Impurity acquisition system, water quality inspection system, and liquid production / supply system

Abstract

This impurity acquisition system for acquiring a plurality of impurities in a liquid under inspection includes: a plurality of branch paths (30-1) to (30-3) branched in parallel from a flow path through which the liquid under inspection is passed; and a control device (100) for controlling a liquid passage condition of the liquid under inspection for each of the plurality of branch paths (30-1) to (30-3) on the basis of a background concentration measured in advance for each of the plurality of impurities.

Description

Impurity collection system, water quality testing system and liquid manufacturing and supply system

[0001] The present invention relates to an impurity acquisition system, a water quality inspection system, and a liquid manufacturing and supply system.

[0002] In a system for analyzing impurities in a test liquid using an adsorbent that adsorbs the impurities, a technique has been devised for switching between passing the test liquid through the adsorbent and passing an eluent that elutes the impurities adsorbed to the adsorbent through the adsorbent (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2022-120536

[0004] The above-described techniques have a problem in that when analyzing multiple types of impurities contained in a liquid to be inspected, it is difficult to perform efficient analysis according to the elements and concentration levels of the impurities.

[0005] An object of the present invention is to provide an impurity acquisition system, a water quality testing system, and a liquid manufacturing and supply system that can perform efficient analysis when analyzing multiple types of impurities.

[0006] The impurity acquisition system of the present invention is an impurity acquisition system that acquires multiple impurities in a liquid to be tested, and includes multiple branch paths branching in parallel from a flow path through which the liquid to be tested passes, and a control device that controls the flow conditions of the liquid to be tested for each of the multiple branch paths based on background concentrations that have been measured in advance for each of the multiple impurities.

[0007] Also, an impurity acquisition system for acquiring impurities in a test liquid includes a branch path branched from a flow path through which the test liquid flows, and a control device for controlling the flow conditions of the test liquid in the branch path based on a background concentration measured in advance for the impurity to be acquired.

[0008] The water quality testing system of the present invention is an impurity acquisition system for acquiring multiple impurities in a liquid to be tested, and includes: multiple branch paths branching in parallel from a flow path through which the liquid to be tested passes; a control device that controls the flow conditions of the liquid to be tested for each of the multiple branch paths based on background concentrations measured in advance for each of the multiple impurities; and an information processing device that analyzes the impurity concentrations in the liquid to be tested that have passed through the branch paths, and calculates the impurity concentrations in the liquid to be tested based on the impurity concentrations.

[0009] The liquid manufacturing and supply system of the present invention is an impurity acquisition system for acquiring multiple impurities in a liquid under test, the impurity acquisition system having multiple branch paths branching in parallel from a flow path through which the liquid under test passes, and a control device that controls the flow conditions of the liquid under test for each of the multiple branch paths based on background concentrations measured in advance for each of the multiple impurities; a water quality testing system including an information processing device that analyzes the impurity concentrations in the liquid under test passed through the branch paths and calculates the impurity concentrations in the liquid under test based on the impurity concentrations; a valve unit that controls the supply of the liquid under test from a liquid manufacturing and supply facility that produces and / or supplies the liquid under test to a use point where the liquid under test is used; and a second control device that controls the valve unit based on the impurity concentrations calculated by the information processing device.

[0010] In the present invention, when analyzing multiple types of impurities, the analysis can be carried out efficiently.

[0011] FIG. 1 is a diagram showing a first embodiment of an impurity acquisition system of the present invention. FIG. 2 is a diagram showing an example of components provided in the control device shown in FIG. 1. FIG. 3 is a diagram showing an example of information stored in the memory unit shown in FIG. 2. FIG. 4 is a diagram showing another example of information stored in the memory unit shown in FIG. 2. FIG. 5 is a flowchart for explaining an example of a control method in the control device shown in FIG. 1. FIG. 6 is a flowchart for explaining another example of a control method in the control device shown in FIG. 1. FIG. 7 is a time chart for explaining an example of control of the open / closed state of an on-off valve performed by the control device shown in FIG. 1. FIG. 8 is a diagram showing a second embodiment of an impurity acquisition system of the present invention. FIG. 9 is a diagram showing an example of a liquid manufacturing and supply system to which the impurity acquisition system of the present invention is applied. FIG. 10 is a diagram showing another example of a liquid manufacturing and supply system to which the impurity acquisition system of the present invention is applied.

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings.

