KR20150010224A - Gas scrubber - Google Patents

Abstract

Disclosed is a gas scrubber which is capable of processing waste gas such as semiconductor process gas. A gas scrubber according to the present invention includes a processing chamber unit for processing waste gas; a waste gas supply pipe unit connected to the processing chamber to supply the waste gas to the processing chamber unit; a heat recovery chamber unit partially or entirely surrounding the processing chamber unit; a circular line unit to supply a heat transfer medium to the heat recovery chamber unit and recover the heat transfer medium; and a heating unit disposed to heat the waste gas passing through the waste gas supply pipe unit, wherein the heating unit is connected to the circular line unit to receive heat from the heat transfer medium so that the heat is used to heat the waste gas. In addition, powder is prevented from being accumulated in the chamber or the pipe by prohibiting moisture from being introduced from a wet processing apparatus disposed at the rear end.

Description

Gas scrubber {GAS SCRUBBER}

Field of the Invention The present invention relates to the field of gas treatment, and more particularly, to a gas scrubber for purifying a process gas used in semiconductor manufacturing.

Recently, devices using semiconductor materials such as smart phones and displays are becoming the main products of industrial production. The production of such a semiconductor device includes many processes for generating a large amount of noxious gas.

For example, NH ₄ , ClF ₄ , and SF ₆ are used in semiconductor device manufacturing processes such as doping, etching, deposition, and cleaning. In recent years, the use of fluorine compounds such as PFCs and NF ₃ has been continuously increased .

As a byproduct of the process gas, SiH ₄ , F ₂ , HF, SiF ₄ , ClF ₃ , Cl ₂ , HCl, SO _x F _y and WF ₆ are used. Some of the process gases, including the metal components, are also released in the chamber without being reacted.

A key device used for purifying these toxic gases is called a gas scrubber. In general, a gas scrubber is divided into a wet type and a combustion type.

A wet gas scrubber performs cleaning and cooling by spraying water through the gas passing through the chamber. Such a wet type apparatus has a disadvantage in that it is relatively easy to manufacture and can handle a large capacity but can not process an insoluble gas. The combustion type is a direct combustion type in which the exhaust gas is directly combusted and an indirect combustion type in which the exhaust gas is combusted by passing through a high temperature chamber. In recent years, a large number of mixing methods using a mixture of the above-mentioned wet type and dry type are used.

1A and 1B are diagrams schematically showing a conventional gas scrubber 1 and a gas purifying system employing the gas scrubber 1, respectively.

The gas scrubber 1 is connected to the process equipment 2 through the vacuum pump 3 and the heating jacket 4 in a conventional gas purification system applied to a conventional semiconductor manufacturing process. Also, in the existing system, a high-temperature nitrogen supply unit 5 for supplying high-temperature nitrogen (N ₂ ) to the gas scrubber 1 is connected. The gas scrubber 1, which has received the process gas in this way, processes the process gas, and exhausts the process gas through the duct unit 6. The gas scrubber 1 in the conventional system generally comprises two chambers to recover the exhaust gas from the duct section 6 to perform the secondary treatment.

In the conventional general gas scrubber 1, as shown in the figure, the exhaust pipe 1-3 of the combustion processing unit 1-1 is connected to the wet processing unit 1-2.

Such conventional gas purification systems have a high energy consumption to preheat the process gas. Moreover, since a plurality of the above-described purifying lines (scrubber lines) are connected to each process equipment, the actual energy consumption in the existing system is very high, which is a factor for increasing the manufacturing cost. In addition, these conventional systems have disadvantages in that the processing steps are complicated and the total area occupied by the system is large.

Further, in the conventional gas scrubber 1, the powder generated after the treatment is not properly discharged, and thus the piping or the chamber is clogged. Particularly, since the existing gas scrubber 1 is connected to the wet processing unit 1-2 through the exhaust pipe 1-3, the moisture from the wet processing unit 1-2 is introduced, It is becoming a major cause. Such a problem of the inflow of moisture occurs similarly in the apparatus in which the combustion processing unit 1-1 and the wet processing unit 1-2 are integrally formed as shown in Fig.

