Method for producing composite particles in which the core is coated with cerium oxide particles, and composite particles manufactured thereby

Abstract

A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, a composite particle manufactured by said method, and a chemical mechanical planarization composition comprising said composite particle are disclosed. The composite particle manufactured by said method in which the core is coated with cerium oxide particles does not include a hydrothermal synthesis process during manufacturing, and thus contains a high proportion of Ce3+ on the particle surface, which can exhibit a high polishing rate.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing a composite particle in which a core is coated with cerium oxide particles, a composite particle manufactured by said method, and a chemical mechanical planarization composition comprising said composite particle. Background Technology

[0003] Chemical mechanical planarization slurries are widely used to planarize semiconductor wafers or integrated circuits (ICs) and other substrates for semiconductor fabrication. Generally, these slurries contain reactive chemicals such as oxidizers, complexing agents, and mechanical abrasive particles such as SiO2, CeO2, and Al2O3. Among these, CeO2 (cerium oxide) has received significant attention due to its excellent hardness, high polishing rate, and unique oxidizing ability.

[0004] It is widely accepted that the size, shape, and composition of abrasive particles play a crucial role in determining polishing rates and surface quality. With the development of semiconductor chips featuring smaller nodes, very fine abrasive particles have garnered significant attention. On the one hand, while large particles provide high removal rates, they cause micro-scratches on the substrate surface and result in a deteriorated surface finish. On the other hand, cerium oxide particles smaller than 50 nm exhibit better surface finish quality but have very low polishing rates. Furthermore, nano-sized cerium oxide particles aggregate more easily than other types of particles, such as silica, alumina, and zirconia, resulting in insufficient dispersion in water.

[0005] Meanwhile, abrasive slurries mixed with two or more inorganic metal oxides have non-uniformity in particle size, which poses a risk of scratching and causes problems when used as CMP abrasives.

[0006] In particular, during the manufacturing of silica slurries coated with ceria, a cerium oxide, aggregation occurs between particles during the heating process that converts amorphous ceria precursors into crystalline ceria. This results in low particle size uniformity, leading to problems such as a low polishing rate and scratches. Since the ceria preparation method on silica surfaces using precursors crystallizes into cerium oxide particles from the liquid phase, the degree of crystallization of the resulting cerium oxide particles is relatively low. Furthermore, cerium oxide does not adhere well to core particles and remains on the surface of composite particles, which can affect the polishing rate. Therefore, there is a need to develop CMP abrasive composite particles that can compensate for the aforementioned disadvantages.

[0007] Now, while researching to solve the above-mentioned problem, the inventors confirmed that when a composite particle is manufactured by mixing a cerium oxide particle dispersion with a core particle dispersion and adjusting the pH, an additional calcination process is not required, thereby maintaining the polishing characteristics of the cerium oxide particles themselves and allowing the polishing speed to be controlled according to the size of the core particles, thus completing the present invention.

[0008] In this regard, Korean registered patent No. 10-1581462 discloses a mesoporous silica / ceria-silica composite and a method for manufacturing the same. The problem to be solved

[0010] The present invention is designed to solve the aforementioned problems, and one embodiment of the present invention provides a method for manufacturing a composite particle in which a core is coated with cerium oxide particles.

[0011] In addition, another embodiment of the present invention provides a composite particle in which a core manufactured by the above manufacturing method is coated with cerium oxide particles.

[0012] In addition, another embodiment of the present invention provides a chemical mechanical planarization composition comprising a composite particle in which the core is coated with cerium oxide particles.

[0013] The technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0015] As a technical means for achieving the aforementioned technical problem, one aspect of the present invention is,

[0016] A method for manufacturing a composite particle having a core coated with cerium oxide particles is provided, wherein the method comprises: a) preparing a core particle dispersion and a cerium oxide particle dispersion; b) mixing the core particle dispersion and the cerium oxide particle dispersion to prepare a mixed dispersion; and c) adding a pH adjuster to the mixed dispersion and stirring.

[0017] Cerium oxide particles may be characterized by being manufactured by a group of methods consisting of the liquid phase method, the calcination method, and combinations thereof.

[0018] Steps a) to c) above may be characterized by being performed at a temperature of 15 ℃ to 85 ℃.

[0019] The above pH adjuster may be characterized by being selected from the group consisting of ammonia water, imidazole, hexamethylenetetramine, aminobutyric acid, lysine, arginine, histidine, triethanolamine, diethanolamine, tetramethylammonium hydroxide, potassium hydroxide, sodium hydroxide, and combinations thereof.

