JP5448521B2 - Treatment liquid supply apparatus and treatment liquid supply method - Google Patents

Description

  The present invention relates to an apparatus and a method for supplying a processing liquid for processing a processing target such as a substrate. An example of a processing target is a substrate. Examples of the substrate include a semiconductor wafer, a liquid crystal display substrate, a plasma display substrate, an FED (Field Emission Display) substrate, an optical disk substrate, a magnetic disk substrate, a magneto-optical disk substrate, and a photomask substrate. included.

  In a semiconductor element manufacturing process, a semiconductor wafer as an example of a substrate is processed using a processing liquid. Further, in the manufacturing process of the liquid crystal display device and other display devices, the surface of the glass substrate or the like is processed using a processing liquid. One example of a substrate processing apparatus for performing such processing is a single wafer processing apparatus that processes substrates one by one. A single wafer processing apparatus includes a spin chuck that holds and rotates a single substrate, and a processing liquid nozzle that supplies a processing liquid (chemical solution or rinsing liquid) to the substrate held by the spin chuck. Is provided in the main body of the processing apparatus. In order to supply the processing liquid to the processing liquid nozzle, a chemical liquid cabinet is provided separately from the processing apparatus main body. The chemical liquid cabinet and the processing apparatus main body are connected by piping. The processing liquid (chemical liquid) is supplied from the chemical liquid cabinet to the processing liquid nozzle in the processing apparatus main body through this pipe.

  The chemical liquid cabinet includes a chemical tank and a pump. The chemical liquid pumped out from the chemical liquid tank by the pump is supplied to the processing liquid nozzle through the chemical liquid piping and the chemical liquid valve. When the chemical solution is not discharged from the processing solution nozzle, the chemical solution is returned to the chemical solution tank through a return path connected to the chemical solution pipe before the chemical solution valve. Thereby, a circulation path for constantly circulating the chemical solution is formed. A temperature controller is arranged in the circulation path so as to keep the temperature of the chemical solution at an appropriate value. When the chemical solution supplied to the substrate is recovered and reused, the used chemical solution guided from the substrate processing unit through the recovery pipe is introduced into the chemical solution tank.

JP 2006-351709 A

  A chemical | medical solution may consist of a liquid mixture of a some component liquid. For example, a chemical solution for substrate processing may be prepared by mixing a first chemical solution stock solution, a second chemical solution stock solution, and pure water (DIW: deionized water) at a predetermined mixing ratio. More specifically, by using ammonia water as the first chemical stock solution, hydrogen peroxide solution as the second chemical stock solution, and mixing ammonia water, hydrogen peroxide solution and pure water at a predetermined mixing ratio, SC1 It is possible to prepare a chemical solution called

It is preferable that the component concentration of each component constituting the chemical solution stored in the chemical solution tank is maintained within a certain range. As a result, stable high-quality processing can be performed on the substrate.
However, while circulating the chemicals or collecting used chemicals, the concentration of the chemicals in the chemicals tank may decrease, and any of the component concentrations may be outside the allowable range. .
This problem can be solved by providing a component concentration measuring device for measuring the component concentration of the chemical solution and replenishing the corresponding component solution when the component concentration of any of the components becomes less than a predetermined value.

However, if the component liquid of the deficient component is supplied in a single liquid state, the concentration of the chemical liquid in the chemical liquid tank will be uneven, so a stable time is required until the concentration of the component liquid diffuses and becomes uniform in the chemical liquid tank. It becomes. In the meantime, since the substrate cannot be processed, the productivity may be impaired. If substrate processing is continued without waiting for a stable time, processing quality is sacrificed.
There is also a problem that the amount of the component liquid to be replenished in order to make the component concentration within the allowable range cannot be specified in advance. This is because the total amount of the chemical solution remaining in the chemical solution tank when the component concentration of any of the components becomes less than a predetermined value is generally unknown. That is, in a general chemical tank, only the replenishment liquid level that requires replenishment of chemical liquid and the replenishment stop liquid level for replenishment stoppage are detected. No means for detecting an intermediate liquid level is provided. Therefore, even if an insufficient concentration of any of the components is detected in an intermediate liquid level state, the total amount of the chemical solution in the chemical solution tank at that time cannot be known. Therefore, the necessary replenishment amount of the component liquid cannot be specified.

  In such a situation, it is necessary to replenish the component liquid of the insufficient component little by little so that the composition of the chemical liquid in the chemical tank does not change suddenly. Therefore, since it is necessary to supply the insufficient component in small amounts and to stabilize the concentration, it takes a long time to restore the component concentration of the insufficient component to a value within the allowable range, which may significantly impair the productivity. . This problem becomes more serious when the component concentration tolerance is narrow.

  Furthermore, since the supply amount is completely different between when the liquid is supplied with the chemical tank empty and when the component liquid is replenished when the component concentration is insufficient, it is necessary to provide a dedicated supply system for single liquid replenishment in small amounts. There is. For example, a supply system equipped with a pump is used to supply liquid when the chemical tank is empty, while a supply system that replenishes component liquids in small amounts by gas pressurization in the sealed tank is necessary when replenishing component liquids. is there. Furthermore, there is a possibility that it is necessary to use a supply system that dilutes and supplies component liquids in order to alleviate concentration fluctuations due to single liquid replenishment. Furthermore, if the flow rate is monitored in order to reliably supply the component liquid at a minute flow rate, an ultrasonic flow meter or other high-precision equipment may be required. Therefore, if a dedicated supply system is provided for replenishing the component liquid, the configuration becomes complicated and the cost increases accordingly.

  Accordingly, an object of the present invention is to provide a processing liquid supply apparatus and a processing liquid supply method capable of correcting the component concentration of a processing liquid without significantly impairing productivity.

The invention according to claim 1 for achieving the above object is a process for storing the processing liquid (14) to be supplied to the processing section (5) for performing processing with the processing liquid on the processing target (W). A liquid tank (10), a processing liquid charging path (25) for charging the processing liquid into the processing liquid tank, and a middle of the processing liquid charging path (more specifically, a pipe that constitutes the processing liquid charging path) And a mixing means (11) for combining and mixing a plurality of component liquids constituting the processing liquid, and a component concentration measuring means for measuring the component concentrations of the plurality of components contained in the processing liquid in the processing liquid tank ( 20) and component liquid supply amount calculating means (30, S9, S10) for calculating the supply amount of each component liquid according to the component concentration measured by the component concentration measuring means and the target value of the component concentration The component liquid supply calculated by the component liquid supply amount calculation means According to the amount, supply control means (30, S5, S6, S7, S16, S21, S32˜) for supplying the mixed liquid obtained by mixing to the processing liquid tank while mixing the plurality of component liquids manually. S41) and a processing liquid amount detecting means (13) for detecting the processing liquid amount in the processing liquid tank, wherein the component liquid supply amount calculating means detects the processing liquid amount detected by the processing liquid amount detecting means. The total supply amount calculating means (S9) for obtaining the total supply amount of the processing liquid to be supplied to the processing liquid tank, the total supply amount obtained by the total supply amount calculating means, and the component concentration measuring means A processing liquid supply apparatus including individual supply amount calculation means (S10) for calculating the individual supply amount of each component liquid according to the component concentration and the target value of the component concentration . In addition, although the alphanumeric character in a parenthesis represents the corresponding component etc. in below-mentioned embodiment, it is not the meaning which limits a claim to embodiment. The same applies hereinafter.

  According to this configuration, the supply amount of each of the plurality of component liquids constituting the processing liquid is determined according to the component concentration (measured value) of the processing liquid in the processing liquid tank and the target value. The plurality of component liquids having the respective supplied amounts are mixed by the mixing means to be in a mixed liquid state, and the mixed liquid is supplied to the processing liquid tank. Thereby, the component density | concentration of the process liquid in a process liquid tank can be correct | amended. And compared with the case where the component liquid is supplied as a single liquid, it is possible to greatly suppress the occurrence of uneven concentration in the processing liquid tank. Therefore, the stabilization time until the density unevenness is eliminated is unnecessary, or even if it is necessary, a short time is required, so that the productivity related to the processing to be processed can be improved.

