Polishing composition and surface treatment method

Abstract

To provide means for effectively removing hafnium oxide.SOLUTION: A polishing composition contains (a) an anionic abrasive, (b) a nitrogen-containing additive, and (c) a dispersing medium, wherein the pH of the polishing composition is 2 or more and less than 5, and the (b) nitrogen-containing additive contains at least one selected from the group consisting of the following (i), the following (ii), and the following (iii); (i) a compound selected from the group consisting of a guanidine compound having a specific structure, an amidine compound having a specific structure, and salts thereof; (ii) a cyclic amino acid; and (iii) a sulfonic acid compound having an amino group.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a polishing composition and a surface treatment method using the polishing composition. [Background technology]

[0002] In the current semiconductor industry, the development of semiconductor manufacturing process technology is constantly progressing. Chemical mechanical polishing (CMP) technology for planarizing the surface of a semiconductor is widely applied to the semiconductor manufacturing process. An example of CMP is a method of planarizing the surface of a polishing object such as a semiconductor substrate using a polishing composition (slurry) containing abrasive grains such as silica, alumina, ceria, and additives such as an anticorrosive agent and a surfactant. Examples of the polishing object include silicon, polysilicon, silicon oxide film (silicon oxide), silicon nitride, metal, metal oxide, metal nitride, and the like.

[0003] Various polishing compositions suitable for each object to be polished have been proposed so far.

[0004] Patent Document 1 discloses a polishing composition used for polishing an object to be polished, including a silicon nitride film. The polishing composition contains abrasive grains, an anionic surfactant, and a dispersion medium, and has a pH of less than 7. The polishing composition can polish an object to be polished, including a silicon nitride film, at a high polishing rate and reduce the amount of particle residue on the object to be polished.

[0005] Patent Document 2 discloses a polishing composition capable of polishing silicon nitride at a higher speed. The polishing composition contains colloidal silica having an organic acid fixed thereto, and has a pH of 6 or less.

[0006] US Patent No. 5,999,333 discloses a composition for chemical mechanical polishing of metal and dielectric structures with high copper removal rates. The composition contains a cationically modified silica sol and an oxidizing agent, and has a pH of 2.5 to 6. The composition can achieve high metal removal rates and high metal:barrier layer selectivity.

[0007] Patent Document 4 discloses a polishing liquid capable of improving the polishing rate of a ruthenium layer. The polishing liquid contains an oxidizing agent, abrasive particles, water, and a guanidine compound or a salt thereof. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2020-26473 A [Patent Document 2] JP 2012-40671 A [Patent Document 3] JP 2003-224092 A [Patent Document 4] JP 2013-179303 A Summary of the Invention [Problem to be solved by the invention]

[0009] Hafnium oxide has a high dielectric constant and is used as an insulating film material for semiconductors. In addition, since hafnium oxide has been found to have ferroelectric properties, it has been attracting attention for its application to semiconductors, and it is expected to improve the polishing speed of hafnium oxide films in semiconductor manufacturing. The polishing compositions described in the above patent documents can achieve high polishing speeds for silicon nitride, copper, or ruthenium, but there is no disclosure or suggestion of a polishing composition used for polishing hafnium oxide films, and the demands of users cannot be met. [Means for solving the problem]

[0010] In view of the above, an object of the present invention is to provide a means for effectively removing hafnium oxide.

[0011] As a result of extensive research, the present inventors have found that the above problems can be solved by the following embodiments of the present invention (which are merely illustrative and not limiting).

[0012] The polishing composition according to the first embodiment of the present invention contains (a) an anionic abrasive, (b) a nitrogen-containing additive, and (c) a dispersion medium. The pH is greater than or equal to 2 and less than 5. The (b) nitrogen-containing additive is a polishing composition containing at least one selected from the group consisting of (i), (ii), and (iii), where (i), (ii), and (iii) are as follows:

[0013] (i) A compound selected from the group consisting of a guanidine compound represented by the following formula (I), an amidine compound represented by the following formula (II), and a salt thereof;

[0014] [ka]

[0015] [ka]

[0016] During the ceremony, R 1 , R 2 , R 3 , R 4 , R 11 and R 12 are each independently a hydrogen atom, a cyano group, a nitro group, a nitroso group, an amino group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group, or a -C(=O)-O-alkyl group, R 6is a hydrogen atom, a cyano group, a nitro group, a nitroso group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group or a -C(=O)-O-alkyl group, the aryl group or the heterocyclic group may be optionally substituted with one or more groups independently selected from a nitro group, a nitroso group, an amino group, or an alkyl group; R 5 each independently represents a hydrogen atom, an alkyl group, or an alkoxy group; (ii) cyclic amino acids; (iii) Sulfonic acid compounds having an amino group.

[0017] The polishing composition according to the second embodiment of the present invention is 1 , R 2 and the above R 6 are each independently a hydrogen atom, an alkyl group, or an alkoxy group.

[0018] The polishing composition of the third embodiment of the present invention is the polishing composition of the first or second embodiment, in which the (b) nitrogen-containing additive is a guanidine compound represented by formula (I), an amidine compound represented by formula (II), or a salt thereof, and the salt is a carbonate, hydrochloride, sulfate, phosphate, or nitrate.

[0019] In the polishing composition according to a fourth embodiment of the present invention, the nitrogen-containing additive (b) is a guanidine compound represented by the formula (I), and the R 1 and the above R 2 and each independently represent a hydrogen atom, an alkyl group, or an alkoxy group.

[0020] A polishing composition according to a fifth embodiment of the present invention is the polishing composition according to the first or second embodiment, in which the (ii) cyclic amino acid has a structure represented by the following formula (III):

[0021] [ka]

[0022] During the ceremony, R 7 is a hydrogen atom, an alkyl group, or an alkoxy group, and R 8 Ha-(CH2) p -Q, p is 0, 1 or 2, and Q is an aryl or heterocyclic group, which is optionally substituted with one or more -OH or one or more hydroxyalkyl groups; or R 7 , R 8 and the carbon atom and nitrogen atom bonded thereto together form a 5- to 6-membered heterocycle.

[0023] A polishing composition according to a sixth embodiment of the present invention is the polishing composition according to the first, second, or fifth embodiment, in which the (ii) cyclic amino acid is proline, tryptophan, or histidine.

[0024] The polishing composition of the seventh embodiment of the present invention is the polishing composition of the first, second, fifth, or sixth embodiment, in which the (iii) sulfonic acid compound having an amino group is a sulfonic acid compound having a primary amide group, a secondary amide group, or a tertiary amide group.

[0025] The polishing composition according to an eighth embodiment of the present invention is the polishing composition according to the first, second, fifth, sixth, or seventh embodiment, in which the (iii) sulfonic acid compound having an amino group has a structure represented by the following formula (IV):

[0026] [ka]

[0027] During the ceremony, n is 1, 2, 3 or 4; R 9 and R 10 are each independently a hydrogen atom, an amino group, an aminoalkyl group, an alkyl group, or a hydroxyalkyl group; or R 9 and R 10 form a 5- or 6-membered heterocycle together with the nitrogen atom bonded thereto, and the 5- or 6-membered heterocycle may be substituted with one or more -OH groups or one or more hydroxyalkyl groups, as necessary.

[0028] A polishing composition according to a ninth embodiment of the present invention is the polishing composition according to any one of the first to eighth embodiments, in which the anionic abrasive (a) is a surface-modified colloidal silica.

[0029] A polishing composition according to a tenth embodiment of the present invention is the polishing composition according to any one of the first to ninth embodiments, in which the (c) dispersion medium is water.

[0030] The polishing composition according to an eleventh embodiment of the present invention is the polishing composition according to any one of the first to tenth embodiments, further comprising (d) a surfactant.

[0031] A polishing composition according to a twelfth embodiment of the present invention is the polishing composition according to the eleventh embodiment, in which the (d) surfactant is polyether.

[0032] The polishing composition of the 13th embodiment of the present invention is the polishing composition of the 11th or 12th embodiment, in which the (d) surfactant is at least one selected from the group consisting of polyethylene glycol, polypropylene glycol, polyglycerol, and copolymers thereof.

[0033] The polishing composition according to the fourteenth embodiment of the present invention is a polishing composition according to any one of the first to thirteenth embodiments, in which the amount (content) of the anionic abrasive (a) used relative to the total mass of the polishing composition is 0.1 to 15 mass %.

[0034] The polishing composition of the 15th embodiment of the present invention is a polishing composition according to any one of the 1st to 14th embodiments, in which the amount (content) of the (b) nitrogen-containing additive used relative to the total mass of the polishing composition is 0.005 to 5 mass %.

[0035] The surface treatment method according to the sixteenth embodiment of the present invention is a surface treatment method including a step of performing surface treatment on an object to be treated using a polishing composition according to any one of the first to fifteenth embodiments.

[0036] A surface treatment method according to a seventeenth embodiment of the present invention is the surface treatment method according to the sixteenth embodiment, in which the object to be treated contains hafnium oxide.

[0037] The surface treatment method according to the eighteenth embodiment of the present invention is the surface treatment method according to the sixteenth or seventeenth embodiment, in which the object to be treated contains hafnium oxide and a silicon-based material.

[0038] A surface treatment method according to a 19th embodiment of the present invention is a surface treatment method according to any one of the 16th to 18th embodiments, in which the surface treatment is at least one selected from a planarization treatment, a selective removal treatment, and a cleaning treatment.

