Method for treating chemical solutions

Abstract

A method for treating a chemical solution is provided, the method including at least providing a system including at least one filtration medium, treating the system with a treatment solution having an iron (Fe) and calcium (Ca) content of about 10 ppb or less, and treating the chemical solution using an apparatus having the system therein after the treatment step.

Description

[Background technology]

[0001] 1. Related fields

[0002] The present invention relates to a method for treating chemical fluids, and more particularly to a method for purifying chemical fluids used in semiconductor manufacturing.

[0003] 2. Description of Related Technology

[0004] Due to the increasing demand for higher integration and higher performance of semiconductor devices such as large scale integrated circuits (LSI), new precision and higher resolution processing techniques are being developed and applied in the manufacture of LSI.

[0005] During the manufacture of high resolution integrated circuits, various process liquids come into contact with bare or film-coated wafers. For example, the manufacture of fine metal wiring structures typically involves coating a substrate with a pre-wetting liquid before the substrate is coated with a composite liquid to form a resist film, exposing the resist film to have a pattern shape, performing a development process by using a developer liquid, and cleaning the patterned resist film by using a rinse liquid. These process liquids, containing suitable components and various additives, are known sources of contaminants for IC wafers.

[0006] The presence of very low levels of metallic impurities, as low as 1.0 ppt, has been demonstrated to degrade the performance and stability of semiconductor devices, and depending on the type of impurity, can cause poor oxidation properties, imprecise patterning, and impaired electrical performance of semiconductor circuits, which ultimately impacts manufacturing yields.

[0007] These contaminants, such as metal impurities, coarse particles, organic impurities, moisture, etc., can be unintentionally introduced into a chemical solution during various stages of the chemical solution manufacturing process. For example, a chemical solution that is not properly prepared or processed and comes into contact with a piece of manufacturing (processing) equipment, and foreign matter can be leached or extracted from the surfaces of the manufacturing equipment, resulting in an undesired increase in trace metals, particles, and / or organic contaminants in the chemical solution.

[0008] As a result, it is essential that the standards and quality of the chemical manufacturing processes and manufacturing equipment used in these processes to produce the high purity chemicals necessary for the manufacture of ultra-fine and highly precise semiconductor electronic circuits be significantly improved and tightly controlled. Summary of the Invention

[0009] Therefore, the demand for ultra-high purity chemicals and the quality improvement and control of these fluids has become very important for forming high precision integrated circuits. Specific key parameters for quality improvement and control include trace metal reduction, liquid particle count reduction, on-wafer defect reduction, organic contaminant reduction, etc. All of these key parameters have been shown to be influenced by proper design of the manufacturing process and necessary provisioning of the manufacturing equipment.

[0010] In view of the above, the present invention provides a method for processing chemicals, particularly adapted for semiconductor manufacturing, whereby high purity chemicals are produced with the number of unwanted particles and the amount of metallic impurities in the chemicals controlled within predetermined ranges, thereby reducing the occurrence of residue and / or particle defects and improving the yield of semiconductor wafers.

[0011] According to some embodiments of the present invention, a method for treating a chemical solution includes providing a system including at least one filtration medium selected from a filter, an ion exchange membrane, and an ion adsorption membrane; performing a treatment process on the system using a treatment solution having iron (Fe) and calcium (Ca) contents limited to about 10 ppb or less; and treating the chemical solution with the system configured in the apparatus following the treatment process.

[0012] According to certain exemplary embodiments, the method includes configuring a system within the apparatus after the processing step.

[0013] According to certain exemplary embodiments, the method includes configuring a system within the device before the processing steps are performed.

[0014] According to an alternative embodiment of the present invention, a method for treating a chemical solution includes providing a first purification system including at least one first filtration medium selected from a first filter, a first ion exchange membrane, and a first ion adsorption membrane; performing a purification process on the chemical solution in the first purification system configured within a manufacturing apparatus; and applying a first treatment solution to the at least one first filtration medium before the purification process is performed, wherein the iron (Fe) and calcium (Ca) content in the first treatment solution is preferably less than about 10 ppb.

[0015] According to certain exemplary embodiments, the method includes providing a second purification system including at least one second filtration medium selected from a second filter, a second ion exchange membrane, and a second ion adsorption membrane, and applying a second treatment liquid to the at least one second filtration medium before the purification step is performed, the second treatment liquid preferably having an iron (Fe) and calcium (Ca) content of less than about 10 ppb.

[0016] In accordance with the present invention, a method for treating chemicals is effectively designed and properly prepared to prevent the introduction of various organic and inorganic contaminants during the manufacturing process and to produce high purity chemicals applicable to semiconductor manufacturing. [Brief description of the drawings]

[0017] Aspects of the present invention are best understood from the following detailed description when read in conjunction with the accompanying drawing figures. It should be noted that, in accordance with standard practice in the industry, various features have not been drawn to scale. In fact, the dimensions of various features have been arbitrarily increased or decreased for clarity of presentation.

[0018] [Figure 1A] FIG. 1A is a flow diagram of steps in one exemplary method for treating a chemical fluid according to some embodiments of the present invention.

[0019] [Figure 1B] FIG. 1B is a flow diagram of steps in one exemplary method for treating a chemical fluid according to some embodiments of the present invention.

[0020] [Diagram 2] FIG. 2 is a schematic diagram illustrating an exemplary chemical fluid manufacturing apparatus adapted for methods for processing chemical fluids according to some embodiments of the present invention.

[0021] [Diagram 3] FIG. 3 presents the results of OWMC (On Wafer Metal Count) as a function of cleaning cycles. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The following disclosure provides many different embodiments or examples for implementing different features of the provided subject matter. To simplify the disclosure, specific examples of components and configurations are described below. Of course, these are merely examples and are not intended to be limiting. For example, when the term "solvent" is used, unless otherwise stated (unless otherwise specified), it refers to a single solvent or a combination of two or more solvents. In addition, the disclosure may repeat reference numbers and / or letters in various examples. This repetition is for the purposes of brevity and clarity and does not in itself specify a relationship between the various embodiments and / or configurations being described.

[0023] Additionally, spatially relative terms such as "below," "lower," "upper," "top," and the like are used herein for ease of description to describe the relationship of one element or feature depicted in the figures to another element or feature. The spatially relative terms are intended to encompass different orientations of the device during use or operation in addition to the orientation depicted in the figures. The device may be oriented in other ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0024] In the present invention, a numerical range indicated using the term "to" means a range including the numerical values ​​before and after the term "to" as the lower and upper limits.

[0025] In the present invention, "ppm" stands for "parts-per-million (10 -6 ) and "ppb" stands for "parts-per-billion (10 -9 )" and "ppt" stands for "parts-per-trillion (10 -12 )".

[0026] In the present invention, 1 Å (angstrom) corresponds to 0.1 nm (nanometer) and 1 μm (micron) corresponds to 1000 nm.

[0027] <Chemical solution>

[0028] In the present invention, the chemical liquid includes a wafer processing liquid such as a pre-wet liquid, a developer, a rinse liquid, a cleaning liquid, a stripping liquid, etc., or a raw material solvent used for the production thereof.

