Substrate processing apparatus and substrate processing method

Abstract

A substrate processing apparatus and a substrate processing method capable of suppressing an increase in particles are provided. The substrate processing apparatus includes a tank, a circulation line, a branch line, a processing section, a discharge section, a supply section, and a control section. The control section includes a first determination section, a first replenishment control section, a calculation section, and a second replenishment control section. The first determination section determines whether a storage amount of the processing liquid in the tank is less than a lower limit value. In a case where the first determination section determines that the storage amount is less than the lower limit value, the first replenishment control section replenishes the processing liquid to the tank through the supply section. The calculation section calculates a replenishment amount of the processing liquid to the tank through the supply section per set time. In a case where a calculated value of the replenishment amount calculated by the calculation section is less than a set value, the second replenishment control section reduces the storage amount of the tank through the discharge section and replenishes the processing liquid to the tank through the supply section.

Description

Technical Field

[0001] This disclosure relates to a substrate processing apparatus and a substrate processing method. Background Technology

[0002] Patent Document 1 discloses a substrate processing system comprising one or more processing units, a storage unit, a liquid storage unit, an acquisition unit, a setting unit, a detection unit, an identification unit, and a detection unit. One or more processing units process the substrate using a processing liquid. The storage unit stores processing plan information indicating the execution timing of multiple consecutive processes related to multiple substrate groups within the one or more processing units. The liquid storage unit stores the processing liquid. The acquisition unit acquires values ​​related to the state of the processing liquid. The setting unit sets the replacement period of the processing liquid in the liquid storage unit based on the values ​​acquired by the acquisition unit and rules related to the lifespan of the processing liquid. The detection unit detects a standby state during the replacement period where continuous processing has not been performed by one or more processing units. The identification unit identifies the duration of the standby state based on the processing plan information. The detection unit detects a liquid-replaceable state where the duration is longer than a preset reference time.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-181881 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] The first aspect of this disclosure provides a technique for suppressing the increase of particulate matter caused by the circulation of the treatment fluid. Furthermore, the second aspect of this disclosure provides a technique for suppressing the increase of particulate matter caused by the replacement of the treatment fluid.

[0008] Solution for solving the problem

[0009] The substrate processing apparatus according to the first aspect of this disclosure includes a tank, a circulation line, a branch line, a processing unit, a discharge unit, a supply unit, and a control unit. The tank is used to store a processing liquid. The circulation line is used to remove the processing liquid from the tank and return it to the tank. The branch line branches off from the circulation line. The processing unit supplies the processing liquid to the substrate through the front end of the branch line. The discharge unit reduces the amount of processing liquid stored in the tank. The supply unit supplies new processing liquid to the tank. The control unit controls the processing unit, the discharge unit, and the supply unit. The control unit includes a first determination unit, a first replenishment control unit, a calculation unit, and a second replenishment control unit. The first determination unit determines whether the amount of processing liquid stored in the tank is less than a lower limit. If the first determination unit determines that the amount of processing liquid is less than the lower limit, the first replenishment control unit replenishes the tank with processing liquid through the supply unit. The calculation unit calculates the amount of processing liquid replenished to the tank through the supply unit at set intervals. If the calculated value of the replenishment amount obtained by the calculation unit is less than the set value, the second replenishment control unit reduces the storage amount in the tank through the discharge unit and replenishes the treatment liquid to the tank through the supply unit.

[0010] The substrate processing apparatus according to the second aspect of this disclosure includes a tank, a circulation line, a pump, a branch line, a processing unit, a discharge unit, a supply unit, and a control unit. The tank stores processing liquid. The circulation line is used to remove the processing liquid from the tank and return it to the tank. The pump is provided on the circulation line. The branch line branches off from the circulation line. The processing unit supplies the processing liquid to the substrate through the front end of the branch line. The discharge unit reduces the amount of processing liquid stored in the tank. The supply unit supplies new processing liquid to the tank. The control unit controls the pump, the processing unit, the discharge unit, and the supply unit. The control unit has a first liquid replacement control unit. When the first liquid replacement control unit receives a liquid replacement command to replace the processing liquid in the circulation, while the processing liquid is being circulated by the pump, the first liquid replacement control unit performs the process of reducing the amount stored in the tank by the discharge unit and the process of supplying the processing liquid to the tank by the supply unit.

[0011] The effects of the invention

[0012] According to the first aspect of this disclosure, the increase of particles caused by the circulation of the treatment fluid can be suppressed. Furthermore, according to the second aspect of this disclosure, the increase of particles caused by the replacement of the treatment fluid can be suppressed. Attached Figure Description

[0013] Figure 1This is a diagram illustrating a substrate processing apparatus according to one embodiment.

[0014] Figure 2 This is a diagram showing an example of a processing unit.

[0015] Figure 3 This diagram illustrates an example of the structural elements of the control unit using function blocks.

[0016] Figure 4 This is a flowchart illustrating an example of the processing of the substrate processing unit.

[0017] Figure 5 This is a flowchart illustrating an example of the processing of the first determination unit and the first supplementary control unit.

[0018] Figure 6 This is a diagram illustrating an example of the relationship between the number of particles attached to the substrate, the cycle time, and the temperature of the processing solution.

[0019] Figure 7 Figure (A) is an example of the treatment liquid at the start of a cycle. Figure 7 Figure (B) is a diagram showing an example of leaching from the filter. Figure 7 (C) is a diagram showing an example of the passage of dissolved components. Figure 7 (D) is a diagram showing an example of the replenishment and discharge of the treatment fluid.

[0020] Figure 8 This is a flowchart illustrating an example of the processing of the calculation unit and the second supplementary control unit.

[0021] Figure 9 It is shown Figure 8 A figure showing an example of the processing results.

[0022] Figure 10 This is a diagram illustrating an example of the relationship between the number of particles attached to the substrate, the cycle time, and the replenishment amount R.

