JP2016072296A - Processing liquid supply device and filter deterioration detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a processing liquid supply device capable of supplying a clean processing liquid while suppressing an increase in cost.SOLUTION: A processing liquid supply device 3 for supplying a chemical to a substrate processing part 2 includes: circulation piping 15 in which the chemical supplied from a chemical tank 10 is circulated; a first filter 19 for circulation which filters the chemical circulating in the circulation piping 15; first branch piping 17 which is separate piping from the circulation piping 15; a first filter 21 for detection, which filters the chemical circulating in the first branch piping 17; a first flowmeter 25; and a CPU. The chemical supplied from the chemical tank 10 is simultaneously supplied to the circulation piping 15 and the first branch piping 17. The first flowmeter 25 and the CPU detect a change in a pressure loss of the first filter 21 for detection and on the basis of a detection result, the CPU determines deterioration of the first filter 19 for circulation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a processing liquid supply apparatus that supplies a processing liquid to a substrate processing unit that processes a substrate to be processed, and a filter deterioration detection method that detects deterioration of a filter that filters the processing liquid. Examples of substrates to be processed include semiconductor wafers, glass substrates for liquid crystal display devices, plasma display substrates, FED (Field Emission Display) substrates, optical disk substrates, magnetic disk substrates, magneto-optical disk substrates, photo Substrates such as a mask substrate, a ceramic substrate, and a solar cell substrate are included.

  Patent Document 1 below discloses a cleaning apparatus for cleaning a substrate. The cleaning device includes a circulation line for circulating the cleaning liquid to the cleaning tank. A filter such as a chemical solution filter and a pressure gauge are provided in the middle of the piping for the circulation line. The filter filters the cleaning liquid. The pressure gauge measures the pressure difference before and after the filter in the pipe. When the filtering ability of the filter deteriorates due to adhesion of dust or the like, the pressure difference between the front and rear of the filter in the pipe increases. When the pressure difference exceeds a certain value, it is determined that the filter replacement time has come, and the filter is replaced with a new one.

JP 2002-246357 A

  In recent years, miniaturization of devices formed on a substrate has progressed. As a result, fine particles such as a small amount of dust cause device defects. In order not to cause defects in the device, it is necessary to reliably remove particles from the processing liquid and strictly control the cleanliness of the processing liquid. Accordingly, it is necessary to detect the deterioration of the filter with high accuracy so that the particles do not pass through the filter.

A change in the pressure loss of the processing liquid passing through the filter due to the deterioration of the filter is relatively small. Therefore, as in Patent Document 1, the method of detecting the deterioration of the filter by simply measuring the pressure difference before and after the filter in the piping for the circulation line has insufficient deterioration detection accuracy, and the cleanliness of the processing liquid May not be fully managed.
On the other hand, using a relatively expensive device such as a particle counter, it is conceivable to detect the deterioration of the filter by strictly measuring the number of particles in the processing liquid after being filtered by the filter. This measure may increase costs.

Accordingly, one of the objects of the present invention is to provide a processing liquid supply apparatus capable of supplying a clean processing liquid while suppressing an increase in cost.
Another object of the present invention is to provide a filter deterioration detection method capable of accurately detecting deterioration of a filter while suppressing an increase in cost.

  The invention described in claim 1 for achieving the above object is a processing liquid supply device (3) for supplying a processing liquid to the substrate processing section (2), wherein the processing liquid supply section (10, 10A, 11, 11A), the first pipe (15, 16) through which the processing liquid flows, the flow filter (19, 20) for filtering the processing liquid flowing through the first pipe, The second pipe (17, 18, 85) through which the processing liquid supplied from the processing liquid supply unit flows and the second pipe through the second pipe are different from the first pipe. A filter for detection (21, 22) for filtering the processing liquid, and the first and second pipes are supplied with the processing liquid supplied from the processing liquid supply unit at the same time, The processing liquid supply device includes the detection filter in the second pipe. Pressure loss change detecting means (25, 26, 66, 81, 82) for detecting a change in pressure loss, and deterioration determining means for determining deterioration of the flow filter based on the detection result of the pressure loss change detecting means. (66).

The numbers in parentheses represent corresponding components in the embodiments described later, but are not intended to limit the scope of the claims to the embodiments. The same applies hereinafter.
The “pressure loss of the detection filter in the second pipe” refers to the amount of energy lost when the processing liquid flowing through the second pipe passes through the second filter. In this specification, the “pressure loss of the detection filter in the second pipe” may be simply referred to as “pressure loss of the detection filter”.

  According to this configuration, the processing liquid supplied from the common processing liquid supply unit is simultaneously supplied to the first and second pipes. The distribution filter filters the processing liquid flowing through the first pipe, and the detection filter filters the processing liquid flowing through the second pipe. Therefore, the processing liquid from the common processing liquid supply unit flows through the distribution filter and the detection filter at the same time. Thus, the degree of deterioration (deterioration degree) of the distribution filter and the detection filter is related to each other. Therefore, it is possible to accurately determine the deterioration of the circulation filter based on the detection result of the change in the pressure loss of the detection filter. Therefore, it is possible to replace the distribution filter at an appropriate time, and thereby the processing liquid supplied to the substrate processing unit can be kept clean.

Moreover, since it is not necessary to provide a device for accurately detecting the deterioration of the filter, an increase in cost can be suppressed.
Thereby, it is possible to supply a clean processing liquid while suppressing an increase in cost.
The invention according to claim 2 is the processing liquid supply apparatus according to claim 1, wherein the hole diameters (d1, d2) of the detection filter are smaller than the hole diameters (D1, D2) of the flow filter.

  The hole diameter of the filter refers to a diameter of a circle having a radius as an average value of distances from the center of gravity of the hole of the filter to the edge of the hole when viewed from the thickness direction of the filter. That is, when the hole is circular as viewed from the thickness direction of the filter, the hole diameter corresponds to the diameter of the circle. Further, when the holes are square as viewed from the thickness direction of the filter, the hole diameter is longer than the length of one side of the square and shorter than the length of the diagonal line of the square.

According to this configuration, the hole diameter of the detection filter is smaller than the hole diameter of the circulation filter. Therefore, as the hole diameter of the detection filter becomes smaller, the detection filter is likely to be clogged, and the change in the pressure loss of the detection filter increases.
Therefore, it is possible to accurately detect the deterioration of the circulation filter based on the change in the pressure loss of the detection filter.

The invention according to claim 3 is the processing liquid supply device according to claim 1 or 2, wherein the filtration area (r1, r2) of the detection filter is smaller than the filtration area (R1, R2) of the flow filter. It is.
The filtration area is a surface area of a portion where the chemical solution can be filtered in the filter.
According to this configuration, the detection filter has a smaller filtration area than the distribution filter. As the filtration area decreases, the detection filter becomes cheaper. Therefore, it is possible to satisfactorily detect deterioration of the distribution filter while suppressing an increase in cost.

Invention of Claim 4 is provided so that the flow volume (j1, j2, J1, J2) of the processing liquid per unit filtration area may become equal to the distribution filter and the detection filter. It is a process liquid supply apparatus as described in any one of Claims 1-3.
Here, the unit filtration area is a filtration area per unit area (for example, 1 m ² ).
According to this configuration, since the flow rates of the processing liquid per unit filtration area of the detection filter and the distribution filter are equal to each other, the degrees of deterioration of the distribution filter and the detection filter coincide with each other. Therefore, the replacement time of the detection filter and the distribution filter can be made equal to each other.

The invention according to claim 5 is the processing liquid supply apparatus according to any one of claims 1 to 4, wherein a material of the detection filter is the same as a material of the flow filter.
According to this configuration, since the material of the detection filter is the same as the material of the distribution filter, the adsorption performance of the detection filter and the distribution filter, that is, the efficiency of capturing particles is almost the same. Therefore, the progress of deterioration of the detection filter and the distribution filter are equal to each other. Therefore, the deterioration of the flow filter can be determined with higher accuracy based on the detection result of the change in the pressure loss of the detection filter. Therefore, the replacement time of the detection filter and the distribution filter can be made equal to each other.

