KR20210036804A - Polishing composition and polishing method - Google Patents

Abstract

Provided is a polishing composition suitable for the use of forming a wiring pattern comprising a silicon material and capable of suppressing a significant reduction in polishing rate by polishing a polishing object in which a film including the silicon material with a silicon-silicon bond is formed on a pattern including an insulating film using a CMP method. The polishing composition of the present invention contains: an abrasive grains; a first water-soluble polymer including a high molecular compound containing a lactam ring and having a weight average molecular weight of less than 300,000; a second water-soluble polymer including a high molecular compound containing a lactam ring and having a weight average molecular weight smaller than the first water-soluble polymer; a basic compound; and water.

Description

Polishing composition and polishing method {POLISHING COMPOSITION AND POLISHING METHOD}

The present invention relates to a polishing composition and a polishing method.

In recent years, along with multilayer wiring on the surface of a semiconductor substrate, when manufacturing a device, a so-called chemical mechanical polishing (CMP) technique has been used in which a semiconductor substrate is polished and planarized. CMP is a method of flattening the surface of an object to be polished (object to be polished) such as a semiconductor substrate by using a polishing composition (slurry) containing abrasive grains such as silica, alumina, and ceria, an anticorrosive agent, and a surfactant, etc. The object (object to be polished) is silicon, polysilicon, a silicon oxide film (silicon oxide), a silicon nitride, a wiring made of a metal or the like, a plug, or the like.

Various proposals have been made so far for a polishing composition used when polishing a semiconductor substrate by CMP.

For example, in Patent Document 1, a polishing composition for improving the polishing properties for polysilicon, particularly the step elimination efficiency, is described. The polishing composition contains abrasive grains (colloidal silica) and an oxidizing agent, and has a pH of 6 or more. According to this polishing composition, since the oxidizing agent is chemically polished by imparting a chemical action to the surface of the polysilicon to be polished in a composition having a pH of 6 or higher, the step-resolved property of the object to be polished having a step difference is improved. It is stated that it is possible.

In addition, Patent Document 1 describes a polishing composition containing 500 ppm of polyvinylpyrrolidone having a weight average molecular weight of 40000 as an example of a water-soluble polymer that is an additive to be blended in order to further improve the step resolution efficiency. This polishing composition has a pH of 9 and contains 0.1% by mass of oxygen peroxide.

Patent Document 2 contains an organic compound having an acetylene bond, a water-soluble vinyl polymer, and water, has a pH of 4 to 9, and is an additive for a CMP polishing agent capable of polishing an inorganic insulating film for a semiconductor by combining it with a cerium oxide slurry for a semiconductor. Is described. It is described that by blending this additive, the polishing uniformity of the entire surface of the wafer can be improved, and the planarization characteristics of the entire surface of the wafer can be improved. In addition, polyvinylpyrrolidone is not illustrated as a water-soluble vinyl polymer.

In Patent Document 3, as a polishing composition for coarse polishing of a silicon wafer, nitrogen containing abrasive grains and two types of identical structures having different weight average molecular weights (a first nitrogen-containing water-soluble polymer and a second nitrogen-containing water-soluble polymer) A polishing composition comprising a water-soluble polymer (polyvinylpyrrolidone, content of 0.005% by mass or less), a basic compound, and water is described. In addition, as the blending ratio of the two types of nitrogen-containing water-soluble polymers, the first nitrogen-containing water-soluble polymer (weight average molecular weight is 300,000 or more): the second nitrogen-containing water-soluble polymer (weight average molecular weight is less than 300,000) = 5: 1 to 1 :20 is described.

Japanese Patent Publication No. 2015-86355 Japanese Patent Publication No. 2008-85058 WO2019/116833 pamphlet

In the manufacturing process of a semiconductor device, for example, a polishing object in which a polysilicon film (a film containing a silicon material having a silicon-silicon bond) is formed on a pattern containing a silicon nitride film (insulating film) is polished by a CMP method, Forming a wiring pattern including a polysilicon film is being carried out. Problems occurring during this polishing include dishing in which the top surface of the wiring pattern including the polysilicon film is concave like a dish, the top surface of the silicon nitride film between the wirings is cut, causing erosion, and the need to be cut. The polysilicon film remains and the silicon nitride film between wiring patterns is not exposed.

Although the polishing composition described in Patent Document 1 is intended to suppress dishing, the polishing rate of the polysilicon film is remarkably lowered by containing an oxidizing agent. The CMP abrasive described in Patent Document 2 contains cerium oxide as an abrasive grain. Cerium oxide is generally expensive, and because it is easily settled, storage stability is inferior.

Since the polishing composition described in Patent Document 3 contains a water-soluble polymer having a molecular weight of 300,000 or more, ``a polishing object in which a film containing a silicon material having a silicon-silicon bond is formed on a pattern including an insulating film is polished by the CMP method. Therefore, it is not suitable for the use of forming a wiring pattern containing a silicon material having a silicon-silicon bond.

An object of the present invention is to form a wiring pattern including a silicon material having a silicon-silicon bond by polishing an object to be polished by a CMP method on which a film containing a silicon material having a silicon-silicon bond is formed on a pattern including an insulating film. It is to provide a polishing composition that is suitable for use (the above problems are suppressed) and that a remarkable decrease in the polishing rate can be suppressed.

In order to solve the above problems, the polishing composition of one aspect of the present invention comprises a polymer compound including an abrasive grain and a lactam ring, a first water-soluble polymer having a weight average molecular weight of less than 300,000, and a lactam ring. A polymer compound is included, and a second water-soluble polymer having a weight average molecular weight smaller than that of the first water-soluble polymer, a basic compound, and water are included.

According to the present invention, a polishing object in which a film including a silicon material having a silicon-silicon bond is formed on a pattern including an insulating film is polished by CMP method to form a wiring pattern including a silicon material having a silicon-silicon bond. While being suitable for use, it is possible to provide a polishing composition capable of suppressing a significant decrease in the polishing rate.

