JP2016069522A - Composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide means which, when a polishing object having a metal wiring layer is polished, enables reduction of a polishing rate to be suppressed even when a periodic acid (salt) and a predetermined compound such as ethylenediamine tetraacetic acid (EDTA) are used jointly.SOLUTION: There is provided a composition in which a second compound having a chemical structure represented by the following chemical formula 3 is contained in a composition containing periodic acid or a salt thereof and a first compound having a chemical structure represented by the following chemical formula 1 or chemical formula 2. In the formulae, R represents a chemical structure containing 4 or more carbon atoms binding closest two hydroxyl groups in the compound.SELECTED DRAWING: None

Description

  The present invention relates to a composition. The composition according to the present invention can be suitably used for polishing applications. The present invention also relates to a polishing method using the above composition and a method for producing a substrate.

  Along with higher integration and higher speed of LSI, new fine processing technology has been developed. Chemical mechanical polishing (hereinafter referred to as “CMP”) is one of them, and planarization of an interlayer insulating film, formation of contact plugs, embedded wiring in an LSI manufacturing process, particularly a multilayer wiring forming process. Has been applied to the formation of.

  In the formation of contact plugs, tungsten is used as a filling material and a material for its interdiffusion barrier. In forming the contact plug, a manufacturing method is used in which an extra portion other than the contact plug is removed by CMP. Also, in the formation of embedded wiring, recently, in order to improve the performance of LSIs, attempts have been made to use copper or copper alloys as metal wiring as a wiring material. Since copper or copper alloy is difficult to be finely processed by the dry etching method frequently used in the formation of conventional aluminum alloy wiring, a thin film of copper or copper alloy is formed on an insulating film in which grooves have been formed in advance. A so-called damascene method is mainly employed in which the thin film other than the groove is deposited and buried, and the buried wiring is formed by removing the thin film by CMP. In the polishing composition for metals used in CMP, it generally contains a polishing accelerator such as an acid and an oxidizing agent, and further contains abrasive grains as necessary.

  Also, a technique using a corrosion inhibitor has been proposed for the purpose of preventing a decrease in circuit reliability due to dishing or erosion in the wiring layer. For example, Patent Document 1 discloses a CMP slurry containing an abrasive, an oxidizing agent, a complexing agent, a corrosion inhibitor, and water, and a pyridine-based compound containing at least two pyridinyl groups is used as the corrosion inhibitor. In this way, dishing and erosion are suppressed. In Patent Document 1, hydrogen peroxide and periodic acid (salt) are exemplified as the oxidizing agent. Examples of complexing agents include amino acid compounds such as alanine and glycine, and carboxylic acid compounds containing at least two carboxyl groups such as ethylenediaminetetraacetic acid (EDTA).

Special table 2010-515257

  As a result of investigation by the present inventor, when a polishing object having a metal wiring layer is polished using a CMP slurry as described in Patent Document 1, the polishing rate may be remarkably lowered with time. Turned out to be. Specifically, polishing is performed by using periodate (salt) as an oxidizing agent contained in the CMP slurry described in Patent Document 1 and a predetermined compound such as ethylenediaminetetraacetic acid (EDTA) as a complexing agent. It has been found that when the composition for use is constituted, the polishing rate at the time of polishing the polishing object having the metal wiring layer is remarkably lowered with time.

  Therefore, the present invention provides a polishing rate even when a periodic object (salt) and a predetermined compound such as ethylenediaminetetraacetic acid (EDTA) are used in combination when polishing a polishing object having a metal wiring layer. It aims at providing the means which can suppress the fall of.

  The present inventor has intensively studied to solve the above problems. As a result, it has been found that the above problem occurs in a composition containing periodic acid or a salt thereof and a first compound having a chemical structure represented by the following chemical formula 1 or the following chemical formula 2. Further, the following chemical formula 3 It was found that the above-mentioned problems can be solved by including in the composition the second compound having the chemical structure represented by the formula, thereby completing the present invention.

In the formula, R represents a chemical structure including a chain containing 4 or more carbon atoms connecting two closest hydroxy groups in the compound.

  That is, according to one embodiment of the present invention, periodic acid or a salt thereof, a first compound having a chemical structure represented by Chemical Formula 1 or Chemical Formula 2, and a chemical structure represented by Chemical Formula 3 are obtained. A composition comprising a second compound having is provided.

  According to the present invention, even when periodic acid (salt) and a predetermined compound such as ethylenediaminetetraacetic acid (EDTA) are used in combination, it is possible to suppress a decrease in the polishing rate.

Embodiments of the present invention will be described below. In addition, this invention is not limited only to the following embodiment. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may be different from the actual ratios. In the present specification, “X to Y” indicating a range means “X or more and Y or less”, and “weight” and “mass”, “wt%”, “mass%”, “part by weight” “Part by mass” is treated as a synonym. Unless otherwise specified, measurement of operation and physical properties is performed under conditions of room temperature (20 to 25 ° C.) / Relative humidity 40 to 50%.

[Composition]
One embodiment of the present invention includes periodic acid or a salt thereof, a first compound having a chemical structure represented by the following chemical formula 1 or the following chemical formula 2, and a second compound having a chemical structure represented by the following chemical formula 3. It is a composition containing a compound.

  Hereinafter, each component contained in the composition according to the present embodiment will be described in detail.

<Periodic acid or its salt>
Periodic acid is a general term for metaperiodic acid (molecular formula: HIO ₄ ) and orthoperiodic acid (molecular formula: H ₅ IO ₆ ), both of which function as an oxidizing agent. Moreover, as a salt of periodic acid, sodium metaperiodate (NaIO ₄ ), sodium triperiodate sodium trihydrogenate (Na ₂ H ₃ IO ₆ ), potassium orthoperiodate trihydrogen potassium salt (K ₂ H ₃ IO ₆ ), ammonium trihydrogen orthoperiodate ((NH ₄ ) ₂ H ₃ IO ₆ ), and the like. These may be used alone or in admixture of two or more.

