Apparatus for producing cleaning water for electronic device, and method for producing said cleaning water

Abstract

An apparatus for producing cleaning water for an electronic device, the apparatus comprising: a pH adjustment device for preparing pH adjustment water by adding a pH adjusting agent to ultrapure water; a deaerator for deaerating the pH adjustment water; a gas dissolution membrane type device for preparing cleaning water by dissolving a functional gas in the deaerated pH adjustment water through a gas permeable membrane; and a control device which is capable of performing control so that the ultrapure water is transferred at a flow rate of 18L / min or less.

Description

Apparatus for producing cleaning water for electronic devices and method for producing said cleaning water

[0001] The present disclosure relates to an apparatus for producing cleaning water for electronic devices and a method for producing the cleaning water.

[0002] In the manufacturing process of electronic devices such as semiconductor devices, contaminants on the surfaces of electronic devices can lead to deterioration of the performance of the electronic devices or a decrease in the yield of the manufacturing line. For this reason, the surfaces of electronic devices are cleaned using ultrapure water or cleaning water prepared by dissolving chemicals in ultrapure water. Conventionally, cleaning water prepared by dissolving ammonia, hydrogen gas, etc. in ultrapure water as raw water has been used as the cleaning water (see, for example, Patent Documents 1 to 3).

[0003] JP 10-064867 A JP 2000-354729 A JP 2018-022749 A

[0004] In recent years, with the improvement in the performance of electronic devices, there has been great progress in miniaturization of circuit fabrication technology. Because even the smallest amount of contaminants can be a problem, the amount of cleaning water used is increasing year by year. Because cleaning water is produced from ultrapure water, efforts to conserve water are required.

[0005] Cleaning water is produced, for example, by mixing a pH adjuster or dissolving a functional gas in ultrapure water. After the start of cleaning water production, it takes a certain amount of time for the cleaning water quality (e.g., pH, concentration of the active ingredient in the pH adjuster, and concentration of the functional gas) to reach the water quality required by the electronic device manufacturing process equipment (hereinafter also referred to as the "set water quality"). In electronic device manufacturing process equipment, there are times when the equipment is required to wait for the transfer of cleaning water for various reasons. If cleaning water production is stopped each time, time is required for the cleaning water quality to reach the set water quality.

[0006] Therefore, in a cleaning water production apparatus that transfers cleaning water to the above-mentioned process equipment, an idling operation is sometimes performed in which cleaning water having the above-mentioned set water quality is produced without being transferred to the above-mentioned process equipment. The cleaning water produced during this idling operation is not transferred to the above-mentioned process equipment, and in some cases is treated as wastewater. An object of the present disclosure is to provide an electronic device cleaning water production apparatus that can reduce the amount of cleaning water treated as wastewater.

[0007] One aspect of the apparatus for producing cleaning water for electronic devices according to the present disclosure includes: a pH adjusting device that adds a pH adjuster to ultrapure water to prepare pH-adjusted water; a degassing device that degasses the pH-adjusted water; a gas-dissolving membrane type apparatus that prepares cleaning water by dissolving a functional gas in the degassed pH-adjusted water via a gas-permeable membrane; and a control device that can control the transfer of the ultrapure water at a flow rate of 18 L / min or less.

[0008] The electronic device cleaning water manufacturing apparatus of the present disclosure can, for example, reduce the amount of cleaning water treated as wastewater. In one embodiment, the manufacturing apparatus can produce cleaning water at a low flow rate during standby time when cleaning water is not being transferred to its use point, and can produce cleaning water at the flow rate required at the use point during operating time when cleaning water is being transferred to its use point (hereinafter also referred to as "main operating time"). The standby time is the time required for waiting for the transfer of cleaning water from the electronic device manufacturing process equipment, which is the cleaning water use point. During this standby time, the cleaning water manufacturing apparatus can be said to be idling. The manufacturing apparatus of the present disclosure can reduce the amount of cleaning water produced during idling operation, and can reduce the amount of cleaning water treated as wastewater.

[0009] Fig. 1 is a block diagram showing an outline of an embodiment of a cleaning water production device. Fig. 2 is a block diagram showing an outline of an embodiment of a cleaning water production device. Fig. 3 is a block diagram showing an outline of an embodiment of a cleaning water production device.

[0010] In this specification, the numerical range N1 to N2 means N1 or more and N2 or less. In this specification, when the units of the numerical values ​​written before and after "to" indicating a numerical range are the same, the unit of the numerical value written before "to" may be omitted.

[0011] [Apparatus for Producing Cleaning Water for Electronic Devices] Embodiments of the present disclosure will now be described in detail with reference to the drawings. The apparatus for producing cleaning water for electronic devices of the present disclosure (hereinafter also simply referred to as the "production apparatus of the present disclosure") includes a pH adjuster that adds a pH adjuster to ultrapure water to prepare pH-adjusted water, a degassing apparatus that degasses the pH-adjusted water, a gas-dissolved membrane type apparatus that prepares cleaning water by dissolving a functional gas in the degassed pH-adjusted water via a gas-permeable membrane, and a control device that can control the transfer of the ultrapure water at a flow rate of 18 L / min or less.

[0012] The manufacturing apparatus of the present disclosure produces cleaning water for electronic devices from ultrapure water. Ultrapure water is produced, for example, by removing ionic substances, organic matter, dissolved gases, and particulates from raw water. Examples of raw water include city water, well water, river water, lake water, and industrial water. For example, ultrapure water preferably has a resistivity of 18.1 MΩ·cm or more, particulates with a particle size of 50 nm or more and 1,000 particles / L or less, viable bacteria of 1 / L or less, total organic carbon (TOC) of 1 μg / L or less, total silicon of 0.1 μg / L or less, metals of 1 ng / L or less, ions of 10 ng / L or less, hydrogen peroxide of 30 μg / L or less, and a water temperature of 25±2°C, but is not particularly limited thereto.

[0013] The cleaning water for electronic devices (hereinafter simply referred to as "cleaning water") produced using the manufacturing apparatus of the present disclosure is transported to a point of use (UP), such as a cleaning apparatus provided in an electronic device manufacturing process for manufacturing semiconductor devices or the like.

[0014] The manufacturing apparatus of the present disclosure includes a transfer line through which ultrapure water, pH-adjusted water, or cleaning water (hereinafter also referred to as "ultrapure water, etc.") flows. The manufacturing apparatus of the present disclosure includes a pH adjuster, a degasser, and a gas-dissolved membrane device, in this order, on the transfer line. The ultrapure water as raw water flowing through the transfer line passes through the pH adjuster to become pH-adjusted water, the pH-adjusted water passes through the degasser to be degassed, and the degassed pH-adjusted water passes through the gas-dissolved membrane device to become cleaning water.