[0020] The pH adjusted by the above pH adjuster may be characterized as being 3 to 11.

[0021] The core particles may be characterized by being selected from the group consisting of silica (SiO2), alumina (Al2O3), ceria (CeO2), zirconia (ZrO2), titania (titanium oxide), zeolite, polystyrene, polymethacrylate, and combinations thereof.

[0022] The above core particles may be characterized as being colloidal silica.

[0023] The above core particles may be characterized by having an average particle size of 20 nm to 150 nm.

[0024] The above cerium oxide particles may be characterized by having an average particle size of 2 nm to 20 nm.

[0025] The above cerium oxide particles may be characterized by being mixed in an amount of 1 to 150 parts by weight relative to 100 parts by weight of the core particles.

[0026] The stirring in step c) above may be characterized by being performed for 1 to 12 hours.

[0027] The above pH adjuster may be characterized by being added in an amount of 0.1 to 10 parts by weight relative to 100 parts by weight of the core particles.

[0028] The above manufacturing method may be characterized by further including a step of centrifuging and washing to disperse after step c).

[0030] In addition, another aspect of the present invention is,

[0031] A composite particle is provided in which a core manufactured by the method according to one aspect above is coated with cerium oxide particles.

[0032] The above composite particle may be characterized by having 1 to 50 parts by weight of cerium oxide particles per 100 parts by weight of core particles.

[0033] The composite particle in which the core is coated with cerium oxide particles may be characterized by having a standard deviation according to the particle size distribution of 20% or less of the diameter of the composite particle.

[0034] The above cerium oxide particles are Ce 4+ and Ce 3+ Includes, and the above Ce 4+ and Ce 3+ It may be characterized by a weight ratio of 1:0.2 to 0.8.

[0035] The above composite particle may be characterized by having a positive zeta potential of 10 mV to 50 mV.

[0037] In addition, another aspect of the present invention is,

[0038] The present invention provides a chemical mechanical planarization composition comprising a composite particle in which the core is coated with cerium oxide particles.

[0039] The chemical mechanical planarization composition may be characterized by comprising 0.1% to 5% by weight of a composite particle in which the core is coated with cerium oxide particles.

[0040] The above chemical mechanical planarization composition may be characterized by having a pH in the range of 3 to 11. Effects of the invention

[0042] According to one embodiment of the present invention, the composite particle manufactured by the method for manufacturing a composite particle in which the core is coated with cerium oxide particles does not include a hydrothermal synthesis process during manufacturing, and thus has a high proportion of Ce on the particle surface of the cerium oxide particles. 3+ It can exhibit a high polishing rate by containing [it].

[0043] In addition, the method for manufacturing a composite particle in which the core is coated with cerium oxide particles according to one embodiment of the present invention allows for easy control of reaction conditions and is simple.

[0044] Furthermore, through a manufacturing method according to one embodiment of the present invention, composite particles having a desired particle size distribution can be manufactured by selecting the size of the silica core particles. In addition, composite particles having a desired particle size distribution can be selectively manufactured by controlling the type of base used for precipitation during manufacturing, the concentration of the base, or the reaction temperature. The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the composition of the invention described in the detailed description of the present invention or the claims. Brief explanation of the drawing

[0046] FIG. 1 is a schematic diagram showing a method for manufacturing a composite particle in which a core is coated with cerium oxide particles according to one embodiment of the present invention. FIG. 2 is a diagram showing an example of a flowchart of a method for manufacturing a composite particle in which a core is coated with cerium oxide particles according to one embodiment of the present invention. FIG. 3 is a drawing showing an SEM image of cerium oxide particles manufactured according to one embodiment of the present invention. FIG. 4 is a drawing showing an SEM image of a composite particle in which a core is coated with cerium oxide particles according to one embodiment of the present invention. FIG. 5 is a drawing showing (a) composite particles of Example 1-1 and Example 2-1, (b) composite particles of Example 1-2 and Example 3-2, and (c) composite particles of Comparative Example 1 and Comparative Example 2 according to one embodiment of the present invention. FIG. 6 is a diagram showing the EDS experimental results of (a) composite particles of Example 1-1 and Example 2-1, and (b) composite particles of Example 1-2 and Example 3-2 according to one embodiment of the present invention. FIG. 7 is a diagram showing the XPS experimental results of the composite particles of Example 1-2 according to one embodiment of the present invention. Specific details for implementing the invention

[0047] The present invention will be described in more detail below. However, the present invention may be implemented in various different forms and is not limited by the embodiments described herein, and is defined only by the claims set forth below.

