Processing system and processing method

Abstract

This processing system comprises: a developer concentration unit for concentrating a waste liquid containing a positive-type developer and discharged from a semiconductor manufacturing device; and a chemical solution processing unit for decomposing and volatilizing a first concentrated solution concentrated by the developer concentration unit.

Description

Processing system and processing method

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

[0002] Patent Document 1 describes a wastewater treatment system including a treatment device that reduces the content ratio of organic fluorine compounds and the like, an anion exchange building filled with ion exchangers including anion exchangers, and a decomposition device that decomposes the regenerated liquid that has circulated in the anion exchange building.

[0003] JP 2010-125352 A

[0004] The present disclosure provides a treatment system and a treatment method that can smoothly carry out detoxification treatment of organofluorine compounds.

[0005] A processing system according to one aspect of the present disclosure includes a developer concentrating section that concentrates waste liquid containing a positive developer discharged from a semiconductor manufacturing device, and a chemical processing section that decomposes and volatilizes the first concentrated liquid concentrated by the developer concentrating section.

[0006] According to the present disclosure, detoxification treatment of organic fluorine compounds can be smoothly carried out.

[0007] FIG. 1 is a schematic diagram of a PFAS detoxification system according to the present embodiment. FIG. 2 is a configuration diagram of the PFAS detoxification system shown in FIG. 1. FIG. 3 is a diagram explaining the filtration of a liquid containing PFAS. FIG. 4 is a diagram explaining the cleaning of a filter by backflowing filtrate. FIG. 5 is a diagram explaining the separation of gas. FIG. 6 is a diagram explaining the function of a gas filter. FIG. 7 is a diagram explaining the separation of taken-in outside air. FIG. 8 is a diagram explaining the concentration and decomposition of a positive developer. FIG. 9 is a diagram explaining the cleaning of a filter by backflowing filtrate. FIG. 10 is a diagram explaining the discharge of SPM waste liquid. FIG. 11 is a diagram explaining the cleaning of a filter with SPM waste liquid. FIG. 12 is a diagram explaining a decomposition treatment chamber according to a modified example. FIG. 13 is a diagram explaining a return line according to a modified example.

[0008] Hereinafter, the embodiments will be described in detail with reference to the drawings. In the description, the same elements or elements having the same functions are denoted by the same reference numerals, and redundant description will be omitted.

[0009] As shown in Fig. 1, the processing system according to this embodiment is a PFAS detoxification system 1 that detoxifies PFAS discharged from a semiconductor manufacturing apparatus 100. Note that Fig. 1 shows an outline of the configuration of the PFAS detoxification system 1, and some components (for example, components related to TMAH (tetramethylammonium hydroxide) waste liquid, which will be described later) are not shown. PFAS refers to per- and polyfluoroalkyl substances (PFAS), which are organic fluorine compounds.

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

[0011] PFAS is stable in nature and difficult to decompose. Therefore, PFAS has a high persistence and a tendency to accumulate in living organisms, and is said to be highly harmful. The PFAS detoxification system 1 according to this embodiment is a system that detoxifies PFAS discharged from a semiconductor manufacturing apparatus 100, thereby preventing the discharge of PFAS to the outside.

[0012] As shown in FIG. 1 , the PFAS detoxification system 1 includes a concentrator 11 (concentration section, waste liquid storage section), a sulfuric acid treatment tank 12 (chemical treatment section, decomposition treatment section), a cooler 13 (collection section), and a detoxification device 14 (combustion detoxification device). While the present embodiment describes the PFAS detoxification system 1 as a group of devices, the PFAS detoxification system 1 may also be configured as a single device. The semiconductor manufacturing apparatus 100 includes 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 substances containing PFAS as it performs processing. The processing sections of the PFAS detoxification system 1 may or may not be installed in the same space (location). For example, each processing unit may be installed inside the building where the lithography apparatus 111, cleaning apparatus 112, or etching apparatus 113 is installed, or may be installed outside the building or in an adjacent space. Each processing unit may be installed separately inside and outside the building. Furthermore, among the concentrator 11, sulfuric acid treatment tank 12, cooler 13, and detoxification apparatus 14, those that are not in use do not need to be installed all the time.

[0013] The lithography apparatus 111 includes a coating / developing apparatus and an exposure apparatus. The exposure apparatus performs an exposure process on a resist film. Specifically, it irradiates an exposure target portion of a resist film (photosensitive coating) with energy rays using a method such as immersion exposure. The coating / developing apparatus forms a resist film on the surface of a substrate before the exposure process using the exposure apparatus, and then develops the resist film after the exposure process. PFAS is contained in liquids or gases discharged from the lithography apparatus 111. For example, PFAS is contained in resist waste liquid, alkaline waste liquid (positive developer) from the development process, acid waste liquid from resist stripping, organic exhaust, thermal exhaust, solidified sublimate, etc. In addition, organic solvent waste liquid from negative development process can also be considered extremely diluted resist waste liquid, and contains PFAS. In this embodiment, PFAS may be treated the same as the resist waste liquid described above. In this embodiment, PFAS contained in resist waste liquid and PFAS contained in positive developer will be mainly described. Examples of PFAS contained in the resist waste liquid include a photo acid generator (PAG), a surfactant, or a polymer modified with F. The resist waste liquid discharged from the lithography apparatus 111 is introduced into the concentrator 11 of the PFAS detoxification system 1.

[0014] The cleaning device 112 performs a cleaning process on the substrate. For example, the cleaning device 112 uses H ２ O ２ The cleaning device 112 uses SPM (Sulfuric Acid Hydrogen Peroxide Mixture), which is a mixture of sulfuric acid and sulfuric acid. ２ O ２ A mixed aqueous solution of HCl and H O (SC2: Standard Clean 2) was used to remove particles. ２ O ２A mixed aqueous solution (SC1) of sulfuric acid and ammonia is used. Hot concentrated sulfuric acid alone is also produced during the waste liquid treatment. The cleaning device 112 discharges SPM waste liquid containing PFAS. The SPM waste liquid 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 acid waste gas containing PFAS. The acid waste gas discharged from the cleaning device 112 is introduced into the detoxification device 14.