<Other oxidizing agents>
The composition according to the present embodiment may further contain an oxidizing agent other than periodic acid or a salt thereof. Examples of the oxidizing agent other than periodate or a salt thereof include persulfates such as hydrogen peroxide, peracetic acid, percarbonate, urea peroxide, sodium persulfate, potassium persulfate, and ammonium persulfate. . These other oxidizing agents may be used alone or in combination of two or more.

  Here, when the composition is a liquid composition, the lower limit of the content (concentration) of the oxidizing agent is preferably 0.1 mM or more, more preferably 1 mM or more, and more preferably 5 mM or more. Further preferred. On the other hand, the upper limit is preferably 1000 mM or less, more preferably 100 mM or less, and even more preferably 50 mM or less. If the concentration of the oxidizing agent is at least the lower limit value, there is an advantage that the polishing rate when the composition according to this embodiment is used for polishing is improved. On the other hand, if the concentration of the oxidizing agent is not more than the upper limit, in addition to being able to suppress the material cost of the composition, there is an advantage that the load after the use of the composition, that is, the waste liquid treatment can be reduced. is there. In addition, when used for polishing, there is an advantage that excessive oxidation of the surface of the object to be polished by the oxidizing agent is less likely to occur. From the viewpoint of the problem-solution of the present invention, the mass proportion of periodic acid or a salt thereof in the total mass of the oxidizing agent is preferably 50% by mass or more, more preferably 80% by mass or more, More preferably, it is 90 mass% or more, Most preferably, it is 95 mass% or more, Most preferably, it is 100 mass%.

<First compound>
The first compound is a compound having a chemical structure represented by Chemical Formula 1 or Chemical Formula 2.

  First, examples of the compound having the chemical structure represented by the chemical formula 1 include 1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, 2,3-pentanediol, oxalic acid, Citric acid, tartaric acid, malic acid, α-hydroxybutyric acid and the like can be mentioned. These “compounds having a chemical structure represented by Chemical Formula 1” are intended to function as compounds that form complexes with copper. Examples of the compound having the chemical structure represented by the chemical formula 2 include diethylenetriaminepentaacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, transcyclohexanediaminetetraacetic acid, 1,2-diaminopropanetetraacetic acid, glycol etherdiaminetetraacetic acid. Examples include acetic acid, ethylenediamine orthohydroxyphenylacetic acid, aminocarboxylic acids such as various amino acids, and aminophosphonic acid. These “compounds having a chemical structure represented by Chemical Formula 2” are also intended to function as compounds that form complexes with copper.

  As described above, in the course of study by the present inventor, a composition containing periodic acid or a salt thereof and the first compound having the chemical structure represented by the chemical formula 1 or the chemical formula 2 is used as the metal wiring layer. It has been found that there is a problem that the polishing rate is lowered when the polishing object is used for polishing purposes. As described above, the present inventor presumes the following as a mechanism that causes a problem of a decrease in the polishing rate when a specific oxidizing agent is used together with a specific compound for polishing purposes. That is, a specific carbon-carbon bond (C—C bond in Chemical Formula 1 and Chemical Formula 2) in the first compound is cleaved by “malaprad glycol oxidative cleavage reaction” in the presence of periodic acid (or a salt thereof). As a result, the first compound is decomposed, and periodic acid (or a salt thereof) as an oxidizing agent is consumed, resulting in a decrease in the polishing rate.

  From the above viewpoint, the content (concentration) of the first compound in the composition is preferably as less as it does not consume periodic acid (salt), but the problem with the combined use of the second compound described later-solution In order for this mechanism to be established, a certain amount of the first compound needs to be included in the composition. The first compound described above functions as a complexing agent or the like when the composition is used for polishing. Considering these, the lower limit of the content (concentration) of the first compound when the composition is a liquid composition is preferably 0.1 mM or more, more preferably 0.5 mM or more. Preferably, it is 1 mM or more. On the other hand, the upper limit is preferably 100 mM or less, more preferably 50 mM or less, and further preferably 20 mM or less.

<Second compound>
The second compound is a compound having a chemical structure represented by the above chemical formula 3. In the chemical formula 3, R represents a chemical structure including a chain containing 4 or more carbon atoms connecting two closest hydroxy groups in the compound. That is, the compound having the chemical structure represented by Chemical Formula 3 has at least two hydroxy groups (—OH groups), and the two closest hydroxy groups (the shortest distance among a combination of two arbitrary hydroxy groups). It can be said that it is a compound having a chemical structure in which a combination having the smallest number of linking atoms is connected by a chain containing 4 or more carbon atoms. The number of carbon atoms in the chemical structure R is essential to be 4 or more, but the number of carbon atoms in the chemical structure R is preferably 4 to 16, more preferably 4 to 10. In addition, the compound having the chemical structure represented by Chemical Formula 3 has four or more adjacent two hydroxy groups (a combination of two arbitrary hydroxy groups that minimizes the number of linked atoms in the shortest distance). A compound having a chemical structure linked by a chain of carbon atoms is preferred. Furthermore, it is also preferable that R has a chemical structure consisting only of carbon atoms, hydrogen atoms, and oxygen atoms. In a preferred embodiment, the compound having the chemical structure represented by Chemical Formula 3 is a dicarboxylic acid or tricarboxylic acid having 4 or more carbon atoms other than the carbon atom of the carboxy group, and particularly preferably a carbon atom in the above range. A number of dicarboxylic acids. Examples of the second compound having such a chemical structure include succinic acid, maleic acid, fumaric acid, itaconic acid, adipic acid, mesaconic acid, acetone dicarboxylic acid, glutaconic acid, glutaric acid, methyl succinic acid, 2, 3 -Dimethylsuccinic acid, 1,2,3-propanetricarboxylic acid, etc. are mentioned.

