Substrate processing apparatus and substrate processing method

Abstract

To reduce a consumption amount of pure water in a cleaning treatment by recycling pure water.SOLUTION: A control part supplies an exhaust liquid used for a rear end SH of a cleaning treatment in a cleaning treatment part ONB1 to a cleaning treatment part ONB2, and supplies the exhaust liquid used for the rear end SH of the cleaning treatment in the cleaning treatment part ONB2 to a cleaning treatment part ONB1. The exhaust liquid used in the cleaning treatment part ONB1 is reused in the cleaning treatment part ONB2. The exhaust liquid used in the cleaning treatment part ONB2 is reused in the cleaning treatment part ONB1. Therefore, a supply amount of a pure water from the cleaning treatment part ONB1 and the cleaning treatment part ONB2 can be reduced. Thus, the consumption amount of the pure water in the cleaning treatment can be reduced by recycling them.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method for cleaning substrates such as semiconductor substrates, FPD (Flat Panel Display) substrates for liquid crystal displays and organic EL (Electroluminescence) display devices, glass substrates for photomasks, and substrates for optical disks. [Background technology]

[0002] Conventionally, this type of apparatus includes one equipped with a chemical tank for performing processing using a chemical solution and a pure water tank for performing processing using pure water (see, for example, Patent Document 1). In addition, in order to improve throughput, some apparatuses include multiple sets of chemical tanks and pure water tanks, for example, two sets such as a chemical tank (CHB1) and a pure water tank (ONB1), and a chemical tank (CHB2) and a pure water tank (ONB2) (see, for example, Patent Document 2).

[0003] Each pure water tank is supplied with pure water from a pure water supply source. Any pure water that overflows from the pure water tank after being supplied to the pure water tank is discarded. In other words, the pure water tank is always supplied with clean pure water from the pure water supply source. In other words, the cleaning process for substrates is always performed using only clean, new pure water.

[0004] The substrates processed in the pure water tank are, for example, substrates that have been processed with chemicals in a chemical tank. Therefore, when the substrates are immersed in the pure water in the pure water tank, a large amount of the chemicals adhering to the substrates is present in the pure water, resulting in a low resistivity. As the cleaning process progresses in the pure water tank, the chemicals in the pure water are discharged from the tank along with the pure water. As a result, the concentration of the chemicals decreases, causing the resistivity of the pure water in the pure water tank to increase. After a certain amount of time has passed, the resistivity of the pure water stops increasing, and the resistivity of the pure water in the pure water tank saturates at a value close to the theoretically maximum resistivity of pure water. This point generally marks the completion of the cleaning process.

[0005] This completion time can be determined in advance, for example, by supplying pure water at a predetermined flow rate, measuring the change in the resistivity of the pure water in the pure water tank from the time when a substrate that has undergone a predetermined chemical treatment is immersed, and measuring the time until the resistivity value reaches saturation. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 11-283947 (Fig. 3) [Patent Document 2] JP 2010-27771 A (Fig. 1) Summary of the Invention [Problem to be solved by the invention]

[0007] However, the conventional example having such a configuration has the following problems. In other words, in conventional apparatuses, clean pure water is supplied to each pure water tank and the pure water used in the cleaning process is discarded. This results in a problem of a very large amount of pure water being consumed in the cleaning process. This problem is particularly pronounced in substrate processing apparatuses that are equipped with multiple pure water tanks in order to improve throughput.

[0008] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can reduce the amount of pure water consumed in cleaning processing by recycling pure water. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention has the following configuration. That is, the invention described in claim 1 is a substrate processing apparatus for performing a cleaning process on a substrate, characterized in that it comprises: a first processing tank capable of accommodating a substrate; a second processing tank also capable of accommodating a substrate; a first pure water supply pipe connected to a pure water supply source and supplying pure water to the first processing tank; a first supply valve inserted in the first pure water supply pipe; a second pure water supply pipe connected to a pure water supply source and supplying pure water to the second processing tank; a second supply valve inserted in the second pure water supply pipe; a first recycle pipe that supplies a discharged liquid discharged from the first processing tank to the second processing tank; a first recycle valve inserted in the first recycle pipe; and a control unit that controls the opening and closing of the first supply valve, the second supply valve, and the first recycle valve.

[0010] [Operation and Effect] According to the invention described in claim 1, the control unit controls the opening and closing of the first supply valve, the second supply valve, and the first recycle valve, so that the wastewater supplied to the first treatment tank from the first pure water supply pipe and used in the cleaning process is supplied to the second treatment tank via the first recycle pipe. Since the wastewater used in the first treatment tank is reused in the second treatment tank, the amount of pure water supplied from the second pure water supply pipe to the second treatment tank can be reduced. Therefore, by recycling pure water, the amount of pure water consumed in the cleaning process can be reduced.

[0011] The discharged liquid referred to here is a liquid containing pure water. The discharged liquid contains pure water and a chemical liquid. The discharged liquid is less clean than pure water freshly supplied from a pure water supply source. The discharged liquid has a lower resistivity than pure water freshly supplied from a pure water supply source.

[0012] In addition, in the present invention, it is preferable that the system further includes a second recycle pipe that supplies the effluent discharged from the second treatment tank to the first treatment tank, and a second recycle valve inserted in the second recycle pipe, and that the control unit further controls the opening and closing of the second recycle valve (Claim 2).

[0013] The control unit supplies the waste liquid, which has been supplied to the second treatment tank and used in the cleaning treatment, to the first treatment tank through the second recycling pipe. Since the waste liquid used in the second treatment tank is reused for the first treatment tank, the amount of pure water supplied from the first pure water supply pipe to the first treatment tank can be reduced. Therefore, the amount of pure water consumed in the cleaning treatment can be further reduced.

[0014] Furthermore, in the present invention, it is preferable that the control unit manages the substrates to be cleaned by lot, and when a first lot is cleaned in the first processing tank and a second lot is cleaned in the second processing tank, at least a portion of the discharged liquid discharged from the first processing tank in the latter half of the cleaning processing of the first lot is supplied to the second processing tank through the first recycling pipe in the first half of the cleaning processing of the second lot (Claim 3).

[0015] When a first lot is cleaned in a first processing tank and a second lot is cleaned in a second processing tank, the resistivity of the discharged liquid in the first processing tank is high in the latter half of the cleaning process of the first lot. In other words, the cleanliness of the discharged liquid is higher in the latter half of the cleaning process of the first lot than in the first half of the cleaning process. In contrast, the resistivity of the discharged liquid is low in the first half of the cleaning process of the second lot because the discharged liquid contains a large amount of impurities adhering to the substrates. In other words, the first half of the cleaning process of the second lot is in a contaminated state with a lower cleanliness than the second half of the cleaning process. Therefore, the first recycling pipe supplies the discharged liquid from the first processing tank, which is cleaner than the first half of the cleaning process, to the second processing tank and is used in the first half of the cleaning process of the second lot. This allows the discharged liquid used in the cleaning process of the second lot to be reused without adversely affecting the cleaning process.

