Additives for chemical mechanical polishing and their manufacturing methods, as well as the composition of polishing fluids.

Abstract

The additive is formulated as used in chemimechanical milling and contains a polymer (P). The polymer (P) contains structural units (A) derived from vinyl monomers having a -(LO)nR group, and the amount of structural units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups and salts thereof, totaling 0 to 0.6% by mass, and the dispersion (PDI) of the polymer (P) expressed as weight average molecular weight (Mw) / number average molecular weight (Mn) is 2.0 or less. (However, L is an alkyl group having 4 or fewer carbon atoms, n is any integer from 3 to 150, and R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms).

Description

Technical Field

[0001] This invention relates to additives for chemical mechanical polishing (CMP) and their manufacturing methods, as well as polishing slurry compositions. More specifically, it relates to additives for CMP, which are important in the manufacturing process of semiconductor devices, and their manufacturing methods, as well as polishing slurry compositions. Prior Technology

[0002] Semiconductor devices are used in almost all known electronic devices, such as information and communication equipment and home appliances, becoming indispensable to modern life. In recent years, with the popularization of IoT and the utilization of cloud computing, the functions of semiconductor devices have increased even further. To date, although the integration and scaling of semiconductor chips have been achieved at a remarkable pace, the demand for high performance has never ceased, and the importance of microfabrication technology is increasing. In particular, chemical mechanical polishing (CMP) technology is extremely important for achieving high-precision multilayer wiring formation and is frequently used in various stages of semiconductor device manufacturing, such as insulating film planarization, metal plug formation, and embedded wiring formation. In CMP (Chemical Mechanical Polishing), polishing slurries are used to improve polishing speed and machining accuracy. Polishing slurries typically contain abrasive particles, polishing accelerators, water-soluble polymers, and surfactants. Among these, water-soluble polymers or surfactants are added to the polishing slurry to improve the flatness of the workpiece or suppress surface defects. They adsorb onto the surface of the polishing film, protecting the surface and maintaining its integrity while also suppressing excessive polishing action. However, if the adsorption of the polishing film is too strong, there is a problem of insufficient polishing speed. [Previous Technical Documents] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2000-017195 [Patent Document 2] Japanese Patent Application Publication No. 2007-318072 [Patent Document 3] International Publication No. 2009 / 104334 Summary of the Invention

[0004] [The problem the invention aims to solve]

[0005] Patent Document 1 discloses a polishing slurry composition comprising a copolymer of ammonium acrylate and methyl acrylate, and cerium oxide particles. Using this polishing slurry composition improves the flatness of the polished surface compared to using a polishing slurry without the acrylic copolymer. However, its flatness is not yet sufficient. For example, when the aforementioned polishing slurry composition is used to polish a polishing film with uneven surfaces, in addition to polishing the convex parts, the concave parts are also polished simultaneously, resulting in a dish-like bending phenomenon on the polished surface, especially at points corresponding to the concave parts. This phenomenon is called depression, and there is a problem that the proportion of the total area of ​​the depressions observed when viewing the uneven surface from a plane is relatively large. To suppress the aforementioned depressions and obtain a highly flat polished surface, Patent Document 2 proposes a polishing liquid composition comprising cerium dioxide particles as abrasive grains, and dihydroxyethyl glycine and polyoxyalkylene ethers as additives. Although the proposal suggests that these two compounds adsorb onto the abrasive grains and the polishing film respectively, thereby protecting the depressions in the polishing film and preventing over-polishing to obtain a flat surface, the surfactants, due to their small molecular weight, have weak adsorption on the polishing film, resulting in insufficient protective effect. Patent document 3 proposes a method to reduce indentation in copper, comprising a dry polymer containing anionic functional groups and a graft polymer containing polyolefin diols. Although the proposed method involves the adsorption of the dry anionic functional groups onto the copper surface, resulting in a smooth surface by adjusting the grinding speed, the reduced grinding speed raises the issue of reduced productivity.

[0006] The present invention was made in view of the above-mentioned matters, and its object is to provide an additive for chemical mechanical polishing of the uneven surface of the object being polished, wherein the polishing speed of the protrusion (oxide film) is sufficiently fast and the depression is significantly reduced, as well as the additive manufacturing method thereof, and the polishing fluid composition thereof. [Methods used to solve problems]

[0007] Through diligent research in order to solve the aforementioned problems, the inventors discovered that these problems can be solved by using additives containing polymers with a narrow molecular weight distribution and specific structural units. This invention is based on this discovery. According to this specification, the following means are provided.

[0008] [1] An additive for chemical mechanical polishing, comprising a polymer (P), characterized in that... The aforementioned polymer (P) contains a total of 0 to 0.6% by mass of a building unit (A) derived from a vinyl monomer having a -(LO)nR group, and the content of building units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups and salts thereof. The dispersion (PDI) of the aforementioned polymer (P), expressed as weight average molecular weight (Mw) / number average molecular weight (Mn), is 2.0 or less. (However, L is an alkyl group with 4 or fewer carbon atoms, n is any integer from 3 to 150, and R is a hydrogen atom or a alkyl group with 1 to 4 carbon atoms in a monovalent state). [2] The additives described in [1] above, wherein the number average molecular weight (Mn) of the aforementioned polymer (P) is 1,000 to 100,000. [3] As described in [1] or [2] above, wherein the polymer (P) further contains a building unit (B) derived from at least one monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomers having -(LO)nR groups). [4] As described in [3] above, the aforementioned building unit (B) is a building unit derived from (meth)acrylate and / or (meth)acrylate amine type monomers. [5] As described in [3] or [4] above, the aforementioned building unit (B) is a building unit derived from a monomer with an SP value of 17 to 25 (J / cm 3) 0.5 calculated by Fedors' estimation method. [6] The additive described in any of [1] to [5] above, wherein the polymer (P) is a block polymer. [7] The additive described in any of [1] to [6] above, wherein the polymer (P) contains polymer block A and polymer block B, The aforementioned polymer block A has the aforementioned building block (A). The aforementioned polymer block B has the aforementioned building block (B). [8] As described in [7] above, the ratio (A / B) of the polymer (P) to the polymer block A and the polymer block B is 50 / 50 to 99.9 / 0.1 by mass. [9] An abrasive composition for use in chemical mechanical polishing for planarization of the surface of at least one of an insulating layer and a wiring layer, comprising the additives described in any one of [1] to [8] above, and cerium oxide and / or silicon dioxide.

[10] A manufacturing method, which is a method for manufacturing an additive for chemical mechanical polishing slurry comprising a polymer, characterized in that... The aforementioned polymer contains building units derived from vinyl monomers having -(LO)nR groups, and the content of building units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups, and salts thereof, totaling 0 to 0.6% by mass, and has a step of manufacturing the polymer by living radical polymerization, wherein the polymer has a dispersion (PDI) of less than 2.0 expressed as the weight average molecular weight (Mw) / number average molecular weight (Mn) of the aforementioned polymer. (However, L is an alkyl group with 4 or fewer carbon atoms, n is any integer from 3 to 150, and R is a hydrogen atom or a alkyl group with 1 to 4 carbon atoms in a monovalent state). [Invention Effects]

[0009] According to the present invention, an additive for chemical mechanical polishing can be provided that allows for sufficiently rapid polishing of the protrusions (oxide film) on the uneven surface of the object being polished, and can significantly reduce depressions. Furthermore, a polishing slurry composition containing the aforementioned additive and cerium oxide and / or silicon dioxide can be provided. Moreover, a method for manufacturing an additive for chemical mechanical polishing slurries comprising a polymer can be provided. Implementation

[0010] The present invention will now be described in detail. In this specification, "(meth)acrylonitrile" refers to acrylonitrile and / or methacrylonitrile, and "(meth)acrylate" refers to acrylate and / or methacrylate. Furthermore, "(meth)acrylonitrile" refers to acrylonitrile and / or methacrylonitrile.

[0011] According to the present invention, an additive for chemical mechanical polishing is provided that allows for sufficiently rapid polishing of the protrusions (oxide film) on the uneven surface of the object being polished, and can significantly reduce depressions; and a polishing slurry composition containing the aforementioned additive and cerium oxide and / or silicon dioxide is provided. Furthermore, a method for manufacturing an additive for chemical mechanical polishing slurries comprising a polymer is provided. The present invention will now provide a detailed description of the additives for chemical mechanical polishing, the composition of polishing fluids, and the manufacturing method of the additives for chemical mechanical polishing fluids containing polymers.

