Treatment device and treatment method

Abstract

Provided are a treatment device and a treatment method whereby a discharged portion related to semiconductor manufacturing can be efficiently removed or rendered harmless.　The treatment device treats a resist-containing first waste liquid discharged from a lithography device and comprises: a first filter (39) that separates the first waste liquid into liquids having different component concentrations; and a collected matter removal unit that removes collected matter inside the first filter. The collected matter removal unit has a permeation-promoting liquid supply part (50) that supplies, to the first filter, a permeation-promoting liquid that promotes permeation of the collected matter into the first filter (39).

Description

Processing device and processing method

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

[0002] Patent Document 1 discloses a technique for regenerating a filter that has become clogged with particles from an etching processing liquid column.

[0003] Japanese Patent Application Publication No. 6-310487

[0004] The present disclosure provides a processing apparatus and processing method that can efficiently remove or neutralize exhaust parts involved in semiconductor manufacturing.

[0005] A processing apparatus according to one aspect of the present disclosure is a processing apparatus for processing a first waste liquid containing resist discharged from a lithography apparatus, and includes a first filter that separates the first waste liquid into liquids with different component concentrations, and a collected matter removal unit that removes collected matter from the first filter, and the collected matter removal unit has a permeation promoting liquid supply unit that supplies the first filter with a permeation promoting liquid that promotes permeation of the collected matter into the interior of the first filter.

[0006] According to the present disclosure, waste materials related to semiconductor manufacturing can be efficiently removed or rendered harmless.

[0007] It is a schematic diagram of a processing system according to the present embodiment. It is a configuration diagram of the PFAS detoxification system shown in Figure 1. It is a diagram schematically showing a filter and piping configuration related to concentration of resist waste liquid. It is a diagram explaining an example of a configuration related to supply of a permeation promoting liquid. It is a diagram explaining another example of a configuration related to supply of a permeation promoting liquid.

[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] [First Embodiment] Fig. 1 is a schematic diagram of a processing system according to this embodiment. As shown in Fig. 1, the processing system includes a PFAS detoxification system 1 (processing apparatus) and a semiconductor manufacturing apparatus 100. In the processing system, the PFAS detoxification system 1 detoxifies PFAS discharged from the semiconductor manufacturing apparatus 100. Note that Fig. 1 shows a schematic configuration of the PFAS detoxification system 1, and some components (e.g., 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 includes organic polymer compounds (polymers) such as Teflon (registered trademark). 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 is 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 PFAS from being discharged to the outside. The PFAS detoxification system 1 functions as a treatment device that treats waste liquid discharged from the semiconductor manufacturing apparatus 100. Specifically, the PFAS detoxification system 1 is a treatment device that treats resist-containing waste liquid (first waste liquid) discharged from a lithography apparatus 111 (described below).

[0012] As shown in FIG. 1 , the PFAS detoxification system 1 includes a concentrator 11, a sulfuric acid treatment tank 12, a cooler 13, and a detoxification device 14. 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 formation apparatus 114. Each component of the semiconductor manufacturing apparatus 100 discharges substances containing PFAS during processing. The processing units constituting the PFAS detoxification system 1 may or may not be located in the same space (location). For example, each processing unit may be located within the building in which the lithography apparatus 111, the cleaning apparatus 112, or the etching apparatus 113 is located, or may be located outside the building or in an adjacent space. Each treatment unit may be installed separately, either inside or outside the building. Furthermore, among the concentrator 11, sulfuric acid treatment tank 12, cooler 13, and detoxification device 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 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 PFAS-containing resist waste liquid 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 a PFAS-containing waste liquid. As described below, the concentrator 11 includes a polymer concentrator 11a and a monomer concentrator 11b (see FIG. 2 ), but here they will be described as the concentrator 11 without distinguishing between them. The concentrator 11 uses, for example, an ultrafiltration membrane or a reverse osmosis membrane to concentrate the resist waste liquid and separate the solvent contained in the resist waste liquid (details will be described later). The concentrated resist waste liquid contains a polymer, so it has a high viscosity. The concentrated resist waste liquid is introduced into the sulfuric acid treatment tank 12. When the alkaline waste liquid discharged from the lithography tool 111 is concentrated by the concentrator 11, the alkaline waste liquid may be neutralized before being introduced into the reverse osmosis membrane.

