JPH10326764A - 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 variation of the introducing amount of a chemical to pure water. 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 chemical concentration feedback control section 40A finds the concentration deviation between the target concentration value of a treating liquid and the present concentration value of the treating liquid calculated by means of a present concentration value(calculating section 50, and adjusts the chemical supply control value Vd1 given to a chemical pressure regulator 19 so as to offset the concentration deviation. Therefore, even when the flow rate characteristic of the valve 9 changes, the concentration fluctuation of the treating liquid is suppressed by constantly maintaining the introducing amount of the chemical to the pure water.

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, the heated chemical liquid may flow through the chemical liquid introduction valve, or the heated pure water may flow through the pure water supply path on the outlet side of the chemical liquid introduction valve. As a result, the chemical introduction valve may be thermally deformed. In particular, when the chemical liquid introduction valve is formed of a synthetic resin in consideration of chemical resistance, thermal deformation increases. If the chemical introduction valve is deformed, its flow characteristics will change, so even if the differential pressure between the chemical pressure on the inlet side of the chemical introduction valve and the pure water pressure on the outlet side is kept constant, the chemical into pure water , The concentration of the processing solution fluctuates as a result.

The present invention has been made in view of such circumstances, and provides a substrate processing apparatus capable of suppressing a change in the concentration of a processing solution caused by a change in the amount of a chemical solution introduced into pure water. The main purpose is to

[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 manipulated variable set in relation to the concentration target value of the liquid, and a chemical liquid flow rate target value of the chemical flowing through the chemical supply path And a target value setting means for setting a pure water flow rate target value of pure water to be circulated through the pure water supply path, and a concentration deviation between a target concentration of the processing liquid and a current concentration of the processing liquid, and this concentration deviation is calculated. A chemical solution concentration feedback control means for adjusting and setting a chemical solution flow rate operation amount given to the chemical solution pressure regulator so as to cancel, the chemical solution concentration feedback control means comprising a chemical solution flow rate target provided from the target value setting means. Value based on the target value and the pure water flow rate target value. 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; It is characterized in that it includes a concentration manipulated variable calculating means for calculating a concentration manipulated variable of the processing liquid that cancels the concentration deviation, and an operation variable converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable.

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 controlling the opening degree of the valve based on the chemical liquid flow operation amount, a chemical liquid flow control valve for adjusting the chemical liquid flow rate in the chemical liquid supply path, a chemical liquid flow target value of the chemical liquid flowing through the chemical liquid supply path, and the pure liquid flow rate. Set the target value of pure water flow rate for pure water flowing through the water supply path. A target 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 and setting a chemical liquid flow operation amount given to the chemical liquid flow control valve so as to cancel the concentration deviation. Chemical solution concentration feedback control means, wherein the chemical solution concentration feedback control device calculates a treatment solution concentration target value based on the chemical solution flow target value and the pure water flow target value provided from the target value setting device. A density target value calculating means, a density deviation calculating means for obtaining a density deviation between the processing liquid concentration target value given from the concentration target value calculating means and a current concentration of the processing liquid, and a method for canceling the density deviation. It is characterized in that it comprises a concentration manipulated variable calculating means for calculating the concentration manipulated variable of the treatment liquid, and an operation amount converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable.

According to a third aspect of the present invention, in the apparatus according to the first or second aspect, the apparatus further calculates a current concentration 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 fourth aspect of the present invention, in the device according to the first or second aspect, the apparatus further comprises a 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 pure water flow operation amount; a pure water flow target value provided from the target value setting means; A pure water flow rate feedback control means for calculating a deviation from the current water flow value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and providing the pure water flow manipulated variable to the pure water pressure regulator. Is provided.

According to a fifth aspect of the present invention, in the device according to the first or second aspect, the target value setting means sets a chemical liquid flow target value and a pure water flow target value, each of which changes with time. Is what you do.

According to a sixth aspect of the present invention, in the apparatus according to the fifth aspect, the apparatus further includes a water supply passage disposed upstream of a position where the chemical solution is introduced into the pure water supply passage. A pure water pressure regulator for adjusting a pure water pressure in the pure water supply path based on a pure water flow operation amount; a pure water flow target value provided from the target value setting means; A pure water flow rate feedback control means for obtaining a deviation from the present value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and providing the pure water flow manipulated variable to the pure water pressure regulator. .

According to a seventh aspect of the present invention, in the apparatus according to the fifth or sixth aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. From the time until the inside of the substrate processing unit is replaced with the processing liquid, the initial target values of the chemical solution flow target value and the pure water flow target value are set higher than the respective target values thereafter. .

According to an eighth aspect of the present invention, in the device according to the fifth or sixth aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. From, until the inside of the substrate processing unit is replaced by the processing liquid, while setting the initial target value of the chemical liquid flow target value higher than the subsequent chemical liquid flow target value,
The target value of the pure water flow rate is set constant.