[0023] Figure 11 This is a flowchart illustrating an example of the processing of the second fluid replacement control unit.

[0024] Figure 12 This is a flowchart illustrating an example of the processing of the first fluid replacement control unit.

[0025] Figure 13 This is a graph illustrating an example of the relationship between the number of fluid replacements and the proportion of new fluid.

[0026] Figure 14 This is a diagram illustrating an example of the number of particles adhering to the substrate after the contact fluid is replaced.

[0027] Figure 15This is a diagram illustrating the substrate processing apparatus involved in the modified example. Detailed Implementation

[0028] The embodiments of this disclosure will now be described with reference to the accompanying drawings. Furthermore, in the various drawings, the same or corresponding structures are labeled with the same reference numerals, and sometimes descriptions are omitted.

[0029] Reference Figure 1 The substrate processing apparatus 1 according to this embodiment will be described below. The substrate processing apparatus 1 includes a processing unit 10. The processing unit 10 processes the substrate by supplying a processing liquid to the substrate. In this embodiment, the processing unit 10 is a monolithic type that processes substrates one by one.

[0030] Furthermore, the processing unit 10 can also be a batch processing unit that processes multiple substrates simultaneously. The batch processing unit 10 has a processing tank in which the substrates are immersed in a processing solution stored. In this case, the substrates W can also be immersed in the processing solution in a vertically upright position.

[0031] like Figure 2 As shown, the monolithic processing unit 10 includes, for example: a processing container 11; a holding part 12 that holds the substrate W horizontally; a rotating part 13 that rotates the holding part 12 about a vertical rotation axis 14; and a nozzle 16 that sprays liquid onto the upper surface of the substrate W held in the holding part 12.

[0032] The processing container 11 houses the substrate W inside. The processing container 11 has a door (not shown) and a gate valve (not shown) for opening and closing the door. The substrate W is moved into the processing container 11 through the door, processed inside the processing container 11 using a processing liquid L, and then moved out of the processing container 11 through the door.

[0033] The holding part 12 holds the substrate W horizontally inside the processing container 11. The holding part 12 holds the substrate W horizontally with the surface of the substrate W where the polysilicon film is formed facing upwards and with the center of the substrate W aligned with the rotation center line of the rotation axis 14. Figure 2 In this chuck, the holding part 12 is a mechanical chuck, but it can also be a vacuum chuck or an electrostatic chuck, etc. The holding part 12 can be any rotary chuck that can rotate.

[0034] The rotating part 13 includes, for example, a vertical rotating shaft 14 and a rotary motor 15 that rotates the rotating shaft 14. The rotational driving force of the rotary motor 15 can be transmitted to the rotating shaft 14 via a transmission mechanism such as a timing belt or gears. When the rotating shaft 14 is rotated, the holding part 12 also rotates.

[0035] The nozzle 16 has an outlet for spraying the processing liquid L onto the substrate W held in the holding portion 12. The nozzle 16 is positioned above the substrate W, for example, with the outlet facing downwards, and supplies the processing liquid L to the center of the substrate W. The processing liquid L is supplied to the center of the rotating substrate W and diffuses through centrifugal force to wet the entire upper surface of the substrate W, thereby forming a liquid film. The processing portion 10 may also include a moving portion 19 for moving the nozzle 16. The moving portion 19 can move the nozzle 16 radially along the substrate W or vertically.

[0036] The processing liquid L may include, for example, a chemical solution, a rinsing solution, and a drying solution. Multiple processing liquids L can be sprayed sequentially from a single nozzle 16, or multiple nozzles 16 can spray different processing liquids L sequentially. Multiple chemical solutions can be supplied to the substrate W sequentially, or a rinsing solution can be supplied to the substrate W between the supply of multiple chemical solutions.

[0037] The solution can be DHF (dilute hydrofluoric acid), SC-1 (an aqueous solution containing ammonium hydroxide and hydrogen peroxide), SC-2 (an aqueous solution containing hydrogen chloride and hydrogen peroxide), or SPM (an aqueous solution containing sulfuric acid and hydrogen peroxide), etc., but there are no particular limitations. The solution can also be an etching solution for etching the substrate W.

[0038] The rinsing solution is, for example, DIW (deionized water). The rinsing solution is used to remove the chemical solution. The rinsing solution is supplied to the center of the rotating substrate W and diffuses by centrifugal force in a manner that wets the entire upper surface of the substrate W, thereby rinsing away any remaining chemical solution on the upper surface of the substrate W. As a result, a liquid film of the rinsing solution is formed on the upper surface of the substrate W. Alternatively, the rinsing solution can be supplied to the substrate W after one chemical solution has been supplied and before other chemical solutions have been supplied.

[0039] The drying solution is, for example, an organic solvent such as IPA (isopropanol). Organic solvents have a lower surface tension than the rinsing solution. Therefore, it is possible to suppress the collapse of the raised pattern caused by surface tension. The drying solution is supplied to the center of the rotating substrate W and diffuses by centrifugal force in a manner that wets the entire upper surface of the substrate W, thereby displacing the rinsing solution remaining on the upper surface of the substrate W. As a result, a liquid film of drying solution is formed on the upper surface of the substrate W.

[0040] The processing unit 10 has a cup 17 for recovering the processing liquid L supplied to the substrate W. The cup 17 surrounds the periphery of the substrate W held in the holding unit 12 and receives the processing liquid L that spills from the periphery of the substrate W. In this embodiment, the cup 17 does not rotate with the rotation axis 14, but the cup 17 may rotate with the rotation axis 14. A drain pipe 17a and an exhaust pipe 17b are provided on the bottom wall of the cup 17. The drain pipe 17a is used to discharge the liquid accumulated inside the cup 17, and the exhaust pipe 17b is used to discharge the gas accumulated inside the cup 17.