1 is a cross-sectional view showing a polishing object subjected to a polishing test in Examples and an ideal polishing state of the polishing object.
Fig. 2 is a plan view showing a state in which a polysilicon film does not remain on an object to be polished after performing a polishing test in Examples (?).
Fig. 3 is a plan view showing a state where there is no problem (○) although some polysilicon film remains on the object to be polished after performing the polishing test in Examples.
Fig. 4 is a plan view showing a state (x) in which there is a problem with many remaining polysilicon films on the object to be polished after performing the polishing test in Examples.

[An aspect of the present invention]

As described above, the polishing composition of one aspect of the present invention comprises a silica abrasive grain and a polymer compound containing a lactam ring, a first water-soluble polymer having a weight average molecular weight of less than 300,000, and a polymer containing a lactam ring A second water-soluble polymer containing a compound and having a weight average molecular weight smaller than that of the first water-soluble polymer, a basic compound, and water.

According to the polishing composition of one aspect of the present invention, by including both of the first water-soluble polymer and the second water-soluble polymer described above, it does not contain both of the above-described first water-soluble polymer and the second water-soluble polymer, or only one of them. Compared with the containing polishing composition, the polishing properties when polishing an object to be polished including a film containing a silicon material having a silicon-silicon bond are improved.

The first water-soluble polymer and the second water-soluble polymer both contain a polymer compound containing a lactam ring, and both have a weight average molecular weight of less than 300,000. The weight average molecular weight of the second water-soluble polymer is smaller than the weight average molecular weight of the first water-soluble polymer. By including both of the first water-soluble polymer and the second water-soluble polymer (the weight average molecular weight is less than 300,000), compared to a polishing composition that does not contain both or contains only one of them, ``including an insulating film When carrying out the polishing method, the polishing object in which a film containing a silicon material having a silicon-silicon bond is formed on the pattern is polished by the CMP method to form a wiring pattern containing a silicon material having a silicon-silicon bond. The dishing of the pattern is suppressed, the erosion of the insulating film is suppressed, and the insulating film between the wiring patterns is suppressed from being exposed.

Even when a polymer compound containing a lactam ring and two water-soluble polymers having different weight average molecular weights are included, if the weight average molecular weight of one water-soluble polymer is 300,000 or more, when performing the polishing method, the wiring pattern It is easy to become in a state where the insulating film of the liver is not exposed.

The polishing composition of one aspect of the present invention obtains the above-described effects and effects by including both the first water-soluble polymer and the second water-soluble polymer described above, and since it is not necessary to contain an oxidizing agent, a patent document containing an oxidizing agent There is no significant reduction in the polishing rate as in the polishing composition of 1.

[Detailed description of one aspect of the present invention]

Hereinafter, an aspect of the present invention will be described in detail.

<Object to be polished>

Examples of the use of the polishing composition of one aspect of the present invention include polishing an object to be polished including a film containing a silicon material having a silicon-silicon bond.

Examples of the silicon material having a silicon-silicon bond include polysilicon (Poly-Si), amorphous silicon, single crystal silicon, n-type doped single crystal silicon, p-type doped single crystal silicon, and Si-based alloys such as SiGe. . In particular, it is suitable for the use of polishing a thing containing a film containing polysilicon.

The object to be polished including a film containing a silicon material having a silicon-silicon bond is a material other than a silicon material having a silicon-silicon bond, and includes, for example, silicon oxide, silicon nitride, silicon carbonitride (SiCN), metal, etc. .

<Grain>

The polishing composition of one aspect of the present invention includes silica abrasive grains (abrasive grains including silica particles). When cerium oxide is used as the abrasive, the residue of cerium oxide tends to remain on the object to be polished after polishing, so it is not preferable to use cerium oxide.

The kind of silica particles is not particularly limited, and fumed silica, colloidal silica, and the like are exemplified, but colloidal silica is preferred. Examples of the method for producing colloidal silica include a sodium silicate method and a sol-gel method, and colloidal silica produced by any of the production methods is suitably used as silica particles constituting the polishing composition of one aspect of the present invention.

However, from the viewpoint of reducing metal impurities, colloidal silica produced by the sol-gel method is preferred. Colloidal silica produced by the sol-gel method is preferable because it contains a small amount of corrosive ions such as metal impurities or chloride ions having a property to diffuse in a semiconductor. The production of colloidal silica by the sol-gel method can be performed using a conventionally known method, and specifically, a hydrolyzable silicon compound (e.g., alkoxysilane or a derivative thereof) is used as a raw material to be hydrolyzed. By performing a condensation reaction, colloidal silica can be obtained.

The silica particles may have a cationic group. That is, the silica particles may be cationic modified silica particles or cationic modified colloidal silica. As colloidal silica (cation-modified colloidal silica) having a cationic group, colloidal silica having an amino group immobilized on the surface thereof is preferably mentioned. As a method for producing colloidal silica having such a cationic group, aminoethyltrimethoxysilane, aminopropyltrimethoxysilane, aminoethyltriethoxysilane as described in Japanese Patent Laid-Open No. 2005-162533 , A method of immobilizing a silane coupling agent having an amino group such as aminopropyltriethoxysilane, aminopropyldimethylethoxysilane, aminopropylmethyldiethoxysilane, and aminobutyltriethoxysilane to the surface of the silica particles. Thereby, colloidal silica (amino group-modified colloidal silica) in which an amino group is immobilized on the surface can be obtained.

Colloidal silica may have an anionic group. That is, the silica particle may be an anion-modified silica particle or an anion-modified colloidal silica. As colloidal silica having an anionic group (anion-modified colloidal silica), colloidal silica in which anionic groups such as a carboxylic acid group, a sulfonic acid group, a phosphonic acid group, and an aluminic acid group are immobilized on the surface can be preferably mentioned. The method for producing colloidal silica having such an anionic group is not particularly limited, and for example, a method of reacting a silane coupling agent having an anionic group at the terminal and colloidal silica can be mentioned.

As a specific example, if a sulfonic acid group is immobilized on colloidal silica, for example, "Sulfonic acid-functionalized silica through of thiol groups", Chem. Commun. This can be done by the method described in 246-247 (2003). Specifically, a silane coupling agent having a thiol group such as 3-mercaptopropyltrimethoxysilane is coupled to colloidal silica, and then the thiol group is oxidized with hydrogen peroxide. Silica) can be obtained.