  The present inventor has found that the above-described problem of a decrease in polishing rate caused when a specific oxidizing agent is used in combination with a specific compound for polishing purposes is solved by further using the second compound together. It was. Although the mechanism by which the above problem is solved by the combined use of the second compound is not clear, the content (concentration) of the second compound is 1:20 to the molar ratio based on periodic acid. It is preferably 20: 1, more preferably 1:10 to 10: 1, and further preferably 1: 5 to 5: 1.

<Abrasive grains>
The composition according to this embodiment may further contain abrasive grains.

  The abrasive used may be any of inorganic particles, organic particles, and organic-inorganic composite particles. Specific examples of the inorganic particles include particles made of metal oxides such as silica, alumina, ceria, titania, silicon nitride particles, silicon carbide particles, and boron nitride particles. Specific examples of the organic particles include polymethyl methacrylate (PMMA) particles. These abrasive grains may be used alone or in combination of two or more. The abrasive grains may be commercially available products or synthetic products. Among these abrasive grains, silica is preferable, and colloidal silica is particularly preferable.

(Surface modification)
The abrasive grains may be surface-modified. Since ordinary colloidal silica has a zeta potential value close to zero under acidic conditions, silica particles are not electrically repelled with each other under acidic conditions and are likely to agglomerate. On the other hand, abrasive grains whose surfaces are modified so that the zeta potential has a relatively large negative value even under acidic conditions are strongly repelled from each other and dispersed well even under acidic conditions, resulting in storage of the polishing composition. Stability will be improved. Such surface-modified abrasive grains can be obtained, for example, by mixing a metal such as aluminum, titanium or zirconium or an oxide thereof with the abrasive grains and doping the surface of the abrasive grains.

(Anion sol)
Of these, colloidal silica having an organic acid immobilized thereon is particularly preferable. The organic acid is immobilized on the surface of the colloidal silica contained in the composition, for example, by chemically bonding the functional group of the organic acid to the surface of the colloidal silica. If the colloidal silica and the organic acid are simply allowed to coexist, the organic acid is not fixed to the colloidal silica. If sulfonic acid, which is a kind of organic acid, is immobilized on colloidal silica, for example, a method described in “Sulfonic acid-functionalized silica through quantitative oxidation of thiol groups”, Chem. Commun. 246-247 (2003). It can be carried out. Specifically, a silane coupling agent having a thiol group such as 3-mercaptopropyltrimethoxysilane is coupled to colloidal silica, and then the sulfonic acid is immobilized on the surface by oxidizing the thiol group with hydrogen peroxide. The colloidal silica thus obtained can be obtained. Alternatively, if the carboxylic acid is immobilized on colloidal silica, for example, “Novel Silane Coupling Agents Containing a Photolabile 2-Nitrobenzyl Ester for Introduction of a Carboxy Group on the Surface of Silica Gel”, Chemistry Letters, 3, 228- 229 (2000). Specifically, colloidal silica having a carboxylic acid immobilized on the surface can be obtained by irradiating light after coupling a silane coupling agent containing a photoreactive 2-nitrobenzyl ester to colloidal silica. .

(Cation sol)
In addition, cationic silica produced by adding a basic aluminum salt or a basic zirconium salt as disclosed in JP-A-4-214022 can also be used as abrasive grains.

(aspect ratio)
The upper limit of the aspect ratio of the abrasive is preferably less than 1.2, more preferably 1.15 or less, and even more preferably 1.1 or less. When the aspect ratio of the abrasive grains is within such a range, the surface roughness due to the shape of the abrasive grains can be improved. The aspect ratio is an average of values obtained by dividing the length of the longest side of the smallest rectangle circumscribing the image of the abrasive grains by a scanning electron microscope by the length of the shorter side of the same rectangle, It can be obtained using general image analysis software.

(Primary particle size)
The lower limit of the average primary particle diameter of the abrasive grains is preferably 5 nm or more, more preferably 7 nm or more, and further preferably 10 nm or more. Further, the upper limit of the average primary particle diameter of the abrasive grains is preferably 200 nm or less, more preferably 150 nm or less, and further preferably 100 nm or less. If the average primary particle diameter of the abrasive grains is a value within such a range, the polishing rate of the object to be polished when the composition is used for polishing is improved, and after polishing using the composition It is possible to further suppress the occurrence of dishing on the surface of the object to be polished. In addition, the average primary particle diameter of an abrasive grain is calculated based on the specific surface area of the abrasive grain measured by BET method, for example.

(Secondary particle size)
The lower limit of the average secondary particle diameter of the abrasive grains is preferably 25 nm or more, more preferably 30 nm or more, and further preferably 35 nm or more. Further, the upper limit of the average secondary particle diameter of the abrasive grains is preferably 300 nm or less, more preferably 260 nm or less, and further preferably 220 nm or less. If the average secondary particle diameter of the abrasive grains is within such a range, the polishing rate of the object to be polished when the composition is used for polishing is improved, and after polishing with the composition The occurrence of surface defects on the surface of the polishing object can be further suppressed. The secondary particles referred to here are particles formed by association of abrasive grains in the composition, and the average secondary particle diameter of the secondary particles is measured by, for example, a dynamic light scattering method.