[0041] like Figure 1 As shown, the substrate processing apparatus 1 includes: a tank 20 for storing processing liquid L; a circulation line 21 for removing processing liquid L from the tank 20 and returning processing liquid L to the tank 20; and a branch line 22 that branches off from the circulation line 21. The processing unit 10 supplies processing liquid L to the substrate W through the front end of the branch line 22. The processing liquid L is, for example, IPA, but is not particularly limited thereto.

[0042] Tank 20 is used to store the treatment fluid L. The treatment fluid L circulates from tank 20 to tank 20 via circulation line 21. Along circulation line 21, for example, a pump 23, a flow meter 24, a heater 25, a thermometer (not shown), and a filter 26 are installed. Furthermore, the configuration of these devices 23-26 is not limited to... Figure 1 Configuration.

[0043] Pump 23 circulates the processing fluid L. Flow meter 24 measures the flow rate of the processing fluid L. Control unit 90 controls pump 23 to make the flow meter 24 reading a set value. Heater 25 heats the processing fluid L. Thermometer measures the temperature of the processing fluid L. Control unit 90 controls heater 25 to make the thermometer reading a set value. Processing fluid L at the desired temperature can be supplied to substrate W. Filter 26 captures foreign matter in the processing fluid L.

[0044] Branch line 22 connects circulation line 21 to nozzle 16 of processing unit 10. A branch line 22 is provided for each processing unit 10. Furthermore, in the case of batch processing units 10, branch line 22 connects circulation line 21 to processing tank of processing unit 10. A flow meter 27, flow controller 28, and on / off valve 29 are provided, for example, along the branch line 22. Moreover, the configuration of these devices 27-29 is not limited to... Figure 1 Configuration.

[0045] When the on / off valve 29 opens the branch line 22, the branch line 22 supplies the processing fluid L to the processing unit 10. The flow meter 27 measures the flow rate of the processing fluid L. The control unit 90 controls the flow controller 28 so that the measurement value of the flow meter 27 becomes the set value. On the other hand, when the on / off valve 29 closes the branch line 22, the branch line 22 stops supplying the processing fluid L to the processing unit 10.

[0046] Alternatively, a return line 30 can be installed midway through the branch line 22. The return line 30 branches off from the branch line 22 to return the processed liquid L to the tank 20. A return line 30 is provided for each processing unit 10. For example, an on / off valve 31 is installed midway through the return line 30.

[0047] When the on / off valve 29 closes the branch line 22 and the on / off valve 31 opens the return line 30, the processing liquid L is not supplied to the processing section 10 and returns to the tank 20. Even when the processing section 10 is not consuming the processing liquid L, the processing liquid L heated by the heater 25 can continue to flow in a portion of the branch line 22, thereby suppressing the temperature drop of the processing liquid L in the branch line 22.

[0048] On the other hand, when the on / off valve 29 opens the branch line 22 and the on / off valve 31 closes the return line 30, the processing liquid L does not return to the tank 20 but is supplied to the processing unit 10. The processing liquid L supplied to the processing unit 10 is consumed in the processing unit 10. That is, the processing liquid L supplied to the processing unit 10 is discharged to the outside of the substrate processing apparatus 1 and does not return to the tank 20. As a result, the storage amount H of the processing liquid L stored in the tank 20 decreases.

[0049] In addition to the processing unit 10, the substrate processing apparatus 1 also includes a discharge unit 40 for reducing the storage amount H of the processing liquid L. For example, when the processing liquid L is replaced to suppress its deterioration, the discharge unit 40 reduces the storage amount H of the processing liquid L. The discharge unit 40 includes, for example, a first discharge unit 41 and a second discharge unit 42. Furthermore, the discharge unit 40 may include only the first discharge unit 41 or only the second discharge unit 42.

[0050] The first discharge section 41 includes a first discharge line 43 connected to the tank 20 and a first on / off valve 44 for opening and closing the first discharge line 43. When the first on / off valve 44 opens the first discharge line 43, the first discharge line 43 discharges the processed liquid L from the tank 20, thereby reducing the storage volume H of the processed liquid L. On the other hand, when the first on / off valve 44 closes the first discharge line 43, the first discharge line 43 stops discharging the processed liquid L from the tank 20.

[0051] The second discharge section 42 includes a second discharge line 45 connected to the circulation line 21 and a second on / off valve 46 for opening and closing the second discharge line 45. When the second on / off valve 46 opens the second discharge line 45, the second discharge line 45 discharges the treatment liquid L from the circulation line 21, thereby reducing the storage amount H of the treatment liquid L. On the other hand, when the second on / off valve 46 closes the second discharge line 45, the second discharge line 45 stops discharging the treatment liquid L from the circulation line 21.

[0052] The substrate processing apparatus 1 includes a supply unit 50 for supplying new processing liquid L to a tank 20. The supply unit 50 includes a supply line 51 connected to the tank 20. New processing liquid L is replenished into the tank 20 via the supply line 51. A flow meter 52, a flow controller 53, and an on / off valve 54 are provided, for example, along the supply line 51. Furthermore, the configuration of these devices 52 to 54 is not limited to... Figure 1Configuration.

[0053] When the on / off valve 54 opens the supply line 51, the supply line 51 supplies new processing fluid L to the tank 20. The flow meter 52 measures the flow rate of the processing fluid L. The control unit 90 controls the flow controller 53 to make the measurement value of the flow meter 52 equal to the set value. On the other hand, when the on / off valve 54 closes the supply line 51, the supply line 51 stops supplying new processing fluid L to the tank 20.

[0054] The substrate processing apparatus 1 includes multiple detectors 61 to 64 for detecting the storage level H of the processing liquid L in the tank 20. The multiple detectors 61 to 64 are positioned at different heights to detect the presence of the processing liquid L at their respective positions. Furthermore, although not shown, the substrate processing apparatus 1 may also include a floating detector, and the number of detectors may also be one.

