Substrate processing apparatus and substrate processing method

Abstract

The invention relates to a substrate processing apparatus and a substrate processing method. The invention provides a technology for improving separation efficiency. A first position (Q1) and a second position (Q2) are defined in a circulation pipe (62) connected to a recovery tank (60) that stores a mixed fluid containing water and an organic solvent, and the circulation pipe (62) is provided with: a first pipe section (62a) that connects the downstream side of the second position (Q2) and the upstream side of the first position (Q1); a second piping section (62b) that connects the downstream side of the first position (Q1) and the upstream side of the second position (Q2); and a bypass piping section (62c) that connects the downstream side of the first position (Q1) and the upstream side of the second position (Q2) in a path different from that of the second piping section (62b). A dehydrator (621) is provided in the first piping section (62a) or the bypass piping section (62c), and in a state where the mixed fluid is circulating in the first piping section (62a) and the bypass piping section (62c), a pump (622) pressurizes the mixed fluid to a separation pressure higher than a circulation pressure required for circulation, and a heater (623) heats the mixed fluid to a predetermined heating temperature.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing device and a substrate processing method. Background Art

[0002] In substrate processing equipment used in the manufacturing process of semiconductor devices, for example, a substrate is treated with a chemical solution and then washed with a rinse solution. In Patent Document 1, isopropyl alcohol (IPA) is supplied to a substrate washed with a rinse solution (i.e., a substrate covered with a rinse solution (typically water)) to replace the rinse solution on the substrate with IPA. The substrate is then rotated at high speed to blow off the IPA adhering to the substrate, thereby drying the substrate. While the surface tension of the adhering liquid may cause the pattern to collapse when the substrate is rotated at high speed to blow off the adhering liquid, this collapse is prevented by pre-displacing the water adhering to the substrate with IPA, which has a lower surface tension. Furthermore, because IPA is bipolar, it can evenly wet the substrate even if the surface is hydrophobic. Therefore, watermarks are less likely to form on the dried substrate.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-41505 Summary of the Invention

[0006] [Problems to be solved by the invention]

[0007] Patent Document 1 describes the recovery of IPA supplied to a substrate. Since IPA is supplied to a substrate covered in water, the recovered IPA is diluted with water (i.e., the IPA is recovered as a mixed liquid with water). Therefore, in order to reuse the recovered IPA, it is necessary to separate the water from the mixed liquid.

[0008] When separating water from a mixture of an organic solvent such as IPA and water, for example, a separation membrane through which water molecules can pass but organic solvent molecules cannot pass is considered. In order to shorten the time required for water separation, it is required to improve the separation efficiency of the separation membrane.

[0009] Therefore, an object of the present disclosure is to provide a technology capable of improving the separation efficiency using a separation membrane.

[0010] [Technical means to solve the problem]

[0011] The first form is a substrate processing device, comprising: a rinsing liquid supply unit for supplying a rinsing liquid containing water to a substrate; an organic solvent supply unit for supplying an organic solvent to the substrate; a recovery tank for storing a mixed fluid, wherein the mixed fluid comprises the water recovered after being supplied to the substrate and the organic solvent recovered after being supplied to the substrate; a circulation piping connected to the recovery tank; a dehydrator provided in the circulation piping and having a separation membrane that allows the water to pass but does not allow the organic solvent to pass; a pump provided in the circulation piping; and a heater provided in the circulation piping; a first position and a second position are defined in the circulation piping, and the circulation piping comprises: a first piping; a second position; a second position; a second position; a first position; a second ... a pipe portion connecting the downstream side of the second position with the upstream side of the first position; a second piping portion connecting the downstream side of the first position with the upstream side of the second position; and a bypass piping portion connecting the downstream side of the first position with the upstream side of the second position via a path different from that of the second piping portion; the dehydrator is provided in the first piping portion or the bypass piping portion, and when the mixed fluid is circulating in the first piping portion and the bypass piping portion, the pump pressurizes the mixed fluid to a separation pressure higher than a circulation pressure required for circulation, and the heater heats the mixed fluid to a specified heating temperature.

[0012] A second aspect is the substrate processing apparatus according to the first aspect, wherein the recovery tank is provided in the second pipe portion.

[0013] A third aspect is the substrate processing apparatus according to the first or second aspect, wherein the heating temperature is higher than the boiling point of the organic solvent at atmospheric pressure and lower than the boiling point of the organic solvent at the separation pressure.

[0014] The fourth aspect is a substrate processing apparatus according to the third aspect, wherein while the mixed fluid is circulating in the first piping portion and the bypass piping portion, the pump pressurizes the mixed fluid to the separation pressure, and then the heater heats the mixed fluid to the heating temperature.

[0015] The fifth form is a substrate processing device according to the third or fourth form, wherein while the concentrated fluid obtained by separating the water from the mixed fluid is circulating in the first piping portion and the bypass piping portion, the heater stops heating, and after the temperature of the concentrated fluid becomes lower than the boiling point of the organic solvent under atmospheric pressure, the pump stops pressurizing the concentrated fluid.

[0016] A sixth aspect is the substrate processing apparatus according to any one of the first to fifth aspects, further comprising a vacuum pump for reducing the pressure of a space on the side of the dehydrator into which the water having passed through the separation membrane flows.

[0017] The 7th form is a substrate processing device according to any one of the 1st to 6th forms, which comprises: a purification tank, which is connected to the recovery tank via the circulation piping and the liquid supply piping, and stores the concentrated fluid obtained by separating the water from the mixed fluid; and a filter, which is arranged in the piping connected to the purification tank, and captures the removal target substance contained in the concentrated fluid flowing through the piping.

[0018] An eighth aspect is the substrate processing apparatus according to the seventh aspect, wherein the concentrated fluid stored in the purge tank is conveyed to the organic solvent supply unit after passing through the filter, and is supplied to the substrate.

[0019] The 9th form is a substrate processing device according to any one of the 1st to 8th forms, wherein the circulation piping has a plurality of branch portions arranged between a branch position further downstream than the 1st position and a confluence position further upstream than the 2nd position, and the recovery tank is respectively arranged in the plurality of branch portions.

[0020] The 10th form is a substrate processing device according to any one of the 1st to 9th forms, wherein the dehydrator is arranged in a posture so that the hole portion serving as the flow path of the mixed fluid in the separation membrane extends in the vertical direction, and the mixed fluid flowing through the circulation piping flows in from the opening on the vertical lower side of the hole portion.

[0021] An eleventh aspect is the substrate processing apparatus according to any one of the first, second, and sixth to tenth aspects, wherein the heating temperature is equal to or higher than the boiling point of the water under the separation pressure.

[0022] The twelfth form is a substrate processing method, which includes: a rinse liquid supplying step of supplying a rinse liquid containing water to a substrate; an organic solvent supplying step of supplying an organic solvent to the substrate; a storage step of storing a mixed fluid in a recovery tank, the mixed fluid containing the water recovered after being supplied to the substrate and the organic solvent recovered after being supplied to the substrate; a filling step of filling the mixed fluid stored in the recovery tank into a circulation pipe connected to the recovery tank; a circulation step of circulating the mixed fluid in the first pipe portion and the bypass pipe portion of the first pipe portion, the second pipe portion and the bypass pipe portion of the circulation pipe; a pressurizing step of pressurizing the mixed fluid circulating in the first pipe portion and the bypass pipe portion to a separation pressure higher than the circulation pressure required for circulation; A heating process for heating the mixed fluid circulating in the first piping portion and the bypass piping portion to a specified heating temperature; and a separation process for allowing the mixed fluid circulating in the first piping portion and the bypass piping portion to flow into a dehydrator having a separation membrane that allows the water to pass but does not allow the organic solvent to pass, thereby separating the water from the mixed fluid; a first position and a second position are defined in the circulation piping, the first piping portion is a piping portion connecting the downstream side of the second position with the upstream side of the first position, the second piping portion is a piping portion connecting the downstream side of the first position with the upstream side of the second position, and the bypass piping portion is a piping portion connecting the downstream side of the first position with the upstream side of the second position in a different path from that of the second piping portion.

[0023] [Effects of the Invention]

[0024] According to each of the first and twelfth aspects, since the pressurized and heated mixed fluid can be flowed into the dehydrator, water can be efficiently separated from the mixed fluid.

[0025] According to the second aspect, since the recovery tank is provided in the second piping portion, the pressurized and heated mixed fluid does not flow into the recovery tank. Therefore, it is not necessary to provide the recovery tank with pressure resistance that can withstand the separation pressure.

[0026] According to the third aspect, the temperature of the mixed fluid can be sufficiently increased without boiling the organic solvent. Therefore, high separation efficiency can be achieved while ensuring safety.

[0027] According to the fourth aspect, since heating is performed after the boiling point is raised by pressurization, the organic solvent does not boil during heating.

[0028] According to the fifth aspect, the pressurized state is maintained until the concentrated fluid is cooled to a temperature lower than the boiling point of the organic solvent at atmospheric pressure. Therefore, the organic solvent does not boil during the cooling process.

[0029] According to the sixth aspect, separation of water can be promoted by reducing the pressure in the space on the side into which the water having passed through the separation membrane flows in the dehydrator.

[0030] According to the seventh aspect, the removal target substance can be removed from the concentrated fluid obtained by separating water from the mixed fluid, thereby improving the cleanliness of the concentrated fluid.

[0031] According to the eighth aspect, the concentrated fluid obtained by separating water from a mixed fluid containing water supplied to a substrate and recovered and an organic solvent supplied to a substrate and recovered is resupplied to the substrate after its cleanliness is improved. This reduces the amount of organic solvent used and discharged.

[0032] According to the ninth aspect, since a plurality of recovery tanks are provided in the circulation piping, water and organic solvent supplied to the substrate and recovered thereafter can be continuously fed by switching the recovery tanks to which the liquids are sent.

[0033] According to the tenth aspect, the mixed fluid flowing from the circulation pipe into the well flows from bottom to top within the vertically extending well. Therefore, the mixed fluid flowing into the well remains fully within the well and comes into contact with the separation membrane. This further improves separation efficiency.

[0034] According to the eleventh aspect, water contained in the mixed fluid can be allowed to flow into the dehydrator in a vapor state, thereby improving the separation efficiency of the separation membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a plan view schematically showing a configuration example of a substrate processing apparatus.

[0036] Figure 2 It is a side view schematically showing a configuration example of a processing unit.

[0037] Figure 3 It is a diagram schematically showing a configuration example of an organic solvent recovery unit.

[0038] Figure 4 It is a side cross-sectional view schematically showing a configuration example of a dehydrator.

[0039] Figure 5 This is a diagram showing an example of the flow of processing performed by the organic solvent recovery unit.

[0040] Figure 6This is a diagram showing an example of a process flow for separating water from a mixed fluid.

[0041] Figure 7 It is a diagram for explaining step S1.

[0042] Figure 8 It is a diagram for explaining step S201.

[0043] Figure 9 It is a diagram for explaining step S202.

[0044] Figure 10 It is a diagram for explaining step S205.

[0045] Figure 11 It is a diagram for explaining step S207.

[0046] Figure 12 It is a diagram for explaining step S211.

[0047] Figure 13 It is a diagram for explaining step S212.

[0048] Figure 14 It is a diagram for explaining step S3.

[0049] Figure 1 5 is a diagram for explaining step S4.

[0050] Figure 16 It is a diagram schematically showing a configuration example of an organic solvent recovery unit according to a modification.

[0051] Figure 17 It is a diagram schematically showing a configuration example of an organic solvent recovery unit according to a modification. DETAILED DESCRIPTION

[0052] The following describes the embodiments with reference to the accompanying drawings. The components described in these embodiments are for illustrative purposes only and are not intended to limit the scope of this disclosure to these components. The drawings are schematic representations, and for ease of explanation, components may be omitted, dimensions exaggerated or simplified, numbers exaggerated or simplified, or components simplified. Furthermore, the positional relationships of the components shown in the drawings may not necessarily be accurate.

