JP5248209B2 - Chemical recovery device and chemical recovery method - Google Patents

Description

  The present invention provides a chemical solution receiving member suitable for separating a collected chemical solution that does not contain a cleaning solution and a waste chemical solution that contains a cleaning solution when collecting a used chemical solution by chemical treatment, a chemical solution recovery apparatus and a chemical solution recovery using the same In particular, a chemical solution receiving member and a chemical solution recovery device that are particularly suitable when the used chemical solution is a semiconductor polishing slurry (hereinafter abbreviated as a polishing slurry) used in a polishing process of a semiconductor manufacturing process. And a chemical recovery method.

  The above-mentioned semiconductor manufacturing process includes a process for making basic materials such as glass for wafers, liquid crystals, and masks and a manufacturing apparatus member for those materials, and a device manufacturing process for processing these materials to produce elements and patterns. .

  In recent years, with the increase in the speed of computers, semiconductor integrated circuits (ICs) used in computers have been required to have a higher degree of integration. In order to adapt to such high integration of ICs, it is indispensable to adopt a multilayer laminated structure together with miniaturization of wiring patterns.

  In order to employ a multilayer stack structure, the unevenness of each layer of the wafer itself and the multilayer stack structure as a base material is made smaller than before, and the coverage (step coverage) at the step portion during film formation is deteriorated and lithography is performed. It is necessary to avoid problems such as fluctuations in the coating thickness of the photoresist in the process.

  In order to eliminate unevenness of each layer in such a multilayer laminated structure, the wafer as a base material and the surface of each layer formed on the wafer are polished using a polishing slurry.

  In addition, when forming contact holes or via holes by CVD (chemical vapor deposition) using tungsten W, or when embedding copper Cu in the damascene structure by plating, a tungsten film or copper film formed on the surface is used. The tungsten film or copper film formed on the surface leaving only the hole part and the damascene structure part is polished until it becomes flush with the surrounding insulating film. In this case as well, polishing using a polishing slurry is performed.

  In general, in a polishing process in a semiconductor manufacturing process, the surface of a wafer attached to a spindle is brought into contact with a polishing pad on the surface of a rotary table, and polishing is performed by rotating the rotary table while supplying polishing slurry to the contact portion. It is.

  The polishing slurry used in this polishing step is to disperse abrasives such as fumed silica in ultrapure water and dissolve components such as oxidizing agents such as hydrogen peroxide, iron salts, and organic acids depending on the purpose. A special composition is used. When the polishing process is completed, the polished wafer is cleaned with ultrapure water, and the used polishing slurry adhering to the wafer and the polishing apparatus is flowed together with the cleaning liquid and stored in the recovery tank.

  The used polishing slurry collected in the collection tank is adjusted in concentration by removing excess water with a ceramic filter, the ionic components are removed by ion exchange resin, etc., and the components lacking relative to the original composition are replenished Further, excessive particles such as removed polishing waste are removed through a particle size adjusting filter and reused as a polishing slurry (see, for example, Patent Document 1).

  However, in order to regenerate a polishing slurry that has been diluted very thinly by washing with ultrapure water, it is necessary to remove the ultrapure water used for washing, which is not costly and laborious. It took extra.

  Therefore, a recent method for regenerating the polishing slurry is to collect only the polishing slurry after being used for polishing in a storage tank and subject it to a regeneration process. The polishing slurry remaining on the polishing pad is washed with washing water. This was done by storing it in a waste tank and then discarding it. In other words, only the polishing slurry that has a concentration close to that of an unused polishing slurry and is easy to regenerate is collected, and the one mixed with a large amount of washing water is discarded, and work efficiency and overall cost are emphasized.

Here, the polishing slurry to be regenerated and the polishing slurry to be discarded are separated by changing the storage tank to which the liquid is fed between the polishing step and the cleaning step, but the timing of the change is too early. In this case, the polishing slurry useful for regeneration is discarded, and the regeneration efficiency is lowered. If it is too slow, the cleaning water is mixed in the slurry for regeneration and diluted to lower the overall concentration. Then, it is possible to recover the polishing slurry more efficiently by solving this problem, and measure the conductivity or pH of the used polishing slurry, and based on the measured value, the polishing slurry for regeneration A polishing slurry recovery method and recovery device for separating the slurry from the polishing slurry for disposal have already been filed and known by the present applicant (see, for example, Patent Document 2).
JP-A-11-010540 JP 2007-319974 A

  The above-described conventional method for reclaiming polishing slurry is to measure the properties of the polishing slurry that is actually flowing during recovery in order to separate the regenerated polishing slurry from the discarded polishing slurry. Since the switching timing is determined in step 1, it is possible to efficiently recover the polishing slurry that does not contain extra cleaning water and can be efficiently regenerated only by adjustment with a slight correction liquid It is.

  However, even when such a recovery method is used, the tank for sending the polishing slurry for regeneration or disposal is switched by a pipe, and the valve disposed in the middle of the pipe is used. Depending on the position where the sheath is provided, it may take time to adjust the switching timing. Further, when a valve trouble occurs, there is a possibility that a large amount of the polishing slurry for disposal is mixed in the polishing slurry for regeneration.

  Therefore, in view of the above-described problems, the present invention separates a chemical solution that is useful for regeneration and a chemical solution that is not suitable for regeneration into a used chemical solution by using an efficient and simple device configuration. A chemical solution recovery apparatus and a chemical solution recovery method that can be separately collected are provided.

  As a result of diligent research to solve such problems, the present inventors have developed a chemical liquid receiving member having a chemical liquid storage part that can store a predetermined amount of chemical liquid when collecting used chemical liquids. In addition, the present inventors have found that the used chemical liquid can be regenerated with a simple apparatus configuration by using a separate apparatus for separating and discarding chemical liquid.

  That is, the chemical solution receiving member of the present invention includes a chemical solution inlet into which the chemical solution flows, a chemical solution storage unit capable of storing a predetermined amount of the chemical solution flowing in from the chemical solution inlet, and a chemical solution that exceeds the predetermined amount of the chemical solution storage unit. And a chemical solution discharge port for discharging water.

  Moreover, the chemical solution recovery apparatus of the present invention includes a chemical solution inlet into which a chemical solution flows, a chemical solution storage unit capable of storing a predetermined amount of the chemical solution flowing in from the chemical solution inlet, and a chemical solution that exceeds a predetermined amount of the chemical solution storage unit. A chemical solution receiving member having a chemical solution discharge port, a chemical solution recovery pump for sucking the collected chemical solution stored in the chemical solution storage unit, a recovery tank for storing the collected chemical solution sucked by the chemical solution recovery pump, and a chemical solution discharge port And a waste tank for storing the discharged chemical solution.