[0055] The substrate processing apparatus 1 includes a control unit 90. The control unit 90 is, for example, a computer, and includes a CPU (Central Processing Unit) 91 and a storage medium 92 such as a memory. The storage medium 92 stores programs for controlling various processes executed in the substrate processing apparatus 1. The control unit 90 controls the operation of the substrate processing apparatus 1 by causing the CPU 91 to execute the programs stored in the storage medium 92.

[0056] like Figure 3 As shown, the control unit 90 includes, for example, a substrate processing unit 101, a first determination unit 102, a first supplementary control unit 103, a calculation unit 104, a second supplementary control unit 105, a second determination unit 106, a forced stop unit 107, a first liquid replacement control unit 108, and a second liquid replacement control unit 109. Furthermore, Figure 3 The functional blocks shown in the diagram are conceptual and may not necessarily be physically constructed as shown.

[0057] Able to Figure 3 All or part of the functional blocks illustrated are functionally or physically distributed / unified in any unit. All or part of the processing functions performed by each functional block can be implemented by a program executed by the CPU or as hardware based on wiring logic.

[0058] Next, refer to Figure 4 Here is an example of the processing of the substrate processing unit 101. Figure 4 Each step S101 to S106 shown is performed under the control of the substrate processing unit 101. The substrate processing unit 101 processes the substrate W by supplying processing liquid L to the substrate W.

[0059] First, a conveying device (not shown) moves the substrate W into the processing container 11 (step S101). After placing the substrate W on the holding part 12, the conveying device withdraws from the processing container 11. The holding part 12 holds the substrate W. Then, the rotating part 13 rotates the substrate W together with the holding part 12.

[0060] Next, nozzle 16 supplies the liquid medicine to the center of the rotating substrate W (step S102). The liquid medicine spreads by centrifugal force to wet the entire upper surface of the substrate W, thereby forming a liquid film.

[0061] Next, nozzle 16 supplies rinsing fluid to the center of the rotating substrate W (step S103). The rinsing fluid spreads by centrifugal force to wet the entire upper surface of the substrate W, thereby rinsing away any residual medication on the upper surface of the substrate W. As a result, a liquid film of rinsing fluid is formed on the upper surface of the substrate W.

[0062] Next, nozzle 16 supplies drying liquid to the center of the rotating substrate W (step S104). The drying liquid spreads by centrifugal force to wet the entire upper surface of the substrate W, thereby rinsing away the rinsing liquid remaining on the upper surface of the substrate W. As a result, a liquid film of drying liquid is formed on the upper surface of the substrate W.

[0063] Next, the rotating part 13 rotates the substrate W to remove the remaining drying liquid on the upper surface of the substrate W, thereby drying the substrate W (step S105). After the substrate W is dried, the rotating part 13 stops the substrate W from rotating.

[0064] Finally, the holding part 12 releases its grip on the substrate W. Next, a conveying device (not shown) receives the substrate W from the holding part 12 and moves the received substrate W to the outside of the processing container 11 (step S106).

[0065] Next, refer to Figure 5 Here is an example illustrating the processing of the first determination unit 102 and the first replenishment control unit 103. During the circulation of the processing liquid L, the following steps are performed periodically: Figure 5 The steps S201 and subsequent processing are shown.

[0066] First, the first determination unit 102 determines whether the storage volume H of the processing liquid L in the tank 20 is less than the lower limit value Hmin (step S201). In this determination, for example, using... Figure 1 The detector 63 shown.

[0067] If the detector 63 does not detect the presence of the processing liquid L, the first determination unit 102 determines that the storage amount H is less than the lower limit value Hmin. On the other hand, if the detector 63 detects the presence of the processing liquid L, the first determination unit 102 determines that the storage amount H is greater than or equal to the lower limit value Hmin.

[0068] If the first determination unit 102 determines that the storage quantity H is less than the lower limit value Hmin (step S201: "Yes"), the first replenishment control unit 103 replenishes the tank 20 with new processing liquid L through the supply unit 50 (step S202). As a result, the storage quantity H becomes greater than or equal to the lower limit value Hmin.

[0069] The first replenishment control unit 103 can replenish new processing fluid L to ensure that the storage volume H is above the lower limit Hmin and below the upper limit Hmax. Figure 1 The detector 64 shown is used to detect when the storage amount H reaches the upper limit value Hmax.

[0070] On the other hand, if the first determination unit 102 determines that the storage amount H is above the lower limit Hmin (step S201: "No"), the first replenishment control unit 103 does not replenish new processing liquid L. After that, the current processing ends.

[0071] Even if the processing unit 10 consumes the processing fluid L, the first replenishment control unit 103 will replenish the processing fluid L to maintain the storage level H of the tank 20 at a certain level or above. The storage level H of the tank 20 is maintained within the allowable range specified by the lower limit Hmin and the upper limit Hmax.

[0072] Next, refer to Figure 6 This example illustrates the relationship between the number of particles adhering to substrate W, the cycle time, and the temperature of the processing solution. The cycle time will be discussed later. Figure 11 The elapsed time from step S404, i.e., the elapsed time from the completion of the liquid replacement process. Details of the liquid replacement process will be described later. Figure 6 In this process, the treatment fluid is IPA.

[0073] like Figure 6 As shown, after the immediate fluid replacement treatment, the longer the circulation time, the more progress the filtration makes, and the fewer particles adhere to the substrate W. Filtration refers to... Figure 7 As shown in (A), the particulate P contained in the treatment liquid L is captured by filter 26.

[0074] like Figure 6 As shown, when the temperature of the processing solution L is room temperature or 60°C, the number of particles adhering to the substrate W gradually decreases and then plateaus. On the other hand, when the temperature of the processing solution L is 70°C, the number of particles adhering to the substrate W sometimes increases after gradually decreasing. It is believed that as the temperature of the processing solution L increases, such as... Figure 7 As shown in (B), the leachate E is dissolved from the filter 26 in the processing solution L, and the leachate E adheres to the substrate W as particles. The higher the temperature of the processing solution L, the easier it is for the leachate E to dissolve, and the more particles adhere to the substrate W.