[0048] Additionally, the terms used in this invention are used merely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. Throughout the specification of this invention, the term 'comprising' any component means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0050] The first aspect of the present invention is,

[0051] A method for manufacturing a composite particle having a core coated with cerium oxide particles is provided, wherein the method comprises: a) preparing a core particle dispersion and a cerium oxide particle dispersion; b) mixing the core particle dispersion and the cerium oxide particle dispersion to prepare a mixed dispersion; and c) adding a pH adjuster to the mixed dispersion and stirring.

[0053] Hereinafter, a method for manufacturing a composite particle in which the core is coated with cerium oxide particles according to the first aspect of the present invention will be described in detail step by step.

[0055] First, in one embodiment of the present invention, the method for manufacturing the composite particles comprises a) a step of preparing a core particle dispersion and a cerium oxide particle dispersion. The core particle dispersion and the cerium oxide particle dispersion have the core particles dispersed in water and / or an organic solvent. The organic solvent is preferably an alcohol such as methyl alcohol, ethyl alcohol, isopropyl alcohol, etc., and other water-soluble organic solvents such as ethers, esters, ketones, etc. may be used, and preferably water may be used.

[0056] In one embodiment of the present invention, the core particles may be characterized by being selected from the group consisting of silica (SiO2), alumina (Al2O3), ceria (CeO2), zirconia (ZrO2), titania (titanium oxide), zeolite, polystyrene, polymethacrylate, and combinations thereof, and preferably may be colloidal silica. In one embodiment of the present invention, the core particles may be characterized by having an average particle size of 20 nm to 150 nm. If the core particles are less than 20 nm, the polishing rate may decrease, and if the core particles are more than 150 nm, there may be a problem with reduced stability of the slurry when preparing a polishing slurry.

[0057] In one embodiment of the present invention, the cerium oxide particles may be characterized by having an average particle size of 2 nm to 20 nm. If the cerium oxide particles are less than 2 nm, the insulating film polishing rate is very low, and if they exceed 20 nm, there may be problems with scratches and defects.

[0059] In one embodiment of the present invention, the cerium oxide particles may be characterized by being manufactured by a method of the group consisting of a liquid phase method, a calcination method, and combinations thereof, and preferably may be manufactured by a liquid phase method.

[0061] Next, in one embodiment of the present invention, the manufacturing method comprises the step of b) mixing the core particle dispersion and the cerium oxide particle dispersion to produce a mixed dispersion. In one embodiment of the present invention, the cerium oxide particles may be mixed in an amount of 1 to 150 parts by weight relative to 100 parts by weight of the core particles. If the cerium oxide particles are mixed in an amount of less than 1 part by weight relative to 100 parts by weight of the core particles, it is difficult to sufficiently bind the cerium oxide particles to the core particles, making it difficult to obtain the desired effect. If the amount exceeds 150 parts by weight, there may be a problem of reduced economic efficiency because the efficiency does not increase further relative to the amount of core particles added.

[0063] In one embodiment of the present invention, the method for manufacturing the composite particles comprises: c) adding a pH adjuster to the mixed dispersion and stirring. In one embodiment of the present invention, the pH adjuster may be selected from the group consisting of water ammonia, imidazole, hexamethylenetetramine aminobutyric acid, lysine, arginine, histidine, triethanolamine, diethanolamine, tetramethylammonium hydroxide, potassium hydroxide, sodium hydroxide, and combinations thereof, and the pH adjuster may be added in an amount of 0.1 to 100 parts by weight per 100 parts by weight of the core particles. Preferably, the pH adjuster may be added in an amount of 1 to 80 parts by weight per 100 parts by weight of the core particles, and more preferably in an amount of 5 to 70 parts by weight. If the above pH adjuster is added in an amount of less than 0.1 parts by weight per 100 parts by weight of the core particles, the pH may be lower than the optimal value, which may cause a problem where the ceria particles do not adhere to the surface of the silica particles; if it is added in an amount exceeding 100 parts by weight, the pH may be higher than the optimal value, which may cause a problem of particle aggregation. Additionally, the pH adjusted by the above pH adjuster may be characterized as being 3 to 11. Preferably, the pH adjusted by the above pH adjuster may be 4 to 10, and more preferably, the pH may be 5 to 10. If the pH falls outside the above pH range, there is a concern that the cerium oxide particles may not be properly coated on the core particles.