[0029] Prior to undergoing the processes of the present invention, including but not limited to purification processes, the chemical liquid may contain undesired amounts of contaminants and impurities. After the chemical liquid is processed by the chemical liquid production apparatus of the present invention, a substantial amount of the contaminants and impurities is removed from the chemical liquid. The chemical liquid after processing is referred to as the "processed chemical liquid" in the present invention. The "processed chemical liquid" may contain impurities that are controlled and limited within a predetermined range.

[0030] <Organic solvent>

[0031] In the present invention, the chemical solution contains an organic solvent. The type of the organic solvent is not particularly limited, but a well-known organic solvent is applicable. The content of the organic solvent in the chemical solution is not particularly limited, but the organic solvent is included as a main component. Specifically, the content of the organic solvent is 98% by mass or more with respect to the total mass of the chemical solution. In a specific embodiment, the content of the organic solvent is 99% by mass or more with respect to the total mass of the chemical solution. In another embodiment, the content of the organic solvent is 99.5% by mass or more with respect to the total mass of the chemical solution. In still another embodiment, the content of the organic solvent is 99.8% by mass or more with respect to the total mass of the chemical solution. The upper limit is not particularly limited, but usually the upper limit is 99.999% by mass or less.

[0032] The organic solvent may be used alone or in combination of two or more. When two or more organic solvents are used in combination, it is preferable that the total content is within the above range.

[0033] The content of the organic solvent in the chemical solution can be measured by using a gas chromatography mass spectrometry (GCMS) device.

[0034] The boiling point of the organic solvent is not particularly limited. However, from the viewpoint of improving the manufacturing yield of semiconductor chips, the boiling point of the organic solvent is preferably less than 200° C. In the present invention, the boiling point means the boiling point at 1 atm.

[0035] The organic solvent is not particularly limited. Examples of the organic solvent include methanol, ethanol, 1-propanol, isopropanol, n-propanol, 2-methyl-1-propanol, n-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, n-hexanol, cyclohexanol, 2-methyl-2-butanol, 3-methyl-2-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-methyl-3-pentanol, 3 ... 1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol, 2-ethyl-1-butanol, 2,2-dimethyl-3-pentanol, 2,3-dimethyl-3-pentanol, 2,4-dimethyl-3-pentanol, 4,4-dimethyl-2-pentanol, 3-ethyl-3-heptanol, 1-heptanol, 2-heptanol, 3-heptanol, 2-methyl-2-hexanol, 2-methyl-3-hexanol, 5-methyl-1-hexanol ethanol, 5-methyl-2-hexanol, 2-ethyl-1-hexanol, methylcyclohexanol, trimethylcyclohexanol, 4-methyl-3-heptanol, 6-methyl-2-heptanol, 1-octanol, 2-octanol, 3-octanol, 2-propyl-1-pentanol, 2,6-dimethyl-4-heptanol, 2-nonanol, 3,7-dimethyl-3-octanol, ethylene glycol, propylene glycol, diethyl ether, dipropyl ether, diisopropyl ether, butyl methyl ether butyl ethyl ether, butyl propyl ether, dibutyl ether, diisobutyl ether, tert-butyl methyl ether, tert-butyl ethyl ether, tert-butyl propyl ether, di-tert-butyl ether, dipentyl ether, diisoamyl ether, cyclopentyl methyl ether, cyclohexyl methyl ether, bromomethyl methyl ether, α,α-dichloromethyl methyl ether, chloromethyl ethyl ether, 2-chloroethyl methyl ether, 2-bromoethyl methyl ether, 2,2-Dichloroethyl methyl ether, 2-chloroethyl ethyl ether, 2-bromoethyl ethyl ether, (±)-1,2-dichloroethyl ethyl ether, 2,2,2-trifluoroethyl ether, ethyl vinyl ether, butyl vinyl ether, allyl ethyl ether, allyl propyl ether, allyl butyl ether, diallyl ether, 2-methoxypropene, ethyl-1-propenyl ether, cis-1-bromo-2-ethoxyethylene, 2-chloroethyl vinyl ether, allyl-1,1,2,2-tetrafluoroethyl ether, octane, isooctane, nonane, decane , methylcyclohexane, decalin, xylene, ethylbenzene, diethylbenzene, cumene, sec-butylbenzene, cymene, dipentene, methyl pyruvate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, methyl methoxypropionate, cyclopentanone, cyclohexanone, butyl acetate, gamma-butyrolactone, isoamyl acetate, chloroform, dichloromethane, 1,4-dioxane, hexyl alcohol, 2-heptanone, 、 and tetrahydrofuran.

[0036] In a specific embodiment of the present invention, the chemical liquid is a pre-wet liquid. The type of the pre-wet liquid is not particularly limited. Specific examples of the pre-wet liquid include at least one of cyclopentanone (CyPe), cyclohexanone (CyH), propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether (PGEE), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monopropyl ether (PGPE), and ethyl lactate (EL). In other embodiments, the chemical liquid may be a developer such as butyl acetate, or a rinse liquid such as 4-methyl-2-pentanol (MIBC).

[0037] <Impurities>

[0038] Impurities contained in the treatment object and / or chemical solution include metal impurities, particles, and others such as organic impurities and moisture.

[0039] <Metal impurities>

[0040] The most common metal impurities include heavy metals such as iron (Fe), aluminum (Al), chromium (Cr), and nickel (Ni), and ionic metals such as sodium (Na) and calcium (Ca). Depending on the type of metal, metal impurities can reduce oxide integrity, degrade MOS gate stacks, shorten device lifetime, etc. In the chemical solution produced by the processing method of the present invention, the total trace metal content is preferably within a predetermined range of 0 to 150 ppt by mass.

[0041] In the present invention, the metal impurities refer to metal impurities provided in a solid form (such as elemental metals or particulate metal-containing compounds).

[0042] In the present invention, the total trace metals in the chemical solution are measured by inductively coupled plasma mass spectrometry (ICP-MS). OWMP (on-wafer metal particles) are determined by inspecting the wafer with a combination of a laser-based inspection system and EDX (energy dispersive X-ray) inspection. The method for measuring total trace metals using ICP-MS and the method for measuring on-wafer metal particles (OWMP) using laser and EDX are as described in the following examples.

[0043] <particle> In the present invention, the objects to be counted that have a size of 0.03 μm or more are called “particles.” The number of “particles” in a liquid medium is counted by a light scattering liquid particle counter and is called LPC (liquid-borne particle count).

[0044] Examples of particles include dust, dirt, organic solids, and inorganic solids. The particles may also include impurities of colloidal metal atoms. The type of metal atom that is easily colloidalized is not particularly limited, but may include at least one metal atom selected from the group consisting of Na, K, Ca, Fe, Cu, Mg, Mn, Li, Al, Cr, Ni, Zn, and Pb. In the liquid medicine prepared by the liquid medicine manufacturing apparatus of the present invention, the total number of particles having a size of 0.03 μm or more is preferably within a predetermined range of 100 or less per 1 ml of the liquid medicine.