According to a ninth aspect of the present invention, there is provided a substrate processing apparatus for performing a surface treatment of a substrate with a processing solution obtained by mixing pure water and a chemical solution, wherein the substrate is subjected to a surface treatment with the processing solution. A processing unit, a pure water supply path connected between the substrate processing unit and a pure water supply source, a chemical tank having a pressure-resistant sealed structure for storing a chemical, and one end introduced into the chemical in the chemical tank. A chemical solution supply path, a chemical solution pumping means for sending the chemical solution in the solution tank to the chemical solution supply channel, an inlet side connected to the other end of the chemical solution supply path, an outlet side connected to the pure water supply path, and a chemical solution on the inlet side. Pressure, a chemical introduction valve for introducing a chemical at a flow rate according to the differential pressure between the pure water pressure on the outlet side into the pure water supply path, and a chemical flow rate operation amount determined in relation to a target concentration of the treatment liquid Based on the chemical solution pressure regulator for adjusting the chemical solution pressure in the chemical solution supply path, A target value setting means for setting a target concentration of the treatment liquid and a target value of the pure water flow rate of the pure water flowing through the pure water supply path; and 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 and setting a chemical flow rate operation amount given to the chemical liquid pressure regulator so as to cancel the concentration deviation, and wherein the chemical concentration feedback control means comprises the target value setting means. A density deviation calculating means for calculating a density deviation between a target concentration of the processing liquid given from the above and a current concentration of the processing liquid, and a density operation amount calculation for calculating a density operation amount of the processing liquid to cancel the concentration deviation Means, and an operation amount conversion means for converting the calculated concentration operation amount into a chemical solution flow amount operation amount.

According to a tenth aspect of the present invention, there is provided a substrate processing apparatus for performing a surface treatment of a substrate with a processing solution obtained by mixing pure water and a chemical solution, wherein the substrate is provided with a processing solution. A processing unit, a pure water supply path connected between the substrate processing unit and a pure water supply source, a chemical tank having a pressure-resistant sealed structure for storing a chemical, and one end introduced into the chemical in the chemical tank. The other end is determined in relation to a chemical supply path connected in the middle of the pure water supply path, a chemical liquid pumping means for sending the chemical in the chemical liquid tank to the chemical supply path, and a target concentration of the processing liquid. By controlling the opening of the valve based on the amount of operation of the chemical liquid flow, a chemical liquid flow control valve that adjusts the chemical liquid flow rate in the chemical liquid supply path, a target concentration of the processing liquid, and a pure liquid flowing through the pure water supply path. A target value setting means for setting a pure water flow rate target value of water; Chemical concentration feedback control means for determining the concentration deviation between the concentration target value of the treatment liquid and the current concentration of the treatment liquid, and adjusting and setting the amount of operation of the chemical flow rate given to the chemical flow control valve so as to cancel the concentration deviation. Wherein the chemical liquid 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 manipulated variable converting means for converting the calculated manipulated variable concentration into a chemical liquid flow manipulated variable.

According to an eleventh aspect of the present invention, in the apparatus according to the ninth or tenth aspect, the apparatus further calculates a current concentration value 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 present concentration value of the processing solution is given to the concentration deviation calculating means.

According to a twelfth aspect of the present invention, in the apparatus according to the ninth or tenth aspect, the apparatus further comprises a 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 pure water flow operation amount; a pure water flow target value provided from the target value setting means; A pure water flow rate feedback control means for calculating a deviation from the current water flow value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and providing the pure water flow manipulated variable to the pure water pressure regulator. Is provided.

According to a thirteenth aspect of the present invention, in the apparatus according to the ninth or tenth aspect, the target value setting means includes:
The target value of the treatment liquid and the target value of the pure water flow rate, which change with time, are set.

According to a fourteenth aspect of the present invention, in the apparatus according to the thirteenth aspect, the apparatus further includes a pure water supply passage upstream of a position where a chemical solution is introduced into the pure water supply passage. A pure water pressure regulator for adjusting a pure water pressure in the pure water supply path based on a pure water flow operation amount; a pure water flow target value provided from the target value setting means; A pure water flow rate feedback control means for obtaining a deviation from the present value, calculating a pure water flow manipulated variable to cancel the pure water flow deviation, and providing the pure water flow manipulated variable to the pure water pressure regulator. .

According to a fifteenth aspect of the present invention, in the apparatus according to the thirteenth or fourteenth aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. From the time until the inside of the substrate processing unit is replaced with the processing liquid, the target concentration of the processing liquid is set to a constant value, and as the replacement with the processing liquid progresses, the pure water flow rate target value is set to the initial target. It should be smaller than the value.