[0016] It should be noted that the first half of the cleaning process referred to here means that the cleanliness of the discharged liquid is lower than that of the second half of the cleaning process. The resistivity value is low in the first half of the cleaning process. In other words, the cleanliness of the discharged liquid is higher in the second half of the cleaning process than that of the first half of the cleaning process. The resistivity value is high in the second half of the cleaning process. Therefore, the first half and second half referred to here do not mean half the time until the cleaning process is completed. The first half and second half are determined according to the cleanliness of the discharged liquid, and are determined according to whether or not the cleanliness is such that the discharged liquid can be reused for the cleaning process.

[0017] Furthermore, in the present invention, it is preferable that the control unit manages the substrates to be cleaned by lot, and when a first lot is cleaned in the first processing tank and a second lot is cleaned in the second processing tank, at least a portion of the discharged liquid discharged from the first processing tank in the latter half of the cleaning processing of the first lot is supplied to the second processing tank through the first recycling pipe in the first half of the cleaning processing of the second lot, and at least a portion of the discharged liquid discharged from the second processing tank in the latter half of the cleaning processing of the second lot is supplied to the first processing tank through the second recycling pipe in the first half of the cleaning processing of a third lot that is processed in the first processing tank following the first lot (Claim 4).

[0018] When a first lot is cleaned in a first processing tank and a second lot is cleaned in a second processing tank, the resistivity of the pure water in the first processing tank is high in the latter half of the cleaning process of the first lot. In other words, the cleanliness of the discharged liquid is higher in the latter half of the cleaning process of the first lot than in the first half of the cleaning process. In contrast, the resistivity of the discharged liquid is low in the first half of the cleaning process of the second lot because the discharged liquid contains a large amount of impurities adhering to the substrates. In other words, the first half of the cleaning process of the second lot is in a contaminated state with a lower cleanliness than the second half of the cleaning process. Therefore, the first recycling pipe supplies the discharged liquid from the first processing tank, which is cleaner than the first half of the cleaning process, to the second processing tank and is used in the first half of the cleaning process of the second lot. Similarly, in the latter half of the cleaning process for the second lot, the effluent discharged from the second treatment tank is supplied to the first treatment tank through the second recycling pipe, and is used in the first half of the cleaning process for the third lot, which is processed immediately after the first lot. This allows the effluent used in the cleaning processes for the first and second lots to be reused without adversely affecting the cleaning process.

[0019] Furthermore, in the present invention, it is preferable that the first processing tank comprises a first inner tank capable of accommodating substrates, a first spray pipe provided at the bottom of the first inner tank for spraying pure water upward, and a first outer tank into which waste liquid overflowing from the upper edge of the first inner tank flows, the first pure water supply pipe being connected in communication with the first spray pipe and the second recycle pipe, and the second processing tank comprises a second inner tank capable of accommodating substrates, a second spray pipe provided at the bottom of the second inner tank for spraying pure water upward, and a second outer tank into which waste liquid overflowing from the upper edge of the second inner tank flows, and the second pure water supply pipe being connected in communication with the second spray pipe and the first recycle pipe (claim 5).

[0020] The first pure water supply pipe is connected in communication with the first jet pipe and the second recycle pipe. The second pure water supply pipe is connected in communication with the second jet pipe and the first recycle pipe. Therefore, the recycled effluent is supplied from the first jet pipe and the second jet pipe to the first treatment tank and the second treatment tank, so that the recycled effluent can be suitably supplied to the substrate.

[0021] In the present invention, the latter half of the cleaning treatment of the first lot is preferably the time from the start of the cleaning treatment until the resistivity exceeds 0.5 to 1 MΩ·cm (claim 6).

[0022] When the resistivity exceeds 0.5 to 1 MΩ·cm, the reuse of the discharged liquid does not adversely affect the cleaning process.

[0023] Furthermore, in the present invention, it is preferable that, in the latter half of the cleaning process of the second lot, the control unit does not supply the discharged liquid discharged from the first processing tank to the second processing tank, but supplies pure water from the second pure water supply pipe to the second processing tank (Claim 7).

[0024] In the latter half of the cleaning process in the second processing tank, the control unit does not supply the waste liquid discharged from the first processing tank to the second processing tank, but supplies pure water to the second processing tank from a second pure water supply pipe connected to the second processing tank. In other words, the control unit does not reuse the waste liquid through the first recycling pipe. Therefore, cleaning of the substrate can be completed in a clean state.

[0025] Furthermore, in the present invention, it is preferable that, in the first half of the cleaning process for the second lot, the control unit mixes at least a portion of the discharged liquid discharged from the first processing tank with pure water flowing through the second pure water supply pipe and supplies the resultant to the second processing tank, and, in the first half of the cleaning process for the third lot, mixes at least a portion of the discharged liquid discharged from the second processing tank with pure water flowing through the first pure water supply pipe and supplies the resultant to the first processing tank (Claim 8).

[0026] In the first half of the cleaning process for the second lot, at least a portion of the effluent discharged from the first processing tank is mixed with pure water flowing through the second pure water supply pipe and supplied to the second processing tank. In the first half of the cleaning process for the third lot, at least a portion of the effluent discharged from the second processing tank is mixed with pure water flowing through the first pure water supply pipe and supplied to the first processing tank. Therefore, the amount of pure water and effluent required for the cleaning process can be supplied.

[0027] In the present invention, it is preferable that the first recycle pipe is provided with a buffer tank (claim 9), and it is preferable that the second recycle pipe is provided with a buffer tank (claim 10).

[0028] The first recycling pipe (second recycling pipe) is equipped with a buffer tank. Therefore, it is possible to provide a margin in the timing of supplying the discharged liquid from the first recycling pipe (second recycling pipe) to the second treatment tank (first treatment tank). As a result, when the first and second lots are loaded into the first and second treatment tanks, even if the latter half of the cleaning process for the first lot and the former half of the cleaning process for the second lot are not synchronized, the discharged liquid can be suitably reused.

[0029] The invention described in claim 11 is a substrate processing method for performing a cleaning process on substrates, characterized in that when the substrates to be cleaned are managed by lot, at least a portion of the discharged liquid discharged from the first processing tank is supplied to the second processing tank when the following steps are performed in that order: starting the cleaning process for a first lot in a first processing tank capable of accommodating substrates; and, after the step of starting the cleaning process for the first lot, starting the cleaning process for a second lot in a second processing tank capable of accommodating substrates.

[0030] [Operation and Effect] According to the invention described in claim 11, the wastewater used in the first treatment tank is reused in the second treatment tank, so the amount of pure water supplied to the second treatment tank can be reduced. Therefore, by recycling the pure water, the amount of pure water consumed in the cleaning process can be reduced.

[0031] Furthermore, in the present invention, after the process of starting the cleaning process for the second lot, when the process of starting the cleaning process for a third lot to be processed in the first processing tank following the first lot is carried out in the first processing tank, it is preferable that at least a portion of the discharged liquid discharged from the second processing tank is supplied to the first processing tank (Claim 12).

