JPH10326765A - Substrate treating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate treating device which can suppress the concentration fluctuation of a treating liquid, caused by the pressure fluctuation of pure water flowing through a pure water supplying pipeline. SOLUTION: A chemical introducing valve 9 introduces a chemical to pure water in a pure water supplying pipeline 2 at the flow rate corresponding to the differential pressure between the pressure of the chemical on the inlet side and that of the pure water on the outlet side. A pure water pressure fluctuation feedback section 60A corrects a chemical flow rate control voltage Vd1 given from a chemical concentration feedback control section 40 so as to fluctuate the pressure of the chemical in accordance with the pressure fluctuation of the pure water in the pipeline 2. The corrected chemical supply control voltage Vd1' is given to a chemical pressure regulator 19 through an electropneumatic converter 20. Therefore, the pressure of the chemical is adjusted in accordance with the pressure fluctuation of the pure water and the differential pressure between the inlet side and the outlet side of the valve 9 is maintained constantly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus for performing a surface treatment on a substrate such as a semiconductor wafer or a glass substrate for a liquid crystal display with a processing liquid, and more particularly, to a substrate processing apparatus obtained by mixing a chemical solution and pure water. The present invention relates to a technique for controlling the concentration of a processing solution.

[0002]

2. Description of the Related Art Conventionally, as a substrate processing apparatus of this type, for example, an apparatus described in Japanese Patent Application Laid-Open No. 7-22369 is known. This apparatus includes a substrate processing tank for performing a surface treatment on a substrate, and a processing liquid supply unit for supplying a processing liquid to the substrate processing tank. The processing liquid supply section is provided with a pure water supply path and a chemical liquid supply path. The pure water supply path is connected between the substrate processing tank and a pure water supply source. One end of the chemical supply path is introduced into the chemical in the chemical tank, and the other end is connected to the pure water supply path via a chemical introduction valve. Pressurized nitrogen gas is introduced into the chemical liquid tank, and the chemical liquid in the chemical liquid tank is pressurized by the gas pressure, whereby the chemical liquid is pressure-fed to the chemical liquid supply path.

The chemical liquid introduction valve has a chemical liquid supply path connected to the inlet side and a pure water supply path connected to the outlet side, and a differential pressure between the chemical liquid pressure on the inlet side and the pure water pressure on the outlet side. Is introduced into the pure water supply path on the outlet side.

A pressure sensor for detecting the pressure of the chemical is attached to the chemical supply path. The detection signal of this pressure sensor is given to a gas pressure control unit that controls the pressure of nitrogen gas introduced into the chemical liquid tank. The gas pressure control unit obtains a deviation between the detection signal and a predetermined reference value, and controls the pressure of the nitrogen gas so as to cancel the deviation. As a result, the chemical pressure in the chemical supply path is maintained constant.
On the other hand, a pure water pressure regulator (pressure control valve) is provided in the pure water supply path. The pressure and flow rate of the pure water flowing through the secondary-side pure water supply path are set to constant values by the pure water pressure regulator.

As described above, the chemical liquid pressure at the inlet side of the chemical liquid introduction valve is controlled to be constant, and the pure water pressure at the outlet side of the chemical liquid introduction valve is set to a constant value, whereby the inlet liquid is controlled. The pressure difference between the chemical pressure on the outlet side and the pure water pressure on the outlet side becomes constant, and the chemical liquid at a flow rate according to the differential pressure is introduced into the pure water, so that a processing liquid having a predetermined concentration can be obtained. I have.

[0006]

However, the prior art having such a structure has the following problems. In order to obtain a heated treatment liquid, heated pure water may be circulated through a pure water supply passage. When the heated pure water flows through the pure water pressure regulator, the pure water pressure regulator is thermally deformed, and the pure water pressure in the secondary-side pure water supply path fluctuates. As a result, the differential pressure between the chemical pressure on the inlet side and the pure water pressure on the outlet side fluctuates even though the chemical pressure on the inlet side of the chemical liquid introduction valve is controlled to be constant. Due to the fluctuation of the differential pressure, there arises a problem that the flow rate of the chemical solution introduced into the pure water fluctuates and the concentration of the processing liquid fluctuates.

[0007] The present invention has been made in view of such circumstances, and a substrate processing apparatus capable of suppressing fluctuations in the concentration of a processing liquid due to fluctuations in the pressure of pure water flowing through a pure water supply path. The main purpose is to provide

[0008]

The present invention has the following configuration in order to achieve the above object. That is, the invention according to claim 1 is a substrate processing apparatus for performing a surface treatment of a substrate with a processing liquid obtained by mixing pure water and a chemical solution, and a substrate processing for performing a surface treatment of the substrate with the processing liquid. Department and
A pure water supply path connected between the substrate processing unit and the pure water supply source, a chemical liquid tank having a sealed structure for storing a chemical liquid, and a chemical liquid supply path having one end introduced into the chemical liquid in the chemical liquid tank. A chemical liquid pressure feeding means for feeding a chemical liquid in the chemical liquid tank to the chemical liquid supply path, and an inlet side at the other end of the chemical liquid supply path,
An outlet side is connected to the pure water supply path, and a chemical liquid introduction valve for introducing a chemical liquid into the pure water supply path at a flow rate corresponding to a differential pressure between the chemical liquid pressure on the inlet side and the pure water pressure on the outlet side, A chemical pressure regulator for adjusting the chemical pressure in the chemical supply path based on the chemical flow rate operation amount set in relation to the concentration target value of the liquid, and a pure water pressure current value in the pure water supply path. When the present pure water pressure current value is higher than a predetermined pure water pressure reference value, the chemical liquid flow rate operation amount is corrected in the direction of increasing the chemical liquid pressure, and the corrected amount is given to the chemical liquid pressure regulator. When the current water pressure value is lower than the pure water pressure reference value, pure water pressure fluctuation feedback means for correcting the chemical liquid flow rate operation amount in the direction of lowering the chemical liquid pressure and giving it to the chemical liquid pressure regulator is provided. It is characterized by that.

According to a second aspect of the present invention, there is provided a substrate processing apparatus for performing a surface treatment of a substrate with a processing liquid obtained by mixing pure water and a chemical solution, wherein the substrate is subjected to a surface processing of the substrate with the processing liquid. A processing unit, a pure water supply path connected between the substrate processing unit and a pure water supply source, a chemical solution tank having a closed structure for storing a chemical solution, one end is introduced into the chemical solution in the chemical solution tank, The other end is set in relation to the chemical supply path connected in the middle of the pure water supply path, the chemical liquid pumping means for sending the chemical in the chemical liquid tank to the chemical supply path, and the target concentration of the processing liquid. By operating the opening of the valve based on the chemical flow rate operation amount, a chemical flow control valve that adjusts the chemical flow in the chemical supply path, and the current pure water pressure value in the pure water supply path,
When this pure water pressure current value becomes higher than a predetermined pure water pressure reference value, the chemical liquid flow rate operation amount is corrected in the direction of increasing the chemical liquid flow rate and given to the chemical liquid flow rate control valve, and the pure water pressure is adjusted. When the present value is lower than the pure water pressure reference value, pure water pressure fluctuation feedback means for correcting the chemical liquid flow rate operation amount in the direction of lowering the chemical liquid flow rate and giving it to the chemical liquid flow rate control valve is provided. It is characterized by.

According to a third aspect of the present invention, in the apparatus according to the first aspect, the pure water pressure fluctuation feedback means measures a pure water pressure present value in the pure water supply path. Pure water pressure fluctuation value calculation means for obtaining a pressure fluctuation value of the pure water pressure current value by comparing the actually measured pure water pressure current value with a predetermined pure water pressure reference value,
A pure water pressure fluctuation value adding means for adding the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and giving it to the chemical liquid pressure regulator.

According to a fourth aspect of the present invention, in the apparatus according to the second aspect, the pure water pressure fluctuation feedback means measures a current pure water pressure value in the pure water supply path. Pure water pressure fluctuation value calculation means for obtaining a pressure fluctuation value of the pure water pressure current value by comparing the actually measured pure water pressure current value with a predetermined pure water pressure reference value,
A pure water pressure fluctuation value adding means for adding the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and giving it to the chemical liquid flow rate control valve.

According to a fifth aspect of the present invention, in the apparatus according to the first aspect, the pure water pressure fluctuation feedback means includes a pure water pressure present value based on a pure water flow present value in the pure water supply passage. Pure water pressure calculating means for calculating the pure water pressure current value, and comparing the calculated pure water pressure current value with a predetermined pure water pressure reference value to obtain a pressure fluctuation value of the pure water pressure current value. The apparatus further includes a water pressure fluctuation value calculating means, and a pure water pressure fluctuation value adding means for adding the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and giving the pure water pressure fluctuation value to the chemical liquid pressure regulator.

According to a sixth aspect of the present invention, in the apparatus according to the second aspect, the pure water pressure fluctuation feedback means includes a pure water pressure present value based on a pure water flow present value in the pure water supply passage. Pure water pressure calculating means for calculating the pure water pressure current value, and comparing the calculated pure water pressure current value with a predetermined pure water pressure reference value to obtain a pressure fluctuation value of the pure water pressure current value. The apparatus includes a water pressure fluctuation value calculating means, and a pure water pressure fluctuation value adding means for adding the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and giving the pure water pressure fluctuation value to the chemical liquid flow rate control valve.

According to a seventh aspect of the present invention, in the apparatus according to the first aspect, the apparatus further comprises a target value of a chemical flow rate of the chemical flowing through the chemical supply path and pure water flowing through the pure water supply path. Target value setting means for setting a target value of the pure water flow rate, and a concentration deviation between the target concentration of the treatment liquid and the current concentration of the treatment liquid are determined and given to the chemical pressure regulator so as to cancel the concentration deviation. A chemical solution concentration feedback control means for adjusting a chemical solution flow rate operation amount, wherein the chemical solution concentration feedback control device is configured to control the processing solution based on the chemical solution flow rate target value and the pure water flow rate target value provided from the target value setting means. Concentration target value calculation means for calculating a concentration target value; concentration deviation calculation means for calculating a concentration deviation between a processing liquid concentration target value given from the concentration target value calculation means and a current concentration of the processing liquid; Cancel density deviation A density control input calculation means for calculating the concentration operation of such processing solution, the concentration operation amount the calculated is intended to include the operation amount conversion means for converting the chemical flow operation amount.

According to an eighth aspect of the present invention, in the apparatus according to the second aspect, the apparatus further includes a chemical solution flow rate target value of the chemical solution flowing through the chemical solution supply path and pure water flowing through the pure water supply path. A target value setting means for setting a target value of the pure water flow rate, a density deviation between the target concentration of the processing liquid and the current concentration of the processing liquid, and giving the chemical liquid flow control valve so as to cancel the concentration deviation. A chemical solution concentration feedback control means for adjusting a chemical solution flow rate operation amount, wherein the chemical solution concentration feedback control device is configured to control the processing solution based on the chemical solution flow rate target value and the pure water flow rate target value provided from the target value setting means. Concentration target value calculation means for calculating a concentration target value; concentration deviation calculation means for calculating a concentration deviation between a processing liquid concentration target value given from the concentration target value calculation means and a current concentration of the processing liquid; Cancel density deviation A density control input calculation means for calculating the concentration operation of such processing solution, the concentration operation amount the calculated is intended to include the operation amount conversion means for converting the chemical flow operation amount.

According to a ninth aspect of the present invention, in the apparatus according to the seventh or eighth aspect, the apparatus further calculates a current concentration of the treatment liquid based on the current value of the chemical flow rate and the current value of the pure water flow rate. The present concentration value of the processing solution is given to the concentration deviation calculating means.

According to a tenth aspect of the present invention, in the apparatus according to the seventh or eighth aspect, the apparatus further comprises a pure water supply path upstream of a position where a chemical is introduced into the pure water supply path. A pure water pressure regulator that is arranged in the pure water flow path and adjusts the pure water pressure in the pure water supply path based on the pure water flow operation amount,
A pure water flow rate target value given from the target value setting means,
A pure water flow rate feedback control means for obtaining a deviation from the pure water flow current value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and giving the pure water flow manipulated variable to the pure water pressure regulator. Is provided.

According to an eleventh aspect of the present invention, in the apparatus according to the tenth aspect, the target value setting means sets a chemical liquid flow target value and a pure water flow target value which change with time. It is.

According to a twelfth aspect of the present invention, in the apparatus according to the eleventh aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. Until the inside of the substrate processing section is replaced with the processing liquid, the initial target values of the chemical liquid flow target value and the pure water flow target value are set higher than the subsequent target values.

According to a thirteenth aspect of the present invention, in the apparatus according to the eleventh aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. Until the inside of the substrate processing unit is replaced with the processing liquid, the initial target value of the chemical liquid flow rate target value,
Thereafter, the target value of the pure water flow rate is set to be constant while the target value is set higher than the target value of the chemical liquid flow rate.

According to a fourteenth aspect of the present invention, in the apparatus according to the first aspect, the apparatus further comprises a target concentration of the treatment liquid and a target pure water flow rate of the pure water flowing through the pure water supply passage. A target value setting means for setting, and a concentration deviation between the concentration target value of the treatment liquid and the current concentration of the treatment liquid are obtained, and a chemical flow rate operation amount given to the chemical liquid pressure regulator is adjusted so as to cancel the concentration deviation. And a concentration deviation calculating means for calculating a concentration deviation between a concentration target value of the treatment liquid given from the target value setting means and a current concentration value of the treatment liquid. Means, a concentration manipulated variable calculating means for calculating a concentration manipulated variable of the processing liquid which cancels out the concentration deviation, and an operation amount converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable.

According to a fifteenth aspect of the present invention, in the apparatus according to the second aspect, the apparatus further comprises a target concentration of the treatment liquid and a target pure water flow rate of the pure water flowing through the pure water supply passage. A target value setting means for setting, a concentration deviation between the target concentration of the treatment liquid and the current concentration of the treatment liquid, and adjusting a chemical liquid flow operation amount given to the chemical liquid flow control valve so as to cancel the concentration deviation. And a concentration deviation calculating means for calculating a concentration deviation between a concentration target value of the treatment liquid given from the target value setting means and a current concentration value of the treatment liquid. Means, a concentration manipulated variable calculating means for calculating a concentration manipulated variable of the processing liquid which cancels out the concentration deviation, and an operation amount converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable.

According to a sixteenth aspect of the present invention, in the device according to the fourteenth or fifteenth aspect, the device further calculates a current concentration value of the processing liquid based on the current value of the chemical solution flow rate and the current value of the pure water flow rate. The present concentration value of the processing solution is given to the concentration deviation calculating means.