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

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

[0017] The concentrator 11 concentrates the resist waste liquid containing PFAS discharged from the lithography tool 111 of the semiconductor manufacturing equipment 100. That is, the concentrator 11 concentrates the substrate processing waste liquid in the lithography tool 111 as waste liquid containing PFAS. The concentrator 11 concentrates the resist waste liquid and separates the solvent contained in the resist waste liquid using, for example, an ultrafiltration membrane or a reverse osmosis membrane (details will be described later). The concentrated resist waste liquid is a concentrated liquid containing a polymer, and therefore has a high viscosity. The concentrated resist waste liquid is introduced into the sulfuric acid treatment tank 12. Note that when the alkaline waste liquid discharged from the lithography tool 111 is concentrated by the concentrator 11, the alkaline waste liquid may be introduced into the reverse osmosis membrane after being neutralized.

[0018] The solvent separated from the resist waste liquid may be used as a recycled solvent for cup cleaning in the semiconductor manufacturing equipment 100, or may be collected by a solvent recovery company. In conventional cases, when solvent recovery companies attempt to refine recycled solvent from resist waste liquid by analyzing its components, there is a possibility that they may also recover waste liquid containing confidential materials of the resist manufacturer. In this regard, in the resist waste liquid passed through the concentrator 11 as in this embodiment, the solid components are contained in the concentrated liquid, thereby preventing confidential information from being leaked to the solvent recovery company.

[0019] The sulfuric acid treatment tank 12 decomposes and volatilizes the concentrated liquid concentrated by the concentrator 11 with the SPM waste liquid. That is, the sulfuric acid treatment tank 12 utilizes the SPM waste liquid from the cleaning device 112. In the SPM waste liquid, decomposition reactions such as oxidation and dehydration occur in the solvent and polymer, resulting in lower molecular weights (lower viscosity). At this time, the temperature of the SPM waste liquid increases due to an exothermic reaction (the temperature of the hot concentrated sulfuric acid in the SPM waste liquid increases). PFAS is not basically decomposed, but components such as PAG have low boiling points and are volatilized by the high-temperature SPM waste liquid (particularly due to the effect of the hot concentrated sulfuric acid contained in the SPM waste liquid). Conventionally, SPM waste liquid has been treated by adding catalase to prevent foaming, but in the sulfuric acid treatment tank 12, the SPM waste liquid is reacted with organic matter to produce H2O. ２ O ２ If all of these components are used up and degassed, downstream sulfuric acid waste liquid will not foam, making it easier to treat. It also reduces catalase levels. Because this reaction generates heat, for example, around 300°C, temperature difference power generation using the exhaust heat or steam generated from the circulating water used to cool the sulfuric acid treatment tank 12 may be used for power generation. The sulfuric acid waste liquid discharged from the sulfuric acid treatment tank 12 is recovered, for example, by a recycling company. This sulfuric acid waste liquid has a higher sulfuric acid purity than conventional waste liquids. It is desirable to treat the sulfuric acid treatment tank 12 in an inert nitrogen atmosphere to prevent accidental ignition. The SPM waste liquid may also be hot concentrated sulfuric acid waste liquid. In the case of hot concentrated sulfuric acid, decomposition reactions occur in the solvent and polymer, resulting in lower differentiation (lower viscosity). At this time, the temperature of the hot concentrated sulfuric acid increases due to an exothermic reaction, volatilizing PFAS, PAG, and the like.

[0020] When the concentrated resist waste solution is added to the SPM waste solution stored in the sulfuric acid treatment tank 12 and treated, H ２ O ２ As a result, the sulfuric acid treatment tank 12 is consumed, reducing the treatment capacity. After an appropriate amount of concentrated resist waste liquid is supplied, the sulfuric acid treatment tank 12 is placed on standby until the reaction settles down and gas generation ceases. Because a large amount of SPM waste liquid is produced from the cleaning device 112, it is necessary to treat the SPM waste liquid from the cleaning device 112 without delay. Therefore, the sulfuric acid treatment tank 12 may be composed of multiple treatment tanks. In this case, while one treatment tank is being treated, preparations such as the injection of liquid may be made in other treatment tanks. Furthermore, the liquid may be flowed downstream, such as through the first treatment tank, then the second treatment tank, and then the third treatment tank, depending on the progress of the reaction. If the resist waste liquid is a metal-containing resist, only the metal components precipitate without volatilization and are treated together with the sulfuric acid waste liquid in the same processes as those described above.

[0021] Since SPM waste liquid contains hydrogen peroxide, if it is disposed of as waste liquid, it may foam, putting a strain on the equipment, or the foaming gas may cause environmental damage. In this regard, the configuration according to this embodiment effectively utilizes the remaining hydrogen peroxide, and the foaming gas is also burned as fuel in the detoxification device 14, thereby reducing the burden on the equipment and the environment.

[0022] The cooler 13 liquefies and collects the PFAS-containing gas volatilized by the sulfuric acid treatment tank 12. The cooler 13 separates and collects the gas into a gaseous component, a low-molecular-weight gas, and a liquid component, a hydrocarbon (HC) extract. As shown in FIG. 2 , the gas from the sulfuric acid treatment tank 12 is cooled in the cooler 13, and the liquefied gas is collected as a HC (hydrocarbon) extract, while the non-condensed low-molecular-weight gas is also collected. The gas generated from the sulfuric acid treatment tank 12 is treated in a nitrogen atmosphere, and therefore is a mixed gas containing nitrogen. Since a mixed gas containing a large amount of nitrogen requires a large amount of processing in the subsequent detoxification device 14, the non-condensed low-molecular-weight gas in the cooler 13 may be separated into nitrogen and other components and concentrated using, for example, a nano-sub-ceramic filter.

