Water quality management method, information processing device and information processing system

Abstract

To enable the analysis of traces of particulates in the water to be analyzed to be executed later and facilitate execution of failure analysis.SOLUTION: Provided is a water quality management method for performing at least one of the quantitative analysis and the qualitative analysis of particulates included in the water to be analyzed. This method includes: a step for connecting a filtration device 20 where a particulate capture membrane 22 for capturing particulates is provided to a circulation pipe 11 in which the water to be analyzed flows; a step for flowing the water to be analyzed from the circulation pipe 11 to the particulate capture membrane 22 attached to the filtration device 20 over a prescribed period and causing the particulates included in the water to be analyzed to be captured as a particulate captured membrane sample; and a step for performing, at discretionary timing, at least one of the quantitative analysis and the qualitative analysis of the particulate captured membrane sample for the water circulation period concerned.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a water quality control method for controlling the concentration of particles in ultrapure water, and in particular to a water quality control method for quantifying trace amounts of particles present in ultrapure water, an information processing device used in this water quality control method, and an information processing system using these. [Background technology]

[0002] Ultrapure water is generally produced by treating water to be treated, such as river water, groundwater, or industrial water, in a pretreatment process to remove most of the suspended solids and organic matter in the water to produce pretreated water, and then sequentially treating this pretreated water in a primary pure water production system and a secondary pure water production system (subsystem). The produced ultrapure water is supplied to points of use, such as in semiconductor device manufacturing factories, where wafers are washed. Ultrapure water is also widely used in pharmaceutical manufacturing processes. The terms "pure water" and "ultrapure water" are generally not clearly defined, but in this specification, high-purity water generally described as "pure water" or "ultrapure water" is collectively referred to as "ultrapure water."

[0003] Ultrapure water is so pure that it is difficult to quantify the impurities contained in it, but it does not contain any impurities. The impact of the ultratrace components contained in ultrapure water on products such as semiconductor devices becomes more significant as the integration density of the devices increases. For this reason, the need for ultrapure water with even higher purity than conventional ultrapure water is being considered.

[0004] In semiconductor device manufacturing plants, ultrapure water produced in subsystems is supplied to use points via piping, which can be hundreds of meters long. This means that even small amounts of impurities, such as particles and metal ions, can get into the ultrapure water and adversely affect the characteristics of the semiconductor devices being manufactured. Particles, in particular, can directly affect yield by causing defects such as pattern defects, broken wires, and reduced dielectric strength. Therefore, strict control of both particle size and concentration is required. Recently, there has been a demand to keep particle concentrations below a specified value. The same is true for ultrapure water used in pharmaceutical manufacturing.

[0005] Direct microscopy is known as a method for detecting particles in ultrapure water (see, for example, Non-Patent Document 1). According to this method, pure or ultrapure water is filtered through a membrane filter, trapping particles on the membrane, and the trapped particles are then detected using an optical microscope or a scanning electron microscope. By using a membrane filter with a pore size smaller than the particle size of the target particle, even small particles can be detected. However, to ensure reliable detection, it is desirable to trap the same number of particles as or more than the number of particles contained in the membrane itself. To achieve this, a sufficient amount of pure or ultrapure water must be passed through the membrane filter. Furthermore, the smaller the particle size of the target particle, the smaller the pore size of the membrane filter required to trap the particle, resulting in increased pressure loss across the membrane filter. For these reasons, detecting small particles requires a long filtration time.

[0006] When detecting particles using direct microscopy, a method of filtering pure water or ultrapure water using a centrifugal filter is known (see, for example, Patent Documents 1 and 2). The pure water or ultrapure water is pressurized by centrifugal force, increasing the flow rate of the pure water or ultrapure water passing through the filtration membrane. This reduces the time required for filtration. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Utility Model Application Publication No. 4-136550 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-115810 [Non-patent literature]

[0008] [Non-Patent Document 1] Japanese Industrial Standard JIS K 0554-1995 "Method for measuring particles in ultrapure water" Summary of the Invention [Problem to be solved by the invention]

[0009] The direct microscopic method described in Patent Documents 1 and 2 was improved for the purpose of measuring trace (micro) particles contained in ultrapure water, and plays an important role in determining whether the quality of ultrapure water meets its specifications immediately after installation of an ultrapure water production system or after maintenance. When a defect is discovered in a product manufactured using ultrapure water, various possible factors must be analyzed to determine the cause of the defect. As part of this analysis, the possibility of an increase in the number of particles in the ultrapure water is considered, and particle analysis of the ultrapure water being used is performed using the direct microscopic method. In this case, even if particles contained in the ultrapure water are the cause of the defect, a considerable amount of time typically passes between the occurrence of the event that caused the defect and the analysis. As a result, the particles may no longer be present in the ultrapure water at the time of investigation, and the cause may remain unknown despite the considerable time and effort spent on the investigation.

[0010] The object of the present invention is to provide a water quality control method that enables the analysis of trace particles in the water being analyzed after the fact, making it easy to carry out defect analysis, an information processing device used in this water quality control method, and an information processing system that uses these. [Means for solving the problem]

[0011] The water quality control method of the present invention comprises: A water quality control method for performing at least one of quantitative analysis and qualitative analysis of particulates contained in analysis target water, a step of attaching a particle capture membrane for capturing the particles to a filtration device connected to a flow pipe through which the water to be analyzed flows; a step of passing the water to be analyzed through the flow pipe through the particle capture membrane attached to the filtration device for a predetermined period of time to capture particles contained in the water to be analyzed, thereby obtaining a particle capture membrane sample; a step of performing at least one of quantitative analysis and qualitative analysis of the microparticle capture membrane sample during the target water flow period at an arbitrary timing; It has.

[0012] The information processing device of the present invention comprises: an input unit that inputs input information based on an operation received from outside; a database that stores period information indicating the time period during which a particle capture membrane that captures particles in the analysis target water when the analysis target water is passed through the flow pipe and that corresponds to capture membrane identification information uniquely assigned to the particle capture membrane; a search unit that searches the database for the capture membrane identification information based on date and time information included in the input information input by the input unit; and an output unit that outputs the trapping membrane identification information retrieved by the retrieval unit.

[0013] The information processing system of the present invention comprises: The system includes a filtering device, an integrating flow meter, an analyzer, and an information processing device, The filtration device is a microparticle capture membrane that is detachably provided from the filtration device and captures microparticles in the analysis target water when the analysis target water passes through the membrane; The integrating flow meter is a filter disposed downstream of the filtration device in the direction of flow of the target water, and measuring an integrated value of the amount of water passing through the microparticle capture membrane; The information processing device includes: an input unit that inputs input information based on an operation received from outside; a database that stores period information indicating the time period during which the particle capture membrane was attached to the flow pipe through which the target water flows, in association with capture membrane identification information uniquely assigned to the particle capture membrane; a search unit that searches the database for the capture membrane identification information based on date and time information included in the input information input by the input unit; an output unit that outputs the capture membrane identification information retrieved by the retrieval unit; The analysis device performing at least one of quantitative analysis and qualitative analysis on the particle trapping membrane to which the trapping membrane identification information output by the output unit has been assigned; The output unit outputs information to be provided based on the results of the analysis performed by the analysis device. [Effects of the Invention]

