Colloidal silica and chemical mechanical polishing composition comprising same

Abstract

The present invention relates to colloidal silica useful as abrasive particles. Specifically, the colloidal silica has a first peak at 533 ± 0.5 eV and a second peak at 534 ± 0.5 eV in a spectrum obtained by X-ray photoelectron spectroscopy (XPS), the first peak having an intensity greater than that of the second peak, and, with respect to storage modulus (G', Pa) and loss modulus (G", Pa) as a function of shear strain (%) obtained under conditions of a temperature of 20°C, a 20 wt% aqueous dispersion of colloidal silica, a frequency of 1 Hz, and a shear strain sweep of 0.10% to 100.00%, a crossover between the storage modulus (G') and the loss modulus (G") occurs at a shear strain of 2.00% to 5.00%, and a maximum storage modulus (G') in the shear strain range of 0.10% to 0.20% is 0.80 Pa or less.

Description

Colloidal silica and a chemical mechanical polishing composition containing the same

[0001] The present invention relates to colloidal silica and a chemical mechanical polishing composition containing the same.

[0002] Colloidal silica is a material in which silica particles with a particle size ranging from about 1 to 200 nm are stably dispersed in a liquid medium. Colloidal silica is used in various applications, such as metal surface treatment, coatings, abrasives, catalyst carriers, and medical materials. Various types of colloidal silica suitable for specific purposes can be manufactured by controlling the size, surface characteristics, crystallinity, and dispersion stability of the silica particles.

[0003] Traditionally, the method of obtaining silica sol by neutralizing sodium silicate with acid has been widely used for the production of colloidal silica. However, this method has the disadvantage that it is difficult to ensure product quality uniformity during the manufacturing process. Recently, various methods are being studied to overcome this disadvantage. For example, methods for producing colloidal silica by hydrolyzing organosilane precursors and methods for directly synthesizing silica nanoparticles have been reported.

[0004] However, to enhance industrial applicability, not only must more economical manufacturing processes be developed, but there is also a need to develop colloidal silica with uniform physicochemical properties.

[0005] One aspect of the present invention is to provide colloidal silica having excellent scratch resistance and an improved polishing speed when polishing a silicon wafer substrate.

[0006] Another aspect of the present invention is to provide colloidal silica having uniform physicochemical properties through a continuous synthesis process.

[0007] The problems of the present invention are not limited to those described above. A person skilled in the art to which the present invention pertains will have no difficulty understanding additional problems of the present invention from the overall contents of this specification.

[0008] Colloidal silica according to one aspect of the present invention has a first peak of 533±0.5 eV and a second peak of 534±0.5 eV in an XPS spectrum measured by X-ray photoelectron spectroscopy (XPS), wherein the intensity of the first peak is greater than the intensity of the second peak, and in the storage factor (G', Pa) and loss factor (G'', Pa) according to shear strain (%) obtained under the following conditions, a crossover occurs between the storage factor (G') and the loss factor (G˝) at a shear strain of 2.00% to 5.00%, and the maximum storage factor (G') in the region of a shear strain of 0.10% to 0.20% is 0.80 Pa or less.

[0009] Conditions: Temperature 20℃, 20 wt% colloidal silica aqueous dispersion, 1 Hz frequency, 0.10%–100.00% shear strain sweep

[0010] In one embodiment, the loss coefficient (G˝) at the point where a crossover occurs between the storage coefficient and the loss coefficient. c ) may be 0.10 Pa or less.

[0011] In one embodiment, G˝, which is the maximum loss factor value in the shear strain region of 0.10% to 1.00%. LSS and G˝, the maximum loss factor value in the shear strain region of 40.00% to 100.00% HSS The absolute value of the difference between them can be 0.10 Pa or less.

[0012] In one embodiment, the colloidal silica may have a viscosity of 1.0 to 7.0 mPa·s measured under the following conditions.

[0013] Conditions: Temperature of 20℃, 20 wt% colloidal silica aqueous dispersion, 100 s -1 shear rate

[0014] In one embodiment, the ratio (I1 / I2) of the intensity of the first peak (I1) and the intensity of the second peak (I2) of the XPS spectrum may be 1.10 to 5.00.

[0015] In one embodiment, in the spectrum measured by the Raman spectroscopy, 550±70 cm⁻¹ -1 It may not include a D2 scattering peak in the wavenumber region.

[0016] In one embodiment, the BET specific surface area of ​​the colloidal silica is 30.0 to 150.0 m² 2 It can be / g.

[0017] In one embodiment, the average particle size (D) of the colloidal silica in the aqueous dispersion 50 ) can be 30.0 to 250.0 nm.

[0018] In one embodiment, D of the colloidal silica 50 / (D 90 -D 10 ) can be 1.10 to 4.00.

[0019] In one embodiment, the colloidal silica is a colloidal factor (C of Formula 1 below) f ) can satisfy 0.60 to 2.50.

[0020] [Equation 1]

[0021]

[0022] In the above Equation 1, I1 represents the intensity of the first peak with a binding energy of 533±0.5 eV in the XPS spectrum, and I2 represents the intensity of the second peak with a binding energy of 534±0.5 eV.

[0023] In one embodiment, the colloidal silica may be produced in a continuous flow reactor.

[0024] A chemical mechanical polishing composition according to one aspect of the present invention comprises the aforementioned colloidal silica as abrasive particles.

[0025] In one embodiment, the chemical mechanical polishing composition may further include one or more selected from the group consisting of water-soluble polymers, glycol-based compounds, pH adjusters, chelating agents, surfactants, and basic compounds.

[0026] Colloidal silica according to one aspect of the present invention can provide excellent scratch resistance and improved polishing speed when polishing a silicon wafer substrate.

[0027] Colloidal silica according to another aspect of the present invention can be manufactured through a continuous synthesis process and can have uniform physicochemical properties as the synthesis process is maintained at a constant level.

[0028] A method for manufacturing colloidal silica according to another aspect of the present invention substantially does not involve toxic organic solvents in the synthesis process, minimizes the emission of volatile organic compounds (VOCs) during the synthesis process, and ensures the safety of the working environment, thereby enabling the continuous production of colloidal silica.

[0029] The various and beneficial advantages and effects of the present invention are not limited to those described above and will be more easily understood in the process of explaining specific embodiments of the present invention.

[0030] FIG. 1 is a perspective view and an enlarged cross-sectional view of an injection port area illustrating a continuous tubular reactor used in the production of colloidal silica according to one embodiment.

[0031] FIG. 2 is a transmission electron microscope image of colloidal silica particles prepared according to one embodiment, and

[0032] Figure 3 is a transmission electron microscope image of colloidal silica particles prepared according to another embodiment.

[0033] Unless otherwise defined, technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art to which this invention pertains, and descriptions of known functions and configurations that could unnecessarily obscure the essence of the invention are omitted in the following description and accompanying drawings.

[0034] Additionally, the singular form used in this specification may be intended to include the plural form unless specifically indicated otherwise in the context.

[0035] Additionally, units used herein without special reference are based on weight, and, for example, units of % or ratio mean weight % or weight ratio, and weight % means the weight percentage of any one component of the total composition that occupies the composition, unless otherwise defined.

[0036] Additionally, the numerical ranges used in this specification include lower and upper limits and all values ​​within the range, increments logically derived from the form and width of the defined range, all of which are limited values, and all possible combinations of upper and lower limits of numerical ranges defined in different forms. Unless otherwise specifically defined in this specification, values ​​outside the numerical range that may occur due to experimental error or rounding are also included in the defined numerical range.