  Further, the chemical solution recovery method of the present invention includes a chemical solution inlet into which a chemical solution flows, a chemical solution storage unit capable of storing a predetermined amount of the chemical solution flowing in from the chemical solution inlet, and a chemical solution that exceeds a predetermined amount of the chemical solution storage unit. When the used chemical solution is allowed to flow into a chemical solution receiving member having a chemical solution discharge port, and the collected chemical solution that does not contain the cleaning solution is flowing into the chemical solution receiving member, the recovery stored in the chemical solution storage unit When the chemical solution is sucked and collected by the chemical solution recovery pump, and the waste chemical solution containing the cleaning liquid is flowing into the chemical solution receiving member, the suction operation of the chemical solution recovery pump is stopped, and the waste chemical solution is discharged from the chemical solution outlet. It is characterized by collecting.

First, the chemical solution receiving member of the present invention will be described.
The chemical solution receiving member of the present invention, as described above, exceeds the predetermined amount of the chemical solution inlet, the chemical solution inlet that stores the chemical solution, the chemical solution storage portion that can store the chemical solution flowing in from the chemical inlet, And a chemical solution outlet for discharging the chemical solution.

  In this chemical solution receiving member, when the used chemical solution is introduced from the inflow port of the chemical solution receiving member, the chemical solution moves downward through the inside of the chemical solution receiving member mainly along the inner wall. At this time, since the chemical solution receiving member has a chemical solution storage portion that can store a predetermined amount of the chemical solution, the chemical solution does not simply pass through the inside of the chemical solution receiving member but is temporarily held in the chemical solution storage portion. The

  Further, when the chemical liquid further flows in and the chemical liquid exceeding the capacity of the chemical liquid storage part flows, the chemical liquid overflows from the chemical liquid storage part and is discharged from the chemical liquid outlet provided separately from the chemical liquid inlet. Has been. That is, this chemical solution receiving member can automatically discharge a chemical solution that exceeds the capacity of the chemical solution storage section.

  At this time, the chemical solution outlet is provided at a position that is the same height as or lower than the chemical solution inlet in the vertical direction. By doing in this way, the storage amount of a chemical | medical solution can be controlled by the structure of a chemical | medical solution receiving member. If the chemical solution outlet is higher than the chemical solution inlet, the chemical solution is not discharged even if it fills the chemical solution storage part, and the discharge control of the chemical solution becomes impossible.

  Next, a chemical solution recovery apparatus and a chemical solution recovery method using such a chemical solution receiving member will be described.

  The chemical solution recovery device of the present invention contains the above-described chemical solution receiving member of the present invention, a chemical solution recovery pump that sucks the collected chemical solution stored in the chemical solution storage part of the chemical solution receiving member, and the recovered chemical solution sucked by the chemical solution recovery pump A recovery tank and a waste tank for storing the waste chemical liquid discharged from the chemical liquid discharge port.

  Here, the chemical liquid recovery pump of the present invention sucks the collected chemical liquid stored in the chemical liquid storage part in the chemical liquid receiving member, and the type thereof is not particularly limited, but when all the chemical liquid has been sucked, It is preferable that it is a self-contained type that does not affect its performance even if it is sucked, and a piezo pump is particularly preferable. The piezo pump is a lightweight and small-sized pump that adjusts electrical signals such as voltage, frequency, and waveform to operate the piezoelectric element, and has good response performance.

  In addition, the recovery tank of the present invention can store the recovered chemical liquid sucked by the chemical recovery pump, and the waste tank only needs to be able to store the waste chemical liquid, and contaminates the recovered chemical liquid and the waste chemical liquid, respectively. The material, shape, etc. are not particularly limited as long as they can be stably housed without any problems.

  And the chemical | medical solution collection | recovery method of this invention is the chemical | medical solution inlet which a chemical | medical solution flows in, the chemical | medical solution storage part which can store the predetermined amount of the chemical | medical solution which flowed in from the chemical | medical solution inlet, and the chemical | medical solution which exceeded the predetermined amount of the chemical | medical solution storage part When the used chemical solution is allowed to flow into a chemical solution receiving member having a chemical solution discharge port, and the collected chemical solution that does not contain the cleaning solution is flowing into the chemical solution receiving member, the recovery stored in the chemical solution storage unit When the chemical solution is sucked and collected by the chemical solution recovery pump, and the waste chemical solution containing the cleaning liquid is flowing into the chemical solution receiving member, the suction operation of the chemical solution recovery pump is stopped, and the waste chemical solution is discharged from the chemical solution outlet. It is to be collected.

  Here, the kind of chemical solution that can be applied to the members, apparatuses, and methods described above is not particularly limited, but specific usage conditions are required for the method of using the chemical solution.

  First of all, it is necessary to clearly separate the operation by using the chemical solution and the operation by cleaning the chemical solution. In this way, when the operation is clear, it is possible to clearly distinguish the chemical liquid to be recovered from the liquid that the cleaning liquid does not contain and the liquid that the cleaning liquid contains. The feature of the recovery method of the present invention is that the recovered chemical solution and the waste chemical solution can be easily operated by using the fact that the recovered chemical solution and the waste chemical solution are greatly different in the flow rate per time depending on whether or not the cleaning solution is used. It is in the point which is sorted by.

  That is, in the collected chemical solution, the used chemical solution flows into the chemical solution receiving member as it is, but in the waste chemical solution, the cleaning operation is performed by supplying a larger amount of the cleaning solution than the supply amount of the chemical solution. At this time, the flow rate of the waste chemical solution flowing into the chemical solution receiving member is clearly larger than the flow rate of the recovered chemical solution, and the flow rates are greatly different between the two.

  In the present invention, the chemical liquid stored in the chemical liquid storage part is sucked by the chemical liquid recovery pump.At this time, the recovered chemical liquid is adjusted by adjusting the capacity that can be stored in the chemical liquid storage part and the amount sucked by the chemical liquid recovery pump. It can be used for playback without leaking. For example, when a chemical solution is continuously supplied, almost the same amount of used chemical solution flows into the chemical solution storage section. At this time, the suction amount of the chemical solution recovery pump is reduced. By making the supply amount or the inflow amount the same or slightly larger, the recovered chemical solution can be recovered to the recovery tank without being discarded.