[0014] According to the present invention, analysis of minute amounts of particles in the water to be analyzed can be carried out after the fact, making it easier to carry out defect analysis. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram showing a filtration device according to an embodiment of the present invention; [Figure 2] 1 is a flowchart illustrating a water quality management method. [Figure 3] FIG. 1 is a diagram illustrating an example of a location where a filtration device is connected in a factory that has a process that uses ultrapure water. [Figure 4] 2 is a diagram showing a first example of an information processing system using the filtering device shown in FIG. 1. FIG. [Figure 5] FIG. 5 is a diagram illustrating an example of an internal configuration of the information processing device illustrated in FIG. [Figure 6] FIG. 6 is a diagram showing an example of the association between period information and trapping membrane identification information stored in the database shown in FIG. 5. [Figure 7]FIG. 6 is a diagram showing an example of the association between installation information and capture film identification information stored in the database shown in FIG. 5. [Figure 8] 5 is a flowchart illustrating an example of processing in a filtering device in an information processing method in the information processing system shown in FIG. 4. [Figure 9] 5 is a flowchart illustrating an example of a search process in the information processing device, part of an information processing method in the information processing system shown in FIG. 4. [Figure 10] 1. FIG. 4 is a diagram showing a second example of an information processing system using the filtering device shown in FIG. [Figure 11] 11 is a diagram illustrating an example of the internal configuration of the information processing device illustrated in FIG. [Figure 12] 11 is a sequence diagram illustrating an example of an information processing method in the information processing system shown in FIG. [Figure 13] 13 is a flowchart illustrating an example of detailed processing of step S4 described with reference to the sequence diagram shown in FIG. 12. [Figure 14] 13 is a flowchart illustrating an example of detailed processing of step S8 described with reference to the sequence diagram shown in FIG. 12. DETAILED DESCRIPTION OF THE INVENTION

[0016] Preferred embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows a filtration device according to one embodiment of the present invention. Here, the water to be analyzed is assumed to be ultrapure water used in the manufacturing process of products such as semiconductor devices and that comes into contact with the products. However, the water to be analyzed to which the filtration device or water quality control method of the present invention is applicable is not limited to this. Examples of water to be analyzed include functional water, pure water (primary system), and chemical solutions such as IPA (isopropyl alcohol).

[0017] A circulation pipe 11 branches off from an ultrapure water supply pipe 10 for supplying ultrapure water to a use point, and an on-off valve 12 is provided in the circulation pipe 11. The circulation pipe 11 downstream of the on-off valve 12 may be composed of a PFA tube 13 for reducing pressure. A flow rate adjustment valve 23 is provided in a bypass line branching from the circulation pipe 11 to adjust the flow rate of wastewater flowing into the bypass line. A flow meter 24 is provided in the bypass line. An ultrasonic flow rate indicator 25 is also provided downstream of the branch point of the circulation pipe 11 with the bypass line. A filtration device 20 is detachably attached to the tip of the circulation pipe 11 via a piping connector 21. To prevent contamination of the ultrapure water in the ultrapure water supply pipe 10 when the filtration device 20 is attached or detached, it is preferable that the filtration device 20 be attached to a pipe branching off from the ultrapure water supply pipe 10 (such as the circulation pipe 11). The filtration device 20 is, for example, a centrifugal filtration device.

[0018] A particle capture membrane 22 is attached inside the filtration device 20, and ultrapure water, which is the water to be analyzed, flows from the flow pipe 11 via a piping connector 21. The particle capture membrane 22 captures particles in the ultrapure water that flows into the filtration device 20 from the flow pipe 11. The particle capture membrane 22 is attached so that it can be removed from the filtration device 20. A differential pressure adjustment valve 26 is provided downstream of the filtration device 20. The differential pressure adjustment valve 26 is an on-off valve for adjusting the airflow inside the filtration device 20. Further downstream, an integrating flow meter 27 is provided that measures the integrated flow rate of the water to be analyzed that has flowed through the particle capture membrane 22. The water to be analyzed that is supplied via the piping connector 21 and has flowed through the particle capture membrane 22 inside the filtration device 20 is discharged to the outside as filtered water.

[0019] After the target water is passed through the particle trapping membrane 22 for a predetermined period of time, the target water is subjected to at least one of quantitative and qualitative analysis of the target water particles trapped by the particle trapping membrane 22. The accuracy of quantifying the target water particles depends on the cumulative flow rate through the particle trapping membrane 22. The flow rate through the particle trapping membrane 22 also changes depending on pressure fluctuations in the target water. Therefore, even if the flow rate is adjusted at the start of the water flow and multiplied by the flow time, the result does not necessarily match the actual cumulative flow rate. Therefore, in the filtration device 20 of this embodiment, an integrating flow meter 27 is provided downstream of the filtration device 20 (the particle trapping membrane 22) to determine the actual cumulative flow rate of the target water flowing through the particle trapping membrane 22, thereby enabling accurate cumulative flow values ​​to be obtained. The reason for providing the integrating flow meter 27 downstream of the particle trapping membrane 22 in the flow direction of the target water is to avoid contamination from the integrating flow meter 27. The flow rate to the particle trapping membrane 22 is not adjusted based on the measurement value of the integrating flow meter 27.

[0020] After water to be analyzed has been passed through the filtration device 20 of this embodiment for a predetermined period of time, the water flow is stopped and the microparticle trapping membrane 22 is removed from the filtration device 20. The flow of water through the filtration device 20 can be stopped, for example, by fully opening the flow rate adjustment valve 23 and allowing water to pass only from the PFA tube 13 to the bypass line. As will be described later, the microparticles trapped by the microparticle trapping membrane 22 can be quantified immediately after removal, or after a certain amount of time has passed, or in response to a subsequent request. The microparticle trapping membrane 22 is preferably stored in a sealed state to prevent contamination of the microparticle trapping membrane 22 or leakage of microparticles from the microparticle trapping membrane 22 between removal and quantification.

[0021] Next, a water quality control method using the filtration device 20 shown in FIG. 1 will be described with reference to FIG. 2. Here, we will describe a case where water quality control is performed by quantitatively analyzing particles contained as impurities in ultrapure water flowing through the ultrapure water supply pipe 10 as the water to be analyzed. However, qualitative analysis, or both quantitative and qualitative analysis, may also be performed. First, in step 101, the filtration device 20 is connected to the flow pipe 11 via the pipe connector 21. At this time, the particle capture membrane 22 is not attached to the filtration device 20. After the filtration device 20 is connected to the flow pipe 11, in step 102, the on-off valve 12 is opened, and the entire filtration device 20 is flushed (blow-down). After flushing for a certain period of time, in step 103, the flow of water through the filtration device 20 is stopped. To stop the flow of water through the filtration device 20, for example, the flow control valve 23 may be fully opened, as described above. Next, in step 104, the particle capture membrane 22, which has been cleaned in advance, is attached to the filtration device 20. Then, in step 105, the aperture of the flow rate adjustment valve 23 is adjusted in the closing direction to start passing the water to be analyzed through the filtration device 20 (particle trapping membrane 22). At this time, the aperture of the flow rate adjustment valve 23 is adjusted based on the value displayed by the flow rate indicator 25, thereby adjusting the flow rate of the water to be analyzed flowing through the filtration device 20 (particle trapping membrane 22). Then, after the water to be analyzed has been passed through the particle trapping membrane 22 for a predetermined period of time, in step 106, the passing of water through the filtration device 20 is stopped. The specific method for stopping the passing of water through the filtration device 20 is as described above. Thereafter, in step 107, the particle trapping membrane 22 is recovered from the filtration device 20. The particle trapping membrane 22 that has captured particles by passing the water to be analyzed through it is also called a particle trapping membrane sample. 2 is a flowchart focusing on a specific filtration device 20. When the microparticle trapping membrane 22 is recovered in step 107, a replacement microparticle trapping membrane 22 is attached to the filtration device 20 at that point, and water flow through the filtration device 20 with the replacement microparticle trapping membrane 22 attached is resumed, thereby enabling water quality management over a continuous period of time. Note that the on-off valve 12 is normally left open. Flushing is performed even when the microparticle trapping membrane 22 is not attached to the filtration device 20.Furthermore, the on-off valve 12 is closed when changing the sampling point, such as when removing the PFA tube 13 from the circulation pipe 11. It is also possible to install a member to prevent cleaning water from accumulating in the filtration device 20 when cleaning the portion of the circulation pipe 11 downstream of the branch point of the bypass line.