[0037] The term "comprising" in this specification is an open description having an equivalent meaning to expressions such as "comprising," "containing," "having," or "characterizing," and does not exclude elements, materials, or processes not additionally listed.

[0038] The present invention will be described in detail below through each embodiment or example of the invention. It should be noted that each embodiment or example described in this specification is not limited to a single embodiment or example, but may also be combined with other embodiments or examples. Accordingly, the citation of claims in the patent claims is merely an example of an embodiment, and the technical concept of the present invention should not be interpreted as being limited only to a combination with the cited claims; rather, combinations with various claims are also included within the scope of the technical concept of the present invention.

[0039] Unless otherwise defined in this specification, the average particle size is D 50 It can be defined as, and the average particle size is the volume-based median diameter (D 50 It means ). Cumulative volume standard D 50 represents the particle diameter at the point where the cumulative volume % is 50 volume % in the cumulative particle size distribution curve accumulated in order of particle diameter. Experimentally, D 50 The cumulative distribution curve including can be measured by a particle size analyzer based on dynamic light scattering. Similarly, cumulative volume reference D 10 and D 90 represents the particle size at points where the cumulative volume % is 10 volume % and 90 volume %.

[0040] Colloidal silica according to one aspect of the present invention has a first peak of 533±0.5 eV and a second peak of 534±0.5 eV in an XPS spectrum measured by X-ray photoelectron spectroscopy (XPS), wherein the intensity of the first peak is greater than the intensity of the second peak, and in the storage factor (G', Pa) and loss factor (G˝, Pa) according to shear strain (%) obtained under the following conditions, a crossover between the storage factor (G') and the loss factor (G˝) occurs at a shear strain of 2.00% to 5.00%, and the maximum storage factor (G') in the region of a shear strain of 0.10% to 0.20% is 0.80 Pa or less.

[0041] Conditions: Temperature 20℃, 20 wt% colloidal silica aqueous dispersion, 1 Hz frequency, 0.10%–100.00% shear strain sweep

[0042] In detail, the XPS spectrum of colloidal silica may be an XPS O1s spectrum. Colloidal silica may have a first peak in the XPS O1s spectrum where the center of the peak is located at 532.5 to 533.5 eV, specifically 532.7 to 533.3 eV, and more specifically 532.8 to 533.2 eV. In addition, colloidal silica may have a second peak in the XPS O1s spectrum where the center of the peak is located at 533.5 to 534.5 eV, specifically 533.7 to 534.3 eV, and more specifically 533.8 to 534.2 eV. In this case, the center of one peak in the XPS spectrum refers to the binding energy at the maximum point (maximum intensity) of the corresponding peak, and the intensity of one peak in the XPS spectrum refers to the area intensity of the corresponding peak.

[0043] As described above, colloidal silica has a first peak and a second peak in the XPS spectrum, and the intensity of the first peak is greater than the intensity of the second peak. At the same time, in the diagram of the storage factor and loss factor according to shear strain (hereinafter, G'-G˝ diagram), a crossover between the storage factor and the loss factor occurs in the region of shear strain of 2.00% to 5.00%, and the maximum value of the storage factor (G') in the region of low shear strain of 0.10% to 0.20% is 0.80 Pa or less. The first peak and the second peak in the XPS spectrum of colloidal silica represent the chemical integrity in the surface region of the colloidal silica that comes into direct contact with the polishing target. Since the intensity of the first peak is greater than the intensity of the second peak, the colloidal silica can have improved mechanical properties and can exhibit a high polishing rate. In addition, the shear strain at the point where the crossover between the storage factor and the loss factor occurs in the G'-G˝ diagram of colloidal silica is closely related to the dispersibility, cohesiveness, and fluidity of the colloidal silica. The crossover at low shear strain in the 2.00% to 5.00% range and the very low maximum storage factor of 0.80 Pa or less in the 0.10% to 0.20% range, which corresponds to the linear viscoelasticity (LVE) region, indicate that the cohesiveness due to inter-particle interactions of the colloidal silica is very low, so each particle is dispersed substantially independently, and it has low shear resistance, high fluidity, and excellent dispersion stability.

[0044] As described above, colloidal silica can exhibit a high polishing rate and excellent scratch resistance by having a first peak intensity greater than the second peak intensity in the XPS spectrum, a crossover between the storage factor and the loss factor in the shear strain region of 2.00% to 5.00%, and a very low storage factor value of 0.80 Pa or less in the LVE region. When the first peak intensity in the XPS spectrum is smaller than the second peak intensity, the shear strain at which the crossover occurs increases, or a high storage factor value in the LVE region, the colloidal stability is significantly reduced, the scratch rate increases, and the polishing rate is significantly lower, which is undesirable.

[0045] Specifically, the shear strain (γ at the point where the crossover between the storage factor and the loss factor occurs in the G'-G˝ diagram of colloidal silica. c ) may be 2.00% to 5.00%, specifically 2.50% to 4.50%, more specifically 3.00% to 4.50%.

[0046] Specifically, in the G'-G˝ diagram of colloidal silica, the maximum storage modulus value in the low shear strain region of 0.10% to 0.20% may be 0.80 Pa or less, specifically 0.10 Pa to 0.80 Pa, more specifically 0.10 Pa to 0.70 Pa, and even more specifically 0.15 Pa to 0.70 Pa. As a substantial example, the average particle size (D) of the colloidal silica 50 When ) is 30 to 100 nm, the maximum storage modulus value in the low shear strain region of 0.10% to 0.20% in the G'-G˝ diagram of colloidal silica may be 0.10 Pa to 0.40 Pa, specifically 0.10 Pa to 0.30 Pa, more specifically 0.15 Pa to 0.25 Pa. As another substantial example, the average particle size (D) of the colloidal silica 50When ) is 100 to 250 nm, the maximum storage modulus value in the low shear strain region of 0.10% to 0.20% in the G'-G˝ diagram of colloidal silica may be 0.40 Pa to 0.80 Pa, specifically 0.50 Pa to 0.75 Pa, more specifically 0.55 Pa to 0.70 Pa.

[0047] In one embodiment, in the G'-G˝ diagram of colloidal silica, the loss factor (G˝) at the point where a crossover occurs between the storage factor and the loss factor. c ) can be 0.10 Pa or less, specifically 0.03 Pa to 0.10 Pa, more specifically 0.04 Pa to 0.09 Pa. Along with a low shear strain at the crossover point, a very small loss modulus value of 0.10 Pa or less (equivalent to the elastic modulus value depending on the crossover point) can indicate excellent dispersibility and fluidity of colloidal silica.

[0048] In one embodiment, G˝, which is the maximum loss factor value in the shear strain region of 0.10% to 1.00%. LSS and G˝, the maximum loss factor value in the shear strain region of 40.00% to 100.00% HSS The absolute value of the difference between them (|G˝ HSS - G˝ LSS |) may be 0.10 Pa or less, specifically 0 to 0.10 Pa. This means that the colloidal silica has a substantially constant loss factor in a wide shear strain region of 0.10% to 100.00% in the G'-G˝ diagram. Exhibiting a substantially constant loss factor in a wide shear strain region ranging from very low shear strain to very high shear strain means that the colloidal silica behaves substantially like a liquid even in a high concentration water dispersion state.

