JP6385639B2 - Method for producing polishing composition - Google Patents

Description

  The present invention relates to a method for producing a polishing composition.

  The polishing composition is produced, for example, by mixing abrasive grains, a basic compound, an organic compound, and water. The obtained polishing composition is used for polishing using, for example, a silicon substrate as an object to be polished. Coarse particles contained in the polishing composition can be reduced by a filtration process (see, for example, Patent Document 1).

JP 2006-136996 A

  In the raw material mixing step of mixing the raw material of the polishing composition, a production facility including a pipe for transporting the liquid raw material is used. If the gas phase is present in the pipe and the raw material is kept attached to the inner wall of the pipe, the raw material is likely to adhere to the inner wall, and such raw material is dispersed or dissolved even if it is brought into contact with water or an aqueous solution again. It becomes difficult. As a result, raw materials that are insufficiently dispersed or dissolved may be mixed as coarse particles in the polishing composition, which may deteriorate the quality of the product.

  Although coarse particles can be reduced, for example, by the filtration step described in Patent Document 1, the particles cannot be completely removed even after the filtration step, and are essentially coarse. It is preferable to suppress the generation of the particles themselves.

  This invention is made | formed in view of such a situation, The objective is to provide the manufacturing method of the polishing composition which can suppress mixing of a coarse particle easily.

A method for producing a polishing composition that solves the above problems includes a sending side container, a receiving side container, and a pipe that transports a liquid raw material containing at least a water-soluble polymer from the sending side container to the receiving side container. A manufacturing method of a polishing composition having a raw material mixing step of mixing raw materials containing abrasive grains, a water-soluble polymer, and a basic compound using a manufacturing facility provided, wherein the pipe is transported after cleaning water, or an aqueous solution containing no water-soluble polymer and abrasive grains filled to the start of, after the raw material mixing step, the filling step of the polishing composition is performed.

In the said manufacturing method of polishing composition, it is preferable to use the aqueous solution containing at least 1 type of a basic compound, an oxidizing agent, and a fungicide as said aqueous solution.
In the method for producing a polishing composition, it is preferable that the feeding container contains at least a water-soluble polymer, a basic compound, and water, and the receiving container contains at least abrasive grains and water.

  According to the present invention, it becomes easy to suppress the mixing of coarse particles.

Hereinafter, an embodiment of the present invention will be described.
The manufacturing method of polishing composition has a raw material mixing process which mixes a raw material. In the raw material mixing step, a production facility including a sending side container, a receiving side container, and a pipe for transporting a liquid raw material from the sending side container to the receiving side container is used.

  As an example, there may be mentioned one in which an inflow and an outflow on-off valve are provided at the ends of the sending side and receiving side containers in the pipe, respectively. The piping between the outflow side on-off valve and the main mixing container is constituted by a T-shaped tube having a switching valve. A pump for receiving the raw material in the feed side container and transporting it into the side container is provided on the pipe downstream of the inflow side on / off valve and upstream of the outflow side on / off valve.

  It is preferable that the inner peripheral surface of the flow path constituted by piping or the like is formed from a non-metallic material. Examples of non-metallic materials include resin materials and ceramics. Examples of the resin material include olefin resin, vinyl chloride resin, fluorine resin, acrylic resin, acrylonitrile-butadiene-styrene copolymer resin (ABS resin), and polyisobutylene resin.

  Examples of the olefin resin include a polypropylene resin and a polyethylene resin. Examples of the vinyl chloride resin include polyvinyl chloride resins and polyvinylidene chloride resins. Examples of the fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / ethylene copolymer (ETFE), and tetrafluoroethylene / hexafluoropropylene. Copolymer (FEP), polyvinylidene fluoride (PVDF), and ethylene-chlorotrifluoroethylene copolymer (ECTFE). An example of the ceramic is hexagonal boron nitride.