[0039] The surface treatment apparatus according to the 20th embodiment of the present invention is a surface treatment apparatus including a mechanism for performing surface treatment on an object to be treated using a polishing composition according to any one of the first to fifteenth embodiments.

[0040] A surface treatment apparatus according to a twenty-first embodiment of the present invention is the surface treatment apparatus according to the twentieth embodiment, in which the object to be treated contains hafnium oxide.

[0041] A surface processing apparatus according to a twenty-second embodiment of the present invention is the surface processing apparatus according to the twentieth or twenty-first embodiment, in which the object to be processed contains hafnium oxide and a silicon-based material.

[0042] The surface treatment device of the 23rd embodiment of the present invention is a surface treatment device according to any one of the 20th to 22nd embodiments, in which the surface treatment is at least one selected from a planarization treatment, a selective removal treatment, and a cleaning treatment.

[0043] A semiconductor manufacturing method according to a twenty-fourth embodiment of the present invention is a semiconductor manufacturing method including a step of carrying out a surface treatment method according to any one of the sixteenth to nineteenth embodiments.

[0044] A semiconductor manufacturing facility according to a twenty-fifth embodiment of the present invention is a semiconductor manufacturing facility including a surface treatment device according to any one of the twentieth to twenty-third embodiments.

[0045] Use according to the 26th embodiment of the present invention is use of the polishing composition according to any one of the first to fifteenth embodiments for surface treatment.

[0046] The use according to a 27th embodiment of the present invention is the use according to the 26th embodiment, in which the object to be treated by the surface treatment contains hafnium oxide.

[0047] The use according to the twenty-eighth embodiment of the present invention is the use according to the twenty-sixth or twenty-seventh embodiment, in which the object to be treated by the surface treatment includes hafnium oxide and a silicon-based material.

[0048] The use according to the 29th embodiment of the present invention is a use according to any one of the 26th to 28th embodiments, in which the surface treatment is at least one selected from a planarization treatment, a selective removal treatment, and a cleaning treatment.

[0049] However, the present invention is not limited to only the first to twenty-ninth embodiments. Although the embodiments of the present invention have been illustrated above, it is clear that the scope of the present invention should be interpreted by the appended claims. Effect of the Invention

[0050] According to the present invention, a polishing composition and a surface treatment method capable of effectively removing hafnium oxide can be provided. In some embodiments, a polishing composition and a method capable of selectively removing hafnium oxide from silicon-based materials (polysilicon, silicon-germanium (SiGe), silicon oxide produced from tetraethyl orthosilicate (TEOS) in the industry, and the like) can be provided.

[0051] Specifically, by performing polishing using the polishing composition of these embodiments, hafnium oxide can be selectively removed from silicon-based materials. In a preferred embodiment, the removal rate of silicon-based materials can be further slowed down, so that the selectivity ratio of hafnium oxide / silicon-based materials can be improved. Furthermore, since the removal rate of silicon-based materials can be significantly slowed down, it is expected that damage to silicon-based materials can be reduced as much as possible. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0052] Hereinafter, the embodiment of the present invention will be described in detail. In this specification, "X to Y" indicating a range means "X or more and Y or less". When "X to Y" are described multiple times, for example, when "X1 to Y1 or X2 to Y2" is described, the disclosure of each numerical value as the upper limit, the disclosure of each numerical value as the lower limit, and the combination of the upper limit and lower limit are all disclosed (that is, they are legal grounds for correction). Specifically, correction with X1 or more, correction with Y2 or less, correction with X1 or less, correction with Y2 or more, correction with X1 to X2, and correction with X1 to Y2 must all be considered legal. In addition, unless otherwise specified, the operation and measurement of physical properties are performed under the conditions of room temperature (20 to 25°C) / relative humidity 40 to 50% RH.

[0053] <Polishing composition> One aspect of the present invention relates to a polishing composition comprising (a) an anionic abrasive, (b) a nitrogen-containing additive, and (c) a dispersion medium, and having a pH of 2 or more and less than 5. In this aspect, the nitrogen-containing additive (b) comprises at least one selected from the group consisting of the following (i), (ii), and (iii):

[0054] (i) A compound selected from the group consisting of a guanidine compound represented by the following formula (I), an amidine compound represented by the following formula (II), and a salt thereof;

[0055] [ka]

[0056] [ka]

[0057] During the ceremony, R 1 , R 2 , R 3 , R 4 , R 11 and R 12are each independently a hydrogen atom, a cyano group, a nitro group, a nitroso group, an amino group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group, or a -C(=O)-O-alkyl group, R 6 is a hydrogen atom, a cyano group, a nitro group, a nitroso group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group or a -C(=O)-O-alkyl group, the aryl group or the heterocyclic group is optionally substituted with one or more groups independently selected from a nitro group, a nitroso group, an amino group, or an alkyl group; R 5 each independently represents a hydrogen atom, an alkyl group, or an alkoxy group; (ii) cyclic amino acids; (iii) Sulfonic acid compounds having an amino group.

[0058] According to this aspect, a polishing composition and a surface treatment method capable of effectively removing hafnium oxide can be provided. In some embodiments, a polishing composition and a method capable of selectively removing hafnium oxide from silicon-based materials (polysilicon, silicon-germanium (SiGe), silicon oxide produced from tetraethyl orthosilicate (TEOS) [in the industry, this material is called "TEOS." In this specification, "TEOS" has this meaning], etc.) can be provided.

[0059] Specifically, by performing polishing using the polishing composition of these embodiments, hafnium oxide can be selectively removed from silicon-based materials. In a preferred embodiment, the removal rate of silicon-based materials can be further slowed down, so that the selectivity ratio of hafnium oxide / silicon-based materials can be improved. Furthermore, since the removal rate of silicon-based materials can be significantly slowed down, it is expected that damage to silicon-based materials can be reduced as much as possible.

[0060] [(a) Anionic abrasive] The polishing composition according to this embodiment includes an anionic abrasive. An anionic abrasive is an abrasive that is negatively charged and exhibits a negative potential value (mV) in a zeta potential plot. In this specification, an anionic abrasive may be an abrasive that exhibits a negative potential value (mV) at any pH in a zeta potential plot. An anionic abrasive can be formed by adding an anionic group onto the surface of a nonionic abrasive. This modification to produce an anionic abrasive may be by chemical bonding or by physically forming a plurality of self-assembled monolayers on the surface of the abrasive, or by physically adsorbing an anionic group onto the surface of the abrasive.

[0061] The anionic abrasive used in the polishing composition according to some embodiments preferably exhibits a zeta potential of -5 mV or less at pH 7 or less (at all pH levels of pH 7 or less). From the viewpoint of improving the polishing rate, the zeta potential of the anionic abrasive is preferably -10 mV or less at pH 7 or less (at all pH levels of pH 7 or less), more preferably -20 mV or less, even more preferably -30 mV or less, and particularly preferably -40 mV or less. In addition, from the viewpoint of reducing defects, the zeta potential of the anionic abrasive is preferably -70 mV or more at pH 7 or less (at all pH levels of pH 7 or less), more preferably -60 mV or more, and even more preferably -55 mV or more.

[0062] The anionic abrasive used in the polishing composition according to some embodiments preferably exhibits a zeta potential of -5 mV or less in the polishing composition. The anionic abrasive preferably exhibits a zeta potential of -5 mV or less in the polishing composition. From the viewpoint of improving the polishing rate, the zeta potential of the anionic abrasive is preferably -10 mV or less in the polishing composition, more preferably -20 mV or less, even more preferably -30 mV or less, and particularly preferably -40 mV or less. In addition, from the viewpoint of reducing defects, the zeta potential of the anionic abrasive is preferably -70 mV or more in the polishing composition, more preferably -60 mV or more, and even more preferably -55 mV or more.

[0063] Because the anionic abrasive has a zeta potential in this range, it is possible to improve the removal rate for hafnium oxide while suppressing defects such as scratches that may occur on the surface of the object to be polished after polishing with the polishing composition.

[0064] Here, the zeta potential of the anionic abrasive in the polishing composition is calculated by subjecting the polishing composition to an ELS-Z2 manufactured by Otsuka Electronics Co., Ltd., measuring the composition at a measurement temperature of 25°C using a flow cell by the laser Doppler method (electrophoretic light scattering measurement method), and analyzing the obtained data using the Smoluchowski formula.

[0065] The zeta potential of an anionic abrasive is calculated by subjecting a test object containing the anionic abrasive to an ELS-Z2 manufactured by Otsuka Electronics Co., Ltd., measuring the sample at a measurement temperature of 25°C using a flow cell by the laser Doppler method (electrophoretic light scattering measurement method), and analyzing the obtained data using the Smoluchowski formula.

[0066] From the viewpoint of the effects of the present invention, preferred examples of anionic abrasives include, but are not limited to, cerium oxide abrasive grains, anion-modified silicon oxide abrasive grains, etc. In one embodiment of the present invention, the anionic abrasive preferably includes at least one of anion-modified silicon oxide abrasive grains and cerium oxide abrasive grains. The anionic abrasive preferably includes anion-modified silicon oxide abrasive grains, cerium oxide abrasive grains, or a combination thereof. In one embodiment of the present invention, the silicon oxide abrasive grains used to form the anion-modified silicon oxide abrasive grains preferably include colloidal silica (colloidal silica particles). When the anionic abrasive contains anionically modified silicon oxide abrasive grains, the mass proportion of the anionically modified silicon oxide abrasive grains in all abrasive particles of the anionic abrasive, i.e., the mass proportion of the anionically modified silicon oxide abrasive grains to the total mass of the anionic abrasive, is 80 mass% or more, 90 mass% or more, 95 mass% or more, 96 mass% or more, 97 mass% or more, 98 mass% or more, 99 mass% or more, or 100 mass%.