[0049] As a practical example, the average particle size (D) of colloidal silica 50When ) is 30 to 100 nm, in the G'-G˝ diagram of colloidal silica, |G˝ HSS - G˝ LSS | may be 0 to 0.05 Pa, specifically 0 to 0.04 Pa, more specifically 0 to 0.03 Pa, and even more specifically 0 to 0.02 Pa. As another substantial example, the average particle size (D of colloidal silica) 50 When ) is 100 to 250 nm, in the G'-G˝ diagram of colloidal silica, |G˝ HSS - G˝ LSS | may be 0.03 Pa to 0.10 Pa, specifically 0.04 Pa to 0.10 Pa, more specifically 0.05 Pa to 0.09 Pa.

[0050] In one embodiment, the colloidal silica may have a very low viscosity of 1.0 to 7.0 mPa·s, specifically 1.0 to 6.0 mPa·s, more specifically 1.0 to 5.0 mPa·s, measured under the following conditions. Colloidal silica having such low viscosity has small interparticle interactions and low flow resistance, so it can maintain excellent dispersibility even under high shear conditions.

[0051] Conditions: Temperature of 20℃, 20 wt% colloidal silica aqueous dispersion, 100 s -1 shear rate

[0052] As a practical example, the average particle size (D) of colloidal silica 50 When ) is 30 to 100 nm, 100 s -1 The viscosity of colloidal silica at a shear rate may be 1.0 to 5.0 mPa·s, specifically 2.0 to 5.0 mPa·s, more specifically 2.5 to 5.0 mPa·s, and even more specifically 3.0 to 4.5 mPa·s. As another substantial example, the average particle size (D) of the colloidal silica 50When ) is 100 to 250 nm, 100 s -1 The viscosity of colloidal silica at a shear rate may be 1.0 to 5.0 mPa·s, specifically 1.0 to 4.5 mPa·s, more specifically 1.5 to 4.0 mPa·s, even more specifically 1.5 to 3.5 mPa·s, and even more specifically 2.0 to 3.5 mPa·s.

[0053] In one embodiment, the average particle size (D of colloidal silica) 50 ) may be 30 to 250 nm, specifically 30 to 200 nm, more specifically 40 to 150 nm, and even more specifically 50 to 130 nm. As a substantial example, the average particle size (D) of colloidal silica. 50 ) can be 30 to 100 nm, 40 to 90 nm, 45 to 90 nm, 50 to 85 nm, or 50 to 80 nm. Such sizes are advantageous as they can significantly reduce the scratch rate. As a practical example, the average particle size (D) of colloidal silica 50 ) can be 100 to 250 nm, 100 to 200 nm, 105 to 150 nm, 105 to 145 nm, or 110 to 145 nm. Such sizes are advantageous as they can improve the polishing speed along with a low scratch rate. At this time, D 50 represents the cumulative volume median diameter.

[0054] In one embodiment, in the XPS spectrum of colloidal silica, the ratio (I1 / I2) of the intensity of the first peak (I1) and the intensity of the second peak (I2) may be 1.10 to 5.00, specifically 1.10 to 4.00, 1.10 to 3.50, 1.10 to 3.00, 1.10 to 2.50, 1.10 to 2.00, or 1.10 to 1.50. Alternatively, the ratio of the intensity (I1 / I2) may be 1.10 to 5.00, specifically 1.30 to 4.50, 1.30 to 4.00, 1.30 to 3.50, 1.30 to 3.00, 1.30 to 2.50, or 1.30 to 2.30. Based on colloidal silica of the same size category, if the ratio of XPS strengths (I1 / I2) is too low, there is a risk of reduced polishing speed, and if the ratio of XPS strengths (I1 / I2) is excessively high, there is a risk of increased scratch rate. Strength ratios of 1.10 to 2.50, 1.10 to 2.00, or 1.10 to 1.50 are the D of the colloidal silica 50 When this is 30 to 100 nm, it may be a strength ratio favorable for improving polishing speed and suppressing scratch occurrence, and a strength ratio of 1.30 to 3.50, 1.30 to 3.00, 1.30 to 2.50, or 1.30 to 2.30 is D of colloidal silica 50 When this is 100 to 250 nm, it may be a strength ratio that is advantageous for improving polishing speed and suppressing scratch occurrence.

[0055] In one embodiment, the colloidal silica is at 550 ± 70 cm⁻¹ of the Raman scattering spectrum of the colloidal silica. -1 The wavenumber range, specifically 500 to 610 cm -1 The wavenumber range, more specifically 550 to 610 cm -1 The wavenumber range, more specifically 580 to 610 cm -1 The wavenumber range, more specifically 590 to 610 cm -1It may not contain a D2 scattering peak in the wavenumber region.

[0056] The D2 scattering peak may be a peak derived from a vibration mode caused by a ring structure formed by the ternary bonding of the SiO2 unit structure, which is the basic bonding structure contained within the silica. Colloidal silica according to one embodiment substantially does not exhibit a D2 scattering peak in the Raman spectrum, so ring structures formed by high free energy ternary bonds may not be substantially contained within the colloidal silica or may be contained in very small amounts. Accordingly, structural defects and strain within the silica are small, so the colloidal silica can have a low free energy and a significantly stable structure.

[0057] The BET specific surface area of ​​the colloidal silica may be 30 to 150 m² / g. In one embodiment, the BET specific surface area of ​​the colloidal silica may be 40 to 100 m² / g, 40 to 90 m² / g, 40 to 85 m² / g, 50 to 85 m² / g, or 50 to 80 m² / g. In one embodiment, the BET specific surface area of ​​the colloidal silica may be 30 to 80 m² / g, 30 to 70 m² / g, 30 to 60 m² / g, 30 to 50 m² / g, 30 to 45 m² / g, or 30 to 40 m² / g. As a specific example, D of the colloidal silica 50 When this is 30 to 100 nm, a low specific surface area of ​​40 to 85 m² / g, 50 to 85 m² / g, or 50 to 80 m² / g and D of colloidal silica 50 When the length is 100 to 250 nm, it can have a low specific surface area of ​​30 to 60 m² / g, 30 to 50 m² / g, 30 to 45 m² / g, or 30 to 40 m² / g.

[0058] In one embodiment, D of colloidal silica 50 / (D 90 -D 10) can be 1.10 to 4.00. Specifically, D 50 / (D 90 -D 10 ) may be 1.20 to 3.50, more specifically 1.30 to 3.00. As a substantial example, D 50 / (D 90 -D 10 ) may be 1.30 to 1.80 or 1.80 to 3.00. D 50 / (D 90 -D 10 ) relates to the particle size distribution of colloidal silica, and can have a larger value as the particles have a more uniform size. D exceeding 1 50 / (D 90 -D 10 ) may mean that colloidal silica has an extremely uniform size, practically a single size distribution.

[0059] In one embodiment, the colloidal silica is a colloidal factor (C of Formula 1 below) f ) can satisfy 0.60 to 2.50.

[0060] (Equation 1)

[0061]

[0062] In Equation 1, I1 represents the intensity of the first peak with a binding energy of 533±0.5 eV in the XPS spectrum of colloidal silica, I2 represents the intensity of the second peak with a binding energy of 534±0.5 eV, and D 50 , D 10 , D 90 represents the particle diameter (nm) at 50%, 10%, and 90% of the cumulative volume in the cumulative volume size distribution of colloidal silica.