According to a sixteenth aspect of the present invention, there is provided a substrate processing apparatus for performing a surface treatment of a substrate with a processing solution obtained by mixing pure water and a chemical solution, wherein the substrate is provided with a processing solution. A processing unit, a pure water supply path connected between the substrate processing unit and the pure water supply source, a chemical liquid tank having a closed structure for storing a chemical liquid, and one end introduced into the chemical liquid in the chemical liquid tank. A chemical solution supply path, a chemical solution pumping means for sending the chemical solution in the solution tank to the chemical solution supply channel, an inlet side connected to the other end of the chemical solution supply path, an outlet side connected to the pure water supply path, and a chemical solution pressure on the inlet side. And a chemical introduction valve for introducing a chemical at a flow rate corresponding to the pressure difference between the pure water pressure at the outlet side and the pure water supply path, and a chemical liquid flow rate operation amount set in relation to the concentration target value of the treatment liquid. A chemical solution pressure regulator for adjusting the chemical solution pressure in the chemical solution supply path based on A target value setting means for setting a target concentration of the liquid and a target value of the chemical flow rate of the chemical to be circulated through the chemical supply path; and determining a concentration deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. A chemical solution concentration feedback control means for adjusting and setting a chemical solution flow rate operation amount applied to the chemical solution pressure regulator so as to cancel the concentration deviation, wherein the chemical solution concentration feedback control means is provided from the target value setting means. A pure water flow target value calculating means for calculating a pure water pure water flow target value based on the processing liquid concentration target value and the chemical liquid flow target value; and a processing liquid concentration target value given from the target value setting means. A concentration deviation calculating means for calculating a concentration deviation from the current concentration of the processing liquid; a concentration operation amount calculating means for calculating a concentration operation amount of the processing liquid for canceling the concentration deviation; and the calculated concentration operation amount. The chemical flow rate operation It is characterized by comprising a manipulated variable conversion means for converting.

According to a seventeenth aspect of the present invention, there is provided a substrate processing apparatus for performing a surface treatment of a substrate with a processing solution obtained by mixing pure water and a chemical solution, wherein the substrate is provided with a processing solution. 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 of the chemical water supply path connected in the middle of the pure water supply path,
A chemical solution pumping means for sending a chemical solution in the chemical solution tank to the chemical solution supply path; and a valve opening degree based on a chemical solution flow rate operation amount set in relation to a concentration target value of the processing solution, whereby the chemical solution is operated. A chemical liquid flow rate control valve for adjusting the flow rate of the chemical liquid in the supply path, a target value setting means for setting 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; A chemical solution concentration feedback control means for adjusting and setting a chemical solution flow rate operation amount given to the chemical solution flow control valve so as to cancel the concentration deviation between the value and the current concentration of the treatment liquid, 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, , The target value setting A concentration deviation calculating means for calculating a concentration deviation between a target concentration of the processing liquid given from the stage and a current concentration of the processing liquid, and a concentration control amount for calculating a concentration control amount of the processing liquid to cancel the concentration deviation It is characterized by including calculation means and operation amount conversion means for converting the calculated concentration operation amount into a chemical solution flow amount operation amount.

According to an eighteenth aspect of the present invention, in the apparatus according to the sixteenth or seventeenth aspect, the apparatus further calculates a 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 present concentration value of the processing solution is given to the concentration deviation calculating means.

According to a nineteenth aspect of the present invention, in the device according to the sixteenth or seventeenth 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 pure water flow target value calculation means, and a deviation between the pure water flow present value and And a pure water flow rate feedback control means for calculating a pure water flow manipulated variable that cancels the pure water flow deviation, and applying the pure water flow manipulated variable to the pure water pressure regulator.

According to a twentieth aspect of the present invention, in the apparatus according to the sixteenth or seventeenth aspect, the 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. To set.

According to a twenty-first aspect of the present invention, in the apparatus according to the twentieth 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. A pure water pressure regulator that adjusts the pure water pressure in the pure water supply path, based on the pure water flow operation amount, and a pure water flow target value provided from the pure water flow target value calculation 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. And

According to a twenty-second aspect of the present invention, in the apparatus according to the twentieth or twenty-first aspect, the target value setting means starts supplying a processing liquid into the substrate processing unit filled with pure water. From the time 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 set. It is set to be constant.

[0030]

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. As a result, a chemical solution having a flow rate corresponding to the pressure difference between the chemical solution pressure on the inlet side and the pure water pressure on the outlet side of the chemical solution introduction valve is introduced into the pure water. At this time, if the flow rate characteristic changes due to thermal deformation of the chemical liquid introduction valve or the like, the concentration of the processing liquid fluctuates due to a change in the amount of chemical liquid introduced into pure water. The chemical concentration feedback control means suppresses the concentration fluctuation of the processing liquid as follows. First, the target concentration calculating unit calculates the target concentration of the processing liquid based on the chemical liquid flow target value and the pure water flow target value given by the target value 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 a result, the amount of the chemical solution introduced into the pure water is adjusted, and the fluctuation in the concentration of the processing solution is suppressed.

According to the second aspect of the present invention, the opening degree of the chemical liquid flow rate control valve is operated based on the chemical liquid flow rate operation amount set in relation to the processing liquid concentration target value. A predetermined amount of the chemical solution flows in the chemical solution supply path, and is introduced into the pure water in the pure water supply path. At this time, if the flow rate characteristics of the chemical liquid flow control valve undergo thermal deformation or the like, the concentration of the processing liquid fluctuates due to a change in the amount of the chemical liquid introduced into the pure water. The chemical liquid concentration feedback control means suppresses the concentration fluctuation of the processing liquid. Since the operation of the chemical concentration feedback control means is the same as in the case of the first aspect of the present invention,
The description here is omitted. However, in the case of the invention of claim 2, the chemical liquid flow rate operation amount obtained by the chemical liquid concentration feedback control means is given to the chemical liquid flow rate control valve, and the valve opening is operated to directly adjust the chemical liquid flow rate. As a result, the amount of the chemical solution introduced into the pure water is adjusted, and the fluctuation in the concentration of the processing solution is suppressed.