[0075] For example, the leachate E dissolves in the processing solution L, and after passing through filter 26, it precipitates as particulate matter on the substrate W. Alternatively, the leachate E does not dissolve in the processing solution L but has a particle size sufficient to pass through filter 26. In summary, as Figure 7 As shown in (C), the leachate E passes through filter 26. It is believed that the longer the circulation time, the more leachate E accumulates, and the number of particles adhering to the substrate W increases.

[0076] Furthermore, the device that generates leachate E is not limited to filter 26. Any device installed in circulation line 21 may generate leachate E in the processing liquid L. The relationship between the number of particles adhering to substrate W, circulation time, and temperature of processing liquid L varies depending on the composition of processing liquid L and the material of the device.

[0077] In this embodiment, such as Figure 7 As shown in (D), the treatment liquid L contaminated with leachate E is discharged, and new treatment liquid L is replenished to tank 20 instead. This inhibits the adhesion of leachate E as particulate matter to the substrate W, thereby suppressing the increase in particulate matter caused by the circulation of treatment liquid L.

[0078] Next, refer to Figure 8 Here is an example of the processing of the calculation unit 104 and the second supplementary control unit 105. Figure 8 The steps S301 and subsequent processing shown are as follows: Figure 5 The steps S201 and subsequent processes shown are performed in parallel and during the circulation of the treatment liquid L.

[0079] First, the calculation unit 104 calculates the replenishment amount R of the treatment liquid L to the tank 20 via the supply unit 50 every set time t0 (step S301). The set time t0 is, for example, 1 hour, but it can also be 10 minutes. The set time t0 can be changed appropriately. Hereinafter, the replenishment amount R every set time t0 will also be referred to as the replenishment amount R.

[0080] For example, Figure 5 As shown, if the first determination unit 102 determines that the storage volume H is less than the lower limit Hmin (step S201: "Yes"), the processing liquid L is replenished. The more processing liquid L is consumed in the processing unit 10, the easier it is for the storage volume H to decrease, and the more replenishment R is required. The replenishment amount R is equal to the consumption amount.

[0081] The processing unit 10 consumes processing liquid L when processing the substrate W. Furthermore, during periods when processing of the substrate W is interrupted, the nozzle 16 periodically ejects the processing liquid L to prevent it from stagnating around the nozzle 16 for an extended period. Therefore, the processing unit 10 also consumes processing liquid L during periods when processing of the substrate W is interrupted.

[0082] However, compared to the period during which substrate W is processed, the consumption of processing liquid L and the replenishment amount R are less during the period when substrate W processing is interrupted. Furthermore, the fewer substrates W are processed per set time t0, the less processing liquid L is consumed and the less replenishment amount R is required. The replenishment amount R and the consumption amount vary depending on the operating conditions of the substrate processing apparatus 1.

[0083] The calculation unit 104 calculates the replenishment amount R, for example, based on the measurement value of the flow meter 52 installed on the supply line 51. In this case, the calculation unit 104 calculates the replenishment amount R by integrating the measurement value of the flow meter 52 over a set time t0.

[0084] The calculation unit 104 can also receive a processing plan including the processing timing of the substrate W from the host computer 200, and calculate the replenishment amount R according to the processing plan. The calculation unit 104 calculates the number of substrates W processed per set time t0 according to the processing timing of the substrate W, and calculates the consumption of processing liquid L, thereby calculating the replenishment amount R.

[0085] The host computer 200 is located outside the substrate processing apparatus 1 and sends processing plans to the substrate processing apparatus 1. In addition to including the processing timing of the substrate W, the processing plan may also include the supply time of the processing liquid L to the substrate W and the supply flow rate of the processing liquid L to the substrate W. Furthermore, data pre-stored in the control unit 90 can be read and used regarding the supply time and supply flow rate.

[0086] Next, the second replenishment control unit 105 checks whether the calculated value of the replenishment amount R calculated by the calculation unit 104 is less than the set value R0 (step S302). The set value R0 is set in such a way that the proportion of the leachate E in the processing liquid L is small, thereby making the number of particles adhering to the substrate W below a threshold.

[0087] When the set value R0 increases to a certain extent, even if the set value R0 is increased, the number of particles attached to the substrate W hardly decreases, and the amount of waste treatment liquid L increases unnecessarily. Therefore, the set value R0 is set with consideration of the discharge amount in step S304.

[0088] If the calculated value of the replenishment amount R is greater than or equal to the set value R0 (step S302: "No"), the replenishment amount R and the consumption amount are high, and the proportion of the dissolved substance E in the treatment solution L is low. In this case, the second replenishment control unit 105 terminates the current treatment.

[0089] On the other hand, if the calculated value of the replenishment amount R is less than the set value R0 (step S302: "Yes"), the replenishment amount R and the consumption amount are low, and the proportion of the dissolved substance E in the treatment liquid L is high. In this case, the second replenishment control unit 105 determines the discharge amount to reduce the storage amount H of the tank 20 (step S303). The discharge amount is, for example, an amount equal to the difference between the set value R0 and the calculated value.

[0090] Next, the second replenishment control unit 105 reduces the storage amount H of the tank 20 by means of the discharge unit 40 or the processing unit 10 (step S304). The second replenishment control unit 105 uses the first discharge unit 41 to reduce the storage amount H in a short time, but it may also use the second discharge unit 42 or the processing unit 10.

[0091] Alternatively, if the storage volume H in tank 20 is reduced to less than the lower limit Hmin, the second replenishment control unit 105 disables the control of the first replenishment control unit 103. After the treatment liquid L contaminated by the dissolved substance E is discharged, new treatment liquid L is replenished; therefore, compared to the case where discharge and replenishment are performed simultaneously, the discharge and replenishment volumes can be reduced.