(D90 / D10)
In the particle size distribution obtained by the laser diffraction scattering method in the abrasive grains in the composition, the particle diameter D90 when the cumulative particle weight reaches 90% of the total particle weight from the fine particle side and 10% of the total particle weight of all the particles. The lower limit of the ratio D90 / D10 of the diameter D10 of the particles when reaching is 1.5 or more, preferably 1.8 or more, and more preferably 2.0 or more. Further, in the particle size distribution obtained by the laser diffraction scattering method in the abrasive grains in the composition, the particle diameter D90 when the cumulative particle weight reaches 90% of the total particle weight from the fine particle side and 10 of the total particle weight of all the particles. The upper limit of the ratio D90 / D10 of the diameter D10 of the particles when reaching% is not particularly limited, but is preferably 5.0 or less, and more preferably 3.0 or less. If D90 / D10 is a value within such a range, the polishing rate of the polishing object when the composition is used for polishing is improved, and the polishing object after polishing with the composition is used. The occurrence of surface defects on the surface can be further suppressed.

  The lower limit of the content of abrasive grains in the composition is preferably 0.005% by weight or more, more preferably 0.5% by weight or more, and further preferably 1% by weight or more. Most preferably, it is at least% by weight. Further, the upper limit of the content of the abrasive grains in the composition is preferably 50% by weight or less, more preferably 30% by weight or less, and further preferably 20% by weight or less. If content of an abrasive grain is more than the lower limit mentioned above, the grinding | polishing speed | rate of the grinding | polishing target object at the time of using a composition for grinding | polishing use will improve. On the other hand, if the content of the abrasive is not more than the above-described upper limit, the cost of the composition can be suppressed, and surface defects are more likely to occur on the surface of the object to be polished after the composition is used for polishing. Can be suppressed.

<PH adjuster>
The pH of the composition according to this embodiment can be adjusted by adding an appropriate amount of a pH adjusting agent. The pH adjuster used as necessary to adjust the pH of the composition to a desired value may be either an acid or a base, and may be either an inorganic compound or an organic compound. The first compound, the second compound, and the complexing agent described later (the first compound or the second compound, which also functions as a complexing agent) function as a pH adjuster. In some cases, the corresponding compound may be used as at least a part of the pH adjusting agent.

  Specific examples of the acid include inorganic acids such as sulfuric acid, nitric acid, boric acid, carbonic acid, hypophosphorous acid, phosphorous acid and phosphoric acid; 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, glycol Acids, salicylic acid, glyceric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, tartaric acid, citric acid and lactic acid and other carboxylic acids, and methanesulfonic acid, And organic acids such as organic sulfuric acid such as ethanesulfonic acid and isethionic acid. These acids may be used individually by 1 type, and may be used in combination of 2 or more type.

  Specific examples of bases that can be used as pH adjusters include alkali metal hydroxides or salts thereof, alkaline earth metal hydroxides or salts thereof, quaternary ammonium hydroxide or salts thereof, ammonia, amines, and the like. Can be mentioned. Specific examples of the alkali metal include potassium and sodium. Specific examples of the salt include carbonate, hydrogen carbonate, sulfate, acetate, and the like. Specific examples of the quaternary ammonium include tetramethylammonium, tetraethylammonium, tetrabutylammonium and the like.

  The quaternary ammonium hydroxide compound includes quaternary ammonium hydroxide or a salt thereof, and specific examples thereof include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide and the like.

  Specific examples of amines include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, monoethanolamine, N- (β-aminoethyl) ethanolamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, anhydrous piperazine , Piperazine hexahydrate, 1- (2-aminoethyl) piperazine, N-methylpiperazine, guanidine and the like. These bases may be used individually by 1 type, and may be used in combination of 2 or more type.

  Among these bases, ammonia, ammonium salts, alkali metal hydroxides, alkali metal salts, quaternary ammonium hydroxide compounds, and amines are preferable. More preferably, ammonia, potassium compound, sodium hydroxide, quaternary ammonium hydroxide compound, ammonium hydrogen carbonate, ammonium carbonate, sodium hydrogen carbonate, and sodium carbonate are applied. Moreover, it is more preferable that the polishing composition contains a potassium compound as a base from the viewpoint of preventing metal contamination. Examples of the potassium compound include potassium hydroxide or salt, and specific examples include potassium hydroxide, potassium carbonate, potassium hydrogen carbonate, potassium sulfate, potassium acetate, potassium chloride and the like.

  The pH range of the composition is preferably 1.5 or more, more preferably 2 or more. If pH is 1.5 or more, when it grind | polishes using a composition, melt | dissolution of a grinding | polishing target will progress and there exists an advantage that a grinding | polishing speed improves. On the other hand, the upper limit of the pH is not particularly limited, but is preferably less than 12 in terms of easy handling. In addition, in this specification, "pH" shall mean the value measured using the pH meter of the model number F-72 by Horiba, Ltd. in liquid temperature (25 degreeC).

<Complexing agent>
The composition according to this embodiment may include a complexing agent. A “complexing agent” is a compound having a function of chemically etching the surface of an object to be polished when the composition is used for polishing, and improves the polishing rate of the object to be polished by the polishing composition. be able to.

  Examples of complexing agents that can be used include inorganic acids or salts thereof, organic acids or salts thereof, nitrile compounds, amino acids, and chelating agents. These complexing agents may be used alone or in admixture of two or more. The complexing agent may be a commercially available product or a synthetic product. The first compound or the second compound described above may function as a complexing agent. In such a case, the first compound or the second compound may be used as at least a part of the complexing agent. It may be used as

  Specific examples of the inorganic acid include hydrochloric acid, sulfuric acid, nitric acid, carbonic acid, boric acid, tetrafluoroboric acid, hypophosphorous acid, phosphorous acid, phosphoric acid, pyrophosphoric acid and the like.

