Processing system and processing method

Abstract

This PFAS detoxification system comprises: a flow path for a waste liquid containing PFAS discharged from a semiconductor fabrication device; one or a plurality of measuring instruments disposed on the flow path to measure the concentration of PFAS contained in the waste liquid; and a control unit. The measuring instrument measures the concentration of PFAS by measuring the pH or the specific resistance value of the waste liquid, and the control unit executes processing in accordance with the concentration of PFAS measured by the measuring instrument.

Description

Processing System and Processing Method

[0001] The present disclosure relates to a processing system and a processing method.

[0002] Patent Document 1 discloses a processing system that detects the concentration of an organic fluorine compound in treated water by generating bubbles in the treated water in a processing water tank and detecting the height of the bubbles generated on the water surface of the treated water.

[0003] Japanese Patent Application Laid-Open No. 2009-255015

[0004] The present disclosure provides a processing system and a processing method capable of performing appropriate processing according to the concentration of an organic fluorine compound in the waste liquid of a semiconductor manufacturing apparatus.

[0005] A processing system according to an aspect of the present disclosure includes a flow path for waste liquid containing an organic fluorine compound discharged from a semiconductor manufacturing apparatus, one or more measuring instruments disposed on the flow path for measuring the concentration of the organic fluorine compound contained in the waste liquid, and a control unit. The measuring instrument measures the concentration of the organic fluorine compound by measuring the pH or specific resistance value of the waste liquid, and the control unit executes processing according to the concentration of the organic fluorine compound measured by the measuring instrument.

[0006] According to the present disclosure, appropriate processing can be performed according to the concentration of an organic fluorine compound in the waste liquid of a semiconductor manufacturing apparatus.

[0007] It is a schematic diagram of the processing system according to the present embodiment. It is a configuration diagram of the PFAS detoxification system shown in FIG. 1. It is a diagram schematically showing a filter and piping configuration related to concentration of resist waste liquid. It is a diagram for explaining an example of the configuration of a measuring instrument. It is a graph for explaining processing according to the life of a filter.

[0008] Hereinafter, embodiments will be described in detail with reference to the drawings. In the description, the same reference numerals are given to the same elements or elements having the same function, and duplicate descriptions are omitted.

[0009] Figure 1 is a schematic diagram of the processing system according to this embodiment. As shown in Figure 1, the processing system comprises a PFAS detoxification system 1 (processing system) and a semiconductor manufacturing apparatus 100. In the processing system, the PFAS detoxification system 1 detoxifies the PFAS discharged from the semiconductor manufacturing apparatus 100. Note that Figure 1 shows a schematic of the configuration of the PFAS detoxification system 1, and some components (for example, the components related to TMAH (tetramethylammonium hydroxide) waste liquid, which will be described later) are not shown. PFAS refers to perfluoroalkyl substances and polyfluoroalkyl compounds (PFAS: Per- and PolyFluoroAlkyl Substances), which are organofluorine compounds.

[0010] PFAS is a compound containing at least one -CF2- or -CF3 aliphatic molecule, and also includes organic polymer compounds such as Teflon (registered trademark). PFAS is found, for example, in foam fire extinguishing agents, plating solutions, aircraft hydraulic fluids, water repellents, floor waxes, etc. PFAS is also found in, for example, textiles, medical equipment, electronic circuit boards, automobiles, food packaging paper, stone materials, flooring, leather, etc. In semiconductor manufacturing processes, non-polymer PFAS is used, for example, in photoresists. Polymeric PFAS is used in wetted parts such as piping, valves, and pumps in semiconductor manufacturing equipment, as well as in anti-reflective coatings.

[0011] PFAS is stable in nature and difficult to decompose. Therefore, PFAS is said to be highly persistent, easily accumulates in living organisms, and is considered highly harmful. The PFAS detoxification system 1 according to this embodiment is a system that suppresses the discharge of PFAS to the outside by detoxifying PFAS discharged from the semiconductor manufacturing apparatus 100. The PFAS detoxification system 1 functions as a treatment system that treats waste liquid discharged from the semiconductor manufacturing apparatus 100. In detail, the PFAS detoxification system 1 is a treatment system that treats resist-containing waste liquid (first waste liquid) discharged from the lithography apparatus 111 (described later).

[0012] As shown in Figure 1, the PFAS detoxification system 1 comprises a concentrator 11, a sulfuric acid treatment tank 12, a cooler 13, and a detoxification device 14. In this embodiment, the PFAS detoxification system 1 is described as a group of devices comprising multiple devices, but the PFAS detoxification system 1 may consist of a single device. The semiconductor manufacturing apparatus 100 comprises a lithography apparatus 111, a cleaning apparatus 112, an etching apparatus 113, and a film deposition apparatus 114. Each component of the semiconductor manufacturing apparatus 100 discharges a substance containing PFAS as it performs the processing. The processing units constituting the PFAS detoxification system 1 may or may not be installed in the same space (location). For example, each processing unit may be installed in the same building as the lithography apparatus 111, cleaning apparatus 112, or etching apparatus 113, or it may be installed outside the building or in an adjacent space. Each processing unit may be installed separately, some inside the building and others outside. Furthermore, the concentrator 11, sulfuric acid treatment tank 12, cooler 13, and detoxification device 14 that are not in use do not need to be permanently installed.

[0013] The lithography apparatus 111 comprises a coating / developing apparatus and an exposure apparatus. The exposure apparatus performs exposure processing on the resist film. Specifically, it irradiates the portion of the resist film (photosensitive film) to be exposed with energy rays by methods such as immersion exposure. The coating / developing apparatus performs a process to form a resist film on the surface of the substrate before exposure processing by the exposure apparatus, and performs development processing on the resist film after exposure processing. The liquid or gas discharged from such a lithography apparatus 111 contains PFAS. For example, resist waste liquid, alkaline waste liquid (positive-type developer) related to development processing, acid waste liquid related to resist stripping, organic exhaust gas, thermal exhaust gas, solidified sublimation material, etc., contain PFAS. In addition, organic solvent waste liquid related to negative-type development processing can be said to be extremely diluted resist waste liquid and contains PFAS, and in this embodiment it may be treated the same as the resist waste liquid described above. In this embodiment, the PFAS contained in the resist waste liquid and the PFAS contained in the positive-type developer will be mainly described. Examples of PFAS contained in resist wastewater include photoacid generators (PAGs), surfactants, or polymers modified with F. The resist wastewater discharged from the lithography apparatus 111 is introduced into the PFAS detoxification system 1.

[0014] The cleaning device 112 performs a cleaning process on the substrate. For example, to remove organic substances such as resist, the cleaning device 112 uses SPM (Sulfuric Acid Hydrogen Peroxide Mixture), which is a mixture of H2O2 and sulfuric acid. For removing metals, the cleaning device 112 uses a mixed aqueous solution (SC2: Standard Clean 2) of H2O2 and hydrochloric acid, and for removing particles, it uses a mixed aqueous solution (SC1) of H2O2 and ammonia. Hot concentrated sulfuric acid alone is also produced during wastewater treatment. The cleaning device 112 discharges SPM wastewater containing PFAS. The SPM wastewater and hot concentrated sulfuric acid discharged from the cleaning device 112 are introduced into the sulfuric acid treatment tank 12. The cleaning device 112 also discharges acidic waste gas containing PFAS. The acidic waste gas discharged from the cleaning device 112 is introduced into the detoxification device 14.

[0015] The etching apparatus 113 performs an etching process to remove the oxide film and thin film along the pattern of the formed resist film. The etching apparatus 113 discharges exhaust gas containing PFAS. The exhaust gas discharged from the etching apparatus 113 is introduced into the detoxification apparatus 14.

