Cerium oxide particles, slurry composition for chemical mechanical polishing containing the same, and method for manufacturing semiconductor device

Abstract

Provided is a ceria particle for chemical mechanical polishing, and a slurry composition for chemical mechanical polishing containing the same. The surface of the ceria particle contains Ce 3+ and Ce 4+ When the ceria particle of the embodiment of the present application is used, by increasing the proportion of Ce 3+ on the surface of ceria, a high oxide film removal rate and an oxide film polishing selectivity ratio can be exhibited in a low content range, despite a small particle size.

Description

TECHNICAL FIELD

[0001] The present application relates to a ceria particle for chemical mechanical polishing, a slurry composition for chemical mechanical polishing comprising the same, and a method of manufacturing a semiconductor device, and more particularly, to a slurry composition for chemical mechanical polishing, which has a higher oxide film removal rate at a low content despite a small particle diameter, by increasing the proportion of Ce 3+ on the surface of ceria through synthesis, and a method of manufacturing a semiconductor device using the same. BACKGROUND

[0002] As semiconductor devices become diversified and highly integrated, more refined patterning techniques are being used, and thus, the surface structure of semiconductor devices is becoming more complex, and in order to improve the accuracy of photolithography, interlayer flatness plays an important role as a very important element in each process. In the manufacturing of semiconductor devices, a mechanical chemical polishing (CMP) process is used as such a planarization technique. For example, it is also more frequently used as a process for removing an insulating film that is excessively formed for interlayer insulation, a planarization process of an insulating film for a shallow trench isolation (STI) between an interlayer dielectric (ILD) and a chip, and a process for forming a metal conductive film such as a wiring, a contact slot, a via contact, etc.

[0003] For the CMP process, the polishing speed, the degree of planarization of the polished surface, and the degree of scratch generation are important, and are determined by the CMP process conditions, the type of slurry, the type of polishing pad, etc. A ceria slurry uses a high-purity ceria particle. Recently, in the manufacturing process of semiconductor devices, it is required to achieve further refined wiring, but the generation of polishing scratches during polishing is a problem that needs to be overcome.

[0004] The existing ceria slurry uses a particle having a particle diameter of 30 nm to 200 nm, and even if a slight polishing scratch is generated during polishing, it is not a problem as long as it is smaller than the existing wiring width, but in the current situation where highly refined wiring needs to be continuously achieved, it becomes a problem. In order to solve this problem, attempts are being made to reduce the average particle diameter of ceria particles, but the existing particles have a problem in that the polishing speed is reduced due to mechanical action when the average particle diameter is reduced.

[0005] Even if the polishing speed and the polishing scratch are controlled by controlling the average particle diameter of ceria particles as such, it is difficult to achieve the target level of the polishing scratch while maintaining the polishing speed.

[0006] In addition, in the existing slurry composition for chemical mechanical polishing, the ceria particles are not optimized in the proportion of Ce 3+ to Ce 4+ , and the optimal level of average particle diameter is not disclosed, and thus, there is a need for research on a polishing slurry including ceria particles that can exhibit a high oxide film removal rate despite a small particle diameter by increasing the proportion of Ce 3+ to Ce SUMMARY

[0007] TECHNICAL PROBLEM

[0008] An embodiment of the present application provides ceria particles for chemical mechanical polishing.

[0009] In addition, another embodiment of the present application provides a slurry composition for chemical mechanical polishing.

[0010] In addition, another embodiment of the present application provides a method of manufacturing a semiconductor device including the step of polishing using the slurry composition for chemical mechanical polishing.

[0011] In addition, another embodiment of the present application provides a semiconductor device.

[0012] In addition, another embodiment of the present application provides a method of manufacturing ceria particles for chemical mechanical polishing.

[0013] However, the technical problems of the present application are not limited to the above-described technical problems, and other various technical problems not mentioned can be clearly understood by those skilled in the art from the following description.

[0014] TECHNICAL SOLUTION

[0015] As a technical solution for solving the above-described technical problems, an embodiment of the present application provides ceria particles for chemical mechanical polishing, the transmittance of which is 50% or more for light having a wavelength of 500 nm in a water dispersion liquid in which the content of the ceria particles is adjusted to 1.0% by weight.

[0016] The average transmittance of the ceria particles for light having a wavelength of 450 to 800 nm is 50% or more in a water dispersion liquid in which the content of the ceria particles is adjusted to 1.0% by weight.

[0017] When the ceria particles are included in a slurry for chemical mechanical polishing, the slurry for chemical mechanical polishing can be transparent.

[0018] When the ceria particles are included in a slurry for chemical mechanical polishing, the ceria particles can be monodispersed.

[0019] The secondary particle diameter of the cerium oxide particles is 1 to 30 nm as measured by a dynamic light scattering (DLS) particle size analyzer.

[0020] The secondary particle diameter of the cerium oxide particles is 1 to 20 nm as measured by a dynamic light scattering (DLS) particle size analyzer.

[0021] The primary particle diameter of the cerium oxide particles is 0.5 to 15 nm when analyzed by X-ray diffraction (XRD).

[0022] The particle diameter of the cerium oxide particles is 10 nm or less when analyzed by transmission electron microscopy (TEM).

[0023] The particle diameter of the cerium oxide particles is 0.5 to 15 nm when analyzed by small / wide angle X-ray scattering (SAXS).

[0024] In a spectrum measured by Fourier-transform infrared (FT-IR) spectroscopy, the infrared transmittance is 90% or more in the range of 3000 cm -1 to 3600 cm -1 and is 96% or less in the range of 720 cm -1 to 770 cm -1 .

[0025] When X-ray photoelectron spectroscopy (XPS) analysis is performed on the surface of the cerium oxide particles, an XPS peak representing Ce-O binding energy of Ce 3+ may include a first peak of 900.2 to 902.2 eV, a second peak of 896.4 to 898.4 eV, a third peak of 885.3 to 887.3 eV, and a fourth peak of 880.1 to 882.1 eV.

[0026] When X-ray photoelectron spectroscopy (XPS) analysis is performed, the ratio of the sum of XPS peak areas representing Ce-O binding energy of Ce 3+ to the total sum of XPS peak areas representing Ce-O binding energy of the surface of the cerium oxide particles is 0.29 to 0.70.

[0027] has a first Raman peak in the band range of 455 cm -1 to 460 cm -1 .

[0028] In the spectral band range of 586 cm -1 ~ 627 cm -1 , a second Raman peak is also present.

[0029] In the spectral band range of 712 cm -1 ~ 772 cm -1 , a third Raman peak is also present.

[0030] The ratio A / B of the intensity A of the first Raman peak to the intensity B of the second Raman peak is 25 or less.

[0031] The ratio A / C of the intensity A of the first Raman peak to the intensity C of the third Raman peak is 50 or less.

[0032] Electron Energy Loss Spectroscopy (EELS) includes a first peak of 876.5 ~ 886.5 eV and a second peak of 894.5 ~ 904.5 eV, and the maximum intensity of the first peak can be greater than the maximum intensity of the second peak.

[0033] Further including a third peak of 886.5 ~ 889.5 eV and a fourth peak of 904.5 ~ 908.5 eV, the ratio (P1+P2) / P of the sum P1 of the areas of the third peak interval to the sum P2 of the areas of the fourth peak interval with respect to the total sum P of the peaks of the spectrum is 0.1 or less. t t

[0034] The area A3 of the peak representing Ce 3+ in the X-ray absorption fine structure (XAFS) spectrum is 0.03 or more with respect to the ratio A3 / (A3+A4) of the sum of the area A3 of the peak representing Ce 3+ to the area A4 of the peak representing Ce 4+ .

[0035] The area A3 of the peak representing Ce 3+ in the X-ray absorption fine structure (XAFS) spectrum is 0.1 or more with respect to the ratio A3 / (A3+A4) of the sum of the area A3 of the peak representing Ce 3+ to the area A4 of the peak representing Ce 4+ .

[0036] When measured by the XAFS spectrum, in the range greater than 5730 eV and less than 5740 eV, a first peak having a maximum absorbance coefficient of 0.1 ~ 0.4 is present. ​​

[0037] In the range of greater than 5740 eV and less than 5760 eV in the XAFS spectrum measurement, the second peak of the maximum absorption coefficient can be less than 0.6.

[0038] In the ultraviolet photoelectron spectroscopy (UPS) analysis, the maximum value of the number of photoelectrons released per second (Counts) of the cerium oxide particles can exist in the range of kinetic energy of 10 eV or less.

[0039] In the ultraviolet photoelectron spectroscopy (UPS) analysis, the maximum value of the number of photoelectrons released per second (Counts) of the cerium oxide particles can exist in the range of kinetic energy of 3 to 10 eV.

[0040] In the ultraviolet photoelectron spectroscopy (UPS) analysis, the work function value of the cerium oxide particles is 3.0 eV to 10.0 eV.

[0041] The BET specific surface area value of the cerium oxide particles is 50 m 2 / g or less.

[0042] The apparent density of the cerium oxide particles measured based on the static method is 2.00 to 5.00 g / mL.

[0043] The apparent density of the cerium oxide particles measured based on the tap method is 2.90 to 5.00 g / mL.

[0044] For the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when the photoluminescence (PL) intensity is measured at a wavelength of 325 nm, the maximum intensity of the first peak λ1 at a wavelength of 435 to 465 nm is in the range of 0.1 to 30.

[0045] The maximum intensity of the second peak λ2 at a wavelength of 510 to 540 nm is in the range of 0.1 to 10.

[0046] The intensity ratio λ1 / λ2 of the first peak λ1 to the second peak λ2 at a wavelength of 510 to 540 nm is 5 to 15.

[0047] When the color of the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight is expressed using the L*a*b* color system, the L* value is 95 or more, and the b* value is 10 to 25.

[0048] wherein L* represents luminance, a* represents redness, and b* represents yellowness.

[0049] The a* is -12 to -3.

[0050] When a water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight is subjected to centrifugal separation at a centrifugal force of 4250G for 30 minutes, the sedimentation rate of the cerium oxide particles is 25% by weight or less.

[0051] Further, another embodiment of the present application provides a slurry composition for chemical mechanical polishing, which contains cerium oxide particles and a solvent, wherein, in a water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, the light transmittance for light having a wavelength of 500 nm is 50% or more.

[0052] The content of the cerium oxide particles is 0.01 to 5 parts by weight, based on 100 parts by weight of the total weight of the slurry composition for chemical mechanical polishing.

[0053] The pH of the slurry composition for chemical mechanical polishing can be 2 to 10.

[0054] The slurry composition for chemical mechanical polishing is one or more inorganic acids selected from sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid, one or more organic acids selected from acetic acid, citric acid, glutaric acid, glycolic acid, formic acid, lactic acid, malic acid, dauric acid, maleic acid, oxalic acid, phthalic acid, succinic acid, and tartaric acid, one or more amino acids selected from lysine, glycine, alanine, arginine, valine, leucine, isoleucine, methionine, cysteine, proline, histidine, phenylalanine, serine, tris(hydroxymethyl)methylglycine, tyrosine, aspartic acid, tryptophan, and asparagine, imidazole, alkylamines, alcoholamines, quaternary ammonium bases, ammonia, or a combination thereof.

[0055] The solvent is deionized water.

[0056] The slurry composition for chemical mechanical polishing has a polishing rate of a silicon oxide film of

[0057] Another embodiment of the present application provides a slurry composition for chemical mechanical polishing, which contains cerium oxide particles and a solvent, wherein the cerium oxide particles are produced by a wet method, and the content of a precursor substance contained in the slurry composition is 300 ppm or less, based on weight.

[0058] The content of the cerium oxide particles is 0.001 to 5% or less, based on the total weight of the slurry composition for chemical mechanical polishing.

[0059] Another embodiment of the present application provides a slurry composition for chemical mechanical polishing, which contains cerium oxide particles, a solvent, and a cationic polymer.

[0060] ​The polishing rate of the oxide film can be increased depending on the content of the cationic polymer.

[0061] The cationic polymer can improve the polishing selectivity of the oxide film / polysilicon film.

[0062] The content of the cationic polymer is 0.001 to 1% by weight, based on the total weight of the slurry composition for chemical mechanical polishing.

[0063] The cationic polymer is a polymer or copolymer containing an amine group or an ammonium group.

[0064] The cationic polymer is polydiallyldimethyl ammonium chloride, polyallylamine, polyethyleneimine, polydiallylamine, polypropyleneimine, polyacrylamide-co-diallyldimethyl ammonium chloride, polyacrylamide, poly(trimethylammonio ethylmethacrylate), dicyandiamide-diethylenetriamine copolymer, diallyldimethylamine / hydrochloride-acrylamide copolymer, dicyandiamide-formaldehyde copolymer, or a combination thereof.

[0065] The slurry composition for chemical mechanical polishing has a polishing selectivity of the oxide film / polysilicon film of 200 to 2,000.

[0066] In addition, another embodiment of the present application provides a method for manufacturing a semiconductor device, including a step of polishing using the slurry composition for chemical mechanical polishing.

[0067] Further, another embodiment of the present application provides a semiconductor device including: a substrate; and a groove provided on the substrate and filled with an insulating material, wherein the groove is formed by polishing at least one film selected from a silicon oxide film, a silicon nitride film, and a polysilicon film using a slurry composition for chemical mechanical polishing, wherein the slurry composition for chemical mechanical polishing contains ceria particles and a solvent, and wherein a transmittance of light having a wavelength of 500 nm is 50% or more in a 1.0 wt% aqueous dispersion of the ceria particles.

[0068] Further, another embodiment of the present application provides a method for producing ceria particles for chemical mechanical polishing, including the steps of: preparing a raw material precursor; and pulverizing or precipitating ceria particles in a solution containing the raw material precursor to obtain a dispersion of ceria particles for chemical mechanical polishing, wherein a transmittance of light having a wavelength of 500 nm is 50% or more in a 1.0 wt% aqueous dispersion of the ceria particles.

[0069] Advantageous Effects

[0070] The ceria particles of an embodiment of the present application can have a high oxide film removal rate when contained in a slurry for chemical mechanical polishing at a low content, despite a small particle diameter, by increasing the proportion of Ce 3+ on the surface of the ceria.

[0071] Further, according to an embodiment of the present application, it is possible to provide ceria particles for a slurry composition for chemical mechanical polishing and a slurry composition for chemical mechanical polishing containing the same, which can minimize surface defects of a wafer and maximize an oxide film removal rate while minimizing surface defects, unlike the correlation between surface defects and an oxide film removal rate, which is considered to be a Trade-off relationship in the related art.

[0072] Further, according to an embodiment of the present application, it is possible to further improve the oxide film polishing rate while improving the oxide film / polysilicon film selectivity by adding a cationic polymer. It is a unique effect of the present application that the addition of a cationic polymer is generally considered to sacrifice the polishing rate to secure other characteristics in the related art.

[0073] The effects of the present application are not limited to the above-mentioned effects, and it is to be understood that all the effects that can be deduced from the features of the application described in the detailed description of the application or the claims are included. BRIEF DESCRIPTION OF DRAWINGS

[0074] Figure 1 is a diagram showing an oxide film removal mechanism of an embodiment of the present application.

[0075] Figures 2 to 6 is a cross-sectional view showing a semiconductor device manufacturing method according to an embodiment of the present application, Figure 7 and Figure 8 are a step process of chemical mechanical polishing and a structure of a chemical mechanical polishing (CMP) apparatus, respectively, showing another embodiment of the present application.

[0076] Figure 9 is an image of a dispersion liquid in which cerium oxide particles are dispersed, observed with the naked eye.

[0077] Figure 10 is an image of a dispersion liquid in which cerium oxide particles are dispersed, observed with the naked eye.

[0078] Figures 11 to 13 is a TEM image of cerium oxide particles according to an embodiment of the present application.

[0079] Figure 14 is a SEM image of cerium oxide particles of Comparative Example 1.

[0080] Figure 15 is a SEM image of cerium oxide particles of Comparative Example 2.

[0081] Figure 16 is a SEM and TEM image of cerium oxide particles of Comparative Example 3.

[0082] Figure 17 is a SEM image of cerium oxide particles of Comparative Example 4.

[0083] Figure 18 is a TEM image of Comparative Examples 1 to 3.

[0084] Figure 19 is a particle size analysis result by X-ray Diffraction (XRD) of cerium oxide particles according to an embodiment of the present application.

[0085] Figure 20 is a result of analysis in a small angle X-ray scattering (SAXS) mode of cerium oxide particles according to an embodiment of the present application.

[0086] Figure 21 is a dynamic light scattering (DLS) particle size analysis result of cerium oxide particles according to an embodiment of the present application.

[0087] Figure 22 is a spectral analysis result by Fourier transform infrared (FT-IR) spectroscopy of cerium oxide particles and cerium hydroxide particles according to an embodiment of the present application.

[0088] Figure 23is the result of measuring the transmittance of slurries containing cerium oxide particles of an embodiment of the present invention and conventional cerium oxide particles of Comparative Examples 1 to 4 using ultraviolet-visible light (UV-Vis) spectrophotometry.

[0089] Figure 24 is the intensity ratio and peak area result of X-ray Diffraction (XRD) analysis of cerium oxide particles of an embodiment of the present invention.

[0090] Figure 25 is the X-ray photoelectron spectroscopy (XPS) analysis result of cerium oxide particles of an embodiment of the present invention.

[0091] Figure 26 is the X-ray photoelectron spectroscopy (XPS) analysis result of cerium oxide particles of Comparative Example 3.

[0092] Figure 27 is the Raman peak analysis result of cerium oxide particles of an embodiment of the present invention.

[0093] Figure 28 is the Raman peak analysis result of cerium oxide particles of Comparative Example 1.

[0094] Figure 29 is the Raman peak analysis result of cerium oxide particles of Comparative Example 3.

[0095] Figure 30 is the electron energy loss spectroscopy (EELS) analysis result of cerium oxide particles of an embodiment of the present invention.