In addition, since component liquids are not supplied individually but in the form of a mixed liquid mixed with other component liquids, it is not necessary to supply each component liquid at a minute flow rate, and processing when the processing liquid is empty There is no need to provide a supply system separate from the liquid supply system. Therefore, the configuration is not complicated and the cost is not increased.
The mixing means includes a pipe-shaped mixing section (26, for example, a manifold) interposed in a pipe constituting the processing liquid charging path, and a plurality of components connected between the mixing section and a plurality of component liquid supply sources. It may include component liquid piping (31 to 33) and on-off valves (34 to 36) respectively interposed in the plurality of component liquid piping.

In the present invention, the amount of the processing liquid in the processing liquid tank is further detected, and the total supply amount of the processing liquid to be supplied to the processing liquid tank is obtained based on the detected amount of the processing liquid. The individual supply amount of each component liquid is calculated according to the total supply amount, the measured component concentration, and the target value of the component concentration. This calculated individual supply amount of component liquid is supplied to the processing liquid tank while being mixed by the mixing means.

  The treatment liquid is prepared by mixing a plurality of component liquids at a predetermined mixing ratio (target mixing ratio). In the treatment liquid thus prepared, the component concentrations of the plurality of components are equal to or very close to the target value. When the component concentration measured by the component concentration measuring means deviates from the target value, the component is excessive or insufficient. Therefore, when the processing liquid of the total supply amount is replenished, the total supply amount is divided at a ratio different from the predetermined mixing ratio, thereby obtaining the individual supply amounts of the individual component liquids. Specifically, if there is an insufficient component, the proportion of the corresponding component liquid is increased, and if there is an excess component, the total supply amount is prorated according to the ratio of decreasing the proportion of the corresponding component liquid. Desired. Thereby, by mixing a plurality of component liquids of the respective individual supply amounts obtained and supplying them to the processing liquid tank, the excess or deficiency of the components in the processing liquid tank is corrected, and the concentration of the components is restored to an appropriate value. be able to.

More specifically, by obtaining the individual supply basic value of each component according to the target mixing ratio (predetermined mixing ratio) and correcting the basic value according to the deviation between the measured component concentration and the target component concentration value. The individual supply amount may be obtained.
The processing liquid amount detecting means is an intermediate level process between a charging start level (charging lower limit level) at which the processing liquid should be started and a charging stop level (charging upper limit level) at which the processing liquid should be stopped. It is preferable that the amount of the processing liquid in the processing liquid tank is detected stepwise or continuously so that the liquid amount can be detected. What is necessary is just to determine the number of steps at the time of detecting the amount of processing liquid step by step according to the fluctuation | variation tolerance range of the component density | concentration in a processing liquid. Since the processing liquid amount detection accuracy decreases as the number of stages decreases, an error occurs in the calculation of the individual supply amount for returning the component concentration to the target value accordingly. The number of steps may be determined so that this error falls within an allowable range.

The processing liquid amount detecting means may be a liquid level detecting means (50) for detecting the liquid level in the processing liquid tank, or a weight measuring means for measuring the weight of the processing liquid in the processing liquid tank. Also good.
The invention according to claim 2 is characterized in that the individual supply amount calculating means compensates for the insufficient concentration of the insufficient component whose component concentration measured by the component concentration measuring means is insufficient. The processing liquid supply apparatus according to claim 1, wherein an additional replenishment amount of the component liquid to be replenished to the liquid is obtained, and an individual supply amount of each component liquid is calculated using the additional replenishment amount.
According to a third aspect of the present invention, the individual supply amount calculation means obtains a basic individual replenishment amount of each component liquid by dividing an amount obtained by subtracting the additional replenishment amount from the total replenishment amount by a predetermined mixing ratio, and the insufficient component The processing liquid supply apparatus according to claim 2, wherein the basic individual replenishment amount is corrected with the additional replenishment amount to calculate the individual replenishment amount of the insufficient component.
According to a fourth aspect of the present invention, the mixing means includes individual flow rate control means (67 to 69) for individually controlling the supply flow rates of a plurality of component liquids, and the supply control means includes the component liquid supply amount calculation means. The individual flow rate control unit is controlled so that the plurality of component liquids are mixed at a mixing ratio corresponding to each component liquid supply amount calculated by the calculation according to any one of claims 1 to 3. The processing liquid supply apparatus.

  According to this configuration, the supply flow rate of each component is individually controlled so that the component liquids are mixed at a mixing ratio corresponding to the supply amount of each component. Therefore, by starting the supply of a plurality of component liquids simultaneously and stopping the supply of them simultaneously, each component liquid can be supplied to the treatment liquid tank by an individual supply amount. As a result, all component liquids can be supplied to the treatment liquid tank in a state of being mixed with other component liquids. In other words, the component liquid is not supplied in a single liquid state. Thereby, the density | concentration unevenness in a process liquid tank can be suppressed more effectively.

It is preferable that the said individual flow control means is interposed by the component liquid piping (31-33) connected to the said mixing part.
The invention according to claim 5 further includes a charging stop level detecting means (54) for detecting that the amount of the processing liquid in the processing liquid tank has reached a predetermined charging stop level, wherein the total supply amount calculating means includes When the component concentration of any of the treatment liquids is less than a predetermined control lower limit, the total supply amount required to increase the amount of treatment liquid in the treatment liquid tank to the charging stop level is calculated. The supply control unit simultaneously stops the supply of the plurality of component liquids in response to the detection of the input stop level detecting unit that the amount of the processing liquid in the processing liquid tank has reached the input stop level. The processing liquid supply apparatus according to claim 4, wherein

  According to this configuration, when any component concentration of the processing liquid becomes less than the predetermined control lower limit, the difference between the processing liquid amount at that time and the charging stop level is calculated as the total supply amount. The supply amount of each component liquid can be obtained by apportioning the total supply amount at a ratio corresponding to each component concentration and each target value. The supply of the component liquid is stopped as soon as the amount of the processing liquid in the processing liquid tank reaches the charging stop level. Therefore, in a simple control of stopping the supply of all component liquids in response to the amount of the processing liquid reaching the charging stop level, replenish the processing liquid tank with the insufficient components mixed with other components, The density of the insufficient component can be corrected.

Specifically, the supply control means starts supplying the mixed liquid by simultaneously opening a plurality of component liquid on-off valves (34 to 36) respectively interposed in the plurality of component liquid pipes, and simultaneously supplying them. The supply of the liquid mixture may be stopped by closing.
According to a sixth aspect of the present invention, the supply total amount calculating means is configured to stop the predetermined amount of the processing liquid in the processing liquid tank when any of the component concentrations of the processing liquid falls below a predetermined control lower limit. The total supply amount required to increase to the level is calculated, and the supply control means includes a supply time measurement means (30) for measuring the supply time of the mixed liquid, and the supply time measurement means 5. The processing liquid supply apparatus according to claim 4 , wherein the supply of the plurality of component liquids is stopped simultaneously in response to measuring the time corresponding to the total amount (S16).

  If the supply of the processing liquid to the processing unit is continued while the processing liquid is being supplied by the operation of the supply control means, the amount of the processing liquid in the processing liquid tank decreases. For this reason, when the processing liquid is supplied until the processing liquid amount in the processing liquid tank reaches the charging stop level, more processing liquid than the calculated total supply amount is supplied into the processing liquid tank. In other words, each component liquid is supplied to the treatment liquid tank more than the calculated individual component supply amount. At this time, the component concentration determined to be lower than the target value is higher than the target value, and the other component concentrations may be lower than the target value accordingly.

Therefore, in the present invention, the component liquid is supplied for a time corresponding to the total supply amount. As a result, the amount of the processing liquid in the processing liquid tank may not reach the charging stop level, but the concentration of each component of the processing liquid in the processing liquid tank becomes an appropriate value after the supply ends. That is, the processing liquid in the processing liquid tank can have a desired component ratio.
The supply time measuring means preferably measures the elapsed time from the start of the supply of the mixed solution in order to eliminate the shortage in response to any shortage of the component concentration.

The invention described in claim 7 further includes a total supply amount measuring means (28) for measuring the total supply amount of the mixed liquid, and the supply control means is configured such that the total supply amount of the mixed liquid measured by the total supply amount measuring means is The processing liquid supply apparatus according to claim 4 , wherein the supply of the plurality of component liquids is stopped simultaneously (S21) in response to reaching the total supply amount calculated by the total supply amount calculation means.