[0053] Unless otherwise specified, expressions indicating relative or absolute positional relationships (e.g., "in a direction," "along a direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) not only strictly indicate such positional relationships but also include relative displacements in terms of angle or distance within a tolerance range or a range that achieves the same degree of functionality. Expressions indicating equality (e.g., "same," "equal," "homogeneous," etc.) not only strictly indicate such quantitative equality but also include differences within a tolerance range or a range that achieves the same degree of functionality. Expressions indicating shape (e.g., "circular," "elliptical," "quadrilateral," "cylindrical," etc.) not only strictly indicate such shapes but also include shapes within a range that achieves the same degree of functionality, such as those with concave-convex corners or chamfers, unless otherwise specified. Expressions such as "equipped with," "including," "having," "containing," and "having" constituent elements are not exclusive expressions that exclude the presence of other constituent elements. The expression "at least one of A, B, and C" includes "only A," "only B," "only C," "any two of A, B, and C," and "all of A, B, and C." When ordinal numbers such as "first" and "second" are used, these are used for convenience to facilitate understanding of the embodiments and are not intended to limit the order that may be generated by these ordinal numbers.

[0054] <1. Substrate processing equipment>

[0055] Reference Figure 1 A substrate processing apparatus 100 according to the embodiment will be described. Figure 1 It is a plan view schematically showing a configuration example of the substrate processing apparatus 100 .

[0056] The substrate processing apparatus 100 is a so-called single-wafer processing apparatus that processes target substrates W one by one. The target substrates W processed by the substrate processing apparatus 100 are, for example, semiconductor substrates. The target substrates W are, for example, disk-shaped.

[0057] The substrate processing apparatus 100 includes a load port 1 , a transfer robot 2 , a main transport robot 3 , a processing unit 4 , an organic solvent recovery unit 5 , and a control unit 6 .

[0058] The load port 1 is an interface for taking and placing substrates W from a carrier C, which is a type of storage container for accommodating multiple substrates W. For example, a plurality of load ports 1 are provided (three in the example). The plurality of load ports 1 are arranged side by side in a row in the horizontal direction, for example. The carrier C can be a type that stores substrates W in a confined space (for example, a FOUPfFront Opening Unified Pod, a front-opening wafer box, a SMIF (Standard Mechanical Interface) wafer box, etc.), or a type that exposes substrates W to the outside atmosphere (for example, an OC (Open Cassette, an open wafer box), etc.).

[0059] The transfer robot 2 is a transport device that transports the substrate W. As an example, the transfer robot 2 is a horizontal multi-joint robot, which includes a pair of hands 21, 21 for holding the substrate W and an arm 22 connected to each hand 21. In addition, the transfer robot 2 includes a drive mechanism (not shown) for rotating each hand 21 and flexing, extending, rotating, and lifting each arm 22. The transfer robot 2 transports the substrate W between the carrier C placed on the load port 1 and the main transport robot 3. That is, the transfer robot 2 enters and exits the carrier C placed on the load port 1, and performs a carry-out action (i.e., an action of taking out the substrate W accommodated in the carrier C using the hand 21) and a carry-in action (i.e., an action of accommodating the substrate W held by the hand 21 into the carrier C). In addition, the transfer robot 2 enters and exits the handover position, and transfers the substrate W to and from the main transport robot 3.

[0060] The main transport robot 3 is a transport device that transports the substrate W. As an example, the main transport robot 3 is a horizontal multi-joint robot, which includes a pair of hands 31, 31 for holding the substrate W and an arm 32 connected to each hand 31. In addition, the main transport robot 3 includes a drive mechanism (not shown) for rotating each hand 31 and flexing, extending, rotating, and lifting each arm 32. The main transport robot 3 transports the substrate W between the transfer robot 2 and each processing unit 4. That is, the main transport robot 3 enters and exits the handover position and transfers the substrate W to and from the transfer robot 2. In addition, the main transport robot 3 enters and exits the processing unit 4 to perform a carry-in action (that is, an action of carrying the substrate W held by the hand 31 into the processing unit 4) and a carry-out action (that is, an action of carrying the substrate W in the processing unit 4 with the hand 31).

[0061] The processing units 4 perform a specified process on the substrate W using a processing liquid (e.g., a chemical solution, a rinse liquid, and an organic solvent). Here, for example, multiple (e.g., three) processing units 4 stacked vertically form a tower, with multiple (four in the example shown) towers arranged to surround the main transfer robot 3. The specific structure of the processing units 4 will be described below.

[0062] The organic solvent recovery unit 5 recovers the organic solvent used for treatment in the treatment units 4 and supplies it back to the treatment units 4. For example, the same number of organic solvent recovery units 5 as the number of towers is provided. Each organic solvent recovery unit 5 corresponds to a tower, recovering the organic solvent used for treatment in each treatment unit 4 contained in the corresponding tower and supplying it back to each treatment unit 4. The specific structure of the organic solvent recovery unit 5 will be described below.

[0063] The control unit 6 controls the operation of each component of the substrate processing apparatus 100 (the load port 1, the transfer robot 2, the main transport robot 3, the processing unit 4, and the organic solvent recovery unit 5). The control unit 6 includes, for example, a conventional computer having circuitry. For example, the control unit 6 includes a CPU (Central Processor Unit) serving as a central processing unit for performing various computations (data processing), a ROM (Read Only Memory) storing basic programs, etc., a RAM (Random Access Memory) serving as a work area for the CPU when performing designated processing (data processing), a storage device (specifically, a non-volatile storage device such as a flash memory or a hard disk drive), and a bus connecting these components. A program specifying the processing to be executed by the control unit 6 can be stored in the storage device or RAM. In this case, for example, by having the CPU execute this program, the control unit 6 controls each component of the substrate processing apparatus 100, allowing the processing specified by the program to be executed in the substrate processing apparatus 100. That is, by executing the program by the CPU, a circuit that performs the processing specified by the program can be implemented in the control unit 6. However, part or all of the control performed by the control unit 6 (part or all of the circuit implemented by the control unit 6) can also be performed by hardware such as a dedicated logic circuit (implemented).

[0064] <2. Processing Unit>

[0065] <2-1. Processing Unit Configuration>

[0066] Reference Figure 2 The configuration of the processing unit 4 will be described. Figure 2 It is a side view schematically showing a configuration example of the processing unit 4 .

[0067] The processing unit 4 performs a predetermined process using a processing liquid (e.g., a chemical solution, a rinse liquid, or an organic solvent) on the substrate W. The processing unit 4 includes, for example, a spin chuck 41 , a cup 42 , and a nozzle 43 . The spin chuck 41 , cup 42 , and nozzle 43 are housed in a processing chamber 44 .

[0068] The rotating chuck 41 rotates the substrate W around an axis (rotation axis) A extending vertically through the center of its main surface while holding the substrate W in a horizontal position (a position in which the thickness direction of the substrate W is along the up-down direction (vertical direction)). Specifically, the rotating chuck 41 includes, for example, a rotating base 411. The rotating base 411 is a disc-shaped component that is arranged in a position in which the thickness direction is along the up-down direction. A plurality of chuck pins 412 are provided on the upper surface of the rotating base 411. The plurality of chuck pins 412 are arranged at equal intervals along a circumference corresponding to the periphery of the substrate W. A linkage mechanism (not shown) is connected to the plurality of chuck pins 412 to move them between a contact position and a release position. The so-called "contact position" is the position where the chuck pins 412 contact the periphery of the substrate W. The "release position" is the position where the chuck pins 412 are separated from the periphery of the substrate W. When each of the multiple chuck pins 412 is in the contact position, the substrate W is held (clamped) in a horizontal position above the spin base 411. When each of the multiple chuck pins 412 is in the release position, the substrate W is released from its grip. The linkage mechanism switches the position of the chuck pins 412 in response to instructions from the control unit 6. Specifically, the timing of holding and releasing the substrate W is controlled by the control unit 6. The spin base 411 is connected to a rotation motor 414 via a shaft 413 coaxial with the rotation axis A. The shaft 413 and the rotation motor 414 are housed in a cover 415. The rotation motor 414 rotates the shaft 413 about the rotation axis A. This causes the spin base 411, and thus the substrate W held thereon, to rotate about the rotation axis A. The rotation motor 414 rotates the spin base 411 in response to instructions from the control unit 6. That is, the rotation speed, the start time of the rotation, the end time of the rotation, and the like of the spin base 411 (and therefore the substrate W) are controlled by the control unit 6 .

[0069] The cup 42 receives the processing liquid discharged from the substrate W being held and rotated by the spin chuck 41. Specifically, the cup 42 includes, for example, a cylindrical guide portion 421 coaxially arranged with the rotation axis A; an inclined portion 422 connected to the upper end of the guide portion 421 and having a diameter that decreases upward; and a liquid receiving portion 423 connected to the lower end of the guide portion 421 and forming an upwardly open annular groove. The liquid receiving portion 423 is provided with a cup-side recovery pipe for recovering the liquid received therein. For example, a cup-side recovery pipe (not shown) for a chemical solution and a cup-side recovery pipe 424 for an organic solvent are provided. Furthermore, a cup-side lifting mechanism 425 is connected to the cup 42 to raise and lower the cup between a lower position and an upper position. The "lower position" refers to a position in which the upper end of the cup 42 (specifically, the upper end of the inclined portion 422) is positioned below the substrate W held by the spin chuck 41. The "upper position" is a position where the upper end of the retainer 42 is positioned above the substrate W held by the spin chuck 41. The retainer lifting mechanism 425 raises and lowers the retainer 42 in response to instructions from the control unit 6. In other words, the position of the retainer 42 is controlled by the control unit 6.

[0070] The nozzle 43 discharges a processing liquid toward the upper surface of the substrate W held by the spin chuck 41. For example, separate nozzles 43 are provided for each type of processing liquid. Specifically, a nozzle 43 discharges a chemical liquid (hereinafter also referred to as a "chemical liquid nozzle 43a"), a nozzle 43 discharges a rinse liquid (hereinafter also referred to as a "rinsing liquid nozzle 43b"), and a nozzle 43 discharges an organic solvent (hereinafter also referred to as an "organic solvent nozzle 43c").

[0071] The chemical nozzle 43a discharges a chemical toward the upper surface of the substrate W held by the spin chuck 41. The chemical nozzle 43a is connected to a chemical supply source 433a via a chemical piping 432a through which a chemical valve 431a is inserted. When the chemical valve 431a is opened, chemical liquid is supplied to the chemical nozzle 43a via the chemical piping 432a, and the chemical liquid is discharged from the chemical nozzle 43a. The chemical valve 431a opens and closes in response to instructions from the control unit 6. In other words, the timing of discharging the chemical from the chemical nozzle 43a is controlled by the control unit 6. The chemical liquid is, for example, hydrofluoric acid. However, the chemical liquid is not limited to hydrofluoric acid and may also include at least one of sulfuric acid, acetic acid, nitric acid, hydrochloric acid, hydrofluoric acid, phosphoric acid, aqueous ammonia, aqueous hydrogen peroxide, an organic acid (e.g., citric acid, oxalic acid), an organic base (e.g., TMAH (tetramethylammonium hydroxide), a surfactant, and a preservative.

[0072] The rinsing liquid nozzle 43b sprays rinsing liquid toward the upper surface of the substrate W held by the spin chuck 41. That is, here, the rinsing liquid nozzle 43b functions as a rinsing liquid supply unit that supplies rinsing liquid to the substrate W. The rinsing liquid nozzle 43b is connected to the rinsing liquid supply source 433b via a rinsing liquid pipe 432b through which a rinsing liquid valve 431b is inserted. When the rinsing liquid valve 431b is opened, rinsing liquid is supplied to the rinsing liquid nozzle 43b via the rinsing liquid pipe 432b, and rinsing liquid is sprayed from the rinsing liquid nozzle 43b. The rinsing liquid valve 431b opens and closes in accordance with instructions from the control unit 6. That is, the timing of spraying the rinsing liquid from the rinsing liquid nozzle 43b is controlled by the control unit 6. Here, the rinsing liquid is assumed to be water, specifically, pure water (deionized water), for example.