[0045] <Organic impurities>

[0046] Organic impurities refer to compounds other than the organic solvent that is the main component of the chemical solution, and organic matter contained in an amount of 5,000 mass ppm or less relative to the total mass of the chemical solution corresponds to organic impurities, but does not correspond to organic solvents.

[0047] Volatile organic compounds are present in the ambient air, even in clean rooms. Some organic impurities come from shipping and storage equipment, while others are present in the raw materials in the first place. Other examples of organic impurities include by-products produced when organic solvents are synthesized and / or unreacted reactants.

[0048] The total content of organic impurities in the chemical solution is not particularly limited. From the viewpoint of improving the manufacturing yield of semiconductor devices, the total content of organic impurities is preferably 0.001 to 5000 mass ppm, more preferably 0.003 to 2000 mass ppm, further preferably 0.005 to 1000 mass ppm, particularly preferably 0.008 to 500 mass ppm, and most preferably 0.01 to 100 mass ppm, based on the total mass of the chemical solution.

[0049] The content of organic impurities in the liquid drug can be measured by using a gas chromatography mass spectrometry (GCMS) device.

[0050] In the following, an embodiment of the present invention describes an exemplary method for treating a chemical liquid. The method for treating a chemical liquid includes performing a treatment step in at least a portion of a chemical liquid manufacturing apparatus that contacts the chemical liquid, whereby unwanted contaminants that may be extracted or leached into the chemical liquid from the portion of the manufacturing apparatus are reduced or eliminated. The treatment step is performed prior to the treatment of the chemical liquid performed by the chemical liquid manufacturing apparatus of the present invention. This allows the treated chemical liquid to be tightly controlled to meet or exceed ultra-high purity standards, with the number of particulate matter and the amount of metal impurities in the treated chemical liquid effectively controlled within desired ranges. Ultimately, the occurrence of residue and / or particle defects is suppressed, and the yield of semiconductor wafers is improved.

[0051] <How to handle chemicals>

[0052] While the method steps for treating a chemical fluid are depicted and described as a sequence of acts or events, it is understood that the depicted order of such acts or events is not to be construed in a limiting sense, and in addition, not all depicted processes or steps may be required to implement one or more embodiments of the present invention.

[0053] Figure 1A is a flow diagram of steps in an exemplary method for processing a chemical fluid according to some embodiments of the present invention. Figure 2 is a schematic diagram depicting an exemplary chemical fluid manufacturing apparatus adapted for a method for processing a chemical fluid according to some embodiments.

[0054] 1A and 2, a method for treating a chemical solution according to some embodiments of the present invention includes, in step 10, providing a chemical solution to produce a treated chemical solution. Chemical liquid manufacturing equipment 210 According to exemplary embodiments of the present invention, the number of unwanted particulate matter (particles) and the amount of metal impurities in the treated chemical solution are limited to within predetermined ranges. In some exemplary embodiments, Chemical liquid manufacturing equipment 210 includes at least one first purification system 110. In certain exemplary embodiments, Chemical liquid manufacturing equipment 210includes a second purification system 120 in addition to or instead of at least one first purification system 110.

[0055] 1A and 2, the first purification system 110 includes one or more filtration media 114 (purification means), each having a specific purification function (type or medium of filtration unit) and providing a specific process. For example, the purification system 110 may include at least one filtration media 114 (114a, 114b, or 114c) selected from a particle removal filter, an ion exchange membrane, and an ion adsorption membrane. Furthermore, the one or more filtration media 114 are high quality grade products commercially available from a supplier.

[0056] In certain exemplary embodiments, one or more filtration media 114 are each compartmentalized and housed in one or more housings 112. For example, the first purification system 110 may include at least one housing 112 selected from a first housing 112a, a second housing 112b, and a third housing 112c, where the at least one housing 112 contains and houses one or more units of the filtration media 114 therein. Alternatively, in the above example, the first purification system 110 may include only one housing 112 (either the first housing 112a, the second housing 112b, or the third housing 112c), or two housings 112 (any combination of two of the first housing 112a, the second housing 112b, and the third housing 112c), or three housings 112 (the first housing 112a, the second housing 112b, and the third housing 112c). It should be noted that the above examples are for illustrative purposes only, and the number of housings is not limited to the examples shown. In other exemplary embodiments, the first purification system 110 may include more housings, for example, 1, 2, 3, 6, or 10 or more, in addition to the first, second, and third housings (112a, 112b, 112c) described above. In alternative exemplary embodiments, there may be no separate housing 112, and the one or more filtration media 114 are configured to be non-compartmentalized in the first purification system 110. In yet other exemplary embodiments, the first purification system 110 may also include other purification modules (not shown) in addition to the one or more filtration media 114.

[0057] As shown in FIG. 2, the first housing 112a may include one or more units of the first filtration medium 114a, the second housing 112b may include one or more units of the second filtration medium 114b, and the third housing 112c may include one or more units of the third filtration medium 114c, where the first, second and third filtration media 114a, 114b, 114c may have different functions or performance, and each of the one or more units of the filtration media 114 (114a, 114b, 114c) contained in each selected housing (112a, 112b, 112c) has the same or similar purification function, physicochemical properties, pore size and / or construction material, etc. As an example, the first purification system 110 may include one or more particle removal filters, one or more ion exchange membranes, and one or more ion adsorption membranes housed in the first housing 112a, the second housing 112b, and the third housing 112c, respectively. In another example, the first purification system 110 may include one or more particle removal filters and one or more ion exchange membranes housed in the first housing 112a and the second housing 112b, respectively. In another example, the first purification system 110 may include one or more particle removal filters and one or more ion adsorption membranes housed in the first housing 112a and the second housing 112b, respectively. It should be noted that the above examples are for illustrative purposes only and are not intended to be limiting.

[0058] The number of units of filtration medium 114 (114a, 114b, 114c) housed in each selected housing 112 (112a, 112b, 112c) is not limited. In some embodiments, the number of units of filtration medium 114 housed in each selected housing 112 may range from 1 to 30, inclusive, such as 1, 2, 10, 15, 20, 30, or any number between any two of the aforementioned numbers of units. In alternative embodiments, the number of units of filtration medium 114 may be greater than 30. It should be noted that the number of units of filtration medium 114 housed in each selected housing 112 is not limited to the illustrated example.

[0059] 1A and 2, a method for treating a chemical solution may include, in step 20a: Chemical liquid manufacturing equipment 210 is processed by the first purification system 110. Chemical Solution 220 The first purification system 110 includes performing a treatment step with the treatment liquid in the first purification system 110 having one or more filtration media 114 before conveying the treatment liquid to the first purification system 110. In some exemplary embodiments, the treatment step can include a cleaning process to remove native impurities embedded in the filtration media 114. More specifically, one or more units of filtration media 114 (114a, 114b, 114c) housed in each selected housing 112 (112a, 112b, 112c) can be Cleaning solution 230 It should be noted that the process steps of the first purification system 110 are not limited thereto.

[0060] According to some exemplary embodiments of the present invention, the treatment step in step 20a may be performed by soaking the filtration media 114 (114a, 114b, 114c) in a treatment solution for a predetermined period of time. In yet other exemplary embodiments, the treatment step may involve a combination of washing and soaking to reduce the amount of wet particles in the filtration media 114 and improve treatment efficiency.