[0016] The film deposition apparatus 114 forms a wiring film and an insulating film on a substrate. The film deposition apparatus 114 uses various process gases (PFAS-containing or non-PFAS-containing gases) and discharges exhaust gas. The exhaust gas discharged from the film deposition apparatus 114 is introduced into the detoxification apparatus 14.

[0017] The concentrator 11 concentrates the resist waste liquid containing PFAS discharged from the lithography apparatus 111 of the semiconductor manufacturing apparatus 100. That is, the concentrator 11 concentrates the substrate processing waste liquid from the lithography apparatus 111 as waste liquid containing PFAS. As will be described later, the concentrator 11 has a polymer concentrator 11a and a monomer concentrator 11b (see Figure 2), but here it will be described as concentrator 11 without distinction. The concentrator 11 concentrates the resist waste liquid and separates the solvent contained in the resist waste liquid using, for example, a limit filtration membrane or a reverse osmosis membrane (details will be described later). The concentrated resist waste liquid has high viscosity because it is a concentrated liquid containing polymer. The concentrated resist waste liquid is introduced into the sulfuric acid treatment tank 12. If the alkaline waste liquid discharged from the lithography apparatus 111 is concentrated by the concentrator 11, the alkaline waste liquid may be introduced into the reverse osmosis membrane after neutralization.

[0018] The solvent separated from the resist waste liquid may be used as recycled solvent for cup washing in the semiconductor manufacturing apparatus 100, or it may be collected by a solvent recovery company. Conventionally, when a solvent recovery company attempts to purify the recycled solvent from the resist waste liquid, there is a possibility that they may also collect waste liquid containing confidential substances of the resist manufacturer when performing component analysis. In this respect, as in this embodiment, the resist waste liquid that has passed through the concentrator 11 contains solid components in the concentrated liquid, thus preventing the leakage of confidential information to the solvent recovery company.

[0019] The sulfuric acid treatment tank 12 decomposes and volatilizes the concentrated liquid concentrated by the concentrator 11 using SPM wastewater. In other words, the sulfuric acid treatment tank 12 utilizes the SPM wastewater from the cleaning device 112. In the SPM wastewater, the solvent and polymer undergo decomposition reactions such as oxidation and dehydration, resulting in lower molecular weight (lower viscosity). At this time, the temperature of the SPM wastewater rises due to the exothermic reaction (the temperature of the hot concentrated sulfuric acid in the SPM wastewater rises). PFAS is not basically decomposed, but components such as PAG have low boiling points and volatilize due to the high temperature of the SPM wastewater (especially due to the effect of the hot concentrated sulfuric acid contained in the SPM wastewater). Conventionally, SPM wastewater is treated by adding catalase to suppress foaming, but if the H2O2 component is used up and degassed by reacting with organic matter in the sulfuric acid treatment tank 12, foaming will not occur in the downstream sulfuric acid wastewater, making treatment easier. In addition, the amount of catalase can be reduced. This reaction generates heat, for example, around 300°C, so thermal power generation using the waste heat or steam power generation using steam generated from circulating water used to cool the sulfuric acid treatment tank 12 may be performed. The sulfuric acid waste liquid discharged from the sulfuric acid treatment tank 12 is collected, for example, by a recycling company. The sulfuric acid waste liquid has a higher purity than conventional waste liquid. It is desirable that the sulfuric acid treatment tank 12 be operated in a nitrogen atmosphere, which is an inert gas, to suppress accidental ignition. In addition, the above SPM waste liquid may also be hot concentrated sulfuric acid waste liquid. In the case of hot concentrated sulfuric acid, a dehydration reaction occurs between the solvent and polymer, resulting in a lower viscosity (lower differentiation). At this time, the temperature of the hot concentrated sulfuric acid rises due to an exothermic reaction, causing PFAS, PAG, etc. to volatilize.

[0020] As concentrated resist waste liquid is added to the SPM waste liquid accumulated in the sulfuric acid treatment tank 12 and treated, H2O2 is gradually consumed, and the treatment capacity decreases. After supplying an appropriate amount of concentrated resist waste liquid, the sulfuric acid treatment tank 12 is kept on standby until the reaction settles down and gas generation stops. Since there is a large amount of SPM waste liquid from the washing device 112, it is necessary to treat the SPM waste liquid from the washing device 112 without delay. For this reason, the sulfuric acid treatment tank 12 may be composed of multiple treatment tanks. In this case, preparations such as liquid injection may be carried out in the other treatment tanks while one treatment tank is processing. Alternatively, the liquid may be discharged downstream, for example, from the first treatment tank, then the second treatment tank, then the third treatment tank, depending on the progress of the reaction. If the resist waste liquid is a metal-containing resist, the metal component will precipitate without volatilizing in the same process as described above and will be treated together with the sulfuric acid waste liquid.

[0021] Because SPM wastewater contains hydrogen peroxide, if it is disposed of as wastewater as is, it may foam, putting a strain on the equipment, or the foaming gas may degrade the environment. In this embodiment, however, the residual hydrogen peroxide is effectively utilized, and the foaming gas is burned as fuel in the detoxification device 14, thus reducing the burden on the equipment and the environment.

[0022] The cooler 13 liquefies and collects the gas containing PFAS that has been volatilized by the sulfuric acid treatment tank 12. The cooler 13 separates and collects the gas into low molecular weight gas, which is the gaseous component, and hydrocarbon (HC) extract, which is the liquid component. As shown in Figure 2, when the gas from the sulfuric acid treatment tank 12 is cooled in the cooler 13, the liquefied portion is collected as an HC (Hydrocarbon) extract, and the low molecular weight gas that did not condense is also collected. Since the gas generated from the sulfuric acid treatment tank 12 is treated in a nitrogen atmosphere, it is a mixed gas with nitrogen. Since a mixed gas containing a large amount of nitrogen would require a large amount of processing in the subsequent detoxification device 14, for example, the low molecular weight gas that did not condense in the cooler 13 may be separated into nitrogen and other components using a nano subceramic filter and concentrated.

[0023] Various organic gases and other gases are discharged from the sulfuric acid treatment tank 12 described above. PFAS such as PAG are also discharged as gas. While it is conceivable to directly introduce these gases into the detoxification device 14, gases that become liquid at room temperature can be liquefied in the cooler 13 to improve transportability. If transported without liquefaction, liquid accumulation may occur in the piping, making control difficult. PFAS is present in both the liquefied HC extract and the low-molecular-weight gas that did not condense. The HC extract and low-molecular-weight gas are introduced into the detoxification device 14. To further improve gas transportability, all gases, including the low-molecular-weight gas, may be liquefied before being introduced into the detoxification device.

[0024] The detoxification device 14 detoxifies the substance after treatment by the cooler 13. The detoxification device 14 may also be a combustion detoxification device that burns the substance after treatment by the cooler 13. The detoxification device 14 incinerates the HC extract and low molecular weight gas introduced from the cooler 13. Since most of the HC extract is hydrocarbons, it can be burned as fuel. Similarly, since most of the low molecular weight gas is hydrocarbons with 10 or fewer carbon atoms, it can also be burned as fuel. Conventionally, propane gas or city gas is used as fuel in combustion detoxification devices, but since HC extract and the like are used as fuel as described above, the amount of propane gas and the like can be reduced.