[0012] Additives for chemical mechanical grinding The additive for chemical mechanical grinding provided by the present invention contains a polymer (P). The aforementioned polymer (P) contains a total of 0 to 0.6% by mass of a building unit (A) derived from a vinyl monomer having a -(LO)nR group, and the content of building units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups and salts thereof. The dispersion (PDI) of the aforementioned polymer (P), expressed as weight average molecular weight (Mw) / number average molecular weight (Mn), is 2.0 or less.

[0013] <Polymer (P)> The polymer (P) used in this invention contains building units derived from vinyl monomers having a -(LO)nR group. Examples of L in the aforementioned polymer (P) include methylene, ethyl, -CHMe-, n-propyl, -CHEt-, etc. -CHMeCH 2-yl, -CH 2CHMe-yl, n-extrinyl, -CH(n-Pr)-yl, -CH(i-Pr)-yl, -CHEtCH 2-yl, -CH 2CHEt-yl, -CHMeCH2CH2-yl, -CH2CHMeCH2-yl, -CH2CH2CHMe-yl, etc. The L group in the aforementioned polymer (P) can be all the same. Furthermore, the L group in the aforementioned polymer (P) can contain two or more different groups. Considering the ease of obtaining industrial raw materials and the water solubility of the aforementioned polymer (P), the L group in the aforementioned polymer (P) is preferably any one of ethyl, -CHMeCH2-yl, or -CH2CHMe-yl, with ethyl being more suitable.

[0014] In the aforementioned polymer (P), n is any integer from 3 to 150. When the -(LO)nR group contained in the aforementioned polymer (P) participates in reducing the depression by adsorbing and protecting the oxide film or by exhibiting high responsiveness to changes in grinding pressure, the upper limit of n is preferably 100 or less, more preferably 50 or less, even more preferably 30 or less, and even more preferably 15 or less. The lower limit of n is preferably 4 or more, more preferably 5 or more, even more preferably 6 or more, and even more preferably 7 or more. The preferred range of n can be arbitrarily combined with the numerical values ​​exemplified by the aforementioned upper and lower limits. For example, the preferred range of n can be 4 or more and 100 or less, or 5 or more and 50 or less, or 6 or more and 30 or less, or 7 or more and 15 or less. Furthermore, when L is constructed using only one base, n is any integer within the aforementioned range. On the other hand, when L is constructed using two bases, The -(LO)nR basis can be represented using the -(L 1O)n 1-(L 2O)n 2-R basis. In this case, the sum of n 1 and n 2 becomes any integer contained within the aforementioned range. The same consideration can be given to the case where L is constructed using three or more bases.

[0015] In the aforementioned polymer (P), R is a hydrogen atom or a hydrocarbon group with 1 to 4 carbon atoms and a monovalent valence. Examples of hydrocarbon groups with 1 to 4 carbon atoms and a monovalent valence include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, tert-butyl, etc. Considering the availability of industrial raw materials and the water solubility of the aforementioned polymer (P), it is preferable that R in the aforementioned polymer (P) is a hydrogen atom or a methyl group, and methyl is more suitable.

[0016] Anionic (co)polymers are typically adsorbed onto the surface of a positively charged nitride film. This improves the abrasion selectivity with the oxide film on the protrusions, resulting in a flat surface. However, with the nitride film exposed, the abrasion rate of the oxide film increases near the end of the abrasion process, leading to indentations. Furthermore, with anionic additives, pH changes can alter the stability of the abrasive solution composition, causing abrasion damage due to coarsening of the abrasive particles. Considering these factors, the total content of building units derived from monomers containing one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups, and their salts, relative to the entire polymer (P), is preferably 0 to 0.6% by mass. The content of building units derived from monomers containing one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups and their salts, relative to the entirety of the aforementioned polymer (P), is preferably 0 to 0.5% by mass, more preferably 0 to 0.4% by mass, even more preferably 0 to 0.3% by mass, and even more preferably 0 to 0.2% by mass.

[0017] The dispersion index (PDI) of the aforementioned polymer (P), expressed as weight average molecular weight (Mw) / number average molecular weight (Mn), is 2.0 or less. In polymers with abrasive particle dispersibility, molecular weight is considered to affect the adsorption / desorption rate of the abrasive material; therefore, it is generally believed that the smaller the molecular weight of the polymer, the higher the adsorption / desorption rate of the abrasive material. Furthermore, polymers with larger molecular weights are considered to easily form agglomerated structures of abrasive particles due to shear force. Therefore, polymers with abrasive particle dispersibility are preferably those with a narrow molecular weight distribution. From this perspective, the PDI of the aforementioned polymer (P) is preferably 1.8 or less, more preferably 1.5 or less, even more preferably 1.3 or less, and even more preferably 1.2 or less. The lower limit of the PDI is typically 1.0. Also, in this specification, the number average molecular weight (Mn) and weight average molecular weight (Mw) of the polymer are values ​​converted from polystyrene determined by gel permeation chromatography (GPC). Details of the molecular weight determination are described in the section on examples.

[0018] The number average molecular weight (Mn) of the aforementioned polymer (P) is preferably 1,000 to 100,000. When Mn is 1,000 or higher, the wettability of the surface of the object being ground can be sufficiently ensured, and the reduction in grinding speed can be suppressed. Furthermore, when Mn is 100,000 or lower, the agglomeration of abrasive particles by shear force can be sufficiently suppressed, and defects such as scratches during grinding can be sufficiently suppressed. From this point of view, the Mn of the aforementioned polymer (P) is preferably 1,500 or higher, more preferably 2,000 or higher, and even more preferably 2,500 or higher. The upper limit of the Mn of the aforementioned polymer (P) is preferably 60,000, even more preferably 30,000, even more preferably 10,000, and even more preferably 6,000. The preferred range of number average molecular weight can be expressed by any combination of the values ​​exemplified by the upper and lower limits mentioned above. For example, the preferred range of the aforementioned polymer (P) may be 1,500 to 60,000, or 2,000 to 30,000, or 2,500 to 10,000.

[0019] Although the details of the manufacturing method of the aforementioned polymer (P) are described later, the aforementioned polymer (P) can be manufactured, for example, by polymerizing a monomeric component containing the aforementioned vinyl monomer having a -(LO)nR group. The vinyl monomer having a -(LO)nR group is not particularly limited to a compound that combines a polymerizable vinyl group and a -(LO)nR group. Examples of compounds containing polymerizable vinyl groups include esters or amide-type compounds of unsaturated acids such as (meth)acrylic acid, crotonic acid, maleic acid, and itaconic acid, aromatic vinyl compounds, and vinyl ether compounds.

[0020] Specific examples of the vinyl monomers having the -(LO)nR group that can be used in this invention include N-[2-[2-(2-methoxyethoxy)ethoxy]ethyl](meth)acrylamide, 1-[(meth)acrylamide]-3,6,9,12,15,18,21-heptaoxadocosane, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, polytetramethyl glycol mono(meth)acrylate, poly(ethylene glycol-propylene glycol) mono(meth)acrylate, poly(ethylene glycol-tetramethyl glycol) mono(meth)acrylate, and poly(ethylene glycol-propylene glycol-tetramethyl glycol) mono((ethylene glycol-propylene glycol-tetramethyl glycol) mono(( Methacrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene tetramethyl glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monomethoxy polyethylene glycol mono(meth)acrylates, monoethoxy polyethylene glycol mono(meth)acrylates, mono-n-propoxy polyethylene glycol mono(meth)acrylates, mono-i-propoxy polyethylene glycol mono(meth)acrylates, mono-n-butoxy polyethylene glycol mono(meth)acrylates, mono-t-butoxy polyethylene glycol mono(meth)acrylates, etc. Among these, polyethylene glycol mono(meth)acrylate and monomethoxy polyethylene glycol mono(meth)acrylate are preferred, more preferably polyethylene glycol monoacrylate and monomethoxy polyethylene glycol monoacrylate, and even more suitable is monomethoxy polyethylene glycol monoacrylate. Examples of commercially available products under the name "Shang" include the BLEMMER AE series, AME series, AP series, PE series, PME series, PP series, and 50PEP series manufactured by Nippon Oil Co., Ltd.; the AM series manufactured by Shin-Nakamura Chemical Industry Co., Ltd.; and LIGHT ACRYLATE MTG-A and LIGHT ACRYLATE 130A manufactured by Kyoeisha Chemical Co., Ltd. "BLEMMER" is a registered trademark of Nippon Oil Co., Ltd., and "LIGHT ACRYLATE" is a registered trademark of Kyoeisha Chemical Co., Ltd.

