JP4800918B2 - Chemical liquid preparation device - Google Patents

Description

  The present invention relates to a chemical liquid preparation apparatus. More particularly, the present invention relates to a chemical preparation apparatus that can accurately prepare a diluted chemical fluid with a super-dilution concentration with less contamination when the chemical fluid is diluted with a dilution fluid at a high dilution ratio (to an ultra-dilute concentration).

  Conventionally, for example, functional water whose function is improved by adding a small amount of ammonia or sulfuric acid to pure water or the like is used as a cleaning liquid used in manufacturing processes of semiconductors, liquid crystal glass, photomasks, and the like. As a method of producing a preparation liquid containing a small amount of ammonia or the like by adding a small amount of ammonia water or a sulfuric acid solution to pure water or the like, that is, a method for producing functional water, pure water or a low concentration ammonia water or the like is usually prepared It is conceivable to add a small amount of aqueous ammonia or the like to the solution to prepare functional water.

  However, for example, when the dilution ratio of pure water or the like with respect to ammonia water or the like is increased to 1000 times or more and an attempt is made to obtain a preparation liquid in which a small amount of ammonia is injected, it is particularly continuous and the total liquid amount is small. In some cases, there is a problem that it is extremely difficult to obtain a preparation solution having an accurate concentration.

  Even if a conventional control valve or metering pump is used, if the overall flow rate is small at a high dilution ratio, a small-diameter pipe must be used as the device. Control valves, metering injection pumps and the like cannot be connected, and the control valves and metering injection pumps that can be connected are special and have to be expensive.

  In view of such a situation, the first solution and the second solution in which the concentration of the component of interest is higher than the first solution using the diffusion injection method are brought into contact with each other through the porous medium, and the second solution is obtained by diffusion. A two-component mixing method characterized by injecting the above solution into the first solution has been proposed (Patent Document 1).

  A substrate made of a porous material in which a plurality of through holes are formed; and a ceramic film formed on the inner surface (inner wall) of the through hole of the substrate. There has been proposed a chemical liquid blending device that controls a chemical fluid injected into a diluted fluid by a porous medium set so that the chemical fluid can be permeated at an injection ratio (Patent Document 2).

JP 2002-143660 A JP 2004-298740 A

  In the method of Patent Document 1, since the injection control from the second solution to the first solution is performed by diffusion through the porous medium, even if the mixing ratio is large and the entire flow rate is small, the continuous method is used. There is an advantage that a mixed solution can be obtained. However, even the above method still leaves room for improvement. That is, in the porous medium (ceramic membrane filter) used in this diffusion injection method, the permeation amount of the drug (for example, ammonia water) is too large. Thus, it is extremely difficult to accurately control the pH of the obtained functional water to 9 to 10 and pure water or the like passes through the outer surface of the porous medium (ceramic membrane filter), so that it is used for semiconductors. Therefore, there has been a problem in that fine particles are mixed into the obtained functional water from the outer surface of the porous medium (ceramic membrane filter) unless sufficient washing with ultrapure water is performed.

  In addition, when adjusting the mixing ratio, it is necessary to prepare a porous medium that can have a desired mixing ratio in advance, and it takes time and effort to replace the porous medium. . Furthermore, since the porous medium which is a ceramic membrane filter contains a small amount of alumina, when it is used for semiconductor cleaning, the semiconductor to be cleaned is not cleaned unless it is sufficiently cleaned with ultrapure water before use. There was a risk of contamination by alumina.

  The chemical liquid preparation device of Patent Document 2 has an advantage that a chemical liquid can be obtained continuously even when the mixing ratio is large and the entire flow rate is small. However, it has been necessary to replace with a porous medium having a predetermined membrane area in accordance with the pH of the chemical fluid, dilution fluid, adjusted chemical, and the like. Therefore, there has been a problem that porous media having various film areas must be prepared in advance. Further, there is a problem that it takes time to replace the porous medium.

  The present invention has been made in view of such problems of the prior art, and the problem is that when diluting a chemical fluid with a dilution fluid at a high dilution ratio (to an extremely diluted concentration), Provided is a chemical compounding device capable of accurately preparing a diluted chemical fluid having a very low concentration with little contamination and easily adjusting the pH (no need to change the porous medium).

