Dispersion composition of cerium oxide composite powder

Abstract

The present invention relates to a cerium oxide composite powder and a dispersion composition containing the cerium oxide composite powder. The cerium oxide composite powder contains two or more cerium oxide particles whose particle sizes are different from each other and meet a specific combination range. By controlling the average density of the cerium oxide composite powder contained in the dispersion composition solution, when the cerium oxide composite powder is applied to the dispersion composition, a higher polishing rate can be achieved without causing damage to the substrate, and the cerium oxide composite powder also has the advantage of excellent storage stability.

Description

Technical Field

[0001] The present invention relates to a dispersion composition comprising a cerium oxide composite powder containing two types of cerium oxide particles having different particle sizes. Background Art

[0002] With the high integration of semiconductor elements, in order to ensure the photolithography margin and minimize the wiring length, the planarization technology of the lower film is required. The planarization methods of the lower film include borophosphorus silicate glass (BPSG) reflow, spin on glass (SOG) etchback and chemical mechanical polishing (hereinafter referred to as "CMP") engineering.

[0003] Among them, because the CMP process can achieve flattening and low-temperature flattening of a wider spatial area that cannot be achieved through the reflow process or the etch-back process, it is developing into the most popular flattening technology for the new generation of semiconductor components. However, while increasing the wiring thickness to reduce wiring resistance, the thickness of the metal insulating layer (InterMetal Dielectric layer, hereinafter referred to as "IMD") used to achieve electrical insulation between metals will also increase relatively, so the absolute removal amount used to achieve flattening in the CMP step will also increase significantly. In addition, because the removal speed of the existing CMP slurry is slow, the CMP time will also become very long, resulting in a problem of reduced process productivity.

[0004] In order to improve the above-mentioned problems, a surface-modified colloidal ceria abrasive particle dispersion composition in which cerium element and hydroxyl group (-OH) are coated on the surface of ceria abrasive particles can be considered. However, in the above-mentioned dispersion composition, since the surface of the larger ceria abrasive particles is coated with the smaller ceria abrasive particles with higher surface activity, the physical properties of the larger ceria surface particles cannot be fully presented, and thus the polishing rate cannot be fully improved.

[0005] In addition, it is possible to consider a dispersion composition that activates the chemical reaction and improves the grinding speed while reducing the grinding damage by using hydroxide particles of a tetravalent metal element and making special restrictions on the density of the particles. However, the crystallinity of the hydroxide particles as described above is crossed, so the physical properties cannot be fully presented, thereby the grinding speed cannot be fully improved.

[0006] In addition, a scheme of using first particles containing ceria oxide and second particles containing a hydroxide of a tetravalent metal element can be considered. However, in the above-mentioned hydroxide particles, mutual aggregation occurs between the particles, so there is a problem that an additive containing a special compound must be used, and because the dispersed particles of the dispersion composition are large, there is a problem that scratches may be formed during CMP polishing.

[0007] Prior art literature

[0008] Patent Literature

[0009] (Patent Document 1) Korean Patent Publication No. 10-2002-0007607 Summary of the invention

[0010] The present invention aims to solve the above-mentioned existing problems, and the purpose of the present invention is to maximize the physical effect (Mechanical effect) on the insulating film by making the shape of the first cerium oxide particles with larger particles into a sharp angle shape, and to maximize the chemical effect (Chemical effect) by increasing the specific surface area of ​​the second cerium oxide particles with smaller particles. As mentioned above, the purpose of the present invention is to provide a cerium oxide composite powder and a dispersion composition containing the cerium oxide composite powder, which achieves chemical and physical effects by mixing the first particles with stronger physical effects and the second particles with stronger chemical effects, and has excellent anti-agglomeration stability and very excellent polishing speed by adjusting the density range of the cerium oxide composite powder contained in the solution.

[0011] In order to solve the above-mentioned problems, the present inventors have developed a dispersion composition which has excellent dispersion stability and excellent particle crystallinity and which ensures excellent chemical and physical polishing properties by surface activation through continuous research.