[0023] A variety of organic gases and other gases are discharged from the sulfuric acid treatment tank 12 described above. PFAS such as PAG are also discharged as gases. While it is possible to directly introduce these gases into the detoxification device 14, transportability can be improved by first liquefying gases that become liquid at room temperature in the cooler 13. If the gases are transported without liquefaction, liquid pools may form in the piping, making control difficult. PFAS are contained in both the liquefied HC extract and the uncondensed low-molecular-weight gas. The HC extract and the 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 substances treated by the cooler 13. The detoxification device 14 may be a combustion detoxification device that detoxifies the substances treated by the cooler 13 by combustion. The detoxification device 14 incinerates the HC extract and low-molecular-weight gases introduced from the cooler 13. Most of the HC extract is hydrocarbon, so it can be burned as fuel. Most of the low-molecular-weight gases are hydrocarbons with a carbon number of 10 or less, so they can also be burned as fuel. Conventionally, propane gas or city gas has been used as fuel in combustion detoxification devices, but since the HC extract, etc. is used as fuel as described above, the amount of propane gas, etc. can be reduced.

[0025] Furthermore, the detoxification device 14 may simultaneously combust and detoxify the exhaust gas introduced from the etching device 113, the exhaust gas introduced from the film-forming device 114, and the acid waste gas introduced from the cleaning device 112. These gases contain PFAS used in each device. By simultaneously combusting and detoxifying these gases, the amount of propane gas and other gases can be further reduced. During the combustion and detoxification, electricity may be generated by burning them using an internal combustion engine such as a gas turbine. Detoxified gases such as carbon dioxide may be recovered and used to synthesize organic substances such as formic acid and methanol. The detoxification device 14 may also be a subcritical treatment device that performs subcritical treatment on the material treated by the cooler 13, or a supercritical treatment device that performs supercritical treatment. The detoxified waste gas may also be processed into fluorine-ion-containing scrubber water and waste gas through a scrubber device (a device that washes the waste gas with water, neutralizes it with chemicals, or adsorbs it and releases it into the atmosphere). The scrubber water can be converted into calcium fluoride or fluorite by reacting it with calcium. Fluorite is the starting material for fluorine compounds, making it a resource that can be recycled.

[0026] Next, details of the PFAS detoxification system 1 shown in FIG. 1 will be described with reference to FIGS. 2 to 11. FIG. 2 is a configuration diagram of the PFAS detoxification system 1 shown in FIG. 1. FIG. 2 also illustrates components (such as components related to the TMAH waste liquid) that are omitted from FIG. 1. The PFAS detoxification system 1 further includes a waste liquid supply path 15 (second supply path), a circulation path 16 (first path), a first filtrate path 17 (second path), a second filtrate path 18 (fourth path), a third filtrate path 19 (third path), a first reservoir 20x, and a second reservoir 20y. The PFAS detoxification system 1 further includes a bypass path 21. The PFAS detoxification system 1 further includes a first gas filter 22, a vacuum pump 23, and a distiller 24. The PFAS detoxification system 1 further includes a second gas filter 25. The PFAS detoxification system 1 further includes a waste liquid supply path 26 (first supply path), a concentrator 27 (developer concentrating section), a circulation path 28, a developer path 29, a recycled developer storage section 30, a developer treatment tank 31 (chemical treatment section), a third gas filter 32, and a generator 33. The PFAS detoxification system 1 further includes a bypass path 34, a backflow liquid storage section 35, and a recovery path 36. The PFAS detoxification system 1 further includes a discharge path 37. The PFAS detoxification system 1 further includes an SPM supply path 38.

[0027] FIG. 3 is a diagram illustrating the filtration of resist waste liquid, which is a liquid containing PFAS. As described above, the concentrator 11 concentrates the resist waste liquid containing PFAS discharged from the lithography apparatus 111. The circulation flow path 16 is a circulation flow path connected to the concentrator 11, and a filter 39 (first filter) for removing polymers is provided midway along the flow path. The filter 39 is, for example, a hollow fiber filter. The provision of the filter 39 concentrates the resist waste liquid. The filtrate (solvent) that passes through the filter 39 flows through the first filtrate flow path 17 and is stored in the first reservoir 20x (filtrate reservoir). This filtrate is a low-concentration PFAS solution. The first reservoir 20x is connected to the first filtrate flow path 17 and serves as a reservoir for storing the filtrate. The second filtrate flow path 18 (filtrate reservoir) is a flow path connecting the first reservoir 20x and the second reservoir 20y. A filter 40 (second filter) is provided in the second filtrate flow path 18. The filter 40 is, for example, an ion exchange resin filter. By providing the filter 40, the filtrate that has passed through the filter 40 can be made into a solution that does not contain PFAS. The filtrate that has passed through the filter 40 flows through the second filtrate flow path 18 and is stored in the second reservoir 20y. This filtrate can be used as a regenerated solvent and flows to the outside from the third filtrate flow path 19 downstream of the second reservoir 20y.

[0028] FIG. 4 illustrates cleaning of the filter 39 by backflowing the filtrate. It is conceivable that the filter 39 may become clogged with polymer components and the like over time. To eliminate such clogging, the filtrate flowing through the third filtrate flow path 19 may be introduced into the outlet side of the filter 39. That is, a bypass flow path 21 may be provided to connect the third filtrate flow path 19 and the first filtrate flow path 17. The filtrate in the bypass flow path 21 may be pressurized to cause the filtrate to flow back through the first filtrate flow path 17 and then flow into the circulation flow path 16 from the outlet side of the filter 39. Such liquid pressurization may be achieved, for example, by gas pressure or by a liquid delivery unit such as a pump. By using the filtrate to flow back through the filter 39, the filter 39 can be unclogged and refreshed. The filtrate to be backflowed may be the filtrate flowing through the second filtrate flow path 18.

