JP2010267181A - Device for diluting chemical agent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diluting device capable of preventing mixing of impurities with a compact facility, when adjusting a chemical agent such as developing solution used in a method of manufacturing a semiconductor, liquid crystal or the like to a desired concentration by diluting a heavily doped stock solution thereof with pure water or the like. <P>SOLUTION: The diluting device for chemical agent includes a dilution tank 1 to which the chemical agent and a diluent are introduced. The dilution tank 1 includes a magnetic floating pump 2 for agitating the liquid within the dilution tank 1, and a concentration meter 3 for measuring the concentration of the chemical agent. Based on a desired concentration of the chemical agent, the amount of the chemical agent and the amount of the diluent are controlled so that the measured value gets close to the desired concentration. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an apparatus for diluting a drug.

  In various manufacturing processes, a drug diluted to a desired concentration is used. For example, a developer used in a manufacturing process for semiconductors, liquid crystals, and the like needs to be adjusted to a desired concentration by diluting a high concentration stock solution with ultrapure water or the like before use.

  As an apparatus for adjusting a drug having a desired concentration, Patent Document 1 describes a reagent adjusting apparatus that adjusts a working concentration by diluting a reagent with a high concentration and supplies it to a clinical test apparatus. Patent Documents 2 and 3 describe an automatic developer diluting device that mixes the liquid in the preparation tank using a circulation pump.

Japanese Patent Laid-Open No. 9-33538 (published February 7, 1997) Japanese Patent Laid-Open No. 5-216241 (released on August 27, 1993) JP 6-61136 A (published March 4, 1994)

  By the way, when diluting a drug (for example, a stock solution of a developer used for manufacturing a semiconductor), in order to obtain a desired concentration accurately or to prevent deterioration of the drug, mixing of impurities must be suppressed. Don't be. In particular, a developer or the like used for manufacturing semiconductors, liquid crystals, and the like must suppress contamination of impurities (metal impurities, particles, etc.) as much as possible.

  However, in the apparatus described in Patent Document 1, mixing in the preparation tank is performed by a stirring blade, and a shaft for rotating the stirring blade (stirring shaft) has a structure penetrating the preparation tank. In view of the problem that impurities are mixed into the tank from the penetrating part (shaft seal, etc.), or impurities generated by sliding, abrasion, etc. of the shaft seal material are mixed into the tank and the tank is contaminated. Yes. In addition, the stirring blade, the stirring shaft, etc. are made of a metal such as stainless steel (SUS) in order to ensure its strength, and the surface is often coated with a fluororesin, etc. In addition, there is a risk that the base metal is eluted due to deterioration of the coating agent. Furthermore, the scraps of the stirring blade or its peripheral members that are worn by friction due to the rotation of the stirring blade may become impurities.

  Since the devices described in Patent Documents 2 and 3 discharge the liquid in the tank to the piping outside the tank and then return it to the tank, mixing takes a long time and requires equipment such as a circulation pump and piping outside the tank. As a result, the apparatus becomes complicated and large.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a diluting apparatus that can prevent impurities from being mixed and has a compact facility.

  In order to solve the above problems, a diluting device according to the present invention is a drug diluting device including a container into which a drug and a diluent are introduced, and agitates the liquid in the container in the container. A magnetic levitation pump is provided.

  Moreover, it is more preferable that the dilution apparatus according to the present invention further includes a concentration meter that measures the concentration of the drug in the liquid in the container.

  In the dilution apparatus according to the present invention, a first adjusting means for adjusting the amount of the drug introduced into the container, and a second adjusting means for adjusting the amount of the diluent introduced into the container. , Receiving the measurement value in the densitometer, and based on the measurement value and a desired concentration of the medicine inputted in advance, the first adjustment means and the second adjustment unit so as to bring the measurement value closer to the desired concentration More preferably, it further comprises control means for controlling the adjusting means.

  As described above, the dilution apparatus according to the present invention is a drug dilution apparatus including a container into which a drug and a diluent are introduced, and the magnetic levitation for stirring the liquid in the container in the container. Since the pump is provided, it is possible to prevent the contamination of impurities and to provide a diluting device having a compact equipment.

It is a figure which shows typically the structure of the dilution apparatus in one Embodiment of this invention.

  An embodiment of a diluting device according to the present invention will be described below with reference to FIG. FIG. 1 is a diagram schematically showing a configuration of a dilution apparatus according to an embodiment of the present invention.