[0032] Since the wastewater used in the second treatment tank is reused for the first treatment tank, the amount of pure water supplied to the first treatment tank can be reduced, thereby further reducing the amount of pure water consumed in the cleaning treatment. [Effects of the Invention]

[0033] In the substrate processing apparatus according to the present invention, the control unit controls the opening and closing of the first supply valve, the second supply valve, and the first recycle valve to supply the waste liquid, which has been supplied to the first processing tank from the first pure water supply pipe and used in the cleaning process, to the second processing tank via the first recycle pipe. Because the waste liquid used in the first processing tank is reused in the second processing tank, the amount of pure water supplied from the second pure water supply pipe to the second processing tank can be reduced. Therefore, by recycling the pure water, the amount of pure water consumed in the cleaning process can be reduced. [Brief explanation of the drawings]

[0034] [Figure 1] 1 is a plan view showing a schematic configuration of a substrate processing apparatus according to an embodiment; [Figure 2] 1 is a block diagram showing a schematic configuration of a substrate processing apparatus according to an embodiment. [Figure 3] FIG. 2 is a view showing a cleaning processing unit in the substrate processing apparatus. [Figure 4] 10 is a graph showing an example of a change in resistivity during a cleaning process. [Figure 5] 10 is a graph illustrating a process of overlapping the latter half of a cleaning process with the first half of another cleaning process. [Figure 6] 10 is a time chart showing an example of processing four lots. [Figure 7] FIG. 10 is a diagram showing a modified example of the cleaning processing unit. [Figure 8] FIG. 10 is a diagram showing another modified example of the cleaning processing unit. DETAILED DESCRIPTION OF THE INVENTION

[0035] An embodiment of the present invention will now be described with reference to the drawings.

[0036] Fig. 1 is a plan view showing a schematic configuration of a substrate processing apparatus according to an embodiment, and Fig. 2 is a block diagram showing a schematic configuration of a substrate processing apparatus according to an embodiment.

[0037] <1. Device configuration>

[0038] The substrate processing apparatus according to the embodiment is, for example, an apparatus for performing chemical processing, cleaning processing, and drying processing on substrates W. A plurality of substrates W (for example, 25 substrates) are stored in a cassette 1 in a stacked manner in a horizontal position. The cassette 1 storing unprocessed substrates W is placed in an input section 3. The input section 3 has two mounting tables 5 on which the cassettes 1 are placed.

[0039] On the opposite side of the center of the substrate processing apparatus from the input unit 3 is the discharge unit 7. The discharge unit 7 stores processed substrates W in cassettes 1 and discharges the cassettes 1. The discharge unit 7, which functions in this manner, is equipped with two mounting tables 9 for placing the cassettes 1, similar to the input unit 3.

[0040] A first transport mechanism CTC configured to be movable between the input unit 3 and the discharge unit 7 is provided at a position along these units. The first transport mechanism CTC removes all of the substrates W stored in the cassettes 1 placed in the input unit 3, and then transports them to the second transport mechanism WTR. After receiving the processed substrates W from the second transport mechanism WTR, the first transport mechanism CTC stores the substrates W in the cassette 1. The second transport mechanism WTR is configured to be movable along the longitudinal direction of the substrate processing apparatus.

[0041] On the side of the discharge unit 7 in the movement direction of the second transport mechanism WTR, a drying unit LPD is provided for storing a plurality of substrates W in a low-pressure chamber and drying them.

[0042] A first processing section 11 is disposed at a position adjacent to the drying processing section LPD in the movement direction of the second transport mechanism WTR.

[0043] The first processing unit 11 includes a cleaning unit ONB1 and a chemical processing unit CHB1. The cleaning unit ONB1 performs cleaning processing on substrates W using pure water. The chemical processing unit CHB1 performs chemical processing on substrates W using a processing liquid containing a chemical. The first processing unit 11 includes an auxiliary transport mechanism LFS1. The auxiliary transport mechanism LFS1 transfers substrates W to and from the second transport mechanism WTR. The auxiliary transport mechanism LFS1 is configured to be movable between the pure water processing unit ONB1 and the chemical processing unit CHB1. The auxiliary transport mechanism LFS1 can move up and down only between the pure water processing unit ONB1 and the chemical processing unit CHB1.

[0044] A second processing unit 13 is provided adjacent to the first processing unit 11. The second processing unit 13 has the same configuration as the first processing unit 11 described above.

[0045] That is, second processing unit 13 includes cleaning processing unit ONB2, chemical processing unit CHB2, and sub-transport mechanism LFS2. Cleaning processing unit ONB2 has the same configuration as cleaning processing unit ONB1 described above. Chemical processing unit CHB2 has the same configuration as chemical processing unit CHB1 described above. Sub-transport mechanism LFS2 has the same configuration as sub-transport mechanism LFS1 described above.

[0046] The control unit 15 comprehensively controls each unit such as the first transport mechanism CTC described above. The control unit 25 includes a CPU and a memory. The memory of the control unit 25 handles substrates W as lots and stores in advance recipes and the like that define how each lot is to be processed in the first processing unit 11 and the second processing unit 13. The recipes pre-describe, for example, the flow rate of pure water to be supplied to the inner bath 19 and the time for which the substrates W are to be immersed in the inner bath 19.

[0047] Now, reference is made to Fig. 3. Fig. 3 is a diagram showing a cleaning processing section in a substrate processing apparatus.

[0048] The cleaning processing unit ONB1 includes a processing tank 17. The processing tank 17 includes an inner tank 19 and an outer tank .

[0049] The inner tank 19 can accommodate the substrate W together with the sub-transport mechanism LFS1. The inner tank 19 is provided with jet pipes 23 on both sides of its bottom. The jet pipes 23 have a long axis extending in the front-to-rear direction of the paper surface in FIG. 3, and have a plurality of jet nozzles (not shown) formed along the long axis. An outer tank 21 is provided on the outer periphery of the upper edge of the inner tank 19. The outer tank 21 collects pure water that is supplied to the inner tank 19 from the jet pipes 23 and overflows from the upper edge of the inner tank 19.

[0050] One end of a supply pipe 25 is connected to the ejection pipe 23. The other end of the supply pipe 25 is connected to a pure water supply source 27. The pure water supply source 27 supplies pure water having a resistivity value that is approximately the theoretical value (16 MΩ cm). The supply pipe 25 is provided with a flow rate adjustment valve 29, an on-off valve 31, and a flow meter 33 from a position close to the pure water supply source 27 toward the ejection pipe 23.

[0051] The flow rate adjustment valve 29 adjusts the flow rate of the pure water flowing through the supply pipe 25. The on-off valve 31 switches between a state in which the flow of the pure water through the supply pipe 25 is permitted and a state in which the flow of the pure water is blocked. The flow meter 33 measures the flow rate of the pure water flowing through the supply pipe 25. The measured flow rate is output to the control unit 15.

[0052] A resistivity meter 35 is attached to one side of the inner tank 19. The resistivity meter 35 measures the resistivity value of the pure water stored in the inner tank 19. The measured resistivity value is output to the control unit 15.