Therefore, there is a demand for a gas scrubber that is energy efficient and has a reduced powder build-up.

Korean Patent Application Publication No. 2003-0080447

SUMMARY OF THE INVENTION The present invention provides a low-energy gas scrubber with low energy consumption for solving the above-described conventional problems.

The present invention also provides a gas scrubber capable of efficiently discharging powder generated after treatment.

The present invention also provides a gas scrubber capable of preventing moisture from being introduced from the downstream wet processing apparatus.

The present invention also provides a gas scrubber in which the phenomenon of powder accumulating in the chamber or the piping after the treatment is reduced.

The present invention provides a gas scrubber comprising: a processing chamber portion in which the treatment of waste gas is performed; A waste gas supply pipe portion connected to supply waste gas to the processing chamber portion; A heat recovery chamber portion disposed to surround at least a part of the processing chamber portion; A circulation line part for supplying and recovering the heat transfer medium to the heat recovery chamber part; And a heating unit arranged to heat the waste gas passing through the waste gas supply pipe, wherein the heating unit is connected to the circulation line unit and receives heat from the heat transfer medium to use the waste gas for heating.

The gas scrubber of the present invention includes: a discharge pipe disposed at a lower side of the processing chamber to discharge treated gas to the outside; An exhaust pipe through which the discharge pipe communicates laterally; And a blower blowing cooling air connected to the exhaust pipe at one end.

The gas scrubber of the present invention may further comprise a pressure gauge arranged to measure the wind pressure of the exhaust pipe and a gate valve arranged to adjust the opening degree of the exhaust pipe, And determines the degree of opening of the exhaust pipe.

The gas scrubber of the present invention includes a gas supply tube for generating plasma for supplying a plasma generating gas to the processing chamber; A plasma generator arranged to generate a plasma in the processing chamber portion; An oxidation chamber portion disposed at a lower portion of the processing chamber portion and communicating with the processing chamber portion; And an oxygen supply pipe for supplying oxygen to the oxidation chamber, wherein the discharge pipe is connected to the oxidation chamber.

The process chamber portion comprises an upper chamber and a lower chamber communicated with each other, the heat recovery chamber portion is disposed around the lower chamber, and the waste gas supply pipe portion is connected to the upper chamber.

Wherein the waste gas supply pipe portion is connected to a side portion of an upper chamber housing forming one of the upper chambers of the processing chamber portion and at least one of the individual pipes of the waste gas supply pipe portion is formed so that an angle with an outer surface of the upper chamber housing is perpendicular So that the waste gas is rotated in the processing chamber portion.

Wherein the oxygen supply pipe portion is connected to a side surface portion of the oxidation chamber housing in which at least one individual pipe forms the oxidation chamber portion and at least one individual pipe of the oxygen supply pipe portion has an angle smaller than a right angle with the outer surface of the oxidation chamber housing So that the waste gas is rotated in the oxidation chamber portion.

The gas scrubber of the present invention may include combustion means, which may be combustion and, in this case, are arranged to combust offgas in the process chamber portion. The waste gas supply pipe portion of the combustion gas scrubber includes at least one individual pipe and further includes an inert gas supply pipe for supplying an inert gas to form an inert gas shield layer around the waste gas introduced through the individual pipe of the waste gas supply pipe portion .

