Substrate processing apparatus and substrate processing method

Abstract

To provide a substrate processing apparatus and a substrate processing method that can increase substrate processing efficiency, and reduce environmental impact by reducing a discarded amount of an organic solvent.SOLUTION: A substrate processing apparatus performs substrate-processing of a pattern formed face of a substrate. The apparatus includes: a separation section that collects waste liquid discharged after the substrate-processing and containing an organic solvent and water, and removes at least a part of the water from collected waste liquid; a plurality of separated liquid accumulation sections each of which accumulates separated liquid generated by removing at least a part of the water from the waste liquid by the separation section, for each different concentration of the organic solvent contained in the separated liquid; and a supply section that supplies a process liquid containing at least any of the separated liquids individually accumulated in the plurality of separated liquid accumulation sections, to the pattern formed face of the substrate.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a substrate processing apparatus and a substrate processing method capable of recovering and reusing a processing liquid used for substrate processing.

Background Art

[0002] In the manufacturing processes of semiconductor devices and liquid crystal display devices, processing using a processing liquid is performed on substrates such as semiconductor wafers and glass substrates for liquid crystal display devices. Specifically, a chemical solution is supplied to the main surface of the substrate to perform a chemical solution treatment on the substrate, and then, water such as deionized water (DIW) is supplied to the main surface of the substrate to which the chemical solution has been supplied to perform a rinse treatment for washing away the chemical solution on the substrate. Further, after the rinse treatment, a drying treatment for removing the water remaining on the substrate and drying the substrate is performed.

[0003] Here, in recent years, with the miniaturization of patterns formed on substrates such as semiconductor substrates, the aspect ratio (the ratio of the height to the width of the pattern convex portion) of the convex portions of the pattern having unevenness has been increasing. Therefore, during the drying process, there is a problem of so-called pattern collapse in which the surface tension acting at the interface between the water that has entered the concave portions of the pattern and the gas in contact with the water attracts and collapses adjacent convex portions in the pattern. In response to such a pattern collapse problem, for example, a technique of replacing the water on the substrate with isopropyl alcohol (IPA) and drying the substrate has been proposed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, since the compatibility of water and IPA is low, it takes a certain amount of time to replace the water present on the pattern-formed surface of the substrate with IPA. This results in a problem that the time required for discharging IPA onto the pattern-formed surface of the substrate becomes long, resulting in poor productivity. In addition, if drying is performed in a state where water has not been completely replaced with IPA, there is a problem that collapse of the pattern occurs or increases.

[0006] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a substrate processing apparatus and a substrate processing method that can improve the efficiency of substrate processing and reduce the environmental load by reducing the amount of organic solvent discarded. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the substrate processing apparatus of the present invention is a substrate processing apparatus that processes a pattern formation surface of a substrate, and is characterized in that it comprises a separation unit that recovers waste liquid discharged after the substrate processing and containing an organic solvent and water, and removes at least a portion of the water from the recovered waste liquid, a plurality of separation liquid storage units that independently store separation liquids generated by removing at least a portion of the water from the waste liquid by the separation unit, for each different concentration of the organic solvent contained in the separation liquid, and a supply unit that supplies a processing liquid containing at least any of the separation liquids independently stored in the plurality of separation liquid storage units to the pattern formation surface of the substrate.

[0008] In the above configuration, each of the plurality of separation liquid storage sections is provided with a separation liquid circulation path that draws out the stored separation liquid and returns it to each of the separation liquid storage sections, and it is preferable that a filter is provided midway along the separation liquid circulation path to remove impurities contained in the separation liquid.

[0009] Also, in the above configuration, the separation unit preferably includes a drainage storage unit that stores the recovered drainage, a separation membrane unit that separates and removes at least a part of the water from the drainage derived from the drainage storage unit, a circulation path that supplies the drainage stored in the drainage storage unit to the separation membrane unit and returns the separated liquid generated by the separation membrane unit to the drainage storage unit, and a water discharge pipe that is connected to the separation membrane unit and discharges the water separated by the separation membrane unit.

[0010] Also, in the above configuration, the supply unit preferably includes a multi-way valve that selectively supplies the treatment liquid containing at least any one of the separated liquids respectively supplied from the plurality of separated liquid storage units to the pattern formation surface.

[0011] Furthermore, in the above configuration, the supply unit further includes an organic solvent supply unit that supplies an unused organic solvent and a water supply unit that supplies unused water, and the multi-way valve preferably mixes the organic solvent supplied from the organic solvent supply unit and / or the water supplied from the water supply unit with the separated liquid supplied from at least any one of the plurality of separated liquid storage units to generate the treatment liquid.