If the carboxylic acid group 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, by coupling a silane coupling agent containing a photoreactive 2-nitrobenzyl ester to colloidal silica and then irradiating with light, colloidal silica in which a carboxylic acid group is immobilized on the surface (carboxylic acid-modified colloidal silica) Can be obtained.

The shape of the silica particles is not particularly limited, and may be spherical or non-spherical. Specific examples of the acetabular shape include polygonal columns such as a triangular column or a square column, a columnar shape, a kiln shape in which the central portion of the column swells more than the end portion, a donut shape in which the central portion of the disk is penetrated, a plate shape, and a so-called cocoon having a constricted portion in the center portion. Various shapes, such as a mold shape, a so-called associative spherical shape in which a plurality of particles are integrated, a so-called star candy shape having a plurality of projections on the surface, and a rugby ball shape, are mentioned, and are not particularly limited.

The size of the silica particles is not particularly limited. However, the average primary particle diameter of the silica particles is preferably 20 nm or more, more preferably 40 nm or more, still more preferably 50 nm or more, and particularly preferably 60 nm or more. In addition, the average primary particle diameter of the silica particles is preferably 250 nm or less, more preferably 200 nm or less, further preferably 150 nm or less, and particularly preferably 100 nm or less. Within such a range, defects such as scratches can be suppressed on the surface of the object to be polished after polishing using the polishing composition. That is, the average primary particle diameter of the silica particles is preferably 20 nm or more and 250 nm or less, more preferably 40 nm or more and 200 nm or less, still more preferably 50 nm or more and 150 nm or less, and 60 nm or more and 100 nm or less. It is particularly preferred. In addition, the average primary particle diameter of the silica particles is calculated, for example, based on the specific surface area of the silica particles measured by the BET method.

The average secondary particle diameter of the silica particles is preferably 50 nm or more, more preferably 80 nm or more, further preferably 100 nm or more, and particularly preferably 120 nm. In addition, the average secondary particle diameter of the silica particles is preferably 500 nm or less, more preferably 400 nm or less, further preferably 300 nm or less, and particularly preferably 250 nm or less. Within such a range, defects such as scratches can be suppressed on the surface of the object to be polished after polishing using the polishing composition. That is, the average secondary particle diameter of the silica particles is preferably 50 nm or more and 500 nm or less, more preferably 80 nm or more and 400 nm or less, still more preferably 100 nm or more and 300 nm or less, and 120 nm or more and 250 nm or less. It is particularly preferred. In addition, the average secondary particle diameter of the silica particles can be measured by, for example, a dynamic light scattering method typified by a laser diffraction scattering method.

The average degree of association of the silica particles is preferably 5.0 or less, more preferably 3.0 or less, and still more preferably 2.5 or less. As the average degree of association of the silica particles decreases, the occurrence of defects on the surface of the object to be polished can be further reduced. Moreover, it is preferable that it is 1.0 or more, and, as for the average degree of association of silica particles, it is more preferable that it is 1.2 or more. As the average degree of association of the silica particles increases, there is an advantage in that the polishing rate by the polishing composition is improved. In addition, the average degree of association of the silica particles is obtained by dividing the value of the average secondary particle diameter of the silica particles by the value of the average primary particle diameter.

The aspect ratio of the silica particles is not particularly limited, but it is preferably less than 2.0, more preferably 1.8 or less, and even more preferably 1.5 or less. In such a range, defects on the surface of the object to be polished can be further reduced. In addition, the aspect ratio is an average of values obtained by taking the smallest rectangle circumscribed to the image of silica particles by a scanning electron microscope and dividing the length of the long side of the rectangle by the length of the short side of the same rectangle. It can be obtained using software. The aspect ratio of the silica particles is not particularly limited, but is preferably 1.0 or more.

In the particle size distribution determined by the laser diffraction scattering method of silica particles, 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 the total particle Although D90/D10, which is the ratio of the particle diameter (D10) when reached, is not particularly limited, it is preferably 1.1 or more, more preferably 1.2 or more, and still more preferably 1.3 or more. In addition, in the particle size distribution obtained by the laser diffraction scattering method in the silica particles in the polishing composition, the particle diameter (D90) and the total particles when the cumulative particle weight reaches 90% of the total particle weight from the fine particle side. The ratio D90/D10 of the particle diameter (D10) when reaching 10% of the total particle weight of is not particularly limited, but is preferably 2.04 or less. In such a range, defects on the surface of the object to be polished can be further reduced.

The size of the silica particles (average primary particle diameter, average secondary particle diameter, aspect ratio, D90/D10, etc.) can be appropriately controlled by selection of a method for producing silica particles or the like.

The content (concentration) of the silica particles in the polishing composition of one aspect of the present invention is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, still more preferably 0.1% by mass or more, and 0.5% by mass or more. It is particularly preferred. In addition, the content of the silica particles in the polishing composition is preferably 20% by mass or less, more preferably 10% by mass or less, still more preferably 5% by mass or less, and particularly preferably 3% by mass or less. When the content of the silica particles is in such a range, it is possible to further suppress the occurrence of surface defects on the surface of the object to be polished after polishing using the polishing composition. In addition, when the polishing composition contains two or more types of silica particles, the content of the silica particles is intended as the total amount thereof.

The polishing composition of one aspect of the present invention may contain other abrasive grains in addition to the silica particles. Examples of other abrasive grains include metal oxide particles such as alumina particles, zirconia particles, and titania particles.

<First water-soluble polymer, second water-soluble polymer>

The polishing composition of one aspect of the present invention comprises a polymer compound containing a lactam ring, a first water-soluble polymer having a weight average molecular weight of less than 300,000, and a polymer compound containing a lactam ring, and the weight average molecular weight is And a second water-soluble polymer smaller than the first water-soluble polymer.

The weight average molecular weight of the first water-soluble polymer is preferably 25,000 or more and less than 300,000, more preferably 30,000 or more and 200,000 or less, and still more preferably 35,000 or more and 150,000 or less.

The weight average molecular weight of the second water-soluble polymer is preferably 1,000 or more and less than 25,000, more preferably 3,000 or more and 20,000 or less, and still more preferably 5,000 or more and 15,000 or less.