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have found that a planar porous flat membrane and an O-ring disposed in a pressed state on one surface of the porous flat membrane. The liquid fluid that has permeated from one side of the porous flat membrane corresponding to the inside of the O-ring is injected into the dilution fluid on the other side. It has been found that the above-mentioned problems can be achieved by providing an injection means having an injection film surface formed thereon, and the present invention has been completed.

  That is, according to the present invention, the following chemical liquid preparation device is provided.

[1] A chemical fluid inflow means, a dilution fluid inflow means, and a chemical fluid which is disposed downstream of the chemical fluid inflow means and flows out from the chemical fluid inflow means is injected into the diluted fluid which has flowed out of the dilution fluid inflow means. A chemical liquid inflow device for handling a flow rate variation of the dilution fluid, comprising: a pH meter, a specific resistance meter, a conductivity meter, and a solenoid valve. Adjustment means, a flow path into which the dilution fluid flows, a storage space for storing the injection means, and a housing provided with a communication hole for communicating the flow path and the storage space, the injection means, a planar porous flat membrane, wherein a porous flat one O- ring disposed in a pressed state by the lid member on the surface of the membrane, the cover member is removable, the cover member O-phosphorus by removing There is configured interchangeably, the porous flat membrane, the portion corresponding to the inside of the O- ring, the chemical fluid which the O- ring has been transmitted from one side disposed is, other An injection membrane surface to be injected into the dilution fluid is formed on the surface side of the injection fluid, and the membrane area of the injection membrane surface is injected into the dilution fluid so that the permeated chemical fluid has a predetermined injection ratio. A chemical compounding device controlled by adjusting the inner diameter of the O-ring to an area that can be controlled.

[2] The chemical preparation apparatus according to [1], wherein the porous flat membrane is configured by a polytetrafluoroethylene resin, a polyvinylidene fluoride resin, a polypropylene resin, a polyethylene resin, a polysulfone resin, or a polyacrylonitrile resin.

[3] The chemical preparation apparatus according to [1] or [2], wherein a porous plate is disposed on the other surface side of the porous flat membrane.

[4] The dilution fluid into which the chemical fluid that has flowed out of the injection unit is injected flows, and the flow of the dilution fluid in which the chemical fluid is injected is disposed inside the flow portion. The chemical preparation apparatus according to any one of [1] to [3], wherein a dissolution unit including a baffle plate that inhibits and generates turbulent flow is disposed.

[5] The chemical solution blending apparatus according to [4], wherein the dissolving means includes a plurality of the baffle plates, and a piece-shaped molded body is filled between the adjacent baffle plates.

[6] The chemical liquid preparation device according to any one of [1] to [5], wherein the chemical fluid is ammonia water or ammonia gas.

  The chemical compounding device of the present invention can accurately prepare a diluted chemical fluid with a very low concentration of contamination when diluting the chemical fluid with a dilution fluid at a high dilution ratio (to an extremely diluted concentration). The pH can be easily adjusted (the exchange of the porous medium is not necessary).

  BEST MODE FOR CARRYING OUT THE INVENTION The best mode for carrying out the present invention will be described below, but the present invention is not limited to the following embodiment, and is based on the ordinary knowledge of those skilled in the art without departing from the gist of the present invention. It should be understood that modifications and improvements as appropriate to the following embodiments also fall within the scope of the present invention.

[1] Chemical liquid preparation device:
It is explanatory drawing which shows typically one Embodiment of the chemical | medical solution preparation apparatus of this invention. As shown in FIG. 3, the chemical compounding apparatus 100 of this embodiment is disposed downstream of the chemical fluid inflow means 10, the dilution fluid inflow means 20, and the chemical fluid inflow means 10, and flows out from the chemical fluid inflow means 10. Injection means 30 for injecting the chemical fluid into the diluted fluid flowing out from the dilution fluid inflow means 10, and the injection means 30 has a flat porous flat membrane 31 and one surface of the porous flat membrane 31. O-ring disposed in a pressed state, and transmitted from one side of the porous flat membrane 31 corresponding to the inner side of the O-ring from one surface side where the O-ring is disposed. An injection membrane surface in which the chemical fluid is injected into the dilution fluid on the other side is formed, and the membrane area of the injection membrane surface is changed to the diluted fluid so that the permeated chemical fluid has a predetermined injection ratio. Adjust the inner diameter of the O-ring to the area that can be injected. In which was controlled by.

  With this configuration, when diluting a chemical fluid with a dilution fluid at a high dilution ratio (to an ultra-dilute concentration), it is possible to accurately prepare a diluted drug-fluid with a very low concentration with less contamination, and pH Is easy to adjust.