[0064] In one embodiment of the present invention, the stirring in step c) may be characterized as being performed for 1 to 12 hours. Preferably, stirring may be performed for 1 to 8 hours, and more preferably for 2 to 4 hours. If stirring is performed for less than 1 hour, there may be a problem in that the coating of the cerium oxide particles on the core particles is not sufficiently achieved, and if it is performed for more than 12 hours, economic efficiency is reduced.

[0066] In one embodiment of the present invention, steps a) to c) may be characterized by being performed at a temperature of 15°C to 85°C. Preferably, they may be performed in a temperature range of 15°C to 75°C, and more preferably in a temperature range of 15°C to 55°C. If performed at a temperature below 15°C, it is not economical because it takes a long time for the coating to occur, and if performed at a temperature above 85°C, it is difficult to control the coating speed, and aggregation between particles occurs, resulting in low particle size uniformity and a risk of scratching.

[0068] In one embodiment of the present invention, the manufacturing method may further include a step of centrifuging, washing, and dispersing (d) after step c). Step d) may involve separating the composite particles generated in the mixed solution by centrifugation, washing with a solvent, and dispersing. The washing is intended to remove the pH adjuster and residual cerium oxide particles remaining on the surface of the composite particles after the reaction. If the washing is not performed properly, the pH adjuster may remain on the surface of the composite particles, which may reduce the dispersibility of the particles during the preparation of the chemical mechanical composition and hinder the realization of the polishing selectivity. The washing process is performed at least once, and 3 to 10 times is preferred. The dispersion method may be carried out using an ultrasonic cleaner. The dispersion is performed until the dispersion solution is sufficiently dispersed, and the dispersion method is not particularly limited.

[0070] The second aspect of the present invention is,

[0071] A composite particle is provided in which a core manufactured by the method according to the first aspect above is coated with cerium oxide particles.

[0073] Detailed explanations have been omitted for parts that overlap with the first aspect of the present invention, but the content described in the first aspect of the present invention may be applied in the same way even if such explanations are omitted in the second aspect.

[0075] Hereinafter, a composite particle in which a core according to the second aspect of the present invention is coated with cerium oxide particles will be described in detail.

[0077] In one embodiment of the present invention, the composite particle may be characterized by having 1 to 100 parts by weight of cerium oxide particles per 100 parts by weight of core particles. Preferably, the composite particle may have 2 to 80 parts by weight of cerium oxide particles per 100 parts by weight of core particles, more preferably 4 to 50 parts by weight. If the weight of cerium oxide particles per 100 parts by weight of core particles of the composite particle is less than 1, there may be a problem that the polishing effect of the composite particle is reduced because the amount of cerium oxide particles coating the surface of the core particles is small, and if it exceeds 100, there may be a problem of non-uniformity in particle size distribution.

[0078] In one embodiment of the present invention, the composite particle, in which the core is coated with cerium oxide particles, may be characterized in that the standard deviation according to the particle size distribution is 20% or less of the diameter of the composite particle. Preferably, the standard deviation may be 15% or less of the diameter of the composite particle, and more preferably 10% or less. If the standard deviation according to the particle size distribution of the composite particle exceeds 20% of the diameter of the composite particle, the particle size distribution is uneven, and there may be a problem with polishing.

[0079] In one embodiment of the present invention, the cerium oxide particles are Ce 4+ and Ce 3+ Includes, and the above Ce 4+ and Ce 3+ The weight ratio of may be characterized as being 1:0.2 to 0.8. Preferably, it may be 1:0.25 to 0.7, and more preferably 1:0.3 to 0.6. If the above Ce 4+ and Ce 3+ When the weight ratio is lower than 0.2 to 1:0.2, the oxide film removal rate decreases and it is difficult to secure the target amount of polishing, and when it is greater than 0.8, there is a problem that it is difficult to secure dispersibility.

[0080] In one embodiment of the present invention, the composite particle may be characterized by having a positive zeta potential of 10 mV to 50 mV, preferably 10 mV to 40 mV.

[0082] The third aspect of the present invention is,

[0083] The present invention provides a chemical mechanical planarization composition comprising a composite particle in which the core is coated with cerium oxide particles.

[0085] Detailed descriptions of parts that overlap with the first and second aspects of the present invention have been omitted, but the descriptions of the first and second aspects of the present invention may be applied in the same way even if such descriptions are omitted in the third aspect.

[0087] Hereinafter, a chemical mechanical planarization composition comprising a composite particle in which the core is coated with cerium oxide particles according to the third aspect of the present invention will be described in detail.