[0092] Next, the second replenishment control unit 105 replenishes new processing liquid L to the tank 20 via the supply unit 50 (step S305). The replenishment amount is, for example, equal to the discharge amount, and equal to the difference between the set value R0 and the calculated value. Through this replenishment, the proportion of the leached substance E in the processing liquid L decreases, and the number of particles adhering to the substrate W decreases.

[0093] Next, refer to Figure 9 To explain Figure 8 An example of the results of the processing. In Figure 9 In the diagram, the horizontal axis represents time, and the vertical axis represents the integral value of the flow rate of the new processed liquid L replenished from the supply unit 50 to the tank 20. The integral value is calculated for each set time t0. The integral value can be calculated using either the flow meter 52 or the processing plan sent from the host computer 200.

[0094] If the replenishment amount R at each set time t0 is less than the set value R0, then implement... Figure 8 The steps S303 to S305 shown are as follows: Figure 9 As indicated by the dashed line, new processing fluid L is replenished from the supply unit 50 to the tank 20. On the other hand, if the replenishment amount R at each set time t0 is greater than or equal to the set value R0, this process is not implemented. Figure 8 The steps S303 to S305 are shown.

[0095] Next, refer to Figure 10 This example illustrates the relationship between the number of particles attached to substrate W, the cycle time, and the replenishment amount R. The cycle time will be discussed later. Figure 11 The elapsed time from step S404, i.e., the elapsed time from the end of the liquid replacement process. Details of the liquid replacement process will be described later.

[0096] like Figure 10 As shown, during the period when the actual value of the replenishment amount R is equal to the set value R0, the longer the circulation time, the more progress is made in filtration, and the number of particles adhering to the substrate W decreases. Subsequently, when the actual value of the replenishment amount R becomes zero, the longer the circulation time, the greater the proportion of the dissolved substance E in the treatment solution L, and the number of particles adhering to the substrate W increases. Therefore, it can be seen that by managing the replenishment amount R to be above the set value R0, the increase in particles caused by the circulation of the treatment solution L can be suppressed.

[0097] Next, refer to Figure 11 Here is an example of the processing by the second fluid replacement control unit 109. When the second fluid replacement control unit 109 receives a fluid replacement command for the processing fluid L in the replacement cycle, it causes... Figure 11 The process begins from S401 onwards. For example, a fluid replacement command is sent from the host computer 200.

[0098] The circulating treatment fluid L is present, for example, in tank 20, circulation line 21, devices 23-26 installed in circulation line 21, branch line 22, devices 27-28 installed in branch line 22, return line 30, and device 31 installed in return line 30. The ratio of the volume of treatment fluid L in tank 20 to the total volume of circulating treatment fluid L is, for example, 30% to 50%, but is not particularly limited.

[0099] By periodically replacing the treatment fluid L, its degradation can be suppressed. Inactive gases such as nitrogen are supplied to the upper space of tank 20, but atmospheric air may intrude into this space. Moisture from the atmosphere gradually dissolves into the treatment fluid L, causing it to degrade. The moisture concentration of the new treatment fluid L is lower than that of the treatment fluid L stored in tank 20, and can practically be zero.

[0100] First, when the second liquid replacement control unit 109 receives a liquid replacement command, it stops pump 23 to halt the circulation of the processing liquid L (step S401). By stopping pump 23, it is possible to prevent pump 23 from running dry during the process of emptying tank 20. The second liquid replacement control unit 109 may also stop heater 25 at the same time as stopping pump 23. By stopping the circulation of processing liquid L, it is possible to prevent a portion of the processing liquid L from being overheated in a concentrated manner.

[0101] In addition, the processing of the second liquid replacement control unit 109 and the processing of the first liquid replacement control unit 108 described later are selectively performed. Alternatively, when the second liquid replacement control unit 109 receives a liquid replacement instruction and an instruction to prohibit the processing of the first liquid replacement control unit 108, it starts the processing after step S401.

[0102] Next, in a state where the pump 23 is stopped, the second liquid replacement control unit 109 reduces the storage amount H of the tank 20 through the discharge unit 40 (step S402). Since the circulation of the processing liquid L has been stopped, the second liquid replacement control unit 109 does not use the second discharge unit 42 and uses the first discharge unit 41 to reduce the storage amount H. As a result, the tank 20 becomes an empty tank.

[0103] Next, the second liquid replacement control unit 109 supplies the processing liquid L to the tank 20 through the supply unit 50 (step S403).

[0104] Finally, the second liquid replacement control unit 109 restarts the pump 23 to resume the circulation of the processing liquid L (step S404). The second liquid replacement control unit 109 may also restart the pump 23 and restart the heater 25.

[0105] In addition, in the present embodiment, the timing of restarting the pump 23 is after step S403, but it may be as long as the storage amount H of the tank 20 exceeds a first threshold H1 described later, or may be in the middle of step S403. The timing of restarting the heater 25 may be after the timing of restarting the pump 23, or may be simultaneous.

[0106] The first threshold H1 is less than the lower limit value Hmin (H1 < Hmin). The first threshold H1 is used for the determination of the second determination unit 106. The second determination unit 106 determines whether the storage amount H of the tank 20 is less than the first threshold H1 during the circulation of the processing liquid L. In this determination, for example, the Figure 1 shown detector 61 is used.

[0107] When the second determination unit 106 determines that the storage amount H is less than the first threshold H1, the forced stop unit 107 stops the pump 23. When an abnormality occurs during the circulation of the processing liquid L and the storage amount H decreases, it is possible to prevent the pump 23 from running dry, thereby preventing the pump 23 from malfunctioning.

