinding platform. As a commercial item, Reflexion (made by Applied Materials, Inc.) can be used, for example.

<Grinding Pressure> In the CMP method of the above embodiment, polishing is preferably carried out at a pressure of 3000 to 25000 Pa, which is a pressure generated at a contact surface between the surface to be polished and the polishing pad, and is preferably polished at 6,500 to 14,000 Pa.

<Rotational Speed of Grinding Platform> In the CMP method of the above embodiment, polishing is preferably carried out at a number of revolutions of the polishing table of 50 to 200 rpm (revolution per minute), and it is preferably carried out at 60 to 150 rpm. Further, in order to relatively move the object to be polished and the polishing pad, the holder can be rotated and/or oscillated, or the polishing table can be rotated by the planet, or the strip-shaped polishing pad can be linearly formed in one direction in the long dimension direction. mobile. In addition, the bracket may be in any state of being fixed, rotated or oscillated. These polishing methods can be appropriately selected by the surface to be polished and/or the polishing apparatus as long as the object to be polished and the polishing pad are relatively moved.

<Method of Supplying Polishing Liquid> In the CMP method of the above embodiment, the polishing liquid is continuously supplied to the polishing pad on the polishing table by a pump or the like while polishing the surface to be polished. There is no limitation on the amount of supply, but the surface of the polishing pad is always coated with the polishing liquid preferably. In addition, the aspect of the polishing liquid is as described above.

As the CMP method of the above embodiment, the following process may be included before the above polishing process. The above-mentioned process includes, for example, a process for mixing a polishing liquid solution containing colloidal cerium oxide, an amino acid, and two or more kinds of azole compounds, and mixing an oxidizing agent, an oxidizing agent, and water. Further, as the above-mentioned process, for example, a concentrated liquid of a polishing liquid containing colloidal cerium oxide, an amino acid, and an oxidizing agent of two or more kinds of azole compounds may be mentioned, and at least one selected from the group consisting of an oxidizing agent and water is mixed. The process of the species. According to the CMP method described above, the oxidizing agent or the like is mixed immediately before use to produce a polishing liquid, whereby the content of the oxidizing agent in the polishing liquid can be more easily controlled to a desired range. In addition, the state of the polishing liquid, the polishing liquid stock, and the concentrated liquid has been described. [Examples]

Hereinafter, the present invention will be described in detail based on examples. The materials, the amounts, the ratios, the processing contents, the processing steps, and the like shown in the following examples can be appropriately changed without departing from the gist of the invention. Therefore, the scope of the invention is not to be construed as limited by the embodiments shown below. In addition, unless otherwise indicated, “%” means “% by mass”.

[Example 1] Each component shown below was mixed to prepare a chemical mechanical polishing liquid.・Colloidal cerium oxide (average primary particle size: 35nm, product name "PL3", manufactured by FUSO CHEMICAL CO., LTD.) 0.1% by mass ・Glycine (corresponding to amino acid) 1.5% by mass ・5-A Benzotriazole (corresponding to an azole compound containing a benzotriazole skeleton) 0.001% by mass ・Ethylene glycol (corresponding to an organic solvent, a part of which is used as a solvent for dissolving 5-methylbenzotriazole). 0.05% by mass ・3-Amino-1,2,4-triazole (corresponding to a compound containing no compound of a benzotriazole skeleton and containing a 1,2,4-triazole skeleton) 0.2% by mass ・Hydrogen peroxide (corresponding to oxidant.) 1.0% by mass ・Residue of water (pure water)

Further, the pH of the polishing liquid in Table 1 was adjusted to a predetermined value using sulfuric acid and/or tetramethylammonium hydroxide as needed.

