JPH07326600A - Method and device for chemical treatment - Google Patents

Abstract

PURPOSE:To provide a chemical treatment device which can hold chemicals at a specified concentration range and a chemical processing method which can realize stable treatment effect. CONSTITUTION:The device is provided with a treatment tank 11 for performing chemical treatment for a sample S, a mixing tank 12 for mixing chemical L, a circulation system 13 for circulating chemical L by the mixing tank 12 and the treatment tank 11 and a concentration adjusting system 17 for supplying concentration adjusting liquid L1 to the mixing tank 12. The mixing tank 12 is provided with a liquid amount measuring means 14 for measuring a chemical amount inside the mixing tank 12 and a drain pipe 15 with an opening/closing valve 15a. The liquid amount measuring means 14 and the opening/closing valve 15a are provided with a liquid amount control means 16 for operating the opening/closing valve 15a based on a chemical amount inside the mixed tank 12 measured by the chemical amount measuring means 14. Thereby, concentration adjusting liquid L1 is supplied into the mixing tank 12 held at a specified chemical amount and chemical L is mixed in a specified concentration range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical treatment apparatus and a chemical treatment method, and more particularly to a chemical treatment apparatus and a chemical treatment method used when a sample is treated with a chemical in a semiconductor device manufacturing process.

[0002]

2. Description of the Related Art In a semiconductor device manufacturing process, for example, a chemical treatment apparatus used for cleaning a wafer is constructed as shown in FIG. Sample S in the chemical solution L stored inside
In the processing tank 51 for performing the chemical solution treatment, the mixing tank 52 formed with the partition 51 a provided inside the processing tank 51.
Is provided. The partition 51a is formed lower than the outer peripheral walls of the processing tank 51 and the mixing tank 52 so that the chemical liquid L overflowing in the processing tank 51 flows into the mixing tank 52. A pipe 53 is connected to the processing tank 51 and the mixing tank 52. The pipe 53 is provided with a temperature adjusting means 54, a pump 55 for feeding the chemical liquid L from the preparation tank 52 to the processing tank 51, and a filter 56. Further, the mixing tank 52 is provided with a concentration adjusting system 57 that supplies a predetermined amount of the concentration adjusting liquid L1 to the mixing tank at predetermined time intervals.

The chemical liquid treatment of the sample S using the chemical liquid treatment device 5 is performed as follows. First, the chemical liquid L initially prepared in the mixing tank 52 is poured into the processing tank 51 from the pipe 53, and the chemical liquid L is stored in the processing tank 51 and the mixing tank 52.
Then, while circulating the chemical liquid L between the preparation tank 52 and the treatment tank 51, the sample S is immersed in the chemical liquid L in the treatment tank 51 to perform the chemical treatment of the sample S. At this time, in order to prevent the concentration of the chemical liquid L from decreasing with time, a predetermined amount of the concentration adjusting liquid L1 is supplied into the mixing tank 52 at predetermined time intervals. As the concentration adjusting liquid L1, for example, a stock solution of the chemical liquid L is used.

[0004]

In the above-mentioned chemical liquid processing apparatus, the amount of the chemical liquid in the mixing tank is increased by the concentration adjusting liquid supplied from the concentration adjusting system. However, in the above-mentioned concentration adjusting system, since a predetermined amount of concentration adjusting liquid is supplied irrespective of the amount of the chemical liquid in the mixing tank, the concentration of the chemical liquid in the mixing tank may not fall within the target concentration range. Moreover, the temperature of the chemical liquid in the mixing tank changes because the concentration adjusting liquid is supplied into the mixing tank. For example, with ammonia-hydrogen peroxide water-based chemicals,
When ammonium hydroxide or hydrogen peroxide is supplied as a concentration adjusting liquid into the chemical liquid, the temperature of the chemical liquid rises due to the generation of reaction heat. Here, the amount of concentration decrease over time of the chemical liquid is a value that depends on the chemical liquid temperature. However, in the above concentration adjustment system,
Since a predetermined amount of the concentration adjusting liquid is supplied regardless of the change in the temperature of the chemical liquid in the mixing tank, the concentration of the chemical liquid in the mixing tank may not fall within the target concentration range.

Further, in the above-mentioned chemical solution treatment method, chemical solution treatment of a plurality of samples is repeatedly performed in the chemical solution whose concentration is unstable as described above. Therefore, the processing state of the sample varies.