[0096] Figure 31 is the electron energy loss spectroscopy (EELS) analysis result of cerium oxide particles of Comparative Example 3.

[0097] Figure 32 is the electron energy loss spectroscopy (EELS) analysis result of cerium oxide particles of Comparative Example 4.

[0098] Figure 33 is the X-ray absorption fine structure (XAFS) spectroscopy analysis result of cerium oxide particles of an embodiment of the present invention.

[0099] Figure 34 is the X-ray absorption fine structure (XAFS) spectroscopy analysis result of cerium oxide particles of Comparative Example 3.

[0100] Figure 35is a graph showing the results of Ultraviolet photoelectron spectroscopy (UPS) analysis of an aqueous dispersion liquid containing 1 mass% of ceria particles of an embodiment of the present application.

[0101] Figure 36 is a graph showing the results of Ultraviolet photoelectron spectroscopy (UPS) analysis of an aqueous dispersion liquid containing 1 mass% of ceria particles of Comparative Example 3.

[0102] Figure 37 is a graph showing the results of Ultraviolet photoelectron spectroscopy (UPS) analysis of an aqueous dispersion liquid containing 1 mass% of ceria particles of Comparative Example 4.

[0103] Figure 38 is the results of BET specific surface area measurement of ceria particles of an embodiment of the present application.

[0104] Figure 39 is the results of BET specific surface area measurement of ceria particles of Comparative Example 1.

[0105] Figure 40 is the results of Photoluminescence (PL) measurement of ceria particles of an embodiment of the present application.

[0106] Figure 41 is the results of Photoluminescence (PL) measurement of ceria particles of Comparative Example 3.

[0107] Figure 42 is the results of Photoluminescence (PL) measurement of ceria particles of Comparative Example 4.

[0108] Figure 43 is a dispersion liquid containing 1 mass% of ceria particles of an embodiment of the present application prepared for measuring colorimetric system.

[0109] Figure 44 is a dispersion liquid containing 1 mass% of ceria particles of Comparative Example 3 prepared for measuring colorimetric system.

[0110] Figure 45 and Figure 46 is a graph showing images of an oxide wafer before and after CMP using a CMP slurry composition containing ceria particles of an embodiment of the present application and using a CMP slurry composition containing 60 nm-level ceria particles.

[0111] Figure 47 Table 1 is a result of measuring the oxide film polishing rate behavior as the cationic polymer is added to the CMP slurry composition containing the ceria particles of an embodiment of the present application. DETAILED DESCRIPTION

[0112] Hereinafter, embodiments of the present application will be described in detail so that those skilled in the art can easily implement the present application. The present application can be implemented in a variety of different forms, and is not limited to the embodiments described herein.

[0113] Preparation Example 1: Preparation of Ceria Particles

[0114] The ceria particles of an embodiment of the present application can be chemically synthesized in a bottom up manner. In an embodiment of the present application, the ceria particles are prepared by any one of ceria particle preparation methods selected from the following.

[0115] According to the preparation method of an embodiment of the present application, first, about 2 to 4 kg of cerium nitrate is added to a sufficient amount of deionized water and stirred. Nitric acid is added to the precursor solution to adjust the pH to 1.0 or less. Ammonia is added to the prepared mixture and stirred until a precipitate is generated. It is confirmed that the pH of the stirred mixture is strongly acidic (2 or less), and if left to stand after completion of stirring, the product is rapidly precipitated. After removing the supernatant except for the precipitate, a prescribed amount of deionized water is added, and a light yellow ceria particle dispersion liquid is generated. The prepared dispersion liquid is circulated and filtered through a membrane filter, and a transparent yellow ceria dispersion liquid is obtained.

[0116] According to the preparation method of another embodiment of the present application, first, 150 g of ceria or cerium hydroxide is dispersed in 3 kg of deionized water and stirred to prevent the particles from precipitating. Nitric acid is added to the mixture until the pH reaches 1.0 or less. The mixture is added to a mill filled with 0.05 mm zirconia beads and circulated and pulverized at 4,000 rpm. As the milling proceeds, it is observed that the white opaque ceria dispersion liquid gradually changes to a yellow transparent ceria dispersion liquid. After completion of the milling, the prepared yellow transparent ceria dispersion liquid is circulated and filtered through a membrane filter, and a pure yellow transparent ceria dispersion liquid is obtained.

[0117] The manufacturing method according to another embodiment of the present application, first, about 2 to 4 kg of cerium ammonium nitrate is added to an adequate amount of ethanol and stirred. An imidazole solution is added to the precursor solution and stirred until a precipitate is generated. It is confirmed that the pH of the stirred mixture is strongly acidic (2 or less), and if left to stand after stirring is completed, the product precipitates rapidly. After removing the supernatant except for the precipitate, a prescribed amount of deionized water is added, and a cerium oxide particle dispersion liquid is generated. The manufactured dispersion liquid is circulated and filtered through a membrane filter, and a transparent cerium oxide dispersion liquid is obtained.

[0118] The manufacturing method according to another embodiment of the present application, first, 1.1 kg of cerium nitrate and 10 kg of deionized water are mixed in a reaction vessel. The stirring speed of the reaction vessel is maintained at 200 rpm, and the temperature is maintained at room temperature. After preparing a 1:1 mixture of 25% ammonia solution and deionized water, it is added to the reaction vessel until the pH value reaches 7.0. After stirring for one hour, a 1:1 mixture of 70% nitric acid and deionized water is added until the pH value reaches 1.0. After the temperature of the reactor is raised to 100°C, a reaction is performed for four hours. During the reaction, the large purple particles dissociate and yellow transparent cerium oxide nanoparticles are generated. The obtained particles are circulated using a membrane filter to remove impurities, and a pure cerium oxide nanoparticle dispersion liquid is obtained.

[0119] Manufacturing Example 2: Manufacturing of CMP Slurry Containing Cerium Oxide Particles

[0120] The cerium oxide particles manufactured in the manufacturing example 1 are added to deionized water, and the polishing material concentration is adjusted to 0.05% by weight, and triethanolamine is added to adjust the pH value to 5.5, to manufacture a CMP slurry.

[0121] According to Figure 9 and Figure 10 The turbidity of the slurry containing the existing cerium oxide particles can be observed with the naked eye to be high, and in contrast, the slurry containing the cerium oxide particles of the present application can be observed to be transparent, and thus it can be inferred to have monodisperse properties.

[0122] Comparative Examples 1 to 4: Manufacturing of Slurry Composition Containing Existing Cerium Oxide Particles

[0123] Commercially available wet cerium oxide particles having average particle diameters of 10, 30, and 60 nm, respectively, and 10 to 20 nm grade cerium oxide particles manufactured separately by a calcination method are each added to deionized water, the polishing material concentration is adjusted to 0.05% by weight, ammonia is added as a pH adjuster, and finally the pH value is adjusted to 5.5, to manufacture a CMP slurry.

[0124] Experimental Example 1: SEM and TEM analysis of ceria particles

[0125] The dispersion liquid of Manufacturing Example 1 of an embodiment of the present application was dried at about 80 to 90°C to prepare ceria particles (primary particles) in powder form (Sample A). On the other hand, ceria particles used in preparing the dispersion liquids of Comparative Examples 1 to 4 were prepared (Samples Bl, B2, B3, and B4, respectively). The prepared samples were each subjected to image capturing using a TEM measurement instrument.

[0126] Figures 11 to 13 is a TEM image of ceria particles of an embodiment of the present application.

[0127] Referring to Figures 11 to 13 The TEM measurement results of ceria particles produced according to an embodiment of the present application showed that the average particle diameter was about 4 nm or less (3.9 nm, 3.4 nm, 2.9 nm, respectively, in repeated measurements). It was found that the average primary particle diameter of ceria particles of an embodiment of the present application was 4 nm or less. In addition, it was confirmed that the ceria particles generally had the shape of spherical particles. Spherical ceria particles having a small particle diameter and a relatively uniform size distribution could have a large specific surface area, and were excellent in dispersion stability and storage stability.

[0128] Figures 14 to 17 is a graph showing an SEM image of conventional ceria particles of a comparative example.

[0129] Referring to Figures 14 to 17 , conventional commercially available ceria particles have particle diameters corresponding to each size class, and particles produced by a calcination method have an average primary particle diameter of more than 10 nm, and it was confirmed that the average particle diameter of ceria particles of an embodiment of the present application shown in Figures 11 to 13 was 4 nm or less as measured by TEM, compared with the conventional ceria particles and ceria particles produced by a general calcination method. In contrast, it was confirmed that the particle diameter of ceria particles of the present application (primary particles) was small as such, and it was predicted that the smaller the ceria particle diameter, the more the defects such as scratches on the surface of a polishing target film could be reduced.

[0130] In addition, Figure 18 shows a TEM image of conventional ceria particles of a comparative example. Referring to Figure 18, the existing cerium oxide particles having a particle size of 10 nm include particles having edges and spherical particles, and the existing cerium oxide particles having a particle size of 30 nm or more are angular particles having edges. In contrast, as described above, the cerium oxide particles of the embodiment of the present application are substantially spherical, and the cerium oxide particles of the present application have a spherical particle shape and a small particle size as such, so that a large number of particles can be included, and thus, the probability of surface defects occurring when polishing a silicon oxide film can be reduced, and the global flatness can be improved.

[0131] Experimental Example 2: X-ray Diffraction (XRD) analysis of cerium oxide particles

[0132] The dispersion liquid of Manufacturing Example 1 of the embodiment of the present application was dried at about 80 to 90°C to prepare cerium oxide particles (primary particles) in a powder form (Sample A). The prepared Sample A was analyzed using an XRD instrument (Rigaku, Ultima IV). At this time, the XRD was set to Cu Kα 40 kV and 40 mA.

[0133] Figure 19 is an X-ray Diffraction (XRD) pattern of cerium oxide particles of the embodiment of the present application. The particle size of the cerium oxide particles derived from the analysis of the XRD pattern is shown in Table 1 below.

[0134] [Table 1]

[0135]

[0136] Referring to Figure 19 and Table 1, for the XRD analysis results of Sample A, it was derived that the cerium oxide particles of the embodiment of the present application have a particle size of 10 nm or less, and the cerium oxide particles of the embodiment of the present application have a particle size of 10 nm or less. Figure 7 Experimental Example 3: Small Angle X-ray Scattering (SAXS) analysis of cerium oxide particles

[0137] The particle size of the cerium oxide particles of the embodiment of the present application was analyzed using a small angle X-ray scattering (SAXS) method and is shown in

[0138] Figure 20

[0139] Referring to Figure 20 ​​, the average particle radius of the cerium oxide particles of the embodiment of the present application was confirmed to be 2.41 nm, and thus the particle diameter had a range of 10 nm or less. It was thus confirmed that the particle diameter of the cerium oxide particles of the embodiment of the present application was significantly smaller than that of the conventional cerium oxide particles, and thus the occurrence of defects on the surface was more suppressed when the cerium oxide particles of the embodiment of the present application were used to polish a silicon oxide film.

[0140] Experimental Example 4: Dynamic Light Scattering (DLS) Particle Size Analyzer Analysis of Cerium Oxide Particles

[0141] The slurry composition of Manufacturing Example 2 of an embodiment of the present application, the slurry compositions of Comparative Examples 1, 2, 3, and 4 were prepared as samples. The prepared samples were each analyzed using a DLS device.

[0142] Figure 21 is a result of dynamic light scattering (DLS) analysis (Malvern, Zetasizer Ultra) of cerium oxide particles of an embodiment of the present application. In addition, Table 2 below shows D50 values obtained based on dynamic light scattering (DLS) analysis of cerium oxide particles of an embodiment of the present application and cerium oxide particles of a plurality of comparative examples.

[0143] [Table 2]

[0144] Test sample D50 value (nm) Example of the present invention 5.78 Comparative Example 1 - existing 10 nm grade ceria particles 33.6 Comparative Example 2 - existing 30 nm grade ceria particles 93.9 Comparative Example 3 - existing 60 nm grade ceria particles 138.7 Comparative Example 4 - ceria particles made by calcination method 139.1

[0145] Referring to Figure 21 and Table 2, the cerium oxide particles of the embodiment of the present application were measured to have a secondary particle diameter D50 value of about 5.78 nm, which was 10 nm or less. This was about 148% to 199% relative to the primary particle diameter measured by TEM in Experimental Example 1 (refer to Figures 11 to 13 ), and it was confirmed that there was almost no aggregation in the slurry and the particles were monodispersed, and the particle diameter was almost unchanged.

[0146] In contrast, the D50 particle diameter of the conventional cerium oxide particles measured by dynamic light scattering (DLS) was greater than 30 nm, and the D50 value of the secondary particle diameter of the 10 nm-level cerium oxide particles measured by dynamic light scattering (DLS) was about 336% relative to the primary particle diameter measured by TEM, and the conventional cerium oxide particles had a significantly larger secondary particle diameter, and thus it was confirmed that a large amount of aggregation occurred.

[0147] Thus, the cerium oxide particles of an embodiment of the present application had less aggregation in the slurry than the conventional cerium oxide particles of a comparative example, and were able to be dispersed in the slurry in a more monodispersed form.

[0148] Experimental Example 5: Confirmation of formation of cerium oxide particles by Fourier transform infrared (FT-IR) spectroscopic analysis

[0149] Figure 22 The results of FT-IR spectroscopic analysis of a powder composed of cerium oxide particles made according to an embodiment of the present application and a powder composed of conventional cerium hydroxide particles.

[0150] According to Figure 22 the results of FT-IR spectroscopic analysis of a powder composed of cerium oxide particles made according to an embodiment of the present application, the infrared transmittance in the range of 3000 cm -1 ~ 3600 cm -1 was about 92 ~ 93%, and the infrared transmittance in the range of 720 cm -1 ~ 770 cm -1 was about 93 ~ 95%. In the FT-IR spectrum of a powder composed of conventional cerium hydroxide particles, the infrared transmittance in the range of 3000 cm -1 ~ 3600 cm -1 was 75 ~ 90%, and the infrared transmittance in the range of 720 cm -1 ~ 770 cm -1 was 97 ~ 99%, as compared with which it could be confirmed that the cerium hydroxide particles made according to an embodiment of the present application showed a weaker hydroxyl (O-H group) band of cerium hydroxide particles in the range of 3000 cm -1 ~ 3600 cm -1 and formed a peak based on Ce-O stretching in the range of 720 cm -1 ~ 770 cm -1 . Thus, the results can indicate that the cerium compound made according to an embodiment of the present application is cerium oxide.

[0151] Experimental Example 6: Measurement of light transmittance of slurry containing cerium oxide particles

[0152] A slurry composition (Sample A) was prepared in the same manner as in Production Example 2, except that the weight ratio of cerium oxide particles in the CMP slurry was 1 wt%. On the other hand, slurry compositions (Samples Bl, B2, B3 and B4, in that order) were prepared in the same manner as in Comparative Examples 1, 2, 3 and 4, respectively, except that the weight ratio of cerium oxide particles in the CMP slurry was 1 wt%. The transmittance of each sample for light of 200 ~ 1100 nm was measured using a UV-Vis spectrometer (JASCO).

[0153] Figure 23The transmittance of slurries containing cerium oxide particles from an embodiment of the present invention and conventional cerium oxide particles from Comparative Examples 1 to 4 was measured using ultraviolet-visible (UV-Vis) spectrophotometry.

[0154] Cerium oxide particles from one embodiment of the present invention and several comparative examples were added to deionized water, and the concentration of the grinding material was adjusted to 1.0 wt% to prepare a CMP slurry, and the transmittance was analyzed. At this time, the spectrum in the range of 200–1,100 nm was measured using a Jasco UV-vis spectrophotometer.

[0155] Based on the UV-Vis analysis spectra, the transmittance (%) of samples A and samples B1 to B4 at wavelengths of 500 nm, 600 nm and 700 nm, respectively, was compiled and is shown in Table 3 below.

[0156] [Table 3]

[0157]

[0158] according to Figure 23 According to Table 3, it can be confirmed that the slurry containing the cerium oxide particles of the present invention has an average transmittance of 50% or more for light with wavelengths of 450 to 800 nm. In addition, it can be confirmed that the transmittance for light with a wavelength of about 500 nm is 90% or more, and the transmittance for light with wavelengths of about 600 nm and 700 nm is 95% or more.

[0159] On the other hand, the transmittance of slurries containing conventional cerium oxide particles (10nm, 30nm, and 60nm in size, and calcined cerium oxide particles) from Comparative Examples 1-4 was measured. The transmittance of Comparative Example 4 (calcined cerium oxide particles) was almost 0%, and the transmittance of the slurry from Comparative Example 1, containing commercially available conventional cerium oxide particles at the 10nm level, was on average less than 80%, with a transmittance of less than 50% at a wavelength of 500nm. Comparative Examples 2 and 3 had relatively large primary particle sizes of 30nm and 60nm, respectively, and their secondary particle sizes were also larger than those of the embodiments of the present invention (i.e., stronger cohesion in the slurry), therefore, their transmittance in the visible light region was less than 20%.

[0160] Conversely, the cerium oxide particles of one embodiment of the present invention have a transmittance of over 90% in the visible light region. This means that the primary particle size of the cerium oxide particles of the present invention is small, resulting in less aggregation into secondary particles compared to existing cerium oxide particles. Typically, when secondary particles are larger than 20 nm, the slurry composition can also be observed to be opaque with the naked eye, and the transmittance to wavelengths in the visible light region is less than 80%.

[0161] The slurry composition according to the present application, when the primary particle diameter of the cerium oxide particles is small and the agglomeration of the secondary particles is weak, has high dispersion stability, and thus the particles can be uniformly distributed, and when a slurry composition containing the particles is used to polish a polishing target film, the probability of reducing defects such as scratches on the surface can be easily predicted by the light transmittance.

