KR20110065158A - Adsoption apparatus and method for removing pfcs and cl2 gas of semiconductor etching process - Google Patents

Abstract

PURPOSE: An apparatus and a method for removing perfluorinated compound for the semiconductor etching process and hydrochloric acid are provided to prevent the corrosion of the main duct and danger of the gas leak by preventing the generation of the HCI gas, and to miniaturize the gas removal apparatus. CONSTITUTION: The apparatus for removing perfluorinated compound for the semiconductor etching process and hydrochloric acid includes: multi-layered filter unit(10); a mixing reactor(20); and a anti-condensing system(30). The multi-layered filter unit comprises a plurality of filters which are mutually detached. In the mixing reactor, the mixed response remover is filled. The mixing reactor eliminates the hydrochloric acid gas from the gas passing through the cone multistep filter part. The mixing reactor is connected in the downstream side of the cone multi-layered filter unit. The condensation system for avoiding comprises the cylindrical air inlet port and actuator valve. The condensation system for avoiding is connected in the downstream side of the mixing reactor.

Description

Apparatus and method for removing perfluorinated compound and chlorine gas for semiconductor etching process {ADSOPTION APPARATUS AND METHOD FOR REMOVING PFCs AND Cl2 GAS OF SEMICONDUCTOR ETCHING PROCESS}

The present invention relates to a gas removal apparatus for removing PFCs and Cl ₂ from a waste gas for a semiconductor etching process, and a gas removal method using the same, and more particularly, to miniaturization of a gas processing apparatus, a batch treatment of PFCs gas and Cl ₂ gas, and The present invention relates to a perfluorinated compound and a chlorine gas removal device and method for a semiconductor etching process that prevents the generation of HCl gas to prevent the risk of corrosion and gas leakage of the main duct.

Currently, perfluorocompounds (PFCs) are widely used in chemical vapor deposition, etching, and chamber cleaning processes in the semiconductor industry. For example, CF ₄ , C ₂ F ₆ gas is mainly used in the semiconductor etching process.

Most of these PFCs are very stable inert gases and have very high global warming potential (GWP) because they have a long residence time in the atmosphere and absorb infrared radiation from the earth. Despite the characteristics of PFCs, the use of PFCs in the semiconductor industry continues to increase.

In addition, Cl ₂ gas used during the production of the product is a highly corrosive acid gas, especially when residual Cl ₂ gas reacts with a small amount of water when it enters the main duct after the production of the product. Can be. This corrosion poses a high risk of gas leakage and production equipment shutdown.

Patent No. 719,371 discloses an adsorption plant and method for regenerating high concentrations of PFCs from low concentrations of PFCs gas through adsorption and desorption using a large adsorption tower, which takes a lot of space as a large facility and removes PFCs gas. The device and the Cl ₂ degassing device must be installed separately, and if there is a problem with the adsorption tower, there is a problem that the use of semiconductor equipment must be stopped for a long time.

The present invention has been made to solve the above problems of the prior art, the object of the present invention is to miniaturize the gas treatment device, batch processing of PFCs gas and Cl ₂ gas and prevent the generation of HCl gas to prevent corrosion of the main duct and gas A perfluorinated compound and chlorine gas removal apparatus and method for a semiconductor etching process to prevent the risk of leakage.

In order to achieve the above object, the present invention is a conical multi-stage filter unit equipped with a plurality of filters spaced apart from each other to remove the PFCs gas from the waste gas for etching process; A mixing reactor filled with a mixed reaction remover to remove chlorine gas from the gas passing through the conical multistage filter unit, and connected in communication with a downstream side of the conical multistage filter unit; And a cylindrical air inlet and an actuator valve to prevent condensation of the gas and water passing through the mixing reactor, and a condensation preventing system in communication with a downstream side of the mixing reactor. And a chlorine gas removal device.

According to one aspect of the invention, the conical multi-stage filter unit is equipped with a first to fourth filters.

According to an aspect of the present invention, the first filter to the fourth filter is a disk having a plurality of pores, a mesh network is provided on the upper and lower portions of the disk, PFCs between the upper and the mesh network of the disk The gas remover is filled.

According to an aspect of the present invention, the mixing reactor is a mixture of a mixture of activated carbon powder of 20 to 30 mesh size and zeolite 1: 1 in the form of a pellet of 10mm pellets of the first stage mixed reactant and the mixture of 3mm pellets The second stage mixed reactant molded into the form is filled.

The present invention also includes a first step of removing the PFCs gas by passing the waste gas used in the semiconductor etching process through a conical multi-stage filter unit including a first filter, a second filter, a third filter and a fourth filter; A second step of removing the Cl ₂ gas by passing the waste gas passing through the conical multi-stage filter unit through a mixing reactor including a mixed reactant filler packed with a first stage mixed reaction remover and a second stage mixed reaction remover; And a third step of preventing the condensation by passing the waste gas passing through the mixing reactor through a condensation prevention system including a cylindrical air inlet and an actuator valve. .