According to a third aspect of the present invention, in the apparatus according to the first or second aspect, the current concentration value calculating means determines the current concentration 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 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 4 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 4 is provided with 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 5 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.

According to the sixth aspect of the present invention, the pure water flow rate feedback control means controls the pure water flow rate operation so as to cancel the deviation between the pure water flow rate target value that changes with time and the pure water flow rate current value. Since the flow rate is adjusted, the pure water flow rate in the pure water supply path can accurately follow the pure water flow rate target value even when the flow path resistance of the pure water supply path changes.

The operation of the invention described in claim 7 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 chemical flow rate of the chemical and the target value of the pure water flow rate of the pure water are small, the flow rate of the pure water supplied to the substrate processing unit for replacement or the flow rate of the processing liquid becomes small, Becomes longer with the replacement of a new processing solution, and the processing efficiency decreases. Conversely, setting the pure water flow target value of the chemical 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 7 is characterized in that, in the initial stage of replacing the processing liquid in the substrate processing section, the target value of the chemical liquid flow rate and the target value of the pure water flow rate of the pure water are set. Are set to be large, and at the stage where the replacement of the processing liquid has progressed to some extent, the flow rate target values are reduced.

The operation of the invention described in claim 8 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, 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 8 is to increase the ratio of the chemical solution flow rate to the pure water flow rate in the initial stage of the replacement when the supply of the processing solution is started. 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 described in claim 9 is as follows. A ninth aspect of the present invention includes a target value setting unit and a chemical concentration feedback control unit for the same purpose as described in the operation of the first aspect of the present invention. However, in the invention according to claim 9, the target value setting means sets the target concentration of the processing liquid and the 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. Other operations are the same as those of the first aspect of the present invention, and a description thereof will not be repeated.

The operation of the tenth aspect of the present invention is substantially the same as that of the second aspect of the present invention, and the description thereof is omitted. However, in the invention according to claim 10, the target value setting means sets the concentration target value of the treatment liquid and the pure water flow rate target value of pure water, and the concentration deviation calculating means, as in the ninth invention. The concentration deviation between the set processing solution concentration target value and the processing solution concentration current value is determined.

Since the operation of the invention described in claim 11 is the same as the operation of the invention described in claim 3, the description is omitted here.

The operation of the invention described in claim 12 is the same as the operation of the invention described in claim 4, and the description is omitted here.

The operation of the invention according to claim 13 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 14 is the same as the operation of the invention described in claim 6, and therefore the description is omitted here.

The operation of the invention according to claim 15 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 target value of the pure water flow rate 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 15 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 claim 16 is as follows. The invention according to claim 16 is provided with target value setting means and chemical solution concentration feedback control means for the same purpose as described in the operation of the invention according to claim 1. However, in the invention according to claim 16, the target value setting means sets the target concentration of the treatment liquid and the target value of the chemical flow rate of the chemical.
The pure water flow target value calculation means calculates a pure water pure water flow target value based on the set processing liquid concentration target value and the chemical liquid flow target value. 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 first aspect of the present invention, and a description thereof will not be repeated.

The operation of the invention described in claim 17 is substantially the same as the operation of the invention described in claim 2, and the description is omitted here. However, in the tenth aspect, similarly to the sixteenth aspect, the target value setting means sets the target concentration of the treatment liquid and the target value of the chemical flow rate of the chemical liquid. The pure water flow target value calculation means calculates a pure water pure water flow target value based on the set processing liquid concentration target value and the chemical liquid flow target value. 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 operation of the invention described in claim 18 is the same as the operation of the invention described in claim 3, and the description thereof is omitted.

The operation of the invention described in claim 19 is the same as the operation of the invention described in claim 4, and the description is omitted here.

The operation of the twentieth aspect 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 of claim 21 is the same as the operation of the invention of claim 6, except that the pure water flow target value is calculated by the pure water flow target value calculation means. The description here is omitted.

The operation of the invention according to claim 22 is as follows. If the target concentration of the treatment liquid and the target value of the chemical flow rate of the chemical liquid are set to constant values over time, the same disadvantages as described in the operation of the invention of claim 8 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 22, the target value of the chemical liquid flow rate is set to be constant over time, while the target concentration value is set to be high in the initial stage of the 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.

[0057]

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 discharge the excess processing liquid by overflowing. 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: Structure 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 types 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 this 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 in the chemical solution supply path 11 from the chemical solution tank 13 side.
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 target value and a pure water flow 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 liquid concentration feedback control section 40A is 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 unit 50 calculates the current concentration value of the treatment 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 liquid flow sensor 18. b3 is calculated. The current concentration value b3 is provided to the chemical concentration feedback control unit 40A.

[0073] 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 the target value (in the present embodiment, the chemical liquid flow rate target value a1 and the pure water flow rate target value). 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 processing 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 processing solution concentration target value a 3 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 thereby obtain the 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 unit 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 given from the PII ² D calculation unit 43 via the switch 44 to the concentration target value a3 of the treatment liquid given 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 through the pure water supply path 2, the chemical supply valve 10 is opened and the chemical liquid flows through 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 conversion section 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 subtractor 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 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 pure water pressure fluctuation, the above-mentioned 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 calculates the pure water flow rate sensor 4 from 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 path 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 rate-voltage conversion unit 75 calculates the pure water flow rate 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.