[0067] The colloidal silica that can be used may be any that is commonly used in the technical field of CMP. Examples of colloidal silica that can be used include colloidal silica produced by ion exchange using water glass (Na silicate) as a raw material, and alkoxide-processed colloidal silica. The alkoxide-processed colloidal silica is colloidal silica produced by hydrolysis and condensation reaction of alkoxysilane. The colloidal silica can be used alone or in combination of two or more kinds. The colloidal silica used in the examples described below was produced by the alkoxide process.

[0068] Since the zeta potential value of ordinary colloidal silica is close to zero under acidic conditions, silica particles do not electrically repel each other under acidic conditions and tend to aggregate.In contrast, by surface-modifying colloidal silica so that the zeta potential of colloidal silica has a relatively large positive or negative value even under acidic conditions, the colloidal silica particles strongly repel each other and disperse well even under acidic conditions, which improves the storage stability of the polishing composition.The anion-modified silicon oxide abrasive grains preferably contain surface-modified colloidal silica.

[0069] Examples of surface-modified colloidal silica that can be used include colloidal silica having an organic acid fixed on the surface, and colloidal silica having a surface doped with a metal such as aluminum, titanium, or zirconium, or an oxide of these metals.

[0070] In one embodiment of the present invention, the colloidal silica contained in the polishing composition is preferably colloidal silica having an organic acid fixed on the surface of silica particles (colloidal silica having an organic acid fixed on the surface). Colloidal silica having an organic acid fixed on the surface tends to have a larger absolute value of zeta potential in the polishing composition than ordinary colloidal silica having no organic acid fixed on the surface. Therefore, the zeta potential of the colloidal silica in the polishing composition is easily adjusted to a range of -5 mV or less. In some preferred embodiments, the anion-modified silicon oxide abrasive grains contain colloidal silica having an organic acid fixed on the surface.

[0071] The zeta potential of the colloidal silica can be controlled within a desired range, for example, by using an acid described below as a pH adjuster.

[0072] The organic acid is immobilized on the surface of the colloidal silica by chemically bonding the functional group of the organic acid to the surface of the colloidal silica. The organic acid is not immobilized on the colloidal silica by simply allowing the colloidal silica and the organic acid to coexist. Specific examples of the organic acid include sulfonic acid, carboxylic acid, sulfinic acid, and phosphonic acid. Among these, from the viewpoint of easy production, the colloidal silica having an organic acid immobilized on the surface is preferably a colloidal silica having a sulfonic acid or a carboxylic acid immobilized on the surface, and more preferably a colloidal silica having a sulfonic acid immobilized on the surface. In some preferred embodiments, the anion-modified silicon oxide abrasive grains include colloidal silica having a sulfonic acid immobilized on the surface.

[0073] Sulfonic acid can be immobilized on colloidal silica by, for example, the method described in “Sulfonic acid-functionalized silica through quantitative oxidation of thiol groups”, Chem. Commun. 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 to obtain colloidal silica having sulfonic acid immobilized on the surface. The colloidal silica having sulfonic acid immobilized on the surface used in the examples described below was produced by the above method.

[0074] Carboxylic acid can be immobilized on colloidal silica by, for example, the method described in “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, a silane coupling agent containing a photoreactive 2-nitrobenzyl ester is coupled to colloidal silica, followed by light irradiation to obtain colloidal silica having a carboxylic acid immobilized on the surface.

[0075] In some preferred embodiments, the anionic abrasive is a surface-modified colloidal silica. In some more preferred embodiments, the anionic abrasive is a colloidal silica having an organic acid immobilized on its surface. In some even more preferred embodiments, the anionic abrasive is a colloidal silica having a sulfonic acid immobilized on its surface.

[0076] The lower limit of the true specific gravity of silica (silica before surface modification in the case of surface-modified silica) constituting the silicon oxide abrasive grains is not particularly limited, but is preferably 1.5 or more, more preferably 1.6 or more, and even more preferably 1.7 or more. The polishing rate tends to increase as the true specific gravity of silica increases. From this viewpoint, silica (silica particles) having a true specific gravity of 2.0 or more (e.g., 2.1 or more) is particularly preferred. The upper limit of the true specific gravity of silica (silica before surface modification in the case of surface-modified silica) is not particularly limited, but is typically 2.3 or less, for example, 2.2 or less. The true specific gravity of silica can be measured by a liquid substitution method using ethanol as a substitution liquid. The true specific gravity is a value that can change depending on the manufacturing method of silica. The true specific gravity of silica (silica before surface modification) used in the examples described below was 1.88.

[0077] The average primary particle size of the abrasive grains contained in the anionic abrasive is not particularly limited. The average primary particle size of the abrasive grains contained in the anionic abrasive represents the average primary particle size of the abrasive grains constituting the anionic abrasive. For example, it may be appropriately selected from a range of about 5 to 200 nm, a range of about 5 to 100 nm, etc. From the viewpoint of improving the bulge elimination, the average primary particle size of the abrasive grains contained in the anionic abrasive is preferably 5 nm or more, more preferably 7 nm or more, and even more preferably 10 nm or more. In some embodiments, the average primary particle size of the abrasive grains contained in the anionic abrasive may be 15 nm or more, 20 nm or more, 25 nm or more, or 30 nm or more. In addition, from the viewpoint of preventing the occurrence of scratches, the average primary particle size of the abrasive grains contained in the anionic abrasive is usually advantageously 200 nm or less, preferably 150 nm or less, and more preferably 100 nm or less. In some embodiments, the average primary particle size of the abrasive grains contained in the anionic abrasive may be 90nm or less, 80nm or less, 70nm or less, 60nm or less, 50nm or less, 45nm or less, 40nm or less, or 39nm or less. The average primary particle size of the abrasive grains can be measured by first measuring the specific surface area of ​​the abrasive grains by BET (Brunauer-Emmett-Teller) method, and then calculating the average primary particle size of the abrasive grains based on the measured specific surface area. The calculation is also performed in the following examples.

[0078] The average secondary particle size of the abrasive grains contained in the anionic abrasive is not particularly limited. The average secondary particle size of the abrasive grains contained in the anionic abrasive represents the average secondary particle size of the abrasive grains constituting the anionic abrasive. The average secondary particle size of the abrasive grains contained in the anionic abrasive is preferably 25 nm or more, more preferably 30 nm or more, and even more preferably 35 nm or more. In some embodiments, the average secondary particle size of the abrasive grains contained in the anionic abrasive may be 40 nm or more, 45 nm or more, 50 nm or more, 55 nm or more, 60 nm or more, 65 nm or more, or 66 nm or more. As the average secondary particle size of the abrasive grains contained in the anionic abrasive increases, the polishing rate for the processing object (e.g., the processing object containing a hafnium oxide material) increases. The average secondary particle size of the abrasive grains contained in the anionic abrasive is preferably 300 nm or less, more preferably 260 nm or less, and even more preferably 220 nm or less. In some embodiments, the average secondary particle size of the abrasive grains contained in the anionic abrasive may be 200nm or less, 180nm or less, 160nm or less, 140nm or less, 120nm or less, 100nm or less, 90nm or less, 80nm or less, 75nm or less, or 74nm or less. As the average secondary particle size of the abrasive grains contained in the anionic abrasive becomes smaller, it becomes easier to obtain a polished surface with fewer scratches when polishing an object to be polished using the polishing composition. The value of the average secondary particle size of the abrasive grains can be measured by a suitable method, for example, a laser light scattering method. It was calculated in the same way in the examples described below.

[0079] The shape of the abrasive grains contained in the anionic abrasive (outer shape of the primary particles) is not particularly limited. The shape of the abrasive grains contained in the anionic abrasive (outer shape of the primary particles) represents the shape of the abrasive grains constituting the anionic abrasive (outer shape of the primary particles). The shape of the abrasive grains contained in the anionic abrasive may be spherical or non-spherical. Specific examples of non-spherical particles include, for example, a peanut shape, i.e., a peanut shell shape, a cocoon shape, a confetti shape, and other protruding shapes, and a rugby ball shape. In the examples described below, a cocoon shape was used. Using such a shape of abrasive grains has the effect of improving the polishing speed.

[0080] The average aspect ratio of the abrasive grains contained in the anionic abrasive is not particularly limited. The average aspect ratio of the abrasive grains contained in the anionic abrasive represents the average aspect ratio of the abrasive grains constituting the anionic abrasive. The average aspect ratio of the abrasive grains contained in the anionic abrasive is, in principle, 1.0 or more, and can be, for example, 1.05 or more or 1.1 or more. The increase in the average aspect ratio generally tends to improve the elimination of bumps. In addition, the average aspect ratio of the abrasive grains contained in the anionic abrasive is preferably 3.0 or less, more preferably 2.0 or less, from the viewpoint of reducing scratches and improving the stability of polishing. In some embodiments, the average aspect ratio of the abrasive grains contained in the anionic abrasive may be, for example, 1.5 or less, 1.4 or less, or 1.3 or less. The average aspect ratio of the abrasive grains contained in the anionic abrasive used in the examples described below was 1.24. The average aspect ratio of the abrasive grain is the average of values ​​obtained by taking the smallest rectangle circumscribing an image of the abrasive grain using a scanning electron microscope (manufactured by Hitachi High-Tech Corporation, product name: SU8000) and dividing the length of the long side of the rectangle by the length of the short side of the same rectangle, and can be evaluated using general image analysis software. It was calculated in the same way in the examples described later.