[0061] According to the present invention, the cleaning liquid used in the cleaning process is not particularly limited, and any known cleaning liquid can be used. For example, water and an organic solvent in which particulate matter (particles), metal impurities, and organic impurities have been sufficiently reduced may be used. In certain embodiments, the chemical liquid itself or a liquid obtained by diluting the chemical liquid can be used as the cleaning liquid. In some exemplary embodiments, the cleaning liquid is the same as at least one of the organic solvents contained in the chemical liquid to be treated, with the proviso that at least one of the organic solvents is a high-purity product containing only a small amount of impurities. As a standard for the cleaning liquid (30, 40) of the present invention, the content of iron (Fe) and calcium (Ca) in the cleaning liquid applied in the cleaning process is limited to about 10 ppb or less.

[0062] Examples of organic solvents used as the cleaning liquid of the present invention include, but are not limited to, alkylene glycol monoalkyl ether carboxylates, alkylene glycol monoalkyl ethers, lactic acid, alkyl esters, alkyl alcohols, alkyl alkoxypropionates, cyclic lactones (preferably having 4 to 10 carbon atoms), monoketone compounds which may have a ring (preferably having 4 to 10 carbon atoms), alkylene carbonates, alkoxyalkyl acetates, and alkyl pyruvates.

[0063] More specifically, examples of the cleaning solution include, but are not limited to, isopropanol, propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monoethyl ether (PGEE), propylene glycol monopropyl ether (PGPE), ethyl lactate (EL), dimethyl sulfoxide (DMSO), n-methylpyrrolidone (NMP), diethylene glycol (DEG), ethylene glycol (EG), dipropylene glycol (DPG), propylene glycol, propylene ethylene carbonate, propylene carbonate, sulfolane, cyclohexane, cyclohexanone (CyH), cycloheptanone (CyHe), cyclopentanone (CyPe), 2-heptanone, and γ-butyrolactone. Furthermore, two or more different types of these organic solvents may be mixed and used as a cleaning solution, or may be used without being mixed.

[0064] 1A and 2, the method of cleaning is not particularly limited. In some exemplary embodiments, the cleaning process includes flushing or rinsing with a large amount of liquid. More specifically, one or more units of filtration media 114 (114a, 114b, 114c) housed in each selected housing 112 (112a, 112b, 112c) are Cleaning solution 230 will be flushed.

[0065] In the case where the cleaning step includes flushing, a predetermined amount of Cleaning solution 230 is dispensed into a first housing of the selected housings 112 (112a, 112b, 112c) that are coupled together; Cleaning solution 230 The cleaning fluid is caused to flow or pass through the filtration media 114 in each selected housing 112 (112a, 112b, 112c) so that each unit of the filtration media 114 is in full contact with the cleaning fluid and any native impurities that may be clogged or embedded within the filtration media are removed. Cleaning solution 230 It is carried by. Cleaning solution 230 Then, the ionized water leaves the last enclosure (e.g., the third enclosure 112c) of the selected enclosures 112 and is collected in the waste tank 130. In the above exemplary embodiment, Cleaning solution 230 for processing Chemical Liquid Manufacturing Equipment 210 fart Chemical Solution 220 The first purification system 110 may be configured to deliver the first purifying agent to a first enclosure via a conduit separate from the conduit for delivering the first purifying agent. However, it should be noted that the above examples are for illustrative purposes only and are not intended to be limiting. In an alternative embodiment, Cleaning solution 230 and Chemical Solution 220 through the same conduit, Chemical liquid manufacturing equipment 210 The resulting mixture may be sent to a first purification system 110.

[0066] The amount of cleaning fluid used in the cleaning or flushing process is not particularly limited. A practical amount of cleaning fluid adapted for the cleaning or flushing process in some embodiments of the present invention may range from 5 to 500 gallons per enclosure 112 per cleaning cycle, inclusive. For example, the amount of cleaning fluid may be about 5, 10, 20, 50, 100, 200, 300, 400, 500 gallons per enclosure 112 per cleaning cycle, including any range between any two of the aforementioned amounts.

[0067] As an example, when approximately 10 gallons of cleaning solution are applied to wash or flush each housing 112 of the filtration media 114, and in a scenario in which a purification system 110 having three housings (112a, 112b, 112c) of filtration media 114 (114a, 114b, 114c) is being washed or flushed as illustrated in FIG. 2, a total of 30 gallons of cleaning solution may be applied. Cleaning solution 230 is dispensed into the first purification system 110 per cleaning cycle. More specifically, about 30 gallons of Cleaning solution 230 is dispensed into the first housing 112a. Cleaning solution 230Then, the filtration media (114a, 114b, 114c) in each housing (112a, 112b, 112c) moves forward from the first housing 112a to the second housing 112b, and finally is discharged from the third housing 112c to the discharge tank 130, thereby Cleaning solution 230 The device is flushed and cleaned with

[0068] It should be noted that the above examples are for illustrative purposes only, and the number of housings 112 of filtration media 114 to be treated or cleaned is not limited to the examples shown. In other exemplary embodiments, the number of housings 112 of filtration media 114 to be treated or cleaned may be, for example, 1, 2, 5, or 10, and the amount of cleaning fluid used may be, correspondingly, 10, 20, 50, or 100 gallons per cleaning cycle. Furthermore, the above exemplary amount of cleaning fluid per housing per cleaning cycle of 10 gallons is for illustrative purposes only and is not intended to be limiting. The amount of cleaning fluid per housing per cleaning cycle may vary depending on the source, type, and initial condition of the filtration media 114 (114a, 114b, 114c), for example, 30 gallons, 55 gallons, 150 gallons, or 400 gallons of cleaning fluid may be applied per housing per cleaning cycle. The initial condition of the filtration media 114 is, for example, the condition in which the filtration media 114 is obtained from the supplier.

[0069] The number of cleaning or flushing cycles performed is not particularly limited and may vary depending on the source, type, and initial condition of the filtration media 114 (114a, 114b, 114c). In certain embodiments of the invention, the cleaning or flushing of the filtration media 114 is a single step (1X) Chemical Solution 220After a single cleaning or flushing step is completed, the cleaning or flushing may be performed multiple cycles, e.g., two (2X), three (3X), four (4X), six (6X), or eight (8X) cycles, with a fresh batch of cleaning solution being used for each cycle. In the present invention, a "fresh batch of cleaning solution" means a cleaning solution that has not been previously used in a cleaning or flushing step, and the iron (Fe) and calcium (Ca) content in the cleaning solution is about 10 ppb or less.

[0070] For example, according to the above-mentioned example of applying 10 gallons of cleaning solution to wash or flush the filtration media 114 (114a, 114b, 114c) in each of the three housings 112 (112a, 112b, 112c), a total of 60 gallons (30+30) of cleaning solution is consumed in two cycles (2X) of cleaning or flushing processes. In this context, a fresh batch of 30 gallons of cleaning solution is used during the first cycle of cleaning or flushing, and another fresh batch of 30 gallons of cleaning solution is used during the second cycle of cleaning or flushing. It should be noted that the above examples are for illustrative purposes only, and the number of housings, the amount of cleaning solution applied per housing per cycle, and the number of cleaning cycles are not limited to the examples shown.