According to a seventeenth aspect of the present invention, in the device according to the fourteenth or fifteenth aspect, the device further comprises a pure water supply passage upstream of a position where a chemical solution is introduced into the pure water supply passage. And based on the pure water flow manipulated variable,
A pure water pressure regulator for adjusting the pure water pressure in the pure water supply path; a pure water flow target value provided from the target value setting means; and a deviation between the pure water flow present value and the pure water flow rate. And a pure water flow rate feedback control means for calculating a pure water flow manipulated variable that cancels the deviation, and applying the pure water flow manipulated variable to the pure water pressure regulator.

According to an eighteenth aspect of the present invention, in the apparatus according to the seventeenth aspect, the target value setting means sets a processing solution concentration target value and a pure water flow rate target value, each of which changes with time. Is what you do.

According to a nineteenth aspect of the present invention, in the apparatus according to the eighteenth aspect, the target value setting unit starts supplying a processing liquid into the substrate processing unit filled with pure water. Until the inside of the substrate processing unit is replaced with the processing liquid, while the concentration target value of the processing liquid is set to be constant, as the replacement with the processing liquid progresses,
The pure water flow target value is made smaller than the initial target value.

According to a twentieth aspect of the present invention, there is provided the apparatus according to the first aspect, wherein the apparatus further sets a target value of the concentration of the processing liquid and a target value of the chemical liquid flow rate of the chemical liquid flowing through the chemical liquid supply path. Value setting means for determining a concentration deviation between a target concentration of the processing liquid and a current concentration of the processing liquid, and adjusting a chemical flow rate operation amount applied to the chemical pressure regulator so as to cancel the concentration deviation. Feedback control means, wherein the chemical liquid concentration feedback control means calculates a pure water pure water flow target value based on the treatment liquid concentration target value and the chemical liquid flow target value given from the target value setting means. A pure water flow rate target value calculating means; a concentration deviation calculating means for calculating a concentration deviation between the processing liquid concentration target value given from the target value setting means and the processing liquid concentration current value; Processing solution And the concentration operation amount calculating means for calculating a degree operation amount, a concentration operation amount the calculated is intended to include the operation amount conversion means for converting the chemical flow operation amount.

According to a twenty-first aspect of the present invention, there is provided the apparatus according to the second aspect, wherein the apparatus further sets a target value of the concentration of the treatment liquid and a target value of the chemical flow rate of the chemical to be circulated through the chemical supply path. Value setting means for determining a concentration deviation between the target concentration of the processing liquid and the current concentration of the processing liquid, and adjusting the chemical flow rate operation amount given to the chemical flow control valve so as to cancel the concentration deviation. Feedback control means, wherein the chemical liquid concentration feedback control means calculates a pure water pure water flow target value based on the treatment liquid concentration target value and the chemical liquid flow target value given from the target value setting means. A pure water flow rate target value calculating means; a concentration deviation calculating means for calculating a concentration deviation between the processing liquid concentration target value given from the target value setting means and the processing liquid concentration current value; Processing solution And the concentration operation amount calculating means for calculating a degree operation amount, a concentration operation amount the calculated is intended to include the operation amount conversion means for converting the chemical flow operation amount.

According to a twenty-second aspect of the present invention, in the apparatus according to the twentieth or twenty-first aspect, the apparatus further calculates a current concentration value of the processing solution based on the current value of the chemical solution flow rate and the current value of the pure water flow rate. The present concentration value of the processing solution is given to the concentration deviation calculating means.

According to a twenty-third aspect of the present invention, in the apparatus according to the twentieth or twenty-first aspect, the apparatus further comprises a pure water supply passage upstream of a position where a chemical solution is introduced into the pure water supply passage. And based on the pure water flow manipulated variable,
A pure water pressure regulator for adjusting the pure water pressure in the pure water supply path, a pure water flow target value provided from the pure water flow target value calculation means, and a deviation between the pure water flow present value and A pure water flow control unit that calculates a pure water flow operation amount that cancels the pure water flow deviation and provides the pure water flow operation amount to the pure water pressure regulator.

According to a twenty-fourth aspect of the present invention, in the apparatus according to the twenty-third aspect, the target value setting means sets a processing solution concentration target value and a chemical solution flow rate target value, each of which changes with time. Things.

According to a twenty-fifth aspect of the present invention, in the apparatus according to the twenty-fourth aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. Until the inside of the substrate processing unit is replaced with the processing liquid, the initial target value of the processing liquid concentration target value is set to be larger than the subsequent processing liquid concentration target value, while the chemical liquid flow rate target value is kept constant. To set.

[0033]

The operation of the first aspect of the invention is as follows. The chemical solution pumping means supplies the chemical solution in the chemical solution tank to the inlet side of the chemical solution introduction valve via the chemical solution supply passage. On the other hand, pure water of a constant pressure is supplied to the outlet side of the chemical liquid introduction valve via a pure water supply path. At this time, if the pure water pressure in the pure water supply path increases,
The pure water pressure fluctuation feedback means corrects the chemical liquid flow operation amount in a direction to increase the chemical liquid pressure. The corrected chemical liquid flow operation amount is provided to the chemical liquid pressure regulator. As a result, the chemical pressure regulator increases the pressure of the chemical in the chemical supply path. As a result, the chemical pressure on the inlet side of the chemical introduction valve also increases. In other words, as the pure water pressure on the outlet side of the chemical inlet valve increases, the chemical pressure on the inlet side is increased, and the differential pressure between the pure water pressure on the outlet side of the chemical inlet valve and the chemical pressure on the inlet side is increased. Is kept constant. Conversely, when the pure water pressure in the pure water supply path becomes low, the pure water pressure fluctuation feedback means corrects the chemical liquid flow operation amount in a direction to lower the chemical liquid pressure. As a result, the chemical liquid pressure on the inlet side of the chemical liquid introduction valve decreases, and the differential pressure between the pure water pressure on the outlet side of the chemical liquid introduction valve and the chemical liquid pressure on the inlet side is kept constant. Thus, even if the pure water pressure in the pure water supply path fluctuates, the pressure difference between the inlet side and the outlet side of the chemical liquid introduction valve is always constant, so the pure water in the pure water supply path is always constant. A quantity of drug solution is introduced.

The operation of the invention described in claim 2 is as follows. In the invention of claim 1, the chemical solution pressure is controlled in accordance with the fluctuation of the pure water pressure in the pure water supply passage. However, in the invention of claim 2, the chemical solution flow rate of the chemical solution supply passage is directly controlled. That is, when the pressure of the pure water in the pure water supply path increases, the flow rate of the chemical solution introduced into the pure water decreases. Therefore, the pure water pressure fluctuation feedback unit corrects the manipulated flow rate of the chemical solution in the direction of increasing the flow rate of the chemical solution.
The corrected chemical liquid flow operation amount is given to the chemical liquid flow control valve. As a result, the opening of the chemical liquid flow control valve increases, and the chemical liquid flow rate increases. Conversely, when the pressure of the pure water in the pure water supply path decreases, the flow rate of the chemical solution introduced into the pure water increases. Therefore, the pure water pressure fluctuation feedback unit corrects the chemical flow rate operation amount in a direction to decrease the chemical flow rate. . As a result, the opening degree of the chemical liquid flow rate control valve decreases, and the chemical liquid flow rate decreases. As described above, the chemical liquid flow rate is directly controlled so as to suppress the fluctuation of the chemical liquid flow rate caused by the fluctuation of the pure water pressure in the pure water supply path. A certain amount of chemical solution is always introduced.

According to the third and fourth aspects of the present invention, the pure water pressure detecting means measures the present value of the pure water pressure in the pure water supply path. The pure water pressure fluctuation value calculation means obtains the pressure fluctuation value of the pure water pressure current value by comparing the actually measured pure water pressure current value with the pure water pressure reference value. The pure water pressure fluctuation value adding means corrects the chemical liquid flow operation amount by adding the pure water pressure fluctuation value to the chemical liquid flow operation amount. The corrected amount of the chemical liquid flow rate is supplied to the chemical liquid pressure regulator in the case of the third aspect of the invention, and is supplied to the chemical liquid flow rate regulating valve in the case of the fourth aspect of the invention.

According to the fifth and sixth aspects of the present invention, the pure water pressure calculating means calculates the pure water pressure current value based on the pure water flow present value in the pure water supply path by calculation.
Hereinafter, similarly to the third and fourth aspects of the present invention, the pure water pressure fluctuation value calculating means obtains the pressure fluctuation value of the current pure water pressure value, and the pure water pressure fluctuation value adding means corrects the chemical liquid flow rate operation amount. .

The operation of the invention described in claim 7 is as follows. According to the first aspect of the present invention, the pressure fluctuation of the pure water in the pure water supply path is detected, and the operation amount of the chemical liquid flow rate is corrected based on the fluctuation value of the pure water pressure. The differential pressure between the pressure and the outlet pressure is controlled to be constant. By the way, when the heated chemical solution or pure water flows through the chemical solution introduction valve, the chemical solution introduction valve undergoes thermal deformation, so that even if the pressure difference between the inlet side pressure and the outlet side pressure of the chemical solution introduction valve is controlled to be constant. In some cases, the amount of the chemical solution introduced into pure water changes, and the concentration of the processing solution deviates from the target value. The invention according to claim 7 is provided with target value setting means and chemical solution concentration feedback control means in order to solve such a problem.

More specifically, the target concentration calculating unit calculates the target concentration of the processing liquid based on the chemical flow target and the pure water target given by the target setting unit. The density deviation calculating means obtains a density deviation between the calculated target concentration of the processing liquid and the current concentration of the processing liquid. The concentration manipulated variable calculating means calculates the concentration manipulated variable of the processing liquid which cancels this concentration deviation. The operation amount conversion means converts the calculated concentration operation amount into a chemical liquid flow amount operation amount. The chemical pressure adjuster adjusts the chemical pressure in the chemical supply path based on the chemical flow rate operation amount.

As described above, according to the seventh aspect of the present invention,
The chemical liquid concentration feedback control means adjusts and sets the chemical liquid flow operation amount so as to keep the concentration of the processing liquid constant, and the pure water pressure fluctuation feedback means responds to the fluctuation of the pure water pressure in the pure water supply path. Thus, the concentration change of the processing liquid is effectively suppressed by correcting the set chemical liquid flow rate operation amount and maintaining the differential pressure between the inlet pressure and the outlet pressure of the chemical liquid introduction valve constant. .

The operation of the eighth invention is basically the same as that of the seventh invention. However, the invention of claim 8 is intended to solve the problem caused by the thermal deformation of the chemical liquid flow control valve provided in the chemical liquid supply passage instead of the chemical liquid introduction valve and the like. That is, when the chemical liquid flow rate control valve undergoes thermal deformation, its flow characteristic changes, so that the chemical liquid flow rate varies even with the same valve opening. In view of this, the invention of claim 8 includes the same target value setting means and chemical solution concentration feedback control means as described in the invention of claim 7, and controls the concentration manipulated variable of the processing liquid so as to cancel the concentration deviation of the processing liquid. Calculated, this concentration manipulated variable is converted into the chemical fluid flow manipulated variable and given to the chemical fluid flow control valve.

According to a ninth aspect of the present invention, in the apparatus according to the seventh or eighth aspect, the current concentration value calculating means determines the current concentration of the treatment liquid based on the current value of the chemical solution flow rate and the current value of the pure water flow rate. The value is calculated. The deviation between the target concentration value of the processing liquid and the current concentration value of the processing liquid is obtained by giving the calculated current concentration value of the processing liquid to the concentration deviation calculating means.

The operation of the invention described in claim 10 is as follows. Generally, a pure water pressure regulator is provided in the pure water supply path. This pure water pressure regulator works to keep the secondary pressure constant even if the pressure of the primary pure water supply source fluctuates. When the secondary pressure of the pure water pressure regulator is kept constant, the pure water flow rate becomes constant unless the flow path resistance of the pure water supply path connected to the secondary side of the pure water pressure regulator changes. . However, the flow path resistance of the pure water supply path is not always constant. For example, when processing a substrate with a processing liquid at room temperature, pure water at room temperature flows through the pure water supply path, and when processing with a heated processing liquid, heated pure water flows. There is a difference in the thermal deformation of the pure water supply path between the case where pure water at normal temperature flows and the case where heated pure water flows. In other words, the flow resistance of the pure water supply path varies depending on the temperature of the pure water flowing through. As a result, even if the pure water pressure in the pure water supply path is kept constant, the flow resistance of the pure water supply path changes, so that the flow rate of the pure water fluctuates. Fluctuations in the flow rate of pure water cause fluctuations in the concentration of the processing solution.

The invention according to claim 10 is provided with a pure water flow rate feedback control means in order to solve such a problem. Specifically, the pure water flow rate feedback control means finds a deviation between the pure water flow target value provided from the target value setting means and the pure water flow present value, and deactivates the pure water flow deviation such that the pure water flow deviation is canceled out. Calculate the operation amount. By giving this pure water flow operation amount to the pure water pressure regulator, the pure water pressure in the pure water supply path is adjusted to maintain the pure water flow rate constant.

The operation of the invention described in claim 11 is as follows. The target value setting means sets the target value of the chemical flow rate of the chemical solution and the target value of the pure water flow rate by changing over time, thereby efficiently replacing the processing liquid in the substrate processing unit. The degree of freedom of control can be increased.

The operation of the twelfth aspect is as follows. When the target value of the chemical flow rate of the chemical and the target value of the pure water flow rate of the pure water are set to constant values over time, specifically, the following problems occur. When a certain processing liquid is supplied to the substrate processing unit to perform the surface treatment of the substrate, and then the processing is performed with another processing liquid, first, pure water is supplied to the substrate processing unit, and the used water in the substrate processing unit is used. The treatment liquid is once replaced with pure water. Subsequently, a new processing liquid obtained by mixing pure water and a chemical solution is supplied, and the pure water in the substrate processing unit is replaced with the processing liquid. At this time, if the target value of the flow rate of the chemical solution and the target value of the pure water flow rate are small, the flow rate of the pure water supplied to the substrate processing unit for replacement,
Alternatively, the flow rate of the processing liquid decreases, and the time until the inside of the substrate processing unit is completely replaced with a new processing liquid becomes longer, thereby reducing the processing efficiency. Conversely, setting the flow rate target value of the chemical solution or pure water to a large constant value is not preferable in terms of control accuracy.

In order to solve the above problems, the invention according to claim 12 is characterized in that in the initial stage of replacing the processing liquid in the substrate processing unit, the target value of the chemical flow rate of the chemical and the target value of the chemical flow rate of the pure water are set. Both are set large, and at the stage where the replacement of the processing liquid has progressed to some extent, each flow rate target value is reduced.

The operation of the invention according to claim 13 is as follows. If the target value of the flow rate of the chemical solution and the target value of the pure water flow rate are set to constant values over time, another problem as described below is expected. In the initial stage of replacement, in which the supply of a processing solution obtained by mixing a chemical solution and pure water into the substrate processing unit filled with pure water is started, the inside of the substrate processing unit is filled with pure water. In addition, it takes a long time to reach a desired concentration of the processing liquid in the substrate processing unit, and as a result, processing efficiency is reduced.