[0025] Furthermore, the detoxification device 14 may simultaneously burn and detoxify the exhaust gas introduced from the etching device 113, the exhaust gas introduced from the film deposition device 114, and the acid waste gas introduced from the cleaning device 112. These gases are exhaust gases containing PFAS used in each device. By burning and detoxifying these gases simultaneously, the amount of propane gas, etc., can be further reduced. In addition, electricity may be generated by burning the gases using an internal combustion engine such as a gas turbine during the burning process. The detoxified gases such as carbon dioxide may be recovered and used in the synthesis of organic substances such as formic acid and methanol. The detoxification device 14 may also be a subcritical treatment system that performs subcritical treatment on the substances after treatment by the cooler 13, or a supercritical treatment system that performs supercritical treatment. Furthermore, the detoxified waste gas may be treated through a scrubber device (a device that washes the exhaust gas with water, neutralizes it with chemicals, or adsorbs it and releases it into the atmosphere) to produce scrubber water containing F ions and waste gas. The scrubber water can be reacted with calcium to produce calcium fluoride or fluorite. Fluorite is a starting material for fluorine compounds, and its resource can be recycled.

[0026] Next, the details of the PFAS detoxification system 1 shown in Figure 1 will be explained with reference to Figure 2. Figure 2 is a diagram of the configuration of the PFAS detoxification system 1 shown in Figure 1. In Figure 2, components that were omitted from Figure 1 (such as components related to TMAH waste liquid) are also shown.

[0027] The PFAS detoxification system 1 further comprises a waste liquid supply channel 15, a polymer filter 301, a polymer concentrator 11a, and a monomer concentrator 11b. The PFAS detoxification system 1 further comprises a circulation channel 16. The PFAS detoxification system 1 further comprises a first filtrate channel 17a, a second filtrate channel 17b, a third filtrate channel 18, a fourth filtrate channel 19, a first storage tank 20xa, a second storage tank 20xb, and a third storage tank 20y. The PFAS detoxification system 1 further comprises a bypass channel 302. The PFAS detoxification system 1 further comprises a first gas filter 22, a vacuum pump 23, and a distiller 24. The PFAS detoxification system 1 further comprises a second gas filter 25. The PFAS detoxification system 1 further comprises a waste liquid supply channel 26, a concentrator 27, a circulation channel 28, a developer channel 29, a regenerated developer storage section 30, a developer processing tank 31, a third gas filter 32, and a generator 33. The PFAS detoxification system 1 further comprises a backflow liquid storage section 35. The PFAS detoxification system 1 further comprises a discharge channel 37. The PFAS detoxification system 1 further comprises an SPM supply channel 38.

[0028] The resist waste liquid containing PFAS discharged from the lithography apparatus 111 flows through the waste liquid supply channel 15 and into the polymer filter 301 provided in the waste liquid supply channel 15. The polymer filter 301 separates the resist waste liquid into a polymer concentrate containing polymer (high molecular weight component) at a predetermined concentration or higher, and a monomer concentrate containing monomer (low molecular weight component) at a predetermined concentration or higher without containing polymer at a predetermined concentration or higher. The polymer concentrate may contain, for example, 20 to 60% by weight of polymer. The monomer concentrate may contain, for example, 2 to 30% by weight of monomer. The polymer filter 301 is a filter with a coarser mesh than the hollow fiber or ceramic filter (filter 39, etc.) used to extract the filtrate (solvent) described later. The polymer concentrate separated by the polymer filter 301 passes through the polymer concentrator 11a and is stored in the sulfuric acid treatment tank 12. Furthermore, the monomer concentrate separated by the polymer filter 301 is stored in the monomer concentrator 11b. Thus, the monomer concentrator 11b is a storage unit for storing the monomer concentrate.

[0029] The circulation channel 16 is a circulation channel connected to the monomer concentrator 11b, and a filter 39 for removing polymer is provided in the middle of the channel. The filter 39 is, for example, a hollow fiber filter or a ceramic filter. The ceramic filter is a filter with excellent chemical resistance to acidic liquids. The monomer concentrate is concentrated by the provision of the filter 39. The filtrate (solvent) that has passed through the filter 39 flows through the first filtrate channel 17a and is stored in the first storage tank 20xa. Such filtrate is a low-concentration PFAS solution. The first storage tank 20xa is a storage section connected to the first filtrate channel 17a for storing the filtrate. The second filtrate channel 17b is a channel connecting the first storage tank 20xa and the second storage tank 20xb. A filter 40a is provided in the second filtrate channel 17b. The filter 40a is, for example, an ion exchange resin filter. The presence of filter 40a allows the filtrate that passes through filter 40a to be a solution with a low PFAS content. The filtrate (solvent) that passes through filter 40a flows through the second filtrate channel 17b and is stored in the second storage tank 20xb. The second storage tank 20xb is connected to the third filtrate channel 18 and is a storage section for storing filtrate. The third filtrate channel 18 is a channel connecting the second storage tank 20xb and the third storage tank 20y. Filter 40b is provided in the third filtrate channel 18. Filter 40b is, for example, an ion exchange resin filter. The presence of filter 40b allows the filtrate that passes through filter 40b to be a solution that contains almost no PFAS. The filtrate that passes through filter 40b flows through the third filtrate channel 18 and is stored in the third storage tank 20y. Such filtrate can be used as a regenerating solvent and flows to the outside from the fourth filtrate channel 19 downstream of the third storage tank 20y.

[0030] The filtrate may, for example, be introduced (backflowed) from the outlet side of the polymer filter 301 via the third filtrate channel 18 and the bypass channel 302. This can eliminate clogging of the polymer filter 301 with polymer components, etc. Such backflow of the filtrate may be performed, for example, by gas pressurization or by a liquid delivery unit such as a pump. Since polymer solutions are highly concentrated and viscous, washing them with a solvent would require a large amount of solvent, or other methods would require treatments such as UV irradiation, oxidation with ozone, or plasma irradiation. In this respect, the method of backflowing the filtrate eliminates the need to prepare a separate solvent or perform UV irradiation, and allows for simple and appropriate cleaning of the polymer filter 301.

[0031] The monomer concentrator 11b, circulation channel 16, filters 39, 40a, 40b, first filtrate channel 17a, first storage tank 20xa, second filtrate channel 17b, second storage tank 20xb, third filtrate channel 18, etc. constitute a low molecular weight component processing section. The low molecular weight component processing section performs a process to increase the concentration of low molecular weight components such as PFAS in the monomer concentrate separated by the polymer filter 301. In particular, the circulation channel 16 and filter 39 of the low molecular weight component processing section function as a circulating filtration mechanism that circulates the monomer concentrate to filter out low molecular weight components. Furthermore, the filters 40a, 40b, first filtrate channel 17a, first storage tank 20xa, second filtrate channel 17b, second storage tank 20xb, third filtrate channel 18, etc. function as a purification mechanism that removes PFAS from the filtrate after it has passed through the circulating filtration mechanism.

[0032] Furthermore, the components downstream of the waste liquid supply channel 15, such as the polymer filter 301 and the low molecular weight component processing unit, may be provided separately for each type of solvent contained in the waste liquid.

[0033] The polymer concentrate flows into the sulfuric acid treatment tank 12 via the polymer concentrator 11a. In the sulfuric acid treatment tank 12, the polymer concentrate is decomposed and volatilized by the SPM waste liquid. This causes decomposition reactions such as oxidation and dehydration, resulting in the decomposition into gases containing carbon monoxide, carbon dioxide, nitrogen, water vapor, hydrocarbon gases, and PFAS. The gases released in this process reach temperatures of 100°C or higher. The gases volatilized in the sulfuric acid treatment tank 12 are then separated by the first gas filter 22. The first gas filter 22 separates the gases volatilized in the sulfuric acid treatment tank 12 into PFAS-rich gas and PFAS-removed gas. The first gas filter 22 is, for example, a permeable vaporization filter, or it may be a ceramic filter. The first gas filter 22 is heated to a higher temperature than the concentrate before decomposition due to the heat generated in the sulfuric acid treatment tank 12. The first gas filter 22 may be located in the same space as the sulfuric acid treatment tank 12, or it may be connected to the sulfuric acid treatment tank 12 by a conductive member such as metal, thereby receiving the heat generated in the sulfuric acid treatment tank 12. In this embodiment, a PFAS-rich gas is a gas in which the concentration of PFAS is higher than that of the gas before being affected by the predetermined action. Here, separation by the first gas filter 22 corresponds to the predetermined action. In this embodiment, the predetermined action is not limited to separation by the first gas filter 22; if a PFAS-rich gas is generated, the action that causes it to be generated can be said to be the predetermined action.