[0053] The outer bath 21 is provided with a discharge pipe 37. Specifically, one end of the discharge pipe 37 is connected to the bottom surface of the outer bath 21. The discharge pipe 37 discharges the discharge liquid from the other end. The discharge liquid is pure water containing particles detached from the substrate W and part of the chemical liquid washed away from the substrate W. The discharge liquid may also be pure water containing almost no impurities. The discharge pipe 37 is provided with an on-off valve 39. The on-off valve 39 controls the discharge of the discharge liquid. In other words, the on-off valve 39 allows the flow of the discharge liquid or blocks the flow of the discharge liquid. A branch section 41 is provided in the discharge pipe 37 between the outer bath 21 and the on-off valve 39.

[0054] Cleaning unit ONB1 has the above-described structure. Cleaning unit ONB2 of second processing unit 13 has the same structure as cleaning unit ONB1 described above.

[0055] Cleaning unit ONB1 includes a recycle pipe 43. One end of recycle pipe 43 is connected in communication with branching unit 41. The other end of recycle pipe 43 is connected in communication with supply pipe 25 of cleaning unit ONB2.

[0056] Specifically, the other end of the recycle pipe 43 is connected in communication between the flow meter 33 of the cleaning processing unit ONB2 and the ejection pipe 23. The recycle pipe 43 is provided with an on-off valve 45, a pump 47, and a flow meter 49, in this order from the branching part 41 side.

[0057] The on-off valve 45 allows or blocks the flow of the effluent discharged into the discharge pipe 37 of the cleaning processing unit ONB1 and flowing into the recycle pipe 43. The pump 47 pressure-feeds the effluent discharged into the discharge pipe 37 of the cleaning processing unit ONB1 from the recycle pipe 43 to the supply pipe 25 of the cleaning processing unit ONB2. The flow meter 49 measures the flow rate of the effluent flowing through the recycle pipe 43. The flow rate measured by the flow meter 49 is output to the control unit 15. The recycle pipe 43 supplies the effluent used in the cleaning processing unit ONB1 and discharged into the outer tank 21 to the cleaning processing unit ONB2.

[0058] Cleaning processing unit ONB2 is equipped with a recycle pipe 53. One end of the recycle pipe 53 is connected in communication with branching unit 41 of cleaning processing unit ONB2. The other end of the recycle pipe 53 is connected in communication with supply pipe 25 of cleaning processing unit ONB1. Specifically, the other end of the recycle pipe 53 is connected in communication between flow meter 33 and ejection pipe 23 of cleaning processing unit ONB1. Recycle pipe 53 is equipped with, in this order from the branching unit 41 side, an on-off valve 55, a pump 57, and a flow meter 59.

[0059] The on-off valve 55 allows or blocks the flow of the effluent discharged into the discharge pipe 37 of the cleaning processing unit ONB2 and flowing into the recycle pipe 53. The pump 57 pressure-feeds the effluent discharged into the discharge pipe 37 of the cleaning processing unit ONB2 from the recycle pipe 53 to the supply pipe 25 of the cleaning processing unit ONB1. The flow meter 59 measures the flow rate of the effluent flowing through the recycle pipe 53. The flow rate measured by the flow meter 59 is output to the control unit 15. The recycle pipe 53 supplies the effluent used in the cleaning processing unit ONB2 and discharged into the outer tank 21 to the cleaning processing unit ONB1.

[0060] The processing tank 17 of cleaning processing unit ONB1 corresponds to the "first processing tank" in the present invention, and the processing tank 17 of cleaning processing unit ONB2 corresponds to the "second processing tank" in the present invention. The supply pipe 25 of cleaning processing unit ONB1 corresponds to the "first pure water supply pipe" in the present invention, and the supply pipe 25 of cleaning processing unit ONB2 corresponds to the "second pure water supply pipe" in the present invention. The flow rate adjustment valve 29 and the on-off valve 31 of cleaning processing unit ONB1 correspond to the "first supply valve" in the present invention, and the flow rate adjustment valve 29 and the on-off valve 31 of cleaning processing unit ONB2 correspond to the "second supply valve" in the present invention. The recycle pipe 43 corresponds to the "first recycle pipe" in the present invention, and the recycle pipe 53 corresponds to the "second recycle pipe" in the present invention. The on-off valve 45 corresponds to the "first recycle valve" in the present invention, and the on-off valve 55 corresponds to the "second recycle valve" in the present invention.

[0061] The inner tank 19 of the cleaning processing unit ONB1 corresponds to the "first inner tank" in the present invention, and the inner tank 19 of the cleaning processing unit ONB2 corresponds to the "second inner tank" in the present invention. The ejection pipe 23 of the cleaning processing unit ONB1 corresponds to the "first ejection pipe" in the present invention, and the ejection pipe 23 of the cleaning processing unit ONB2 corresponds to the "second ejection pipe" in the present invention. The outer tank 21 of the cleaning processing unit ONB1 corresponds to the "first outer tank" in the present invention, and the outer tank 21 of the cleaning processing unit ONB2 corresponds to the "second outer tank" in the present invention.

[0062] In a normal cleaning process that does not involve recycling, as will be described later, the control unit 15 operates each unit, for example, as follows.

[0063] The control unit 15 closes the on-off valves 45 and 55. The control unit 15 opens the on-off valve 39. In this state, the control unit 15 operates the flow rate adjustment valve 29 to set the flow rate of the pure water flowing through the supply pipe 25 to the target flow rate of the supply amount specified in the recipe. The control unit 15 opens the on-off valve 31. As a result, in the cleaning processing unit ONB1 (ONB2), pure water is supplied to the inner bath 19, and the cleaning processing is performed on the substrates W immersed in the inner bath 19.

[0064] At this time, it is preferable that the control unit 15 monitors the flow rate of the flow meter 33, and if there is a difference from the target value of the supply rate defined in the recipe, it operates the flow rate adjustment valve 29 to eliminate the difference. In other words, it is preferable that when supplying pure water, the control unit 15 performs feedback control so that the flow rate of the pure water supply matches the target value.

[0065] <2. Specific resistance value after cleaning treatment> Please refer to Figure 4. Figure 4 is a graph showing an example of the change in resistivity during cleaning treatment. In this graph, the vertical axis represents resistivity [Ω·cm] and the horizontal axis represents cleaning time [sec].

[0066] In the cleaning processing unit ONB1 (ONB2), pure water is supplied from a pure water supply source 27 to a supply pipe 25. The pure water supplied from the supply pipe 25 is supplied toward the bottom surface of the inner bath 19 through a pair of jet pipes 23. The pure water supplied toward the center of the bottom surface of the inner bath 19 joins together in the center of the inner bath 19 and rises, rising along the surface of the substrate W. The pure water stored in the inner bath 19 overflows over the upper edge of the inner bath 19 and into the outer bath 21. The pure water recovered in the outer bath 21 is discharged as a waste liquid through a discharge pipe 39.

[0067] 4 is a graph showing an example of changes in resistivity measured by the resistivity meter 35 when a substrate W that has been subjected to chemical processing in the chemical processing unit CHB1 (CHB2) is immersed in pure water in the cleaning processing unit ONB1 (ONB2) for cleaning. For example, the control unit 15 does not refer to the output of the resistivity meter 35 when cleaning the substrate W. For example, the control unit 15 controls the cleaning processing according to the time that reaches the point t2, which is determined in advance by experiment, according to the chemical processing performed on the substrate W.