[0089] In one embodiment of the present invention, the chemical mechanical planarization composition may be characterized by comprising 0.1% to 5% by weight of a composite particle in which the core is coated with cerium oxide particles. Preferably, the chemical mechanical planarization composition may comprise 0.1% to 4% by weight of the composite particle, and more preferably, may comprise 0.2% to 2% by weight. If the composition comprises less than 0.1% by weight of the composite particle, there is a risk that the planarization rate will be reduced because the film to be polished cannot be sufficiently polished during polishing, and if it comprises more than 5% by weight, there is a risk that it will cause defects such as defects and scratches.

[0090] In one embodiment of the present invention, the polishing rate of the chemical mechanical planarization composition may be characterized as being 1,000 Å / min or higher. Preferably, the polishing rate of the composition may be 1,500 Å / min or higher, and more preferably 2,000 Å / min or higher.

[0091] In one embodiment of the present invention, the pH of the chemical mechanical planarization composition may be characterized as being in the range of 3 to 11, preferably 4 to 9, and more preferably 4 to 7. When the pH is within the above pH range, the dispersion stability and polishing performance of the composite particles may be improved, and the precipitation or aggregation of the composite particles that may occur due to a sudden change in pH (pH Shock) may be prevented, thereby minimizing the occurrence of micro-scratches that may be induced during the polishing process.

[0093] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0095] Preparation Example. Preparation of cerium oxide particles

[0096] Cerium oxide particles were prepared for the manufacture of a composite particle in which a core according to the present invention is coated with cerium oxide particles, and this is shown in FIG. 3.

[0097] Cerium oxide in an isometric form was prepared with a primary particle size of 1 to 5 nm and an average particle diameter of about 3 to 7 nm. The cerium oxide particles were manufactured by growing the particles through chemical synthesis using a bottom-up method. Chemical synthesis methods for cerium oxide particles may include the sol-gel method, supercritical reaction, hydrothermal reaction, and co-precipitation method, and all syntheses included ammonium-based additives to control the shape of the cerium particles.

[0099] Example. Preparation of composite particles with a core coated with cerium oxide particles

[0100] A composite particle in which the core according to the present invention is coated with cerium oxide particles was manufactured and is shown in FIG. 4.

[0101] Commercially available colloidal silica with an average particle size of 40 or 120 nm was used as the core particles, and a core particle dispersion was prepared by dispersing 8 g of colloidal silica in 320 g of deionized water using an ultrasonic grinder for 10 minutes. A cerium oxide particle dispersion was prepared by stirring and dispersing 2.67 g of the cerium oxide particles prepared in the above preparation example in 640 g of deionized water. Next, a mixed dispersion was prepared by mixing the core particle dispersion and the cerium oxide particle dispersion and stirring for 10 minutes. A pH adjuster was added to the mixed dispersion to adjust the pH, and the mixture was stirred for 2 hours. After stirring and reaction, the mixed dispersion was centrifuged and washed to obtain composite particles in which the core was coated with cerium oxide particles.

[0103] Example 1. Preparation of composite particles using ammonia water as a pH adjuster

[0104] Example 1-1. Preparation of composite particles using colloidal silica with an average particle size of 40 nm as core particles

[0105] In the above example, colloidal silica with an average particle size of 40 nm was used as the core particle, 4 g of ammonia water at a concentration of 10% was added as a pH adjuster to adjust the pH to 10, and the manufacturing temperature was set to room temperature to obtain a composite particle in which the core was coated with cerium oxide particles.

[0107] Example 1-2. Preparation of composite particles using colloidal silica with an average particle size of 120 nm as core particles

[0108] It was prepared in the same manner as Example 1-1 above, except that colloidal silica with an average particle size of 120 nm was used instead of colloidal silica with an average particle size of 40 nm as the core particle.

[0110] Example 2. Preparation of composite particles using hexamethylenetetramine as a pH adjuster

[0111] Example 2-1. Preparation of composite particles using colloidal silica with an average particle size of 40 nm as core particles

[0112] In the above example, colloidal silica with an average particle size of 40 nm was used as the core particle, 4 g of hexamethylenetetramine was added as a pH adjuster to adjust the pH to 6.5, and the manufacturing temperature was set to room temperature to obtain a composite particle in which the core was coated with cerium oxide particles.