[0013] 1 is a diagram showing a first embodiment of an impurity capture system according to the present invention. As shown in FIG. 1, the impurity capture system according to this embodiment includes a control device 100, ion exchanger units (ion exchangers) 200-1 to 200-3 that serve as adsorbents, on-off valves 300, 310-1 to 310-3, three-way valves 320-1 to 320-3, an eluent 400, and a pump 410. A branch path 20 branches off from a main path 10 that carries a test liquid from the ultrapure water production facility to a use point, and three branch paths 30-1 to 30-3 branch off from the branch path 20.

[0014] The ion exchanger units 200-1 to 200-3 adsorb impurities from a test liquid (ultrapure water) from an ultrapure water production facility. Here, the ultrapure water production facility produces ultrapure water to be supplied to a semiconductor cleaning device, which is a point of use, and supplies the ultrapure water to the semiconductor cleaning device. In the following description, this ultrapure water is the test liquid (test liquid), and the test liquid refers to the ultrapure water supplied from the ultrapure water production facility. The ion exchanger units 200-1 to 200-3 have ion adsorption capabilities (e.g., an ion adsorption membrane, a monolithic organic porous film, or an ion exchange resin). The substances adsorbed by the ion exchanger units 200-1 to 200-3 are impurities. These impurities include metal ions and impurities in the form of fine particles. In this embodiment, the functional groups of the ion exchanger units 200-1 to 200-3 are cations, anion exchange groups, or chelate compounds. The ion exchanger units 200-1 to 200-3 are provided in the branch paths 30-1 to 30-3, respectively.

[0015] The on-off valve 300 is an on-off valve that controls the flow of the test liquid passed through the main path 10 to the branch path 20. The on-off valve 310-1 is an on-off valve that controls the flow of the test liquid passed through the branch path 20 to the branch path 30-1. The on-off valve 310-2 is an on-off valve that controls the flow of the test liquid passed through the branch path 20 to the branch path 30-2. The on-off valve 310-3 is an on-off valve that controls the flow of the test liquid passed through the branch path 20 to the branch path 30-3. The opening degree of each of the on-off valves 310-1 to 310-3 can be adjusted.

[0016] The eluent 400 is an acidic or alkaline aqueous solution used to elute impurities adsorbed (concentrated) on the ion exchanger units 200-1 to 200-3. Examples of the eluent 400 include acidic aqueous solutions such as nitric acid, hydrochloric acid, and sulfuric acid, and alkaline aqueous solutions of organic alkalis such as trimethylhydroxyammonium and tetramethylammonium hydroxide (TMAH). The metal impurity concentration of the eluent 400 is less than 100 ppt. The degree of dilution of the eluent 400 is not particularly limited. The eluent 400 may be an aqueous solution diluted with the test liquid to be measured. The eluent 400 is contained in a container such as a bottle. The pump 410 pumps the eluent 400 from the container and sends it to the three-way valves 320-1 to 320-3. Gas pressure delivery may be used instead of the pump 410 to deliver the eluent 400.

[0017] The three-way valve 320-1 switches between passing either the test liquid via the on-off valve 310-1 or the eluent 400 sent from the pump 410 through the ion exchanger unit 200-1. Specifically, the three-way valve 320-1 passes either the test liquid from the on-off valve 310-1 or the eluent 400 pumped up by the pump 410 through the ion exchanger unit 200-1 in accordance with a control signal from the control device 100. The three-way valve 320-2 switches between passing either the test liquid via the on-off valve 310-2 or the eluent 400 sent from the pump 410 through the ion exchanger unit 200-2. Specifically, the three-way valve 320-2 passes either the test liquid from the on-off valve 310-2 or the eluent 400 pumped up by the pump 410 through the ion exchanger unit 200-2 in accordance with a control signal from the control device 100. The three-way valve 320-3 switches and controls the passage of either the test liquid via the on-off valve 310-3 or the eluent 400 sent from the pump 410 through the ion exchanger unit 200-3. Specifically, the three-way valve 320-3 passes either the test liquid from the on-off valve 310-3 or the eluent 400 pumped up by the pump 410 through the ion exchanger unit 200-3 in accordance with a control signal from the control device 100.

[0018] Furthermore, an analysis device 500 is provided in the impurity acquisition system shown in FIG. 1 to form a water quality testing system. The analysis device 500 analyzes the impurity concentration in the eluent that has passed through the ion exchanger units 200-1 to 200-3. The analysis device 500 is an information processing device that calculates the impurity concentration in the test liquid based on the analyzed impurity concentration. A specific example of the analysis device 500 is an ICP-MS. The analysis device 500 may display or manage the analysis results for the ion exchanger units 200-1 to 200-3 as the analysis results for one test liquid (ultrapure water).

