KR100483185B1 - Equipment for manufacturing globe-shaped silica particle powder - Google Patents

Abstract

The present invention relates to a spherical particulate powder production apparatus for producing silica powder for use as a filler for silicon wafer abrasives and epoxy fillers for integrated circuit package production into spherical, uniformly distributed particles.

In order to produce spherical silica powder, a silica sol is dropletized by an ultrasonic generator using the apparatus for preparing particulate powder according to the present invention, and transferred into a tube of a reactor to dry them in a reactor at a constant temperature.

By this method it is possible to mass produce silica powder with a uniform distribution of less than a few microns.

Description

Spherical Silica Powder Manufacturing Equipment {EQUIPMENT FOR MANUFACTURING GLOBE-SHAPED SILICA PARTICLE POWDER}

FIELD OF THE INVENTION The present invention relates to a spherical particulate powder manufacturing apparatus, wherein a spherical silica powder for producing a silicon wafer abrasive and a silica powder for use as a filler for an epoxy filler for integrated circuit package production into spherical and uniformly distributed particles. It relates to a manufacturing apparatus.

In general, silica powder is used in various fields such as silicon wafer abrasives, fillers for strengthening the hardness. In particular, the rapid growth of high-integration technology requires high-efficiency microparticles suitable for their application, and researches on the generation technology of spherical submicron level particles are being conducted.

There are several techniques for producing such spherical particles. Among them, the coprecipitation method or the sol-gel method, which is a kind of liquid phase method, has a disadvantage in that the process is very complicated and the size distribution of the prepared fine powder is constant, but the size is not easy to control. In addition, it is known that the actual production required by the industry is very difficult. That is, they are not suitable for the production of high demands and are not efficient for producing particles larger than micrometers (µm). In addition, the most widely used method for producing a particle is a method of manufacturing each raw material by firing at high thermal energy. At present, these particles are used as low-grade particles because they are poor in particle size and particle formation.

Silica (SiO ₂ ) is widely used industrially because of its excellent resistance to external changes, mechanical shock, and thermal expansion. Due to these properties, silica powder having a particle size of less than micrometer and having a large surface area is known to have excellent properties as a filler.

The properties of the fillers of epoxy fillers for the manufacture of integrated circuit packages must be able to increase their strength while minimizing thermal expansion. It is also desirable that the content of ions be low and that they have a relatively high thermal conductivity. Currently, about 80% or more of the total amount of the filler is made of silica powder. To satisfy these characteristics, it is very important to control the particle size, distribution, and shape of the silica powder. These characteristics play an important role in enabling high integration, miniaturization and thinning of the semiconductor, and it is particularly important to maintain the spherical shape not only to secure the fluidity but also to maximize the packing density during the encapsulation process. Various methods have been studied for the preparation of silica, and the range of application of the prepared silica is also different. Recently, there is a need to synthesize spherical silica at a lower cost, which can increase the larger surface area and packing density.

In addition, with high integration of semiconductor devices, the wiring technology is further miniaturized and moving in the direction of multilayering. As the level between the layers increases as the wiring becomes smaller and progresses, the processing accuracy and reliability of the wiring formed thereon tend to be lowered. In order to solve the above problems, a chemical mechanical polishing (hereinafter, referred to as CMP polishing) method is attracting attention, and silica is attracting attention as a raw material of the abrasive used in such CMP polishing. By the way, the abrasive used in the conventionally used fume silica for the abrasive particles is excellent in purity, but there was a problem such as a lot of scratches, if the spherical silica fine and even particle size can solve the above problems. Therefore, there is a demand for a method for mass production of such silica powder.

An object of the present invention for solving such a problem is to optimize the manufacturing process by controlling the suitably dissolved raw material salt and by using the droplet generator and drying apparatus of ultrasonic spraying, the filler of the epoxy filler for the integrated circuit package or silicon wafer abrasive It is an object of the present invention to provide a spherical silica production method and apparatus for synthesizing a large amount of silica (SiO ₂ ) suitable for use as a spherical silica powder of several micrometers or less.

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The spherical particulate powder manufacturing apparatus according to the present invention for solving the above object is an ultrasonic generator for forming a silica sol containing colloidal silica as a main material as droplets of a predetermined size using ultrasonic waves, and installed on one side of the ultrasonic generator to increase the airflow A heating element for generating the droplets to be introduced into the vertical reactor through the tube, and a vertical reactor for heating the droplets supplied through the tube to a constant temperature to form spherical silica powder, in which particles are collected. It comprises a collector equipped with a filter cloth and an inhaler installed around the collector so that the silica powder passing through the reactor is collected in the collector, the internal temperature of the reactor is preferably 100 ℃ to 300 ℃. If the temperature of the reactor is less than 100 ° C., the moisture in the droplets is not completely dried. Therefore, agglomeration occurs when the silica powder is collected, and if the temperature of the reactor exceeds 300 ° C., the average particle diameter is several. It is rapidly larger than the micrometer, the particle size distribution is widened, and agglomerated particles are obtained.

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In addition, the apparatus may further include a cooling unit installed around the reactor to condense moisture in the droplets that were vaporized in the reactor.