[0022] After the particle trapping membrane 22 is collected, in step 108, the value of the integrated flow measured by the integrating flow meter 27 is recorded. In addition, in step 109, the period during which water was passed through the filtration device 20 (e.g., from what date to what date) is recorded. The value of the integrated flow and the period may be recorded, for example, by writing or recording the water passing period on a physical tag (e.g., a handwritten label, a printed label, or an IC (integrated circuit) chip) and attaching it to the particle trapping membrane 22. Alternatively, if the particle trapping membrane 22 has a serial number or the like, the serial number, the integrated flow rate, and the water passing period may be associated and managed in a database. Note that if the integrated flow rate is measured manually without using the integrating flow meter 27, the order of the processing in step 107 and the processing in step 108 is reversed. Thereafter, in step 110, it is determined whether or not quantification of the particles is necessary at this time. If routine analysis work is being performed, quantification is deemed necessary, and the process proceeds to step 111. If quantification is not necessary at this time but may be performed at a later date for defect analysis, the microparticle trapping membrane 22 is stored in step 112, and the process returns to step 110. Although the case where the microparticle trapping membrane 22 is stored in step 112 has been described, the filtration device 20 may also be stored. In this case, the filtration device 20 is managed by attaching a physical tag as described above to it.

[0023] The number of trapped particles is determined in step 111, and the series of processes for one particular particle trapping membrane 22 is completed.

[0024] The quantification of the trapped particles in step 111 may be performed by quantitative analysis or qualitative analysis using a generally known method. For example, a scanning electron microscope (SEM) may be used to observe and count the trapped particles, the number of particles trapped by the entire trapping membrane may be calculated from the counted value, and the particle concentration in the sample water to be measured may be calculated from the integrating flow meter (volume) of water passing through the trapping membrane. Alternatively, the composition of a predetermined number of particles contained within the observed range may be determined, or the particle sizes and particle size distribution of the particles may be determined.

[0025] When a defect occurs in a product manufactured using ultrapure water, which is the target water for analysis, the defect may be suspected to be due to the quality of the ultrapure water. For example, in semiconductor device manufacturing, if a wafer is cleaned using ultrapure water in a semiconductor cleaning process, and then inspected after several other processes, a defect is detected, and particulates contained in the ultrapure water used during wafer cleaning may be suspected as the cause of the defect. In other words, when a problem occurs with a product, it is determined that quantitative analysis of a particulate trapping film sample for a water flow period corresponding to the time when the product was used with water is necessary, and quantitative analysis is performed. When such an event suspected to be caused by ultrapure water occurs, it is determined in step 110 that quantification is necessary for the particulate trapping film 22 stored in step 112, whose water flow period corresponds to at least the period corresponding to the event, and the trapped particles are quantified for the particulate trapping film sample of that particulate trapping film 22 in step 111. As a result, it is possible to determine whether the defect or other event was caused by particulates in the ultrapure water during the relevant period. Furthermore, the location of the cause of an event such as a defect occurring in a product can be identified from the capture membrane information (described later) of the quantified particle capture membrane sample. For example, as shown in FIG. 3 (details of which will be described later), if filtration devices 20 are installed at the outlet of the ultrafiltration device 38 of the ultrapure water production system 30, at the connection point between the ultrapure water production system 30 and the supply pipe 47, at the main pipes 51 and 52 of the production building 50, or at the branch pipe 56 connecting the main pipes 51 and 52 to an ultrapure water-using device 55, it is possible to identify, from the quantification results and the capture membrane information, which device or component is responsible for an event such as a defect occurring in a product. Furthermore, if multiple filtration devices 20 are installed at predetermined intervals on a long pipe such as the supply pipe 46 or the supply pipe 47 in FIG. 3, it is also possible to identify which location in the supply pipe 46 or the supply pipe 47 is responsible for an event such as a defect occurring in a product. The filtration device 20 whose water flow period is the period corresponding to the event refers to the filtration device 20 whose water flow period includes the period in which it was in contact with the water to be analyzed at some point in the past during the manufacturing process of the product in which the event occurred. The water flow period here is information indicating the period from which the date and time when water was flowing can be identified (the same applies to the following explanation).For example, the water flow period is information that includes at least one of the date and time when water flow through the filtration device 20 (particle trapping membrane 22) started and the date and time when water flow ended.

[0026] In this embodiment, because the water flow period is recorded for each microparticle trapping membrane 22, even if a defect is discovered after the fact, it is possible to easily find and analyze the microparticle trapping membrane 22 with the water flow period corresponding to the defect from among the stored microparticle trapping membranes 22. To perform a more precise defect analysis, it is preferable to not only quantify the microparticle trapping membranes 22 with the water flow period corresponding to the period in which the defect occurred, but also quantify the microparticle trapping membranes 22 with the water flow periods corresponding to the periods before and after the period in which the defect occurred.

[0027] According to this embodiment, the microparticles in the ultrapure water can be managed as continuous quantitative values ​​for each specified period, and when a decrease in the yield of a manufactured product occurs, by comparing the manufacturing process history of the product with the period of time that water was passed through the microparticle capture membrane and the quantitative results of the microparticles, it becomes possible to quickly determine whether the decrease in yield was caused by the ultrapure water.

[0028] Next, an example of applying the above-mentioned water quality control method to a semiconductor device manufacturing factory will be described. Figure 3 is a flow chart showing the production and consumption of ultrapure water in a semiconductor device manufacturing factory, and shows an example of the locations where filtration equipment 20 is connected in the semiconductor device manufacturing factory.

[0029] The illustrated semiconductor device manufacturing plant comprises a separate subsystem: an ultrapure water production system (secondary pure water production system) 30, which receives primary pure water and produces ultrapure water, and a manufacturing building 50, where the ultrapure water is actually used. The ultrapure water production system 30 includes a tank 31 for receiving and temporarily storing the primary pure water, a pump (P) 32 attached to the outlet of the tank 31, a heat exchanger (HE) 33 attached to the outlet of the pump 32, an ultraviolet oxidation system (UV) 34, a membrane degassing system (DG) 35, a non-regenerative ion exchanger (CP) 37, and an ultrafiltration system (UF) 38, which perform the processes for producing ultrapure water. The ultraviolet oxidation system 34, membrane degassing system 35, non-regenerative ion exchanger 37, and ultrafiltration system 38 are connected in series to the outlet of the heat exchanger 33, in that order. A vacuum pump (VP) 36 is connected to the membrane degassing system 35. The outlet water from the ultrafiltration device 38 is ultrapure water, a portion of which is supplied to the manufacturing building 50 via supply pipes 46 and 47, and the remaining ultrapure water not supplied to the manufacturing building 50 is returned to the tank 31 via the circulation pipe 39. A valve 40 is provided in the circulation pipe 39, for example, to maintain a constant water pressure in the path through which the ultrapure water circulates. Nitrogen (N2) gas is supplied to the tank 31 to purge the oxygen and minimize the amount of dissolved oxygen in the ultrapure water. Nitrogen gas is also supplied to the membrane degassing device 35 to perform a nitrogen sweep in addition to removing oxygen. The configuration and arrangement of the ultrapure water production system 30 are not limited to those shown in the figure.