As a combination of the weight average molecular weight of the first water-soluble polymer and the weight average molecular weight of the second water-soluble polymer, the weight average molecular weight of the first water-soluble polymer is 25,000 or more and less than 300,000, and the weight average molecular weight of the second water-soluble polymer is 1,000 or more and less than 25,000. Preferably, the weight average molecular weight of the first water-soluble polymer is 30,000 or more and 200,000 or less, and more preferably the weight average molecular weight of the second water-soluble polymer is 3,000 or more and 20,000 or less, and the weight average molecular weight of the first water-soluble polymer is 35,000 or more and 150,000 or less. 2 The weight average molecular weight of the water-soluble polymer is 5,000 or more and 15,000 or less.

As the first water-soluble polymer and the second water-soluble polymer, a homopolymer composed of a monomer containing a compound containing a lactam ring, or a monomer containing a compound containing a lactam ring and a monomer containing a compound not containing a lactam ring. The composed copolymer is mentioned.

Examples of the monomer containing the compound containing a lactam ring include vinylpyrrolidone, vinyl caprolactam, vinylvalerolactam, vinyllaurolactam, and vinylpiperidone.

As a homopolymer composed of a monomer containing a compound containing a lactam ring, selected from the group consisting of polyvinylpyrrolidone, polyvinyl caprolactam, polyvinylvalerolactam, polyvinyllaurolactam, and polyvinyl piperidone At least one type is mentioned.

It is particularly preferable that the first water-soluble polymer and the second water-soluble polymer are polyvinylpyrrolidone.

In the polishing composition of one aspect of the present invention, the total content of the first water-soluble polymer and the second water-soluble polymer is preferably 0.05% by mass or less. Within such a range, it is advantageous to maintain a high polishing rate of polysilicon.

In the polishing composition of one aspect of the present invention, the ratio (W1/W2) of the content rate (W1) of the first water-soluble polymer and the content rate (W2) of the second water-soluble polymer is preferably 1/15 or more and 15/1 or less. And, it is more preferable that it is 1/10 or more and 10/1 or less, and it is especially preferable that it is 1.

<Basic compound>

The polishing composition of one aspect of the present invention contains a basic compound.

As the basic compound containing the polishing composition of one aspect of the present invention, for example, selected from the group consisting of a hydroxide of an alkali metal, an alkali metal salt of an inorganic acid, an ammonium salt of an inorganic acid, an alkali metal salt of an organic acid, an ammonium salt of an organic acid, and ammonia. At least one alkali compound is mentioned. By using these alkali compounds, not only can the pH be adjusted in the alkaline region where silicon contained in the polishing object is easily dissolved, but the alkali compound is not adsorbed to the abrasive grain surface or the polishing object surface during polishing, and most of the alkali compounds are dissolved in the dispersion medium. Therefore, there is no impediment to the removal of silicon, and efficient polishing can be realized.

Examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, and the like.

Examples of the alkali metal salt of the inorganic acid include alkali metal salts of nitrite such as sodium nitrite and potassium nitrite; Alkali metal salts of nitric acid such as sodium nitrate and potassium nitrate; Alkali metal salts of molybdic acid such as sodium molybdate and potassium molybdate; Alkali metal salts of hypochlorous acid such as sodium hypochlorite and potassium hypochlorite; Alkali metal salts of sulfuric acid such as sodium sulfate and potassium sulfate; Alkali metal salts of carbonic acid such as sodium carbonate and potassium carbonate; Alkali metal salts of hydrochloric acid such as sodium chloride and potassium chloride; Alkali metal salts of phosphoric acid such as sodium phosphate and potassium phosphate; Alkali metal salts of silicic acid such as sodium silicate and potassium silicate; Alkali metal salts of boric acid, such as sodium borate and potassium borate, etc. are mentioned.

Examples of the ammonium salt of inorganic acid include ammonium chloride, ammonium sulfate, ammonium amide sulfate, ammonium nitrate, monoammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium diphosphate, ammonium carbonate, ammonium hydrogen carbonate, ammonium sulfide, ammonium borate And ammonium borofluoride.

Examples of alkali metal salts of organic acids include sodium acetate, potassium acetate, sodium propionate, potassium propionate, sodium glycerate, potassium glycerate, sodium malate, potassium malate, sodium citrate, potassium citrate, sodium lactate, potassium lactate, sodium tartrate, potassium tartrate , Sodium salicylate, potassium salicylate, sodium malonate, potassium malonate, sodium succinate, potassium succinate, sodium maleate, potassium maleate, sodium phthalate, potassium phthalate, sodium oxalate, potassium oxalate, sodium glutarate, potassium glutarate , Sodium abietate, potassium abietate, sodium sorbate, potassium sorbate, 2,4,6-octatriene-1-carboxylate, 2,4,6-octatriene-1-carboxyl Potassium acid, sodium eleostearate, potassium eleostearate, 2,4,6,8-decatetraene-1-carboxylate, 2,4,6,8-decatetraene-1-carboxyl Potassium acid, sodium retinoate, potassium retinoate, potassium iminodiacetate, etc. are mentioned.

Examples of the ammonium salt of an organic acid include ammonium formate, ammonium acetate, diamonium oxalate, ammonium hydrogen oxalate, ammonium benzoate, ammonium citrate, diammonium citrate, triammonium citrate, ammonium lactate, ammonium phthalate, ammonium succinate, ammonium tartrate, 2 tartaric acid Ammonium, ammonium aspartate, etc. are mentioned.

Among these alkali compounds, at least one selected from potassium hydroxide, potassium salts of inorganic acids, ammonium salts of inorganic acids, potassium salts of organic acids, ammonium salts of organic acids, and ammonia is used for the purpose of preventing malfunction of semiconductor devices obtained by polishing. It is desirable to do it.

<water>

The polishing composition of one aspect of the present invention contains water as a dispersion medium.

From the viewpoint of suppressing contamination of the object to be polished or inhibiting the action of other components, as the dispersion medium, it is preferable to contain water containing no impurities as much as possible. As such water, water having a total content of transition metal ions of 100 ppb or less is preferable. Here, the purity of water can be increased by operations such as removal of impurity ions using an ion exchange resin, removal of foreign matters by a filter, and distillation. Specifically, as water, it is preferable to use deionized water (ion-exchanged water), pure water, ultrapure water, distilled water, or the like.