[0034] The first gas filter 22, which is a permeation vaporization filter, is a filter that separates gases by utilizing the difference in momentum caused by differences in molecular weight. Specifically, the first gas filter 22 allows gases with relatively small molecular weights (nitrogen, carbon monoxide, carbon dioxide, water vapor, etc.) to pass through (flow to the downstream side) while preventing gases with relatively large molecular weights (PFAS, hydrocarbons) from passing through, for example, by reducing the pressure on the downstream side. This makes it possible to roughly separate PFAS-rich gas from gas from which PFAS has been removed.

[0035] The vacuum pump 23 is a pump that reduces the pressure downstream of the first gas filter 22, thereby enabling the separation of gas by the first gas filter 22 as described above. The cooler 13 liquefies and collects the gas containing PFAS. The collected liquid and gas are stored in the distiller 24. The liquid PFAS and hydrocarbons, as well as the gaseous PFAS and hydrocarbons (and ozone, which will be described later), are introduced from the distiller 24 to the detoxification device 14.

[0036] In the PFAS detoxification system 1, outside air is taken in and separated into nitrogen and oxygen by the second gas filter 25. That is, the second gas filter 25 separates the outside air into a gas with a higher nitrogen concentration than air (simply referred to here as nitrogen) and a gas with a higher oxygen concentration than air (simply referred to here as oxygen). The second gas filter 25 then supplies nitrogen to the sulfuric acid treatment tank 12. This suppresses ignition in the sulfuric acid treatment tank 12. The second gas filter 25 also supplies oxygen to the detoxification device 14. This promotes combustion in the detoxification device 14. Ozone generated from the oxygen mentioned above may also be supplied to the detoxification device 14. Such ozone may be supplied to the distiller 24 and introduced into the detoxification device 14, or it may be introduced directly into the detoxification device 14. The method for generating ozone from oxygen may be, for example, UV irradiation or electrical discharge.

[0037] In the PFAS detoxification system 1, for example, TMAH waste liquid, which is a positive-type developer, is introduced from the lithography apparatus 111. Then, in the PFAS detoxification system 1, the TMAH waste liquid discharged from the lithography apparatus 111 of the semiconductor manufacturing apparatus 100 is concentrated in the concentrator 27. Furthermore, the first concentrated solution, which is a concentrated positive-type developer concentrated in the concentrator 27, is decomposed and volatilized in the developer processing tank 31.

[0038] The waste liquid supply channel 26 is a supply channel that supplies TMAH waste liquid introduced from the lithography apparatus 111 to the concentrator 27. The waste liquid supply channel 26 and the waste liquid supply channel 15 that supplies resist waste liquid to the concentrator 11 are provided separately from each other. The waste liquid supply channel 26 is equipped with a filter 41 that removes polymers. Thus, the filter 41 is a filter for developer waste liquid that removes polymers from the TMAH waste liquid. The circulation channel 28 is a circulation channel connected to the concentrator 27, and a filter 42 for increasing the concentration of PFAS is provided in the middle of the channel. The developer liquid that has passed through the filter 42 (de-PFAS developer liquid) passes through the developer liquid channel 29 and is stored in the regenerated developer liquid storage section 30. Such a developer liquid can be used as regenerated developer liquid. Thus, the filter 42 is a positive developer waste liquid processing unit that separates the TMAH waste liquid into PFAS concentrated developer liquid and de-PFAS developer liquid. The PFAS-free developer solution may be backflowed into the filter 41 from the secondary side. The backflow liquid storage section 35 is a developer filter cleaning liquid chamber that stores the liquid that has flowed back and passed through the filter 41 in this manner.

[0039] The concentrated solution obtained in the concentrator 27 is supplied to the developer treatment tank 31 via the concentrated solution flow path 45. The developer treatment tank 31 is located in contact with the sulfuric acid treatment tank 12 described above. Specifically, the developer treatment tank 31 is positioned to surround the sulfuric acid treatment tank 12 from below. As a result, the developer treatment tank 31 receives heat from the sulfuric acid treatment tank 12, and this heat can decompose and volatilize the first concentrated solution. Note that the method of decomposing the first concentrated solution is not limited to heat; for example, the first concentrated solution may be decomposed by exposure to microorganisms. Furthermore, the first concentrated solution may be used as a cooling solvent for the SPM in the sulfuric acid treatment tank 12.

[0040] In the developer treatment tank 31, TMAH decomposed by heat (for example, around 140°C) is broken down into trimethylamine and dimethyl ether. These gases can be used as fuel in the detoxification device 14. PFAS is not decomposed by heat and is released as a gas, which is then burned in the detoxification device 14. The gas released from the developer treatment tank 31 contains nitrogen, water vapor, hydrocarbons, trimethylamine, dimethyl ether, PFAS, etc. The third gas filter 32, for example by reducing the pressure on the downstream side, allows relatively low molecular weight gases (nitrogen, water vapor, etc.) to pass through (to the downstream side) while preventing relatively high molecular weight gases (trimethylamine, dimethyl ether, PFAS, hydrocarbons) from passing through. This allows for the general separation of PFAS-rich gas from PFAS-removed gas. Nitrogen and water vapor are released outside the system. The released water vapor is converted back into water in the generator 33, and electricity can be generated using the pressure difference. The gas containing PFAS, etc., that is sent to the detoxification device 14 may be compressed before being sent to the detoxification device 14.

[0041] The detoxification device 14 may have a combustion chamber that mixes and burns the gas vaporized by the developing solution treatment tank 31 and the gas vaporized by the sulfuric acid treatment tank 12. As described above, the PFAS foam solution may be introduced into the detoxification device 14 in the form of a mist. In this case, the PFAS foam solution is introduced into the detoxification device 14 together with an oxygen-free gas. The oxygen-free gas here may include various gases generated in the PFAS detoxification system 1.

[0042] In the sulfuric acid treatment tank 12, when the reaction between the resist concentrate and the SPM waste liquid proceeds, the hydrogen peroxide in the SPM is deactivated, and the reaction ability is significantly reduced. At this time, the SPM becomes concentrated sulfuric acid and can cause a dehydration reaction, but the carbonization of organic substances proceeds and the liquid changes color to yellow or brown. Therefore, for example, when the liquid turns yellow, the SPM waste liquid is discharged from the discharge channel 37. At this time, the filter 43 provided in the discharge channel 37 filters the carbide. The discharged SPM waste liquid has no hydrogen peroxide, and the purity of sulfuric acid is increased by filtering with the filter 43, so it can be used as recycled sulfuric acid.

[0043] When supplying new SPM waste liquid to the sulfuric acid treatment tank 12, a part of the SPM waste liquid can be made to flow in from the outlet side of the filter 43 to wash the filter 43 that has trapped the carbide. That is, the SPM waste liquid may be made to flow through the channel connected to the outlet of the filter 43 among the SPM supply channels 38 for supplying new SPM waste liquid to the sulfuric acid treatment tank 12, so that the SPM waste liquid reacts with the carbide trapped by the filter 43. As a result, the carbide trapped by the filter 43 becomes carbon dioxide and is exhausted, and the filter 43 is washed.