[0019] The control device 100 controls the flow rate or flow (concentration) time of the test liquid through the ion exchange units 200-1 to 200-3, which are the conditions for passing the test liquid through the ion exchange units 200-1 to 200-3, based on the elements and concentration levels to be detected contained in the test liquid flowing through the branch paths 30-1 to 30-3.

[0020] Fig. 2 is a diagram showing an example of components included in the control device 100 shown in Fig. 1. As shown in Fig. 2, the control device 100 shown in Fig. 1 has an information input unit 110, an on-off valve adjusting unit 120, a timer 130, a control unit 140, and a storage unit 150. Note that Fig. 2 shows only the main components related to this embodiment among the components included in the control device 100 shown in Fig. 1.

[0021] The information input unit 110 inputs information to the control device 100 based on an operation from outside the control device 100. The method of inputting information is not particularly limited and may be an input method using a touch panel or an input method using input keys. The information input unit 110 outputs the input information to the control unit 140.

[0022] Based on instructions from the control unit 140, the on-off valve adjusting unit 120 adjusts the opening and closing and the opening degree of the on-off valves 300, 310-1 to 310-3 and the three-way valves 320-1 to 320-3.

[0023] The timer 130 is activated based on an instruction from the control unit 140. The timer 130 is activated based on an instruction from the control unit 140, and may issue a predetermined notification to the control unit 140 when the time notified by the control unit 140 is reached.

[0024] The control unit 140 stores the information input by the information input unit 110 in the memory unit 150. Specifically, for each of the branch paths 30-1 to 30-3 input by the information input unit 110, the element whose concentration is to be measured and the background concentration are associated and stored in the memory unit 150. The background concentration is the sum of the initial impurity concentrations of the ion exchanger units 200-1 to 200-3, the components constituting the device, and the eluent 400. The background concentration is a value measured in advance for each of the branch paths 30-1 to 30-3 and each element after the device is assembled. The control unit 140 determines the liquid flow conditions based on the elements and background concentrations. Examples of the liquid flow conditions include the liquid flow rate, the liquid flow time (concentration time), and the liquid flow volume. For example, the control unit 140 determines a longer liquid flow time for elements and branch paths with high background concentrations. The control unit 140 associates the determined liquid flow conditions and the analyte (element) with the element name and background concentration for each of the branch paths 30-1 to 30-3, and stores them in the memory unit 150. The control unit 140 controls the on-off valve adjuster 120 and the timer 130 using the association stored in the memory unit 150. For example, when the control unit 140 controls the liquid flow time through the branch path 30-1, the control unit 140 starts the timer 130 when starting the liquid flow, and instructs the on-off valve adjuster 120 to control the on-off valves 300 and 310-1 to an open state so that the test liquid flows into the branch path 30-1, and to control the three-way valve 320-1 so that the test liquid from the on-off valve 310-1 flows to the ion exchanger unit 200-1. Thereafter, when the time measured by the timer 130 reaches the liquid passage time stored in the memory unit 150, the control unit 140 instructs the on-off valve adjustment unit 120 to control the three-way valve 320-1 so that the eluent sent from the pump 410 flows into the ion exchanger unit 200-1. Furthermore, when the control unit 140 controls the liquid passage rate of the branch path 30-1, the control unit 140 instructs the on-off valve adjustment unit 120 to control the opening of the on-off valve 310-1 so that the liquid passage rate of the test liquid into the ion exchanger unit 200-1 becomes the liquid passage rate stored in the memory unit 150.

[0025] The storage unit 150 stores the information input by the information input unit 110 and the values ​​determined by the control unit 140 .