  Specific examples of the organic acid include, for example, 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, monovalent carboxylic acids such as n-heptanoic acid, 2-methylhexanoic acid, n-octanoic acid, 2-ethylhexanoic acid, lactic acid, glycolic acid, glyceric acid, benzoic acid, salicylic acid; oxalic acid, malonic acid, succinic acid, Examples thereof include carboxylic acids such as glutaric acid, gluconic acid, adipic acid, pimelic acid, maleic acid, phthalic acid, fumaric acid, malic acid, tartaric acid and citric acid. Also, sulfonic acids such as methanesulfonic acid, ethanesulfonic acid and isethionic acid can be used.

  As a complexing agent, the inorganic acid or the salt of the organic acid may be used. In particular, when a salt of a weak acid and a strong base, a salt of a strong acid and a weak base, or a salt of a weak acid and a weak base is used, a pH buffering action can be expected. Examples of such salts include, for example, potassium chloride, sodium sulfate, potassium nitrate, potassium carbonate, potassium tetrafluoroborate, potassium pyrophosphate, potassium oxalate, trisodium citrate, (+)-potassium tartrate, hexafluoro A potassium phosphate etc. are mentioned.

  Specific examples of the nitrile compound include acetonitrile, aminoacetonitrile, propionitrile, butyronitrile, isobutyronitrile, benzonitrile, glutaronitrile, methoxyacetonitrile, and the like.

  Specific examples of amino acids include glycine, α-alanine, β-alanine, N-methylglycine, N, N-dimethylglycine, 2-aminobutyric acid, norvaline, valine, leucine, norleucine, isoleucine, phenylalanine, proline, sarcosine, Ornithine, lysine, taurine, serine, threonine, homoserine, tyrosine, bicine, tricine, 3,5-diiodo-tyrosine, β- (3,4-dihydroxyphenyl) -alanine, thyroxine, 4-hydroxy-proline, cysteine, methionine , Ethionine, lanthionine, cystathionine, cystine, cysteic acid, aspartic acid, glutamic acid, S- (carboxymethyl) -cysteine, 4-aminobutyric acid, asparagine, glutamine, azaserine, arginine, canavanine, cytosine Phosphorus, .delta.-hydroxy - lysine, creatine, histidine, 1-methyl - histidine, 3-methyl - include histidine and tryptophan.

  Specific examples of chelating agents include nitrilotriacetic acid, diethylenetriaminepentaacetic acid, ethylenediaminetetraacetic acid, N, N, N-trimethylenephosphonic acid, ethylenediamine-N, N, N ′, N′-tetramethylenesulfonic acid, transcyclohexane Diamine tetraacetic acid, 1,2-diaminopropanetetraacetic acid, glycol ether diamine tetraacetic acid, ethylenediamine orthohydroxyphenylacetic acid, ethylenediamine disuccinic acid (SS form), N- (2-carboxylateethyl) -L-aspartic acid, β -Alanine diacetate, 2-phosphonobutane-1,2,4-tricarboxylic acid, 1-hydroxyethylidene-1,1-diphosphonic acid, N, N'-bis (2-hydroxybenzyl) ethylenediamine-N, N'-diacetic acid 1,2-dihydroxybenzene-4,6 Such as disulfonic acid and the like.

  Among these, at least one selected from the group consisting of inorganic acids or salts thereof, carboxylic acids or salts thereof, and nitrile compounds is preferable. Moreover, an inorganic acid or its salt is more preferable from the viewpoint of the stability of the complex structure with the metal compound contained in the object to be polished when the composition is used for polishing.

  Here, the lower limit of the content (concentration) of the complexing agent when the composition is a liquid composition is preferably 0.1 mM or more, more preferably 0.5 mM or more, and 1 mM or more. More preferably it is. On the other hand, the upper limit is preferably 100 mM or less, more preferably 50 mM or less, and further preferably 30 mM or less. If the concentration of the complexing agent is not less than the lower limit, there is an advantage that the polishing rate when the composition according to this embodiment is used for polishing is improved. On the other hand, if the concentration of the complexing agent is not more than the upper limit value, there is an advantage that the gelation of the slurry can be prevented.

<Metal anticorrosive (heterocyclic compound, surfactant)>
The composition according to the present embodiment can contain a metal anticorrosive. By adding a metal anticorrosive to the composition, it is possible to suppress deterioration of the surface condition such as surface roughness of the polished surface by preventing dissolution of the metal when the composition is used for polishing.

  The metal anticorrosive that can be used is not particularly limited, but is preferably a heterocyclic compound or a surfactant. The number of heterocyclic rings in the heterocyclic compound is not particularly limited. The heterocyclic compound may be a monocyclic compound or a polycyclic compound having a condensed ring. These metal anticorrosives may be used alone or in combination of two or more. In addition, as the metal anticorrosive, a commercially available product or a synthetic product may be used. Further, when a surfactant is used as the metal anticorrosive agent, there is an advantage that it is possible to improve the cleaning efficiency after polishing by imparting hydrophilicity to the polished surface after polishing, and to prevent the adhesion of dirt.

  Specific examples of heterocyclic compounds that can be used as metal anticorrosives include, for example, pyrrole compounds, pyrazole compounds, imidazole compounds, triazole compounds, tetrazole compounds, pyridine compounds, pyrazine compounds, pyridazine compounds, pyridine compounds, indolizine compounds, Indole compound, isoindole compound, indazole compound, purine compound, quinolidine compound, quinoline compound, isoquinoline compound, naphthyridine compound, phthalazine compound, quinoxaline compound, quinazoline compound, cinnoline compound, buteridine compound, thiazole compound, isothiazole compound, oxazole compound, Examples thereof include nitrogen-containing heterocyclic compounds such as isoxazole compounds and furazane compounds.