[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 liquid is added to the SPM waste liquid 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 Fig. 2. Fig. 2 is a configuration diagram of the PFAS detoxification system 1 shown in Fig. 1. Fig. 2 also shows configurations (such as configurations related to TMAH waste liquid) that are omitted from Fig. 1. Note that Fig. 2 omits the configuration related to the supply of a permeation promoter liquid, which will be described later.

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

[0028] Resist waste liquid containing PFAS discharged from the lithography apparatus 111 flows through the waste liquid supply path 15 and into a polymer filter 301 provided in the waste liquid supply path 15. The polymer filter 301 separates the resist waste liquid into a polymer concentrate having a polymer (high molecular weight component) concentration equal to or greater than a predetermined concentration and a monomer concentrate having a monomer (low molecular weight component) concentration equal to or greater than a predetermined concentration but not equal to a predetermined concentration. 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 filter (filter 39, etc.) used to extract the filtrate (solvent), which will be 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. The monomer concentrate separated by the polymer filter 301 is stored in the monomer concentrator 11b. In this manner, the monomer concentrator 11b is a storage unit that stores the monomer concentrate.

[0029] The circulation flow path 16 is a circulation flow path connected to the monomer concentrator 11b, and a filter 39 for removing polymer 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 monomer concentrate. The filtrate (solvent) that passes through the filter 39 flows through the first filtrate flow path 17a and is stored in the first reservoir 20xa. This filtrate is a low-concentration PFAS solution. The first reservoir 20xa is connected to the first filtrate flow path 17a and serves as a reservoir for storing the filtrate. The second filtrate flow path 17b is a flow path connecting the first reservoir 20xa and the second reservoir 20xb. The second filtrate flow path 17b is provided with a filter 40a. The filter 40a is, for example, an ion exchange resin filter. The provision of the filter 40a allows the filtrate that passes through the filter 40a to be a solution with a low PFAS content. The filtrate (solvent) that has passed through the filter 40a flows through the second filtrate flow path 17b and is stored in the second reservoir 20xb. The second reservoir 20xb is connected to the third filtrate flow path 18 and serves as a reservoir for storing the filtrate. The third filtrate flow path 18 is a flow path connecting the second reservoir 20xb and the third reservoir 20y. The third filtrate flow path 18 is provided with a filter 40b. The filter 40b is, for example, an ion exchange resin filter. By providing the filter 40b, the filtrate that has passed through the filter 40b can be made into a solution that contains almost no PFAS. The filtrate that has passed through the filter 40b flows through the third filtrate flow path 18 and is stored in the third reservoir 20y. This filtrate can be used as a regenerated solvent and flows to the outside from the fourth filtrate flow path 19 downstream of the third reservoir 20y.

[0030] The filtrate may be introduced (backflowed) from the outlet side of the polymer filter 301 via, for example, the third filtrate flow path 18 and the bypass flow path 302. This allows clogging of the polymer filter 301 with polymer components and the like to be eliminated. Such backflow of the filtrate may be achieved, for example, by gas pressure or a liquid delivery unit such as a pump. Because the polymer solution has a high concentration and viscosity, for example, a large amount of solvent is required to wash it away with a solvent. Furthermore, other methods require treatments such as UV irradiation, ozone oxidation, and plasma exposure. In this regard, the method of backflowing the filtrate allows for easy and appropriate cleaning of the polymer filter 301 without the need to prepare a separate solvent or perform UV irradiation or the like.

[0031] The components of the monomer concentrator 11b, circulation flow path 16, filters 39, 40a, 40b, first filtrate flow path 17a, first reservoir 20xa, second filtrate flow path 17b, second reservoir 20xb, and third filtrate flow path 18 constitute a low-molecular-weight component treatment section. The low-molecular-weight component treatment section increases the concentration of low-molecular-weight components such as PFAS in the monomer concentrate separated by the polymer filter 301. The components of the low-molecular-weight component treatment section, particularly the circulation flow path 16 and filter 39, function as a circulation filtration mechanism that circulates the monomer concentrate and filters out low-molecular-weight components. The components of the filters 40a, 40b, first filtrate flow path 17a, first reservoir 20xa, second filtrate flow path 17b, second reservoir 20xb, and third filtrate flow path 18 function as a purification mechanism that removes PFAS from the filtrate that has passed through the circulation filtration mechanism.