[0026] 3A is a diagram showing an example of information stored in the storage unit 150 shown in FIG. 2. As shown in FIG. 3A, the storage unit 150 shown in FIG. 2 stores, for each branch path, the background concentration, eluent volume, lower limit of quantification, concentration volume, liquid flow rate, liquid flow time, and the name of the target element assigned to the analysis path as the analysis target, all associated with each other. The background concentration, eluent volume, lower limit of quantification, and liquid flow rate are information input by the information input unit 110. The concentration volume V is a value calculated (determined) using Equation 1. Here, C ＢＬ is the background concentration (ng / L), and V Ｅ is the volume of eluent (L), and C ＬｏＱis the lower limit of quantitation (ng / L). The liquid flow time (or liquid flow rate) is calculated (determined) based on the liquid flow rate and the concentration calculated (determined) using (Equation 1). The background concentrations of each element are also measured in advance. For example, the following values ​​are measured: a background concentration of Na (sodium) of 5 (ng / L), a background concentration of potassium (K) of 5 (ng / L), a background concentration of calcium (Ca) of 15 (ng / L), a background concentration of iron (Fe) of 25 (ng / L), and a background concentration of copper (Cu) of 35 (ng / L). Multiple range thresholds indicating ranges of background concentrations according to the measured background concentrations are set for each branch path, and one of the multiple range thresholds is stored in the memory unit 150 as the background concentration for each branch path. The multiple set range thresholds are values ​​with a predetermined difference from each other, such as 10 (ng / L), 20 (ng / L), and 50 (ng / L). The measured background concentration of each element may also be stored in the memory unit 150. The background concentration of each element may be compared with the background concentration of each branch path shown in FIG. 3A, and the element whose background concentration satisfies the background concentration of each branch path shown in FIG. 3A is the element to be analyzed in that branch path. For example, among the background concentrations of each branch path stored in the memory unit 150, the analysis path whose value is closest to the background concentration of each element or whose difference from the background concentration of each element is equal to or less than a predetermined value is the analysis path in which the element is analyzed. By using this stored correspondence, the branch paths are assigned according to the background concentration of each element, allowing analysis to be performed according to the element. Note that values ​​calculated by another device as liquid flow conditions such as liquid flow rate and liquid flow time may be input using the information input unit 110 and stored in the memory unit 150.

[0027] FIG. 3(B) is a diagram showing another example of information stored in the storage unit 150 shown in FIG. 2. As shown in FIG. 3(B), the storage unit 150 shown in FIG. 2 stores, for each branch path, the background concentration of the analysis path, the eluent volume, the quantification lower limit, the concentration amount, the liquid flow rate, the liquid flow time, and the name of the target element assigned to the analysis path. The background concentration, the eluent volume, the quantification lower limit, and the liquid flow rate are information input by the information input unit 110. The quantification lower limit is a value set based on the background concentration of each element. The concentration amount V is a value calculated (determined) using the above-described (Equation 1). The correspondence shown in FIG. 3(B) differs from the correspondence shown in FIG. 3(A) in that the background concentrations of the branch paths 30-1 to 30-3 are the same, but the quantification lower limits are different. The branch paths are sorted according to the quantification lower limit. Therefore, analysis can be performed according to the concentration level of the target element.

[0028] A control method in the control device 100 shown in Fig. 1 will be described below. Fig. 4(A) is a flowchart for explaining an example of a control method in the control device 100 shown in Fig. 1. This example of a control method is a method performed when the correspondence shown in Fig. 3(A) is stored in the storage unit 150 shown in Fig. 2.

[0029] First, the control unit 140 reads from the storage unit 150 the element name, background concentration, eluent volume, and quantitation lower limit value associated with the branch path to be controlled (step S1). The control unit 140 calculates (determines) the condition (liquid flow rate or liquid flow time) based on the element name, background concentration, eluent volume, and quantitation lower limit value read from the storage unit 150 (step S2). The control unit 140 stores the calculated (determined) condition (liquid flow rate or liquid flow time) in the storage unit 150 in association with the element name and background concentration from which the calculation was based. When it is time to pass (concentrate) the test liquid through the ion exchanger units 200-1 to 200-3, the control unit 140 reads from the storage unit 150 the condition (liquid flow rate or liquid flow time) assigned to the branch path to be controlled. Then, the control unit 140 starts the timer 130 based on the conditions read out from the storage unit 150, and controls the on-off valves 300, 310-1 to 310-3, and 320-1 to 320-3 using the on-off valve adjustment unit 120 (step S3).

[0030] Fig. 4(B) is a flowchart for explaining another example of a control method in the control device 100 shown in Fig. 1. This example of the control method is a method performed when the correspondence shown in Fig. 3(B) is stored in the storage unit 150 shown in Fig. 2.