[0162] Experimental Example 7: Peak area ratio of cerium oxide particles based on XRD analysis

[0163] Figure 24 The intensity ratio and peak area results of cerium oxide particles according to an embodiment of the present application by X-ray Diffraction (XRD) analysis.

[0164] According to the XRD analysis results of Figure 24 , it can be confirmed that the peak area of the (111) plane of the cerium oxide particles according to an embodiment of the present application is about 496.9, and the peak area of the (200) plane is about 150.1. At this time, the ratio of the peak area of the (111) plane to the peak area of the (200) plane is about 3.3. By searching the main peak in the molecular library, it can be confirmed that the particles according to the embodiment of the present application are cerium oxide particles.

[0165] Experimental Example 8: XPS analysis of cerium oxide particles

[0166] Figure 25 and Figure 26 are the XPS analysis results of the cerium oxide particles according to an embodiment of the present application and the existing cerium oxide particles of the 60 nm level of Comparative Example 3. X-ray photoelectron spectroscopy (XPS) can measure the peaks appearing at 900.2-902.2 eV, 896.4-898.4 eV, 885.3-887.3 eV, and 880.1-882.1 eV, which represent the Ce 3+ -O binding energy when soft X-rays are irradiated, and the atomic percentage (atomic %) is analyzed by XPS fitting, thereby measuring the content of Ce 3+ and Ce 4+ in the cerium oxide particles. Table 4 below is the XPS result data of the cerium oxide particles according to the embodiment of the present application.

[0167] [Table 4]

[0168]

[0169] Based on the XPS analysis results, the content of Ce 3+ was calculated according to the chemical formula, and the content of Ce 3+more than 30%. In the cerium oxide particles, Ce 3+ is the reactive site, and thus, the polishing amount can be increased. In the above manner, the comparative data with the existing cerium oxide particles are shown in Table 5 below.

[0170] [Table 5]

[0171]

[0172] As shown in Table 5, the Ce 3+ content of the cerium oxide particles of the embodiment of the present application is about 36.9 atomic %, and as can be seen from Table 5, the Ce 3+ content of the existing 60 nm-level cerium oxide particles is lower than 14 atomic %, and the cerium oxide particles of 10 nm-level synthesized by the hydrothermal synthesis method under supercritical or subcritical conditions described in the existing literature is about 16.8%, and thus, has a higher Ce 3+ content. When the surface Ce 3+ content is high as in the embodiment of the present application, the polishing rate for a silicon-containing substrate can be increased by the chemical polishing mechanism of Si-O-Ce formed between silicon dioxide and cerium.

[0173] Experimental Example 9: Analysis of Raman spectroscopy of cerium oxide particles

[0174] Figures 27 to 29 are the analysis results of Raman spectroscopy of the cerium oxide particles of the embodiment of the present application, the existing cerium oxide particles of 10 nm-level, and the existing cerium oxide particles of 60 nm-level, respectively. The analysis results of the derived Raman spectra of the samples of the embodiment, Comparative Example 1, and Comparative Example 3 are shown as Raman spectra (X-axis: Raman shift (cm Figure 27 , Figure 28 and Figure 29 -1), Y-axis: Counts) shown in FIGS. -1 The analysis results of the derived Raman spectra are shown in Table 6 below.

[0175] [Table 6]

[0176]

[0177] Referring to Figures 27 to 29 and Table 6, the existing cerium oxide particles of Comparative Examples 1 and 3 have a first Raman peak around 462 cm -1 , and the cerium oxide particles of the embodiment of the present application have a second Raman peak around 457 cm -1The first Raman peak is present in the vicinity. This can be due to the partial Ce 4+ being reduced to Ce 3+ so that the cubic fluorite crystal structure of the ceria particles is induced to increase oxygen vacancies by defects, and thus the shift of the first Raman peak occurs. In addition, it can be confirmed that the intensity of the second Raman peak of the example sample is higher than that of Comparative Example 1 and Comparative Example 3 due to such a difference in particle structure.

[0178] In addition, it can be confirmed that the ceria particles of the example of the present application respectively exhibit peaks at 457 cm -1 , 607 cm -1 , and 742 cm -1 , and in contrast, Comparative Example 1 and Comparative Example 3 hardly detect the second peak at about 607 cm -1 or exhibit only very weak intensity, and it is confirmed that unlike the example, the third peak at about 742 cm -1 is not detected.

[0179] On the other hand, it is confirmed that in the example, Comparative Example 1, and Comparative Example 3, the ratio A / B of the intensity of the first Raman peak A to the intensity of the second Raman peak B is 15.4, 46.0, and 66.4, respectively, in order. As such, the A / B value of the sample of the example is significantly smaller than that of Comparative Example 1 and Comparative Example 3, and the ratio A / C of the intensity of the first Raman peak A to the intensity of the third Raman peak C of the present example is 50 or less, whereas Comparative Examples 1 and 3 cannot calculate A / C because the third Raman peak is not detected, which can be explained as a result of an increase in the proportion of defects (oxygen vacancies) due to an increase in the Ce 3+ content in the ceria particles.

[0180] From the results, it can be predicted that the ceria particles of an example of the present application contain a high content of Ce 3+ compared to the existing ceria particles of the comparative examples.

[0181] Experimental Example 10: Electron Energy Loss Spectroscopy (EELS) Analysis of Ceria Particles

[0182] The slurry composition of the example of the present application of Preparation Example 2, the slurry composition of Comparative Example 3, and the slurry composition of Comparative Example 4 were prepared as samples, respectively.

[0183] The prepared samples were analyzed using an EELS measuring instrument. The EELS measurement was performed for a high loss region as an energy loss range of 50 eV or more. The ionization edge occurring in the high loss region was used to distinguish the oxidation state-based peaks of the measured samples, and thus the Ce content of the cerium oxide particles was quantitatively analyzed. 4+

[0184] According to the results of the sample analysis by the EELS measuring instrument, the EELS spectra (X-axis: binding energy (eV), Y-axis: intensity (a.u.)) shown in FIGS. 1 to 3 were derived for the samples of the example, Comparative Example 3, and Comparative Example 4, respectively, in order. Figures 30 to 32

[0185] According to the analysis results, the EELS spectrum of the example included a first peak of about 876.5 to 886.5 eV, a second peak of 894.5 to 904.5, and the maximum intensity of the first peak was greater than that of the second peak, following the EELS spectrum trend of Ce 3+ . In contrast, in the EELS spectra of Comparative Examples 3 and 4, the maximum peak intensity of the second peak was greater than that of the first peak, following the EELS spectrum trend of Ce 4+ . This indicates that the cerium oxide particles of the example follow the EELS spectrum trend of Ce 3+ , while the cerium oxide particles of Comparative Examples 3 and 4 follow the EELS spectrum trend of Ce 4+ .

[0186] On the other hand, the EELS spectrum of the cerium oxide particles can further include a third peak range of 886.5 to 889.5 eV and a fourth peak range of 904.5 to 908.5 eV, and the peak areas of the third and fourth peak ranges can represent the peaks of the oxidation state of Ce 4+ in the cerium oxide particles. Based on the EELS spectrum in Figures 30 to 32 , the peak area ratio for a specific binding energy range was derived and shown in Tables 7 to 9 (the result data of the example, Comparative Example 3, and Comparative Example 4, in order). According to the EELS spectrum analysis results, it was calculated that the ratio P1 / P t of the sum of the areas of the third peak range P1 to the total sum of the areas of the peaks P t of the EELS was 1%, 1%, 0%, and 0% in the cerium oxide particles of the example, 3%, 3%, 4%, and 4% in Comparative Example 3, and 3%, 3%, 3%, and 4% in Comparative Example 4.

[0187] ​​In addition, the area P1 of the third peak interval and the area P2 of the fourth peak of the cerium oxide particles of one embodiment of the present application with respect to the total area sum P of the peaks of the EELS t The area ratio (P1+P2) / P t of the third peak interval and the fourth peak of the cerium oxide particles of one embodiment of the present application is approximately 5.8% or less, whereas that of Comparative Example 3 is 13% or more, and that of Comparative Example 4 is approximately 12% or more, and thus it can be confirmed that the cerium oxide particles of one embodiment of the present application have a lower Ce 4+ content than the cerium oxide particles of Comparative Examples 3 and 4.

[0188] [Table 7]

[0189]

[0190] [Table 8]

[0191]

[0192] [Table 9]

[0193]

[0194] Experimental Example 11: X-ray absorption fine structure (XAFS) spectroscopic analysis of cerium oxide particles

[0195] The slurry composition of Production Example 2 of one embodiment of the present application and the slurry composition of Comparative Example 3 were each prepared as a sample.

[0196] Each of the prepared samples was analyzed using an XAFS measuring instrument. The XAFS is an analysis method in which a high-intensity X-ray is irradiated to a sample to measure the intensity of the absorbed X-ray, the absorption coefficient (xμ) is measured as a function of the X-ray energy (eV), the X-ray absorption spectrum is derived, and on the basis thereof, the weight ratio (wt%) of Ce 3+ and Ce 4+ in the particles is confirmed. At this time, the absorption spectrum was derived by an X-ray absorption near edge structure (XANES) method in which the XAFS spectrum within 50 eV in the vicinity of the absorption edge at which the X-ray absorption sharply increases was analyzed.

[0197] According to the results of the XAFS analysis of the samples of the embodiment and Comparative Example 3, respectively, the XAFS spectra (X axis: X-ray energy (eV), Y axis: X-ray absorption coefficient xμ(E)) shown in Figure 33 and Figure 34 were derived. As shown in Figure 33 andFigure 34 The absorption edge of each of the samples of the example and Comparative Example 3 was formed in the range of about 5745 to 5755 eV. On the other hand, the peak P1 in which strong electron migration occurs due to X-ray absorption of Ce 3+ was formed in the range of about 5735 to 5740 eV, and the peak P2 in which strong electron migration occurs due to X-ray absorption of Ce 4+ was formed in the range of about 5745 to 5755 eV.

[0198] According to the results of the study on the absorption coefficients of the P1 and P2, the example of the present application was about 0.1 to 0.2 and 0.5 to 0.6, respectively, and Comparative Example 3 was less than 0.1 and more than 0.6, respectively.

[0199] According to the analysis results, the peak areas and the area ratios of Ce 3+ and Ce 4+ of each of the samples of the example and Comparative Example 3 were as shown in Table 10 below.

[0200] [Table 10]

[0201]

[0202] Referring to Table 10, the area ratio of Ce 3+ on the surface of the cerium oxide particles of the example of the present application was about 4 times or more the area ratio of Ce 3+ on the surface of the cerium oxide particles of Comparative Example 3, and thus it was predicted that the example of the present application could have a higher polishing rate than the existing cerium oxide particles of Comparative Example.

[0203] Experimental Example 12: UPS analysis of cerium oxide particles

[0204] Samples of cerium oxide particles of an example of the present application, Comparative Examples 3 and 4 were prepared.

[0205] Figures 35 to 37 are the UPS analysis results of cerium oxide particles of an example of the present application, 60 nm-class existing cerium oxide particles, and existing cerium oxide particles prepared by a calcination method.

[0206] The work function values of cerium oxide particles of an example of the present application and the existing cerium oxide particles were summarized in Table 11.

[0207] In one embodiment, the maximum value of the number of photoelectrons released per second (Counts, Y axis) of the cerium oxide particles of one embodiment of the present application is in the kinetic energy range of 8 to 10 eV, while that of Comparative Example 3 and Comparative Example 4 is in the kinetic energy range of 11 to 13 eV. From this result, it can be derived that the work function of the embodiment is 3.16 eV, and the work functions of Comparative Example 3 and Comparative Example 4 are 2.37 eV and 2.37 eV, respectively.

[0208] In one embodiment, the UPS analysis can derive the binding energy E kin from the measured kinetic energy E b , and then derive the Fermi level EFand the vacuum level E cutoff of the plurality of samples from the derived binding energy spectrum. Thus, the Fermi level E F and the vacuum level E cutoff values can be substituted into the following Equation 1 to obtain the work function φ value. At this time, hv is the source energy used when emitting ultraviolet light, and represents the energy of the incident light, and the source uses helium (He) (He | UPS = 21.22 eV). The work function values obtained from the analysis results are shown in Table 11 below.

[0209] [Equation 1]

[0210] φ = hv - |E f -E cutoff |

[0211] [Table 11]

[0212] Category Work function (eV) Example of the present invention 3.16 Comparative Example 3 2.37 Comparative Example 4 2.37

[0213] As can be seen from Table 11, the work function value of the cerium oxide particles of one embodiment of the present application is the largest. The smaller the particle size of the particles, the greater the energy level difference between the plurality of orbitals of the sample, and thus the higher the energy band gap. The cerium oxide particles of one embodiment of the present application are sufficiently smaller in particle size than the existing cerium oxide particles, and thus have a higher energy band gap, which affects the Fermi level and the vacuum level, thereby changing the energy value of the work function. Thus, according to the work function value derived through the UPS analysis, the cerium oxide particles of one embodiment of the present application are sufficiently smaller in particle size than the existing cerium oxide particles, and have very weak coaggregation. Due to such low coaggregation and monodispersibility, the cerium oxide particles of one embodiment of the present application, when used in a manner of being contained in a slurry for chemical mechanical polishing, can maximize the number of particles in contact with a wafer, and can minimize defects on the wafer surface while improving the polishing rate of the oxide film, due to the small particle size itself.

[0214] Experimental Example 13: BET Specific Surface Area Analysis of Cerium Oxide Particles

[0215] To measure the BET specific surface area, 1.0 g of the ceria particle powder of the present application example and 1.0 g of the ceria particle powder of Comparative Example 1 were each subjected to a pretreatment of degassing at 200°C for 1 hour until the residual pressure reached a predetermined value or less, after which the nitrogen adsorption amount at the time of relative pressure increase was measured at 77K using BET (Tristar II plus, Micrometrics), and the BET specific surface area value calculated from the adsorption amount is shown in Table 12 below. Figure 38 and Figure 39 and Table 12 below.

[0216] [Table 12]

[0217]

[0218] Referring to Table 12, when the ordinary pretreatment conditions (200°C, 1 hour) were employed, the BET specific surface area value of the ceria particle powder of the present application example measured 5 times under the same conditions was 50 m 2 / g or less, in contrast, the BET specific surface area value of the ceria particle powder of Comparative Example 1 measured 5 times under the same conditions was greater than 80 m 2 / g. Such a value of the comparative example is similar to the BET specific surface area value of the 10 nm order ceria particles described in conventional literature.

[0219] From this result, it can be confirmed that the ceria particle powder of the present application example has a smaller BET specific surface area value than the ceria particle powder of Comparative Example 1 having a more coarse particle diameter, which indicates that the ceria particles of the present application example are more minute in particle diameter than existing ceria particles, and thus can be filled at a higher density when forming a powder, and in addition, for the same reason, the ceria particles synthesized by a self-organizing synthesis method such as a sol-gel method, bottom-up method, etc. have fewer -OH functional groups than ceria particles synthesized by other synthesis methods, and thus have a smaller BET specific surface area and pore volume.

[0220] Experimental Example 14: Apparent Density Analysis of Ceria Particles

[0221] The dispersion liquid of Production Example 1 of an embodiment of the present application was dried at about 80 to 90°C to prepare ceria particles in powder form (Sample A), and ceria particles in powder form of Comparative Examples 3 and 4 dried under the same conditions were prepared (Samples B and C, respectively). Table 13 and Table 14 below show the apparent density and tap density determined for the prepared Sample A of an embodiment of the present application and Comparative Examples 3 and 4.

[0222] [Table 13]

[0223]

[0224] [Table 14]

[0225] Test sample Sample A (Example) Sample B (Comparative Example 3) Sample C (Comparative Example 4) Tap density (g / mL) 2.94 2.86 1.60

[0226] Referring to Table 13, the apparent density of Sample A measured based on the static method was 2.22 g / mL, while the apparent density of the 60 nm-level ceria particles of Comparative Example 3 was 1.90 g / mL, and the apparent density of the calcined ceria particles of Comparative Example 4 was 1.90 g / mL. In addition, referring to Table 14, the apparent density of Sample A measured based on the vibration method was 2.94 g / mL, while the apparent density of the 60 nm-level ceria particles of Comparative Example 3 was 2.86 g / mL, and the apparent density of the calcined ceria particles of Comparative Example 4 was 1.60 g / mL, which was less than 2.90 g / mL. Thus, it can be confirmed that the ceria particles of an embodiment of the present application, although having a smaller primary particle diameter, have a greater apparent density value than the ceria particles of the comparative examples having a larger particle diameter. Therefore, the ceria particles of the embodiment of the present application, which are 10 nm or less, not only have a smaller particle diameter than the existing ceria particles, but also have the characteristic of having a relatively large apparent density value.

[0227] Experimental Example 15: Photoluminescence (PL) measurement analysis of a dispersion liquid containing ceria particles

[0228] Figures 40 to 42 and Table 15 shows the results of photoluminescence intensity measurement of water dispersion liquids each containing 1 mass% of ceria particles of an embodiment of the present application, existing 60 nm-level ceria particles, and 10 nm-level ceria particles based on a calcination method, respectively. The photoluminescence intensity was measured under the following test conditions.

[0229] (1) Test instrument: Perkin Elmer LS-55 Fluorescence Spectrometer

[0230] (2) Excitation wavelength: 325 nm

[0231] (3) Emission filter: 350 nm

[0232] (4) Excitation slit width: 10.0 nm

[0233] (5) Emission slit width: 10.0 nm

[0234] [Table 15]

[0235]

[0236] Referring to Figures 40 to 42 and Table 15, according to analysis by a fluorescence spectrometer using an excitation wavelength λ excitation of 325 nm, all of the three samples had an excitation peak λ exc at a wavelength of 325 nm, a first emission peak λ ems1 at a wavelength of about 450 nm, and a second emission peak λ ems2 .