  Then, when the treatment with the chemical solution is completed and the chemical solution that adheres to the object to be processed and the like is washed, the supply of the chemical solution is stopped, and the chemical solution is washed away by supplying the cleaning solution instead. The chemical liquid washed away at this time contains a cleaning liquid. Therefore, in order to collect and regenerate this, the cleaning liquid contained in a large amount must be removed from the chemical solution, which takes extra time and cost. Therefore, the chemical liquid containing the cleaning liquid is disposed of without being recycled as a waste chemical liquid.

  Cleaning is performed in this manner, and when the waste chemical solution flows into the chemical solution receiving member, the chemical solution recovery pump is stopped so that the waste chemical solution is not mixed with the recovered chemical solution. In addition to stopping the chemical solution recovery pump, as described above, since the supply amount of the cleaning liquid is usually larger than the supply amount of the chemical solution, the chemical solution storage part is immediately filled with the waste chemical solution and automatically overflows. Most of the waste chemical solution is discharged from the chemical solution outlet and stored in the waste tank.

  Here, the supply amount of the cleaning solution used in the cleaning of the chemical solution is preferably large in order to wash away the chemical solution. For example, the supply amount of the cleaning solution is preferably 3 times or more, preferably 5 times or more with respect to the supply amount of the chemical solution. More preferred. However, if a large amount of cleaning solution is used unnecessarily, the amount of waste chemical solution becomes large, and the disposal takes time and cost. Therefore, it is particularly preferably about 8 to 12 times.

  And the process by this chemical | medical solution and washing | cleaning operation can also be performed repeatedly, respectively. That is, after the first chemical treatment and the cleaning treatment, the second chemical treatment and the washing treatment are performed, and the third and fourth treatments are repeated.

  In such a case, in the chemical solution recovery apparatus and the chemical solution recovery method of the present invention, it is preferable to further include a waste pump that sucks the waste chemical solution stored in the chemical solution storage unit. The waste pump is not particularly limited as is the case with the chemical recovery pump, but is preferably a self-contained type and particularly preferably a piezo pump.

  The waste pump sucks the waste chemical liquid stored in the chemical liquid storage section after the inflow of the waste chemical liquid to the chemical liquid receiving member stops and before the recovered chemical liquid flows. In this way, by sucking the waste chemical solution with the waste pump and leaving the chemical solution storage portion empty, the chemical solution that is used in the next chemical treatment and can be recovered without being contaminated with the waste chemical solution. .

  As described above, according to the recovery device and the recovery method of the present invention, the recovered chemical solution and the waste chemical solution can be efficiently and easily separated without switching valves or using a complicated device. . In addition, the recovery device and the recovery method are characterized by using the chemical solution receiving member of the present invention. Even when this chemical solution receiving member is applied to an existing device, a new pipe is provided as in the prior art. There is no need to modify the large-scale device, and it is only necessary to install the chemical solution receiving member at the inlet of the used chemical solution, and install the chemical solution recovery pump and the waste pump.

  In the present invention, the chemical solution to be collected is not particularly limited, but is particularly preferably a polishing slurry. Hereinafter, a preferable polishing slurry will be described.

  Typical polishing slurries are those disclosed in JP-A-10-265766 and JP-A-11-116948. Specifically, for example, fumed silica fine particles having a particle size distribution (median diameter) volume reference of 0.02 μm or more and a volume standard of about 0.15 μm, an oxidizing agent such as hydrogen peroxide, ferric nitrate, organic acid, amino acid Etc. are dispersed or dissolved in water.

An example of the composition of the unused polishing slurry is shown below.
Specific gravity 1.03
pH 2.0-2.2
Average particle size [μm] 0.14 to 0.15
W concentration [ppm] <10
Fe concentration [ppm] 60
Ti concentration [ppm] <0.1
B concentration [ppm] <0.2
Na concentration [ppm] <0.1
Mg concentration [ppm] 0.6
Al concentration [ppm] 0.1
K concentration [ppm] <0.1
Ca concentration [ppm] 0.1
Mn concentration [ppm] 0.1
Cr concentration [ppm] 0.1
Mn concentration [ppm] 0.1
Ni concentration [ppm] <0.1
Cu concentration [ppm] <0.5
Zn concentration [ppm] <0.1
Pb concentration [ppm] <1
Co concentration [ppm] <0.1
Zr concentration [ppm] <0.1
Cr concentration [ppm] <10
TOC concentration [ppm] 160-230

  The polishing slurry having the above composition contains a specific metal ion depending on the composition of the object to be polished by being used in the semiconductor polishing step. As it is, it is accommodated in the recovery tank from the chemical receiving member. Then, when the polishing process is finished, in the cleaning process, the polishing slurry, polishing debris and the like remaining on the polishing pad are cleaned with a cleaning liquid made of ultrapure water, and this is stored in a waste tank.

  That is, a large amount of cleaning water is mixed in the used polishing slurry stored in the recovery tank during polishing in the semiconductor polishing process and the used polishing slurry stored in the waste tank in the cleaning process. It depends on whether or not it is.

  The polishing slurry mixed with the washing water, when trying to regenerate it, first has to be operated to remove a large amount of water. Further, the amount of polishing slurry contained at this stage was small relative to the amount of waste liquid to be treated, and even if it was regenerated, the efficiency was poor.

  Therefore, by applying the chemical solution regeneration method of the present invention, it is possible to make maximum use of polishing slurry that has not been diluted by mixing cleaning water or polishing slurry that has a small amount of mixing. The recovered polishing slurry thus recovered can be reused as a polishing slurry by subjecting it to a regeneration operation as described later.

According to the chemical solution receiving member of the present invention, it is possible to easily separate a used chemical solution for recovery and disposal by its flow rate.
And according to the chemical solution recovery method and the chemical solution recovery apparatus of the present invention, the chemical solution receiving member having such a specific structure allows easy use of a chemical solution useful for regeneration and the like mixed with a large amount of cleaning liquid. With a simple operation, it can be separated and collected with a simple apparatus configuration.

  Since this device can eliminate the dead space as in the case of using conventional automatic valves and branch pipes, it reduces the problem of contamination with other types of chemicals and waste chemicals attached to the pipes, etc. The chemical solution can be collected efficiently. And the chemical | medical solution collect | recovered in this way can perform operations, such as subsequent reproduction | regeneration efficiently.