[0021] Relative to the aforementioned polymer (P) as a whole, derived from the aforementioned having The content of the building unit (A) of the vinyl monomer of the -(LO)nR group is preferably 50% by mass or more. More preferably, the content of the aforementioned building unit (A) is 80% by mass or more, even more preferably 85% by mass or more, even more preferably 90% by mass or more, and even more preferably 93% by mass or more. Furthermore, the upper limit of the aforementioned building unit (A) is 100% by mass, preferably 99% by mass, even more preferably 98% by mass, even more preferably 97% by mass, and even more preferably 96% by mass. The preferred range of the aforementioned building unit (A) content can be expressed by any combination of the values ​​exemplified by the upper and lower limits above. For example, the preferred range of the building unit (A) content can be 50% by mass or more and 100% by mass, or 80% by mass or more and 99% by mass, or 85% by mass or more and 98% by mass, or 90% by mass or more and 97% by mass, or 93% by mass or more and 96% by mass. When the content of the building units derived from the aforementioned vinyl monomers with -(LO)nR groups is within the above range, there is a high responsiveness to changes in grinding pressure. In the case of a protruding oxide film (high grinding pressure), no adsorption occurs. Although the grinding speed is not reduced, grinding proceeds and the nitride film is exposed. In the case of a concave grinding object (low grinding pressure), adsorption occurs at the oxide film interface, suppressing the tendency for excessive grinding. Through these effects, without reducing the grinding speed, it is easier to obtain a well-polished surface with reduced pitting.

[0022] The aforementioned polymer (P) can be a single polymer of the aforementioned vinyl monomer having a -(LO)nR group, or it can be a polymer using multiple types of the aforementioned vinyl monomer having a -(LO)nR group. Furthermore, the aforementioned polymer (P) is preferably a copolymer of at least one monomer selected from the group consisting of the aforementioned vinyl monomer having a -(LO)nR group, vinyl monomers containing amide groups, and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomer having a -(LO)nR group). By using a monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups, the hydrophilicity / hydrophobicity balance of the aforementioned polymer (P) can be adjusted as desired, allowing the aforementioned polymer (P) to be appropriately adsorbed at the oxide film interface and suppressing excessive grinding.

[0023] Examples of vinyl monomers containing an amide group include (meth)acrylamide, tert-butyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, (meth)acrylamide (Acryloyl)morpholine and other (meth)acrylamide derivatives, N-vinylacetamide, N-vinylmethylamine, N-vinylisobutylacetamide and other N-vinylamide monomers, and one or more of these monomers may be used. Among these, preferred are (meth)acrylamide, tert-butyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, and (meth)acrylylmorpholine, etc., which are (meth)acrylamide derivatives. Furthermore, monomers with an SP value of 17-25 (J / cm³) 0.5 calculated using Fedors' estimation method (refer to the 1974 issue of Polymer Engineering & Science, Volume 14, No. 2, pp. 147-154, etc.), and even more preferably monomers with an SP value of 18-21.8 (J / cm³) 0.5, are preferred. Specifically, it is particularly suitable for tert-butylacrylamide and N-isopropylacrylamide.

[0024] Examples of vinyl monomers containing ester groups include vinyl esters such as vinyl acetate and vinyl propionate; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, and ethylhexyl methacrylate. And alkyl esters of (meth)acrylate such as n-decyl (meth)acrylate; aliphatic cyclic esters of (meth)acrylate such as cyclohexyl (meth)acrylate, methylcyclohexyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, cyclododecyl (meth)acrylate, isobornyl (meth)acrylate, adamantane (meth)acrylate, dicyclopentenyl (meth)acrylate, and dicyclopentane (meth)acrylate; phenyl methacrylate, benzyl (meth)acrylate, phenoxymethyl (meth)acrylate, Aromatic esters of (meth)acrylic acid, such as 2-phenoxyethyl methacrylate and 3-phenoxypropyl methacrylate; hydroxyalkyl esters of (meth)acrylic acid, such as 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate and 4-hydroxybutyl methacrylate; N-[2-(methylamino)ethyl](meth)acrylate, N-[2-(dimethylamino)ethyl](meth)acrylate, N-[2-(ethylamino)ethyl](meth)acrylate and N-[2-(diethylamino)ethyl](meth)acrylate. (ii)alkylaminoalkyl(meth)acrylates such as [methylamino]ethyl[meth]acrylate; epoxy-containing (meth)acrylates such as glycidyl methacrylate, 4-hydroxybutyl(meth)acrylate glycidyl ether and 3,4-epoxycyclohexylmeth(meth)acrylate; alkoxyalkyl(meth)acrylates such as 2-methoxyethyl(meth)acrylate, 2-(2-methoxyethoxy)ethyl(meth)acrylate, methoxydipropylene glycol(meth)acrylate, etc. Among these, monomers with an SP value of 17-25 (J / cm³) 0.5 calculated using the aforementioned Fedors estimation method are preferred, and monomers with an SP value of 18-21.8 (J / cm³) 0.5 are even more preferred. Specifically, methyl acrylate, ethyl acrylate, n-propyl acrylate, and n-butyl acrylate are particularly suitable.

[0025] The aforementioned polymer (P) may further have a structural unit (B) derived from at least one monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomers having -(LO)nR groups). The content of the aforementioned structural unit (B) relative to the entire aforementioned polymer (P), that is, the total content of structural units derived from the aforementioned vinyl monomers containing amide groups (excluding the aforementioned vinyl monomers having -(LO)nR groups) and the content of structural units derived from the aforementioned vinyl monomers containing ester groups (excluding the aforementioned vinyl monomers having -(LO)nR groups), is 0% by mass or more. The content of the aforementioned structural unit (B) is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, and even more preferably 4% by mass or more. Furthermore, the upper limit of the content of the aforementioned structural unit (B) is preferably 50% by mass, more preferably 20% by mass, even more preferably 15% by mass, and even more preferably 10% by mass. The preferred range of the content of the aforementioned building block (B) can be expressed by any combination of the lower and upper limits mentioned above. For example, the preferred range of the content of the aforementioned building block (B) can be 1% to 50% by mass, or 2% to 20% by mass, or 3% to 15% by mass, or 4% to 10% by mass.

[0026] When the total content of the building units derived from the vinyl monomers containing amide groups and the building units derived from the vinyl monomers containing ester groups, relative to the entire polymer (P), is included within the above range, it is easy to obtain a good polished surface with reduced pitting.

[0027] The aforementioned polymer (P) may include other copolymerizable monomers as building units, in addition to at least one monomer selected from the group consisting of vinyl monomers having -(LO)nR groups, vinyl monomers containing amide groups, and vinyl monomers containing ester groups. Specific examples of other copolymerizable monomers include alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, t-butyl vinyl ether, n-hexyl vinyl ether, 2-ethylhexyl vinyl ether, n-octyl vinyl ether, n-nonyl vinyl ether, and n-decyl vinyl ether; vinyl alcohols such as vinyl alcohol, 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, and 4-hydroxybutyl vinyl ether; aromatic vinyl compounds such as styrene, vinyltoluene, and vinylxylene; and α-olefins such as ethylene, propylene, and butene. One or more of these monomers can be combined as other copolymerizable monomers. The content of building units derived from the aforementioned other copolymerizable monomers relative to the entire polymer (P) is preferably 10% by mass or less. The content of building units derived from the aforementioned other monomers is more preferably 8% by mass or less, even more preferably 5% by mass or less, even more preferably 3% by mass or less, and even more preferably 1% by mass or less.