[0237] The ratio λ ems1 / λ ems2 of the first emission peak to the second emission peak of the cerium oxide particles of the present application was about 7.5, which is a value of 5 or more. In contrast, the ratio λ ems1 / λ exc of the first emission peak to the excitation peak of the existing 10 nm-level cerium oxide particles based on the calcination method and the commercially available 60 nm-level cerium oxide particles was more than 30, and the ratio λ ems1 / λ ems2 of the first emission peak to the second emission peak was less than 5.

[0238] The intensity of the first emission peak representing Ce 3+ of the cerium oxide particles of the present application was less than that of the existing 10 nm-level cerium oxide particles based on the calcination method and the commercially available 60 nm-level cerium oxide particles, which is considered to be because the cerium oxide particles of the present application are rarely aggregated into secondary particles in a dispersion liquid, and thus have good light transmission, and thus have weak emission intensity. In addition, unlike the existing 60 nm-level particles or the cerium oxide particles based on the calcination method, the ratio λ ems1 / λ ems2 of the first emission peak to the second emission peak of the cerium oxide particles of the present application was a value of 5 or more, which is explained to be because the surface of the cerium oxide particles of the present application has a relatively higher Ce 3+ content. Thus, it is known from the present experimental example that the Ce 3+ content of the surface of the particles is high, and the particles themselves are small, and have a characteristic of being rarely aggregated in a slurry, and thus, when used in a slurry for chemical mechanical polishing, the chemical polishing rate based on the Si-O-Ce bond between the cerium oxide particles and the oxide film substrate is increased, and thus, the oxide film polishing rate is increased.

[0239] Experimental Example 16: L*a*b* Color System Analysis of Dispersion Liquid Containing Ceria Particles

[0240] Figure 43 and Figure 44 is a water dispersion liquid containing 1 mass% of ceria particles of an embodiment of the present application and a water dispersion liquid containing 1 mass% of existing 60 nm grade ceria particles.

[0241] The chromaticity values of the dispersion liquid containing 1 mass% of ceria particles of an embodiment of the present application and the dispersion liquid containing 1 mass% of existing 60 nm grade ceria particles, expressed by L*a*b* color system, are collated in Table 16 and Table 17.

[0242] In one implementation, the analysis of L*a*b* color system is performed by the method of ASTM El 164 (Standard practice for obtaining spectrometric data for object color Evaluation) using CM-5 (KONICA MINOLTA, JAPAN), when the light source uses Xenon lamp D65, in the wavelength range of 360 to 740 nm, with 10 nm wavelength interval. The analysis results are shown in Table 16 and Table 17 as follows.

[0243] [Table 16]

[0244]

[0245]

[0246] [Table 17]

[0247] Cerium oxide particles of 60 nm grade L* (unitless) a* (unitless) b* (unitless) 1 94.73 -2.19 0.13 2 94.72 -2.19 0.13 3 94.71 -2.18 0.13 Standard deviation 0.01 0.01 0.00 CV (%) 0.01 -0.26 0.00 Average 94.72 -2.19 0.13

[0248] With reference to Figure 43 and Figure 44 , the water dispersion liquid containing ceria particles of the present application can be observed to be yellowish with the naked eye, while the water dispersion liquid containing existing 60 nm grade ceria particles is opaque and closer to white.

[0249] In addition, with reference to Tables 16 and 17, the average value of L* of the dispersion liquid containing 1 mass% of the cerium oxide particles of one embodiment of the present application was about 99.7, the average value of a* was about -5.9, and the average value of b* was about 11.7. In contrast, the average value of L* of the dispersion liquid containing the existing 60 nm grade cerium oxide particles was about 94.7, the average value of a* was about -2.2, and the average value of b* was about 0.1. Thus, the cerium oxide particle dispersion liquid of the present application had an L* value of 95 or more and a b* value in the range of 10 to 25, and had a larger L* value than the existing 60 nm grade cerium oxide particle dispersion liquid, and thus was known to have a characteristic of having fine particles, and because it had a larger b* value, the cerium oxide particle dispersion liquid of one embodiment of the present application appeared more yellow. When expressed using the L*a*b* color system, the water dispersion liquid containing the cerium oxide particles of one embodiment of the present application had each value in the above range, and in particular, had a high yellow degree, which indicated that the cerium oxide particles were very fine and exhibited a characteristic of monodispersion, and in addition, the Ce 3+ content on the surface of the cerium oxide particles was relatively high.

[0250] Experimental Example 17: Sedimentation rate of cerium oxide particles during centrifugal separation

[0251] A slurry composition containing 1.0% by weight of cerium oxide particles of one embodiment of the present application, a slurry composition containing 1.0% by weight of cerium oxide particles of Comparative Example 1, and a slurry composition containing 1.0% by weight of cerium oxide particles of Comparative Example 3 were prepared as samples, respectively.

[0252] Using the samples, a high-speed centrifugal separator or an ultra-high-speed centrifugal separator (Hanil Science Co., Ltd., Model: Supra R22) was used to perform centrifugal separation from a condition in which the temperature of the slurry composition was 25°C, in a manner in which the centrifugal force was changed to 2100 G, 3300 G, 4265 G, 26188 G, and 398282 G, and the sedimentation rate of the cerium oxide particles was shown in Table 18 below.

[0253] [Table 18]

[0254]

[0255] Referring to Table 18, it can be seen that, when each slurry composition containing 1.0 wt% of ceria particles was subjected to centrifugal separation, the settling rate of the ceria particles of the embodiment of the present application was less than that of the ceria particles of Comparative Example 1 and Comparative Example 3 under the same conditions. For example, when centrifugal separation was performed at a centrifugal force of 4,265 G for 30 minutes, the settling rate of the embodiment of the present application was 0 wt%, whereas the settling rate of Comparative Example 1 was 27.14 wt%, and the settling rate of Comparative Example 3 was already 96.9 wt% when centrifugal separation was performed at a centrifugal force of 3,300 G, which is less than this, for 10 minutes. Thus, this indicates that the primary particle diameter and / or the secondary particle diameter of the ceria particles of the embodiment of the present application are more minute than those of the ceria particles of Comparative Examples 1 and 3, and that the ceria particles are monodispersed, and thus, in a chemical mechanical polishing process, the number of contact particles increases due to the contact of the monodispersed particles with a wafer, thereby improving the polishing rate of an oxide film, and, when polishing is performed using a slurry composition containing the ceria particles of the embodiment of the present application, it is possible to reduce the probability of occurrence of polishing defects such as scratches on a wafer being polished.

[0256] Experimental Example 18: Analysis of Residual Amount of Ceria Precursor

[0257] The residual amount of a precursor in the CMP slurry containing ceria particles manufactured in Manufacturing Example 2 was measured. After the slurry sample of Manufacturing Example 2 was manufactured in a powder form by a process of drying at a high temperature until a powder was obtained, the residual powder was re-dissolved in purified water. The content of the precursor in the solution dissolved in purified water was analyzed by ICP-MS, and converted into a weight ratio of ceria powder, and as a result, it was confirmed that an alkaline substance, a solvent, ammonia, etc. were hardly detected, and were 300 ppm or less. More specifically, units indicating a content significantly less than PPM or not containing were hardly detected. Thus, since the ceria particles are appropriately distributed in the slurry, and hardly contain ceria precursor, an alkaline substance, and other impurities that can be generated depending on the characteristics of a wet process, it can be predicted that the ceria particles of an embodiment of the present application, after being formed in a dispersion liquid form by a wet process, do not need a process of being re-dispersed in a slurry solvent through an additional separation or pulverization process, etc.

[0258] [Table 19]

[0259]

[0260] Experimental Example 19: Oxide Film Polishing Rate Comparison of Ceria Particles

[0261] A slurry composition of Manufacturing Example 2 of an embodiment of the present application, a slurry composition of Comparative Example 1, and a slurry composition of Comparative Example 3 were prepared as samples, respectively.

[0262] A polisher (K-4000, manufactured by KOSO Corporation) was used. LK CMP, Applied Materials) was performed on the oxide film wafer using the sample. Specifically, a PE-TEOS silicon oxide film wafer (300 mm PE-TEOS Wafer) was mounted on a platen, and the surface of the wafer was brought into contact with a pad (IC1010, DOW) of the polisher. Next, the slurry composition of the sample was supplied at a rate of 200 mL / min, and the platen and the pad of the polisher were rotated to perform the polishing process. At this time, the rotation speed of the platen and the rotation speed of the head were 67 rpm / 65 rpm, the polishing pressure was 2 psi, and the polishing time was 60 seconds. On the other hand, the thickness of the silicon oxide film of the wafer was measured using ST5000 (Spectra Thick 5000ST, K-MAC). The results are shown in Table 20 below.

[0263] [Table 20]

[0264]

[0265] As shown in the above Table 20, when the slurry composition of the example was used, the silicon oxide film removal speed was about 6 times or more than that of the slurry compositions of Comparative Example 1 and Comparative Example 3. This is because the cerium oxide particles contained in the slurry composition of the example have a small particle size, and thus, the number of particles effective for polishing is large with respect to the content, and the content (molar ratio and / or weight ratio) of Ce 3+ on the surface is high, and thus, the chemical reactivity with the surface of the silicon oxide film is improved.

[0266] Experimental Example 20: Defect Evaluation of Cerium Oxide Particles

[0267] Figure 45 and Figure 46 are images of scanning before and after CMP of the oxide wafer using the CMP slurry composition containing cerium oxide particles of an embodiment of the present application and the CMP slurry composition containing cerium oxide particles of 60 nm in size.

[0268] The surface analysis of the oxide wafer was performed in a full wafer scan mode using an AIT-XP device.

[0269] Referring to Figure 45 and Figure 46, the results of analysis of the surface of the oxide wafer before and after CMP using the CMP slurry composition containing the cerium oxide particles of the embodiment of the present application, the number of defects before CMP was 6 and the number of defects after CMP was 1, and thus, the defects on the surface of the oxide wafer were reduced after CMP using the embodiment of the present application, and in addition, no scratch was generated on the surface of the wafer in the CMP process. In contrast, the results of analysis of the surface of the oxide wafer before and after CMP using the CMP slurry composition containing the conventional cerium oxide particles, the number of defects after CMP was increased to 64 compared to the number of defects before CMP which was 34, and thus, it was found that the conventional cerium oxide particles left a scratch on the surface of the wafer. This indicates that since the cerium oxide particles of the embodiment of the present application have a smaller particle size than the conventional cerium oxide particles, the probability of defects being generated on the surface of the oxide wafer as a polishing target can be significantly reduced.

[0270] Experimental Example 21: Oxide film polishing rate behavior and oxide film / polysilicon film polishing selectivity analysis with addition of cationic polymer

[0271] The cerium oxide particles according to the embodiment of the present application and the conventional commercially available 60 nm grade cerium oxide particles were added to deionized water and the pH was adjusted to 5.8, and then a cationic polymer was added as shown in Table 21 below, and the oxide film (Oxide) polishing rate and the polysilicon film polishing rate were measured under the same polishing conditions as in Experimental Example 19

[0272] [Table 21]

[0273]

[0274]

[0275]

[0276] Referring to Table 21, according to the results of addition of 0.01 wt% of the cationic polymer to the slurry using the commercially available 60 nm grade cerium oxide particles of Comparative Examples 2 to 8, the oxide film polishing rate was significantly reduced. In contrast, the slurry containing the cerium oxide particles of the present application, as shown in the results of Examples 2 to 8 in Table 21, the oxide film polishing rate was improved when the cationic polymer was contained. This feature never occurred in the CMP slurry using the conventional cerium oxide particles.

[0277] ​Furthermore, compared to Example 1 in Table 21, the grinding speed of the silicon oxide film in Examples 2 to 8, which contain cationic polymers, increased, while the grinding speed of the polycrystalline silicon film decreased significantly, and the grinding selectivity ratio of oxide film / polycrystalline silicon film was in the range of approximately 200 to 900, satisfying the range of less than 2000.

[0278] Furthermore, the content of cationic polymer in the examples and several comparative samples in Table 21 was gradually increased, and the oxide film grinding speed was observed. The behavior. Figure 47 The results are the results of measuring the behavior of the oxide film grinding speed as a cationic polymer is added to a CMP slurry composition containing cerium oxide particles or the like, according to an embodiment of the present invention.

[0279] Reference Figure 47 As shown in Table 21, the grinding speed of the CMP slurry of the present invention increases with the increase of the cationic polymer content. Conversely, the grinding speed of existing cerium oxide slurries gradually decreases as the concentration continues to increase to 0.001% or higher. This is because in existing wet cerium oxide slurries, the cationic polymer only acts as a pH buffer, and its addition is for particle stability. Therefore, when the cationic polymer content increases, it hinders the grinding process. In contrast, in the CMP slurry of the present invention, the cationic polymer not only acts as a particle stabilizer but also as a grinding accelerator.

[0280] Implementation

[0281] The present invention will now be described in more detail. However, the present invention can be implemented in many different forms, and is not limited to the embodiments described herein. The present invention is defined by the appended claims.

[0282] Furthermore, the terminology used in this invention is for illustrative purposes only and is not intended to limit the invention. Unless clearly stated otherwise, singular expressions include plural expressions. Unless expressly stated to the contrary, the use of the word "comprising" in the entire specification of this invention does not exclude other constituent elements, but rather indicates that other constituent elements may be further included.

[0283] The term "monodispersible" as used in this invention refers to the phenomenon where cerium oxide particles, when dispersed in a slurry, are suppressed from agglomerating into secondary particles, thereby relatively maintaining the primary particle size. This means that the secondary particle size (D50) measured by dynamic light scattering (DLS) is 3.0 times or less, 2.8 times or less, 2.5 times or less, 2.2 times or less, or preferably 1.9 times or less, of the primary particle size measured by TEM. Furthermore, when studying particle size distribution, the presence of unavoidable impurities with relatively large sizes is not excluded.

[0284] The term "transparent" used in the present application means that the slurry composition is transparent as observed with the naked eye when ceria particles are dispersed in the slurry, more specifically, the average light transmittance for light in the visible light region is 50% or more, preferably 70% or more, more preferably 80% or more, which further indicates that the ceria particles of the present application are inhibited from agglomerating into secondary particles, thereby relatively maintaining the primary particle diameter.

[0285] A polishing composition can be described in terms of its polishing speed (i.e., removal rate) and its planarization efficiency. Polishing speed refers to the rate at which material is removed from the surface of a substrate, typically expressed in units of length (thickness) per unit of time (e.g., angstroms per minute). Specifically, for example, a polishing pad first contacts the "high spots" of a polishing surface and removes material to form a planar surface. A process that achieves a planar surface in a manner that removes less material is more efficient than a process that requires more material to be removed in order to achieve planarity. / minute) units. Specifically, for example, a polishing pad first contacts the "high spots" of a polishing surface and removes material to form a planar surface. A process that achieves a planar surface in a manner that removes less material is more efficient than a process that requires more material to be removed in order to achieve planarity.

[0286] The removal rate of the silicon oxide pattern tends to limit the speed of the dielectric polishing step in the STI process, and thus, a higher removal rate of the silicon oxide pattern is advantageous for increasing the throughput of the apparatus. However, when the overburden removal rate is too fast, the trench is etched due to overpolishing of the oxide at the exposed trench, and the device defects are increased.

[0287] Hereinafter, the present application will be described in detail.

[0288] A first embodiment of the present application provides ceria particles for chemical mechanical polishing, which have a light transmittance of 50% or more for light having a wavelength of 500 nm in a water dispersion liquid in which the content of the ceria particles is adjusted to 1.0% by weight.

[0289] Hereinafter, the ceria particles for chemical mechanical polishing of an embodiment of the present application will be described in detail.

[0290] Figure 1 is a diagram showing the oxide film removal mechanism of an embodiment of the present application. As shown in Figure 1 Ce4+ions on the surface of the ceria particles are activated to smoothly react with SiO2. 3+

[0291] ​In one embodiment of the present application, the cerium oxide particles can be measured for particle size (primary particles) using X-ray diffraction (XRD) analysis. In one embodiment of the present application, the cerium oxide particles measured using X-ray diffraction (XRD) analysis can have a particle size of 11 nm or less. In another embodiment, it can be 10.8 nm or less, 10.5 nm or less, 10.2 nm or less, 10 nm or less, 9.5 nm or less, 9.0 nm or less, 8.5 nm or less, 8.0 nm or less, 7.5 nm or less, 7.0 nm or less, 6.5 nm or less, 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, 4.5 nm or less, or 4.0 nm or less, and it can be 0.3 nm or more, 0.5 nm or more, 0.7 nm or more, 1.0 nm or more, 1.1 nm or more, 1.2 nm or more, 1.3 nm or more, 1.4 nm or more, 1.5 nm or more, 1.6 nm or more, 1.7 nm or more, 1.8 nm or more, 1.9 nm or more, 2.0 nm or more, 2.1 nm or more, 2.2 nm or more, 2.3 nm or more, or 2.4 nm or more. When the particle size of the cerium oxide particles is less than 0.3 nm, the crystallinity is reduced, and the polishing rate for the object film is excessively hindered, thereby resulting in a decrease in polishing efficiency, and, on the contrary, when it is greater than 11 nm, there is a risk of a large number of surface defects such as scratches. In addition, in one embodiment of the present application, the cerium oxide particles measured using the X-ray diffraction (XRD) analysis can have an average particle size of 0.5 to 10 nm, preferably 1 to 10 nm, and more preferably 2 to 9 nm.