In addition, the tube of the device may be formed so that the droplets from the ultrasonic generator is rotated 180 ° to be introduced into the reactor.

EMBODIMENT OF THE INVENTION Hereinafter, the spherical fine particle powder manufacturing method and apparatus which concern on this invention are demonstrated in detail with reference to drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing an example in an apparatus for producing spherical particulate powder by ultrasonic waves used in the present invention.

In the spherical particulate powder manufacturing apparatus according to the present invention, in order to transfer the droplets generated in the ultrasonic generator 12 and the ultrasonic generator 12 to form a silica sol into droplets of a predetermined size using ultrasonic waves to a reactor through a tube. The tube 18 and the tube for connecting the heating element 16, the ultrasonic generator 12, and the reactor 20 installed around the ultrasonic generator to connect the droplets generated by the ultrasonic generator 12 to the reactor 20. 18 is a reactor (20) for heating the droplets supplied through a constant temperature to form a spherical silica powder, the collector 26 so that the silica powder passed through the reactor 20 can be collected by the collector 26 well. Inhaler 30 connected to the), and comprises a flask 32 installed directly below the tube 18 in the center of the reactor 20 so that the moisture in the droplets that were vaporized in the reactor 20 condensed after .

The ultrasonic nebulizer 12 is a device that separates the solution into fine droplets due to capillary waves generated on the surface of the solution when the ultrasonic waves generated from the ceramic vibrator are concentrated on the surface of the solution. In the present invention, a domestic ultrasonic humidifier (output 42W) was used, and droplets were generated at an ultrasonic output characteristic of 1.67 MHz.

DuPont colloidal silica SYTON HT50F was used as the starting material. 100 g of this colloidal silica was added to 100 g of distilled water and stirred for 1 hour or more to prepare a colloidal sol. The colloidal sol prepared as described above was put in an ultrasonic atomizer to prepare droplets using an ultrasonic vibrator.

As shown in FIG. 1, a heating element 16 is installed on the side of the ultrasonic generator 12 to facilitate the transfer of the droplets sprayed through the nozzle to the reaction furnace 20.

The tube 18 is connected to the ultrasonic generator 12 and extends through the reactor 20 to the cooling unit 22, and droplets generated through the ultrasonic generator 12 are reacted through the tube 18. Up to 20). Tubes 18, such as in the spherical silica manufacturing apparatus as shown in FIG. 1, are made so that droplets from the ultrasonic generator 1 can be turned 180 ° into the reactor 16. In the present embodiment, the tube is made of plastic, which is easily bent, for the portion where the droplet enters by 180 °, and the portion made of the straight line is made of quartz.

As in the present embodiment, the droplets from the ultrasonic generator 12 are rotated 180 degrees to enter the quartz tube of the reactor 20. The heavy droplets (i.e., in the case of a powder later) among the droplets produced by the ultrasonic generator 12 are large. This is because the particle size distribution of the powder obtained can be uniform because particles hardly enter the tube.

As described above, the droplets rotated by 180 ° are passed through the quartz tube in which the reactor 20 is installed around the reactor. Thus, the reactor 20 is installed vertically. In this embodiment, an electric furnace was used as the reactor 20. The vertical electric furnace used in this embodiment has a thermocouple located in the center and maintains a constant temperature in the center of the reactor using a controller. In addition, since the temperature gradually decreases toward the lower portion of the thermocouple due to the characteristics of the vertical furnace, the temperature of the reactor refers to the temperature at which the thermocouple is located, that is, the central portion of the reactor.

Cooling unit 22 may be installed at the lower end of the reactor 20, for example, the cooling unit 22 may be installed in such a way that the cooling water supplied flows out to surround the quartz tube. This configuration allows for proper condensation of water in the quartz tube.

Collector 26 is a place to collect the silica powder 24, in detail, the vaporization of the droplets occurs as the heating is maintained at a constant temperature in the reactor 20, and thus the droplets in the form of a powder in the triangle It falls into the bottom through the funnel-shaped candle and captures this silica powder.

The aspirator 30 is installed in connection with the collector 26. Since the silica powder particles produced by the above process are very fine powders, free fall may not be easy, and thus the silica powder particles may be easily Is installed to do. A filter is installed between the inhaler 30 and the collector 26 to prevent silica powder from entering the inhaler 30.

The flask 32 is installed directly under the quartz tube in the center of the reactor 20 to collect moisture after condensation by cooling in the cooling unit 22 that has been vaporized in the reactor 20.

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Specific examples that can be obtained through such an apparatus will be described in detail with reference to FIG. 3 and below.

First, a silica sol was prepared using a starting material to prepare silica powder (S100). Dupont (colloidal silica) was used as a starting material. Table 1 below shows the characteristics of various colloidal silicas.

In addition, the pH of the colloidal silica measured by a pH meter (Hanna instruments model H18424 microcomputer pH meter) was 10.5, which was about the same as 10.2 found by DuPont. The particle size of the colloidal silica was analyzed using the LASER PARTICLE ANALYZER SYSTEM (OTSUKA Electronic Co., LTD model PAR-III), it can be seen that the average particle diameter of about 20nm.