[0012] The substrate processing method according to the present invention is a substrate processing method for processing the pattern formation surface of a substrate in order to solve the above problems, and includes a separation step of recovering drainage discharged after the substrate processing and containing an organic solvent and water, and removing at least a part of the water from the recovered drainage; a storage step of independently storing the separated liquid generated by removing at least a part of the water from the drainage in the separation step for each different concentration of the organic solvent contained in the separated liquid; and a supply step of supplying a treatment liquid containing at least any one of the separated liquids independently stored to the pattern formation surface of the substrate.

[0013] In the above configuration, in the storage step, it is preferable to derive the separated liquid being stored, remove impurities contained in the derived separated liquid, and then return and circulate it.

[0014] Also, in the above configuration, the separation step preferably includes a step of storing the recovered drainage liquid, a step of separating and removing at least a part of the water contained in the drainage liquid while circulating the stored drainage liquid, and a step of discharging the water separated from the drainage liquid.

[0015] Furthermore, in the above configuration, the supply step preferably selectively supplies the treatment liquid containing at least any one of the separation liquids to be supplied to the pattern formation surface.

[0016] Also, in the above configuration, the supply step preferably mixes an unused organic solvent and / or unused water with at least any one of the separation liquids respectively stored in the storage step to generate the treatment liquid.

Advantages of the Invention

[0017] According to the present invention, drainage liquid containing an organic solvent and water generated by substrate treatment is recovered, and at least a part of the water is removed from the recovered drainage liquid to generate a separation liquid. Further, this separation liquid is contained in a treatment liquid, and the treatment liquid is used for a new substrate treatment. Here, the separation liquids are separately stored according to the concentration of the organic solvent and then contained in the treatment liquid. Therefore, the treatment liquid can be reused for a new substrate treatment while adjusting the concentration of the organic solvent. For example, a treatment liquid with a low concentration of the organic solvent has better compatibility with water than a treatment liquid with a higher concentration of the organic solvent. Therefore, when removing the water remaining on the pattern formation surface of the substrate, first supply a treatment liquid with a low concentration of the organic solvent, and then sequentially supply treatment liquids with a higher concentration of the organic solvent step by step. Compared with the case of supplying a treatment liquid composed of an organic solvent from the beginning, the water can be replaced with the treatment liquid composed of an organic solvent and removed in a short time. As a result, compared with the prior art, the efficiency of substrate treatment can be improved, the waste liquid of the organic solvent can be reduced by reusing the organic solvent contained in the drainage liquid, and the environmental load can be reduced.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0019] (First Embodiment) The first embodiment of the present invention will be described below with reference to the drawings. However, parts that are not necessary for the description are omitted, and there are parts that are illustrated with magnification or reduction for ease of explanation.

[0020] In this specification, the "substrate" refers to various substrates such as a semiconductor substrate, a glass substrate for a photomask, a glass substrate for a liquid crystal display, a glass substrate for a plasma display, a substrate for a FED (Field Emission Display), a substrate for an optical disk, a substrate for a magnetic disk, and a substrate for a magneto-optical disk. Further, in this specification, the "pattern formation surface" means a surface on which an uneven pattern is formed in an arbitrary region of the substrate, regardless of whether it is planar, curved, or uneven. Also, in this specification, as an example of the substrate, one in which a circuit pattern or the like (hereinafter referred to as "pattern") is formed only on one main surface is used. Here, the pattern formation surface (main surface) on which the pattern is formed is referred to as the "surface".

[0021] [Substrate Processing Apparatus] <Overall Configuration of Substrate Processing Apparatus> The substrate processing apparatus according to this embodiment will be described below with reference to FIG. 1. FIG. 1 is a plan view showing the schematic configuration of the substrate processing apparatus 100 according to this embodiment. The substrate processing apparatus 100 of this embodiment is a single-wafer type substrate processing apparatus used for various substrate processes such as a rinse process using a rinse liquid and a replacement process using a processing liquid after the rinse process.

[0022] As shown in FIG. 1, the substrate processing apparatus 100 includes a substrate processing unit 110 that performs various processes on the substrate W, an indexer unit 120, and a control unit 130 that controls the substrate processing apparatus 100.

[0023] The indexer unit 120 has a function of supplying the substrate W to the substrate processing unit 110 or recovering the substrate W from the substrate processing unit 110. Specifically, the indexer unit 120 includes four container holding units 121, and each container holding unit 121 is provided with one container C. Examples of the container C include a FOUP (Front Opening Unified Pod) that houses a plurality of substrates W in a sealed state, a SMIF (Standard Mechanical Interface) pod, and an OC (Open Cassette). In addition, in this embodiment, the case where there are four container holding units 121 will be described as an example, but the present invention is not limited to this. The number of container holding units 121 may be plural.