In order to solve such a problem, the invention according to claim 13 is to increase the ratio of the chemical flow rate to the pure water flow rate in the initial stage of the replacement when the supply of the processing liquid is started, and By supplying a processing liquid having a high concentration into the substrate processing unit, the rise of the average concentration of the processing liquid in the substrate processing unit is accelerated. Then, at the stage when the average concentration of the processing liquid in the substrate processing unit has increased to some extent, the flow rate of the chemical liquid is reduced,
A processing solution having a predetermined concentration is supplied to the substrate processing unit.

The operation of the invention according to claim 14 and claim 15 is as follows. The invention described in claim 14 has the same purpose as that described in the operation of the invention described in claim 7, and the invention described in claim 15 has been described in the operation of the invention described in claim 8. For the same purpose as described above, a target value setting means and a chemical solution concentration feedback control means are provided.
However, in the inventions according to Claims 14 and 15,
The target value setting means sets a target concentration of the treatment liquid and a target value of the pure water flow rate of the pure water. The concentration deviation calculating means calculates a concentration deviation between the set processing solution concentration target value and the processing solution concentration present value. The other operations are the same as those of the seventh and eighth aspects, and the description is omitted here.

The operation of the invention described in claim 16 is the same as that of the invention described in claim 9, and the description is omitted here.

In the seventeenth aspect of the present invention, the purpose of providing the pure water pressure regulator and the pure water flow rate feedback control means, and the operation thereof are the same as those of the tenth aspect, so that the description here will be made. Is omitted.

The operation of the eighteenth invention is as follows. The target value setting means sets the target value of the concentration of the processing solution and the target value of the pure water flow rate by changing over time to supply the processing solution necessary for replacing the processing solution in the substrate processing unit. The degree of freedom of control of the substrate processing apparatus can be increased, for example, by minimizing the amount.

The operation of the invention described in claim 19 is as follows. When the target concentration of the treatment liquid and the target value of the pure water flow rate of the pure water are made constant over time, the following problems are specifically expected.

If the pure water flow rate target is constant over time,
As long as the concentration target value is constant, the chemical solution flow rate is constant. As a result, a constant flow rate of the processing liquid is always supplied to the substrate processing unit. By supplying the processing liquid at a constant flow rate to the substrate processing unit filled with pure water, the average concentration of the processing liquid in the substrate processing unit gradually increases. As the average concentration of the processing liquid in the substrate processing unit approaches the desired concentration, the curve of the increase in the average concentration of the processing liquid in the substrate processing unit becomes gentler. The processing liquid is continuously supplied to the substrate processing unit until the average concentration of the processing liquid in the substrate processing unit reaches the target concentration. During that time, excess processing liquid in the substrate processing section overflows and is discharged. That is, after the average concentration of the processing liquid in the substrate processing unit has increased to some extent, a constant amount of the processing liquid is supplied to the substrate processing unit even though the average concentration of the processing liquid in the substrate processing unit does not increase so much. Subsequently, since excess processing liquid is discharged, it can be said that the use efficiency of the processing liquid required for replacement is low.

In order to solve such a problem, the invention according to claim 19 is characterized in that the concentration target value is kept constant over time, while the average concentration of the processing liquid in the substrate processing section is set to the concentration target value. , The target value of the pure water flow rate is reduced. Then, the flow rate of the chemical liquid is inevitably reduced, and the flow rate of the processing liquid supplied to the substrate processing unit is reduced, so that it is possible to prevent the processing liquid from being wastefully discharged.

The operation of the invention according to the twentieth and twenty-first aspects is as follows. The invention described in claim 20 has the same purpose as that described in the operation of the invention described in claim 7, and the invention described in claim 21 has been described in the operation of the invention described in claim 8. For the same purpose as described above, a target value setting means and a chemical solution concentration feedback control means are provided.
However, in the inventions according to the twentieth and twenty-first aspects, the target value setting means sets the target concentration of the processing liquid and the target value of the chemical flow rate of the chemical. The pure water flow rate target value calculation means is based on the set processing solution concentration target value and the chemical solution flow rate target value,
Calculate the pure water flow rate target value of pure water. The concentration deviation calculating means calculates a concentration deviation between the set processing solution concentration target value and the processing solution concentration present value. Other operations are the same as those of the seventh and eighth aspects of the present invention, and a description thereof will not be repeated.

The operation of the invention described in claim 22 is the same as that of the invention described in claim 9, and the description is omitted here.

According to the twenty-third aspect of the present invention, the purpose of providing the pure water pressure regulator and the pure water flow rate feedback control means and the operation thereof are the same as those of the tenth aspect. However, the pure water flow rate feedback control means uses the pure water flow rate target value calculated by the pure water flow rate target value calculation means in the process of obtaining the pure water flow rate deviation.

The operation of the invention according to claim 24 is as follows. The target value setting means sets the target concentration of the processing liquid and the target value of the chemical flow rate of the chemical by changing over time to set the target concentration of the processing liquid in the initial stage of replacing the inside of the substrate processing unit with the processing liquid. The degree of freedom of control of the substrate processing apparatus can be increased, for example, by shortening the processing liquid replacement time by increasing the processing liquid.

The operation of the invention according to claim 25 is as follows. If the target value of the concentration of the processing liquid and the target value of the chemical liquid flow rate of the chemical liquid are set to constant values over time, the same disadvantages as described in the operation of the thirteenth invention are expected. That is, when the target concentration of the processing liquid and the target value of the chemical liquid flow rate of the chemical liquid are set to constant values over time, the flow rate of the pure water inevitably becomes constant over time. It takes a long time to reach the concentration. In order to solve such a problem, in the invention according to claim 25, the chemical liquid flow rate target value is set to be constant over time, while the concentration target value is set to be high in the initial stage of replacement when the supply of the processing liquid is started. I do. As a result, the processing solution having a high concentration is supplied into the substrate processing unit in the initial stage of the replacement, so that the average concentration of the processing solution in the substrate processing unit rises quickly. When the average concentration of the processing liquid in the substrate processing unit has increased to some extent, the target concentration of the processing liquid is returned to a desired target value.

[0061]

Embodiments of the present invention will be described below with reference to the drawings. A: First Embodiment A1: Configuration of First Embodiment Apparatus A schematic configuration of a substrate processing apparatus according to the present embodiment will be described with reference to FIG. This substrate processing apparatus performs a surface treatment of a substrate W such as a semiconductor wafer with a processing liquid obtained by mixing pure water and a chemical solution. This substrate processing apparatus is roughly divided into a substrate processing tank 1 that is a substrate processing unit that stores a processing liquid and performs a surface treatment of the substrate W, and a processing liquid supply system that supplies the processing liquid to the substrate processing tank 1. And a control system for controlling the processing liquid supply system.

The substrate processing tank 1 is configured to receive the supply of the processing liquid from the bottom of the tank, and to overflow and discharge the excess processing liquid. Usually, this type of substrate processing apparatus includes a plurality of substrate processing tanks 1 and each of the substrate processing tanks 1 is configured to be supplied with a processing liquid by an individual processing liquid supply system. However, for simplicity of description, a substrate processing apparatus having a single substrate processing tank 1 will be described as an example, but the present invention is not limited to a substrate processing apparatus having a plurality of substrate processing tanks 1. It can also be applied to devices. Further, the present invention is not applied to a substrate processing tank, but can be applied to a substrate processing apparatus having a processing unit for processing substrates one by one.

A2: Configuration of the processing liquid supply system (particularly, pure water supply system) The processing liquid supply system is composed of a pure water supply system and a chemical liquid supply system. First, the pure water supply system will be described.
The substrate processing tank 1 and a pure water supply source are connected by a pure water supply path 2. The pure water supply path 2 is provided with a pure water pressure regulator 3, a pure water flow sensor 4, and a chemical solution mixing section 5 in this order from the pure water supply source side. The pure water pressure regulator 3 is provided with an air pressure (hereinafter referred to as a pilot pressure) given from the electropneumatic converter 6.
Is a control valve that adjusts the pure water pressure on the secondary side of the pure water pressure regulator 3 according to.

More specifically, the pure water pressure regulator 3 has a valve body interlocked with the diaphragm therein. Pilot pressure acts on one surface of the diaphragm, and pure water pressure on the secondary side acts on the other surface. If there is a pressure difference between the two pressures, the diaphragm is deformed and the opening of the valve body changes. When both pressures are balanced, the valve body stops. That is, the valve element is displaced such that the pure water pressure on the secondary side of the pure water pressure regulator 3 is balanced with the pilot pressure. Therefore, by providing a constant pilot pressure, the pure water pressure on the secondary side of the pure water pressure regulator 3 can be made constant. As a result, the flow rate of pure water flowing through the pure water supply path 2 can be kept constant as long as the flow path resistance of the pure water supply path 2 on the secondary side of the pure water pressure regulator 3 does not change.

The electropneumatic converter 6 converts the supplied pressurized air (pressurized air) into an air pressure (pilot pressure) corresponding to an operation voltage from a control system described later and outputs the same. The pure water flow sensor 4 detects the flow of pure water flowing through the pure water supply path 2.
The pure water flow detection signal (current pure water flow value b2) is provided to a control system described later. Further, the pure water supply path 2 is provided with a pure water pressure sensor 7 for detecting the pressure of pure water flowing therethrough. The pure water pressure detection signal (current pure water pressure value e2) is given to a control system described later.

The chemical mixing section 5 has a pure water supply valve 8 for opening and closing the pure water supply path 2 and a plurality of chemical liquid introduction valves for individually introducing different kinds of chemicals into the pure water of the pure water supply path 2. 9 and a liquid supply path 1 connected to the outlet side of each liquid introduction valve 9.
And a chemical supply valve 10 that opens and closes the valve 1.

FIG. 2 shows the structure of the chemical liquid introduction valve, which also has the function of the chemical liquid supply valve 10. Chemical introduction valve 9
As shown in FIG. 2, is connected to an introduction valve connection pipe 12 provided in the middle of the pure water supply path 2. A valve chamber 9a is formed by combining the bottom surface of the chemical solution introduction valve 9 and a bottomed hole drilled in the introduction valve connecting pipe 12. The valve chamber 9a is connected to the chemical solution supply path 11 through a connection hole 9b. The valve chamber 9a is connected to a pure water flow path 12a of the introduction valve connecting pipe 12 through a chemical solution introduction port 9g. In the valve chamber 9a,
A throttle valve 9c for opening and closing the chemical solution inlet 9g and adjusting the opening degree is provided. The base end of the throttle valve 9c is connected and supported by a support 9e that slides and displaces inside the valve body 9d. The support 9e is pressed downward by a spring 9h. In a state where air is not supplied to the pilot air supply port 9i, the support pair 9e and the throttle valve 9c are pressed downward by the spring force of the spring 9h, and at this time, the chemical liquid introduction port 9g is closed. In a state where air is supplied to the pilot air supply port 9i, the support 9e and the throttle valve 9c rise by virtue of the spring force of the spring 9h, and come into contact with the tip of the adjusting bolt 9f screwed into the valve body 9d. Stop. In this state, the liquid inlet 9g is open. By manually adjusting the screwing amount of the adjusting bolt 9f, the throttle valve 9c and the adjusting bolt 9f are brought into contact with each other, and the degree of opening of the chemical solution inlet 9g is adjusted. According to the chemical liquid introduction valve 9, the pressure of the pure water flowing through the pure water flow path 12a on the outlet side is increased by the pressure of the chemical liquid supply path 1 on the inlet side.
By setting each pressure to be lower than the pressure of the chemical solution flowing through 1, the chemical solution having a flow rate corresponding to the differential pressure between the chemical solution pressure on the inlet side and the pure water pressure on the outlet side flows through the pure water flow path 12a. Introduced into pure water.

A3: Configuration of Processing Liquid Supply System (Especially, Chemical Liquid Supply System) The number of chemical liquid supply systems is provided in accordance with the type of processing liquid used in the present apparatus. It is connected to each chemical solution introduction valve 9. Since each chemical solution supply system has the same configuration, one chemical solution supply system illustrated in FIG. 1 will be described below.

One end of the chemical supply path 11 is introduced into the chemical in the chemical tank 13. The chemical tank 13 is pressure-resistant,
And it has a closed structure. A gas supply path 14 is introduced into an upper space in the chemical liquid tank 13. A pressurized inert gas (here, nitrogen gas) is introduced into the chemical liquid tank 13 through the gas supply path 14. The gas supply path 14 is provided with a gas pressure regulator 15 for adjusting the gas pressure on the secondary side. The gas pressure adjuster 15 adjusts the gas pressure on the secondary side according to the pilot pressure given from the electropneumatic converter 16. The electropneumatic converter 16 is provided with a gas pressure setting voltage for setting the pressure of the nitrogen gas in the chemical liquid tank 13 to a constant value. With the above configuration, the nitrogen gas of a constant pressure corresponding to the gas pressure set voltage is introduced into the chemical tank 13 so that the chemical tank 13
The liquid medicine in the inside is pressurized, and the liquid medicine at a constant pressure is supplied to the liquid supply path 11.
To be pumped. The above-described gas supply path 14, gas pressure regulator 15, and electropneumatic converter 16 correspond to a chemical solution pumping unit in the present invention.

The filter 1 for removing particles in the chemical solution is sequentially provided from the chemical solution tank 13 side to the chemical solution supply path 11.
7. A chemical liquid flow sensor 18 for detecting a chemical liquid flow rate, and a chemical liquid pressure regulator 19 for adjusting the chemical liquid pressure on the secondary side are provided. The secondary side of this chemical liquid pressure regulator 19 is connected to the above-mentioned chemical liquid introduction valve 9. The chemical liquid flow rate detection signal (current chemical liquid flow value b1) of the chemical liquid flow sensor 18 is given to a control system described later. The chemical liquid pressure regulator 19 is a control valve having a configuration similar to that of the above-described pure water pressure regulator 3, and adjusts the secondary-side chemical liquid pressure according to the pilot pressure given from the electropneumatic converter 20. I do. The electropneumatic converter 20 outputs a pilot pressure according to an operation voltage from a control system described later.

A4: Schematic Configuration of Control System The control system is composed of computer equipment. This control system is functionally distinguished from the target value setting unit 30.
A, chemical solution concentration feedback control unit 40A, current concentration value calculation unit 5
0, a pure water pressure fluctuation feedback section 60A, and a pure water flow rate feedback control section 70. FIG. 3 is a block diagram showing only the control system of the present embodiment. Hereinafter, FIG.
The description will be made with reference to FIG.