[0073] The organic solvent nozzle 43c sprays an organic solvent toward the upper surface of the substrate W held by the spin chuck 41. Specifically, the organic solvent nozzle 43c functions as an organic solvent supply unit for supplying organic solvent to the substrate W. The organic solvent nozzle 43c is connected to the organic solvent recovery unit 5 via an organic solvent pipe 432c through which an organic solvent valve 431c is inserted. When the organic solvent valve 431c is opened, an organic solvent (an organic solvent of sufficiently high purity, specifically, an organic solvent with a purity of 99 wt% or greater) is supplied to the organic solvent nozzle 43c via the organic solvent pipe 432c, and the organic solvent is sprayed from the organic solvent nozzle 43c. The organic solvent valve 431c opens and closes in response to instructions from the control unit 6. Specifically, the timing of spraying the organic solvent from the organic solvent nozzle 43c is controlled by the control unit 6. The organic solvent is, for example, a water-soluble organic solvent. Here, the organic solvent is assumed to be isopropyl alcohol (IPA).

[0074] Furthermore, a nozzle movement mechanism may be connected to at least one of the chemical liquid nozzle 43a, the rinse liquid nozzle 43b, and the organic solvent nozzle 43c to enable movement between a processing position and a retreat position. The "processing position" is the position where the processing liquid ejected from the nozzles 43a, 43b, and 43c is supplied to the substrate W held by the spin chuck 41. The "retreat position" refers to a position where the nozzles 43a, 43b, and 43c are located outside (radially outward) of the periphery of the substrate W held by the spin chuck 41 when viewed from above. In this case, the nozzle movement mechanism moves the nozzles 43a, 43b, and 43c in response to instructions from the control unit 6. In other words, the positions of the nozzles 43a, 43b, and 43c are controlled by the control unit 6.

[0075] <2-2. Operation of the processing unit>

[0076] Continue to refer to Figure 2 An example of the operation of the processing unit 4 will be described.

[0077] The operations performed by the processing unit 4 are performed under the control of the control unit 6. Specifically, the control unit 6 controls the chuck pin 412, the rotary motor 414, the cup lifting mechanism 425, the chemical valve 431a, the rinse liquid valve 431b, the organic solvent valve 431c, and the like, thereby causing a series of operations to be performed in the processing unit 4.

[0078] When the substrate W is carried into the processing chamber 44 by the main transfer robot 3 , the spin chuck 41 holds the substrate W. Then, the spin chuck 41 starts to rotate.

[0079] In this state, the chemical liquid valve 431a is opened. Then, the chemical liquid is sprayed from the chemical liquid nozzle 43a toward the upper surface of the substrate W that is held in rotation by the rotating chuck 41. As a result, the chemical liquid is supplied to the entire upper surface of the substrate W, and the substrate W is processed by the chemical liquid (chemical liquid supply process). For example, when hydrofluoric acid is used as the chemical liquid, foreign matter such as particles is removed from the substrate W by the chemical liquid. During the chemical liquid supply process, the support cup 42 is arranged in an upper position. Therefore, the chemical liquid that flies around the substrate W is caught by the support cup 42. That is, the chemical liquid that flies around the substrate W is caught by the inclined portion 422, guided downward by the guide portion 421, and collected in the liquid receiving portion 423. The chemical liquid caught by the support cup 42 (that is, the chemical liquid collected in the liquid receiving portion 423) is recovered via the support cup side recovery pipe f for the chemical liquid (not shown in the figure).

[0080] At a point in time after a specified time has passed since the start of spraying the chemical liquid, the chemical liquid valve 431a is closed. Thus, the spraying of the chemical liquid from the chemical liquid nozzle 43a stops. Next, the rinsing liquid valve 431b is opened. Thus, the rinsing liquid is sprayed from the rinsing liquid nozzle 43b toward the upper surface of the substrate W that is held in rotation by the rotary chuck 41. As a result, the rinsing liquid is supplied to the entire upper surface of the substrate W, and the chemical liquid attached to the substrate W is rinsed away by the rinsing liquid (rinsing liquid supply process). During the rinsing liquid supply process, the support cup 42 is also arranged in an upper position. Therefore, the chemical liquid and rinsing liquid scattered around the substrate W are caught by the support cup 42. The chemical liquid and rinsing liquid caught by the support cup 42 are recovered via the support cup side recovery pipe (not shown) for the chemical liquid.

[0081] At a point in time after a specified time has passed since the start of spraying the rinsing liquid, the rinsing liquid valve 431b is closed. Thus, the spraying of the rinsing liquid from the rinsing liquid nozzle 43b stops. Next, the organic solvent valve 431c is opened. Thus, IPA is sprayed from the organic solvent nozzle 43c toward the upper surface of the substrate W that is held in rotation by the rotary chuck 41. As a result, IPA is supplied to the entire upper surface of the substrate W, and the rinsing liquid attached to the substrate W is replaced with IPA (organic solvent supply process). During the organic solvent supply process, the support cup 42 is also arranged in an upper position. Therefore, the rinsing liquid and IPA scattered around the substrate W are caught by the support cup 42. The rinsing liquid and IPA caught by the support cup 42 are recovered via the support cup side recovery pipe 424 for the organic solvent.

[0082] At a point in time after a specified time has passed since the start of IPA supply, the organic solvent valve 431c is closed. As a result, the discharge of IPA from the organic solvent nozzle 43c stops. At this stage, the rinsing liquid on the substrate W is completely replaced by IPA, and an IPA liquid film covering the entire upper surface of the substrate W is formed. Next, the rotary chuck 41 starts to rotate at high speed. As a result, the substrate W is rotated at high speed, and the IPA on the substrate W is thrown to the surroundings of the substrate W due to centrifugal force (spin drying process). During the high-speed rotation of the substrate W, the support cup 42 is also arranged in an upper position. Therefore, the IPA scattered to the surroundings of the substrate W is caught by the support cup 42. The IPA caught by the support cup 42 is recovered via the support cup side recovery pipe 424 for the organic solvent.

[0083] After a predetermined time has passed since the spin chuck 41 started rotating at high speed, the spin chuck 41 stops rotating. During this stage, the IPA is removed from the substrate W, and the substrate W is dried. The dried substrate W is then carried out of the processing chamber 44 by the main transfer robot 3 .

[0084] Through the above operations, a series of processes for one substrate W is completed. In the processing unit 4, the above series of operations are repeated to process the substrates W one by one.

[0085] <3. Organic Solvent Recovery Department>

[0086] <3-1. Structure>

[0087] Reference Figure 3 The structure of the organic solvent recovery unit 5 will be described. Figure 3 It is a diagram schematically showing a configuration example of the organic solvent recovery unit 5 .

[0088] The organic solvent recovery unit 5 includes a recovery tank 60, a purge tank 70, and a supply tank 80. As an example, the recovery tank 60 and the purge tank 70 are housed in a first storage box 50a, and the supply tank 80 is housed in a second storage box 50b. In addition, as an example, the first storage box 50a is arranged outside the outer wall 100a of the substrate processing apparatus 100 (for example, under the clean room (underground) where the substrate processing apparatus 100 is installed), and the second storage box 50b is arranged inside the outer wall 100a of the substrate processing apparatus 100 ( Figure 1 ).

[0089] fa) Recovery tank 60

[0090] Recovery tank 60 is connected to cup 42 via recovery pipe 61. Specifically, one end of recovery pipe 61 is connected to recovery tank 60, and the other end is connected to cup 42 (specifically, cup-side recovery pipe 424 connected to cup 42). For example, recovery pipe 61 is connected to cups 42 included in each of multiple processing units 4 belonging to the same tower. Recovery pipe 61 is provided with a recovery valve 611. When recovery valve 611 is opened, the organic solvent (herein, IPA) collected by cup 42 during the organic solvent supply and spin drying processes is directed through recovery pipe 61 and flows into recovery tank 60, where it is stored. However, while IPA (IPA of sufficient purity, specifically, 99 wt% or greater) is recovered during the spin drying process, IPA is recovered mixed with the rinse liquid (herein, water) (i.e., diluted with water) during the organic solvent supply process. Therefore, the recovery tank 60 stores a mixed fluid including water recovered after being supplied to the substrate W in the processing unit 4 and IPA recovered after being supplied to the substrate W in the processing unit 4 .

[0091] A circulation pipe (dehydration circulation pipe) 62 is connected to the recovery tank 60. Specifically, one end and the other end of the dehydration circulation pipe 62 are both connected to the recovery tank 60. The dehydration circulation pipe 62 forms a circulation path for the mixed fluid stored in the recovery tank 60 to circulate so as to flow out of the recovery tank 60 and return to the recovery tank 60.

[0092] The dehydration circulation pipe 62 is provided with a dehydrator (separator) 621. The dehydrator 621 separates water from the mixed fluid flowing into the dehydrator to perform dehydration. The structure of the dehydrator 621 will be described below.

[0093] The dehydration circulation pipe 62 includes a first pipe portion 62a, a second pipe portion 62b, and a bypass pipe portion 62c. That is, in the dehydration circulation pipe 62, a first position Q1 and a second position Q2 are defined. The first pipe portion 62a is a pipe portion that connects the downstream side of the second position Q2 to the upstream side of the first position Q1. The second pipe portion 62b is a pipe portion that connects the downstream side of the first position Q1 to the upstream side of the second position Q2. The bypass pipe portion 62c is a pipe portion that connects the downstream side of the first position Q1 to the upstream side of the second position Q2 by a path different from that of the second pipe portion 62b. Here, for example, a dehydrator 621 is provided in the first pipe portion 62a. That is, the second position Q2 is defined to be on the downstream side of the first position Q1 and on the upstream side of the dehydrator 621. In addition, here, for example, a recovery tank 60 is provided in the second pipe portion 62b. That is, the first position Q1 is set to a position on the downstream side of the dehydrator 621 and on the upstream side of the recovery tank 60, and the second position Q2 is set to a position on the downstream side of the recovery tank 60 and on the upstream side of the dehydrator 621.

[0094] A pump (dehydration side liquid feed pump) 622 and a heater 623 are provided in the dehydration circulation pipe 62. Here, for example, both the dehydration side liquid feed pump 622 and the heater 623 are provided in the first pipe portion 62a. As an example, a heater 623 is provided on the upstream side of the dehydrator 621, and a dehydration side liquid feed pump 622 is provided on the upstream side of the heater 623.

[0095] The dehydration side liquid feed pump 622 transports the mixed fluid in the dehydration circulation pipe 62 at a pressure (circulation pressure) P1 required for circulation. In addition, the dehydration side liquid feed pump 622 pressurizes the mixed fluid to a separation pressure P2 (P1 < P2) higher than the circulation pressure P1. As described below, the higher the separation pressure P2, the higher the separation efficiency of water in the dehydrator 621. In addition, as described below, the higher the separation pressure P2, the higher the heating temperature T2 can be increased. The higher the heating temperature T2, the higher the separation efficiency. Therefore, the separation pressure P2 is preferably set to the highest possible value within the range not exceeding the pressure resistance values of the pipe portion through which the pressurized mixed fluid flows and the machines provided therein.

[0096] The heater 623 heats the mixed fluid to a specified heating temperature T2. Here, the heating temperature T2 is set to be higher than the boiling point (reference boiling point) T1 of the organic solvent (here IPA) under atmospheric pressure and lower than the boiling point (pressurized boiling point) T3 of the organic solvent (here IPA) under the separation pressure P2 (T1 < T2 < T3). As will be described below, the higher the heating temperature T2, the higher the separation efficiency of water in the dehydrator 621. On the other hand, if the temperature of the mixed fluid exceeds the boiling point of IPA, most of the IPA in the mixed fluid will boil, and there is a risk of sharply applying a very high pressure to the piping section through which the mixed fluid flows and the machines provided therein. Therefore, here, by pressurizing the mixed fluid to the separation pressure P2 (that is, the separation pressure P2 specified in advance in consideration of the pressure resistance value of the piping section through which the mixed fluid flows, etc.), the boiling point of IPA is increased to the pressurized boiling point T3 higher than the reference boiling point T1. Thus, even if the mixed fluid is heated to a temperature higher than the reference boiling point T1, as long as this temperature does not exceed the pressurized boiling point T3, the IPA contained in the mixed fluid will not boil. That is, the mixed fluid can be heated to a temperature higher than the reference boiling point T1 without boiling the IPA contained in the mixed fluid. Moreover, the separation efficiency can even be improved. Needless to say, the higher the separation pressure P2, the higher the pressurized boiling point T3, and the higher the heating temperature T2 can be increased.