The diluting device according to the present invention is a device for diluting a drug with a diluent, and can be applied to any drug. The present invention can be suitably applied particularly to a drug in which impurities are not preferably mixed. Examples of agents to which the present invention can be suitably applied include a stock solution of a developer, hydrogen fluoride (HF), ammonium water (NH ₄ OH), a stock solution of a cleaning solution, and the like. Further, the number of drugs in the present invention may be one, but a plurality of drugs may be used. That is, the diluting apparatus according to the present invention can be suitably applied to the case where a plurality of drugs are mixed and diluted with a diluting solution, and therefore, for example, various mixed acids can be prepared. Examples of the mixed acid include a mixture of HF, H ₂ O ₂ and pure water. An example of preparing a mixed acid according to the present invention is a method of introducing a predetermined amount of HF into the dilution tank 1 and then introducing a predetermined amount of H ₂ O ₂ and then mixing pure water. When HF and H ₂ O ₂ are mixed with pure water, it is preferable to use a near-infrared spectrophotometer as the concentration meter.

  For example, a developer used in a manufacturing process for semiconductors, liquid crystals, and the like must particularly strictly prevent impurities from being mixed. In this regard, the diluting apparatus according to the present invention can prevent impurities from being mixed at the time of dilution, and therefore can be suitably used when diluting the stock solution of the developer in the case described above.

  The diluent used in the present invention is a liquid for diluting the drug to which the present invention is applied, and any liquid can be used as long as it can be used as a solvent for the drug.

  In the present embodiment, a case where a stock solution of a developer is used as a drug and ultrapure water is used as a diluent will be described.

  As shown in FIG. 1, the dilution apparatus according to the present embodiment includes a dilution tank (container) 1.

  The dilution tank 1 is a container for diluting the stock solution of the developer, and is diluted by introducing and mixing the stock solution of the developer and ultrapure water.

  Further, a pipe for discharging the internal liquid is connected to the lower part of the dilution tank 1, and a control valve 10 is provided in this pipe. By opening / closing the control valve 10, the discharge of the liquid in the dilution tank 1 can be started or stopped.

  Further, a magnetic levitation pump 2 for stirring the liquid in the dilution tank 1 is provided at the lower part of the dilution tank 1, and the dilution tank 1 and the magnetic levitation pump 2 are integrated.

  The magnetic levitation pump 2 is a pump that sucks and discharges liquid by rotating a rotating part levitated by magnetic force in a non-contact manner by magnetic force. The magnetic levitation pump 2 has a suction port (not shown) and a plurality of discharge ports (not shown) toward the dilution tank 1. As shown by the arrow in FIG. 1, the magnetic levitation pump 2 sucks the liquid in the dilution tank 1 from the suction port, and then ejects the liquid into the dilution tank 1 from a plurality of discharge ports. The liquid in 1 is mixed. Thereby, the stock solution of the developer and the ultrapure water are mixed. Thus, since the magnetic levitation pump 2 is provided with a plurality of jet outlets for jetting the liquid into the dilution tank 1, the liquid in the dilution tank 1 can be stirred efficiently.

  Here, as the magnetic levitation pump 2, for example, a rotating part such as an impeller that sucks and discharges liquid by rotating, a support part that floats and supports the rotating part by magnetic force, and non-contact by magnetic force It is possible to use a pump or the like provided with a drive unit that rotationally drives the rotating unit. Moreover, as the magnetic levitation pump 2, for example, a PTM series magnetic levitation pump manufactured by LEVITRONIX or the like can be used.

  In addition, the place where the magnetic levitation pump in the present invention is provided is not particularly limited to the lower part of the dilution tank, and may be, for example, an upper part or a side part in the dilution tank as long as the position is immersed in the liquid in the dilution tank. Good.

  By using the magnetic levitation pump 2, the diluting device in the present embodiment does not require a shaft or the like for rotating the rotating part to penetrate the wall or the like of the diluting tank 1. Therefore, when a shaft or the like is passed through the tank wall, impurities or the like that can be mixed in from the penetration portion are prevented, and scraps such as shafts worn by friction due to the rotation of the shaft and surrounding members are mixed as impurities. Therefore, the present invention can be suitably used even when impurities such as impurities must be strictly suppressed. Further, the magnetic levitation pump 2 is provided and integrated in the dilution tank 1 and mixes the liquid only in the dilution tank 1, so that a circulation pump, piping and the like for circulating the liquid are provided outside the dilution tank 1. Since it is not necessary, the equipment becomes compact and the liquid in the dilution tank 1 can be mixed in a short time.

  A concentration meter 3 and a load cell 4 are attached to the dilution tank 1. Moreover, the ultrapure water tank 5 and the undiluted | stock solution tank 6 are connected to the dilution tank 1 via piping.

  The concentration meter 3 is a meter that measures the concentration of the developer in the liquid in the dilution tank 1. As the densitometer 3, for example, a conductivity type, an ultrasonic type, a refractive index type or the like can be used. Since the concentration of the developer in the dilution tank 1 can be confirmed by the densitometer 3, the concentration can be corrected based on this. In the present embodiment, the density correction is performed by the programmable controller 7 described later, but the density correction may be performed manually. By thus correcting the concentration, the drug can be diluted accurately.