  More specific examples include pyrazole compounds such as 1H-pyrazole, 4-nitro-3-pyrazolecarboxylic acid, 3,5-pyrazolecarboxylic acid, 3-amino-5-phenylpyrazole, 5 -Amino-3-phenylpyrazole, 3,4,5-tribromopyrazole, 3-aminopyrazole, 3,5-dimethylpyrazole, 3,5-dimethyl-1-hydroxymethylpyrazole, 3-methylpyrazole, 1-methyl Pyrazole, 3-amino-5-methylpyrazole, 4-amino-pyrazolo [3,4-d] pyrimidine, 4-chloro-1H-pyrazolo [3,4-D] pyrimidine, 3,4-dihydroxy-6-methylpyrazolo (3,4-B) -pyridine, 6-methyl-1H-pyrazolo [3,4-b] pyridin-3-amine, etc. It is.

  Examples of imidazole compounds include imidazole, 1-methylimidazole, 2-methylimidazole, 4-methylimidazole, 2-ethyl-4-methylimidazole, 2-isopropylimidazole, benzimidazole, and 5,6-dimethylbenzimidazole. 2-aminobenzimidazole, 2-chlorobenzimidazole, 2-methylbenzimidazole, 2- (1-hydroxyethyl) benzimidazole, 2-hydroxybenzimidazole, 2-phenylbenzimidazole, 2,5-dimethylbenzimidazole, Examples include 5-methylbenzimidazole and 5-nitrobenzimidazole.

  Examples of the triazole compound include, for example, 1,2,3-triazole (1H-BTA), 1,2,4-triazole, 1-methyl-1,2,4-triazole, methyl-1H-1,2, 4-triazole-3-carboxylate, 1,2,4-triazole-3-carboxylic acid, methyl 1,2,4-triazole-3-carboxylate, 1H-1,2,4-triazole-3-thiol, 3,5-diamino-1H-1,2,4-triazole, 3-amino-1,2,4-triazole-5-thiol, 3-amino-1H-1,2,4-triazole, 3-amino- 5-benzyl-4H-1,2,4-triazole, 3-amino-5-methyl-4H-1,2,4-triazole, 3-nitro-1,2,4-triazole, 3-bromo-5 Nitro , 2,4-triazole, 4- (1,2,4-triazol-1-yl) phenol, 4-amino-1,2,4-triazole, 4-amino-3,5-dipropyl-4H-1, 2,4-triazole, 4-amino-3,5-dimethyl-4H-1,2,4-triazole, 4-amino-3,5-dipeptyl-4H-1,2,4-triazole, 5-methyl- 1,2,4-triazole-3,4-diamine, 1H-benzotriazole, 1-hydroxybenzotriazole, 1-aminobenzotriazole, 1-carboxybenzotriazole, 5-chloro-1H-benzotriazole, 5-nitro- 1H-benzotriazole, 5-carboxy-1H-benzotriazole, 5-methyl-1H-benzotriazole, 5,6-dimethyl-1H Benzotriazole, 1- (1 ′, 2′-dicarboxyethyl) benzotriazole, 1- [N, N-bis (hydroxyethyl) aminomethyl] benzotriazole, 1- [N, N-bis (hydroxyethyl) amino Methyl] -5-methylbenzotriazole, 1- [N, N-bis (hydroxyethyl) aminomethyl] -4-methylbenzotriazole, and the like.

  Examples of the tetrazole compound include 1H-tetrazole, 5-methyltetrazole, 5-aminotetrazole, and 5-phenyltetrazole.

  Examples of indazole compounds include, for example, 1H-indazole, 5-amino-1H-indazole, 5-nitro-1H-indazole, 5-hydroxy-1H-indazole, 6-amino-1H-indazole, 6-nitro-1H -Indazole, 6-hydroxy-1H-indazole, 3-carboxy-5-methyl-1H-indazole and the like.

  Examples of indole compounds include 1H-indole, 1-methyl-1H-indole, 2-methyl-1H-indole, 3-methyl-1H-indole, 4-methyl-1H-indole, 5-methyl-1H- Indole, 6-methyl-1H-indole, 7-methyl-1H-indole, 4-amino-1H-indole, 5-amino-1H-indole, 6-amino-1H-indole, 7-amino-1H-indole, 4-hydroxy-1H-indole, 5-hydroxy-1H-indole, 6-hydroxy-1H-indole, 7-hydroxy-1H-indole, 4-methoxy-1H-indole, 5-methoxy-1H-indole, 6- Methoxy-1H-indole, 7-methoxy-1H-indole, 4-chloro-1H- Ndole, 5-chloro-1H-indole, 6-chloro-1H-indole, 7-chloro-1H-indole, 4-carboxy-1H-indole, 5-carboxy-1H-indole, 6-carboxy-1H-indole, 7-carboxy-1H-indole, 4-nitro-1H-indole, 5-nitro-1H-indole, 6-nitro-1H-indole, 7-nitro-1H-indole, 4-nitrile-1H-indole, 5- Nitrile-1H-indole, 6-nitrile-1H-indole, 7-nitrile-1H-indole, 2,5-dimethyl-1H-indole, 1,2-dimethyl-1H-indole, 1,3-dimethyl-1H- Indole, 2,3-dimethyl-1H-indole, 5-amino-2,3-dimethyl-1H- Ndole, 7-ethyl-1H-indole, 5- (aminomethyl) indole, 2-methyl-5-amino-1H-indole, 3-hydroxymethyl-1H-indole, 6-isopropyl-1H-indole, 5-chloro -2-methyl-1H-indole and the like.