[0015] The manufacturing apparatus of the present disclosure preferably further comprises a switching device for switching the flow path of the cleaning water, located on the transfer line downstream of the gas dissolved film device. At the switching device, the transfer line branches into, for example, a transfer line connected to a use point of the cleaning water, and a drain line for draining the cleaning water, or a circulation line that joins the transfer line at a junction located upstream of the transfer line and uses the circulated cleaning water.

[0016] <Flow paths> In the manufacturing apparatus of the present disclosure, the flow paths (e.g., transfer lines or supply lines) through which ultrapure water, pH-adjusted water, cleaning water, pH adjuster, oxidation-reduction potential adjuster, functional gas, etc. flow are configured, for example, with piping. The flow paths may be provided with equipment such as tanks, pumps, joints, and valves.

[0017] Examples of materials for piping include polymeric materials such as polyvinyl chloride (PVC), polyphenylene sulfide (PPS), polyvinylidene fluoride (PVDF), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and polypropylene (PP); as well as fiber-reinforced plastic (FRP) and stainless steel. Among these, PVDF is preferred. The inner diameter of the piping that constitutes the transfer line is, for example, 4 to 200 mm, preferably 6 to 100 mm, and more preferably 10 to 50 mm.

[0018] <pH Adjustment Device> The manufacturing apparatus of the present disclosure includes a pH adjustment device that adds a pH adjuster to ultrapure water to prepare pH-adjusted water. The pH adjustment device is an apparatus that measures and supplies the pH adjuster to a transfer line for ultrapure water to prepare pH-adjusted water having a desired pH. The pH adjustment device includes, for example, a tank containing the pH adjuster, a supply line that supplies the pH adjuster from the tank to the transfer line, and, if desired, a pump that adjusts the supply rate of the pH adjuster.

[0019] The pH-adjusted water obtained by adding a pH adjuster to ultrapure water has a higher electrical conductivity than ultrapure water, which can prevent charging of the pipes and the liquid flowing through them, and can prevent particles from being mixed into the cleaning water.

[0020] The tank containing the pH adjuster may be equipped with at least one device selected from the group consisting of a device for purging the inside of the tank with an inert gas (e.g., N2 gas) and a degassing membrane for removing dissolved gas (e.g., dissolved oxygen) in the pH adjuster in the tank.

[0021] The pump may be, for example, a diaphragm pump. Alternatively, a pressure extrusion pump may be used, in which the pH adjuster is placed in a tank together with an inert gas (e.g., N2 gas) and the pH adjuster is extruded by the pressure of the inert gas.

[0022] When adjusting the pH of ultrapure water to 7 or higher, examples of the pH adjuster include an aqueous solution of an alkaline compound and a gaseous alkaline compound. The alkaline compound is the active ingredient of the pH adjuster. Examples of the alkaline compound include ammonia, tetramethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, sodium hydroxide, and potassium hydroxide. Examples of the gaseous alkaline compound include ammonia gas. One type of alkaline compound may be used, or two or more types may be used.

[0023] Among these, an aqueous ammonia solution or ammonia gas is preferred, and an aqueous ammonia solution is more preferred. By dissolving a small amount of ammonia in ultrapure water, for example, the effect of suppressing dissolution and charging of semiconductor materials can be obtained.

[0024] The concentration of an alkaline compound (e.g., ammonia) in the pH-adjusted water obtained by the pH adjuster is preferably 2 to 100 mg / L, more preferably 5 to 80 mg / L, and even more preferably 10 to 50 mg / L. When an aqueous ammonia solution is used as the pH adjuster, the aqueous ammonia solution is preferably added so that the ammonia concentration in the pH-adjusted water is 2 to 100 mg / L.

[0025] When adjusting the pH of ultrapure water to less than 7, examples of pH adjusters include aqueous solutions of acidic compounds such as hydrochloric acid, nitric acid, sulfuric acid, formic acid, acetic acid, and citric acid, as well as gases such as CO2 gas. The acidic compounds and carbon dioxide gas (CO2 gas) are active ingredients of the pH adjuster. One or more types of acidic compounds may be used.

[0026] The pH adjuster is preferably a liquid, more preferably an aqueous solution of an alkaline compound, and even more preferably an aqueous ammonia solution. The mass concentration of the alkaline compound in the aqueous solution of the pH adjuster, for example, the mass concentration of the aqueous ammonia solution, is not particularly limited, but is preferably 20 to 40%, more preferably 25 to 30%.

[0027] When the pH adjuster is a gas, a direct gas-liquid contact device such as a gas permeable membrane module or an ejector may be used as the pH adjuster.

[0028] In one embodiment, the pH adjuster prepares pH-adjusted water having a pH of preferably 8 to 11, more preferably 9 to 11. A pH of 8 or higher tends to suppress the generation of static electricity in various devices located downstream of the pH adjuster. A pH of 11 or lower tends to suppress corrosion of the surface to be cleaned and deterioration of membranes and the like included in degassing devices or gas-dissolved membrane devices.

[0029] The supply rate (flow rate) of the pH adjuster in the pH adjuster can be calculated, for example, from the set concentration of the active ingredient of the pH adjuster in the cleaning water, the concentration of the active ingredient in the pH adjuster, and the transfer rate (flow rate) of the ultrapure water. The set concentration of the active ingredient of the pH adjuster in the cleaning water means the concentration of the active ingredient in the cleaning water required at the point of use of the cleaning water, such as in electronic device manufacturing process equipment.

[0030] In one embodiment, the pH adjustment device can change the flow rate of the pH adjuster depending on the flow rate of ultrapure water, etc. during the standby time or main operation time of cleaning water production. The manufacturing device of the present disclosure can produce cleaning water without significantly changing the water quality (e.g., pH, concentration of the active ingredient of the pH adjuster) even if, for example, the flow rate of ultrapure water, etc. during the main operation time is several to several tens of times higher than the flow rate during the standby time, i.e., even when the standby time is followed by a transition to the main operation time by changing the flow rate several to several tens of times.

[0031] <Oxidation-Reduction Potential Adjusting Device> The manufacturing apparatus of the present disclosure may further include an oxidation-reduction potential adjusting device (hereinafter also referred to as "ORP adjusting device") that adjusts the oxidation-reduction potential (hereinafter also referred to as "ORP adjusting device") of the ultrapure water or pH-adjusted water. The ORP adjusting device is preferably located downstream of the pH adjusting device and upstream of the degassing device on the transfer line. Therefore, the ORP of the pH-adjusted water may be adjusted by the ORP adjusting device.