Next, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1 is a plan view of a chemical solution receiving member according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line AA of the chemical solution receiving member of FIG. 1, and FIG. 3 is a chemical solution to which the chemical solution receiving member of FIG. It is the figure which showed schematic structure of the collection | recovery apparatus.

  First, the chemical liquid receiving member 1 shown in FIG. 1 and FIG. 2 includes a chemical liquid inlet 2 through which the flowing chemical liquid flows into the inside thereof, a chemical liquid storage unit 3 that can store the flowed chemical liquid, and a chemical liquid reservoir. It is comprised from the chemical | medical solution discharge port 4 from which a chemical | medical solution is discharged | emitted outside when the capacity | capacitance which can be accommodated in the part 3 is exceeded.

  Further, the chemical solution recovery device 21 is applied with the above-described chemical solution receiving member 1, and the chemical solution receiving member 1, the collection container 22 for collecting the used chemical solution, and the chemical solution storage part 3 of the chemical solution receiving member 1 are used. A chemical recovery pump 23 for aspirating the stored recovered chemical liquid, a recovery tank 24 for storing the recovered chemical liquid suctioned by the chemical recovery pump 23, and a waste tank for storing the waste chemical liquid discharged from the chemical outlet 4 of the chemical receiver 1 25.

  In the present embodiment, the platen 31, the silicon wafer 32, and the head 33 are illustrated in order to describe the case where the present invention is applied to the recovery of the polishing slurry used when polishing the semiconductor wafer.

  When the semiconductor polishing process is started, polishing slurry is supplied onto the platen 31 to polish the silicon wafer 32. At this time, the semiconductor polishing rotates the head 33 that fixes the platen 31 and the silicon wafer 32, respectively. Therefore, the polishing slurry is blown to the outside mainly by the centrifugal force of the platen 31. Around the platen 31, a recovery container 22 for receiving the used polishing slurry and the cleaned polishing slurry is disposed. The skipped polishing slurry is accommodated in the recovery container 22.

  During the polishing, the polishing slurry is continuously supplied, and the polishing slurry that has flowed down is stored in the collection container 22. The collection container 22 is formed with an inclined bottom so that the stored polishing slurry is collected in the chemical solution receiving member 1. Therefore, the slurry for polishing, which is the recovered chemical solution that has flowed down, flows in one after another from the chemical solution inlet 2 of the chemical solution receiving member 1 and accumulates in the chemical solution storage unit 3. The chemical liquid that has started to accumulate in the chemical liquid storage unit 3 is sucked by the chemical liquid recovery pump 23 and stored in the recovery tank 24. At this time, the chemical liquid is not discharged from the chemical liquid discharge port 4.

  Then, when the polishing of the semiconductor wafer 32 is completed, the supply of the polishing slurry is stopped, and then the cleaning liquid is supplied by supplying ultrapure water to clean the platen 31, the head 33 and the semiconductor wafer 32. Rinse away. At this time, the chemical solution and the ultrapure water that is the cleaning solution are mixed to reduce the concentration of the chemical solution, resulting in a waste chemical solution that is not suitable for regeneration. This waste chemical solution flows down to the recovery container 22 and is collected in the chemical solution receiving member 1 in the same manner as the above-described recovered chemical solution.

  At this time, the suction of the chemical solution recovery pump is stopped before the waste chemical solution flows into the chemical solution receiving member 1 so that the waste chemical solution is not mixed with the recovered chemical solution. Waste chemical liquid that is not aspirated accumulates in the chemical liquid reservoir 3 and eventually overflows. The overflowing chemical solution overflowed is discharged from the chemical solution outlet 4 and stored in the waste tank 25. At this time, since the chemical solution discharge port 4 is formed at a position lower in the vertical direction than the chemical solution inlet port 2, the waste chemical solution is always discharged from the chemical solution discharge port 4 when the capacity of the chemical solution storage part is full. The

  In this way, the collected chemical solution and the waste chemical solution can be efficiently separated by a simple operation of switching the operation of the chemical solution recovery pump using a chemical solution receiving member having a specific structure.

  Note that the capacity of the chemical solution storage part of the chemical solution receiving member 1 may be set as appropriate so that the collected chemical solution is not stored in the waste tank 25 in consideration of the suction capability of the chemical solution recovery pump. For example, the volume is preferably 50 to 400 mL, and more preferably 100 to 200 mL. This is because, in the case of semiconductor polishing, it is considered as a typical example that the supply amount of the polishing slurry is 100 to 200 mL / min and the suction amount of the chemical solution recovery pump is approximately the same.

  In addition, a pump that can be used as a chemical solution recovery pump at this time is not particularly limited. However, since it is conceivable that air is sucked when all the chemical solution is sucked, there is no problem even if gas is sucked. A pump is preferred. In particular, a pump having a piezo structure capable of sucking liquid by vibrating a piezoelectric vibrator is particularly preferable.

  One chemical solution recovery pump may be used, but two or more chemical solution recovery pumps may be used. When two or more are used, even if one of the pumps malfunctions when used in parallel, the operation can be continued without stopping the apparatus. Further, when used in series, for example, when one pump is clogged with particles such as shavings, the other pump can be operated to eliminate the clogging.

  The chemical recovery pump stops its operation according to the inflow of the recovered chemical and waste chemical so that the waste chemical does not enter the recovery tank 24. The timing of stopping the operation is a cleaning operation. It is preferable that after a predetermined time elapses until the waste chemical solution flows into the chemical solution receiving member 1 after starting the operation.

  However, when the operation is stopped by such an operation, there is a possibility that the waste chemical solution flows faster than usual and contaminates the recovered chemical solution, or it flows later and the recovery amount of the recovered chemical solution may increase. However, it cannot be handled at all.

  Therefore, it is preferable to incorporate a sensor for determining the property of the chemical liquid flowing into the chemical liquid receiving member 1, and to determine whether or not to stop the operation of the chemical liquid recovery pump from the detection result of this sensor. Examples of the sensor that can be used at this time include a conductivity meter, pH meter, viscometer, refractometer, and turbidimeter.

  Measuring the conductivity, pH, viscosity, refractive index, turbidity, etc. of the used polishing slurry is particularly effective for seeing changes in the properties of the polishing slurry, and how much cleaning water is in the polishing slurry. Can be easily determined by calculating the measured value.