The target value setting section 30A is for setting a target value of the control amount. In the case of a substrate processing apparatus, the goal is to finally bring the concentration of the processing solution to a desired concentration. Since this processing liquid is generated by mixing pure water and a chemical liquid, when the pure water flow rate and the chemical liquid flow rate are determined, the concentration of the processing liquid is uniquely determined. Therefore, it is not always necessary to select the concentration of the processing liquid as the control amount. That is, any two of the processing solution concentration, the chemical solution flow rate, and the pure water flow rate may be set as the control amount. What to select as the control amount is determined by the item to be managed. In the present embodiment, a chemical solution flow rate and a pure water flow rate are used as control amounts. The target value setting unit 30A sets each target value of the chemical liquid flow rate and the pure water flow rate as the control amounts.

Further, the target value setting section 30A sets a chemical liquid flow rate target value and a pure water flow rate target value which change with time. Since the concentration of the processing liquid used for the substrate processing is a constant value, in that sense, it is conceivable to make the target value of the control amount constant over time. However, when the replacement of the processing liquid in the substrate processing tank 1 is efficiently performed or the processing liquid required for the replacement is reduced, it is preferable to change the target value with time, as will be apparent from the description below. .

As shown in FIG. 3, the target value setting section 30A
Is composed of a variable designation unit 31 and a target value output unit 32. The variable specifying unit 31 is for specifying the type of the target value to be set and for specifying the variable for determining the change pattern of the specified target value. The target value output unit 32 outputs a target value that changes with the passage of time, here, a chemical liquid flow target value and a pure water flow target value, based on a variable specified via the variable specifying unit 31.

The chemical concentration feedback control section 40A has a processing liquid concentration target value a3 uniquely determined from the chemical liquid flow target value a1 and the pure water flow target value a2 set by the target value setting section 30A.
Further, a concentration deviation c3 between the target concentration value a3 and the present concentration value b3 of the processing liquid is determined, and the chemical liquid flow rate operation amount d1 is adjusted so as to cancel the concentration deviation c3. The chemical liquid flow rate operation amount d1 is converted into a chemical liquid flow rate operation voltage Vd1 and provided to the pure water pressure fluctuation feedback unit 60A.

The current concentration value calculation section 50 calculates the current concentration value of the processing liquid from the current pure water flow value b2 detected by the pure water flow sensor 4 and the current chemical solution flow value b1 detected by the chemical solution flow sensor 18. b3 is calculated. The current concentration value b3 is provided to the chemical concentration feedback control unit 40A.

[0077] Pure water pressure fluctuation feedback section 60A, when pure water pressure current value e2 detected by the pure water pressure sensor 7, is higher than the pure water pressure reference value P _0, which is determined in advance, chemical pressure Is corrected in a direction to increase the pressure, and conversely, when the present pure water pressure value e2 becomes lower than the pure water pressure reference value P ₀ , the chemical flow operation voltage Vd1 is decreased in the direction to lower the chemical pressure. Vd1 is corrected. The thus-corrected chemical flow rate operation voltage Vd1 ′ is supplied to the electropneumatic converter 20.

The pure water flow rate feedback control unit 70 calculates a deviation c2 between the pure water flow rate target value a2 set by the target value setting unit 30A and the pure water flow rate current value b2 detected by the pure water flow rate sensor 4. Then, a pure water flow operation amount d2 that cancels out the pure water flow deviation c2 is calculated. The pure water flow rate operation amount d2 is converted into a pure water flow rate operation voltage Vd2, and provided to the electropneumatic converter 6.

A5: Operation of Example Apparatus (1) Setting of Target Value First, the operator operates the variable specifying section 31 to determine the type of target value (in this embodiment, the target value of the chemical flow rate a1 and the target of the pure water flow rate). A value a2) is specified, and a variable for determining a change pattern of these target values is specified. Based on these designations, the target value output unit 32 outputs a chemical solution flow target value a1 and a pure water flow target value a2 that change over time.

The above-mentioned target value is set for each processing solution when the substrate is processed using a plurality of types of processing solutions in order. When the supply of the processing liquid to the substrate processing tank 1 is started, the substrate processing tank 1 is filled with pure water. The same applies to the case where a substrate is processed using a certain processing liquid and then the substrate is processed using the next processing liquid. That is, when the processing of the substrate is finished using a certain processing liquid, only the pure water is supplied to the substrate processing tank 1, and the used processing liquid in the substrate processing tank 1 is once replaced with pure water. Subsequently, in a state where pure water is supplied to the substrate processing tank 1, by starting introduction of a chemical solution into the pure water, a new processing liquid is supplied to the substrate processing tank 1,
The pure water in the substrate processing tank 1 is replaced with a new processing liquid. Hereinafter, a state in which pure water is continuously supplied and the substrate processing tank 1 is filled with pure water is referred to as an initial state of replacement, and from this state, a chemical solution is introduced into pure water in the pure water supply path 2. The time is
The description will be made on the assumption that the supply of the processing liquid to the substrate processing tank 1 is started.

(2) Operation of Chemical Solution Concentration Feedback Control Unit 40A Based on the chemical solution flow target value a1 and the pure water flow target value a2, the target concentration value calculation unit 41 calculates the target concentration a3 of the treatment liquid. Specifically, the target concentration a3 of the processing liquid is calculated by the following equation (1). a3 = (a1 × C ₀ ) / (1000 × a2 + a1) (1) where a1 is the target value of chemical liquid flow [cc / min] a2 is the target value of pure water flow [liter / min] a3 is processing Solution concentration target value [%] C ₀ is the concentration of drug substance solution [%]

The calculated target concentration a3 of the processing liquid is given to the subtractor 42 and the adder 45. On the other hand, the current concentration value calculation section 50 calculates the current concentration value b3 of the treatment liquid from the current chemical solution flow value b1 given from the chemical solution flow sensor 18 and the pure water flow current value b2 given from the pure water flow sensor 4. Is calculated by the following equation (2). The calculated current concentration b3 of the processing liquid is supplied to the subtractor 42. b3 = b1 × C ₀ / (1000 × b2 + b1) (2) where b1 is the current value of the chemical flow rate [cc / min] b2 is the current value of the pure water flow rate [liter / min] b3 is the Concentration current value [%] C ₀ is the concentration of drug substance solution [%]

The subtracter 42 subtracts the current concentration b3 of the processing liquid from the target concentration a3 of the processing liquid calculated by the target concentration calculating section 41 to obtain a concentration deviation c3 of the processing liquid.
Ask for. This density deviation c3 is given to the PII ² D calculation unit 43.

The PII ² D calculation section 43 performs a proportional operation (P operation) for determining the concentration manipulated variable in proportion to the concentration deviation c3 of the processing liquid given from the subtractor 42, and a proportional operation to the integration of the concentration deviation c3. Operation (I operation) to determine the concentration manipulated variable by
When, the double integration operation to determine the concentration operation amount in proportion to the double integral of the density deviation c3 (I ² operation), the differential operation of determining the concentration operation amount is proportional to the derivative of the density deviation c3 (D operation) Is calculated according to the control law including the above. This manipulated variable for density control is provided to an adder 45 via a switch 44.

The adder 45 adds the concentration control operation amount of the processing liquid supplied from the PII ² D calculation unit 43 through the switch 44 to the concentration target value a3 of the processing liquid supplied from the concentration target value calculation unit 41. to add. The concentration manipulated variable d3 of the processing liquid obtained by adding the concentration target value a3 and the concentration control manipulated variable is given to the concentration-flow rate converter 46.

The switch 44 is connected to the pure water in the pure water supply path 2.
OFF state for a certain period of time from the beginning of the introduction of the chemical
Become a PII^TwoThe output of the D operation unit 43 is prohibited (PI
I^TwoD operation unit 43 is deactivated), and after a predetermined time elapses, O
Switch to N state and PII ^TwoAllow the output of D operation unit 43
(PII^TwoThe D operation unit 43 is operated). like this
The reason for providing the switch 44 is as follows.

Following the initial state of replacement in which the pure water supply valve 8 is opened and pure water is flowing in the pure water supply path 2, the chemical supply valve 10 is opened and the chemical liquid flows in the chemical supply path 11. At the beginning of the start of the supply of the treatment liquid, the rising of the chemical liquid flow rate in the chemical liquid supply path 11 is slow, so the current chemical liquid flow value b1 detected by the chemical liquid flow sensor 18 shows a value considerably lower than the target value. As a result, the current concentration b3 of the processing liquid output from the current concentration calculation unit 50 is considerably reduced, and the concentration deviation c3 is increased. In an attempt to cancel the density deviation c3, the PII ² D calculation unit 43 outputs a large density control operation amount. Therefore, the so-called overshoot occurs in which the concentration manipulation amount of the processing liquid becomes too large, and an excessive chemical solution is introduced into pure water. A switch 44 is provided to avoid such an overshoot at the beginning of the supply of the processing liquid, and the concentration of the processing liquid is controlled only by the target concentration a3 of the processing liquid at the beginning of the supply of the processing liquid. . In the present embodiment, the switch 44 is controlled by a program timer, but the switch 44 may be switched according to the value of the concentration deviation c3 of the processing liquid.

The concentration-flow rate converter 46 converts the concentration manipulated variable d3 of the processing liquid into the chemical fluid flow manipulated variable d1. For this conversion, the concentration-flow rate converter 46 sets the pure water flow rate target value a
2. The reason is as follows. In the case of the present embodiment, since the pure water flow rate in the pure water supply path 2 is controlled by the pure water flow rate feedback control unit 70, the fluctuation of the pure water flow rate is small. Therefore, in the steady state where the flow rate of the chemical in the chemical supply path 11 is stable, the concentration control of the processing liquid can be performed more stably by using the pure water flow rate target value a2.

The concentration-flow rate converter 46 obtains the chemical liquid flow rate operation amount d1 by the following equation (3). d1 = 1000 × d3 × a2 / (C ₀ −d3) (3) where a2 is the pure water flow rate target value [liter / min] d1 is the chemical liquid flow rate operation amount [cc / min] d3 is the processing Liquid concentration operation amount [%] C ₀ is the concentration of drug substance solution [%]

This chemical liquid flow rate operation amount d1 is given to the flow rate-voltage conversion unit 47. The flow rate-voltage converter 47 converts the chemical liquid flow operation amount d1 into a chemical liquid flow operation voltage Vd1 to be applied to the electropneumatic converter 20 according to the following equation (4). Vd1 = d1 × Ac + Bc (4) where Vd1 is the chemical liquid flow operation voltage [V] d1 is the chemical liquid flow operation amount [cc / min] Ac is each of the electropneumatic converter 20 and the chemical liquid pressure regulator 19 The constant Bc determined by the specification and the valve opening of the chemical liquid introduction valve 9 is a constant determined by the pure water pressure reference value P ₀ and the specification of the chemical liquid pressure regulator 19 The above constants Ac and Bc can be obtained by experiments.

As described above, the chemical concentration feedback control section 40A
Is set by adjusting the chemical liquid flow rate operation amount d1 so as to cancel the deviation c3 between the target concentration a3 of the processing liquid and the current concentration b3. Even if the chemical solution introduction valve 9 undergoes thermal deformation due to the flow of water, the concentration of the treatment solution fluctuates quickly even if the amount of the chemical solution introduced into pure water changes and the concentration of the treatment solution fluctuates. can do.

(3) Operation of the Pure Water Pressure Fluctuation Feedback Unit 60A The subtractor 61 of the pure water pressure fluctuation feedback unit 60A determines a predetermined pure water pressure value from the pure water pressure current value e2 detected by the pure water pressure sensor 7. By subtracting the water pressure reference value P ₀ , a pressure fluctuation value Δe2 of the pure water pressure current value e2 is obtained. The pure water pressure reference value P ₀ is determined by experimentally obtaining the pure water pressure when a reference amount of pure water flows through the pure water supply path 2.

The pressure fluctuation value Δe2 obtained by the subtracter 61 is given to the pressure-voltage converter 62. The pressure-voltage converter 62 converts the pressure fluctuation value Δe2 into a voltage ΔVe2 for correcting the chemical liquid flow rate operation voltage Vd1 by using a linear equation experimentally obtained in relation to the specifications of the electropneumatic converter 20 and the like. Convert. The corrected chemical flow rate operation voltage Vd1 ′ is obtained by adding the chemical flow rate operation voltage Vd1 output from the chemical concentration feedback control unit 40A and the correction voltage ΔVe2 by the adder 63. This chemical liquid flow operation voltage Vd
1 ′ is provided to the electropneumatic converter 20. The electropneumatic converter 20 provides the pilot pressure according to the chemical flow rate operation voltage Vd1 'to the chemical pressure regulator 19. The chemical liquid pressure regulator 19 adjusts the chemical liquid pressure (as a result, the chemical liquid flow rate) in the secondary chemical liquid supply passage 11 so as to match the pilot pressure.

When the pure water pressure in the pure water supply path 2 fluctuates, the pure water pressure fluctuation feedback section 60A changes the chemical liquid flow rate operation voltage Vd1 following the pressure fluctuation. as a result,
When the pure water pressure in the pure water supply path 2 increases, the chemical liquid pressure in the chemical liquid supply path 11 increases accordingly, and conversely, when the pure water pressure decreases, the chemical liquid pressure decreases accordingly. That is, since the pressure of the pure water in the pure water supply path 2 fluctuates and the pressure difference between the chemical liquid pressure on the inlet side and the pure water pressure on the outlet side of the chemical liquid introducing valve 9 changes, the pure water pressure is introduced into the pure water. Even if the flow rate of the chemical solution fluctuates, the pressure of the chemical solution in the chemical solution supply passage 11 is quickly adjusted to return the differential pressure between the inlet side and the outlet side of the chemical solution introduction valve 9 to a predetermined value. The resulting fluctuation in the concentration of the processing solution can be suppressed.

Even if the pure water pressure fluctuation feedback section 60A is not provided, if the concentration of the processing liquid fluctuates due to the fluctuation of the pure water pressure, the above-described chemical liquid concentration feedback control section 40A operates to operate the processing liquid liquid. The chemical solution flow operation voltage Vd1 is adjusted so that the concentration returns to the target value. However, after the pure water pressure fluctuates,
There is a delay until the fluctuation in the concentration of the processing solution is detected.
On the other hand, if the pure water pressure fluctuation feedback unit 60A is provided, when the pure water pressure fluctuation occurs, the chemical liquid flow rate operation voltage Vd1 is immediately corrected regardless of the presence or absence of the concentration of the processing liquid. Can be quickly suppressed.

(4) Operation of the pure water flow rate feedback control unit 70 The subtracter 71 of the pure water flow rate feedback control unit 70 uses the pure water flow rate sensor 4 based on the pure water flow rate target value a2 set by the target value setting unit 30A. The pure water flow deviation c2 is calculated by subtracting the present pure water flow value b2 detected in step (1). The pure water flow rate deviation c2 is given to the PID calculation unit 72. The PID calculation unit 72 calculates the pure water flow rate deviation c2 given from the subtractor 71.
Proportional operation (P operation) for determining the pure water flow operation amount in proportion to the integral water operation (I operation) for determining the pure water flow operation amount in proportion to the integral of the pure water flow deviation c2; Deviation c
And a differential operation (D operation) for determining a pure water flow manipulated variable in proportion to the derivative of 2.
Is calculated as a pure water flow control operation amount that cancels out. The operation amount of the pure water flow control is added to an adder 74 via a switch 73.
Given to.