[0030] Of the supply pipes 46, 47 to the manufacturing building 50, an ion adsorbent 41 for capturing trace amounts of ionic impurities in the ultrapure water and a particle removal filter (not shown) for capturing particle are provided on the supply pipe 46 on the ultrapure water production apparatus 30 side. The particle removal filter is provided downstream of the ion adsorbent 41 on the supply pipes 46, 47. The ion adsorbent 41 does not necessarily have to be provided.

[0031] In the manufacturing building 50, main pipes 51 and 52 are provided, which are connected to the supply pipes 46 and 47, respectively, and a plurality of ultrapure water-using apparatuses 55 are connected to the main pipes 51 and 52 via branch pipes 56. The ultrapure water-using apparatuses 55 are, for example, cleaning apparatuses, etching apparatuses, exposure apparatuses, etc. At the inlet sides of the main pipes 51 and 52, an ion adsorbent 53 that captures trace amounts of ionic impurities contained in the ultrapure water supplied from the supply pipes 46 and 47, respectively, and a particle removal filter (not shown) that captures particle matter are provided. The particle removal filter is provided downstream of the ion adsorbent 53 on the supply pipes 46 and 47. The ion adsorbent 53 is not necessarily provided.

[0032] An example of a location where the filtration device 20 shown in FIG. 1 can be installed is indicated by the symbol M in FIG. 3. In the ultrapure water production system 30, the filtration device 20 may be installed at the outlet of the ultrafiltration device 38 or at the connection point with the supply pipe 47. In the manufacturing building 50, the filtration device 20 may be installed on each main pipe 51, 52, or on the branch pipe 56 connected to each ultrapure water-using device 55. The installation locations and number of filtration devices 20 are not limited to those shown in the figure, and the filtration device 20 can be installed at any location. Each filtration device 20 is connected to a pipe through which ultrapure water flows via an on-off valve 12, as shown in FIG. 1. The on-off valve 12 is normally open and is closed when the sampling point is changed. If a recovered water system is installed in the semiconductor device factory, the discharged water from the filtration device 20 is preferably returned to the recovered water system.

[0033] The following describes an example of how to use the above-described filtering device. (First system example)

[0034] Fig. 4 is a diagram showing a first example of an information processing system using the filtration device 20 shown in Fig. 1. Here, a case where quantitative analysis of particulates is performed using a quantitative device as the analysis device will be described, but qualitative analysis may also be performed using a qualitative device, or quantitative analysis and qualitative analysis may also be performed using a quantitative device and a qualitative device.

[0035] The information processing system shown in FIG. 4 includes a filtration device 100, a quantification device (analysis device) 200, and an information processing device 300. The filtration device 100 corresponds to the filtration device 20 shown in FIG. 1. Furthermore, a notification unit 110 is connected to the filtration device 100. The notification unit 110 issues a predetermined notification, such as a notification indicating that a predetermined period of time has elapsed since the particle trapping membrane (particle trapping membrane 22 shown in FIG. 1; the same applies hereinafter) was attached to the filtration device 100. Alternatively, the notification unit 110 issues a predetermined notification, such as a notification indicating that a cumulative value measured by an integrating flow meter (integrating flow meter 27 shown in FIG. 1; the same applies hereinafter) provided downstream of the filtration device 100 after the particle trapping membrane was attached to the filtration device 100 reaches a predetermined value. Note that the filtration device 100 also includes the integrating flow meter 27 shown in FIG. 1. At this time, the notification unit 110 issues a notification urging the user to remove the particle trapping membrane from the filtration device 100. Furthermore, the notification unit 110 may be provided inside the filtering device 100, or may be displayed on another device such as a terminal device having an information display function.

[0036] The quantitative analysis device 200 performs quantitative analysis on the particle trapping film that has trapped the particles. The specific method of quantitative analysis is as described above. The method of identifying the particle trapping film that is the subject of quantitative analysis will be described later.

[0037] Fig. 5 is a diagram showing an example of the internal configuration of information processing device 300 shown in Fig. 4. As shown in Fig. 5, information processing device 300 shown in Fig. 4 has an input unit 310, a database 320, a search unit 330, and an output unit 350. Note that Fig. 5 shows only the main elements related to this embodiment among the components included in information processing device 300 shown in Fig. 4.

[0038] The input unit 310 inputs input information to the information processing device 300 based on an operation received from outside. Specifically, the input unit 310 receives a predetermined operation from outside and inputs information based on the received operation. For example, information input by the input unit 310 includes information instructing a search for a microparticle trapping film sample when a wafer defect is detected in a semiconductor device manufacturing process and it is determined that a quantitative analysis of a microparticle trapping film sample for a water flow period corresponding to the time when wafer cleaning water was used is necessary. Examples of the input unit 310 include a keyboard, a mouse, a touch panel, and the like. The input unit 310 may also display a GUI (Graphical User Interface) that prompts the user to input predetermined information, and input information based on an operation performed in accordance with the display. Alternatively, information recorded by the filtration device 100 or information notified by the notification unit 110 may be transmitted to the information processing device 300, and the input unit 310 may receive the transmitted information to input the information.

[0039] The database 320 stores period information (including information such as the date and time when water started and ended flowing through the particle trapping membrane) indicating the period during which the particle trapping membrane was attached to the flow pipe (the period during which water was passed through the particle trapping membrane to capture the particles) in association with the trapping membrane identification information unique to the particle trapping membrane. The database 320 also stores the installation information of the filtration device 100 to which the particle trapping membrane is attached (or was attached) in association with the trapping membrane information. The method of registering information in the database 320 is not particularly limited. For example, when registering period information, information including the date and time when the on-off valve 12 is opened and closed may be transmitted to the database 320 and stored (registered) as period information. When registering period information, information including the date and time when the target water starts and stops flowing through the integrating flow meter 27 may be transmitted to the database 320 and stored (registered) as period information. Furthermore, when registering capture membrane identification information, an identification tab such as a barcode or two-dimensional code may be attached to the microparticle capture membrane 22, and the attached identification tab may be read by a code reader (reading device), and the read information may be sent to the database 320 and stored (registered) as capture membrane information.

[0040] FIG. 6 is a diagram showing an example of the correspondence between installation information and trapping membrane information stored in the database 320 shown in FIG. 5. As shown in FIG. 6, the database 320 shown in FIG. 5 stores "customer number," "system number," and "equipment number" that can identify the installation location of the filtration device 100 equipped with the microparticle trapping membrane, in association with "trapping membrane information." The "customer number," "system number," and "equipment number" are collectively referred to as installation information. The "customer number" is customer identification information uniquely assigned to the customer in which the filtration device 100 equipped with the microparticle trapping membrane is installed. The "system number" is system identification information uniquely assigned to the system constructed in the customer's facility. The "equipment number" indicates which device in the system the filtration device 100 is installed in and is device identification information uniquely assigned to the installed device. In this way, the installation location of the filtration device 100 equipped with the microparticle trapping membrane can be identified by using the "customer number," "system number," and "equipment number." Details of the "trapping membrane information" will be described later.

[0041] For example, as shown in FIG. 6, customer No. "A001," system No. "1," equipment No. "1," and trapping membrane information "A001-1-1" are stored in association with each other. This indicates that a device with equipment identification information "1" installed in a system with system identification information "1" constructed in the facility of a customer with customer identification information "A001" is (was) equipped with a particle trapping membrane indicated by trapping membrane information "A001-1-1." Furthermore, customer No. "A001," system No. "1," equipment No. "2," and trapping membrane information "A001-1-2" are stored in association with each other. This indicates that a device with equipment identification information "2" installed in a system with system identification information "1" constructed in the facility of a customer with customer identification information "A001" is (was) equipped with a particle trapping membrane indicated by trapping membrane information "A001-1-2." Furthermore, customer No. "A001," system No. "2," equipment No. "1," and trapping membrane information "A001-2-1" are stored in association with each other. This indicates that a device with equipment identification information "1" installed in a system with system identification information "2" constructed in the facility of a customer with customer identification information "A001" is (was) equipped with a particle trapping membrane indicated by trapping membrane information "A001-2-1." Furthermore, customer No. "A001," system No. "2," equipment No. "2," and trapping membrane information "A001-2-2" are stored in association with each other. This indicates that a device with equipment identification information "2" installed in a system with system identification information "2" constructed in the facility of a customer with customer identification information "A001" is (was) equipped with a particle trapping membrane indicated by trapping membrane information "A001-2-2."