  That is, since the conductivity, pH, viscosity, refractive index, turbidity, etc. have a significant effect on the degree of contamination of the cleaning water into the polishing slurry, the cleaning water is not mixed or the amount of mixing is small. The polishing slurry that can be easily regenerated and the polishing slurry that contains a large amount of washing water and takes time to regenerate can be easily discriminated from these measured values.

  For example, for a mixed liquid of polishing slurry and ultrapure water, the relationship between the slurry concentration and the conductivity is 100%, that is, the conductivity of the unused polishing slurry before being used for semiconductor polishing is This indicates about 200 mS / m, and ultrapure water as cleaning water is mixed therein, so that the concentration (ratio) of the polishing slurry decreases and the conductivity decreases, and this relationship has linearity. That is, by observing the change in conductivity, the change in the concentration of the polishing slurry can be seen, and the concentration of the polishing slurry at the time of measurement can be confirmed.

  Thus, it becomes possible to easily discriminate between the polishing slurry suitable for regeneration and the polishing slurry that requires time for regeneration, and the polishing slurry suitable for regeneration is then recovered for the regeneration step. The polishing slurry, which takes time to regenerate in the tank, is separately collected in a waste tank that is discarded as it is.

  Here, as a predetermined value used as a reference for separating the recovery tank and the waste tank, the conductivity of the polishing slurry is preferably 100 to 200 mS / m, and particularly preferably 170 to 200 mS / m. Moreover, when it is going to remove | eliminate mixing of washing water strictly, you may set 200 mS / m or more as a predetermined value. In this embodiment, when the predetermined value or more is set, the operation of the chemical recovery pump is continued to be sent to the recovery tank, and when it is less than the predetermined value, the chemical recovery pump is stopped and stored in the waste tank. It is comprised as follows.

  Further, in the case of measuring pH, it may be configured to measure pH instead of the above-mentioned conductivity. At this time, the change in pH is caused by dilution of acidic polishing slurry by mixing water, The pH will increase. Here, as a predetermined value used as a reference for separating the recovery tank and the waste tank, the polishing slurry preferably has a pH of 2.3 to 2.6, and may be 2.3 or less. In the case of pH, if the chemical liquid recovery pump is below the predetermined value, the operation of the chemical liquid recovery pump is continued to be sent to the recovery tank, and if the predetermined value is exceeded, the chemical liquid recovery pump is stopped and stored in the waste tank. It is comprised as follows.

  In addition, when measuring the viscosity, it may be configured so that the viscosity is measured instead of the above conductivity. At this time, the change in the viscosity is caused by dilution of the polishing slurry by mixing with water, and the viscosity decreases. Will be. As a reference value for fractionation, the viscosity of the polishing slurry is preferably 2 to 3 cp.

  Further, in the case of measuring the refractive index, it may be configured to measure the refractive index instead of the electrical conductivity. At this time, the change in the refractive index is caused by the mixing of water and the polishing slurry is diluted. The refractive index will decrease. As a reference value for sorting, it is preferable that the refractive index of the polishing slurry is 1.4 to 1.45.

  In addition, when measuring turbidity, it may be configured to measure turbidity instead of the above-described conductivity. At this time, the change in turbidity is caused by dilution of the polishing slurry by mixing water. Turbidity will decrease. As a reference value for separation, the turbidity of the polishing slurry is preferably 300 to 600 NTU, and may be 600 NTU or more.

  Furthermore, in the above description, a case where one type of chemical solution is used is described. However, when processing is performed using two or more types of chemical solutions, a chemical solution recovery pump and a recovery tank are provided for each type of chemical solution. do it.

  Here, the polishing slurry accommodated in the waste tank is usually discarded. However, if the recovery amount is prioritized even if it takes time, it is possible to recycle it as a polishing slurry by concentrating it with a ceramic filter and subjecting it to a regeneration operation.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a diagram showing a schematic configuration of another chemical solution recovery apparatus to which the chemical solution receiving member of FIG. 1 is applied.

  The chemical solution recovery device 41 shown in FIG. 4 applies the chemical solution receiving member 1 described above, and stores the chemical solution receiving member 1, a collection container 22 for collecting used chemical solutions, and the chemical solution storage of the chemical solution receiving member 1. Contains a chemical recovery pump 23 for aspirating the collected chemical stored in the unit 3, a recovery tank 24 for storing the recovered chemical aspirated by the chemical recovery pump 23, and a waste chemical discharged from the chemical outlet 4 of the chemical receiver 1 And a waste pump 42 that sucks the recovered chemical stored in the chemical storage section 3 of the chemical receiver 1.

  The chemical solution recovery apparatus 41 shown here is provided with a waste pump 42, sucks the waste chemical solution stored in the chemical solution storage section 3 of the chemical solution receiving member 1 by the waste pump 42, and sends the suctioned waste chemical solution to the waste tank 25. And it has the same structure as the chemical | medical solution collection | recovery apparatus demonstrated in 1st Embodiment except having made it accommodate. Hereinafter, description of the same configuration as that of the first embodiment will be omitted, and only differences will be described.

  In the first embodiment, the collected chemical solution and the waste chemical solution can be easily separated and collected. However, a semiconductor polishing process is not usually completed by a single operation, and a large amount of objects to be polished are processed by repeating each process of polishing and cleaning many times.

  Therefore, the state of the chemical solution receiving member 1 when the cleaning operation is completed in the first embodiment and the waste chemical solution is accommodated in the waste tank 25 is that the waste chemical solution is stored in the chemical solution storage unit 3. If this is directly entered into the next polishing operation, the recovered chemical solution that flows in next is contaminated by the waste chemical solution in the chemical solution storage section 3. In the first embodiment, even if it is contaminated in this way, it has only a capacity capable of holding the chemical solution in the chemical solution storage unit 3, and therefore the degree of contamination is low. It is preferable not to let this occur.

  Therefore, in the present embodiment, in order to solve the above-described problem of contamination by the waste chemical liquid, a waste pump 42 that can suck the chemical liquid stored in the chemical liquid storage unit 3 is provided in the same manner as the chemical liquid recovery pump. is there.

  In this waste pump, after the polishing-cleaning process is completed and the inflow of the waste chemical liquid into the chemical liquid receiving member 1 is stopped, the chemical liquid storage section starts from the next polishing process until the recovered chemical liquid flows in. The waste chemical stored in 3 is sucked. And the waste chemical | medical solution attracted | sucked here should just be accommodated in the waste tank 25. FIG.