[0044] Here, as described above, the resist waste liquid (the first waste liquid containing resist) discharged from the lithography apparatus 111 is concentrated through a plurality of filters and piping configurations. FIG. 3 is a diagram schematically showing the filter and piping configuration related to the concentration of the resist waste liquid. In FIG. 3, only a part of the configuration shown in FIG. 2 is shown, and configurations not shown in FIG. 2 are also shown.

[0045] As shown in Figure 3, the resist waste liquid flowing through the waste liquid supply channel 15 is pumped by the pump 151 and flows into the polymer filter 301. The polymer filter 301 separates the resist waste liquid into a polymer concentrate (high molecular weight solution) having a polymer (high molecular weight component) at a predetermined concentration or higher, and a monomer concentrate (low molecular weight solution) having a monomer (low molecular weight component) at a predetermined concentration or higher. The polymer filter 301 is located upstream of the filter 39 (first filter).

[0046] The polymer concentrate separated by the polymer filter 301 flows through the channel 72 and is stored in the polymer concentrator 11a. The monomer concentrate separated by the polymer filter 301 is stored in the monomer concentrator 11b (third storage unit), which is located upstream of the filter 39 and stores waste liquid sent toward the filter 39, and then flows through the circulation channel 16. The monomer concentrate flowing through the circulation channel 16 is pumped by the pump 161 and flows into the filter 39 (first filter). The pump 161 (pressurization unit) pressurizes the waste liquid in the channel. The filter 39 is located in the circulation channel 16 and is a filter that separates the resist waste liquid (more specifically, the monomer concentrate concentrated from the resist waste liquid) into liquids with different component concentrations. The filter 39 is, for example, a hollow fiber or ceramic filter and is a filter that separates the monomer concentrate into a monomer concentrate having monomers above a predetermined concentration and a filtrate which is a low-concentration PFAS solution that does not have monomers above a predetermined concentration. The monomer concentrate (waste liquid containing the collected material collected by the filter 39) separated by the filter 39 flows into the flow path 71. In Figure 2, the filtrate-related components included the first storage tank 20xa, the second storage tank 20xb, the first filtrate flow path 17a, the second filtrate flow path 17b, and the filter 40a, but for the sake of simplicity, these are omitted here and referred to simply as the storage tank 20x and the filtrate flow path 17. The storage tank 20x is located downstream of the filter 39 in the flow path and is the first storage section that stores the filtrate, which is the waste liquid that has permeated through the filter 39.

[0047] The filtrate (the "filtrate 1" in FIG. 3) sorted by the filter 39 is stored in the storage tank 20x, and further flows through the filtrate flow path 17. The filtrate flowing through the filtrate flow path 17 is sent by the pump 171 and flows into the filter 40b (second filter). The filter 40b is arranged downstream of the storage tank 20x in the flow path. The filter 40b is, for example, an ion exchange resin filter. The filtrate that has passed through the filter 40b is a solution that hardly contains PFAS. The filtrate (the "filtrate 2" in FIG. 3) that has passed through the filter 40b flows through the third filtrate flow path 18 and is stored in the third storage tank 20y. The third storage tank 20y is arranged downstream of the filter 40b in the flow path and is a second storage part that stores the waste liquid that has passed through the filter 40b.

[0048] As shown in FIG. 3, in addition to the above-described configuration, the PFAS detoxification system 1 includes a control unit 10, a measuring device 400, a valve 501, back pressure valves 601, 602, 603, and pressure gauges 701, 702, 703. Further, the PFAS detoxification system 1 includes the above-described waste liquid supply path 15, circulation flow path 16, filtrate flow path 17, third filtrate flow path 18, flow path 71, and flow path 72 as the flow path of the waste liquid containing PFAS discharged from the semiconductor manufacturing apparatus 100.

[0049] The measuring instrument 400 is positioned on the flow path of the waste liquid and includes multiple sensors that measure the concentration of PFAS contained in the waste liquid. The measuring instrument 400 measures the concentration of PFAS by measuring the pH, resistivity (Ω), or conductivity (S (= 1 / Ω) / m) of the waste liquid. Since PFAS is generally an acidic substance, its concentration can be estimated (measured) by measuring the pH. In addition, for ionic substances, the resistivity and conductivity change. For example, by correlating the pH and resistivity with concentrations measured in advance by a liquid chromatography-mass spectrometer, it becomes possible to measure the concentration of PFAS based on pH, etc. The measuring instrument 400 may measure at least one of the pH, resistivity, and conductivity of at least one of the stock solution, filtrate, and concentrated solution. As described later, by measuring the pH, etc. upstream and downstream of the filter 39 and monitoring the change in PFAS concentration over time, the timing of replacement of the filter 39 can be estimated. The measuring instrument 400 is configured to include, for example, four measuring sensors 401, 402, 403, and 404.

[0050] The measuring sensor 401 (second measuring sensor) is located upstream of the filter 39 in the flow path, for example, in the monomer concentrator 11b. The measuring sensor 401 measures the PFAS concentration of waste liquid, which has a relatively high PFAS concentration, before PFAS is collected by the filter 39. The measuring sensor 402 (first measuring sensor) is located downstream of the filter 39, for example, in the storage tank 20x. The measuring sensor 402 measures the PFAS concentration of waste liquid, which has a relatively low PFAS concentration, after PFAS has been collected by the filter 39.

[0051] Figure 4 illustrates an example of the configuration of a measuring instrument (in this case, a measuring sensor 402). In the example shown in Figure 4, the measuring sensor 402 is attached to the lower end of an arm 800 that can move up and down, and is configured to switch between a state where it is immersed in the waste liquid and a state where it is outside the waste liquid by moving up and down in accordance with the arm 800. Here, the resist waste liquid is basically an organic solution and is in a state where it does not easily ionize. Also, much of the PFAS in the resist waste liquid has not been exposed to light and is therefore not ionized. In this respect, pH is difficult to measure because it measures the concentration of H+. Similarly, resistivity and conductivity are also difficult to measure because they measure the conductivity of the liquid and are therefore not possible in a state where they are not ionized. Therefore, the measuring sensor 402 collects a small amount of waste liquid while immersed in it, ionizes the PFAS that has been exposed to light when it is outside the waste liquid, and increases the concentration by volatilizing the target chemical solution by applying wind, temperature, or vacuum. By this method, pH and other parameters can be appropriately measured using the measuring sensor 402. Furthermore, if the liquid is in a flow path, a small amount of liquid can be collected from the pipe for measurement, or a separate flow path can be provided for measurement.

[0052] The measuring sensor 403 (fourth measuring sensor) is located in the flow path, specifically in the flow path 71, where waste liquid containing the collected material from the filter 39 flows in. The measuring sensor 403 measures the PFAS concentration in the waste liquid for monitoring the PFAS concentration. The measuring sensor 404 (third measuring sensor) is installed in the third storage tank 20y. The measuring sensor 404 measures the PFAS concentration in the filtrate to confirm that the filtrate downstream of the filter 40b does not contain PFAS (or contains a negligibly small amount).

[0053] The measuring sensors 401, 402, 403, and 404 periodically measure the pH, resistivity (Ω), or conductivity (information for estimating the concentration of PFAS) of the waste liquid and transmit it to the control unit 10.

[0054] Back pressure valves 601, 602, and 603 are pressure regulating valves in the flow path. Back pressure valve 601 is located in flow path 72. Back pressure valve 602 is located in flow path 71. Back pressure valve 603 is located in the third filtrate flow path 18.

[0055] Pressure gauges 701, 702, and 703 are devices for measuring the pressure in the flow path. Pressure gauge 701 measures the pressure in flow path 72. Pressure gauge 702 measures the pressure in flow path 71. Pressure gauge 703 measures the pressure in the third filtrate flow path 18.