Usually, it is preferable that 90% by volume or more of the dispersion medium contained in the polishing composition is water, more preferably 95% by volume or more of water, more preferably 99% by volume or more of water, and particularly that 100% by volume is water. desirable.

<Erogen inhibitor>

It is preferable that the polishing composition of one aspect of the present invention further contains an erosion inhibitor containing a surfactant or a compound having a guanidino group.

As the erosion inhibitor containing a surfactant, any of anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants may be used, but anionic surfactants are preferably used.

Examples of erosion inhibitors containing anionic surfactants include alkyl sulfuric acid (salt), alkyl phosphoric acid (salt), alkylnaphthalenesulfonic acid (salt), alkylbenzenesulfonic acid (salt), polyoxyalkylene alkylsulfonic acid (salt), and polyoxy. Alkylene styrenated phenyl sulfuric acid (salt), polyoxyalkylene alkylsulfosuccinic acid (salt), polyoxyalkylene allylphenyl ether phosphoric acid (salt), polyoxyalkylene alkyl phosphoric acid (salt), polyoxyalkylene alkylacetic acid ( Salt), polyoxyalkylene alkyl sulfosuccinic acid (salt), alkyl sulfosuccinic acid (salt), alkyl naphthalene sulfonic acid (salt), and alkyldiphenyl ether disulfonic acid (salt). Among them, it is preferable to use a branched sodium alkylbenzenesulfonate (C9-17), sodium dodecylbenzenesulfonate, or a polyoxyethylene (n=45-55) allylphenyl ether phosphate amine salt.

Examples of the erosion inhibitor containing a compound having a guanidino group include creatinine, arginine, and glycocyamine. Among them, it is preferable to use creatinine or arginine.

When the polishing composition of one aspect of the present invention contains an erosion inhibitor containing a surfactant, the content is preferably 0.00001% by mass or more, more preferably 0.00005% by mass or more, and even more preferably 0.0001% by mass or more. Do. In addition, when the polishing composition contains an erosion inhibitor containing a surfactant, the content is preferably 0.01% by mass or less, more preferably 0.005% by mass or less, and still more preferably 0.001% by mass or less. If it is less than 0.00001 mass%, the erosion suppression effect is not substantially obtained, and if it exceeds 0.01 mass%, the polishing rate of the polysilicon film is lowered.

When the polishing composition of one aspect of the present invention contains an erosion inhibitor containing a compound having a guanidino group, the content is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and 0.05% by mass. It is more preferable that it is above. In addition, when the polishing composition contains an erosion inhibitor containing a compound having a guanidino group, the content is preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less. Do. If it is less than 0.001 mass%, the erosion suppression effect is not substantially obtained, and if it exceeds 5 mass%, the polishing rate of the polysilicon film decreases.

<Other additives>

It is preferable that the polishing composition of one aspect of the present invention does not contain an oxidizing agent.

The polishing composition of one aspect of the present invention is a chelating agent, a thickening agent, a dispersing agent, a surface protecting agent, a wetting agent, a surfactant (other than that included as an erosion inhibitor), and dissolving within a range that does not impair the effects of the present invention. You may further contain well-known additives, such as an auxiliary agent. The content of the additive may be appropriately set according to the purpose of the addition.

<Ph of the polishing composition>

It is preferable that the pH of the polishing composition of one aspect of the present invention is 8 or higher. When the pH is 8 or more, the polishing rate is improved compared to the case where the pH is less than 8. It is more preferable that it is 8.5 or more, and as for this pH, it is still more preferable that it is 9.0 or more, and it is especially preferable that it is 9.5 or more. On the other hand, from the viewpoint of safety, the pH of the polishing composition is preferably 13.0 or less, more preferably 12.0 or less, and even more preferably 11.5 or less.

That is, the preferred pH range of the polishing composition of one aspect of the present invention is 8.0 or more and 13.0 or less, more preferably 8.5 or more and 12.0 or less, still more preferably 9.0 or more and 11.5 or less, and particularly preferably 9.5 or more and 11.5 or less. Below. Therefore, it is preferable to adjust the amount of the basic compound to be within the above pH range.

<Method of manufacturing composition for polishing>

The method for preparing the polishing composition of one aspect of the present invention is not particularly limited, and for example, silica particles, a first water-soluble polymer, a second water-soluble polymer, a basic compound, and other additives as necessary are added in water as a dispersion medium. It can be obtained by stirring and mixing. The details of each component are as described above.

The temperature at the time of mixing each component is not particularly limited, but is preferably 10°C or more and 40°C or less, and may be heated to increase the dissolution rate. In addition, the mixing time is not particularly limited as long as it can be uniformly mixed.

<Polishing method>

A polishing method for polishing an object to be polished including a film containing a silicon material having a silicon-silicon bond using the polishing composition of one embodiment of the present invention will be described below.

As the polishing apparatus, a holder for holding a substrate or the like having an object to be polished, a motor capable of changing the number of rotations, and the like are provided, and a general polishing apparatus having a polishing plate capable of attaching a polishing pad (polishing cloth) can be used.

As the polishing pad, a general nonwoven fabric, polyurethane, porous fluororesin, etc. can be used without particular limitation. It is preferable that the polishing pad is subjected to grooving in which the polishing liquid is stored.

Regarding the polishing conditions, for example, the rotational speed of the polishing platen is preferably ^{10 rpm (0.17 s -1} ) or more and 500 rpm (8.3 s ^{-1 ).} The pressure (polishing pressure) applied to the substrate having the object to be polished is preferably 0.5 psi (3.4 kPa) or more and 10 psi (68.9 kPa) or less. The method of supplying the polishing composition to the polishing pad is also not particularly limited, and a method of continuously supplying by a pump or the like is employed. Although there is no limit to this supply amount, it is preferable that the surface of the polishing pad is always covered with the polishing composition of one aspect of the present invention.

After the polishing is completed, the substrate is washed in running water, and the water droplets deposited on the substrate are removed by a spin dryer or the like, and dried, thereby obtaining a substrate having a layer containing a metal.