This pure water flow operation voltage Vd 2 is given 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 control unit 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 actual 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, 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 liquid 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) If 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 pure water flow rate target value a2.
Alternatively, the pure water flow rate current value b2 obtained by actual measurement may be used.

(3) If the pressure fluctuation of the pure water in the pure water supply path 2 does not cause any particular problem, it is not necessary to provide the pure water pressure fluctuation feedback section 60A. This is the same in the following embodiments.

(4) If the fluctuation of the flow rate of pure water in the pure water supply path 2 does not cause any particular problem, it is not necessary to provide the pure water flow rate feedback control unit 70. This is the same in the following embodiments.

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 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.

B4: Schematic Configuration of Control System FIG. 6 shows the configuration of the control system of the present 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 target concentration a3 of the processing liquid, 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) (6) where a1 is the target value of the chemical flow rate [cc / min] a2 is the target value of the pure water flow rate [liter / min] a3 is the target concentration of the processing liquid Value [%] 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 unit 48 is given to the concentration-flow rate conversion unit 46 and the pure water flow feedback control unit 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. Instead of the pure water flow target value a2, the pure water flow current value b
2 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 processing solution concentration target value a3 and the chemical solution flow rate target value a1 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: Configuration of Fourth Embodiment Apparatus FIG. 10 shows a schematic configuration of a substrate processing apparatus according to this embodiment. In FIG. 10, the components indicated by the same reference numerals as those in FIG. 1 have the same configuration as that of 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 solution pressure is controlled by the chemical solution pressure regulator 19 provided in the chemical solution supply passage 11 so that the chemical solution at a constant flow rate is supplied to the chemical solution introduction valve 9.
And introduced into the pure water supply path 2. On the other hand, the apparatus of the fourth embodiment replaces the chemical introduction valve 9, the chemical supply valve 10, and the chemical pressure regulator 19 of the first embodiment with
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 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. 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.

D4: 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.

D5: 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 rate 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 the concentration deviation of the processing liquid, and converts this to the chemical flow rate operation voltage Vd1 corresponding to the chemical flow rate control valve 21.
Convert to and set. The chemical liquid flow rate operation voltage Vd1 is supplied to the electropneumatic converter 20 via the pure water pressure fluctuation feedback unit 60A. The electropneumatic converter 20 outputs a pilot pressure according to the chemical flow rate operation voltage Vd1 to the chemical flow control valve 21.
As a result, the opening degree of the chemical liquid flow control valve 21 is operated, and the chemical liquid flow rate in the chemical liquid supply path 11 is adjusted. Therefore, for example, the flow of the heated chemical through the chemical flow control valve 21 causes the chemical flow control valve 21 to undergo thermal deformation. As a result, the flow rate of the chemical introduced into the pure water changes, and Even if the concentration of the chemical liquid fluctuates, the chemical liquid flow rate is adjusted by operating the valve opening of the chemical liquid flow control valve 21 as described above, so that the concentration fluctuation of the processing liquid can be suppressed quickly.

Further, in the present embodiment, the concentration fluctuation of the processing liquid due to the fluctuation of the pure water pressure in the pure water supply path 2 is suppressed by the pure water pressure fluctuation feedback section 60A as follows. The pure water pressure fluctuation feedback unit 60A corrects the chemical liquid flow rate operation voltage Vd1 in a direction to increase the chemical liquid flow rate because the flow rate of the chemical liquid introduced into the pure water decreases as the pure water pressure in the pure water supply path 2 increases. I do. Conversely, when the pure water pressure in the pure water supply path 2 decreases,
Since the flow rate of the chemical liquid introduced into the pure water increases, the pure water pressure fluctuation feedback unit 60A corrects the chemical flow rate operation voltage Vd1 in a direction to decrease the chemical liquid flow rate. 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 chemical liquid flow control valve 21 according to the pressure fluctuation.
The opening degree of the valve becomes larger, and on the contrary, the pure water pressure becomes
When the pressure becomes lower than _0, the opening degree of the chemical liquid flow control valve 21 decreases in accordance with 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.

D7: Modified Example (1) The chemical liquid flow control valve 21 described in the present embodiment is replaced with the chemical liquid introduction valve 9, the chemical liquid supply valve 10, and the chemical liquid of each device of the above-described second and third embodiments. It is also possible to use in place of the pressure regulator 19. In this case, the flow-voltage converter 47 and the pressure-voltage converter 6 shown in FIGS.
2 may be changed in the same manner as described in the fourth embodiment.

(2) In the first to third embodiments, as shown in FIG. 2, the chemical solution introducing valve 9 is connected to the introducing valve connecting pipe 12 interposed in the pure water supply path 2, and In the embodiment, as shown in FIG. 11, the chemical liquid flow 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.

[0128]

As apparent from the above description, the present invention has the following effects. According to the first 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. Even when the flow characteristics change due to the mechanical deformation, the concentration fluctuation of the processing liquid can be suppressed. Further, according to the present invention, the chemical solution flow rate target value and the pure water flow rate target value are set, and the processing solution concentration target value is calculated from these two target values. It is suitable when you want to manage.