Therefore, it is an object of the present invention to provide a chemical liquid processing apparatus and a chemical liquid processing method which solve the above problems.

[0007]

[Means for Solving the Problems] A chemical treatment apparatus according to the present invention which achieves the above object, comprises a treatment tank for treating a sample with a chemical,
It is provided with a mixing tank for preparing a chemical solution, a circulation system for circulating the chemical solution between the mixing tank and the processing tank, and a concentration adjusting system for supplying a concentration adjusting liquid to the mixing tank. The mixing tank of the first chemical liquid processing device is provided with liquid amount measuring means for measuring the amount of chemical liquid in the mixing tank and a drain pipe having an opening / closing valve. Further, the liquid amount measuring means and the on-off valve,
Liquid amount control means for operating the on-off valve based on the amount of the liquid medicine in the mixing tank measured by the liquid amount measuring means is connected.

Next, in the mixing tank of the second chemical liquid processing apparatus,
Liquid temperature measuring means for measuring the temperature of the chemical liquid in the preparation tank is provided. Further, in the liquid temperature measuring means and the concentration adjusting system, the concentration for setting the supply amount and the supply time interval of the concentration adjusting liquid based on the drug temperature in the mixing tank measured by the liquid temperature measuring means. Control means are connected. In addition, you may provide the said chemical | medical solution measuring means similar to the said 1st chemical | medical solution processing apparatus, a drain pipe, and a liquid amount control means in the said mixing tank.

The chemical solution treating method of the present invention is such that the initially prepared chemical solution is circulated between the preparation tank and the processing tank, and a predetermined amount of the concentration adjusting solution is supplied to the preparation tank at predetermined intervals. This is a method of treating a sample with a chemical solution in a treatment tank. The first chemical liquid treatment method measures the amount of the chemical liquid in the mixing tank when supplying the concentration adjusting liquid, drains the chemical liquid in the mixing tank based on the amount of the chemical liquid, and drains the chemical liquid in the mixing tank. Keep the amount at a given amount.

In the second chemical liquid treatment method, the temperature of the chemical liquid in the mixing tank is measured when the concentration adjusting liquid is supplied, and the concentration adjusting liquid is supplied into the mixing tank based on the temperature of the chemical liquid. Set quantity and feed time interval. In addition, when supplying the concentration adjusting liquid, it may be performed in the same manner as the first chemical liquid processing method.

[0011]

In the first chemical liquid processing apparatus described above, the amount of chemical liquid in the mixing tank is measured by the liquid amount measuring means. Then, the opening / closing valve of the drain pipe is operated by the chemical liquid amount control means based on the measured chemical liquid amount. Therefore, the chemical liquid in the mixing tank is kept at a predetermined amount.

Further, in the above-mentioned second chemical liquid processing apparatus, the chemical temperature in the mixing tank is measured by the liquid temperature measuring means. Then, based on the measured chemical liquid temperature, the concentration control means sets the supply amount and the supply time interval of the concentration adjusting liquid supplied from the concentration adjusting system. Therefore, the concentration adjusting liquid is supplied into the mixing tank at the supply time interval and the supply amount according to the temperature change of the chemical liquid.

Further, in the above-mentioned first chemical liquid processing method, the chemical liquid is mixed within a predetermined concentration range by supplying the concentration adjusting liquid into the mixing tank in which the amount of the chemical liquid is kept at a predetermined amount.
Therefore, a chemical solution having a predetermined concentration is supplied into the processing tank, and the sample is processed in this chemical solution.

In the second chemical liquid processing method, the supply time interval and the supply amount of the concentration adjusting liquid are set based on the chemical liquid temperature. Therefore, the concentration adjustment liquid is supplied by accurately grasping the amount of concentration change over time of the chemical liquid regardless of the temperature change of the chemical liquid.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the chemical liquid processing apparatus of the present invention will be described below with reference to the block diagram of FIG. The chemical treatment device 1 is
It has a processing tank 11 and a mixing tank 12 adjacent to the processing tank 11. A circulation system 13 is provided between the processing tank 11 and the mixing tank 12.

Further, the mixing tank 12 has a liquid amount measuring means 14
And a drain pipe 15 are provided. A liquid amount control unit 16 is connected to the liquid amount measuring unit 14 and the drain pipe 15. Further, the mixing tank 12 is provided with a concentration adjusting system 17.