[0063] C f is an indicator that can indicate the colloidal stability and abrasive properties of colloidal silica combined with particle dispersion and surface characteristics. C fIf α is low at 0.60 or lower, abrasive properties may decrease, and if Cf exceeds 2.50, the scratch rate may increase significantly. As a favorable example, C f may be 0.60 to 2.30, specifically 0.65 to 2.10. As a substantial and advantageous example, D of colloidal silica 50 When this is 30 to 100 nm, C f It may be 0.65 to 2.00, 0.70 to 2.00, 0.70 to 1.80, 0.70 to 1.60, 0.70 to 1.50, or 0.75 to 1.50. As a substantial and advantageous example, D of colloidal silica 50 When this is 100 to 250 nm, C f It may be 0.60 to 2.30, 0.65 to 2.20, 0.65 to 2.15, 0.70 to 2.15, 0.75 to 2.15, 0.80 to 2.15, or 0.85 to 2.15.

[0064] In one embodiment, in the X-ray diffraction pattern of colloidal silica, a diffraction peak due to an amorphous structure is located in the 2θ range of 23.5±1˚, and the full width at half maximum (FWHM) of the diffraction peak may be 8.00 to 11.00°, specifically 8.20 to 11.00°.

[0065] In addition, in the X-ray diffraction pattern of colloidal silica, there may be a single diffraction peak in the 2θ range of 10 to 40˚, and the single diffraction peak may be a peak due to the aforementioned amorphous structure. At this time, the statement that the diffraction peak is located in a certain 2θ range may mean that the center of the diffraction peak is located in a certain 2θ range, and the center of the diffraction peak may mean the 2θ value at the peak maximum.

[0066] The X-ray diffraction characteristics of the aforementioned colloidal silica indicate that the colloidal silica is amorphous silica when analyzed by macroscopic structure. Although the colloidal silica according to one embodiment is amorphous silica when analyzed by macroscopic structure, it has a first peak and a second peak at 533±0.5 eV and 534±0.5 eV, respectively, in the XPS spectrum, and the intensity of the first peak is greater than the intensity of the second peak. A crossover occurs between the storage factor (G') and the loss factor (G˝) at a shear strain of 2.00% to 5.00%, and the maximum storage factor (G') in the region of 0.10% to 0.20% shear strain is 0.80 Pa or less, so it can exhibit an improved polishing rate with excellent structural stability and robustness, and together with excellent colloidal stability, it can exhibit a significantly low scratch rate. Along with this, the intensity ratio (I1 / I2) of the aforementioned first peak and second peak and the aforementioned significantly small |G˝ HSS - G˝ LSS When the value is satisfied, colloidal silica can exhibit significantly improved polishing speed by having amorphous characteristics and hardness suitable for abrasives, and at the same time, exhibit excellent dispersibility even under polishing conditions, thereby possessing extremely excellent scratch resistance.

[0067] In one embodiment, in the small-angle X-ray scattering (SAXS) spectrum of colloidal silica, 1.55 ± 0.15 Å -1 A scattering peak may be located at the scattering vector of . In this case, the SAXS spectrum of colloidal silica is at the scattering vector (q, Å -1 This is the spectrum of scattering intensity (I(q)) according to ). Specifically, the SAXS spectrum is from 1.40 to 1.70 Å -1 The scattering vector region of, specifically 1.45 to 1.65 Å -1 The scattering vector region of, more specifically 1.50 to 1.65 Å -1A scattering peak may be located in the scattering vector region of . In this case, "the scattering peak is located in a certain region of the scattering vector" means that the center of the scattering peak is located in that region, with the scattering vector value at the maximum intensity of the scattering peak as the center of the scattering peak. 1.55±0.15 Å -1 The presence of a scattering peak (hereinafter referred to as the Hq peak) located in the scattering vector region can indicate the aggregation and uniformity of silica nanodomains within the particles of colloidal silica, as well as the inter-particle uniformity of the colloidal silica. Specifically, a strong Hq peak may imply that silica nanodomains are uniformly condensed and highly densified within the particles, and that the colloidal silica possesses uniform physical properties without inter-particle variation. The intensity of the Hq peak is the scattering intensity I at the peak bottom point of the Hq peak. S The maximum scattering intensity I of the and Hq peaks M Liver intensity ratio I M / I S It can be represented by the intensity of the Hq peak I M / I S may be 1.50 to 4.00, specifically 1.70 to 3.50, more specifically 2.00 to 3.00, even more specifically 2.10 to 2.70, and even more specifically 2.20 to 2.60. It satisfies the ratio (I1 / I2) between the intensities of the first and second peaks mentioned above in the XPS spectrum, a crossover between the storage modulus and the loss modulus (G˝) occurs at small shear strains of 2.00% to 5.00%, the maximum value of the storage modulus (G') in the low shear strain region (0.10% to 0.20% region) is small at 0.80 Pa or less, and the aforementioned significantly small |G˝ HSS - G˝ LSS Colloidal silica having a | value and the intensity of the aforementioned Hq peak can exhibit significantly improved in-plane polishing uniformity, along with the aforementioned excellent polishing speed, dispersion stability, and scratch resistance.

[0068] In one embodiment, colloidal silica may be produced in a continuous flow reactor. Specifically, the continuous flow reactor may be a continuous microtube flow reactor. FIG. 1 is a transmission perspective view illustrating a continuous microtube flow reactor used for producing colloidal silica according to one embodiment. As shown in FIG. 1, the microtube flow channel (110) may have a three-dimensional coil (100) structure in which it is wound in a coil shape around a virtual cylinder (not shown) having a constant diameter. In this microtube of the three-dimensional coil (100) structure, centrifugal force and internal force may be applied to the reaction liquid flowing inside the microtube continuously from the start of the reaction to the end of the reaction, and a secondary flow of vortex / circulation flow may be generated.

[0069] In detail, in the three-dimensional coil (100) structure, the microtube providing the flow path may have a double (double) structure in which it has an inlet (310, 320) at the top of the three-dimensional coil (100), is wound down into a virtual cylinder in a clockwise or counterclockwise direction to reach the bottom, and from the bottom, is wound up again into a virtual cylinder in the same direction (clockwise or counterclockwise direction) to have an outlet (330) at the top. This double (double) structure is advantageous because it can generate additional flow due to gravity during the mid-to-late stages of the reaction. At this time, as in the example shown in FIG. 1, the microtube forming the three-dimensional coil (100) structure may be physically supported by a support member (200).

[0070] The inner diameter of the microtube (diameter of the flow path) may be 1 to 10 mm, the coil diameter (diameter of the virtual cylinder) may be 100 to 600 mm, and the volume of the reaction space provided by the coiled microtube (flow path width based on the inner diameter of the microtube x total length of the microtube) may be 500 ml to 3000 ml.

[0071] An inlet (310, 320) capable of injecting a reaction solution may be located at one end of the microtube, and an outlet (330) through which the reaction solution passing through the microtube is discharged may be located at the other end of the microtube. At this time, as illustrated in FIG. 1, the inlet (310, 320) and the outlet (330) may each be located at the upper end of the three-dimensional coil (100). Specifically, a first inlet (310) may be located at one end of the microtube, and a second inlet (320) may be located in a concentric structure surrounding the first inlet (310). The inlet of such a concentric structure is a structure in which the substance(s) injected through the inlet(s) are injected and flow in a co-flow manner. Alternatively, a first inlet may be located at one end of the microtube, and a second inlet may be located in a microtube region adjacent to the one end. These separate first and second inlets are structured so that material(s) are injected and flow through the inlet(s) in an inline mixing manner.

[0072] Additionally, as shown in the example illustrated in FIG. 1, the continuous microtube flow reactor may further include a static mixer (400) for uniform mixing of fluids as needed, and the static mixer (400) may be provided in a flow path area adjacent to the inlet. The static mixer is sufficient if it is an element structure commonly used to promote mixing of fluids flowing through a tube, such as a spiral element, a grid element, a blocking plate element, or a twist element. The example in FIG. 1 is an example in which a twist element, in which plates twisted 180˚ are repeatedly connected, is provided as the static mixer (400).