[0032] The components downstream of the waste liquid supply path 15, such as the polymer filter 301 and the low molecular weight component treatment section, 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 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 a first gas filter 22. The first gas filter 22 is a filter that 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 pervaporation filter, but may also be a ceramic filter. The first gas filter 22 receives heat generated in the sulfuric acid treatment tank 12 and is heated to a temperature higher than that of the concentrated liquid before decomposition. 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, so as to receive the 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. 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, and when 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 pervaporation filter, separates gases by utilizing the difference in momentum due to differences in molecular weight. That is, by reducing the pressure downstream of the first gas filter 22, for example, 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). This allows for the PFAS-rich gas to be largely separated from the PFAS-removed gas.

[0035] 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. 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.

[0036] 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 gas with a higher nitrogen concentration than air (hereinafter simply referred to as nitrogen) and a gas with a higher oxygen concentration than air (hereinafter simply referred to as oxygen). The second gas filter 25 then supplies the nitrogen to the sulfuric acid treatment tank 12, thereby preventing ignition in the sulfuric acid treatment tank 12. The second gas filter 25 also supplies oxygen to the detoxification device 14, thereby promoting 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 of generating ozone from oxygen may be, for example, UV irradiation or electrical discharge.

[0037] In the PFAS detoxification system 1, a TMAH waste liquid, which is a positive developer, is introduced from, for example, the lithography tool 111. In the PFAS detoxification system 1, the TMAH waste liquid discharged from the lithography tool 111 of the semiconductor manufacturing equipment 100 is concentrated in the concentrator 27. In addition, the first concentrated liquid, which is a concentrated liquid of the positive developer concentrated by the concentrator 27, is decomposed and volatilized in the developer treatment tank 31.

[0038] The waste liquid supply path 26 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, which 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 filter 41 is a developer waste liquid filter that removes polymers from the TMAH waste liquid. The circulation flow path 28 is a circulation flow path connected to the concentrator 27, and a filter 42 for increasing the concentration of PFAS is provided midway along the flow path. The developer (PFAS-free developer) that passes through the filter 42 passes through the developer flow path 29 and is stored in the recycled developer storage section 30. This developer can be used as recycled developer. The filter 42 is a positive developer waste liquid treatment section that separates the TMAH waste liquid into a PFAS-concentrated developer and a PFAS-free developer. The PFAS-free developer may be caused to flow backward from the secondary side of the filter 41. The backward flow liquid reservoir 35 is a developer filter cleaning liquid chamber that stores the liquid that has flowed backward and passed through the filter 41 in this manner.

[0039] The concentrated solution 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 described above. 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. Furthermore, the first concentrated solution may be used as a cooling solvent for the SPM in the sulfuric acid treatment tank 12.

[0040] 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 .

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

[0042] 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 the 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 from 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.

[0043] 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 becomes carbon dioxide, which is discharged, and the filter 43 is cleaned.

[0044] As described above, the resist waste liquid (first waste liquid containing resist) discharged from the lithography apparatus 111 is concentrated by passing through a plurality of filters and piping configurations. Fig. 3 is a diagram schematically showing a filter / piping configuration related to the concentration of the resist waste liquid. Note that Fig. 3 shows only a part of the configuration shown in Fig. 2, and also shows configurations not shown in Fig. 2.

[0045] 3, the resist waste liquid flowing through the waste liquid supply path 15 is pumped by the pump 151 and flows into the polymer filter 301 (second filter). The polymer filter 301 separates the resist waste liquid into a polymer concentrate (polymer solution) having a polymer (polymer component) concentration equal to or higher than a predetermined concentration, and a monomer concentrate (low molecular weight solution) having a monomer (low molecular weight component) concentration equal to or higher than a predetermined concentration. The polymer filter 301 is provided upstream of the filter 39 (first filter).

[0046] The monomer concentrate separated by the polymer filter 301 is stored in the monomer concentrator 11b and then flows through the circulation flow path 16. The monomer concentrate flowing through the circulation flow path 16 is pumped by the pump 161 and flows into the filter 39 (first filter). The filter 39 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 filter, and separates the monomer concentrate into a monomer concentrate (first solution) having a monomer concentration equal to or greater than a predetermined concentration, and a filtrate (second solution) that is a low-concentration PFAS solution having a monomer concentration equal to or less than a predetermined concentration. In Figure 2, the first storage section 20xa, the second storage section 20xb, the first filtrate flow path 17a, the second filtrate flow path 17b, the filter 40a, etc. are described as components related to the filtrate, but for the sake of convenience, these will be omitted here and the only components will be the storage section 20x that stores the filtrate and the filtrate flow path 17.