[0097] In the dehydration circulation pipe 62, switching valves f switching valves) 624a and 624b are provided. The switching valves 624a and 624b are in a state where the fluid circulates in the first pipe section 62a, the second pipe section 62b, and the bypass pipe section 62c (the first circulation state X1) ( Figure 8 ) and the state where the fluid circulates in the first pipe section 62a and the bypass pipe section 62c (the second circulation state X2) ( Figure 9 ) are switched between. Here, for example, the first switching valve 624a is provided near the upstream end (the first position Q1) in the second pipe section 62b, and the second switching valve 624b is provided near the downstream end (the second position Q2) in the second pipe section 62b. When the dehydration side liquid feed pump 622 is operated in a state where both of the pair of switching valves 624a and 624b are open, the fluid circulates in the first pipe section 62a, the second pipe section 62b, and the bypass pipe section 62c. That is, the first circulation state X1 is formed. On the other hand, when the dehydration side liquid feed pump 622 is operated in a state where both of the pair of switching valves 624a and 624b are closed, the fluid circulates in the first pipe section 62a and the bypass pipe section 62c. That is, the second circulation state X2 is formed.

[0098] Here, the dehydration-side liquid feed pump 622 pressurizes the mixed fluid to the separation pressure P2 while the mixed fluid is circulating in the first piping section 62a and the bypass piping section 62c (the second circulation state X2). Similarly, the heater 623 heats the mixed fluid to the heating temperature T2 in the second circulation state X2. Therefore, the pressurized and heated mixed fluid flows through the first piping section 62a and the bypass piping section 62c, and the pressurized and heated mixed fluid does not flow through the second piping section 62b (strictly speaking, the piping section of the second piping section 62b that is downstream of the first switching valve 624a and upstream of the second switching valve 624b).

[0099] Therefore, the first piping section 62a, the bypass piping section 62c, and the equipment installed therein (e.g., the dehydrator 621, the dehydration-side liquid feed pump 622, and the heater 623) are designed to have pressure resistance that can withstand the separation pressure P2 and heat resistance that can withstand the heating temperature T2. However, the second piping section 62bf (strictly speaking, the piping section of the second piping section 62b that is downstream of the first switching valve 624a and upstream of the second switching valve 624b) and the equipment installed therein (e.g., the recovery tank 60) may not have pressure resistance that can withstand the separation pressure P2 and heat resistance that can withstand the heating temperature T2. In other words, the second piping section 62b and the equipment installed therein may have lower pressure resistance and lower heat resistance than the first piping section 62a, the bypass piping section 62c, and the equipment installed therein. For example, the first piping portion 62a and the bypass piping portion 62c are formed of pressure-resistant piping (e.g., metal piping), and the piping portion of the second piping portion 62b downstream of the first switching valve 624a and upstream of the second switching valve 624b is formed of piping that is not pressure-resistant (e.g., resin piping). Furthermore, the recovery tank 60 does not need to be a pressure vessel (pressure tank), and may be formed of, for example, an atmospheric pressure tank.

[0100] A buffer tank 60s for storing a mixed fluid is provided in the dehydration circulation piping 62. The buffer tank 60s is provided in the first piping portion 62a or the bypass piping portion 62c (in the example, the bypass piping portion 62c). As described below, in the second circulation state X2 in which the mixed fluid circulates in the first piping portion 62a and the bypass piping portion 62c, the water contained in the mixed fluid is separated in the dehydrator 621. During this period, an amount of mixed fluid equivalent to the separated water is replenished from the buffer tank 60s into the piping, thereby maintaining the state in which the mixed fluid circulates in the first piping portion 62a and the bypass piping portion 62c. The buffer tank 60s does not need to have the same capacity as the recovery tank 60. That is, the capacity of the buffer tank 60s can be smaller than that of the recovery tank 60. Specifically, the buffer tank 60s only needs to have a capacity sufficient to store at least the minimum amount of mixed fluid required to maintain circulation in a state where water separation is complete from the mixed fluid circulating in the first piping section 62a and the bypass piping section 62c. Specifically, as described below, this is a state where the mixed fluid circulates in the first piping section 62a and the bypass piping section 62c while the vacuum pump 531 is operated for a predetermined period of time, and the concentrated fluid circulates in the first piping section 62a and the bypass piping section 62c. The buffer tank 60s is designed to have pressure resistance sufficient to withstand the separation pressure P2 and heat resistance sufficient to withstand the heating temperature T2. As an example, the buffer tank 60s is formed of a pressure vessel (pressure tank).

[0101] Various sensors are installed in the dehydration circulation piping 62. For example, the following sensors may be installed in the dehydration circulation piping 62: a concentration sensor 625 for measuring the concentration of IPA contained in the mixed fluid circulating in the dehydration circulation piping 62; a pressure sensor 626 for detecting the pressure of the mixed fluid circulating in the dehydration circulation piping 62; a temperature sensor 627 for detecting the temperature of the mixed fluid circulating in the dehydration circulation piping 62; and a flow rate sensor (flow meter) 628 for measuring the flow rate of the mixed fluid circulating in the dehydration circulation piping 62. Each of the sensors 625, 626, 627, and 628 may be installed in the first piping portion 62a or the bypass piping portion 62c. For example, any sensor with pressure resistance sufficient to withstand the separation pressure P2 and heat resistance sufficient to withstand the heating temperature T2 may be used. If such a sensor is difficult to install, it may be installed in the second piping portion 62b. In the example shown, the concentration sensor 625 is provided in the second piping portion 62b, and the pressure sensor 626, temperature sensor 627, and flow rate sensor 628 are provided in the first piping portion 62a. Furthermore, in the example shown, the concentration sensor 625 is provided near the downstream side of the first position Q1, the pressure sensor 626 is provided near the downstream side of the dehydration-side liquid feed pump 622, the temperature sensor 627 is provided near the downstream side of the heater 623, and the flow rate sensor 628 is provided near the upstream side of the dehydration-side liquid feed pump 622.

[0102] fb) Dehydrator 621

[0103] Next, in addition to referring to Figure 3 In addition, refer to Figure 4 The dehydrator 621 will be described. Figure 4 It is a side cross-sectional view schematically showing a configuration example of the dehydrator 621.

[0104] The dehydrator 621 includes a separation membrane 51 and a housing 52 .

[0105] The separation membrane 51 is a membrane that allows water to pass through but does not allow the organic solvent (IPA in this case) to pass through (blocks the passage of the organic solvent). Specifically, the separation membrane 51 is, for example, a zeolite membrane formed of zeolite. Zeolite, for example, has a basic unit of a tetrahedral structure (e.g., containing (SiO4) 4- and (AlO4) 5- The separation membrane 51 comprises a crystalline structure formed by interconnecting the basic units of at least one of the above-mentioned elements. Specifically, the separation membrane 51 comprises, for example, a cylindrical base 511 provided with numerous holes 512 extending therethrough in the axial direction. The holes 512 serve as flow paths for the mixed fluid within the separation membrane 51. In this case, the entire base 511 may be formed of zeolite, or only the inner circumferential surface of each hole 512 may be formed of zeolite.

[0106] The shell 52 is a hollow cylindrical member that accommodates the separation membrane 51. A pair of sealing members 520 are provided between the shell 52 and the separation membrane 51 accommodated therein to seal them. Each sealing member 520 is, for example, annular and is provided at one end side and the other end side in the axial direction of the separation membrane 51. The internal space of the shell 52 is divided by the separation membrane 51 into the internal space of the separation membrane 51 (i.e., the internal space of each hole 512), namely the hole internal space V1, and the external space of the separation membrane 51, namely the separation space V2. In addition, the shell 52 is provided with an inlet 521, a first outlet 522 and a second outlet 523. The inlet 521 is provided on the end surface on one side of the axial direction of the shell 52 and is connected to the hole internal space V1 via an opening of each hole 512. The first outlet 522 is provided on the end surface on the other side of the axial direction of the shell 52 and is connected to the hole internal space V1 via the other opening of each hole 512. The second outflow port 523 is provided on the side surface (peripheral surface) of the casing 52 and communicates with the separation space V2.

[0107] The dehydration circulation pipe 62 is connected to the inlet 521 and the first outlet 522. Meanwhile, the separation pipe 53, equipped with a vacuum pump 531, is connected to the second outlet 523. The mixed fluid flowing through the dehydration circulation pipe 62 flows from the inlet 521 into the dehydrator 621 (specifically, the cavity space V1) and flows through the cavity space V1. In this state, when the vacuum pump 531 installed in the separation pipe 53 is activated, the separation space V2 is depressurized, creating a pressure difference between the cavity space V1 and the separation space V2. The separation membrane 51 separating the cavity space V1 and the separation space V2 is a membrane that is permeable to water but impermeable to IPA. Therefore, when a pressure difference is established between the cavity space V1 and the separation space V2, the water (water molecules) contained in the mixed fluid flowing into the cavity space V1 passes through the separation membrane 51, reaches the separation space V2, and flows into the separation pipe 53 through the second outlet 523. In this way, water is separated from the mixed fluid. Meanwhile, the IPA (IPA molecules) contained in the mixed fluid flowing into the cavity interior space V1 cannot pass through the separation membrane 51 and therefore flows through the cavity interior space V1 and into the dehydration circulation pipe 62 via the first outlet 522. In this way, the mixed fluid flows out of the dehydrator 621 with an increased IPA concentration compared to when it entered the dehydrator 621. Each time the mixed fluid passes through the dehydrator 621, the IPA concentration in the mixed fluid increases.

[0108] Here, the mixed fluid flowing into the dehydrator 621 is pressurized to the separation pressure P2 and heated to the heating temperature T2. When the pressurized mixed fluid flows into the space V1 in the hole, the pressure difference between the space V1 in the hole and the separation space V2 will become larger than when the unpressurized mixed fluid flows in. As a result, the number of water molecules passing through the separation membrane 51 per unit time will increase. In addition, if the mixed fluid is heated, the average kinetic energy of the water molecules contained in the mixed fluid will increase compared to the unheated case. As a result, the number of water molecules passing through the separation membrane 51 per unit time will increase. In this way, the separation efficiency (dehydration efficiency) is improved by pressurizing and heating the mixed fluid flowing into the dehydrator 621.

[0109] In addition, the structure of the separation pipe 53 side into which the water separated from the mixed fluid flows can be appropriately specified. Here, for example, a condenser 532 is provided at a position upstream of the vacuum pump 531 in the separation pipe 53. A drainage pipe 54 is connected to the condenser 532 to guide the condensed water therein. A decomposer 541 is provided in the drainage pipe 54 to decompose the organic solvent (here, IPA) contained in trace amounts in the water flowing therein to improve the purity of the water. The decomposer 541 can also electrolyze the IPA contained in the water to improve the purity of the water. In this case, the decomposer 541 can be composed of, for example, a tank for temporarily storing the water flowing through the drainage pipe 54, a pair of electrodes immersed in the water stored in the tank, and a power supply unit that supplies power to the pair of electrodes to form a potential difference between them. The drainage pipe 54 can be connected to the rinsing liquid supply source 433bf of the processing unit 4, for example. Figure 2 ) or can be connected to a factory water recovery line. For example, if drain pipe 54 is connected to flushing liquid supply source 433b, the water separated from the mixed fluid and flowing into separation pipe 53 is condensed by condenser 532 and flows into drain pipe 54. After its purity is increased by decomposer 541, it is guided to flushing liquid supply source 433b and sprayed from flushing liquid nozzle 43b as flushing liquid. In other words, in this case, the water separated from the mixed fluid is reused as flushing liquid.