According to this configuration, since the supply of the treatment liquid is controlled based on the actual supply total amount, each component liquid is reliably supplied by the calculated individual supply amount. That is, the same effect as that of the invention of claim 5 can be realized.
The total supply amount measuring means preferably measures the total supply amount after starting the supply of the mixed liquid in order to eliminate the shortage in response to any shortage of the component concentration.

The invention according to claim 8 further includes a plurality of individual supply amount measuring means (67 to 69) that respectively measure the supply amounts of the plurality of component liquids before mixing, and the supply control means includes the individual supply amount measuring means. when the supply amount of each component liquid reaches the calculated value by the component liquid supply amount calculating means which is measured by stopping the supply of each component liquid (S35, S38, S41) is intended, according to claim 4, wherein The processing liquid supply apparatus.

  According to this configuration, since the supply of the component liquid is controlled based on the actual supply amount of the individual component liquid, each component liquid can be reliably supplied by the calculated individual supply amount. That is, the same effect as that of the invention of claim 5 can be realized. The supply / stop of the component liquids may be individually controlled. Even in this case, since the flow rate ratio is determined according to the individual supply amount, if the supply of a plurality of component liquids is started at the same time, they are simultaneously performed. Supply will be stopped.

The individual supply amount measuring means preferably measures the individual supply amount after starting the supply of the mixed liquid in order to eliminate the shortage in response to any shortage of the component concentration.
The invention according to claim 9 further includes a plurality of individual supply amount measuring means (67 to 69) that respectively measure the supply amounts of the plurality of component liquids before mixing, and the mixing means includes a plurality of components constituting the treatment liquid. The plurality of component liquids are merged in the processing liquid supply path at a flow rate ratio corresponding to the target mixing ratio of the component liquids, and the supply control unit is configured to measure each component liquid measured by the individual supply amount measuring unit. when the amount of the supply has reached the calculated value by the component liquid supply amount calculating means stops the supply of the plurality of component liquid individually (S35, S38, S41) is intended, the processing liquid according to claim 1, wherein It is a supply device.

  In this configuration, the component liquids are mixed at the mixing target value (optimal value (default value) for processing the object to be processed) and supplied to the processing liquid tank, and the individual component liquids are supplied in the corresponding individual supply amounts. The Therefore, component liquids with insufficient concentration will be supplied over a longer time than other component liquids, but the supply state with a single liquid will be extremely short, so there will be a large concentration unevenness in the processing liquid tank. There is no risk of it occurring.

The supply control means preferably starts supplying the plurality of component liquids simultaneously. As a result, even if a component liquid corresponding to a component with insufficient concentration is supplied as a single liquid, since the total amount of the processing liquid in the processing liquid tank is increased, a sudden change in the component concentration in the processing liquid tank is suppressed. it can.
Invention of Claim 10 supplies the process liquid (14) stored by the process liquid tank (10) to the process part (5) for performing the process with a process liquid to a process target (W), A plurality of components constituting the treatment liquid according to the step of measuring the component concentrations of the plurality of components contained in the treatment liquid in the treatment liquid tank, the measured component concentration, and the target value of the component concentration The component liquid supply amount calculating step for calculating each supply amount of the component liquid, and the plurality of component liquids in the middle of the processing liquid input path for supplying the processing liquid to the processing liquid tank according to the calculated component liquid supply amount And supplying the mixed liquid obtained by mixing to the processing liquid tank and detecting the amount of the processing liquid in the processing liquid tank, and the component liquid supply amount calculating step Is based on the detected amount of the processing liquid, based on the processing liquid tank The individual supply amount of each component liquid is calculated according to the step of determining the total supply amount of the processing liquid to be supplied, the calculated total supply amount, the measured component concentration, and the target value of the component concentration. A process liquid supply method including a process. By this method, the same effect as that of the invention of claim 1 can be realized.

The invention according to claim 11 includes a step of individually controlling the supply flow rates of the plurality of component liquids such that the plurality of component liquids are mixed at a mixing ratio according to the calculated component liquid supply amount. The processing liquid supply method according to claim 10 , further comprising: By this method, an effect similar to that of the invention of claim 4 can be realized.
Regarding the invention of the processing liquid supply method, the same modification as in the case of the processing liquid supply apparatus is possible.

It is a conceptual diagram for demonstrating the structure of the process liquid supply apparatus which concerns on 1st Embodiment of this invention. It is a flowchart for demonstrating the operation example of the said process liquid supply apparatus. It is a flowchart for demonstrating the other operation example of the said process liquid supply apparatus. It is a flowchart for demonstrating the operation example of the process liquid supply apparatus which concerns on 2nd Embodiment of this invention. It is a conceptual diagram for demonstrating the structure of the process liquid supply apparatus which concerns on 3rd Embodiment of this invention. It is a flowchart for demonstrating the operation example of the process liquid supply apparatus of FIG. It is a conceptual diagram for demonstrating the structure of the process liquid supply apparatus which concerns on 4th Embodiment of this invention. It is a flowchart for demonstrating the operation example of the process liquid supply apparatus of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a conceptual diagram for explaining the configuration of a processing liquid supply apparatus according to the first embodiment of the present invention. A chemical liquid cabinet 1 as a processing liquid supply apparatus constitutes a substrate processing apparatus 3 together with a processing apparatus main body 2. The processing apparatus body 2 includes a single wafer processing unit 5 that processes the substrates W one by one. The chemical liquid cabinet 1 supplies the prepared chemical liquid as the processing liquid toward the substrate processing unit 5. The substrate W may be a semiconductor wafer, for example.

  The substrate processing unit 5 includes a processing cup 6, a spin chuck 7, and a processing liquid nozzle 8. The processing cup 6 is a cylindrical container body and defines a processing space inside thereof. A spin chuck 7 is accommodated in this processing space. The spin chuck 7 is a substrate holding and rotating mechanism that holds the substrate W in a substantially horizontal posture and rotates it around a vertical rotation axis that passes through the center of the substrate W. The processing liquid nozzle 8 supplies the processing liquid toward the surface of the substrate W held by the spin chuck 7 (upper surface in the example of FIG. 1). Thereby, the surface of the substrate W is processed with the processing liquid.

The chemical liquid cabinet 1 includes a processing liquid tank 10, a mixing mechanism 11, a supply mechanism 12, a processing liquid amount measuring mechanism 13, and a control device 30.
The processing liquid tank 10 is a container for storing the processing liquid 14 to be supplied to the processing liquid nozzle 8. The processing liquid tank 10 and the processing liquid nozzle 8 are connected by a processing liquid supply pipe 15.
A temperature controller 16, a pump 17, a filter 18, and a component concentration measuring device 20 are interposed in the processing liquid supply pipe 15 in order from the processing liquid tank 10 side. These constitute the supply mechanism 12. The temperature controller 16 is a heating or cooling device that exchanges heat with the processing liquid 14 flowing through the processing liquid supply pipe 15 in order to adjust the processing liquid to an appropriate temperature (for example, a temperature different from room temperature). . The filter 18 removes foreign matters in the processing liquid 14 that flows through the processing liquid supply pipe 15. The pump 17 is composed of, for example, a bellows pump, pumps the processing liquid 14 from the processing liquid tank 10, and feeds the processing liquid 14 toward the processing liquid nozzle 8 through the processing liquid supply pipe 15. The component concentration measuring device 20 measures the concentration of each of a plurality of components constituting the processing liquid 14. More specifically, the component concentration measuring device 20 measures the ultrasonic wave propagation speed in the processing liquid, measures the conductivity of the processing liquid, measures the light (infrared) absorbance of the processing liquid, and so on. A component concentration may be detected.

Further, the substrate processing unit 5 is provided with a processing liquid valve 9 interposed in the processing liquid supply pipe 15 on the upstream side of the processing liquid nozzle 8. By opening and closing the processing liquid valve 9, it is possible to switch the discharge / stop of the processing liquid 14 from the processing liquid nozzle 8.
In the substrate processing section 5, one end of the processing liquid feedback pipe 22 is located at a branch position 21 (in the vicinity of the processing liquid valve 9) determined upstream of the processing liquid valve 9 in the processing liquid supply pipe 15. Is branched. The other end of the processing liquid return pipe 22 is led to the processing liquid tank 10. A return valve 23 is interposed in the vicinity of the branch position 21 in the substrate processing unit 5 in the processing liquid return pipe 22.