[0032] The ORP adjuster is a device that adjusts the ORP of ultrapure water or pH-adjusted water by measuring and supplying an oxidation-reduction potential adjuster (hereinafter also referred to as "ORP adjuster") to the transfer line. The ORP adjuster includes, for example, a tank containing the ORP adjuster, a supply line that supplies the ORP adjuster from the tank to the transfer line, and, if desired, a pump that adjusts the supply rate of the ORP adjuster.

[0033] The tank containing the ORP adjuster may be equipped with at least one device selected from the group consisting of a device for purging the inside of the tank with an inert gas (e.g., N2 gas) and a degassing membrane for removing dissolved gas (e.g., dissolved oxygen) from the ORP adjuster in the tank.

[0034] The pump may be, for example, a diaphragm pump. Alternatively, a pressure extrusion pump may be used, in which the ORP adjuster is placed in a tank together with an inert gas (e.g., N2 gas) and the pressure of the inert gas is used to extrude the ORP adjuster.

[0035] Examples of ORP adjusters that adjust the oxidation-reduction potential of the target water higher (positive side) include aqueous solutions such as hydrogen peroxide solution, and gases such as ozone gas and oxygen gas. Examples of ORP adjusters that adjust the oxidation-reduction potential of the target water lower include aqueous solutions of compounds such as oxalic acid, hydrogen sulfide, and potassium iodide, and gases such as hydrogen gas. One or more of the above compounds may be used. One or more of the above gases may be used.

[0036] When the ORP adjuster is a gas, a direct gas-liquid contact device such as a gas permeable membrane module or an ejector may be used as the ORP adjuster.

[0037] The supply rate (flow rate) of the ORP adjuster in the ORP adjuster can be calculated, for example, from the set concentration of the active ingredient of the ORP adjuster in the cleaning water, the concentration of the active ingredient in the ORP adjuster, and the transfer rate (flow rate) of the ultrapure water or pH-adjusted water. The set concentration of the active ingredient of the ORP adjuster in the cleaning water means the concentration of the active ingredient in the cleaning water required at the point of use of the cleaning water, such as in electronic device manufacturing process equipment.

[0038] In one embodiment, the ORP adjusting device can change the flow rate of the ORP adjuster depending on the flow rate of ultrapure water, etc. during the standby time or main operation time of cleaning water production. The manufacturing device of the present disclosure can produce cleaning water without significantly changing the water quality (e.g., ORP, concentration of the active ingredient of the ORP adjuster) even if, for example, the flow rate of ultrapure water, etc. during the main operation time is several to several tens of times higher than the flow rate during the standby time, i.e., even when the standby time is followed by a transition to the main operation time by changing the flow rate several to several tens of times.

[0039] <Hydrogen Peroxide Removal Device> The manufacturing apparatus of the present disclosure may further include a hydrogen peroxide removal device. For example, it is preferable that at least a portion of the hydrogen peroxide has been removed from the ultrapure water or pH-adjusted water to which the ORP adjuster is supplied. Therefore, the hydrogen peroxide removal device is preferably located upstream of the ORP adjuster on the transfer line, and more preferably upstream of the pH adjuster and the ORP adjuster. By providing the hydrogen peroxide removal device, the ORP adjuster can accurately control the ORP of the cleaning water.

[0040] The hydrogen peroxide removal device includes, for example, a platinum group metal-supported resin column. The platinum group metal-supported resin column includes a resin (hereinafter also referred to as "support resin") and a platinum group metal supported on the resin. Examples of the support resin include ion exchange resins. Among ion exchange resins, anion exchange resins are preferred. Platinum group metals are negatively charged, so they are stably supported on anion exchange resins and are less likely to fall off. The exchange groups of the anion exchange resin are preferably in the OH form. OH-form anion exchange resins have an alkaline resin surface, which promotes the decomposition of hydrogen peroxide. Examples of platinum group metals include ruthenium, rhodium, palladium, osmium, iridium, and platinum. Platinum group metals may be used alone or in combination, or as an alloy of two or more metals. Purified products of naturally occurring mixtures may also be used without separating them into individual elements. Among these, platinum, palladium, platinum / palladium alloys, or mixtures of two or more of these, are preferably used because of their strong catalytic activity. Nano-sized particles of these metals can also be preferably used.

[0041] <Pump> The manufacturing apparatus of the present disclosure may further include a pump. By using a pump, it becomes easier to increase the flow rate and water pressure of ultrapure water or the like, thereby producing cleaning water. The pump, for example, pressurizes ultrapure water or the like to a predetermined water pressure. The pump is preferably a pump that can control the amount of pressure applied. The manufacturing apparatus of the present disclosure preferably includes a pump on the transfer line between the pH adjuster and the degassing device. If the manufacturing apparatus includes an ORP adjuster, it is preferable to include a pump between the ORP adjuster and the degassing device.

[0042] Examples of pumps include rotary positive displacement pumps that continuously suck in and discharge by changing the volume, reciprocating positive displacement pumps that repeatedly suck in and discharge by changing the volume, and centrifugal pumps that discharge liquid by using centrifugal force or thrust generated by the rotation of an impeller or propeller inside the pump.

[0043] Examples of rotary positive displacement pumps include tube pumps, rotary pumps, gear pumps, and snake pumps. Examples of reciprocating positive displacement pumps include diaphragm pumps and plunger pumps. Examples of centrifugal pumps include volute pumps. Among these, rotary positive displacement pumps and centrifugal pumps are preferred, centrifugal pumps are more preferred, and volute pumps, which are centrifugal pumps, are even more preferred, in that they cause less fluid pulsation and maintain a substantially constant and stable discharge pressure.

[0044] The pressure of the ultrapure water, pH-adjusted water, or cleaning water pressurized by the pump is preferably 0.1 MPa or higher, more preferably 0.2 to 1.0 MPa, even more preferably 0.2 to 0.8 MPa, and particularly preferably 0.2 to 0.6 MPa. If the pressure is 0.1 MPa or higher, a sufficient flow rate of the ultrapure water, pH-adjusted water, or cleaning water is easily obtained. If the pressure is 1.0 MPa or lower, static electricity is less likely to be generated within the pump.

[0045] <Degassing Device> The manufacturing apparatus of the present disclosure includes a degassing device that degasses the pH-adjusted water. The degassing device removes at least a portion of the dissolved gases in the pH-adjusted water to reduce the amount of dissolved gas. This removal can increase the solubility of functional gases in the pH-adjusted water, for example, in a gas-dissolved film type apparatus. Examples of dissolved gases include dissolved oxygen and dissolved nitrogen.

[0046] The degassing device is preferably located downstream of the pH adjuster or downstream of the pH adjuster and ORP adjuster on the transfer line. Although this manufacturing system includes a degassing device, it can suppress static electricity and prevent fine particles from accumulating on the gas-permeable membrane surface. This prevents fine particles from getting into the cleaning water.