[0047] The filtrate separated by the filter 39 ("filtrate 1" in FIG. 3) is stored in the reservoir 20x and then flows through the filtrate flow path 17. The filtrate flowing through the filtrate flow path 17 is pumped by the pump 171 and flows into the filter 40b. The filter 40b is, for example, an ion exchange resin filter. The filtrate that has passed through the filter 40b is a solution that contains almost no PFAS. The filtrate that has passed through the filter 40b ("filtrate 2" in FIG. 3) flows through the third filtrate flow path 18 and is stored in the third reservoir 20y.

[0048] 3, in which resist waste liquid is concentrated using multiple filters, clogging of the filters (polymer filter 301, filters 39, 40b) may occur due to collected materials such as polymer components or PFAS. A configuration for regenerating such filters by removing the collected materials will be described below. In this embodiment, an example will be described in which a permeation promoter liquid is supplied to filter 39, which is a hollow fiber filter that collects PFAS, to remove the collected material, PFAS. The technology described below can be applied to systems other than the PFAS detoxification system, and can also be applied to systems other than filter 39, which is a hollow fiber filter.

[0049] Fig. 4 is a diagram illustrating a configuration related to the supply of permeation promoting liquid. In the configuration shown in Fig. 4, a permeation promoting liquid supply unit 50 is provided as a configuration related to the supply of permeation promoting liquid. The permeation promoting liquid supply unit 50 is a configuration of a collected matter removal unit that removes PFAS, which is a collected matter in the filter 39. The permeation promoting liquid supply unit 50 supplies the filter 39 with a permeation promoting liquid that promotes the permeation of the collected matter into the interior of the filter 39.

[0050] In the example shown in FIG. 4 , the permeation promoter liquid supply unit 50 passes the permeation promoter liquid through the filter 39 from the inlet side (upstream side). That is, the permeation promoter liquid supply unit 50 causes the permeation promoter liquid to flow forward into the filter 39. In this case, for example, a flow path 51 connected to the permeation promoter liquid supply unit 50 may be arranged to merge with a flow path connecting the pump 161 and the filter 39, thereby allowing the permeation promoter liquid to flow forward into the filter 39. The permeation promoter liquid causes PFAS to pass through the filter 39, thereby eliminating clogging of the filter 39. Note that the permeation promoter liquid reduces the filtering capacity of the filter 39 (allowing PFAS to pass through the interior of the filter 39) (details will be described later), so it is not preferable to return it to the monomer concentrator 11b. Therefore, the permeation promoter liquid that has passed through the filter 39 may be passed via a flow path 52 to a reservoir 53 that stores a PFAS supernatant and then discarded.

[0051] The solvent of the permeation promoter liquid has a polarity corresponding to the solvent of the resist contained in the resist waste liquid. That is, when the solvent of the resist contained in the resist waste liquid is an aprotic polar solvent, the solvent of the permeation promoter liquid is an aprotic polar solvent. On the other hand, when the solvent of the resist contained in the resist waste liquid is a protic polar solvent, the solvent of the permeation promoter liquid is a protic polar solvent.

[0052] Solvents are generally divided into nonpolar solvents, aprotic polar solvents, and protic polar solvents. Nonpolar solvents include, for example, hexane, benzene, toluene, 1,4-dioxane, chloroform, and diethyl ether. Aprotic polar solvents include, for example, PGMEA, NMP, DCM, THF, ethyl acetate, dichloromethane, acetone, DMF, acetonitrile, DMSO, and propylene glycols. Protic polar solvents are those that can be treated as acids, such as formic acid, acetic acid, most alcohols, nitromethane, hydrogen fluoride, ammonia, and water.

[0053] An aprotic polar solvent or a protic polar solvent is used as the solvent for the resist. This is because polymers and PAGs have various properties, and it is difficult to dissolve them in a nonpolar solvent. An aprotic polar solvent is usually used as the solvent for the resist. Therefore, an aprotic polar solvent is also used as the solvent for the permeation promoter liquid.