  When the processing liquid valve 9 is closed, the feedback valve 23 is opened, and the processing liquid from the processing liquid supply pipe 15 is returned to the processing liquid tank 10 through the processing liquid feedback pipe 22. Thus, a circulation path is formed by the processing liquid supply pipe 15 and the processing liquid return pipe 22. By circulating the processing liquid 14 through this circulation path, the processing liquid 14 is adjusted to an appropriate temperature by the temperature controller 16, and foreign matters in the processing liquid 14 are removed by the filter 18. Therefore, when the processing liquid valve 9 is opened, a clean processing liquid 14 adjusted to an appropriate temperature is immediately discharged from the processing liquid nozzle 8 toward the substrate W.

When the processing liquid valve 9 is opened, the feedback valve 23 is closed. Thereby, the processing liquid 14 fed by the pump 17 is guided to the processing liquid nozzle 8.
The mixing mechanism 11 mixes a plurality of component liquids to prepare a processing liquid, and throws the prepared processing liquid (new processing liquid) into the processing liquid tank 10. The mixing mechanism 11 includes a processing liquid input pipe 25, a mixing unit 26, component liquid supply pipes 31, 32, 33, component liquid valves 34, 35, 36, and a flow rate controller (LFC: micro liquid flow rate controller) 37. , 38, 39.

  One end of the processing liquid input tube 25 is coupled to the mixing unit 26, and the other end is introduced into the processing liquid tank 10. The mixing part 26 is comprised with a manifold and forms a part of piping. One end of each of the component liquid supply pipes 31, 32, 33 is coupled to the mixing unit 26, and the component liquids supplied from these component liquid supply pipes 31, 32, 33 are merged inside the mixing unit 26. A mixture of them is prepared. This mixed liquid is introduced into the treatment liquid tank 10 through the treatment liquid introduction pipe 25. The other ends of the component liquid supply pipes 31, 32, 33 are connected to component liquid supply sources 41, 42, 43, respectively. For example, the component liquid supply source 41 is a first chemical liquid supply source, the component liquid supply source 42 is a second chemical liquid supply source, and the component liquid supply source 43 is a pure water (DIW: deionized water) supply source. It may be. More specifically, the first chemical solution may be ammonia water and the second chemical solution may be hydrogen peroxide solution. In this case, ammonia water, hydrogen peroxide water, and pure water are mixed in the mixing unit 26, and a treatment liquid called SC1 can be prepared.

  The component liquid supply pipe 31 is provided with a flow rate controller 37 and a component liquid valve 34 in order from the component liquid supply source 41 side. The component liquid supply pipe 32 is provided with a flow rate controller 38 and a component liquid valve 35 in order from the component liquid supply source 42 side. Similarly, the component liquid supply pipe 33 is provided with a flow rate controller 39 and a component liquid valve 36 in order from the component liquid supply source 43 side. Therefore, the supply / stop of each component liquid can be controlled by opening and closing the component liquid valves 34, 35, and 36 individually. Further, the flow rate of each component liquid can be individually controlled by the flow rate controllers 37, 38, and 39. Therefore, the three types of component liquids can be mixed at a mixing ratio corresponding to the flow rate controlled by the flow rate controllers 37, 38, and 39.

  The processing liquid amount measuring mechanism 13 measures the processing liquid amount in the processing liquid tank 10 and inputs the measurement result to the control device 30. In this embodiment, the processing liquid amount measurement mechanism 13 includes a plurality of liquid level sensors 50 that detect different liquid level heights in the processing liquid tank 10. The plurality of liquid level sensors 50 include a lower limit liquid level sensor 51, an upper limit liquid level sensor 52, a replenishment liquid level sensor 53, a replenishment stop liquid level sensor 54, and at least one (preferably a plurality of) intermediate liquid level sensors. L1 to Ln (n = 1, 2, 3,...).

  The lower limit liquid level sensor 51 detects the lower limit height of the liquid level in the processing liquid tank 10, and when the liquid level falls below this lower limit height, the processing apparatus body 2 and the chemical liquid cabinet 1 operate with an alarm. Stop. The upper limit liquid level sensor 52 detects the upper limit height of the liquid level in the processing liquid tank 10, and when the liquid level exceeds the upper limit height, the processing apparatus main body 2 and the chemical liquid cabinet 1 operate with an alarm. Stop.

  The replenishing liquid level sensor 53 detects a replenishing liquid level higher than the lower limit height relatively below the processing liquid tank 10. The replenishment stop liquid level sensor 54 detects a replenishment stop liquid level lower than the upper limit height relatively above the treatment liquid tank 10 (above the replenishment liquid level). When the liquid level in the processing liquid tank 10 is lowered to the replenishing liquid level by using the processing liquid 14, the replenishment of the processing liquid from the mixing mechanism 11 to the processing liquid tank 10 is started, and the liquid level is the replenishment stop liquid level. Is reached, the supply of the processing liquid is stopped. Thus, during normal operation, the liquid level in the processing liquid tank 10 is held between the detection levels (replenishment liquid level and replenishment stop liquid level) by the replenishment liquid level sensor 53 and the replenishment stop liquid level sensor 54. .

  The intermediate liquid level sensors L1 to Ln detect the liquid level in an intermediate region between the replenishment liquid level and the replenishment stop liquid level. When a plurality of intermediate liquid level sensors L1 to Ln are provided, these respectively detect the liquid level heights determined so as to increase in the order of L1, L2,..., Ln. Thereby, the liquid level in the intermediate region can be detected stepwise. Of course, as the number of the intermediate liquid level sensors L1 to Ln increases, the detection resolution of the liquid level increases.

  Instead of detecting the liquid level height stepwise by the plurality of intermediate liquid level sensors L1 to Ln, a sensor for continuously detecting the liquid level height may be provided. Examples of such sensors include back pressure type liquid level sensors and distance sensors that detect the distance from a predetermined height to the liquid level. The back pressure type liquid level sensor detects, for example, the gas pressure in the gas supply pipe while supplying the inert gas to the gas supply pipe introduced into the processing liquid tank 10 from the upper side to the lower side with a small pressure. It is. That is, since the atmospheric pressure in the pipe changes according to the liquid level in the gas supply pipe, the liquid level in the processing liquid tank 10 can be continuously detected by detecting this atmospheric pressure. The distance sensor can be composed of an optical distance sensor or an ultrasonic distance sensor.

  The control device 30 has a basic configuration as a microcomputer, includes a CPU and necessary memory, and is programmed in advance so as to be able to execute the operations described below. The control device 30 controls operations of the temperature controller 16, the pump 17, the component concentration measuring device 20, the component liquid valves 34 to 36, and the flow rate controllers 37 to 39. In addition, the measurement result of the component concentration measuring device 20 and the detection signals of the plurality of liquid level sensors 50 are input to the control device 30.

  The control device 30 may control only the components of the chemical liquid cabinet 1 or may control the components of the processing device main body 2 together. In other words, the control unit (30) provided in the processing apparatus main body 2 may be configured to control the components of the chemical liquid cabinet 1 together. In these cases, the control device 30 executes opening / closing control of the processing liquid valve 9 and the feedback valve 23 together.

FIG. 2 is a flowchart illustrating an example of an operation that the control device 30 repeats at each control cycle, and illustrates a process liquid supply operation to the process liquid tank 10.
The control apparatus 30 acquires the measurement result of the component concentration measuring device 20, and calculates | requires the component concentration of the some component which comprises the process liquid 14 (step S1). For example, when the processing liquid 14 is SC1 (a mixed liquid of ammonia water, hydrogen peroxide water and pure water), the component concentration measuring device 20 detects the ammonia concentration in the processing liquid 14 as one component concentration. Then, the hydrogen peroxide concentration is detected as another component concentration. In the control device 30, a concentration management range (allowable concentration range) is set for each component concentration to be monitored. More specifically, a control lower limit and a control upper limit are set in advance for each component concentration.

  The control device 30 compares the component concentration of each component with the corresponding control lower limit, and determines whether there is a component with insufficient concentration (insufficient component) (step S2). If there is no component with insufficient concentration (step S2: NO), the controller 30 further refers to the output of the replenishing liquid level sensor 53, and the liquid level in the processing liquid tank 10 does not fall below the replenishing liquid level. Is determined (step S3). If the liquid level is equal to or higher than the replenishing liquid level (step S3: NO), the process of the control cycle is terminated.