According to the second aspect of the present invention, the chemical liquid supply is controlled by operating the valve opening of the chemical liquid flow rate control valve so as to cancel the deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. Since the flow rate of the chemical solution in the path is adjusted, even when the flow rate characteristic of the chemical solution flow rate control valve changes due to thermal deformation, the concentration fluctuation of the processing liquid can be suppressed.
Further, the present invention is suitable for controlling the chemical solution flow rate and the pure water flow rate.

According to the third 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 treatment solution, the current value of the concentration of the treatment solution is obtained by calculation. There is no need to provide a sensor for measuring the concentration.

According to the fourth aspect of the present invention, the pure water pressure in the pure water supply path 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 effect of the invention described in 1 or 2, even when the flow path resistance of the pure water supply path changes, it is possible to suppress the concentration fluctuation of the processing liquid.

According to the fifth 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. Can be higher.

According to the sixth aspect of the invention, when the target value of the chemical 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, the pure water flow rate in the pure water supply passage is set. To
It is possible to accurately follow the target value.

According to the seventh aspect of the 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 to be large. Since the target value of each flow rate is reduced at the stage when the replacement of the substrate has progressed to some extent, the time required for replacing the processing liquid in the substrate processing unit can be reduced.

According to the eighth aspect of the present invention, 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 ninth 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. Even when the flow rate characteristic of the valve changes due to thermal deformation of the valve, the concentration fluctuation of the processing liquid can be suppressed. Further, the present invention is suitable when it is desired to manage the target concentration of the treatment liquid and the target value of the pure water flow rate of the pure water.

According to the tenth aspect of the present invention, the valve opening of the chemical liquid flow rate control valve is operated so as to cancel the deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. Since the flow rate of the chemical solution in the path is adjusted, even when the flow rate characteristic of the chemical solution flow rate control valve changes due to thermal deformation, the concentration fluctuation of the processing liquid can be suppressed. Further, the present invention is suitable when it is desired to manage the target concentration of the treatment liquid and the target value of the pure water flow rate of the pure water.

According to the eleventh aspect, similarly to the third aspect, it is not necessary to provide a sensor for measuring the concentration of the processing solution.

According to the twelfth aspect of the invention, similarly to the fourth aspect of the invention, even when the flow path resistance of the pure water supply path changes, the fluctuation in the concentration of the processing liquid is suppressed. Can be.

According to the thirteenth aspect of the present invention, 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 fourteenth aspect of the present invention, when the target concentration of the processing solution and the target value of the pure water flow rate are set by changing over time, the pure water flow rate in the pure water supply passage is set. To
It is possible to accurately follow the target value.

According to the fifteenth 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 sixteenth 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. Even when the flow rate characteristic of the valve changes due to thermal deformation of the valve, the concentration fluctuation of the processing liquid can be suppressed. Further, the present invention is suitable for managing the target concentration of the treatment liquid and the target value of the chemical flow rate of the chemical liquid.

According to the seventeenth aspect of the present invention, the chemical liquid supply is operated by operating the valve opening of the chemical liquid flow rate control valve so as to cancel the deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. Since the flow rate of the chemical solution in the path is adjusted, even when the flow rate characteristic of the chemical solution flow rate control valve changes due to thermal deformation, the concentration fluctuation of the processing liquid can be suppressed. Further, the present invention is suitable for managing the target concentration of the treatment liquid and the target value of the chemical flow rate of the chemical liquid.

According to the eighteenth aspect, similarly to the third aspect, it is not necessary to provide a sensor for measuring the concentration of the processing solution.

According to the nineteenth aspect, similarly to the fourth 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 be.

According to the twentieth aspect, the target value of the concentration of the processing liquid and the target value of the chemical liquid flow rate of the chemical 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-first aspect of the present invention, the pure water flow target value of the pure water calculated from the concentration target value of the processing liquid and the target flow rate of the chemical solution, each of which changes with time, is obtained. In addition, the flow rate of pure water in the pure water supply path can be accurately followed.

According to the twenty-second aspect of the present invention, while the target value of the chemical solution flow rate is set to be constant over time, the target value of the concentration of the processing solution is set high in the initial stage of the replacement of the processing solution in the substrate processing section. 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 diagram illustrating a schematic configuration of a substrate processing apparatus according to a fourth embodiment.

FIG. 11 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 Pure water pressure fluctuation feedback unit 61 Subtractor 62 Pressure-voltage conversion unit 63 … Adder 64… Pure water pressure Current value calculation section 70 Pure water flow rate feedback control section 71 Subtractor 72 PID calculation section 73 Switch 74 Adder 75 Flow rate-voltage conversion section a1 Chemical liquid flow target value b1 Chemical liquid flow current value a2 Pure Water flow target value b2 ... Pure water flow current value a3 ... Treatment liquid concentration target value b3 ... Treatment liquid concentration current value c1 ... Chemical liquid flow deviation d1 ... Chemical liquid flow operation amount c2 ... Pure water flow deviation d2 ... Pure water flow operation the concentration operation amount of the amount c3 ... treatment liquid density difference 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 ... Jun Water pressure reference value

Claims (22)