[1-1] Chemical fluid inflow means:
The chemical fluid inflow means is not particularly limited as long as it has a configuration that allows the chemical fluid to flow into the injection means. For example, the chemical compounding apparatus 100 shown in FIG. 3 includes a canister 61 that stores chemical fluid, and a pressurized nitrogen gas cylinder 12 that is connected to the canister 11 and pressurizes pressurized nitrogen gas into the canister 11. This is an example in which a chemical fluid inflow means 10 is provided in which a filter 13 for removing fine particles is provided in a pressurized nitrogen gas injection pipe. The chemical fluid is not particularly limited, but is preferably ammonia water or ammonia gas, for example.

  Among these chemical fluids, ammonia water is preferably used for the following reasons. That is, conventionally, chemicals used for cleaning semiconductors, liquid crystal glass, photomasks, and the like have been used in which carbon dioxide gas is dissolved in ultrapure water to prevent charging. However, in use at a low specific resistance value, there are problems such as it takes time to dissolve the carbon dioxide gas and bubbles are easily generated. In addition, since fine particles adhering to a semiconductor or the like are generally negatively charged at the time of cleaning, when the chemical liquid is acidic, the chemical liquid is positively charged. Accordingly, the surface of the cleaning object such as a semiconductor is positively charged. Therefore, the fine particles adhering to the semiconductor and the like and the object to be cleaned such as the semiconductor attract each other, and performing antistatic on the acidic side (the chemical is acidic) is to wash the object to be cleaned. It is not preferable from the viewpoint. Therefore, it is preferable to use ammonia water as the chemical fluid from the viewpoint of preventing charging and making the chemical liquid alkaline.

[1-2] Dilute fluid inflow means:
The dilution fluid inflow means is not particularly limited as long as it has a configuration capable of allowing dilution fluid to flow in. For example, the chemical compounding apparatus 100 shown in FIG. 3 has a storage tank 21 for storing the diluted fluid, a pump (not shown) for discharging the diluted fluid from the storage tank 21, and a pressure reducing valve 22 is further provided. It is an example provided with the dilution fluid inflow means 20. When using pressurized ultrapure water (diluted fluid) at a predetermined flow rate, the pump need not be used. The dilution fluid is not particularly limited, but is preferably ultrapure water, for example.

[1-3] Injection means:
The injection means is arranged downstream of the chemical fluid inflow means and is for injecting the chemical fluid flowing out from the chemical fluid inflow means into the diluted fluid flowing out from the dilution fluid inflow means. A membrane and an O-ring disposed in a pressed state on one surface of the porous flat membrane. And the chemical fluid which permeate | transmitted from the one surface side by which the O-ring was arrange | positioned in the part corresponding to the inner side of the O-ring of the said porous flat membrane is inject | poured into dilution fluid on the other surface side. An injection film surface is formed. This injection means adjusts the inner diameter of the O-ring so that the membrane area of the injection membrane surface can be injected into the diluted fluid so that the permeated chemical fluid has a predetermined injection ratio. It is controlled.

  For example, as shown in FIG. 1, the chemical liquid blending apparatus of the present embodiment is disposed downstream of the chemical fluid inflow means 10 shown in FIG. 3, and is a cylindrical channel 41 into which ultrapure water (diluted fluid) flows. The injection means 30 is disposed in the storage space 42 of the polypropylene housing 40 having a cylindrical storage space 42 for storing the injection means 30 and a columnar communication hole 43 for communicating the flow path 41 and the storage space 42. It is stored. The material of the housing is not limited to polypropylene resin, and polytetrafluoroethylene resin, tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin, polyvinylidene fluoride (PVDF) resin, or the like can be used.

  In addition, the shape of the communication hole 43 of the housing 40 is not particularly limited. However, in the case of a cylindrical shape, the diameter is preferably 0.1 to 2.0 mm, and preferably 0.5 to 1.0 mm. Further preferred. If the thickness is less than 0.1 mm, the resistance increases and ammonia water cannot be injected. On the other hand, if it exceeds 2.0 mm, ammonia water may be excessively injected.