[0031] First, the control unit 140 reads from the storage unit 150 the element name, background concentration, eluent volume, and quantitation lower limit value associated with the branch path to be controlled (step S11). The control unit 140 calculates (determines) the condition (liquid flow rate or liquid flow time) based on the background concentration, eluent volume, and quantitation lower limit value read from the storage unit 150 (step S12). The control unit 140 stores the calculated (determined) condition (liquid flow rate or liquid flow time) in the storage unit 150 in association with the background concentration from which the calculation was based. When it is time to pass (concentrate) the test liquid through the ion exchanger units 200-1 to 200-3, the control unit 140 reads from the storage unit 150 the condition (liquid flow rate or liquid flow time) assigned to the branch path to be controlled. Then, the control unit 140 starts the timer 130 based on the conditions read out from the storage unit 150, and controls the on-off valves 300, 310-1 to 310-3, and 320-1 to 320-3 using the on-off valve adjustment unit 120 (step S13).

[0032] The background concentration, which is the sum of the elution concentration from the adsorbent (e.g., ion adsorption membrane, monolithic organic porous material, ion exchange resin) and the device components through which the test liquid passes and the initial concentration of the eluent, varies for each element whose concentration is being measured. Furthermore, the concentration time in the ion exchanger unit varies for each element whose concentration is being measured. Therefore, when impurities are obtained using multiple ion exchanger units, in a typical conventional system in which the test liquid is passed through the multiple ion exchanger units at the same concentration time (flow time) and flow rate, analysis is performed under conditions based on only some of the elements contained in the test liquid. These analytical conditions cannot be said to be optimal for other elements. Therefore, in a typical conventional system, it is difficult to efficiently analyze elements for which the conditions are not suitable.

[0033] In this embodiment, multiple branch paths 30-1 to 30-3 are provided, branching from a single branch path 20, for sampling the liquid to be tested (ultrapure water). The branched ultrapure water is passed through multiple ion exchanger units 200-1 to 200-3, respectively, for metal concentration. A measurement target element is assigned to each of the ion exchanger units 200-1 to 200-3, and the liquid flow (concentration process) is controlled under conditions corresponding to the element and the background concentration in the ion exchanger units 200-1 to 200-3. This allows the liquid flow (concentration), elution, recovery, and analysis (including metal concentration calculation) to be controlled under optimal conditions for each metal element assigned to each of the ion exchanger units 200-1 to 200-3, respectively, provided in the branch paths 30-1 to 30-3.

[0034] The control unit 140 may also control the open / close states of the on-off valves 310-1 to 310-3 and 320-1 to 320-3 so that the period during which the eluent 400 sent from the pump 410 is passed through the ion exchanger unit 200-1, the period during which the eluent 400 sent from the pump 410 is passed through the ion exchanger unit 200-2, and the period during which the eluent 400 sent from the pump 410 is passed through the ion exchanger unit 200-3 do not overlap with each other. In addition, the control unit 140 may control the open / close states of the on-off valves 310-1 to 310-3 and 320-1 to 320-3 so that the timing at which the passage of the test liquid to the ion exchanger unit 200-1 via the on-off valve 310-1 starts / ends, the timing at which the passage of the test liquid to the ion exchanger unit 200-2 via the on-off valve 310-2 starts / ends, and the timing at which the passage of the test liquid to the ion exchanger unit 200-3 via the on-off valve 310-3 starts / ends are all different from each other, in conjunction with controlling the periods at which the eluent is passed through each of the ion exchanger units 200-1 to 200-3 so that they do not overlap with each other.

[0035] FIG. 5 is a time chart illustrating an example of control of the on-off valves 310-1 to 310-3 and 320-1 to 320-3 by the control device 100 shown in FIG. A concentration step and an elution step are sequentially repeated in each of the branch path 30-1 including the ion exchanger unit 200-1, the branch path 30-2 including the ion exchanger unit 200-2, and the branch path 30-3 including the ion exchanger unit 200-3. While FIG. 5 only illustrates the concentration step and the elution step, other steps, such as a cleaning step, may also be performed. The control device 100 controls the on-off valves 310-1 to 310-3 and 320-1 to 320-3 so that the timings of the elution steps, in which the eluent is passed through each of the ion exchanger units 200-1 to 200-3, do not overlap with each other. In this embodiment, an example in which three ion exchanger units 200-1 to 200-3 are arranged in parallel to one another has been described, but the number of ion exchanger units is not limited to this.