[0056] The control unit 10 performs processing according to the concentration of PFAS contained in the waste liquid measured by the measuring instrument 400 (measuring sensors 401, 402, 403, 404).

[0057] The control unit 10 may, for example, perform processing according to the concentration difference, which is the difference between the PFAS concentration in the wastewater upstream of the filter 39 measured by the measuring sensor 401 and the PFAS concentration in the wastewater downstream of the filter 39 measured by the measuring sensor 402. This concentration difference increases as the PFAS collection capacity of the filter 39 increases. The control unit 10 may, for example, output an alert if the concentration difference becomes smaller than a predetermined value, indicating that the collection capacity (PFAS removal rate) of the filter 39 has deteriorated (it is time to replace it).

[0058] The control unit 10 may output an alert if the PFAS concentration measured by the measuring sensor 402 is above a predetermined threshold. This allows the control unit to output an alert if the PFAS concentration is high downstream of the filter 39 and the collection efficiency of the filter 39 is deteriorating.

[0059] The control unit 10 may control the pressurizing unit so that waste liquid that has flowed back into the filter 39 from the outlet side (downstream side) is present when the concentration difference between the PFAS concentration measured by the measuring sensor 401 and the PFAS concentration measured by the measuring sensor 402 is greater than or equal to a predetermined threshold. The pressurizing unit here refers to any unit that pressurizes the waste liquid in the flow path to cause it to flow back into the flow path, and may be a pump 161 or other pressurizing unit (not shown).

[0060] The control unit 10 may estimate the lifespan of the filter 39 according to the PFAS concentration measured by the measuring sensor 402, identify a processing timing corresponding to the lifespan, and perform a predetermined process (for example, outputting an alert) at that processing timing. Alternatively, the control unit 10 may estimate the lifespan of the filter 39 according to the PFAS concentration measured by the measuring sensor 402 and the PFAS concentration measured by the measuring sensor 401, identify a processing timing corresponding to the lifespan, and perform a predetermined process at that processing timing.

[0061] Figure 5 is a graph illustrating the processing according to the lifespan of the filter 39. In Figures 5(a) to 5(c), the horizontal axis represents time, and the vertical axis represents the PFAS concentration measured by the measuring sensor 402. As shown in Figure 5(a), the PFAS concentration of the filtrate measured by the measuring sensor 402 increases over time. This is because the collection capacity of the filter 39 deteriorates over time. The control unit 10 estimates the lifespan of the filter 39 from the relationship between the passage of time and the PFAS concentration as shown in Figure 5(a), and determines the timing for replacing the filter 39 according to its lifespan. This replacement timing is the processing timing according to the lifespan, and is, for example, the timing to prompt the user to replace the filter by outputting an alert. By setting the PFAS concentration at the replacement timing as a threshold, it is possible to determine whether or not the threshold has been reached and perform appropriate processing (such as outputting an alert) at the appropriate timing. The example in Figure 5(a) shows an example where the PFAS concentration of the stock solution is constant.

[0062] As shown in Figure 5(b), for example, the PFAS concentration of the stock solution may increase during the process. In this case, as shown in Figure 5(b), the time it takes to reach the threshold becomes shorter, and the timing of replacement changes. Alternatively, the threshold may be set by anticipating the threshold from the expected PFAS concentration of the stock solution, or by estimating the maximum concentration contained in the stock solution from the training data. When changing the threshold, the timing of replacement may be determined from the training data of the relationship between the PFAS concentration upstream of the filter 39 and the filtrate, and the threshold may be changed accordingly.

[0063] As shown in Figure 5(c), the PFAS concentration leaking from the filter 39 is measured to estimate the lifespan of the filter 39. Before reaching the end of its lifespan, the filter 39 is replaced or refreshed.

[0064] The control unit 10 may control the pressurizing unit so that the amount of waste liquid processed by the filter 39 decreases as the estimated lifespan of the filter 39 approaches its end. The pressurizing unit here can be any unit that pressurizes the waste liquid in the flow path, and may be a pump 161 or another pressurizing unit (not shown).

[0065] If the PFAS concentration measured by the measuring sensor 403 is above a predetermined threshold, the control unit 10 sends the waste liquid through the polymer concentrator 11a towards the sulfuric acid treatment tank 12 and the detoxification device 14 (final treatment tank). If the PFAS concentration is below a predetermined threshold, the control unit 10 sends the waste liquid to the monomer concentrator 11b. Specifically, by controlling the valve 501 provided in the flow path 71, if the PFAS concentration measured by the measuring sensor 403 is above a predetermined threshold, the control unit 10 directs the waste liquid towards the flow path 73 to reach the polymer concentrator 11a. If the PFAS concentration is below a predetermined threshold, the control unit 10 directs the waste liquid towards the flow path 74 to reach the monomer concentrator 11b.

[0066] The control unit 10 may acquire measurement values ​​from each measurement sensor at each location, learn them including concentration changes and time lags, and output an alert if the concentration is higher than expected, indicating that the filter 39 may be deteriorating.

[0067] Next, the effects and benefits of the PFAS detoxification system 1 according to this embodiment will be explained.

[0068] The PFAS detoxification system 1 according to this embodiment comprises a flow path for waste liquid containing PFAS discharged from a semiconductor manufacturing apparatus 100, one or more measuring instruments 400 arranged on the flow path for measuring the concentration of PFAS contained in the waste liquid, and a control unit 10. The measuring instruments 400 measure the concentration of PFAS by measuring the pH or resistivity of the waste liquid, and the control unit 10 performs processing according to the concentration of PFAS measured by the measuring instruments 400.

[0069] With such a system, the concentration of PFAS in the flow path can be measured, and appropriate processing can be performed according to the concentration, such as issuing an alert if the concentration becomes too high. This allows for appropriate processing according to the concentration of PFAS in the wastewater of the semiconductor manufacturing apparatus 100.

[0070] The PFAS detoxification system 1 described above further comprises a filter 39 positioned in the flow path, and a storage tank 20x positioned downstream of the filter 39 in the flow path for storing waste liquid that has permeated through the filter 39. The measuring instrument 400 has a measuring sensor 402 provided in the storage tank 20x. In this way, by measuring the concentration of PFAS downstream of the filter 39, it is possible to appropriately perform processing such as outputting an alert when the concentration of PFAS downstream of the filter 39 is increasing, that is, when the collection capacity of the filter 39 is deteriorating. This makes it possible to appropriately replace the filter 39 before it deteriorates. In other words, if it is replaced as part of regular maintenance, depending on the usage conditions, the filter performance may have deteriorated significantly, or it may be replaced while it is still usable. In this regard, by estimating the deterioration of the collection capacity of the filter 39 from the concentration of PFAS downstream of the filter 39, it is possible to replace the filter at an appropriate time.

[0071] The measuring instrument 400 has a measuring sensor 401 positioned upstream of the filter 39 in the flow path. The control unit 10 may perform processing according to the concentration difference, which is the difference between the concentration of PFAS measured by the measuring sensor 401 and the concentration of PFAS measured by the measuring sensor 402. By considering the concentration difference before and after the filter 39 in this way, the deterioration of the collection capacity of the filter 39 can be appropriately detected, and if the collection capacity of the filter 39 has deteriorated, processing such as outputting an alert can be appropriately performed.

[0072] The PFAS detoxification system 1 further comprises a filter 40b located downstream of the storage tank 20x in the flow path, and a third storage tank 20y located downstream of the filter 40b in the flow path for storing waste liquid that has permeated through the filter 40b. The measuring instrument 400 may have a measuring sensor 404 provided in the third storage tank 20y. By measuring the concentration of PFAS in the filtrate of the third storage tank 20y, which is assumed to contain almost no PFAS, it is possible to appropriately determine whether the filtrate is in the expected condition and take action such as outputting an alert if it is not.