[0054] The resist solvent in the resist waste liquid and the solvent in the permeation promoter liquid may differ from each other by two or more polarization terms in the Hansen Solubility Parameter (HSP). The HSP is a value used to predict the solubility of a substance and is composed of three terms: a dispersion term, a polarization term, and a hydrogen bonding term.

[0055] The reason why the solvent of the permeation promoter is selected to have the same polarity (e.g., an aprotic polar solvent) as the solvent of the resist waste liquid but with a polarization term that differs by two or more is explained below. PFAS molecules are dissolved in an association state (cluster state) with solvent molecules. An association state is an unstable state with a bond energy weaker than that of a chemical bond. The permeation promoter attempts to disrupt the relationship between the PFAS in a cluster state and the solvent, creating a new cluster state, which destabilizes the cluster state surrounding the PFAS. By utilizing this unstable state, the collected material (PFAS) is forced to flow into the filter 39. The dispersion term, polarization term, and hydrogen bond term of a solvent are determined by the balance of the constituent atoms. However, by using a permeation promoter with a polarization term that differs by two or more, the existing balance in the resist waste liquid is disrupted, making it possible to disrupt the stable state of the clusters in the resist waste liquid. As described above, by using a solvent for the permeation promoter that has the same polarity as the solvent for the resist waste liquid (e.g., an aprotic polar solvent) and has two or more different polarization terms, the collected substance (PFAS) can be appropriately removed.

[0056] The permeation promoter liquid supply unit 50 may supply, as the permeation promoter liquid, a liquid recovered from a waste liquid (second waste liquid) different from the above-mentioned resist waste liquid (first waste liquid) discharged from the lithography apparatus 111 to the filter 39. In the case where a PFAS concentration system for the waste liquid (second waste liquid) different from the resist waste liquid (first waste liquid) exists, either a "PFAS concentrated liquid" or a "filtrate" obtained after removing polymers from the waste liquid may be used as the permeation promoter liquid for removing the collected matter in the filter 39. The permeation promoter liquid supply unit 50 may supply a newly prepared permeation promoter liquid instead of the waste liquid.

[0057] The configuration of the permeation promoting liquid supply unit is not limited to the embodiment shown in Fig. 4. Fig. 5 is a diagram illustrating another configuration example (permeation promoting liquid supply unit 50A) related to the supply of permeation promoting liquid. In the example shown in Fig. 5, the permeation promoting liquid supply unit 50A passes the permeation promoting liquid through the filter 39 from the outlet side (downstream side of the filter 39) of the filtrate (second solution). In this case, for example, a flow path 51A connected to the permeation promoting liquid supply unit 50A may be arranged to merge with a flow path connecting the filter 39 and the reservoir 20x, thereby allowing the permeation promoting liquid to flow back into the filter 39.

[0058] Furthermore, the collected matter removal section that removes PFAS, which is a collected matter in the filter 39, may be configured with a configuration other than the permeation promoter liquid supply section 50 (or permeation promoter liquid supply section 50A) described above. The collected matter removal section may have a heating section that raises the temperature of the filter 39 or the liquid passing through the filter 39. In this way, raising the temperature of the filter 39 or the liquid passing through the filter 39 makes the clusters unstable, making it easier for the collected matter to permeate into the filter 39, and the collected matter in the filter 39 can be appropriately removed.

[0059] The collected matter removal unit may also have a pressurizing unit that applies a pressure change (pulsation) to the liquid passing through the filter 39 by using the pump 161 in a different way than usual, thereby removing the collected matter from the filter 39. The pressurizing unit may generate the pressure change by, for example, microbubbles or nanobubbles.

[0060] Next, the effects of the PFAS detoxification system 1 (treatment device) according to this embodiment will be described.

[0061] The PFAS detoxification system 1 is a processing device that processes resist-containing resist waste liquid (first waste liquid) discharged from a lithography apparatus 111. The PFAS detoxification system 1 includes a filter 39 that separates the resist waste liquid into liquids with different component concentrations, and a collected matter removal unit that removes collected matter from the filter 39. The collected matter removal unit has a permeation promoter liquid supply unit 50 that supplies the filter 39 with a permeation promoter liquid that promotes permeation of the collected matter into the inside of the filter 39.