[0012] The present invention is a dispersion composition in which first cerium oxide particles and second cerium oxide particles are composited, wherein the first cerium oxide particles are large particles having sharp angular shapes, excellent crystallinity, and a powder density of 6.5 g / mL or more, and the second cerium oxide particles are small particles having a spherical shape, excellent crystallinity, and a density of 2.5 g / mL or less, the surface of which is activated by hydrothermal synthesis. In addition, the present invention is characterized in that the first cerium oxide particles and the second cerium oxide particles do not exist in a core-shell form in a solution, but are independently dispersed and agglomerated.

[0013] Generally speaking, most of the volume of nano-sized particles is located on the surface. Therefore, in the present invention, the particles with excellent crystallinity are surface-modified by strong crushing and grinding processes, thereby controlling the density of the composite powder to be below 3.0 gg / mL, so that the core part of the particles has excellent crystallinity and the surface part contains a large number of hydroxyl groups. In this way, the grid-like connection can be concentrated in the core of the volume and most of the volume located on the surface is composed of hydroxyl groups, thereby having both mechanical grinding characteristics and chemical grinding characteristics and achieving a higher oxide film grinding rate.

[0014] In addition, although the density of the composite powder produced by the process in the present invention is relatively low at about 2.55 g / mL to 2.95 g / mL, it has excellent physical grinding properties and excellent grinding properties by chemical action, and has very excellent dispersion stability because there is less mutual agglomeration between particles. In particular, the larger particles with sharp edges play an important role in improving the physical grinding properties, and the smaller particles with spherical shapes have excellent crystallinity through hydrothermal synthesis, and contain a large number of hydroxyl groups on the surface through the process, so that they can show the improvement effect of the grinding action together with the larger particles.

[0015] More specifically, the present invention provides a cerium oxide composite powder, comprising: first cerium oxide particles, the average particle size of which is greater than 15 nm; and second cerium oxide particles, the average particle size of which is less than 10 nm. In this case, the mixing ratio of the first cerium oxide particles and the second cerium oxide particles can be 9.5:0.5 to 0.5:9.5 (wt. / wt.), specifically, 8:2 to 2:8 (wt. / wt.), and more specifically, 6:4 to 4:6 (wt. / wt.).

[0016] In addition, when the cerium oxide composite powder is analyzed by a transmission electron microscope (TEM), the cerium oxide composite powder may contain an average of 50 to 19,000 second cerium oxide particles per unit area (horizontally 550 nm and vertically 550 nm) per first cerium oxide particle. In addition, the cerium oxide composite powder may have an average BET specific surface area of ​​50.00 m2 / g or more.

[0017] At the same time, the particle size (D50) of the cerium oxide composite powder slurry is

[0018] 50 nm to 180 nm when analyzed using a Zetasizer;

[0019] 60 nm to 350 nm when analyzed using a laser particle size analyzer (Microtrac);

[0020] When analyzed using a Lumisizer, the diameter was 30 nm to 70 nm.

[0021] Furthermore, the present invention provides a dispersion composition comprising the cerium oxide composite powder as described above. Wherein, when the dispersion composition is dried at 60°C and vacuum conditions for 72 hours, the average density of the cerium oxide composite powder contained in the dispersion composition can be 2.55g / mL to 2.95g / mL. In addition, the average density of the composite powder contained in the dispersion composition solution can be 1.0g / mL to 2.95g / mL. In addition, the dispersion composition dispersed at a concentration of 0.007wt.% can have an absorbance of 0.02 to 0.19% at a wavelength of 450 to 600nm, and a transmittance of 70 to 90% at a wavelength of 500nm. In addition, the average particle size change when the dispersion composition is placed at 40°C for more than 30 days is within 5%.

[0022] The cerium oxide composite powder applicable to the present invention contains two types of cerium oxide particles with different particle sizes and satisfying a specific particle size range. In addition, by controlling the average density of the cerium oxide composite powder contained in the dispersed composition solution, when it is applied to the dispersed composition, a higher polishing rate can be achieved without causing damage to the substrate, and it also has the advantage of excellent storage stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 These are transmission electron microscope (TEM) analysis images of cerium oxide particles and cerium oxide composite powders obtained in Production Examples, Examples, and Comparative Examples.

[0024] Figure 2 This is a transmission electron microscope (TEM) analysis image illustrating the lattice spacing of the second cerium oxide particles obtained in Production Example 2.

[0025] Figure 3 This is an image obtained by analyzing the crystallinity of the cerium oxide composite powder of the example using an X-ray diffraction (XRD) analyzer.