[0036] In this way, multiple systems for analyzing the test liquid are provided in parallel, and the timing of the elution process between the systems is controlled so that the systems do not overlap. This allows the concentration process to be performed continuously, and therefore test results can be obtained continuously. (Second embodiment)

[0037] FIG. 6 is a diagram showing a second embodiment of the impurity acquisition system of the present invention. As shown in FIG. 6, the impurity acquisition system of this embodiment includes a branch path 30-4 instead of the branch path 30-3 of the impurity acquisition system of the first embodiment shown in FIG. 1. The branch path 30-4 is provided with an on-off valve 310-4. The on-off valve 310-4 is an on-off valve that controls the flow of the test liquid passed through the branch path 20 to the branch path 30-4. The branch path 30-4 does not include an ion exchanger unit like the ion exchanger units 200-1 and 200-2 provided in the branch paths 30-1 and 30-2, respectively. Therefore, the branch path 30-4 is a path for analyzing elements that cannot be concentrated or do not require concentration for analysis.

[0038] The test liquid passed through the branch path 30-4, which is not provided with an ion exchanger unit, is analyzed by the analyzer 500. The timing at which the analyzer 500 analyzes the impurities concentrated and eluted in the ion exchanger units 200-1 and 200-2 provided in the branch paths 30-1 and 30-2, respectively, corresponds to the calculated liquid flow rate and liquid flow time, as described in the first embodiment. The analyzer 500 analyzes the test liquid passed through the branch path 30-4 at a time other than the time at which the analyzer 500 analyzes the impurities concentrated and eluted in the ion exchanger units 200-1 and 200-2. This allows the analyzer 500 to be used efficiently and to perform continuous analyses in a short period of time. Furthermore, analyses can be performed over a wide range of analytical sensitivity.

[0039] Thus, in this embodiment, multiple branch paths 30-1, 30-2, and 30-4 are provided, branching from a single branch path 20, for sampling the liquid to be tested (ultrapure water). The branched ultrapure water is passed through multiple ion exchanger units 200-1 and 200-2 provided in each of the multiple branch paths 30-1 and 30-2, respectively, to concentrate metals. A measurement target element is assigned to each of the ion exchanger units 200-1 and 200-2, and the liquid flow (concentration process) is controlled under conditions corresponding to the element and the background concentration in the ion exchanger units 200-1 and 200-2. This allows the liquid flow (concentration), elution, recovery, and analysis (including metal concentration calculation) to be controlled under optimal conditions for each metal element assigned to each of the ion exchanger units 200-1 and 200-2 provided in each of the branch paths 30-1 and 30-2. The impurities concentrated and eluted in each of these ion exchanger units 200-1 and 200-2 are analyzed by an analyzer 500. The test liquid is also passed through the branch path 30-4, which is not provided with an ion exchanger unit, and the test liquid that has passed through the branch path 30-4 is analyzed by the analysis device 500. The branch path 30-4 is not provided with an ion exchanger unit. Therefore, the test liquid that has passed through the branch path 30-4 can be analyzed by the analysis device 500 at times other than when the analysis device 500 is analyzing the impurities that have been concentrated and eluted in the ion exchanger units 200-1 and 200-2.

[0040] The present invention can also be applied to a configuration in which there is only one branch path branching off from the main path 10. When there is only one branch path branching off from the main path 10, the following background concentrations are used to control the liquid flow conditions for the branch path when determining the liquid flow conditions for the branch path. When a single branch path is used to acquire the concentration of a specific impurity element, the control device 100 controls the liquid flow conditions using the background concentration of the element. When a single branch path is used to acquire the concentrations of multiple impurity elements, if there is no difference between the background concentrations of the multiple impurity elements, the control device 100 controls the liquid flow conditions using the background concentration with no difference. When a single branch path is used to acquire the concentrations of multiple impurity elements, if there is a difference between the background concentrations of the multiple impurity elements, the control device 100 controls the liquid flow conditions using the background concentration with the highest concentration value among the background concentrations.

[0041] The following describes an embodiment in which the above-described impurity acquisition system is used. FIG. 7 is a diagram showing an example of a liquid manufacturing and supply system to which the impurity acquisition system of the present invention is applied. The embodiment shown in FIG. 7 is a system in which ultrapure water is supplied to a semiconductor cleaning device (point of use) via a non-regenerative ion exchange device CP1000 and an ultrafiltration device UF1100 in an ultrapure water production facility. The ultrapure water (water to be tested) supplied to the CP1000 is supplied from a liquid manufacturing and supply facility installed upstream. The liquid manufacturing and supply facility is also a facility for producing ultrapure water. The dashed lines in FIG. 7 indicate the water flow path or the path of a control signal for testing the water quality of the ultrapure water to be tested.