Silica sol was prepared by adding 100 g of distilled water as a solvent to 100 g of colloidal silica as a starting material and stirring for 1 hour or more.

The colloidal silica sol thus prepared was placed in the ultrasonic generator 12 as shown in FIG. 1 and made into droplets using an ultrasonic vibrator (S120).

The droplets generated by the ultrasonic generator 12 are moved around the tube 18 by the hot air by the heating element 16 installed on the side of the ultrasonic generator, and moved to the reaction furnace. In the case of the silica powder manufacturing apparatus 10 by the vertical reactor as shown in FIG. 1, droplets from the ultrasonic generator 12 are rotated by 180 ° to enter the tube of the reactor.

In order to keep the internal temperature of the reactor constant, in this embodiment, as described above, an electric furnace was used as the reactor. As shown in FIG. 1, a vertical electric furnace has a thermocouple located at the center thereof, and maintains a constant temperature at the center of the electric furnace using a controller. In addition, due to the characteristics of the vertical furnace is gradually lowered toward the lower temperature, and therefore the internal temperature of the reactor refers to the temperature at which the central portion of the electric furnace, that is, the thermocouple is located.

The droplets passing through the reactor through the tube are dried by hot air, and the temperature inside the reactor has a very important influence on the formation of particles. In particular, the shape, the residue contained in the particles, and the size of the particles are affected by the temperature inside the reactor. In the present embodiment, first, the internal temperature of the electric furnace was kept constant at 100 ° C. to dry the silica powder, and then the internal temperature of the electric furnace was kept constant at 300 ° C. to dry the silica powder.

Silica particles produced after being completely dried in the reactor are passed out of the reactor, in the case of a vertical silica powder manufacturing apparatus such as shown in Figure 1 so that the powder falls to the bottom through the inside of the triangular funnel in the tube And gather in the collector. However, since the silica powders produced by drying are very fine, it is difficult to fall naturally, so that the pressure is lowered by connecting the inhaler to the outside of the collector so that the powder can be collected in the collector smoothly (S140).

As such, the collected silica powder was finally completed after drying (S150).

As for the powder thus obtained, its particle size distribution and the nougat fraction of the powder are shown in Figs.

First, FIG. 4A shows a particle size distribution when the internal temperature of the reactor is maintained at 100 ° C., and FIG. 4B shows a nominal fraction of powder particle diameter. The particle size of the obtained molecule showed a relatively even particle size distribution of 1 μm to 300 nm, and an average particle diameter of about 520 nm.

Next, FIG. 5A shows a particle size distribution when the internal temperature of the reactor is maintained at 300 ° C., and FIG. 5A shows a nominal fraction of powder particle diameter. The particle diameter of the powder obtained at this time was 2 micrometers-500 nm, and the average particle diameter was about 900 nm.

This invention can be implemented in other various forms, without deviating from the mind or main characteristics. Therefore, the above-described embodiments are merely examples in all respects and should not be interpreted limitedly. In addition, all the deformation | transformation and a change which belong to the equal range of a claim belong to the scope of the present invention.

According to the present invention, by optimizing the manufacturing process by using an ultrasonic spray device and a drying device, silica (SiO ₂ ) used in wafer abrasives, fillers for epoxy fillers for integrated circuit packages, etc. may be synthesized into spherical silica of several micrometers or less. There is an effect of improving the yield, it is easy to process, excellent in reproducibility, and the effect of being able to easily and in large quantities to produce a multi-component particles of complex components.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 schematically shows an example of a spherical particulate powder manufacturing apparatus having a vertical reactor by ultrasonic waves used in the present invention.

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3 is a flowchart showing an example of a method for producing spherical fine particles according to the present invention.

4A and 4B show particle size distributions of silica powders obtained when the internal temperature of the reactor is maintained at 100 ° C.

5A and 5B show particle size distributions of silica powders obtained when the internal temperature of the reactor is maintained at 300 ° C.

※ Explanation of code about main part of drawing ※

12: ultrasonic generator 16: heating element

18 tube 20 reactor

22: cooling part 24: silica powder

26: Collector 28: Filter

30: inhaler 32: flask

Claims (8)

delete delete delete An ultrasonic generator which uses ultrasonic waves to form a silica sol containing colloidal silica as a main material as droplets of a predetermined size; A heating element installed at one side of the ultrasonic generator to generate an upward airflow so that the droplets are introduced into a vertical reactor through a tube; A vertical reactor for heating the droplets supplied through the tube to a constant temperature to form spherical silica powders; Collector is provided with a filter cloth for collecting the particles; And And an inhaler installed around the collector so that the silica powder passing through the reactor is collected in the collector. Spherical silica powder production apparatus, characterized in that the internal temperature of the reactor is 100 ℃ to 300 ℃. delete delete The method of claim 4, wherein Spherical silica powder production apparatus characterized in that it further comprises a cooling unit for condensing moisture in the droplets that were vaporized in the reactor. The method of claim 4, wherein The tube is a spherical silica powder production apparatus, characterized in that the droplets from the ultrasonic generator is formed to be rotated 180 ° to be introduced into the reactor.