As described above, according to the present invention, by providing a gas removal device for removing the PFCs gas and Cl ₂ gas used in the etching process at once, there is an effect to prevent air pollution and global warming, miniaturization of the gas removal device, By preventing the batching of PFCs and Cl ₂ gas and the generation of HCl gas, the risk of corrosion of main duct and leakage of gas can be prevented.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Conical  Multilevel Filter part

The conical multi-stage filter unit 10 according to the present invention is equipped with a plurality of filters.

According to one aspect of the present invention, the conical multi-stage filter unit 10 may be equipped with four filters.

Hereinafter, referring to FIG. 2, a first filter 12 capable of removing particulate matter is positioned at the gas inlet 11 of the conical multistage filter part 10. For example, the first filter may be a disk in which a plurality of pores exist as a stainless material.

The second filter 13 is positioned below the first filter 12 at predetermined intervals. The diameter of the second filter 13 is larger than the diameter of the first filter 12. For example, the second filter 13 may be a disk-shaped double pore plate in which a plurality of pores exist as a stainless material. The upper portion of the pore plate may be filled with a PFCs gas remover in the form of a ball, the mesh net is fixed to the upper and lower portions of the pore plate to prevent the separation of the PFCs gas remover. The PFCs gas remover may comprise a composite metal oxide component containing nickel and chromium.

The third filter 14 is positioned below the second filter 13 at predetermined intervals. The diameter of the third filter 14 is larger than the diameter of the second filter 13. For example, the third filter 14 may be a disk-shaped double pore plate in which a plurality of pores are made of stainless steel. The upper part of the pore plate may be filled with a PFCs gas remover in the form of a ball, and a mesh network is fixed to the upper and lower portions of the upper and lower portions of the pore plate to prevent the PFCs gas remover from being separated. The PFCs gas remover may comprise a composite metal oxide component containing nickel and chromium.

The fourth filter 15 is positioned below the third filter 14 at predetermined intervals. The diameter of the fourth filter 15 is larger than the diameter of the third filter 14. For example, the fourth filter 15 may be a disk-shaped double pore plate in which a plurality of pores are made of stainless steel. The upper part of the pore plate may be filled with a PFCs gas remover in the form of a ball, and a mesh network is fixed to the upper and lower portions of the upper and lower portions of the pore plate to prevent the PFCs gas remover from being separated. The PFCs gas remover may comprise a composite metal oxide component containing nickel and chromium.

The gas outlet 16 of the conical multi-stage filter part may be in the form of a hopper of a light-receiving narrow, and the diameter of the gas outlet 16 is preferably larger than the diameter of the gas inlet 11.

Mixing reactor

Hereinafter, the mixing reactor 20 according to the present invention will be described with reference to FIG. 3. The mixing reactor 20 is cylindrical. For uniform distribution of gas, pore plates 22 and 26 are located at the upper and lower ends of the mixing reactor 20. The pore plates 22 and 26 are mounted at a predetermined distance from the gas inlet 21 and the gas outlet 27, respectively. The gas inlet 21 is in communication with the gas outlet 16 of the conical multistage filter part 10.

Inside the mixing reactor 20, there is a mixed reactant filler part 24 filled with a first mixed reactant and a second mixed reactant. The second stage admixture is stacked on top of the first stage admixture.

Condensation Prevention System

Hereinafter, a condensation prevention system 30 according to the present invention will be described with reference to FIG. 4. A gas inlet 31 is formed at the lower end of the condensation prevention system 30. The gas inlet 31 is in communication with the gas outlet 27 of the mixing reactor 20. The upper end of the condensation prevention system 30 is provided with a cylindrical air intake 33.

The cylindrical air inlet 33 inhales external air when gas is introduced through the gas inlet 31, thereby preventing a temperature change of moisture that may be generated as a carrier gas and a by-product of a gas decomposition process. And condensation of moisture. Typically, since the temperature of the gas exiting the mixing reactor 20 is 22-23 ° C, it is preferable to intake air at about 22-23 ° C.

The cylindrical air intake 33 may be equipped with a fan for taking in the outside air. The outside air taken into the condensation prevention system is discharged to the main duct 40 through the gas outlet 27 together with the gas introduced through the gas inlet 31.

An actuator valve 32 is positioned below the cylindrical air intake 33. The actuator valve 32 automatically shuts off the outside air when the temperature difference between the outside air and the inside gas exceeds a predetermined range. A gas outlet 34 is located below the actuator valve, and the gas outlet 34 is connected to the main duct 40.

PFCs  And Cl ₂  Gas removal efficiency

The above-described degassing apparatus is manufactured as follows to form PFCs and Cl ₂ The removal efficiency of the gas was measured.

The diameters of the first to fourth filters provided in the conical multi-stage filter part 10 were 50 mm, 100 mm, 150 mm, and 200 mm, respectively. The second filter 13 was filled with 2 L of PFCs gas remover in the form of a ball of 3 mm in diameter containing nickel and chromium. The third filter 14 was filled with 4 L of PFCs gas remover in the form of a ball of 5 mm in diameter containing nickel and chromium. The fourth filter 15 was filled with 10 L of PFCs gas remover in the form of a ball having a diameter of 8 mm containing nickel and chromium.