[0073] The control unit 10 may output an alert if the concentration of PFAS measured by the measurement sensor 402 is above a predetermined threshold. This allows the user to be appropriately informed of when it is time to replace the filter 39.

[0074] The control unit 10 may also control the pressurization section so that waste liquid flowing back into the filter 39 from the outlet side flows in when the above-mentioned concentration difference is greater than or equal to a predetermined threshold. This allows for the proper execution of a refresh process to clear clogging of the filter 39.

[0075] The control unit 10 may estimate the lifespan of the filter 39 according to the concentration of PFAS measured by the measuring sensor 402, identify a processing timing corresponding to the lifespan, and execute a predetermined process at that processing timing. With such a configuration, it is possible to output an alert or perform other actions at an appropriate timing calculated backward from the lifespan.

[0076] The control unit 10 may estimate the lifespan of the filter 39 according to the PFAS concentration measured by the measuring sensor 402 and the PFAS concentration measured by the measuring sensor 401, identify a processing timing corresponding to the lifespan, and execute a predetermined process at that processing timing. With such a configuration, it is possible to output an alert or perform other actions at an appropriate timing calculated backward from the lifespan.

[0077] The control unit 10 may also control the pressurization section so that the amount of waste liquid processed by the filter 39 decreases as the estimated lifespan of the filter 39 approaches its end. This reduces the amount of waste liquid processed by the filter 39 as its lifespan nears its end, thereby extending the life of the filter 39.

[0078] Generally, performing filtration slowly and gently improves decomposition efficiency, but it also reduces the processing capacity. Therefore, the pH and resistivity of the filtrate can be monitored, and if they are within acceptable limits, the pressure and flow rate can be increased.

[0079] The control unit 10 sends the waste liquid to the final treatment tank (sulfuric acid treatment tank 12, etc.) if the concentration of PFAS measured by the measuring sensor 403 is above a predetermined threshold. Alternatively, the control unit 10 may send the waste liquid to the monomer concentrator 11b if the concentration of PFAS measured by the measuring sensor 403 is below a predetermined threshold. With this configuration, processing with the filter 39, etc., is performed only when the concentration of PFAS is low, and if the concentration of PFAS becomes too high, it is possible to proceed to the final treatment, thereby enabling appropriate processing according to the concentration of PFAS. If the concentration of PFAS is above a predetermined threshold and is high, the efficiency of filtration deteriorates, so it is possible to treat it as waste liquid together with the polymer concentrate. This can suppress an increase in the amount of PFAS contained in the filtrate.

[0080] Finally, various exemplary embodiments included in this disclosure are described below in [E1] to [E23].

[0081] [E1] A processing system comprising: a flow path for waste liquid containing organofluorine compounds discharged from semiconductor manufacturing equipment; one or more measuring instruments disposed on the flow path for measuring the concentration of organofluorine compounds contained in the waste liquid; and a control unit, wherein the measuring instruments measure the concentration of the organofluorine compounds by measuring the pH or resistivity of the waste liquid; and the control unit performs processing according to the concentration of the organofluorine compounds measured by the measuring instruments.

[0082] [E2] The processing system according to [E1], further comprising: a first filter arranged in the flow path; and a first storage unit arranged downstream of the first filter in the flow path for storing the waste liquid that has passed through the first filter, wherein the measuring instrument has a first measuring sensor provided in the first storage unit.

[0083] [E3] The processing system according to [E2], wherein the measuring instrument has a second measuring sensor located upstream of the first filter in the flow path, and the control unit performs processing according to the concentration difference, which is the difference between the concentration of the organofluorine compound measured by the second measuring sensor and the concentration of the organofluorine compound measured by the first measuring sensor.

[0084] [E4] The processing system according to [E2] or [E3], further comprising: a second filter located downstream of the first storage section in the flow path; and a second storage section located downstream of the second filter in the flow path for storing the waste liquid that has passed through the second filter, wherein the measuring instrument has a third measuring sensor provided in the second storage section.

[0085] [E5] The processing system according to any one of [E2] to [E4], wherein the control unit outputs an alert when the concentration of the organofluorine compound measured by the first measuring sensor is above a predetermined threshold.

[0086] [E6] The processing system according to [E3], further comprising a pressurizing unit that pressurizes the waste liquid in the flow path to cause the waste liquid to flow back in the flow path, wherein the control unit controls the pressurizing unit so that the waste liquid that has flowed back from the outlet side flows into the first filter when the concentration difference is greater than or equal to a predetermined threshold.

[0087] [E7] The control unit estimates the lifespan of the first filter according to the concentration of the organofluorine compound measured by the first measuring sensor, identifies a processing timing corresponding to the lifespan, and executes a predetermined processing at the processing timing, according to any one of the items [E2] to [E6].

[0088] [E8] The measuring instrument has a second measuring sensor located upstream of the first filter in the flow path, and the control unit estimates the lifespan of the first filter according to the concentration of the organofluorine compound measured by the first measuring sensor and the concentration of the organofluorine compound measured by the second measuring sensor, identifies a processing timing corresponding to the lifespan, and executes a predetermined processing at the processing timing, according to any one of [E2] to [E7].

[0089] [E9] The processing system according to [E7] or [E8], further comprising a pressurizing unit for pressurizing the waste liquid in the flow path, wherein the control unit controls the pressurizing unit such that the amount of waste liquid processed by the first filter decreases as the estimated lifespan of the first filter approaches.

[0090] [E10] The treatment system according to any one of [E2] to [E9], further comprising: a final treatment tank for final treatment of the waste liquid; and a third storage unit located upstream of the first filter and storing the waste liquid sent toward the first filter, wherein the measuring instrument has a fourth measuring sensor located in the flow path in which the waste liquid containing the collected material collected by the first filter flows, and the control unit sends the waste liquid to the final treatment tank if the concentration of the organofluorine compound measured by the fourth measuring sensor is above a predetermined threshold, and sends the waste liquid to the third storage unit if the concentration of the organofluorine compound measured by the fourth measuring sensor is below a predetermined threshold.

[0091] [E11] A processing method comprising: a first step of measuring the concentration of an organofluorine compound contained in a waste liquid by measuring the pH or resistivity of the waste liquid using one or more measuring instruments placed on the flow path of the waste liquid containing an organofluorine compound discharged from a semiconductor manufacturing apparatus; and a second step of performing a treatment according to the concentration of the organofluorine compound measured by the measuring instruments in the first step.

[0092] [E12] The measuring instrument comprises a first measuring sensor located downstream of a first filter located in the flow path, and a second measuring sensor located upstream of the first filter in the flow path, wherein in the first step, the concentration of the organofluorine compound downstream of the first filter is measured by the first measuring sensor, and the concentration of the organofluorine compound upstream of the first filter is measured by the second measuring sensor, and in the second step, a process is performed according to the concentration difference, which is the difference between the concentration of the organofluorine compound measured by the second measuring sensor and the concentration of the organofluorine compound measured by the first measuring sensor. [E11] The processing method.

[0093] [E13] The processing method according to [E11] or [E12], wherein in the second step, an alert is output if the concentration of the organofluorine compound measured by the first measuring sensor is above a predetermined threshold.

[0094] [E14] The processing method according to [E12], wherein in the second step, when the concentration difference is greater than or equal to a predetermined threshold, the pressurizing unit that causes the waste liquid to flow back into the flow path is controlled by pressurizing the waste liquid in the flow path so that the waste liquid that has flowed back into the first filter from the outlet side flows in.

[0095] [E15] The processing method according to any one of [E12] to [E14], wherein in the second step, the lifespan of the first filter is estimated according to the concentration of the organofluorine compound measured by the first measuring sensor, a processing timing corresponding to the lifespan is identified, and a predetermined processing is performed at the processing timing.