[0029] FIG. 5 is a diagram illustrating gas separation. As described above, the concentrated liquid concentrated by the concentrator 11 is decomposed and volatilized by the SPM waste liquid in the sulfuric acid treatment tank 12. This causes decomposition reactions such as oxidation and dehydration, resulting in decomposition into gases containing carbon monoxide, carbon dioxide, nitrogen, water vapor, hydrocarbon gases, and PFAS. The gas released in this process reaches a temperature of 100°C or higher. The gas volatilized in the sulfuric acid treatment tank 12 is then separated by the first gas filter 22. The first gas filter 22 is a filter that separates the gas volatilized in the sulfuric acid treatment tank 12 into a PFAS-rich gas and a PFAS-removed gas. The first gas filter 22 is, for example, a pervaporation filter, but may also be a ceramic filter. The first gas filter 22 is heated to a temperature higher than that of the concentrated liquid before decomposition due to heat generated in the sulfuric acid treatment tank 12. The first gas filter 22 may be disposed in the same space as the sulfuric acid treatment tank 12, or may be connected to the sulfuric acid treatment tank 12 by a conductive member such as metal, thereby receiving heat generated in the sulfuric acid treatment tank 12. In this embodiment, the PFAS-rich gas refers to a gas in which the PFAS concentration is higher than that of the gas before it is affected by the predetermined action. In the explanation based on FIG. 5 above, 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. When PFAS-rich gas is generated, the action that causes it to be generated can be considered to be the predetermined action.

[0030] 6 is a diagram illustrating the function of the first gas filter 22 when a pervaporation filter is used as the first gas filter 22. As shown in FIG. 6, the first gas filter 22, which is a pervaporation filter, is a filter that separates gases by utilizing differences in momentum due to differences in molecular weight. That is, the first gas filter 22 allows gases with relatively small molecular weights (nitrogen, carbon monoxide, carbon dioxide, water vapor, etc.) to pass (flow downstream) while blocking gases with relatively large molecular weights (PFAS, hydrocarbons) by, for example, reducing the pressure downstream. This allows for the PFAS-rich gas to be largely separated from the PFAS-removed gas.

[0031] Returning to Figure 5, the vacuum pump 23 is a pump that reduces the pressure downstream of the first gas filter 22 and achieves the separation of gases by the first gas filter 22 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, described below) are introduced from the distiller 24 into the detoxification device 14.

[0032] FIG. 7 is a diagram illustrating the separation of taken-in outside air. As shown in FIG. 7, the PFAS detoxification system 1 takes in outside air and separates it into nitrogen and oxygen using the second gas filter 25. That is, the second gas filter 25 separates the outside air into a first diverted gas (hereinafter simply referred to as nitrogen) having a higher nitrogen concentration than air, and a second diverted gas (hereinafter simply referred to as oxygen) having a higher oxygen concentration than air. The second gas filter 25 then supplies the nitrogen to the sulfuric acid treatment tank 12. This prevents 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. Note that the detoxification device 14 may be supplied with ozone generated from the oxygen described above. Such ozone may be supplied to the distiller 24 and then introduced into the detoxification device 14, or 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.

[0033] 8 is a diagram illustrating the concentration and decomposition of a positive developer. As shown in FIG. 8, in the PFAS detoxification system 1, a TMAH waste liquid, which is a positive developer, is introduced from, for example, a lithography apparatus 111. 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 a concentrator 27. Furthermore, a first concentrated liquid, which is a concentrated liquid of the positive developer concentrated by the concentrator 27, is decomposed and volatilized in a developer treatment tank 31.

[0034] The waste liquid supply path 26 is a supply path that supplies the TMAH waste liquid introduced from the lithography apparatus 111 to the concentrator 27. The waste liquid supply path 26 and the waste liquid supply path 15 that supplies the resist waste liquid to the concentrator 11 are provided separately. The waste liquid supply path 26 is provided with a filter 41 that removes polymers. The circulation flow path 28 is a circulation flow path connected to the concentrator 27, and is provided with a filter 42 in the middle of the flow path for increasing the concentration of PFAS. The developer that has passed through the filter 42 (PFAS-free developer) passes through the developer flow path 29 and is stored in the recycled developer storage section 30. Such a developer can be used as recycled developer.

[0035] The concentrated solution (developer with a high PFAS concentration) concentrated 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 provided in contact with the sulfuric acid treatment tank 12 (a decomposition treatment unit for the second concentrated solution, which has a higher resist concentration than the first concentrated solution, which is a concentrated solution of a positive developer). Specifically, the developer treatment tank 31 is provided so as to surround the sulfuric acid treatment tank 12 from below. This allows the developer treatment tank 31 to receive heat from the sulfuric acid treatment tank 12, which can decompose and volatilize the first concentrated solution. Note that the method for decomposing the first concentrated solution is not limited to heat; for example, the first concentrated solution may be decomposed by exposure to microorganisms. The first concentrated solution may also be used as a cooling solvent for the SPM in the sulfuric acid treatment tank 12.