  Among these, preferred heterocyclic compounds are triazole compounds, and in particular, 1H-benzotriazole, 5-methyl-1H-benzotriazole, 5,6-dimethyl-1H-benzotriazole, 1- [N, N-bis ( Hydroxyethyl) aminomethyl] -5-methylbenzotriazole, 1- [N, N-bis (hydroxyethyl) aminomethyl] -4-methylbenzotriazole, 1,2,3-triazole, and 1,2,4- Triazole is preferred. Since these heterocyclic compounds have high chemical or physical adsorptive power to the surface of the object to be polished, a stronger protective film can be formed on the surface of the object to be polished. This is advantageous in improving the flatness of the surface of the object to be polished after polishing using the polishing composition of the present invention.

  In addition, the surfactant may be any of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.

  Specific examples of the anionic surfactant include polyoxyethylene alkyl ether acetic acid, polyoxyethylene alkyl sulfate ester, alkyl sulfate ester, polyoxyethylene alkyl sulfate, alkyl sulfate, alkylbenzene sulfonic acid, alkyl phosphate ester, polyoxyethylene ester Ethylene alkyl phosphate ester, polyoxyethylene sulfosuccinic acid, alkyl sulfosuccinic acid, alkyl naphthalene sulfonic acid, alkyl diphenyl ether disulfonic acid, salts thereof and the like are included.

  Specific examples of the cationic surfactant include alkyltrimethylammonium salt, alkyldimethylammonium salt, alkylbenzyldimethylammonium salt, alkylamine salt and the like.

  Specific examples of amphoteric surfactants include alkyl betaines and alkyl amine oxides. Specific examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, sorbitan fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkylamine, alkyl alkanolamide, and the like. It is. These surfactants may be used individually by 1 type, and may be used in combination of 2 or more type.

<Water-soluble polymer>
The composition according to this embodiment can contain a water-soluble polymer. When the composition contains a water-soluble polymer, there is an advantage that the surface roughness of the polished object after polishing is further reduced when the composition is used for polishing.

  Specific examples of the water-soluble polymer include, for example, polystyrene sulfonate, polyisoprene sulfonate, polyacrylate, polymaleic acid, polyitaconic acid, polyvinyl acetate, polyvinyl alcohol, polyglycerin, polyvinyl pyrrolidone, and isoprene sulfonic acid. And acrylic acid copolymer, polyvinylpyrrolidone polyacrylic acid copolymer, polyvinylpyrrolidone vinyl acetate copolymer, salt of naphthalenesulfonic acid formalin condensate, diallylamine hydrochloride sulfur dioxide copolymer, carboxymethylcellulose, carboxymethylcellulose salt , Hydroxyethyl cellulose, hydroxypropyl cellulose, pullulan, chitosan, and chitosan salts. These water-soluble polymers may be used alone or in combination of two or more.

<Preservatives and fungicides>
The composition according to this embodiment may contain a preservative and / or a fungicide.

  Examples of antiseptics and fungicides that can be used in the composition according to this embodiment include 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one. Examples include isothiazoline preservatives, paraoxybenzoates, and phenoxyethanol. These antiseptics and fungicides may be used alone or in combination of two or more.

<Dispersion medium or solvent>
In the composition according to this embodiment, a dispersion medium or solvent for dispersing or dissolving each component is usually used. As the dispersion medium or solvent, an organic solvent and water are conceivable, and among them, water is preferably included. From the viewpoint of inhibiting the action of other components, water containing as little impurities as possible is preferable. Specifically, pure water, ultrapure water, or distilled water from which foreign ions are removed through a filter after removing impurity ions with an ion exchange resin is preferable.

[Method for producing composition]
According to another aspect of the present invention, a method for producing the composition is also provided. The manufacturing method in particular of a composition is not restrict | limited, For example, it can obtain by stirring and mixing each component which comprises the composition which concerns on the 1st form mentioned above in water. That is, the method for producing the composition provided by the present invention is represented by periodic acid or a salt thereof, the first compound having the chemical structure represented by Chemical Formula 1 or Chemical Formula 2, and the Chemical Formula 3. A method for producing a composition comprising a step of mixing a second compound having a chemical structure. Here, the temperature at which each component is mixed is not particularly limited, but is preferably 10 to 40 ° C., and may be heated to increase the dissolution rate. Further, the mixing time is not particularly limited.

[Polishing method and substrate manufacturing method]
The use of the composition according to the first aspect of the present invention and the composition produced by the production method according to the second aspect of the present invention is not particularly limited. However, as a preferred application, these compositions are suitably used for polishing applications. Especially, it uses suitably for grinding | polishing of the grinding | polishing target object which has a metal wiring layer. In addition, it does not restrict | limit especially as a metal which comprises a metal wiring layer, For example, tungsten, copper, aluminum, hafnium, cobalt, nickel, titanium, tantalum, titanium, cobalt, gold, silver, platinum, palladium, rhodium, ruthenium , Iridium, osmium and the like, preferably copper. These metals may be contained in the form of an alloy or a metal compound. In addition, the object to be polished may include a film other than metal, and examples of the constituent material of the film other than metal include silicon and silicon-containing materials. The composition of the present invention can be suitably used for polishing a through silicon via (TSV) wafer as a polishing object having a film composed of silicon or a silicon-containing material.

  Therefore, according to the further another form of this invention, the grinding | polishing method which grind | polishes a grinding | polishing target object using the composition concerning this invention is provided. Moreover, according to the further another form of this invention, the manufacturing method of the board | substrate including the process of grind | polishing a grinding | polishing target object with the said grinding | polishing method is also provided. Here, as described above, a preferable polishing target is a polishing target having a metal wiring layer, and an example thereof is a through silicon via (TSV) wafer.

  As a polishing apparatus, a general holder having a polishing surface plate on which a holder for holding a substrate having a polishing object and a motor capable of changing the number of rotations are attached and a polishing pad (polishing cloth) can be attached. A polishing apparatus can be used. As the polishing pad, a general nonwoven fabric, polyurethane, porous fluororesin, or the like can be used without particular limitation. It is preferable that the polishing pad is grooved so that the polishing liquid accumulates.