  By newly providing a waste pump and sucking the waste chemical solution in this way, the recovered chemical solution that flows next can be recovered without being contaminated with the waste chemical solution.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG. FIG. 5 is a diagram showing a schematic configuration of still another chemical solution recovery apparatus to which the chemical solution receiving member of FIG. 1 is applied.

  The chemical solution collecting apparatus 51 shown in FIG. 5 is an application of the chemical solution receiving member 1 described above. The chemical solution receiving member 1, the collection container 22 for collecting used chemical solutions, and the chemical solution storage of the chemical solution receiving member 1. Contains a chemical recovery pump 23 for aspirating the collected chemical stored in the unit 3, a recovery tank 24 for storing the recovered chemical aspirated by the chemical recovery pump 23, and a waste chemical discharged from the chemical outlet 4 of the chemical receiver 1 And a cleaning liquid recovery pump 52 that sucks the cleaning liquid stored in the chemical liquid storage section 3 of the chemical liquid receiving member 1.

  The chemical recovery device 51 shown here is provided with a cleaning liquid recovery pump 52, and the cleaning liquid stored in the chemical storage part 3 of the chemical liquid receiving member 1 is sucked by the cleaning liquid recovery pump 52 and the suctioned cleaning liquid is sent to the cleaning liquid tank 53. And it has the same structure as the chemical | medical solution collection | recovery apparatus demonstrated in 1st Embodiment except having made it accommodate. Hereinafter, description of the same configuration as that of the first embodiment will be omitted, and only differences will be described.

  In the first embodiment, the collected chemical solution and the waste chemical solution are separated depending on whether or not the cleaning solution is contained, and all the cleaning solution contains is stored in the waste tank. However, the chemical liquid flowing into the chemical liquid receiving member 1 after the start of the cleaning operation is a mixture of the cleaning liquid and the chemical liquid. However, as the cleaning operation proceeds, the chemical liquid concentration gradually decreases.

  Therefore, chemicals that should be discarded at the initial stage of the cleaning operation, but those that flow in after the chemicals are almost cleaned are either low-concentration or no-solutions. For those having a high cleaning liquid concentration, it is possible to recover the collected liquid and use it again as a cleaning liquid.

  Therefore, in the present embodiment, a cleaning liquid recovery pump 52 that can suck the cleaning liquid stored in the chemical liquid storage unit 3 is provided in the same manner as the chemical liquid recovery pump.

  The cleaning liquid recovery pump may be operated after a predetermined time has elapsed since the cleaning operation started and the waste chemical liquid has flowed into the chemical liquid receiving member 1 or while confirming the properties of the flowing cleaning liquid. May be performed at a timing when a material that has been sufficiently washed and most of the material is recovered by the washing liquid and can be easily reused flows into the chemical liquid receiving member 1. The cleaning liquid sucked here may be stored in the cleaning liquid recovery tank 53.

  The type of the cleaning liquid recovery pump is not particularly limited as in the case of the chemical liquid recovery pump and the waste pump, but unlike the chemical liquid recovery pump and the waste pump, the amount supplied per unit time is large. In order to efficiently recover this, the pump is not particularly limited. Moreover, it is preferable that the suction amount is 600-3000 mL / min, and 1600-2400 mL / min is especially preferable.

  By newly providing a cleaning liquid recovery pump and recovering the reusable cleaning liquid in this way, not only the chemical liquid but also the cleaning liquid can be reused to reduce the cost.

(Fourth embodiment)
Next, a fourth embodiment will be described with reference to FIGS. Here, the variation of the chemical | medical solution receiving member used in 1st Embodiment is demonstrated.

  FIG. 6 shows a cross-sectional view of a chemical solution receiving member different from the chemical solution receiving member 1 used in the first embodiment.

  Here, the chemical liquid receiving member 11 of FIG. 6 is configured by a chemical liquid inlet 12, a chemical liquid storage unit 13, and a chemical liquid outlet 14, and the basic configuration is the same as that of the chemical liquid receiving member 1. The difference is that the chemical solution outlet 14 is provided at the same height as the chemical solution inlet 12.

  Thus, by providing the chemical solution discharge port 14 at a position higher in the vertical direction than the chemical solution receiving member 1, the capacity of the chemical solution storage unit 13 can be increased. For example, even if it is a chemical solution receiving member with the same external shape, the volume of the chemical solution storage part can be easily increased by changing the height of the chemical solution discharge port or changing the diameter of the chemical solution discharge port in addition to this. Can be changed.

  Therefore, the shape of the chemical solution receiving member can be appropriately changed in consideration of the supply amount of the chemical solution and the supply amount of the cleaning liquid. In the drawings of the present application, the outer diameter and the chemical solution discharge port are formed in a cylindrical shape, but of course, the present invention is not limited to this, and the chemical solution inlet, the chemical solution storage portion, and the chemical solution discharge portion are provided. As long as it is provided, it can take any shape.

  Moreover, the chemical | medical solution receiving cover as shown in FIG. 7 can also be used. The chemical solution receiving lid 5 shown here is a disc-shaped lid provided with a plurality of openings 5a. The chemical solution receiving lid 5 is used by being fitted into the chemical solution inlet of the chemical solution receiving member. In FIG. 8, the chemical solution receiving lid 5 is fitted into the chemical solution inlet 2 of the chemical solution receiving member 1. A side sectional view of the state is shown.

  The chemical solution flowing into the chemical solution receiving member by using the chemical solution receiving lid 5 flows into the chemical solution receiving member from the opening 5a. However, since the inlet is somewhat limited, a rough semiconductor scrap or the like is used. The frequency of not flowing in is improved. Further, a nozzle capable of sucking a chemical solution with a chemical solution recovery pump and / or a waste pump can be inserted into the opening 5a and fixed easily.

  Further, as shown in FIG. 9, a liquid reservoir 6 is provided in the immediate vicinity of the chemical inlet 2 of the chemical receiver 1, and a sensor 7 capable of measuring the properties of the used chemical stored in the liquid reservoir 6 is provided. It is possible to determine whether to use the collected chemical solution or the waste chemical solution based on the value measured by the sensor. Here, as described in the first embodiment, the sensor can be a conductivity meter, a pH meter, a viscometer, a refractometer, or a turbidimeter.

(Fifth embodiment)
Next, in the recovery method of the present invention, a case where the recovered recovered chemical is subjected to a regeneration operation will be described. FIG. 10 is a diagram showing a regeneration cycle using a regeneration device so that the polishing slurry recovered by the chemical recovery device of the present invention can be used again during polishing.

