KR102513110B1 - Preparing method for ultra high purity colloidal silica particle and ultra high purity colloidal silica particle prepared by the same - Google Patents

Abstract

The present invention relates to a method for producing ultra-high purity colloidal silica particles and ultra-high purity colloidal silica particles produced thereby. preparing; preparing a reaction solution by dropping silicon alkoxide into the basic material; aging the reaction solution; heating the aged reaction solution; and concentrating the heated reaction solution using a vacuum concentrator.

Description

Method for producing ultra-high purity colloidal silica particles and ultra-high purity colloidal silica particles produced thereby

The present invention relates to a method for preparing ultra-high purity colloidal silica particles and ultra-high purity colloidal silica particles produced thereby.

Colloidal silica obtained by an ion exchange method using water glass (sodium silicate) as a raw material has been generally used in a wide range of industrial fields for a long time.

In the manufacturing method, colloidal silica is produced by passing water glass through an ion exchange resin to remove sodium and then subjecting it to hydrolysis and condensation. However, although this method has the advantage of being inexpensive, it is difficult to control the dispersion form and average particle size of colloidal silica particles, and above all, it contains a large amount of metal impurities contained in silica sand, a starting material for water glass, and has limitations in ion removal. There is a disadvantage in that the purity of the colloidal silica prepared using the same is low.

With the recent development of the semiconductor field, colloidal silica used for CMP polishing of silicon wafers and semiconductor devices and ultra-high purity colloidal silica containing less metal impurities are required.

Therefore, in order to avoid mixing of basic metals in raw materials and processes, the use of ultra-high purity silica produced by the stover method using alkoxy silane as a raw material in semiconductor processes is gradually increasing. In particular, in the final process of a 300 mm wafer, it aims to have no scratches because it has high flatness. For this purpose, a high concentration of colloidal silica including silica particles having a small particle diameter is required.

Currently, ultra-high purity colloidal silica particles in most of the semiconductor market are exclusively sold by Japan's FUSO, and TMOS (TetraMethylOrthoSilicate) is used as the main raw material. However, when using TMOS, the alcohol-based compound generated in the colloidal silica synthesis step is methanol, which has problems with environmental contamination and careless handling that can lead to blindness or death, so its use in Korea is extremely limited.

Therefore, there is an urgent need for a method for producing high-purity silica particles that is easy to handle and use, does not cause environmental pollution, and can obtain ultra-high-purity products.

The present invention is to solve the above-mentioned problems, and an object of the present invention is, a method for producing ultra-high purity colloidal silica particles that are easy to handle and use, do not cause environmental pollution, and can obtain ultra-high purity fine particles, and It is to provide ultra-high purity colloidal silica particles produced thereby.

However, the problem to be solved by the present invention is not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

A method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention includes preparing a basic material; preparing a reaction solution by dropping silicon alkoxide into the basic material; aging the reaction solution; heating the aged reaction solution; and concentrating the heated reaction solution using a vacuum concentrator.

In one embodiment, the preparing of the basic material may include a basic catalyst and water, or basic catalyst seed particles and water.

In one embodiment, the basic catalyst seed particles may be 1% to 5% by weight of the basic material, and the particle size of the seed particles may be 40 nm or less.

In one embodiment, the basic catalyst is ammonia, methyl amine, ethyl amine, n-propyl amine, n-butyl amine ), dimethyl amine, dietyl amine, dipropyl amine, dibutyl amine, trimethyl amine, trietyl amine, tripropyl It may contain at least one selected from the group consisting of amine (tripropyl amine), tributyl amine (tributyl amine) and ammonium hydroxide (ammonium hydroxide).

In one embodiment, the basic material may have a pH of 7 to 10.

In one embodiment, in the step of preparing the basic material, the temperature of the basic material may be 60 ℃ to 85 ℃.

In one embodiment, the silicon alkoxide is tetraethylorthosilicate (TEOS), 3-mercaptopropyltrimethoxysilane (MPTMS), phenyltrimethoxysilane (PTMS), vinyltrimethoxysilane (VTMS) , Methyltrimethoxysilane (MTMS), 3-aminopropyltrimethoxysilane (APTMS), 3-glycidyloxypropyltrimethoxysilane (GPTMS), (3-trimethoxysilyl)propylmethacrylate ( TMSPMA), 3-mercaptopropyltrimethoxysilane (MPTMS) and 3- (trimethoxysilyl) propyl isocyanate (TMSPI) may include at least one selected from the group consisting of.