[0062] With this configuration, the permeation promoter liquid is supplied to the filter 39, which allows the trapped substances (PFAS) to easily permeate the interior of the filter 39, thereby effectively removing the trapped substances from the filter 39. This allows the trapping performance of the filter 39 to be regenerated even after some use. This allows the PFAS detoxification system to efficiently remove or detoxify wastes related to semiconductor manufacturing.

[0063] The filter 39 separates the solution into a first solution that is concentrated to a high concentration through the filter and a second solution in which low-molecular-weight components have been filtered out and reduced in concentration, and the permeation promoter liquid supply unit 50A may pass the permeation promoter liquid through the filter 39 from the outlet side of the second solution. By supplying the permeation promoter liquid from the outlet side of a filter (e.g., a hollow fiber filter) that separates low-molecular-weight components according to their concentration, the captured materials such as PFAS that have been captured on the upstream inner surface of the filter can be washed away from the downstream side, thereby properly removing the captured materials.

[0064] The filter 39 is a filter that separates the solution into a first solution having a predetermined concentration or more of low-molecular-weight components and a second solution having a predetermined concentration or less of low-molecular-weight components, and the permeation promoter liquid supply unit 50 may pass the permeation promoter liquid through the inlet side of the filter 39. When the permeation promoter liquid is supplied from the inlet side of a filter (e.g., a hollow fiber filter) that separates low-molecular-weight components according to their concentration, the low-molecular-weight components are in an unstable cluster state, which allows them to pass through the meshes of the filter, thereby allowing the PFAS and other captured substances to be appropriately removed.

[0065] The PFAS detoxification system 1 may further include a polymer filter 301, which is provided upstream of the filter 39 and separates the resist waste liquid into a polymer solution having a predetermined concentration or more of polymer components and a low molecular weight solution having a predetermined concentration or more of low molecular weight components. The filter 39 may separate the low molecular weight solution into a first solution and a second solution. With this configuration, the filter that separates the monomer concentrate can appropriately remove trapped substances such as PFAS.

[0066] The permeation promoting liquid supply unit 50 may supply, as the permeation promoting liquid, a liquid recovered from a second waste liquid that is different from the first waste liquid and that is discharged from the lithography apparatus 111 to the filter 39. With this configuration, the permeation promoting liquid can be prepared smoothly and easily by effectively utilizing the other waste liquid.

[0067] When the resist solvent contained in the resist waste liquid is an aprotic polar solvent, the solvent of the permeation promoter liquid may be an aprotic polar solvent, and when the resist solvent contained in the resist waste liquid is a protic polar solvent, the solvent of the permeation promoter liquid may be a protic polar solvent. In this way, by making the polarity of the solvents the same, the permeation promoter liquid can attack the resist waste liquid to disrupt its stable state. This allows the collected matter on the filter 39 to be properly removed.

[0068] The resist solvent and the permeation promoter solvent contained in the resist waste liquid may have polarization terms that differ by two or more. By using a permeation promoter liquid with polarization terms that differ by two or more, the existing balance in the resist waste liquid is disrupted, and the stable state of clusters in the resist waste liquid can be disrupted. This allows the collected matter on the filter 39 to be appropriately removed.

[0069] Finally, various exemplary embodiments included in the present disclosure are described below in [E1] to [E14].

[0070] [E1] A processing apparatus for processing a first waste liquid containing resist discharged from a lithography apparatus, the processing apparatus comprising: a first filter that separates the first waste liquid into liquids having different component concentrations; and a collected matter removal unit that removes collected matter in the first filter, wherein the collected matter removal unit has a permeation promoting liquid supply unit that supplies the first filter with a permeation promoting liquid that promotes permeation of the collected matter into the inside of the first filter.

[0071] [E2] The treatment device according to [E1], wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the permeation promoter liquid supply unit passes the permeation promoter liquid through the first filter from the outlet side of the second solution.

[0072] [E3] The treatment device according to [E1], wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the permeation promoter liquid supply unit passes the permeation promoter liquid through the first filter from an inlet side.

[0073] [E4] The treatment device according to any one of [E1] to [E3], further comprising a second filter provided upstream of the first filter for separating the first waste liquid into a polymer solution having a predetermined concentration or more of polymer components and a low molecular weight solution having a predetermined concentration or more of low molecular weight components, wherein the first filter separates the low molecular weight solution into the first solution and the second solution.