According to the present invention, a gas scrubber with high energy efficiency is provided. Such a gas scrubber can recover the heat generated in the processing chamber and use it for heating the waste gas, thereby realizing a low energy scrubber. Further, the gas scrubber of the present invention smoothly discharges the powder by the discharge / exhaust pipe structure using the venturi effect. In addition, the exhaust / exhaust structure of the present invention essentially prevents the moisture from being introduced from the wet processing apparatus disposed at the rear end, thereby solving the problem that the powder is accumulated inside the chamber or inside the pipe to cause clogging. The automatic pressure control mechanism of the blowing pressure adopted by the gas scrubber of the present invention maintains the appropriate wind pressure so that exhaust gas and powder are discharged well and the proper cooling target can be stably maintained. As a result, it is possible to reduce the use of ancillary apparatus such as a heating apparatus, thereby greatly reducing the size of the entire apparatus, and obtaining an effect of cost reduction.

Figs. 1A and 1B are schematic views of a conventional gas scrubber and a gas purifying system employing it.
2 is a cross-sectional view schematically showing a gas scrubber according to a first embodiment of the present invention.
Figure 3 is a schematic plan view of the gas scrubber of Figure 2;
FIG. 4 is a view showing a part of the gas scrubber of FIG. 2; FIG.
Fig. 5 is a schematic view of a gas purifying system employing the gas scrubber of Fig. 2;
6 is a schematic view showing a part of a gas scrubber according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The present invention provides a low energy gas scrubber with high energy efficiency by recovering and utilizing heat generated during plasma generation. In addition, in the gas scrubber of the present invention, since the moisture from the downstream wet processing apparatus is not introduced, the phenomenon of powder accumulation in the chamber and the piping is significantly reduced. Further, the present invention achieves a target of cooling stably as well as satisfactory exhausting by performing cooling blowing with appropriate wind pressure through automatic pressure control. These features of the present invention can be applied to both the plasma scrubber and the combustion scrubber. Hereinafter, the plasma scrubber will be described as the first embodiment, and the combustion scrubber will be described as the second embodiment.

2 is a cross-sectional view schematically showing a gas scrubber 10 according to a first embodiment of the present invention. 3 is a schematic plan view of the gas scrubber 10 of Fig. Figure 4 is a view showing a portion of the gas scrubber 10 of Figure 2; FIG. 5 is a schematic view of a gas purifying system employing the gas scrubber 10 of FIG. 2;

As described above, the gas gas scrubber 10 according to the first embodiment of the present invention is a plasma scrubber.

Referring to the drawings, a gas gas scrubber 10 according to the first embodiment of the present invention includes a processing chamber portion 100 in which waste gas treatment is performed. This processing chamber portion 100 is preferably divided into an upper chamber 110 and a lower chamber 120, which are formed by the respective housings 111, 121. The upper chamber housing 111 and the lower chamber housing 121 can be coupled through a flange coupling method as shown in the figure.

A plasma generating part 112 is provided in the upper chamber housing 111 and a plasma generating gas supplying pipe 113 for supplying a plasma generating gas such as nitrogen or argon is connected. The upper chamber housing 111 is also connected to one or more waste gas supply tubes 114 for supplying waste gases to be treated, such as semiconductor process gases. In the illustrated first embodiment, four individual tubes constitute a waste gas supply tube section 114, which are connected to the side of the upper chamber housing 111 and installed in the process chamber section 100 to cause cyclone rotation of the waste gas do. This will be described in detail below with reference to FIGS. 3 and 4.

The lower chamber housing 121 has a double wall structure in which the side walls are formed by an inner wall 121a and an outer wall 121b. The inside of the inner wall 121a substantially becomes the processing chamber or the reaction chamber, and this communicates with the space of the upper chamber 110. [

Such a processing chamber portion may be referred to as a plasma chamber. The space between the inner wall 121a and the outer wall 121b serves as a heat recovery chamber 130 in which the circulation line portion 160 of the heat transfer medium is connected to supply and recover the heat transfer medium into the heat recovery chamber 130 . The circulation line portion 160 of the heat transfer medium is composed of, for example, a supply pipe and a return pipe. These supply pipes and the return pipe are connected to a heating unit 150 such as a so-called heater jacket, and the heat transfer medium circulating through the circulation line unit 160 is heated by the heating unit 150.