In one embodiment, the step of preparing a reaction solution by dropping silicon alkoxide into the basic material may be adjusting the temperature of the reaction solution to 60 °C to 85 °C.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide on the basic material, when the basic material includes a basic catalyst and water, the dropping rate of the silicon alkoxide is 0.333 ml/min to 3.333 ml/min. min, and the dropping time may be 4 to 12 hours.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide to the basic material, when the basic material includes basic catalyst seed particles and water, the dropping rate of the silicon alkoxide is 0.3 ml/min to 4 ml/min, and the dropping time may be 4 to 12 hours.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide on the basic material, the basic catalyst may be 1% to 4% by weight based on the weight of the silicon alkoxide.

In one embodiment, the aging of the reaction solution may be performed at a temperature of 60 °C to 85 °C for 1 hour to 5 hours.

In one embodiment, the heating step is a step of heating the aged reaction solution.

In one embodiment, the heating step may remove a basic catalyst and an alcohol-based compound generated during the synthesis process.

In one embodiment, the step of heating the aged reaction solution may be to heat the temperature of the reaction solution to 99 ℃.

In one embodiment, the step of concentrating the heated reaction solution using a vacuum concentrator may include adding distilled water three times or more of the heated reaction solution and concentrating the heated reaction solution to a silica concentration of 10% to 25% by weight. .

Ultra-high purity colloidal silica particles according to another embodiment of the present invention are prepared by a method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention.

In one embodiment, the ultra-high purity colloidal silica particles may have a particle diameter of 10 nm to 100 nm.

In one embodiment, the ultra-high purity colloidal silica particles may have a contact angle with respect to water of 100 ° to 170 °.

In one embodiment, the ultra-high purity colloidal silica particles may satisfy Equation 1 below:

[Equation 1]

D ₁ /D ₂ ≤ 1.6

(D ₁ is the particle size value measured using DLS equipment, D ₂ is the value obtained by converting the specific surface area measured using BET equipment into particle size).

The method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention is a method in which silicon alkoxide is directly dropped onto a basic catalyst without the need for a separate alcohol addition and alcohol recollecting device, and is dense and stable with a size of 10 nm to 100 nm. These excellent high-purity colloidal silica particles can be produced.

Ultra-high-purity colloidal silica particles according to an embodiment of the present invention are composed of an aqueous dispersion of ultra-high-purity silica and contain a very small amount of metal ions and organic base compounds.

1 is a flow chart of a method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention.
2 is a TEM image of colloidal silica particles according to Example 1 of the present invention.
3 is a TEM image of colloidal silica particles according to Example 2 of the present invention.
4 is a TEM image of colloidal silica particles according to Example 3 of the present invention.
5 is a TEM image of colloidal silica particles according to Example 4 of the present invention.
6 is a TEM image of colloidal silica particles according to Example 5 of the present invention.
7 is a TEM image of colloidal silica particles according to Example 6 of the present invention.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, since various changes can be made to the embodiments, the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents or substitutes to the embodiments are included within the scope of rights.

Terms used in the examples are used only for descriptive purposes and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as "include" or "have" are intended to designate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which the embodiment belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present application, they should not be interpreted in an ideal or excessively formal meaning. don't

In addition, in the description with reference to the accompanying drawings, the same reference numerals are given to the same components regardless of reference numerals, and overlapping descriptions thereof will be omitted. In describing the embodiment, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the embodiment, the detailed description will be omitted.

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, order, or order of the corresponding component is not limited by the term.

Components included in one embodiment and components having common functions will be described using the same names in other embodiments. Unless stated to the contrary, descriptions described in one embodiment may be applied to other embodiments, and detailed descriptions will be omitted to the extent of overlap.

Hereinafter, the method for producing ultra-high purity colloidal silica particles according to the present invention and the ultra-high purity colloidal silica particles prepared thereby will be described in detail with reference to Examples and drawings. However, the present invention is not limited to these examples and drawings.