The processing tank 11 is a tank in which the chemical solution L is stored and the sample S is processed in the chemical solution L. And the partition 11a between the processing tank 11 and the mixing tank 12 is
It is formed to be lower than the outer peripheral walls of the processing tank 11 and the mixing tank 12, so that the chemical liquid L overflowing the processing tank 11 entirely flows into the mixing tank 12.

The mixing tank 12 is a tank for internally mixing the chemical liquid L. The mixing tank 12 is formed, for example, so that the liquid surface of the chemical liquid L stored therein has a predetermined area at all height positions.

The circulation system 13 includes a processing tank 11 and a mixing tank 1.
It has a pipe 131 for connecting with 2. This piping 13
1 is provided with temperature adjusting means 132 for heating or cooling the chemical liquid L passing through the inside thereof to a predetermined temperature. Also,
The pipe 131 is provided with a pump 133 for pouring the chemical liquid L from the preparation tank 12 toward the treatment tank 11 and a filter 134 for filtering the chemical liquid L in series.

The liquid amount measuring means 14 measures the amount of liquid in the mixing tank 12, and is composed of, for example, a liquid level gauge for measuring the height of the liquid surface.

The drain pipe 15 is connected to, for example, the bottom surface of the mixing tank 12 to open / close the valve 1 for adjusting the amount of chemical liquid to be drained.
5a is provided.

The liquid amount control means 16 receives the signal of the amount of the chemical liquid in the mixing tank 12 measured by the liquid amount measuring means 14, and operates the opening / closing valve 15a of the drain pipe 15 based on the received signal value. It is a thing. The operation of the opening / closing valve 15a by the liquid amount control means 16 is performed so that the inside of the mixing tank 12 is maintained at a predetermined liquid amount.

The above liquid amount measuring means 14 and drain pipe 15
As the opening / closing valve 15a and the liquid amount control means 16, the flow rate control device disclosed in Japanese Patent Application No. 4-82706 may be used.

The concentration adjusting system 17 supplies the concentration adjusting liquid L1 to the blending tank 12, and is composed of a supply pipe 17a, an opening / closing valve 17b and a controller 17c. The control unit 17c is connected to the opening / closing valve 17b and operates the opening / closing valve 17b. In the control unit 17c, the opening / closing valve 17b is operated so that a predetermined amount of the concentration adjusting liquid L1 is supplied to the mixing tank 12 each time a predetermined time has elapsed. The supply time interval and the supply amount of the concentration adjusting liquid L1 are set based on the data of the concentration change of the chemical liquid L over time. Here, for example, a sample S made of a silicon wafer
When the so-called SC-1 cleaning is performed by immersing the product in a chemical solution composed of an ammonia-hydrogen peroxide aqueous solution for cleaning,
Ammonium hydroxide and hydrogen peroxide are used as the concentration adjusting liquid L1. Then, the concentration adjusting system 17 is separately prepared for each concentration adjusting liquid L1. Further, in the case of a treatment other than the above, for example, when a chemical solution of 2 to 4 components is used, the concentration adjusting system 17 is individually prepared for each component.

In the chemical liquid processing apparatus 1 having the above structure, the mixing tank 1
When the chemical liquid L is put into 2 and the pump 133 of the circulation system 13 is operated, the chemical liquid L at a predetermined temperature is fed into the processing tank 11. Then, the chemical liquid L is stored in the processing tank 11, and the chemical liquid treatment of the sample S is performed in the chemical liquid L. Further, since the chemical liquid L overflowing the processing tank 11 flows into the blending tank 12, the chemical liquid L circulates in the processing tank 11 and the supply tank 12. Then, the concentration adjusting liquid L1 is supplied from the concentration adjusting system 17 into the mixing tank 12. On the other hand, the inside of the mixing tank 12 is maintained at a predetermined amount of chemical liquid by the liquid amount control means 16. Therefore, the concentration adjusting liquid L1 is supplied to the mixing tank 12 kept at a predetermined amount of chemical liquid. And the concentration adjusting liquid L
When 1 is supplied, the mixing tank 1
When the increase in the amount of the liquid chemical in 2 is detected, the liquid amount control means 16 operates the opening / closing valve 15a of the drain pipe 15 to keep the amount of the liquid chemical in the mixing tank 12 at a predetermined amount. From the above, the concentration adjusting liquid L1 is always stored in the mixing tank 12 kept at a predetermined chemical amount.
Is supplied, and the chemical liquid is prepared in the preparation tank 12 within a predetermined concentration range.