  The invention according to claim 6 further includes storage means (65) for storing correspondence data (70, PE) representing a correspondence relationship between a change in pressure loss of the detection filter and deterioration of the circulation filter, 6. The processing liquid supply apparatus according to claim 1, wherein the deterioration determination unit determines the deterioration of the flow filter based on the correspondence data and the detection result of the pressure loss change detection unit. .

According to this configuration, the correspondence data representing the correspondence between the change in the pressure loss of the detection filter and the deterioration of the circulation filter is stored in the storage unit. By comparing the detection result of the pressure loss detection means with the corresponding data as needed, it is possible to reliably determine the deterioration of the distribution filter.
According to a seventh aspect of the present invention, the processing liquid supply unit includes a plurality of processing liquid supply units (10A, 11A) capable of supplying a plurality of different types of processing liquids, and the storage unit includes the plurality of processing liquids. Correspondence data (70A, PE) representing a correspondence relationship between a change in pressure loss of the detection filter and deterioration of the filter is stored for each liquid supply unit. It is a processing-liquid supply apparatus of description.

Different types of processing liquids refer to a plurality of processing liquids having different liquid types, a plurality of processing liquids having the same liquid type but having different concentrations, and a plurality of processing liquids including both.
According to this configuration, the storage unit stores the correspondence data representing the correspondence relationship for each processing liquid supply unit. By using the correspondence data of the treatment liquid to be used, it is possible to reliably determine the deterioration of the filter.

In the invention according to claim 8, the upstream end (16A, 30A) of the first pipe is connected to the processing liquid supply unit, and the second pipe branches from the first pipe. It is a processing liquid supply apparatus as described in any one of Claims 1-7.
According to this configuration, since the second pipe is branched from the first pipe, the processing liquid from the processing liquid supply unit is simultaneously supplied to the first and second pipes. Therefore, the processing liquid from the common processing liquid supply unit can be simultaneously flowed to the distribution filter and the detection filter.

According to a ninth aspect of the present invention, the processing liquid supply unit includes a tank (10, 10A) in which a processing liquid is stored, and the first pipe is a processing liquid stored in the tank. The second pipe may include a branch pipe (17) branched from the circulation pipe and returning to the tank.
The invention according to claim 10 is any one of claims 1 to 7, wherein an upstream end (85A) and a downstream end (85B) of the second pipe are respectively connected to the processing liquid supply unit. The processing liquid supply device described in 1. above.

According to this configuration, the upstream end and the downstream end of the second pipe are not connected to the first pipe, but are connected to the processing liquid supply unit. Therefore, the flow rate of the processing liquid flowing through the first pipe is not easily affected by the flow rate of the processing liquid flowing through the second pipe, and the flow rate of the processing liquid in the first pipe is easily managed.
The invention according to claim 11 is characterized in that the pressure loss change detecting means includes flow rate detecting means (25, 26) for detecting the flow rate of the processing liquid on the downstream side of the detection filter of the second pipe. The processing liquid supply apparatus according to any one of Items 1 to 10.

  According to this configuration, the flow rate detecting means detects the flow rate of the processing liquid on the downstream side of the detection filter of the second pipe. Here, the detection filter gradually becomes clogged as it is used. This makes it difficult for the processing liquid to flow through the detection filter, so that the pressure loss of the detection filter gradually increases and at the same time the flow rate of the processing liquid decreases. Therefore, by keeping the flow rate of the processing liquid flowing into the second pipe constant, a change in the pressure loss of the detection filter can be detected from the difference between the upstream and downstream flow rates of the detection filter.

According to a twelfth aspect of the present invention, the pressure loss change detecting means detects the pressure difference in the second pipe on the upstream side and the downstream side of the detection filter of the second pipe. The detection means (81, 82) may be included.
The invention according to claim 13 is a flow filter (19, 20) for filtering the processing liquid supplied from the processing liquid supply section (10, 10A, 11, 11A) and flowing through the first pipe (15, 16). A method for detecting deterioration, wherein the processing liquid supplied from the processing liquid supply unit and flowing through a second pipe (17, 18, 85) which is a pipe different from the first pipe is filtered. A pressure loss change detecting step (S1) for detecting a change in pressure loss of the detection filter (21, 22), and a deterioration for determining deterioration of the filter based on the detected change in pressure loss of the detection filter. A filter deterioration detection method including a determination step (S2).

According to this method, in the deterioration determination step, based on the change in the pressure loss of the detection filter that filters the treatment liquid flowing through the second pipe that is different from the first pipe, Degradation can be accurately determined.
Further, since it is not necessary to provide an expensive device for accurately detecting the deterioration of the filter, an increase in cost can be suppressed. Therefore, it is possible to accurately detect the deterioration of the filter while suppressing an increase in cost.

It is the figure which showed typically the structure of the substrate processing system in which the processing liquid supply apparatus which concerns on one Embodiment of this invention was integrated. It is the figure which expanded the part shown by II in FIG. It is the figure which showed the principle which the filter for 1st distribution filters a process liquid. It is the figure which showed the principle which the filter for 1st distribution filters a process liquid. It is the figure which expanded the part shown by IV in FIG. It is a block diagram which shows the electrical structure of the said process liquid supply apparatus. It is the graph showing the correspondence of the change of the pressure loss of a filter for detection, and deterioration of the filter for distribution. It is a flowchart for demonstrating the filter degradation detection method. It is the figure which showed the 1st modification of one Embodiment of this invention. It is the figure which showed the 2nd modification of one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a diagram schematically showing a configuration of a substrate processing system 1 in which a processing liquid supply apparatus 3 according to an embodiment of the present invention is incorporated.
The substrate processing system 1 uses a processing liquid to process a semiconductor wafer W (hereinafter simply referred to as “wafer W”) as an example of a substrate, and to supply the processing liquid to the substrate processing section 2. The processing liquid supply device 3 is provided. As the treatment liquid, a rinse liquid and a chemical liquid are used. An example of the rinsing liquid includes deionized water (DIW) and the like, and examples of the chemical liquid include sulfuric acid and hydrofluoric acid. In the present embodiment, the processing liquid supply device 3 supplies only the chemical liquid to the substrate processing unit 2.

  The substrate processing unit 2 and the processing liquid supply device 3 may be a part of a common device, or may be devices independent of each other, that is, devices that can be moved independently of each other. That is, the substrate processing system 1 may include a substrate processing apparatus including the substrate processing unit 2 and the processing liquid supply device 3, or at a position away from the substrate processing apparatus including the substrate processing unit 2 and the substrate processing apparatus. You may provide the processing liquid supply apparatus 3 arrange | positioned.

The processing liquid supply apparatus 3 may be a single-wafer type apparatus that processes wafers W one by one, or may be a batch-type apparatus that collectively processes a plurality of wafers W. In the present embodiment, an example in which the substrate processing unit 2 is a single wafer type apparatus is shown.
The substrate processing unit 2 includes a box-shaped chamber 4, a spin chuck 5 that horizontally holds and rotates the wafer W in the chamber 4, a chemical nozzle 6 that supplies chemical liquid to the wafer W, and a rinse liquid to the wafer W. A rinsing liquid nozzle 7 to be supplied.

  As the spin chuck 5, a clamping chuck that holds the wafer W horizontally while holding the wafer W in the horizontal direction is employed. The spin chuck 5 includes a spin base 8 that holds the wafer W substantially horizontally and can rotate about the vertical axis, a rotation drive mechanism 9 that rotates the spin base 8 about the vertical axis, and a peripheral portion on the upper surface of the spin base 8. And a sandwiching member (not shown) arranged. The spin chuck 5 is not limited to the sandwich type, and for example, by vacuum-sucking the back surface of the wafer W, the wafer W is held in a horizontal posture, and further rotated around a vertical rotation axis in that state. A vacuum suction type (vacuum chuck) that rotates the wafer W held on the spin chuck 5 may be adopted.