[0071] In other embodiments, to achieve the effect of multiple cycles of cleaning or flushing, the sum of the cleaning fluid intended for all cleaning cycles combined is collectively applied to clean or flush the filtration media 114 in the enclosures 112. For example, the two cycles of cleaning or flushing steps illustrated above may require a total of 60 gallons of cleaning fluid to clean or flush the filtration media 114 (114a, 114b, 114c) in each of the three enclosures 112 (112a, 112b, 112c). Cleaning solution 230 This is achieved by applying

[0072] Referring to Figure 2, Chemical Liquid Manufacturing Equipment 210may further include a second purification system 120 in direct or indirect communication with the first purification system 110, the second purification system 120 including one or more filtration media 124. In the exemplary embodiment as shown in Figure 2, the second purification system 120 is configured downstream of the first purification system 110. However, it should be noted that the relative configuration of the first purification system 110 and the second purification system 120 is not limited to the example shown above.

[0073] Similar to the first purification system 110, the one or more filtration media 124 in the second purification system 120 may each be compartmentalized and housed in one or more housings 122. For example, the second purification system 120 may include at least one housing 122 selected from a fourth housing 122a, a fifth housing 122b, and a sixth housing 122c, where the at least one housing 122 contains and houses one or more units of the filtration media 124 therein. Alternatively, according to the above example, the second purification system 120 may include one, two, or three housings 122. In other exemplary embodiments, the second purification system 120 may include more housings 122, for example, one, two, five, or ten or more, in addition to the fourth housing 122a, the fifth housing 122b, and the sixth housing 122c. Additionally, there may be no separate housing 122, and the one or more filtration media 124 may be configured to be non-compartmentalized in the second purification system 120. In yet other exemplary embodiments, the second purification system 120 may include other material processing modules, not shown, in addition to the one or more filtration media 124.

[0074] The fourth housing 122a may include one or more units of the fourth filtration medium 124a, the fifth housing 122b may include one or more units of the fifth filtration medium 124b, and the sixth housing 122c may include one or more units of the sixth filtration medium 124c, where the fourth filtration medium 124a, the fifth filtration medium 124b, and the sixth filtration medium 124c may have different functions or performance and provide different purification processes, and each of the one or more units of the filtration medium 124 (124a, 124b, 124c) contained in each selected housing 122 (122a, 122b, 122c) has the same or similar purification function, physicochemical properties, pore size and / or construction material, etc. In some exemplary embodiments, the second purification system 120 may include at least one filtration medium 124 (124a, 124b, 124c) selected from a particle removal filter, an ion exchange membrane, and an ion adsorption membrane. Chassis 122a and the three particle filters housed in the fifth Chassis 122b and three ion exchange membranes or three ion adsorption membranes housed in the fourth purification system 120. Chassis 122a and a fifth Chassis The one or more filtration media 124 may include another two, three, or four particle filters housed in the two housings 122a, 122b, where the particle filters in the two housings 122a, 122b differ in pore size and / or material of construction. Additionally, the one or more filtration media 124 are high quality products commercially available from a supplier.

[0075] The number of units of filtration medium 124 (124a, 124b, 124c) housed in each selected housing 122 (122a, 122b, 122c) is not limited. In some embodiments, the number of units of filtration medium 124 housed in each selected housing 122 may be in the range of 1 to 30, inclusive, for example, 1, 2, 10, 15, 20, 30, or any number between any two of the aforementioned numbers of units. In alternative embodiments, the number of units of filtration medium 124 may be more than 30. It should be noted that the number of units of filtration medium 124 housed in each selected housing 122 is not limited to the example shown.

[0076] Referring again to FIG. 1A, the method for treating a chemical solution includes, in step 20b, Chemical Liquid Manufacturing Equipment 210 Prior to treatment of the chemical fluid at the filtration system, a second purification system 120 having one or more filtration media 124 is used to perform a treatment step with the chemical fluid.

[0077] The principles of the treatment steps applied to the second purification system 120 are similar to those applied to the first purification system 110 exemplified in paragraphs

[0055] to

[0072] . For example, the treatment steps performed in the second purification system 120 may include a cleaning step. More specifically, in step 20b, one or more units of the filtration media 124 (124a, 124b, 124c) housed in each selected housing 122 (122a, 122b, 122c) of the second purification system 120 are washed with a cleaning liquid 40.

[0078] Further, in the context of the washing process including flushing, a predetermined amount of washing solution 40 is dispensed into a first housing of the selected housing 122 in the second purification system 120 to wash or flush one or more units of filtration media 124 (124a, 124b, 124c) contained in each selected housing 122 (122a, 122b, 122c) connected to each other in the second purification system 120. The washing solution 40 is caused to flow or pass through the filtration media 124 in each selected housing 122, so that each unit of the filtration media 124 is in full contact with the washing solution, and the washing solution 40 washes out the inherent impurities that are clogged or embedded in the filtration media 124. The washing solution 40 then leaves the last housing (e.g., the sixth housing 122c) of the selected housing 122 and is collected in the drain tank 150. It should be noted that the above exemplary process steps applied to the second purification system 120 are for illustrative purposes and are not intended to be limiting.

[0079] Still referring to FIG. 1A, after the process steps of the first purification system 110 in step 20a are completed and / or after the process steps of the second purification system 120 in step 20b are completed, Chemical Solution 220 The process is carried out in step 30 according to the present invention. Chemical Liquid Manufacturing Equipment 210 The treatment of the chemical solution in step 30 can be carried out, for example, by: Chemical Liquid Manufacturing Equipment 210 Using the post-treatment first purification system 110 and / or the post-treatment second purification system 120 installed in Chemical Solution 220 This includes carrying out a purification step.

[0080] According to some embodiments, the treatment of the first purification system 110 and the treatment of the second purification system 120 are performed independently and separately, but may be performed simultaneously or sequentially. More specifically, the type of treatment fluid, treatment conditions, amount of treatment fluid used, number of treatment cycles, treatment method (flushing, immersion, or both), etc., that are applied to the treatment of the filtration media 114 of the first purification system 110 and those that are applied to the filtration media 124 of the second purification system 120 are related to the source, type, condition, and respective temperature of the filtration media 114 and 124. Purification System 110 ,120 Selected enclosures processed in 112 and 122 may be identical, similar, or varied from one another depending on the number of

[0081] As an example, cyclohexanone may be used as the treatment fluid 30 for treating the filtration medium 114 of the first purification system 110 and as the treatment fluid 40 for treating the filtration medium 124 of the second purification system 120. However, the treatment conditions and number of treatment cycles designated for treating the filtration medium 114 may differ from the treatment conditions and number of treatment cycles designated for treating the filtration medium 124. Furthermore, the treatment of the first purification system 110 may be performed before, after, or simultaneously with the treatment of the second purification system 120. It is further understood that a new batch of cyclohexanone is applied to each of the first purification system 110 and the second purification system 120, and a new batch of cyclohexanone is applied for each treatment cycle for the treatment of each of the purification systems 110 and 120. It should be noted that the above examples are for illustrative purposes and are not intended to be limiting.