  The chemical preparation apparatus of the present invention is an apparatus that solves the problems of the method of Patent Document 1 and the chemical preparation apparatus of Patent Document 2, for example. That is, the chemical fluid can be permeated at a predetermined injection rate by adjusting the inner diameter of the O-ring as described above. Therefore, it is only necessary to prepare a large number of O-rings with different inner diameters, and it is easy to change the pH only by replacing the O-ring according to the pH of the chemical fluid, dilution fluid, adjusted chemical, etc. There is an advantage that it can be adjusted.

[1-3-1] Porous flat membrane:
The porous flat film is a thin film having a large number of fine pores that are continuous in a three-dimensional shape. The pore diameter of the pores of the porous flat membrane is not particularly limited, but is preferably 0.05 to 0.5 μm, more preferably 0.08 to 0.2 μm, and 0.1 μm. Is particularly preferred. If the pore diameter is less than 0.05 μm, ammonia water may not be injected. On the other hand, if the pore diameter is more than 0.5 μm, fine particles in the ammonia water may flow out. In addition, it is preferable that the pore diameter of the porous plate is uniform. This has the advantage that homogeneous ammonia water can be injected.

  The porous flat membrane may be composed of any material, but when a fluid that is antistatic and alkaline is used as the chemical fluid, particularly when aqueous ammonia is used, Preferably, it is composed of a hydrophilic material, such as polytetrafluoroethylene (PTFE) resin, tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA) resin, polyvinylidene fluoride (PVDF) resin. , Polypropylene (PP) resin, polyethylene (PE) resin, polysulfone (PS) resin, or polyacrylonitrile (PAN) resin is preferable. Among these, a porous flat membrane made of PTFE resin is preferable.

  The shape of the porous flat membrane is not particularly limited as long as it is a shape that exhibits the effects of the present invention, and may be, for example, a circular shape, a rectangular shape, or a square shape. For example, in the case of a circular porous flat membrane, the diameter is preferably 1 to 7 mm, more preferably 2 to 6 mm, and particularly preferably 3 to 5 mm. If the hole diameter is less than 1 mm, the processing may be difficult. On the other hand, if the pore diameter is more than 7 mm, it is difficult to adjust the amount of ammonia water to be injected, so that ammonia water may be excessively injected.

  Examples of such commercially available porous flat membranes include poreflon (manufactured by Sumitomo Electric Fine Polymer Co., Ltd.), hydrophilic PTFE type membrane filter (manufactured by Advantech Toyo Co., Ltd.), and the like.

  The above-mentioned porous flat membrane can be hydrophobic, but when using a hydrophobic porous flat membrane, it is necessary to hydrophilize the porous flat membrane with alcohol before use. Therefore, the work becomes complicated. In addition, the alcohol used for the hydrophilization may be mixed in a dilution fluid (for example, ultrapure water). From these viewpoints, the porous flat membrane is preferably hydrophilic.

[1-3-2] O-ring:
The O-ring is disposed in a pressed state on one surface of the porous flat membrane. As the material of the O-ring, a known material can be used, and it is preferable that the material has resistance to the chemical fluid. For example, an O-ring made of ethylene propylene diene rubber (EPDM), perfluoro rubber, silicon rubber, fluoro rubber, Viton or the like can be used.

  For example, as shown in FIG. 1, the chemical liquid preparation device of the present embodiment is arranged on a columnar lid member 50 having a cylindrical lid portion through-hole 50 a into which a chemical fluid flows, and on the outer periphery of the lid member 50. The pressed O-ring 51 presses the O-ring 32 disposed between the lid member 50 and the circular porous flat membrane 31 onto one surface of the porous flat membrane 31. Is.

  In addition, the shape of the lid part through-hole 50a of the lid member 50 is not particularly limited, but in the case of a columnar shape, the diameter is preferably 0.1 to 2 mm, and more preferably 0.5 to 1 mm. preferable. If the thickness is less than 0.1 mm, the resistance increases and ammonia water cannot be injected. On the other hand, if it exceeds 2 mm, it is difficult to adjust the amount of ammonia water to be injected, so that ammonia water may be excessively injected.

  The injection means of the chemical compounding device of the present invention is such that the chemical fluid permeated from one side of the porous flat membrane corresponding to the inner side of the O-ring is disposed on the other side. An injection film surface to be injected into the dilution fluid is formed on the surface side. The surface of the injection membrane is controlled so that the membrane area can be injected into the diluted fluid so that the permeated chemical fluid has a predetermined injection ratio. The control of the membrane area can be easily performed by adjusting the inner diameter of the O-ring. Here, the “portion corresponding to the inside of the O-ring” refers to a porous flat membrane that is annularly partitioned by the O-ring when the O-ring is pressed onto one surface of the porous flat membrane. Means an area.