Each of the chemical liquid nozzle 6 and the rinsing liquid nozzle 7 may be a fixed nozzle in which the landing positions of the chemical liquid and the rinsing liquid on the wafer W are fixed. A form of scan nozzle that moves along an arc trajectory passing through the center of rotation may be employed.
The processing liquid supply device 3 includes a chemical liquid tank (tank) 10 as a processing liquid supply unit. A chemical solution is stored in the chemical solution tank 10. A chemical liquid supply source 11 as a processing liquid supply unit is provided outside the processing liquid supply apparatus 3. The chemical solution supply source 11 has a tank (not shown), and a new chemical solution to be replenished to the chemical solution tank 10 is stored in the tank.

  A plurality of chemical liquid tanks 10 and chemical liquid supply sources 11 may be provided (see the broken line in FIG. 1). In this case, each of the plurality of chemical liquid supply sources 11A can supply different types of chemical liquids, and the chemical liquid supplied from the corresponding chemical liquid supply source 11A is stored in each chemical liquid tank 10A. Hereinafter, the case where one chemical solution supply source 11 and one chemical solution tank 10 are provided will be described as an example.

The processing liquid supply device 3 includes a supply unit 12 for supplying a chemical liquid to the substrate processing unit 2, a replenishment unit 13 for replenishing the chemical liquid tank 10 of the supply unit 12, and the supply unit 12 and the replenishment unit 13. And a control unit 27 (see FIG. 5 described later) for controlling opening and closing of the devices and valves provided.
The supply unit 12 includes a circulation pipe 15 as a first pipe, a first branch pipe 17 as a second pipe, a first flow filter (filter) 19, and a first detection filter (detection filter). 21 and a first flow meter 25 as a flow rate detecting means.

  The replenishment unit 13 includes a replenishment pipe 16 as a first pipe, a second branch pipe 18 as a second pipe, a second flow filter (filter) 20, and a second detection filter (detection filter). 22 and a second flow meter 26 as a flow rate detecting means. The processing liquid supply apparatus 3 of the present embodiment includes both the supply unit 12 and the replenishment unit 13, but may include only the supply unit 12.

Hereinafter, the direction in which the chemical solution circulates in the circulation pipe 15, the supplementary pipe 16, the first branch pipe 17, and the second branch pipe 18 is referred to as a chemical solution distribution direction. The upstream side in each chemical solution distribution direction is simply referred to as the upstream side, and the downstream side in each chemical solution distribution direction is simply referred to as the downstream side.
The circulation pipe 15 of the supply unit 12 is for circulating the chemical solution stored in the chemical solution tank 10. The circulation pipe 15 includes a supply pipe 30 for supplying the chemical liquid to the substrate processing unit 2 and a return pipe 31 for returning the chemical liquid flowing through the supply pipe 30 to the chemical liquid tank 10.

  An upstream end (upstream end) 30 </ b> A of the supply pipe 30 is connected to the chemical tank 10. The upstream end 30 </ b> A is also the upstream end of the circulation pipe 15. A downstream end (downstream end) of the supply pipe 30 is connected to the chemical nozzle 6. A chemical liquid supplied from the chemical liquid tank 10 circulates in the supply pipe 30. The supply pipe 30 includes a supply pipe pump 32, a supply flow rate adjustment valve 33, a supply valve 34, a supply pipe pressure gauge 35, a supply pipe flow meter 36, a first distribution filter 19 and a discharge valve 37. It is inserted in this order from.

  The supply pipe pump 32 is always driven when the processing liquid supply device 3 is activated, constantly pumps out the chemical liquid in the chemical liquid tank 10, and constantly feeds the chemical liquid into the supply pipe 30. The degree of opening of the supply flow rate adjustment valve 33 is adjusted in order to adjust the flow rate in the supply pipe 30. The supply valve 34 is opened and closed in order to supply the chemical solution into the supply pipe 30 and stop the supply of the chemical solution into the supply pipe 30. The supply pipe pressure gauge 35 is for detecting the pressure in the supply pipe 30. The supply pipe flow meter 36 is for detecting the flow rate of the chemical solution flowing through the supply pipe 30. The discharge valve 37 switches supply and stop of supply of the chemical liquid to the chemical liquid nozzle 6. The first distribution filter 19 is for filtering the chemical solution flowing through the supply pipe 30.

FIG. 2 is an enlarged view of a portion indicated by II in FIG.
The first circulation filter 19 has, for example, a cylindrical shape with one end closed. A plurality of holes 40 penetrating the first circulation filter 19 are formed in the entire thickness direction of the first circulation filter 19 over the entire area of the first circulation filter 19.
In the present embodiment, the hole 40 of the first circulation filter 19 has a square shape when viewed from the thickness direction of the first circulation filter 19 (see an enlarged view of a portion surrounded by a one-dot chain line in FIG. 2). Therefore, the hole diameter D1 of the hole 40 corresponds to the diameter (about 0.1 μm) of the circle 40A having an average value of the distance from the center of gravity of the square to the edge of the square. The hole 40 may have a polygonal shape other than a regular shape, a circular shape, or an elliptical shape as viewed from the thickness direction of the first circulation filter 19.

  The first distribution filter 19 has a filtration area R1. The flow rate Q1 of the chemical solution flowing through the first flow filter 19 corresponds to the product of the flow rate J1 of the chemical solution per unit filtration area of the first flow filter 19 and the filtration area R1. That is, the following formula (1) is established between the flow rate Q1, the flow rate J1, and the filtration area R1. The flow rate J1 is proportional to the number of holes 40 per unit filtration area, and is also proportional to the fourth power of the hole diameter D1.

Q1 = J1 × R1 (1)
The first circulation filter 19 is detachably attached to a first housing 41 that holds the first circulation filter 19 inside. The first housing 41 has an inflow portion 41A to which the downstream end of the supply pipe 30 upstream from the first distribution filter 19 is connected, and an upstream end of the supply pipe 30 downstream from the first distribution filter 19. And an outflow portion 41B connected thereto.

The interior of the first housing 41 includes an upstream space A1 of the first flow filter 19 through which the chemical liquid to be filtered flows through the first flow filter 19 and the first flow filter 19 through which the filtered chemical liquid flows. It is partitioned into a downstream space A2.
FIG. 3A and FIG. 3B are diagrams showing the principle by which the first circulation filter 19 filters the chemical solution. 3A and 3B, the upper side of the paper surface is the upstream space A1 of the first circulation filter 19 and the lower side of the paper surface is the downstream space A2 of the first circulation filter 19. FIG. 3B shows a state in which the deterioration of the first circulation filter 19 has progressed more than in FIG. 3A.

  Referring to FIG. 3A, the first distribution filter 19 is a standard closed type filter. When the chemical liquid is filtered by the first circulation filter 19, the chemical liquid flows from the upstream space A <b> 1 toward the downstream space A <b> 2 and passes through the hole 40 of the first circulation filter 19. The chemical solution present in the upstream space A1 includes particles 42. The particles 42 in the chemical liquid are adsorbed by the wall surface 19A of the first flow filter 19 that defines the holes 40 when passing through the holes 40, and are thereby captured in the holes 40, and the particles 42 are removed from the chemical liquid. .

  Referring to FIG. 3B, when the number of particles 42 captured by the first circulation filter 19 is gradually increased by continuing to use the first circulation filter 19, the first circulation filter 19 is gradually clogged. The adsorption performance of the first distribution filter 19 gradually decreases. Such a decrease in the adsorption performance of the first distribution filter 19 is referred to as deterioration of the first distribution filter 19. The portion through which the chemical solution can pass through the holes 40 of the first circulation filter 19 due to the deterioration of the first circulation filter 19 gradually becomes narrower as the number of particles 42 captured in the holes 40 increases. That is, since the chemical liquid becomes difficult to flow through the first distribution filter 19 as the first distribution filter 19 deteriorates, the pressure loss of the chemical liquid passing through the first distribution filter 19 (the chemical liquid flowing through the supply pipe 30 is the first The amount of energy lost when passing through the circulation filter 19. Hereinafter, simply referred to as “pressure loss of the first circulation filter 19” increases. Therefore, the flow rate Q1 of the chemical liquid flowing through the first circulation filter 19 is reduced.