The polishing composition of one aspect of the present invention may be a one-component type or a multi-component type including a two-component type. Further, the polishing composition of one aspect of the present invention may be prepared by diluting the stock solution of the polishing composition with a diluent such as water, for example, by 10 times or more.

[Example 1]

Hereinafter, examples and comparative examples of the present invention will be described, but the present invention is not limited to the examples shown below. In addition, in the examples shown below, technically preferable limitations are made in order to implement the present invention, but this limitation is not an essential requirement of the present invention. In addition, various changes or improvements may be added to the following embodiments, and forms to which such changes or improvements are added may also be included in the present invention.

<Preparation of composition for polishing>

(Example 1)

Polyvinylpyrrolidone having a weight average molecular weight of 40000 as the first water-soluble polymer was used as the first water-soluble polymer so that colloidal silica having an average primary particle diameter of 90 nm was added in an amount of 1.5% by mass relative to the total amount of the polishing composition. Polyvinylpyrrolidone having a weight average molecular weight of 10000 as a second water-soluble polymer was added to water as a dispersion medium so as to be added in an amount of 0.00300% by mass relative to the total amount of the polishing composition so as to be added in an amount of 0.00300% by mass with respect to the total amount. , A mixed solution was obtained.

Then, to the obtained liquid mixture, ammonia was added so that the pH was 10.4, followed by stirring and mixing at room temperature (25°C) for 30 minutes to prepare a polishing composition. In the polishing composition, the ratio (W1/W2) of the content rate (W1) of the first water-soluble polymer and the content rate (W2) of the second water-soluble polymer is 1.

The pH of the polishing composition (liquid temperature: 25°C) was confirmed with a pH meter (Horiba Seisakusho, model number: LAQUA).

(Example 2)

The addition amounts of polyvinylpyrrolidone having a weight average molecular weight of 40000 and polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition were respectively set to 0.00200% by mass. Except for this, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 3)

Colloidal silica having an average primary particle diameter of 70 nm was used instead of colloidal silica having an average primary particle diameter of 90 nm. The addition amounts of polyvinylpyrrolidone having a weight average molecular weight of 40000 and polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition were respectively set to 0.00025% by mass. Further, instead of ammonia, potassium hydroxide was added so that the pH became 10.7. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 4)

Instead of polyvinylpyrrolidone having a weight average molecular weight of 40000, polyvinylpyrrolidone having a weight average molecular weight of 100000 was used. Except for this, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 5)

Colloidal silica having an average primary particle diameter of 70 nm was used instead of colloidal silica having an average primary particle diameter of 90 nm. The addition amount of polyvinylpyrrolidone having a weight average molecular weight of 40000 with respect to the total amount of the polishing composition was set to 0.00050% by mass. The addition amount of the polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition was set to 0.00005% by mass. The ratio (W1/W2) is 10. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 6)

Colloidal silica having an average primary particle diameter of 70 nm was used instead of colloidal silica having an average primary particle diameter of 90 nm. The addition amount of polyvinylpyrrolidone having a weight average molecular weight of 40000 with respect to the total amount of the polishing composition was set to be 0.00005% by mass. The addition amount of the polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition was set to 0.00050% by mass. The ratio (W1/W2) is 1/10. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 7)

Colloidal silica having an average primary particle diameter of 70 nm was used instead of colloidal silica having an average primary particle diameter of 90 nm. The addition amount of polyvinylpyrrolidone having a weight average molecular weight of 40000 with respect to the total amount of the polishing composition was set to be 0.00005% by mass. The addition amount of the polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition was set to 0.00005% by mass. The ratio (W1/W2) is 1. Further, ammonia was added in an amount of 0.194% by mass based on the total amount of the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.3. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Example 8)

Potassium hydroxide was added instead of ammonia. Except for these points, it carried out similarly to Example 7, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7.

(Example 9)

Polyvinylpyrrolidone having a weight average molecular weight of 40000 as the first water-soluble polymer was used as the first water-soluble polymer so that colloidal silica having an average primary particle diameter of 70 nm was added in an amount of 1.5% by mass relative to the total amount of the polishing composition. Branched alkyl as an erosion inhibitor so that the addition amount of 0.00005% by mass relative to the total amount, polyvinylpyrrolidone having a weight average molecular weight of 10000 as the second water-soluble polymer, and 0.00005% by mass relative to the total amount of the polishing composition. Sodium benzenesulfonate (C9-17) was added to water as a dispersion medium so as to add 0.0005% by mass to the total amount of the polishing composition to obtain a mixed solution.

Then, to the obtained mixture, potassium hydroxide was added in an amount equal to 0.194% by mass with respect to the total amount of the polishing composition, and stirred and mixed for 30 minutes at room temperature (25°C) to prepare a polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7. In the polishing composition, the ratio (W1/W2) of the content rate (W1) of the first water-soluble polymer and the content rate (W2) of the second water-soluble polymer is 1.

(Example 10)

Sodium dodecylbenzenesulfonate was used as an erosion inhibitor. Except for this point, it carried out similarly to Example 9, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7.

(Example 11)

As an erosion inhibitor, polyoxyethylene (n=45-55) allylphenyl ether phosphate amine salt was used. Except for this point, it carried out similarly to Example 9, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7.

(Example 12)

As an erosion inhibitor, polyoxyethylene (n=8) styrenated phenyl ether ammonium sulfate was used. Except for this point, it carried out similarly to Example 9, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7.

(Example 13)

As an erosion inhibitor, creatinine was added in an amount of 0.1% by mass relative to the total amount of the polishing composition. Except for this point, it carried out similarly to Example 9, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.7.

(Example 14)

Arginine was added as an erosion inhibitor so as to add 0.1% by mass to the total amount of the polishing composition. Except for these points, it carried out similarly to Example 9, and prepared the polishing composition. When the pH of the obtained polishing composition was confirmed, it was 10.8.

(Comparative Example 1)

No polyvinylpyrrolidone was added. Potassium hydroxide was added instead of ammonia so that the pH became 10.7. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Comparative Example 2)

No polyvinylpyrrolidone was added. Except for this, it carried out similarly to Example 1, and prepared the polishing composition.