[0114] Example 2-2. Preparation of composite particles using colloidal silica with an average particle size of 120 nm as core particles

[0115] It was prepared in the same manner as Example 2-1 above, except that colloidal silica with an average particle size of 120 nm was used as the core particle instead of colloidal silica with an average particle size of 40 nm.

[0117] Example 3. Preparation of composite particles using imidazole as a pH adjuster

[0118] Example 3-1. Colloidal silica with an average particle size of 40 nm as core particles cast Preparation of the composite particles used

[0119] In the above example, colloidal silica with an average particle size of 40 nm was used as the core particle, 4 g of imidazole was added as a pH adjuster to adjust the pH to 7.8, and the manufacturing temperature was set to room temperature to obtain a composite particle in which the core was coated with cerium oxide particles.

[0121] Example 3-2. Colloidal silica with an average particle size of 120 nm as core particles Preparation of the composite particles used

[0122] It was prepared in the same manner as Example 3-1 above, except that colloidal silica with an average particle size of 120 nm was used as the core particle instead of colloidal silica with an average particle size of 40 nm.

[0124] Example 4. Preparation of composite particles using cerium oxide particles and a pH adjuster at 75 °C

[0125] It was manufactured in the same manner as Example 2-1 above, except that the manufacturing temperature was set to 75 ℃ instead of room temperature.

[0127] Comparative Example 1. Preparation of composite particles using a cerium oxide precursor

[0128] In Comparative Example 1, unlike in the example where composite particles were prepared using cerium oxide particles, composite particles were prepared using a cerium nitrate precursor.

[0129] Manufacturing method

[0130] A core particle dispersion was prepared by dispersing 8 g of colloidal silica with an average particle size of 40 nm as core particles in 320 g of deionized water using an ultrasonic grinder for 10 minutes. A cerium precursor dispersion was prepared by stirring and dispersing 2.67 g of cerium nitrate as a cerium precursor in 640 g of deionized water. Next, a mixed dispersion was prepared by mixing the core particle dispersion and the cerium oxide particle dispersion and stirring for 10 minutes. 4.0 g of hexamethylenetetramine was added to the mixed dispersion as a pH adjuster to adjust the pH to 6.5, and the mixture was stirred for 2 hours. After stirring, the reaction mixture was centrifuged and washed to obtain composite particles in which the core was coated with cerium oxide particles.

[0132] Comparative Example 2. Preparation of composite particles not containing a pH adjuster

[0133] A core particle dispersion was prepared by dispersing 8 g of colloidal silica with an average particle size of 40 nm as core particles in 320 g of deionized water using an ultrasonic grinder for 10 minutes. A cerium oxide particle dispersion was prepared by stirring and dispersing 2.67 g of the cerium oxide particles prepared in the above preparation example in 640 g of deionized water. Next, a mixed dispersion was prepared by mixing the core particle dispersion and the cerium oxide particle dispersion and stirring for 2 hours. The mixed dispersion after the reaction was centrifuged and washed to obtain composite particles in which the core was coated with cerium oxide particles. At this time, the preparation temperature was 75 ℃ and the pH was 3.0.

[0135] experiment silica core particles Cerium oxide coating particles pH adjuster Preparation pH Manufacturing temperature Comparative Example 1 Colloidal silica with an average particle size of 40 nm Cerium nitrate precursor HMTA 6.5 75˚C Comparative Example 2 Colloidal silica with an average particle size of 40 nm nano-ceria particles - 3.0 75˚C Example 1-1 Colloidal silica with an average particle size of 40 nm nano-ceria particles ammonia 10.0 room temperature Example 2-1 Colloidal silica with an average particle size of 40 nm nano-ceria particles HMTA 6.5 room temperature Example 3-1 Colloidal silica with an average particle size of 40 nm nano-ceria particles Imidazole 7.8 room temperature Example 4 Colloidal silica with an average particle size of 40 nm nano-ceria particles HMTA 6.5 75˚C Examples 1-2 Colloidal silica with an average particle size of 120 nm nano-ceria particles ammonia 10.0 room temperature Example 2-2 Colloidal silica with an average particle size of 120 nm nano-ceria particles HMTA 6.5 room temperature Example 3-2 Colloidal silica with an average particle size of 120 nm nano-ceria particles Imidazole 7.8 room temperature

[0137] Experimental Example 1. Experiment confirming the coating of composite particles using SEM and EDS