  The chemical solution regenerating apparatus 60 in this embodiment uses an ultraviolet irradiation device 61, a prefilter 62 having a pore diameter of 5 μm, and an ion exchange resin device obtained by collecting the polishing slurry obtained by collecting with the chemical solution collecting device 21 described in the first embodiment. Alternatively, the chelate formation processing device 63, the composition adjustment tank 64, and the particle size adjustment filter 65 are installed and configured to sequentially pass along the flow path. Of course, this can also be applied to those described in the second and third embodiments and those recovered by other chemical recovery devices.

  In this embodiment, the polishing slurry or the like recovered by the chemical recovery device is first decomposed by hydrogen irradiation in the ultraviolet irradiation device 61 and then sent to the pre-filter 62 and polished in the process of passing therethrough. Particulate impurities such as debris are removed.

  Next, the polishing slurry is sent to an ion exchange resin device or a chelate formation processing device 63, where metal ions and organic ions are removed, and the composition adjustment tank 64 has the same composition as the unused polishing slurry. An amount of the correction liquid having the same pH is added, and finally, the excessively large particle size of the interstitial material is removed by the particle size adjusting filter 65, and the regenerated polishing slurry is supplied again to the polishing apparatus.

  The above is an example in which the used polishing slurry is configured to remove metal ions after removing coarse particles, but the present invention is not limited to such a configuration example. For example, the chemical solution recovery device 21 → the ultraviolet irradiation device 61 → the ion exchange resin device or the chelate formation processing device 63 → the prefilter 62 → the composition adjustment tank 64 → the particle size adjustment filter 65 can be configured as follows.

  When the ultraviolet irradiation device 61 is provided in this manner, the oxidizing agent contained in the polishing slurry being processed is decomposed and removed, and it is possible to suppress the subsequent filtration membrane and the like from being deteriorated by the oxidizing agent. Also, at this time, if a filter with a specific aperture is provided after the UV irradiation device, tungsten colloidalized by UV irradiation and hydrogen peroxide can be removed with the filter, reducing the load on the chelate formation processing device. You can also.

Next, examples embodying the present invention will be described.
Example 1
In this example, the polishing slurry used in the step of flattening the semiconductor silicon wafer was recovered as follows using the chemical recovery apparatus shown in FIG. 4, and the polishing slurry recovery performance was evaluated.

  First, using a semiconductor polishing apparatus (manufactured by MAT, trade name: ARW-8C1MS), while supplying the slurry for polishing onto the rotary table at 200 mL / min, rotation of the platen and head was started 3 seconds later, After polishing the surface of the silicon wafer until 60 seconds passed from the start of the supply of the polishing slurry, all operations were stopped.

  Then, dressing was performed for 20 seconds while supplying the ultrapure water onto the rotary table at 2 L / min for 10 seconds to wash the rotary table.

  Simultaneously with the polishing of the silicon wafer, the used polishing slurry flows into the chemical receiver and is temporarily held in the chemical reservoir. Five seconds after that, the slurry was sucked at a flow rate of 400 mL / min by a chemical recovery pump (piezo pump; manufactured by Nitto Kohki Co., Ltd., trade name: Bimol pump), and the polishing slurry for regeneration was sucked for 60 seconds and stored in the recovery tank.

  During ultrapure water cleaning, immediately after stopping the chemical recovery pump, the disposal pump (piezo pump; Nitto Kohki Co., Ltd., product name: Bimol Pump) is started and the cleaning water is sucked and discarded at a flow rate of 400 mL / min. Housed in a tank. The washing water that has flowed into the drainage receiver before the waste pump is started is mixed with the polishing slurry held in the drainage receiver, and the amount exceeding the holding capacity of the drainage receiver is discharged from the drainage port 1. .

  The polishing slurry for regeneration contained in the recovery tank is measured by using a turbidimeter (manufactured by Central Science Co., Ltd., trade name: Turb 2100P type), and the turbidity of the unused polishing slurry (500 NTU). ) And evaluated. Further, the polishing slurry in which a large amount of the washing water contained in the waste tank was mixed was also evaluated for the concentration of the polishing slurry by observing the turbidity measured using a turbidimeter. These results are shown in Table 1.

  From this result, the polishing slurry stored in the recovery tank is a slurry having almost the same properties as the unused polishing slurry, and the polishing slurry mixed with the cleaning water stored in the waste tank has an extremely high concentration. It was diluted and cannot be directly used for the reproduction operation.

(Comparative Example 1)
Next, as a comparative example, using the conventional chemical solution recovery apparatus of FIG. 11, the silicon wafer was polished using the polishing slurry in the same manner as in the example, and the rotary table was cleaned with ultrapure water. In FIG. 11, the polishing slurry is also collected at one point by the collection container 72 that collects the used polishing slurry scattered in the polishing process, and the collected polishing slurry flows through the pipe as it is and is collected. In the case of a chemical solution, it is sucked by the pump 73 and stored in the recovery tank 74, and in the case of a waste chemical solution, it is sucked by the pump 75 and stored in the waste tank 76.

  The used polishing slurry obtained by polishing the silicon wafer is held in the recovery container 72, and after 5 seconds from the start of the polishing apparatus, the pump 73 is started for 60 seconds to recover the used slurry in the recovery tank 74, and the polishing apparatus 5 seconds after the pump stopped, the pump 73 was stopped.

  Then, 20 seconds after the start of cleaning with ultrapure water, the pump 75 was started, and the chemical solution diluted with the cleaning water flowing into the recovery container 72 was recovered in the waste tank 76.

  The used polishing slurry contained in the collection tank 74 was evaluated by its turbidity in the same manner as in the example. Further, the polishing slurry mixed with a large amount of the washing water stored in the waste tank 76 was also evaluated by looking at the turbidity measured using a turbidimeter. These results are shown in Table 1 together with the examples.

  As shown in Table 1, the turbidity of the polishing slurry recovered in the recovery tank was 87.4% higher than that of the polishing slurry recovered in the example when the example and the comparative example were compared.

  In addition, the polishing slurry recovered in the waste tank showed a turbidity value that was 90% lower than that of the polishing slurry recovered in the example when the example and the comparative example were compared.