[0042] FIG. 7 is a diagram showing an example of the correspondence between period information and trapping film identification information stored in the database 320 shown in FIG. 5. This correspondence is the trapping film information described above. The trapping film information shown in FIG. 7 is one of the trapping film information shown in FIG. 6 (trapping film information "A001-1-1"), and if nine pieces of trapping film information are stored in the database 320 as shown in FIG. 6, nine pieces of trapping film information with the correspondence shown in FIG. 7 are stored in the database 320. Therefore, for example, the trapping film information shown in FIG. 7 corresponds to one piece of trapping film information "A001-1-1" shown in FIG. 6.

[0043] 5, the database 320 stores, as shown in Fig. 7, a "period" that is period information indicating the period during which the microparticle trapping membrane was attached to the filtration device 100, a "flow rate [L]" that is the accumulated amount of water flowing during that period, and a "trapping membrane No." that is trapping membrane identification information uniquely assigned to that microparticle trapping membrane, all of which are associated with each other and stored as a single piece of trapping membrane information. The flow rate is the accumulated value measured by an integrating flow meter during that period.

[0044] For example, as shown in FIG. 7, the period "2019 / 5 / 1 to 2019 / 5 / 5," the flow rate "1000 [L]," and the trapping membrane number "A00010001" are stored in association with each other. This indicates that a microparticle trapping membrane with the trapping membrane identification information "A00010001" was attached to the filtration device 100 for five days, from May 1, 2019 to May 5, 2019, and that the amount of water to be analyzed that flowed through this microparticle trapping membrane during that period was 1000 [L]. Furthermore, the period "2019 / 5 / 6 to 2019 / 5 / 10," the flow rate "980 [L]," and the trapping membrane number "A00020001" are stored in association with each other. This indicates that a particle trapping membrane with trapping membrane identification information "A00020001" was attached to the filtration device 100 for five days, from May 6, 2019, to May 10, 2019, and that the amount of water to be analyzed that flowed through this particle trapping membrane during that period was 980 [L]. The period "2019 / 5 / 11 to 2019 / 5 / 15," the flow rate "1000 [L]," and the trapping membrane number "A00030001" are stored in association with each other. This indicates that a particle trapping membrane with trapping membrane identification information "A00030001" was attached to the filtration device 100 for five days, from May 11, 2019, to May 15, 2019, and that the amount of water to be analyzed that flowed through this particle trapping membrane during that period was 1000 [L]. Additionally, the period "2019 / 5 / 16 to 2019 / 5 / 20," the flow rate "990 [L]," and the trapping membrane number "A00040001" are stored in association with each other. This indicates that the particle trapping membrane with the trapping membrane identification information "A00040001" was attached to the filtration device 100 for five days, from May 16, 2019 to May 20, 2019, and that the amount of water to be analyzed that flowed through this particle trapping membrane during that period was 990 [L]. This association is registered and stored after each particle trapping membrane is removed from the filtration device 100. This registration method may involve transmitting this information from the filtration device 100 to the information processing device 300 and registering it, or it may involve registering it via another medium.5, the period information "period" indicates only information indicating the date, but it also includes information indicating the date and time including the time (hours). In other words, the period information includes information indicating the date and time when the particulate capture membrane was attached to the filtration device 100 and information indicating the date and time when the particulate capture membrane was removed from the filtration device 100.

[0045] The search unit 330 searches the database 320 for capture membrane identifying information based on the date and time information (information about when the product used water when the problem occurred) included in the input information input by the input unit 310. Specifically, the search unit 330 searches the database 320 for a period that includes the date and time indicated by the date and time information included in the input information input by the input unit 310, and then searches the database 320 for capture membrane identifying information associated with the searched period. In this case, the search unit 330 searches the database 320 for capture membrane information based on the installation information of the filtration device included in the input information input by the input unit 310, and then searches the database 320 for capture membrane identifying information based on the searched capture membrane information and the date and time information. For example, if the installation information included in the input information has a customer number of "A001," a system number of "1," an equipment number of "1," and date and time information of "May 3, 2019," the search unit 330 searches the database 320 for capture membrane information for which the customer number is "A001," the system number is "1," and the equipment number is "1," and from the association of the searched capture membrane information "A001-1-1," it searches for the capture membrane number "A00010001" associated with the period "2019 / 5 / 1~2019 / 5 / 5," which is the period including the date and time information "May 3, 2019."

[0046] The system configuration of a customer's facility may be registered in database 320 in advance, and search unit 330 may perform a search based on the system configuration. For example, if a device with customer number "A001," system number "1," and device number "1" and a device with customer number "A001," system number "1," and device number "2" are considered to potentially affect each other based on their system configurations, even if the installation information included in the input information has customer number "A001," system number "1," and device number "1," search unit 330 may also search for capture membrane information for the device with customer number "A001," system number "1," and device number "2." Here, to determine whether or not there is an effect on each other, a determination model may be generated using machine learning based on the system configuration and past determination results, and the determination may be made using the determination model. For example, if an apparatus with customer number "A001", system number "1", and equipment number "1" and an apparatus with customer number "A001", system number "1", and equipment number "2" are installed in series, or if past analysis results show a correlation between the results of the two, it may be determined whether they affect each other. In this way, by analyzing the apparatuses that affect each other, if the cause of a product defect is a contaminant contained in ultrapure water, it is possible to determine which of the multiple apparatuses installed in the system is generating the contaminant, that is, to identify the apparatus that is generating the contaminant.

[0047] The output unit 350 outputs the trapping film identifying information retrieved by the retrieval unit 330. The output method of the trapping film identifying information performed by the output unit 350 may be, for example, transmission to another device, screen display, audio output, or printing.

[0048] The following describes an information processing method in the information processing system shown in Fig. 4. Fig. 8 is a flowchart for explaining an example of processing in the filtering device 100 in the information processing method in the information processing system shown in Fig. 4.

[0049] First, the microparticle trapping membrane is attached to the filtration device 100 (step S11). Then, water starts to flow through the flow pipe 11 (step S12). At this time, after the microparticle trapping membrane is attached to the filtration device 100, the opening of the flow rate adjusting valve 23 shown in FIG. 1 is adjusted from the fully open state to the closing direction, and water starts to flow through the microparticle trapping membrane.

[0050] Thereafter, it is determined whether it is time to stop the water flow (step S13). Here, it is determined that it is time to stop the water flow when a predetermined period of time has elapsed since the start of the water flow or when the integrated value of the water flow rate reaches a predetermined value. The elapse of the predetermined period of time may be determined using a timer. The integrated value of the water flow rate may also be measured using an integrated flow meter. When these timings are reached, the notification unit 110 may notify the system administrator, operator, or maintainer (hereinafter referred to as the administrator, etc.) that the timing has been detected by displaying a message or the like. Thereafter, the water flow through the particle trapping membrane is stopped (step S14). At this time, the flow rate adjustment valve 23 shown in FIG. 1 is fully opened. Also, the person who received the notification adjusts the opening rate of the flow rate adjustment valve 23. Then, the particle trapping membrane is removed from the filtration device 100 (step S15). At this time, a new particle trapping membrane is attached to the filtration device 100. The timer and integrating flow meter are reset each time a microparticle trapping membrane is attached to the filtration device 100 (each time the microparticle trapping membrane is replaced). The time from when water flow to the filtration device 100 is stopped to replace the microparticle trapping membrane until when water flow starts again is set as short as possible to ensure continuity of the water flow period for the microparticle trapping membrane.