[0081] In some embodiments, the abrasive grains contained in the anionic abrasive (the abrasive grains constituting the anionic abrasive grains) may be, for example, one in which the volume ratio of particles having an aspect ratio of 1.2 or more to the total volume of the abrasive grains contained in the anionic abrasive grains is 50% or more. The volume ratio may be, for example, 60% or more. When the volume ratio is 50% or more, or even 60% or more, the abrasive grains contain a relatively large number of particles with a size and aspect ratio that are particularly effective for eliminating bumps, and therefore the bump elimination by the mechanical action of the abrasive grains can be further improved.

[0082] The content of anionic abrasive is not particularly limited, and can be appropriately set according to purpose. The content of anionic abrasive with respect to the total mass of polishing composition may be, for example, 0.1 mass% or more, 0.5 mass% or more, 1 mass% or more, or 1.5 mass% or more. By increasing the content of anionic abrasive, the bump-removing property generally tends to improve. In some embodiments, the content of anionic abrasive with respect to the total mass of polishing composition may be 0.2 mass% or more, 0.3 mass% or more, 0.4 mass% or more, or 0.45 mass% or more. In addition, from the viewpoint of preventing scratches and saving the amount of anionic abrasive used, in some embodiments, the content of anionic abrasive with respect to the total mass of the polishing composition may be, for example, 15 mass% or less, 10 mass% or less, 7 mass% or less, 5 mass% or less, 4 mass% or less, 3.5 mass% or less, 3 mass% or less, or 2.5 mass% or less. These contents may be preferably applied to the content in the polishing liquid (working slurry) supplied to the object to be polished, for example.

[0083] [(b) Nitrogen-containing additives] The polishing composition according to the present embodiment includes a specific nitrogen-containing additive.Surprisingly, by using the specific nitrogen-containing additive in the polishing composition according to the present embodiment, the removal rate of hafnium oxide by the polishing composition can be improved.Without being limited by theory, it is presumed that at least a part of the reason is that the unshared electron pair of the nitrogen atom in the nitrogen-containing additive is relatively stable, and it is easy to form a complex with hafnium.

[0084] Usable nitrogen-containing additives include at least one selected from the group consisting of the following (i), (ii), and (iii): (i) A compound selected from the group consisting of a guanidine compound represented by the following formula (I), an amidine compound represented by the following formula (II), and a salt thereof; (ii) cyclic amino acids; (iii) Sulfonic acid compounds having an amino group.

[0085] That is, the usable nitrogen-containing additive includes at least one selected from the group consisting of a guanidine compound represented by the following formula (I), a salt of a guanidine compound represented by the following formula (I), an amidine compound represented by the following formula (II), a salt of an amidine compound represented by the following formula (II), a cyclic amino acid, and a sulfonic acid compound having an amino group.

[0086] [ka]

[0087] [ka]

[0088] In the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 11 and R 12 are each independently a hydrogen atom, a cyano group, a nitro group (-NO2), a nitroso group (-N=O), an amino group, an aminoalkyl group (a group in which at least one hydrogen atom of an alkyl group is substituted with an amino group), an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group, or a -C(=O)-O-alkyl group; R 6 is a hydrogen atom, a cyano group, a nitro group, a nitroso group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group or a -C(=O)-O-alkyl group, the aryl group or the heterocyclic group may be optionally substituted with one or more groups independently selected from a nitro group, a nitroso group, an amino group, or an alkyl group; R 5 are each independently a hydrogen atom, an alkyl group, or an alkoxy group.

[0089] Here, "the aryl group or heterocyclic group is substituted with one or more groups independently selected from a nitro group, a nitroso group, an amino group, or an alkyl group as necessary" means that the aryl group or heterocyclic group may be substituted with at least one type of substituent selected from the group consisting of a nitro group, a nitroso group, an amino group, and an alkyl group, or may be unsubstituted, and when multiple hydrogen atoms are substituted in the aryl group or heterocyclic group, the types of the substituents substituting each hydrogen atom of the aryl group or heterocyclic group may be the same or different. The number of nitro groups, nitroso groups, amino groups, and alkyl groups substituting the aryl group or heterocyclic group is each independently 0, 1, or 2 or more. Therefore, the number of at least one type of substituent selected from the group consisting of a nitro group, a nitroso group, an amino group, and an alkyl group substituting the aryl group or heterocyclic group is 0, 1, or 2 or more.

[0090] In some embodiments, R 1 , R 2 and R 6 It is preferable that each independently represents a hydrogen atom, an alkyl group, or an alkoxy group.

[0091] In the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12 The alkyl or alkylene group moiety in the aminoalkyl group, alkyl group, alkoxy group, -C(=O)-alkyl group, and -C(=O)-O-alkyl group as R may be a straight chain alkyl group, a branched chain alkyl group, a straight chain alkylene group, or a branched chain alkylene group, and the number of carbon atoms therein is not particularly limited and is, for example, 1 to 20, preferably 1 to 10, more preferably 1 to 4, and further preferably 1 or 2. 5The alkyl group as the above and the alkyl group moiety in the alkoxy group may be a straight-chain or branched-chain alkyl group, and the number of carbon atoms therein is not particularly limited and is, for example, 1 to 20, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.

[0092] In the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12 The aryl group as may be a monocyclic aromatic hydrocarbon ring group containing 6 to 14 carbon atoms, a bicyclic aromatic hydrocarbon ring group containing 6 to 14 carbon atoms, or a tricyclic aromatic hydrocarbon ring group containing 6 to 14 carbon atoms. Examples include, but are not limited to, a phenyl group, an indenyl group, a naphthyl group, a fluorenyl group, an anthracenyl group, a phenanthrenyl group, and groups similar thereto. A phenyl group is preferred. In some embodiments, in the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12 The aryl groups as may be independently substituted or unsubstituted, and are preferably independently nitro groups and C 1-4 The alkyl group is substituted with one or more groups independently selected from alkyl groups (alkyl groups having 1 to 4 carbon atoms).

[0093] In the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12The heterocyclic group represented by R may be a saturated, partially saturated, or unsaturated 3- to 14-membered heterocyclic group composed of carbon atoms and at least one heteroatom selected from N, O, or S, and is preferably a 4- to 10-membered heterocyclic group, and more preferably a 5- or 6-membered heterocyclic group. 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12 The heterocyclic group as is not particularly limited, but preferably has 1 to 4 heteroatoms, more preferably has 1 to 3 heteroatoms, and further preferably has 1 to 2 heteroatoms. The heterocyclic group may be a monocyclic, bicyclic or tricyclic ring system, may contain a fused ring (forming a fused ring together with another heterocyclic ring or an aromatic hydrocarbon ring), and may be substituted or unsubstituted. The type of heteroatom is preferably a nitrogen atom. Examples of the aforementioned heterocyclic groups include, but are not limited to, a pyrrolyl group, a pyrazolyl group, an imidazolyl group, a pyridinyl group, a pyridazinyl group, a pyrimidinyl group, a pyrazinyl group, a pyrrolidinyl group, a piperidinyl group, and a piperazinyl group.

[0094] In some embodiments, in the above formula (I) and the above formula (II), R 1 , R 2 , R 3 , R 4 , R 6 , R 11 and R 12 The heterocyclic group as is preferably a 5- or 6-membered ring group containing 1 or 2 nitrogen atoms, and examples thereof include a pyrazolyl group and an imidazolyl group.

[0095] Examples of the salt of the guanidine compound represented by the formula (I) and the salt of the amidine compound represented by the formula (II) include carbonates, hydrochlorides, phosphates, sulfates, nitrates, hydroiodides, etc. However, since contamination of the substrate with halides, etc. is undesirable, carbonates, phosphates, nitrates, or sulfates are preferred.

[0096] In some preferred embodiments, the nitrogen-containing additive (b) is a guanidine compound represented by formula (I), an amidine compound represented by formula (II), or a salt thereof, the salt being a carbonate, hydrochloride, sulfate, phosphate, or nitrate. In some more preferred embodiments, the nitrogen-containing additive (b) is a guanidine compound represented by formula (I), and R 1 and R 2 are each independently a hydrogen atom, an alkyl group, or an alkoxy group.

[0097] Specific examples of the guanidine compound represented by the above formula (I) or its salt include guanidine and its carbonate (carbonate of guanidine, guanidine carbonate), its hydrochloride (hydrochloride of guanidine), its phosphate (phosphate of guanidine), its sulfate (sulfate of guanidine) and its nitrate (nitrate of guanidine); guanidine hydroiodide hydroiodide;acetylguanidine;aminoguanidine and its carbonate (carbonate of aminoguanidine), its hydrochloride (hydrochloride of aminoguanidine) and its sulfate (sulfate of aminoguanidine);1,3-diaminoguanidine and its hydrochloride;1-(tert-butoxycarbonyl)guanidine;dicyandiamide;1,1-dimethylguanidine and its sulfate;1,1- Examples of the guanidine compound include 1,1-diethylguanidine and its sulfate salt; 1-methyl-3-nitroguanidine; 1-(2-methyl-5-nitrophenyl)guanidine and its nitrate salt; nitroguanidine, nitrosoguanidine; octadecylguanidine and its hydrochloride salt; and 1,1,3,3-tetramethylguanidine. These may be used alone or in combination of two or more. The guanidine compound represented by the above formula (I) or its salt preferably contains at least one compound selected from the group consisting of the compounds exemplified above. Of these, from the viewpoint of improving the polishing rate of hafnium oxide, guanidine or a carbonate salt thereof (guanidine carbonate) is preferable, and from the viewpoint of improving the selectivity ratio of hafnium oxide / silicon-based material, guanidine is more preferable.