[0138] First, the coating of the composite particles prepared through the above examples and comparative examples was verified using SEM. After Pt coating the samples with E-1045 Ion Sputter using a Hitachi S-4800 instrument, the particle size and characteristics were analyzed, and the presence of cerium was analyzed using a HORIBA EMAX x-act EDS instrument. As shown in Fig. 5(a), it was confirmed that silica particles with a diameter of 40 nm were coated with ceria particles with a thickness of 10 nm or more and dispersed in a uniform size. As shown in Fig. 5(b), when silica particles with a diameter of 120 nm were used, it was confirmed that they were coated with ceria particles with a thickness of 10 nm or more and dispersed in a uniform size. Through this, it was confirmed that cerium oxide particles were coated on the surface of the silica core particles in the composite particles of Examples 1 to 3. On the other hand, as shown in the SEM results of Comparative Examples 1 and 2 in Fig. 5(c), Comparative Example 1 did not show distinct coated characteristics of the ceria particles and contained a significant amount of aggregation of ceria particles existing alone rather than on the silica surface. Comparative Example 2 showed that aggregation of cerium oxide occurred and the size of the composite particles was non-uniform.

[0139] Next, to confirm the coating of cerium oxide particles on the core of the composite particles of Examples 1 to 3, EDS elemental analysis of the surface was performed and the results are shown in Fig. 6. Fig. 6(a) shows the results confirming the presence of cerium in the coating layer of the 40 nm core composite particles prepared in Examples 1-1 and 2-1, and Fig. 6(b) shows the results confirming the presence of cerium in the coating layer of the 120 nm core composite particles prepared in Examples 1-2 and 2-2. As a result of the EDS elemental analysis, a Ce peak was detected, thereby confirming the cerium oxide coating of the composite particles of Examples 1 to 3.

[0141] Experimental Example 2. Experiment to verify the average particle size and standard deviation of composite particles

[0142] To confirm the average particle size and standard deviation of Examples 1 to 3 and Comparative Examples, an evaluation was conducted using SEM analysis, and the results are shown in Table 2. As shown in Table 2, the average particle size of Examples 1-1 to 3-1, which used colloidal silica particles with an average particle size of 40 nm, was smaller than the average particle size of the composite particles of Examples 1-2 to 3-2, which used colloidal silica particles with an average particle size of 120 nm. Through this, it was confirmed that the average particle size of the composite particles can be controlled according to the size of the silica core particles.

[0143] Meanwhile, the standard deviation of the average particle size in Examples 1 to 3 was found to be smaller when compared to colloidal silica particles with an average particle size of 40 nm, confirming that they had a uniform particle size distribution. On the other hand, in the case of Comparative Examples 1 and 2 using a cerium nitrate precursor, the standard deviation was larger than that of the Examples, and it was confirmed that the uniformity of particle size was low.

[0145] Sample Average particle size (SEM) standard deviation Colloidal silica with an average particle size of 40 nm 43.2 4.1 Example 1-1 55.6 3.7 Example 2-1 54.8 4.6 Example 3-1 55.6 5.3 Comparative Example 1 42.9 9.2 Comparative Example 2 56.5 12.3 Colloidal silice with an average particle size of 120 nm 124.5 7.1 Examples 1-2 141.0 8.4 Example 2-2 141.0 8.4 Example 3-2 146.1 7.6

[0147] Experimental Example 3. Experiment to Confirm Cerium Oxidation Status of Composite Particles via XPS

[0148] The cerium oxidation state of the nano-ceria particles and the composite particles prepared through Examples 1-2 above was confirmed by XPS analysis. (Analysis was performed using a Thermofisher K-ALPHA analyzer.) As shown in Fig. 7, the Ce of the composite particles prepared through the method of Example 1-2 3+ The ratio of Ce of existing nano-ceria particles 3+ Improved results compared to the ratio can be confirmed. Through this, a high Ce can be achieved using the ceria nanoparticle coating method on the core particle surface. 3+ It was confirmed that the surface characteristics of nano-ceria particles containing a ratio can be utilized.

[0150] Experimental Example 4. Polishing Evaluation Experiment of Composite Particles

[0151] The slurry containing the composite particles of the examples and comparative examples was polished under the following polishing conditions.

[0152] 1. Grinder: CTS AP300

[0153] 2. Pad: IC1010

[0154] 3. Polishing time: 15 sec

[0155] 4. Platen speed: 93 rpm

[0156] 5. Head speed: 87 rpm

[0157] 6. Flow rate (slurry flow rate): 250 ml / min

[0158] 7. Wafer used: 300 mm PETEOS wafer

[0159] 8. Pressure: 2.0 psi

[0161] Table 3 below shows the results regarding the slurry content, particle size (z-size), pH, and polishing rate of the examples and comparative examples. From Table 3, it can be seen that the polishing rates of Examples 1-1 to 1-2 are excellent, with an average polishing rate of the entire wafer of 1,000 Å or more, and in the case of Example 1-2, the average polishing rate of the entire wafer of 4,000 Å or more.