[0110] fc) Purification tank 70

[0111] Refer again Figure 3The purification tank 70 is connected to the recovery tank 60 via the first liquid supply pipe 71 and the dehydration circulation pipe 62. That is, one end of the first liquid supply pipe 71 is connected to the purification tank 70, and the other end of the first liquid supply pipe 71 is connected to the dehydration circulation pipe 62. As an example, the other end of the first liquid supply pipe 71 is connected to the first pipe portion 62a of the dehydration circulation pipe 62 (for example, a position in the first pipe portion 62a that is downstream of the heater 623 and upstream of the dehydrator 621). A first liquid supply valve 711 is provided on the first liquid supply pipe 71. In the state where a fluid (hereinafter also referred to as "concentrated fluid") with a sufficiently improved concentration (purity) of IPA (to the extent that it can be supplied to the substrate W) is obtained by separating water from the mixed fluid in the first piping portion 62a and the bypass piping portion 62c, when the first liquid supply valve 711 is opened, the concentrated fluid is guided to the first liquid supply piping 71 and flows into the purification tank 70 and is stored there.

[0112] A circulation pipe (purification circulation pipe) 72 is connected to the purification tank 70. Specifically, one end and the other end of the purification circulation pipe 72 are both connected to the purification tank 70. The purification circulation pipe 72 forms a circulation path for the concentrated fluid stored in the purification tank 70 to circulate, flowing out of the purification tank 70 and returning to the purification tank 70.

[0113] The purification circulation piping 72 is provided with a pump (purification-side liquid delivery pump) 721 and an on-off valve 722. For example, the on-off valve 722 is located downstream of the purification-side liquid delivery pump 721 and upstream of the purification tank 70. The purification-side liquid delivery pump 721 delivers the concentrated fluid within the purification circulation piping 72 at the pressure required for circulation. When the on-off valve 722 is open, the purification-side liquid delivery pump 721 delivers the concentrated fluid at the pressure required for circulation, thereby circulating the concentrated fluid stored in the purification tank 70 within the purification circulation piping 72.

[0114] A filter 723 and a thermostat 724 are provided in the purification circulation piping 72. For example, the filter 723 is located downstream of the purification-side liquid delivery pump 721 and upstream of the purification tank 70, while the thermostat 724 is located downstream of the purification-side liquid delivery pump 721 and upstream of the filter 723. The filter 723 captures removal targets (e.g., particles, metals, etc.) contained in the concentrated fluid flowing through the purification circulation piping 72. As the concentrated fluid passes through the filter 723, the removal targets contained in the concentrated fluid are removed from the concentrated fluid, thereby improving the cleanliness of the concentrated fluid. An exhaust piping 7231 can be connected to the filter 723. The thermostat 724 is a device with cooling and heating capabilities. For example, it is an electronic cooler or heater that uses a Peltier element for electronic cooling and heating. If high-temperature fluid passes through the filter 723, there is a risk that the performance of the filter 723 will be reduced due to thermal expansion, etc. Therefore, here, the temperature regulator 724 cools the concentrated fluid circulating in the purification circulation pipe 72 to a predetermined temperature (for example, room temperature) as needed, thereby suppressing the performance degradation of the filter 723 .

[0115] Various sensors can be installed in the purification circulation piping 72. For example, the following sensors can be installed in the purification circulation piping 72: a pressure sensor 725 for detecting the pressure of the concentrated fluid circulating in the purification circulation piping 72; a temperature sensor 726 for detecting the temperature of the concentrated fluid circulating in the purification circulation piping 72; and a particle counter (not shown) for counting the number of particles contained in the concentrated fluid circulating in the purification circulation piping 72. In the example shown, the pressure sensor 725 is installed near the downstream side of the purification-side liquid delivery pump 721, and the temperature sensor 726 is installed near the downstream side of the thermostat 724.

[0116] (d) Supply tank 80

[0117] The supply tank 80 is connected to the purge tank 70 via a second liquid supply pipe 81 and a purge circulation pipe 72. Specifically, one end of the second liquid supply pipe 81 is connected to the supply tank 80, while the other end is connected to the purge circulation pipe 72. For example, the other end of the second liquid supply pipe 81 is connected to the purge circulation pipe 72 upstream of the filter 723 and downstream of the purge-side liquid supply pump 721. However, the other end of the second liquid supply pipe 81 may be directly connected to the purge tank 70 without passing through the purge circulation pipe 72. A second liquid supply valve 811 is provided on the second liquid supply pipe 81. When a concentrated fluid f with a sufficiently high cleanliness (a level that can be supplied to the substrate W) is obtained in the purification tank 70 (referred to as "purified fluid"), when the second liquid supply valve 811 is opened, the purified fluid is guided to the second liquid supply pipe 81 and flows into the supply tank 80 and is stored there.

[0118] The supply tank 80 can be connected to a fresh liquid supply source 821 via a fresh liquid pipe 82. In this case, one end of the fresh liquid pipe 82 is connected to the supply tank 80, and the other end of the fresh liquid pipe 82 is connected to the fresh liquid supply source 821. The fresh liquid supply source 821 is a source of unused IPA (IPA of sufficiently high purity, specifically, IPA with a purity of 99 wt% or greater, for example) that has never been supplied to the substrate W. A fresh liquid valve 822 is provided on the fresh liquid pipe 82. When the fresh liquid valve 822 is opened, the unused IPA is guided into the fresh liquid pipe 82 and flows into the supply tank 80, where it is stored.

[0119] The supply tank 80 is connected to the organic solvent nozzle 43c via the third liquid supply pipe 83. That is, one end of the third liquid supply pipe 83 is connected to the supply tank 80, and the other end of the third liquid supply pipe 83 is connected to the organic solvent nozzle 43c (specifically, the organic solvent pipe 432c connected to the organic solvent nozzle 43c). Here, for example, the third liquid supply pipe 83 is connected to the organic solvent nozzle 43c of each of the multiple processing units 4 belonging to the same tower. A pump (supply-side liquid supply pump) 831 is provided on the third liquid supply pipe 83. When the organic solvent valve 431c is opened, the purified fluid stored in the supply tank 80 is transported to the organic solvent nozzle 43c side by the supply-side liquid supply pump 831 and is ejected from the organic solvent nozzle 43c.

[0120] The third liquid supply pipe 83 can be equipped with a filter 832 to capture the removal target contained in the purified fluid transported through the third liquid supply pipe 83, and a thermostat 833 to adjust the temperature of the purified fluid transported through the third liquid supply pipe 83 (i.e., to heat or cool the purified fluid to a specified temperature). In the illustrated example, the thermostat 833 is located downstream of the supply-side liquid supply pump 831, and the filter 832 is located downstream of the thermostat 833. Furthermore, various sensors can be installed in the third liquid supply pipe 83. For example, the third liquid supply pipe 83 can be equipped with a pressure sensor 834 to detect the pressure of the purified fluid transported through the third liquid supply pipe 83, and a temperature sensor 835 to detect the temperature of the purified fluid transported through the third liquid supply pipe 83. In the illustrated example, the pressure sensor 834 is located near the downstream side of the supply-side liquid supply pump 831, and the temperature sensor 835 is located near the downstream side of the thermostat 833.

[0121] <3-2. Action>

[0122] Reference Figures 5 to 14 The flow of the treatment performed by the organic solvent recovery unit 5 will be described. Figure 5 1 is a diagram showing an example of the flow of the treatment performed by the organic solvent recovery unit 5 . Figure 6 This is a diagram showing an example of a process flow for separating water from a mixed fluid. Figures 7 to 14 Schematically shows the state of the organic solvent recovery unit 5 in each step. Figures 7 to 14 In the figure, for convenience of explanation, the pipes through which the fluid flows are indicated by solid lines, and the pipes through which the fluid does not flow are indicated by dotted lines.

[0123] The operation of the organic solvent recovery section 5 is performed under the control of the control section 6. Specifically, the control section 6 controls the pumps (dehydration-side liquid feed pump 622, vacuum pump 531, purification-side liquid feed pump 721, and supply-side liquid feed pump 831), valves (recovery valve 611, a pair of switching valves 624a and 624b, first liquid feed valve 711, on-off valve 722, second liquid feed valve 811, and new liquid valve 822), heater 623, condenser 532, decomposer 541, and thermostats 724 and 833) based on input information from sensors (concentration sensor 625, pressure sensors 626, 725, and 834, temperature sensors 627, 726, and 835, and flow rate sensor 628), thereby causing a series of operations to be performed in the organic solvent recovery section 5.

[0124] Step S1

[0125] First, when the recovery tank 60 is empty, the recovery valve 611 is opened. Then, the liquid collected by the holder 42 during the organic solvent supply process and the spin drying process is guided to the recovery pipe 61 and flows into the recovery tank 60. As a result, a mixed fluid (water recovered after being supplied to the substrate W and IPA recovered after being supplied to the substrate W) is stored in the recovery tank 60. Figure 7 (Storage process) When a specified amount of the mixed fluid is stored in the recovery tank 60 , the recovery valve 611 is closed.

[0126] Step S2

[0127] Next, a process is performed to separate water from the mixed fluid stored in the recovery tank 60. Figure 6 and Figures 8 to 13 This processing will be described in detail.

[0128] First, with the pair of switching valves 624a and 624b both open, the dehydration side liquid delivery pump 622 delivers the mixed fluid at a circulation pressure P1. As an example, the circulation pressure P1 is 0.1 MPa or more and 0.2 MPa or less. Thus, the mixed fluid stored in the recovery tank 60 is filled into the first piping portion 62a, the second piping portion 62b, the bypass piping portion 62c, and the buffer tank 60s, and the mixed fluid is circulated in the first piping portion 62a, the second piping portion 62b, and the bypass piping portion 62c (first circulation state X1) (step S201: filling process) ( Figure 8At this time, the mixed fluid flows through the first piping portion 62a and branches at the first position Q1 into a route flowing through the second piping portion 62b (i.e., a route passing through the recovery tank 60) and a route flowing through the bypass piping portion 62c (i.e., a route not passing through the recovery tank 60). The mixed fluids passing through each route merge at the second position Q2 and flow through the first piping portion 62a again.

[0129] Next, while maintaining the circulation pressure P1, the pair of switching valves 624a and 624b are both closed. As a result, the second piping portion 62b is cut off, and the mixed fluid circulates in the first piping portion 62a and the bypass piping portion 62c (second circulation state X2) (step S202: circulation process) Figure 9 At this time, the mixed fluid flowing through the first piping portion 62a flows into the bypass piping portion 62c at the first position Q1 and flows therein, and flows into the first piping portion 62a again at the second position Q2 and flows therein.

[0130] Next, start pressurizing the mixed fluid (step S203: pressurization process). Specifically, the pressure of the dehydration side liquid delivery pump 622 is switched from the circulation pressure P1 to the separation pressure P2. As a result, the mixed fluid circulating in the first piping part 62a and the bypass piping part 62c is pressurized to the separation pressure P2. As an example, the separation pressure P2 is preferably above 0.5 MPa, and particularly preferably above 1.0 MPa. Then, start heating the mixed fluid (step S204: heating process). Specifically, the heater 623 heats the mixed fluid circulating in the first piping part 62a and the bypass piping part 62c to a heating temperature T2. The heating temperature T2 is preferably above 100°C, and particularly preferably above 120°C. As described above, while the mixed fluid is circulating through the first piping portion 62a and the bypass piping portion 62c (second circulation state X2), the dehydration-side liquid feed pump 622 pressurizes the mixed fluid to the separation pressure P2 (i.e., after the boiling point of IPA has been raised to the pressurized boiling point T3), and the heater 623 heats the mixed fluid to the heating temperature T2. Therefore, the IPA does not boil during the heating process.