[0028] When the aforementioned polymer (P) is a copolymer containing the aforementioned vinyl monomer having a -(LO)nR group, its molecular structure is preferably a block copolymer.

[0029] In the block copolymer, the polymer (P) is preferably a block copolymer comprising a polymer block A having a structural unit (A) derived from the aforementioned vinyl monomer having a -(LO)nR group, and a polymer block B having a structural unit (B) derived from a monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomers having a -(LO)nR group). Previously, water-soluble polymers used as additives in chemical mechanical polishing (CMP) have included both single polymers and random copolymers. However, polymers with functional groups adsorbed on the substrate surface and distributed throughout the polymer structure lack concentrated adsorption sites, resulting in weak surface protection of the workpiece and over-polishing under high polishing pressure. On the other hand, block copolymers are considered to have a structure where functional groups are concentrated on the substrate surface, allowing for sufficient adsorption and preventing over-polishing of the workpiece.

[0030] Block copolymers The block copolymer suitable for use in this invention is a block copolymer comprising polymer block A and polymer block B. Polymer Block A Polymer block A has a building unit (A) derived from the aforementioned vinyl monomer having a -(LO)nR group. The aforementioned polymer block A can be a single polymer of the aforementioned vinyl monomer having a -(LO)nR group, or a polymer using multiple types of the aforementioned vinyl monomer having a -(LO)nR group. Furthermore, without impairing the effects of the invention, the aforementioned polymer block A can also be a copolymer of at least one monomer selected from the group consisting of the aforementioned vinyl monomer having a -(LO)nR group, vinyl monomers containing amide groups, and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomer having a -(LO)nR group), and / or other copolymerizable monomers.

[0031] Relative to the entirety of the aforementioned polymer block A, the content of the structural unit (A) derived from the aforementioned vinyl monomer having the -(LO)nR group is preferably 80% by mass or more, more preferably 90% by mass or more. Furthermore, the content of the aforementioned structural unit (A) may be 95% by mass or more, or 97% by mass or more, or 99% by mass or more. Moreover, the maximum content of the aforementioned structural unit (A) is 100% by mass. When the content of the building unit (A) derived from the aforementioned vinyl monomer with the -(LO)nR group is within the above range, it has a high responsiveness to changes in grinding pressure. In the case of a protruding oxide film (high grinding pressure), it does not adsorb. Although the grinding speed is not reduced, grinding is carried out and the nitride film is exposed. In the case of a concave grinding object (low grinding pressure), it adsorbs at the oxide film interface and suppresses the tendency of excessive grinding. Through these effects, without reducing the grinding speed, it is easier to obtain a well-polished surface with reduced pitting.

[0032] The weight-average molecular weight of the aforementioned polymer block A is preferably 500 or more, more preferably 900 or more, even more preferably 1,500 or more, even more preferably 2,100 or more, and even more preferably 2,700 or more. The upper limit of the weight-average molecular weight of the aforementioned polymer block A is preferably 100,000, more preferably 60,000, even more preferably 30,000, even more preferably 10,000, and even more preferably 6,000. The preferred range of the weight-average molecular weight of the aforementioned polymer block A can be expressed by any combination of these lower and upper limits. For example, the preferred range of the weight average molecular weight of the aforementioned polymer block A may be 500 or more and 100,000 or less, or 900 or more and 60,000 or less, or 1,500 or more and 30,000 or less, or 2,100 or more and 10,000 or less, or 2,700 or more and 6,000 or less. When the weight-average molecular weight of the aforementioned polymer block A is within the range described above, it is preferable to ensure sufficient wettability of the surface of the object being ground and to suppress the decrease in grinding speed. Furthermore, it is preferable to effectively suppress the agglomeration of abrasive particles caused by shear force and to effectively suppress defects such as scratches that occur during grinding.

[0033] Polymer Block B Polymer block B has a structural unit (B) derived from at least one monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding vinyl monomers having -(LO)nR groups). The polymer block B may be a single polymer of a monomer selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding vinyl monomers having -(LO)nR groups), or a polymer using two or more monomers selected from the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding vinyl monomers having -(LO)nR groups). Furthermore, provided that the effects of the present invention are not impaired, the aforementioned polymer block B may be a monomer selected from at least one of the group consisting of vinyl monomers containing amide groups and vinyl monomers containing ester groups (excluding the aforementioned vinyl monomers having -(LO)nR groups), a copolymer of the aforementioned vinyl monomers having -(LO)nR groups, and / or the aforementioned other copolymerizable monomers.

[0034] The content of the aforementioned structural unit (B), relative to the entirety of the aforementioned polymer block B, is preferably 80% by mass or more, more preferably 90% by mass or more. Furthermore, the total content of the aforementioned structural unit (B) can also be 95% by mass or more, 97% by mass or more, or 99% by mass or more. The upper limit of the total content of the aforementioned structural unit (B) is 100 by mass.

[0035] The weight-average molecular weight of the aforementioned polymer block B is preferably 100 or more, more preferably 120 or more, even more preferably 130 or more, even more preferably 140 or more, and even more preferably 150 or more. The upper limit of the weight-average molecular weight of the aforementioned polymer block B is preferably 50,000, more preferably 10,000, even more preferably 5,000, even more preferably 1,000, and even more preferably 500. The preferred range of the weight-average molecular weight of the aforementioned polymer block B can be expressed by any combination of the aforementioned lower and upper limits. For example, the preferred range of the weight-average molecular weight of the aforementioned polymer block B can be 100 or more and less than 50,000, or 120 or more and less than 10,000, or 130 or more and less than 5,000, or 140 or more and less than 1,000, or 150 or more and less than 500.

[0036] Block copolymers suitable for use in this invention may be those having one or more of the aforementioned polymer blocks A and B. Examples of such block copolymers include, for instance, an AB diblock copolymer composed of polymer blocks A and B, an ABA triblock copolymer composed of polymer blocks A / B / A, and a BAB triblock copolymer. Furthermore, the aforementioned block copolymers may be multiblock copolymers having four or more polymer blocks, or block copolymers with a structure such as ABC or ABCA containing polymer blocks C other than polymer blocks A and B. Compared to structures like ABC, the aforementioned block copolymers require fewer manufacturing steps, thus reducing the possibility of impurities being introduced. From the viewpoint of manufacturing high-purity products, an AB structure is preferred.

[0037] The mass ratio (A / B) of the aforementioned polymer block A to the aforementioned polymer block B in the block copolymer is preferably 50 / 50 to 99.9 / 0.1, more preferably 80 / 20 to 99 / 1, and even more preferably 90 / 10 to 98 / 2. Furthermore, the mass ratio (A / B) of the aforementioned polymer block A to the aforementioned polymer block B in the block copolymer can also be 93 / 7 to 97 / 3. If the mass ratio is within this range, there is a tendency for adsorption onto the oxide film, indicating a protective effect. Furthermore, there is a high responsiveness to changes in grinding pressure. Even when the oxide film has protrusions (high grinding pressure), adsorption does not occur. Even when grinding does not reduce the grinding speed, but grinding continues, exposing the nitride film, and the object being ground becomes concave (low grinding pressure), adsorption occurs at the oxide film interface, suppressing the tendency for over-grinding. It is believed that through these effects, a well-polished surface with reduced depressions can be easily obtained without reducing the grinding speed.

[0038] Furthermore, when the aforementioned block copolymer includes polymer block C other than polymer block A and polymer block B, the total mass ratio of polymer block A and polymer block B relative to the entire block copolymer is preferably 90% by mass or more, more preferably 95% by mass or more. Also, the total mass ratio of polymer block A and polymer block B relative to the entire block copolymer may also be 98% by mass or more, or 99% by mass or more.

[0039] The chemical mechanical polishing additive provided by this invention is a chemical mechanical polishing additive containing a polymer (P). The aforementioned polymer (P) contains a total of 0 to 0.6% by mass of building units (A) derived from vinyl monomers having a -(LO)nR group, and the content of building units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups, and salts thereof. The additive with a dispersion (PDI) of 2.0 or less, expressed as the weight average molecular weight (Mw) / number average molecular weight (Mn) of the aforementioned polymer (P), is acceptable. Accordingly, the chemical mechanical polishing additive provided by the present invention can be in the form of a single component containing only the aforementioned polymer (P), or it can be in the form of containing components different from the aforementioned polymer (P) (hereinafter also referred to as "other components") together with the aforementioned polymer (P).