If the hole diameter D1 of the first circulation filter 19 is small, the ratio of the particles 42 captured in the holes 40 to the holes 40 increases, and the first circulation filter 19 is likely to be clogged. That is, as the hole diameter D1 of the first circulation filter 19 decreases, the change in the pressure loss of the first circulation filter 19 increases.
Referring to FIG. 1, the return pipe 31 is branched from a portion between the first circulation filter 19 and the discharge valve 37 in the supply pipe 30. An upstream end (upstream end) of the return pipe 31 is connected to the supply pipe 30. The downstream end (downstream end) of the return pipe 31 is connected to the chemical tank 10. A chemical solution supplied from the chemical solution tank 10 circulates in the return pipe 31 via the supply pipe 30. A feedback valve 45 is interposed in the return pipe 31. The return valve 45 is opened and closed in order to supply the chemical solution into the return pipe 31 or stop the supply of the chemical solution into the return pipe 31.

  The first branch pipe 17 of the supply unit 12 branches from the supply pipe 30 of the circulation pipe 15 and returns to the chemical tank 10. An upstream end (upstream end) of the first branch pipe 17 is connected to a portion 30 </ b> B between the supply pipe pressure gauge 35 and the supply pipe flow meter 36 in the supply pipe 30. The downstream end (downstream end) of the first branch pipe 17 is connected to the chemical tank 10. A chemical solution supplied from the chemical solution tank 10 is circulated through the first branch pipe 17 via the circulation pipe 15.

  The pipe diameter of the first branch pipe 17 is smaller than the pipe diameter of the supply pipe 30. Therefore, the flow rate of the chemical solution flowing through the first branch pipe 17 is smaller than the flow rate of the chemical solution flowing through the supply pipe 30. The first branch pipe 17 is provided with a first detection filter 21 and a first flow meter 25 in order from the upstream side. The first detection filter 21 is for filtering the chemical solution flowing through the first branch pipe 17. The first flow meter 25 detects the flow rate of the chemical liquid flowing through the first branch pipe 17 on the downstream side of the first detection filter 21.

  With reference to FIG. 2, the first detection filter 21 has, for example, a cylindrical shape with one end closed. Since the pipe diameter of the first branch pipe 17 is smaller than the pipe diameter of the supply pipe 30, the chemical liquid flow rate q <b> 1 flowing through the first detection filter 21 is smaller than the flow quantity Q <b> 1 of the first distribution filter 19. Therefore, the first detection filter 21 is smaller than the first distribution filter 19. The filtration area r1 of the first detection filter 21 is smaller than the filtration area R1 of the first circulation filter 19. Therefore, the first detection filter 21 is less expensive than the first distribution filter 19.

  The material of the first detection filter 21 is the same as the material of the first distribution filter 19. The first detection filter 21 is a standard blocking type filter. Therefore, the first detection filter 21 captures the particles 42 in the chemical solution on the same principle as the first distribution filter 19 (see FIGS. 3A and 3B). The first detection filter 21 and the first distribution filter 19 have the same adsorption performance (see FIGS. 3A and 3B). Therefore, the progress of deterioration of the first detection filter 21 and the first circulation filter 19 are equal to each other. Similar to the first distribution filter 19, the chemical liquid continues to flow through the first detection filter 21, thereby making it difficult for the chemical liquid to flow through the first detection filter 21, and the pressure loss of the chemical liquid passing through the first detection filter 21. (The amount of energy lost when the chemical flowing through the first branch pipe 17 passes through the first detection filter 21. Hereinafter, simply referred to as “pressure loss of the first detection filter 21”) gradually increases. The flow rate q1 of the chemical solution is reduced. Further, as the hole diameter d1 of the first detection filter 21 is reduced, the first detection filter 21 is easily clogged, and the change in the pressure loss of the first detection filter 21 is increased.

  A plurality of holes 46 penetrating the first detection filter 21 in the thickness direction of the first detection filter 21 are formed in the entire area of the first detection filter 21. The hole 46 of the first detection filter 21 has a square shape when viewed from the thickness direction of the first detection filter 21 (see an enlarged view of a portion surrounded by a one-dot chain line in FIG. 2). The hole diameter d1 of the first detection filter 21 is smaller than the hole diameter D1 of the first flow filter 19. Specifically, the hole diameter d1 is about 0.01 to 0.05 μm. The hole 46 may have a polygonal shape other than a square shape, a circular shape, or an elliptical shape as viewed from the thickness direction of the first detection filter 21.

  In the first detection filter 21, as in the first distribution filter 19, the chemical flow rate j1 per unit filtration area of the first detection filter 21 is proportional to the number of holes 46 per unit filtration area, and the pore diameter It is also proportional to the fourth power of d1. Therefore, under the condition that the pressures in the first branch pipe 17 and the circulation pipe 15 are equal, the flow rate j1 is made equal to the flow rate J1 of the first circulation filter 19 by adjusting the number of holes 46 per unit filtration area. Is possible.

An expression similar to the expression (1) of the first circulation filter 19 is established between the flow rate q1, the flow rate j1, and the filtration area r1, and the flow rate q1 is proportional to the flow rate j1 and the filtration area r1.
The first detection filter 21 is detachably attached to a second housing 47 that holds the first detection filter 21 inside. The second housing 47 includes an inflow portion 47A to which the downstream end of the first branch pipe 17 on the upstream side of the first detection filter 21 is connected, and the first branch pipe 17 on the downstream side of the first detection filter 21. And an outflow portion 47B connected to the upstream end of the.

  Inside the second housing 47, the first detection filter 21 circulates the upstream space a <b> 1 of the first detection filter 21 in which the chemical liquid to be filtered flows, and the chemical liquid filtered by the first detection filter 21. The first detection filter 21 is partitioned into a downstream space a2. When the chemical liquid is filtered by the first detection filter 21, it flows from the upstream space a1 toward the downstream space a2 and passes through the hole 46 of the first detection filter 21.

  With reference to FIG. 1, it is assumed that the supply valve 34 and the discharge valve 37 are opened and the feedback valve 45 is closed while the supply piping pump 32 is driven. In this case, the chemical liquid pumped from the chemical tank 10 passes through the supply flow rate adjustment valve 33, the supply valve 34, the supply pipe pressure gauge 35, the supply pipe flow meter 36, the first distribution filter 19 and the discharge valve 37. Is supplied to the chemical nozzle 6. Further, a part of the chemical liquid pumped out from the chemical liquid tank 10 flows through the first branch pipe 17 and is returned to the chemical liquid tank 10. Specifically, the chemical that has flowed into the first branch pipe 17 from the portion 30 </ b> B between the supply pipe pressure gauge 35 and the supply pipe flowmeter 36 passes through the first detection filter 21 and the first flowmeter 25. And returned to the chemical tank 10. At this time, the ratio between the flow rate Q1 of the chemical flowing through the first circulation filter 19 and the flow rate q1 of the chemical flowing through the first detection filter 21 is always constant.

  In this state, when the discharge valve 37 is closed and the feedback valve 45 is opened, in this case, the chemical liquid pumped from the chemical tank 10 is supplied to the supply flow rate adjusting valve 33, the supply valve 34, and the supply piping pressure. The liquid is returned to the chemical tank 10 through the total 35, the supply pipe flow meter 36, the first flow filter 19 and the feedback valve 45. Even in this case, a part of the chemical liquid pumped out from the chemical liquid tank 10 flows through the first branch pipe 17 and is returned to the chemical liquid tank 10 in the same manner as before. Further, the ratio between the flow rate Q1 of the chemical liquid flowing through the first circulation filter 19 and the flow rate q1 of the chemical liquid flowing through the first detection filter 21 is always constant.