[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 solution pumping means for sending the chemical solution in the tank to the chemical solution supply passage, an inlet side connected to the other end of the chemical solution supply passage, an outlet side connected to the pure water supply passage, a chemical solution pressure on the inlet side, and a pure water solution 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 pressure regulator for adjusting the chemical pressure in the passage; Value setting means for setting a target value of a chemical flow rate of a chemical solution and a target value of a pure water flow rate of pure water flowing through the pure water supply path; and a concentration deviation between the target concentration of the processing liquid and the current concentration of the processing liquid. And a chemical liquid concentration feedback control means for adjusting and setting a chemical liquid flow rate operation amount given to the chemical liquid pressure regulator so as to cancel this concentration deviation, wherein the chemical liquid concentration feedback control means comprises: the target value setting means. A concentration target value calculating means for calculating a concentration target value of the processing liquid based on the chemical liquid flow target value and the pure water flow target value given from the processing target; and a concentration target value of the processing liquid given from the concentration target value calculating means. A density deviation calculating means for calculating a density deviation from a current concentration of the processing liquid; a density operation amount calculating means for calculating a density operation amount of the processing liquid to cancel the density deviation; The chemical flow rate control A substrate processing apparatus which comprises an operation quantity conversion means that converts the amount. 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. A chemical liquid flow rate adjusting valve for adjusting a chemical liquid flow rate in the chemical liquid supply path by operating an opening degree of the valve; a chemical liquid flow rate target value of the chemical liquid flowing through the chemical liquid supply path; and a pure liquid flowing through the pure water supply path. Target value setting means for setting a pure water flow rate target value of water; Chemical concentration feedback control means for determining the concentration deviation between the concentration target value of the treatment liquid and the current concentration of the treatment liquid, and adjusting and setting the amount of operation of the chemical flow rate given to the chemical flow control valve so as to cancel the concentration deviation. The chemical concentration feedback control means, based on the chemical flow target value and the pure water flow target value given from the target value setting means, a concentration target value calculating means for calculating the concentration target value of the treatment liquid, A concentration deviation calculating means for calculating a concentration deviation between the target concentration of the processing liquid given by the target concentration value calculating means and a current concentration of the processing liquid; and a concentration manipulated variable of the processing liquid for canceling the concentration deviation. A substrate processing apparatus, comprising: a concentration manipulated variable calculating means for calculating the following; and a manipulated variable converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable. 3. An apparatus according to claim 1, wherein said apparatus further comprises a current concentration value calculating means for calculating a current concentration value 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. A substrate processing apparatus for providing the calculated current value of the concentration of the processing liquid to the concentration deviation calculating means. 4. The apparatus according to claim 1, 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: 5. The substrate processing apparatus according to claim 1, wherein the target value setting unit sets a chemical solution flow target value and a pure water flow target value that change with time. 6. The apparatus according to claim 5, wherein the apparatus is further disposed in the pure water supply path upstream of a position where a chemical solution is introduced into the pure water supply path, and controls a pure water flow rate. Based on the amount, a pure water pressure regulator that adjusts the pure water pressure in the pure water supply path, 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: 7. The apparatus according to claim 5, wherein the target value setting unit starts the supply of the processing liquid into the substrate processing unit filled with pure water and starts processing the inside of the substrate processing unit. Until the replacement with the processing solution is completed,
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. 8. The apparatus according to claim 5, wherein the target value setting means starts the supply of the processing liquid into the substrate processing unit filled with pure water, and starts the processing in the substrate processing unit. Until the replacement with the processing solution is completed,
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. 9. 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 pressure-resistant sealed structure for storing the chemical liquid, a chemical liquid supply path having one end introduced into the chemical liquid in the chemical liquid tank, A chemical solution pumping means for sending a chemical solution in a chemical solution tank to the chemical solution supply passage, an inlet side connected to the other end of the chemical solution supply passage, an outlet side connected to the pure water supply passage, a chemical solution pressure on the inlet side, and a pure solution on the outlet side. A chemical liquid introduction valve for introducing a chemical liquid at a flow rate corresponding to a pressure difference from the water pressure into the pure water supply path, and a chemical liquid flow supply based on a chemical liquid flow rate operation amount determined in relation to a target concentration of the processing liquid. Chemical pressure regulator for adjusting the pressure of the chemical in the road, and target concentration of the treatment liquid And a target value setting means for setting a target value of pure water flow rate of pure water flowing through the pure water supply path; and determining a concentration deviation between a target concentration of the treatment liquid and a current concentration of the treatment liquid. And a chemical solution concentration feedback control means for adjusting and setting a chemical solution flow rate operation amount given to the chemical solution pressure regulator, so that the chemical solution concentration feedback control means comprises a processing solution provided from the target value setting means. A density deviation calculating means for calculating a density deviation between the target concentration value of the processing liquid and the current concentration of the processing liquid; a density operation amount calculating means for calculating a density operation amount of the processing liquid which cancels the concentration deviation; And a manipulated variable converting means for converting the manipulated concentration into the manipulated variable of the chemical flow rate. 10. 