[0082] For most of the filtration media 114 and 124 and processing fluids applied in the treatment process, the treatment process is carried out at ambient conditions (room temperature and pressure). However, in some exemplary embodiments, the treatment conditions are a function of the filtration media (114, 124) and / or the processing fluid used to treat them. In certain exemplary implementations, the treatment conditions are controlled below or above ambient conditions. For example, cleaning or flushing of certain ion exchange or ion adsorption membranes is carried out below room temperature, such as below 80° F. or below 77° F., when certain cyclic aliphatic ketone organic solvents are used as the cleaning fluid. As an example, cleaning or flushing of ion exchange membranes is carried out below 70° F., when cyclohexanone (CyH) is applied as the cleaning fluid.

[0083] When the filtration media 114, 124 undergoes a cleaning or flushing process, the flow rate of the cleaning fluid flowing through or through the filtration media 114, 124 is Chemical Solution 220is typically controlled to less than the normal operating flow rate of about 10-12 gallons per minute when the cleaning fluid is being treated. For example, the flow rate of the cleaning fluid during a cleaning or flushing process may range from as low as about 1 gallon per minute to as high as about 10 gallons per minute, e.g., about 1, 2, 5, or 8 gallons per minute. Of course, these are merely examples and are not intended to be limiting. In other embodiments, the flow rate may be greater than 10 gallons per minute, e.g., 18-20 gallons per minute.

[0084] Further, according to some embodiments of the present invention as shown in FIG. 1A, the process includes: Chemical liquid manufacturing equipment 210 The process is performed in-situ for one or more units of filtration media (114, 124) in each selected housing (112, 122) configured in a purification system (110, 120) already installed in the purification system (110, 120). In an alternative embodiment, an offline processing step may be performed. The offline processing step as shown in FIG. 1B is substantially equivalent to the in-situ processing step described above, with the main difference being that the selected housings (112, 122) are each configured in a purification system (110, 120) already installed in the purification system (110, 120). 110 , 120 ) Chemical liquid manufacturing equipment 210 Prior to being installed in the filtration system, each selected housing (112, 122) having one or more units of filtration media (114, 124) contained therein undergoes a treatment process, as exemplified in paragraphs

[0060] -

[0072] and

[0077] -

[0079] above. More specifically, as shown in FIG. 1B, a treatment process is performed in step 10a on each selected housing (112) having one or more units of filtration media 114, and the treatment process may be the same or different for each selected housing (112). Similarly, a treatment process is performed in step 10b on each selected housing (122) having one or more units of filtration media 124, and the treatment process may be the same or different for each selected housing (122). After the processing steps in steps 10a and 10b are completed, the selected enclosures 112 are configured together as a post-processing first purification system 110, and the selected enclosures 122 are configured together as a post-processing second purification system 120, which are then combined in step 20. Chemical Liquid Manufacturing Equipment 210After that, Chemical Solution 220 The process of the present invention Chemical liquid manufacturing equipment 210 This is accomplished in step 30 by matching a post-treatment first purification system 110 and a post-treatment second purification system 120 configured within the system.

[0085] [Particle removal filter]

[0086] The particle removal process is a process for removing particles and / or metal impurities (solid metal impurities) from a processing object such as a chemical solution by using a particle removal filter. The particle removal filter is not particularly limited, and any well-known particle removal filter can be used.

[0087] The average pore size (pore diameter) of the filter is not particularly limited, but is suitably about 0.001 to 1.0 μm (1 nm to 1000 nm), preferably about 0.003 to 0.5 μm (3 nm to 500 nm), and most preferably about 0.005 to 0.1 μm (5 nm to 100 nm). Within this range, foreign matter such as impurities or aggregates contained in the refined product can be reliably removed while preventing clogging of the filter. In a specific embodiment of the present invention, the first purification The system 110 may include a particle removal filter (e.g., a microfiltration membrane having a pore size of 2 nm or more) that may range from 0.002 μm (2 nm) to about 1.0 μm (1000 nm) with an average pore size of at least 2 nm. When the target contains fine particles in addition to colloidal impurities containing metal atoms such as iron or aluminum, the target is filtered by using a filter having an average pore size of at least 50 nm to remove particles before filtering by using a filter having an average pore size of at least 20 nm or 15 nm to remove relatively fine particles. This improves the filtering efficiency and particle removal performance.

[0088] In some embodiments of the invention, the second purification system 120may include a particle removal filter having a pore size as small as 0.001 μm (1 nm) and may range from about 0.001 μm (1 nm) to about 0.015 μm (15 nm). purification The system 120 may include a UPE filter having a pore size of at least 1 nm. purification The system 120 may include a nylon or MPTFE filter having a pore size of about 5 nm, where the average pore size may refer to the filter manufacturer's nominal value.

[0089] Examples of materials for the filter used for particle removal include fluororesins such as polytetrafluoroethylene (PTFE), polyamide resins such as nylon, polyolefin resins (including high density and ultra-high molecular weight) such as polyethylene and polypropylene (PP), perfluoroalkoxy (PFA) resins, or modified polytetrafluoroethylene (MPTFE). In consideration of efficiently removing fine foreign matter such as impurities and / or aggregates contained in the chemical solution, the filter used for particle removal of the present invention is manufactured from at least one selected from the group consisting of nylon, polypropylene (including high density polypropylene), polyethylene, polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polyimide, and polyamide imide. A filter manufactured from the above material can effectively remove foreign matter having high polarity that is likely to cause residue defects and / or particle defects, and can efficiently reduce the content of metal components in the chemical solution.

[0090] The polyimide and / or polyamideimide may have at least one selected from the group consisting of a carboxyl group, a salt-type carboxyl group, and an -NH- bond. Fluororesin, polyimide, and / or polyamideimide are excellent in solvent resistance.

[0091] Commercial filters can be selected from a variety of filters available, including those manufactured by Pall Corporation, ADVANTEC Toyo Roshi Kaisha, Integris Japan Co., Ltd. (formerly Nihon Microlith Co., Ltd.), and Kitz Microfilter Co., Ltd. In addition, the polyimide "P-Nylon Filter (pore size 0.02 μm, critical surface tension 77 mN / m)" (Pall Corporation), the high-density polyethylene "PE Clean Filter (pore size 0.02 μm)" (Pall Corporation), the high-density polyethylene "PE Clean Filter (pore size 0.01 μm)" (Pall Corporation), and the ultra-high molecular weight polyethylene membrane "UPE (pore size 3 nm)" (Integris) can be used.

