JPH06314645A - Apparatus and method for manufacturing refined air - Google Patents

Abstract

PURPOSE:To provide an apparatus and a method for manufacturing refined air in which a trace amount of activated gas and fine dusts, etc., can be completely removed. CONSTITUTION:Ultrapure water 13 is stored in an absorption tank 8 while holding a predetermined level, primarily refined air 10 in which fine particles are removed is supplied from a plurality of nozzles 11 to the tank 8, the air 10 is brought into contact with the water 13 while agitating the water 13 by an agitator 12, thereby removing dust and activated gas remaining in the air 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and method for producing purified air that does not contain dust or active gas, which is used in a clean room of a semiconductor chip manufacturing plant or for drying semiconductor chips after washing with water, and in particular. The present invention relates to an apparatus and method for further removing residual dust and active gas from air from which fine particles have been removed.

[0002]

2. Description of the Related Art In a conventional apparatus and method for producing purified air, as described in JP-A-63-256116, air from which fine particles have been removed is sent to an absorption tank to obtain ultrapure air in the absorption tank. By contacting with water, the active gas such as ammonia, carbon dioxide gas, and sulfurous acid gas remaining in the air was dissolved and removed in water, and then released from the upper part of the absorption tank.

[0003]

Dust and active gas in clean air used in a clean room of a semiconductor chip manufacturing factory in the manufacture of semiconductor devices that are becoming finer are reduced in product yield and quality. Etc. will be the direct cause. However, it has been extremely difficult to completely remove a small amount of active gas and fine dust with the above-described conventional apparatus and method for producing purified air.

Therefore, according to the present invention, a trace amount of active gas, fine dust, etc. can be completely removed by increasing the contact area, the number of contacts, and the contact time between the air from which fine particles have been removed and ultrapure water. An object of the present invention is to provide an apparatus and a method for producing purified air that can be produced.

[0005]

In order to solve the above-mentioned problems, the apparatus for producing purified air according to the present invention has a method in which fine particles-removed air is brought into contact with ultrapure water to produce dust particles remaining in the air. And an absorption tank for removing the active gas, a stirring device for stirring the ultrapure water, and a plurality of agitating devices for injecting the air from which the fine particles are removed into the ultrapure water stirred by the stirring device. And a nozzle. In that case, the absorption tank further has a sprinkler on the upper part thereof in which the ultrapure water descends while drawing a spiral shape, or a shower in which the ultrapure water descends while scattering in a granular form. It is preferable to further have it on the upper part.

Further, in the method for producing purified air according to the present invention, fine air is removed from ultrapure water in an absorption tank for removing dust and active gas remaining in the air from a plurality of nozzles. And a step of stirring the air injected in this step in the ultrapure water, and after this step, the air is released upward from the ultrapure water in the absorption tank. And discharging the air from the upper part of the absorption tank. In that case, when the air escapes from the ultrapure water in the absorption tank upward, the method further comprises a step of spraying ultrapure water while drawing a spiral shape from the above, or the granular ultrapure water is sprayed from above. It is preferable to further have a step of spraying.

[0007]

In the present invention, when the fine particles-removed air is contacted with ultrapure water to remove dust and active gas remaining in the air, the fine particles-removed air is attached to the absorption tank. By injecting into the ultrapure water in the absorption tank from the plurality of nozzles provided, the air becomes finer and the surface area increases, so that the contact area between the ultrapure water and the air increases. By further stirring the ultrapure water with a stirrer, the air injected into the ultrapure water is retained in the ultrapure water for a long time, and at the same time, the air is further finely divided to form ultrapure water. The contact area can be increased.
Then, from the sprinkler or shower attached to the upper part of the absorption tank, new ultrapure water is drawn in a spiral shape or in a granular shape with respect to the air released through the ultrapure water. By falling while scattering, the active gas and the like in the air can be completely removed.

[0008]

EXAMPLES Examples of the apparatus and method for producing purified air according to the present invention will be described below with reference to FIGS.
1 to 3 are schematic perspective views of an absorption tank according to the embodiment, and FIG. 4 is a diagram illustrating flows of purified air and ultrapure water according to the embodiment.

First, a method for producing ultrapure water will be described with reference to FIG. From the deionized water tank 1, water that has passed through the filter to remove the carbon dioxide gas is passed through a pump through an ion exchange device, an activated carbon filling device, and an engineering plastic foam such as a fluororesin having a size of about 0.1 μm. The ultrapure water is sent to the ultrapure water producing apparatus 2 combined with a filter having a pore size and changed into ultrapure water having an electric resistance of 18 mΩ · cm, and then the ultrapure water is transferred to an absorption tank 8 for removing active air gas. Send in. After that, the ultrapure water which has absorbed the active gas in the air in the absorption tank 8 returns to the pure water tank 1,
The above steps are repeated again.