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 unit and the pure water supply source, a chemical liquid tank having a pressure-resistant sealed structure for storing a chemical liquid, one end of which is introduced into the chemical liquid in the chemical liquid tank, and the other end is the pure water. A chemical liquid supply path connected in the middle of the supply path, a chemical liquid pressure feeding means for sending the chemical liquid in the chemical liquid tank to the chemical liquid supply path, and a chemical liquid flow rate operation amount determined in relation to the target concentration of the processing liquid. A chemical liquid flow rate control valve for adjusting the flow rate of the chemical liquid in the chemical liquid supply path by manipulating the opening degree of the valve; a target concentration value of the treatment liquid and a target pure water flow value of pure water flowing through the pure water supply path Target value setting means for setting a concentration target of the processing solution And a chemical concentration feedback control means for adjusting and setting a chemical flow rate operation amount to be applied to the chemical flow control valve so as to cancel the concentration deviation. Concentration feedback control means, a concentration deviation calculating means for calculating a concentration deviation between the target concentration of the processing liquid given from the target value setting means and a current concentration of the processing liquid, a processing liquid for canceling the concentration deviation A substrate processing apparatus, comprising: a concentration manipulated variable calculating means for calculating a concentration manipulated variable of the above; and an operation amount converting means for converting the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable. 11. An apparatus according to claim 9, wherein said apparatus further comprises a current concentration value calculating means for calculating a current concentration value 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. A substrate processing apparatus for providing the calculated current value of the concentration of the processing liquid to the concentration deviation calculating means. 12. The apparatus according to claim 9, 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: 13. The substrate processing apparatus according to claim 9, 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. 14. The apparatus according to claim 13, wherein the apparatus is further disposed in the pure water supply path upstream of a position where a chemical solution is introduced into the pure water supply path, and controls a pure water flow rate. Based on the amount, a pure water pressure regulator that adjusts the pure water pressure in the pure water supply path, 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: 15. The apparatus according to claim 13, wherein the target value setting unit starts supplying the processing liquid into the substrate processing unit filled with pure water, and then starts the processing liquid supply from the substrate processing unit. Until the replacement with the processing solution is completed,
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. 16. 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 solution pumping means for sending the chemical solution in the tank to the chemical solution supply passage, an inlet side connected to the other end of the chemical solution supply passage, an outlet side connected to the pure water supply passage, a chemical solution pressure on the inlet side, and a pure water solution 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 pressure regulator that adjusts the pressure of the chemical in the road; Target value setting means for setting a target value of the flow rate of the chemical solution flowing through the chemical solution supply path, and a density deviation between the target concentration value of the processing liquid and the current concentration value of the processing liquid, and canceling the density deviation. And a chemical concentration feedback control means for adjusting and setting a chemical flow rate operation amount given to the chemical pressure regulator, wherein the chemical concentration feedback control means comprises: a concentration target of the treatment liquid given from the target value setting means. A pure water flow target value calculating means for calculating a pure water flow target value of pure water based on the value and the chemical liquid flow target value; a processing liquid concentration target value provided from the target value setting means; Concentration deviation calculating means for calculating a concentration deviation from the current concentration value; concentration operation amount calculating means for calculating a concentration operation amount of the processing liquid which cancels the concentration deviation; and Operation to convert to A substrate processing apparatus which comprises a quantity conversion means. 17. 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 treatment of the substrate with a 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 target concentration value of the treatment liquid and a target chemical liquid flow rate value of the chemical liquid flowing through the chemical liquid supply path are set. Target value setting means; and a target concentration value of the processing solution. A chemical concentration feedback control means for adjusting and setting a chemical flow rate operation amount given to the chemical flow rate control valve so as to cancel the concentration deviation and obtain a concentration deviation from the current concentration value of the physiological solution; A feedback control unit configured to calculate a pure water pure water flow target value based on the treatment liquid concentration target value and the chemical liquid flow target value provided from the target value setting unit; Concentration deviation calculating means for calculating a concentration deviation between the processing liquid concentration target value given by the target value setting means and the processing liquid concentration present value; and a processing liquid concentration manipulated variable for canceling the concentration deviation. A substrate processing apparatus comprising: a concentration manipulated variable calculation unit; and an operation amount conversion unit configured to convert the calculated concentration manipulated variable into a chemical liquid flow rate manipulated variable. 18. The apparatus according to claim 16, 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 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. 19. The apparatus according to claim 16, further comprising a pure water supply passage disposed upstream of a position where 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 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. 20. The substrate processing apparatus according to claim 16, wherein the target value setting unit sets a target concentration of the processing liquid and a target value of the chemical flow rate, each of which changes with time. 21. The apparatus according to claim 20, wherein the apparatus is further disposed on the pure water supply path upstream of a position where a chemical solution is introduced into the pure water supply path, and controls a pure water flow rate. A pure water pressure regulator that adjusts the pure water pressure in the pure water supply path based on the amount, a pure water flow target value provided from the pure water flow target value calculation means, and a pure water flow current value. A substrate processing apparatus comprising: a pure water flow rate feedback control unit that calculates a deviation, calculates a pure water flow operation amount that cancels the pure water flow deviation, and gives the pure water flow operation amount to the pure water pressure regulator. 22. The apparatus according to claim 20, wherein the target value setting unit starts the supply of the processing liquid into the substrate processing unit filled with pure water and starts processing the substrate processing unit. Until the replacement with the processing solution is completed,
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.