[0068] The control unit 15 controls the elevation of the sub-transport mechanism LFS1 (LFS2). The control unit 15 operates the sub-transport mechanism LFS1 (LFS2) to move the substrate W between an upper position above the inner bath 19 and a processing position inside the inner bath 19. The control unit 15 positions the substrate W at the processing position by the sub-transport mechanism LFS1 (LFS2) and starts the cleaning process with pure water, and this is defined as time 0. For example, at time t1, the resistivity becomes approximately SR1, and at time t2, the resistivity is almost saturated and becomes SR2. Time t2 is the time when the cleaning process with pure water ends.

[0069] Here, the resistivity SR2 is the theoretical maximum value of the pure water supplied from the pure water supply source 27. The resistivity SR2 is, for example, 16 MΩ cm. More specifically, it is the maximum resistivity value of the pure water that can be produced by the pure water production apparatus that supplies the pure water to the pure water supply source 27.

[0070] The specific resistance SR1 is, for example, 1 MΩ·cm. Alternatively, the specific resistance SR1 is determined in the range of 0.5 to 1 MΩ·cm, taking into consideration the final cleaning finish. From time 0 until time t1, the cleaning process starts, and the impurity concentration in the pure water stored in the inner tank 19 is high. At time t1, as the cleaning process progresses and impurities are discharged from the inner tank 19, the impurity concentration in the pure water stored in the inner tank 19 begins to decrease rapidly, and the cleanliness level increases. At time t2, the cleaning process is completely completed, and the impurity concentration in the pure water stored in the inner tank 19 is almost zero, resulting in a clean state.

[0071] Here, the period from time 0 to time t1 in the cleaning time with pure water is defined as the first half FH, and the period from time t1 to time t2 is defined as the second half SH. The second half SH has a much higher specific resistance value than the first half FH. In other words, in the second half SH, the discharged liquid discharged from the inner tank 19 via the outer tank 21 has a higher degree of cleanliness than the discharged liquid in the first half FH.

[0072] Therefore, for example, if cleaning unit ONB1 starts cleaning earlier than cleaning unit ONB2, the effluent discharged from the outer tank 21 in the latter half SH of cleaning unit ONB1 has a higher specific resistance than the effluent discharged from the outer tank 21 in the first half FH of cleaning unit ONB2. In other words, the effluent discharged from the outer tank 21 in the latter half SH of cleaning unit ONB1 has a higher degree of cleanliness than the effluent discharged from the outer tank 21 in the first half FH of cleaning unit ONB2.

[0073] <3. Control Unit Operation> Reference is now made to Figure 5. Figure 5 is a graph illustrating a process of overlapping the latter half of a cleaning process with the first half of another cleaning process.

[0074] For example, assume that cleaning processing unit ONB1 starts cleaning with pure water first, and then cleaning processing unit ONB2 starts cleaning with pure water. In this case, control unit 15 performs processing so that the second half SH of the cleaning processing in cleaning processing unit ONB1 overlaps with the first half FH of the cleaning processing in cleaning processing unit ONB2. Alternatively, if the second half SH and the first half FH of the cleaning processing overlap even partially for cleaning processing unit ONB1, which started cleaning processing first, and cleaning processing unit ONB2, which started cleaning processing afterwards, control unit 15 operates each unit to reuse the discharged liquid from the second half SH of cleaning processing unit ONB1 for cleaning in the first half FH of cleaning processing unit ONB2.

[0075] Specifically, when the discharged liquid can be reused for cleaning, the control unit 15 supplies the pure water to the inner tank 19 from the supply pipe 25 in the first half FH of the cleaning processing unit ONB2 using only the discharged liquid in the recycle pipe 43.

[0076] The control unit 15 does not need to transport each lot so that the latter half SH in the cleaning unit ONB1 (ONB2) and the first half FH in the cleaning unit ONB2 (ONB1) completely overlap. In other words, the control unit 15 only needs to reuse the discharged liquid when the latter half SH in the cleaning unit ONB1 (ONB2) and the first half FH in the cleaning unit ONB2 (ONB1) at least partially overlap. This allows at least a portion of the discharged liquid from the latter half SH in the cleaning unit ONB1 (ONB2) to be reused.

[0077] When such recycling is performed, it is preferable that the control unit 15 performs the following control.

[0078] For example, the control unit 15 prevents the supply of waste liquid to the cleaning unit ONB2 (ONB1) via the recycle pipe 43 (53) from exceeding the flow rate of the pure water supplied from the supply pipe 25 of the cleaning unit ONB1 (ONB2) to the inner tank 19. In other words, the control unit 15 supplies the waste liquid to the cleaning unit ONB2 (ONB1) via the recycle pipe 43 (53) within the flow rate of the pure water supplied to the inner tank 19 of the cleaning unit ONB1 (ONB2). This prevents a shortage of the waste liquid to be recycled, which can cause an unstable supply state on the inner tank 19 side to which the waste liquid is supplied, and can thereby prevent adverse effects on the processing.

[0079] <4. Lot processing> Now, reference is made to Figure 6. Figure 6 is a time chart showing an example of processing four lots.

[0080] In the following description, in order to facilitate understanding of the invention, an example will be given in which a single or multiple substrates W are treated as one lot, and each lot is processed in a substrate processing apparatus.

[0081] In the following description, among the resources that are the objects of operation of the control unit 15, the transport system and the chemical processing unit CHB1 (CHB2) are not particularly limited. Therefore, for the sake of explanation, the chemical processing unit CHB1 (CHB2) will be referred to as the chemical processing unit CHB, and the second transport mechanism WTR and the sub-transport mechanism LFS1 (LFS2) will not be described. As an example, the case where four lots are processed consecutively will be described.

[0082] In FIG. 6, the first lot is represented by the symbol L1. Similarly, the second lot is represented by the symbol L2, the third lot by the symbol L3, and the fourth lot by the symbol L4. The first lot L1 to the fourth lot L4 are assumed to be loaded into the substrate processing apparatus in that order. In FIG. 6, as an example, each unit time of processing is represented by a square. In FIG. 6, the first half FH of the pure water cleaning process is represented by a hatched square, and the second half SH is represented by a regular square.

[0083] An example will be described below in which control unit 15 transfers first to fourth lots L1 to L4 after chemical processing by chemical processing unit CHB, and then performs cleaning processing in cleaning processing units ONB1 and ONB2.

[0084] At time t0, the control unit 15 processes the first lot L1 in the chemical processing unit CHB. The chemical processing by the chemical processing unit CHB is completed at time t1. The control unit 15 transports the first lot L1 from time t1 to time t2, and transports the first lot L1 to the cleaning processing unit ONB1. The control unit 15 processes the first lot L1 in the cleaning processing unit ONB1. This cleaning process using pure water is performed from time t2 to time t6.

[0085] The period from time t2 to time t6 corresponds to the "process of starting the cleaning treatment for the first lot" in the present invention.

[0086] The control unit 15 processes the second lot L2 in the chemical processing unit CHB from time t2 to time t3. The chemical processing of the second lot L2 by the chemical processing unit CHB is completed at time t3. The control unit 15 transports the second lot L2 at time t3 and transports the second lot L2 to the cleaning processing unit ONB2. The control unit 15 processes the second lot L2 in the cleaning processing unit ONB2. This cleaning process using pure water is performed from time t4 to time t8.