[0074] [E5] A processing apparatus according to any one of [E1] to [E4], wherein the permeation promoting liquid supply unit supplies a liquid recovered from a second waste liquid discharged from the lithography apparatus, the second waste liquid being different from the first waste liquid, to the first filter as the permeation promoting liquid.

[0075] [E6] The processing apparatus according to any one of [E1] to [E5], wherein when the solvent of the resist contained in the first waste liquid is an aprotic polar solvent, the solvent of the permeation promoter liquid is an aprotic polar solvent, and when the solvent of the resist contained in the first waste liquid is a protic polar solvent, the solvent of the permeation promoter liquid is a protic polar solvent.

[0076] [E7] The processing apparatus according to [E6], wherein the solvent of the resist contained in the first waste liquid and the solvent of the permeation promoter liquid have polarization terms that differ from each other by two or more.

[0077] [E8] A method for treating a first waste liquid containing resist discharged from a lithography apparatus, comprising: a step of sorting the first waste liquid into liquids having different component concentrations using a first filter; and a step of removing collected matter from within the first filter, wherein in the step of removing collected matter, a permeation promoting liquid that promotes permeation of the collected matter into the inside of the first filter is supplied to the first filter.

[0078] [E9] The treatment method according to [E8], wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the step of removing the captured matter comprises passing the permeation promoter liquid through the first filter from the outlet side of the second solution.

[0079] [E10] The treatment method according to [E8], wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the step of removing the captured matter comprises passing the permeation promoter liquid through the first filter from an inlet side.

[0080] 1...PFAS detoxification system (treatment device), 39...filter (first filter), 50, 50A...permeation promoting liquid supply section, 111...lithography device, 301...polymer filter (second filter).

Claims

1. A processing device for processing a first waste liquid containing resist discharged from a lithography device, comprising: a first filter that separates the first waste liquid into liquids with different component concentrations; and a collected matter removal unit that removes collected matter from within the first filter, wherein the collected matter removal unit has a permeation promoting liquid supply unit that supplies the first filter with a permeation promoting liquid that promotes permeation of the collected matter into the interior of the first filter.

2. A processing device as described in claim 1, wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the permeation promoter liquid supply unit passes the permeation promoter liquid through the first filter from the outlet side of the second solution.

3. A processing device as described in claim 1, wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and the permeation promoter liquid supply unit passes the permeation promoter liquid through the first filter from the inlet side.

4. A treatment device as described in claim 2 or 3, further comprising a second filter provided upstream of the first filter for separating the first waste liquid into a polymer solution having a predetermined concentration or more of polymer components and a low molecular weight solution having a predetermined concentration or more of low molecular weight components, wherein the first filter separates the low molecular weight solution into the first solution and the second solution.

5. A processing device according to claim 2 or 3, wherein the permeation promoter liquid supply unit supplies a liquid recovered from a second waste liquid discharged from the lithography device, which is different from the first waste liquid, to the first filter as the permeation promoter liquid.

6. A processing apparatus according to claim 2 or 3, wherein when the solvent of the resist contained in said first waste liquid is an aprotic polar solvent, the solvent of said permeation promoter liquid is an aprotic polar solvent, and when the solvent of the resist contained in said first waste liquid is a protic polar solvent, the solvent of said permeation promoter liquid is a protic polar solvent.

7. The processing apparatus according to claim 6, wherein the solvent of the resist contained in said first waste liquid and the solvent of said permeation promoting liquid have polarization terms that differ from each other by two or more.

8. A method for treating a first waste liquid containing resist discharged from a lithography apparatus, comprising: a step of sorting the first waste liquid into liquids with different component concentrations using a first filter; and a step of removing collected matter from the first filter, wherein in the step of removing collected matter, a permeation promoting liquid that promotes permeation of the collected matter into the inside of the first filter is supplied to the first filter.

9. A treatment method according to claim 8, wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and in the step of removing the captured matter, the permeation promoting liquid is passed through the first filter from the outlet side of the second solution.

10. A treatment method according to claim 8, wherein the first filter is a filter that separates a first solution having a predetermined concentration or more of low molecular weight components from a second solution having a predetermined concentration or less of low molecular weight components, and in the step of removing the captured matter, the permeation promoting liquid is passed through the first filter from the inlet side.

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