In the gas scrubber 10 according to the first embodiment of the present invention, the waste gas supply pipes 114 are also installed to pass through the heating unit 150, and the waste gas is heated by the heating unit 150. As already mentioned above, when the metal powder, Ti, W, Cu, NH ₄ Cl, and NH ₄ F gases are in a gel state when the temperature is 170 ° C or higher, a hardening phenomenon occurs in the pipe. Therefore, the heating unit 150 must heat the waste gas.

As described above, the heat is recovered through the heat recovery chamber 130 and the waste gas supply pipe 114 is heated, so that the consumed energy is greatly reduced and the apparatus for heating can be greatly reduced.

The oxidation chamber part 140 is disposed below the processing chamber part 100. The oxidation chamber part 140 is formed by connecting the oxidation chamber housing 141 forming the oxidation chamber with the lower chamber housing 121 of the processing chamber part 100 in a flange coupling manner and communicating with the upper processing chamber part 100 do.

The oxidation chamber part 140 is connected to an oxygen supply pipe part 142 for supplying oxygen to the oxidation chamber part. In this case, oxygen is used for oxidation and cooling of the plasma in the first embodiment.

A discharge pipe 161 for discharging the processed gas to the outside is connected to the lower portion of the oxidation chamber part 140. The discharge pipe 161 is connected to a side portion of the exhaust pipe 162 provided separately. A blower 163 for blowing cooling air is disposed at one end of the exhaust pipe 162. This structure generates the venturi effect, so that the treated gas and the powder through the discharge pipe 161 and the exhaust pipe 162 can be easily discharged. Furthermore, because of this structure, since the gas scrubber 10 of the present invention is substantially separated from the wet processing apparatus 50 (see FIG. 5) disposed at the rear end thereof, the moisture from the wet processing apparatus 50 is substantially introduced . Therefore, the phenomenon that the powder is accumulated in the chamber or the pipe due to the inflow of moisture is remarkably reduced.

A pressure gauge 164 disposed to measure the wind pressure of the exhaust pipe 162 and a gate valve 165 installed in the exhaust pipe 162 for opening and closing the exhaust pipe. More preferably, the opening degree of the gate valve 165 is adjustable, so that the opening degree of the exhaust pipe 162 can be determined according to the measured value of the pressure gauge 164. The gate valve 165 can be implemented as a solenoid valve or the like, and the cooling of the desired target value can be stably and continuously maintained by controlling the blowing amount and the wind pressure.

The gas scrubber 10 according to the first embodiment of the present invention also has a mechanism for causing waste gas in the process chamber portion 100 and oxygen in the oxidation chamber portion 140 to undergo cyclone rotation. This cyclone rotation is realized by the coupling structure of the piping, and the coupling structure of the waste gas supply pipe 114 is described as a representative example.

3 is a schematic plan view of the gas scrubber 10 according to the first embodiment of the present invention shown in FIG. 4 is a view showing a part of the gas scrubber 10 according to the first embodiment of the present invention shown in Fig. 2

3 and 4, the waste gas supply tube portion 114 is connected to a side portion of the upper chamber housing 111 in which one or more individual tubes form the upper chamber 110 of the processing chamber portion 100. [ At this time, the individual pipe of the waste gas supply pipe portion 114 is laterally arranged so that an angle (θ) with the outer surface of the upper chamber housing 111 is smaller than a right angle, so that the waste gas introduced into the chamber flows into the processing chamber portion 100, . Such cyclone rotation significantly reduces the accumulation of powder or the like on the inner wall surface of the processing chamber portion 100.

Although not shown, one or more individual tubes of the oxygen supply tube 142 are connected to the side portions of the oxidation chamber housing 141 forming the oxidation chamber portion 140. Likewise, one or more individual tubes of these oxygen supply tubes 142 are laterally arranged so that the angle of the angle with the outer surface of the oxidation chamber housing 141 is less than a right angle, Cyclone rotation is performed. Therefore, even in the oxidation chamber part 140, powder and the like are significantly reduced in the inner wall surface of the chamber.