Among non-metallic materials, a fluororesin is preferable from the viewpoint of excellent corrosion resistance.
The feeding side container includes a container for storing the raw material and a stirrer or a disperser. Examples of the stirrer or disperser include a wing stirrer, an ultrasonic disperser, and a homomixer. The receiving side container also includes a container for storing the raw material and a stirrer or a disperser.

  The pipe is filled with water or an aqueous solution until the start of transportation of the raw material. In order to fill the pipe with water or an aqueous solution, for example, the inflow side on-off valve and the outflow side on-off valve are opened, and the pump is operated. Thereby, water or aqueous solution is supplied to piping from a sending side container. Next, the inflow side on-off valve and the outflow side on-off valve are closed, and the pump is stopped. Thereby, the whole flow path located between the inflow side on-off valve and the outflow side on-off valve is filled with water or an aqueous solution.

  When a pipe is filled with water or an aqueous solution, in the batch production process, the raw material mixing process of the immediately preceding production (hereinafter referred to as “immediate lot”) is completed, and the flow path composed of the pipe and the like is washed. Is preferred. It is preferable that the cleaned pipe is filled with water or an aqueous solution before being dried. A lot represents a product unit generated in a business such as manufacturing.

  The water or aqueous solution is preferably filled so as to be 50% by volume or more, more preferably 60% by volume or more, and further preferably 70% by volume or more when the capacity of the entire flow path of the pipe is 100. It is.

  For example, the water preferably has a total content of transition metal ions of 100 ppb or less. For example, the purity of water can be increased by operations such as removal of impurity ions using an ion exchange resin, removal of foreign matters by a filter, and distillation. Specifically, for example, ion exchange water, pure water, ultrapure water, or distilled water is preferably used, and ultrapure water is more preferably used.

Examples of the water-soluble component in the aqueous solution include basic compounds, oxidizing agents, fungicides, chelating agents, and surfactants.
Examples of the basic compound include an alkali metal hydroxide, quaternary ammonium hydroxide or a salt thereof, ammonia, and an amine. Examples of the alkali metal hydroxide include potassium hydroxide and sodium hydroxide. Examples of the quaternary ammonium hydroxide or a salt thereof include tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide. Examples of amines include methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, monoethanolamine, N- (β-aminoethyl) ethanolamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, anhydrous piperazine, Examples include piperazine hexahydrate, 1- (2-aminoethyl) piperazine, N-methylpiperazine, and guanidine.

Examples of the oxidizing agent include hydrogen peroxide, peracetic acid, percarbonate, urea peroxide, perchloric acid, perchlorate, persulfate, periodate, and permanganate.
Examples of fungicides include phenolic compounds, iodine compounds, thiazoline compounds, isothiazoline compounds, quaternary ammonium salt compounds, and organic amine compounds.

Examples of chelating agents include aminocarboxylic acid chelating agents and organic phosphonic acid chelating agents.
Examples of the surfactant include nonionic, anionic, cationic or amphoteric surfactants.

The aqueous solution preferably contains at least one of a basic compound, an oxidizing agent, and a fungicide.
The content of the water-soluble component in the aqueous solution is preferably in the range of 0.0001% by mass or more and 10% by mass or less, for example.

  In the raw material mixing step, the liquid raw material is transported from the sending container to the receiving container. The water or aqueous solution filled in the pipe is pushed out of the pipe by supplying a liquid raw material to the pipe. The water or the aqueous solution filled in the pipe may be supplied to the receiving container together with the liquid raw material, or may be discharged out of the production facility. When water or an aqueous solution is supplied to the receiving container together with the liquid raw material, the concentration of the liquid raw material in the sending container or the inside of the receiving container is assumed assuming that the raw material is mixed with water or an aqueous solution. It is preferable to adjust the concentration of the liquid raw material. In addition, when discharging water or aqueous solution out of a manufacturing facility, said switching valve can be utilized, for example.