[0073] A continuous microtube flow reactor may further include a heating member (not shown) capable of heating and maintaining the reaction liquid inside the microtube to a desired temperature by contacting the inner side of the coil, the outer side of the coil, or both the inner and outer sides of the coil in a three-dimensional coil (100) structure. The heating member may include a conventional heating element that generates heat by Joule heating, and as a practical example, may include a sheet-type heating element.

[0074] In the same manner as illustrated in FIG. 1, a first liquid containing deionized water, ethanol, and ammonia water, which is an alkali catalyst, can be injected through the first injection port (310) located on the inner side of the injection port, and a second liquid containing tetraethyl orthosilicate (TEOS), which is a liquid organic silane precursor, can be injected through the second injection port (320) located on the outer side.

[0075] Specifically, D of 30 to 100 nm capable of exhibiting improved scratch resistance along with a high polishing speed 50 When preparing colloidal silica having the above, the mass ratio of deionized water : ethanol : ammonia water in the first solution may be 100 : 90 to 110 : 5 to 15, specifically 100 : 95 to 100 : 8 to 12, and the concentration of ammonia water may be 25 to 35 wt%, specifically 27 to 32 wt%. The ratio of the volume of the first solution and the second solution injected per unit time through the first inlet (310) and the second inlet (320) may be 100 : 7 to 15. At this time, the volume of the reaction space can be controlled so that the time the injected first solution and second solution remain in the flow path within the continuous microtube-type flow reactor is 5 to 20 minutes, specifically 7 to 17 minutes, and the temperature of the reaction solution in the flow path can be controlled to 50 to 65°C, specifically 55 to 60°C.

[0076] Specifically, D of 100 to 250 nm capable of exhibiting a higher polishing speed along with excellent scratch resistance 50When preparing colloidal silica having the above, the mass ratio of deionized water : ethanol : ammonia water in the first solution may be 100 : 190 to 220 : 10 to 20, specifically 100 : 195 to 215 : 10 to 15, and the concentration of ammonia water may be 25 to 35 wt%, specifically 27 to 32 wt%. The ratio of the volume of the first solution and the second solution injected per unit time through the first inlet (310) and the second inlet (320) may be 100 : 6 to 15. At this time, the volume of the reaction space can be controlled so that the time the injected first solution and second solution remain in the flow path within the continuous microtube-type flow reactor is 5 to 20 minutes, specifically 6 to 15 minutes, and the temperature of the reaction solution in the flow path can be controlled to 50 to 70°C, specifically 55 to 65°C.

[0077] A colloidal silica aqueous dispersion can be prepared by distilling off ethanol from a colloidal silica dispersion discharged through an outlet and replacing the solvent with deionized water.

[0078] Another aspect of the present invention provides a chemical mechanical polishing composition comprising the aforementioned colloidal silica as abrasive particles. In this case, the chemical mechanical polishing composition may be a composition for polishing silicon or silicon oxide. The aforementioned colloidal silica has properties that are highly suitable for rapidly polishing silicon or silicon oxide without scratching, but the polishing target is not necessarily limited to silicon or silicon oxide. The aforementioned colloidal silica may also be utilized as abrasive particles for polishing metal films or abrasive particles for polishing organic films. In this case, the metal film may include a metal film containing copper and / or tungsten, etc., and the organic film may include a carbon film or an organic hard mask. The carbon film may include an amorphous carbon film (ACL), a diamond-like carbon film (DLC), a spin-on carbon film (SoC), etc., but is not limited thereto.

[0079] Colloidal silica particles contained in the chemical mechanical polishing composition may be 0.1 to 40 weight% with respect to the total weight of the composition, specifically 0.2 to 30 weight%, and more specifically 0.3 to 25 weight%.

[0080] In one embodiment, the chemical mechanical polishing composition may further include one or more selected from the group consisting of water-soluble polymers, glycol-based compounds, pH adjusters, chelating agents, surfactants, and basic compounds.

[0081] As water-soluble polymers, water-soluble polysaccharides, water-soluble polyacrylate polymers, water-soluble vinyl polymers, and water-soluble polyether polymers may be selected. Specific examples include, but are not limited to, hydroxyethylmethylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, and polyethylene glycol. The water-soluble polymer may be included in an amount of 0.001 to 25 weight% based on the total weight of the chemical mechanical polishing composition, specifically 0.01 to 20 weight%, more specifically 0.05 to 10 weight%, and even more specifically 0.05 to 5 weight%, but is not limited thereto.

[0082] Examples of glycol-based compounds include polyethylene glycol, ethylene glycol, propylene glycol, etc., but are not limited thereto. The glycol-based compound may be present in an amount of 0.001 to 15 weight% with respect to the total weight of the chemical mechanical polishing composition, specifically 0.01 to 15 weight%, more specifically 0.01 to 10 weight%, and even more specifically 0.01 to 5 weight%, but is not limited thereto.

[0083] Inorganic acids or organic acids such as nitric acid, sulfuric acid, phosphoric acid, acetic acid, and citric acid may be used as acidic pH adjusters, and ammonium hydroxide, sodium hydroxide, triethanolamine, and tetramethylammonium hydroxide may be used as basic pH adjusters, but are not limited thereto. The pH of the chemical mechanical polishing composition can be adjusted to 2 to 11 by a pH adjuster.

[0084] Chelating agents may include amino acid-based chelating agents, carboxylic acid-based chelating agents, polyamine-based chelating agents, etc. Representative examples include glycine, aspartic acid, glutamic acid, citric acid, malic acid, tartaric acid, succinic acid, oxalic acid, ethylenediaminetetraacetic acid (EDTA), etc., but are not limited thereto. The chelating agent may be present in an amount of 0.001 to 15 weight% based on the total weight of the chemical mechanical polishing composition, specifically 0.001 to 10 weight%, more specifically 0.005 to 5 weight%, and even more specifically 0.01 to 3 weight%, but is not limited thereto.

[0085] Examples of surfactants include nonionic surfactants, anionic surfactants, and silicone-based surfactants. Representative examples include polyethylene oxide, polyoxyethylene oleyl ether, polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monooleate, sodium dodecyl sulfate, sodium salt of dodecinebenzenesulfonic acid, sodium salt of oleate, lauryl sulfate, polydimethylsiloxane, polyoxyethylene-linked polysiloxane, and amino-functionalized polysiloxane, but are not limited thereto. The surfactant may be present in an amount of 0.001 to 5 weight% based on the total weight of the chemical mechanical polishing composition, specifically 0.001 to 3 weight%, and more specifically 0.001 to 2 weight%, but is not limited thereto.

[0086] The above basic compound may be one or more selected from the group consisting of ammonia, amine-based compounds, alkali metal hydroxides, alkaline earth metal hydroxides, quaternary ammonium compounds, and amine-based coupling agents. The above basic compound may be 0.0001 to 5 weight% with respect to the total weight of the chemical mechanical polishing composition, and specifically may be included in an amount of 0.001 to 2 weight%.

[0087] The present invention will be described in detail below through examples. However, it should be noted that the examples described below are intended merely to illustrate and embody the present invention and are not intended to limit the scope of the present invention. This is because the scope of the present invention is determined by the matters described in the patent claims and matters reasonably inferred therefrom.