[0092] [Ion exchange resin membrane (ion exchange membrane)]

[0093] The ion exchange resin membrane used in this embodiment is not particularly limited, and a filter containing an ion exchange resin containing an appropriate ion exchange group fixed to the resin membrane may be used. Examples of such ion exchange resin membranes include strongly acidic cation exchange resins having cation exchange groups such as sulfonic acid groups chemically modified on the resin membrane, and examples of such ion exchange resin membranes include cellulose, diatomaceous earth, nylon (resin having amide groups), polyethylene, polypropylene, polystyrene, resins having imide groups, resins having amide groups and imide groups, fluororesins, or membranes having an integral structure of a particle removal membrane and an ion exchange resin membrane. Ion exchange resin membrane and High density polyethylene with particle removal membrane Including membrane A polyalkylene membrane with chemically modified ion exchange groups is preferred. Polyalkylene includes, for example, polyethylene and polypropylene, with polypropylene being preferred. A cation exchange group is preferred as the ion exchange group. The ion exchange resin membrane used in this embodiment may be a commercially available filter with metal ion removal function. These filters are selected based on ion exchange efficiency and have an estimated filter pore size of at least about 0.2 μm (200 nm).

[0094] [Ion adsorption film]

[0095] The ion adsorption membrane has a porous membrane material and has an ion exchange function. Such an ion adsorption membrane is not particularly limited as long as it has a pore size of 100 μm or less and has an ion exchange function. The material, type, etc. are not particularly limited. Examples of the material of the substrate constituting the ion adsorption membrane include, but are not limited to, film materials of microfiltration membranes such as cellulose, diatomaceous earth, nylon (resin having an amide group), polyethylene, polypropylene, and polystyrene, resins having imide groups, resins having amide groups and imide groups, fluororesins, high-density polyethylene resins, and membrane materials into which ion exchange functional groups have been introduced. Examples of the shape of the membrane material include pleats, flat membranes, hollow fiber types, and porous bodies described in JP-A-2003-112060. As the ion exchange groups introduced into the membrane material, it is preferable to use a combination of at least two of cation exchange groups, chelate exchange groups, and anion exchange groups in order to optimize the elution and selectivity of the components to be removed. Since the ion adsorption membrane is porous, it is also possible to remove some of the fine particles. In certain embodiments of the invention, the ion-adsorbing membrane is, for example, a nylon membrane having a pore size of at least 0.02 μm (20 nm).

[0096] [Example]

[0097] The present invention will be described in more detail with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, etc. described in the following examples can be appropriately changed within a certain range without departing from the gist of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited by the following examples.

[0098] The selection of filtration media 114 in the first purification system 110, the number of wash cycles, and the amount of wash solution applied to treat the selected filtration media were adjusted to obtain a treated wash solution having the composition in each sample at the end of each wash cycle. The filtration media used in the following experiments were high quality grade products obtained new from a supplier. In some experiments, multiple units of the filter were flushed once, but the data presented below has been mathematically normalized to a single unit.

[0099] <OWPC、OWMC、SP5>

[0100] Cleaning fluid samples were collected after each process and then inserted into a wafer coating tool. After the bare wafer was coated with the sample, the wafer was transferred to a laser-based inspection system for inspection. Using laser light, the laser-based inspection system detected, counted, and recorded the location and size of each particle on the wafer with a detection limit of 19 nm. More specifically, the count included particles having a size of 19 nm or greater. The data was used to create a wafer map and provide a total on-wafer particle count (OWPC), which includes all particles having a size of 1000 nm or less. SP5 is a subset of the OWPC that includes particles having a size between about 19 nm and about 23 nm.

[0101] The wafers were then transferred for inspection by EDX (energy dispersive X-ray). Each particle reported by the laser based inspection system was inspected by EDX (energy dispersive X-ray) to provide elemental information. Particles that gave any metal signal were counted as metal particles. The total number of particles with metal signatures were summed to be reported as OWMP (on-wafer metal particles) or OWMC (on-wafer metal count).

[0102] <Evaluation Results>

[0103] In Table 1, a flushing process according to the present invention was carried out on a first purification system containing an ultra-high MW polyethylene particle (UPE) removal filter having a pore size of 3 nm. The flushing solution used was cyclohexanone in an amount of about 10-50 gallons per flush, which was flushed or passed through the UPE filter at ambient temperature and inlet pressure up to 50 psig (pounds per square inch). Samples were collected at the end of each of the four flushing cycles (first flush, second flush, third flush, fourth flush). The OWPC, OWMC (or OWMP) and the number of selected metal elements in each sample were measured and the normalized data are summarized in Table 1. Figure 3 also graphically depicts the OWMC results.

[0104] Cleaning solution: Cyclohexanone Fluid volume per flush: 10 gallons Filter type: UPE (Ultra High MC Polyethylene) Pore ​​diameter: 3nm JPEG0007628075000001.jpg44133

[0105] As shown in Table 1 and Figure 3, the present treatment process was shown to achieve the desired benefit of significantly reducing the number of selected metal elements in the OMWC and UPE filters. The data also show that the effect of the treatment process was even more pronounced after the third flash. At the end of the fourth flash, the OWMC was four times lower than the OWMC after the first flash. Additionally, various selected metal elements such as Al, Fe, Mg, etc. were also significantly reduced by the end of the fourth flash.

[0106] Cleaning solution: Cyclohexanone Fluid volume per flush: 50-400 gallons Filter type: PTFE Pore ​​diameter: 7nm JPEG0007628075000002.jpg45133

[0107] In Table 2, a similar flushing process according to the present invention was carried out on a first purification system containing a high density polyethylene particulate removal filter having a pore size of 7 nm. The cleaning fluid used in this process was cyclohexanone, with the amount ranging from 50 to 400 gallons per flush. The cleaning fluid was flushed or passed through the HDPE filter at ambient temperature and inlet pressure up to 50 psig. Two separate but identical tests were performed for each flush cycle, and samples were collected at the end of each one of the four flush cycles (first flush, second flush, third flush, fourth flush) from each of the two tests. The OWPC, OWMC, and counts of selected metal elements in each sample were measured, and the normalized data are summarized in Table 2. Figure 3 also graphically represents the average OWMC results from the two tests.

[0108] The data summarized in Table 2 and depicted in Figure 3 indicate that the present treatment process was effective in improving the tested attributes of the PTFE filters. As shown in Table 2, the OWPC continued to decrease as the number of flushes increased. The data also reflects desirable improvements in the OWPC, OWMC, and number of selected metal elements after the third flush.

[0109] Cleaning solution: Cyclohexanone Filter type: HDPE (high density polyethylene) Pore ​​diameter: 2nm JPEG0007628075000003.jpg58132

[0110] In Table 3, the flushing process of the present invention was carried out on a purification system containing a HDPE (high density polyethylene) particulate removal filter with a pore size of 2 nm at ambient temperature and inlet pressures up to 50 psig. The cleaning solution used in this flushing process was cyclohexanone. Two separate tests were performed, with the amount of cleaning solution used during the second test being four times the amount used in the first test. Samples were collected at the end of each flush of the first and second tests. The OWPC, SP5, OWMC, and number of selected metal elements in each sample were measured, and the normalized data are summarized in Table 3.