[0026] Figure 4 This is a graph analyzing the density of the cerium oxide composite powder obtained in the example and the density of the cerium oxide composite powder contained in the solution.

[0027] Figure 5 This is a graph evaluating the polishing rates of the dispersed compositions obtained in Examples and Comparative Examples. DETAILED DESCRIPTION

[0028] Before describing the present invention in detail, it should be understood that the terms used in this specification are only used to describe specific embodiments and are not intended to limit the scope of the present invention, which should only be defined according to the scope of the claims. Unless otherwise mentioned, the meanings of all technical terms and scientific terms used in this specification are the same as those commonly understood by people with general technical skills.

[0029] Throughout this specification and claims, unless otherwise mentioned, the terms comprise, comprise, and comprising merely mean the inclusion of the mentioned items, steps, or a series of items and steps, and do not mean the exclusion of any other items, steps, or a series of steps.

[0030] In addition, "A to B" used to indicate a range in the present specification means a range of not less than A and not more than B.

[0031] Next, the present invention will be described in more detail.

[0032] In one embodiment of the present invention, a cerium oxide composite powder is provided, comprising: first cerium oxide particles, the average particle size of which is greater than 15 nm; and second cerium oxide particles, the average particle size of which is less than 10 nm. In the composite powder, the two types of particles can exist independently or in contact with each other, and maintain independent agglomeration forms. At this time, in order to maintain the physical grinding properties of the first cerium oxide particles, the composite powder does not exist in a core-shell form with the second cerium oxide particles covering the surface.

[0033] The cerium oxide composite powder applicable to the present invention comprises two cerium oxide particles with different average particle sizes, and the two cerium oxide particles have different specific particle size ranges. Specifically, the cerium oxide composite powder comprises a first cerium oxide particle with a larger average particle size of 15 nm or more and a second cerium oxide particle with a smaller average particle size of 10 nm or less, and more specifically, comprises a first cerium oxide particle with an average particle size of 15 to 60 nm; 20 to 55 nm; 25 to 50 nm; 30 to 45 nm; or a first cerium oxide particle with an average particle size of 20 nm or more but less than 40 nm and a second cerium oxide particle with an average particle size of 1 to 10 nm; 1 to 6 nm; 2 to 5 nm; or a second cerium oxide particle with an average particle size of 1 nm or more but less than 3 nm.

[0034] The shape of the first cerium oxide particles with a larger average particle size may be a pointed shape, but is not limited thereto. Thereby, the grinding speed can be made even better. In addition, the cerium oxide composite powder may include the first cerium oxide particles and the second cerium oxide particles in a weight ratio (wt. / wt.) of 9.5:0.5 to 0.5:9.5, specifically, it may include a weight ratio (wt. / wt.) of 8:2 to 2:8, more specifically, it may include a weight ratio (wt. / wt.) of 6:4 to 4:6, and in some cases, it may include a ratio (wt. / wt.) of 5.5:4.5 to 4.5:5.5.

[0035] Thus, when the cerium oxide composite powder is analyzed by a transmission electron microscope (TEM), the cerium oxide composite powder may contain 50 to 19,000 second cerium oxide particles per unit area (550 nm horizontally and 550 nm vertically) relative to one first cerium oxide particle. For example, when the cerium oxide composite powder is analyzed by a transmission electron microscope (TEM), the cerium oxide composite powder may contain 400 to 2500 or 650 to 1500 second cerium oxide particles per unit area (550 nm horizontally and 550 nm vertically) relative to one first cerium oxide particle.

[0036] Furthermore, the cerium oxide composite powder may include two types of cerium oxide particles having average particle sizes different from each other in the above ratio, and may exhibit a particle size value within a specific range according to a measurement method.

[0037] As an example, the dispersed particle size of the cerium oxide composite powder can be 50nm to 180nm when analyzed using a zeta potential analyzer (Zetasizer); can be 60nm to 350nm when analyzed using a laser particle size analyzer (Microtrac); can be 30nm to 70nm when analyzed using a stability analyzer (Lumisizer).