[0098] Specific examples of the amidine compound represented by the above formula (II) or its salt include acetamidine and its hydrochloride; aminoacetamidine bromate; aminoacetamidine hydrobromide; 1-amidinopyrazole and its hydrochloride. From the viewpoint of improving the polishing rate of hafnium oxide, among them, aminoacetamidine bromate, aminoacetamidine hydrobromide, and 1-amidinopyrazole are preferred, and 1-amidinopyrazole is more preferred. These may be used alone or in combination of two or more. The amidine compound represented by the above formula (II) or its salt preferably contains at least one compound selected from the group consisting of the compounds exemplified above.

[0099] In some embodiments, the (ii) cyclic amino acid that can be used as the nitrogen-containing additive can have a structure represented by formula (III):

[0100] [ka]

[0101] In the above formula (III), R 7 is a hydrogen atom, an alkyl group, or an alkoxy group, and R 8 Ha-(CH2) p -Q, p is 0, 1 or 2, and Q is an aryl group or a heterocyclic group, which may be optionally substituted with one or more -OH (hydroxyl group) or one or more -hydroxyalkyl groups (a group in which at least one hydrogen atom of an alkyl group is replaced with a hydroxyl group); or R 7 , R 8 and the carbon atom and nitrogen atom bonded thereto together form a 5- to 6-membered heterocycle (5-membered or 6-membered heterocycle).

[0102] As mentioned above, R 7 , R 7 Nitrogen atom bonded to R 8 and R 8 The carbon atoms bonded to may join together to form a 5- or 6-membered heterocycle.

[0103] R 7 is a hydrogen atom, an alkyl group or an alkoxy group, and R 8 Ha-(CH2) p When -Q, p is 0, 1 or 2, and Q is an aryl group or a heterocyclic group, said aryl group or said heterocyclic group may be unsubstituted.

[0104] In the above formula (III), R 7 The alkyl group and alkoxy group as may be linear or branched, and the number of carbon atoms therein is not particularly limited and is, for example, 1 to 20, preferably 1 to 10, and more preferably 1 to 4.

[0105] The number of carbon atoms of the aryl group as Q is not particularly limited, and is preferably 6 to 9. Examples of the aryl group as Q include phenyl, tolyl, and isopropylphenyl. The heterocyclic group as Q is not particularly limited, and may be an aliphatic heterocyclic group or an aromatic heterocyclic group. The aliphatic heterocyclic group and the aromatic heterocyclic group may each be either a monocyclic group or a condensed ring group. That is, the aliphatic heterocyclic group may be either a monocyclic group or a condensed ring group, and the aromatic heterocyclic group may be either a monocyclic group or a condensed ring group. The total number of atoms of the ring constituting the aliphatic heterocyclic group or the aromatic heterocyclic group is, for example, 3 to 15, preferably 3 to 12, more preferably 3 to 10, and even more preferably 3 to 6. The aliphatic heterocyclic group or the aromatic heterocyclic group may contain a nitrogen atom, an oxygen atom, or a sulfur atom as an atom constituting the ring in addition to carbon atoms. The number of heteroatoms is, for example, preferably 1 to 3, more preferably 1 or 2, and even more preferably 1.

[0106] In addition, the hydroxyalkyl group usable as the substituent of Q may be a straight chain or a branched chain, and the number of carbon atoms therein is not particularly limited and is, for example, 1 to 20, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.

[0107] Specific examples of the cyclic amino acid represented by the above formula (III) include phenylalanine, proline, tryptophan, tyrosine, and histidine. These may be used alone or in combination of two or more. The cyclic amino acid represented by the above formula (III) preferably contains at least one compound selected from the group consisting of the compounds exemplified above. From the viewpoint of improving the polishing rate of hafnium oxide, the cyclic amino acid is preferably proline, tryptophan, or histidine, more preferably proline or histidine, even more preferably L-proline or L-histidine, and particularly preferably L-histidine.

[0108] In some embodiments, the (iii) sulfonic acid compound having an amino group that can be used as the nitrogen-containing additive is a sulfonic acid compound having a primary, secondary or tertiary amide group (a sulfonic acid compound having a primary amide group (primary amino group, -NH2), a secondary amide group (secondary amino group, -NHR) or a tertiary amide group (tertiary amino group, -NRR'). Here, R and R' each independently represent an atom other than a hydrogen atom or an atomic group. From the viewpoint of improving the polishing rate of hafnium oxide, among them, a sulfonic acid compound having a primary amide group or a secondary amide group is preferable, and a sulfonic acid compound having a primary amide group is more preferable.

[0109] Specific examples of sulfonic acid compounds having a primary amide group include aminomethylsulfonic acid, taurine, and aminopropylsulfonic acid. Specific examples of sulfonic acid compounds having a secondary amide group include 2-methylaminoethanesulfonic acid and 2-[(2-aminoethyl)-amino]ethanesulfonic acid. Specific examples of sulfonic acid compounds having a tertiary amide group include 4-(2-hydroxyethyl) piperazine-1-ethanesulfonic acid (HEPES) and N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (BES). These sulfonic acid compounds having an amino group may be used alone or in combination of two or more. The sulfonic acid compound having an amino group preferably contains at least one compound selected from the group consisting of the compounds exemplified above.

[0110] In some embodiments, the (iii) sulfonic acid compound having an amino group that can be used as the nitrogen-containing additive has a structure represented by the following formula (IV):

[0111] [ka]

[0112] In the above formula (IV), n is 1, 2, 3 or 4.

[0113] In addition, in the above formula (IV), R 9 and R 10are each independently a hydrogen atom, an amino group, an aminoalkyl group (a group in which at least one hydrogen atom of an alkyl group is substituted with an amino group), an alkyl group, or a hydroxyalkyl group (a group in which at least one hydrogen atom of an alkyl group is substituted with a hydroxy group); R 9 and R 10 are the nitrogen atoms (R 9 and R 10 (a nitrogen atom bonded to the nitrogen atom) to form a 5- or 6-membered heterocycle (a 5- or 6-membered heterocycle), and the 5- or 6-membered heterocycle may be substituted with one or more -OH (hydroxy groups) or one or more hydroxyalkyl groups, as necessary.

[0114] R 9 and R 10 When these are taken together with the nitrogen atom to which they are bonded to form a 5- or 6-membered heterocycle, the 5- or 6-membered heterocycle may be unsubstituted.

[0115] In some embodiments, R 9 and R 10 are each independently a hydrogen atom, an aminoalkyl group, an alkyl group, or a hydroxyalkyl group; or R 9 and R 10 form a 5- or 6-membered heterocycle together with the nitrogen atom bonded thereto, and the 5- or 6-membered heterocycle may be substituted with one or more -OH (hydroxy groups) or one or more hydroxyalkyl groups, as necessary.

[0116] In the above formula (IV), R 9 and R 10 The alkyl or alkylene group portion in the aminoalkyl group, alkyl group, and hydroxyalkyl group as the above may be a linear alkyl group, a branched alkyl group, a linear alkylene group, or a branched alkylene group, and the number of carbon atoms therein is not particularly limited and is, for example, 1 to 20, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.

[0117] R 9 and R 10 When R forms a 5- to 6-membered heterocycle together with the nitrogen atom to which it is bonded, the definition of the alkylene group in the hydroxyalkyl group as the substituent is as follows: 9 and R 10 This is similar to the alkylene group in the hydroxyalkyl group as mentioned above.

[0118] R 9 and R 10 When they form a 5- or 6-membered heterocycle together with the nitrogen atom to which they are bonded, the hydroxyalkyl group as the substituent thereon preferably contains one hydroxy group. However, the number of hydroxy groups contained in the hydroxyalkyl group is not limited thereto, and may be two or more.

[0119] R 9 and R 10 When these are taken together with the nitrogen atom to which they are attached to form a 5- or 6-membered heterocycle, examples of the heterocycle include, but are not limited to, a pyrrolyl group, a pyrazolyl group, an imidazolyl group, a pyridinyl group, a pyridazinyl group, a pyrimidinyl group, a pyrazinyl group, a pyrrolidinyl group, a piperidinyl group, and a piperazinyl group.

[0120] In some preferred embodiments, in formula (IV), n is 1, 2, 3 or 4; R 9 and R 10 are each independently a hydrogen atom or C 1-4 a hydroxyalkyl group (a hydroxyalkyl group having 1 to 4 carbon atoms), or R 9and R 10 form, together with the nitrogen atom bonded thereto, a saturated 5- to 6-membered heterocycle or an unsaturated 5- to 6-membered heterocycle containing 1 to 2 nitrogen atoms (a saturated 5- to 6-membered heterocycle containing 1 to 2 nitrogen atoms or an unsaturated 5- to 6-membered heterocycle containing 1 to 2 nitrogen atoms, preferably a 5- to 6-membered saturated heterocycle containing 2 nitrogen atoms), and the saturated 5- to 6-membered heterocycle or the unsaturated 5- to 6-membered heterocycle may, as necessary, be one or more -OH or one or more C 1-4 It may be substituted with a hydroxyalkyl group (a hydroxyalkyl group having 1 to 4 carbon atoms).