(Comparative Example 3)

The addition amount of polyvinylpyrrolidone having a weight average molecular weight of 40000 with respect to the total amount of the polishing composition was set to 0.01000% by mass. Further, polyvinylpyrrolidone having a weight average molecular weight of 10000 was not added. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Comparative Example 4)

The addition amount of the polyvinylpyrrolidone having a weight average molecular weight of 10000 with respect to the total amount of the polishing composition was set to 0.00250% by mass. In addition, polyvinylpyrrolidone having a weight average molecular weight of 40000 was not added. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Comparative Example 5)

The addition amount of polyvinylpyrrolidone having a weight average molecular weight of 40000 with respect to the total amount of the polishing composition was set to 0.00250% by mass. Further, polyvinylpyrrolidone having a weight average molecular weight of 10000 was not added. Except for these points, it carried out similarly to Example 1, and prepared the polishing composition.

(Comparative Example 6)

Polyvinylpyrrolidone having a weight average molecular weight of 300000 was added instead of polyvinylpyrrolidone having a weight average molecular weight of 40000. Other than this, it carried out similarly to Example 1, and prepared the polishing composition.

<Measurement of polishing speed>

Using each of the obtained polishing compositions, a film containing a pattern made of a polysilicon film doped with nothing (hereinafter referred to as ``Non-Doped poly-Si film'') and a polysilicon film doped with phosphorus (hereinafter, (Referred to as "Doped poly-PTW film"), a silicon oxide film, and a silicon nitride film were subjected to CMP polishing, and the polishing rate was investigated.

(Wafer for grinding speed measurement)

The measurement of the polishing rate of each film was performed using the wafer for CMP evaluation shown below.

For polishing non-doped poly-Si film: A blanket wafer (300 mm) in which a 5,000 Å-thick polysilicon film is formed on the surface of a silicon wafer, manufactured by Advance Materials Technologies.

For polishing doped poly-PTW film: 854 mask pattern, a silicon nitride film having a thickness of 1000 Å is formed on a silicon wafer, a trench having a depth of 800 Å is formed, and then a poly- doped with phosphorus (phosphorus concentration is 0.1% by mass) and has a thickness of 2000 Å. Wafer (300 mm) in which an Si film is formed to fill in irregularities, manufactured by Advantech Co., Ltd.

For polishing a silicon oxide film: A blanket wafer (300 mm) in which a silicon oxide film (TEOS film) having a thickness of 10,000 Å is formed on the surface of a silicon wafer, manufactured by Advantech Co., Ltd.

For polishing a silicon nitride film: A blanket wafer (300 mm) in which a 3,500 angstrom-thick silicon nitride film (SiN film) is formed on the surface of a silicon wafer, manufactured by Advanced Materials Technologies, Inc.

(Polishing device and polishing conditions)

The polishing apparatus and polishing conditions used were as follows.

Polishing device: Applied Materials, 300mm CMP single-sided polishing device, Reflexion LK

Pad: Nitta Haas Co., Ltd. Rigid Polyurethane Pad IC1010

Polishing pressure: 2.2psi

Grinding plate rotation speed: 73rpm

Carrier rotation speed: 67rpm

Supply of polishing composition: flow through

Polishing composition supply amount: 200ml/min

Polishing time: 60 seconds

The value obtained by subtracting the film thickness (Å) of each film after polishing from the film thickness (Å) before polishing was divided by the polishing time (min), and the obtained calculated value was taken as the removal rate (RR).

The film thickness (Å) of each film before and after polishing was determined by an optical interference type film thickness measuring apparatus (KLA-Tencor, Ltd. model number: ASET-f5x).

<Polishing test>

Using each of the obtained polishing compositions, a pattern including a silicon nitride film is formed on a silicon wafer through an oxide film, and a polishing object on which a polysilicon film is formed is polished by the CMP method to form a wiring pattern including a polysilicon film. The following polishing test was performed.

As shown in FIG. 1, a pattern 3 including a silicon nitride film is formed on a silicon wafer 1 through an oxide film 2 on a silicon wafer 1, and a polysilicon film 4 is formed thereon. Formed. The thickness T1 of the pattern 3 including the silicon nitride film is 1000 Å, the line width H1 is 10 µm or 0.25 µm, and the interval H2 is 10 µm or 0.25 µm. Further, the thickness T2 of the polysilicon film 4 is 2000 angstroms.

When ideal polishing is performed on the object 10 to be polished, the polysilicon film 4 does not remain on the pattern 3 including the silicon nitride film, and the upper surface of the pattern 3 is exposed, and the polysilicon film 4 is exposed. A wiring pattern 41 including a silicon layer is formed, and a linear pattern 31 including a silicon nitride layer is present between adjacent wiring patterns 41. 2 is a plan view showing this state.

(Polishing device and polishing conditions)

The polishing apparatus and polishing conditions used were as follows.

Polishing device: Applied Materials, 300mm CMP single-sided polishing device, Reflexion LK

Pad: Nitta Haas Co., Ltd. Rigid Polyurethane Pad IC1010

Polishing pressure: 2.2psi

Grinding plate rotation speed: 73rpm

Carrier rotation speed: 67rpm

Supply of polishing composition: flow through

Polishing composition supply amount: 200ml/min

Polishing time: 15 seconds

(Performance evaluation)

The surface condition of the object to be polished after the polishing test was observed with an atomic force microscope (trade name WA-1300, manufactured by Hitachi Genki Fine Tech Co., Ltd.), and the remaining condition of the polysilicon film 4 to be cut was investigated. The amount of dishing of the wiring pattern 41 having a width of 10 µm and the amount of erosion of the linear pattern 31 having a width of 0.25 µm were measured.

The remaining state of the polysilicon film 4 to be cut was evaluated as follows.

◎: A state in which no polysilicon film remains on the object to be polished (for example, the state of FIG. 2)

○: A state in which there is some remaining polysilicon film on the object to be polished, but there is no problem (for example, the state of Fig. 3)

×: A state in which there is a problem with many remaining polysilicon films in the object to be polished (for example, the state of FIG. 4)

The measured values of the obtained polishing rates and the results of the polishing tests are shown in Table 1 together with the configuration of each polishing composition.