The area of the injection membrane surface is not particularly limited as long as it is an area that can be injected into the diluted fluid so that the permeated chemical fluid has a predetermined injection ratio, but is 0.05 to 0.4 cm ² . preferably there, more preferably 0.08～0.3Cm ^2, and particularly preferably 0.1~0.2cm ^2. If it is less than 0.05 cm ² , it may be necessary to apply a high pressure to inject ammonia water. On the other hand, if it exceeds 0.4 cm ² , the pressure for injecting the ammonia water becomes low, and it becomes impossible to obtain a sufficient differential pressure with respect to the water pressure. May not be able to be injected.

  That is, the diameter of the O-ring is preferably 2.5 to 7 mm, more preferably 3 to 6 mm, and particularly preferably 3.5 to 4 mm. If it is less than 2.5 mm, it may be necessary to apply high pressure in order to inject ammonia water. On the other hand, if it exceeds 7 mm, the pressure for injecting the ammonia water becomes low and the differential pressure from the water pressure cannot be taken sufficiently. Therefore, when the water pressure fluctuates, the water pressure becomes higher and the ammonia water can be injected. There is a risk of disappearing.

[1-3-3] Porous plate:
The porous plate is for supporting the porous flat membrane, and has a large number of fine pores that are three-dimensionally continuous. By disposing such a porous plate on the other surface (the surface opposite to the one surface on which the O-ring is disposed) of the porous flat membrane, the chemical liquid flowing out from the chemical fluid inflow means There is an advantage that the porous flat membrane can be prevented from being deformed or damaged by the inflow pressure of the fluid.

  For example, as shown in FIG. 1, the chemical compounding device of the present embodiment has a cylindrical shape on the other surface (the surface opposite to the one surface on which the O-ring 32 is disposed) of the porous flat membrane 31. The porous plate 60 is provided.

  The porous plate is not particularly limited as long as it satisfies the above conditions, but the pore diameter is preferably 1 to 10 μm, more preferably 2 to 8 μm, and 5 μm. Is particularly preferred.

  The kind of the porous plate is not particularly limited, and ceramics, polytetrafluoroethylene (PTFE) resin, and the like can be used. Among these, polytetrafluoroethylene (PTFE) resin is preferable. The kind of the ceramic is not particularly limited, and examples thereof include at least one selected from the group consisting of alumina, silica, silica-alumina, mullite, cordierite, and zirconia.

  The thickness of the porous plate is preferably 1 to 10 mm, more preferably 2 to 8 mm, and particularly preferably 5 mm. If it is less than 1 mm, it may be damaged during assembly. On the other hand, if it exceeds 10 mm, the resistance increases, and there is a risk of restricting the flow of the chemical fluid.

  Further, the shape of the porous plate is not particularly limited as long as it can support the porous flat membrane, and can be, for example, a cylindrical shape, a cubic shape, a rectangular parallelepiped shape, or the like.

  Here, the chemical solution used for cleaning semiconductors, liquid crystal glass, photomasks, and the like is generally negatively charged with fine particles adhering to the semiconductor or the like, so that the pH is within the range of 9 to 10, The potential is required to be negative in order not to couple by repulsive force. Therefore, it is necessary to adjust the chemical solution to be prepared in the chemical preparation device of the present invention to a pH within the above range, and the chemical preparation device of the present invention controls the area of the above-described injection film surface, that is, O−. By adjusting the inner diameter of the ring, the pH can be adjusted.

Specifically, the differential pressure between ammonia water (chemical fluid) and ultrapure water (diluted fluid) is 0.1 MPa (chemical fluid (MPa)> diluted fluid (MPa)), the fluid temperature is 23 ° C., When the pore diameter of the membrane pores is 0.1 μm, the thickness of the porous plate is 5 mm, and the pore diameter is 5 μm, the permeation amount of the 5 wt% ammonia water injection means is 20 mL. / Min / cm ² . In this case, ammonia water needs to be added at a concentration of about 7 mg / L in order to adjust the pH of the ultrapure water to 10. Therefore, in order to add ammonia water at the above concentration, the membrane area may be 0.14 cm ² . That is, the pH of ultrapure water can be set to 10 by using an O-ring having a diameter (inner diameter) of 4 mm.