[Examples 2 to 42] Each of the components of Table 1 was mixed in the same manner as in Example 1 to obtain each of the polishing liquids. In addition, each abbreviation symbol in Table 1 represents the following compounds and the like.・PL3 (colloidal cerium oxide, product name "PL3", manufactured by FUSO CHEMICAL CO., LTD., average primary particle size: 35 nm.) ・PL2 (colloidal cerium oxide, product name "PL2", FUSO CHEMICAL CO., Manufactured by LTD., average primary particle size: 25 nm.) ・Gly (glycine, equivalent to amino acid.) ・Ala (alanine, equivalent to amino acid.) ・Asp (aspartic acid, equivalent to amine Base acid.) ・NMG (N-methylglycine, equivalent to amino acid.) ・5-MBTA (5-methylbenzotriazole, equivalent to an azole compound having a benzotriazole skeleton.)・BTA (benzotriazole, equivalent to an azole compound having a benzotriazole skeleton.) ・5,6-DMBTA (5,6-dimethylbenzotriazole, equivalent to a benzotriazole skeleton) Azole compound.) ・5-ABTA (5-aminobenzotriazole, equivalent to an azole compound containing a benzotriazole skeleton.) ・3-AT(3-Amino-1,2,4-three Azole, equivalent to an azole compound containing no benzotriazole skeleton and an azole compound containing a 1,2,4-triazole skeleton.) ・1,2,4-tris(1,2,4-triazole , equivalent to not containing benzotriene An azole compound having a skeleton and an azole compound containing a 1,2,4-triazole skeleton.) ・3,5-DP (3,5-dimethylpyrazole, equivalent to a benzotriazole skeleton) An azole compound and an azole compound (pyrazole compound) containing a pyrazole skeleton.) • Pyraz (pyrazole) corresponds to an azole compound containing no benzotriazole skeleton and an azole compound containing a pyrazole skeleton. Imidaz (imidazole, equivalent to an azole compound that does not contain a benzotriazole skeleton, and an azole compound (imidazole compound) containing an imidazole skeleton.) ・5-ATZ (5-aminotetrazolium, equivalent to no An azole compound containing a benzotriazole skeleton.) ・ETG (ethylene glycol, equivalent to an organic solvent.) ・EtOH (ethanol, equivalent to an organic solvent) ・RE-610 (product name "Rhodafac RE-610", Made by Rhodia Inc., equivalent to a surfactant.) ・MD-20 (product name "Surfynol MD-20", manufactured by Air Products and Chemicals, Inc., equivalent to a surfactant.) ・DBSH (dodecylbenzene) Sulfonic acid, equivalent to a surfactant.) ・PAA (polyacrylic acid, It is a hydrophilic polymer.) ・PHEAA (N-(2-hydroxyethyl) acrylamide polymer, weight average molecular weight 20000, which corresponds to a hydrophilic polymer.) ・PEIEO (haves a formula including the following formula) Repeated unit of ethylene oxide chain polyethyleneimine, HLB value 18)

[Chemical Formula 2]

[Comparative Example 1] Each of the components shown below was mixed to prepare a chemical mechanical polishing liquid.・Colloidal cerium oxide (product name "PL3") 0.1% by mass ・Malic acid (corresponding to organic acids other than amino acids) 1.5% by mass ・5-methylbenzotriazole 0.001% by mass ・Ethylene glycol 0.05 % by mass ・10% by mass of hydrogen peroxide ・1.0% by mass of polyacrylic acid ・Water (pure water) Residual part

[Comparative Examples 2 and 3] Each component described in Table 1 was mixed to prepare a chemical mechanical polishing liquid.

[Comparative Example 4] Each of the components shown below was mixed to prepare a chemical mechanical polishing liquid.・Colloidal cerium oxide (product name "PL3") 0.1% by mass ・ 1.5% by mass of malic acid ・0.001% by mass of 5-methylbenzotriazole ・0.2% by mass of 3-aminotriazole ・1.0% by mass of hydrogen peroxide・Ethylene glycol 0.05% by mass ・Water (pure water) Residual part

[Measurement of Thickness of Reaction Layer] A copper substrate having a thickness of 1500 nm was cut into about 10 mm square, and 10 ml of the above-mentioned polishing liquid was placed in a polyethylene cup of about 100 ml at room temperature. The immersion was carried out by allowing to stand for 24 hours (about 25 ° C). After the immersion, the sample taken out from the polishing liquid was washed with water, and further air-dried using nitrogen gas to obtain a sample in which a reaction layer was formed on the surface of copper. This sample was subjected to cross-sectional forming processing by a focused ion beam processing apparatus (FIB: Focused Ion Beam) and cross-sectional observation by a scanning electron microscope (SEM) under the measurement conditions shown below, and the thickness of the reaction layer was measured. . The results are shown in Table 1. (FIB processing conditions) Device: FB-2000A type accelerating voltage manufactured by Hitachi, Ltd.: 30 kV Pretreatment: platinum sputter coating → carbon evaporation → tungsten plating (SEM measurement conditions) Device: Hitachi, Ltd. manufactured S-900 Accelerated voltage: 3kV pretreatment: platinum sputter coating