[0121] In some preferred embodiments, the nitrogen-containing additive is a guanidine compound represented by formula (I) or a salt thereof, a cyclic amino acid represented by formula (III), or a sulfonic acid compound having an amino group represented by formula (IV). In some more preferred embodiments, the nitrogen-containing additive is a guanidine compound represented by formula (I), a cyclic amino acid represented by formula (III), or a sulfonic acid compound having an amino group represented by formula (IV). In some further preferred embodiments, the nitrogen-containing additive is a guanidine compound represented by formula (I), a cyclic amino acid represented by formula (III), or a sulfonic acid compound having an amino group and no hydroxyalkyl group represented by formula (IV) (a compound having a hydroxyalkyl group represented by formula (IV)). In some further preferred embodiments, the nitrogen-containing additive is a cyclic amino acid represented by formula (III) or a sulfonic acid compound having an amino group and no hydroxyalkyl group represented by formula (IV). In some particularly preferred embodiments, the nitrogen-containing additive is a cyclic amino acid represented by formula (III).

[0122] The content of nitrogen-containing additive is not particularly limited, and can be appropriately set according to purpose.The content of nitrogen-containing additive with respect to the total mass of polishing composition can be, for example, 0.005 mass% or more, 0.01 mass% or more, 0.03 mass% or more, or 0.05 mass% or more.In some embodiments, the content of nitrogen-containing additive with respect to the total mass of polishing composition can be 5 mass% or less, 1 mass% or less, 0.5 mass% or less, 0.2 mass% or less, or 0.15 mass% or less.

[0123] [(c) Dispersion medium] The polishing composition according to this embodiment contains a dispersion medium. The dispersion medium functions as a dispersion medium or solvent for dispersing or dissolving each component of the polishing composition (for example, anionic abrasives and nitrogen-containing additives, and other optional additives such as surfactants and / or pH adjusters). Examples of the dispersion medium include water and organic solvents. The dispersion medium can be used alone or in combination of two or more, but it is preferable that the dispersion medium contains water. In some preferred embodiments, the dispersion medium is water. However, from the viewpoint of preventing the inhibition of the action of each component, it is preferable to use water that contains as few impurities as possible. Specifically, pure water or ultrapure water obtained by removing impurity ions with an ion exchange resin and then removing foreign matter through a filter, or distilled water is preferable.

[0124] In some embodiments, the content of water in the dispersion medium is 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, 95% by weight or more, 96% by weight or more, 97% by weight or more, 98% by weight or more, 99% by weight or more, or 100% by weight, based on the total weight of the dispersion medium.

[0125] [(d) Surfactant] The polishing composition according to some embodiments may contain a surfactant as necessary in addition to the anionic abrasive, the nitrogen-containing additive, and the dispersion medium. The polishing composition according to some embodiments may further contain a surfactant, or may not contain a surfactant. In some embodiments, the surfactant in the polishing composition has an effect of inhibiting the polishing of silicon, so that the ratio (selectivity) of the removal rate (polishing rate) of hafnium oxide to the removal rate (polishing rate) of silicon-based materials can be further improved. In addition, the surfactant has an effect of imparting hydrophilicity to the polished surface of the polished object after polishing, so that the cleaning efficiency of the polished object after polishing can be improved and adhesion of dirt can be suppressed.

[0126] The surfactant is not particularly limited, and any known surfactant used in the field of polishing compositions can be used. Among them, nonionic surfactants are preferred. In some embodiments, the surfactant preferably contains a nonionic surfactant. Specific examples of nonionic surfactants include polyether, sorbitan fatty acid ester, glycerin fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene alkylamine, and alkyl alkanolamide. These may be used alone or in combination of two or more. The nonionic surfactant preferably contains at least one compound selected from the group consisting of the compounds exemplified above. From the viewpoint of storage stability of the polishing composition, the surfactant is preferably polyether.

[0127] Examples of polyethers include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyethylene glycol alkyl ether, polyethylene glycol alkenyl ether, alkyl polyethylene glycol, alkyl polyethylene glycol alkyl ether, alkyl polyethylene glycol alkenyl ether, alkenyl polyethylene glycol, alkenyl polyethylene glycol alkyl ether, alkenyl polyethylene glycol alkenyl ether, polypropylene glycol alkyl ether, polypropylene glycol alkenyl ether, alkyl polypropylene glycol, alkyl polypropylene glycol alkyl ether, alkyl polypropylene glycol alkenyl ether, alkenyl polypropylene glycol, alkenyl polypropylene glycol alkyl ether, alkenyl polypropylene glycol alkenyl ether, polyoxyethylene alkylene diglyceryl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene polypropylene alkyl ether, polyglycerol, and copolymers thereof. The polyethers may be used alone or in combination of two or more. The polyether preferably contains at least one compound selected from the group consisting of the compounds exemplified above. Among these polyethers, at least one selected from the group consisting of polyethylene glycol, polypropylene glycol, and polyglycerol is preferred. The surfactant is preferably at least one selected from the group consisting of polyethylene glycol, polypropylene glycol, and polyglycerol, more preferably at least one selected from the group consisting of polyethylene glycol and polypropylene glycol, and even more preferably polypropylene glycol.

[0128] According to some embodiments, the weight average molecular weight (Mw) of the polyether may be less than or equal to 100,000, less than or equal to 10,000, less than or equal to 1,000, or less than or equal to 800. In this specification, the weight average molecular weight is measured by gel permeation chromatography (GPC) using polyethylene glycol as a standard.

[0129] The upper limit of the surfactant content in the polishing composition according to some embodiments is preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.5% by mass or less, and particularly preferably 0.1% by mass or less, based on the total mass (total mass) of the polishing composition. The upper limit of the surfactant content relative to the total mass of the polishing composition is preferably 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.5% by mass or less, and particularly preferably 0.1% by mass or less. The lower limit of the surfactant content in the polishing composition according to some embodiments is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.03% by mass or more, based on the total mass (total mass) of the polishing composition. The lower limit of the surfactant content relative to the total mass (total mass) of the polishing composition is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.03% by mass or more.

[0130] [pH adjuster] The polishing composition according to some embodiments may contain a pH adjuster. By using the pH adjuster, the pH of the polishing composition can be adjusted to a desired value. As the pH adjuster, a known acidic or basic compound may be used. The pH adjuster may be used alone or in combination of two or more.

[0131] The acidic compound may be an inorganic acid or an organic acid. Examples of inorganic acids include hydrochloric acid (HCl), sulfuric acid (H2SO4), nitric acid (HNO3), hydrofluoric acid (HF), boric acid (H3BO3), carbonic acid (H2CO3), hypophosphorous acid (H3PO2), phosphorous acid (H3PO3), and phosphoric acid (H3PO4). Among these inorganic acids, preferred inorganic acids are hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid, and more preferred is nitric acid.

[0132] Examples of organic acids include 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, hydroxyacetic acid, 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, lactic acid, glyoxylic acid, and the like. Examples of organic acids include 2-furan carboxylic acid, 2,5-furandicarboxylic acid, 3-furan carboxylic acid, 2-tetrahydrofuran carboxylic acid, methoxyacetic acid, methoxyphenylacetic acid, and phenoxyacetic acid. Sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, and isethionic acid (2-hydroxyethanesulfonic acid) may also be used. Among these organic acids, preferred organic acids are monocarboxylic acids such as acetic acid; dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, maleic acid, phthalic acid, malic acid, and tartaric acid; or tricarboxylic acids such as citric acid. The organic acid is more preferably oxalic acid or maleic acid.

[0133] Examples of basic compounds include hydroxides of alkali metals, salts of alkali metals, hydroxides of Group 2 elements, salts of Group 2 elements, quaternary ammonium hydroxides, quaternary ammonium salts, ammonia, amines, etc. Examples of alkali metals include potassium and sodium. Ammonia is preferred.

[0134] The pH adjuster preferably contains at least one compound selected from the group consisting of the compounds exemplified above.

[0135] The upper limit of the pH of the polishing composition according to this embodiment is less than 5. If the pH is too high (for example, if the pH is 5 or more), the removal rate of hafnium oxide will be poor. The upper limit of the pH of the polishing composition is preferably 4.8 or less, more preferably 4.6 or less, and even more preferably 4.5 or less. The upper limit of the pH of the polishing composition may be, for example, 4.4 or less, 4.3 or less, 4.2 or less, 4.1 or less, 4.0 or less, 3.9 or less, 3.8 or less, 3.7 or less, 3.6 or less, 3.5 or less, 3.4 or less, 3.3 or less, 3.2 or less, 3.1 or less, or 3.0 or less. The lower limit of the pH of the polishing composition according to this embodiment is not particularly limited as long as it is 2 or more. However, in consideration of the safety of the manufacturing process and the burden of waste liquid treatment, the lower limit of the pH of the polishing composition is preferably 2.2 or more, more preferably 2.5 or more. The lower limit of the pH may be 2.6 or more, 2.7 or more, 2.8 or more, 2.9 or more, or 3.0 or more. The pH of the polishing composition according to this embodiment is preferably in the range of 2 or more and less than 5. In this specification, the pH refers to the pH at 25° C. The pH at 25° C. can be measured with a pH meter, and is the value after immersing an electrode in the polishing composition for 1 minute.