[1-4] Dissolution means:
The chemical preparation apparatus of the present invention is provided with a flow portion in which the diluted fluid injected with the chemical fluid flowing out from the injection means flows and the flow portion, and the flow of the diluted fluid into which the chemical fluid is injected is inhibited. Thus, it is preferable to dispose a dissolving means including a baffle plate that generates a turbulent flow. Such a dissolving means has an advantage that the chemical fluid and the dilution fluid can be reliably mixed.

  As shown in FIG. 1, for example, a plurality of dilution fluids into which a chemical fluid that has flowed out of the injection unit 30 is injected are provided in the chemical unit of the present embodiment. And a baffle plate 72 that is arranged in a staggered manner so as to partially overlap each other, and has a baffle plate 72 that inhibits the flow of the diluted fluid into which the chemical fluid is injected and generates turbulent flow. Is. The flow part is not particularly limited as long as the diluted fluid into which the chemical fluid that has flowed out of the injection means is flowed, and, for example, a housing 40 like the dissolution means 70 shown in FIG. Of these channels 41, the space downstream from the communication hole 43 can be used as the flow portion 71, or a pipe or the like can be added to the flow channel 41 of the housing 40, and this tube can be used as the flow portion. In addition, the baffle plate is arranged in the flow part and is particularly limited in size, shape, arrangement, etc., as long as it inhibits the flow of the diluted fluid injected with the chemical fluid and generates turbulence. There is no limit.

  Furthermore, examples of the dissolving means include a line mixer. These can be used alone or in combination. For example, the chemical compounding device 100 illustrated in FIG. 3 is an example in which a line mixer 73 is provided downstream of the fluidizing unit 71 and the baffle plate 72 illustrated in FIG. 1.

  In addition, when the said melt | dissolution means is provided with the several baffle plate, it is also preferable to fill a small-piece-shaped molded object between adjacent baffle plates. Examples of the small-shaped molded body include pipe pieces and small spheres. Thus, by filling the small piece-shaped molded body, there is an advantage that the chemical fluid and the dilution fluid can be mixed more reliably.

[1-5] Other means:
In addition to the above-described chemical fluid inflow means, dilution fluid inflow means, injection means, and dissolution means, the chemical liquid preparation device of the present invention can include chemical fluid inflow adjustment means, ultrasonic wave generation means, and the like.

Examples of the chemical fluid inflow adjusting means include one provided with any one of a pH meter , a resistivity meter , and a conductivity meter , and an electromagnetic valve. For example, the chemical liquid blending apparatus 100 shown in FIG. 3 is an example provided with chemical fluid inflow adjusting means 80 having a high-speed electromagnetic valve (S) 81 and a conductivity meter (XIS) 82 . Since ammonia water (chemical fluid) is added in a very small amount to ultrapure water (diluted fluid), a pH meter and It is preferable to feedback control the addition of ammonia water using a solenoid valve. In this case, since the pH meter has a slow response speed, a correlated conductivity meter or resistivity meter can also be used.

  The ultrasonic wave generating means improves the removal efficiency of the fine particles on the surface of the cleaning object by using ultrasonic waves together when cleaning the surface of the cleaning object such as a semiconductor. As an ultrasonic wave generation means, an ultrasonic oscillator can be mentioned, for example.

  In general, the fine particles are negatively charged and adhere to the object to be cleaned by electrostatic force. When the fine particles are forcibly separated from the object to be cleaned using ultrasonic waves of 50 kHz to 3 MHz, a chemical solution (diluted ammonia water) is used at the same time. As a result, the surface of the object to be cleaned is negatively charged, and it is possible to prevent the fine particles once separated due to the electric repulsive force from reattaching to the object to be cleaned. At this time, as a chemical fluid having alkalinity, for example, a chemical solution containing metal ions such as sodium hydroxide (NaOH) and potassium hydroxide (KOH) is used instead of a chemical solution to prevent metal contamination by the chemical solution. You can also. If the pH is too high (the ammonia concentration is too high), depending on the object to be cleaned, the surface is etched, so the pH is preferably 10 or less.

  The flow of each fluid in the chemical preparation apparatus of the present invention will be described below based on FIGS. 1 and 3.