[0042] There are two flow paths through which ultrapure water is supplied to the semiconductor cleaning apparatus. One of the flow paths is provided with an impurity removal unit 1200, and the ultrapure water is supplied to the semiconductor cleaning apparatus via the impurity removal unit 1200. An on-off valve 2000 is provided between the CP 1000 and the UF 1100. An on-off valve 2300 is provided to control the recovery of ultrapure water from the CP 1000 to the ultrapure water recovery tank. An on-off valve 2400 is provided to control the recovery of ultrapure water from the UF 1100 to the ultrapure water recovery tank. On-off valves 2100 and 2200 are provided on each of the two flow paths for supplying ultrapure water to the semiconductor cleaning apparatus.

[0043] The concentration / elution / recovery device 1300 corresponds to the impurity acquisition system shown in FIGS. 1 and 5. The ultrapure water from the CP 1000 or the ultrapure water from the UF 1100, which is the water to be tested, is subjected to the processing described in the first and second embodiments. The ICP-MS 1400 corresponds to the analysis device 500 shown in FIGS. 1 and 5. The ICP-MS 1400 is an apparatus (information processing device) that analyzes the impurity concentration in the acquired eluent and calculates the impurity concentration in the water to be tested based on the analyzed impurity concentration. The ICP-MS 1400 is equipped with an information processing function for calculating concentration. The concentration / elution / recovery device 1300 and the ICP-MS 1400 constitute a water quality testing system. The control device 1500 is a second control device that controls the opening and closing of the on-off valves 2000, 2100, 2200, 2300, and 2400 based on the impurity concentration calculated by the ICP-MS 1400.

[0044] If the impurity concentration calculated by ICP-MS 1400 for the outlet water of CP 1000 exceeds a preset concentration threshold, control device 1500 controls on-off valve 2000 to a closed state. At this time, control device 1500 controls on-off valve 2300 to an open state. Furthermore, if the impurity concentration calculated by ICP-MS 1400 for the outlet water of CP 1000 is equal to or lower than the concentration threshold, control device 1500 opens on-off valve 2000. At this time, control device 1500 closes on-off valve 2300. Furthermore, if the impurity concentration calculated by ICP-MS 1400 for the outlet water of UF 1100 exceeds a preset concentration threshold, control device 1500 controls on-off valves 2100 and 2200 to a closed state. At this time, control device 1500 controls on-off valve 2400 to an open state. Furthermore, when the impurity concentration calculated by ICP-MS 1400 for the outlet water of UF 1100 is equal to or lower than the concentration threshold, control device 1500 opens on-off valves 2100 and 2200. At this time, control device 1500 controls on-off valve 2400 to a closed state. Note that control device 1500 may control on-off valve 2100 to an open state when the impurity concentration calculated by ICP-MS 1400 for the outlet water of UF 1100 is equal to or lower than a first concentration threshold, control on-off valve 2200 to an open state and control on-off valve 2100 to a closed state when the impurity concentration calculated by ICP-MS 1400 exceeds the first concentration threshold and is equal to or lower than a second concentration threshold, and control on-off valves 2100 and 2200 to a closed state when the impurity concentration calculated by ICP-MS 1400 exceeds the second concentration threshold. This is because even if the impurity concentration in the flow path in which the impurity removal unit 1200 is installed is relatively high, the impurities contained in the ultrapure water are removed by the impurity removal unit 1200, thereby reducing the impurity concentration in the ultrapure water supplied to the semiconductor cleaning device.

[0045] FIG. 8 is a diagram showing another example of a liquid manufacturing and supply system to which the impurity acquisition system of the present invention is applied. In the application example shown in FIG. 8, the CP1000, UF1100, concentration / elution / recovery device 1300, ICP-MS 1400, control device 1500, and on-off valve 2400 are the same as those shown in FIG. 7. Ultrapure water, which is the outlet water from the UF1100, is distributed into multiple flow paths and supplied to multiple semiconductor cleaning devices connected to each flow path. Each of the multiple flow paths branches into a flow path to the concentration / elution / recovery device 1300. The ultrapure water flowing through each of the branched flow paths is treated as test water in the concentration / elution / recovery device 1300, as described in the first and second embodiments. The flow path through which the ultrapure water flowing is to be treated is selected by the control device 1500 controlling the opening and closing of on-off valves 2500-1 to 2500-4 provided in each branch path. Similarly to the process described above, the control device 1500 controls the opening and closing of on-off valves 2100-1 to 2100-4 provided in each flow path based on the impurity concentration calculated by the ICP-MS 1400. The control device 1500 may have a threshold value corresponding to each of the multiple semiconductor cleaning devices, and may control the opening and closing of on-off valves 2100-1 to 2100-4 based on a comparison between the impurity concentration calculated by the ICP-MS 1400 and the threshold value corresponding to each semiconductor cleaning device.