[0292] In another embodiment of the present application, the particle diameter (primary particle) of the cerium oxide particles can be measured using a transmission electron microscope (TEM). In one embodiment of the present application, the particle diameter of the cerium oxide particles measured using a transmission electron microscope (TEM) can be 11 nm or less. In another embodiment, it can be 10.8 nm or less, 10.5 nm or less, 10.2 nm or less, 10 nm or less, 9.5 nm or less, 9.0 nm or less, 8.5 nm or less, 8.0 nm or less, 7.5 nm or less, 7.0 nm or less, 6.5 nm or less, 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, 4.5 nm or less, or 4.0 nm or less, and can be 0.3 nm or more, 0.5 nm or more, 0.7 nm or more, 1.0 nm or more, 1.1 nm or more, 1.2 nm or more, 1.3 nm or more, 1.4 nm or more, 1.5 nm or more, 1.6 nm or more, 1.7 nm or more, 1.8 nm or more, 1.9 nm or more, 2.0 nm or more, 2.1 nm or more, 2.2 nm or more, 2.3 nm or more, or 2.4 nm or more. When the particle diameter of the cerium oxide particles is less than 0.3 nm, the crystallinity is reduced, and the polishing rate for the object film is excessively hindered, resulting in a decrease in the polishing efficiency, and, on the contrary, when it is greater than 11 nm, there is a risk that a large number of surface defects such as scratches are generated. In addition, in one embodiment of the present application, the average particle diameter of the cerium oxide particles measured using the transmission electron microscope (TEM) can be 0.5 to 10 nm, preferably 1 to 10 nm, and more preferably 2 to 9 nm.

[0293] In another embodiment of the present application, the particle diameter (primary particle) of the cerium oxide particles can be measured using a small angle X-ray scattering method (SAXS). In one embodiment of the present application, the particle diameter of the cerium oxide particles measured using the small angle X-ray scattering method (SAXS) can be 15 nm or less. In another embodiment, it can be 14 nm or less, 13 nm or less, 12 nm or less, 11 nm or less, 10 nm or less, 9.5 nm or less, 9.0 nm or less, 8.5 nm or less, 8.0 nm or less, 7.5 nm or less, 7.0 nm or less, 6.5 nm or less, 6.0 nm or less, 5.5 nm or less, 5.0 nm or less, 4.5 nm or less, or 4.0 nm or less, and can be 0.3 nm or more, 0.5 nm or more, 0.7 nm or more, 1.0 nm or more, 1.1 nm or more, 1.2 nm or more, 1.3 nm or more, 1.4 nm or more, 1.5 nm or more, 1.6 nm or more, 1.7 nm or more, 1.8 nm or more, 1.9 nm or more, 2.0 nm or more, 2.1 nm or more, 2.2 nm or more, 2.3 nm or more, or 2.4 nm or more. When the particle diameter of the cerium oxide particles is less than 0.3 nm, the crystallinity is reduced, and the polishing rate for the object film is excessively hindered, thereby resulting in a decrease in polishing efficiency, and, on the contrary, when it is greater than 15 nm, there is a risk that a large number of surface defects such as scratches are generated. In addition, in one embodiment of the present application, the average particle diameter of the cerium oxide particles measured using the small angle X-ray scattering method (SAXS) can be 0.5 to 15 nm, preferably 1 to 12 nm, and more preferably 1.5 to 10 nm.

[0294] In one embodiment of the present application, the particle diameter (secondary particle) in the slurry of the cerium oxide particles can be measured using dynamic light scattering (DLS) analysis. The dynamic light scattering analysis can be performed by an analysis device well known to those skilled in the art, and preferably, a particle size analyzer of Anton Paar or Zetasizer Ultra of Malvem can be used for the measurement, but this is merely an example, and is not limited thereto.

[0295] In one embodiment of the present application, the cerium oxide particles can have a particle size of 1 to 30 nm as measured by a dynamic light scattering (DLS) particle size analyzer. In another embodiment of the present application, the secondary particle size can be 29 nm or less, 27 nm or less, 25 nm or less, 23 nm or less, 22 nm or less, 20.8 nm or less, 20.5 nm or less, 20.2 nm or less, 20 nm or less, 19.8 nm or less, 19.5 nm or less, 19.2 nm or less, 18 nm or less, 17 nm or less, or 15 nm or less, and can be 1.2 nm or more, 1.4 nm or more, 1.5 nm or more, 1.8 nm or more, 2 nm or more, 3 nm or more, or 4 nm or more. When the secondary particle size is greater than the range, it indicates that a large amount of primary particles are agglomerated in the slurry composition, in which case it is difficult to consider the slurry as monodispersed. When the secondary particle size is less than the range, the polishing rate for the target film is excessively hindered, thereby resulting in a decrease in polishing efficiency.

[0296] In one embodiment of the present application, the particle size of the cerium oxide particles as measured by a dynamic light scattering (DLS) particle size analyzer is denoted as a, and the particle size of the cerium oxide particles as measured by a transmission electron microscope (TEM) is denoted as b, in which case the cerium oxide particles can satisfy Equation 2 below.

[0297] [Equation 2]

[0298] a ≤ 2.2b

[0299] This characteristic can be used as an index for indicating that the cerium oxide particles of the present application have low agglomeration when dispersed in a slurry. When the coefficient of b is greater than 2.2, it indicates that a large amount of agglomeration occurs in the slurry, which means that it is difficult to suppress wafer surface defects when polishing due to the particle size becoming coarse.

[0300] In another embodiment of the present application, the particle size of the cerium oxide particles as measured by a dynamic light scattering (DLS) particle size analyzer is denoted as a, and the particle size of the cerium oxide particles as measured by a small angle X-ray scattering (SAXS) is denoted as b, in which case the cerium oxide particles can satisfy Equation 3 below.

[0301] [Equation 3]

[0302] a ≤ 2.5b

[0303] This characteristic can be used as an index for indicating that the cerium oxide particles of the present application have low agglomeration when dispersed in a slurry. When the coefficient of b is greater than 2.5, it indicates that a large amount of agglomeration occurs in the slurry, which means that it is difficult to suppress wafer surface defects when polishing due to the particle size becoming coarse.

[0304] In one embodiment of the present application, the Ce content of the surface of the ceria particles can be analyzed using XPS. For example, a theta probe base system manufactured by Thermo Fisher Scientific Co. can be used. The Ce content of the surface of the ceria abrasive particles can be calculated based on the following Chemical Formula 1. 3+ [Chemical Formula 1] 3+

[0305] [Chemical Formula 1]

[0306] Ce 3+ content (%) = (Ce 3+ peak area) / [(Ce 3+ peak area) + (Ce 4+ peak area)]

[0307] In one embodiment, when X-ray photoelectron spectroscopy (XPS) analysis is performed on the surface of the ceria particles, XPS peaks representing Ce-O binding energy of Ce 3+ occur at 900.2-902.2 eV, 896.4-898.4 eV, 885.3-887.3 eV, and 880.1-882.1 eV. Specifically, when X-ray photoelectron spectroscopy (XPS) analysis is performed on the surface of the ceria particles, XPS peaks representing Ce-O binding energy of Ce 3+ occur at 900.2-902.2 eV, 896.4-898.4 eV, 885.3-887.3 eV, and 880.1-882.1 eV. Specifically, when X-ray photoelectron spectroscopy (XPS) analysis is performed on the surface of the ceria particles, XPS peaks representing Ce-O binding energy of Ce

[0308] In one embodiment of the present application, based on the total area of the XPS peaks, the area of the first peak can be 3% or more or 4% or more, the areas of the second and fourth peaks can be 5% or more, 7% or more, or 10% or more, respectively, and the area of the third peak can be 4% or more, 5% or more, or 6% or more.

[0309] In addition, in one embodiment of the present application, when X-ray photoelectron spectroscopy (XPS) analysis is performed, the ratio of the sum of the areas of XPS peaks representing Ce-O binding energy of Ce 3+ may be 0.29-0.70. In another embodiment of the present application, the ratio of the sum of the areas of XPS peaks representing Ce-O binding energy of Ce 3+ ​The ratio of the sum of the XPS peak areas at the Ce-O binding energy of the CeO2 particle to the total sum of the XPS peak areas at the Ce-O binding energy of the surface of the cerium oxide particle can be 0.18 or more, 0.19 or more, 0.192 or more, 0.195 or more, 0.198 or more, 0.20 or more, 0.202 or more, 0.205 or more, 0.208 or more, 0.21 or more, 0.22 or more, 0.24 or more, 0.25 or more, 0.27 or more, 0.28 or more, 0.30 or more, 0.32 or more, or 0.35 or more, and can be 0.90 or less, 0.88 or less, 0.85 or less, 0.83 or less, 0.80 or less, 0.77 or less, 0.75 or less, 0.72 or less, 0.71 or less, 0.705 or less, 0.70 or less, 0.695 or less, 0.69 or less, 0.68 or less, 0.67 or less, 0.66 or less, 0.65 or less, 0.64 or less, 0.63 or less, 0.62 or less, 0.61 or less, or 0.60 or less. When less than the above range, the CeO2 particle surface cannot have a sufficient amount of Ce 3+ Thus, it is difficult to expect a sufficient increase in the polishing rate of the oxide film, and when more than the above range, it is difficult to explain as being present in the form of a cerium oxide particle in view of the oxidation number.

[0310] That is, in one embodiment of the present application, when X-ray photoelectron spectroscopy (XPS) analysis is performed, the surface of the cerium oxide particle for chemical mechanical polishing has a Ce 3+ content of 18 atomic % or more, 19 atomic % or more, 20 atomic % or more, 22 atomic % or more, 24 atomic % or more, 25 atomic % or more, 27 atomic % or more, 28 atomic % or more, 30 atomic % or more, 32 atomic % or more, or 35 atomic % or more, and can be 90 atomic % or less, 88 atomic % or less, 85 atomic % or less, 83 atomic % or less, 80 atomic % or less, 77 atomic % or less, 75 atomic % or less, 72 atomic % or less, or 70 atomic % or less.

[0311] The cerium oxide particle of one embodiment of the present application has a Ce 3+ content of the surface of the particle is relatively high, the polishing rate of the oxide film can be improved. 3+

[0312] In one embodiment of the present application, the cerium oxide particle of one embodiment of the present application exhibits a Raman spectral characteristic for distinguishing it from existing polishing particles, suggesting that the particle surface contains a large amount of Ce 3+ component. Specifically, the cerium oxide particle can have two or more Raman peaks in a Raman spectrum. ​

[0313] In one embodiment of the present application, the ceria particles can have a first Raman peak in a spectral band range of 455 cm -1 -460 cm -1 In another embodiment, the ceria particles can have a second Raman peak in a spectral band range of 586 cm -1 -627 cm -1 In another embodiment, the ceria particles can have a third Raman peak in a spectral band range of 712 cm -1 -772 cm -1 The spectral band range can represent a range of Raman shift values as an X-axis of a Raman spectrum.

[0314] In one embodiment of the present application, the ratio A / B of the first Raman peak intensity A to the second Raman peak intensity B of the ceria particles can be 35 or less. The A / B is preferably 30 or less, more preferably 25 or less, and even more preferably 20 or less. The lower limit of the A / B is not particularly limited and can be 5 or more, 10 or more, or 15 or more. The second Raman peak can be interpreted as a Raman shift occurring as the proportion of oxygen vacancies increases as the content of Ce 3+ increases, and thus, the smaller the intensity ratio A / B, the greater the content of Ce 3+ in the ceria particles, which implies that the chemical polishing action using the Si-O-Ce bond of the oxide film wafer can be promoted, and thus, the polishing rate can be increased even though the ceria particles are smaller than conventional ceria particles.

[0315] In one embodiment of the present application, the ratio A / C of the first Raman peak intensity A to the third Raman peak intensity C of the ceria particles can be 50 or less. The A / C is preferably 45 or less, and more preferably 43 or less. The lower limit of the A / C is not particularly limited and can be 5 or more, 10 or more, or 15 or more.

[0316] As described above, the ceria particles of one embodiment of the present application contain a high content of Ce 3+ compared to conventional ceria particles, and thus, a slurry composition having an excellent polishing rate with respect to the content of ceria particles can be provided even though the ceria particles are small, and the generation of polishing scratches can be controlled.

[0317] In one embodiment of the present application, the content of Ce 3+ on the surface of the ceria particles can be analyzed using electron energy loss spectroscopy (EELS), for example, a value of 2 or more representing Ce 4+EELS peak representing the oxidation state.

[0318] The cerium oxide particles (and / or the slurry composition containing the same) can have an EELS spectrum as shown in Figures 23 to 25

[0319] The EELS spectrum of the cerium oxide particles of an embodiment of the present application can include a first peak at 876.5 to 886.5 eV and a second peak at 894.5 to 904.5 eV, and the maximum intensity of the first peak can be greater than that of the second peak. Such a pattern can represent the Ce 3+ The higher the content of Ce

[0320] In an embodiment of the present application, the spectrum can further include a third peak at 886.5 to 889.5 eV and a fourth peak at 904.5 to 908.5 eV. The third and fourth peaks can be used to distinguish peaks based on the oxidation state, and the cerium oxide particles of the present application can be distinguished from the conventional cerium oxide particles by calculating the areas of the peak intervals that occur based on the oxidation state of Ce 4+

[0321] In addition, in an embodiment of the present application, the sum of the areas of the third peak intervals P1 and the sum of the areas of the peaks of the spectrum P t t may be 0.025 or less, preferably 0.024 or less, 0.022 or less, 0.018 or less, 0.015 or less, 0.012 or less, 0.011 or less, or 0.01 or less. In contrast, the minimum value of the conventional cerium oxide particles is 0.03 or more, and such a feature can be embodied by the following experimental example.

[0322] In an embodiment of the present application, the sum of the areas of the third peak intervals P1 and the sum of the areas of the fourth peak intervals P2 with respect to the sum of the areas of the peaks of the spectrum P t t may be 0.1 or less. In addition, the area ratio is preferably 0.099 or less, 0.098 or less, 0.096 or less, 0.095 or less, 0.094 or less, 0.092 or less, or 0.090 or less. The ratio of the cerium oxide particles of an embodiment of the present application can represent, for example, the average ratio of values measured n times when the same sample is measured n times. In other examples, the area ratio (P1+P2) / P t ​​​​It can be 0.01 or higher, 0.012 or higher, 0.014 or higher, 0.016 or higher, or 0.018 or higher. When the area ratio is less than 0.1, it can represent the Ce content compared to the total cerium oxide content on the surface of the cerium oxide particles. 3+ High content, and higher Ce content. 3+ The content can promote the chemical polishing effect on silicon oxide film through Si-O-Ce bonds, thereby improving the polishing rate.

[0323] One embodiment of the present invention produces cerium oxide particles exhibiting X-ray absorption fine structure (XAFS) spectral features that distinguish them from existing abrasive particles, suggesting that the particle surface contains a large amount of Ce. 3+ Components. Specifically, the cerium oxide particles may have more than two peaks in the XAFS spectrum.

[0324] In one embodiment of the invention, the cerium oxide particles (and / or the slurry composition comprising them) may have the following characteristics: Figure 33 and Figure 34 The XAFS spectrum shown is shown in the figure.

[0325] In one implementation example, during XAFS spectral measurements, the cerium oxide particles exhibit a maximum absorption coefficient with a first peak in the range of 5730 eV or greater and less than 5740 eV, where the first peak represents Ce. 3+ The oxidation state.

[0326] In another implementation, during XAFS spectral measurements, the cerium oxide particles exhibit a maximum absorption coefficient with a second peak in the range of 5740 eV or greater and less than 5760 eV, where the second peak may represent Ce. 4+ The oxidation state.

[0327] In one embodiment of the present invention, the maximum absorption coefficient (maximum value of the peak) of the first peak may be 0.1 to 0.4. In another embodiment of the present invention, the maximum absorption coefficient of the first peak may be 0.11 or higher, 0.12 or higher, 0.13 or higher, 0.14 or higher, 0.15 or higher, 0.2 or higher, or 0.25 or higher, and may be 0.38 or lower, 0.35 or lower, 0.32 or lower, or 0.30 or lower.

[0328] In one embodiment of the present application, the maximum absorbance of the second peak (the maximum value of the peak) can be less than 0.6. In another embodiment of the present application, the maximum absorbance of the second peak can be 0.11 or more, 0.12 or more, 0.13 or more, 0.14 or more, 0.15 or more, 0.2 or more, or 0.25 or more, and can be 0.58 or less, 0.55 or less, 0.52 or less, or 0.50 or less.

[0329] When the absorbance of the first peak is less than 0.1 and the absorbance of the second peak is greater than 0.6, it means that the amount of Ce 3+ is less than the total weight of the surface of the cerium oxide, which can further indicate that the polishing rate is hindered.

[0330] In one embodiment of the present application, the ratio A1 / A2 of the area A1 of the first peak to the area A2 of the second peak in the XAFS spectrum can be 0.03 or more. The ratio of the areas of the peaks A1 / A2 can be 0.03 or more, 0.05 or more, 0.07 or more, 0.09 or more, or 0.1 or more, more preferably 0.11 or more, and even more preferably 0.12 or more. That is, the ratio A3 / (A3+A4) of the area A3 of the peak representing Ce 3+ in the XAFS spectrum to the sum of the area A3 of the peak representing Ce 3+ in the XAFS spectrum to the area A4 of the peak representing Ce 4+ in the XAFS spectrum can be 0.1 or more (10% or more). When the ratio of the areas is less than 0.03, the amount of Ce 4+ is less than the amount of Ce 3+ on the surface of the cerium oxide particles, and thus there is a risk that the polishing rate is hindered.

[0331] In an implementation example of the present application, the cerium oxide particles can be subjected to photoelectron spectroscopy analysis, specifically ultraviolet photoelectron spectroscopy (UPS) analysis using light in the UV band. Photoelectron spectroscopy techniques can be divided into existing X-ray photoelectron spectroscopy (XPS) using light in the X-ray band of a single wavelength and ultraviolet photoelectron spectroscopy (UPS) using light in the UV band. XPS is a technique using X-rays having an energy of about 1000-1500 eV and mainly analyzing electrons released from the core level of atoms inside a sample to obtain the kind, chemical state, concentration, etc. of elements in the sample, and there are a large number of commercial devices being sold, and the analysis method and use method, etc. are widely known, while UPS is a technique using light in the extreme UV band of about 10-20 eV to release electrons in the valence electron region of a sample to obtain the various states that electrons directly participating in chemical bonding can have inside a solid. In particular, so-called angle-resolved ultraviolet photoelectron spectroscopy (ARUPS / ARPES) can directly measure the band structure of a single-crystal sample, and therefore, this measurement can be used to study the physical properties of high-temperature superconductors and giant magnetoresistance materials, etc. that are important factors in understanding the special properties of matter. When light having an energy of hv is irradiated to a solid sample, according to the law of conservation of energy and momentum, the electron acquires kinetic energy. At this time, the value of the kinetic energy of the electron emitted from the sample is as follows.