[0038] Specifically, the dispersed particle size of the cerium oxide composite powder is

[0039] When analyzed by a zeta potential meter (Zetasizer), the range may be 70 nm to 150 nm; or 100 nm to 110 nm;

[0040] When analyzed by a laser particle size analyzer (Microtrac), it can meet 120nm to 200nm; or 170nm to 185nm;

[0041] When analyzed using a luminometer, the range may be 30 nm to 50 nm; or 35 nm to 45 nm.

[0042] The particle size is the force equivalent to 50% of all particles (D50), and the particle size value when analyzed by a zeta potential meter (Zetasizer) and a laser particle size analyzer (Microtrac) is the volume average diameter (DV(50)) value.

[0043] The larger the size of the cerium oxide particles contained in the cerium oxide composite powder, the better the polishing speed can be achieved when used as an abrasive, but the chemical activity of the abrasive decreases due to the lower specific surface area, and the surface of the polished substrate is damaged. On the contrary, when the size of the cerium oxide particles is small, the chemical activity of the abrasive can be improved while preventing the surface of the polished substrate from being damaged, but the polishing speed is significantly reduced.

[0044] However, the cerium oxide composite powder of the present invention comprises two types of cerium oxide particles having different particle sizes, and the average particle size of the cerium oxide particles and the dispersed particle size (D50) range of the cerium oxide composite powder obtained by mixing the particles are adjusted to the range described above. Therefore, it is possible to prevent the surface of the polished substrate from being damaged and to significantly increase the polishing speed by maximizing the chemical and physical activity of the abrasive. It also has the advantage of excellent storage stability of the abrasive.

[0045] In addition, the average BET specific surface area of ​​the cerium oxide composite powder may be 50.00 m2 / g or more. For example, the average BET specific surface area of ​​the cerium oxide composite powder may be 70.00 m2 / g to 250 m2 / g; 70.00 m2 / g to 150 m2 / g; 70.00 m2 / g to 90 m2 / g; 120.00 m2 / g to 200 m2 / g; 150.00 m2 / g to 250 m2 / g; 110.00 m2 / g to 160 m2 / g; 130.00 m2 / g to 150 m2 / g; 180.00 m2 / g to 240 m2 / g.

[0046] The present invention controls the average BET specific surface area of ​​the cerium oxide composite powder within the above range, thereby maximizing the contact area between the dispersed composition containing the composite powder and the substrate surface during polishing, thereby performing chemical polishing while preventing damage to the substrate surface.

[0047] Furthermore, the present invention provides a dispersion composition comprising the above-mentioned cerium oxide composite powder.

[0048] The dispersion composition applicable to the present invention contains a cerium oxide composite powder having two cerium oxide particles with different particle sizes and satisfying a specific combination range, so that a high polishing rate can be achieved without damaging the substrate during use, and storage stability can also be improved.

[0049] Wherein, when the dispersion composition is dried at 60°C and vacuum conditions for 72 hours, the average density of the cerium oxide composite powder contained in the dispersion composition may be 2.55 g / mL to 2.95 g / mL. In addition, the average density of the composite powder contained in the dispersion composition solution may be 1.0 g / mL to 2.95 g / mL. At this time, when the dispersion composition is dried at 60°C and vacuum conditions for 72 hours, the average density of the cerium oxide composite powder contained in the dispersion composition may be 2.55 g / mL to 2.95 g / mL, specifically, 2.70 g / mL to 2.85 g / mL. As an example, the average particle size of the cerium oxide composite powder contained in the dispersion composition may be 2.81 ± 0.05 g / mL.

[0050] In addition, when the dispersion composition is dried for 2 hours, the average density of the cerium oxide composite powder contained in the solution of the dispersion composition can be 1.0 g / mL to 2.8 g / mL, specifically, 1.6 g / mL to 1.8 g / mL. As an example, the average particle size of the cerium oxide composite powder contained in the solution of the dispersion composition can be 1.69±0.05 g / mL. The present invention can improve the problem that the effect of the particles on the polished film is weakened and the polishing speed is further reduced due to the low density of the cerium oxide composite powder, and at the same time, it can prevent the problem that the surface of the substrate is damaged due to the high density of the cerium oxide composite powder.

[0051] At the same time, the dispersion composition of the present invention has an average particle size change of less than 5% when stored at 40°C for more than 30 days and has excellent storage stability. Therefore, the grinding characteristics of the dispersion composition can be stably achieved even after a long period of time.