  When the liquid level is lower than the replenishing liquid level (step S3: YES), the control device 30 sets the supply flow rate of the component liquid to a predetermined value (step S4). The default value is a value that is a flow rate ratio (default flow rate ratio) corresponding to a component liquid mixing ratio (default mixing ratio, target mixing ratio) for adjusting a processing liquid having a target component concentration (target value). . Based on the set flow value, the flow controllers 37 to 39 are controlled (step S5).

  Therefore, when the control device 30 opens all the component liquid valves 34 to 36 at the same time, the respective component liquids flow into the mixing section 26 in the form of manifold piping via the component liquid supply pipes 31 to 33 according to the set flow rate values. Merge (step S6). Thereby, the mixed liquid in which a plurality of component liquids are mixed at the predetermined mixing ratio is adjusted in the middle of the piping, and the adjusted mixed liquid is charged into the processing liquid tank 10 through the processing liquid charging pipe 25.

  The control device 30 monitors the output signal of the replenishment stop liquid level sensor 54 and determines whether or not the liquid level has reached the replenishment stop height (step S7). If the liquid level does not reach the replenishment stop height (step S7: NO), the supply of each component liquid is continued while controlling the flow rate of each component liquid (step S5) (step S6). When the liquid level rises due to the replenishment of the mixed liquid and reaches the replenishment stop height (step S7: YES), the control device 30 closes the component liquid valves 34 to 36 all at once (step S8) and stops the replenishment of the mixed liquid. To do.

  On the other hand, if any of the component concentrations is less than the lower control limit, that is, if there is an insufficient component (step S2: YES), the control device 30 calculates the total amount of liquid mixture (total supply amount) to be replenished. (Step S9). Specifically, the control device 30 obtains the current liquid level height based on the output signals of the intermediate liquid level sensors L1 to Ln. The control device 30 further determines the total amount of liquid to be replenished (total replenishment amount X) to raise the liquid level to the replenishment stop liquid level based on the difference between the current liquid level and the replenishment stop liquid level. Is calculated. When the horizontal cross-sectional area in the treatment liquid storage space inside the treatment liquid tank 10 can be regarded as the same between the replenishment liquid level height and the replenishment stop liquid level height, the current liquid level height and the replenishment stop liquid level height The total replenishment amount X can be obtained by multiplying the difference between the two by the horizontal sectional area.

  Further, when the processing liquid is stored in the processing liquid tank 10 up to the replenishment stop liquid level, the total amount of the processing liquid existing in the processing liquid tank 10 (total storage amount Z) is obtained in advance. In this case, the treatment liquid is present not only in the treatment liquid tank 10 but also in pipes and devices connected to the treatment liquid tank 10, but here the amount does not affect the concentration calculation. The amount of the treatment liquid may be ignored. However, in the case where the influence cannot be ignored, the amount of the processing liquid present in the piping and equipment connected to the processing liquid tank 10 may be added to the total storage amount Z.

  When the total replenishment amount X and the total storage amount Z are obtained in this way, the control device 30 further calculates the individual replenishment amount of each component liquid (step S10). At this time, for the component liquid corresponding to the insufficient component (ammonia water when the ammonia concentration is insufficient, or hydrogen peroxide solution when the hydrogen peroxide concentration is insufficient), the default mixing when adjusting the treatment liquid 14 is performed. A replenishment amount with a larger ratio than the ratio according to the ratio is calculated. For example, the control device 30 may obtain the individual replenishment amount of each component liquid according to the following procedure.

Procedure 1: An additional replenishment amount ΔH of the component liquid (for example, component liquid 1) to be replenished to compensate for the insufficient concentration of the insufficient component in the residual liquid (liquid amount Z-X) in the processing liquid tank 10 is obtained.
Procedure 2: An amount obtained by subtracting the additional replenishment amount ΔH from the total replenishment amount X (X−ΔH) is apportioned at a predetermined mixing ratio, and the basic individual replenishment amount H ₁ and component liquid 2 (first liquid) of component liquid 1 (first chemical liquid) basic individual supply amount of H ₂ 2 _chemical), and component liquid 3 (Request basic individual replenishment amount H ₃ of pure water). H ₁ + H ₂ + H ₃ = X−ΔH.

Procedure 3: The basic individual replenishment amount H ₁ of component liquid 1 is corrected by the additional replenishment amount H, and the individual replenishment amount H ₁ + ΔH after correction of component liquid 1 is obtained. For the component liquids 2 and 3 whose component concentrations are not insufficient, the basic individual replenishment amounts H ₂ , H ₃ and D are used as they are.
When the individual replenishment amount is determined in this way, the control device 30 sets the flow rate values of the component liquids 1 to 3 so that the flow rate ratio corresponds to the ratio of the individual replenishment amount (step S11). In accordance with the set flow rate value, the processes of steps S5 to S8 are performed. That is, the flow rate controllers 37 to 39 are controlled with the set flow rate value (step S5), and the component liquid valves 34 to 36 are opened all at once (step S6). Thereby, the component liquids 1-3 are mixed and mixed (mixing in the middle of piping) in the mixing part 26, and are supplied to the process liquid tank 10 through the process liquid injection pipe 25 with the form of a liquid mixture.

  At this time, since the mixing ratio of the insufficient component is larger than the predetermined mixing ratio of the component in the processing liquid 14, the concentration of the insufficient component in the processing liquid tank 10 approaches the target value as the supply of the mixed liquid proceeds. The control device 30 monitors the output of the replenishment stop liquid level sensor 54, and when the replenishment stop liquid level sensor 54 detects the liquid level of the processing liquid 14, that is, the liquid level in the processing liquid tank 10 rises and replenishes. When the stop liquid level is reached (step S7: YES), the component liquid valves 34 to 36 are closed simultaneously (step S8). Thereby, supply of all the component liquids 1-3 is stopped simultaneously. At this time, the processing liquid 14 in the processing liquid tank 10 has a value in which all components approximate the target value (a value within a predetermined allowable range centered on the target value).

  As described above, in this embodiment, even if the liquid level in the processing liquid tank 10 is not lowered to the replenishing liquid level, the replenishment of the processing liquid 14 is detected when any component concentration is detected to be insufficient. Is executed. At this time, the current liquid level is detected by the intermediate liquid level sensors L1 to Ln, and the total replenishment amount required to raise the liquid level to the replenishment stop liquid level is calculated based on the detection result. Further, a plurality of component liquids are mixed at a mixing ratio in which the mixing ratio of the deficient components is higher than the predetermined mixing ratio, and the liquid mixture (processing liquid) for the calculated total supply amount is supplied to the processing liquid tank 10. . In this way, the component liquid corresponding to the insufficient component is mixed with the other component liquids and replenished to the treatment liquid tank 10 in the form of a mixed liquid, thereby reducing the component concentration of the insufficient component to a concentration within an allowable range near the predetermined value. Can be restored.

  Moreover, in this embodiment, since the flow rate ratio ratio of the plurality of component concentrations is set larger than the predetermined flow rate ratio so as to supplement the component concentration of the insufficient component, the supply of the plurality of component liquids is started simultaneously, At the same time, the concentration of the insufficient component can be corrected by stopping the supply. Thereby, the replenishment of the deficient component is not carried out as a single liquid at any point of time, but in the form of a mixed liquid throughout. Accordingly, since the insufficient component can be supplemented by replenishing the mixed liquid approximate to the mixing ratio of the processing liquid 14 in the processing liquid tank 10, the concentration unevenness in the processing liquid tank 10 accompanying the replenishment of the insufficient component is minimized. Can be suppressed. Thereby, even during the period when the component concentration of the processing liquid 14 in the processing liquid tank 10 is being corrected, the processing liquid can be supplied to the substrate processing unit 5 and the processing of the substrate W can be continued. Further, even if a stable period (a standby period during which the substrate W is not processed) is provided in order to eliminate the density unevenness, such a stable period may be very short. Therefore, in any case, productivity related to the processing of the substrate W can be improved.

In addition, since the processing liquid may be replenished before the liquid level in the processing liquid tank 10 drops to the replenishing liquid level, the total amount of liquid supplied during replenishment can be reduced in this case. Therefore, there is an advantage that the temperature change at the time of replenishing the processing liquid is suppressed. Thereby, the temperature adjustment of the process liquid by the temperature controller 16 can be performed effectively.
A description will be given of how to obtain the additional replenishment amount ΔH (liter).