  The densitometer 3 is preferably provided directly on the dilution tank 1 by, for example, direct attachment. Thereby, while being able to confirm a density | concentration only with the dilution tank 1, an installation becomes more compact.

  The load cell 4 is an instrument that measures the amount of liquid in the dilution tank 1. By providing the load cell 4, the liquid amount in the dilution tank 1 can be managed. In addition, not only a load cell but a liquid level gauge etc. may be used.

  The ultrapure water tank 5 is a water tank in which ultrapure water as a diluent is stored, and supplies ultrapure water to the dilution tank 1 through a pipe. The piping connecting the ultrapure water tank 5 and the dilution tank 1 is provided with a regulating valve (second regulating means) 8, and the regulating valve 8 is ultrapure that is introduced into the dilution tank 1 by opening and closing thereof. Adjust the amount of water.

  The stock solution tank 6 is a water tank in which a stock solution of a developer as a chemical is stored, and supplies the stock solution of the developer to the dilution tank 1 through a pipe. The piping connecting the stock solution tank 6 and the dilution tank 1 is provided with a regulating valve (first regulating means) 9, and the regulating valve 9 opens and closes the developer introduced into the dilution tank 1. Adjust the volume of the stock solution.

  The dilution apparatus in the present embodiment is further provided with a programmable controller (control means) 7. The programmable controller 7 is a control device that controls the opening and closing of the control valves 8 and 9 based on the measured values in the densitometer 3 and the load cell 4, and the densitometer 3, the load cell 4, and the control valve 8 and 9 is connected. The signal line is indicated by a dotted line in FIG.

  Below, the method to control opening and closing of the control valves 8 and 9 by the programmable controller 7 is demonstrated.

  A desired concentration of the developer is input to the programmable controller 7 in advance. The “desired concentration” is a desired concentration of the drug in a solution that is finally obtained by diluting using the diluting device of the present invention.

  The programmable controller 7 receives from the densitometer 3 a measured value of the concentration of the developer in the liquid in the dilution tank 1.

  Next, the programmable controller 7 controls the opening and closing of the control valves 8 and 9 so as to bring the measured value close to the desired concentration based on the measured value and the desired concentration of the developer input in advance. That is, the programmable controller 7 compares the measured value with the desired concentration, and if they are different, the ultrapure to be introduced into the dilution tank 1 so that the measured value approaches the desired concentration. Calculate the amount of water and the amount of the stock solution of the developer. And based on this calculated quantity, the signal for controlling opening and closing of the control valves 8 and 9 is transmitted.

  Next, the control valves 8 and 9 are opened and closed in accordance with a signal from the programmable controller 7. Thereby, the amount of ultrapure water introduced into the dilution tank 1 and the amount of the stock solution of the developer can be adjusted.

  As described above, in the dilution apparatus according to the present embodiment, the programmable controller 7 controls the opening and closing of the control valves 8 and 9 to correct the concentration of the developer in the liquid in the dilution tank 1 so as to approach a desired concentration. be able to. It is also possible to correct the concentration of the developer in the liquid in the dilution tank 1 to be equal to a desired concentration by repeating the control by the programmable controller 7 described above. As described above, since the concentration of the medicine can be accurately corrected by the programmable controller 7, the medicine can be diluted accurately.

  Further, the programmable controller 7 receives the measured value of the liquid amount in the dilution tank 1 from the load cell 4. As a result, the amount of ultrapure water introduced and the amount of the stock solution of the developer can be accurately measured, and the ultrapure water introduced so that the amount of liquid in the dilution tank 1 does not exceed its capacity. And the amount of the developer stock solution can be adjusted. Therefore, the liquid amount in the dilution tank 1 can be managed suitably.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The diluting apparatus according to the present invention can prevent impurities from being mixed, and the equipment is compact. Therefore, it is suitable for diluting a drug such as a stock solution of a developing solution, and for various manufacturing processes using the diluted drug. Can be used.

1 Dilution tank (container)
2 Magnetic levitation pump 3 Densitometer 4 Load cell 5 Ultrapure water tank 6 Stock solution tank 7 Programmable controller (control means)
8 Control valve (second adjusting means)
9 Control valve (first adjusting means)

Claims (3)

A drug diluting device comprising a container into which a drug and a diluent are introduced,
A drug dilution apparatus, wherein the container is provided with a magnetic levitation pump for stirring the liquid in the container.   The dilution apparatus according to claim 1, further comprising a concentration meter that measures the concentration of the drug in the liquid in the container. First adjusting means for adjusting the amount of the drug introduced into the container;
Second adjusting means for adjusting the amount of the diluent introduced into the container;
A first adjustment means and a second adjustment are received so as to bring the measured value closer to the desired concentration based on the measured value and the desired concentration of the medicine inputted in advance. Control means for controlling the means;
The dilution apparatus according to claim 2, further comprising:

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