[Evaluation of polishing rate and dent] Under the following conditions, the polishing liquid was supplied while being supplied to the polishing pad, and the polishing rate and the dent were evaluated. - Grinding device: Reflexion (manufactured by Applied Materials, Inc.) - Object to be polished (wafer): (1) Calculation of polishing rate; blank wafer with a diameter of 1.5 mm and a Cu film of 300 mm thick on the substrate (2) For evaluation of dents; copper wiring wafer (patterned wafer) having a diameter of 300 mm (mask pattern 754CMP (ATDF)) ・ polishing pad: IC1010 (manufactured by Rodel Inc.) ・grinding conditions; polishing pressure Contact pressure of the abrasive surface to the polishing pad): 1.5 psi (In addition, in this specification, psi means pound-force per square inch; pounds per square inch means 1 psi = 6794.76 Pa.) Serving speed: 200 ml/ Min Grinding platform rotation speed: 110 rpm Grinding head rotation speed: 100 rpm (evaluation method) Calculation of polishing speed: The blank wafer of (1) was polished for 60 seconds, and the resistance value was performed for 49 portions of the wafer surface at equal intervals. The metal film thickness before and after the polishing was determined by conversion, and the average value of the metal film thickness divided by the polishing time was defined as the polishing rate, and the evaluation was performed based on the following criteria. Further, as the polishing rate, C or more is a practical range. A: The polishing rate is 400 nm/min or more. B: The polishing rate is 300 nm/min or more and less than 400 nm/min. C: The polishing rate is 200 nm/min or more and less than 300 nm/min. D: The polishing rate is less than 200 nm/min.

Evaluation of the depression: For the patterned wafer of (2), in addition to the time when the copper of the non-wiring portion was completely polished, 25% of the polishing was performed for the time, using a contact type differential meter Dektak V320Si (Veeco Instruments, Inc. manufactured by measuring the step difference between the line and the space portion (line 10 μm, space 10 μm), and evaluated according to the following criteria. In addition, evaluation of "G" or more is a practical range. A: The depression is 15 nm or less. B: The depression is more than 15 nm and 20 nm or less. C: The depression exceeds 20 nm and 25 nm or less. D: The depression is more than 25 nm and 30 nm or less. E: The depression is more than 30 nm and 35 nm or less. F: The depression exceeds 35 nm and 40 nm or less. G: The depression exceeds 40 nm and 45 nm or less. H: The depression exceeds 45 nm.

[Table 1]

[Table 2]

From the results shown in Table 1, it is understood that the polishing liquids of Examples 1 to 42 can obtain a desired effect, and the polishing liquid contains chemical equipment including colloidal cerium oxide, amino acid, two or more azole compounds, and an oxidizing agent. The polishing liquid for polishing was formed on the copper substrate which was in contact with the polishing liquid for 24 hours to form a reaction layer having a thickness of 1 to 20 nm. On the other hand, the polishing liquids of Comparative Examples 1 to 4 did not achieve the desired effects. Further, it is understood that the polishing liquids of Examples 1, 3, and 4 having an oxidizing agent content of 0.3 to 2.0% by mass based on the total mass of the polishing liquid are more excellent than the polishing liquids of Examples 2 and 5, and are more excellent in the present invention. effect. Further, the polishing liquid of Example 1 containing two or more kinds of azole compounds, a benzotriazole compound, an azole compound different from the benzotriazole compound, and Example 33 containing two or more kinds of benzotriazole compounds Compared with the polishing liquid of 34, the effect of the present invention is more excellent. Further, the polishing liquids of Examples 1, 7 and 8 in which the mass ratio (B)/(A) of the azole compound (A) and the azole compound (B) is more than 1.0 and 1000 or less, and the examples 6 and Compared with the polishing liquid of 9, when it is used for CMP, it is less likely to cause a depression on the surface to be polished. Further, the polishing liquids of Examples 1, 11, and 12 having a pH of the polishing liquid in the range of 5.0 to 8.0 have more excellent effects of the present invention than the polishing liquids of Examples 10 and 13. Further, the polishing liquids of Examples 1 and 15 having a content of the amino acid of 1.0 to 20% by mass based on the total mass of the polishing liquid were not the lowest in the practical range as compared with the polishing liquids of Examples 14 and 16. The evaluation grade (grinding speed "C") has an effect of the present invention which is more excellent. Further, the polishing liquid of Example 1 or Example 19 of the amino acid-based glycine acid or methylglycine was more excellent in the effects of the present invention than the polishing liquids of Examples 17 and 18. Further, the polishing liquid of Example 32 containing two or more kinds of amino acids has an effect more excellent in the present invention than the polishing liquid of Example 1.