As an example, DHF (dilute hydrofluoric acid) is prepared by mixing c% hydrofluoric acid (HF) and pure water (DIW) at a volume ratio A: B (usually A <B), and this is used as a treatment liquid. The case will be described.
Since the component concentration measuring device 20 generally outputs the concentration value in wt% w (wt%), the specified concentration Y of DHF is expressed in wt% as the following formula (1). However, the specific gravity of c% hydrofluoric acid is expressed as d _HF (g / cm ³ ), and the specific gravity of pure water is expressed as d _DIW (g / cm ³ ).

When the specific gravity d _HF of c% hydrofluoric acid and the specific gravity d _DIW of pure water are both regarded as “1”, the following formula (2) is obtained. In the following description, it is assumed that d _HF = d _DIW = 1.

  A value E (wt%) below the lower control limit where the component concentration of hydrofluoric acid is F (wt%) lower than the specified concentration Y (wt%) when the liquid volume in the treatment liquid tank 10 is (ZX) (liter) In order to obtain the additional replenishment amount ΔH (liter) of c% hydrofluoric acid to be replenished in order to return the hydrofluoric acid concentration to the specified concentration Y, the following equation (3) may be solved. Thus, it can be seen that the additional replenishment amount ΔH (liter) is given by the following formula (4). Y ′ (wt%) is a value representing the concentration of c% hydrofluoric acid in weight%.

That is, the deficient hydrofluoric acid concentration (YE) (wt%) in the residual liquid is multiplied by the residual liquid amount (ZX) (liter), and this is replenished with the hydrofluoric acid concentration Y 'and the prescribed hydrofluoric acid concentration. By dividing by the difference from Y, the additional replenishment amount ΔH (liter) can be obtained.
This example is a case in which an additional replenishment amount ΔH of a chemical component is obtained for a processing solution in which one chemical component and pure water are mixed, but a process prepared by mixing two or more chemical components and pure water. The additional replenishment amount ΔH can be similarly determined for the liquid.

Specifically, when the treatment liquid is prepared by mixing the first chemical component, the second chemical component, and pure water, the component concentration of the first chemical component is below the control lower limit, and the component concentration of the second chemical component Is a value within the density management range (allowable density range). In this case, the additional replenishment amount ΔH ₁ may be obtained for the first chemical component according to the above example. Further, the change in the concentration of the second chemical solution component caused by adding the first chemical solution component by the additional replenishment amount ΔH ₁ is examined, and when the concentration of the second chemical solution component is outside the concentration management range, the second seeking additional replenishment amount [Delta] H ₃ additional replenishment amount [Delta] H ₂ and / or pure water of the chemical components may be added to these basic individual supply amount _{H 1, H 2, H 3} .

FIG. 3 is a flowchart for explaining another example of the component liquid supply operation in the processing liquid supply apparatus. In FIG. 3, steps in which processing similar to the steps shown in FIG. 2 is performed are denoted by the same reference numerals as in FIG. 2.
In this operation example, when there is an insufficient component (step S2: YES), the control device 30 obtains a required supply time required for supplying a plurality of component liquids in the form of a mixed liquid (step S15). The required supply time can be obtained, for example, by dividing the individual replenishment amount of any component liquid (step S10) by the flow rate value of the component liquid (step S11). It can also be obtained by dividing the total replenishment amount (step S9) by the sum of the respective flow rate values of the plurality of component liquids (total flow rate value).

  When the supply of a plurality of component liquids is started (step S6), the control device 30 measures the elapsed time from the start of the supply and monitors whether the elapsed time has reached the required supply time (step). S16). The control device 30 satisfies either of the following conditions: the elapsed time reaches the required supply time (step S16), or the liquid level in the processing liquid tank 10 reaches the replenishment stop liquid level (step S7). The supply of a plurality of component liquids is continued until When the elapsed time reaches the supply elapsed time or the liquid level in the processing liquid tank 10 reaches the replenishment stop liquid level, the control device 30 closes the component liquid valves 34 to 36 all at once (step S8). ), Replenishment operation is terminated.

There is no shortage in component concentration (step S2: NO), and when the component liquid is supplied in response to the liquid level being lowered to the replenishment liquid level (step S3: YES), the required supply time is not calculated. The determination in step S16 is negative, and the supply of the component liquid is controlled exclusively based on the output of the replenishment stop liquid level sensor 54.
Thus, in this operation example, when the component concentration is insufficient, the required supply time of the mixed liquid for the total replenishment amount is calculated in advance, and the supply of the component liquid is stopped when the required supply time is reached. Accordingly, each component liquid can be accurately replenished to the treatment liquid tank 10 in the form of a mixed liquid by an amount corresponding to the individual replenishment amount calculated to compensate for the deficient component. For example, if the substrate processing operation in the substrate processing unit 5 is continued even during the processing liquid supply operation, the processing liquid 14 in the processing liquid tank 10 is consumed. In this case, if the supply of the component liquid is continued until the replenishment stop liquid level is reached, the result is that each component liquid is supplied in excess of the calculated individual replenishment amount. At this time, the component concentration corresponding to the component liquid having a mixing ratio higher than the predetermined mixing ratio may be higher than the predetermined component concentration (target value). Similarly, the component concentration corresponding to the component liquid having a mixing ratio lower than the predetermined mixing ratio may be lower than the predetermined component concentration (target value). Therefore, this problem can be avoided by executing supply control based on the required supply time.

FIG. 4 is a flowchart for explaining an example of the component liquid supply operation in the processing liquid supply apparatus according to the second embodiment of the present invention. In the description of this embodiment, reference is again made to FIG. In FIG. 4, steps corresponding to the respective steps shown in FIG. 2 are given the same reference numerals as those in FIG. 2.
In this embodiment, as shown by a two-dot chain line in FIG. 1, a processing liquid (mixed liquid) introduced into the processing liquid tank 10 through the processing liquid input pipe 25 in the middle of the processing liquid input pipe 25. ) Integrated flow meter 28 for measuring the integrated flow rate (actual total replenishment amount, input amount) is provided. The measurement result by the integrated flow meter 28 is input to the control device 30.

  Referring to FIG. 4, in this embodiment, when the supply of a plurality of component liquids is started (step S <b> 6), the control device 30 monitors the output of the integrating flow meter 28. That is, the control device 30 monitors whether or not the integrated flow rate (actual total supply amount) from the start of supply has reached the calculated total supply amount (step S9) (step S21). The controller 30 determines whether the integrated flow rate reaches the calculated total replenishment amount (step S21) or whether the liquid level in the processing liquid tank 10 reaches the replenishment stop liquid level (step S7). The supply of a plurality of component liquids is continued until When the integrated flow rate reaches the calculated total replenishment amount or the liquid level in the processing liquid tank 10 reaches the replenishment stop liquid level, the control device 30 closes the component liquid valves 34 to 36 all at once ( Step S8), the supply operation is terminated.

When there is no shortage in any of the component concentrations (step S2: NO) and the component liquid is replenished in response to the liquid level being lowered to the replenishment liquid level (step S3: YES), the total replenishment amount is calculated. Accordingly, the determination in step S21 is negative, and the supply of the component liquid is controlled exclusively based on the output of the replenishment stop liquid level sensor 54.
When the component concentration is insufficient, the replenishment total amount is calculated in advance, so that the supply of the component liquid is stopped when the integrated flow rate reaches the replenishment total amount. Accordingly, each component liquid can be accurately replenished to the treatment liquid tank 10 in the form of a mixed liquid by an amount corresponding to the individual replenishment amount calculated to compensate for the deficient component. Therefore, the same effect as in the operation example of FIG. 2 can be achieved.

  Instead of interposing the integrated flow meter 28 in the processing liquid input pipe 25, a configuration may be adopted in which an integrated flow meter (individual integrated flow meter) is interposed in each of the plurality of component liquid supply pipes 31 to 33. In this case, when the integrated flow rate of the component liquid measured by the individual integrated flow meter reaches the individual replenishment amount (calculated value in step S10), the component liquid valves 34 to 36 corresponding to the component liquid are closed. That's fine. However, in this configuration, since a plurality of integrated flow meters are required, the above-described configuration in which one integrated flow meter 28 is interposed in the processing liquid input pipe 25 is more advantageous in terms of cost.