The gas scrubber 10 according to the first embodiment of the present invention operates as follows, which will be described with reference to FIGS. 2 to 5. FIG.

First, the process gas (SiH ₄ , NF ₃ ) used in the process equipment 30 of the semiconductor manufacturing process is pumped by the vacuum pump 30 and then supplied through the waste gas supply pipe portion 114 passing through the heating portion 150 And is introduced into the processing chamber portion 100 of the scrubber 10. Further, nitrogen (N ₂ ) is introduced into the processing chamber portion 100 through the plasma generating gas supply pipe 113. At this time, the gases to be introduced as described above are subjected to the cyclone rotation in the processing chamber portion 100. A plasma containing N ⁺ , N, F ₂ , Si, H ⁺ , H, H ₂ , N ₂ and the like is generated in the processing chamber part 100 by the discharge of the plasma generating part 112. The heat generated in the processing chamber unit 100 during the plasma generation is transferred to the heat transfer medium in the heat recovery chamber 130. This heat is recovered by the heating unit 150 and the heating of the waste gas introduced into the processing chamber unit 100 . Plasmas of the processing chamber portion 100 are then oxidized by the introduced oxygen to the oxidation chamber portion 140. Similarly, in the oxidation chamber part 140, oxygen introduced through one or more individual pipes of the oxygen supply pipe 142 generates a cyclone rotation to prevent the powder from being accumulated on the inner wall surface. The oxidized gas and powders in the oxidation chamber part 140 are discharged through the discharge pipe 161 and the exhaust pipe 162 and transferred to the wet treatment device 50 at the downstream stage. In this process of discharging / exhausting, outside air is blown into the blower 163 to stably perform discharge and cooling. In particular, an automatic pressure control mechanism including a pressure gauge 164 and a gate valve 165 is employed to automatically adjust the wind pressure to achieve desired target temperature maintenance along with discharge of the powder. The gas delivered to the wet processing apparatus 50 is discharged to the outside through the duct section 60 after the wet processing. Here, the wet processing apparatus 50 may be, for example, a wet electrostatic precipitator.

Hereinafter, a gas scrubber according to a second embodiment of the present invention will be described. The gas scrubber according to the second embodiment is a combustion scrubber. This is because the gas scrubber 10 of the first embodiment has the same or similar elements as those of the gas scrubber 10 of the first embodiment described above, and the description of the same or similar elements will be omitted. For example, in the gas scrubber according to the second embodiment, as described in the first embodiment, the structure for recovering the heat of the heat recovery chamber and used in the heating section, the pipe structure for generating cyclone rotation, and the exhaust gas generating venturi effect The structure can be applied equally.

In the gas scrubber according to the second embodiment of the present invention, the oxidation chamber part 140 may not be separately provided, and the entire chamber may be a processing chamber part. The gas scrubber according to the second embodiment can be used as a cooling chamber that performs a cooling function in the oxidation chamber portion 140. [ Combustion means, such as a burner, disposed to combust the waste gas in the processing chamber portion 100 is disposed to combust the waste gas in the processing chamber. In the gas scrubber of the second embodiment, a heating jacket is disposed in the heat recovery chamber 130 to perform a preheating operation, and heat generated at this time can be recovered by the heating unit 150 and used for heating the waste gas.