  First, ultrapure water (diluted fluid) is allowed to flow into the housing 40 from the diluted fluid inflow means 20. Thereafter, ammonia water (chemical fluid) is caused to flow from the chemical fluid inflow means 10 into the injection means 30 accommodated in the housing 40. The ammonia water that has flowed into the injection means 30 is restricted in flow by the porous flat membrane 31, and a desired amount of ammonia water permeates the porous flat membrane 31. When the porous flat membrane 31 is provided in this way, pulsation hardly occurs in the flow rate of the ammonia water. Therefore, when the ammonia water is diluted with ultrapure water at a high dilution ratio (to an ultradilution concentration), it becomes possible to accurately prepare a chemical solution with ultradilution concentration (ultrapure water into which ammonia water has been injected). The amount of ammonia water that passes through the porous flat membrane 31 can be controlled by the inner diameter of the O-ring 32. That is, if the inner diameter of the O-ring 32 is large, a large amount of ammonia water permeates, and if the inner diameter of the O-ring 32 is small, a small amount of ammonia water permeates.

  The ammonia water that has permeated the porous flat membrane 31 in this way further permeates the porous plate 60. The ammonia water that has passed through the porous plate 60 passes through the communication hole 43 of the housing 40 and is injected into the ultrapure water at a predetermined rate. The ammonia water can be prevented from flowing into the communication hole 43 by applying a pressure higher than that of the ultra pure water. Thereafter, ultrapure water into which ammonia water has been injected is thoroughly mixed by a dissolving means. Thus, a chemical | medical solution is prepared and the washing | cleaning target objects, such as a semiconductor, can be wash | cleaned by sending this chemical | medical solution to a washing machine.

The pH of the chemical solution can be adjusted by removing the lid member 50 and replacing the O-ring 32. After replacing the O-ring 32, the lid member 50 may be attached.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples.

Example 1
First, a polypropylene housing having a housing space was prepared, and a PTFE porous plate having a thickness of 5 mm, a diameter of 4 mm, and a pore diameter of 10 μm was housed in the housing. Thereafter, a porous flat membrane made of hydrophobic PTFE having a membrane area of 0.14 m ² , a diameter of 4 mm, and a pore diameter of 0.1 μm was disposed on the porous plate. Subsequently, an EPDM O-ring having a diameter of 4 mm was disposed. Thereafter, the O-ring was pressed on one surface of the porous flat membrane.

  Next, as shown in FIG. 2, the flow rate of ultrapure water used depending on the operation mode of the washing machine is varied in the range of 2 to 20 L / min, and ammonia water having a concentration of 5 wt% is added in-line. Then, the pH was controlled to be 10. In addition, since the water pressure of ultrapure water is set to be 0.15 MPa by the pressure reducing valve, the water pressure does not vary even if the flow rate of ultrapure water varies. The supply pressure of the ammonia water to the porous flat membrane is 0.25 MPa, and the filtration pressure applied to the membrane is 0.1 MPa (= 0.25 to 0.15). The pH is controlled with a specific resistance meter (model number HE-480R, manufactured by HORIBA STEC Co., Ltd.) because the pH meter has low electrode responsiveness so that the specific resistance value is about 0.04 MΩ · cm. . After adding ammonia water to ultrapure water, mixing was performed with a line mixer (model No. MX666-R6, manufactured by Noritake Company) in order to promote single flow, dissolution, and dispersion of ammonia water.

  As a result of the above control, as shown in FIG. 2, the specific resistance value in this example was in the range of 0.04 to 0.1 MΩ · cm. This is equivalent to 9.6 to 10 in terms of pH value, and it was confirmed that the pH can be controlled with high accuracy within a very narrow range. The specific resistance value is 0.04 MΩ · cm when pH = 10, and the specific resistance value is 1.0 MΩ · cm when pH = 9.6.

  Moreover, the glass substrate was wash | cleaned in the washing machine using the obtained ultra-dilute ammonia water. As a result, 50 fine particles remained on the glass substrate after cleaning, and it was confirmed that the cleaning property was high. In this evaluation, “fine particles” means particles having a particle diameter of 0.2 μm or more.

(Comparative Example 1)
A chemical solution was prepared while controlling the pH of the chemical solution in the same manner as in Example 1 except that the injection means was not used. Note that the flow rate of the metering pump was 5 mL / min, and because it was a diaphragm type, pulsation occurred in the flow rate, and the flow rate varied. Therefore, the discharge pressure of the pump was constantly changing, and ammonia water was supplied to ultrapure water in the range of 0.1 to 0.3 MPa. The electrical conductivity at this time was 0.006 to 0.3 MΩ · cm, and the pH varied in the range of 9 to 11. Moreover, the obtained ultra-dilute ammonia water was used to clean the glass substrate in a cleaning machine. As a result, 100 fine particles remained on the glass substrate after washing. In this evaluation, “fine particles” means particles having a particle diameter of 0.2 μm or more.