[0040] The chemical mechanical grinding additive provided by this invention may also include a solvent as another component. Examples of solvents include water, organic solvents, and mixtures of water and organic solvents. Among these, a solvent capable of dissolving the aforementioned polymer (P) is preferred, water or a mixture of water and an organic solvent soluble in water is more preferred, and water is especially preferred. Examples of organic solvents used with water include alcohols such as methanol, ethanol, propanol, and butanol; ketones such as acetone and methyl ethyl ketone; alkyl glycols such as ethylene glycol and propylene glycol; ethers such as ethylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol dimethyl ether, and tetrahydrofuran; esters such as ethylene glycol monomethyl ether acetate and ethyl acetate; acetamide solvents such as N,N-dimethylformamide and N,N-dimethylacetamide; and nitrile solvents such as acetonitrile. As an organic solvent, it can be used alone or in combination with two or more other solvents.

[0041] When the chemical mechanical polishing additive provided by the present invention contains the aforementioned polymer (P) and solvent, from the viewpoint of ensuring sufficient contact between the surface of the object being polished and the surface of the polishing pad and the aforementioned polymer (P), the content of the aforementioned polymer (P) relative to the total mass of the aforementioned polymer (P) and solvent is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. Furthermore, from the viewpoint of suppressing reduced operability by excessively increasing viscosity, the upper limit of the aforementioned polymer (P) content relative to the total mass of the aforementioned polymer (P) and solvent is preferably 70% by mass, more preferably 60% by mass, and even more preferably 50% by mass. The preferred range of the aforementioned polymer (P) content can be expressed by any combination of these lower and upper limits. For example, the preferred range of the aforementioned polymer (P) content relative to the total mass of the aforementioned polymer (P) and solvent may also be 1% by mass or more and 70% by mass or less, 5% by mass or more and 60% by mass or less, or 10% by mass or more and 50% by mass or less.

[0042] <Method for Manufacturing Polymers for Grinding Fluid Additives> The polymer used as a grinding fluid additive can be any polymer (P) that is suitable for use in this invention and is not particularly limited thereto, as long as it does not impair the effects of this invention. For example, the aforementioned polymer (P) can be manufactured by polymerizing the aforementioned monomers using known free radical polymerization methods such as solution polymerization and bulk polymerization. In solution polymerization, for example, the desired polymer can be obtained by placing the solvent and monomer into a reactor, adding a polymerization initiator, and heating the polymerization process.

[0043] Alternatively, a vinyl polymer, such as poly(meth)acrylic acid or a polymer containing anhydride structures or epoxy groups, possessing functional groups that are reactive with alcohols or amines, can be first manufactured using known methods. Then, the aforementioned polymer (P) can be manufactured by subjecting an alcohol having a -(LO)nR group and / or an amine compound having a -(LO)nR group to an esterification, acetylation, etherification, or amination reaction under known conditions in the presence of an acidic catalyst, a basic catalyst, or a dehydrating condensing agent. Furthermore, to adjust the content of acidic functional groups, a known capping reaction, such as a methyl esterification reaction, can be performed.

[0044] Purification can be performed by using known polymer purification methods such as the method described above for manufacturing the aforementioned polymer (P) for use in reprecipitation or porous materials, such that the dispersion (PDI) expressed as weight average molecular weight (Mw) / number average molecular weight (Mn) is 2.0 or less.

[0045] Suitable manufacturing methods for the aforementioned polymer (P) include various controlled polymerization methods such as living radical polymerization and living anionic polymerization. Among these, living radical polymerization is preferred due to its high controllability of molecular weight dispersion (PDI), excellent particle dispersion stability, ease of operation, and applicability to a wide range of monomers. When using living radical polymerization, the polymerization form is not particularly limited; polymerization can be carried out in various forms such as bulk polymerization, solution polymerization, emulsion polymerization, microemulsion polymerization, and suspension polymerization.

[0046] For example, when using living radical polymerization to manufacture the aforementioned polymer (P) through solution polymerization, the solvent and monomer can be placed in a reactor, and a free radical polymerization initiator can be added. Heating is preferred to carry out polymerization and obtain the desired polymer (P). During polymerization, any process such as batch polymerization, semi-batch polymerization, dry continuous polymerization, or continuous stirred tank polymerization (CSTR) can be used.

[0047] When manufacturing the aforementioned polymer (P), a living radical polymerization method utilizing a known polymerization mechanism can be employed. Specific examples of living radical polymerization methods include living radical polymerization using an exchange chain mechanism, living radical polymerization using a bond-dissociation mechanism, and living radical polymerization using an atom-moving mechanism. Specific examples of these include, for living radical polymerization using an exchange chain mechanism, reversible addition-splitting chain transfer polymerization (RAFT), iodine moving polymerization, polymerization using organotellurium compounds (TERP), polymerization using organoantimony compounds (SBRP), and polymerization using organobismuth compounds (BIRP); for living radical polymerization using a bond-dissociation mechanism, the nitrooxygen radical polymerization (NMP); and for living radical polymerization using an atom-moving mechanism, the atom-moving radical polymerization (ATRP). Among these methods, the living radical polymerization method using an exchange chain structure is preferred due to its applicability to the widest range of vinyl monomers and its excellent controllability of polymerization. Furthermore, the RAFT or NMP method is preferred because it avoids contamination of the abrasive material due to the incorporation of metal or semi-metal compounds. Moreover, the RAFT method is particularly preferred from the perspective of its ease of synthesis in aqueous systems where high temperatures are unnecessary.

[0048] In the RAFT process, polymerization occurs through a reversible chain transfer reaction in the presence of a polymerization control agent (RAFT agent) and a free radical polymerization initiator. Various known RAFT agents, such as dithioester compounds, xanthate compounds, trithiocarbonate compounds, and dithiocarbamate compounds, can be used as RAFT agents. Among these, trithiocarbonate compounds and dithiocarbamate compounds are preferred in terms of yielding polymers with smaller molecular weight dispersion. Furthermore, monofunctional compounds with only one active site or polyfunctional compounds with two or more active sites can be used as RAFT agents. The amount of RAFT agent used is appropriately adjusted according to the monomer and the type of RAFT agent used.

[0049] As a free radical polymerization initiator used in RAFT polymerization, known free radical polymerization initiators such as azo compounds, organic peroxides, and persulfates can be used. Among these, azo compounds are preferred due to their ease of operation and low likelihood of causing side reactions during free radical polymerization. Specific examples of azo compounds include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylpentanonitrile), 4,4'-azobis(4-cyanopentanoic acid), 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile), dimethyl-2,2'-azobis(2-methylpropionate), 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis[N-(2-propenyl)-2-methylpropionic acid], and 2,2'-azobis(N-butyl-2-methylpropionic acid). These free radical polymerization initiators can be used in combination with only one type or in combination with two or more types.

[0050] While there is no particular limitation on the amount of free radical polymerization initiator used, from the perspective of obtaining polymers with smaller molecular weight dispersion, it is preferable to set it to 0.5 mol or less, and more preferably 0.2 mol or less, relative to 1 mol of RAFT agent. Furthermore, from the viewpoint of ensuring stable polymerization, the lower limit of the amount of free radical polymerization initiator used is preferably 0.01 mol, and more preferably 0.05 mol, relative to 1 mol of RAFT agent. The amount of free radical polymerization initiator used relative to 1 mol of RAFT agent is preferably 0.01 to 0.5 mol, and more preferably 0.05 to 0.2 mol.

[0051] When using solvents in living radical polymerization, examples of polymerization solvents include aromatic compounds such as benzene, toluene, xylene, and anisole; ester compounds such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate; ketone compounds such as acetone and methyl ethyl ketone; and solvents such as dimethylformamide, acetonitrile, dimethyl sulfoxide, alcohols, and water. These polymerization solvents can be used alone or in combination of two or more.