[0332] E kin = hv - φ - |E b |

[0333] where E kin is the kinetic energy of the emitted electron, φ is the work function of the sample, and E b is the binding energy of the emitted electron when bound by the sample. By measuring the intensity of the kinetic energy of the emitted electron from the outside using an electron energy analyzer, the density of states based on the binding energy of the electron inside the sample can be obtained. Therefore, referring to the above equation, the binding energy can be derived from the measured kinetic energy, at which time, the work function φ of the sample can be expressed using the value of the source energy hv, the Fermi level E F , and the vacuum level E cutoff .

[0334] φ = hv - |E f - E cutoff |

[0335] When the UPS result value is shown on a graph, zero of the x axis indicates Fermi energy level EF of the sample, E cutoff is a value shown based on a vacuum level. hv is used as a source energy at the time of emitting ultraviolet rays, indicating the energy of incident light, and helium (He) is generally used as the source.

[0336] In one embodiment of the present application, the band structure of the cerium oxide varies depending on the particle diameter of the particles, and the smaller the particle diameter of the particles, the larger the energy level difference between the plurality of orbits of the sample, and thus, the larger the energy band gap. Conversely, the larger the particle diameter of the particles, the smaller the energy level difference, and thus, the smaller the energy band gap. Therefore, as described above, the smaller the particle diameter of the particles, the larger the energy gap between the valence band and the conduction band, and the values of the Fermi energy level EF and the vacuum level change, and thus, the energy (eV) of the derived work function is larger.

[0337] In one embodiment of the present application, the maximum value of the number of photoelectrons released per second (Counts) of the cerium oxide particles can exist in a range of kinetic energy of 10 eV or less when UPS analysis is performed. This characteristic is a characteristic that is distinguished from existing cerium oxide particles. The maximum value of the number of photoelectrons released per second (Counts) can exist in a range of kinetic energy of 6 to 10 eV, or 7 to 10 eV, and preferably 8 to 10 eV.

[0338] In one embodiment of the present application, the work function value measured by UPS of the cerium oxide particles can be 2.5 eV or more. The work function value is preferably 2.7 eV or more, and more preferably 3.0 eV or more. The upper limit of the work function value is not particularly limited, and can be less than 10 eV, 9 eV or less, or 8 eV or less. The work function value satisfying the above range is a characteristic that is distinguished from existing cerium oxide particles, and indicates that the particle diameter of the cerium oxide particles dispersed in the slurry is small, which means that the coaggregation is very weak. Since the cerium oxide particles of one embodiment of the present application have such a low coaggregation and monodisperse characteristic, when used in a manner of being contained in a slurry for chemical mechanical polishing, the number of particles in contact with a wafer can be maximized, and while the polishing rate of the oxide film is improved, the particle diameter itself becomes small, and thus, the defects on the surface of the wafer can be minimized.

[0339] In one embodiment of the present application, when the specific surface area of 1 g of the powder composed of the cerium oxide particles is measured, the BET specific surface area value can be 50 m 2 / g or less. In another embodiment, the BET specific surface area value can be 49 m 2 / g or less, 48 m 2 / g or less, 47 m 2 / g or less, 46 m 2 / g or less, 45 m 2 / g or less, 44 m 2 / g or less, 43 m 2 / g or less, more preferably 42 m 2 / g or less. It exhibits a different tendency from the existing cerium oxide particles in which the BET specific surface area value increases as the particle diameter decreases, because the cerium oxide particles synthesized by a self-organizing synthesis method such as a sol-gel method, a bottom-up method, etc. have a smaller specific surface area and pore volume compared to the cerium oxide particles made by other synthesis methods, and in particular, the proportion of -OH functional groups on the surface of the cerium oxide particles is low. In addition, it can be predicted that the cerium oxide particles have a more minute particle diameter compared to the existing cerium oxide particles, and the result of analyzing the powder sample using BET under the same conditions as the 1.0 g of powder is that the density of the powder sample is higher than that of the existing cerium oxide particles of Comparative Example 1, and the BET specific surface area value is smaller. Therefore, it can be confirmed that the cerium oxide particles of the embodiment of the present application have a smaller particle diameter compared to the existing 10 nm-level cerium oxide particles of Comparative Example 1, but have a smaller BET specific surface area value than the cerium oxide particles of Comparative Example 1, and this result can be in the same vein as the tendency that the cerium oxide particles of the embodiment of the present application exhibit a higher content of Ce 3+ content than the existing cerium oxide particles. 4+ and a higher content of -OH functional groups on the surface.

[0340] In an embodiment of the present application, the apparent density of the cerium oxide particles measured based on the tap method can be 2.00 to 5.00 g / mL, preferably 2.00 to 4.00 g / mL, and more preferably 2.00 to 3.00 g / mL.

[0341] In another embodiment of the present application, the apparent density of the cerium oxide particles measured based on the tap method can be 2.90 to 5.00 g / mL, preferably 3.00 to 5.00 g / mL, and more preferably 3.20 to 5.00 g / mL.

[0342] When the slurry of the cerium oxide particles having an apparent density of more than 5.00 g / mL dispersed in water is used for polishing, scratches can be generated on the polishing surface due to the coarse primary particle diameter and secondary particle diameter. In addition, in an embodiment of the present application, when cerium oxide particles of less than 2.00 g / mL are used, the polishing rate is sharply reduced as the primary particle diameter decreases, and thus sufficient polishing effects cannot be obtained, and thus it is preferable that even smaller particles of less than 10 nm have an apparent density of more than 2.00 g / mL. Thus, the cerium oxide particles of an embodiment of the present application have a relatively higher apparent density compared to conventional cerium oxide particles, and thus differ from the conventional cerium oxide particles. This characteristic can also have an effect on the polishing rate of the oxide film.

[0343] In an embodiment of the present application, based on a water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0 wt%, when the photoluminescence (PL) intensity is measured at a wavelength of 325 nm, the maximum intensity of the first peak λ1 at a wavelength of 435 to 465 nm can be in the range of 0.1 to 30, 0.2 to 20, 0.3 to 10, or 0.5 to 7. The maximum peak intensity of conventional commercially available coarse cerium oxide particles is more than 30 under the same conditions, which can indicate that the aggregation in the slurry is strong, and thus the luminescence is stronger than the transmittance.

[0344] In an embodiment of the present application, based on a water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0 wt%, the maximum intensity of the second peak λ2 at a wavelength of 510 to 540 nm can be in the range of 0.1 to 10, 0.1 to 7.5, 0.1 to 5, or 0.1 to 3. The maximum peak intensity of conventional commercially available coarse cerium oxide particles is more than 10 under the same conditions, which can indicate that the aggregation in the slurry is strong, and thus the luminescence is stronger than the transmittance.

[0345] In an embodiment of the present application, for a water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0 wt%, the photoluminescence (PL) intensity can be measured at a wavelength of 325 nm to obtain the characteristics of the particles. Specifically, in an embodiment of the present application, when a fluorescence spectrometer analysis is performed using an excitation wavelength of 325 nm, an excitation peak λ exc a first peak λ1 at a wavelength of 435 to 465 nm, and a second peak λ2 at a wavelength of 510 to 540 nm. The excitation peak can be interpreted as a peak indicating the excitation wavelength, the first peak represents Ce 3+ , and the second peak represents Ce 4+ .

[0346] In one embodiment of the present application, for the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when the photoluminescence (PL) intensity is measured at a wavelength of 325 nm, the intensity ratio λ1 / λ exc of the first peak λ1 at a wavelength of 435 to 465 nm to the excitation peak λ exc may be less than 30, preferably 27 or less, 25 or less, more preferably 23 or less, 20 or less, even more preferably 18 or less, further preferably 15 or less, and still further preferably 10 or less.

[0347] In one embodiment of the present application, the intensity ratio λ1 / λ2 of the first peak λ1 to the second peak λ2 at a wavelength of 510 to 540 nm can be 4 or more, preferably 5 or more, more preferably 5.5 or more, and even more preferably 6 or more, and can be 20 or less, preferably 18 or less, more preferably 15 or less, even more preferably 12 or less, and further preferably 10 or less.

[0348] The intensity ratio λ1 / λ exc of the first peak λ1 to the excitation peak λ exc and the intensity ratio λ1 / λ2 of the first peak λ1 to the second peak λ2 of the cerium oxide particles of one embodiment of the present application satisfy the above ranges, and therefore the surface of the cerium oxide particles contains a high content of Ce 3+ , and at the same time, the dispersion liquid is rarely aggregated into secondary particles, thereby having a good light transmittance while having the characteristic of a relatively high Ce 3+ content on the surface of the particles. When the cerium oxide particles of the present application are used for a slurry for chemical mechanical polishing, the Ce 3+ content on the surface of the particles is high, and the particles themselves are small, and have the characteristic of rarely being aggregated in the slurry, and therefore the chemical polishing rate based on the Si-O-Ce bond between the cerium oxide particles and the oxide film substrate is increased, thereby increasing the oxide film polishing rate.

[0349] In one embodiment of the present application, the yellow degree of the dispersion liquid containing the cerium oxide particles can be evaluated using the L*a*b* color system, where the definition of L*a*b is the CIE1976 L*a*b* color space specified by the Commission Internationale de Eclairage (CIE) in 1976. This color space is a color space including L*, a*, and b* defined by the following formula in a rectangular coordinate system.

[0350] L* = 116 (Y / Y0) 1 / 3 - 16

[0351] a* = 500 [(X / X0) 1 / 3 -(Y / Y0) 1 / 3 ]

[0352] b* = 200 [(Y / Y0) 1 / 3 -(Z / Z0) 1 / 3 ]

[0353] wherein X / X0, Y / Y0, Z / Z0 > 0.008856, X, Y, Z are three stimulus values of the color of the object, and X0, Y0, Z0 are three stimulus values of the light source which illuminates the color of the object, with Y0 = 100 as a standard.

[0354] L* represents luminance, also called "luminance index". In addition, a* and b* represent color and chroma, also called "Chromaticness index". In the L*a*b* color system, the larger the L* value, the closer the color to white, and the smaller the L* value, the closer the color to black. Furthermore, as the a* value increases toward the + direction, the color of the red series becomes stronger, and as the a* value decreases (increases toward the - direction), the color of the green series becomes stronger. In addition, as the b* value increases toward the + direction, the color of the yellow series becomes stronger, and as the b* value decreases (increases toward the - direction), the color of the blue series becomes stronger. In addition, when both a* value and b* value are 0, it indicates achromatic color.

[0355] In one embodiment of the present application, when the color of the water dispersion in which the content of the cerium oxide particles is adjusted to 1.0% by weight is expressed using the L*a*b* color system, the L* value can be 80 or more, preferably 85 or more, more preferably 90 or more, even more preferably 95 or more, and further preferably 98 or more. When the L* value is less than the range, it indicates that the cerium oxide abrasive particles are in a state of excessive growth, and indicates that there are many large particles that cause defects in the wafer during polishing. In addition, the L* value can be 100 or less, preferably 99.9 or less.

[0356] In one embodiment of the present application, the b* value can be 8 or more, preferably 10 or more, and more preferably 11 or more, and can be in a range of less than 30, preferably 25 or less, more preferably 20 or less, and further preferably 15 or less. When the b* value is less than the range, the chemical reaction required during polishing cannot be obtained, and the small irregularities on the polishing surface cannot be polished smooth.

[0357] In one embodiment of the present application, the a* value can be in a range of less than -3, preferably -4 or less, and more preferably -5 or less, and can be -8 or more, and more preferably -7 or more.

[0358] Therefore, when the color of the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight is expressed by the L*a*b* color system, if each value is within the above range, it is observed that the dispersion liquid is in a yellow transparent state, and the deeper the yellow color of the dispersion liquid, the faster the polishing speed. In particular, the cerium oxide particles of an embodiment of the present application, although minute in particle size, when contained in a slurry for chemical mechanical polishing, have a high proportion of Ce 3+ on the surface of the cerium oxide particles, and thus can significantly improve the polishing speed of the oxide film, and the minute particles can minimize defects on the surface of a wafer, and if each value is within the range, or in particular, has a higher yellow index when expressed by the L*a*b* color system, it indicates that the proportion of Ce 3+ on the surface of the cerium oxide particles is in a relatively very high state compared to conventional cerium oxide particles.

[0359] In an embodiment of the present application, for the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when centrifugal separation is performed for 30 minutes at a centrifugal force of 4265 G (6,000 rpm), the settling rate of the cerium oxide particles can be 25% by weight or less. In another embodiment, the settling rate can be 20% by weight or less, 15% by weight or less, 10% by weight or less, and more preferably 5% by weight or less.

[0360] In addition, in an embodiment of the present application, for the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when centrifugal separation is performed for 10 minutes at a centrifugal force of 2100 G (3,200 rpm), the settling rate of the cerium oxide particles can be 0.6% by weight or less. In another embodiment, the settling rate can be 0.55% by weight or less, 0.5% by weight or less, 0.45% by weight or less, and more preferably 0.4% by weight or less.

[0361] In addition, in another embodiment of the present application, for the water dispersion liquid in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when centrifugal separation is performed for 30 minutes at a centrifugal force of 3300 G (4,000 rpm), the settling rate of the cerium oxide particles can be 5.0% by weight or less. In another embodiment, the settling rate can be 4.8% by weight or less, 4.5% by weight or less, 4.2% by weight or less, and more preferably 4.0% by weight or less.

[0362] In another embodiment of the present application, for the aqueous dispersion in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when centrifugal separation is performed for 30 minutes at a centrifugal force of 26188 G (12,000 rpm), the sedimentation rate of the cerium oxide particles can be 45.0% by weight or less. In another embodiment, the sedimentation rate can be 42% by weight or less, 40% by weight or less, 38% by weight or less, and more preferably 35% by weight or less.

[0363] In another embodiment of the present application, for the aqueous dispersion in which the content of the cerium oxide particles is adjusted to 1.0% by weight, when centrifugal separation is performed for 30 minutes at a centrifugal force of 39282 G (18,000 rpm), the sedimentation rate of the cerium oxide particles can be 90.0% by weight or less. In another embodiment, the sedimentation rate can be 80% by weight or less, 70% by weight or less, 65% by weight or less, and more preferably 60% by weight or less.

[0364] In an embodiment of the present application, the liquid viscosity of the aqueous dispersion can be 0.3 to 2.0 mPa-s, 0.5 to 1.8 mPa-s, 0.55 to 1.5 mPa-s, or 0.6 to 1.2 mPa-s, and in a preferred embodiment, centrifugal separation can be performed at 0.65 to 1.2 mPa-s.

[0365] When centrifugal separation is performed in this manner from the weaker centrifugal force condition to the stronger centrifugal force condition, respectively, if the sedimentation rate of the cerium oxide particles is within the above range, respectively, it indicates that the cerium oxide particles of an embodiment of the present application have a more minute particle size and are monodispersed compared to conventional cerium oxide particles, and thus, since the number of contact particles increases due to the monodispersed particles contacting the wafer in the chemical mechanical polishing process, the polishing rate of the oxide film is improved, and when polishing is performed based on the minute embodiment of the present application, the polishing defect occurrence rate can be reduced.

[0366] In an embodiment of the present application, the cerium oxide primary particles can be one or more selected from the group consisting of a spherical shape, a cube shape, a tetragonal shape, an orthorhombic shape, a Rhombohedral shape, a Monoclinic shape, a hexagonal shape, a triclinic shape, and a cuboctahedron shape, and preferably a spherical particle.

[0367] In one embodiment of the present application, the cerium oxide particles can be produced by a method in which particles are grown by chemical synthesis, preferably in a bottom up manner. As the synthesis method for the cerium oxide particles, a sol-gel method, supercritical reaction, hydrothermal reaction, or a coprecipitation method, or the like can be used, but is not limited thereto. The bottom up method is one of chemical synthesis that has recently attracted attention, in which atomic or molecular starting materials are grown into nano-sized particles through chemical reactions.

[0368] In one embodiment of the present application, the polishing composition contains wet cerium oxide particles. The wet cerium oxide particles can be any suitable wet cerium oxide particles. For example, the wet cerium oxide particles can be precipitated cerium oxide particles or condensed cerium oxide particles including colloidal cerium oxide particles.

[0369] In one embodiment of the present application, the wet cerium oxide particles preferably have defects on the surface of the particles. Although not intended to be bound by any particular theory, pulverization of cerium oxide particles can cause defects on the surface of the cerium oxide particles, and such defects can affect the performance of the cerium oxide particles in the chemical mechanical polishing composition. In particular, the cerium oxide particles can be broken when pulverized, thereby exposing a relatively less favorable surface state. This process is relaxation, in which atoms around the surface of the cerium oxide particles have limited ability to reconfigure and limited ability to recover to a more favorable state, and defects are formed on the surface of the particles.

[0370] In one embodiment of the present application, when secondary particles of the polishing material are produced, the solvents each have an inherent dielectric constant value, and in nucleation and crystal growth when the powder is synthesized, the dielectric constant of the solvent changes the surface energy or surface charge, and the like, thereby affecting the aggregation and growth of the nuclei, and this affects the size and shape of the powder, and the like. The dielectric constant of the solvent is proportional to the Zeta potential of the particles dispersed in the solvent, and the smaller the Zeta potential, the smaller the surface repulsive force between the fine particles or the nuclei produced by the reaction, and thus, the fine particles or the nuclei are in an unstable state, so that the fine particles or the nuclei rapidly aggregate. At this time, the size of the surface repulsive force between the fine particles or the nuclei is similar, and thus, the fine particles or the nuclei can be aggregated in a uniform size. The secondary particles thus aggregated are produced by growing the primary fine particles or the nuclei to a larger size through a particle coalescence process such as strong aggregation or Ostwald ripening, according to the reaction conditions such as temperature, concentration, and the like.