Since the first branch pipe 17 is branched from the circulation pipe 15, the chemical liquid from the chemical liquid tank 10 is simultaneously supplied to the first branch pipe 17 and the circulation pipe 15. Accordingly, the chemical solution from the common chemical solution tank 10 flows through the first distribution filter 19 and the first detection filter 21 simultaneously.
As the chemical solution continues to flow through the first branch pipe 17, the first detection filter 21 is gradually clogged, so that the flow rate q <b> 1 of the chemical solution flowing through the first detection filter 21 is reduced. Based on the pressure detected by the supply pipe pressure gauge 35, the degree of opening of the supply flow rate adjustment valve 33 is feedback adjusted so that the pressure of the supply pipe pressure gauge 35 becomes constant. Therefore, the pressure of the chemical solution flowing in the circulation pipe 15 and the first branch pipe 17 is kept constant. Therefore, the first flow meter 25 can detect the change in the pressure loss of the first detection filter 21 accompanying the deterioration of the first detection filter 21 by continuing to detect the change in the flow rate q1.

  The replenishment pipe 16 of the replenishment unit 13 is for replenishing the chemical liquid tank 10 with the chemical liquid from the chemical liquid supply source 11. An upstream end (upstream end) 16 </ b> A of the supplementary pipe 16 is connected to the chemical solution supply source 11. The downstream end (downstream end) of the replenishment pipe 16 is connected to the chemical tank 10. A chemical solution supplied from the chemical solution supply source 11 circulates in the replenishment pipe 16. A replenishment flow rate adjustment valve 50, a replenishment valve 51, a replenishment piping pressure gauge 52, and a second circulation filter 20 are interposed in the replenishment pipe 16 in order from the upstream side.

  The opening degree of the replenishment flow rate adjusting valve 50 is adjusted to adjust the flow rate in the refilling pipe 16. The replenishing valve 51 is opened and closed in order to supply the chemical liquid into the replenishing pipe 16 and stop the supply of the chemical liquid into the replenishing pipe 16. The supplementary pipe pressure gauge 52 detects the pressure in the supplementary pipe 16. The second distribution filter 20 is for filtering the chemical solution flowing through the refilling pipe 16.

FIG. 4 is an enlarged view of a portion indicated by IV in FIG.
The second distribution filter 20 is a filter having the same configuration as the first distribution filter 19. The material of the second distribution filter 20 is the same as the material of the first distribution filter 19. The second circulation filter 20 has a filtration area R2 equal to the filtration area R1 of the first circulation filter 19. The hole diameter D2 of the second circulation filter 20 is equal to the hole diameter D1 of the first circulation filter 19 (see also FIG. 2). Since the second circulation filter 20 is a standard block type filter, like the first circulation filter 19, the particles 42 in the chemical solution are captured on the same principle as the first circulation filter 19 (FIGS. 3A and 3B). reference).

Between the flow rate Q2 of the chemical solution flowing through the second circulation filter 20, the flow rate J2 of the chemical solution per unit filtration area of the second circulation filter 20, and the filtration area R2 of the second circulation filter 20 are the first circulation. The same formula as the formula (1) of the filter 19 is established. That is, the flow rate Q2 is proportional to the flow rate J2 and the filtration area R2.
The second circulation filter 20 is attached to a third housing 54 that holds the second circulation filter 20 inside. The second circulation filter 20 is detachable from the third housing 54. The third housing 54 has an inflow portion 54 </ b> A to which the downstream end of the refilling pipe 16 upstream of the second circulation filter 20 is connected, and an upstream end of the refilling pipe 16 downstream of the second circulation filter 20. And an outflow portion 54B connected thereto.

  Inside the third housing 54, the second flow filter 20 circulates the upstream space B1 of the second flow filter 20 through which the chemical solution to be filtered flows, and the chemical solution filtered by the second flow filter 20. It is partitioned into a downstream space B2 of the second circulation filter 20. When the chemical liquid is filtered by the second circulation filter 20, it flows from the upstream space B <b> 1 toward the downstream space B <b> 2 and passes through the hole 53 of the second circulation filter 20.

Referring to FIG. 1, the second branch pipe 18 branches from the supplementary pipe 16. An upstream end (upstream end) of the second branch pipe 18 is connected to a portion 16 </ b> B between the second circulation filter 20 and the supplementary pipe pressure gauge 52 in the supplementary pipe 16. The downstream end (downstream end) of the second branch pipe 18 is connected to the chemical tank 10.
The chemical solution supplied from the chemical solution supply source 11 is circulated through the second branch pipe 18 via the replenishment pipe 16. Since the pipe diameter of the second branch pipe 18 is smaller than the pipe diameter of the replenishment pipe 16, the flow rate of the chemical liquid flowing through the second branch pipe 18 is smaller than the flow volume of the chemical liquid flowing through the replenishment pipe 16. The pressure in the second branch pipe 18 is equal to the pressure in the supplementary pipe 16. The second branch pipe 18 includes a second detection filter 22 and a second flow meter 26 that detects the flow rate of the chemical liquid flowing through the second branch pipe 18 on the downstream side of the second detection filter 22. It is inserted in order from the side. The second detection filter 22 is for filtering the chemical solution flowing through the second branch pipe 18.

  Referring to FIG. 4, the second detection filter 22 has the same configuration as the first detection filter 21. That is, the material of the second detection filter 22 is the same as the material of the second distribution filter 20 that is the same material as the first distribution filter 19. The filtration area r2 of the second detection filter 22 is smaller than the filtration area R2 of the second distribution filter 20. Therefore, the second detection filter 22 is less expensive than the second distribution filter 20. Further, the hole diameter d2 of the second detection filter 22 is smaller than the hole diameter D2 of the second flow filter 20.

  Since the second detection filter 22 is a standard blockage type filter like the first distribution filter 19, the second detection filter 22 captures the particles 42 in the chemical solution based on the same principle as the first distribution filter 19 (FIGS. 3A and 3B). See also). The second detection filter 22 and the second distribution filter 20 have the same adsorption performance (see FIGS. 3A and 3B). Therefore, the deterioration levels of the second detection filter 22 and the second circulation filter 20 are equal to each other. Similarly to the first detection filter 21, the chemical liquid continues to flow through the second detection filter 22, thereby making it difficult for the chemical liquid to flow through the second detection filter 22, and the pressure loss of the chemical liquid passing through the second detection filter 22. At the same time as the amount of energy lost when the chemical flowing through the second branch pipe 18 passes through the second detection filter 22 (hereinafter simply referred to as “pressure loss of the second detection filter 22”) gradually increases. The flow rate q2 of the chemical solution is reduced. Further, as the hole diameter d2 of the second detection filter 22 is reduced, the second detection filter 22 is easily clogged, and the change in the pressure loss of the second detection filter 22 is increased.

Further, under the condition that the pressures in the second branch pipe 18 and the replenishment pipe 16 are equal, the number of holes 60 per unit filtration area of the second detection filter 22 is adjusted, whereby the second detection filter 22 It is possible to make the flow rate j2 of the chemical solution per unit filtration area equal to the flow rate J2 per unit filtration area of the second circulation filter 20.
An equation similar to the equation (1) of the first circulation filter 19 is established between the flow rate q2, the flow rate j2, and the filtration area r2 of the chemical liquid flowing through the second detection filter 22, and the flow rate q2 is equal to the flow rate j2. And proportional to the filtration area r2.

  The second detection filter 22 is attached to a fourth housing 61 that holds the second detection filter 22 inside. The second detection filter 22 is detachable from the fourth housing 61. The fourth housing 61 has an inflow portion 61A to which the downstream end of the supply pipe 30 upstream from the second detection filter 22 is connected, and an upstream end of the supply pipe 30 downstream from the second detection filter 22. And a connected outflow portion 61B.

  Inside the fourth housing 61, the second detection filter 22 circulates the upstream space b1 of the second detection filter 22 in which the chemical liquid to be filtered flows, and the chemical liquid filtered by the second detection filter 22. It is partitioned into a downstream space b2 of the second detection filter 22. When the chemical solution is filtered by the second detection filter 22, it flows from the upstream space b 1 toward the downstream space b 2 and passes through the hole 60 of the second detection filter 22.