FIG. 5 is a conceptual diagram for explaining a configuration of a processing liquid supply apparatus according to the third embodiment of the present invention. In FIG. 5, parts corresponding to those shown in FIG. 1 are given the same reference numerals as those in FIG.
In this embodiment, in the component liquid supply pipe 31 between the supply source 41 of the component liquid 1 (first chemical liquid) and the mixing unit 26, a regulator (pressure regulator) 61, in order from the component liquid supply source 41 side, An automatic flow control valve 64, an individual integrated flow meter 67, and a component liquid valve 34 are interposed. In addition, in the component liquid supply pipe 32 between the component liquid 2 (second chemical liquid) supply source 42 and the mixing unit 26, in order from the component liquid supply source 42 side, a regulator (pressure regulator) 62, automatic flow rate adjustment. A valve 65, an individual integrated flow meter 68, and a component liquid valve 35 are interposed. Similarly, in the component liquid supply pipe 33 between the component liquid 3 (pure water: DIW) supply source 43 and the mixing unit 26, in order from the component liquid supply source 43 side, a regulator (pressure regulator) 63, automatic A flow rate adjusting valve 66, an individual integrating flow meter 69, and a component liquid valve 36 are interposed.

  The regulators 61 to 63 are supply pressure adjusting devices that adjust the supply pressure of the component liquids 1, 2, and 3 to a predetermined equal pressure. The automatic flow control valves 64 to 66 can be configured by needle valves with actuators such as motors, for example, and the opening degree is controlled by the control device 30. By controlling the opening, each flow rate in the component liquid supply pipes 31 to 33 can be individually controlled. Since the supply pressures of the component liquids 1, 2 and 3 are equalized by the regulators 61 to 63, the ratio of the opening amounts of the automatic flow rate adjusting valves 64 to 66 is the flow rate ratio of the component liquids passing through the component liquid supply pipes 31 to 33. Is equal to The individual integrated flow meters 67 to 69 integrate the flow rates of the component liquids flowing through the component liquid supply pipes 31 to 33, and measure the individual integrated flow rates (actual individual replenishment amounts) of the individual component liquids. The measurement results of these individual integrated flow meters 67 to 69 are input to the control device 30.

  FIG. 6 is a flowchart for explaining an example of the component liquid replenishment operation of the processing liquid supply apparatus of FIG. In FIG. 6, the same steps as those shown in FIG. 2 are denoted by the same reference numerals as those in FIG. 2. The operation when there is no deficient component (step S2: NO) is substantially the same as in FIG. 2 (steps S3 to S8). However, in the case of the first embodiment, the flow rate is controlled by the flow rate controllers 37 to 39, whereas in this embodiment, the flow rate is controlled by setting the opening degree of the automatic flow rate adjusting valves 64 to 66. The ratio (opening ratio) is set to a predetermined value (step S4A), and each of the automatic flow control valves 64 to 66 is controlled so as to be the set opening ratio (step S5A).

On the other hand, when there is an insufficient component (step S2: YES), the calculation of the total replenishment amount (step S9) and the calculation of the individual replenishment amount of the component liquid (step S10) are performed, and further according to the ratio of the individual supply flow rate Thus, the flow ratio of the plurality of component liquids is set (step S31). Specifically, the opening degree of the automatic flow control valves 64 to 66 is set according to the ratio of the individual supply flow rates.
The control device 30 controls the automatic flow control valves 64 to 66 according to the set opening degree (step S32). The control device 30 monitors the outputs of the individual integrated flow meters 67 to 69, and the individual integrated flow rates (actually measured values from the start of supply) for each of the component liquids 1 to 3 (first chemical solution, second chemical solution and pure water). It is determined whether or not the calculated individual replenishment amount (calculated value in step S9) has been reached (steps S33, S36, S39). For component liquids for which the individual integrated flow rate has not reached the individual replenishment amount (calculated value), the corresponding component liquid valves 34 to 36 are opened in order to supply the component liquid (steps S34, S37, S40). For the component liquid whose individual integrated flow rate has reached the individual replenishment amount (calculated value), the corresponding component liquid valves 34 to 36 are closed in order to stop the supply of the component liquid (steps S35, S38, S41). Thereby, each component liquid can be supplied by each individual replenishment amount (calculated value). Of course, the supplied component liquids are merged in the mixing unit 26 to become a mixed liquid, and the mixed liquid is supplied into the processing liquid tank 10 through the processing liquid input pipe 25. When the supply of all the component liquids is stopped (step S42: YES), the replenishment operation ends.

  Since the determination and control in steps S33 to S42 are performed at a sufficiently high speed, supply of a plurality of component liquids is started simultaneously. In addition, since the supply of a plurality of component liquids is started simultaneously at a flow rate ratio corresponding to the ratio of the individual replenishment amounts (calculated values) of the plurality of component liquids, the individual integrated flow rates of the plurality of component liquids (actual individual replenishment amounts) ) Will reach each individual replenishment amount substantially simultaneously. Accordingly, the supply of the plurality of component liquids is stopped substantially simultaneously. Therefore, the plurality of component liquids are supplied to the processing liquid tank 10 in a mixed liquid state from beginning to end. Therefore, it is possible to effectively suppress or prevent the occurrence of uneven concentration in the processing liquid tank 10.

FIG. 7 is a conceptual diagram for explaining a configuration of a processing liquid supply apparatus according to the fourth embodiment of the present invention. In FIG. 7, the same reference numerals as those in FIG. 5 are given to the corresponding parts of the respective parts shown in FIG. This embodiment is different in that the regulators 61 to 63 are not provided.
FIG. 8 is a flowchart for explaining an example of the processing liquid supply operation in the processing liquid supply apparatus of FIG. In FIG. 8, steps in which the same processes as those in FIG. 6 are performed are denoted by the same reference numerals as in FIG. 6. In this embodiment, since the supply pressures of the plurality of component liquids are not controlled to be equal, it is difficult to control the flow rate ratio (mixing ratio) by adjusting the opening degree of the automatic flow rate adjusting valves 64 to 66. . Therefore, the automatic flow rate adjusting valves 64 to 66 are controlled to a predetermined opening degree set in advance so that a plurality of component liquids constituting the processing liquid 14 are mixed at a predetermined mixing ratio in the mixing unit 26 (step S45). ). That is, the process in step S45 is substantially the same as the process in step S4A. Therefore, it is not always necessary to use the automatic flow rate adjusting valves 64 to 66, and a flow rate adjusting valve capable of manually adjusting the opening degree may be used instead.

  The processing after step S33 is the same as in FIG. 6, but the timing of stopping the supply of component liquids is different from that in the third embodiment. That is, in this embodiment, since each component liquid is supplied at each predetermined flow rate regardless of the component concentration, the supply stop timing is lower than the supply stop timing of other component liquids for the component liquid corresponding to the insufficient component. Also late. Therefore, although it is a short time, the component liquid of the insufficient component may be supplied to the processing liquid tank 10 in a single liquid state. Due to the component liquid supplied to the processing liquid tank 10 in a single liquid state in a short time, there is a possibility that uneven concentration occurs in the processing liquid tank 10. However, since the processing liquid in the state of the mixed liquid is first supplied to the processing liquid tank 10, the component liquid in a single liquid state is obtained in a state where a sufficient amount of the processing liquid 14 exists in the processing liquid tank 10. It is only supplied for a very short time. Therefore, a stabilization time for eliminating the density unevenness is unnecessary or even if necessary. Therefore, the productivity of substrate processing can be improved.

  As mentioned above, although four embodiment of this invention was described, this invention can also be implemented with another form. For example, in the above-described embodiment, an example in which three component liquids are mixed to prepare a treatment liquid has been described, but of course, the component liquids constituting the treatment liquid may be two types, or four or more types. There may be. Furthermore, in the above-described embodiment, the configuration including the temperature controller 16 for adjusting the temperature of the processing liquid has been described. However, the present invention may be applied to a configuration that does not include such a temperature controller. .

In the above-described embodiment, the configuration in which the processing liquid used for substrate processing is collected and reused is taken as an example. However, this configuration is not used for the configuration in which the used processing liquid is not collected and reused. The invention may be applied.
Furthermore, in the above-described embodiment, the configuration for detecting the liquid level in the processing liquid tank 10 is taken as an example, but the amount of the processing liquid in the processing liquid tank 10 does not need to be specified by the liquid level, For example, it can be replaced by a configuration in which the liquid pressure at the inner bottom surface of the processing liquid tank 10 is detected or the weight of the processing liquid in the processing liquid tank 10 is measured.