[0131] Next, while the pressurization and heating of the mixed fluid are continued, the operation of the vacuum pump 531 is started. By operating the vacuum pump 531, the separation space V2 is decompressed, and a pressure difference is set between the inner space V1 of the hole portion and the separation space V2. Due to this pressure difference, the water contained in the mixed fluid flowing into the inner space V1 of the hole portion passes through the separation membrane 51, reaches the separation space V2, and flows into the separation pipe 53. That is, when the mixed fluid circulating in the first piping portion 62a and the bypass piping portion 62c flows into the dehydrator 621 and passes therethrough, the water contained in the mixed fluid is separated (step S205: separation process) ( Figure 10). Here, the mixed fluid flowing into the dehydrator 621 is pressurized to the separation pressure P2 and heated to the heating temperature T2, so that water is efficiently separated from the mixed fluid. In addition, here, the mixed fluid flows into the space V1 in the hole portion in a pressurized state. Therefore, in the state before the vacuum pump 531 is activated (that is, the state in which the vacuum pump 531 is not activated and the pressurized mixed fluid flows into the dehydrator 621), a certain degree of pressure difference is generated between the space V1 in the hole portion and the separation space V2. Therefore, in this state, water separation is also slightly performed. By further activating the vacuum pump 531 from this state, the pressure difference becomes large enough to promote water separation.

[0132] Then, the vacuum pump 531 is operated for a predetermined time. During this period, the mixed fluid is continuously pressurized and heated. During this period, the mixed fluid circulating in the first piping section 62a and the bypass piping section 62c repeatedly passes through the dehydrator 621, thereby increasing the concentration of IPA in the mixed fluid. Furthermore, during this period, an amount of mixed fluid equivalent to the separated water is replenished from the buffer tank 60s into the piping, thereby maintaining the mixed fluid circulating in the first piping section 62a and the bypass piping section 62c. The time required for the IPA concentration in the mixed fluid circulating in the first piping section 62a and the bypass piping section 62c, and in the mixed fluid stored in the buffer tank 60s, to increase sufficiently (to a level suitable for supply to the substrate W) (i.e., the time required to obtain a concentrated fluid) is determined in advance through measurement, calculation, etc., and is set as the predetermined time. Therefore, after a specified time has passed since the start of the operation of the vacuum pump 531, the concentrated fluid circulates through the first piping portion 62a and the bypass piping portion 62c, and the concentrated fluid is stored in the buffer tank 60s. When a specified time has passed since the start of the operation of the vacuum pump 531 (step S206: Yes), the operation of the vacuum pump 531 is stopped. As a result, the separation of water in the dehydrator 621 is basically stopped (step S207). Figure 11 ).

[0133] Next, heating of the concentrated fluid is stopped (step S208). Specifically, heating by the heater 623 is stopped. The process then waits for the concentrated fluid circulating through the first piping section 62a and the bypass piping section 62c to cool below the reference boiling point T1 (82.3°C in the case of IPA) (step S209). When the concentrated fluid temperature falls below the reference boiling point T1 (step S209 returns Yes), pressurization of the concentrated fluid is stopped (step S210). Specifically, the pressure of the dehydration-side liquid feed pump 622 is switched from the separation pressure P2 to the circulation pressure P1. As described above, heating by the heater 623 is stopped while the concentrated fluid is circulating through the first piping section 62a and the bypass piping section 62c. Once the concentrated fluid temperature falls below the reference boiling point T1, the dehydration-side liquid feed pump 622 stops pressurizing the concentrated fluid. In other words, the pressurized state of the concentrated fluid is maintained until the temperature drops below the reference boiling point T1. Therefore, the IPA does not boil during the cooling process.

[0134] Then, the first liquid delivery valve 711 is opened. Then, the concentrated fluid in the first piping portion 62a, the bypass piping portion 62c, and the buffer tank 60s is delivered to the purification tank 70 via the first liquid delivery pipe 71. Thus, the concentrated fluid is stored in the purification tank 70 (step S211) ( Figure 12 ).

[0135] Then, the process of step S201 to step S211 is repeated again. As the number of repetitions increases, the amount of the mixed fluid stored in the recovery tank 60 decreases, and the amount of the concentrated fluid stored in the purification tank 70 increases. When the recovery tank 60 becomes empty (step S212: Yes) Figure 13 ), the process of step S2 (i.e., the process of separating water from the mixed fluid stored in the recovery tank 60) is terminated. Needless to say, when the remaining amount of the mixed fluid in the recovery tank 60 becomes sufficiently small, the recovery tank 60 can be regarded as empty, and the process of step S2 is terminated.

[0136] Step S3

[0137] Next, the cleanliness of the concentrated fluid stored in the purification tank 70 is improved. Specifically, the on-off valve 722 is opened, and the purification side liquid delivery pump 721 delivers the concentrated fluid at a pressure required for circulation. As a result, the concentrated fluid stored in the purification tank 70 is circulated in the purification circulation pipe 72 ( Figure 14). This state lasts for a specified time. During this period, the concentrated fluid circulating in the purification circulation piping 72 repeatedly passes through the filter 723, thereby improving the cleanliness of the concentrated fluid. Here, the time required for the cleanliness of the concentrated fluid circulating in the purification circulation piping 72 to be sufficiently improved (to the extent that it can be supplied to the substrate W) (i.e., the time required to obtain the purified fluid) is determined in advance by measurement, calculation, etc., and is set as the specified time. Therefore, in the stage after the specified time has passed since the start of circulation, the purified fluid is stored in the purification tank 70. After the specified time has passed since the start of circulation, the on-off valve 722 is closed.

[0138] Step S4

[0139] Next, the second liquid delivery valve 811 is opened. Then, the purified fluid in the purification tank 70 is delivered to the supply tank 80 via the second liquid delivery pipe 81. Thus, the purified fluid ( Figure 15 ). For example, when the entire amount of the purge fluid in the purge tank 70 is transferred to the supply tank 80, the second liquid delivery valve 811 is closed. Then, when the organic solvent valve 431c is opened, the purge fluid stored in the supply tank 80 is delivered to the organic solvent nozzle 43c by the supply-side liquid delivery pump 831 and ejected from the organic solvent nozzle 43c. In other words, the purge fluid is supplied to the substrate W. In addition, the purge fluid can pass through the filter 832 on its way through the third liquid delivery pipe 83 to improve its cleanliness, and the temperature can also be adjusted by the thermostat 833 as needed. In addition, if the amount of purge fluid stored in the supply tank 80 becomes less than a specified amount, the new liquid valve 822 can be opened to replenish unused IPA to the supply tank 80.

[0140] This series of processes (steps S1 to S4) is repeated in the organic solvent recovery unit 5. However, the process of the next step S1 may be started before the process of step S4 is completed (for example, when the process of step S3 is completed).

[0141] <4. Effects>

[0142] The substrate processing apparatus 100 of the embodiment includes: a rinsing liquid supply portion (rinsing liquid nozzle) 43b, which supplies a rinsing liquid containing water to the substrate W; an organic solvent supply portion (organic solvent nozzle) 43c, which supplies an organic solvent (for example, IPA) to the substrate W; a recovery tank 60, which stores a mixed fluid, the mixed fluid containing water recovered after being supplied to the substrate W, and an organic solvent recovered after being supplied to the substrate W; a circulation pipe (circulation pipe for dehydration) 62, which is connected to the recovery tank 60; a dehydrator 621, which is arranged on the circulation pipe for dehydration 62 and has a separation membrane 51 that allows water to pass but does not allow the organic solvent to pass; a pump (dehydration side liquid supply pump) 622, which is arranged on the circulation pipe for dehydration 62; and a heater 623, which is arranged on the circulation pipe for dehydration 62. Furthermore, the dehydration circulation piping 62 defines a first position Q1 and a second position Q2. The dehydration circulation piping 62 includes a first piping section 62a connecting the downstream side of the second position Q2 with the upstream side of the first position Q1; a second piping section 62b connecting the downstream side of the first position Q1 with the upstream side of the second position Q2; and a bypass piping section 62c connecting the downstream side of the first position Q1 with the upstream side of the second position Q2 via a different path from the second piping section 62b. A dehydrator 621 is provided in the first piping section 62a or the bypass piping section 62c. While the mixed fluid is circulating in the first piping section 62a or the bypass piping section 62c, a dehydration-side liquid feed pump 622 pressurizes the mixed fluid to a separation pressure P2 higher than the circulation pressure P1 required for circulation, and a heater 623 heats the mixed fluid to a predetermined heating temperature T2.

[0143] This configuration allows the pressurized and heated mixed fluid to flow into the dehydrator 621, effectively separating water from the mixed fluid. Furthermore, this configuration prevents the pressurized and heated mixed fluid from flowing through the second piping section 62b. Therefore, it is not necessary for the second piping section 62b and the equipment located therein to have the same pressure resistance as the first piping section 62a, the bypass piping section 62c, and the equipment located therein (that is, to withstand a separation pressure P2 that is higher than the circulating pressure P1). This improves separation efficiency while miniaturizing the device.

[0144] Furthermore, in the embodiment described above, the recovery tank 60 is disposed within the second piping portion 62b. This configuration prevents the pressurized and heated mixed fluid from flowing into the recovery tank 60. Consequently, the recovery tank 60 does not need to be pressure-resistant enough to withstand the separation pressure P2. Consequently, for example, the recovery tank 60 can be formed from a container other than a pressure vessel (pressure tank), such as an atmospheric pressure tank, enabling the recovery tank 60 to be miniaturized.

[0145] Furthermore, in the embodiment described above, the heating temperature T2 is higher than the boiling point (base boiling point) T1 of the organic solvent (e.g., IPA) at atmospheric pressure and lower than the boiling point (pressurized boiling point) T3 of the organic solvent at the separation pressure P2. This configuration allows the temperature of the mixed fluid to be sufficiently increased without causing the organic solvent to boil. Consequently, high separation efficiency can be achieved while ensuring safety.

[0146] Furthermore, in the embodiment described above, while the mixed fluid is circulating in the first piping portion 62a and the bypass piping portion 62c (second circulation state X2), the dehydration-side liquid feed pump 622 pressurizes the mixed fluid to the separation pressure P2, and then the heater 623 heats the mixed fluid to the heating temperature T2. With this configuration, since heating is performed after the boiling point is raised by pressurization, the organic solvent does not boil during heating.

[0147] Furthermore, in the above embodiment, while the concentrated fluid obtained by separating water from the mixed fluid is circulating through the first piping portion 62a and the bypass piping portion 62c (second circulation state X2), the heater 623 stops heating the concentrated fluid, and after the temperature of the concentrated fluid falls below the boiling point of the organic solvent at atmospheric pressure, the dehydration-side liquid feed pump 622 stops pressurizing the concentrated fluid. This configuration maintains the pressurized state of the concentrated fluid until the temperature drops to a temperature below the boiling point (reference boiling point) T1 of the organic solvent at atmospheric pressure, preventing the organic solvent from boiling during the cooling process.

[0148] The substrate processing apparatus 100 of the embodiment includes a vacuum pump 531 that reduces the pressure in the space (separation space) V2 in the dehydrator 621, into which water flows through the separation membrane 51. This configuration promotes water separation by reducing the pressure in the separation space V2.

[0149] The substrate processing apparatus 100 of the embodiment described above also includes a purge tank 70 connected to the recovery tank 60 via a dehydration circulation pipe 62 and a liquid supply pipe (first liquid supply pipe) 71, storing a concentrated fluid obtained by separating water from a mixed fluid; and a filter 723 provided in a pipe (purification circulation pipe) 72 connected to the purge tank 70, capturing removal target substances contained in the concentrated fluid flowing through the purification circulation pipe 72. This configuration allows the removal target substances to be removed from the concentrated fluid obtained by separating water from the mixed fluid, thereby improving the cleanliness of the concentrated fluid.

[0150] Furthermore, in the above embodiment, the concentrated fluid stored in the purge tank 70 passes through the filter 723 before being transported to the organic solvent nozzle 43c and supplied to the substrate W. Specifically, the concentrated fluid obtained by separating the water from the mixed fluid containing the water recovered after being supplied to the substrate W and the organic solvent recovered after being supplied to the substrate W is resupplied to the substrate W after its cleanliness is improved. This reduces the amount of organic solvent used and discharged (liquid saving). IPA is a volatile organic compound (VOC), and reducing its use and discharge can reduce the environmental impact.

[0151] <5. Variations>

[0152] The configuration and operation of the substrate processing apparatus 100 of the embodiment described above can be modified as appropriate. In the following description, the same elements as those described in the embodiment described above are denoted by the same reference numerals, and their description is omitted.