(Example 2)
The same operation as in Example 1 was performed except that the chemical solution receiving member shown in FIG. 9 was used, and the chemical solution was collected while measuring the turbidity flowing into the chemical solution receiving member with a turbidimeter. At this time, with regard to recovery and disposal, when the turbidity is 400 NTU, the chemical solution recovery pump and the disposal pump are switched. The turbidimeter used at this time was the same as that in Example 1.
This operation was repeated 5 times, and the recovered amounts of polishing slurry and pure water at that time are shown in Table 2, FIG. 12 and FIG.

(Comparative Example 2)
In the chemical solution recovery apparatus of FIG. 11, a turbidimeter was provided in the portion flowing from the polishing slurry collection container 72 into the pipe in the same manner as in Example 2, and the chemical solution was recovered in the same manner as in Comparative Example 1. At this time, the criteria for recovery and disposal were the same as those in Example 2, and the chemical solution recovery pump and the waste pump were switched.
This operation was repeated 5 times, and the recovered amounts of polishing slurry and pure water at that time are shown in Table 2, FIG. 12 and FIG.

  From the above results, it was found that by using the present invention, the polishing slurry can be recovered at a high concentration, that is, in a state close to the properties of the unused polishing slurry. It was also found that the cleaning water can be recovered while minimizing the mixing of excess polishing slurry.

  Therefore, according to the present invention, it is possible to efficiently recover a chemical solution suitable for regeneration with a simple operation and a simple apparatus configuration. And the system recovered by the present invention can recover the chemicals used in the semiconductor device manufacturing process, with the properties close to those before use, and can be widely used for the collection, recycling, reuse, etc. It can be done.

It is a top view of the chemical | medical solution receiving member which is one Embodiment of this invention. It is AA sectional drawing of the chemical | medical solution receiving member shown in FIG. It is the figure which showed the structure of the chemical | medical solution collection | recovery apparatus which is one Embodiment of this invention. It is the figure which showed the structure of the chemical | medical solution collection | recovery apparatus which is other embodiment of this invention. It is the figure which showed the structure of the chemical | medical solution collection | recovery apparatus which is further another embodiment of this invention. It is a sectional side view of the chemical | medical solution receiving member which is other embodiment of this invention. It is the top view which showed the chemical | medical solution receiving cover used for the chemical | medical solution receiving member of FIG. FIG. 7 is a side cross-sectional view when the chemical liquid receiving lid of FIG. 6 is applied to the chemical liquid receiving member of FIG. 1. FIG. 2 is a side sectional view when a sensor is provided on the chemical liquid receiving member of FIG. 1. It is the figure which showed the structure of the reproduction | regeneration cycle using the reproduction | regeneration apparatus of the collect | recovered polishing slurry. It is the figure which showed schematic structure of the conventional chemical | medical solution collection | recovery apparatus used by the comparative example. FIG. 4 is a diagram showing the amount of polishing slurry recovered in Example 2 and Comparative Example 2. It is the figure which showed the collection | recovery amount of the pure water in Example 2 and Comparative Example 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,11 ... Chemical solution receiving member, 2,12 ... Chemical solution inflow port, 3,13 ... Chemical solution storage part, 4,14 ... Chemical solution discharge port, 5 ... Chemical solution receiving lid, 5a ... Opening, 21 ... Chemical solution recovery device, 22 ... Container, 23 ... Chemical solution recovery pump, 24 ... Collection tank, 25 ... Disposal tank, 41 ... Chemical solution collection device, 42 ... Disposal pump

Claims (10)

A chemical liquid inlet into which the chemical liquid flows in, a chemical liquid storage part capable of storing a predetermined amount of the chemical liquid flowing in from the chemical liquid inlet, a chemical liquid outlet for discharging a chemical liquid exceeding a predetermined amount of the chemical liquid storage part, A chemical receiving member having
A chemical recovery pump for aspirating the recovered chemical stored in the chemical storage section;
A recovery tank for storing the recovered chemical liquid aspirated by the chemical liquid recovery pump;
A waste tank for storing a waste chemical liquid discharged from the chemical liquid outlet;
The chemical | medical solution collection | recovery apparatus characterized by having. 2. The chemical recovery apparatus according to claim 1, further comprising a waste pump that sucks the waste chemical stored in the chemical storage. 3. The chemical recovery apparatus according to claim 1 , wherein when two or more types of chemicals are used, the chemical recovery pump and the chemical recovery tank are provided for each type of chemical. The chemical solution recovery apparatus according to any one of claims 1 to 3 , wherein the chemical solution recovery pump and / or the waste pump is a self-contained pump. Measuring means for measuring properties of the chemical liquid flowing into the chemical liquid receiving member;
Control means for determining whether or not to operate the chemical liquid recovery pump based on the measurement result obtained by the measurement means;
5. The chemical solution recovery apparatus according to claim 1 , wherein the chemical solution recovery apparatus is provided. The chemical solution recovery apparatus according to claim 5, wherein the chemical solution is a slurry for semiconductor polishing, and the measuring means is a pH meter, a conductivity meter, a viscometer, a refractometer, or a turbidity meter. A chemical liquid inlet into which the chemical liquid flows in, a chemical liquid storage part capable of storing a predetermined amount of the chemical liquid flowing in from the chemical liquid inlet, a chemical liquid outlet for discharging a chemical liquid exceeding a predetermined amount of the chemical liquid storage part, The used chemical solution is allowed to flow into the chemical solution receiving member having
In the case where the collected chemical liquid that does not contain the cleaning liquid flows into the chemical liquid receiving member, the collected chemical liquid stored in the chemical liquid reservoir is sucked and collected by the chemical liquid recovery pump,
When the waste chemical liquid containing the cleaning liquid flows into the chemical liquid receiving member, the chemical liquid recovery pump stops the suction operation of the chemical liquid recovery pump and recovers the waste chemical liquid from the chemical liquid discharge port. Method. In the case where the recovered chemical liquid and the waste chemical liquid alternately flow into the chemical liquid receiving member, after the inflow of the waste chemical liquid is stopped in the chemical liquid reservoir, The chemical solution recovery method according to claim 7, wherein the waste chemical solution stored in the chemical solution storage part is sucked by a waste pump. The chemical solution recovery method according to claim 7 or 8, wherein the chemical solution is a slurry for semiconductor polishing, and the cleaning solution is ultrapure water. Claim 7, characterized in that said chemical solution receiving pH of the drug solution flowing into the member, conductivity, viscosity, refractive index or turbidity measured, to determine the said waste chemical and the recovery liquid medicine on the basis of the measurement result The chemical | medical solution collection method of any one of thru | or 9 .

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