[0052] Furthermore, the dispersion composition may use water as a solvent or may be mixed with a portion of an organic solvent. In this case, the dispersion composition may be prepared by dispersing and / or mixing the cerium oxide composite powder of the present invention in a solvent at 0.3 to 15 wt.%.

[0053] In addition, the dispersion composition may further include various additives in addition to the cerium oxide composite powder, such as a dispersant, a defect inhibitor, an oxidant, a grinding accelerator, and a pH adjuster, for example.

[0054] The dispersant may include at least one selected from the group consisting of nitric acid, formic acid, acetic acid, benzoic acid, oxalic acid, succinic acid, malic acid, maleic acid, malonic acid, citric acid, lactic acid, aspartic acid, glutaric acid, adipic acid, and salts thereof.

[0055] In addition, the manufacturing method of the cerium oxide composite powder and the dispersion composition applicable to the present invention can be applied to the manufacturing method commonly used in the relevant industry, and is not subject to special restrictions. For example, the cerium oxide composite powder can be used as a wet oxidation method, a sol-gel method, a hydrothermal synthesis method, and a roasting method. As an example, the cerium oxide composite powder can be obtained by oxidizing the cerium precursor by mixing the cerium precursor with an alkaline substance and thereby obtaining cerium oxide, then washing, drying, and crushing it, and then diluting it with water to obtain a dispersion composition containing the cerium oxide composite powder. In order to obtain the cerium oxide composite powder of the present invention, specific examples are given by embodiments. The cerium precursor is not subject to special restrictions, and preferably can be in the form of a salt. As a non-limiting example, cerium nitrate, cerium acetate, cerium chloride, cerium carbonate, cerium ammonium nitrate, and the hydrate thereof can be used as examples, and can be used alone or in combination with more than two.

[0056] Next, the present invention will be described in more detail through examples. The following description is only a specific example of the present invention, and even if it includes definitive and restrictive expressions, it does not limit the scope of the claims defined in the claims.

[0057] <Manufacturing Example 1> Manufacturing of First Cerium Oxide Particles

[0058] A precursor solution was prepared by dissolving 1.85 kg of cerium carbonate hydrate (Ce2(CO3)3)·xH2O) in 18.15 kg of water and 2.4 kg of nitric acid (HNO3) and stirring for 1 hour. 6 kg of ammonia water was added to the precursor solution, and after the addition, the temperature was raised to 75°C and the reaction was carried out for 6 hours while stirring. The first cerium oxide particles were prepared by filtering the obtained precipitate with a filter press, washing it and heat treating it at 1000°C, and the density of the particles was 6.5 g / mL or more.

[0059] <Manufacturing Example 2> Manufacture of Second Cerium Oxide Particles

[0060] After 1.2 kg of ammonium cerium nitrate ((NH4)2Ce(NO3)6) was dissolved in 2 kg of water, 10 g of hydrogen peroxide (H2O2) was added and stirred for 1 hour to produce a precursor solution. 2 kg of ammonia water was added to the precursor solution, and the reaction solution was subjected to a hydrothermal synthesis reaction at 200°C. The obtained precipitate was filtered and washed by a filter press and vacuum dried at 60°C to produce the second cerium oxide particles, at which the particle density was less than 2.5 g / mL.

[0061] <Comparative Production Example 1> Production of Cerium Hydroxide Particles

[0062] A precursor solution was prepared by dissolving 350 g of ammonium cerium nitrate ((NH4)2Ce(NO3)6) in 7825 g of water and stirring. 750 g of imidazole was added to the precursor solution at a rate of 5 mL / min to obtain a precipitate containing cerium hydroxide. The obtained precipitate was filtered and washed using a filter press to obtain cerium hydroxide particles.

[0063] <Examples 1 to 7 and Comparative Examples 1 to 2>

[0064] The first cerium oxide particles obtained in Preparation Example 1 and the second cerium oxide particles obtained in Preparation Example 2 were mixed as shown in Table 1 and then pulverized and wet-milled. The milled dispersion composition was vacuum-dried at 60° C. to finally produce a cerium oxide composite powder.