  With reference to FIG. 1, in a state where the refill valve 51 is opened, the chemical solution from the chemical solution supply source 11 is supplied from the refill flow rate adjusting valve 50, the refill valve 51, the refill piping pressure gauge 52, and the second distribution filter 20. The liquid chemical tank 10 is replenished. A part of the chemical solution from the chemical solution supply source 11 flows through the second branch pipe 18 and is replenished to the chemical solution tank 10. Specifically, the chemical solution that has flowed into the second branch pipe 18 from the portion 16B between the replenishment pipe pressure gauge 52 and the second flow filter 20 passes through the second detection filter 22 and the second flow meter 26. Then, the chemical tank 10 is replenished. The ratio between the flow rate Q2 of the second flow filter 20 and the flow rate q2 of the second detection filter 22 is always constant.

Since the second branch pipe 18 is branched from the replenishment pipe 16, the chemical liquid from the chemical liquid supply source 11 is simultaneously supplied to the second branch pipe 18 and the replenishment pipe 16. Therefore, the chemical solution from the common chemical solution supply source 11 flows through the second distribution filter 20 and the second detection filter 22 simultaneously.
As the chemical solution continues to flow through the second branch pipe 18, the second detection filter 22 gradually becomes clogged, so that the flow rate q <b> 2 of the chemical solution flowing through the second detection filter 22 decreases. Based on the pressure detected by the replenishment piping pressure gauge 52, the degree of opening of the replenishment flow rate adjustment valve 50 is feedback adjusted so that the pressure of the chemical solution in the replenishment piping 16 and the second branch piping 18 becomes constant.

For this reason, the pressure of the chemical flowing through the refilling pipe 16 is kept constant. Therefore, the second flow meter 26 can detect the change in the pressure loss of the second detection filter 22 by continuing to detect the change in the flow rate q2 of the chemical liquid flowing through the second detection filter 22.
FIG. 5 is a block diagram showing an electrical configuration of the processing liquid supply apparatus 3. FIG. 6 is a graph showing the correspondence between the change in pressure loss of the first detection filter 21 and the deterioration of the first circulation filter 19.

Referring to FIG. 5, control unit 27 includes a microcomputer 64 and a monitor (not shown) that can display information.
The microcomputer 64 includes a CPU 66 and a memory 65 as storage means. The control unit 27 includes a pressure gauge for supply piping 35, a pressure gauge for supplementary piping 52, a flow meter for supply piping 36, a first flow meter 25, a second flow meter 26, a supply flow rate adjusting valve 33, and a supplementary flow rate adjusting valve 50. The supply pipe pump 32, the supply valve 34, the discharge valve 37, the feedback valve 45, and the replenishment valve 51 are connected as control targets.

The detected pressures of the supply piping pressure gauge 35 and the supplementary piping pressure gauge 52 are input to the control unit 27. Further, the detected flow rates of the supply pipe flow meter 36, the first flow meter 25, and the second flow meter 26 are input to the control unit 27.
The CPU 66 calculates the pressure loss of the first detection filter 21 based on the flow rate detected from the first flow meter 25 or the second flow meter 26 by executing the program. That is, the first flow meter 25 and the CPU 66 function as pressure loss change detection means for detecting a change in pressure loss of the first detection filter 21 in the first branch pipe 17. The second flow meter 26 and the CPU 66 function as pressure loss changing means for detecting a change in pressure loss of the second detection filter 22 in the second branch pipe 18.

The control unit 27 controls driving of the supply piping pump 32 and opening / closing operations of the supply valve 34, the discharge valve 37, the feedback valve 45, and the refill valve 51.
The memory 65 stores in advance correspondence data 70 representing the correspondence between the change in pressure loss of the first detection filter 21 and the degree of deterioration of the first circulation filter 19. In the present embodiment, as described above, the second detection filter 22 has the same configuration as the first detection filter 21, and the second distribution filter 20 has the same configuration as the first distribution filter 19. Therefore, the correspondence data 70 is also correspondence data representing a correspondence relationship between the change in the pressure loss of the second detection filter 22 and the degree of deterioration of the second circulation filter 20.

Unlike the present embodiment, when a plurality of the chemical liquid tanks 10 and the chemical liquid supply sources 11 are provided, as shown by the broken lines, the memory 65 stores in the chemical liquid tank 10A or each chemical liquid supply source 11A, that is, each chemical liquid tank 10A or Correspondence data 70A for each type of chemical stored in the tank of chemical supply 11A is stored (see also FIG. 1).
Referring to FIG. 6, the correspondence data 70 includes the usage period T of the first circulation filter 19 and the first detection filter 21 as the horizontal axis, the pressure loss variation P of the first detection filter 21 and the first It is a so-called biaxial graph with the deterioration degree F of the circulation filter 19 as the vertical axis.

The degradation degree F of the first circulation filter 19 gradually increases as the use period T of the first circulation filter 19 increases. When the degree of deterioration F reaches a predetermined threshold value FE, a defect in the manufacturing process of the wafer W (see FIG. 1), that is, a process defect occurs. A symbol “TE” is attached to the usage period of the first distribution filter 19 when a process failure occurs.
The amount P of change in pressure loss of the first detection filter 21 hardly increases until the use period T of the first detection filter 21 reaches the predetermined period T1. When the use period T exceeds the period T1, the change P in the pressure loss of the first detection filter 21 starts to increase. The period T1 is set shorter than the period TE.

When the usage period T of the first circulation filter 19 reaches the period T2 longer than the period T1 and shorter than the period TE, the replacement time of the first circulation filter 19 is set. A change amount P of the pressure loss of the first detection filter 21 when the period T2 is reached is defined as a threshold value PE.
In the present embodiment, the entire biaxial graph of FIG. 6 is the correspondence data 70, but only the threshold PE may be stored in the memory 65 as the correspondence data 70. When a plurality of chemical liquid tanks 10A and chemical liquid supply sources 11A are provided, the threshold value PE for each type of chemical liquid may be stored in the memory 65 as corresponding data 70A.

The CPU 66 executes the program, and based on such correspondence data 70 and the detection results of the first flow meter 25 and the second flow meter 26, the deterioration of the first distribution filter 19 and the second distribution filter The deterioration of the filter 20 is determined (see FIG. 5). That is, the CPU 66 functions as a deterioration determination unit.
Next, a filter deterioration detection method in which the CPU 66 detects the deterioration of the first distribution filter 19 and the deterioration of the second distribution filter 20 will be described.

FIG. 7 is a flowchart for explaining the filter deterioration detection method. Since the deterioration of the first distribution filter 19 and the deterioration of the second distribution filter 20 are detected by the same filter deterioration detection method, only the deterioration detection method of the first distribution filter 19 will be described below. The method for detecting the deterioration of the second distribution filter 20 is omitted.
Referring to FIG. 7, while the processing liquid supply device 3 is activated, the first flow meter 25 detects the flow rate on the downstream side of the first detection filter 21. Then, the CPU 66 executes a program to calculate (detect) a change in pressure loss of the first detection filter 21 from the flow rate detected by the first flow meter 25 (S1: pressure loss change detection step). The CPU 66 determines whether or not the first distribution filter 19 is based on whether or not the pressure loss change amount P of the first detection filter 21 has reached the threshold value PE, that is, based on the pressure loss change of the first detection filter 21. Degradation is determined (S2: Degradation determination step).

  When it is determined that the pressure loss change amount P of the first detection filter 21 has reached the threshold value PE (Yes in step S2), the control unit 27 indicates that the first distribution filter 19 has deteriorated (see FIG. 5). A warning is displayed on the monitor. Information that the first distribution filter 19 has deteriorated may be recorded as a log in the memory 65 (see FIG. 5). In this case, the warning that the first distribution filter 19 is deteriorated may not be displayed on the monitor of the control unit 27.