A method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention includes preparing a basic material; preparing a reaction solution by dropping silicon alkoxide into the basic material; aging the reaction solution; heating the aged reaction solution; and concentrating the heated reaction solution using a vacuum concentrator.

Conventionally, when reacting silica particles using silicon alkoxide, mixing and contamination of basic metals such as sodium can be avoided, but the growth rate is very fast in the process of controlling the shape or size of the particles, resulting in a stable structure of silica particles. There was a problem that particles could not be obtained. In addition, it is a batch type in which components such as alcohol solvent, silicon alkoxide, catalyst, and water are adjusted to suit the molar ratio and injected almost all at once, followed by reaction and maturation, so that slight variations in process conditions can be avoided. There was a high probability that defects could occur when applied to mass production due to uneven particle growth or limitations in controlling unreacted materials. In addition, alcohol was additionally used as a solvent to dilute the silicon alkoxide.

However, since the present invention does not use alcohol in addition to commercial high-purity silicon alkoxide, the production cost can be reduced, and the process time for extracting and recovering alcohol generated during the reaction can be shortened to achieve the final goal of aqueous dispersion. There are advantages to being

1 is a flow chart of a method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention.

Referring to FIG. 1, the method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention includes basic material preparation step 110, reaction solution preparation step 120, aging step 130, heating step ( 140) and a concentration step (150).

In one embodiment, the step 110 of preparing the basic material may include a basic catalyst and water, or basic catalyst seed particles and water.

In one embodiment, the basic catalyst seed particles may include seed particles in the basic catalyst.

In one embodiment, the basic catalyst seed particles may be 1% to 5% by weight of the basic material. When the amount of the basic catalyst seed particles is less than 1% by weight or greater than 5% by weight, the generation of unreacted particles may increase. Preferably, the seed particles may be 3% by weight of the basic material.

In one embodiment, the particle diameter of the seed particle may be 40 nm or less. 40 nm or more is also possible, but the seed particles have a maximum growth of 40 nm during the reaction.

In one embodiment, the basic catalyst is ammonia, methyl amine, ethyl amine, n-propyl amine, n-butyl amine ), dimethyl amine, dietyl amine, dipropyl amine, dibutyl amine, trimethyl amine, trietyl amine, tripropyl It may contain at least one selected from the group consisting of amine (tripropyl amine), tributyl amine (tributyl amine) and ammonium hydroxide (ammonium hydroxide). The basic catalyst can help to control the hydrolysis rate of each component during hydrolysis of two or three alkoxides or salts, thereby securing sphericity and uniformity of the particles. Preferably, the basic catalyst may use ammonia.

In one embodiment, the basic material may have a pH of 7 to 10. The addition amount of the basic material may be added until the pH of the mother liquor is usually around 9.

In one embodiment, in the step of preparing the basic material, the temperature of the basic material may be 60 ℃ to 85 ℃. The basic material is preferably pre-heated to 60 to 85 ° C where reflux is possible before proceeding to the next step, the dropping step.

In one embodiment, the silicon alkoxide is tetraethylorthosilicate (TEOS), 3-mercaptopropyltrimethoxysilane (MPTMS), phenyltrimethoxysilane (PTMS), vinyltrimethoxysilane (VTMS) , Methyltrimethoxysilane (MTMS), 3-aminopropyltrimethoxysilane (APTMS), 3-glycidyloxypropyltrimethoxysilane (GPTMS), (3-trimethoxysilyl)propylmethacrylate ( TMSPMA), 3-mercaptopropyltrimethoxysilane (MPTMS) and 3- (trimethoxysilyl) propyl isocyanate (TMSPI) may include at least one selected from the group consisting of. Depending on the structure and particle size of the silica particles, a mixing ratio of two or more types of silicon alkoxides to be used can be appropriately selected.