The switch 73 is turned off for a certain period of time from the point when the pure water supply valve 8 is opened and the pure water starts to flow through the pure water supply passage 2 to inhibit the output of the PID calculation unit 72. (The PID calculation unit 72 is deactivated.) After a certain time has elapsed, the state is switched to the ON state, and the output of the PID calculation unit 72 is permitted (the PID calculation unit 72 is activated). The switch 73 is provided to avoid an overshoot in the initial stage when pure water starts flowing to the pure water supply path 2, similarly to the switch 44 described in the chemical concentration feedback control unit 40 </ b> A.

The adder 74 adds the pure water flow control operation amount given from the PID calculation unit 72 via the switch 73 to the pure water flow target value a2 given from the target value setting unit 30A. The pure water flow operation amount d2 obtained by adding the pure water flow target value a2 and the pure water flow control operation amount is given to the flow-voltage converter 75.

The flow-voltage conversion unit 75 calculates the pure water flow operation amount d2 given from the adder 74 based on the following equation (5).
It is converted to the pure water flow operation voltage Vd2. Vd2 = (d2-Cc) / Dc (5) Here, Vd2 is a pure water flow operation voltage [V] d2 is a pure water flow operation amount [liter / min] Cc and Dc are electropneumatic converters 6 And the constants determined by the specifications of the pure water pressure regulator 3 and the resistance coefficient of the pure water supply path 2 The above constants Cc and Dc can be obtained by experiments.

The pure water flow operation voltage Vd 2 is applied to the electropneumatic converter 6. The electropneumatic converter 6 operates at a pure water flow rate operation voltage Vd.
2 is provided to the pure water pressure controller 3.
The pure water pressure adjuster 3 adjusts the pure water pressure (as a result, the pure water flow rate) in the secondary-side pure water supply path 2 so as to match the pilot pressure.

The pure water flow rate feedback controller 70 calculates a pure water flow manipulated variable d2 that cancels the deviation c2 between the pure water flow target value a2 and the pure water flow present value b2, and calculates the pure water flow manipulated variable. Since the pure water flow rate in the pure water supply path 2 is controlled by adjusting the pure water pressure regulator 3 based on d2, it is possible to suppress the concentration fluctuation of the processing solution caused by the pure water flow fluctuation. it can. Even if the pure water flow rate feedback control unit 70 is not provided, if the concentration of the processing liquid fluctuates due to the fluctuation of the pure water flow rate, the above-mentioned chemical liquid concentration feedback control unit 40A operates to set the concentration of the processing liquid to the target value. Is adjusted so as to return to. However, after the pure water flow fluctuates,
There is a delay until the fluctuation in the concentration of the processing solution is detected.
On the other hand, when the pure water flow rate feedback control unit 70 is provided, when the pure water flow rate fluctuation occurs, the pure water flow rate operation amount d2 is immediately adjusted regardless of the presence or absence of the processing liquid concentration fluctuation. The effect of the fluctuation can be suppressed promptly.

As described above, according to the first embodiment described above, the chemical solution flow target value a1 and the pure water flow target value a2, each of which changes with the passage of time, are set. Sets the chemical liquid flow operation voltage Vd1 so as to suppress the concentration fluctuation of the processing liquid. On the other hand, the pure water pressure fluctuation feedback unit 60A corrects the set chemical liquid flow operation voltage Vd1 according to the fluctuation of the pure water pressure. Further, the pure water flow rate feedback control unit 70 adjusts the pure water flow rate operation voltage Vd2 so as to suppress the fluctuation of the pure water flow rate. Therefore, according to the present embodiment, the concentration of the processing liquid can be accurately and quickly made to match the target value.

A6: Variation Pattern of Target Value Two examples of temporal variation patterns of the chemical liquid flow rate target value a1 and the pure water flow rate target value a2 will be described below. (1) Refer to FIG. In this example, the target value setting unit 30
A is a chemical solution flow rate target value a1 and a pure water flow from the time when the supply of the processing liquid is started to the substrate processing tank 1 filled with pure water to the time when the inside of the substrate processing tank 1 is replaced with the processing liquid. Each initial target value of the flow rate target value a2 is set higher than each subsequent target value. Since the ratio of the chemical solution flow target value a1 to the pure water flow target value a2 is constant over time, when the chemical solution flow target value a1 and the pure water flow target value a2 are set, the concentration of the treatment liquid that is uniquely determined The target value a3 also becomes constant over time. According to this example, since a large amount of the processing liquid is supplied to the substrate processing tank 1 in the initial stage of the replacement of the substrate processing tank 1, the speed at which the pure water in the substrate processing tank 1 is replaced with the processing liquid increases. , The processing efficiency of the replacement can be increased.

(2) Referring to FIG. In this example, the target value setting unit 30A includes the substrate processing tank 1 filled with pure water.
The initial target value of the chemical liquid flow rate target value a1 is changed from the time when the supply of the processing liquid is started to the time when the inside of the substrate processing tank 1 is replaced with the processing liquid to the subsequent chemical liquid flow rate target value a1.
In addition, since the target value a2 of the pure water flow rate is set to be constant, the target concentration value a3 of the processing liquid in the initial stage of the replacement becomes higher. In other words, since the processing liquid having a high concentration is supplied to the substrate processing tank 1 in the initial stage of the replacement, the rise of the average concentration of the processing liquid in the substrate processing tank 1 initially filled with pure water is quickened. When the average concentration of the processing liquid in the substrate processing tank 1 has increased to some extent, the processing liquid having a predetermined concentration is supplied to the substrate processing tank 1 by returning the target value a1 of the chemical solution flow rate to a predetermined target value. According to this example, since the rise of the average concentration of the processing liquid in the substrate processing tank 1 is fast, the processing efficiency of the replacement can be increased.

A7: Modifications (1) The current concentration b3 of the processing solution may be measured by a concentration measuring device. Although not shown, this concentration measuring device is provided in the pure water supply path 2 on the outlet side of the chemical solution mixing section 5 in FIG. However, since the concentration measuring device is generally expensive, if the current concentration b3 of the processing liquid is obtained by calculation as in the above-described embodiment, this type of substrate processing apparatus can be realized at low cost.

(2) When the pure water flow rate control is not performed, the concentration-flow rate converter 46 refers to the pure water flow rate sensor 4 instead of the current pure water flow rate a2.
Alternatively, the pure water flow rate current value b2 obtained by actual measurement may be used.

B: Second Embodiment B1: Configuration of Second Embodiment Apparatus In the substrate processing apparatus according to the present embodiment, the configurations of a pure water supply system and a chemical solution supply system to the substrate processing tank 1 are shown in FIG. Since it is the same as that of the first embodiment (see the above-mentioned items A1 to A3), the description is omitted here.

B4: Schematic Configuration of Control System FIG. 6 shows the configuration of the control system of this embodiment. This control system is functionally distinguished from a target value setting unit 30B, a chemical concentration feedback control unit 40B, a current concentration value calculation unit 50, a pure water pressure fluctuation feedback unit 60A, and a pure water flow rate feedback control unit 70. ing. Among them, the current concentration value calculation section 50, the pure water pressure fluctuation feedback section 60A, and the pure water flow rate feedback control section 7
Each configuration of 0 is the same as that of the first embodiment (see item A4 described above), and the description is omitted here. Hereinafter, portions different from the first embodiment will be described.

The target value setting section 30B of the present embodiment calculates the target concentration a3 of the processing liquid, which changes with time.
And the pure water flow rate target value a2 are set. In this embodiment, since the target concentration a3 of the processing liquid is set, the chemical concentration feedback controller 40B includes the target concentration calculator 41 provided in the chemical concentration feedback controller 40A of the first embodiment. Not. That is, the set processing solution concentration target value a3 is directly supplied to the subtractor 42 and the adder 45, respectively.

B5: Operation of the Second Embodiment The operation of the second embodiment is substantially the same as the operation of the first embodiment (see item A5 described above). However, in the subtractor 42 of the chemical concentration feedback control unit 40B, the target value setting unit 30
The processing solution concentration deviation c3 is determined from the processing solution concentration target value a3 set in B and the processing solution concentration present value b3 given from the current concentration calculating unit 50. In addition, the adder 45 adds the concentration control operation amount of the processing liquid provided from the PII ² D calculation unit 43 to the processing liquid concentration target value a3 set by the target value setting unit 30B.

According to this embodiment, the same effect as that of the first embodiment can be obtained. In particular, the apparatus of the second embodiment is effective when it is desired to manage the target concentration a3 of the processing liquid and the target value a2 of the pure water flow rate.

B6: Change Pattern of Target Value An example of a temporal change pattern of the target concentration a3 of the processing liquid and the target pure water flow rate a2 will be described below. Please refer to FIG. In this example, the target value setting unit 30 </ b> B starts the supply of the processing liquid to the substrate processing tank 1 filled with pure water until the processing liquid in the substrate processing tank 1 is completely replaced with the processing liquid. While the concentration target value a3 of the treatment liquid is set to be constant, the purifying water flow target value a2 is set smaller than the initial target value as the replacement with the treatment liquid proceeds.
When the target concentration a3 of the processing liquid and the target value a2 of the pure water flow rate are set, the target value a1 of the chemical liquid flow rate is uniquely determined. Here, since the concentration target value a3 is constant, the chemical liquid flow target value a1 becomes smaller as the replacement with the treatment liquid proceeds, similarly to the pure water flow target value a2. As a result, the flow rate of the processing liquid supplied to the substrate processing tank 1 decreases as the replacement with the processing liquid progresses. As the replacement with the processing liquid progresses, the average concentration of the processing liquid in the substrate processing tank 1 approaches the target value, but the rate of increase decreases.
During this time, the processing liquid in the substrate processing tank 1 overflows with the supply of the processing liquid. According to this example, if the average concentration of the processing liquid in the substrate processing tank 1 approaches the target value,
Since the amount of the processing liquid supplied to the substrate processing tank 1 is reduced, the amount of the processing liquid discharged from the substrate processing tank 1 is also reduced, and the processing liquid required for replacement can be saved.

C: Third Embodiment C1: Configuration of Apparatus of Third Embodiment In the substrate processing apparatus according to the present embodiment, the configurations of a pure water supply system and a chemical solution supply system to the substrate processing tank 1 are shown in FIG. Since it is the same as that of the first embodiment (see the above-mentioned items A1 to A3), the description is omitted here.

C4: Schematic Configuration of Control System FIG. 8 shows the configuration of the control system of this embodiment. This control system is functionally distinguished from a target value setting unit 30C, a chemical solution concentration feedback control unit 40C, a current concentration value calculation unit 50, a pure water pressure fluctuation feedback unit 60A, and a pure water flow rate feedback control unit 70. ing. Among them, the current concentration value calculation section 50, the pure water pressure fluctuation feedback section 60A, and the pure water flow rate feedback control section 7
Each configuration of 0 is the same as that of the first embodiment (see item A4 described above), and the description is omitted here. Hereinafter, portions different from the first embodiment will be described.

The target value setting section 30C of the present embodiment calculates the processing liquid concentration target value a3 which changes with time.
And the chemical solution flow rate target value a1 are set. In the present embodiment, the chemical liquid concentration feedback control unit 40C calculates the pure water flow target value a2 based on the treatment liquid concentration target value a3 and the chemical liquid flow target value a1 by calculation. 48. The pure water flow target value calculation unit 48 calculates the pure water flow target value a2 by the following equation (6). a2 = a1 × (C ₀ −a3) / (1000 × a3) (6) where a1 is the chemical solution flow target value [cc / min] a2 is the pure water flow target value [liter / min] a3 is , Target concentration of treatment solution [%] C ₀ is the concentration of drug substance solution [%]

The pure water flow target value a2 calculated by the pure water flow target value calculation section 48 is given to the concentration-flow rate conversion section 46 and the pure water flow rate feedback control section 70. Further, the target concentration a3 of the processing liquid set by the target value setting unit 30C is directly given to the subtractor 42 and the adder 45.

C5: Operation of the Third Embodiment The operation of the third embodiment is almost the same as the operation of the first embodiment (see item A5 described above). However, in the subtracter 42 of the chemical concentration feedback control unit 40C, the target value setting unit 30
The concentration deviation c3 of the processing solution is obtained from the target concentration value a3 of the processing solution set in C and the current concentration value b3 of the processing solution given from the current concentration value calculation unit 50. In addition, the adder 45 adds the concentration control operation amount of the processing liquid provided from the PII ² D calculation unit 43 to the processing liquid concentration target value a3 set by the target value setting unit 30C. Furthermore, the concentration-
The flow rate converter 46 converts the concentration control amount d3 of the processing liquid into the chemical liquid flow rate control amount d1 by using the pure water flow rate target value a2 calculated by the pure water flow rate target value calculator 48. Note that, instead of the pure water flow target value a2, the pure water flow current value b2
May be used. Further, the subtracter 71 of the pure water flow rate feedback control unit 70 calculates the pure water flow current value b2 detected by the pure water flow sensor 4 from the pure water flow target value a2 calculated by the pure water flow target value calculation unit 48. Is subtracted to calculate the pure water flow rate deviation c2.

According to this embodiment, the same effect as that of the first embodiment can be obtained. In particular, the apparatus of the third embodiment is effective when it is desired to manage the target concentration a3 of the processing liquid and the target value a1 of the chemical flow rate.

C6: Variation Pattern of Target Value An example of a temporal variation pattern of the target concentration a3 of the treatment liquid and the target value a1 of the chemical liquid flow will be described below. Please refer to FIG. In this example, the target value setting unit 30 </ b> C starts the supply of the processing liquid to the substrate processing tank 1 filled with pure water until the substrate processing tank 1 is completely replaced with the processing liquid. The initial target value of the processing solution concentration target value a3 is set to be larger than the subsequent processing solution concentration target value, while the chemical solution flow target value a1 is set to be constant. When the processing solution concentration target value a3 and the chemical solution flow target value a1 are set, the pure water flow target value a2 is uniquely determined. here,
Since the initial target value of the concentration target value a3 is set high and the chemical liquid flow target value a1 is constant, the initial target value of the pure water flow target value a2 becomes low. As a result, similarly to the change pattern in FIG. 5 of the first embodiment, the concentration of the processing liquid supplied to the substrate processing tank 1 in the initial stage of replacement increases, and the average concentration of the processing liquid in the substrate processing tank 1 rises. Can be faster.
According to this example, when changing the concentration of the processing solution, it is not necessary to operate the chemical solution flow rate (as a result, the pure water flow rate is operated). Occurrence can be suppressed.

D: Fourth Embodiment D1: Fourth Embodiment Configuration of Apparatus In the substrate processing apparatus according to this embodiment, the configurations of a pure water supply system and a chemical solution supply system to the substrate processing tank 1 are shown in FIG. Since it is the same as that of the first embodiment (see the above-mentioned items A1 to A3), the description is omitted here.