[0087] The period from time t4 to time t8 corresponds to the "process of starting the cleaning treatment for the second lot" in the present invention.

[0088] At time t5, control unit 15 starts processing of third lot L3 in chemical processing unit CHB. Chemical processing by chemical processing unit CHB is completed at time t6. Control unit 15 transports third lot L3 from time t6 to time t7, and transports third lot L3 to cleaning processing unit ONB1. Control unit 15 processes third lot L3 in cleaning processing unit ONB1. This cleaning process using pure water is performed from time t7 to time t10.

[0089] The period from time t7 to time t10 corresponds to the "process of starting the cleaning treatment for the third lot" in the present invention.

[0090] The control unit 15 processes the fourth lot L4 in the chemical processing unit CHB from time t7 to time t8. The chemical processing of the fourth lot L4 by the chemical processing unit CHB is completed at time t8. The control unit 15 transports the fourth lot L4 at time t8 and transports the fourth lot L4 to the cleaning processing unit ONB2. The control unit 15 processes the fourth lot L4 in the cleaning processing unit ONB2. This cleaning processing using pure water is performed from time t9 to time t11.

[0091] Next, the reuse of the waste liquid in the cleaning processing unit ONB1 and the cleaning processing unit ONB2 when the first to fourth lots L1 to L4 are processed as described above will be described.

[0092] The first lot L1 being cleaned in the cleaning processing unit ONB1 and the second lot L2 being cleaned in the cleaning processing unit ONB2 are completely overlapped in time from time t4 to time t6 with the entire second half SH of the first lot L1 and the entire first half FH of the second lot L2.

[0093] <5. Recycling Operation>

[0094] <5.1 Recycling from cleaning processing unit ONB1 to cleaning processing unit ONB2> At this time, the control unit 15 performs recycling, for example, as follows from time t4 to time t6.

[0095] That is, from time t4 to time t6, control unit 15 recycles the effluent discharged from outer tank 21 of cleaning unit ONB1 to discharge pipe 37 as follows.

[0096] Specifically, the control unit 15 opens the on-off valve 45 and operates the pump 47. As a result, the discharged liquid discharged from the discharge pipe 37 of the cleaning processing unit ONB1 flows through the recycle pipe 43 and is supplied to the supply pipe 25 of the cleaning processing unit ONB2. At this time, the control unit 15 monitors the output from the flow meter 49 of the recycle pipe 43. It is preferable that the control unit 15 operates the liquid supply amount of the pump 47 so that this output coincides with the target flow rate defined in the recipe.

[0097] At time t6, the control unit 15 closes the on-off valve 45 and stops the pump 47. Furthermore, the control unit 15 opens the on-off valve 31. The control unit 15 operates the flow rate adjustment valve 29 so that the flow rate measured by the flow meter 33 in the cleaning processing unit ONB2 coincides with the target value of the flow rate defined in the recipe.

[0098] The second lot L2 being cleaned in the cleaning processing unit ONB2 and the third lot L3 being cleaned in the cleaning processing unit ONB1 overlap in part of the second half SH of the second lot L2 and part of the first half FH of the third lot L3 from time t7 to time t8.

[0099] <5.2 Recycling from cleaning processing unit ONB2 to cleaning processing unit ONB1> The control unit 15 performs recycling, for example, as follows, from time t7 to time t8.

[0100] That is, from time t7 to time t8, control unit 15 recycles the effluent discharged from outer tank 21 of cleaning unit ONB2 to discharge pipe 37 as follows. Specifically, control unit 15 opens on-off valve 55 and operates pump 57. As a result, the effluent discharged from discharge pipe 37 of cleaning unit ONB2 flows through recycle pipe 53 and is supplied to supply pipe 25 of cleaning unit ONB1. At this time, control unit 15 monitors the output from flow meter 59 of recycle pipe 53. It is preferable that control unit 15 adjusts the amount of liquid sent by pump 57 so that this output coincides with the target flow rate specified in the recipe.

[0101] <5.3 Recycling from cleaning processing unit ONB1 to cleaning processing unit ONB2> From time t9 to time t10, control unit 15 performs recycling in the same manner as in <5.1 Recycling from cleaning unit ONB1 to cleaning unit ONB2> described above. That is, control unit 15 supplies the waste liquid from cleaning unit ONB1 to cleaning unit ONB2 via recycling pipe 43.

[0102] When four lots, from the first lot L1 to the fourth lot L4, are processed sequentially as described above, the amount of pure water saved can be calculated as follows compared to a normal cleaning process that does not recycle pure water. For simplicity, the amount of saved water is shown here as the number of squares that represent the unit time of processing.

[0103] When processing the second lot L2, the recycle pipe 43 can save "7 unit hours" of pure water. When processing the third lot L3, the recycle pipe 53 can save "5 unit hours" of pure water. When processing the fourth lot L4, the recycle pipe 43 can save "7 unit hours" of pure water. In other words, a total of "19 unit hours" of pure water can be saved.

[0104] According to this embodiment, the control unit 15 controls the on-off valves 31 and flow rate adjustment valves 29 of the cleaning unit ONB1 and the cleaning unit ONB2, and the on-off valves 45 and 55 of the recycle pipes 43 and 53, to supply the effluent used in the latter half SH of the cleaning process in the cleaning unit ONB1 to the cleaning unit ONB2, and to supply the effluent used in the latter half SH of the cleaning process in the cleaning unit ONB2 to the cleaning unit ONB1. Since the effluent used in the cleaning unit ONB1 is reused in the cleaning unit ONB2, and the effluent used in the cleaning unit ONB2 is reused in the cleaning unit ONB1, the amount of pure water supplied from the supply pipe 25 to the cleaning unit ONB1 and the cleaning unit ONB2 can be reduced. Therefore, by recycling the pure water, the amount of pure water consumed in the cleaning process can be reduced.

[0105] <Variation 1> Please refer to Fig. 7. Fig. 7 is a diagram showing a modified example of the cleaning processing section.

[0106] The substrate processing apparatus according to the first modification differs from the above-described configuration in that it includes buffer tanks 51 and 61.

[0107] Specifically, the recycle pipe 43 of the cleaning processing unit ONB1 includes a buffer tank 51. The buffer tank 51 is disposed between the on-off valve 45 and the pump 47. The recycle pipe 53 of the cleaning processing unit ONB2 includes a buffer tank 61. The buffer tank 61 is disposed between the on-off valve 55 and the pump 57.

[0108] The buffer tank 51 temporarily stores the effluent discharged from the outer tank 21 of the cleaning processing unit ONB1 to the discharge pipe 37 and flowing into the recycle pipe 43. The buffer tank 61 temporarily stores the effluent discharged from the outer tank 21 of the cleaning processing unit ONB2 to the discharge pipe 37 and flowing into the recycle pipe 53.

[0109] Providing buffer tanks 51 and 61 in this way allows for a margin in the timing for recycling and supplying the discharged liquid, which allows for the discharged liquid to be reused appropriately even if there is a time lag between the second half SH of the previously introduced lot and the first half FH of the subsequently introduced lot.