[0036] TMAH decomposed by heat (e.g., at approximately 140°C) in the developer treatment tank 31 is decomposed into trimethylamine and dimethyl ether. These gases can be used as fuel in the detoxification device 14. PFAS is not decomposed by heat but is released as a gas and burned in the detoxification device 14. The gas released from the developer treatment tank 31 contains nitrogen, water vapor, hydrocarbons, trimethylamine, dimethyl ether, PFAS, and the like. The third gas filter 32, for example, reduces the pressure downstream to allow gases with relatively small molecular weights (nitrogen, water vapor, etc.) to pass (flow downstream) while blocking gases with relatively large molecular weights (trimethylamine, dimethyl ether, PFAS, hydrocarbons). This allows for the PFAS-rich gas to be largely separated from the PFAS-removed gas. Nitrogen, water vapor, and the like are released outside the system. The released water vapor is converted back into water in the generator 33, allowing power generation using the pressure difference. The gas containing PFAS and the like sent to the detoxification device 14 may be compressed before being sent to the detoxification device 14 .

[0037] The detoxification device 14 may have a combustion chamber that mixes and burns gas related to the first concentrated liquid vaporized by the developer treatment tank 31 and gas related to the second concentrated liquid vaporized by the sulfuric acid treatment tank 12.

[0038] FIG. 9 is a diagram illustrating cleaning of the filter 41 by backflowing the filtrate. It is conceivable that the filter 41 may become clogged with polymer components and the like over time. To eliminate such clogging, the filtrate flowing through the third filtrate flow path 19 may be introduced into the outlet side of the filter 41. Specifically, a bypass flow path 34 is provided, which is connected to the bypass flow path 21 connected to the third filtrate flow path 19 and is also connected to the waste liquid supply path 26 downstream of the filter 41. The filtrate in the bypass flow path 34 may be pressurized to cause the filtrate to flow back in the waste liquid supply path 26 and to flow into the outlet side of the filter 41. Such liquid pressurization may be performed, for example, by gas pressure or by a liquid delivery unit such as a pump. By using the filtrate to backflow the filter 41, the filter 41 can be unclogged and refreshed. The backflowing filtrate may be the filtrate flowing through the second filtrate flow path 18. Because polymer removal by the filter 41 is not possible during such filter cleaning, the filters 41 may be arranged in parallel (multiple filters 41).

[0039] When filtrate flows into the filter 41 from the outlet side, the backflow liquid flowing out from the inlet side of the filter 41 is stored in the backflow liquid storage section 35. The backflow liquid storage section 35 is connected to the concentrator 11 by a recovery flow path 36. The recovery flow path 36 is a flow path that sends the backflow liquid from the backflow liquid storage section 35 to the concentrator 11. By providing this recovery flow path 36, the liquid that has been caused to flow back to unclog the filter 41 can be recovered from the backflow liquid storage section 35 to the concentrator 11.

[0040] FIG. 10 is a diagram illustrating the discharge of SPM waste liquid. As the reaction between the resist concentrate and the SPM waste liquid progresses in the sulfuric acid treatment tank 12, the hydrogen peroxide in the SPM is deactivated, significantly reducing its reactivity. At this time, the SPM becomes concentrated sulfuric acid, which can cause a dehydration reaction, but carbonization of organic matter progresses, causing the liquid to turn yellow or brown. Therefore, for example, when the liquid turns yellow, the SPM waste liquid is discharged through the discharge flow path 37. At this time, carbonized matter is filtered out by a filter 43 provided in the discharge flow path 37. The discharged SPM waste liquid is free of hydrogen peroxide and the purity of the sulfuric acid has been increased by filtering through the filter 43, so it can be used as recycled sulfuric acid.

[0041] 11 is a diagram illustrating the cleaning of the filter 43 with the SPM waste liquid. When new SPM waste liquid is supplied to the sulfuric acid treatment tank 12, a portion of the SPM waste liquid can be introduced into the outlet side of the filter 43 to clean the filter 43 that traps the carbonized matter. That is, the SPM waste liquid may be caused to react with the carbonized matter trapped in the filter 43 by flowing the SPM waste liquid into a flow path connected to the outlet of the filter 43 within the SPM supply path 38 for supplying new SPM waste liquid to the sulfuric acid treatment tank 12. As a result, the carbonized matter trapped in the filter 43 is converted into carbon dioxide, which is discharged, and the filter 43 is cleaned.

[0042] Next, the effects of the PFAS detoxification system 1 according to this embodiment will be described.

[0043] The PFAS detoxification system 1 according to this embodiment includes a concentrator 11 that concentrates PFAS-containing resist wastewater discharged from a lithography tool 111 in a semiconductor manufacturing apparatus 100. The PFAS detoxification system 1 also includes a sulfuric acid treatment tank 12 that decomposes and volatilizes the concentrated liquid concentrated by the concentrator 11. In the PFAS detoxification system 1 according to this embodiment, after the PFAS-containing wastewater is concentrated, the concentrated liquid is decomposed and volatilized. As a result, polymers, solvents, and the like are decomposed into lower molecular weight compounds by decomposition reactions in dehydration reactions, and PFAS is volatilized. The PFAS detoxification system 1 described above allows for smooth detoxification of PFAS.

[0044] The sulfuric acid treatment tank 12 may decompose and volatilize the concentrated liquid using a liquid containing hot concentrated sulfuric acid. In this way, by mixing the concentrated liquid with the liquid containing hot concentrated sulfuric acid, the polymer, solvent, etc. are decomposed into smaller molecules through a dehydration reaction, and PFAS is volatilized. By degassing the mixed liquid through an organic reaction, the liquid is less likely to foam in subsequent treatments, making the subsequent treatments easier.

[0045] The PFAS detoxification system 1 further includes a circulation flow path 16 connected to the concentrator 11 and having a filter 39 installed therein, and a first filtrate flow path 17 through which the filtrate of the concentrated liquid that has passed through the filter flows. The PFAS detoxification system 1 also includes a first reservoir 20x connected to the first filtrate flow path 17 and for storing the filtrate. With this configuration, the waste liquid can be appropriately concentrated using the filter 39, and the filtrate that has passed through the filter 39 can be stored and used, for example, as a regenerated solvent.

