JP6322502B2 - Exhaust gas treatment equipment - Google Patents

Description

  TECHNICAL FIELD The present invention relates to an exhaust gas treatment facility, and more particularly, to pipe a gas fluid containing silicon dioxide particles derived from a detoxification device for detoxifying the exhaust gas of a semiconductor manufacturing device using a source gas containing silane. It is related with the waste gas treatment equipment transferred to a dust removal device.

  For example, an exhaust gas containing unreacted silane is derived from a semiconductor manufacturing apparatus that uses a source gas mainly containing silane in a semiconductor manufacturing process. The exhaust gas is exhausted to the outside after the silane detoxification process is performed by the detoxification apparatus, and further, the silicon dioxide dust generated by the detoxification process is removed by the dust removal apparatus. Exhaust gas that removes dust accumulated on the inner peripheral surface of the pipe by rapidly introducing a dust pressure feed gas into the pipe through which the gas containing dust such as silicon dioxide flows. Duct equipment has been proposed (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 11-233444

  When nitrogen trifluoride is used in the cleaning process of the semiconductor manufacturing apparatus, strong acid hydrogen fluoride is generated from nitrogen trifluoride in the detoxifying process in the detoxifying apparatus. For the pipes to reach, non-metallic pipes that are not easily corroded by hydrogen fluoride, usually pipes made of vinyl chloride, are often used. When silicon dioxide dust flows in such a pipe made of vinyl chloride, both are charged by friction between vinyl chloride and silicon dioxide, and the dust of silicon dioxide on the inner peripheral surface of the pipe made of vinyl chloride is caused by the action of static electricity. Since it adheres strongly, a strong force is required to remove silicon dioxide.

  For this reason, it is difficult to remove the silicon dioxide dust adhering to the inner peripheral surface of the pipe only by the gas flow. There was a problem with equipment costs and installation area.

  Accordingly, an object of the present invention is to provide an exhaust gas treatment facility capable of suppressing the adhesion and accumulation of silicon dioxide dust on the inner peripheral surface of a pipe with a simple structure.

In order to achieve the above object, the exhaust gas treatment facility of the present invention comprises a detoxification device for detoxifying a gas discharged from a facility using a component containing Si in the molecule, and an exhaust gas discharged from the detoxification device. In an exhaust gas treatment facility equipped with a dust separation device that separates silicon dioxide dust contained therein, as an exhaust gas pipe from the abatement device to the dust separation device, the adhesion and accumulation of the dust on the inner peripheral surface is suppressed. For this purpose, it is characterized by using a metal pipe with an epoxy resin baking finish.

  Furthermore, the exhaust gas treatment facility of the present invention is characterized in that the epoxy resin contains a conductive material, or an antistatic coating is applied on a painted surface on which the epoxy resin is baked.

  Further, the flow rate of exhaust gas in the exhaust gas pipe is 5 to 10 m / s, the facility using a component containing Si in the molecule is a semiconductor manufacturing apparatus using silane as a raw material, the detoxification The apparatus is a combustion type, heater type or plasma type thermal decomposition type abatement apparatus, and has a cooling section for cooling high temperature exhaust gas containing dust subjected to the abatement treatment by gas-liquid contact with water. It is characterized by.

  Furthermore, the humidity of the exhaust gas derived from the cooling unit is RH 90% or less, and the moisture content of the dust is 5% or less.

  According to the present invention, it is possible to suppress adhesion and accumulation of dust on the inner peripheral surface of the pipe by using a metal pipe whose inner peripheral surface is baked with an epoxy resin as a pipe through which silicon dioxide dust flows. it can. That is, the charge amount of vinyl chloride when the dust of silicon dioxide flows in a conventional pipe covered with vinyl chloride is −100 [nC / J], whereas the charge amount of epoxy resin is −32 [nC / J]. nC / J], the difference from +25 [nC / J], which is the charge amount of silicon dioxide, can be reduced, and the adhesion of silicon dioxide dust to the inner peripheral surface of the pipe can be reduced. . As a result, blockage of the piping can be prevented, the maintenance cycle can be extended, and the operating rate of equipment such as a semiconductor manufacturing apparatus can be improved. Moreover, even if a strongly acidic substance such as hydrogen fluoride is generated in the process, the metal pipe can be protected by the coating film of the epoxy resin. Furthermore, the increase in equipment cost is also slight, and it is possible to cope with existing equipment and devices by simply replacing the piping.