  The polishing conditions are not particularly limited. For example, the rotation speed of the polishing platen is preferably 10 to 500 rpm, and the pressure (polishing pressure) applied to the substrate having the object to be polished is 0.1 to 10 psi (0.69 to 69 kPa) is preferred. The method of supplying the polishing composition to the polishing pad is not particularly limited, and for example, a method of continuously supplying with a pump or the like is employed. Although the supply amount is not limited, it is preferable that the surface of the polishing pad is always covered with the polishing composition of the present invention.

  After the polishing, the substrate is washed in running water, and water droplets adhering to the substrate are removed by a spin dryer or the like, and dried to obtain a substrate having a metal wiring layer.

  Next, the embodiment will be described more specifically with reference to examples and comparative examples.

[Preparation of polishing composition]
Each component shown in Table 1 below was stirred and mixed in water (mixing temperature: about 25 ° C., mixing time: about 10 minutes) to prepare polishing compositions of Examples 1 to 7 and Comparative Examples 1 to 10. In addition, about pH of polishing composition, it adjusted to the value shown in Table 1 using tetramethylammonium hydroxide (TMAH). “Abrasive grain A” shown in Table 1 is colloidal silica having an average primary particle size: 35 nm and an average secondary particle size: 68 nm.

[Evaluation of Polishing Composition]
About the polishing composition of each Example and each Comparative Example prepared above, the remaining concentration of periodic acid as an oxidizing agent and the Cu polishing rate immediately after preparation and after storage for 1 week are obtained by the following method. The maintenance rate was evaluated.

<Residual concentration of periodic acid>
The periodic acid concentration in the composition was measured by the following procedure, and the residual concentration of periodic acid in the composition after storage for 1 week was calculated. The results are shown in Table 1 below.
(1) Weigh 3 g of sample.
(2) Dilute to 100 mL (standard) with pure water.
(3) Add 1 mL of concentrated sulfuric acid (standard).
(4) Add 1 teaspoon of potassium iodide.
(5) Stir (120 rpm) with an automatic titrator (manufactured by Hiranuma Sangyo Co., Ltd.).
(6) Redox titration is performed with a 0.1 mol / L aqueous sodium thiosulfate solution.
(7) The operations of (1) to (6) were carried out for each of the composition immediately after preparation and the composition stored for one week after preparation, and the ratio of the drop amount (after one week storage / just after preparation x 100 [% ]), The residual concentration of periodic acid in the composition after storage for 1 week is calculated.

<Polishing speed (polishing rate)>
The polishing rate (polishing rate) of Cu was evaluated using the following polishing conditions. The results are shown in Table 1 below.

(Polishing conditions)
Polishing machine: CMP single-side polishing machine (Engis)
Pad: Polyurethane Pad pressure: 4 psi (about 27.6 kPa)
Plate rotation speed: 60rpm
Flow rate of polishing composition: 100 mL / min
Polishing time: 1 minute Polishing object: 30 mm x 30 mm Cu
Polishing under the above polishing conditions was carried out using each of the composition immediately after preparation and the composition stored for 1 week after preparation, and from the ratio of the polishing rate (after storage for 1 week / immediately after preparation x 100 [%]), The maintenance rate of the Cu polishing rate after storage for 1 week was calculated.

  From the results shown in Table 1, the polishing rate was obtained by polishing a polishing object containing Cu using the composition according to the present invention, even when the composition was stored for 1 week and then polished. It can be seen that the (polishing rate) is maintained at a high value. This is because there is a high correlation between the concentration of periodic acid, which is an oxidizing agent, and the Cu polishing rate. Therefore, the consumption of periodic acid due to the presence of the first compound is related to the presence of the second compound. This is considered to be due to being suppressed by the above.

Claims (9)

Periodic acid or its salts,
A first compound having a chemical structure represented by chemical formula 1 or chemical formula 2 below:
A second compound having a chemical structure represented by the following chemical formula 3;
A composition comprising:
In the formula, R represents a chemical structure including a chain containing 4 or more carbon atoms connecting two closest hydroxy groups in the compound.   The first compound is diethylenetriaminepentaacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, transcyclohexanediaminetetraacetic acid, 1,2-diaminopropanetetraacetic acid, glycol etherdiaminetetraacetic acid, ethylenediamine orthohydroxyphenylacetic acid, aminocarboxylic acid and The composition of Claim 1 which is 1 type, or 2 or more types selected from the group which consists of aminophosphonic acid.   Said second compound is succinic acid, maleic acid, fumaric acid, itaconic acid, adipic acid, mesaconic acid, acetone dicarboxylic acid, glutaconic acid, glutaric acid, methyl succinic acid, 2,3-dimethyl succinic acid and 1,2, The composition according to claim 1 or 2, which is one or more selected from the group consisting of 3-propanetricarboxylic acid.   The composition according to any one of claims 1 to 3, which is a polishing composition.   The composition according to claim 4, which is used for polishing a through silicon via (TSV) wafer.   6. A composition according to claim 5, wherein the pH is greater than 7. Periodic acid or its salts,
A first compound having a chemical structure represented by chemical formula 1 or chemical formula 2 below:
A second compound having a chemical structure represented by the following chemical formula 3;
A method for producing a composition comprising the step of:
In the formula, R represents a chemical structure including a chain containing 4 or more carbon atoms connecting two closest hydroxy groups in the compound.   A polishing method comprising a step of polishing an object to be polished using the composition according to claim 4 or the composition produced by the production method according to claim 7.   The manufacturing method of a board | substrate including the process of grind | polishing the said grinding | polishing target object with the grinding | polishing method of Claim 8.