[0046] The PFAS detoxification system 1 further includes a third filtrate flow path 19 downstream of the second reservoir 20y, and a bypass flow path 21 connecting the third filtrate flow path 19 and the first filtrate flow path 17. In the PFAS detoxification system 1, pressurization of the liquid in the bypass flow path 21 causes the liquid to flow backward in the first filtrate flow path 17 and into the circulation flow path 16 from the outlet side of the filter 39. By thus allowing the filtrate to flow from the outlet side of the filter 39 via the bypass flow path 21, clogging of the filter 39 can be eliminated and the filter 39 can be properly cleaned.

[0047] The PFAS detoxification system 1 further includes a second filtrate flow path 18 provided with a filter 40, and the second filtrate flow path 18 connects the first reservoir 20x and the second reservoir 10y. In this way, two reservoirs are provided as filtrate reservoirs, and the filter 40 is provided between them, so that the filtrate with a reduced PFAS concentration can be appropriately extracted and stored.

[0048] The PFAS detoxification system 1 may further include a first gas filter 22 that separates the gas volatilized by the sulfuric acid treatment tank 12 into a PFAS-rich gas and a PFAS-removed gas. By providing such a first gas filter 22, the PFAS-rich gas and the PFAS-removed gas can be appropriately separated.

[0049] The first gas filter 22 may be heated to a temperature higher than that of the concentrated liquid by receiving heat generated in the sulfuric acid treatment tank 12. By heating the first gas filter 22 to a high temperature in this manner, the PFAS to be separated passes through the first gas filter 22 less easily than other gases, and therefore, gas separation can be performed appropriately by utilizing the difference in flow rate change due to heating.

[0050] The PFAS detoxification system 1 further includes a second gas filter 25 that takes in outside air and separates the outside air into a first diverted gas having a higher nitrogen concentration than air and a second diverted gas having a higher oxygen concentration than air. The second gas filter 25 may supply the first diverted gas to the sulfuric acid treatment tank 12. By supplying gas with a high nitrogen concentration to the sulfuric acid treatment tank 12 in this manner, it is possible to prevent fire in the sulfuric acid treatment tank 12.

[0051] The PFAS detoxification system 1 further includes a detoxification device 14 that combusts and detoxifies PFAS contained in the gas volatilized by the sulfuric acid treatment tank 12, and the second gas filter 25 may supply the second diverted gas to the detoxification device 14. In this way, supplying gas with a high oxygen concentration to the detoxification device 14 can promote combustion in the detoxification device 14.

[0052] The PFAS detoxification system 1 further includes a concentrator 27 that concentrates waste liquid containing a positive developer discharged from the lithography apparatus 111 of the semiconductor manufacturing apparatus 100, and a developer treatment tank 31 that decomposes and volatilizes the first concentrated liquid concentrated by the concentrator 27. In the PFAS detoxification system 1 according to this embodiment, after the waste liquid containing a positive developer, which is waste liquid containing PFAS, is concentrated, the concentrated liquid is decomposed and volatilized. As a result, polymers, solvents, etc. are decomposed into lower molecular weight compounds by decomposition reactions of dehydration reactions, and PFAS is volatilized. Such a PFAS detoxification system 1 allows for smooth detoxification of PFAS.

[0053] The PFAS detoxification system 1 further includes a waste liquid supply path 26 that supplies waste liquid containing a positive developer to a concentrator 27, and a waste liquid supply path 15 that supplies waste liquid having a higher resist concentration than the waste liquid containing the positive developer to a sulfuric acid treatment tank 12, which is a decomposition treatment section corresponding to the waste liquid. The waste liquid supply path 26 and the waste liquid supply path 15 are provided separately. By providing the supply path for the waste liquid containing the positive developer (waste liquid supply path 26) and the supply path for the waste liquid with a high resist concentration (waste liquid supply path 15) separately, it is possible to suppress the generation of excess salts due to, for example, an acid-alkali reaction.

[0054] The first concentrated liquid may be decomposed and volatilized by heat in the developer treatment tank 31. In this way, the first concentrated liquid is decomposed or the like by heat, so that the first concentrated liquid can be decomposed appropriately.

[0055] The developer treatment tank 31 may be provided in contact with the sulfuric acid treatment tank 12, which is a decomposition treatment unit for a second concentrated liquid having a higher resist concentration than the first concentrated liquid. With this configuration, the first concentrated liquid can be appropriately separated by utilizing the heat of reaction in the sulfuric acid treatment tank 12, which is a decomposition treatment unit for the second concentrated liquid. Furthermore, since the developer treatment tank 31 is in contact with the sulfuric acid treatment tank 12, the container of the sulfuric acid treatment tank 12 (and therefore the SPM waste liquid) can be cooled.

[0056] The PFAS detoxification system 1 further includes a detoxification device 14 that combusts and detoxifies PFAS. The detoxification device 14 has a combustion chamber that mixes and burns gas associated with the first concentrated liquid volatilized by the developer treatment tank 31 and gas associated with the second concentrated liquid volatilized by the sulfuric acid treatment tank 12. In this way, the gas associated with the first concentrated liquid decomposed and volatilized by the developer treatment tank 31 and the gas associated with the second concentrated liquid decomposed and volatilized by the sulfuric acid treatment tank 12 are used for combustion in the combustion chamber. This reduces the amount of fuel introduced into the detoxification device 14, suppresses overall CO2 emissions, and avoids the need for larger incineration facilities.

[0057] The PFAS detoxification system 1 may pressurize the filtrate in the bypass flow path 34 to cause the liquid to flow backward in the waste liquid supply path 26 and cause the filtrate to flow into the filter 41 from the outlet side. By causing the filtrate to flow into the filter 41 from the outlet side via the bypass flow path 34 in this way, clogging of the filter 41 can be eliminated and the filter 41 can be properly cleaned.