[0065]

Table 1

[0066]

[0067] a: Comparative Example 3 is a mixed particle in which the first cerium oxide particles of Production Example 1 and the cerium hydroxide particles of Comparative Production Example 1 were mixed but the mixed particles were not wet-milled.

[0068] <Examples 8 to 14 and Comparative Examples 4 to 6>

[0069] As shown in Table 2 below, each of the cerium oxide composite powders obtained in Examples 1 to 7 and Comparative Examples 1 to 3 was mixed with water at 1.0 wt % and then dispersed to prepare a dispersion composition.

[0070]

Table 2

[0071]

[0072] <Test Example 1> Evaluation of cerium oxide composite powder

[0073] In order to evaluate the morphology and particle size of the first and second cerium oxide particles used in the present invention and the dispersed particle size and BET specific surface area of ​​the cerium oxide composite powder containing the cerium oxide particles, the following test was performed on the first and second cerium oxide particles obtained by Preparation Examples 1 to 2; and the cerium oxide composite powders obtained by Examples 1 to 7 and Comparative Examples 1 to 3.

[0074] A) Particle size and morphology analysis of the first and second cerium oxide particles

[0075] The cerium oxide particles and cerium oxide composite powders obtained in the preparation examples, embodiments and comparative examples were analyzed by transmission electron microscopy (TEM). Figure 1 shown.

[0076] See also Figure 1 It can be confirmed that the cerium oxide composite powder of the embodiment has a mixed morphology of the first cerium oxide particles with an average particle size of 20 to 50 nm in polygonal form and the second cerium oxide particles with an average particle size of 1 to 5 nm in spherical form. In addition, the crystallinity of the cerium oxide particles was confirmed by an X-ray diffraction (XRD) analyzer, and the results are as follows: Figure 3 In addition, the results of Production Example 2 confirmed that the second cerium oxide particles had an average grid spacing of 0.31±0.005 nm, and that the cerium oxide composite powders obtained in Examples 1 to 7 contained 50 to 19,000 second cerium oxide particles per first cerium oxide particle.

[0077] The above results indicate that the cerium oxide composite powder applicable to the present invention contains only oxidized cerium particles, and the cerium oxide particles have a structure in which two types of particles having different sizes are mixed and / or dispersed in a certain ratio.

[0078] B) Particle size analysis of cerium oxide composite powder

[0079] The cerium oxide particles and cerium oxide composite powders obtained by the manufacturing examples, embodiments and comparative examples were subjected to ① Zeta potential analysis; ② Microtrac analysis; and ③ Lumisizer analysis, thereby measuring the 50% particle size (D50) of each cerium oxide particle and cerium oxide composite powder. The measured results are shown in Table 3 below.

[0080]

Table 3

[0081]

[0082] Referring to Table 3, it can be seen that the cerium oxide composite powder applicable to the present invention comprises two types of cerium oxide particles with different particle sizes, and has a certain particle size range according to different measurement methods.

[0083] C) BET specific surface area analysis of cerium oxide composite powder

[0084] The BET specific surface areas of the cerium oxide particles and cerium oxide composite powders obtained in the Production Examples, Examples, and Comparative Examples were measured.

[0085] As a result, it can be confirmed that the average BET specific surface areas of the first cerium oxide particles and the second cerium oxide particles obtained by Preparation Examples 1 and 2 are 22.76 m2 / g and 183.50 m2 / g, respectively, and the average BET specific surface areas of the cerium oxide composite powders obtained by Examples 1, 4 and 7 are 73.80 m2 / g, 142.62 m2 / g and 178.57 m2 / g, respectively.

[0086] <Test Example 2> Evaluation of Dispersion Composition

[0087] In order to evaluate the optical properties, storage stability, polishing efficiency, etc. of the dispersion composition to which the present invention is applied, the following test was performed on the dispersion compositions obtained in Examples 8 to 14 and Comparative Examples 4 to 6.

[0088] A) Evaluation of optical properties of dispersion composition

[0089] The dispersion composition obtained in Example 12 (first cerium oxide particles: second cerium oxide particles = 50:50 wt.% / wt.%) was dispersed in distilled water at a concentration of 0.007 wt.% to prepare a slurry, and about 4 mL of the prepared slurry was put into a 1 cm×1 cm cell, and the cell was placed in a spectrophotometer. Next, the absorbance at a wavelength of 450 nm and the transmittance at a wavelength of 500 nm were measured.