[0047] The degassing device is preferably a membrane degassing device, and more preferably a membrane degassing device equipped with a gas-permeable membrane. In one embodiment, the membrane degassing device flows pH-adjusted water through one side (liquid phase chamber) of the gas-permeable membrane and reduces the pressure on the other side (gas phase chamber) with a vacuum pump, thereby causing at least a portion of the dissolved gas to permeate through the gas-permeable membrane and migrate to the gas phase chamber for removal. The degassing device, for example, reduces the dissolved oxygen concentration in the pH-adjusted water supplied to the gas-dissolved membrane device to 0.1 mg / L or less.

[0048] The gas-permeable membrane may be any membrane that allows gases such as oxygen, nitrogen, and steam to pass through but does not allow water to pass through. Examples of materials constituting the gas-permeable membrane include polymeric materials such as silicone rubber, polytetrafluoroethylene, polyvinylidene fluoride, polyolefins (e.g., polypropylene and poly(4-methylpentene-1)), and polyurethane. One type of polymeric material may be used, or two or more types may be used. Among these, at least one selected from the group consisting of poly(4-methylpentene-1), polypropylene, and polyvinylidene fluoride is preferred.

[0049] <Gas-Dissolved Film Type Apparatus> The manufacturing apparatus of the present disclosure includes a gas-dissolved film type apparatus. The gas-dissolved film type apparatus is preferably located downstream of the degassing device on the transfer line. The gas-dissolved film type apparatus dissolves a functional gas in degassed pH-adjusted water via a gas-permeable membrane.

[0050] A functional gas is a gas that imparts a specific function to cleaning water. Examples of functional gases include hydrogen gas, ozone gas, carbon dioxide gas, and rare gases. Among these, hydrogen gas is preferred. The concentration of hydrogen gas in cleaning water obtained using a gas-dissolved film type device is preferably 1.0 to 1.6 mg / L. By using cleaning water in which hydrogen gas is dissolved, a good effect of removing particulates from electronic devices can be obtained. One type of functional gas may be used, or two or more types may be used.

[0051] The functional gas is supplied from a functional gas supply device. The functional gas supply device includes, for example, a functional gas storage device that generates or stores the functional gas and a mass flow controller that adjusts the supply rate of the functional gas. The functional gas supply device is connected to the gas dissolved film type device by a functional gas supply line and supplies the functional gas to the gas dissolved film type device.

[0052] The supply rate (flow rate) of the functional gas in the functional gas supply device can be calculated, for example, from the set concentration of the functional gas in the cleaning water and the transfer rate (flow rate) of the degassed pH-adjusted water. The set concentration of the functional gas in the cleaning water means the concentration of the functional gas in the cleaning water required at the point of use of the cleaning water, such as in an electronic device manufacturing process equipment.

[0053] In one embodiment, the functional gas supply device can change the flow rate of the functional gas depending on the flow rate of ultrapure water, etc. during the standby time or main operation time of cleaning water production. The manufacturing device of the present disclosure can produce cleaning water without significantly changing the water quality (e.g., the concentration of the functional gas) even if, for example, the flow rate of ultrapure water, etc. during the main operation time is several to several tens of times higher than the flow rate during the standby time, i.e., even when the standby time is followed by a transition to the main operation time by changing the flow rate several to several tens of times.

[0054] In one embodiment, the gas-dissolved membrane device flows degassed pH-adjusted water on one side (liquid phase chamber) of a gas-permeable membrane and supplies a functional gas to the other side (gas phase chamber), allowing the functional gas to permeate the gas-permeable membrane, migrate to the liquid phase chamber, and dissolve in the pH-adjusted water.

[0055] Examples of materials constituting the gas-permeable membrane are as described above, and will not be further illustrated in this section. Among the above materials, at least one selected from the group consisting of poly(4-methylpentene-1), polypropylene, and polyvinylidene fluoride is preferred.

[0056] The gas-permeable membrane may be, for example, a hollow fiber membrane. In this case, the gas-dissolved membrane device includes a hollow fiber membrane unit containing a hollow fiber membrane. Connected to the interior of the hollow fiber membrane unit are a liquid supply pipe for supplying degassed pH-adjusted water to the hollow fiber membrane unit, a gas supply pipe for supplying a functional gas to the hollow fiber membrane unit, and a drain pipe for discharging the cleaning water in which the functional gas has been dissolved.

[0057] <Control Device> The manufacturing apparatus of the present disclosure is equipped with a control device capable of controlling the transfer of ultrapure water, etc., at a flow rate of 18 L / min or less. The raw water, i.e., ultrapure water, pH-adjusted water, and cleaning water, are transferred via transfer lines. The control device can control the transfer line to deliver water at a flow rate of 18 L / min or less, preferably 0.1 to 18 L / min, more preferably 0.3 to 17 L / min, even more preferably 0.5 to 16 L / min, and particularly preferably 0.8 to 15.5 L / min. In the manufacturing apparatus of the present disclosure, the flow rate of ultrapure water, etc., is preferably set within the above range. This reduces the amount of cleaning water treated as wastewater.

[0058] In one embodiment, the control device controls the flow rate of ultrapure water or the like during standby time when cleaning water is not being transferred to the use point so that it is smaller than the flow rate of ultrapure water or the like required during the main operation time when cleaning water is being transferred to the use point. Such control makes it possible to reduce the amount of cleaning water treated as wastewater during standby time. The value obtained by subtracting the flow rate of ultrapure water or the like during standby time from the flow rate of ultrapure water or the like required during the main operation time is preferably more than 0 L / min and 17 L / min or less, more preferably 0.5 to 16 L / min, and even more preferably 0.8 to 15 L / min.

[0059] The control device controls the flow rate of the ultrapure water or the like during the standby time to preferably 0.1 to 17 L / min, more preferably 0.3 to 10 L / min, even more preferably 0.5 to 6 L / min, and particularly preferably 0.8 to 4 L / min. By such control, the amount of cleaning water treated as wastewater during the standby time can be reduced.

[0060] In the production apparatus of the present disclosure, the absolute value of the rate of change of the pH (or ORP) of cleaning water produced during the main operation time, based on the pH (or ORP) of cleaning water produced during the standby time, is preferably 10% or less, more preferably 5% or less, even more preferably 3% or less, and particularly preferably 1% or less. The production apparatus of the present disclosure can produce cleaning water without a large change in pH or ORP, even when the flow rate of ultrapure water or the like is changed from the standby time to the main operation time by several to several tens of times.