In the present invention, preferably, tetraethylorthosilicate (TEOS) may be used as the silicon alkoxide. Currently, ultra-high purity colloidal silica particles in the semiconductor market are exclusively sold by Japan's FUSO. Tetramethylorthosilicate (TMOS) is used as the main raw material. Tetramethylorthosilicate (TMOS) is limited in its use due to environmental contamination and problems that can lead to blindness or death when handled carelessly. However, when tetraethylorthosilicate (TEOS) is used, the alcohol-based compound generated in the synthesis process is ethanol, and its use is very easy due to its relatively low risk compared to methanol in terms of hazards and handling precautions. Conventional silicon alkoxide, in particular, colloidal silica patents made of TEOS are mostly methods for synthesizing particles of 150 nm or more, which have very low dispersion stability due to large particles of 150 nm or more during slurry preparation, resulting in scratches in the semiconductor polishing process It is not appropriate to use it because it is the main factor that causes

Ultra-high purity colloidal silica particles according to an embodiment of the present invention are silica fine particles dispersed in a colloidal state in a medium such as water or alcohol, and can be used as an abrasive and improving physical properties in semiconductors and industries. When colloidal silica is used as an abrasive, it is essential to prepare particles of silica having a dense structure. It is desired to make particles with more fully formed siloxane bonds, and it is preferable to make particles with fewer remaining silanol groups.

In addition, the present invention does not use an additional alcohol solvent for tetraethylorthosilicate (TEOS), and grows by gradually adding commercially available tetraethylorthosilicate (TEOS) as a raw material to a base composed of water and a basic catalyst by dropping. Colloidal silica in the range of 10 nm to 100 nm is easily prepared by controlling the rate and size of particle growth step by step, and the content of silanol groups is reduced by applying a higher reaction temperature compared to the reaction temperature in conventional silica particle production. It can be sufficiently reduced to provide more dense silica particles.

In one embodiment, the reaction solution preparation step 120 is a step of preparing a reaction solution by dropping silicon alkoxide into the basic material.

In one embodiment, the step of preparing a reaction solution by dropping silicon alkoxide into the basic material may be adjusting the temperature of the reaction solution to 60 °C to 85 °C. When the temperature of the reaction solution reacts at a temperature of less than 60 ° C., particle bonding is affected, and generation of new particles proceeds faster than particle growth, and small particles of less than 10 nm are generated, affecting the association ratio (A.G). When reacting at a temperature higher than 85 ° C., the basic catalyst in the solution and the alcohol compound, which is an intermediate reactant, are vaporized and the reaction conditions are rapidly changed to generate non-uniform particles, which affects the final particle association ratio.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide on the basic material, when the basic material includes a basic catalyst and water, the dropping rate of the silicon alkoxide is 0.333 ml/min to 3.333 ml/min. min, and the dropping time may be 4 to 12 hours. In the case of the drop rate, although there is some variation in the particle properties, it is within the error range, and when checking the association ratio, it is not greatly affected because it has an association ratio suitable for viewing as a spherical monodispersity. When dropping at a rate of less than 0.333 ml/min, the conditions for particle reaction become unstable due to an increase in base concentration due to base evaporation by temperature, and when dropping at a rate of more than 3.333 ml/min, the reaction time also increases. This is due to the increase in production cost.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide to the basic material, when the basic material includes basic catalyst seed particles and water, the dropping rate of the silicon alkoxide is 0.3 ml/min to 4 ml/min, and the dropping time may be 4 to 12 hours. When dropping at a rate of less than 0.3 ml/min, there is a problem in that the particle generation conditions become unstable due to the increase in base concentration at a rate of 0.3 ml/min or less, and the hydrophobic nature of silicon alkoxide itself when dropping at a rate of more than 4 ml/min Due to this, layer separation occurs and affects the shape and density of the particles.

In one embodiment, in the step of preparing a reaction solution by dropping silicon alkoxide on the basic material, the basic catalyst may be 1% to 4% by weight based on the weight of the silicon alkoxide. In the case of the basic catalyst, the absolute value of the overall particle size increases when the absolute amount thereof increases, but when the amount is less than 1% by weight relative to the weight of silicon alkoxide, particle formation is unstable due to volatilization of the catalyst and synthesis takes a long time, resulting in unreacted reactants It remains, and if it is more than 4% by weight, inferring from the associative ratio, the growth of the particles may show poor density.

In one embodiment, the aging step 130 is a step of aging the reaction solution.