[0051] Information such as the water flow period of the removed particle trapping membrane is stored in the database 320 of the information processing device 300. The stored information is the same as that shown in Fig. 7, and multiple pieces of information are stored for each particle trapping membrane in correspondence with each other. This storage is performed via the input unit 310 of the information processing device 300. The removed particle trapping membrane is assigned trapping membrane identification information and stored in a specified storage location.

[0052] Thereafter, when quantitative analysis becomes necessary, a search request is sent to the information processing device 300. Here, when a defect occurs in a product manufactured using the ultrapure water to be analyzed, and it is necessary to confirm whether the cause of the defect lies in the quality of the ultrapure water, quantitative analysis must be performed. To do this, it is necessary to search for and extract the target particle trapping membrane sample (i.e., the particle trapping membrane sample that was passed through water during the water passing period corresponding to the time when the product used water when the problem occurred in the product).

[0053] FIG. 9 is a flowchart illustrating an example of search processing in the information processing device 300, part of the information processing method in the information processing system shown in FIG.

[0054] The input unit 310 determines whether a request for a search for a particle trapping film has been received (step S21). This request may be based on a predetermined operation performed by a system administrator or the like on the input unit 310 to request a search for a particle trapping film, and the operation is received by the input unit 310. This predetermined operation includes installation information and date and time information of the target device (the device in which the defect occurred). The input unit 310 outputs the installation information and date and time information from the input information to the search unit 330. The search unit 330 searches the database 320 for trapping film identification information based on the installation information and date and time information output from the input unit 310 (step S22). Specifically, for example, the search unit 330 searches the database 320 for trapping film information based on the installation information output from the input unit 310, and searches the database 320 for trapping film identification information associated with the period that includes the date and time information output from the input unit 310 from the retrieved trapping film information. Then, the output unit 350 outputs the trapping membrane identifying information retrieved by the retrieval unit 330 (step S23).

[0055] The administrator or other person then retrieves the microparticle capture membrane with the capture membrane identification information output from output unit 350 from the storage location and performs quantification using quantification device 200. The results of the quantitative analysis and the integrated value measured by the integrating flow meter are then used to calculate the microparticle concentration in the water being analyzed. The administrator or other person provides the quantification results and the microparticle concentration in the water being analyzed to the desired recipient.

[0056] In this way, in a water quality management system, a filtration device equipped with a microparticle trapping membrane is removed at a predetermined time, the microparticle trapping membranes of the removed filtration device are stored, and from the stored microparticle trapping membranes, the microparticle trapping membranes of the filtration device that was installed at a specified installation location and during a specified period are searched for, and quantitative analysis of the searched microparticle trapping membranes is performed and the results are provided. As a result, the treatment status of the water to be analyzed at a specified location and date and time can be recognized. (Second system example)

[0057] Fig. 10 is a diagram showing a second example of an information processing system using the filtration device 20 shown in Fig. 1. Here, a case where quantitative analysis of particulates is performed using a quantitative device as the analysis device will be described, but qualitative analysis may also be performed using a qualitative device, or quantitative analysis and qualitative analysis may also be performed using a quantitative device and a qualitative device.

[0058] The information processing system shown in FIG. 10 includes a filtration device 101, a quantification device (analysis device) 201, and an information processing device 301. The filtration device 101 corresponds to the filtration device 20 shown in FIG. 1. The filtration device 101 transmits information on the date and time when the particle trapping membrane was attached to the flow pipe, information on the date and time when it was removed from the flow pipe, and identification information of the particle trapping membrane to the information processing device 301. A notification unit 110 is also connected to the filtration device 101. The notification unit 110 issues a predetermined notification, such as a notification indicating that a predetermined period of time has elapsed since the particle trapping membrane included in the filtration device 101 was attached to the flow pipe. Alternatively, the notification unit 110 issues a predetermined notification, such as a notification indicating that a cumulative value measured by an integrating flow meter included in the filtration device 101 after the particle trapping membrane included in the filtration device 101 was attached to the flow pipe has reached a predetermined value. At this time, the notification unit 110 issues a notification urging the user to remove the particle trapping membrane from the flow pipe. Furthermore, the notification unit 110 may be provided inside the filtering device 101, or may be provided to display information on another device such as a terminal device that has an information display function.

[0059] The quantitative analysis device 201 performs quantitative analysis of the particles captured by the particle capture film. The specific method of quantitative analysis is as described above. A method for identifying the particle capture film to be subjected to quantitative analysis will be described later. The quantitative analysis device 201 provides the results of the quantitative analysis to the information processing device 301. This method of providing information may involve transmitting information indicating the analysis results from the quantitative analysis device 201 to the information processing device 301, or may involve providing the information via another medium.

[0060] Fig. 11 is a diagram showing an example of the internal configuration of the information processing device 301 shown in Fig. 10. As shown in Fig. 11, the information processing device 301 shown in Fig. 10 has an input unit 311, a database 321, a search unit 331, an extraction unit 341, and an output unit 351. Note that Fig. 11 shows only the main elements related to this embodiment among the components included in the information processing device 301 shown in Fig. 10.

[0061] The input unit 311 inputs input information to the information processing device 301 based on an operation received from outside. Specifically, the input unit 311 receives a predetermined operation from outside and inputs information based on the received operation. For example, information input by the input unit 311 includes information instructing a search for a microparticle trapping film sample when a wafer defect is detected in a semiconductor device manufacturing process and it is determined that a quantitative analysis of a microparticle trapping film sample for a water flow period corresponding to the time when wafer cleaning water was used is necessary. Examples of the input unit 311 include a keyboard, a mouse, a touch panel, and the like. The input unit 311 may also display a GUI that prompts the user to input predetermined information, and input information based on an operation performed in accordance with the display. Alternatively, information recorded by the filtration device 101 and information notified by the notification unit 110 may be transmitted to the information processing device 301, and the input unit 311 may input the information by receiving the transmitted information.

[0062] The database 321 stores, as trapping membrane information, period information indicating the water flow period (including the date and time when water flow through the microparticle trapping membrane started and ended) in association with trapping membrane identification information uniquely assigned to the microparticle trapping membrane. The database 321 also stores, associating with each other, installation information for the filtration device 101 to which the microparticle trapping membrane is attached (or was attached), and trapping membrane information. The storage manner of this information is the same as that shown in FIGS. 6 and 7. The database 321 may also store analysis results transmitted from the quantification device 201, for example, when a quantitative analysis is performed after determining that quantitative analysis of a microparticle trapping membrane sample during a water flow period corresponding to the time when the product used water when a problem occurred. The analysis results transmitted from the quantification device 201 are stored in the database 321 via the input unit 311.

[0063] The search unit 331 searches the database 321 for capture membrane identifying information based on the date and time information included in the input information input by the input unit 311. Specifically, the search unit 331 searches the database 321 for a period that includes the date and time indicated by the date and time information included in the input information input by the input unit 311, and then searches the database 321 for capture membrane identifying information associated with the searched period. In this case, the search unit 331 searches the database 321 for capture membrane information based on the installation information of the filtration device included in the input information input by the input unit 311, and then searches the database 321 for capture membrane identifying information based on the searched capture membrane information and the date and time information. For example, if the installation information included in the input information has a customer number of "A001," a system number of "1," an equipment number of "1," and date and time information of "May 3, 2019," the search unit 331 searches the database 321 for capture membrane information for which the customer number is "A001," the system number is "1," and the equipment number is "1," and from the association of the searched capture membrane information "A001-1-1," it searches for the capture membrane number "A00010001" associated with the period "2019 / 5 / 1~2019 / 5 / 5," which is the period including the date and time information "May 3, 2019."