  As a liquid raw material accommodated in a sending side container, the mixture of an abrasive grain, a water-soluble polymer, a basic compound, and water is mentioned, for example. As a liquid raw material accommodated in a receiving side container, the mixture of an abrasive grain, a basic compound, and water is mentioned, for example.

  Examples of the abrasive material include silicon oxide, aluminum oxide, zirconium oxide, cerium oxide, and titanium oxide. An abrasive grain may be used individually by 1 type, and may be used in combination of 2 or more type.

  As the water-soluble polymer, those having at least one functional group (hydrophilic group) selected from a cationic group, an anionic group and a nonionic group in the molecule can be used. Examples of the water-soluble polymer include those containing a hydroxyl group, a carboxyl group, an acyloxy group, a sulfo group, a quaternary nitrogen structure, a heterocyclic structure, a vinyl structure, and a polyoxyalkylene structure in the molecule.

  Examples of the water-soluble polymer include cellulose derivatives, imine derivatives such as poly (N-acylalkyleneimine), polyvinyl alcohol, polyvinyl pyrrolidone, copolymers containing polyvinyl pyrrolidone as part of the structure, polyvinyl caprolactam, and polyvinyl caprolactam. A copolymer having a part of the structure, a polyoxyethylene, a polymer having a polyoxyalkylene structure, a copolymer having a plurality of types such as a diblock type, a triblock type, a random type, and an alternating type; and Examples include polyether-modified silicone. Examples of the cellulose derivative include hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose, methyl cellulose, ethyl cellulose, ethyl hydroxyethyl cellulose, and carboxymethyl cellulose. A water-soluble polymer may be used individually by 1 type, and may be used in combination of 2 or more type.

As the water and the basic compound, those described as the basic compound contained in the water or the aqueous solution filled in the pipe are used.
In the manufacturing method of polishing composition, a filtration process and a filling process are implemented after the said raw material mixing process, for example.

  The polishing composition obtained through the raw material mixing step is used for polishing using, for example, a silicon substrate, a metal such as stainless steel, a silicon oxide substrate, a plastic substrate, a glass substrate, and a quartz substrate.

Next, the effect | action of the manufacturing method of polishing composition is demonstrated.
In the raw material mixing step, a manufacturing facility having piping is used. The piping transports the liquid raw material from the sending container to the receiving container. The pipe is filled with water or an aqueous solution until the start of transportation. Thereby, since the drying of the flow path which piping has is suppressed, it is estimated that it is suppressed that the substance which becomes a cause of a coarse particle adheres to the internal peripheral surface of a flow path.

According to the embodiment described in detail above, the following effects are exhibited.
(1) In the raw material mixing step, a production facility including a sending side container, a receiving side container, and a pipe for transporting a liquid raw material from the sending side container to the receiving side container is used. The pipe is filled with water or an aqueous solution until the start of transportation of the raw material. According to this method for producing a polishing composition, it becomes easy to suppress the incorporation of coarse particles.

  (2) It is preferable to use an aqueous solution containing at least one of a basic compound, an oxidizing agent and an antifungal agent as the aqueous solution filled in the pipe. In this case, it becomes easier to suppress the mixing of coarse particles.

(Example of change)
The embodiment may be modified as follows.
-Although the manufacturing equipment of the above-mentioned embodiment has one sending side container, it may be changed into the manufacturing equipment provided with a plurality of sending side containers. In this case, the liquid raw material is transported from each sending side container to a receiving side container through a separate pipe. In this modified example, it is sufficient that at least one of the plurality of pipes is filled with water or an aqueous solution until the start of transportation. In addition, the receiving-side container of this modified example may be used as a container for mixing raw materials transported from the respective feeding-side containers, in which the raw materials are not stored in advance and are empty.

-Another raw material mixing process may be included as a pre-process or a post-process of the raw material mixing process of the embodiment.
-At least one of the sending side container and the receiving side container may be filled with water or an aqueous solution until the start of transportation in the same manner as the pipe. In this case, the water or the aqueous solution may be filled in a part of the sending side container and the receiving side container, or may be filled as a whole.