[0108] In addition, when the pump 23 is restarted, the number of particles P contained in the processing liquid L increases. The particles P are generated, for example, due to the friction between the components constituting the pump 23. The particles P are also generated due to peeling from the circulation line 21 or the devices 23 to 26 by vibration. In addition, when the heater 25 is restarted, the filter 26 thermally expands and the particles P detach from the filter 26. Therefore, the number of particles P increases immediately after the liquid replacement process.

[0109] On the other hand, differently from the second liquid replacement control unit 109, in the state where the processing liquid L is circulated by the pump 23, the first liquid replacement control unit 108 described later performs the process of reducing the storage amount H of the tank 20 by the discharge unit 40 and the process of supplying the new processing liquid L to the tank 20 by the supply unit 50. Since the pump 23 is not stopped, the pump 23 is not restarted either. In addition, since the pump 23 is not stopped, the heater 25 is not stopped either. Therefore, an increase in the number of particles P immediately after the liquid replacement process can be suppressed.

[0110] Next, a description will be given of an example of the process of the first liquid replacement control unit 108 with reference to Figure 12 When the first liquid replacement control unit 108 receives a liquid replacement instruction, the process after S501 shown in Figure 12 is started. In addition, the process of the first liquid replacement control unit 108 and the process of the second liquid replacement control unit 109 are selectively executed. Alternatively, the first liquid replacement control unit 108 may start the process after step S501 when it receives a liquid replacement instruction and an instruction prohibiting the process of the second liquid replacement control unit 109.

[0111] When the first liquid replacement control unit 108 receives a liquid replacement instruction, in the state where the processing liquid L is circulated by the pump 23, the storage amount H of the tank 20 is reduced by the discharge unit 40 (step S501). Since the first liquid replacement control unit 108 keeps the processing liquid L circulating, the processing liquid L can also be continuously heated by the heater 25.

[0112] Alternatively, when the first liquid replacement control unit 108 receives a liquid replacement instruction, in the state where the processing liquid L is circulated by the pump 23, the storage amount H of the tank 20 is reduced to a second threshold value H2 by the discharge unit 40. The second threshold value H2 is greater than the first threshold value H1 and less than the lower limit value Hmin (H1 < H2 < Hmin). The situation where the storage amount H reaches the second threshold value H2 is detected by the detector 62 shown in Figure 1 . Since the storage amount H is maintained at or above the first threshold value H1, the pump 23 can be prevented from being stopped by the forced stop unit 107.

[0113] Unlike the second fluid replacement control unit 109, the first fluid replacement control unit 108 can also use the second discharge unit 42 to reduce the storage volume H of the tank 20. Since the circulation of the processing fluid L is not stopped, the second discharge unit 42 can be used. Furthermore, compared to using the first discharge unit 41, using the second discharge unit 42 allows the processing fluid L to reliably flow in the circulation line 21.

[0114] Next, the first liquid replacement control unit 108 supplies the processing liquid L to the tank 20 via the supply unit 50 while the processing liquid L is circulated by the pump 23 (step S502). The storage amount H of the processing liquid L stored in the tank 20 is restored to the lower limit value Hmin or above.

[0115] Next, the first liquid replacement control unit 108 checks whether steps S501 and S502 have been performed m times (step S503). m is a natural number of 1 or more, and is preset to be the number of times the ratio of the new processing liquid L to the total volume of the circulating processing liquid L is at least a desired value. m can be appropriately changed. m is preferably a natural number of 2 or more. The ratio of the new processing liquid L is the ratio of the new processing liquid L supplied after the start of step S501.

[0116] If the number of times steps S501 and S502 are performed has not reached m (step S503: "No"), the first fluid replacement control unit 108 performs steps S501 and S502 again. On the other hand, if the number of times steps S501 and S502 are performed has reached m (step S503: "Yes"), the first fluid replacement control unit 108 ends the current process.

[0117] Next, refer to Figure 13 This example illustrates the relationship between the number of fluid replacements and the proportion of new fluid. The proportion of new fluid refers to the ratio of the volume of new treated fluid L to the total volume of treated fluid L in the circulation. The number of fluid replacements is... Figure 11 The number of times steps S401 to S404 are performed, or Figure 12 The number of times steps S501 to S502 are performed. The proportion of new treatment fluid L is the proportion of new treatment fluid L supplied after step S401 or step S501 begins.

[0118] The more frequently the solution is changed, the higher the proportion of new solution. During the process... Figure 12 In this treatment scenario, the circulation of the treatment fluid L is not stopped; the old treatment fluid L is discharged and the new treatment fluid L is supplied, thus mixing the old treatment fluid L with the new treatment fluid L. Therefore, with the processing... Figure 11 Compared to the situation in which it was handled, in the case of Figure 12 Under these conditions, the rate of increase in the proportion of fresh liquid is slow. Figure 12The value of m is preferably a natural number of 2 or more, and more preferably a natural number of 3 or more, so that the proportion of new liquid is sufficiently high.

[0119] Next, refer to Figure 14 This example illustrates the number of particles adhering to substrate W immediately after a liquid replacement. The number of liquid replacements is set to ensure a roughly consistent proportion of new liquid. (As per...) Figure 14 As is known, after conducting Figure 12 In the case of liquid replacement, the circulation of the treatment liquid is not stopped; therefore, it is compatible with... Figure 11 Compared to the case of liquid replacement, the number of particles attached to the substrate W can be suppressed to about 1 / 4.

[0120] Next, refer to Figure 15 The substrate processing apparatus 1 according to the modified example will be described below. The main differences will be explained below. The substrate processing apparatus 1 of this modified example includes: a filter 26, which is provided in the circulation line 21 at a position further downstream than the pump 23; an on / off valve 71, which is provided in the circulation line 21 at a position further downstream than the filter 26; and a processing liquid discharge section 72, which discharges processing liquid L from the middle of the circulation line 21 between the filter 26 and the on / off valve 71.