[0052] In the RAFT polymerization reaction, the reaction temperature is preferably 40°C to 100°C, more preferably 45°C to 90°C, and even more preferably 50°C to 80°C. A reaction temperature above 40°C is preferable for smooth polymerization, while a reaction temperature below 100°C is preferable for suppressing side reactions and mitigating limitations regarding the initiators or solvents that can be used. Furthermore, while the reaction time can be appropriately set depending on the monomers used, it is preferably 1 hour to 48 hours, more preferably 3 hours to 24 hours. Polymerization can also be carried out in the presence of chain transfer agents (e.g., alkyl thiols with 2 to 20 carbon atoms), if necessary. In the manufacturing process, especially when using monomers with acidic groups, there are concerns about metal mixing due to reactor corrosion, etc. Therefore, it is preferable to use equipment with a surface coated with a fluoropolymer resin. Furthermore, in this case, containers for storing products are preferably made of corrosion-resistant resin. When using resin containers, they are preferably made of a material that inhibits the mixing of metals due to the dissolution of fillers, etc.

[0053] ≪Grinding fluid composition≫ The polishing fluid composition provided by the present invention contains at least the aforementioned polymer (P) and abrasive particles. As abrasive particles, at least one particle selected from the group consisting of known inorganic particles, organic particles, and organic-inorganic composite particles can be used.

[0054] Specific examples of inorganic particles include cerium oxide (cerium dioxide), fumed silica, fumed alumina, fumed titanium dioxide, and colloidal silica. Specific examples of organic particles include (meth)acrylic copolymers such as polymethyl methacrylate, polystyrene and polystyrene copolymers, polyacetal, polyamide, polycarbonate, polyolefins and polyolefin copolymers, and phenoxy resins. Organic-inorganic composite particles are those that are chemically bonded to the functional groups of organic and inorganic components without decomposition when used as components of a polishing slurry. Among these, cerium oxide and / or silicon dioxide are preferred due to their lower hardness, which helps suppress defects on the polished surface. In particular, cerium oxide is more suitable than silicon dioxide or alumina because it allows for high-speed polishing of the surface.

[0055] While the average particle size of the aforementioned abrasive grains is not specifically limited, it is generally between 1 nm and 500 nm. From the viewpoint of ensuring high grinding speed, the average particle size of the aforementioned abrasive grains is preferably 2 nm or more, and more preferably 3 nm or more. From the viewpoint of suppressing the occurrence of scratches on the surface of the object being ground, the upper limit of the average particle size of the aforementioned abrasive grains is preferably 300 nm, and more preferably 100 nm. Furthermore, in this specification, the average particle size of the abrasive grains is the primary particle size calculated using the specific surface area (m² / g) calculated by the BET (nitrogen adsorption) method.

[0056] From the viewpoint of achieving high grinding speed, the content of the aforementioned abrasive particles in the aforementioned grinding fluid composition is preferably 1% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. Regarding the upper limit of the aforementioned abrasive particle content, from the viewpoint of improving the smoothness of the object being ground, it is preferably 50% by mass, more preferably 45% by mass, and even more preferably 40% by mass. The preferred range of the aforementioned abrasive particle content can be expressed by any combination of these lower and upper limits. For example, the preferred range of the aforementioned abrasive particle content can be 1% by mass or more and 50% by mass, or 10% by mass or more and 45% by mass or less, or 15% by mass or more and 40% by mass or less.

[0057] The aforementioned polishing slurry composition may also contain a solvent. The solvent is preferably an aqueous solvent. Examples of aqueous solvents include water or mixtures of water and other solvents. Other solvents are preferably water-miscible, such as alcohols like ethanol. Furthermore, the aforementioned polishing slurry composition may contain known additives such as polishing accelerators, pH adjusters, surfactants, chelating agents, and corrosion inhibitors, without impairing the effects of the present invention.

[0058] The aforementioned polymer (P) content refers to the concentration of the solid component of the aforementioned polymer (P) relative to the total amount of the polishing slurry composition, preferably being 0.001% by mass or more, and more preferably 1% by mass or more. Regarding the upper limit of the aforementioned polymer (P) content, the concentration of the solid component of the polymer (P) relative to the total amount of the polishing slurry composition is preferably 10% by mass, and more preferably 5% by mass. The preferred range of the aforementioned polymer (P) content can be expressed by any combination of these lower and upper limits. For example, the preferred range of the aforementioned polymer (P) content, where the concentration of the solid component of the aforementioned polymer (P) relative to the total amount of the polishing slurry composition is either 0.001% by mass or less than 10% by mass, or 1% by mass or less than 5% by mass.

[0059] The aforementioned grinding fluid composition is prepared as a slurry mixture by mixing the various components using known methods. Although the viscosity of the aforementioned grinding fluid composition at 25°C can be appropriately selected according to the object being ground or the shear rate during grinding, it is preferably in the range of 0.1~10 mPa·s, and more preferably in the range of 0.5~5 mPa·s.

[0060] As an additive, the aforementioned polishing fluid composition contains the aforementioned polymer (P), which can make the polishing speed of the protrusions (oxide film) on the uneven surface of the object being polished sufficiently fast and greatly reduce the deformation of the depressions. Accordingly, the use of the aforementioned polishing slurry composition provided by the present invention in the manufacturing process of semiconductor devices, specifically in the planarization of the surface of at least one of insulating films and metal wiring, is suitable for, for example, the use of polishing slurries in the planarization of oxide films (silicon oxide films, etc.) during shallow trench isolation (STI) fabrication, the planarization of the surface of metal wiring made of copper or copper alloys, aluminum alloys, etc., and the planarization of the surface of interlayer insulating films (oxide films), thereby reducing the occurrence of defects and obtaining insulating films and metal wiring with excellent surface smoothness. [Example]

[0061] The present invention will now be specifically described with reference to embodiments. However, the present invention is not limited to these embodiments. Furthermore, unless otherwise stated, "parts" and "%" hereafter refer to parts by mass and percentage by mass. The analytical and manufacturing methods for the polymers used in the examples and comparative examples are described below.

[0062] <Molecular weight determination> Using a gel permeation chromatography apparatus (model name "HLC-8220", manufactured by Tosoh Corporation), the number average molecular weight (Mn) and weight average molecular weight (Mw) converted from polystyrene were obtained under the following conditions. Furthermore, the molecular weight dispersion (PDI), which is the ratio (Mw / Mn) of the number average molecular weight (Mn) to the weight average molecular weight (Mw), was calculated from the obtained values. • Measurement conditions Tube String: TSKgel SuperMultipore HxL-M×4 tube manufactured by Tosoh Corporation Column temperature: 40℃ Dissolution solution: Tetrahydrofuran Detector: RI Flow rate: 0.6 mL / min

[0063] <Polymer mass composition ratio> The mass composition ratio of the obtained polymer was calculated based on the reaction rate of the monomer as determined by 1H-NMR or gas chromatography (GC). The 1H-NMR measuring apparatus used was an Ascend™ 400 nuclear magnetic resonance measuring instrument manufactured by BRUKER Corporation. The measurement was performed at 25°C using tetramethylsilane as a standard and dichloroform as a solvent. Furthermore, for the GC determination, the apparatus used was an Agilent 7820A (manufactured by Agilent Technologies), the column used was a VARIAN CP-SIL 5CB (30m × 0.32mm, df = 3.0μm), the carrier gas was nitrogen, and the detection was performed using FID.

[0064] 1. Polymer Synthesis <Synthesis example 1> In a 1L four-necked flask equipped with a stirrer, thermometer, and nitrogen inlet tube, 150g of pure water, 300g of methoxy polyethylene glycol monoacrylate (Nippon Oil Manufacturing Co., Ltd., hereinafter referred to as "AME-400"), 0.48g of 4,4'-azobis(4-cyanopentanoic acid) (Fuji Film & Television and Wako Pure Chemical Industries Co., Ltd., hereinafter referred to as "V-501"), and 26.8g of 3-((((1-carboxyethyl)thio)thiocarbonyl)thio)propionic acid (BORON MOLECULAR Co., Ltd., hereinafter referred to as "BM1429") as a RAFT agent were added. After thorough degassing with nitrogen bubbling, polymerization was initiated by heating the flask in a 70°C constant temperature bath. After 3 hours, polymerization was stopped by water cooling of the flask. The polymerization rate of AME-400 at the point of polymerization cessation, determined by 1H-NMR, was 95%. Next, 15.6 g of ethyl acrylate (hereinafter referred to as "EA") was added to the flask, and the mixture was thoroughly degassed by nitrogen bubbling. The flask was then heated in a constant temperature bath at 70°C to begin polymerization. After 3 hours, the polymerization was stopped by water cooling of the flask. The polymerization rate of EA at the point of polymerization stop, as determined by GC, was 99%. The molecular weight of the water-soluble block copolymer obtained above (hereinafter referred to as "polymer A") was determined by GPC, with Mn of 3,030, Mw of 3,430, and PDI of 1.1.