[0136] The content of the pH adjuster in the polishing composition is not particularly limited, and may be any content that provides a desired pH.

[0137] [Other ingredients] As long as the effect of the present invention is not impaired, the polishing composition according to some embodiments may further contain other components (representing components different from the components specifically described above in this specification). The polishing composition according to some embodiments may further contain other components, or may not contain other components. Examples of other components include organic acid salts, inorganic acid salts, preservatives, fungicides, and other well-known additives used in polishing compositions.

[0138] According to some embodiments, the content of other components is, for example, 10% by mass or less, 5% by mass or less, 4% by mass or less, 3% by mass or less, 2% by mass or less, 1% by mass or less, 0.5% by mass or less, 0.1% by mass or less, 0.05% by mass or less, 0.001% by mass or less, or 0.0005% by mass or less, based on the total mass (total mass) of the components excluding the dispersion medium.

[0139] The polishing composition according to some preferred embodiments may be substantially composed of (a) an anionic abrasive, (b) a nitrogen-containing additive, (c) a dispersion medium, and a pH adjuster. The polishing composition according to some preferred embodiments may be, for example, composed only of (a) an anionic abrasive, (b) a nitrogen-containing additive, (c) a dispersion medium, and a pH adjuster. "The polishing composition is substantially composed of X" means that the total content of X is more than 99 mass% (upper limit: 100 mass%) with respect to the total mass of the polishing composition. The polishing composition may be composed only of X (the total content = 100 mass%).

[0140] The polishing composition according to some preferred embodiments may be substantially composed of (a) an anionic abrasive, (b) a nitrogen-containing additive, (c) a dispersion medium, (d) a surfactant, and a pH adjuster. The polishing composition according to some preferred embodiments may be, for example, composed only of (a) an anionic abrasive, (b) a nitrogen-containing additive, (c) a dispersion medium, (d) a surfactant, and a pH adjuster. "The polishing composition is substantially composed of X" means that the total content of X is more than 99 mass% (upper limit: 100 mass%) with respect to the total mass of the polishing composition. The polishing composition may be composed only of X (the total content = 100 mass%).

[0141] [Form of polishing composition] The polishing composition according to the present embodiment may be a one-liquid type or a multi-liquid type such as a two-liquid type. The polishing composition according to the present embodiment may be in the form of a concentrated stock solution. In this case, the concentrated stock solution is diluted with a diluent such as water, for example, 2 to 10 times or more, and then used for surface treatment.

[0142] [Method of manufacturing the polishing composition] The method for producing the polishing composition according to this embodiment is not particularly limited. The polishing composition according to some embodiments can be produced, for example, by a method including mixing (a) an anionic abrasive, (b) a nitrogen-containing additive, (c) a dispersion medium, and optionally (d) a surfactant, optionally a pH adjuster, and optionally other components. The details of each component are as described above. In some embodiments, when the polishing composition is a multi-liquid type, including a two-liquid type, each liquid can be produced by a method including mixing the components constituting each liquid.

[0143] [Application] The polishing composition according to this embodiment is preferably used for treating a specific object. The treatment is not particularly limited, and may be, for example, a surface treatment. Therefore, another aspect of the present invention may be said to be related to the use of the polishing composition for surface treatment. In some preferred embodiments, the surface treatment is at least one selected from the group consisting of a flattening treatment, a selective removal treatment, and a cleaning treatment. In some preferred embodiments, the surface treatment is at least one selected from the group consisting of a polishing treatment, a selective removal treatment, and a cleaning treatment. In some preferred embodiments, the polishing composition is used for a polishing treatment and a selective removal treatment.

[0144] [Materials to be processed] There is no particular limitation on the object to be treated using the polishing composition according to this embodiment, and examples thereof include semiconductor materials such as wafers or substrates, or optical elements such as lenses or glass substrates. The object to be treated is preferably a material from which hafnium oxide needs to be removed, an element from which hafnium oxide needs to be removed, a material from which hafnium oxide needs to be selectively removed, or an element from which hafnium oxide needs to be selectively removed. There is no particular limitation on the components of the object to be treated, but it is preferable that the object to be treated contains hafnium oxide. In some preferred embodiments, the object to be treated contains a silicon-based material such as polysilicon, silicon germanium, and / or TEOS, and hafnium oxide. The object to be treated preferably contains hafnium oxide and at least one material selected from the group consisting of polysilicon, silicon germanium, and TEOS.

[0145] <Surface treatment method (polishing method)> Another aspect of the present invention can be said to be a surface treatment method including a step of performing a surface treatment on a treatment object using the polishing composition according to the above aspect. The surface treatment using the polishing composition according to the above aspect is not particularly limited, but may be at least one selected from the group consisting of flattening treatment, selective removal treatment, and cleaning treatment for the treatment object. The surface treatment method using the polishing composition according to the above aspect is not particularly limited, but is preferably chemical mechanical polishing. The polishing step may be a polishing step consisting of a single step, or a polishing step consisting of multiple steps. Examples of the polishing step consisting of multiple steps include a step of performing a finish polishing step after a preliminary polishing step (rough polishing step), or a step of performing one or more secondary polishing steps after a primary polishing step, and then performing a finish polishing step.

[0146] The surface treatment method according to some embodiments may be included in a semiconductor manufacturing method. Therefore, another aspect of the present invention can be said to be a semiconductor manufacturing method including a step of performing the surface treatment method according to the above aspect.

[0147] <Surface treatment equipment (polishing equipment)> Another aspect of the present invention can be said to relate to a surface treatment device that includes a mechanism for performing surface treatment on a treatment object using the polishing composition according to the above-mentioned aspect. The surface treatment device using the polishing composition according to the above-mentioned aspect is not particularly limited, and may, for example, be a device that performs at least one of the following treatments on a treatment object: planarization treatment, selective removal treatment, and cleaning treatment.

[0148] As a surface treatment device (polishing device), a general polishing device can be used that is equipped with a holder for holding a substrate or the like having an object to be polished (object to be processed) and a motor whose rotation speed can be changed, and that has a polishing platen onto which a polishing pad (polishing cloth) can be attached.

[0149] The polishing pad may be made of any material, including, without limitation, a general nonwoven fabric, polyurethane, or porous fluororesin. The polishing pad is preferably provided with grooves for accumulating the polishing composition.

[0150] There is no particular restriction on the polishing conditions. For example, the rotation speed of the polishing platen (the number of rotations of the polishing platen) is 10 to 500 rpm (60 rpm = 1 s -1 ), and the carrier rotation speed (carrier rotation number) is preferably 10 to 500 rpm (60 rpm = 1 s -1 ) is preferred, and the pressure (polishing pressure, polishing platen pressure) applied to a substrate having an object to be polished (object to be processed) is preferably 0.1 to 10 psi (1 psi = 6894.76 Pa). The method of supplying the polishing composition to the polishing pad is not particularly limited, and for example, a method of continuously supplying the polishing composition using a pump or the like is adopted. There is no limit to the amount of supply, but it is preferred that the surface of the polishing pad is always covered with the polishing composition according to the above embodiment.

[0151] After polishing, the substrate may be washed with running water, and then dried using a spin dryer or the like to remove water droplets adhering to the substrate, thereby obtaining a substrate having a treated surface.

[0152] The surface treatment apparatus (polishing apparatus) according to some embodiments may be included in a semiconductor manufacturing facility. Therefore, another aspect of the present invention can be said to relate to a semiconductor manufacturing facility including the surface treatment apparatus according to the above aspect.

[0153] <Method for selectively removing hafnium oxide> Another aspect of the present invention can be said to be a method for selectively removing hafnium oxide using the polishing composition according to the above aspect, and a preferred embodiment of the present invention is a method for selectively removing hafnium oxide from silicon-based materials.The silicon-based materials include, but are not limited to, polysilicon, silicon germanium, TEOS, etc.In some preferred embodiments, the silicon-based materials include at least one selected from the group consisting of polysilicon, silicon germanium, and TEOS.

[0154] According to the method for selectively removing hafnium oxide of this embodiment, the purpose of selectively removing hafnium oxide can be achieved while increasing the removal rate of hafnium oxide. The method for selectively removing hafnium oxide of this embodiment is not particularly limited as long as it uses the polishing composition of the above embodiment, and may be performed in combination with a known manufacturing method and / or processing method for semiconductor materials or optical elements, etc.

[0155] In some embodiments, under the conditions for measuring the polishing rate described in the Examples, the selectivity ratio of hafnium oxide / silicon-based material (polishing rate of hafnium oxide / polishing rate of silicon-based material) is, for example, 5 or more, 8 or more, 10 or more, or 12 or more, and preferably 20 or more, 50 or more, or 100 or more.

[0156] In some embodiments, under the conditions for measuring the polishing rate described in the examples, the selectivity ratio of hafnium oxide to polysilicon (polishing rate of hafnium oxide / polishing rate of polysilicon) is, for example, 5 or more, and preferably 10 or more, 20 or more, 30 or more, 50 or more, 60 or more, 70 or more, or 80 or more.

[0157] In some embodiments, under the conditions for measuring the polishing rate described in the examples, the selectivity ratio of hafnium oxide / silicon germanium (polishing rate of hafnium oxide / polishing rate of silicon germanium) is, for example, 10 or more, preferably 15 or more, 20 or more, 50 or more, 80 or more, 100 or more, or 110 or more.