In one embodiment, the aging of the reaction solution (130) may be performed at a temperature of the reaction solution at 60 °C to 85 °C for 1 hour to 5 hours. The aging step proceeds immediately after the dropping process, and the reaction temperature proceeds the same as the dropping process. The aging time is preferably 1 hour or longer, more preferably 3 hours or longer. During aging, unreacted silicon alkoxide may remain depending on the amount of dripping when the aging is performed for less than 1 hour, and then a precipitate may be generated due to the combination of the particles and the unreacted silicon alkoxide, which may affect the stability of the particles.

In one embodiment, the heating step 140 is a step of heating the reaction solution in a state in which the aging is completed.

In one embodiment, the step of heating the aged reaction solution may be to heat the temperature of the reaction solution to 99 ℃.

In one embodiment, the concentrating step (150) is a step of concentrating the heated reaction solution using a vacuum concentrator.

In one embodiment, the step of concentrating the heated reaction solution using a vacuum concentrator may include adding distilled water three times or more of the heated reaction solution and concentrating the heated reaction solution to a silica concentration of 10% to 25% by weight. . During concentration by substitution, when concentrated by adding distilled water less than 3 times, the stability of the particles may decrease during long-term storage due to the influence of residual alcohol and basic catalyst.

The ultra-high purity colloidal silica particles according to an embodiment of the present invention thus prepared have an average particle diameter of 10 nm to 200 nm, and a particle center value of 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, It is preferable to have a spherical shape of 60 nm, 70 nm, 80 nm, 90 nm and 100 nm. Here, the spherical shape includes not only a perfect spherical shape but also a slightly elliptical spherical shape. Also, it means the surface area of a ball having the same volume as the actual particle/the actual particle surface area.

In one embodiment, the method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention may be manufactured using one or more build-up methods to increase the size of the ultra-high purity silica particles step by step. may be

The method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention is a method in which silicon alkoxide is directly dropped onto a basic catalyst without the need for a separate alcohol addition and alcohol recollecting device, and is dense and stable with a size of 10 nm to 100 nm. These excellent high-purity colloidal silica particles can be produced.

Ultra-high purity colloidal silica particles according to another embodiment of the present invention are prepared by a method for producing ultra-high purity colloidal silica particles according to an embodiment of the present invention.

In one embodiment, the ultra-high purity colloidal silica particles may have a particle diameter of 10 nm to 100 nm.

Ultra-high purity colloidal silica particles according to an embodiment of the present invention have a monodisperse spherical shape having substantially the same size, and these monodisperse spherical particles can be provided as a raw material for the production of high purity SiC.

In one embodiment, the ultra-high purity colloidal silica particles may have a contact angle with respect to water of 100 ° to 170 °. When the contact angle of the ultra-high purity colloidal silica particles with water is less than 100 °, the hydrophobicity is low, and there is a problem of moisture adsorption or aggregation in the air. Since it is difficult to expect an improved effect, it is good to carry out within the above range.

In one embodiment, the ultra-high purity colloidal silica particles may satisfy Equation 1 below.

[Equation 1]

D ₁ /D ₂ ≤ 1.6

(D ₁ is the particle size value measured using DLS equipment, D ₂ is the value obtained by converting the specific surface area measured using BET equipment into particle size).

In one embodiment, when the D ₁ /D ₂ value of the ultra-high purity colloidal silica particles is 1.6 or less, the colloidal silica may have a monodisperse particle shape.

Ultra-high-purity colloidal silica particles according to an embodiment of the present invention are composed of an aqueous dispersion of ultra-high-purity silica and contain a very small amount of metal ions and organic base compounds.

Hereinafter, the present invention will be described in detail with reference to the following Examples and Comparative Examples. However, the technical spirit of the present invention is not limited or limited thereby.

[Example 1]

(1) Manufacture of basic materials (Base)

A base was prepared by adding 5 g of ammonia water (28 wt%) as a basic catalyst to 800 g of distilled water in a 2 L four-necked flask.

Before entering the dropping process, the liquid temperature was raised and maintained at 80 ° C through sufficient preheating.

(2) loading

200 g of TEOS was prepared by subdividing into a 250 ml beaker.

A viton tube from Master Flex was used as the fitting tube, and a rubber stopper was used to prevent evaporation of the basic catalyst in the flask.

The dropping pump was added at a rate of 0.333 ml/min using a metering pump.