Next, the embodiment will be specifically described with reference to examples and comparative examples.
Example 1
After the raw material used as the previous lot was discharged from the piping, the sending side container, the receiving side container and the piping were washed with water. In the previous lot, a mixture of hydroxyethyl cellulose, ammonia, and water was transported from the sending container to the receiving container as a liquid raw material. Next, water was filled in the flow path between the inflow-side on-off valve and the outflow-side on-off valve in the pipe immediately after cleaning, and left in that state for 24 hours.

  In the production after leaving for 24 hours (hereinafter referred to as “this lot”), a feeding-side container contains a mixture of hydroxyethylcellulose, ammonia, and water, and a receiving-side container contains colloidal silica, ammonia, and water. The mixture was accommodated. Next, the water filled in the piping was discharged out of the production facility, and the mixture in the sending side container was transported to the receiving side container. Subsequently, a composition was obtained by mixing the transported mixture with the mixture in the receiving container. The number of coarse particles of 0.56 μm or more contained in the obtained composition was measured by a particle size distribution analyzer (trade name: Accusizer MODEL 780, manufactured by Particle Sizing Systems). As a result, it was about 3000 particles / mL. It was.

(Example 2)
In Example 2, a composition was prepared in the same manner as in Example 1 except that a pipe filled with ammonia water having a pH of 10.0 was used. As a result of measuring the number of coarse particles of 0.56 μm or more contained in the obtained composition with the particle size distribution analyzer, it was about 2000 particles / mL.

(Example 3)
In Example 3, a composition was prepared in the same manner as in Example 1 except that a pipe filled with 1% by mass of hydrogen peroxide was used. The number of coarse particles of 0.56 μm or more contained in the obtained composition was measured by the particle size distribution measuring instrument, and found to be about 1800 particles / mL.

Example 4
In Example 4, a composition was prepared in the same manner as in Example 1 except that a pipe filled with 1% by mass of a fungicide aqueous solution (trade name: Biovan CS-1135, manufactured by Riken Green Co., Ltd.) was used. . The number of coarse particles of 0.56 μm or more contained in the obtained composition was measured by the particle size distribution measuring instrument, and found to be about 1800 particles / mL.

(Example 5)
In Example 5, a composition was prepared in the same manner as in Example 1 except that the amount of water filled in the piping was changed to about 50% of the volume of the flow path. As a result of measuring the number of coarse particles of 0.56 μm or more contained in the obtained composition with the particle size distribution analyzer, it was about 25000 particles / mL.

(Comparative Example 1)
In Comparative Example 1, a composition was prepared in the same manner as in Example 1 except that the raw material mixing step of the current lot was performed without filling the pipe with water. The number of coarse particles of 0.56 μm or more contained in the obtained composition was measured by the particle size distribution measuring instrument, and found to be about 80000 particles / mL.

Claims (3)

Abrasive grains, water-soluble polymer using a production facility comprising a feeding-side container, a receiving-side container, and a pipe for transporting a liquid raw material containing at least a water-soluble polymer from the sending-side container to the receiving-side container, And the manufacturing method of the polishing composition which has the raw material mixing process of mixing the raw material containing a basic compound,
The pipe, after washing, the until the start of transport of water, or an aqueous solution containing no water-soluble polymer and abrasive grains is filled, after the raw material mixing step, the filling process of the polishing composition is carried A method for producing a polishing composition comprising:   The manufacturing method of the polishing composition of Claim 1 using the aqueous solution containing at least 1 type of a basic compound, an oxidizing agent, and a fungicide as said aqueous solution. The sending side container contains at least a water-soluble polymer, a basic compound and water,
The method for producing a polishing composition according to claim 1, wherein the receiving container contains at least abrasive grains and water.