[0090] As a result, it was confirmed that when the dispersion composition was dispersed at 0.007 wt.%, the absorbance in the wavelength range of 450 to 600 nm was 0.027 ± 0.005%, which was within the range of 0.02 to 0.19%. In addition, it was confirmed that when the dispersion composition was dispersed at 0.007 wt.%, the transmittance at a wavelength of 500 nm was 85.35 ± 0.005%, which was within the range of 70 to 90%.

[0091] B) Evaluation of the density of cerium oxide particles in the dispersed composition

[0092] The cerium oxide particles obtained in Preparation Example 1, Preparation Example 2, and Comparative Preparation Example were mixed into a dispersion composition as shown in Table 4 below, and then pulverized and wet-milled to prepare a dispersion composition sample. The dispersion composition was then dried at 60° C. under vacuum conditions for 72 hours, and the density of the composite powder was measured. In addition, the composite powder was dispersed in distilled water at a concentration of 5.0 wt.%, and the density of the composite powder contained in the dispersion composition solution was measured.

[0093] At this time, the measurement conditions are as follows, and the results are shown in Table 4 and Figure 4 As shown. In addition, in Comparative Example 3, the particles obtained by Manufacturing Example 1 and Comparative Manufacturing Example 1 were mixed into a dispersed composition (first cerium oxide particles: second cerium hydroxide particles = 50:50 wt.% / wt.%) and then irradiated with ultrasound to prepare a dispersed composition sample, and then the dispersed composition was dried at 60°C and vacuum conditions for 72 hours, and the density of the composite powder was measured. In addition, after the composite powder was dispersed in distilled water at a concentration of 5.0 wt.%, the density of the composite powder contained in the solution of the dispersed composition was measured:

[0094] (Condition ①) After the pulverized and wet-milled dispersion composition was dried at 60° C. under vacuum conditions for 72 hours, the density was calculated using the following formula 1 using a 50 mL pycnometer.

[0095] (Condition ②) After the mixed dispersion composition was dried at 60°C and vacuum conditions for 72 hours, the density was calculated using a 50 mL pycnometer using the following formula 1:

[0096] [Formula 1] PD=PW / PV, PV=CV-WV, WV=WW / WD

[0097] (PD: powder density, PW: powder weight, PV: powder volume, CV: pycnometer volume, WV: water volume, WW: water weight, WD: water density)

[0098] (Condition ③) After the mixed powder produced by conditions ① and ② was dispersed in distilled water at a concentration of 5.0 wt.%, the density of the composite powder contained in the solution was calculated by the following formula 2:

[0099] [Formula 2] PD=PW / PV, PV=SV-WV, WV=WW / WD, WW=SW-PW

[0100] (PD: powder density in solution, PW: powder weight, PV: powder volume, SV: slurry volume, WV: water volume, WW: water weight, WD: water density, SW: slurry weight)

[0101]

Table 4

[0102]

[0103] See Table 4 and Figure 4 It can be seen that the dispersion composition applicable to the present invention has a specific density range of the cerium oxide composite powder.

[0104] C) Evaluation of storage stability of dispersion composition

[0105] A sample was prepared by dispersing the cerium oxide composite powder obtained by manufacturing examples 1 and 2 in distilled water at a concentration of 5.0 wt%. Next, the dispersed particle size of the cerium oxide composite powder contained in the prepared sample and the dispersion composition manufactured by Examples 8, 11 and 14 and Comparative Example 5 was measured, and placed in a constant temperature bath at 40°C for more than 30 days. After more than 30 days, the average particle size of each sample and the dispersion composition was measured again to confirm the change in particle size. The results are shown in Table 5 below.

[0106]

Table 5

[0107]

[0108] The dispersion composition to which the present invention is applied does not significantly change the dispersed particle size of the cerium oxide composite powder after long-term storage, and thus the grinding characteristics of the composition can be stably achieved without change even after a long period of time.

[0109] D) Evaluation of the grinding efficiency of the dispersion composition

[0110] First, a sample was prepared by dispersing the cerium oxide particles obtained in Preparation Examples 1 and 2 in distilled water at a concentration of 1.0 wt.%. The polishing rate of each of the prepared samples and the dispersion compositions obtained in Examples 8 to 14 and Comparative Examples 3 to 5 was measured by performing a test under the following conditions. The results are shown in FIG. Figure 5 shown.