[0096] [E16] The processing method according to any one of [E12] to [E15], wherein in the second step, the lifespan of the first filter is estimated according to the concentration of the organofluorine compound measured by the first measuring sensor and the concentration of the organofluorine compound measured by the second measuring sensor, a processing timing corresponding to the lifespan is identified, and a predetermined processing is performed at the processing timing.

[0097] [E17] The processing method according to [E15] or [E16], wherein in the second step, the pressurizing unit that pressurizes the waste liquid in the flow path is controlled such that the amount of waste liquid processed by the first filter decreases as the estimated lifespan of the first filter approaches.

[0098] [E18] The measuring instrument has a fourth measuring sensor positioned in the flow path in a portion into which the waste liquid containing the material collected by the first filter flows, and in the second step, if the concentration of the organofluorine compound measured by the fourth measuring sensor is above a predetermined threshold, the waste liquid is sent to a final treatment tank, and if the concentration of the organofluorine compound measured by the fourth measuring sensor is below a predetermined threshold, the waste liquid is sent to a third storage unit positioned upstream of the first filter and storing the waste liquid that is sent toward the first filter, according to any one of [E12] to [E17].

[0099] 1...PFAS detoxification system (processing system), 10...control unit, 11b...monomer concentrator (third storage unit), 39...filter (first filter), 40b...filter (second filter), 71, 72...flow channels, 100...semiconductor manufacturing equipment, 161...pump (pressurization unit), 400...measuring instrument, 401...measuring sensor (second measuring sensor), 402...measuring sensor (first measuring sensor), 403...measuring sensor (fourth measuring sensor), 404...measuring sensor (third measuring sensor).

Claims

1. A processing system comprising: a flow path for waste liquid containing organofluorine compounds discharged from semiconductor manufacturing equipment; one or more measuring instruments disposed on the flow path for measuring the concentration of organofluorine compounds contained in the waste liquid; and a control unit, wherein the measuring instruments measure the concentration of the organofluorine compounds by measuring the pH or resistivity of the waste liquid; and the control unit performs processing according to the concentration of the organofluorine compounds measured by the measuring instruments.

2. The processing system according to claim 1, further comprising: a first filter arranged in the flow path; and a first storage unit arranged downstream of the first filter in the flow path for storing the waste liquid that has passed through the first filter, wherein the measuring instrument has a first measuring sensor provided in the first storage unit.

3. The processing system according to claim 2, wherein the measuring instrument has a second measuring sensor located upstream of the first filter in the flow path, and the control unit performs processing according to the concentration difference, which is the difference between the concentration of the organofluorine compound measured by the second measuring sensor and the concentration of the organofluorine compound measured by the first measuring sensor.

4. The processing system according to claim 2, further comprising: a second filter located downstream of the first storage section in the flow path; and a second storage section located downstream of the second filter in the flow path for storing the waste liquid that has passed through the second filter, wherein the measuring instrument has a third measuring sensor provided in the second storage section.

5. The processing system according to claim 2, wherein the control unit outputs an alert when the concentration of the organofluorine compound measured by the first measuring sensor is above a predetermined threshold.

6. The processing system according to claim 3, further comprising a pressurizing unit that pressurizes the waste liquid in the flow path to cause the waste liquid to flow back in the flow path, wherein the control unit controls the pressurizing unit so that the waste liquid that has flowed back from the outlet side flows into the first filter when the concentration difference is greater than or equal to a predetermined threshold.

7. The processing system according to claim 2, wherein the control unit estimates the lifespan of the first filter according to the concentration of the organofluorine compound measured by the first measuring sensor, identifies a processing timing corresponding to the lifespan, and executes a predetermined processing at the processing timing.

8. The processing system according to claim 2, wherein the measuring instrument has a second measuring sensor positioned upstream of the first filter in the flow path, and the control unit estimates the lifespan of the first filter according to the concentration of the organofluorine compound measured by the first measuring sensor and the concentration of the organofluorine compound measured by the second measuring sensor, identifies a processing timing corresponding to the lifespan, and executes a predetermined processing at the processing timing.

9. The processing system according to claim 7 or 8, further comprising a pressurizing unit for pressurizing the waste liquid in the flow path, wherein the control unit controls the pressurizing unit such that the amount of waste liquid processed by the first filter decreases as the estimated lifespan of the first filter approaches.

10. The processing system according to claim 2, further comprising: a final processing tank for final processing of the waste liquid; and a third storage unit located upstream of the first filter and storing the waste liquid sent toward the first filter, wherein the measuring instrument has a fourth measuring sensor located in the flow path in the portion into which the waste liquid containing the collected material collected by the first filter flows; and the control unit sends the waste liquid to the final processing tank if the concentration of the organofluorine compound measured by the fourth measuring sensor is above a predetermined threshold, and sends the waste liquid to the third storage unit if the concentration of the organofluorine compound measured by the fourth measuring sensor is below a predetermined threshold.

11. A processing method comprising: a first step of measuring the concentration of an organofluorine compound contained in a waste liquid by measuring the pH or resistivity of the waste liquid using one or more measuring instruments placed on the flow path of the waste liquid containing an organofluorine compound discharged from a semiconductor manufacturing apparatus; and a second step of performing a treatment according to the concentration of the organofluorine compound measured by the measuring instruments in the first step.

12. The processing method according to claim 11, wherein the measuring instrument comprises a first measuring sensor located downstream of a first filter located in the flow path, and a second measuring sensor located upstream of the first filter in the flow path, wherein in the first step, the concentration of the organofluorine compound downstream of the first filter is measured by the first measuring sensor and the concentration of the organofluorine compound upstream of the first filter is measured by the second measuring sensor, and in the second step, processing is performed according to the concentration difference, which is the difference between the concentration of the organofluorine compound measured by the second measuring sensor and the concentration of the organofluorine compound measured by the first measuring sensor.

13. The processing method according to claim 12, wherein in the second step, an alert is output when the concentration of the organofluorine compound measured by the first measuring sensor is above a predetermined threshold.

14. The processing method according to claim 12, wherein in the second step, when the concentration difference is greater than or equal to a predetermined threshold, the pressurizing unit that causes the waste liquid to flow back into the flow path is controlled by pressurizing the waste liquid in the flow path so that the waste liquid that has flowed back into the first filter from the outlet side flows in.

15. The processing method according to claim 12, wherein in the second step, the lifespan of the first filter is estimated according to the concentration of the organofluorine compound measured by the first measuring sensor, a processing timing corresponding to the lifespan is identified, and a predetermined processing is performed at the processing timing.

16. The processing method according to claim 12, wherein in the second step, the lifespan of the first filter is estimated according to the concentration of the organofluorine compound measured by the first measuring sensor and the concentration of the organofluorine compound measured by the second measuring sensor, a processing timing corresponding to the lifespan is identified, and a predetermined processing is performed at the processing timing.

17. The processing method according to claim 15 or 16, wherein in the second step, the pressurizing unit that pressurizes the waste liquid in the flow path is controlled so that the amount of waste liquid processed by the first filter decreases as the estimated lifespan of the first filter approaches.

18. The processing method according to claim 12, wherein the measuring instrument has a fourth measuring sensor positioned in the flow path in a portion into which the waste liquid containing the material collected by the first filter flows, and in the second step, if the concentration of the organofluorine compound measured by the fourth measuring sensor is above a predetermined threshold, the waste liquid is sent to a final processing tank, and if the concentration of the organofluorine compound measured by the fourth measuring sensor is below a predetermined threshold, the waste liquid is sent to a third storage unit positioned upstream of the first filter and storing the waste liquid that is sent toward the first filter.

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