When the CPU 66 determines in step S2 that the pressure loss change amount P of the first detection filter 21 has not reached the threshold value PE (No in step S2), the process of FIG. 7 is returned.
By the above filter deterioration detection method, the deterioration of the first circulation filter 19 and the deterioration of the second circulation filter 20 are detected.

  As described above, according to this embodiment, the chemical liquid supplied from the common chemical liquid tank 10 is simultaneously supplied to the circulation pipe 15 and the first branch pipe 17. The first distribution filter 19 filters the chemical liquid flowing through the circulation pipe 15, and the first detection filter 21 filters the chemical liquid flowing through the first branch pipe 17. The chemical solution from the common chemical solution tank 10 flows through the first circulation filter 19 and the first detection filter 21 simultaneously. Therefore, the deterioration levels of the first distribution filter 19 and the first detection filter 21 are related to each other. Therefore, it is possible to accurately determine the deterioration of the first circulation filter 19 based on the detection result of the change in the pressure loss of the first detection filter 21. Therefore, since the first distribution filter 19 can be replaced at an appropriate time, the chemical solution supplied to the substrate processing unit 2 can be kept clean.

  Further, the chemical solution supplied from the common chemical solution supply source 11 is simultaneously supplied to the replenishment pipe 16 and the second branch pipe 18. The second circulation filter 20 filters the chemical liquid flowing through the replenishment pipe 16, and the second detection filter 22 filters the chemical liquid flowing through the second branch pipe 18. The chemical solution from the common chemical solution supply source 11 flows through the second circulation filter 20 and the second detection filter 22 simultaneously. Therefore, the degrees of deterioration of the second circulation filter 20 and the second detection filter 22 are related to each other. Therefore, it is possible to accurately determine the deterioration of the second circulation filter 20 based on the detection result of the change in the pressure loss of the second detection filter 22. Therefore, since the second distribution filter 20 can be replaced at an appropriate time, the chemical solution supplied to the substrate processing unit 2 can be kept clean.

Further, since it is not necessary to provide an expensive device such as a particle counter in order to accurately detect the deterioration of the first circulation filter 19 and the second circulation filter 20, it is possible to suppress an increase in cost.
Thereby, a clean chemical | medical solution can be supplied, suppressing the increase in cost.
Further, as described above, the hole diameters d1 and d2 of the first detection filter 21 and the second detection filter 22 are smaller than the hole diameters D1 and D2 of the first distribution filter 19 and the second distribution filter 20. As the hole diameters d1 and d2 become smaller, the first detection filter 21 and the second detection filter 22 are likely to be clogged, and the pressure loss of the first detection filter 21 and the second detection filter 22 changes. growing. Therefore, it is possible to accurately detect the deterioration of the first circulation filter 19 and the second circulation filter 20 from the change in pressure loss of the first detection filter 21 and the second detection filter 22.

  In addition, since the deterioration of the first circulation filter 19 can be accurately detected by using the first detection filter 21, it is not necessary to periodically replace the first circulation filter 19, and the first circulation filter 19. It can be performed according to the degree of degradation of the. Therefore, it is possible to prevent the replacement of the first distribution filter 19 that has been used only for a period shorter than necessary than the use period TE in which a process failure occurs (see FIG. 6). Further, even when a chemical solution having a low cleanliness is suddenly supplied from the chemical solution supply source 11 and the first distribution filter 19 is rapidly deteriorated, the first distribution filter 19 is surely replaced before a process failure occurs. can do. For the same reason, it is possible to prevent the replacement of the second circulation filter 20 that has been used for a period shorter than necessary than the use period TE in which a process failure occurs. Further, even when a chemical solution having a low cleanness is suddenly supplied from the chemical solution supply source 11 and the deterioration of the second distribution filter 20 is accelerated, the second distribution filter 20 is surely replaced before a process failure occurs. can do.

  Correspondence data 70 representing the correspondence between the change in pressure loss of the first detection filter 21 and the deterioration of the first circulation filter 19 is stored in the memory 65 in advance. The correspondence data 70 is also data representing the correspondence between the change in the pressure loss of the second detection filter 22 and the deterioration of the second circulation filter 20. The CPU 66 can reliably determine the deterioration of the first distribution filter 19 and the second distribution filter 20 by comparing the detection results of the first flow meter 25 and the second flow meter 26 with the corresponding data 70 as needed. it can.

As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.
FIG. 8 is a diagram showing a first modification of one embodiment of the present invention. In FIG. 8, the same members as those described above are denoted by the same reference numerals, and the description thereof is omitted. This also applies to FIG.

  Referring to FIG. 8, the treatment liquid supply device 3 of the first modification further includes a flow rate adjustment valve 75, a first pressure gauge 81 and a second pressure gauge 82. The first branch pipe 17 of the treatment liquid supply apparatus 3 of the first modification includes a flow rate adjustment valve 75, a first pressure gauge 81, a first detection filter 21, a second pressure gauge 82, and a first flow meter 25. They are installed in order from the upstream side. The flow rate adjustment valve 75 is opened and closed to adjust the pressure in the first branch pipe 17.

  The first pressure gauge 81 detects the pressure in the first branch pipe 17 on the upstream side of the first detection filter 21, and the second pressure gauge 82 is the first branch pipe on the downstream side of the first detection filter 21. The pressure in 17 is detected. That is, the first pressure gauge 81 and the second pressure gauge 82 constitute pressure difference detection means for detecting the pressure difference in the first branch pipe 17 on the upstream side and the downstream side of the first detection filter 21.

As shown in a portion surrounded by a broken line in FIG. 5, the opening / closing operation of the flow rate adjusting valve 75 is controlled by the control unit 27. The pressure detected by the first pressure gauge 81 and the second pressure gauge 82 is input to the control unit 27.
Referring to FIG. 8, when the chemical liquid flows through circulation pipe 15 and first branch pipe 17, first distribution filter 19 and first detection filter 21 are gradually clogged. When the first detection filter 21 is clogged, the flow rate of the chemical solution that is about to flow into the first branch pipe 17 from the portion 30B of the supply pipe 30 of the circulation pipe 15 is reduced. The controller 27 can keep the flow rate q1 of the chemical flowing through the first detection filter 21 constant by adjusting the degree of opening of the flow rate adjustment valve 75 so that the flow rate detected by the first flow meter 25 is constant. it can. In this state, the pressure loss of the first detection filter 21 can be detected by the difference (pressure difference) between the pressure detected by the second pressure gauge 82 and the pressure detected by the first pressure gauge 81. Therefore, by continuing to detect the pressure loss of the first detection filter 21 by the first pressure gauge 81 and the second pressure gauge 82, the pressure of the first detection filter 21 accompanying the deterioration of the first detection filter 21. The change in loss can be calculated (detected). That is, the first pressure gauge 81 and the second pressure gauge 82 are pressure loss change detecting means for detecting a change in pressure loss of the first detection filter 21.

In the first modification, the first distribution filter 19 is deteriorated based on the detection results of the first pressure gauge 81 and the second pressure gauge 82 by the same method as in this embodiment (see FIGS. 6 and 7). Determined. The deterioration of the second circulation filter 20 is determined by the same method (see FIGS. 6 and 7) as in the present embodiment.
According to the 1st modification, there exists the same effect as the above-mentioned embodiment.

In the first modification, the flow rate adjusting valve 75, the first pressure gauge 81, and the second pressure gauge 82 are interposed only in the first branch pipe 17, but the second branch pipe 18 also corresponds to these. A member may be interposed.
Next, a second modification of the present embodiment will be described.
FIG. 9 is a diagram showing a second modification of one embodiment of the present invention.

Referring to FIG. 9, the treatment liquid supply device 3 of the second modification includes an independent pipe 85 as a second pipe instead of the first branch pipe 17.
An upstream end (upstream end) 85A and a downstream end (downstream end) 85B of the independent pipe 85 are each connected to the chemical tank 10. In the independent pipe 85, an independent pipe pump 86, a pressure adjusting valve 87, a first pressure gauge 81, a first detection filter 21, and a first flow meter 25 are interposed in this order from the upstream side.