[0110] A more specific explanation will be given below. Referring now to Figure 6, the latter half SH of the second lot L2 is located from time t6 to time t8. The first half FH of the third lot L3 is located from time t7 to time t9. Therefore, in the configuration of this embodiment, of the latter half SH of the second lot L2 (times t6 to t8), only the discharged liquid from time t7 to t8 can be reused.

[0111] Therefore, with the configuration of this modified example 1, since the buffer tank 61 is provided, the discharged liquid from the latter half SH of the second lot L2 at times t6 to t7 can be temporarily stored in the buffer tank 61. Therefore, all of the discharged liquid from the latter half SH of the second lot L2 can be reused in the first half FH of the third lot L2.

[0112] <Variation 2> Please refer to Fig. 8. Fig. 8 is a diagram showing another modified example of the cleaning processing section.

[0113] In the above-described configuration, the substrate processing apparatus is provided with two cleaning processors, namely, cleaning processor ONB1 and cleaning processor ONB2. Modification 2 shows an example of a configuration in which a cleaning processor ONBx is further provided.

[0114] In this configuration, a recycle pipe 63 is provided, one end of which is connected to the recycle pipe 43 of the cleaning processing unit ONB1. A recycle pipe 73 is also provided, one end of which is connected to the recycle pipe 53 of the cleaning processing unit ONB2. The other ends of these recycle pipes 63, 73 are connected to the supply pipes of the cleaning processing unit ONBx. The recycle pipe 63 is provided with an on-off valve 65. The on-off valve 65 allows or blocks the flow of the discharge liquid from the cleaning processing unit ONB1 through the recycle pipe 43 in the recycle pipe 63. The recycle pipe 73 is provided with an on-off valve 75. The on-off valve 75 allows or blocks the flow of the discharge liquid from the cleaning processing unit ONB2 through the recycle pipe 53 in the recycle pipe 73.

[0115] Furthermore, cleaning processing unit ONB1 is equipped with a recycle pipe 83, one end of which is connected to supply pipe 25. Cleaning liquid supply unit ONB2 is equipped with a recycle pipe 93, one end of which is connected to supply pipe 25. The other ends of recycle pipes 83 and 93 are connected to discharge pipe 37 (not shown) of cleaning processing unit ONBx. Recycle pipes 83 and 93 are equipped with open / close valves (not shown). This allows for mutual reuse of discharged liquid from each unit, even when cleaning processing unit ONBx is provided in addition to cleaning processing units ONB1 and ONB2.

[0116] The present invention is not limited to the above-described embodiment, but can be modified as follows.

[0117] (1) In the above-described embodiment, the recycle pipe 43 and the recycle pipe 53 are provided, but the present invention is not limited to such a configuration. For example, a configuration may be adopted in which only one of the recycle pipe 43 and the recycle pipe 53 is provided. Even with such a configuration, the amount of pure water consumed by either the cleaning processing unit ONB1 or the cleaning processing unit ONB2 can be reduced.

[0118] (2) In the above-described embodiment, an example has been described in which the substrate processing apparatus includes transport mechanisms such as the first transport mechanism CTC and the second transport mechanism WTR, and a drying processor LPD, as shown in Fig. 1. However, such a configuration is not essential to the present invention. In other words, the present invention can be applied to any substrate processing apparatus that includes at least two cleaning processors, namely, cleaning processor ONB1 and cleaning processor ONB2.

[0119] (3) In the above-described embodiment, the supply pipe 25 is configured to supply only pure water. However, the present invention may be configured such that the supply pipe 25 is provided with a mixing valve. The mixing valve is made up of a plurality of mixing valves, and multiple types of chemical liquids can be mixed in the supply pipe 25. When such a configuration is adopted, only pure water, a processing liquid obtained by mixing pure water with a chemical liquid, or a processing liquid consisting of only a chemical liquid can be supplied through the supply pipe 25. The present invention is applicable even to such a configuration.

[0120] (4) In the above-described embodiment, when the waste liquid can be reused for cleaning, the pure water supplied from the supply pipe 25 to the inner tank 19 in the first half FH of the cleaning processing unit ONB2 is supplied solely from the waste liquid in the recycle pipe 43. However, the present invention is not limited to this configuration.

[0121] That is, control unit 15 controls the supply amount of pure water through supply pipe 25 of cleaning unit ONB2 and the supply amount of pure water discharged from discharge pipe 37 of cleaning unit ONB1 through recycle pipe 43.

[0122] Specifically, new pure water from the pure water supply source 27 of the cleaning unit ONB2 and the discharged liquid from the recycle pipe 43 are appropriately mixed and supplied to the inner tank 19. More specifically, for the cleaning unit ONB2, the control unit 15 operates the on-off valve 31 and the flow rate adjustment valve 29 in the supply pipe 25 and the on-off valve 45 and the pump 47 in the recycle pipe 43. At this time, it is preferable to perform feedback control by referring to the flow rates measured by the flow meters 33 and 49. This allows the control unit 15 to mix the discharged liquid from the latter half SH of the cleaning unit ONB1 with the new pure water from the cleaning unit ONB2 and reuse it for cleaning in the first half FH of the cleaning unit ONB2. Similarly, the discharged liquid from the latter half SH of the cleaning unit ONB2 can be mixed with the new pure water from the cleaning unit ONB1 and reused for cleaning in the first half FH of the cleaning unit ONB1.

[0123] This increases the proportion of clean pure water, which is expected to reduce the cleaning time while saving pure water.

[0124] When the above-mentioned mixing is performed, it is preferable that the control unit 15 operates each unit as follows.

[0125] That is, for example, the control unit 15 adjusts the flow rate control valve 29 of the cleaning unit ONB2 performing the first half FH of the cleaning process, while taking into consideration the flow rate of the waste liquid flowing in from the recycle pipe 43. That is, for the cleaning unit ONB2 performing the first half FH of the cleaning process, the control unit 15 operates the flow rate control valve 29 and the pump 47 so that the flow rate of pure water supplied from the jet pipe 23 to the inner tank 19 approximately matches the flow rate of pure water in the first half FH or the second half SH when no recycling is performed. When the cleaning unit ONB1 is performing the second half SH of the cleaning process, the control unit 15 operates the flow rate control valve 29 of the cleaning unit ONB2 and the pump 47 of the recycle pipe 43 so that the flow rate of pure water supplied from the jet pipe 23 to the inner tank 19 of the cleaning unit ONB2 approximately matches the flow rate of pure water supplied to the first half FH of the cleaning unit ONB2 or the flow rate of pure water supplied to the second half SH of the cleaning unit ONB2 when no recycling is performed.

[0126] This prevents the flow of pure water in the inner bath 19 from suddenly fluctuating in the first half FH and the second half SH of the cleaning process, thereby preventing adverse effects on the substrates W being processed in the processing position of the inner bath 19.

[0127] (5) In the above-described embodiment, the recycle pipes 43, 53 are connected in communication with the supply pipe 25. However, the present invention is not limited to this configuration. The recycle pipes 43, 54 may be connected in communication with the ejection pipe 23 or the inner tank 19.