[0061] In the manufacturing apparatus of the present disclosure, the absolute value of the rate of change in the concentration of the functional gas in the cleaning water produced during the main operation time, based on the concentration of the functional gas in the cleaning water produced during the standby time, is preferably 10% or less, more preferably 5% or less, even more preferably 3% or less, and particularly preferably 1% or less. The manufacturing apparatus of the present disclosure can produce cleaning water without a significant change in the concentration of the functional gas, even when the flow rate of ultrapure water or the like is changed from the standby time to the main operation time by several to several tens of times.

[0062] The control device is, for example, a computer.

[0063] The control device may be, for example, electrically or wirelessly connected to a pump that adjusts the flow rate of, for example, ultrapure water, pH-adjusted water, or cleaning water.

[0064] The control device may control at least one selected from the group consisting of the pH adjuster supply rate in the pH adjuster and the functional gas supply rate in the gas dissolved film device, for example, in response to changes in the flow rate of ultrapure water or based on the water quality or flow rate measured by a cleaning water monitoring device described below. Preferably, it may control at least one selected from the group consisting of the pH adjuster supply rate, the ORP adjuster supply rate in the ORP adjuster, and the functional gas supply rate. The control device can control the cleaning water to have at least one selected from the group consisting of a set concentration of the active ingredient, a set pH value, a set ORP value, and a set concentration of the functional gas. The control of at least one selected from the group consisting of the active ingredient concentration, pH, ORP, and functional gas concentration by such a control device can be controlled by feedback control such as PI control or PID control, as well as by known methods.

[0065] The control device can transmit a signal to the pH adjustment device or the ORP adjustment device in response to a change in the flow rate of the ultrapure water, etc., or based on the water quality (e.g., the concentration of the active ingredient of the pH adjuster or the pH) or flow rate measured by the cleaning water monitoring device, and control the supply rate of the pH adjuster in the pH adjustment device or the ORP adjuster in the ORP adjustment device using a pump, etc. The control device can transmit a signal to the functional gas mass flow controller in response to a change in the flow rate of the ultrapure water, etc., or based on the water quality (e.g., the concentration of the functional gas) or flow rate measured by the cleaning water monitoring device, and control the supply rate of the functional gas supplied from the functional gas supply device using a mass flow controller, etc.

[0066] The control device is preferably a device that further controls the flow path of the cleaning water. The function of controlling the flow rate of ultrapure water or the like, the function of controlling at least one selected from the group consisting of the supply rate of a pH adjuster in the pH adjuster and the supply rate of a functional gas in the gas dissolved film type device, and the function of controlling the flow path of the cleaning water may be performed by the same control device or by different control devices.

[0067] In one embodiment, the control device controls the switching device for the cleaning water flow path so that during standby time, the cleaning water is not transferred to the use point, but rather, for example, transferred to a drain line or a circulation line; and during main operation time, the control device controls the switching device to transfer the cleaning water to the use point by sending a signal to the switching device and switching the cleaning water flow path.

[0068] <Water Quality or Flow Rate Monitoring Device> The manufacturing apparatus of the present disclosure preferably further includes a water quality monitoring device for the cleaning water. The water quality monitoring device is a device for measuring the quality of the cleaning water. The water quality monitoring device is preferably located downstream of the gas dissolved film device on the transfer line. The water quality monitoring device measures, for example, at least one selected from the group consisting of the concentration of the active ingredient of a pH adjuster and the concentration of a functional gas in the cleaning water, and preferably measures at least one selected from the group consisting of the concentration of the active ingredient of a pH adjuster, the concentration of the active ingredient of an ORP adjuster, pH, oxidation-reduction potential (ORP), and the concentration of a functional gas in the cleaning water, and monitors whether the concentration of the active ingredient, pH, ORP, or the concentration of the functional gas is at a desired value.

[0069] The pH of the cleaning water can be measured using a known pH meter. The ORP of the cleaning water can be measured using a known ORP meter. The concentration of the active ingredient in the cleaning water can be measured using a known conductivity meter. The concentration of the functional gas in the cleaning water can be measured using a known gas concentration meter (e.g., a DH meter for hydrogen gas).

[0070] The manufacturing apparatus of the present disclosure preferably further includes a flow rate monitor for the cleaning water. The flow rate monitor is a device for measuring the flow rate of the cleaning water. The flow rate monitor is preferably located downstream of the gas dissolved film device on the transfer line. Examples of the flow rate monitor include a known flow meter.

[0071] The water quality monitoring device or the flow rate monitoring device may be connected to the control device, for example, electrically or wirelessly. The control device may be connected to at least one device selected from the group consisting of a pH adjusting device, an ORP adjusting device, and a gas dissolved film device, for example, electrically or wirelessly.

[0072] <Device for switching the flow path of cleaning water> The manufacturing apparatus of the present disclosure preferably further includes a device for switching the flow path of cleaning water (flow path switching device) between the gas dissolved film device and the use point of cleaning water, preferably between the monitoring device and the use point of cleaning water. The switching device is preferably located downstream of the water quality monitoring device on the transfer line. An example of such a device is a three-way switching valve.

[0073] The transfer line branches at the switching device into, for example, a transfer line connected to the point of use of cleaning water, and a drainage line for draining cleaning water, or a circulation line for circulating and using cleaning water, which joins at a junction located upstream on the transfer line. Circulating cleaning water can reduce the amount of produced cleaning water discharged. The junction is located, for example, upstream of a pH adjustment device or a hydrogen peroxide removal device on the transfer line. The switching device switches the flow path of cleaning water based on a signal sent from the control device or manually, thereby transferring cleaning water to the point of use.

[0074] 1 to 3 are block diagrams schematically illustrating a manufacturing apparatus according to the present disclosure. The manufacturing apparatus 1 in FIG. 1 includes a transfer line L1 for ultrapure water W, pH-adjusted water W1, or cleaning water W2, a pH adjuster 12, a degassing device 14, a gas-dissolved film device 16, a water quality or flow rate monitoring device 18, and a control device 22. The transfer line L1 connects the pH adjuster 12 and the degassing device 14, connects the degassing device 14 and the gas-dissolved film device 16, and connects the gas-dissolved film device 16 and the monitoring device 18. The manufacturing apparatus 1 in FIG. 1 further includes a pump P1 on the transfer line L1 between the pH adjuster 12 and the degassing device 14 for adjusting the flow rate of the ultrapure water or the like.

[0075] The manufacturing apparatus 1 in Fig. 2 includes a transfer line L1, a pH adjusting device 12, a degassing device 14, a gas dissolved film device 16, a water quality or flow rate monitoring device 18, a cleaning water flow path switching device 20, a control device 22, a transfer line L2, and a drain line L3. The manufacturing apparatus 1 in Fig. 2 further includes a pump P1 on the transfer line L1 between the pH adjusting device 12 and the degassing device 14 for adjusting the flow rate of ultrapure water or the like.