[0046] In this way, if the concentration of impurities contained in the ultrapure water exceeds a predetermined concentration threshold, the on-off valve is controlled to prevent the supply of ultrapure water to the semiconductor cleaning equipment. This prevents contamination of semiconductor devices and components within the ultrapure water facility. The liquid (water) to be measured is not limited to ultrapure water; it may also be a chemical solution such as IPA (isopropyl alcohol), PGMA (polyglycerol methacrylate), or PGMEA (propylene glycol monomethyl ether acetate). While the embodiment using a bottle to collect the eluent has been described, the collected eluent may also be directly sprayed into an analytical device for quantitative analysis. The concentration of metal impurities measured by this impurity collection system is not particularly limited, but is desirably 100 ng / L or less, preferably 1 ng / L or less, and more preferably 0.1 ng / L or less.

[0047] Although the above description has been given by allocating each function (process) to each component, this allocation is not limited to the above. Furthermore, the configuration of the components is also not limited to the above-described embodiments, which are merely examples. Furthermore, each embodiment may be combined.

[0048] Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

[0049] This application claims priority based on Japanese Patent Application No. 2024-116933, filed on July 22, 2024, the disclosure of which is incorporated herein in its entirety by reference.

[0050] 10 Main path 20, 30-1 to 30-4 Branch paths 100, 1500 Control device 110 Information input unit 120 On-off valve adjustment unit 130 Timer 140 Control unit 150 Memory unit 200-1 to 200-3 Ion exchanger unit 300, 310-1 to 310-4, 2000, 2100, 2100-1 to 2100-4, 2200, 2300, 2400, 2500-1 to 2500-4 On-off valve 320-1 to 320-3 Three-way valve 400 Eluent 410 Pump 500 Analytical device 1000 CP 1100 UF 1200 Impurity removal unit 1300 Concentration / elution / recovery device 1400 ICP-MS

Claims

1. An impurity acquisition system for acquiring a plurality of impurities in a liquid to be tested, comprising: a plurality of branch paths branching in parallel from a flow path through which the liquid to be tested passes; and a control device that controls the flow conditions of the liquid to be tested for each of the plurality of branch paths based on background concentrations measured in advance for each of the plurality of impurities.

2. An impurity collection system as described in claim 1, wherein an adsorbent that adsorbs impurities in the test liquid is disposed in each of the multiple branch paths, and the control device controls the amount of test liquid passing through each of the multiple adsorbents based on the background concentrations of the multiple impurities.

3. An impurity acquisition system as claimed in claim 1 or claim 2, wherein the control device sets a plurality of range thresholds indicating ranges of background concentrations according to the background concentrations of the plurality of impurities, and controls the flow conditions of the liquid to be tested for each of the plurality of branch paths based on the plurality of set range thresholds.

4. An impurity acquisition system as described in claim 1 or claim 2, wherein the control device sets quantitative lower limit values ​​for the plurality of impurities according to the background concentrations of each of the plurality of impurities, and controls the flow conditions of the liquid to be tested for each of the plurality of branch paths based on the quantitative lower limit values.

5. An impurity collection system according to claim 1 or 2, wherein the control device uses the flow rate of the test liquid through the plurality of branch paths as the liquid flow condition.

6. An impurity collection system according to claim 1 or 2, wherein the control device uses the time for which the test liquid is passed through the plurality of branch paths as the liquid passing condition.

7. An impurity acquisition system for acquiring impurities in a liquid to be tested, comprising: a branch path branching off from a flow path through which the liquid to be tested passes; and a control device for controlling the conditions under which the liquid to be tested passes through the branch path based on a background concentration of the impurity to be acquired that has been measured in advance.

8. A water quality testing system comprising: the impurity acquisition system described in claim 1; and an information processing device that analyzes the impurity concentration in the test liquid passed through the branch path and calculates the impurity concentration in the test liquid based on the impurity concentration.

9. A liquid manufacturing and supply system comprising: the water quality testing system described in claim 8; a valve unit that controls the supply of the liquid to be tested from a liquid manufacturing and supply facility that performs at least one of the manufacturing and supply of the liquid to be tested to a use point that uses the liquid; and a second control device that controls the valve unit based on the impurity concentration calculated by the information processing device.

Images