D4: Schematic Configuration of Control System FIG. 10 shows the configuration of the control system of this embodiment. This control system is functionally distinguished from a target value setting unit 30D, a chemical liquid flow rate feedback control unit 80, and a pure water pressure fluctuation feedback unit 60B.
It is composed of

The target value setting section 30D of this embodiment sets a chemical solution flow target value a1 that changes with the passage of time and a pure water flow target value a2 that is constant over time. The target value a2 of the pure water flow rate is given to the electropneumatic converter 6 as the pure water flow operation voltage Vd2.

The chemical liquid flow rate feedback control unit 80 obtains a deviation c1 between the chemical liquid flow rate target value a1 and the current chemical liquid flow rate b1, and cancels the chemical liquid flow rate deviation c1 so as to cancel the chemical liquid flow rate deviation c1.
Adjust The chemical liquid flow rate operation amount d1 is converted into a chemical liquid flow rate operation voltage Vd1 and provided to the pure water pressure fluctuation feedback unit 60B.

[0124] Pure water pressure fluctuation feedback portion 60B, similarly to the pure water pressure fluctuation feedback section 60A described in the first embodiment, the voltage according to the pressure variation of the pure water pressure current value e2 with respect to pure water pressure reference value P ₀ By adding and correcting ΔVe2 to the chemical flow rate operation voltage Vd1, the chemical pressure in the chemical liquid supply path 11 is adjusted to follow the fluctuation of the pure water pressure in the pure water supply path 2. However, the pure water pressure fluctuation feedback unit 60B of this embodiment
Is the pure water flow rate current value b2 detected by the pure water flow rate sensor 4
And a pure water pressure current value calculation unit 64 for calculating the pure water pressure current value e2 from the above. Therefore, according to the pure water pressure fluctuation feedback unit 60B, it is not necessary to provide the pure water pressure sensor 7 for detecting the pure water pressure in the pure water supply path 2.

The pure water pressure current value calculating section 64 calculates the pure water pressure current value e2 according to the following equation (7). e2 = b2 × Ec + Fc (7) where b2 is the current pure water flow rate [liter / min] e2 is the pure water pressure current value [Kgf / min] Ec and Fc are the flow paths of the pure water supply path 2 Constants Determined by Resistance Constants Ec and Fc are determined by experiments.

D5: Operation of the Example Apparatus The temporally constant pure water flow target value a2 set by the target value setting section 30D is supplied to the electropneumatic converter 6 by the pure water flow operation voltage Vd2.
As a result, the pressure and flow rate of the pure water in the pure water supply path 2 are constantly adjusted by the pure water pressure regulator 3.

On the other hand, the chemical liquid flow rate target value a1 that changes with time set by the target value setting section 30D is given to the subtractor 81 of the chemical liquid flow rate feedback control section 80. The subtracter 81 obtains a deviation c1 between the target chemical flow rate a1 and the current chemical flow rate value b1 detected by the chemical flow sensor 18. This chemical liquid flow deviation c1 is given to the PII ² D calculation unit 82.
The PII ² D calculation unit 82 has the same configuration as the PII ² D calculation unit 43 provided in the chemical concentration feedback control unit 40A of the first embodiment, and performs P operation, I operation, I ² operation, and D operation. A control amount of the chemical flow control that cancels the chemical flow deviation c1 is calculated by a control law including the above. The control amount of the chemical liquid flow control is provided to the adder 84 via the switch 83.

The adder 84 obtains the chemical liquid flow control amount d1 by adding the chemical liquid flow control operation amount to the chemical liquid flow target value a1. The chemical liquid flow rate operation amount d1 is converted into a chemical liquid flow rate operation voltage V amount d1 by the flow rate-voltage converter 85 and output. The switch 83 is similar to the switch 44 provided in the chemical concentration feedback control unit 40A of the first embodiment.
In order to avoid overshoot at the start of chemical introduction,
During a certain period of time from the start of the introduction of the chemical solution, the PII ² D calculation unit 82
Is deactivated.

For example, when the heated pure water or the chemical flows and the chemical introduction valve 9 is thermally deformed and its flow characteristic changes, control is performed so that the chemical pressure in the chemical supply path 11 becomes constant. However, the flow rate of the chemical solution introduced into the pure water is not constant. As a result, the concentration of the processing liquid supplied to the substrate processing tank 1 changes. However, according to the present embodiment, the chemical liquid flow rate operation amount d1 is adjusted so as to cancel the chemical liquid flow rate deviation c1, so that the concentration fluctuation of the processing liquid due to the fluctuation of the chemical liquid flow rate can be suppressed.

The operation of the pure water pressure fluctuation feedback section 60B is the same as that of the first embodiment except that the present pure water pressure value e2 is calculated.
Since it is the same as the pure water pressure fluctuation feedback section 60A in the embodiment, the description here is omitted.

According to the present embodiment, the chemical liquid flow rate target value a1 set by the target value setting section 30D and the chemical liquid flow rate sensor 18
The chemical liquid flow rate feedback control unit 80 sets the chemical liquid flow rate manipulated variable d so as to cancel the deviation c1 from the current chemical liquid flow rate value b1 detected in the step (c).
1 to set the chemical liquid flow rate operation voltage Vd1. Based on the chemical liquid flow operation voltage Vd1, the liquid pressure regulator 19
Adjusts the chemical pressure so that the chemical flow rate in the chemical supply path 11 matches the target value. At this time, when the pure water pressure in the pure water supply path 2 fluctuates, the pure water pressure fluctuation feedback unit 60B corrects the chemical liquid flow rate operation voltage Vd1 so as to fluctuate the chemical liquid pressure following this pressure fluctuation. As a result, the differential pressure between the inlet-side pure water pressure and the outlet-side chemical solution pressure of the chemical solution introduction valve 9 is appropriately maintained regardless of the pressure fluctuation in the pure water supply path 2, so that the chemical solution at the target flow rate can be obtained. Introduced into pure water.

D6: Variation Pattern of Target Value An example of a temporal variation pattern of the chemical liquid flow rate target value a1 and the pure water flow rate target value a2 is the same as the change pattern of the target value of the first embodiment shown in FIG. Therefore, the description is omitted here.

D7: Modifications (1) In this embodiment, the pure water pressure fluctuation feedback section 60A used in the first embodiment can of course be used in place of the pure water pressure fluctuation feedback section 60B. is there. Also, conversely,
In the first to third embodiments, the pure water pressure fluctuation feedback unit 60A
Instead, a pure water pressure fluctuation feedback unit 60B can be used.

(2) In the present embodiment, the chemical solution flow rate sensor 18 actually measures the current chemical solution flow rate value b1 to be supplied to the subtractor 81 of the chemical solution flow rate feedback control section 80. Instead of this, the chemical liquid flow rate current value b1 may be calculated from the pure water flow rate current value b2 detected by the pure water flow rate sensor 4 and the treatment liquid concentration current value b3 measured by the concentration measuring device. Good. Although not shown, this concentration measuring device is disposed in the pure water supply path 2 on the outlet side of the chemical solution mixing section 5 in FIG.

E: Fifth Embodiment E1: Configuration of Apparatus of Fifth Embodiment In the substrate processing apparatus according to the present embodiment, the configurations of a pure water supply system to the substrate processing tank 1 and a chemical solution supply system are shown in FIG. Since it is the same as that of the first embodiment (see the above-mentioned items A1 to A3), the description is omitted here.

E4: Schematic Configuration of Control System FIG. 11 shows the configuration of the control system of the present embodiment. This control system includes a target value setting unit 30E, a pure water pressure fluctuation feedback unit 60B, a pure water flow rate feedback control unit 70, and a pure water flow present value calculation unit 90 when functionally distinguished.

The target value setting section 30E of this embodiment sets a temporally constant chemical liquid flow target value a1 and a pure water flow target value a2 that changes with time. The chemical liquid flow rate target value a1 is provided to the adder 63 of the pure water pressure fluctuation feedback unit 60B as the chemical liquid flow rate operation voltage Vd1.

Since the configuration of the pure water pressure fluctuation feedback section 60B is the same as that of the fourth embodiment, the description is omitted here. The configuration of the pure water flow rate feedback controller 70 is the same as that of the first embodiment. However, the pure water flow current value b2 calculated by the pure water flow current value calculation unit 90 is given to the subtractor 71. The pure water flow rate current value calculation section 90 is provided with the chemical liquid flow rate sensor 18.
From the chemical solution flow current value b1 measured in step (1) and the processing solution concentration current value b3 measured by the processing solution concentration measuring device, the pure water flow current value b2 is calculated using the following equation (8). b2 = b1 × (C ₀ −b3) / (1000 × b3) (8) where b1 is the current value of the chemical flow rate [cc / min] b2 is the current value of the pure water flow rate [liter / min] b3 is , Treatment solution concentration present value (actual measurement value) [%] C ₀ is the concentration of the drug substance solution [%]

E5: Operation of the Embodiment Apparatus The temporally constant chemical liquid flow rate target value a1 set by the target value setting section 30E is supplied to the pure water pressure fluctuation feedback section 60B as the chemical liquid flow rate operation voltage Vd1. Pure water pressure fluctuation feedback section 6
The operation of 0B is the same as that of the pure water pressure fluctuation feedback unit 60A in the first embodiment, except that the current pure water pressure value e2 is obtained by calculation, and therefore the description thereof is omitted.

The pure water flow rate feedback control unit 70 obtains a pure water flow rate deviation c2 from the pure water flow rate target value a2 and the pure water flow rate current value b2 given from the pure water flow rate current value calculation unit 90. A pure water flow operation amount d2 that cancels the deviation c2 is calculated, and the pure water flow operation amount d2 is calculated as a pure water flow operation voltage Vd2.
And the result is given to the electropneumatic converter 6. The specific operation is the first
Since it is the same as the pure water flow rate feedback control unit 70 of the embodiment, the description here is omitted.

According to the present embodiment, the liquid pressure regulator 19 adjusts the chemical pressure in the chemical supply path 11 to a constant value based on the chemical flow rate operation voltage Vd1 set to a constant value. At this time, when the pure water pressure in the pure water supply path 2 fluctuates, the pure water pressure fluctuation feedback unit 60B corrects the chemical liquid flow rate operation voltage Vd1 so as to fluctuate the chemical liquid pressure following this pressure fluctuation.
As a result, irrespective of the pressure fluctuation in the pure water supply path 2, the pressure difference between the inlet-side pure water pressure of the chemical liquid introduction valve 9 and the outlet-side chemical liquid pressure is kept constant, so that a certain amount of the chemical liquid is supplied. Introduced into pure water. On the other hand, when the pure water flow rate in the pure water supply path 2 fluctuates, the deviation c2 between the pure water flow target value a2 and the pure water flow current value b2 calculated by the pure water flow current value calculation unit 90 is eliminated. Then, the pure water flow rate feedback control unit 70 operates to suppress the fluctuation of the pure water flow rate.

E6: Change Pattern of Target Value FIG. 12 shows an example of a time-dependent change pattern of the chemical solution flow target value a1 and the pure water flow target value a2. The target value setting unit 30E according to the present embodiment includes a substrate processing tank 1 filled with pure water.
While the supply of the processing liquid into the substrate processing tank is started and until the inside of the substrate processing bath 1 is replaced with the processing liquid, the chemical liquid flow rate target value a1 is set to be temporally constant, while the pure water flow rate target value a2 is set. Is set higher than the subsequent pure water flow rate target value. That is, in the initial stage of the replacement, a processing liquid having a low concentration is supplied to the substrate processing tank 1, and when the average concentration of the processing liquid in the substrate processing tank 1 has increased to some extent, the pure water flow rate target value a2 is returned to a predetermined value. Then, a processing solution having a predetermined concentration is supplied to the substrate processing tank 1. If such a target value is set, a processing liquid having a low concentration is supplied into the substrate processing tank 1 filled with pure water in the initial stage of replacement, so that the average concentration of the processing liquid in the substrate processing tank 1 is increased. Can be kept small.
In the graph showing the change in the concentration unevenness of the processing solution in the substrate processing bath 1 in FIG. , Respectively.

E7: Modifications (1) In the present embodiment, the pure water flow current value b2 calculated by the pure water flow current value calculation unit 90 is given to the pure water flow feedback control unit 70. The value b2 may be detected by the pure water flow sensor 4.

(2) Instead of the pure water pressure fluctuation feedback section 60B, the pure water pressure fluctuation feedback section 60 described in the first embodiment is used.
A can also be used.

F: Sixth Embodiment F1: Configuration of Sixth Embodiment FIG. 13 shows a schematic configuration of a substrate processing apparatus according to this embodiment. In FIG. 13, components denoted by the same reference numerals as those in FIG. 1 have the same configuration as the device of the first embodiment, and a description thereof will be omitted. Hereinafter, differences from the first embodiment will be described.

In the apparatus of the first embodiment shown in FIG. 1, the chemical pressure is controlled by the chemical pressure regulator 19 provided in the chemical supply path 11 so that the chemical at a constant flow rate is supplied to the chemical introduction valve 9.
And introduced into the pure water supply path 2. On the other hand, the device of the sixth embodiment replaces the chemical liquid introduction valve 9, the chemical liquid supply valve 10, and the chemical liquid pressure regulator 19 of the first embodiment,
A chemical liquid flow control valve 21 is provided in the chemical liquid supply passage 11, and a pilot pressure is applied from the electropneumatic converter 20 to the chemical liquid flow control valve 21, whereby the opening of the valve of the chemical liquid flow control valve 21 is operated to supply the chemical liquid. It is configured to directly control the flow rate of the chemical solution in the passage 11.

The structure of the chemical liquid flow control valve 21 will be described with reference to FIG. The chemical liquid flow control valve 21 is connected to the introduction valve connection pipe 12 that is provided in the middle of the pure water supply path 2. The bottom surface of the chemical liquid flow control valve 21 and a bottomed hole drilled in the introduction valve connecting pipe 12 form a valve chamber 21a.
The valve chamber 21a is connected to the chemical solution supply path 11 through a connection hole 21b. Further, the valve chamber 21a is
g, it is connected to the pure water flow path 12a of the introduction valve connecting pipe 12 through communication. The valve chamber 21a is provided with a throttle valve 21c that opens and closes the chemical solution inlet 21g and adjusts the opening degree. The proximal end of the throttle valve 21c is connected and supported by a support 21e that slides and displaces in the valve body 21d. The support 9e is pressed downward by a spring 21h. In a state where air is not supplied to the pilot air supply port 21i, the support pair 21e and the throttle valve 21c are pressed downward by the spring force of the spring 21h, and at this time, the chemical liquid introduction port 21g is closed. The above configuration is common to the configuration of the chemical liquid introduction valve 9 described in the first embodiment.