[Production of the polishing liquid stock and the production of the polishing liquid through the polishing liquid stock solution] The colloidal cerium oxide, the amino acid, the two or more azole compounds, the organic solvent, and water described in Example 1 of Table 1 are used. The mixture is mixed to produce a mixed liquid (corresponding to a polishing liquid stock solution). In addition, the content of each component in the mixed liquid was the same as that of Example 1 except that the amount of water was 1/10 of the amount of water of Example 1. Then, the mixture was allowed to stand at room temperature for one week, and then an oxidizing agent and water were added to the mixture to dilute it to 10 times, and a polishing liquid having the same composition as that of the polishing liquid described in Example 1 of Table 1 was produced. The same evaluation as in Example 1 was obtained as a result of various evaluations using the obtained polishing liquid. From this result, it was confirmed that the desired effect can be obtained even if the polishing liquid is prepared by temporarily preparing the polishing liquid stock solution and temporarily placing the polishing liquid stock solution.

no

Claims (16)

A polishing liquid containing a colloidal ceria, an amino acid, two or more kinds of azole compounds, and an oxidizing agent for chemical mechanical polishing, and the copper substrate is placed on the copper substrate after the polishing liquid is brought into contact with the copper substrate for 24 hours. A reaction layer containing a copper atom and having a thickness of 1 to 20 nm is formed thereon. The polishing liquid according to claim 1, wherein the content of the oxidizing agent is 0.3 to 2.0% by mass based on the total mass of the polishing liquid. The polishing liquid according to the first or second aspect of the invention, wherein the two or more azole compounds contain a benzotriazole compound and an azole compound different from the benzotriazole compound. The polishing liquid according to claim 3, wherein the azole compound different from the benzotriazole compound is selected from the group consisting of a 1,2,4-triazole compound, a pyrazole compound, and an imidazole compound. At least one. The polishing liquid according to claim 1, wherein the mass ratio of the content of the azole compound other than the content of the azole compound having the least content in the polishing liquid is more than 1.0 and 1,000 or less. The polishing liquid according to claim 1, wherein the pH is 5.0 to 8.0. The polishing liquid according to claim 1, wherein the content of the amino acid is 1.0 to 20% by mass based on the total mass of the polishing liquid. The polishing liquid according to claim 1, further comprising an organic solvent, wherein the content of the organic solvent is 0.01 to 2.0% by mass based on the total mass of the polishing liquid. The polishing liquid according to claim 1, wherein the amino acid is at least one selected from the group consisting of glycine and methylglycine. The polishing liquid according to claim 1, which contains two or more kinds of the aforementioned amino acids. The polishing liquid according to claim 1, wherein the oxidizing agent is hydrogen peroxide. A method for producing a polishing liquid, comprising the following dilution process: mixing a oxidizing agent or an oxidizing agent and water with a polishing liquid solution containing colloidal cerium oxide, an amino acid, and two or more azole compounds, thereby obtaining a patent application scope The polishing liquid according to any one of the items 1 to 11. The method for producing a polishing liquid according to claim 12, wherein the dilution process is such that the oxidizing agent is mixed with the oxidizing agent or the oxidizing agent in an amount of 0.3 to 2.0% by mass based on the total mass of the polishing liquid. Process for oxidizing agents and water. A polishing liquid stock solution containing a colloidal ceria, an amino acid, and a polishing liquid solution of two or more kinds of azole compounds, and further mixed with an oxidizing agent, an oxidizing agent, and water, and used for the production of the first item of the patent application. The slurry according to any one of the items 11. A chemical mechanical polishing method comprising the following steps: supplying a polishing liquid according to any one of the first to eleventh aspects of the patent application to the polishing pad mounted on the polishing table, and allowing the object to be polished The polishing surface is in contact with the polishing pad, and the object to be polished and the polishing pad are relatively moved to polish the surface to be polished, thereby obtaining a polished object to be polished. The chemical mechanical polishing method according to claim 15, wherein the object to be polished contains at least one metal layer selected from the group consisting of copper and a copper alloy.