Particularly, in the second embodiment, as shown in FIG. 6, when Si is contained in the waste gas, the exhaust gas scrubber 20 is operated to react with oxygen at the outlet of the individual tubes of the waste gas supply pipe portion 214 in the processing chamber portion 100 So that a roughened material can be produced. Therefore, it is possible to further include an inert gas supply pipe 215 for supplying an inert gas such as nitrogen or argon to form the inert gas shield layer around the waste gas introduced through the individual pipe of the waste gas supply pipe 214. This may be realized in the form of a plurality of inert gas supply pipes 215 disposed around each individual pipe of the waste gas supply pipe section 214 or in the form of a double pipe composed of a central pipe for supplying waste gas and an inert gas supply pipe .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

10: Gas scrubber 20: Combustion gas scrubber
30: Process equipment 50: Wet processing device
60: duct part 100: processing chamber part
110: upper chamber 111: upper chamber housing
120: lower chamber 121: lower chamber housing
121a: inner wall 121b: outer wall
130: Heat recovery chamber 140: Oxidation chamber part
141: Oxidation chamber housing 142: Oxygen supply pipe
150: heating section 160: heat transfer medium circulation line section
161: exhaust pipe 162: exhaust pipe
163: blower 164: pressure gauge
165: Gate valve

Claims (9)

As a gas scrubber:
A processing chamber portion in which processing of waste gas is performed;
A waste gas supply pipe portion connected to supply waste gas to the processing chamber portion;
A heat recovery chamber portion disposed to surround at least a part of the processing chamber portion;
A circulation line part for supplying and recovering the heat transfer medium to the heat recovery chamber part; And
And a heating unit arranged to heat the waste gas passing through the waste gas supply pipe,
Wherein the heating unit is connected to the circulation line unit and receives heat from the heat transfer medium and is used for heating the waste gas.
Gas scrubber.
The method according to claim 1,
A discharge pipe disposed at the lower side of the processing chamber and discharging the treated gas to the outside;
An exhaust pipe through which the discharge pipe communicates laterally; And
And a blower for blowing cooling air to one end of the exhaust pipe,
Gas scrubber.
The method of claim 2,
A pressure gauge arranged to measure the wind pressure of the exhaust pipe,
Further comprising a gate valve arranged to adjust the degree of opening of the exhaust pipe,
Wherein the gate valve determines an opening degree of the exhaust pipe according to a measured value of the pressure gauge.
Gas scrubber.
The method according to any one of claims 1 to 3,
A plasma generating gas supply pipe for supplying a plasma generating gas to the processing chamber;
A plasma generator arranged to generate a plasma in the processing chamber portion;
An oxidation chamber portion disposed at a lower portion of the processing chamber portion and communicating with the processing chamber portion; And
And an oxygen supply pipe for supplying oxygen to the oxidation chamber,
Wherein the discharge tube is connected to the oxidation chamber portion.
Gas scrubber.
The method of claim 4,
Wherein the processing chamber portion comprises an upper chamber and a lower chamber communicated with each other,
Wherein the heat recovery chamber portion is disposed around the lower chamber,
And the waste gas supply pipe portion is connected to the upper chamber.
Gas scrubber.
The method of claim 5,
The waste gas supply pipe portion is connected to a side portion of an upper chamber housing in which at least one individual pipe forms the upper chamber of the processing chamber portion,
Wherein at least one individual tube of the waste gas supply tube is laterally connected so that an angle with an outer surface of the upper chamber housing is less than a right angle so that the waste gas rotates within the processing chamber portion.
Gas scrubber.
The method of claim 5,
Wherein the oxygen supply pipe portion is connected to a side portion of the oxidation chamber housing in which at least one individual pipe forms the oxidation chamber portion,
Wherein the at least one individual tube of the oxygen supply tube portion is laterally connected so that an angle with an outer surface of the oxidation chamber housing is less than a right angle so that waste gas rotates within the oxidation chamber portion.
Gas scrubber.
The method according to any one of claims 1 to 3,
And combustion means arranged to burn waste gas in the processing chamber portion.
Gas scrubber.
The method of claim 8,
The waste gas supply pipe portion includes at least one individual pipe,
Further comprising an inert gas supply pipe for supplying an inert gas to form an inert gas shield layer around the waste gas injected through the individual pipe of the waste gas supply pipe section.
Gas scrubber.

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