In the case of polishing using the respective polishing compositions of Examples 1 to 4, 6, 8 to 10, and 12 to 14, there was no remaining polysilicon film 4 to be cut, and the state shown in FIG. 1 is marked with ``◎''). In addition, the amount of dishing of the wiring pattern 41 was 161 Å or less, which is lower than 173 Å of Comparative Example 1, and the erosion amount of the linear pattern 31 was 88 Å or less, which is lower than 132 Å of Comparative Example 1.

In the case of polishing using the polishing composition of Examples 5, 7, 11, a part of the polysilicon film 4 to be cut remains, but most of the pattern 31 including a silicon nitride film between the wiring patterns 41 In the exposed state (for example, the state of FIG. 3), there was no problem (indicated by "○" in Table 1). In addition, the dishing amount of the wiring pattern 41 was 157 Å, which is lower than 173 Å of Comparative Example 1, and the erosion amount of the linear pattern 31 was 87 Å or less, which is lower than 132 Å of Comparative Example 1.

In the case of polishing using each of the polishing compositions of Comparative Examples 1, 2, 4, and 5, there was no remaining polysilicon film 4 to be cut, and it was in the state shown in FIG. Indication), in Comparative Example 1, the amount of dishing of the wiring pattern 41 was high at 173 angstroms, and the amount of erosion of the linear pattern 31 was also high at 132 angstroms. In Comparative Example 2, the amount of erosion of the linear pattern 31 was as high as 133 Å. In Comparative Example 4, the amount of erosion of the linear pattern 31 was as high as 98 Å. In Comparative Example 5, the amount of erosion of the linear pattern 31 was as high as 127 Å.

In the case of polishing using the respective polishing compositions of Comparative Example 3 and Comparative Example 6, most of the polysilicon film 4 to be cut remains, for example, as shown in FIG. 4, between the wiring patterns 41 There were also many portions in which the pattern 31 including the silicon nitride film was not exposed at all in the entire length direction of the wiring (indicated by "x" in Table 1).

From the above results, it was found that in the polishing compositions of Examples 1 to 14, not only the effect of reducing the remaining polysilicon film to be cut, but also the effect of suppressing dishing and erosion was obtained. On the other hand, in the polishing compositions of Comparative Examples 1 to 6, neither effect was obtained. In addition, in the polishing compositions of Examples 1 to 14, the polishing rate of the polysilicon film was 2256 to 2903 Å/min, and the polishing of the polysilicon film by the polishing compositions of Comparative Examples 1 and 2 that did not contain polyvinylpyrrolidone It was about the same as the speed (2432-2646 Å/min).

In addition, when comparing the polishing compositions of Example 7 and Example 8 in which only the types of the basic compounds contained were different, polishing using the polishing composition of Example 8 containing potassium hydroxide was an Example containing ammonia. Compared with polishing using the polishing composition of 7, the residual reduction effect of the polysilicon film 4 to be cut is higher, and the amount of dishing of the wiring pattern 41 and the amount of erosion of the linear pattern 31 are also less. From this result, it can be seen that as the basic compound, it is more preferable to use potassium hydroxide than ammonia.

In addition, when comparing the polishing compositions of Examples 9 to 14 with other examples 8 and 9 to 14 whether or not they contain an erosion inhibitor, polishing using the polishing compositions of Examples 9 to 14 containing an erosion inhibitor On the other hand, it can be seen that the amount of erosion can be further reduced compared to the case of polishing using the polishing composition of Example 8 which does not contain an erosion inhibitor.

10: object to be polished
1: silicon wafer
2: oxide film
3: Pattern including a silicon nitride film
4: polysilicon film
41: wiring pattern including polysilicon film
31: linear pattern including silicon nitride film

Claims (12)

Silica abrasive grains,
A first water-soluble polymer comprising a polymer compound containing a lactam ring and having a weight average molecular weight of less than 300,000,
A second water-soluble polymer comprising a polymer compound containing a lactam ring, and having a weight average molecular weight smaller than that of the first water-soluble polymer,
A basic compound,
the water
Polishing composition comprising. The method of claim 1,
The first water-soluble polymer and the second water-soluble polymer are homopolymers composed of a monomer containing a compound containing a lactam ring, or a monomer containing a compound containing a lactam ring and a compound not containing a lactam ring. A polishing composition that is a copolymer composed of monomers. The method of claim 2,
A polishing composition comprising at least one selected from the group consisting of vinylpyrrolidone, vinyl caprolactam, vinylvalerolactam, vinyllaurolactam, and vinylpiperidone as a monomer containing the compound containing the lactam ring . The method of claim 2,
As the homopolymer, a polishing composition comprising at least one selected from the group consisting of polyvinylpyrrolidone, polyvinyl caprolactam, polyvinylvalerolactam, polyvinyllaurolactam, and polyvinyl piperidone. The method of claim 1,
The first water-soluble polymer and the second water-soluble polymer are polyvinylpyrrolidone polishing composition. The method according to any one of claims 1 to 5,
A polishing composition wherein the total content of the first water-soluble polymer and the second water-soluble polymer is 0.05% by mass or less. The method according to any one of claims 1 to 6,
A polishing composition in which a ratio (W1/W2) of the content rate (W1) of the first water-soluble polymer and the content rate (W2) of the second water-soluble polymer is 1/15 or more and 15/1 or less. The method according to any one of claims 1 to 7,
A polishing composition further comprising an erosion inhibitor comprising a surfactant or a compound having a guanidino group. The method of claim 8,
The surfactant is an anionic surfactant, a polishing composition. The method of claim 8,
The polishing composition wherein the compound having a guanidino group is creatinine or arginine. A polishing method comprising a step of polishing an object to be polished including a film containing a silicon material having a silicon-silicon bond using the polishing composition according to any one of claims 1 to 10. Using the polishing composition according to any one of claims 1 to 10, a polishing object in which a film containing a silicon material having a silicon-silicon bond is formed on a pattern including an insulating film is polished by a CMP method, and the above A polishing method comprising a step of forming a wiring pattern containing a silicon material.

Images