[0371] The second embodiment of the present application provides a slurry composition for chemical mechanical polishing, which includes cerium oxide particles and a solvent, and in which the content of the cerium oxide particles is adjusted to 1.0% by weight in an aqueous dispersion, and the light transmittance for light having a wavelength of 500 nm is 50% or more.

[0372] The detailed description of the parts that are repeated with the first embodiment of the present application is omitted, but the description of the first embodiment of the present application is equally applicable to the second embodiment even if the description is omitted.

[0373] Hereinafter, the slurry composition for chemical mechanical polishing of the second embodiment of the present application is described in detail.

[0374] The slurry composition for chemical mechanical polishing of an embodiment of the present application includes cerium oxide particles and a solvent.

[0375] In an embodiment of the present application, the Zeta potential value of the cerium oxide particles included in the slurry as abrasive particles can be positive, and preferably, the Zeta potential value can be 1 to 80 mV, 5 to 60 mV, or 10 to 50 mV in the range of pH 2 to 8. The Zeta potential value of the cerium oxide particles is positive, and thus the polarity of the surface of the silicon oxide film is negative, and therefore the polishing efficiency is improved due to the attractive force between the cerium oxide particles and the surface of the silicon oxide film.

[0376] In an embodiment of the present application, the hardness of the cerium oxide particles is lower than that of silica particles or alumina particles, but the polishing speed for a surface containing silicon such as a glass or a semiconductor substrate is very fast based on a chemical polishing mechanism in which a Si-O-Ce bond is formed between silica and cerium, and thus it is advantageous for polishing of a semiconductor substrate.

[0377] In an embodiment of the present application, the content of a precursor substance in the slurry composition can be 300 ppm or less on a weight basis. In another embodiment of the present application, the content of a precursor substance in the slurry composition can be 200 ppm or less, 150 ppm or less, 100 ppm or less, 75 ppm or less, 50 ppm or less, 25 ppm or less, 15 ppm or less, 10 ppm or less, 7.5 ppm or less, 5 ppm or less, 2.5 ppm or less, 2 ppm or less, 1.75 ppm or less, 1.5 ppm or less, 1.25 ppm or less, 1 ppm or less, 0.75 ppm or less, or 0.5 ppm or less on a weight basis. In fact, the slurry composition can not include a precursor substance. The precursor substance includes a cerium precursor substance, a basic substance, a solvent, and a precursor substance used or generated in the process of manufacturing cerium oxide particles by a wet process, and the like.

[0378] In one embodiment of the present application, the content of the cerium oxide particles can be 5% by weight or less, based on the total weight of the slurry composition for chemical mechanical polishing. In another embodiment of the present application, the content of the cerium oxide particles can be 4% by weight or less, 3% by weight or less, 2% by weight or less, 1.5% by weight or less, 1% by weight or less, 0.8% by weight or less, 0.5% by weight or less, 0.4% by weight or less, 0.3% by weight or less, 0.2% by weight or less, less than 0.2% by weight, 0.19% by weight or less, 0.15% by weight or less, 0.12% by weight or less, 0.10% by weight or less, 0.09% by weight or less, or 0.07% by weight or less, and can be 0.0001% by weight or more or 0.001% by weight or more, based on the total weight of the slurry composition for chemical mechanical polishing. The slurry composition for chemical mechanical polishing of the present application can achieve a higher polishing efficiency of the oxide film even when the content of the cerium oxide particles is lower, based on the total weight of the slurry composition for chemical mechanical polishing, while using a slurry having the same polishing rate.

[0379] In one embodiment of the present application, the average light transmittance for light having a wavelength of 450 to 800 nm in the aqueous dispersion in which the content of the cerium oxide particles is adjusted to 1.0% by weight can be 50% or more or 60% or more, and the average light transmittance can preferably be 70% or more, more preferably 80% or more, and even more preferably 90% or more. In another embodiment of the present application, the light transmittance for light having a wavelength of 500 nm can be 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, 75% or more, or 80% or more. In addition, the light transmittance for light having a wavelength of 600 nm can be 75% or more, 80% or more, 85% or more, or 90% or more. In addition, the light transmittance for light having a wavelength of 700 nm can be 87% or more, 90% or more, 93% or more, or 95% or more. The fact that the value of the light transmittance of the slurry composition satisfies the above range means that the primary particle diameter of the cerium oxide particles of one embodiment of the present application is small per se, and the cerium oxide particles are less aggregated into secondary particles than conventional cerium oxide particles. When the aggregation is thus weak, the dispersion stability is high, the particles can be uniformly distributed, and the number of particles in contact with the wafer increases, and thus the polishing rate of the oxide film is excellent, and the particles are small per se, and thus the probability of defects such as scratches on the surface can be reduced when the film to be polished is polished using a slurry composition containing the particles. That is, the higher the light transmittance in the visible light region for cerium oxide particles of 10 nm or less based on the primary particles, the more excellent the polishing rate of the silicon oxide film.

[0380] In one embodiment of the present application, when a Fourier-transformation infrared (FT-IR) spectroscopy is performed on the powder composed of the cerium oxide particles, in a specific spectrum based on the FT-IR spectroscopy, the infrared transmittance of the powder composed of the cerium oxide particles can be 90% or more, or 100% or less, 97% or less, or 95% or less, in the range of 3000 cm -1 ~ 3600 cm -1 In one embodiment of the present application, in the range of 720 cm -1 ~ 770 cm -1 , the infrared transmittance of the powder can be 96% or less, and can be 85% or more, 88% or more, more preferably 90% or more, and even more preferably 92% or more. In the range of 3000 cm -1 ~ 3600 cm -1 of the FT-IR spectrum, the infrared transmittance has a value in the range, which can indicate that a band based on an O-H group is relatively weak, which is distinguished from the FT-IR spectrum of a powder composed of cerium hydroxide particles. In addition, in the range of 720 cm -1 ~ 770 cm -1 of the FT-IR spectrum of the powder composed of the cerium oxide particles according to one embodiment of the present application, there is a peak indicating the infrared transmittance of the range, which can indicate that Ce-O stretching occurs in the range, and which can indicate that the particles manufactured according to one embodiment of the present application exhibit characteristics of cerium oxide particles.

[0381] In one embodiment of the present application, the pH of the slurry composition for chemical mechanical polishing can be in the range of 10 or less, preferably in the range of 1 to 9, 1 to 8, or 2 to 7, in terms of dispersion stability and polishing efficiency. More specifically, when the pH is less than 1, the removal rate of a silicon oxide film can be sharply decreased, thereby exhibiting poor polishing characteristics, and when the pH is greater than 10, poor polishing characteristics can be exhibited, or the pH stability and dispersion stability can be decreased, causing aggregation, thereby generating micro scratches and defects.

[0382] In one embodiment of the present application, the slurry composition for chemical mechanical polishing can include one or more acidic or basic pH adjusting agents and buffers capable of adjusting the pH, in consideration of the final pH of the composition, polishing speed, polishing selectivity, etc. The pH adjusting agent for adjusting the pH can use a pH adjusting agent capable of adjusting the pH without affecting the characteristics of the slurry composition for chemical mechanical polishing. In one embodiment of the present application, the pH adjusting agent can be an acidic or basic pH adjusting agent to achieve an appropriate pH.

[0383] In one embodiment of the present application, the pH adjuster can be, for example, one or more inorganic acids selected from sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, one or more organic acids selected from acetic acid, citric acid, glutaric acid, glycolic acid, formic acid, lactic acid, malic acid, dauric acid, maleic acid, oxalic acid, phthalic acid, succinic acid, tartaric acid, one or more amino acids selected from lysine, glycine, alanine, arginine, valine, leucine, isoleucine, methionine, cysteine, proline, histidine, phenylalanine, serine, tris(hydroxymethyl)methylamine, tyrosine, aspartic acid, tryptophan, and amino acids, imidazole, alkylamines, alcoholamines, quaternary ammonium bases, ammonia, or a combination thereof. In particular, the pH adjuster can be triethanolamine, tetramethylammonium hydroxide (TMAH or TMAOH), or tetraethylammonium hydroxide (TEAH or TEA-OH). In addition, the pH adjuster can be, for example, one or more selected from methylpropanolamine (AMP), tetramethylammonium hydroxide (TMAH), potassium hydroxide, sodium hydroxide, magnesium hydroxide, rubidium hydroxide, cesium hydroxide, sodium bicarbonate, sodium carbonate, triethanolamine, tromethamine, and nicotinamide. Preferably, the pH adjuster can be triethanolamine or tromethamine.

[0384] In one embodiment of the present application, the solvent can be any solvent used for a slurry composition for chemical mechanical polishing, for example, deionized water can be used, but the present application is not limited thereto. In addition, preferably, ultrapure water is used. The content of the solvent can be the remaining content with respect to the total content of the slurry composition for chemical mechanical polishing, excluding the content of the cerium oxide particles and other additional additives. In one embodiment of the present application, the solvent includes water (for example, deionized water) as an aqueous carrier and one or more water-miscible organic solvents. The organic solvents that can be used include, for example, alcohols such as propylene alcohol, isopropyl alcohol, ethanol, 1-propanol, methanol, 1-hexanol, and the like; aldehydes such as acetaldehyde and the like; ketones such as acetone, diacetone alcohol, methyl ethyl ketone, and the like; esters such as ethyl formate, propyl formate, ethyl acetate, methyl acetate, methyl lactate, butyl lactate, ethyl lactate, and the like; ethers including sulfoxides (for example, dimethyl sulfoxide (DMSO)), tetrahydrofuran, dioxane, diethylene glycol dimethyl ether, and the like; amides such as N,N-dimethylformamide, dimethylimidazolidinone, N-methylpyrrolidone, and the like; polyhydric alcohols and their derivatives such as ethylene glycol, glycerol, diethylene glycol, diethylene glycol monomethyl ether, and the like; and nitrogen-containing organic compounds such as acetonitrile, pentylamine, isopropylamine, dimethylamine, and the like.

[0385] In one embodiment of the present application, the polishing composition further comprises one or more other additives as the case requires. The polishing composition can include a surfactant and / or a rheology modifier, such as a high-molecular rheology modifier such as polyurethane, a biocide (e.g., KATHON LX), and the like. Suitable surfactants include, for example, cationic surfactants, anionic surfactants, anionic polyelectrolytes, nonionic surfactants, amphoteric surfactants, fluorosurfactants, and mixtures thereof, and the like. TM Suitable surfactants include, for example, cationic surfactants, anionic surfactants, anionic polyelectrolytes, nonionic surfactants, amphoteric surfactants, fluorosurfactants, and mixtures thereof, and the like.

[0386] In one embodiment of the present application, the slurry composition for chemical mechanical polishing has excellent dispersion stability, and in particular, has a high polishing rate for silicon oxide films.

[0387] The slurry composition for chemical mechanical polishing can be provided in the form of a one-liquid slurry composition containing all components such as ceria particles, a solvent, and other additives, or can be provided in the form of a two-liquid or three-liquid slurry composition in which the components are stored in two or more containers and mixed at the time of use or near the time of use, as the case requires. The selection of the provision method and the combination of the stored components are within the common general knowledge in the art, and the overall polishing characteristics and polishing rate can be adjusted by changing the mixing ratio.

[0388] In one embodiment of the present application, the slurry composition for chemical mechanical polishing can have a silicon oxide film polishing rate of Preferably, More preferably, Preferably, the higher the oxide film polishing rate, the better, and thus, there is no upper limit, but the silicon oxide film polishing rate is preferably More preferably, More preferably, More preferably, More preferably, More preferably, or More preferably. In particular, in the slurry composition for chemical mechanical polishing using ceria particles according to one embodiment of the present application, even if the ceria particles are in the low content range, the number of particles contained is greater than that of a slurry composition containing conventional ceria particles due to the small particle size, and the content of Ce 3+ on the surface is high, so that the Si-O-Ce bond is increased, and thus, the silicon oxide film polishing rate can be significantly improved.

[0389] In one embodiment of the present application, the polishing selectivity ratio of the oxide film / polysilicon film of the slurry composition for chemical mechanical polishing can be 50 or more, 100 or more, 150 or more, or 200 or more, and the polishing selectivity ratio of the oxide film / polysilicon film can be 3,000 or less, 2,000 or less, 1,500 or less, 1,000 or less, 900 or less, or 800 or less. The oxide film / polysilicon film selectivity ratio is not excluded from achieving a selectivity ratio of 3,000 or more by appropriately adjusting the content of the cationic polymer.

[0390] When the cerium oxide is used as a polishing material, since the cerium oxide has strong reactivity with the silicon oxide, Si-O-Ce chemical bonding occurs, and thus, unlike mechanical polishing that removes only a hydration layer formed on the surface, the cerium oxide is removed in a manner of peeling off a silicon oxide block from the surface of the silicon oxide film to polish the silicon oxide film. In addition, the cerium oxide powder of the embodiment of the present application has a small particle size, and thus, has low strength, and has excellent global flatness at the time of polishing, and also, can solve the problem of forming micro scratches due to large particles.

[0391] Another embodiment of the present application provides a slurry composition for chemical mechanical polishing, including cerium oxide particles, a solvent, and a cationic polymer.

[0392] In one embodiment of the present application, the polishing rate of the oxide film can increase with the content of the cationic polymer. This is a main technical feature of the slurry composition for chemical mechanical polishing of the present application that is distinguished from the prior art, and thus, will be described in detail below.

[0393] In one embodiment of the present application, the cationic polymer can play two roles in the slurry composition for chemical mechanical polishing of the present application. First, the cationic polymer can play the role of a stabilizer for the slurry composition to ensure particle dispersibility and dispersion stability in the manner of a pH buffer. In addition, the cationic polymer of the present application can play the role of a polishing accelerator for the oxide film. In the existing polishing slurry, the cationic polymer is added to improve dispersion stability, or to protect a field oxide layer when removing a height difference, and in order to obtain such characteristics, a part of the polishing rate of the oxide film has to be sacrificed. In contrast, the cationic polymer added to the polishing slurry of the present application can not only improve dispersion stability, but also increase the total polishing rate for the oxide film as the amount of the cationic polymer added increases.

[0394] In one embodiment of the present application, the content of the cationic polymer can be 0.001% by weight or more, 0.002% by weight or more, 0.003% by weight or more, 0.004% by weight or more, or 0.005% by weight or more, and can be 1% by weight or less, 0.5% by weight or less, 0.1% by weight or less, 0.05% by weight or less, 0.03% by weight or less, or 0.01% by weight or less, based on the total weight of the slurry composition for chemical mechanical polishing. When the content of the cationic polymer based on the total weight of the slurry composition for chemical mechanical polishing is less than 0.001%, the content is too low to sufficiently function as a polishing accelerator, and thus the polishing rate cannot be affected. On the contrary, when it is more than 1%, the added cationic polymer can interfere with the polishing process of cerium oxide, and thus the polishing rate can be decreased.

[0395] In one embodiment of the present invention, the cationic polymer may be a polymer or copolymer containing amine or ammonium groups. For example, in one embodiment of the present invention, the cationic polymer may be polydiallyldimethyl ammonium chloride, polyallylamine, polyethyleneimine, polydiallylamine, polypropyleneimine, polyacrylamide-co-diallyldimethyl ammonium chloride, polyacrylamide, or a combination thereof, preferably polydiallyldimethyl ammonium chloride, polyallylamine, polyethyleneimine, polyacrylamide-co-diallyldimethyl ammonium chloride, polyacrylamide, poly(trimethylaminoethyl methacrylate) (ethylmethacrylate), dicyandiamide-diethylenetriamine copolymer, diallyldimethylamine / hydrochloride-acrylamide copolymer, dicyandiamide-formaldehyde copolymer, or combinations thereof.

[0396] A third embodiment of the present invention provides a method for manufacturing a semiconductor device, comprising the following steps: grinding using the chemical mechanical polishing slurry composition.

[0397] Detailed descriptions of portions that overlap with the first and second embodiments of the present invention have been omitted; however, even if such descriptions are omitted, the descriptions of the first and second embodiments of the present invention are equally applicable to the third embodiment.

[0398] The method for manufacturing a semiconductor device according to the third embodiment of the present invention will be described in detail below.

[0399] First, according to the shallow trench isolation (STI) routine process, photolithography, etching, and cleaning (polishing) can be classified as common basic processes in the process of planarizing insulating films.

[0400] To separate the devices, the process begins with photolithography as the first step. Photolithography is performed on an auxiliary device called a track and an exposure machine that performs exposure to copy the circuit pattern (mask) onto the wafer. First, a photosensitive agent is applied. Due to the high viscosity of the photosensitive agent, it needs to be thinly applied to the insulating film while the wafer is rotating. Only when the photosensitive agent is applied uniformly will the depth of exposure be appropriate. If the depth of exposure is insufficient, photosensitive agent residue will be left during development, and the underlying film (insulating layer) cannot be properly removed in the subsequent etching process. After exposure, the wafer is moved back to the track for the development process to remove the photosensitive areas.

[0401] As the second step, STI etching is a process that removes part of the insulating layer (oxide layer + nitride layer) and substrate directly below the developing area (the area where the photosensitive film is removed). This etching process can utilize either a dry or wet process. Dry etching typically employs a plasma state for etching. Compared to wet (liquid) etching, dry etching does not etch the sidewalls (anisotropic etching), only the bottom, thus facilitating the shaping of the groove. However, over-etching may occur, so it must be performed only after accurately calculating the etching endpoint. Residue is left after etching, and therefore requires treatment.