[0153] <5-1. First Modification>

[0154] Reference Figure 16 The configuration of the organic solvent recovery unit 5 t according to the first modification will be described. Figure 16 It is a diagram schematically showing an example of the organic solvent recovery unit 5t.

[0155] The organic solvent recovery unit 5t includes a plurality of (two in the example shown) recovery tanks 60A and 60B, a plurality of (two in the example shown) purification tanks 70A and 70B, and a supply tank 80 (see FIG. Figure 3 ).

[0156] The recovery tanks 60A and 60B are connected to the support cup 42 via the recovery pipe 61t. That is, one end of the recovery pipe 61t is branched, and the end of one branch part 61A is connected to the first recovery tank 60A, and the end of the other branch part 61B is connected to the second recovery tank 60B. The other end of the recovery pipe 61t is connected to the support cup 42 (specifically, the support cup side recovery pipe 424 connected to the support cup 42). Recovery valves 611A and 611B are provided in each branch part 61A and 61B. When a recovery valve 611A is opened, the liquid collected by the support cup 42 in the organic solvent supply process and the spin drying process is guided to the recovery pipe 61t and flows into the first recovery tank 60A and is stored there. That is, a mixed fluid is stored in the first recovery tank 60A. Similarly, when the other recovery valve 611B is opened, the liquid collected by the cup 42 during the organic solvent supply process and the spin drying process is guided to the recovery pipe 61t and flows into the second recovery tank 60B, where it is stored. In other words, the mixed fluid is stored in the second recovery tank 60B.

[0157] A circulation pipe (dehydration circulation pipe) 62t is connected to the recovery tanks 60A and 60B. A branching position R1 and a confluence position R2 are defined in the dehydration circulation pipe 62t, and a plurality of branch pipes 620A and 620B (the same number as the recovery tanks 60A and 60B) are provided between them. Furthermore, each of the plurality of branch pipes 620A and 620B is provided with a recovery tank 60A and 60B. That is, a first recovery tank 60A is provided in one branch pipe 620A, and a second recovery tank 60B is provided in another branch pipe 620B. Furthermore, a pair of first valves 621A and 621A are provided in one branch pipe 620A across the first recovery tank 60A, and a pair of second valves 621B and 621B are provided in the other branch pipe 620B across the second recovery tank 60B. When the pair of first valves 621A and 621A are opened and the pair of second valves 621B and 621B are closed, a circulation path is formed in which the mixed fluid stored in the first recovery tank 60A circulates so as to flow out of the first recovery tank 60A and return to the first recovery tank 60A. Conversely, when the pair of first valves 621A and 621A are closed and the pair of second valves 621B and 621B are opened, a circulation path is formed in which the mixed fluid stored in the second recovery tank 60B circulates so as to flow out of the second recovery tank 60B and return to the second recovery tank 60B.

[0158] Similar to the aforementioned embodiment, the dehydration circulation piping 62t includes a first piping section 62a, a second piping section 62b, and a bypass piping section 62c. Furthermore, similar to the aforementioned embodiment, the first piping section 62a is provided with a dehydrator 621, a dehydration-side liquid feed pump 622, and a heater 623, while the bypass piping section 62c is provided with a buffer tank 60s. Furthermore, here, for example, multiple recovery tanks 60A and 60B are both provided in the second piping section 62b. In other words, the first position Q1 is located downstream of the dehydrator 621 and upstream of the branching position R1, while the second position Q2 is located downstream of the confluence position R2 and upstream of the dehydrator 621. Furthermore, similar to the aforementioned embodiment, various sensors 625, 626, 627, and 628 may be provided in the dehydration circulation piping 62t.

[0159] Similar to the aforementioned embodiment, switching valves 624a and 624b are provided in the dehydration circulation piping 62t. Switching valves 624a and 624b switch between a state in which the fluid circulates through the first piping section 62a, the second piping section 62b, and the bypass piping section 62c (the first circulation state) and a state in which the fluid circulates through the first piping section 62a and the bypass piping section 62c (the second circulation state). Furthermore, similar to the aforementioned embodiment, the dehydration-side liquid feed pump 622 pressurizes the mixed fluid to the separation pressure P2 while the mixed fluid is circulating through the first piping section 62a and the bypass piping section 62c (the second circulation state). Similarly, the heater 623 heats the mixed fluid to the heating temperature T2 in the second circulation state. Therefore, the first piping section 62a, the bypass piping section 62c, and the equipment installed in these sections (for example, the dehydrator 621, the dehydration-side liquid feed pump 622, the heater 623, and the buffer tank 60s) are provided with pressure resistance that can withstand the separation pressure P2 and heat resistance that can withstand the heating temperature T2. However, the second piping section 62b (strictly speaking, the piping section of the second piping section 62b that is downstream of the first switching valve 624a and upstream of the second switching valve 624b) and the equipment installed therein (for example, the first recovery tank 60A and the second recovery tank 60B) do not need to have pressure resistance that can withstand the separation pressure P2 and heat resistance that can withstand the heating temperature T2. The first recovery tank 60A and the second recovery tank 60B are formed, for example, of atmospheric pressure tanks.

[0160] The purification tanks 70A and 70B are connected to the recovery tanks 60A and 60B via a first liquid supply pipe 71t and a dehydration circulation pipe 62t. Specifically, one end of the first liquid supply pipe 71t branches, with one branch portion 71A connected to the first purification tank 70A and the other branch portion 71B connected to the second purification tank 70B. The other end of the first liquid supply pipe 71t is connected to the first pipe section 62a of the dehydration circulation pipe 62t. First liquid supply valves 711A and 711B are provided in each branch portion 71A and 71B. When concentrated fluid is collected in the first pipe section 62a and the bypass pipe section 62c, opening the first liquid supply valve 711A on the first purification tank 70A side allows the concentrated fluid to flow into the first liquid supply pipe 71t and into the first purification tank 70A, where it is stored. Similarly, when the first liquid supply valve 711B on the second purification tank 70B side is opened while the concentrated fluid is collected in the first piping portion 62a and the bypass piping portion 62c, the concentrated fluid is guided to the first liquid supply pipe 71t and flows into the second purification tank 70B, where it is stored.

[0161] Circulation pipes (purification circulation pipes) 72A and 72B are connected to the first purge tank 70A and the second purge tank 70B, respectively. Similar to the purge circulation pipe 72 in the aforementioned embodiment, each of the purge circulation pipes 72A and 72B is equipped with a purge-side liquid delivery pump 721, an on-off valve 722, a filter 723, a thermostat 724, and various sensors 725 and 726.

[0162] The first purge tank 70A and the second purge tank 70B are connected to the supply tank 80f via the purge circulation pipes 72A and 72B and the second liquid feeding pipe 81t, respectively. Figure 3 ) connection. That is, one end of the second liquid supply pipe 81t branches, with the end of one branch portion 81A connected to the purification circulation pipe 72A on the first purification tank 70A side, and the end of the other branch portion 81B connected to the purification circulation pipe 72B on the second purification tank 70B side. The other end of the second liquid supply pipe 81t is connected to the supply tank 80. Second liquid supply valves 811A and 811B are provided in each branch portion 81A and 81B. When the second liquid supply valve 811A on the first purification tank 70A side is opened after the purified fluid is obtained in the first purification tank 70A, the purified fluid in the first purification tank 70A is guided to the second liquid supply pipe 81t and flows into the supply tank 80, where it is stored. Similarly, when the second liquid supply valve 811B on the second purge tank 70B side is opened while the purge fluid is obtained in the second purge tank 70B, the purge fluid in the second purge tank 70B is guided to the second liquid supply pipe 81t and flows into the supply tank 80 to be stored there.

[0163] In the organic solvent recovery unit 5t, a series of processes similar to those in the above embodiment (steps S1 to S4) are also performed. Figure 5 ).

[0164] That is, similarly to the above-described embodiment, in the organic solvent recovery section 5t, the liquid collected by the cup 42 is first transported to a recovery tank (e.g., the first recovery tank 60A), and the mixed fluid is stored there (step S1). Then, a process of separating water from the mixed fluid stored in the first recovery tank 60A is performed (step S2). However, in the organic solvent recovery section 5t, in parallel with this process, the liquid collected by the cup 42 is transported to another recovery tank (the second recovery tank 60B), and the mixed fluid is stored there. That is, after the liquid collected by the cup 42 is transported to a recovery tank 60A, it is transported to another recovery tank 60B without waiting for the recovery tank 60A to become empty (i.e., without waiting for the process of separating water from the mixed fluid stored in the recovery tank 60A to be completed).

[0165] Similarly to the aforementioned embodiment, in the organic solvent recovery section 5t, the concentrated fluid obtained by separating water from the mixed fluid is transferred to the first purification tank 70A or the second purification tank 70B and stored there. While the concentrated fluid is stored in each of the first purification tank 70A and the second purification tank 70B, the cleanliness of the concentrated fluid is improved (step S3), and the resulting purified fluid is transferred to the supply tank 80f (step S4). Since multiple purification tanks 70A and 70B are provided, the concentrated fluid can be transferred to another purification tank 70B while the cleanliness improvement process is being performed in one purification tank 70A.

[0166] As described above, since the organic solvent recovery unit 5t includes multiple recovery tanks 60A and 60B, the liquid collected by the holder 42 (i.e., water recovered after being supplied to the substrate W, and organic solvent recovered after being supplied to the substrate W) can be continuously transported by switching the recovery tanks 60A and 60B to which the liquid is sent. Furthermore, since the organic solvent recovery unit 5t includes multiple purge tanks 70A and 70B, the concentrated fluid obtained by separating water from the mixed fluid can be continuously transported by switching the purge tanks 70A and 70B to which the liquid is sent. These operations shorten the cycle time from recovering the organic solvent supplied to the substrate W to resupplying it to the substrate W. As a result, the amount of organic solvent used and discharged can be effectively reduced.

[0167] <5-2. Second Modification Example>

[0168] In the organic solvent recovery unit 5 of the embodiment, a gas supply unit 60uf may be provided in the first piping portion 62a or the bypass piping portion 62c. Figure 17 ). Specifically, the gas supply unit 60u may include, for example, the following: a gas supply source 601u that supplies a specified gas (nitrogen, inert gas, air, etc.), a pipe 602u connecting the gas supply source 601u to the first piping portion 62a or the bypass piping portion 62cf (in the figure, the first piping portion 62a), and a valve 603u provided on the pipe 602u. As described above, in the second circulation state X2 in which the mixed fluid circulates in the first piping portion 62a and the bypass piping portion 62c, the water contained in the mixed fluid is separated by the dehydrator 621. Here, during this period, gas is supplied from the gas supply unit 60u to the first piping portion 62a and the bypass piping portion 62c to compensate for the pressure drop in the piping caused by the separation of water. The pressure of the first piping portion 62a and the bypass piping portion 62c is thereby maintained. When the gas supply unit 60u is provided, the buffer tank 60s can be omitted.

[0169] <5-3. Third Variation>

[0170] In the organic solvent recovery section 5 of the embodiment described above, the dehydrator 621 can be positioned and oriented so that the hole 512 extends vertically and the inlet 521 is located vertically below (thus, the first outlet 522 is located vertically above). In this case, the mixed fluid flowing through the dehydration circulation pipe 62 flows into the hole 512 from the vertically below opening.

[0171] According to this variation, the mixed fluid flowing from the dehydration circulation pipe 62 into the well 512 flows from bottom to top through the interior of the well 512 (the well internal space V1) extending in the vertical direction. Therefore, the mixed fluid (especially the liquid IPA and liquid water contained in the mixed fluid) flowing into the well internal space V1 is fully retained in the well internal space V1 by gravity, and is fully in contact with the separation membrane 51. Therefore, the possibility of water contained in the mixed fluid being separated becomes higher. In other words, the separation efficiency is further improved.