[0128] (6) In the above-described embodiment, the first half FH and the second half SH are separated at time t1 when the resistivity SR1 reaches 0.5 to 1 MΩ·cm. However, the present invention is not limited to this configuration. In other words, if the cleanliness of the substrate on the side receiving the recycled effluent is significantly lower than the cleanliness of the substrate on the side receiving the recycled effluent, the first half FH and the second half SH may be separated at a point when the resistivity SR1 is lower than 0.5 to 1 MΩ·cm. Furthermore, the resistivity SR1 of 0.5 to 1 MΩ·cm is merely an example, and the present invention is not limited to this value.

[0129] (7) In the above-described embodiment, the inner bath 19 is provided with a resistivity meter 35. However, the present invention is not limited to this configuration. For example, instead of the resistivity meter 35, a conductivity meter may be used that is more sensitive to cleanliness than the resistivity meter 35, even when there are many impurities. This allows the cleaning level of the substrate W to be determined more accurately. As a result, the control unit 15 can accurately determine when the second SH has been reached. Therefore, the control unit 15 may start recycling in the second SH based on the conductivity in the inner bath 19, rather than starting recycling in the second SH at a predetermined time. This allows flexible processing according to the cleanliness level, without being limited by time.

[0130] (8) In the above-described embodiment, an example was described in which four lots were processed. However, the present invention is not limited to such a process. In other words, the present invention is effective when at least two lots are processed. [Industrial Applicability]

[0131] As described above, the present invention is suitable for a substrate processing apparatus that performs a cleaning process on a substrate. [Explanation of symbols]

[0132] W: Substrate CTC: First transport mechanism WTR: Second transport mechanism LPD: Drying processing section 11 ... First processing section ONB1: Cleaning processing section CHB1: Chemical treatment unit LFS1: Sub-transport mechanism 13 ... Second processing section ONB2: Cleaning processing section CHB2: Chemical treatment unit LFS2: Sub-transport mechanism 15...Control section 17... Treatment tank 19 … Inner tank 21 … Outer tank 23 … Ejection pipe 25 … Supply pipe 27 … Pure water supply pipe 29... Flow control valve 31...Shut-off valve 33…Flowmeter 35…Resistivity meter 37 … Discharge pipe 43,53 ... Recycled pipes L1~L4 ... 1st lot to 4th lot FH: First half SH... second half 51,61 ... Buffer tank

Claims

1. A substrate processing apparatus for performing a cleaning process on a substrate, a first processing tank capable of accommodating a substrate; a second processing tank capable of accommodating a substrate; a first pure water supply pipe connected in communication with a pure water supply source and supplying pure water to the first treatment tank; a first supply valve inserted in the first pure water supply pipe; a second pure water supply pipe connected in communication with a pure water supply source and supplying pure water to the second treatment tank; a second supply valve inserted in the second pure water supply pipe; a first recycle pipe for supplying the effluent discharged from the first treatment tank to the second treatment tank; a first recycle valve inserted in the first recycle pipe; a control unit that controls opening and closing of the first supply valve, the second supply valve, and the first recycle valve; A substrate processing apparatus comprising:

2. 2. The substrate processing apparatus according to claim 1, a second recycle pipe that supplies the effluent discharged from the second treatment tank to the first treatment tank; a second recycle valve inserted in the second recycle pipe; Furthermore, The substrate processing apparatus is characterized in that the control unit further controls opening and closing of the second recycle valve.

3. 3. The substrate processing apparatus according to claim 1, The control unit manages substrates to be cleaned by lot, and when a first lot is cleaned in the first processing tank and a second lot is cleaned in the second processing tank, at least a portion of the discharged liquid discharged from the first processing tank in the latter half of the cleaning process of the first lot is supplied to the second processing tank through the first recycle pipe in the first half of the cleaning process of the second lot.

4. 3. The substrate processing apparatus according to claim 2, the control unit manages substrates to be cleaned by lot, and when a first lot is cleaned in the first processing tank and a second lot is cleaned in the second processing tank, at least a part of a discharged liquid discharged from the first processing tank in the latter half of the cleaning processing of the first lot is supplied to the second processing tank through the first recycling pipe in the first half of the cleaning processing of the second lot; A substrate processing apparatus characterized in that at least a portion of the discharged liquid discharged from the second processing tank in the latter half of the cleaning process of the second lot is supplied to the first processing tank through the second recycling pipe in the first half of the cleaning process of a third lot that is processed in the first processing tank following the first lot.

5. 3. The substrate processing apparatus according to claim 2, the first processing tank includes a first inner tank capable of accommodating a substrate, a first ejection pipe provided at the bottom of the first inner tank and ejecting pure water upward, and a first outer tank into which a discharged liquid overflowing from an upper edge of the first inner tank flows; the first pure water supply pipe is connected in communication with the first jet pipe and the second recycle pipe; the second processing tank includes a second inner tank capable of accommodating a substrate, a second ejection pipe provided at the bottom of the second inner tank and ejecting pure water upward, and a second outer tank into which discharged liquid overflowing from an upper edge of the second inner tank flows; The substrate processing apparatus is characterized in that the second pure water supply pipe is connected in communication with the second jet pipe and the first recycle pipe.

6. 5. The substrate processing apparatus according to claim 3, The substrate processing apparatus is characterized in that the latter half of the cleaning process for the first lot is the time from the start of the cleaning process until the resistivity exceeds 0.5 to 1 MΩ·cm.

7. 4. The substrate processing apparatus according to claim 3, The control unit does not supply waste liquid discharged from the first processing tank to the second processing tank during the latter half of the cleaning process of the second lot, and instead supplies pure water from the second pure water supply pipe to the second processing tank.

8. 5. The substrate processing apparatus according to claim 4, The control unit mixes at least a portion of the discharged liquid discharged from the first processing tank with the pure water flowing through the second pure water supply pipe and supplies the resultant mixture to the second processing tank during the first half of the cleaning process of the second lot, and mixes at least a portion of the discharged liquid discharged from the second processing tank with the pure water flowing through the first pure water supply pipe and supplies the resultant mixture to the first processing tank during the first half of the cleaning process of the third lot.

9. 2. The substrate processing apparatus according to claim 1, The substrate processing apparatus is characterized in that the first recycle pipe is provided with a buffer tank.

10. 3. The substrate processing apparatus according to claim 2, The substrate processing apparatus is characterized in that the second recycle pipe is provided with a buffer tank.

11. A substrate processing method for performing a cleaning process on a substrate, comprising: a step of starting a cleaning process for a first lot in a first processing tank capable of accommodating substrates when the substrates to be cleaned are managed by lot; after the step of starting the cleaning process for the first lot, starting a cleaning process for a second lot in a second processing tank capable of accommodating substrates; When performing the following in that order, A substrate processing method comprising the steps of: supplying at least a portion of a liquid discharged from the first processing tank to the second processing tank.

12. 12. The substrate processing method according to claim 11, When a step of starting a cleaning process for a third lot to be processed in the first processing tank following the first lot is performed after the step of starting the cleaning process for the second lot, A substrate processing method comprising the steps of: supplying at least a portion of a liquid discharged from the second processing tank to the first processing tank.

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