  In the above-described embodiment, when the liquid level in the processing liquid tank 10 reaches the replenishment liquid level, a plurality of component liquids are mixed at a predetermined mixing ratio. Depending on the deviation between the component concentration (measured value) measured by the concentration measuring device 20 and the target value of each component concentration, the component liquid may be mixed at a mixing ratio different from the predetermined mixing ratio. In this case, the individual replenishment amount of each component liquid is obtained based on the total replenishment amount (the liquid amount from the replenishment liquid level to the replenishment stop liquid level), and each component liquid is supplied according to this individual replenishment amount. Good. That is, the same operation as when the component liquid concentration falls below the lower control limit may be executed.

  Furthermore, in the above-described embodiment, the replenishment operation is performed to correct the component concentration of the treatment liquid when any component concentration falls below the control lower limit. However, any component concentration exceeds the control upper limit. Even when the rotation is performed, the component concentration correction of the processing liquid may be performed by the same replenishment operation. Of course, in this case, the replenishment amount ratio of the component liquid corresponding to the excessively concentrated component is set lower than the predetermined mixing ratio.

  In addition, various design changes can be made within the scope of matters described in the claims.

DESCRIPTION OF SYMBOLS 1 Chemical solution cabinet 2 Processing apparatus main body 3 Substrate processing apparatus 5 Substrate processing part 6 Processing cup 7 Spin chuck 8 Processing liquid nozzle 9 Processing liquid valve 10 Processing liquid tank 11 Mixing mechanism 12 Supply mechanism 13 Processing liquid quantity measuring mechanism 14 Processing liquid 15 Processing Liquid supply pipe 16 Temperature controller 17 Pump 18 Filter 20 Component concentration measuring device 21 Branch position 22 Processing liquid feedback pipe 23 Feedback valve 25 Processing liquid input pipe 25 This processing liquid input pipe 26 Mixing unit 28 Accumulated flow meter 30 Controller 31 to 31 33 Component liquid supply pipe 34 to 36 Component liquid valve 37 to 39 Flow rate controller 41 to 43 Component liquid supply source 50 Liquid level sensor 51 Lower limit liquid level sensor 52 Upper limit liquid level sensor 53 Replenishment liquid level sensor 54 Replenishment stop liquid level sensor L1 ~ Ln Intermediate liquid level sensor 61 ~ 63 Regulator 64 ~ 66 Automatic flow control valve 67 ~ 6 9 Individual integrated flow meter W Substrate

Claims (11)

A processing liquid tank for storing a processing liquid to be supplied to a processing unit for performing processing with the processing liquid on the processing target;
A processing liquid input path for supplying the processing liquid to the processing liquid tank;
Mixing means for combining and mixing a plurality of component liquids constituting the processing liquid in the middle of the processing liquid charging path;
Component concentration measuring means for respectively measuring the component concentrations of a plurality of components contained in the treatment liquid in the treatment liquid tank;
Component liquid supply amount calculating means for calculating the supply amount of each component liquid according to the component concentration measured by the component concentration measuring means and the target value of the component concentration;
Supply control means for supplying a mixed liquid obtained by mixing to the processing liquid tank while mixing a plurality of component liquids by the manual mixing according to the component liquid supply amount calculated by the component liquid supply amount calculating means. ,
A processing liquid amount detecting means for detecting a processing liquid amount in the processing liquid tank,
The component liquid supply amount calculation means includes:
Based on the amount of processing liquid detected by the processing liquid amount detection means, a total supply amount calculating means for obtaining the total amount of processing liquid to be supplied to the processing liquid tank;
The individual supply amount for calculating the individual supply amount of each component liquid according to the total supply amount obtained by the total supply amount calculating unit, the component concentration measured by the component concentration measuring unit, and the target value of the component concentration A processing liquid supply apparatus, comprising: a computing means .   The individual supply amount calculation means is configured to supply a component liquid to be replenished to the remaining liquid in the processing liquid tank in order to compensate for the insufficient concentration of the insufficient component whose component concentration measured by the component concentration measurement means is insufficient. The processing liquid supply apparatus according to claim 1, wherein an additional replenishment amount is obtained, and an individual supply amount of each component liquid is calculated using the additional replenishment amount.   The individual supply amount calculating means obtains a basic individual replenishment amount of each component liquid by apportioning an amount obtained by subtracting the additional replenishment amount from the total replenishment amount by a predetermined mixing ratio, and adds the basic individual replenishment amount of the insufficient component The processing liquid supply apparatus according to claim 2, wherein an individual replenishment amount of the deficient component is calculated by correcting with a replenishment amount. The mixing means includes individual flow rate control means for individually controlling the supply flow rates of a plurality of component liquids,
The supply control means controls the individual flow rate control means so that the plurality of component liquids are mixed at a mixing ratio corresponding to each component liquid supply amount calculated by the component liquid supply amount calculation means. The processing liquid supply apparatus according to any one of claims 1 to 3 . A charge stop level detecting means for detecting that the amount of the process liquid in the process liquid tank has reached a predetermined charge stop level;
The total supply amount calculation means supplies necessary to increase the amount of the processing liquid in the processing liquid tank to the charging stop level when the concentration of any of the processing liquids is less than a predetermined control lower limit. The total amount is calculated,
The supply control unit simultaneously stops the supply of the plurality of component liquids in response to the detection of the input stop level detecting unit that the amount of the processing liquid in the processing liquid tank has reached the input stop level. The processing liquid supply apparatus according to claim 4, wherein The total supply amount calculating means is necessary to increase the amount of the processing liquid in the processing liquid tank to a predetermined charging stop level when any of the component concentrations of the processing liquid becomes less than a predetermined control lower limit. To calculate the total supply,
The supply control means includes a supply time measurement means for measuring the supply time of the mixed liquid, and in response to the supply time measurement means measuring a time corresponding to the total supply amount, the plurality of component liquids The processing liquid supply apparatus according to claim 4 , wherein the supply is stopped simultaneously. Further comprising a total supply amount measuring means for measuring the total supply amount of the mixed liquid,
In response to the total supply amount of the liquid mixture measured by the total supply amount measurement unit reaching the total supply amount calculated by the total supply amount calculation unit, the supply control unit supplies the plurality of component liquids. The processing liquid supply apparatus according to claim 4 , which stops at the same time. It further includes a plurality of individual supply amount measuring means for measuring the supply amounts of the plurality of component liquids before mixing,
The supply control unit is configured to stop the supply of each component liquid when the supply amount of each component liquid measured by the individual supply amount measurement unit reaches a calculation value by the component liquid supply amount calculation unit. The processing liquid supply apparatus according to claim 4 . It further includes a plurality of individual supply amount measuring means for measuring the supply amounts of the plurality of component liquids before mixing,
The mixing means joins the plurality of component liquids in the processing liquid supply path at a flow rate ratio corresponding to a target mixing ratio of the plurality of component liquids constituting the processing liquid,
The supply control unit individually stops the supply of the plurality of component liquids when the supply amount of each component liquid measured by the individual supply amount measurement unit reaches a calculation value by the component liquid supply amount calculation unit. The processing liquid supply apparatus according to claim 1, wherein Supplying the processing liquid stored in the processing liquid tank to a processing unit for processing the processing target with the processing liquid;
Measuring each of the component concentrations of a plurality of components contained in the treatment liquid in the treatment liquid tank;
A component liquid supply amount calculating step of calculating each supply amount of a plurality of component liquids constituting the treatment liquid according to the measured component concentration and a target value of the component concentration;
In accordance with the calculated component liquid supply amount, the mixed liquid obtained by mixing is mixed while the plurality of component liquids are joined and mixed in the middle of the processing liquid charging path for supplying the processing liquid to the processing liquid tank. Supplying the liquid tank ;
Detecting the amount of the processing liquid in the processing liquid tank,
The component liquid supply amount calculation step includes:
A step of obtaining a total amount of processing liquid to be supplied to the processing liquid tank based on the detected amount of the processing liquid;
A processing liquid supply method, comprising: calculating an individual supply amount of each component liquid in accordance with the determined total supply amount, the measured component concentration, and a target value of the component concentration . Wherein as said plurality of component liquid at the calculated mixing ratio corresponding to each component solution supply amount is mixed, further comprising the step of individually controlling the supply flow rate of the plurality of component liquid, according to claim 1 0, wherein Process liquid supply method.

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