Next, the chemical liquid treating apparatus of the second embodiment will be explained based on the block diagram of FIG. The same reference numerals as those in FIG. 1 are used for the same components as those in the first embodiment. The chemical liquid processing apparatus 2 has a processing tank 11, a mixing tank 12, a circulation system 13 and a concentration adjusting system 17 similar to those in the first embodiment.
Further, the mixing tank 12 is provided with a liquid temperature measuring means 21. A concentration control means 22 is connected to the liquid temperature measuring means 21.

The liquid temperature measuring means 21 is a means for measuring the temperature of the chemical liquid in the mixing tank 12.

The concentration control means 22 is a concentration control system 17
Is integrally formed with the control unit 17c. The concentration control means 22 stores the amount of change over time in the concentration of the chemical liquid regarding the chemical liquid L to be used, as data for each temperature of the chemical liquid. Further, here, the signal of the chemical liquid temperature in the mixing tank 12 measured by the liquid temperature measuring means 21 is received. And
From the received signal value and the stored data, the amount of change over time in the concentration of the chemical liquid in the mixing tank 12 is predicted, and the mixing tank 1
The supply time interval and the supply amount of the concentration adjusting liquid L1 are set so that the concentration of the chemical liquid in 2 is maintained within a predetermined range. And
The on-off valve 17b is operated based on this set value.

In the chemical liquid processing device 2, the liquid temperature measuring means 2 is used.
1 and the concentration control means 22 provide the chemical liquid L.
Mixing tank 12 with supply time interval and supply amount according to temperature change of
The concentration adjusting liquid L1 is supplied therein. Therefore, regardless of the temperature change of the chemical liquid L, the concentration adjusting liquid L1 is accurately supplied, which accurately grasps the amount of concentration change over time of the chemical liquid L.

Further, FIG. 3 shows a configuration diagram of the chemical liquid processing apparatus 3 of the third embodiment. The chemical treatment device 3 shown here is
The chemical liquid treatment apparatus of the first embodiment is provided with the liquid temperature measuring means 21 and the concentration control means 22 of the second embodiment.

In this chemical liquid processing apparatus 3, the concentration adjusting liquid L1 is supplied by accurately predicting the change over time of the concentration of the chemical liquid L in the mixing tank 12 in which the chemical liquid L is kept at a predetermined chemical amount. The controllability of the chemical concentration in the mixing tank 12 is further improved as compared with the first and second embodiments.

If there is a possibility that the amount of chemical liquid in the mixing tank 12 will increase, the mixing tank 12 is provided with a liquid amount adjusting liquid supply system (not shown here), and the opening / closing valve of this system is provided with the above liquid amount. The control means 16 may be connected. In the chemical liquid processing device having such a structure, the inside of the mixing tank 1 is maintained at a predetermined amount by the drainage of the chemical liquid in the mixing tank 12 or the supply of the liquid amount adjusting liquid into the mixing tank 12.

Next, an example of the chemical treatment method will be described.
Here, as an example, the case where the sample S made of a silicon wafer is cleaned with the chemical liquid L made of the SC-1 using the chemical liquid amount device 3 of the third embodiment shown in FIG. 3 is used.
Will be described with reference to the flowchart of FIG. First, in step S11, ammonium hydroxide, hydrogen peroxide solution, and pure water are supplied into the mixing tank 12 at a ratio of, for example, about 1: 1: 5 to initially prepare the chemical liquid L. Then, the chemical liquid L is poured into the processing tank 11 from the circulation system 13 to store a predetermined amount of the chemical liquid L in the processing tank 11 and the preparation tank 12.

Next, in step S12, the chemical treatment of the sample S in the treatment tank 11 is started. Further, circulation of the chemical liquid L between the processing tank 11 and the mixing tank 12 is started.

Then, in step S13, the liquid temperature measuring means 21 measures the temperature of the chemical liquid in the mixing tank 12.
Then, in step S14, the concentration control means 22 predicts the amount of change over time in the chemical liquid concentration based on the chemical liquid temperature measured above, and supplies the concentration adjusting liquid L1 so that the chemical liquid concentration is maintained within a predetermined range. Set the time interval and the supply amount. Here, in order to control the chemical concentration within a narrow range,
Set the supply time interval as short as possible. On this occasion,
Ammonium hydroxide and hydrogen peroxide solution are used as the concentration adjusting liquid L1, and the supply time interval and the supply amount are individually set for each concentration adjusting liquid L1.