[0065] <Synthetic Examples 2-22, 26-35, Comparative Synthetic Examples 2 and 6> Except for changing the raw materials to those shown in Tables 1 to 5, the same procedures as in Synthesis Example 1 were performed to obtain water-soluble block copolymers (polymers B to V, Z to i, m, and q). The molecular weights of polymers B to V, Z to i, m, and q, determined by GPC, are shown in Tables 1 to 5.

[0066] <Synthesis example 23> In a 1L four-necked flask equipped with a stirrer, thermometer, and nitrogen inlet tube, 150g of pure water, 300g of AME-400, 0.48g of V-501, and 25.4g of BM1429 were added. After thorough degassing with nitrogen bubbling, polymerization was initiated by heating the flask in a 70°C constant temperature bath. After 5 hours, polymerization was stopped by water cooling of the flask. The polymerization rate of AME-400 at the point of polymerization cessation, determined by 1H-NMR, was 99%. The molecular weight of the resulting water-soluble polymer (referred to as "polymer W") was determined by GPC, with Mn of 3,000, Mw of 3,390, and PDI of 1.1.

[0067] <Synthesis Examples 24~25> Except for changing the raw materials to those shown in Table 3, the same procedures as in Synthesis Example 23 were performed to obtain water-soluble polymers (polymers X and Y). The molecular weights of polymers X and Y determined by GPC are shown in Table 3.

[0068] <Synthesis example 36> In a 1L, four-necked, globular flask equipped with a stirrer, thermometer, and nitrogen inlet tube, 150g of pure water, 300g of AME-400, 0.48g of V-501, and 26.8g of BM1429 were added. After thorough degassing with nitrogen bubbling, polymerization was initiated by heating the flask in a 70°C constant temperature bath. After 3 hours, the polymerization was stopped by water cooling. The polymerization rate of AME-400, determined by 1H-NMR, was 95%. Next, 7.8g of EA was added to the flask, and after thorough degassing with nitrogen bubbling, polymerization was initiated by heating the flask in a 70°C constant temperature bath. After 3 hours, the polymerization was stopped by water cooling. The reaction rate of EA, determined by GC, was 95%. Next, 7.8 g of t-butylacrylamide (hereinafter referred to as "TBAM") was added to the flask. After thorough degassing with nitrogen bubbling, polymerization was initiated by heating the flask in a constant temperature bath at 70°C. After 3 hours, polymerization was stopped by water cooling the flask. The polymerization rate of TBAM, determined by GC, was 90%. The molecular weight of the resulting water-soluble block copolymer (hereinafter referred to as "polymer j"), determined by GPC, was Mn 3,120, Mw 3,490, and PDI 1.1.

[0069] <Synthesis Example 37> Except for changing the raw materials to those shown in Table 4, the same procedures as in Synthesis Example 36 were performed to obtain the water-soluble polymer k. The molecular weight of polymer k determined by GPC is shown in Table 4.

[0070] <Comparative Synthesis Example 1> Except for changing the raw materials to those shown in Table 5, the same procedures as in Synthesis Example 23 were performed to obtain water-soluble polymer 1. The molecular weight of polymer 1 determined by GPC is shown in Table 5.

[0071] <Comparative Synthesis Example 3> In a 1L four-necked flask equipped with a stirrer, thermometer, and nitrogen inlet tube, 100g of acetonitrile was added, and the mixture was kept at 75°C and stirred. Next, an initiator solution containing 0.10g of 2,2'-azobis(2,4-dimethylpentanonitrile) (manufactured by Fujifilm and Kohden Chemical Industries, hereinafter also referred to as "V-65") was added to the flask along with 7.2g of acetonitrile. Then, a chain transfer agent solution containing 432g of AME-400 and 50g of 3-mercaptopropionic acid 3-methoxybutyl ester (hereinafter also referred to as "MPMB") dissolved in 64g of acetonitrile was added to the flask over 3 hours. Simultaneously with the chain transfer agent solution, an initiator solution containing 0.40g of V-65 dissolved in 40g of acetonitrile was added to the flask over 5 hours. After the initiator solution was added, the contents of the flask were heated and stirred for another 1.5 hours. Finally, the polymerization was stopped by water cooling of the flask. The solvent was then removed from the contents of the flask using an evaporator. The polymerization rate of AME-400 at the point of polymerization cessation, determined by 1H-NMR, was 99%. The molecular weight of the resulting water-soluble polymer (referred to here as "polymer n") was determined by GPC, with Mn of 2,600, Mw of 5,720, and PDI of 2.2.

[0072] <Comparative Synthesis Examples 4-5> Except for changing the raw materials to those shown in Table 5, the same procedures as in Comparative Synthesis Example 3 were performed to obtain a water-soluble copolymer (polymer o~p). The molecular weight of polymer o~p determined by GPC is shown in Table 5.

[0073]

[0074]

[0075]

[0076]

[0077]

[0078] The details of the compounds shown in Tables 1 to 11 are as follows. AME-400: Methoxylated polyethylene glycol monoacrylate (n=9) (Japanese oil product, trade name: BLEMMER AME-400) PME-400: Methoxylated polyethylene glycol monomethacrylate (n=9) (Japanese oil manufacturer, trade name: BLEMMER PME-400) MTG-A: Methoxytriethylene glycol acrylate (Kyoei Chemical Co., Ltd., trade name: Light Acrylate MTG-A) AM-230G: Methoxylated polyethylene glycol acrylate (n=23) (manufactured by Shin-Nakamura Chemical Industry, trade name: NK ester AM-230G) AE-400: Polyolefin diol monoacrylate (n=10) (Nippon Oil Manufacturing, trade name: BLEMMER AE-400) EA: Ethyl acrylate NIPAM: N-Isopropylacrylamide ACMO: N-Acryloylmorpholine AA: Acrylic acid V-501: 4,4'-Azobis(4-Cyanopentaic acid) (manufactured by Fujifilm and Koko Pure Chemical Industries) V-65: 2,2'-Azobis(2,4-dimethylvalerate) (manufactured by Fujifilm and Waku Pure Chemical Industries) BM1429:3-((((1-Carboxyethyl)thio)thiocarbonyl (carbonothioyl) propionic acid (made by BORON MOLECULAR) MPMB: 3-Methoxybutyl 3-mercaptopropionic acid BA: n-Butyl acrylate MA: Methyl acrylate HexA: n-Hexyl acrylate TBAM:N-tert-butylacrylamide DMAA: N,N-dimethylacrylamide DEAA: N,N-Diethylacrylamide HEAA: N-(2-hydroxyethyl)acrylamide DPM-A: Methoxydipropylene glycol acrylate (Kyoei Chemical Co., Ltd., trade name: Light Acrylate DPM-A) HEA: 2-Hydroxyethyl acrylate XL-80: Polyoxyethylene branched decyl ether (surfactant manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd., trade name: NOIGEN (registered trademark) XL-80)

[0079] 2. Measurement and Evaluation <Example 1> Prepare 500 parts of an aqueous polymer solution containing polymer A at a solid content concentration of 0.5% by mass. Then, while stirring 500 parts of an aqueous dispersion of colloidal cerium dioxide (manufactured by NYACOL, trade name: NYACOL80 / 10, particle concentration 10%, average particle diameter 80nm), add the previously prepared aqueous polymer solution to obtain the grinding slurry composition.

[0080] <Examples 2-37, Comparative Examples 3-9> Except for changing polymer A to the polymers or surfactants shown in Tables 6 to 11, the same operation as in Example 1 was performed to obtain the grinding slurry composition.