[0121] The treatment fluid discharge unit 72 includes: a discharge line 73 connected to the circulation line 21 between the filter 26 and the on / off valve 71; and an on / off valve 74 for opening and closing the discharge line 73. When the on / off valve 74 opens the discharge line 73, the discharge line 73 discharges the treatment fluid L from the circulation line 21. On the other hand, when the on / off valve 74 closes the discharge line 73, the discharge line 73 stops discharging the treatment fluid L from the circulation line 21.

[0122] Second fluid replacement control unit 109 (refer to) Figure 3 )exist Figure 11 After stopping pump 23 in step S401, pump 23 is started in step S404. Starting pump 23 requires high driving force. High driving force will generate particulates from filter 26, etc. Particulates will contaminate circulation line 21. Once circulation line 21 is contaminated by particulates, a long time and a large amount of treatment fluid L are required to clean circulation line 21.

[0123] Therefore, when the second liquid replacement control unit 109 starts the pump 23 after stopping it, it performs the process of closing the circulation line 21 through the on / off valve 71 and discharging the processing liquid L from the circulation line 21 through the processing liquid discharge unit 72. This allows particles generated when the pump 23 starts to be discharged to the discharge line 73, thereby suppressing contamination of the circulation line 21. Therefore, the time required for filtration until the substrate W processing restarts can be shortened, thereby reducing the amount of processing liquid L used.

[0124] When, for example, the elapsed time since pump 23 started reaches a set time, the second fluid replacement control unit 109 opens the circulation line 21 via the on / off valve 71 and stops the discharge of the processed fluid L through the processed fluid discharge unit 72, and restarts the circulation of the processed fluid L. Figure 11 (Step S404). Furthermore, the time setting is taken into account the time until the particles generated when pump 23 starts reach the discharge line 73.

[0125] The on / off valve 71 and the treated fluid discharge section 72 are preferably located upstream of the connection point between at least one branch line 22 and the circulation line 21. This suppresses contamination not only of the circulation line 21 but also of the branch lines 22. The on / off valve 71 and the treated fluid discharge section 72 are preferably located upstream of the connection points between all branch lines 22 and the circulation line 21.

[0126] The foregoing describes embodiments of the substrate processing apparatus and substrate processing method disclosed herein, but this disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These, of course, also fall within the technical scope of this disclosure.

[0127] Explanation of reference numerals in the attached figures

[0128] 1: Substrate processing apparatus; 10: Processing unit; 20: Tank; 21: Circulation line; 22: Branch line; 40: Discharge unit; 50: Supply unit; 90: Control unit

Claims

1. A substrate processing apparatus comprising: The system comprises: a tank for storing a processing liquid; a circulation line for removing the processing liquid from the tank and returning it to the tank; a branch line branching off from the circulation line; a processing unit for supplying the processing liquid to a substrate via the front end of the branch line; a discharge unit for reducing the amount of processing liquid stored in the tank; a supply unit for supplying new processing liquid to the tank; and a control unit for controlling the processing unit, the discharge unit, and the supply unit. in, The control unit has: The first determination unit determines whether the storage amount of the treatment liquid in the tank is less than the lower limit value; The first replenishment control unit replenishes the processing liquid to the tank through the supply unit when the first determination unit determines that the storage amount is less than the lower limit value. The calculation unit calculates the amount of processing liquid replenished to the tank via the supply unit at set intervals; and If the calculated value of the replenishment amount obtained by the calculation unit is less than the set value, the second replenishment control unit reduces the storage amount in the tank through the discharge unit and replenishes the treatment liquid to the tank through the supply unit.

2. The substrate processing apparatus according to claim 1, characterized in that, The supply unit includes a supply line connected to the tank and a flow meter for measuring the flow rate of the processed liquid passing through the supply line. The calculation unit calculates the replenishment amount based on the measurement value of the flow meter.

3. The substrate processing apparatus according to claim 2, characterized in that, The computing unit receives a processing plan containing the processing timing of the substrate from an external host computer, and calculates the replenishment amount based on the processing plan and the measurement value of the flow meter.

4. The substrate processing apparatus according to claim 1, characterized in that, The computing unit receives a processing plan containing the processing timing of the substrate from an external host computer, and calculates the supplementary amount based on the processing plan.

5. The substrate processing apparatus according to any one of claims 1 to 4, characterized in that, The second replenishment control unit disables the processing of the first replenishment control unit when the storage amount in the tank is reduced to less than the lower limit value.

6. The substrate processing apparatus according to any one of claims 1 to 4, characterized in that, The second replenishment control unit determines the amount by which the storage amount in the tank should be reduced based on the difference between the calculated value of the replenishment amount and the set value.

7. The substrate processing apparatus according to any one of claims 1 to 4, characterized in that, When the calculated value of the replenishment amount is above the set value, the second replenishment control unit neither reduces the storage amount of the tank through the discharge unit nor replenishes the treatment liquid to the tank through the supply unit.

8. The substrate processing apparatus according to any one of claims 1 to 4, characterized in that, The discharge section includes at least one of a first discharge section and a second discharge section. The first discharge section includes a first discharge line connected to the tank and a first on / off valve for opening and closing the first discharge line. The second discharge section includes a second discharge line connected to the circulation line and a second on / off valve for opening and closing the second discharge line.

9. A substrate processing method of the substrate processing apparatus according to claim 1, comprising circulating a processing liquid from a tank to the tank via a circulation line, and supplying the processing liquid to the substrate through a front end of a branch line branching off from the circulation line. The substrate processing method further includes: Determine whether the storage volume of the treatment liquid in the tank is less than the lower limit value; If it is determined that the storage volume is less than the lower limit, new treatment liquid is added to the tank; Calculate the amount of new treatment fluid to be added to the tank at set intervals; and If the calculated replenishment amount is less than the set value, the storage amount in the tank is reduced, and new treatment liquid is added to the tank.

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