[0111] - Polishing test: CMP device (model: DOOSAN UNIPLA 231)

[0112] -Board: IC1000TM A2 PAD 20'*1.18'ACAO:1Y10

[0113] - Duration: 60 seconds

[0114] -Spindle speed: 85rpm

[0115] - Wafer pressure: 5psi

[0116] -Slurry flow rate: 200cc / min

[0117] -Wafer: 8 inches (PETEOS)

[0118] -Wafer thickness:

[0119] See also Figure 5 The dispersed composition applicable to the present invention contains first cerium oxide particles and ground cerium oxide particles of specific sizes in a certain content ratio, so that grinding can be performed without damaging the surface of the polished substrate; and it has a relatively high polishing speed compared to a composition that only contains first cerium oxide particles with larger particles or second cerium oxide particles with smaller particles.

[0120] Specifically, it was confirmed that the dispersion composition of the example did not damage the polished substrate surface, but the substrate surface was damaged in Production Example 1 or Comparative Example 3 containing the first cerium oxide particles alone or at a high content.

[0121] In addition, it can be confirmed that the dispersion compositions of the examples all exhibited approximately The above high polishing speed, especially in the dispersion compositions of Examples 10 to 12 in which the mixing ratio of the first cerium oxide particles to the second cerium oxide particles is 6:4 to 4:6 (wt. / wt.), the polishing speed is significantly increased to In contrast, in the samples containing the first cerium oxide particles or the second cerium oxide alone (Manufacturing Examples 1 and 2) and the dispersion compositions containing the cerium oxide particles in different mixing ratios from the present invention (Comparative Examples 3 and 4), insufficient Lower grinding speed.

[0122] The above results confirm that the dispersion composition applicable to the present invention includes a cerium oxide composite powder containing two types of cerium oxide particles having certain sizes at a specific ratio, and can achieve high polishing efficiency without damaging the substrate during use.

Claims

1. A dispersion composition of cerium oxide composite powder for CMP, As comprising: first cerium oxide particles having an average particle size of 20 nm or more and less than 40 nm; and The second cerium oxide particles have an average particle size of 1 nm to 6 nm; the first cerium oxide particles and the second cerium oxide particles are mixed in a weight ratio of 6:4 to 4:6, and The first cerium oxide particles have a pointed shape, and the second cerium oxide particles have a spherical shape and the surface of the particles is activated by hydrothermal synthesis.

2. The dispersion composition of the cerium oxide composite powder for CMP according to claim 1, When the cerium oxide composite powder is analyzed using a transmission electron microscope TEM, the cerium oxide composite powder contains an average of 50 to 19,000 second cerium oxide particles per first cerium oxide particle in a unit area of ​​550 nm horizontally and 550 nm vertically.

3. The dispersion composition of cerium oxide composite powder for CMP according to claim 1, characterized in that: The average BET specific surface area of ​​the cerium oxide composite powder is 50.00 m2 / g or more.

4. The dispersion composition of cerium oxide composite powder for CMP according to claim 1, characterized in that: Dispersion density D 50 of cerium oxide composite powder, When analyzed using a zeta potential meter, the range is 50 nm to 180 nm; or 60 nm to 350 nm when analyzed using a laser particle size analyzer Micro trac; Alternatively, when analyzed using a stability measuring instrument, LumiSizer, the range is 30 nm to 70 nm.

5. The dispersion composition of cerium oxide composite powder for CMP according to claim 1, characterized in that: The average density of the cerium oxide composite powder contained in the solution of the dispersion composition is 1.0 g / mL to 2.95 g / mL.

6. The dispersion composition of cerium oxide composite powder for CMP according to claim 1, characterized in that: In the cerium oxide composite powder dispersion composition, after the concentration of the cerium oxide composite powder is adjusted to 0.007 wt.%, the absorbance at a wavelength of 450 to 600 nm is 0.02 to 0.19%, or the transmittance at a wavelength of 500 nm is 70 to 90%.

7. The dispersion composition of cerium oxide composite powder for CMP according to claim 1, The average particle size change after being left at 40°C for 30 days was 5% or less.

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