[0088] (Example 1)

[0089] Colloidal silica was prepared using a continuous tubular reactor as shown in Fig. 1. The material of the tube was PFA (perfluoroalkoxyalkane), a fluorine-based resin, and a static mixer was placed inside to allow the liquid to be mixed within the tube. The temperature of the continuous tubular reactor was maintained at 60°C, and the residence time was 12 minutes.

[0090] A reaction solution (Solution 1) was prepared by adding 1,590.4 g of an aqueous ammonia solution with a concentration of 29.1 wt% as an alkali catalyst to 17,269 g of deionized water and 16,855 g of ethanol as solvents.

[0091] A reaction solution prepared was injected through an inner inlet (first inlet) at the same-flow inlet of a continuous tubular reactor, and a tetraethyl orthosilicate (TEOS) liquid (second liquid) was injected through an outer inlet (second inlet). At this time, the first liquid was injected via a pump at a flow rate of 80 mL / min and the second liquid at a flow rate of 6 mL / min. The injected first and second liquids were mixed inside the tube of the continuous tubular reactor, and the reaction proceeded, and colloidal silica discharged after 30 minutes from the start of injection was continuously obtained.

[0092] The obtained colloidal silica dispersion was introduced into an evaporator, and ethanol was removed by reducing pressure (85°C, 70 mbar) until the concentration of the colloidal silica solid content reached 20 wt%. The pH of the dispersion from which the ethanol had evaporated was found to be 10.0. Subsequently, deionized water was introduced into the evaporator while maintaining the volume of the dispersion and heating to remove the remaining ethanol. The pH of the colloidal silica aqueous dispersion from which the ethanol had been removed was found to be 7.5.

[0093] (Example 2)

[0094] In Example 1, a reaction solution (Solution 1) was prepared by adding 1,266.7 g of an aqueous ammonia solution with a concentration of 29.1 wt% as an alkali catalyst to 9,290 g of deionized water and 19,149 g of ethanol as solvents, and the procedure was carried out in the same manner as in Example 1, except that Solution 1 was injected through a pump at a flow rate of 80 mL / min and Solution 2 at a flow rate of 6.6 mL / min, and the temperature of a continuous tubular reactor was maintained at 65°C.

[0095] (Example 3)

[0096] In Example 1, the procedure was carried out in the same manner as Example 1, except that the first solution was injected through a pump at a flow rate of 70 mL / min and the second solution at a flow rate of 10 mL / min.

[0097] (Example 4)

[0098] In Example 2, the procedure was carried out in the same manner as Example 2, except that the first solution was injected through a pump at a flow rate of 70 mL / min and the second solution at a flow rate of 10.5 mL / min.

[0099] (Example 5)

[0100] In Example 1, the procedure was carried out in the same manner as Example 1, except that the first solution was injected through a pump at a flow rate of 53.3 mL / min and the second solution at a flow rate of 4 mL / min.

[0101] (Example 6)

[0102] In Example 1, the procedure was carried out in the same manner as Example 1, except that the temperature of the continuous tubular reactor was maintained at 55°C and the first liquid and the second liquid were injected through a pump at a flow rate of 100 mL / min and 7.5 mL / min, respectively.

[0103] (Example 7)

[0104] In Example 2, the procedure was carried out in the same manner as Example 2, except that the first liquid was injected through a pump at a flow rate of 60 mL / min and the second liquid at a flow rate of 4.9 mL / min, respectively, and the temperature of the continuous tubular reactor was maintained at 55℃.

[0105] (Example 8)

[0106] In Example 2, the procedure was carried out in the same manner as Example 2, except that the first solution was injected through a pump at a flow rate of 120 mL / min and the second solution at a flow rate of 8 mL / min.

[0107] (Comparative Example 1)

[0108] 270 g of deionized water and 30 g of tetramethyl orthosilicate (TMOS) were added to a flask and stirred at room temperature. After carrying out the hydrolysis reaction for 1 hour while stirring at room temperature, a hydrolysis solution was prepared, and the pH of the hydrolysis solution was found to be 4.2.

[0109] 200 g of deionized water and 0.18 g of 1N-TMAH (tetramethylammonium hydroxide) were added to a flask equipped with a reflux head, and the mixture was heated. The change in pH was observed while slowly adding the hydrolysate to the heated solution. When the pH of the solution decreased to 6.2, 1N TMAH solution was slowly added again to adjust the pH to 8. While maintaining the pH at 8, 1N TMAH solution and the hydrolysate were slowly added simultaneously. After the addition of the hydrolysate was completed, the reaction was carried out for 4 hours, and after the reaction was terminated, the solution was coarsely filtered using a 90 μm mesh filter. The coarsely filtered colloidal silica dispersion was introduced into an evaporator, and methanol was removed by heating and concentrating until the concentration of colloidal silica solids reached 20 wt%. Subsequently, deionized water was added to the evaporator while maintaining the volume of the dispersion, and the mixture was heated to remove any remaining methanol. The colloidal silica dispersion from which methanol had been removed was filtered through a 3 μm membrane filter to finally obtain a colloidal silica dispersion.

[0110] (Comparative Example 2)

[0111] A reaction solution (first solution) was prepared by adding 10g of a 29.1 wt% ammonia solution as an alkali catalyst to 100g of deionized water and 100g of methanol as solvents.

[0112] A second solution was prepared by mixing 15g of methanol and 28g of tetramethyl orthosilicate (TMOS).

[0113] While maintaining the temperature of the first solution at 35°C, the second solution was slowly injected into the first solution over a period of 5 hours while stirring. The mixed solution was introduced into an evaporator and heated and concentrated until the concentration of colloidal silica solids reached 20 wt% to remove methanol. Subsequently, deionized water was introduced into the evaporator while heating to maintain the volume of the dispersion to remove residual methanol. The methanol-removed colloidal silica dispersion was filtered through a 3 μm membrane filter to finally obtain the colloidal silica dispersion.

[0114] (Comparative Example 3)

[0115] Comparative Example 2 was carried out in the same manner as Comparative Example 2, except that methanol was replaced with ethanol and tetraethyl orthosilicate (TEOS) was used instead of tetramethyl orthosilicate (TMOS).

[0116] Analysis and Evaluation Methods

[0117] For analysis requiring a powdered sample, colloidal silica prepared in the form of an aqueous dispersion was dried under reduced pressure at 70°C and 30 torr for 12 hours and used as a powdered sample.

[0118] X-ray Photoelectron Spectroscopy (XPS)

[0119] XPS spectra were obtained for the samples (powder form) of the Examples and Comparative Examples using an X-ray photoelectron spectrometer (AXIS Supra+, Kratos, UK). X-ray photoelectron spectroscopic analysis was performed based on ISO 10810, using micro-focused monochromated X-rays of micro-focused Al-Kα (1486.6 eV) as the light source, under conditions of a Rowland circle of 500 mm, power of 225 W, and emission current of 15 mA. The electron analyzer of the lens system was a spherical sector analyzer, the detector was a 128-channel Delay-Line Detector (DLD) with a Micro-Channel Plate (MCP), and the minimum analysis range was 15 μm, with 6000 cps @ 0.6 eV FWHM. After obtaining the XPS spectrum of colloidal silica by X-ray photoelectron spectroscopy, a baseline was established using a straight line connecting the start and end points of the peak located in the 528–540 eV region (XPS O 1s spectrum region) (linear method), and peak deconvolution was performed into two Gaussian subpeaks. The positions of the two subpeaks were in the ranges of 533±0.1 eV and 534±0.1 eV, and the R-squared value between the envelope formed by the combined subpeaks and the actual peaks was calculated. 2 Peak decomposition was performed so that the (coefficient of determination) had a value closest to 1.