[0162] slurry Content pH Z-size(nm) Oxide Removal Rate ( / min) Example 1-1 (Colloidal silica core with average particle size of 40 nm) 0.25wt% 5.0 108.8 1,714 0.25wt% 8.8 144.1 1,109 Example 1-2 (Colloidal silica core with average particle size of 120 nm) 0.25wt% 4.0 183.6 4,514 0.25wt% 5.0 182.4 3,665 0.25wt% 6.0 196.4 3,703 Example 4 0.75wt% 3.5 128.4 764

Claims

Claim 1 A method for manufacturing a composite particle having a core coated with cerium oxide particles, wherein the method comprises: a) preparing a dispersion of core particles and a dispersion of cerium oxide particles having an average particle size of 3 to 7 nm; b) mixing the core particle dispersion and the cerium oxide particle dispersion to prepare an acidic mixed dispersion; and c) adding a pH adjuster to the mixed dispersion and stirring so that the pH becomes 5 to 10, wherein the cerium oxide particles are Ce 4+ and Ce 3+ Includes, and the above Ce 4+ and Ce 3+ A method for manufacturing composite particles in which the core is coated with cerium oxide particles, wherein the weight ratio of is 1:0.2 to 0.

8. Claim 2 A method for manufacturing a composite particle having a core coated with cerium oxide particles, wherein, in claim 1, the cerium oxide particles are manufactured by a method of the group consisting of a liquid phase method, a calcination method, and combinations thereof. Claim 3 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, steps a) to c) are performed at a temperature of 15 ℃ to 85 ℃. Claim 4 A method for manufacturing a composite particle having a core coated with cerium oxide particles, wherein, in claim 1, the pH adjuster is selected from the group consisting of ammonia water, imidazole, hexamethylenetetramine, aminobutyric acid, lysine, arginine, histidine, triethanolamine, diethanolamine, tetramethylammonium hydroxide, potassium hydroxide, sodium hydroxide, and combinations thereof. Claim 5 delete Claim 6 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the core particles are selected from the group consisting of silica (SiO2), alumina (Al2O3), ceria (CeO2), zirconia (ZrO2), titania (titanium oxide), zeolite, polystyrene, polymethacrylate, and combinations thereof. Claim 7 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, characterized in that, in claim 1, the core particles are colloidal silica. Claim 8 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the core particles have an average particle size of 20 nm to 150 nm. Claim 9 delete Claim 10 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the cerium oxide particles are mixed in an amount of 1 to 150 parts by weight relative to 100 parts by weight of the core particles. Claim 11 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, characterized in that, in claim 1, the stirring in step c) is performed for 1 to 12 hours. Claim 12 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the pH adjuster is added in an amount of 0.1 to 100 parts by weight relative to 100 parts by weight of the core particle. Claim 13 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the manufacturing method further comprises the step of centrifuging, washing, and dispersing after step c). Claim 14 delete Claim 15 A method for manufacturing a composite particle in which the core is coated with cerium oxide particles, wherein, in claim 1, the composite particle comprises 1 to 50 parts by weight of cerium oxide particles per 100 parts by weight of core particles. Claim 16 A method for manufacturing a composite particle with a core coated with cerium oxide particles according to claim 1, wherein the composite particle with a core coated with cerium oxide particles has a standard deviation according to particle size distribution of 20% or less of the diameter of the composite particle. Claim 17 delete Claim 18 A method for manufacturing a composite particle having a core coated with cerium oxide particles, wherein, in claim 1, the composite particle has a positive zeta potential of 10 mV to 50 mV. Claim 19 A method for manufacturing a chemical mechanical planarization composition comprising the step of manufacturing a composite particle according to the method for manufacturing a composite particle in which the core of claim 1 is coated with cerium oxide particles, and obtaining a composition containing the same. Claim 20 A method for manufacturing a chemical mechanical planarization composition according to claim 19, wherein the chemical mechanical planarization composition comprises 0.1% to 5% by weight of a composite particle in which the core is coated with cerium oxide particles. Claim 21 A method for preparing a chemical mechanical planarization composition according to claim 19, characterized in that the pH of the chemical mechanical planarization composition is in the range of 3 to 11.

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