The total loading time was 4 hours and 30 minutes.

(3) Aging

After dripping, the aging process was performed for 3 hours while maintaining the liquid temperature of 80 ℃.

(4) Concentration and pure substitution

Ammonia and ethanol were removed by heating the reaction liquid after the aging process until the liquid temperature reached 100 °C. Thereafter, distilled water was added in an amount three times the weight of the solution, and concentrated using a vacuum concentrator until the silica concentration reached 20% by weight to prepare ultra-high purity colloidal silica particles.

[Example 2]

Ultra-high purity colloidal silica particles were prepared in the same manner as in Example 1, except that in the dropping process of Example 1, the dropping speed was the same for 9 hours.

[Example 3]

Except for using a 3% by weight aqueous solution of the particles of Example 1 instead of 800 g of distilled water in the base material manufacturing process of Example 1, ultra-high purity colloidal silica particles were prepared in the same manner as in Example 1.

[Example 4]

Except for using a 3% by weight aqueous solution of the particles of Example 2 instead of 800 g of distilled water in the basic material (Base) manufacturing process of Example 1, ultra-high purity colloidal silica particles were prepared in the same manner as in Example 1.

[Example 5]

Except for using a 3% by weight aqueous solution of the particles of Example 3 instead of 800 g of distilled water in the base material manufacturing process of Example 1, ultra-high purity colloidal silica particles were prepared in the same manner as in Example 1.

[Example 6]

Except for using a 3% by weight aqueous solution of the particles of Example 4 instead of 800 g of distilled water in the basic material (Base) manufacturing process of Example 1, the rest of the process was the same as in Example 1 to prepare ultra-high purity colloidal silica particles.

Table 1 below shows the physical properties of colloidal silica particles according to Examples 1 to 6 of the present invention.

unit Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 physical Particle
Size
(PSA) nm 21.4 35.4 38.2 76.2 55.8 96.4 Surface
Area
(BET) m ² /g
(nm) 17 27.1 30.7 59.1 46.1 71.4 A.R. - 1.26 1.31 1.25 1.29 1.21 1.35 total
solid wt% 20 20 20 20 20 20 pH - 7.25 7.18 7.25 7.18 7.24 7.32 Specific
Gravity - 1.120 1.120 1.120 1.120 1.120 1.120 viscosity CPS 7.2 7.6 7.2 7.6 8.2 8.2 metal
ion Al ppm 0.051 0.129 0.051 0.129 0.022 0.048 Fe ppm 0.837 0.45 0.837 0.45 0.194 0.204 Ni ppm 0.001 0.000 0.001 0.000 0.001 0.00 Cu ppm 0.005 0.003 0.005 0.003 0.014 0.005 NH4 ppm less than 50 less than 50 less than 50 less than 50 less than 50 less than 50 alcohol % N.D. N.D. N.D. N.D. N.D. N.D.

Referring to Table 1, the ultra-high purity colloidal silica abrasive particles according to Examples 1 to 6 of the present invention are relatively reactive compared to TMOS only by adjusting the parameters that affect hydrolysis and siloxane bonding during particle generation. Even using a low TEOS, particles with a size of less than 100 nm could be prepared. In addition, it was confirmed that the particle size of the desired size can be adjusted by changing various conditions.

When preparing basic materials, it was possible to increase the size of ultra-high purity silica particles step by step using a build-up method by including already prepared colloidal silica particles as seed particles instead of distilled water.

2 to 7 are TEM images of colloidal silica particles according to Examples 1 to 7 of the present invention. As shown in FIGS. 2 to 7 , it was confirmed that sufficiently dense particles having a size of 100 nm or less could be produced.

As a result of analyzing the ultra-high purity colloidal silica abrasive particles according to Examples 1 to 6 of the present invention by ICP-MS, it was confirmed that the total metal content was 10 ppm or less and the ammonia residual amount was 50 ppm or less.

As described above, although the embodiments have been described with limited drawings, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques may be performed in an order different from the method described, and/or components of the described system, structure, device, circuit, etc. may be combined or combined in a different form than the method described, or other components may be used. Or even if it is replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents of the claims are within the scope of the following claims.