[0081] <Example 38> 500 parts of an aqueous polymer solution containing polymer A at a solid content concentration of 0.5% by mass were prepared. Next, while stirring 500 parts of an aqueous dispersion of colloidal silica (manufactured by Fusang Chemical Industry Co., Ltd., trade name: Quartron PL-7, particle concentration 23%, average particle diameter 75 nm), the previously prepared aqueous polymer solution was added to obtain a grinding slurry composition adjusted to pH 9 with 28% ammonia. Note: "Quartron" is a registered trademark of Fusang Chemical Industry Co., Ltd.

[0082] <Example 39> Except for changing polymer A to the polymer shown in Table 10, the same operations as in Example 38 were performed to obtain the grinding slurry composition.

[0083] <Comparative Example 1> While stirring 500 parts of an aqueous dispersion of colloidal cerium dioxide (manufactured by NYACOL, trade name: NYACOL80 / 10, particle concentration 10%, average particle diameter 80nm), 500 parts of pure water were added to obtain the grinding slurry composition.

[0084] <Comparative Example 2> While stirring 500 parts of an aqueous dispersion of colloidal silica (manufactured by Fuso Chemical Industry, trade name: Quartron PL-7, particle concentration 23%, average particle diameter 75nm), 500 parts of pure water were added to obtain a grinding slurry composition adjusted to pH 9 with 28% ammonia.

[0085] Using the various grinding fluid compositions prepared by the above method, grinding tests were conducted under the following conditions. <Polishing Conditions> Polishing tester: manufactured by Kemet Japan, product name: MAT-ARW-CMS Polishing pad: manufactured by Rodel Nitta, product name: IC-1000 / Sub400 Platen rotation speed: 60 rpm Carrier rotation speed: 61 rpm Polishing liquid supply rate: 150 g / min Polishing pressure: 1 psi, 3 psi or 5 psi

[0086] <RR Measurement / Evaluation Method> A control chip coated wafer with 1.4 μm thick silicon oxide formed by CVD on a 4-inch silicon substrate was used as the material to be polished, and polished for 1 minute under the above polishing conditions. The polishing rate (RR) (unit: nm / min) was calculated from the difference in the remaining film thickness before and after polishing. The remaining film thickness was measured using an optical interference film thickness meter. For the RR of each polishing liquid composition, the RR of the polishing liquid compositions of Examples 1 to 37 and Comparative Examples 3 to 9 was evaluated as a ratio to the RR of the polishing liquid composition of Comparative Example 1. The RR of the polishing liquid compositions of Examples 38 to 39 was evaluated as a ratio to the RR of the polishing liquid composition of Comparative Example 2 (at 3 psi for both). The evaluation criteria for RR are as follows. (Let the RR of Comparative Examples 1 to 2 be RRa, and the RR of the polishing liquid compositions of Examples 1 to 37 and Comparative Examples 3 to 9 be RRb. The calculated values of RRb / Rra are shown in Tables 6 to 11). For Comparative Examples 1 to 2, the polishing liquid compositions were set as RRb / RRa = 1.00. Next, for the recess reduction performance, based on the ratio of the RR at 3 psi (RR3) to the RR at 1 psi (RR1) (RR3 / RR1) and the ratio of the RR at 5 psi (RR5) to RR1 (RR5 / RR1), the evaluation was carried out according to the following criteria. The case where both criteria C or above for RR and recess reduction performance were satisfied was defined as qualified. <Evaluation Criteria for RR> A: RRb / RRa ≥ 0.85 B: 0.85 > RRb / RRa ≥ 0.70 C: 0.70 > RRb / RRa ≥ 0.50 D: RRb / RRa < 0.50 <Evaluation Criteria for Recess Reduction Performance> A: RR3 / RR1 ≥ 4.0 and RR5 / RR1 ≥ 7.0 B: 4.0 > RR3 / RR1 > 3.5 or 7.0 > RR5 / RR1 > 6.5 C: 3.5 ≥ RR3 / RR1 > 3.0 or 6.5 ≥ RR5 / RR1 > 5.2 D: RR3 / RR1≦3.0 and RR5 / RR1≦5.2

[0087] <Evaluation Results> The polishing of control-coated wafers using the polishing slurry compositions of each embodiment will be shown in Tables 6 to 11, with respect to the RR (RR1, RR3, RR5) of each polishing pressure, the RRb / RRa value of the RR evaluation index, and the RR3 / RR1 and RR5 / RR1 values ​​of the indentation reduction performance evaluation index. A polishing slurry composition that suppresses RR at low polishing pressure and exhibits high RR at high polishing pressure can produce a good polished surface that reduces the depressions of patterned wafers without reducing RR. In the examples, each polishing fluid composition suppressed RR at low polishing pressure, but exhibited high RR at high polishing pressure, with increased RR3 / RR1 and RR5 / RR1. Furthermore, due to the small reduction in RR3, RRb / Rra also increased. In contrast, Comparative Examples 1 and 2, without additives, showed RR almost proportional to the polishing pressure. In Comparative Examples 4, 5, and 9, RR was significantly suppressed at full polishing pressure, but both RR and indentation reduction performance failed to meet the acceptable standards. In Comparative Examples 3, 6-8, although relatively high RR was observed at various polishing pressures, the indentation reduction performance was insufficient because RR was not significantly suppressed at low polishing pressures.

[0088]

[0089]

[0090]

[0091]

[0092]

[0093]

Claims

1. An additive for chemical mechanical polishing, comprising a polymer (P), characterized in that the polymer (P) contains structural units (A) derived from vinyl monomers having a -(LO)nR group and structural units (B) derived from vinyl monomers having an amino group (excluding the aforementioned vinyl monomers having a -(LO)nR group), and the total content of structural units derived from monomers having one or more functional groups selected from the group consisting of carboxylic acid group, phosphate group, phosphonic acid group, sulfate group, sulfonic acid group and salts thereof is 0 to 0.6% by mass, and the dispersion (PDI) of the polymer (P) expressed as weight average molecular weight (Mw) / number average molecular weight (Mn) is 2.0 or less (where L is an alkyl group having 4 or fewer carbon atoms, n is any integer from 3 to 150, and R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms).

2. The additive as requested in item 1, wherein, The number average molecular weight (Mn) of the aforementioned polymer (P) is 1,000 to 100,000.

3. The additive as requested in item 1, wherein, The aforementioned building unit (B) is a building unit derived from (meth)acrylate and / or (meth)acrylate amine type monomers.

4. The additive as requested in item 1, wherein, The aforementioned structural unit (B) is a structural unit derived from a monomer with an SP value of 17 to 25 (J / cm3) 0.5 calculated by Fedors' estimation method.

5. The additive as requested in item 1, wherein, The aforementioned polymer (P) is a block polymer.

6. The additives as requested in item 5, wherein, The aforementioned polymer (P) contains polymer block A and polymer block B, wherein the aforementioned polymer block A has the aforementioned building block (A) and the aforementioned polymer block B has the aforementioned building block (B).

7. The additives as requested in item 6, wherein, The ratio (A / B) of the aforementioned polymer (P) to the aforementioned polymer block A and the aforementioned polymer block B is 50 / 50 to 99.9 / 0.1 by mass.

8. An abrasive slurry composition for chemical mechanical polishing of at least one of an insulating layer and a wiring layer for surface planarization, comprising an additive as described in any one of claims 1 to 7, and cerium oxide and / or silicon dioxide.

9. A method for manufacturing an additive for chemical mechanical polishing slurries comprising a polymer, characterized in that the polymer contains structural units derived from vinyl monomers having a -(LO)nR group and structural units derived from vinyl monomers containing an amino group (excluding the aforementioned vinyl monomers having a -(LO)nR group), and the total content of structural units derived from monomers containing one or more functional groups selected from the group consisting of carboxylic acid groups, phosphate groups, phosphonic acid groups, sulfate groups, sulfonic acid groups and salts thereof is 0 to 0.6% by mass, and the method includes a step of manufacturing the polymer by living radical polymerization, wherein the polymer has a dispersion (PDI) of 2.0 or less as expressed as the weight average molecular weight (Mw) / number average molecular weight (Mn) of the aforementioned polymer (where L is an alkyl group having 4 or fewer carbon atoms, n is any integer from 3 to 150, and R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 4 carbon atoms).