[0076] The transfer line L1 connects the pH adjusting device 12 and the degassing device 14, connects the degassing device 14 and the gas dissolved film type device 16, connects the gas dissolved film type device 16 and the monitoring device 18, and connects the monitoring device 18 and the switching device 20. The transfer line L2 connects the switching device 20 and the point of use (UP).

[0077] The production apparatus 1 in Figure 3 includes a transfer line L1, a hydrogen peroxide remover 11, a pH adjuster 12, an ORP adjuster 13, a degasser 14, a gas dissolved film device 16, a water quality or flow rate monitor 18, a cleaning water flow path switching device 20, a control device 22, a transfer line L2, and a drain line L3. The production apparatus 1 in Figure 3 further includes a pump P1 on the transfer line L1 between the ORP adjuster 13 and the degasser 14 for adjusting the flow rate of ultrapure water or the like.

[0078] 1 to 3, the control device 22 controls the pump P1 to control the flow rate of the ultrapure water, etc. Based on the water quality or flow rate obtained by the monitoring device 18, the control device 22 controls the supply rate of the pH adjuster in the pH adjuster 12 and the supply rate of the functional gas supplied to the gas dissolved film type device 16.

[0079] 1 to 3, pH adjuster 12 includes tank 12A containing a pH adjuster, supply line 12L connecting tank 12A to transfer line L1, and pump 12B located on supply line 12L. In Fig. 3, ORP adjuster 13 includes tank 13A containing an ORP adjuster, supply line 13L connecting tank 13A to transfer line L1, and pump 13B located on supply line 13L. In Fig. 1 to 3, gas dissolved film type device 16 is connected to functional gas supply device 16A via supply line 16L.

[0080] 2 and 3, a circulation line (not shown) for circulating the cleaning water for reuse may be provided. The circulation line merges with the transfer line L1 at a junction located upstream of the pH adjuster 12, for example.

[0081] The cleaning water manufacturing apparatus of the present disclosure has been described above based on the above embodiment with reference to the attached drawings, but the cleaning water manufacturing apparatus of the present disclosure is not limited to the above embodiment and various modifications can be made.

[0082] [Method for Producing Cleaning Water for Electronic Devices] The method for producing cleaning water for electronic devices of the present disclosure (hereinafter also simply referred to as the "production method of the present disclosure") includes a pH adjustment step of adding a pH adjuster to ultrapure water to prepare pH-adjusted water, a degassing step of degassing the pH-adjusted water, and a gas dissolution step of dissolving a functional gas in the degassed pH-adjusted water via a gas-permeable membrane to prepare cleaning water. The production method of the present disclosure may further include at least one step selected from the group consisting of an ORP adjustment step of adjusting the oxidation-reduction potential (ORP) of the ultrapure water or the pH-adjusted water, and a hydrogen peroxide removal step of removing hydrogen peroxide. The production method of the present disclosure can be carried out, for example, using the production apparatus described above.

[0083] In the above production method, the ultrapure water, pH-adjusted water, or cleaning water is transferred at a flow rate of, for example, 18 L / min or less, preferably 0.1 to 18 L / min, more preferably 0.3 to 17 L / min, even more preferably 0.5 to 16 L / min, and particularly preferably 0.8 to 15.5 L / min.

[0084] The above production method preferably further comprises a step of adjusting the pressure of the ultrapure water, pH-adjusted water, or cleaning water to 0.1 MPa or more. The pressure is preferably 0.1 MPa or more, more preferably 0.2 to 1.0 MPa, even more preferably 0.2 to 0.8 MPa, and particularly preferably 0.2 to 0.6 MPa.

[0085] In the above-described manufacturing method, it is preferable to control the flow rate of ultrapure water, etc., during a standby time when cleaning water is not being transferred to the use point so as to be smaller than the flow rate of ultrapure water, etc., required during the main operation time when cleaning water is being transferred to the use point. The value obtained by subtracting the flow rate of ultrapure water, etc., during the standby time from the flow rate of ultrapure water, etc., required during the main operation time is preferably more than 0 L / min and not more than 17 L / min, more preferably 0.5 to 16 L / min, and even more preferably 0.8 to 15 L / min.

[0086] In the above manufacturing method, the flow rate of ultrapure water or the like during the waiting time is controlled to preferably 0.1 to 17 L / min, more preferably 0.3 to 10 L / min, even more preferably 0.5 to 6 L / min, and particularly preferably 0.8 to 4 L / min.

[0087] In the above-mentioned production method, the absolute value of the rate of change of the pH (or ORP) of the cleaning water produced during the main operation time based on the pH (or ORP) of the cleaning water produced during the standby time is preferably 10% or less, more preferably 5% or less, even more preferably 3% or less, and particularly preferably 1% or less.

[0088] In the above-described manufacturing method, the absolute value of the rate of change of the concentration of the functional gas in the cleaning water produced during the main operation time, based on the concentration of the functional gas in the cleaning water produced during the standby time, is preferably 10% or less, more preferably 5% or less, even more preferably 3% or less, and particularly preferably 1% or less.

[0089] In one embodiment of the above manufacturing method, during standby time, the cleaning water is not transferred to the use point, but is transferred to a drain line or a circulation line, for example; during main operation time, the cleaning water is transferred to the use point.

[0090] Regarding the details of the above production method and the conditions of each step, the conditions described in the above section [Apparatus for producing cleaning water for electronic devices] can be applied, and description thereof will be omitted here.

[0091] The cleaning water produced by the manufacturing apparatus or manufacturing method of the present disclosure is supplied to a cleaning apparatus provided in a process apparatus for manufacturing electronic devices such as semiconductor devices. Examples of the cleaning apparatus include a cleaning apparatus that immerses an object to be cleaned in cleaning water in a cleaning tank to clean it, and a cleaning apparatus that sprays cleaning water onto the object in a shower-like manner and washes it by letting it flow over the object.