[0120] X-ray Diffraction Analysis (XRD)

[0121] XRD diffraction patterns were obtained for the samples (powder form) of the examples and comparative examples using an X-ray diffraction analyzer (D8 Discover, Bruker). XRD analysis was performed using Cu-Kα as an X-ray source under conditions of 40 kV and 40 mA, with a scan step size of 0.05°, a scan speed of 5° / min, and a 2θ range of 5 to 80°.

[0122] Raman Spectroscopy

[0123] Spectra were obtained for the samples (powder form) of the Examples and Comparative Examples using a micro-Raman spectrometer (InVia basic, Renishaw). Specifically, Raman spectroscopic analysis was performed based on ASTM E1840 (calibration using standard materials), ASTM E2529 (resolution), and ASTM E2911 (intensity correction), with a measurement wavelength of 785 nm, an objective lens magnification of long focal X50, and a scan range of 4000–100 cm⁻¹. -1 It was performed under conditions of an exposure time of 10 seconds, a laser power of 100%, and 4 scans.

[0124] Small Angle X-ray Scattering (SAXS)

[0125] Small-angle X-ray scattering (SAXS) analysis (Xeuss 2.0, Xenocs) was performed on the samples of the examples and comparative examples.

[0126] Small-angle X-ray scattering analysis was performed based on ASTM E1521; 5 mg of the powdered sample was loaded into a quartz powder sample holder, and the sample-to-detector (SDD) distance (2.5 m) was 2.5 m. Cu Kα X-rays were used, and a standard beam (1–2 mm size) with a Gaussian beam profile was irradiated to obtain 0.003–3.700 Å. -1X-rays scattered in the range of scattering vectors (q) were detected. Absolute intensity correction was performed using a standard sample, and background correction was performed using an empty powder sample holder.

[0127] 1.55±0.15 Å in the scattering intensity I(q) spectrum as a function of scattering vector q -1 Check whether a scattering peak exists in the q region of, and if a scattering peak exists, 0.70 to 1.35 Å -1 After calculating the derivative of I(q) with respect to q in the region q, the scattering intensity (I) at the point where the derivative begins to increase continuously to a positive value. S ) and the maximum scattering intensity of the scattering peak (I M Using ), the intensity of the Hq peak (I M / I S ) was produced.

[0128] Dynamic Light Scattering (DLS)

[0129] Dynamic light scattering analysis was performed using a light scattering spectrometer (ELSZ-2000S, Otsuka) equipped with a semiconductor laser of 658 nm wavelength in a laser Doppler method system. The concentration of colloidal silica particles in deionized water was adjusted to 0.1 wt% and used as the analytical sample. Scattered light was detected by a detector (Avalanche photodiode, APD) positioned at 90° to the incident light source, and the particle distribution was calculated using a CONTIN routine.

[0130] Obtain a graph of colloidal silica particle size vs. volume fraction % through DLS, and D 10 , D 50 , D 90 After calculating, D 50 / (D 90 -D 10 ) calculated.

[0131] Nitrogen adsorption / desorption test

[0132] Nitrogen adsorption and desorption tests were performed on the samples (powder form) of the Examples and Comparative Examples. Nitrogen adsorption and desorption isotherms were measured using a specific surface area analyzer (ASAP2460M, Micromeritics) at a temperature of 77.3 K using liquid nitrogen as the adsorbed nitrogen gas. Subsequently, the BET specific surface area (m²) was calculated using the BET method from the nitrogen adsorption isotherm results in the relative pressure (P / P0) range of 0.02 to 0.30. 2 / g) was calculated.

[0133] Rheology analysis (G'-G˝ diagram)

[0134] Colloidal silica (20 wt% aqueous dispersion) prepared in the examples and comparative examples was used as the analytical sample. Diagrams of storage and loss factors according to shear strain (%) were based on ISO 3219 and measured (amplitude sweep) under the following conditions using a rheometer (MCR 302e, Antor Paar).

[0135] Sample: 20 wt% colloidal silica aqueous dispersion (pH 7.2)

[0136] Sample volume: 1.0 ml,

[0137] Temperature: 20℃,

[0138] Frequency: 1Hz,

[0139] Shear strain: 0.10%~100.00%

[0140] Measuring Plate: Cone-shaped plate (diameter 50 mm, inclination angle 1 degree, model CP50-1)

[0141] Rheology analysis (viscosity)

[0142] Colloidal silica (20 wt% aqueous dispersion) prepared in the examples and comparative examples was used as the analytical sample. Viscosity according to shear rate was measured under the following conditions (shear rate sweep) using a Rheometer (MCR 302e, Antor Paar) based on ISO 3219.

[0143] Sample: 20 wt% colloidal silica aqueous dispersion (pH 7.2)

[0144] Sample volume: 0.7 ml

[0145] Temperature: 20 ℃,

[0146] Shear rate: 0.1 s -1 ~ 1000 s -1

[0147] Measuring plate: Cone type (50mm, inclination 1°, CP-50-1)

[0148] Evaluation of polishing characteristics

[0149] Deionized water and nitric acid were added to the 20 wt% colloidal silica aqueous dispersion prepared in the examples and comparative examples to prepare a slurry with a colloidal silica concentration of 2 wt% and a pH adjusted to 2.5.

[0150] Subsequently, a silicon wafer (300 mm PETEOS Wafer) having a silicon oxide film formed thereon was polished using the following apparatus and conditions, and the polishing speed was calculated by comparing the thickness before and after polishing. After polishing, the number of scratches (total number of wafer scratches) occurring on the entire wafer area was measured using a wafer surface inspection system (LS-9300A, HITACHI), and the scratch level was evaluated as 1 if the number of scratches was 0 to 100, 2 if 100 to 300, 3 if 300 to 1,000, 4 if 1,000 to 10,000, and 5 if >10,000.

[0151] Evaluation Equipment: AP-300 (CTS)

[0152] PAD: IC-1070 (DOW)

[0153] Grinding conditions: 2.0 psi, Head: 87 rpm, Platen: 93 rpm,

[0154] Slurry flow rate: 250 ml / min

[0155] Grinding time: 60 sec

[0156] Thin film thickness measurement equipment: ST5030-SL (K-Mac)

[0157] Figure 2 is a transmission electron microscope image of the colloidal silica prepared in Example 1, and Figure 3 is a transmission electron microscope image of the colloidal silica prepared in Example 2. The physicochemical properties of the colloidal silica prepared in the examples and comparative examples are as shown in Table 1 below.

[0158] In Table 1 below, the XPS intensity ratio refers to the intensity ratio (I1 / I2) of the first peak located at a binding energy of 533±0.1 eV in the XPS spectrum (I1) and the second peak located at 534±0.1 eV (I2), and the intensity of one peak is the area intensity of the corresponding peak.

[0159] Colloidal Factor (C f ) is a parameter calculated from the analysis results of XPS and DLS as shown in Equation 1 below, and can be evaluated as an indicator of the colloidal stability and polishing properties of colloidal silica in a polishing composition by combining the dispersion characteristics and surface characteristics of the particles.

[0160] (Equation 1)

[0161]

[0162] D 50 , D 90 , D 10 I represents the diameter (nm) at 50%, 90%, and 10% of the cumulative volume calculated from the DLS analysis results, I1 is the intensity of the first peak located at a binding energy of 533±0.1 eV in the XPS spectrum, and I2 is the intensity of the second peak located at 534±0.1 eV in the XPS spectrum.