Next, in step S15, it is determined whether the supply time interval set in step S14 has elapsed. At this time, the supply time interval elapses from the time when the chemical liquid L is prepared or the time when the prepared chemical liquid L is expected to reach a predetermined concentration range with the elapse of time. When the set time has elapsed, the next step S
At 16, the concentration adjusting liquid L1 having the supply amount set above is supplied to the mixing tank 12. Then return to step 13 above,
The temperature of the chemical liquid in the mixing tank 12 to which the concentration adjusting liquid L1 is supplied is measured. Next, in step S14, the supply time interval and supply amount of the concentration adjusting liquid L1 are reset as described above based on the measured chemical liquid temperature. Then, in step S15, it is determined whether or not the set time has elapsed from the time when the concentration adjusting liquid L1 was supplied, and the concentration adjusting liquid L1 is supplied to the mixing tank 12 in step S16 as described above. Thereafter, the above steps S13 to S16 are repeated.

On the other hand, in parallel with the above steps S13 to 16, the following steps S23 to 25 are performed. First, in step S12, the chemical liquid treatment of the sample S and the circulation of the chemical liquid L are started, and then, in step S23, the liquid amount measuring means 14 measures the amount of the chemical liquid in the mixing tank 12.

Next, in step S24, it is determined whether or not the amount of chemical liquid measured in step S23 has increased. If it is determined that the number has increased, step S
Proceeding to 25, the chemical liquid L in the mixing tank 12 is drained. Then, the inside of the mixing tank 12 is kept at a predetermined amount of liquid medicine. On the other hand, when it is determined that the number does not increase, the process returns to step S23 and the following steps are repeated.

In the above-mentioned chemical treatment method, the temperature of the chemical in the treatment tank 11 is maintained at a predetermined temperature by the temperature adjusting means 132. On the other hand, in the mixing tank 12, the reaction heat is generated by the supply of the concentration adjusting liquid L1 and the chemical liquid temperature rises. Then, the supply time interval and the supply amount of the concentration adjusting liquid L1 are set based on the increased chemical liquid temperature. Therefore, the concentration adjustment liquid is supplied by accurately grasping the amount of concentration change over time of the chemical liquid regardless of the temperature change of the chemical liquid. At this time, the amount of the chemical liquid in the mixing tank 12 is always kept at a predetermined amount in steps 23 to 25. Therefore, when the concentration adjusting liquid L1 is supplied, the amount of the chemical liquid in the mixing tank 12 is always kept at a predetermined amount. Therefore, in the mixing tank 12, the chemical liquid L
Are mixed in a predetermined concentration range. Then, the chemical liquid L is supplied into the processing tank 11, and the sample S in the chemical liquid L having a predetermined concentration is
Chemical treatment is performed.

In the above embodiment, the adjustment of the liquid amount and the adjustment of the concentration are performed according to independent flowcharts. However, the steps S23 and S24 may be performed before the concentration adjusting liquid is supplied in step S16, and the above adjusting steps may be performed according to a series of flowcharts.

[0041]

As described above, according to the chemical liquid processing apparatus of the present invention, the mixing tank is provided with the liquid amount measuring means, the liquid amount measuring means, the drain pipe, and the liquid amount controlling means. It is possible to keep the amount of the liquid medicine of a predetermined amount. Further, the concentration adjusting system of the mixing tank is provided with the concentration controlling means connected to the liquid temperature measuring means, so that the concentration adjusting liquid is supplied into the mixing tank at the supply time interval and the supply amount according to the change of the chemical liquid temperature. be able to. Therefore, it becomes possible to prepare a chemical solution having a predetermined concentration range in the preparation tank and supply the chemical solution in a stable concentration range to the processing tank. Further, in the chemical liquid processing method of the present invention, the chemical liquid can be mixed in a stable concentration range by supplying the concentration adjusting liquid into the mixing tank in which the chemical liquid amount is kept at a predetermined amount. Further, by setting the supply time interval and the supply amount of the concentration adjusting liquid based on the temperature of the liquid medicine, it is possible to prepare the liquid medicine within a predetermined concentration range regardless of the temperature change of the liquid medicine. Therefore, it is possible to prepare a chemical solution in a stable concentration range in the preparation tank and process the sample in the chemical solution. Therefore, the chemical treatment effect of the sample can be stabilized.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a chemical liquid processing apparatus of a first embodiment.