[0111] The results shown in Table 3 confirm that the present treatment process achieved the desired benefit of reducing the counts of all selected metal elements in the OWPC, SP5, OWMC, and HDPE filters. The reduction was more pronounced after increasing the flush volume (or flush cycles) from about 30 gallons to about 125 gallons (or increasing from a single flush cycle to four flush cycles). Samples from the second test show that there was a 5-fold reduction in both the OWPC and SP5 counts and an 18-fold reduction in the OWMC counts when the volume of the wash solution (number of wash cycles) was increased four-fold. Typically, the number of particles having a size of about 19-23 nm from the pre-treated HDPE filters was greater than 10,000.

[0112] Cleaning solution: PGMEA (propylene glycol monomethyl ether acetate) Filter type: PTFE (polytetrafluoroethylene) Pore ​​diameter: 10nm JPEG0007628075000004.jpg58132

[0113] In Table 4, a similar flushing process was performed, except that PGMEA (propylene glycol monomethyl ether acetate) was used to flush the PTFE (polytetrafluoroethylene) particle filter with a pore size of 10 nm. Two separate tests were performed, and in the second test, the amount of cleaning solution used was eight times that used in the first test. Samples were collected at the end of each flush for the first and second tests. The number of selected metal elements in OWPC, SP5, OWMC, and each sample was measured, and the normalized data is summarized in Table 4.

[0114] The data presented in Table 4 shows that after the treatment process of the present invention was performed on the PTFE filter, the OWPC and OWMC This further confirms the significant effect of a significant reduction in OWPC. More specifically, after increasing the volume of cleaning solution from approximately 50 gallons to 400 gallons (or from a single flush cycle to eight flush cycles), the OWPC decreased significantly from over 500,000 to just over 1000. The data also show that after an eight-fold increase in cleaning solution, the OWMC and Fe counts decreased dramatically from saturated on the wafer to an order of magnitude (6 and 4, respectively).

[0115] JPEG0007628075000005.jpg46132

[0116] The data obtained in Table 5 was obtained using a treatment liquid (propylene glycol monomethyl ether acetate). The data in this table represents the effect of soaking the filtration media in the treatment liquid for a period of about 16 hours or more, followed by flushing with 50 kg of treatment liquid. More specifically, the filtration media was submerged in the treatment liquid overnight in an ambient environment. The filtration media was then placed in a filter housing and flushed with fresh treatment liquid. As can be immediately seen, soaking the filtration media prior to flushing provides a significant improvement in OWPC<31 (<31. nm bin size particles) and OWMC.

[0117] In some embodiments, the soaking step may be carried out for one or more periods, e.g., 2, 3, 4, or 5 periods, each period may be about 12-18 hours. More specifically, the filtration media is placed in a container and submerged in the same type of treatment liquid that will be used in the subsequent treatment step. At the end of each soaking step, the treatment liquid is drained and new treatment liquid is provided for the next soaking step. After the soaking step is completed, the treatment step is proceeded to flush the filtration media.

[0118] The collective results summarized in Tables 1-5 confirm that the present process achieves the desired benefit of significantly reducing OWPC and OWMC in various types of filtration media before they are applied to process chemicals. These data demonstrate that the present process prevents the introduction of unwanted contaminants that can result from ineffectively designed and improperly prepared process methods. Thus, the present process for processing chemicals provides a competitive advantage in producing ultra-high purity chemicals, avoiding the occurrence of defects in circuit patterns and semiconductor devices, and reducing maintenance and repair costs.

[0119] The foregoing outlines features of some embodiments so that those skilled in the art may better understand aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use this disclosure as a basis for designing or modifying other processes and structures to carry out the same purposes and / or achieve the same advantages as the embodiments presented herein. Those skilled in the art should also appreciate that such equivalent structures do not depart from the spirit and scope of the present disclosure, and that various modifications, substitutions, and alterations may be made without departing from the spirit and scope of the present disclosure.

Claims

1. 1. A method for treating a chemical solution, comprising: providing a system including at least one filtration medium selected from a filter, an ion exchange membrane, and an ion adsorption membrane; Executing a treatment process in the system configured within an apparatus using a treatment solution having a total concentration of iron (Fe) and calcium (Ca) of 10 ppb or less; performing a soaking step including soaking the at least one filtration medium in a treatment liquid that is the same type as the treatment liquid for a soaking period of at least 12 to 18 hours, with up to five soaking periods, prior to passing the treatment liquid through the system including the at least one filtration medium; treating the chemical solution in the system following the treatment step; Including, the system is installed in the apparatus after the processing steps have been performed; The system includes a plurality of housings in which the processing steps are performed, and the processing steps performed in each housing are different. method.

2. the treating step comprising passing the treatment liquid through the system including the at least one filtration medium; The method of claim 1.

3. The treatment liquid is the same as at least one organic solvent contained in the chemical liquid. The method of claim 1.

4. The process is carried out one or more times. The method of claim 1.

5. The treatment step is carried out in the system including at least two filtration media selected from the filter, the ion exchange membrane, and the ion adsorption membrane. The method of claim 1.

6. the treatment step is carried out in the system including the filter and one of the ion exchange membrane or the ion adsorption membrane; The method of claim 1.

7. The at least one filtration medium comprises a polytetrafluoroethylene (PTFE) filter having a pore size of 50 nm or less; The method of claim 1.

8. The at least one filtration medium comprises a polytetrafluoroethylene (PTFE) filter having a pore size of 10 nm or less; The method of claim 1.

9. The treatment of the chemical solution includes a purification step. The method of claim 1.

10. 1. A method for purifying a chemical solution, comprising: providing a first purification system including at least one first filtration medium selected from a first filter, a first ion exchange membrane, and a first ion adsorption membrane; performing a purification process on the chemical solution in the first purification system configured in the manufacturing apparatus; applying a first treatment solution to the at least one first filtration medium prior to carrying out the purification step, the first treatment solution having a sum of atomic iron (Fe) and calcium (Ca) concentrations of 10 ppb or less; performing a soaking step including soaking the at least one first filtration medium in a treatment liquid of the same type as the first treatment liquid for a soaking period of at least 12 to 18 hours, with up to five soaking periods, prior to passing the first treatment liquid through the first purification system including the at least one first filtration medium; providing a second purification system including at least one second filtration medium selected from a second filter, a second ion exchange membrane, and a second ion adsorption membrane; applying a second treatment solution to the at least one second filtration medium prior to carrying out the purification step, the second treatment solution having a sum of iron (Fe) and calcium (Ca) concentrations of 10 ppb or less; Including, the first purification system and the second purification system are installed in the manufacturing equipment after the step of applying the first processing liquid and the second processing liquid; The first purification system and the second purification system each include a plurality of housings in which the step of applying the first processing liquid and the second processing liquid is performed, and the step performed in each housing is different. method.

11. the step of applying the first processing fluid comprises flushing the first processing fluid into the first purification system. The method of claim 10.

12. the step of applying the second processing fluid comprises flushing the second processing fluid into the second purification system. The method of claim 10.

13. The purification step is performed on the chemical solution in the second purification system installed in the manufacturing apparatus. The method of claim 10.

14. the step of applying the first treatment liquid and the step of applying the second treatment liquid are each performed once. The method of claim 10.

15. the number of times the first treatment liquid is applied is different from the number of times the second treatment liquid is applied; The method of claim 10.

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