Next, the structure of the apparatus for producing purified air will be described. As shown in FIG. 1, the absorption tank 8 for removing dust and active gas remaining in the primary purified air 10 from which fine particles have been removed is supplied with ultrapure water 13 into the absorption tank 8. An ultrapure water supply pipe 14 is attached, and the ultrapure water 13 supplied from this pipe is stored in the absorption tank 8 while maintaining a predetermined water level. At the bottom of the absorption tank 8, a stirring device 12 as used in a general washing machine is attached.
In addition, the stirring device 1 is provided on the side surface of the absorption tank 8 toward the inside thereof.
Primary purified air 10 in ultrapure water 13 stirred by 2
A plurality of nozzles 11 having a hole diameter of several mm to several tens of mm are attached, and on another side, ultrapure water 13 that has absorbed dust and active gas in the primary purified air 10 by stirring. An ultrapure water outlet 15 for draining the water is provided.

Next, a method for producing purified air will be described.
In FIG. 4, the contaminated air 9 is replaced by the air compressor 3
By connecting with a filter layer filled with an adsorbent such as activated carbon and finally sending it to an air filter 4 provided with a fine particle removal filter having a pore size of 0.3 μm, the contaminated air 9 is passed through the air filter 4. The primary purified air 10 is supplied to the absorption tank 8. In FIG.
The primary purified air 10 is supplied from the plurality of nozzles 11 to the absorption tank 8
It is injected into the ultrapure water 13 inside. After that, the primary purified air 10 mixed in the ultrapure water 13 is stirred by the stirring device 12 at the bottom of the absorption tank 8. After that, primary purified air 10
Is discharged from the ultrapure water 13 toward the upper part of the absorption tank 8 and is sent to the cooler 5 in FIG. 4, where the supersaturated water is condensed by the cooling and is condensed to 1
Next, it is separated from the purified air 10. After that, the primary purified air 10 is sent to the air heater 6, the moisture is removed by drying, and the secondary purified air (ultra-purified purified air) 18 is obtained by passing through the ultrafine particle removal filter 7.

As another embodiment shown in FIG. 2, an ultrapure water supply pipe 14 is attached to the upper part of the absorption tank 8 and a sprinkler 16 is attached to the tip thereof, so that the ultrapure water is supplied from the sprinkler 16 and the ultrapure water is supplied from the ultrapure water 13. It is preferable to spray on the discharged primary purified air 10. As still another embodiment shown in FIG. 3, a shower 17 may be attached instead of the sprinkler 16 and granular ultrapure water may be sprayed from the shower 17.

[0013]

As described above, according to the present invention, by increasing the contact area, the number of contacts, and the contact time between the air from which fine particles have been removed and ultrapure water, a minute amount of active gas or fine dust can be obtained. Etc. can be completely removed, and the purified air obtained as a result can be used in a clean room or the like to improve product yield and quality.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an absorption tank in an embodiment of an apparatus and method for producing purified air according to the present invention.

FIG. 2 is a schematic perspective view of an absorption tank in another embodiment of the apparatus and method for producing purified air according to the present invention.

FIG. 3 is a schematic perspective view of an absorption tank in still another embodiment of the apparatus and method for producing purified air according to the present invention.

FIG. 4 is a diagram illustrating flows of purified air and ultrapure water in an example of the present invention.

[Explanation of symbols]

 8 Absorption Tank 10 Primary Purified Air 11 Nozzle 12 Stirrer 13 Ultra Pure Water 14 Ultra Pure Water Supply Pipe 15 Ultra Pure Water Discharge Port 16 Sprinkler 17 Shower

Claims (6)

[Claims] 1. An apparatus for producing purified air, wherein an absorption tank for removing dust and active gas remaining in the air by contacting the air from which fine particles have been removed with ultrapure water An apparatus for producing purified air, comprising: a stirrer for stirring, and a plurality of nozzles for injecting the air from which the fine particles have been removed into the ultrapure water stirred by the stirrer. 2. The purified air producing apparatus according to claim 1, wherein the absorption tank has a sprinkler on the upper part thereof for allowing the ultrapure water to drop while drawing a spiral shape. Manufacturing equipment. 3. The purified air manufacturing apparatus according to claim 1, wherein the absorption tank has a shower at an upper portion thereof, which shower drops the ultrapure water while scattering in a granular form. Manufacturing equipment. 4. A method for producing purified air, in which fine particle-removed air is injected from a plurality of nozzles into ultrapure water in an absorption tank for removing dust and active gas remaining in the air. A first step, a second step in which the air injected in the first step is stirred in the ultrapure water, and, after the second step, the air flows in the absorption tank And a third step of discharging the air from the upper part of the absorption tank after the upward removal from the pure water. 5. The method for producing purified air according to claim 4, wherein after the second step, a spiral shape is formed from above with respect to the air released above the ultrapure water in the absorption tank. A method for producing purified air, further comprising a step of spraying ultrapure water while drawing. 6. The method for producing purified air according to claim 4, wherein after the second step, the air that has been degassed upwards from the ultrapure water in the absorption tank is granular from above. A method for producing purified air, further comprising a step of spraying pure water.