[0064] The system configuration of a customer's facility may be registered in database 321 in advance, and search unit 331 may perform a search based on the system configuration. For example, if a device with customer No. "A001," system No. "1," and device No. "1" and a device with customer No. "A001," system No. "1," and device No. "2" are considered to potentially affect each other based on their system configurations, even if the installation information included in the input information has customer No. "A001," system No. "1," and device No. "1," the search unit 331 may also search for capture membrane information for the device with customer No. "A001," system No. "1," and device No. "2." Here, to determine whether or not there is an effect on each other, a determination model may be generated using machine learning based on the system configuration and past determination results, and the determination may be made using the determination model. For example, if an apparatus with customer number "A001", system number "1", and equipment number "1" and an apparatus with customer number "A001", system number "1", and equipment number "2" are installed in series, or if past analysis results show a correlation between the results of the two, it may be determined whether they affect each other. In this way, by analyzing the apparatuses that affect each other, if the cause of a product defect is a contaminant contained in ultrapure water, it is possible to determine which of the multiple apparatuses installed in the system is generating the contaminant, that is, to identify the apparatus that is generating the contaminant.

[0065] The extraction unit 341 extracts provided information, which is information corresponding to the input information, from the results of quantitative analysis provided (transmitted) from the quantification device 201 for the microparticle capture membrane to which the capture membrane identification information searched by the search unit 331 has been assigned. Here, the input information may include, for example, specific analysis content. In this case, the extraction unit 341 extracts results corresponding to the analysis content included in the input information from the results of quantitative analysis performed by the quantification device 201. If the quantitative analysis provided (transmitted) from the quantification device 201 is stored in the database 321, the extraction unit 341 extracts provided information, which is information corresponding to the input information, from the results of quantitative analysis stored in the database 321.

[0066] The output unit 351 outputs the trapping film identification information searched by the search unit 331. The output unit 351 outputs, as provided information, the results of the quantitative analysis performed by the quantification device 201 on the microparticle trapping film to which the trapping film identification information searched by the search unit 331 has been assigned. Furthermore, when the extraction unit 341 extracts provided information corresponding to the input information from the results of the quantitative analysis performed by the quantification device 201, the output unit 351 outputs the provided information extracted by the extraction unit 341. The provided information output by the output unit 351 may be, for example, transmitted to another device, displayed on a screen, output as audio, printed, or turned on or flashing a predetermined lamp.

[0067] FIG. 12 is a sequence diagram illustrating an example of an information processing method in the information processing system shown in FIG.

[0068] First, the microparticle trapping membrane is attached to the filtration device 101, and water flow through the filtration device 101 begins (step S1). At this time, after the microparticle trapping membrane is attached to the filtration device 101, the opening of the flow rate adjustment valve 23 shown in FIG. 1 is adjusted from a fully open state toward a closed state, and water flow through the microparticle trapping membrane begins. Thereafter, when a predetermined period of time has passed, or when the integrated value measured by the integrating flow meter 27 shown in FIG. 1 reaches a predetermined value, water flow through the filtration device 101 is terminated. This termination of water flow through the filtration device 101 is not directly triggered by the detection of the passage of the predetermined period of time or the detection of the integrated value reaching a predetermined value, but rather by the detection of such detection starting a notification process, and the person receiving the notification adjusts the opening of the flow rate adjustment valve 23, thereby terminating water flow through the filtration device 101. At this time, the opening of the flow rate adjustment valve 23 shown in FIG. 1 is set to a fully open state. Here, the filtration device 101 may have a timer that measures the time since water began to flow through the particle trapping membrane, and when a preset time has elapsed, the notification unit 110 may notify the user of this and terminate the flow of water through the filtration device 101. Alternatively, when the integrated value measured by the integrating flow meter reaches a preset value, the notification unit 110 may notify the user of this and terminate the flow of water through the filtration device 101. The notification from the notification unit 110 may be sent to a system administrator or the like, who may then fully open the flow control valve 23 to terminate the flow of water. The notification from the notification unit 110 may also be sent to the flow control valve 23, which may then automatically fully open the flow of water. Then, the particle trapping membrane is removed from the filtration device 101 (step S2). At this time, a new particle trapping membrane is attached to the filtration device 101. The timer and the integrating flow meter are reset each time a particle trapping membrane is attached to the filtration device 101 (each time the particle trapping membrane is replaced).

[0069] Thereafter, information about the removed particle trapping membrane is provided to the information processing device 301 (step S3). The provided information includes information about the period of time the particle trapping membrane has been removed, the integrated value measured by the integrating flow meter, the trapping membrane identification information of the particle trapping membrane, and installation information of the filtration device 101 on which the particle trapping membrane was attached. This information may be provided by the filtration device 101 transmitting the information to the information processing device 301, or by providing the information via other media. The information about the particle trapping membrane may be provided to the information processing device 301 after step S1. In this case, the provided information is information indicating the date and time when the particle trapping membrane was attached to the filtration device 101 and water flow through the filtration device 101 began. Then, storage processing is performed in the information processing device 301 (step S4). The removed particle trapping membrane is stored in a predetermined location so that it can be identified using its trapping membrane identification information.

[0070] Next, when the information processing device 301 instructs the quantitation device 201 to perform quantitative analysis (step S5), the quantitation device 201 performs the quantitative analysis (step S6). At this time, the information processing device 301 specifies the trapping membrane identification information to instruct the quantitation device 201 to perform quantitative analysis, and the quantitation device 201 performs quantitative analysis of the microparticles captured by the microparticle trapping membrane to which the instructed trapping membrane identification information has been assigned. This quantitative analysis instruction may be given by the information processing device 301 transmitting information indicating a request for quantitative analysis to the quantitation device 201, or may be provided via other media. When the quantitative analysis is completed, the quantitation device 201 provides the results to the information processing device 301 (step S7). The results of this quantitative analysis may be provided by the quantitation device 201 transmitting information indicating the results of the quantitative analysis to the information processing device 300, or may be provided via other media. Then, the information processing device 301 performs output processing (step S8).

[0071] Fig. 13 is a flowchart illustrating an example of the detailed processing of step S4 described using the sequence diagram shown in Fig. 12. When information is provided from the filtration device 101 in step S3, the database 321 stores the provided information, which is the period information (water flow period), the integrated value, the capture membrane identification information, and the installation information, in association with each other (step S41). This association is stored in the format shown in Figs. 7 and 8.

[0072] The input unit 311 then determines whether a request for quantitative analysis has been made (step S42). At this time, the input unit 311 may determine that a request for quantitative analysis has been made if information corresponding to an operation received from an external device or information transmitted from another externally connected device includes a request for quantitative analysis, installation information, and date and time information. If a request for quantitative analysis has been made, the input unit 311 outputs the installation information and date and time information from the input information to the search unit 331. The search unit 331 searches the database 321 for capture film identifying information based on the installation information and date and time information output from the input unit 311 (step S43). Specifically, for example, the search unit 331 searches the database 321 for capture film information based on the installation information output from the input unit 311, and searches the database 321 for capture film identifying information associated with the period that includes the date and time information output from the input unit 311 from the retrieved capture film information. When the search unit 331 has found the trapping membrane identifying information, it designates the found trapping membrane identifying information and instructs the quantitative analysis device 201 to perform a quantitative analysis (step S44).