[0172] <5-4. Fourth Variation>

[0173] In the organic solvent recovery section 5 of the embodiment, as long as the first piping section 62a, the bypass piping section 62c, and the equipment installed in these sections have the required pressure resistance, sufficient safety can be ensured even if the IPA contained in the mixed fluid boils. In this case, the heating temperature T2 can be above the pressurized boiling point T3. For example, the heating temperature T2 can be above the boiling point of water at the separation pressure P2. When the heating temperature T2 is set above the boiling point of water at the separation pressure P2, the mixed fluid flowing into the dehydrator 621 becomes a vapor state (i.e., both the water and IPA contained in the mixed fluid are in a vapor state). Compared to liquid water, vapor-state water (water vapor) has greater distances between molecules, smaller forces acting on the molecules, and higher average kinetic energy of the molecules, making it easier for it to pass through the separation membrane 51. Therefore, by vaporizing the water contained in the mixed fluid flowing into the dehydrator 621, the separation efficiency is improved. The method of supplying the fluid to be separated to the separation membrane 51 in a vapor state is also known as the VP (vapor permeation) method.

[0174] Even if the heating temperature T2 is lower than the boiling point of water at the separation pressure P2, part of the water contained in the mixed fluid heated to the heating temperature T2 turns into water vapor, and the presence of the water vapor improves the separation efficiency.

[0175] <5-5. Other Variations>

[0176] In the organic solvent recovery unit 5 of the embodiment, the dehydrator 621 is provided in the first piping portion 62a, but the dehydrator 621 may also be provided in the bypass piping portion 62c. In addition, the recovery tank 60 is provided in the second piping portion 62b, but the recovery tank 60 may also be provided in the first piping portion 62a, for example. In this case, the recovery tank 60 is provided with a pressure resistance capable of withstanding the separation pressure P2 and a heat resistance capable of withstanding the heating temperature T2. As an example, the recovery tank 60 in this case is formed by a pressure vessel (pressure tank).

[0177] In the above-described embodiment, the first position Q1 and the second position Q2 can be defined at any position along the dehydration circulation pipe 62 .

[0178] In the organic solvent recovery unit 5 of the embodiment, the mixed fluid that is pressurized and heated does not flow in the separation pipe 53 and the drainage pipe 54. Therefore, the separation pipe 53, the drainage pipe 54 and the machine types (for example, vacuum pump 531, condenser 532 and decomposer 541) arranged on these pipes may not have the pressure resistance that can withstand the separation pressure P2 and the heat resistance that can withstand the heating temperature T2. In other words, the separation pipe 53, the drainage pipe 54 and the machine types arranged on these pipes may have lower pressure resistance and lower heat resistance than the first pipe portion 62a etc. As an example, the separation pipe 53 and the drainage pipe 54 are formed by resin pipes.

[0179] In the organic solvent recovery section 5 of the embodiment described above, a cooler may be provided in the first piping section 62a or the bypass piping section 62c. Alternatively, a thermostat may be provided that functions as a cooler in addition to the heater 623 (i.e., a thermostat having both cooling and heating capabilities). In these cases, for example, after concentrated fluid is obtained in the first piping section 62a and the bypass piping section 62c and heating of the concentrated fluid is stopped (step S208), the concentrated fluid can be cooled by the cooler or thermostat, thereby rapidly lowering the temperature of the concentrated fluid to a temperature below the reference boiling point T1.

[0180] In the organic solvent recovery section 5 of the embodiment, the structure of the dehydrator 621 can be appropriately changed. For example, the separation membrane 51 provided by the dehydrator 621 is not limited to a zeolite membrane. For example, the separation membrane 51 may also be an organic separation membrane. An organic separation membrane is, for example, an organic membrane formed by polyvinyl alcohol, chitosan, polyimide, etc. Alternatively, the separation membrane 51 may also be a CNT (carbon nanotube) separation membrane. A CNT separation membrane is, for example, a membrane obtained by adding carbon nanotubes to a membrane of polyamide, etc. Alternatively, the separation membrane 51 may also be formed by a two-dimensional material. A two-dimensional material is a material composed of one layer of atoms, specifically, molybdenum sulfide (MoS2), a composite atomic layer compound formed by an early transition metal (titanium, vanadium, etc.) and a light element (carbon or nitrogen), etc. Alternatively, the separation membrane 51 may be formed by a MOF (Metal Organic Frameworks) material, or by a carbon material (for example, graphene, graphene oxide, etc.).

[0181] In the substrate processing apparatus 100 of the embodiment described above, the processing units 4 to which the organic solvent recovery unit 5 recovers and supplies the organic solvent are not necessarily the processing units 4 included in the same tower. That is, the organic solvent recovery unit 5 may recover and supply the organic solvent to one or more arbitrarily selected processing units 4. Furthermore, the processing units 4 to which the organic solvent recovery unit 5 recovers the organic solvent may be different from the processing units 4 to which the organic solvent is supplied.

[0182] In the substrate processing apparatus 100 of the embodiment described above, the organic solvent is not limited to IPA. For example, the organic solvent may be at least one of HFE (hydrofluoroether), methanol, ethanol, acetone, and trans-1,2-dichloroethylene. Furthermore, the organic solvent need not be composed of a single component and may be a liquid mixture of multiple components.

[0183] In the substrate processing apparatus 100 of the embodiment, the rinse liquid may be various liquids including water. For example, the rinse liquid may be any one of carbonated water, electrolytic ionized water, hydrogen water, ozone water, and diluted hydrochloric acid water (eg, about 10 to 100 ppm).

[0184] In the substrate processing apparatus 100 of each of the aforementioned embodiments, the substrate W to be processed is not necessarily a semiconductor substrate. For example, the substrate W to be processed may be a glass substrate for a photomask, a glass substrate for a liquid crystal display, a glass substrate for a plasma display, a substrate for an FED (Field Emission Display), a substrate for an optical disk, a magnetic disk, or a substrate for a magneto-optical disk. Furthermore, the substrate W to be processed may not be a completely circular shape and may have shaped portions such as notches or orientation flats.

[0185] As described above, the substrate processing apparatus and substrate processing method have been described in detail. However, all aspects of the description are illustrative only and are not intended to limit the substrate processing apparatus and substrate processing method to these aspects. It should be understood that numerous variations not shown in these examples are conceivable without departing from the scope of the present invention. The various components described in the various embodiments and variations described above may be appropriately combined or omitted as long as they do not conflict with each other.

[0186] [Explanation of Symbols]

[0187] 100: Substrate processing equipment

[0188] 4: Processing unit

[0189] 43c: Organic solvent nozzle

[0190] 43b: Flushing fluid nozzle

[0191] 5: Organic solvent recovery department

[0192] 60: Recovery tank

[0193] 61: Recovery piping

[0194] 62: Circulation piping (circulation piping for dehydration)

[0195] 62a: First piping section

[0196] 62b: Second piping section

[0197] 62c: Bypass piping

[0198] 621: Dehydrator

[0199] 51: Separation membrane

[0200] 622: Pump (dehydration side liquid delivery pump)

[0201] 623: Heater

[0202] 60s: Buffer tank

[0203] 70: Purification Tank

[0204] 71: 1st liquid supply piping

[0205] 72: Purification circulation piping

[0206] 721: Purification side liquid delivery pump

[0207] 723: Filter

[0208] 80: Supply tank

[0209] 81: Second liquid supply piping.

Claims

1. A substrate processing apparatus comprising: a rinsing liquid supply unit for supplying a rinsing liquid containing water to the substrate; an organic solvent supplying unit for supplying an organic solvent to the substrate; a recovery tank storing a mixed fluid, the mixed fluid comprising the water recovered after being supplied to the substrate and the organic solvent recovered after being supplied to the substrate; A circulation pipe connected to the recovery tank; a dehydrator provided in the circulation pipe and comprising a separation membrane that allows the water to pass but does not allow the organic solvent to pass; a pump, disposed in the circulation pipe; and a heater, disposed on the circulation pipe; A first position and a second position are defined in the circulation piping, and the circulation piping includes: a first piping portion connecting a downstream side of the second position with an upstream side of the first position; a second piping portion connecting a downstream side of the first position with an upstream side of the second position; and a bypass piping portion connecting a downstream side of the first position with an upstream side of the second position via a different path from that of the second piping portion; The dehydrator is provided in the first piping portion or the bypass piping portion, and While the mixed fluid is circulating in the first pipe portion and the bypass pipe portion, the pump pressurizes the mixed fluid to a separation pressure higher than a circulation pressure required for circulation, and the heater heats the mixed fluid to a predetermined heating temperature.

2. The substrate processing apparatus according to claim 1, wherein The recovery tank is provided in the second pipe portion.

3. The substrate processing apparatus according to claim 1 or 2, wherein The heating temperature is higher than the boiling point of the organic solvent at atmospheric pressure and lower than the boiling point of the organic solvent at the separation pressure.

4. The substrate processing apparatus according to claim 3, wherein In a state where the mixed fluid is circulating in the first pipe portion and the bypass pipe portion, the pump pressurizes the mixed fluid to the separation pressure, and then the heater heats the mixed fluid to the heating temperature.

5. The substrate processing apparatus according to claim 3, wherein While the concentrated fluid obtained by separating the water from the mixed fluid is circulating in the first piping portion and the bypass piping portion, the heater stops heating, and after the temperature of the concentrated fluid becomes lower than the boiling point of the organic solvent at atmospheric pressure, the pump stops pressurizing the concentrated fluid.

6. The substrate processing apparatus according to claim 1 or 2, wherein A vacuum pump is provided for reducing the pressure of a space on the side of the dehydrator into which the water having passed through the separation membrane flows.

7. The substrate processing apparatus according to claim 1 or 2, comprising: a purification tank connected to the recovery tank via the circulation pipe and the liquid feeding pipe, and storing a concentrated fluid obtained by separating the water from the mixed fluid; and The filter is provided in the pipe connected to the purification tank and captures the removal target substance contained in the concentrated fluid flowing through the pipe.

8. The substrate processing apparatus according to claim 7, wherein The concentrated fluid stored in the purification tank is transported to the organic solvent supply unit after passing through the filter, and is then supplied to the substrate.

9. The substrate processing apparatus according to claim 1 or 2, wherein The circulation pipe includes a plurality of branch portions provided between a branch position downstream of the first position and a merging position upstream of the second position, and The recovery tank is provided in each of the plurality of branch portions.

10. The substrate processing apparatus according to claim 1 or 2, wherein The dehydrator is arranged in a posture such that the hole portion serving as a flow path of the mixed fluid in the separation membrane extends in the vertical direction, and The mixed fluid flowing through the circulation pipe flows in from the vertically lower opening of the hole.

11. The substrate processing apparatus according to claim 1 or 2, wherein The heating temperature is equal to or higher than the boiling point of the water under the separation pressure.

12. A substrate processing method, comprising: a rinsing liquid supplying step of supplying a rinsing liquid containing water to the substrate; an organic solvent supplying step of supplying an organic solvent to the substrate; a storing step of storing a mixed fluid in a recovery tank, the mixed fluid comprising the water recovered after being supplied to the substrate and the organic solvent recovered after being supplied to the substrate; a filling step of filling the mixed fluid stored in the recovery tank into a circulation pipe connected to the recovery tank; a circulation step of circulating the mixed fluid through the first piping portion and the bypass piping portion among the first piping portion, the second piping portion, and the bypass piping portion included in the circulation piping; a pressurizing step of pressurizing the mixed fluid circulating in the first piping portion and the bypass piping portion to a separation pressure higher than a circulation pressure required for the circulation; a heating step of heating the mixed fluid circulating in the first piping portion and the bypass piping portion to a predetermined heating temperature; and a separation step of allowing the mixed fluid circulating in the first piping portion and the bypass piping portion to flow into a dehydrator having a separation membrane that allows the water to pass but does not allow the organic solvent to pass, thereby separating the water from the mixed fluid; A first position and a second position are defined in the circulation piping, the first piping portion is a piping portion connecting the downstream side of the second position with the upstream side of the first position, the second piping portion is a piping portion connecting the downstream side of the first position with the upstream side of the second position, and the bypass piping portion is a piping portion connecting the downstream side of the first position with the upstream side of the second position in a path different from that of the second piping portion.

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