FIG. 2 is a configuration diagram of a chemical liquid processing apparatus of a second embodiment.

FIG. 3 is a configuration diagram of a chemical liquid processing apparatus of a third embodiment.

FIG. 4 is a flowchart of a chemical treatment method according to an embodiment.

FIG. 5 is a configuration diagram of a conventional chemical liquid processing apparatus.

[Explanation of symbols]

 1, 2 and 3 Chemical liquid treatment device 11 Treatment layer 12 Preparation layer 13 Circulation system 14 Liquid amount measuring means 15 Drain pipe 15a Open / close valve 16 Liquid amount controlling means 17 Concentration adjusting system 21 Liquid temperature measuring means 22 Concentration controlling means S Sample L Chemical liquid L1 concentration adjusting solution

Claims (6)

[Claims] 1. A treatment tank for storing a chemical solution and processing a sample in the chemical solution, a preparation tank for preparing the chemical solution, a preparation tank connected to the preparation tank and the processing tank, and In a chemical solution treatment device comprising a circulation system for circulating the chemical liquid between the inside of the treatment tank and a concentration adjusting system provided in the mixing tank for supplying a concentration adjusting liquid to the mixing tank, the mixing tank includes: A liquid amount measuring unit for measuring the amount of the chemical liquid in the mixing tank and a drain pipe having an opening / closing valve are provided, and the liquid amount measuring unit and the opening / closing valve have the mixing amount measured by the liquid amount measuring unit. A chemical liquid treatment apparatus, to which a liquid volume control means for operating the on-off valve based on the amount of chemical liquid in the tank is connected. 2. A treatment tank for storing a chemical solution and processing a sample in the chemical solution, a preparation tank for preparing the chemical solution, a preparation tank connected to the preparation tank and the processing tank, and In a chemical solution treatment device comprising a circulation system for circulating the chemical liquid between the inside of the treatment tank and a concentration adjusting system provided in the mixing tank for supplying a concentration adjusting liquid to the mixing tank, the mixing tank includes: Liquid temperature measuring means for measuring the temperature of the chemical liquid in the mixing tank is provided, and the liquid temperature measuring means and the concentration adjusting system are based on the chemical temperature in the mixing tank measured by the liquid temperature measuring means. A chemical liquid treatment apparatus, to which a concentration control means for setting a supply amount and a supply time interval of the concentration adjusting liquid by the concentration adjusting system is connected. 3. The chemical liquid processing apparatus according to claim 2, wherein the mixing tank is provided with a liquid amount measuring means for measuring the amount of the chemical liquid in the mixing tank, and a drain pipe having an opening / closing valve. A liquid quantity control means for operating the opening / closing valve based on the amount of the chemical liquid in the mixing tank measured by the liquid quantity measuring means is connected to the quantity measuring means and the opening / closing valve. Chemical processing equipment. 4. The initially prepared chemical liquid is stored in a mixing tank and a processing tank, the chemical liquid is circulated between the mixing tank and the processing tank, and a predetermined amount of a concentration adjusting liquid is supplied to the mixing tank every predetermined time. In the method of treating a sample with a chemical solution in the treatment tank while supplying the solution, when supplying the concentration adjusting liquid, the amount of the chemical solution in the preparation tank is measured, and the inside of the preparation tank based on the amount of the chemical solution is measured. The chemical treatment method, characterized in that the chemical of (4) is drained to maintain the amount of the chemical in the mixing tank at a predetermined amount. 5. The initially prepared chemical liquid is stored in a mixing tank and a processing tank, the chemical liquid is circulated between the mixing tank and the processing tank, and a predetermined amount of a concentration adjusting liquid is supplied to the mixing tank every predetermined time. In the method of treating a sample with a chemical solution in the treatment tank while supplying the solution, when supplying the concentration adjusting solution, the temperature of the chemical solution in the compounding tank is measured, and the concentration adjusting solution is based on the temperature of the solution. And a supply time interval are set. 6. The chemical liquid treatment method according to claim 5, wherein when the concentration adjusting liquid is supplied, the chemical liquid amount in the mixing tank is measured, and the chemical liquid in the mixing tank is determined based on the measured chemical liquid amount. A method for treating a chemical liquid, characterized by draining and maintaining a predetermined amount of the chemical liquid in the mixing tank.