[0073] FIG. 14 is a flowchart illustrating an example of detailed processing of step S8 described using the sequence diagram shown in FIG. 12. When the input unit 311 receives the results of the quantitative analysis from the quantitation apparatus 201 (step S71), the extraction unit 341 extracts information to be provided, which is information corresponding to the input information, from the results of the quantitative analysis received by the input unit 311 (step S72). The input information may specify the content of the quantitative analysis (e.g., the type of particle to be analyzed). In this case, the extraction unit 341 extracts the analysis content included in the input information from the results of the quantitative analysis performed by the quantitation apparatus 201. Next, the output unit 351 outputs the information to be provided extracted by the extraction unit 341 (step S73). Note that the quantitation apparatus 201 may calculate the particle concentration in the target water using the results of the quantitative analysis and the integrated value measured by the integrating flow meter, and the input unit 311 may receive the particle concentration in the target water.

[0074] In this way, in a water quality management system, the particulate trapping membranes attached to the filtration device are replaced at predetermined times, the removed particulate trapping membranes are stored, and from among the stored particulate trapping membranes, the particulate trapping membranes that were attached at a specified installation location and during a specified period are searched for, quantitative analysis of the searched particulate trapping membranes is performed, and the results are output. This makes it possible to recognize the treatment status of the water being analyzed at a specified location and date and time.

[0075] Although the above description has been given with each component assigned a respective function (process), this assignment is not limited to the above. Furthermore, the configuration of the components is also not limited to the above-described form, and is merely an example. Furthermore, the present invention can be applied to systems that control and manage the content of fine particles in liquids, in addition to systems that perform water treatment.

[0076] The processes performed by the information processing devices 300 and 301 described above may be performed by logic circuits individually designed for each purpose. Alternatively, a computer program (hereinafter referred to as the program), which describes the process steps, may be recorded on a recording medium readable by the information processing devices 300 and 301, and the program recorded on the recording medium may be read and executed by the information processing devices 300 and 301. Recording media readable by the information processing devices 300 and 301 include removable recording media such as floppy disks, magneto-optical disks, digital versatile discs (DVDs), compact discs (CDs), Blu-ray discs (registered trademark), and universal serial bus (USB) memories, as well as memories such as read-only memories (ROMs), random access memories (RAMs), and hard disc drives (HDDs) built into the information processing devices 300 and 301. The programs recorded on the recording media are read by a CPU (CPU) provided in the information processing devices 300 and 301, and the same processes as those described above are performed under the control of the CPU. Here, the CPU operates as a computer that executes a program read from a recording medium on which the program is recorded. [Explanation of symbols]

[0077] 10 Ultrapure water supply piping 11 Flow pipe 12 On-off valve 13 PFA tube 20,100,101 Filtration equipment 21 Pipe Connector 22 Particulate capture membrane 23 Flow control valve 24 Flow meter 25 Flow rate indicator 26 Differential pressure adjustment valve 27 Integral flow meter 110 Notification Department 200,201 Quantitative equipment (analytical equipment) 300, 301 Information processing equipment 310,311 Input section 320,321 databases 330,331 Search Department 341 Extraction part 350,351 Output section

Claims

1. A water quality control method for performing at least one of quantitative analysis and qualitative analysis of particles contained in ultrapure water, a step of attaching a particle capture membrane for capturing the particles to a filtration device connected to a flow pipe through which the ultrapure water flows; a step of passing the ultrapure water from the flow pipe through the particle capture membrane attached to the filtration device for a predetermined period of time to capture particles contained in the ultrapure water and obtain a particle capture membrane sample; a step of performing at least one of quantitative analysis and qualitative analysis of the microparticle capture membrane sample during the target water flow period at an arbitrary timing; and After the predetermined period has elapsed, the microparticle trapping membrane sample is removed from the filtration device, the removed microparticle trapping membrane sample is sealed, and the microparticle trapping membrane sample is kept sealed until the microparticle trapping membrane sample is analyzed; After the predetermined period has elapsed, a flow rate control valve provided in a bypass line branching off from the circulation pipe for draining the ultrapure water is fully opened, thereby allowing the ultrapure water to flow only through the bypass line.

2. The water quality control method according to claim 1, wherein the microparticle capture membrane sample is collected, a new microparticle capture membrane is attached to the filtration device, and ultrapure water is repeatedly passed through the filtration device, thereby obtaining the microparticle capture membrane sample continuously over a plurality of periods.

3. 3. The water quality control method according to claim 2, wherein the period of time that water has been passed through each of the plurality of microparticle trapping membrane samples is recorded.

4. 4. The water quality control method according to claim 3, wherein when analysis becomes necessary after the ultrapure water has been used in the manufacturing process of a product, at least one of quantitative analysis and qualitative analysis is performed on the microparticle capture membrane sample for a water flow period corresponding to the time when the product used the ultrapure water.

5. The water quality management method described in claim 4, wherein the capture film identification information uniquely assigned to the microparticle capture film is recorded in association with the water flow period, and when the analysis becomes necessary, at least one of quantitative analysis and qualitative analysis is performed on the microparticle capture film sample recorded in association with the water flow period corresponding to the time when the product used the ultrapure water.

6. 6. The water quality control method according to claim 1, wherein an integrating flow meter is provided downstream of the filtration device in the direction of flow of the ultrapure water.

7. 7. The water quality control method according to claim 1, wherein the circulation pipe is a pipe branching off from an ultrapure water production system and supplying ultrapure water to a use point, or a pipe branching off from the pipe.

8. an input unit that inputs input information based on an operation received from outside; a database that stores period information indicating the time period during which a particle capture membrane that captures particles in ultrapure water when ultrapure water is passed through the membrane has been attached to a flow pipe through which the ultrapure water flows, in association with capture membrane identification information uniquely assigned to the particle capture membrane; a search unit that searches the database for the capture membrane identification information based on date and time information included in the input information input by the input unit; an output unit that outputs the capture membrane identification information retrieved by the retrieval unit; and a notification unit that issues a predetermined notification when a predetermined period of time has elapsed since the particle capture membrane was attached to the flow pipe.

9. The information processing apparatus according to claim 8 , wherein the input unit inputs predetermined information when analysis of the ultrapure water becomes necessary after the ultrapure water has been used in a manufacturing process of a product.

10. The system includes a filtering device, an analyzing device, an information processing device, a notification unit, and a flow rate adjusting valve, The filtration device is a particle capture membrane that is detachably provided from the filtration device and captures particles of the ultrapure water when the ultrapure water is passed through the membrane; The information processing device includes: an input unit that inputs input information based on an operation received from outside; a database that stores period information indicating the time period during which the particle trapping membrane was attached to the flow pipe through which the ultrapure water flows, and trapping membrane identification information uniquely assigned to the particle trapping membrane, in association with each other; a search unit that searches the database for the capture membrane identification information based on date and time information included in the input information input by the input unit; an output unit that outputs the capture membrane identification information retrieved by the retrieval unit; The analysis device performing at least one of quantitative analysis and qualitative analysis on the particle trapping membrane to which the trapping membrane identification information output by the output unit has been assigned; the output unit outputs information to be provided based on a result of the analysis performed by the analysis device; the notification unit issues a predetermined notification when a predetermined period of time has elapsed since the particle capture membrane was attached to the flow pipe, the flow rate adjustment valve is disposed in a bypass line branching from the circulation pipe for draining the ultrapure water; After the predetermined period has elapsed, the information processing system fully opens the flow rate adjusting valve to allow the ultrapure water to flow only through the bypass line.

11. the information processing device has an extraction unit that extracts provided information, which is information corresponding to the input information, from the result of an analysis performed by the analysis device on the particle capture film to which the capture film identification information searched by the search unit has been assigned; The information processing system according to claim 10 , wherein the output unit outputs the provided information extracted by the extraction unit.

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