It is explanatory drawing which shows one example of the exhaust gas treatment equipment of this invention.

  The exhaust gas treatment facility of the present invention is a device for detoxifying a gas discharged through a vacuum pump 12 from a facility using a component containing Si in a molecule, for example, a semiconductor manufacturing apparatus 11 using silane as a raw material. A harming device 13, a dust separation device 14 for separating silicon dioxide dust contained in exhaust gas discharged from the removal device 13, and an exhaust gas pipe 15 extending from the removal device 13 to the dust separation device 14 are provided. ing.

  In the semiconductor manufacturing apparatus 11, for example, in a semiconductor manufacturing process using a source gas mainly containing silane, a gas containing silane is discharged, and in a cleaning process using nitrogen trifluoride, nitrogen trifluoride and hydrogen fluoride are used. Then, a gas containing nitrogen and silicon tetrafluoride is discharged. These gases discharged from the semiconductor manufacturing apparatus 11 are sucked into the vacuum pump 12 and sent to the abatement apparatus 13.

  The detoxifying device 13 is a method capable of detoxifying silane, nitrogen trifluoride, and silicon tetrafluoride, which are harmful components contained in the gas, such as a thermal oxidative decomposition method, a plasma method, or a combustion method. In such a known detoxification processing system, a cooling section 13a is used that sprays water from a spray nozzle and cools a high-temperature processing gas by gas-liquid contact between water and gas. By the detoxification process by the detoxification device 13, silane is decomposed into silane dioxide and water, nitrogen trifluoride is decomposed into hydrogen fluoride and nitrogen, and silicon tetrafluoride is decomposed into silicon dioxide and hydrogen fluoride. Is broken down into Silicon dioxide generates a large amount of fine particles having a particle diameter of 0.001 mm to 1 mm, particularly a large amount of dust having a 50% particle diameter of about 10 μm. The dust separation device 14 can employ a known dust separation system that can separate and remove the silicon dioxide dust from the gas.

  As the exhaust gas pipe 15, a metal pipe whose inner peripheral surface is baked with an epoxy resin is used. The charge amount of silicon dioxide charged by friction between the silicon dioxide dust and the inner peripheral surface of the pipe is +25 [nC / J], and the charge amount of the epoxy resin is −32 [nC / J]. The charge amount of this epoxy resin is smaller than the charge amount of conventional vinyl chloride, which is -100 [nC / J], and is close to the charge amount of silicon dioxide. Therefore, even if silicon dioxide dust and the inner peripheral surface of the pipe are both charged, epoxy resin can weaken the adhesion of the dust to the inner peripheral surface of the pipe compared to conventional vinyl chloride. The amount of accumulation can be reduced, and dust can be easily removed from the inner peripheral surface of the pipe.

  In particular, by setting the flow rate of the exhaust gas in the exhaust gas pipe 15 to 5 m / s or more, it is possible to suppress the adhesion of dust to the inner peripheral surface of the pipe and to remove the dust attached to the inner peripheral surface of the pipe. Is possible. In addition, in order to obtain a flow velocity exceeding 10 m / s, equipment difficulties may occur.

  On the other hand, when the humidity of the exhaust gas containing dust is high or the moisture content of the dust is high, the dust may adhere to the inner peripheral surface of the pipe due to moisture separately from the charging. By adjusting the air volume and wind speed by introducing air from outside, the humidity of the exhaust gas flowing in the exhaust gas pipe 15 is set to RH 90% or less, and the moisture content of the dust is set to 5% or less. Adhesion can be suppressed. In addition, it is preferable to make humidity and moisture content as low as possible according to the amount of exhaust gas.