[0402] After the groove shape is etched, the photosensitive layer is no longer needed and can therefore be removed by ashing. Preferably, plasma is used for the ashing process, which allows for more precise ashing. The shape of the semiconductor device after the ashing process is shown in [Figure / Image]. Figure 2 middle.

[0403] A method for manufacturing a semiconductor device according to one embodiment of the present invention may include the following steps: simultaneously polishing a silicon oxide film, a silicon nitride film, and a polycrystalline silicon film using the chemical mechanical polishing slurry composition.

[0404] Figures 2 to 6 This is a cross-sectional view illustrating a semiconductor device manufacturing method according to an embodiment of the present invention.

[0405] ReferenceFigure 2 A groove 13 can be formed in the upper film 11 on the lower film 10. As an example, the upper film 11 can be formed on the lower film 10, and a nitride film (polish stop film) 12 can be formed on the upper film 11. The lower film 10 can include any material film. For example, the lower film 10 can be an insulating film, a conductive film, a semiconductor film, or a semiconductor wafer (substrate). The upper film 11 can include an insulating film (oxide film), a conductive film, a semiconductor film, or a combination thereof.

[0406] When the upper film 11 includes a plurality of laminated insulating films, the insulating films can be the same kind or different from each other. As an example, the upper film 11 can include a plurality of silicon oxide films and a plurality of silicon nitride films alternately and repeatedly laminated. The upper film 11 can further include a semiconductor film and a lower insulating film under the plurality of silicon oxide films and the plurality of silicon nitride films. For example, the lower insulating film can be disposed under the semiconductor film.

[0407] For example, silicon nitride (e.g., SiN), polysilicon, metal nitride (e.g., TiN), metal, or the like can be deposited to make the nitride film (polish stop film) 12 have a large thickness (e.g., 1,000 A or more). The groove 13 can be formed by an etching process or a drilling process. The groove 13 can have a depth that can reach the lower film 10 through the nitride film (polish stop film) 12 and the upper film 11. For example, the groove 13 can have a depth sufficient to expose the lower film 10.

[0408] Referring to Figure 3 In the STI, an oxide film can be formed as a double structure. First, a thin liner oxide film is formed as a first insulating film 14 in a diffusion manner before an insulating material is actually filled in the groove 13 for securing a space. This is to smoothly form a second insulating film on a silicon substrate by CVD deposition in a subsequent step. According to another implementation example of the present invention, when the groove 13 is filled by high-density plasma CVD (HDPCVD), it is also possible to function to avoid damage caused by plasma having high energy. According to an implementation example of the present invention, the first insulating film (liner oxide film) can be formed as a thin film such as a gate oxide film by supplying oxygen to a diffusion furnace (furnace) and heating at a high temperature. In addition, according to another implementation example of the present invention, a nitride film can be used instead of the oxide film.

[0409] Referring to Figure 4A plurality of insulating materials can be deposited to form the first insulating film 14 and the second insulating film 15 for filling the groove 13. The density and deposition rate of the first insulating film 14 and the second insulating film 15 can be different from each other. According to an embodiment of the present application, the first insulating film 14 can be deposited from a high-density insulating material, and the second insulating film 15 can be deposited from a low-density insulating material. As an example, the first insulating film 14 can be deposited and patterned from a high-density plasma (HDP) oxide. The first insulating film 14 can be formed in a shape extending along the inner surface of the groove 13. For example, the first insulating film 14 can have a U-shape or a tubular shape with an upward opening.

[0410] Since the first insulating film 14 has a high density, it is difficult to generate voids in the first insulating film 14, and thus, when a subsequent heat treatment process is performed, cracks due to the voids can be prevented or significantly reduced. For example, the second insulating film 15 can be formed by filling the groove 13 in which the first insulating film 14 is formed with a tetraethyl orthosilicate (TEOS) oxide and depositing it to a thickness sufficient to cover the polishing stop film 12. The second insulating film 15 can be formed at a faster deposition rate than the first insulating film 14. Since the second insulating film 15 is deposited at a fast rate, the groove 13 can be filled with the second insulating film 15 faster.

[0411] According to another embodiment of the present application, although not shown, the second insulating film 15 can be partially removed so that the second insulating film 15 remains on the groove 13. For example, the second insulating film 15 can be selectively removed using a photolithography process and an etching process to define or open a specific area such as a unit memory area of a semiconductor device. Thus, a part or all of the second insulating film 15 on the polishing stop film 12 can be removed, and the second insulating film 15 can also remain on the groove 13. The opening process of the specific area can be selectively performed and is not necessarily required.

[0412] Referring to Figure 5 A planarization process can be performed on the second insulating film 15. For example, the second insulating film 15 can be planarized by a chemical mechanical polishing (CMP) process. The chemical mechanical polishing process can be continuously performed until the nitride film (polishing stop film) 12 is exposed. The chemical mechanical polishing process can be performed after the second insulating film 15 is formed in Figure 4 At this time, the surface of the nitride film (polishing stop film) 12 is relatively flat, or even if it is not flat, the non-flatness is not severe, and thus, the chemical mechanical polishing process can be easily performed.

[0413] Next, referring to Figure 6The nitride film can be removed to form the STI. The purpose of the nitride film is to protect the upper film 11 from the first insulating film 14. The upper film 11 can become a gate oxide film that requires thinness and high reliability, and thus, careful handling is required. When the nitride film is removed by etching (wet), the wafer can be immersed in a chemical solution so that only the nitride film is etched, and the oxide film is not etched. For this purpose, a solution having a high selectivity (etching ratio) for the nitride film can be used. In another embodiment of the present application, the nitride film can also be removed by CMP. At this time, etching is not required for the nitride film, but physical damage can be caused to the oxide film, and thus, chemical treatment of the nitride film by etching is preferably performed to protect the oxide film.

[0414] According to another embodiment of the present application, the chemical mechanical polishing (CMP) process removes the first insulating film 14 and the second insulating film 15 on the upper portion of the nitride film (polishing stop film) 12 after the gap filling to isolate the active region from the field region, as shown in FIG. 1C. Figure 7 The process can be roughly divided into three steps, as shown in FIG. 1D.

[0415] The first step is bulk CMP of the second insulating film 15 on the platen to achieve local planarization. The second step is polishing or cleaning of the second insulating film 15 with the height difference relaxed on the platen, and stopping the polishing at the time when the nitride film (polishing stop film) 12 is exposed. At this time, end point detection (EPD) can be used to sense the time when the different film quality is exposed. The third step is to remove the second insulating film 15 residue that can remain on the nitride film (polishing stop film) 12 on the platen, and to polish the nitride film and the oxide film to target.

[0416] Figure 8 The structure of a chemical mechanical polishing (CMP) apparatus of an embodiment of the present application is shown. The apparatus can have three platens, and as previously described, can be a structure in which the STI CMP process is sequentially performed on the platens 1, 2, and 3 to perform each step. After the polishing is completed, the process is terminated after moving to a cleaning section and cleaning is completed.

[0417] In addition, in the method of manufacturing a semiconductor device according to an embodiment of the present application, the method of simultaneously polishing a silicon oxide film, a silicon nitride film, and a polysilicon film using the slurry composition for chemical mechanical polishing can employ a polishing method and conditions commonly used in the related art, and is not particularly limited in the present application.

[0418] The slurry composition for chemical mechanical polishing according to an embodiment of the present application has high dispersion stability, and the Ce 3+ The content of CeO2 is high, and the polishing rate for a silicon-containing substrate can be increased based on a chemical polishing mechanism of Si-O-Ce between silicon dioxide and cerium, and thus, even in a condition where the content of the included CeO2 is low, it can be particularly effectively used for removing a silicon oxide film from the surface of a semiconductor device in a CMP process.

[0419] A fourth embodiment of the present application provides a semiconductor device including: a substrate; and a groove on the substrate and filled with an insulating material, wherein the groove is generated by polishing at least one film selected from a silicon oxide film, a silicon nitride film, and a polysilicon film using a slurry composition for chemical mechanical polishing, wherein the slurry composition for chemical mechanical polishing includes ceria particles and a solvent, and wherein, in a 1.0 wt% aqueous dispersion liquid in which the content of the ceria particles is adjusted, the light transmittance for light having a wavelength of 500 nm is 50% or more.

[0420] Detailed descriptions of portions that are repeated with the first to third embodiments of the present application are omitted, but even if the descriptions are omitted, the descriptions regarding the first to third embodiments of the present application are equally applicable to the fourth embodiment.

[0421] A fifth embodiment of the present application provides a method for manufacturing ceria particles for chemical mechanical polishing, including the steps of: preparing a raw material precursor; and pulverizing or precipitating ceria particles in a solution including the raw material precursor to obtain a dispersion liquid of ceria particles for chemical mechanical polishing, wherein, in a 1.0 wt% aqueous dispersion liquid in which the content of the ceria particles is adjusted, the light transmittance for light having a wavelength of 500 nm is 50% or more.

[0422] Detailed descriptions of portions that are repeated with the first to fourth embodiments of the present application are omitted, but even if the descriptions are omitted, the descriptions regarding the first to fourth embodiments of the present application are equally applicable to the fifth embodiment.

[0423] In an embodiment of the present application, a step of preparing a raw material precursor can be included. The raw material precursor is only a precursor substance that can manufacture ceria particles as a product.

[0424] In one embodiment of the present invention, the following steps may be included: pulverizing or precipitating cerium oxide particles in a solution containing the raw material precursor to obtain a dispersion of cerium oxide particles for chemical mechanical polishing. The step of pulverizing the cerium oxide particles in the solution containing the raw material precursor can, for example, be performed by a grinding process, and the pulverization method can be determined without limitation within the scope of the technical knowledge of those skilled in the art. The step of precipitating the cerium oxide particles in the solution containing the raw material precursor to obtain a dispersion of cerium oxide particles for chemical mechanical polishing may further include a step of removing the supernatant; or a filtration step, etc.

[0425] In one embodiment of the present invention, the cerium precursor may be at least one selected from cerium ammonium nitrate, cerium nitrate, cerium ammonium sulfate, cerium acetate, cerium chloride, cerium hydroxide, and cerium oxide.

[0426] In one embodiment of the present invention, the filtration step can be performed without limitation using a filtration device, and more preferably using a membrane filter. The cerium oxide particles produced by the method according to an embodiment of the present invention not only have a high yield in their synthesis, but also, through a further filtration step, almost completely remove cerium precursor substances.

[0427] The above description of the present invention is illustrative, and those skilled in the art should understand that it can be readily implemented in other forms without altering the technical concept or essential features of the invention. Therefore, it should be understood that the above embodiments are exemplary and not limiting in all respects. For example, individual components described as a single type can also be implemented in a distributed form; similarly, multiple components described as distributed can also be implemented in a combined form.

[0428] The scope of this invention is defined by the appended claims, and all modifications or variations derived from the meaning and scope of the claims and their equivalents are included within the scope of this invention.

[0429] Industrial applicability

[0430] In one embodiment of the present invention, cerium oxide particles increase the Ce content on the cerium oxide surface. 3+ Despite its small particle size, it exhibits a high oxide film removal rate even at low concentrations when included in chemimechanical grinding slurries.

[0431] In addition, according to an embodiment of the present invention, cerium oxide particles for a chemical mechanical polishing slurry composition and a chemical mechanical polishing slurry composition comprising the present invention can be provided, which can minimize surface defects of wafers and, unlike the prior art which is considered a trade-off relationship between surface defects and oxide film removal rate, can minimize surface defects while maximizing oxide film removal rate.

[0432] In addition, according to an embodiment of the present application, it is possible to further improve the polishing rate of the oxide film while improving the oxide film / polysilicon film selectivity by adding a cationic polymer. It can be considered as a unique effect of the present application that the addition of the cationic polymer is generally considered to sacrifice the polishing rate to secure other characteristics in view of the technical common sense in the prior art.

[0433] The effects of the present application are not limited to the above-described effects, and it should be understood that all effects capable of being inferred from the features of the application described in the detailed description of the present application or the claims of the present application are included.

Claims

1. Cerium oxide particles for chemical mechanical polishing, characterized in that, an electron energy loss spectrum of the cerium oxide particles includes a first peak of 876.5 to 886.5 eV and a second peak of 894.5 to 904.5 eV, a maximum intensity of the first peak is larger than a maximum intensity of the second peak, further comprising a third peak in the range of 886.5 to 889.5 eV and a fourth peak in the range of 904.5 to 908.5 eV, the sum of the areas of the third peak interval P1 and the sum of the areas of the fourth peak interval P2 relative to the total sum of the areas of the peaks of the electron energy loss spectrum P t are 0.1 or less, the ratio (P1+P2) / P t is 0.1 or less. a light transmittance for light having a wavelength of 500 nm is 50% or more in an aqueous dispersion in which a content of the cerium oxide particles is adjusted to 1.0% by mass, a particle diameter of the cerium oxide particles measured by a dynamic light scattering (DLS) particle size analyzer is set to a, and a particle diameter of the cerium oxide particles measured by a transmission electron microscope (TEM) is set to b, and at this time, the cerium oxide particles satisfy the following formula 2, [Formula 2] a ≤ 2.2b.

2. The cerium oxide particles for chemical mechanical polishing according to claim 1, characterized in that, an average light transmittance for light having a wavelength of 450 to 800 nm is 50% or more in an aqueous dispersion in which a content of the cerium oxide particles is adjusted to 1.0% by mass.

3. The cerium oxide particles for chemical mechanical polishing according to claim 1, characterized in that, a secondary particle diameter of the cerium oxide particles measured by a dynamic light scattering particle size analyzer is 1 to 30 nm.

4. The cerium oxide particles for chemical mechanical polishing according to claim 1, characterized in that, a secondary particle diameter of the cerium oxide particles measured by a dynamic light scattering particle size analyzer is 1 to 20 nm.

5. The cerium oxide particles for chemical mechanical polishing according to claim 1, characterized in that, a primary particle diameter of the cerium oxide particles is 0.5 to 15 nm when X-ray diffraction analysis is performed.

6. Cerium oxide particles for chemical mechanical polishing, characterized in that, wherein a light transmittance for light having a wavelength of 500 nm is 50% or more in an aqueous dispersion in which a content of the cerium oxide particles is adjusted to 1.0% by mass, When X-ray photoelectron spectroscopy analysis is performed on the surface of the cerium oxide particles, the X-ray photoelectron spectroscopy peak representing the Ce-O binding energy includes a first peak of 900.2 to 902.2 eV, a second peak of 896.4 to 898.4 eV, a third peak of 885.3 to 887.3 eV, and a fourth peak of 880.1 to 882.1 eV, 3+ the X-ray photoelectron spectroscopy peak representing the Ce-O binding energy includes a first peak of 900.2 to 902.2 eV, a second peak of 896.4 to 898.4 eV, a third peak of 885.3 to 887.3 eV, and a fourth peak of 880.1 to 882.1 eV, When X-ray photoelectron spectroscopy is performed, the ratio of the sum of the X-ray photoelectron spectroscopy peak areas representing the Ce-O binding energy of Ce 3+ of the cerium oxide particles to the total sum of the X-ray photoelectron spectroscopy peak areas representing the Ce-O binding energy of the surface of the cerium oxide particles is 0.29 to 0.70, a particle diameter of the cerium oxide particles measured by a dynamic light scattering (DLS) particle size analyzer is set to a, and a particle diameter of the cerium oxide particles measured by a transmission electron microscope (TEM) is set to b, and at this time, the cerium oxide particles satisfy the following formula 2, [Formula 2] a ≤ 2.2b.

7. A slurry composition for chemical mechanical polishing, characterized in that, it includes the cerium oxide particles according to claim 1 or 6 and a solvent.

8. The slurry composition for chemical mechanical polishing according to claim 7, characterized in that, a content of the cerium oxide particles is 0.01 to 5 parts by mass based on 100 parts by mass of the total weight of the slurry composition for chemical mechanical polishing.

9. The slurry composition for chemical mechanical polishing according to claim 7, characterized in that, a pH of the slurry composition for chemical mechanical polishing is 2 to 10.

10. The slurry composition for chemical mechanical polishing according to claim 7, characterized in that, ​ ​ The slurry composition for chemical mechanical polishing contains an inorganic acid, an organic acid, an amino acid, an imidazole, an alkylamine, an alcohol amine, a quaternary ammonium base, ammonia, or a combination thereof, wherein the inorganic acid is one or more selected from sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid, the organic acid is one or more selected from acetic acid, citric acid, glutaric acid, glycolic acid, formic acid, lactic acid, malic acid, dauric acid, maleic acid, oxalic acid, phthalic acid, succinic acid, and tartaric acid, and the amino acid is one or more selected from lysine, glycine, alanine, arginine, valine, leucine, isoleucine, methionine, cysteine, proline, histidine, phenylalanine, serine, tris(hydroxymethyl)methylglycine, tyrosine, aspartic acid, tryptophan, and aminotryptophan.

11. The slurry composition for chemical mechanical polishing according to claim 7, wherein the solvent is deionized water.

12. The slurry composition for chemical mechanical polishing according to claim 7, wherein the solvent is deionized water.

13. A method for manufacturing a semiconductor device, comprising the step of polishing using the slurry composition for chemical mechanical polishing according to claim 7. The slurry composition for chemical mechanical polishing has a polishing rate of a silicon oxide film of 1000 A / min or less.

14. A method for manufacturing a semiconductor device, comprising the steps of: preparing a raw material precursor; 14. A method for producing cerium oxide particles for chemical mechanical polishing according to claim 1 or 6, characterized by, and obtaining a dispersion liquid of ceria particles for chemical mechanical polishing by pulverizing or precipitating ceria particles in a solution containing the raw material precursor, wherein the transmittance of light having a wavelength of 500 nm in a water dispersion liquid in which the content of the ceria particles is adjusted to 1.0% by weight is 50% or more. ​ ​

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