The size of the mixing reactor 20 is 320 mm in diameter and 400 mm in height. In order to minimize the occurrence of the differential pressure and maximize the Cl ₂ gas reaction, the first step of forming a mixture of activated carbon powder and zeolite 1: 1 in the form of pellets of 10mm in the mixing reactor filling part of the mixing reactor 20 The mixed reactant and the second stage mixed reactant were formed by molding the mixture into pellets of 3 mm. The filling amount of the first stage mixed reactant and the second stage mixed reactant is 30L and 40L, respectively. The size of the activated carbon powder and zeolite is 20 ~ 30mesh.

The overall height of the condensation prevention system 30 is 200 mm and the diameter of the air intake is 80 mm. 500 sccm of N ₂ carrier gas, CF ₄ , C ₄ F ₈ , C ₅ F ₈ PFCs gas 2sccm were supplied at a concentration of 1% through the gas inlet 11 of the conical multistage filter unit 10. Next, the removal efficiency of the PFCs gas was measured using an FT-IR analyzer (MIDAC, USA), respectively.

Next, 500 sccm of N ₂ carry gas and ₂ sccm of Cl ₂ gas were supplied at a concentration of 1%, and the removal efficiency of Cl ₂ gas was measured using a gas detector tube (Gastech, Japan).

The results are shown in Table 1 and Table 2.

Sample gas flux
(sccm) Remover size
(mm) Inflow concentration
(%) Remover form S1 CF ₄ 506 3, 5, 8 One ball S2 C ₄ F ₈ 506 3, 5, 8 One ball S3 C ₅ F ₈ 506 3, 5, 8 One ball S4 Cl ₂ 502 3, 10 One Pellet

Sample gas Remover size
(mm) Removal efficiency
(%) S1-A
CF ₄
3 95 S1-B 5 94 S1-C 8 93 S2-A
C ₄ F ₈
3 99 S2-B 5 98 S2-C 8 97 S3-A
C ₅ F ₈
3 99 S3-B 5 98 S3-C 8 97 S4-A
Cl ₂ 3 100 S4-B 10 100

According to the above results, the perfluorinated compound and the chlorine gas removal device for a semiconductor etching process according to the present invention have a smaller removal efficiency than CF ₄ , C ₄ F ₈ , C ₅ F ₈ and Cl ₂ gases compared to conventional devices. It can be confirmed that excellent.

1 is an overall configuration diagram schematically showing a perfluorinated compound and a chlorine gas removal device for a semiconductor etching process according to the present invention,

Figure 2 is an internal configuration of the conical multi-stage filter unit according to the present invention,

3 is a cross-sectional view showing a mixing reactor according to the present invention,

4 is a schematic diagram of a condensation prevention system according to the invention.

* Description of the symbols for the main parts of the drawings *

10: conical multi-stage filter unit 11, 21, 31: gas inlet

12: First filter 13: Second filter

14: third filter 15: fourth filter

16, 27, 34: gas outlet 20: mixing reactor

22, 26: pore plate 24: mixed reagent filler

30: anti-condensation system 32: actuator valve

33: air intake 40: main duct

Claims (5)

Conical multi-stage filter unit equipped with a plurality of filters spaced apart from each other to remove the PFCs gas from the waste gas for the etching process; A mixing reactor filled with a mixed reaction remover to remove chlorine gas from the gas passing through the conical multistage filter unit, and connected in communication with a downstream side of the conical multistage filter unit; And A perfluorinated compound for a semiconductor etching process including a cylindrical air inlet and an actuator valve to prevent condensation of gas and water that has passed through the mixing reactor, and a condensation prevention system in communication with a downstream side of the mixing reactor; Chlorine degassing device. The method of claim 1, The conical multi-stage filter unit is a perfluorinated compound and chlorine gas removal device for a semiconductor etching process, characterized in that the first to fourth filters are mounted. The method of claim 2, The first filter to the fourth filter is a disk having a plurality of pores, a mesh network is installed on the upper and lower portions of the disk, characterized in that the PFCs gas remover is filled between the upper and the mesh network of the disk. Perfluorinated compound and chlorine gas removal apparatus for semiconductor etching processes to be used. The method of claim 1, In the mixing reactor, a first stage mixing reaction of a mixture of activated carbon powder having a size of 30 to 30 mesh and zeolite 1: 1 in a pellet form of 10 mm and a second stage mixing of the mixture in a pellet form of 3 mm Reactant is filled, perfluorinated compound and chlorine gas removal device for semiconductor etching process characterized in that the waste gas is laminated so as to sequentially pass through the first and second stage mixed reactant to reduce the differential pressure generation . A first step of removing the PFCs gas by passing the waste gas used in the semiconductor etching process through a conical multi-stage filter unit including a first filter, a second filter, a third filter, and a fourth filter; A second step of removing the Cl ₂ gas by passing the waste gas passing through the conical multi-stage filter unit through a mixing reactor including a mixed reactant filler packed with a first stage mixed reaction remover and a second stage mixed reaction remover; And a third step of passing the waste gas passed through the mixing reactor through a condensation prevention system including a cylindrical air inlet and an actuator valve to prevent condensation.

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