[0158] In some embodiments, under the conditions for measuring the polishing rate described in the Examples, the selectivity ratio of hafnium oxide / TEOS (polishing rate of hafnium oxide / polishing rate of TEOS) is, for example, 8 or more, preferably 10 or more, 12 or more, or 20 or more.

[0159] Although the embodiments of the present invention have been described in detail, it is apparent that the same are illustrative and exemplary, not restrictive, and the scope of the present invention should be interpreted by the appended claims. EXAMPLES

[0160] The present invention will be further described below with reference to examples and comparative examples, but the scope of the present invention is not limited to the examples described below. In the examples described below, the polishing conditions are room temperature (20 to 25°C) and relative humidity 40 to 50% RH unless otherwise specified.

[0161] [Preparation of polishing composition] In Examples 1 to 14 and Comparative Examples 1 to 9, polishing compositions were prepared according to the compositions shown in Tables 1 and 2 below, by mixing an abrasive, a nitrogen-containing additive, and a surfactant in a dispersion medium (ultrapure water) while adjusting the pH to the value shown in Table 1 using a pH adjuster.

[0162] The pH of the polishing composition was confirmed with a pH meter (Model: F-73, manufactured by Horiba, Ltd.) (The temperature of the polishing composition during pH measurement was 25°C). In addition, "-" in Table 1 indicates that the component was not added. Each component and number in Table 1 will be explained below.

[0163] Silica A: Colloidal silica with sulfonic acid fixed on the surface [average primary particle size: 35 nm, average secondary particle size: 67 nm, zeta potential: -52 mV (pH = 3-4), -53 mV (pH = 4.5)], Silica B: Colloidal silica with unmodified surface [average primary particle size: 35 nm, average secondary particle size: 67 nm, zeta potential: +3 mV (pH = 3)], PPG: Polypropylene glycol [weight average molecular weight: 400], PG: polyglycerol [weight average molecular weight: 500], HEPES: 4-(2-hydroxyethyl)piperazine-1-ethanesulfonic acid (compound of the formula below),

[0164] [ka]

[0165] BES: N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid (compound of the formula below),

[0166] [ka]

[0167] BICINE: N,N-bis(2-hydroxyethyl)glycine (compound of the formula below),

[0168] [ka]

[0169] HfO2: Hafnium oxide, Poly-Si: Polysilicon, SiGe: Silicon Germanium; TEOS: Silicon oxide produced from tetraethyl orthosilicate (also known as tetraethyl silicate). RR[Å / min]: Polishing rate.

[0170] [Polished wafer] The following four types of wafers were prepared:

[0171] - Wafers (silicon wafers) with a hafnium oxide film layered to a thickness of 400 Å, - Wafers with a 5,000 Å polysilicon film (silicon wafers), - Wafers with a 1,500 Å silicon germanium film (silicon wafers), A wafer (silicon wafer) with a 10,000 Å TEOS film.

[0172] [Polishing conditions] Using the polishing composition obtained in the above-mentioned preparation of polishing composition, each of the above-mentioned wafers was polished under the following conditions.

[0173] Polishing equipment: Ebara Corporation FREX 300S H, Polishing pad: Rohm and Haas IC1010, Dresser: 3M Corp. A188, Hafnium oxide film polishing time: 10 seconds, Polishing time for other films: 60 seconds, Polishing platen pressure: 140hPa (2.03psi), Polishing platen rotation speed: 100 rpm, Supply rate of polishing composition: 300 ml / min. Dresser rotation speed: 90 rpm, Dress pressing force: 22N, Dress time: 15 seconds, Pure water flow rate: 2,000ml / min.

[0174] [Measurement of polishing speed] The film thickness before and after polishing was measured using a spectroscopic ellipsometric film thickness measurement device, and the polishing rate was calculated. Note that 1 Å=0.1 nm.

[0175] Spectroscopic ellipsometric film thickness measurement device: KLA-Tencor ASET-F5X

[0176] [Table 1]

[0177] [Table 2]

[0178] As shown in Tables 1 and 2, the comparison of Examples 1 to 5 with Comparative Example 1, and the comparison of Examples 6 to 14 with Comparative Example 2 reveal that the addition of the nitrogen-containing additive in the embodiment of the present invention contributes to an improvement in the polishing rate of hafnium oxide. In Comparative Examples 4 to 7, nitrogen-containing additives were added, but they were not the nitrogen-containing additives in the embodiment of the present invention, so the polishing rate of hafnium oxide could not be improved compared to Examples 1 to 14. In addition, the type of abrasive is different between Example 6 and Comparative Example 3. In Example 6, the abrasive in the embodiment of the present invention is used, so the polishing rate of hafnium oxide can be improved. In addition, the polishing compositions of Examples 6 to 8 and Comparative Examples 8 and 9 have the same components, but Comparative Examples 8 and 9, in which the pH is outside the pH range in the embodiment of the present invention, could not improve the polishing rate of hafnium oxide.

[0179] Furthermore, as shown in Table 1 and as can be seen from the experimental results of Examples 6 to 14, when polishing is performed using a polishing composition containing a surfactant, the polishing rate of silicon-based materials (polysilicon, silicon germanium, TEOS, etc.) is further reduced, and hafnium oxide is polished at a higher rate than silicon-based materials, thereby more effectively achieving the effect of selectively removing hafnium oxide.

Claims

1. (a) an anionic abrasive; (b) a nitrogen-containing additive; and (c) a dispersion medium; The pH is equal to or greater than 2 and less than 5, The polishing composition according to the (b) nitrogen-containing additive includes at least one selected from the group consisting of the following (i), (ii), and (iii): (i) A compound selected from the group consisting of a guanidine compound represented by the following formula (I), an amidine compound represented by the following formula (II), and a salt thereof: 【Chemistry 1】 【Chemistry 2】 During the ceremony, R １ , R ２ , R ３ , R ４ , R １１ and R １２ each independently represents a hydrogen atom, a cyano group, a nitro group, a nitroso group, an amino group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group, or a -C(=O)-O-alkyl group; R ６ is a hydrogen atom, a cyano group, a nitro group, a nitroso group, an aminoalkyl group, an alkyl group, an alkoxy group, an aryl group, a heterocyclic group, a -C(=O)-alkyl group or a -C(=O)-O-alkyl group, the aryl group or the heterocyclic group may be optionally substituted with one or more groups independently selected from a nitro group, a nitroso group, an amino group, or an alkyl group; R ５ are each independently a hydrogen atom, an alkyl group, or an alkoxy group; (ii) a cyclic amino acid; (iii) Sulfonic acid compounds having an amino group.

2. The R １ , the R ２ and the R ６ and each independently represents a hydrogen atom, an alkyl group, or an alkoxy group.

3. The polishing composition according to claim 1, wherein the nitrogen-containing additive (b) is a guanidine compound represented by formula (I), an amidine compound represented by formula (II), or a salt thereof, and the salt is a carbonate, hydrochloride, sulfate, phosphate, or nitrate.

4. The (b) nitrogen-containing additive is a guanidine compound represented by the formula (I), and the R １ and the R ２ and each independently represents a hydrogen atom, an alkyl group, or an alkoxy group.

5. 2. The polishing composition according to claim 1, wherein the (ii) cyclic amino acid has a structure represented by the following formula (III): 【Chemistry 3】 During the ceremony, R ７ is a hydrogen atom, an alkyl group or an alkoxy group, R ８ Ha-(CH ２ ) ｐ -Q, p is 0, 1 or 2, and Q is an aryl group or a heterocyclic group, which may optionally be substituted with one or more -OH or one or more hydroxyalkyl groups; or R ７ , R ８ and the carbon atom and nitrogen atom attached thereto together form a 5- to 6-membered heterocycle.

6. 2. The polishing composition according to claim 1, wherein the cyclic amino acid (ii) is proline, tryptophan or histidine.

7. 2. The polishing composition according to claim 1, wherein the (iii) sulfonic acid compound having an amino group is a sulfonic acid compound having a primary amide group, a secondary amide group or a tertiary amide group.

8. The polishing composition according to claim 7, wherein the (iii) sulfonic acid compound having an amino group has a structure represented by the following formula (IV): 【Chemistry 4】 During the ceremony, n is 1, 2, 3 or 4; R ９ and R １０ are each independently a hydrogen atom, an amino group, an aminoalkyl group, an alkyl group, or a hydroxyalkyl group; or R ９ and R １０ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocycle, which may be optionally substituted with one or more -OH groups, or one or more hydroxyalkyl groups.

9. 2. The polishing composition according to claim 1, wherein the anionic abrasive (a) is a surface-modified colloidal silica.

10. The polishing composition according to claim 1 , wherein the dispersion medium (c) is water.

11. The polishing composition according to claim 1 , further comprising: (d) a surfactant.

12. The polishing composition according to claim 11, wherein the surfactant (d) is a polyether.

13. The polishing composition according to claim 11, wherein the (d) surfactant is at least one selected from the group consisting of polyethylene glycol, polypropylene glycol, polyglycerol, and copolymers thereof.

14. 2. The polishing composition according to claim 1, wherein the content of the anionic abrasive (a) is 0.1 to 15 mass % based on the total mass of the polishing composition.

15. 2. The polishing composition according to claim 1, wherein the content of the nitrogen-containing additive (b) relative to the total mass of the polishing composition is 0.005 to 5 mass %.

16. A surface treatment method, comprising a step of performing a surface treatment on an object to be treated with the polishing composition according to claim 1.

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