[0092] [Example Aspects] The present disclosure relates to, for example, the following [1] to

[16] . [1] An apparatus for producing cleaning water for electronic devices, comprising: a pH adjuster that adds a pH adjuster to ultrapure water to prepare pH-adjusted water; a degassing apparatus that degasses the pH-adjusted water; a gas-dissolved membrane apparatus that prepares cleaning water by dissolving a functional gas in the degassed pH-adjusted water via a gas-permeable membrane; and a control device that can control the transfer of the ultrapure water at a flow rate of 18 L / min or less. [2] The apparatus for producing cleaning water for electronic devices according to [1] above, further comprising a pump that adjusts the pressure of the pH-adjusted water to 0.1 MPa or more. [3] The apparatus for producing cleaning water for electronic devices according to [1] or [2] above, wherein the control device controls the flow rate of the ultrapure water during a standby time when the cleaning water is not being transferred to its use point to be lower than the flow rate of the ultrapure water required during an operating time when the cleaning water is being transferred to the use point. [4] The apparatus for producing cleaning water for electronic devices according to [3] above, wherein the control device controls the flow rate of the ultrapure water during the standby time to 0.1 to 17 L / min. [5] The apparatus for producing cleaning water for electronic devices according to [3] or [4] above, wherein a value obtained by subtracting the flow rate of the ultrapure water during the standby time from the flow rate of the ultrapure water required during the operating time is more than 0 L / min and not more than 17 L / min. [6] The apparatus for producing cleaning water for electronic devices according to any one of [3] to [5] above, wherein an absolute value of a rate of change in pH of the cleaning water produced during the operating time, based on the pH of the cleaning water produced during the standby time, is 10% or less, and an absolute value of a rate of change in concentration of the functional gas in the cleaning water produced during the operating time, based on the concentration of the functional gas in the cleaning water produced during the standby time, is 10% or less.[7] The apparatus for producing cleaning water for electronic devices according to any one of [3] to [6], further comprising a switching device for switching the flow path of the cleaning water, wherein the transfer line through which the cleaning water flows is branched at the switching device into a transfer line connected to a use point of the cleaning water and a drain line for draining the cleaning water, and the control device controls the switching device to transfer the cleaning water to the drain line during the standby time, and controls the switching device to transfer the cleaning water to the use point during the operating time. [8] The apparatus for producing cleaning water for electronic devices according to any one of [1] to [7], wherein the pH adjustment device prepares pH-adjusted water having a pH of 8 to 11. [9] The apparatus for producing cleaning water for electronic devices according to any one of [1] to [8], wherein the pH adjustment device adds an aqueous solution of at least one alkaline compound selected from the group consisting of ammonia, tetramethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, sodium hydroxide, and potassium hydroxide to the ultrapure water as the pH adjuster.

[10] The apparatus for producing cleaning water for electronic devices according to any one of [1] to [9], wherein the functional gas is at least one selected from the group consisting of hydrogen gas, ozone gas, carbon dioxide gas, and a rare gas.

[11] A method for producing cleaning water for electronic devices, comprising: a pH adjustment step of adding a pH adjuster to ultrapure water to prepare pH-adjusted water; a degassing step of degassing the pH-adjusted water; and a gas dissolution step of dissolving a functional gas in the degassed pH-adjusted water through a gas-permeable membrane to prepare cleaning water, wherein the ultrapure water is transported at a flow rate of 18 L / min or less.

[12] The method for producing cleaning water for electronic devices according to

[11] , further comprising a step of adjusting the pressure of the pH-adjusted water to 0.1 MPa or more.

[13] The method for producing cleaning water for electronic devices according to

[11] or

[12] , wherein the flow rate of the ultrapure water during a standby time when the cleaning water is not being transported to its point of use is controlled to be lower than the flow rate of the ultrapure water required during an operating time when the cleaning water is being transported to the point of use.

[14] The method for producing cleaning water for electronic devices according to

[13] above, wherein the flow rate of the ultrapure water during the standby time is controlled to be 0.1 to 17 L / min.

[15] The method for producing cleaning water for electronic devices according to

[13] above or

[14] above, wherein a value obtained by subtracting the flow rate of the ultrapure water during the standby time from the flow rate of the ultrapure water required during the operating time is more than 0 L / min and not more than 17 L / min.

[16] The method for producing cleaning water for electronic devices according to any one of

[13] to

[15] above, wherein an absolute value of a rate of change in pH of the cleaning water produced during the operating time, based on the pH of the cleaning water produced during the standby time, is 10% or less, and an absolute value of a rate of change in concentration of the functional gas in the cleaning water produced during the operating time, based on the concentration of the functional gas in the cleaning water produced during the standby time, is 10% or less.

[0093] The cleaning water producing device of the present disclosure will be described based on examples. The cleaning water producing device of the present disclosure is not limited to the following examples.

[0094] Example 1 Cleaning water was obtained by dissolving ammonia and hydrogen gas in ultrapure water as described below using a manufacturing apparatus for semiconductor device cleaning water similar to that shown in Figure 1. In the manufacturing apparatus, pipes constituting the transfer line and supply line were made of polyvinylidene fluoride (PVDF) and had an outer diameter of approximately 25 mm and an inner diameter of approximately 20 mm.

[0095] Assuming that cleaning water was produced using the above manufacturing equipment and supplied to semiconductor device manufacturing process equipment, the stability of the concentration of the active ingredient of the pH adjuster in the cleaning water and the stability of the concentration of the functional gas in the cleaning water were evaluated when the flow rate of the resulting cleaning water was changed. In this evaluation, an aqueous ammonia solution (containing ammonia as an active ingredient) was used as the pH adjuster, and hydrogen gas was used as the functional gas. The ammonia in the cleaning water was evaluated by converting the measured value into pH using a conductivity meter, and the hydrogen gas was evaluated using a DH meter.

[0096] ◎: The rate of change in pH or hydrogen gas concentration after the flow rate change is within ±5%. ○: The rate of change in pH or hydrogen gas concentration after the flow rate change is greater than ±5% and within ±10%. ×: The rate of change in pH or hydrogen gas concentration after the flow rate change is greater than ±10%. The rate of change in pH is calculated using the formula (pH after flow rate change - pH before flow rate change) x 100 / (pH before flow rate change). The rate of change in hydrogen gas concentration is also calculated using the same formula.

[0097] The concentration of ammonia in the cleaning water obtained using the cleaning water production apparatus was set to 30 mg / L (pH: 10), and the concentration of hydrogen gas (H2) was set to 1.4 mg / L.

[0098] An aqueous ammonia solution (ammonia concentration: 28%) was prepared by dissolving ammonia in ultrapure water. The above aqueous ammonia solution was added to the ultrapure water flowing through a transfer line to obtain pH-adjusted water. The pH-adjusted water was pressurized to 0.2 MPa using a pump. The pH-adjusted water was supplied to a degassing device (water degassing / aeration module, model number: EF-020-A30, material: poly-4-methylpentene-1, manufactured by DIC). Hydrogen gas and degassed pH-adjusted water were supplied to a gas-dissolved film device (the above water degassing / aeration module), and the hydrogen gas was dissolved in the pH-adjusted water to produce cleaning water.