[0058] The PFAS detoxification system 1 includes a backflow liquid storage section 35 that stores backflow liquid flowing out from the inlet side of the filter 41 when filtrate flows in from the outlet side of the filter 41. The system may further include a recovery flow path 36 that connects the backflow liquid storage section 35 to the concentrator 11 and sends the backflow liquid from the backflow liquid storage section 35 to the concentrator 11. This allows the liquid that has been backflowed to clean the filter 41 to be properly recovered.

[0059] Although the present embodiment has been described above, the present disclosure is not limited to the above. For example, although the description has been given assuming that the chemical treatment unit for waste liquid containing a positive developer is provided in contact with the sulfuric acid treatment tank 12, which is a chemical treatment unit for resist waste liquid, the present disclosure is not limited to this. For example, as shown in FIG. 12 , the decomposition treatment chamber 135, which is a chemical treatment unit for waste liquid containing a positive developer, may be provided separately from the sulfuric acid treatment tank 12. In this case, the sulfuric acid treatment tank 12 may be cooled by a refrigerant tank 131 containing a refrigerant.

[0060] 13, a flow path 150 may be provided to connect the concentrator 27 and the developer treatment tank 31, and a heat exchanger 151 may be provided in the flow path 150. In this case, the first concentrated solution in the developer treatment tank 31 can be returned to the concentrator 27 side via the flow path 150.

[0061] Finally, various exemplary embodiments included in the present disclosure are described below in [E1] to [E23].

[0062] [E1] The processing system includes a concentrating section that concentrates waste liquid containing an organic fluorine compound discharged from a semiconductor manufacturing device, and a chemical processing section that decomposes and volatilizes the concentrated liquid concentrated by the concentrating section.

[0063] [E2] The processing system according to [E1], wherein the chemical processing unit decomposes and volatilizes the concentrated liquid with a liquid containing hot concentrated sulfuric acid.

[0064] [E3] The treatment system according to [E1] or [E2], further comprising: a first flow path connected to the concentration unit and having a first filter provided therein; a second flow path through which filtrate of the concentrated liquid that has passed through the first filter flows; and a filtrate storage unit connected to the second flow path and configured to store the filtrate.

[0065] [E4] The processing system according to [E3], further comprising a third flow path downstream of the filtrate reservoir, and a bypass flow path connecting the third flow path and the second flow path, and further comprising a liquid delivery unit that pressurizes the liquid in the bypass flow path to cause the liquid to flow back in the second flow path and flow into the first flow path from the outlet side of the first filter.

[0066] [E5] A processing system as described in [E4], further comprising a fourth flow path provided with a second filter, wherein the filtrate storage section has a first storage section connected to the second flow path and a second storage section connected to the third flow path, and the fourth flow path connects the first storage section and the second storage section.

[0067] [E6] The processing system according to any one of [E1] to [E5], further comprising a first gas filter that separates the gas volatilized by the chemical treatment unit into an organic fluorine compound-rich gas and an organic fluorine compound-removed gas.

[0068] [E7] The processing system according to [E6], wherein the first gas filter receives heat generated in the chemical liquid processing unit and is made to have a higher temperature than the concentrated liquid.

[0069] [E8] The processing system according to any one of [E1] to [E7], further comprising a second gas filter that takes in outside air and separates the outside air into a first diverted gas having a higher nitrogen concentration than air and a second diverted gas having a higher oxygen concentration than air, and the second gas filter supplies the first diverted gas to the chemical solution treatment unit.

[0070] [E9] The treatment system according to [E8], further comprising a combustion detoxification device that combusts and detoxifies organic fluorine compounds contained in the gas volatilized by the chemical treatment device, and the second gas filter supplies the second diverted gas to the combustion detoxification device.

[0071] [E10] A treatment method including: a concentration step of concentrating waste liquid containing an organic fluorine compound discharged from a semiconductor manufacturing device; and a chemical treatment step of decomposing and volatilizing the concentrated liquid concentrated in the concentration step.

[0072] [E11] The treatment method according to [E10], further comprising a filter cleaning step of cleaning the first filter by flowing filtrate of the concentrated liquid that has passed through the first filter from the outlet side of the first filter used in the concentration step.

[0073] [E12] The treatment method according to [E10] or [E11], further comprising a gas separation step of separating the gas volatilized in the chemical treatment step into an organic fluorine compound-rich gas and an organic fluorine compound-removed gas using a first gas filter.

[0074] [E13] The processing method according to any one of [E10] to [E13], further comprising a gas supply step of supplying the first diverted gas to a processing unit that performs the chemical solution processing step, wherein the second gas filter separates the outside air into a first diverted gas having a higher nitrogen concentration than air and a second diverted gas having a higher oxygen concentration than air.

[0075] [E14] A processing system comprising: a developer concentrating unit that concentrates waste liquid containing a positive developer discharged from a semiconductor manufacturing device; and a chemical processing unit that decomposes and volatilizes a first concentrated liquid concentrated by the developer concentrating unit.

[0076] [E15] The processing system according to [E14], further comprising a first supply path that supplies the waste liquid containing the positive developer to the developer concentrating section, the first supply path being provided separately from a second supply path that supplies the waste liquid having a higher resist concentration than the waste liquid containing the positive developer to a decomposition processing section corresponding to the waste liquid.

[0077] [E16] The processing system according to [E14] or [E15], wherein the chemical treatment unit decomposes and volatilizes the first concentrated liquid by heat.

[0078] [E17] The processing system according to any one of [E14] to [E16], wherein the chemical liquid processing unit is provided adjacent to a decomposition processing unit for a second concentrated liquid having a resist concentration higher than that of the first concentrated liquid.