The difference from the chemical liquid introduction valve 9 is that when air (pilot pressure) is supplied to the pilot air supply port 21i, the throttle valve 21c rises integrally with the support 21e against the spring force of the spring 21h. That is, the throttle valve 21 stops at a position where the pilot pressure and the spring force are balanced, and the chemical solution inlet 21g is opened at an opening corresponding to the stop position. That is, by controlling the opening degree of the chemical liquid flow control valve 21 according to the pilot pressure given from the electropneumatic converter 20, the flow rate of the chemical liquid flowing through the chemical liquid supply path 11, that is, pure water The flow rate of the chemical solution introduced into the pure water in the supply path 2 is directly controlled.

F4: Schematic Configuration of Control System The configuration of the control system of the apparatus of this embodiment is almost the same as that of the first embodiment shown in FIG. 3, so that the detailed description is omitted here. However, since it is necessary to convert the chemical flow rate operation amount d1 calculated by the concentration-flow rate conversion unit 46 into the chemical flow rate operation voltage Vd1 corresponding to the chemical flow rate control valve 21, the conversion formula used by the flow rate-voltage conversion unit 47 is used. (Equation (4) described in the first embodiment) needs to be changed. Specifically, the constant Ac in the equation (4) is changed to a constant determined from the specifications of the electropneumatic converter 20 and the chemical liquid flow rate control valve 21, and the constant Bc is changed to the pure water pressure reference value P ₀ and the chemical liquid flow rate. The value is changed to a constant determined from the specification of the control valve 21. These constants Ac and Bc can be obtained by experiments. For the same reason, the pressure-voltage converter 6
The conversion formula used in Step 2 (the pressure fluctuation value Δe2 of pure water is calculated as the correction voltage Δ
The primary equation for conversion to Ve2) is also experimentally determined in consideration of the specifications of the electropneumatic converter 20 and the chemical liquid flow control valve 21, and the like.

F5: Operation of the embodiment apparatus The operation of the embodiment apparatus is the same as that of the first embodiment except for the process of controlling the flow rate of the chemical solution by the chemical flow control valve 21, so that the operation of the same components will be described. The description will be omitted, and the following description will focus on the control process of the chemical solution flow rate by the chemical solution flow control valve 21.

The chemical concentration feedback control section 40A calculates a chemical flow rate operation amount that cancels out the concentration deviation of the processing liquid, and converts this to a chemical flow rate operation voltage Vd1 corresponding to the chemical flow rate control valve 21.
And supplied to the pure water pressure fluctuation feedback section 60A. on the other hand,
The pure water pressure fluctuation feedback unit 60A is configured such that when the pure water pressure in the pure water supply path 2 increases, the flow rate of the chemical solution introduced into the pure water decreases.
Is corrected. Conversely, when the pressure of the pure water in the pure water supply path 2 decreases, the flow rate of the chemical solution introduced into the pure water increases. Therefore, the pure water pressure fluctuation feedback unit 60A causes the chemical flow rate operation voltage Vd1 to decrease the chemical solution flow rate. Is corrected. The corrected chemical liquid flow rate operation voltage Vd1 ′ is converted into a pilot pressure by the electropneumatic converter 20 and provided to the chemical liquid flow rate control valve 21. as a result,
When the pure water pressure in the pure water supply path 2 becomes higher than the pure water pressure reference value P ₀ , the opening of the chemical liquid flow control valve 21 increases in accordance with the pressure fluctuation, and conversely, the pure water pressure increases. When the pressure becomes lower than the pure water reference value P ₀ , the opening degree of the chemical liquid flow control valve 21 decreases according to the pressure fluctuation. As described above, since the opening degree of the chemical liquid flow control valve 21 is operated according to the fluctuation of the pure water pressure in the pure water supply path 2, a constant amount of the chemical liquid is always supplied irrespective of the fluctuation of the pure water pressure. Introduced inside.

A7: Modifications (1) The chemical liquid flow control valve 21 described in this embodiment is replaced by the chemical liquid introduction valve 9, the chemical liquid supply valve 10, and the chemical liquid of each of the above-described second to fifth embodiments. It is also possible to use in place of the pressure regulator 19. In this case, the conversion formulas of the flow rate-voltage conversion units 47 and 85 and the pressure-voltage conversion unit 62 shown in FIGS. 6, 8, and 10 may be changed in the same manner as described in the sixth embodiment.

(2) In the first to fifth embodiments, as shown in FIG. 2, the chemical solution introduction valve 9 is connected to the introduction valve connecting pipe 12 interposed in the pure water supply path 2, and In the embodiment, as shown in FIG. 14, the chemical liquid flow rate control valve 21 is connected to the introduction valve connecting pipe 12 similarly. However, the chemical liquid introduction valve 9 and the chemical liquid flow control valve 21 do not necessarily need to be directly connected to the pure water supply path 2, and can be provided at an appropriate position in the chemical liquid supply path 11.

[0154]

As apparent from the above description, the present invention has the following effects. The invention described in claim 1 is
By adjusting the chemical pressure in the chemical liquid supply path according to the fluctuation of the pure water pressure in the pure water supply path, the differential pressure between the chemical liquid pressure on the inlet side of the chemical liquid introduction valve and the pure water pressure on the outlet side is adjusted. Keep constant. Therefore, according to the present invention, even when the pure water pressure fluctuates, the amount of the chemical solution introduced into the pure water is always constant, so that it is possible to suppress the concentration fluctuation of the processing solution caused by the fluctuation of the pure water pressure. it can.

According to the second aspect of the present invention, the flow rate of the chemical in the chemical supply path is adjusted by operating the valve opening of the chemical flow control valve in accordance with the fluctuation of the pure water pressure in the pure water supply path. . Therefore, according to the present invention, even when the pure water pressure fluctuates, the amount of the chemical solution introduced into the pure water is always constant, so that it is possible to suppress the concentration fluctuation of the processing solution caused by the fluctuation of the pure water pressure. it can.

The invention according to claims 3 and 4 is
The pure water pressure in the pure water supply path is actually measured by the pure water pressure detecting means, and the pressure fluctuation value of the pure water is obtained from the actually measured pure water pressure value and the pure water pressure reference value. Therefore, according to the third aspect of the invention, the chemical solution pressure is adjusted by the feedback of the pure water pressure fluctuation, and according to the fourth aspect, the chemical solution flow rate is adjusted by the feedback of the pure water pressure variation. Can be performed with high accuracy.

According to the fifth and sixth aspects of the present invention, since the present pure water pressure value is obtained by calculation,
There is no need to provide a sensor for measuring the pure water pressure.

According to the seventh aspect of the present invention, the chemical pressure in the chemical supply path is adjusted so as to cancel the deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. In addition to the effects of the invention described in 1, the fluctuation in the concentration of the processing liquid can be suppressed even when the chemical liquid introduction valve is thermally deformed.

According to the eighth aspect of the present invention, the flow rate of the chemical in the chemical supply path is adjusted so as to cancel the deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. In addition to the effect of the invention described in 2, the fluctuation in the concentration of the processing liquid can be suppressed even when the chemical liquid flow rate control valve is thermally deformed.

According to the ninth aspect of the present invention, when the chemical solution pressure or the chemical solution flow rate is adjusted based on the concentration deviation of the processing solution, the current concentration of the processing solution is obtained by calculation. It is not necessary to provide a sensor for measuring the concentration of the compound.

According to the tenth aspect of the present invention, the pure water pressure in the pure water supply passage is adjusted so as to cancel the deviation between the pure water flow target value and the pure water flow present value. In addition to the effects of the seventh and eighth aspects of the present invention, even when the flow path resistance of the pure water supply path changes, it is possible to suppress fluctuations in the concentration of the processing liquid.

According to the eleventh aspect of the present invention, the target value of the flow rate of the chemical solution and the target value of the pure water flow rate of the pure water are set by changing over time, so that the degree of freedom of control of the substrate processing apparatus is improved. Can be higher.

According to the twelfth aspect of the present invention, in the initial stage of replacing the processing liquid in the substrate processing section, the target value of the chemical flow rate of the chemical and the target value of the pure water flow rate of the pure water are both set large.
Since the target value of each flow rate is reduced at a stage where the replacement of the processing liquid has progressed to some extent, it is possible to reduce the time required for the replacement of the processing liquid in the substrate processing unit.

According to the thirteenth aspect, in the initial stage of the replacement when the supply of the processing liquid is started, the ratio of the flow rate of the chemical liquid to the flow rate of the pure water is increased, and the processing liquid having a high concentration is supplied to the substrate processing unit. When the average concentration of the processing liquid in the substrate processing unit has increased to some extent, the flow rate of the chemical solution is reduced, and the processing liquid having a predetermined concentration is supplied to the substrate processing unit. And the processing solution in the substrate processing section can quickly reach the target value.

According to the fourteenth aspect, similar to the seventh aspect, in addition to the effect of the first aspect, it is also possible that the chemical introduction valve is thermally deformed. Even in such a case, it is possible to suppress the concentration fluctuation of the processing solution.

According to the fifteenth aspect, similar to the eighth aspect, in addition to the effect of the second aspect, it is also possible that the chemical liquid flow rate control valve is thermally deformed. Even in such a case, the concentration fluctuation of the processing liquid can be suppressed.

According to the sixteenth aspect, similarly to the ninth aspect, there is no need to provide a sensor for measuring the concentration of the processing solution.

According to the seventeenth aspect, similarly to the tenth aspect, even when the flow path resistance of the pure water supply path changes, the fluctuation in the concentration of the processing liquid can be suppressed. Can also.

According to the eighteenth aspect, the target value of the concentration of the processing liquid and the target value of the pure water flow rate of the pure water are set by changing over time, so that the degree of freedom of control of the substrate processing apparatus is improved. Can be higher.

According to the nineteenth aspect of the present invention, while the target concentration is kept constant with time, pure water is used as the average concentration of the processing solution in the substrate processing unit approaches the target concentration. Since the flow rate is reduced, the processing liquid supplied for replacing the processing liquid in the substrate processing unit can be saved.

According to the twentieth aspect, similar to the seventh aspect, in addition to the effect of the first aspect, it is also possible that the chemical introduction valve is thermally deformed. Even in such a case, it is possible to suppress the concentration fluctuation of the processing solution.

According to the twenty-first aspect, similar to the eighth aspect, in addition to the effect of the second aspect, it is also possible that the chemical liquid flow rate control valve is thermally deformed. Even in such a case, the concentration fluctuation of the processing liquid can be suppressed.

According to the twenty-second aspect, similarly to the ninth aspect, there is no need to provide a sensor for measuring the concentration of the processing solution.

According to the twenty-third aspect, as in the tenth aspect, even when the flow path resistance of the pure water supply path changes, the fluctuation in the concentration of the processing liquid can be suppressed. Can also.

According to the twenty-fourth aspect, the target value of the concentration of the processing liquid and the target value of the chemical flow rate of the chemical liquid are set by changing over time, so that the degree of freedom of control of the substrate processing apparatus is increased. can do.

According to the twenty-fifth aspect of the invention, the target value of the chemical solution flow rate is set to be constant over time, while the target value of the concentration of the processing solution is set high in the initial stage of replacement of the processing solution in the substrate processing section. Then, when the average concentration of the processing liquid in the substrate processing unit has increased to some extent, the target concentration value of the processing liquid is returned to a desired target value. The rise of the average concentration of the liquid is fast, and the processing liquid in the substrate processing section can quickly reach the target value. Further, in the present invention, when changing the concentration of the processing solution, it is not necessary to operate the chemical solution flow rate (as a result, the pure water flow rate is operated), so that the trouble of the chemical solution supply system caused by the operation of the chemical solution flow rate occurs. Can also be suppressed.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a substrate processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a chemical liquid introduction valve.

FIG. 3 is a block diagram functionally showing a control system of the first embodiment.

FIG. 4 is a diagram illustrating an example of a change pattern of a target value according to the first embodiment.

FIG. 5 is a diagram showing another example of the change pattern of the target value in the first embodiment.

FIG. 6 is a block diagram functionally showing a control system according to a second embodiment.

FIG. 7 is a diagram illustrating an example of a change pattern of a target value according to the second embodiment.

FIG. 8 is a block diagram functionally showing a control system according to a third embodiment.

FIG. 9 is a diagram illustrating an example of a change pattern of a target value according to the third embodiment.

FIG. 10 is a block diagram functionally showing a control system according to a fourth embodiment.

FIG. 11 is a block diagram functionally showing a control system according to a fifth embodiment.

FIG. 12 is a diagram illustrating an example of a change pattern of a target value according to the fifth embodiment.

FIG. 13 is a diagram illustrating a schematic configuration of a substrate processing apparatus according to a sixth embodiment.

FIG. 14 is a sectional view showing a structure of a chemical liquid flow control valve.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate processing tank 2 ... Pure water supply path 3 ... Pure water pressure regulator 4 ... Pure water flow sensor 5 ... Chemical liquid mixing part 6 ... Electro-pneumatic converter 7 ... Pure water pressure sensor 8 ... Pure water supply valve 9 ... Chemical liquid Introducing valve 10 ... Chemical liquid supply valve 11 ... Chemical liquid supply path 13 ... Chemical liquid tank 14 ... Gas supply path 15 ... Gas pressure regulator 16 ... Electro-pneumatic converter 18 ... Chemical liquid flow rate sensor 19 ... Chemical liquid pressure regulator 20 ... Electro-pneumatic converter 21 ... Chemical solution flow control valve 30A-30E ... Target value setting unit 31 ... Variable designation unit 32 ... Target value output unit 40A-40C ... Chemical solution concentration feedback control unit 41 ... Concentration target value calculation unit 42 ... Subtractor 43 ... PII ² D Operation unit 44 Switch 45 Adder 46 Concentration-flow rate conversion unit 47 Flow rate-voltage conversion unit 50 Current concentration value calculation unit 60A, 60B Pure water pressure fluctuation feedback unit 61 Subtractor 62 Pressure-voltage conversion unit Part 63 ... adder 64 Pure water pressure current value calculation unit 70: Pure water flow rate feedback control unit 71: Subtractor 72 ... PID calculation unit 73: Switch 74: Adder 75: Flow rate-voltage conversion unit 80: Chemical liquid flow rate feedback control unit 81: Subtractor 82 ... PII ² D calculation unit 83 ... switch 84 ... adder 85 ... flow-voltage conversion unit 90 ... pure water flow current value calculation unit a1 ... chemical liquid flow target value b1 ... chemical liquid flow current value a2 ... pure water flow target value b2 ... Pure water flow rate current value a3 ... Treatment liquid concentration target value b3 ... Treatment liquid concentration current value c1 ... Chemical liquid flow rate deviation d1 ... Chemical liquid flow rate operation quantity c2 ... Pure water flow rate deviation d2 ... Pure water flow rate operation quantity c3 ... the concentration operation amount of density deviation d3 ... treatment liquid Vd1 ... chemical flow operating voltage Vd1 '... corrected chemical flow operating voltage Vd2 ... pure water flow rate operating voltage e2 ... pure water pressure current value P ₀ ... pure water pressure reference value