[0099] Assuming the idling operation of the manufacturing equipment, ultrapure water was transferred at a flow rate of 1 L / min, and then the flow rate of ultrapure water was changed to 2 L / min as the supply to the semiconductor device manufacturing process equipment was assumed. Hereinafter, the flow rate of ultrapure water when the manufacturing equipment was idling will be referred to as the "flow rate during idling operation," and the operation time (standby time) will be referred to as the "idling operation time." Furthermore, the flow rate of ultrapure water when the equipment was being supplied to the manufacturing process equipment will be referred to as the "required flow rate of the manufacturing process equipment," and the operation time (main operation time) will be referred to as the "required time of the manufacturing process equipment." The idling operation time and the required time of the manufacturing process equipment were each set to 10 minutes.

[0100] The pressure of the water flowing through the transfer line was measured to be 0.2 MPa.

[0101] The evaluation results of the cleaning water are as follows: During idling: pH = 10, hydrogen gas concentration (DH) = 1.4 mg / L When required by manufacturing process equipment: pH = 10, hydrogen gas concentration (DH) = 1.4 mg / L Rate of change in pH or hydrogen gas concentration: Within ±5% (◎) Amount of cleaning water saved: 10 L

[0102] [Examples 2 to 4 and Comparative Example 1] Cleaning water was produced in the same manner as in Example 1, except that the conditions were changed as shown in Table 1. The evaluation results are shown in Table 1. In Comparative Example 1, a manufacturing apparatus not equipped with the above-mentioned control device was used, and the flow rate of the ultrapure water was not changed, with the flow rate during idling operation being set to the same flow rate as the required flow rate of the manufacturing process apparatus.

[0103]

[0104] DESCRIPTION OF SYMBOLS 1...Apparatus for producing cleaning water for electronic devices, 11...Hydrogen peroxide removal apparatus, 12...pH adjustment apparatus, 12A...Tank containing pH adjuster, 12B...Pump, 12L...Supply line for pH adjuster, 13...ORP adjustment apparatus, 13A...Tank containing ORP adjuster, 13B...Pump, 13L...Supply line for ORP adjuster, 14...Degassing apparatus, 16...Gas dissolved film type apparatus, 16A...Functional gas supply apparatus, 16L...Functional gas supply line, 18...Water quality or flow rate monitoring apparatus, 20...Flow path switching apparatus, 22...Control apparatus, W...Ultrapure water, W1...pH adjusted water, W2...Cleaning water, L1...Transfer line for ultrapure water, pH adjusted water or cleaning water, L2...Transfer line, L3...Drain line, P1...Pump, UP...Point of use

Claims

1. An apparatus for producing cleaning water for electronic devices, comprising: a pH adjusting device that adds a pH adjuster to ultrapure water to prepare pH-adjusted water; a degassing device that degasses the pH-adjusted water; a gas-dissolving membrane type apparatus that dissolves a functional gas in the degassed pH-adjusted water via a gas-permeable membrane to prepare cleaning water; and a control device that can control the transfer of the ultrapure water at a flow rate of 18 L / min or less.

2. The apparatus for producing cleaning water for electronic devices according to claim 1, further comprising a pump for adjusting the pressure of the pH-adjusted water to 0.1 MPa or more.

3. The apparatus for manufacturing cleaning water for electronic devices as described in claim 1, wherein the control device controls the flow rate of the ultrapure water during standby time when the cleaning water is not being transported to its use point so that it is smaller than the flow rate of the ultrapure water required during operating time when the cleaning water is being transported to the use point.

4. The apparatus for producing cleaning water for electronic devices according to claim 3, wherein the control device controls the flow rate of the ultrapure water during the waiting time to 0.1 to 17 L / min.

5. An apparatus for producing cleaning water for electronic devices as described in claim 3, wherein the value obtained by subtracting the flow rate of the ultrapure water during the standby time from the flow rate of the ultrapure water required during the operating time is greater than 0 L / min and less than 17 L / min.

6. The apparatus for producing cleaning water for electronic devices according to claim 3, wherein the absolute value of the rate of change of the pH of the cleaning water produced during the operating time based on the pH of the cleaning water produced during the waiting time is 10% or less, and the absolute value of the rate of change of the concentration of the functional gas in the cleaning water produced during the operating time based on the concentration of the functional gas in the cleaning water produced during the waiting time is 10% or less.

7. The manufacturing apparatus for cleaning water for electronic devices according to any one of claims 3 to 6, further comprising a switching device for switching the flow path of the cleaning water, wherein the transfer line through which the cleaning water flows is branched at the switching device into a transfer line connected to a use point of the cleaning water and a drain line for draining the cleaning water, and wherein the control device controls the switching device to transfer the cleaning water to the drain line during the standby time, and controls the switching device to transfer the cleaning water to the use point during the operating time.

8. The apparatus for producing cleaning water for electronic devices according to claim 1, wherein the pH adjuster prepares pH-adjusted water having a pH of 8 to 11.

9. The apparatus for producing cleaning water for electronic devices according to claim 1, wherein the pH adjuster adds an aqueous solution of at least one alkaline compound selected from the group consisting of ammonia, tetramethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, sodium hydroxide, and potassium hydroxide to the ultrapure water as the pH adjuster.

10. The apparatus for producing cleaning water for electronic devices according to claim 1, wherein the functional gas is at least one selected from the group consisting of hydrogen gas, ozone gas, carbon dioxide gas, and rare gases.

11. A method for producing cleaning water for electronic devices, comprising: a pH adjustment step of adding a pH adjuster to ultrapure water to prepare pH-adjusted water; a degassing step of degassing the pH-adjusted water; and a gas dissolution step of dissolving a functional gas in the degassed pH-adjusted water via a gas-permeable membrane to prepare cleaning water, wherein the ultrapure water is transported at a flow rate of 18 L / min or less.

12. The method for producing cleaning water for electronic devices according to claim 11, further comprising a step of adjusting the pressure of the pH-adjusted water to 0.1 MPa or more.

13. A method for producing cleaning water for electronic devices as described in claim 11, wherein the flow rate of the ultrapure water during standby time when the cleaning water is not being transported to its use point is controlled to be smaller than the flow rate of the ultrapure water required during operating time when the cleaning water is being transported to the use point.

14. The method for producing cleaning water for electronic devices according to claim 13, wherein the flow rate of the ultrapure water during the waiting time is controlled to 0.1 to 17 L / min.

15. A method for producing cleaning water for electronic devices as described in claim 13, wherein the flow rate of the ultrapure water required during the operating time minus the flow rate of the ultrapure water during the standby time is greater than 0 L / min and not more than 17 L / min.

16. A method for producing cleaning water for electronic devices as described in claim 13, wherein the absolute value of the rate of change in pH of the cleaning water produced during the operating time is 10% or less, based on the pH of the cleaning water produced during the waiting time, and the absolute value of the rate of change in concentration of the functional gas in the cleaning water produced during the operating time is 10% or less, based on the concentration of the functional gas in the cleaning water produced during the waiting time.

Images