[0163] In Table 1 below, FWHM refers to the full width at half maximum (FWHM, °) of the diffraction peak due to the amorphous structure located at 2θ = 23.5 ± 1 ° in the X-ray diffraction pattern of colloidal silica. D2 is 590 to 610 cm⁻¹ in the Raman scattering spectrum measured by Raman spectroscopy. -1 It refers to the presence or absence of a Raman scattering peak observed in. In this case, as previously mentioned, whether a Raman scattering peak exists in a specific wavenumber region can be determined by whether the center of the Raman scattering peak is located in that wavenumber region, and the center of the Raman scattering peak refers to the wavenumber at the peak's maximum point (maximum intensity). γ c represents the shear strain (%) at the point where a crossover occurs between the storage factor and the loss factor in the diagram of G' and G˝ as a function of shear strain of colloidal silica, and G˝ c represents the loss factor (Pa) at the point where a crossover occurs between the storage factor and the loss factor, and △G˝ is the maximum loss factor value G˝ in the shear strain region of 0.10% to 1.00% in the diagram of G' and G˝ according to shear strain. LSS (Pa) and G˝, the maximum loss factor value in the shear strain region of 40.00% to 100.00% HSS (Pa) represents the absolute value of the difference, and G' m represents the maximum storage modulus value (Pa) in the shear strain range of 0.10% to 0.20%, and η is 100 s -1 It refers to the viscosity (mPa·s) at I M / I S is 1.55±0.15 Å in the SAXS spectrum of colloidal silica -1 Scattering intensity I at the peak start point of the scattering peak (Hq peak) located in the scattering vector region of S The maximum scattering intensity I of the and Hq peaks M It refers to the intensity ratio between. S BET represents the BET specific surface area (m² / g) of colloidal silica.

[0164] XPS intensity ratio S BET (m 2 / g)D 50 (nm)D 50 / (D 90 -D 10 )C f FWHMγ c G˝ c △G˝G' m ηD2I M / I S Example 1 1.4774.156.21.400.959.413.250.070.010.213.67X2.38 Example 2 2.0937.4118.51.860.899.183.510.060.080.652.63X2.29 Example 3 1.2654.174.91.351.079.43.200.070.01 0.24 3.31X2.51 Example 4 1.4 138.6 14 2.3 2.9 22.0 78.5 13.8 60.0 60.0 60.6 42.4 2X2.36 Example 5 1.1 27 5.0 67.9 1.4 61.3 0 10.8 3.2 30.0 70.0 10.2 24.3 7X2.26 Example 6 2.1 37 7.2 55.2 1.6 20.7 68.4 03.480.070.040.294.61X2.19 Example 73.4235.7114.02.890.848.484.660.080.130.733.25X2.12 Example 83.1534.4117.52.050.658.444.500.080.100.673.90O1.73 Comparative Example 10.8387.54 8.23.293.969.886.720.110.060.715.77X1.84 Comparative Example 23.52132.124.11.520.438.427.400.090.050.746.38O1.49 Comparative Example 30.9182.165.73.473.818.776.530.120.080.945.23O1.67

[0165] The polishing characteristics of the chemical mechanical polishing compositions using colloidal silica prepared in the examples and comparative examples as abrasive particles are as shown in Table 2 below.

[0166] Polishing Speed ​​(Å / min) Scratch Level Example 1 3771 Example 2 5582 Example 3 3811 Example 4 5972 Example 5 3581 Example 6 3942 Example 7 5793 Example 8 3512 Comparative Example 1 2904 Comparative Example 2 3015 Comparative Example 3 2544

[0167] As a result of testing with a single pass, it was found that the polishing rates of Examples 1 to 8 were at a level of 350 to 580 Å / min, whereas Comparative Examples 1 to 3 were at a level of 300 Å / min or less. In the scratch evaluation as well, Examples 1 to 8 showed good results, while the Comparative Examples showed average results, and Comparative Example 2 showed particularly poor results. As described above, the present invention has been explained by limited examples, but this is provided only to aid in a more comprehensive understanding of the present invention, and the present invention is not limited to the above examples. A person skilled in the art to which the present invention belongs can make various modifications and variations from this description. Therefore, the concept of the present invention should not be limited to the described examples, and all things equivalent to or having equivalent variations to the claims set forth below, as well as the claims themselves, shall be considered to fall within the scope of the concept of the present invention.

Claims

In colloidal silica, The above colloidal silica has a first peak at 533±0.5 eV and a second peak at 534±0.5 eV in an XPS spectrum measured by X-ray photoelectron spectroscopy (XPS), and the intensity of the first peak is greater than the intensity of the second peak, and Colloidal silica, wherein, among the storage modulus (G', Pa) and loss modulus (G˝, Pa) according to shear strain (%) obtained under the following conditions, a crossover occurs between the storage modulus (G') and the loss modulus (G˝) at a shear strain of 2.00% to 5.00%, and the maximum storage modulus (G') in the region of a shear strain of 0.10% to 0.20% is 0.80 Pa or less. Conditions: Temperature 20℃, 20 wt% colloidal silica aqueous dispersion, 1 Hz frequency, 0.10%–100.00% shear strain sweep In Article 1, The loss coefficient (G˝) at the point where a crossover occurs between the above storage coefficient and the loss coefficient c ) is colloidal silica with a content of 0.10 Pa or less. In Article 1, G˝, the maximum loss factor value in the shear strain region of 0.10% to 1.00% LSS and G˝, the maximum loss factor value in the shear strain region of 40.00% to 100.00% HSS Colloidal silica having an absolute difference of 0.10 Pa or less. In Article 1, The above colloidal silica is colloidal silica having a viscosity of 1.0 to 7.0 mPa·s measured under the following conditions. Conditions: Temperature of 20℃, 20 wt% colloidal silica aqueous dispersion, 100 s -1 shear rate In Article 1, Colloidal silica, wherein the ratio (I1 / I2) of the intensity of the first peak (I1) and the intensity of the second peak (I2) of the XPS spectrum is 1.10 to 5.

00. In Article 1, In the spectrum measured by the above Raman spectroscopy, 550±70 cm⁻¹ -1 Colloidal silica that does not contain a D2 scattering peak in the wavenumber region. In paragraph 1, The BET specific surface area of ​​the above colloidal silica is 30.0 to 150.0 m² 2 / g, colloidal silica. In paragraph 1, Average particle size (D) of the colloidal silica in the aqueous dispersion 50 ) is colloidal silica with a thickness of 30.0 to 250.0 nm. In paragraph 1, D of the above colloidal silica 50 / (D 90 -D 10 Colloidal silica, with a content of 1.10 to 4.

00. In paragraph 1, The above colloidal silica is a colloidal factor (C) of Formula 1 below. f Colloidal silica satisfying ) 0.60 to 2.

50. [Equation 1] (In Equation 1 above, I1 represents the intensity of the first peak with a binding energy of 533±0.5 eV in the XPS spectrum, and I2 represents the intensity of the second peak with a binding energy of 534±0.5 eV.) In paragraph 1, The above colloidal silica is colloidal silica produced in a continuous flow reactor. A chemical mechanical polishing composition comprising colloidal silica according to any one of claims 1 to 11 as abrasive particles. In Paragraph 12, A chemical mechanical polishing composition comprising one or more selected from the group consisting of water-soluble polymers, glycol-based compounds, pH adjusters, chelating agents, surfactants, and basic compounds.

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