Claims (18)

preparing a basic material;
preparing a reaction solution by dropping silicon alkoxide into the basic material;
aging the reaction solution;
heating the aged reaction solution; and
Concentrating the heated reaction solution using a vacuum concentrator;
including,
The step of preparing the basic material,
one containing a basic catalyst and water;
comprising basic catalyst seed particles and water;
In the step of preparing a reaction solution by dropping silicon alkoxide into the basic material, when the basic material includes a basic catalyst and water, the dropping rate of the silicon alkoxide is 0.333 ml/min to 3.333 ml/min, and the dropping time is 4 hours to 12 hours,
In the step of preparing a reaction solution by dropping silicon alkoxide into the basic material, when the basic material includes basic catalyst seed particles and water, the dropping rate of the silicon alkoxide is 0.3 ml/min to 4 ml/min, and the dropping rate is 0.3 ml/min to 4 ml/min. The time is from 4 hours to 12 hours,
In the step of preparing a reaction solution by dropping silicon alkoxide into the basic material, the basic catalyst is 1% to 4% by weight based on the weight of the silicon alkoxide,
In the step of aging the reaction solution, the temperature of the reaction solution is carried out at 60 ℃ to 85 ℃ for 1 hour to 5 hours,
The reaction solution is added dropwise as a raw material without using any alcohol other than silicon alkoxide,
The basic catalyst seed particles are 1% to 5% by weight of the basic material, and the particle size of the seed particles is 40 nm or less,
The silicon alkoxide is 3-mercaptopropyltrimethoxysilane (MPTMS), phenyltrimethoxysilane (PTMS), vinyltrimethoxysilane (VTMS), methyltrimethoxysilane (MTMS), 3-aminopropyltri Methoxysilane (APTMS), 3-glycidyloxypropyltrimethoxysilane (GPTMS), (3-trimethoxysilyl)propylmethacrylate (TMSPMA), 3-mercaptopropyltrimethoxysilane (MPTMS) And 3- (trimethoxysilyl) propyl isocyanate (TMSPI) containing at least one selected from the group consisting of,
In the step of concentrating the heated reaction solution using a vacuum concentrator, distilled water three times or more of the heated reaction solution is added and concentrated to a silica concentration of 10% to 25% by weight,
Method for producing ultra-high purity colloidal silica particles.
delete delete According to claim 1,
The basic catalyst,
Ammonia, methyl amine, ethyl amine, n-propyl amine, n-butyl amine, dimethyl amine, diethyl Dietyl amine, dipropyl amine, dibutyl amine, trimethyl amine, trietyl amine, tripropyl amine, tributyl amine amine) and at least one selected from the group consisting of ammonium hydroxide,
Method for producing ultra-high purity colloidal silica particles.
According to claim 1,
The basic material has a pH of 7 to 10,
Method for producing ultra-high purity colloidal silica particles.
According to claim 1,
In the step of preparing the basic material,
The temperature of the basic material is 60 ℃ to 85 ℃,
Method for producing ultra-high purity colloidal silica particles.
delete According to claim 1,
The step of preparing a reaction solution by dropping silicon alkoxide into the basic material,
The temperature of the reaction solution is adjusted to 60 ℃ to 85 ℃,
Method for producing ultra-high purity colloidal silica particles.
delete delete delete delete According to claim 1,
The step of heating the aged reaction solution,
Heating the reaction solution until it reaches 99 ° C.
Method for producing ultra-high purity colloidal silica particles.
delete Ultra-high-purity colloidal silica particles prepared by the method for producing ultra-high-purity colloidal silica particles of claim 1.
According to claim 15,
The ultra-high purity colloidal silica particles have a particle diameter of 10 nm to 100 nm,
Ultra-high purity colloidal silica particles.
According to claim 15,
The ultra-high purity colloidal silica particles have a contact angle to water of 100 ° to 170 °,
Ultra-high purity colloidal silica particles.
According to claim 15,
The ultra-high purity colloidal silica particles satisfy Equation 1 below,
Ultra high purity colloidal silica particles:
[Equation 1]
D ₁ /D ₂ ≤ 1.6
(D ₁ is the particle size value measured using DLS equipment, D ₂ is the value obtained by converting the specific surface area measured using BET equipment into particle size).

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