  In addition, by using an epoxy resin containing a conductive material as the epoxy resin, or by applying an antistatic coating to the painted surface of the epoxy resin that has been baked, the amount of charge between the inner peripheral surface of the pipe and the silicon dioxide dust Therefore, the adhesion and accumulation of dust can be effectively prevented.

  In this way, the detoxifying device 13 for detoxifying the gas discharged from the semiconductor manufacturing apparatus 11 using silane as a raw material, and the silicon dioxide dust contained in the exhaust gas discharged from the detoxifying device 13 By applying an epoxy resin baking coating to the inner peripheral surface of the exhaust gas pipe 15 between the dust separation device 14 to be separated, the difference in charge amount with silicon dioxide is reduced, and dust adheres to the inner peripheral surface of the pipe. The amount of deposition can be reduced.

  As a result, the exhaust gas pipe 15 can be prevented from being blocked, the maintenance cycle for removing the accumulated dust can be extended, the operating rate of the semiconductor manufacturing apparatus 11 can be improved, and the manufacturing cost can be reduced. . Moreover, the piping which carried out the baking coating of the epoxy resin to the inner peripheral surface can be used not only for the exhaust gas from the abatement apparatus 13 but also for various piping for transferring a gas fluid containing silicon dioxide dust.

  In addition, the equipment which uses the component which contains Si in a molecule | numerator is not restricted to the semiconductor manufacturing apparatus shown by the said example, The abatement apparatus can employ | adopt various types of abatement apparatus. Moreover, the metal piping should just use the stainless steel piping material normally used, and it is also possible to use steel, the product made from aluminum, etc.

  In addition, the epoxy resin is a thermosetting resin that can be cured by forming a cross-linked network with an epoxy group remaining in the polymer, and a generally available epoxy resin coating can be used. Is possible.

DESCRIPTION OF SYMBOLS 11 ... Semiconductor manufacturing apparatus, 12 ... Vacuum pump, 13 ... Detoxification apparatus, 13a ... Cooling part, 14 ... Dust separation apparatus, 15 ... Exhaust gas piping

Claims (7)

A detoxifying device for detoxifying a gas discharged from a facility using a component containing Si in the molecule, and a dust separating device for separating silicon dioxide dust contained in the exhaust gas discharged from the detoxifying device; As an exhaust gas pipe from the abatement apparatus to the dust separation apparatus, a metal pipe that has been baked with an epoxy resin for the purpose of suppressing adhesion and accumulation of the dust on the inner peripheral surface Exhaust gas treatment facility characterized by using   The exhaust gas treatment facility according to claim 1, wherein the epoxy resin contains a conductive material. A detoxifying device for detoxifying a gas discharged from a facility using a component containing Si in the molecule, and a dust separating device for separating silicon dioxide dust contained in the exhaust gas discharged from the detoxifying device; In an exhaust gas treatment facility comprising: Exhaust gas treatment facility characterized by antistatic coating on top .   The exhaust gas treatment facility according to any one of claims 1 to 3, wherein a flow rate of the exhaust gas in the exhaust gas pipe is 5 to 10 m / s.   The exhaust gas treatment facility according to any one of claims 1 to 4, wherein the facility that uses a component containing Si in the molecule is a semiconductor manufacturing apparatus that uses silane as a raw material.   The abatement apparatus is a combustion type, heater type or plasma type pyrolysis type abatement apparatus, and includes a cooling unit that cools high-temperature exhaust gas containing dust subjected to the abatement treatment by gas-liquid contact with water. The exhaust gas treatment facility according to any one of claims 1 to 5, wherein the exhaust gas treatment facility is provided.   The exhaust gas treatment equipment according to claim 6, wherein the humidity of the exhaust gas derived from the cooling unit is RH 90% or less, and the moisture content of the dust is 5% or less.

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