  As described above, it was confirmed that the chemical liquid preparation device of Example 1 was capable of controlling the pH with high accuracy in a very narrow range as compared with the chemical preparation device of Comparative Example 1. Moreover, it has confirmed that the chemical | medical agent obtained by the chemical | medical solution preparation apparatus of Example 1 had high detergency compared with the chemical | medical agent obtained by the chemical | medical agent preparation apparatus of Comparative Example 1.

  The chemical compounding device of the present invention is capable of accurately preparing a diluted chemical fluid with a very low concentration of contamination when diluting the chemical fluid with a dilution fluid at a high dilution ratio (to an extremely diluted concentration). It is suitably used as a device.

It is explanatory drawing which shows typically one Embodiment of the injection | pouring means of the chemical | medical solution preparation apparatus of this invention. It is a graph which shows the relationship between the specific resistance value of the ultra diluted ammonia water obtained in Example 1 of the chemical | medical solution preparation apparatus of this invention, and the comparative example 1, and the flow volume of ultra pure water. It is explanatory drawing which shows typically one Embodiment of the chemical | medical solution preparation apparatus of this invention.

Explanation of symbols

10: chemical fluid inflow means, 11: canister can, 12: pressurized nitrogen gas cylinder, 20: dilution fluid inflow means, 21: storage tank, 22: pressure reducing valve, 30: injection means, 31: porous flat membrane, 32: O-ring, 40: housing, 41: flow path, 42: storage space, 43: communication hole, 50: lid member , 51: O-ring , 60: porous plate, 70: dissolution means, 71: flow section, 72: baffle plate, 73: line mixer, 80: chemical fluid inflow adjusting means, 81: high-speed solenoid valve, 82: conductivity meter, 100: chemical compounding device.

Claims (6)

Chemical fluid inflow means,
Dilution fluid inflow means;
An infusion means that is disposed downstream of the medicinal fluid fluid inflow means and injects medicinal fluid that has flowed out of the medicinal fluid inflow means into the diluted fluid that has flowed out of the diluting fluid inflow means,
a chemical fluid inflow adjusting means for coping with flow rate fluctuations of the diluted fluid, comprising a pH meter, a resistivity meter, a conductivity meter, and a solenoid valve;
A flow path through which the dilution fluid flows, a storage space for storing the injection means, and a housing having a communication hole for communicating the flow path and the storage space,
The injection means includes a planar porous flat membrane, and an O-ring disposed on one surface of the porous flat membrane while being pressed by a lid member ,
The lid member is removable, and the O-ring is configured to be replaceable by removing the lid member.
The medicinal fluid permeated from one side of the porous flat membrane corresponding to the inside of the O-ring is injected into the dilution fluid on the other side. The injection film surface to be formed is formed,
The membrane area of the injection membrane surface is controlled by adjusting the inner diameter of the O-ring to an area where the permeated chemical fluid can be injected into the dilution fluid so as to have a predetermined injection ratio. Chemical liquid preparation device.   The chemical | medical solution preparation apparatus of Claim 1 with which the said porous flat film was comprised with the polytetrafluoroethylene resin, the polyvinylidene fluoride resin, the polypropylene resin, the polyethylene resin, the polysulfone resin, or the polyacrylonitrile resin.   The chemical | medical solution preparation apparatus of Claim 1 or 2 with which the porous board was arrange | positioned by the said other surface side of the said porous flat membrane. A flow part in which the dilution fluid into which the chemical fluid that has flowed out of the injection means has flowed;
The dissolution means provided with the baffle plate arrange | positioned inside the said flow part and inhibiting the flow of the said dilution fluid in which the said chemical | medical solution fluid was inject | poured and generating a turbulent flow is arrange | positioned. The chemical | medical solution preparation apparatus as described in any one of these. The melting means comprises a plurality of the baffle plates,
The chemical | medical solution preparation apparatus of Claim 4 with which the small-piece shaped molded object was filled between the said adjacent baffle plates.   The chemical liquid preparation device according to any one of claims 1 to 5, wherein the chemical fluid is ammonia water or ammonia gas.

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