[0079] [E18] The treatment system according to [E17], further comprising a combustion detoxification device for detoxifying organofluorine compounds by combustion, the combustion detoxification device having a combustion chamber for mixing and combusting a gas related to the first concentrated liquid volatilized by the chemical liquid treatment unit and a gas related to the second concentrated liquid volatilized by the decomposition treatment unit.

[0080] [E19] The processing system according to any one of [E14] to [E18], further comprising: a first supply path that supplies waste liquid containing the positive developer to the developer concentrating section, the first supply path having a filter for waste liquid containing the positive developer disposed therein; a filtrate flow path through which flows filtrate that has passed through a filter for concentrating waste liquid having a higher resist concentration than the waste liquid containing the positive developer; and a bypass flow path that connects the filtrate flow path and the first supply path. The processing system further comprises a liquid delivery section that pressurizes the filtrate in the bypass flow path to reverse the flow of the filtrate in the first supply path and causes the filtrate to flow from an outlet side of the filter for waste liquid containing the positive developer.

[0081] [E20] The processing system according to [E19] further comprises: a waste liquid storage section for storing waste liquid having a higher resist concentration than waste liquid containing the positive developer; and a backflow liquid storage section for storing backflow liquid flowing out from an inlet side of a filter for waste liquid containing the positive developer when the filtrate flows in from an outlet side of the filter. The processing system according to [E19] further comprises: a recovery flow path connecting the backflow liquid storage section and the waste liquid storage section, and for sending the backflow liquid from the backflow liquid storage section to the waste liquid storage section.

[0082] [E21] A processing method including: a developer concentrating step of concentrating waste liquid containing a positive developer discharged from a semiconductor manufacturing device; and a chemical treatment step of decomposing and volatilizing a first concentrated liquid concentrated in the developer concentrating step.

[0083] [E22] The processing method according to [E21], wherein in the chemical liquid processing step, the first concentrated liquid is decomposed and volatilized using heat generated by a reaction related to decomposition of a second concentrated liquid having a higher resist concentration than the first concentrated liquid.

[0084] [E23] The treatment method according to [E21] or [E22], further comprising a filter washing step of washing the filter used in the developer concentrating step by introducing, from an outlet side of the filter used in the developer concentrating step, filtrate that has passed through a filter other than the filter used in the developer concentrating step and that is used to concentrate a waste liquid having a higher resist concentration than the waste liquid containing the positive developer.

[0085] 1...PFAS detoxification system, 11...concentrator, 12...sulfuric acid treatment tank, 13...cooler, 14...detoxification device, 100...semiconductor manufacturing equipment, 111...lithography equipment, 112...cleaning equipment, 113...etching equipment, 114...film formation equipment.

Claims

1. A processing system comprising: a developer concentrating unit that concentrates waste liquid containing a positive developer discharged from semiconductor manufacturing equipment; and a chemical processing unit that decomposes and volatilizes the first concentrated liquid concentrated by the developer concentrating unit.

2. A processing system as described in claim 1, further comprising a first supply path for supplying waste liquid containing the positive developer to the developer concentrating section, said first supply path being provided separately from a second supply path for supplying waste liquid having a higher resist concentration than the waste liquid containing the positive developer to a decomposition processing section corresponding to said waste liquid.

3. The processing system according to claim 1, wherein the chemical processing unit decomposes and volatilizes the first concentrated liquid by heat.

4. The processing system according to claim 3, wherein the chemical processing section is provided adjacent to a decomposition processing section for a second concentrated liquid having a resist concentration higher than that of the first concentrated liquid.

5. A treatment system as described in claim 4, further comprising a combustion detoxification device that detoxifies organic fluorine compounds by combustion, said combustion detoxification device having a combustion chamber that mixes and burns gas related to the first concentrated liquid volatilized by the chemical treatment device and gas related to the second concentrated liquid volatilized by the decomposition treatment device.

6. A processing system according to any one of claims 1 to 5, further comprising: a first supply path that supplies waste liquid containing the positive developer to the developer concentrating section and that has a filter for waste liquid containing the positive developer installed along the way; a filtrate flow path through which flows filtrate that has passed through a filter for concentrating waste liquid having a higher resist concentration than the waste liquid containing the positive developer; a bypass flow path that connects the filtrate flow path and the first supply path; and a liquid delivery section that pressurizes the filtrate in the bypass flow path to reverse the flow in the first supply path and cause the filtrate to flow in from the outlet side of the filter for waste liquid containing the positive developer.

7. A processing system as described in claim 6, further comprising: a waste liquid storage section for storing waste liquid having a higher resist concentration than waste liquid containing said positive developer; a backflow liquid storage section for storing backflow liquid flowing out from the inlet side of a filter for waste liquid containing said positive developer when said filtrate flows in from the outlet side of said filter; and a recovery flow path connecting said backflow liquid storage section and said waste liquid storage section, and sending said backflow liquid from said backflow liquid storage section to said waste liquid storage section.

8. A processing method comprising: a developer concentrating step of concentrating waste liquid containing a positive developer discharged from a semiconductor manufacturing device; and a chemical treatment step of decomposing and volatilizing the first concentrated liquid concentrated in the developer concentrating step.

9. A processing method according to claim 8, wherein in the chemical processing step, the first concentrated liquid is decomposed and volatilized using heat generated by a reaction related to the decomposition of a second concentrated liquid having a higher resist concentration than the first concentrated liquid.

10. A processing method according to claim 8 or 9, further comprising a filter washing step of washing the filter used in the developer concentrating step by flowing in, from the outlet side of the filter used in the developer concentrating step, filtrate that has passed through a filter other than the filter used in the developer concentrating step and that is used to concentrate waste liquid having a higher resist concentration than waste liquid containing the positive developer.

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