Claims (25)

[Claims] 1. A substrate processing apparatus for performing a surface treatment of a substrate with a processing liquid obtained by mixing pure water and a chemical solution, wherein the substrate processing unit performs a surface processing of the substrate with a processing liquid; A pure water supply path connected between the section and the pure water supply source; a chemical liquid tank having a closed structure for storing a chemical liquid; a chemical liquid supply path having one end introduced into the chemical liquid in the chemical liquid tank; A chemical pressure feeding means for feeding a chemical solution in a tank to the chemical solution supply path, an inlet side connected to the other end of the chemical solution supply path, an outlet side connected to the pure water supply path, a chemical pressure on the inlet side, and pure water on the outlet side. A chemical solution introduction valve for introducing a chemical solution having a flow rate corresponding to a pressure difference from the pressure into the pure water supply path, and the chemical solution supply based on a chemical solution flow rate operation amount set in relation to a treatment solution concentration target value. A chemical solution pressure regulator for adjusting the chemical solution pressure in the channel; and pure water in the pure water supply channel. The current pressure value is obtained, and when the current pure water pressure value is higher than a predetermined pure water pressure reference value, the chemical liquid pressure controller corrects the chemical liquid flow rate operation amount in a direction to increase the chemical liquid pressure. When the pure water pressure current value becomes lower than the pure water pressure reference value, the pure water pressure fluctuation feedback to be corrected to the chemical solution pressure regulator by correcting the chemical solution flow amount in the direction of decreasing the chemical solution pressure. And a means for processing the substrate. 2. A substrate processing apparatus for performing a surface treatment of a substrate with a processing liquid obtained by mixing pure water and a chemical solution, wherein the substrate processing unit performs a surface processing of the substrate with the processing liquid; A pure water supply path connected between the section and the pure water supply source; a chemical solution tank having a sealed structure for storing a chemical solution; one end being introduced into the chemical solution in the chemical solution tank, and the other end being the pure water supply A chemical solution supply path connected in the middle of the path, a chemical solution pumping means for sending a chemical solution in the chemical solution tank to the chemical solution supply channel, and a chemical solution flow rate operation amount set in relation to a target concentration of the processing solution. By controlling the opening degree of the valve, a chemical liquid flow rate adjusting valve for adjusting the chemical liquid flow rate in the chemical liquid supply path, a pure water pressure current value in the pure water supply path is obtained, and the pure water pressure current value is determined in advance. If the pressure becomes higher than the specified pure water pressure reference value, increase the chemical flow rate. The flow rate of the chemical liquid is corrected in the direction to be applied to the chemical flow rate control valve, and when the current pure water pressure value is lower than the reference value of the pure water pressure, the flow rate of the chemical liquid flow is decreased in the direction of decreasing the flow rate of the chemical liquid. And a pure water pressure fluctuation feedback means for correcting the pressure and giving the corrected pressure to the chemical liquid flow rate control valve. 3. The pure water pressure fluctuation feedback means according to claim 1, wherein the pure water pressure fluctuation feedback means comprises: a pure water pressure detecting means for actually measuring a current pure water pressure value in the pure water supply path; Pure water pressure fluctuation value calculating means for obtaining a pressure fluctuation value of the pure water pressure current value by comparing the current water pressure value with a predetermined pure water pressure reference value; A pure water pressure fluctuation value adding means for adding to the chemical liquid flow rate operation amount and giving to the chemical liquid pressure regulator. 4. The apparatus according to claim 2, wherein the pure water pressure fluctuation feedback means comprises: a pure water pressure detecting means for actually measuring a current pure water pressure value in the pure water supply path; Pure water pressure fluctuation value calculating means for obtaining a pressure fluctuation value of the pure water pressure current value by comparing the current water pressure value with a predetermined pure water pressure reference value; A pure water pressure fluctuation value adding means for adding the chemical liquid flow operation amount to the chemical liquid flow control valve and adding the same to the chemical liquid flow control valve. 5. The apparatus according to claim 1, wherein the pure water pressure fluctuation feedback means calculates a pure water pressure current value based on a pure water flow present value in the pure water supply path by calculation. Calculating means, pure water pressure fluctuation value calculating means for calculating a pressure fluctuation value of the pure water pressure current value by comparing the calculated pure water pressure current value with a predetermined pure water pressure reference value, A pure water pressure fluctuation value adding unit that adds the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and provides the chemical liquid pressure regulator with the pure water pressure fluctuation value. 6. The apparatus according to claim 2, wherein the pure water pressure fluctuation feedback means calculates a pure water pressure current value based on a pure water flow present value in the pure water supply path by calculation. Calculating means, pure water pressure fluctuation value calculating means for calculating a pressure fluctuation value of the pure water pressure current value by comparing the calculated pure water pressure current value with a predetermined pure water pressure reference value, A pure water pressure fluctuation value adding unit that adds the pure water pressure fluctuation value to the chemical liquid flow rate operation amount and gives the pure water pressure fluctuation value to the chemical liquid flow rate control valve. 7. The apparatus according to claim 1, wherein the apparatus further comprises: setting a target value of a chemical solution flow rate of the chemical solution flowing through the chemical solution supply path and a target value of the pure water flow rate of pure water flowing through the pure water supply path. A target value setting means for setting a concentration deviation between the target concentration of the treatment liquid and the current concentration of the treatment liquid, and adjusting a chemical flow rate operation amount given to the chemical pressure regulator so as to cancel the concentration deviation. A chemical solution concentration feedback control unit, wherein the chemical solution concentration feedback control unit calculates the concentration target value of the treatment liquid based on the chemical solution flow target value and the pure water flow target value provided from the target value setting unit. Target value calculating means; density deviation calculating means for calculating a density deviation between the target concentration of the processing liquid provided from the concentration target value calculating means and the current concentration of the processing liquid; processing for canceling the density deviation Liquid concentration A substrate processing apparatus, comprising: a concentration manipulated variable calculating means for calculating a manipulated variable; and a manipulated variable converting means for converting the calculated concentration manipulated variable into a chemical solution flow manipulated variable. 8. The apparatus according to claim 2, wherein the apparatus further comprises: a target value of a chemical liquid flow rate of the chemical flowing through the chemical liquid supply path and a target pure water flow rate of pure water flowing through the pure water supply path. A target value setting means for setting, a concentration deviation between the target concentration of the treatment liquid and the current concentration of the treatment liquid, and adjusting a chemical flow rate operation amount given to the chemical flow control valve so as to cancel the concentration deviation. A chemical solution concentration feedback control unit, wherein the chemical solution concentration feedback control unit calculates the concentration target value of the treatment liquid based on the chemical solution flow target value and the pure water flow target value provided from the target value setting unit. Target value calculating means; density deviation calculating means for calculating a density deviation between the target concentration of the processing liquid provided from the concentration target value calculating means and the current concentration of the processing liquid; processing for canceling the density deviation Liquid concentration A substrate processing apparatus, comprising: a concentration manipulated variable calculating means for calculating a manipulated variable; and a manipulated variable converting means for converting the calculated concentration manipulated variable into a chemical solution flow manipulated variable. 9. An apparatus according to claim 7, wherein said apparatus further comprises a current concentration value calculating means for calculating a current concentration value of the processing liquid based on the current value of the chemical solution flow rate and the current value of the pure water flow rate. A substrate processing apparatus for providing the calculated current value of the concentration of the processing liquid to the concentration deviation calculating means. 10. The apparatus according to claim 7, wherein the apparatus is further provided in the pure water supply path upstream of a position where a chemical solution is introduced into the pure water supply path, A pure water pressure regulator that adjusts the pure water pressure in the pure water supply path based on the flow rate operation amount, and a pure water flow target value given from the target value setting means,
A pure water flow rate feedback control means for obtaining a deviation from the pure water flow current value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and giving the pure water flow manipulated variable to the pure water pressure regulator. A substrate processing apparatus comprising: 11. The substrate processing apparatus according to claim 10, wherein the target value setting unit sets a chemical liquid flow target value and a pure water flow target value that change with time. 12. The apparatus according to claim 11, wherein the target value setting unit starts supplying the processing liquid into the substrate processing unit filled with pure water and starts processing liquid in the substrate processing unit. Until it is replaced with
A substrate processing apparatus for setting respective initial target values of a chemical solution flow target value and a pure water flow target value higher than the respective subsequent target values. 13. The apparatus according to claim 11, wherein the target value setting unit starts supplying the processing liquid into the substrate processing unit filled with pure water and starts processing liquid in the substrate processing unit. Until it is replaced with
A substrate processing apparatus that sets an initial target value of a chemical solution flow target value higher than a subsequent chemical solution flow target value, while setting the pure water flow target value constant. 14. The apparatus according to claim 1, wherein the apparatus further comprises a target value setting means for setting a target value of the concentration of the processing liquid and a target value of the pure water flow rate of the pure water flowing through the pure water supply path. A chemical concentration feedback control means for determining a concentration deviation between the concentration target value of the processing solution and the current concentration of the processing solution, and adjusting a chemical flow rate operation amount given to the chemical solution pressure regulator so as to cancel the concentration deviation; Wherein the chemical concentration feedback control means comprises: a concentration deviation calculating means for calculating a concentration deviation between a target concentration of the processing liquid given from the target value setting means and a current concentration of the processing liquid; and A substrate processing apparatus, comprising: a concentration manipulated variable calculation unit that computes a concentration manipulated volume of a processing solution that cancels out; 15. The apparatus according to claim 2, wherein the apparatus further comprises a target value setting means for setting a target value of the concentration of the treatment liquid and a target value of a pure water flow rate of the pure water flowing through the pure water supply path. A concentration deviation between the target concentration of the treatment liquid and the current concentration of the treatment liquid, and a chemical concentration feedback control means for adjusting a chemical flow rate operation amount given to the chemical flow control valve so as to cancel the concentration deviation; Wherein the chemical concentration feedback control means comprises: a concentration deviation calculating means for calculating a concentration deviation between a target concentration of the processing liquid given from the target value setting means and a current concentration of the processing liquid; and A substrate processing apparatus, comprising: a concentration manipulated variable calculation unit that computes a concentration manipulated volume of a processing solution that cancels out; 16. An apparatus according to claim 14, further comprising: a current concentration value calculating means for calculating a current concentration value of the processing liquid based on the current value of the chemical liquid flow and the current value of the pure water flow. A substrate processing apparatus for providing the calculated current value of the concentration of the processing liquid to the concentration deviation calculating means. 17. The apparatus according to claim 14, further comprising a pure water supply passage disposed upstream of a position at which a chemical solution is introduced into the pure water supply passage. A pure water pressure regulator that adjusts the pure water pressure in the pure water supply path based on the flow rate operation amount, and a pure water flow target value given from the target value setting means,
A pure water flow rate feedback control means for obtaining a deviation from the pure water flow current value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and giving the pure water flow manipulated variable to the pure water pressure regulator. A substrate processing apparatus comprising: 18. The substrate processing apparatus according to claim 17, wherein the target value setting means sets a target concentration of the processing liquid and a target value of the pure water flow rate, each of which changes with time. 19. The apparatus according to claim 18, wherein the target value setting unit sets the processing liquid in the substrate processing unit from a point in time when the supply of the processing liquid into the substrate processing unit filled with pure water is started. Until it is replaced with
A substrate processing apparatus that sets a target concentration of a processing solution to a constant value, while decreasing the pure water flow target value from its initial target value as the replacement with the processing solution proceeds. 20. The apparatus according to claim 1, wherein the apparatus further comprises: a target value setting unit configured to set a target concentration of the treatment liquid and a target value of a chemical liquid flow rate of the chemical flowing through the chemical liquid supply path. A solution concentration feedback control means for adjusting a solution flow rate operation amount given to the solution pressure regulator so as to obtain a concentration deviation between the concentration target value of the solution and the current concentration of the processing solution, and to cancel the concentration deviation; The chemical concentration feedback control means, based on the concentration target value of the treatment liquid and the chemical solution flow target value given from the target value setting means, a pure water flow target value calculation means for calculating a pure water pure water flow target value Density deviation calculating means for calculating a concentration deviation between the target concentration of the processing liquid given from the target value setting means and the current concentration of the processing liquid; and a concentration manipulated variable of the processing liquid for canceling the concentration deviation. Calculate A substrate processing apparatus, comprising: a concentration manipulated variable calculation unit; and a manipulated variable conversion unit configured to convert the calculated concentration manipulated variable into a chemical solution flow manipulated variable. 21. The apparatus according to claim 2, wherein the apparatus further comprises: target value setting means for setting a target concentration of the processing liquid and a target value of a chemical flow rate of the chemical flowing through the chemical supply path; A chemical concentration feedback control means for adjusting a chemical flow rate operation amount given to the chemical flow rate control valve so as to obtain a concentration deviation between the concentration target value of the liquid and the current concentration value of the processing liquid, and to cancel the concentration deviation, The chemical concentration feedback control means, based on the concentration target value of the treatment liquid and the chemical solution flow target value given from the target value setting means, a pure water flow target value calculation means for calculating a pure water pure water flow target value Density deviation calculating means for calculating a concentration deviation between the target concentration of the processing liquid given from the target value setting means and the current concentration of the processing liquid; and a concentration manipulated variable of the processing liquid for canceling the concentration deviation. Calculate A substrate processing apparatus, comprising: a concentration manipulated variable calculation unit; and a manipulated variable conversion unit configured to convert the calculated concentration manipulated variable into a chemical solution flow manipulated variable. 22. The apparatus according to claim 20, wherein the apparatus further comprises a current concentration value calculating means for calculating a current concentration value of the processing liquid based on the current value of the chemical liquid flow and the current value of the pure water flow. A substrate processing apparatus for providing the calculated current value of the concentration of the processing liquid to the concentration deviation calculating means. 23. The apparatus according to claim 20, wherein the apparatus is further provided in the pure water supply path upstream of a position where a chemical solution is introduced into the pure water supply path, A pure water pressure regulator that adjusts the pure water pressure in the pure water supply path based on the flow manipulated variable; a pure water flow target value provided from the pure water flow target value calculation means; and a pure water flow current value And a pure water flow rate feedback control means for giving the pure water flow rate manipulated variable to the pure water pressure regulator. apparatus. 24. The substrate processing apparatus according to claim 23, wherein said target value setting means sets a target concentration of the processing liquid and a target value of the chemical flow rate, each of which changes with time. 25. The apparatus according to claim 24, wherein the target value setting unit sets the processing liquid in the substrate processing unit from a point in time when the supply of the processing liquid into the substrate processing unit filled with pure water is started. Until it is replaced with
A substrate processing apparatus for setting an initial target value of a processing solution concentration target value larger than a subsequent processing solution concentration target value, while setting a chemical solution flow rate target value constant.