As shown in a portion surrounded by a broken line in FIG. 5, the independent piping pump 86 and the pressure adjustment valve 87 are connected to the control unit 27. The driving of the independent piping pump 86 and the degree of opening of the pressure adjusting valve 87 are controlled by the control unit 27.
The independent piping pump 86 is driven simultaneously with the supply piping pump 32 and stopped simultaneously. Therefore, when the chemical liquid flows through the circulation pipe 15, the chemical liquid also flows through the independent pipe 85. That is, the chemical solution supplied from the chemical solution tank 10 is simultaneously supplied to the circulation pipe 15 and the independent pipe 85.

  By adjusting the degree of opening of the pressure adjustment valve 87 while the independent piping pump 86 is being driven, the pressure in the independent piping 85 on the upstream side of the first detection filter 21, that is, the first pressure gauge 81 is The detected pressure can be kept constant. Therefore, the first flow meter 25 can detect a change in the flow rate q1 of the chemical liquid flowing through the first detection filter 21. Therefore, by continuously detecting the change in the flow rate q1 with the first flow meter 25, the change in the pressure loss of the first detection filter 21 accompanying the deterioration of the first detection filter 21 can be detected.

As described above, the CPU 66 calculates the pressure loss of the first detection filter 21 based on the flow rate detected from the first flow meter 25 by executing the program. That is, the first flow meter 25 and the CPU 66 function as pressure loss change detection means for detecting a change in pressure loss of the first detection filter 21 in the independent pipe 85.
In the second modification, the deterioration of the first circulation filter 19 and the second circulation filter 20 is determined by the same method (see FIGS. 6 and 7) as in the present embodiment.

According to the 2nd modification, there exists the same effect as the above-mentioned embodiment. In addition to these effects, the following effects are also achieved.
That is, the upstream end 85 </ b> A and the downstream end 85 </ b> B of the independent pipe 85 are not connected to the circulation pipe 15, but are connected to the chemical tank 10. Therefore, the flow rate of the chemical solution flowing through the circulation pipe 15 is not easily affected by the flow rate of the chemical solution flowing through the independent pipe 85, so that the flow rate of the chemical solution in the circulation pipe 15 is easily managed.

Further, the processing liquid supply device 3 of the second modification example includes the independent pipe 85 instead of the first branch pipe 17, but includes a pipe corresponding to the independent pipe 85 instead of the second branch pipe 18. Also good.
In addition, for example, when the first distribution filter 19, the second distribution filter 20, the first detection filter 21 and the second detection filter 22 are filters other than the standard blockage type, or are made of different materials. It is also possible. Even in this case, it is only necessary that the CPU 66 can detect the deterioration of the first flow filter 19 and the second flow filter 20 based on the detection results of the first flow meter 25 and the second flow meter 26.

  In the above-described embodiment, the wafer W is taken up as a substrate to be processed. However, the wafer W is not limited to the wafer W. For example, a glass substrate for a liquid crystal display device, a plasma display substrate, an FED substrate, an optical disk substrate, a magnetic substrate Other types of substrates such as a disk substrate, a magneto-optical disk substrate, a photomask substrate, a ceramic substrate, and a solar cell substrate may be processed.

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

2 Substrate processing section 3 Processing liquid supply device 10 Chemical liquid tank (processing liquid supply section, tank)
10A Chemical tank (treatment liquid supply unit, tank)
11 Chemical solution supply source (Processing solution supply unit)
11A Chemical solution supply source (processing solution supply unit)
15 Circulation piping (first piping)
16 Supplementary piping (first piping)
16A Upstream end 17 First branch pipe (second pipe, branch pipe)
18 Second branch pipe (second pipe)
19 First distribution filter (distribution filter)
20 Second distribution filter (distribution filter)
21 First detection filter (detection filter)
22 Second detection filter (detection filter)
25 1st flow meter (flow rate detection means, pressure loss change detection means)
26 Second flow meter (flow rate detection means, pressure loss change detection means)
30A upstream end 65 memory (storage means)
66 CPU (degradation determination means, pressure loss change detection means)
70 Corresponding data 70A Corresponding data 81 First pressure gauge (pressure difference detecting means, pressure loss change detecting means)
82 Second pressure gauge (pressure difference detection means, pressure loss change detection means)
85 Independent piping (second piping)
85A upstream end 85B downstream end d1 hole diameter d2 hole diameter D1 hole diameter D2 hole diameter j1 flow j2 flow J1 flow J2 flow PE threshold (corresponding data)
r1 Filtration area r2 Filtration area R1 Filtration area R2 Filtration area S1 Pressure loss change detection step S2 Degradation judgment step

Claims (13)

A processing liquid supply apparatus for supplying a processing liquid to a substrate processing unit,
A first pipe through which the processing liquid supplied from the processing liquid supply unit flows;
A flow filter for filtering the treatment liquid flowing through the first pipe;
A second pipe that is different from the first pipe and through which the processing liquid supplied from the processing liquid supply unit flows;
A detection filter for filtering the treatment liquid flowing through the second pipe,
The first and second pipes are supplied with the processing liquid supplied from the processing liquid supply unit at the same time,
The processing liquid supply apparatus is
Pressure loss change detecting means for detecting a change in pressure loss of the detection filter in the second pipe;
A treatment liquid supply apparatus, further comprising: a deterioration determination unit that determines deterioration of the flow filter based on a detection result of the pressure loss change detection unit.   The processing liquid supply apparatus according to claim 1, wherein a hole diameter of the detection filter is smaller than a hole diameter of the flow filter.   The processing liquid supply apparatus according to claim 1, wherein a filtration area of the detection filter is smaller than a filtration area of the circulation filter.   The processing liquid supply apparatus according to any one of claims 1 to 3, wherein the flow filter and the detection filter are provided such that the flow rates of the processing liquid per unit filtration area are equal to each other. .   The processing liquid supply apparatus according to any one of claims 1 to 4, wherein a material of the detection filter is the same as a material of the distribution filter. Storage means for storing correspondence data representing a correspondence relationship between a change in pressure loss of the detection filter and deterioration of the circulation filter;
The processing liquid supply apparatus according to claim 1, wherein the deterioration determination unit determines deterioration of the flow filter based on the correspondence data and a detection result of the pressure loss change detection unit. The processing liquid supply unit includes a plurality of processing liquid supply units capable of supplying a plurality of different types of processing liquids,
The storage unit stores correspondence data representing a correspondence relationship between a change in pressure loss of the detection filter and deterioration of the filter for each of the plurality of processing liquid supply units. The processing liquid supply apparatus as described in any one of Claims. The upstream end of the first pipe is connected to the processing liquid supply unit,
The processing liquid supply apparatus according to claim 1, wherein the second pipe is branched from the first pipe. The processing liquid supply unit includes a tank in which processing liquid is stored,
The first pipe includes a circulation pipe for circulating the processing liquid stored in the tank,
The processing liquid supply apparatus according to claim 8, wherein the second pipe includes a branch pipe that branches from the circulation pipe and returns to the tank.   The processing liquid supply apparatus according to claim 1, wherein an upstream end and a downstream end of the second pipe are respectively connected to the processing liquid supply unit.   The process according to any one of claims 1 to 10, wherein the pressure loss change detecting means includes a flow rate detecting means for detecting a flow rate of the processing liquid on the downstream side of the detection filter of the second pipe. Liquid supply device.   The pressure loss change detection means includes pressure difference detection means for detecting a pressure difference in the second pipe on the upstream side and the downstream side of the detection filter of the second pipe. The processing liquid supply apparatus as described in any one of Claims. A method for detecting deterioration of a flow filter for filtering a treatment liquid supplied from a treatment liquid supply unit and flowing through a first pipe,
Pressure loss change detection step of detecting a change in pressure loss of a detection filter for filtering the processing liquid supplied from the processing liquid supply unit and flowing through a second pipe that is a pipe different from the first pipe. When,
And a deterioration determination step of determining deterioration of the circulation filter based on the detected change in pressure loss of the detection filter.

Images