[0024] The indexer unit 120 further includes a first transfer unit 122 for transferring the substrate W. The first transfer unit 122 is provided between the container holding unit 121 and the substrate processing unit 110. The first transfer unit 122 includes a base portion 122a fixed to the apparatus housing, a multi-joint arm 122b rotatably provided about a vertical axis with respect to the base portion 122a, and a hand 122c attached to the tip of the multi-joint arm 122b. The hand 122c has a structure capable of placing and holding the substrate W on its upper surface. The first transfer unit 122 can access the container C held by the container holding unit 121 to take out the unprocessed substrate W from the container C or store the processed substrate W in the container C.

[0025] The substrate processing unit 110 performs a rinsing process on the substrate W using a rinsing liquid composed of water, and a replacement process for replacing the rinsing liquid remaining on the surface Wf of the substrate W with a processing liquid containing an organic solvent. The substrate processing unit 110 includes a second transfer unit 111 disposed substantially at the center in a plan view, four substrate processing units 1 disposed so as to surround the second transfer unit 111, and a recovery and reuse unit 2 that recovers and reuses the drainage discharged from the substrate processing unit 1. Details of the substrate processing unit 1 and the recovery and reuse unit 2 will be described later.

[0026] As the second transfer unit 111, for example, a substrate transfer robot can be used. The second transfer unit 111 randomly accesses each substrate processing unit 1 and transfers the substrate W. By including a plurality of substrate processing units 1 and the recovery and reuse unit 2, the substrate processing unit 110 enables parallel processing of a plurality of substrates W.

[0027] The control unit 130 is electrically connected to each part of the substrate processing apparatus 100 and controls the operation of each part. The control unit 130 is configured by a computer having an arithmetic processing unit and a memory. As the arithmetic processing unit, a CPU that performs various arithmetic processes is used. The memory includes a read-only memory ROM that stores a substrate processing program, a random-access memory RAM that stores various information, and a magnetic disk that stores control software, data, and the like. The magnetic disk stores in advance substrate processing condition information (processing recipe) corresponding to the substrate W, control condition information for controlling the substrate processing apparatus 100, and the like. The CPU reads the substrate processing condition information and the control condition information into the RAM and controls each part of the substrate processing apparatus 100 according to the content thereof.

[0028] <Substrate Processing Unit> Next, the configuration of the substrate processing unit 1 in the substrate processing unit 110 will be described below with reference to FIG. 2. FIG. 2 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery and reuse unit 2 in the substrate processing apparatus of the present embodiment. In FIG. 2, for the sake of clarity of the illustrated directional relationship, the XYZ orthogonal coordinate axes are appropriately displayed. In the figure, the XY plane represents a horizontal plane, and the +Z direction represents the vertically upward direction.

[0029] The substrate processing unit 1 includes at least a chamber 11 that is a container for accommodating the substrate W, a substrate holding unit 12 that holds the substrate W, a supply unit 13 that supplies a processing liquid to the substrate W held by the substrate holding unit 12, and a scattering prevention cup 14 that collects a rinse liquid, a processing liquid, etc. that is supplied to the substrate W held by the substrate holding unit 12 and discharged to the outside of the peripheral edge of the substrate W.

[0030] The substrate holding unit 12 includes a rotation drive unit 12a, a spin base 12b, and chuck pins 12c. The spin base 12b has a planar size slightly larger than that of the substrate W. A plurality of chuck pins 12c for gripping the peripheral edge of the substrate W are erected near the peripheral edge of the spin base 12b. The number of installed chuck pins 12c is not particularly limited, but in order to reliably hold the circular substrate W, it is preferably provided with at least 3 or more. In the present embodiment, 3 are arranged at equal intervals along the peripheral edge of the spin base 12b. Each chuck pin 12c includes a substrate support pin that supports the peripheral edge of the substrate W from below, and a substrate holding pin that presses the outer peripheral end surface of the substrate W supported by the substrate support pin to hold the substrate W.

[0031] The spin base 12b is connected to the rotation drive unit 12a. The rotation drive unit 12a rotates around the axis A along the Z direction according to the operation command of the control unit 130. The rotation drive unit 12a is composed of a known belt, motor, and rotation shaft. When the rotation drive unit 12a rotates around the axis A, the substrate W held by the chuck pins 12c above the spin base 12b rotates together with the spin base 12b around a rotation axis parallel to the vertical direction of the surface Wf of the substrate W, that is, around the axis A.

[0032] Next, the supply unit 13 will be described. The supply unit 13 is a unit that supplies a processing liquid for replacing DIW or the like remaining on the pattern formation surface of the substrate W. Examples of the processing liquid include those composed of an organic solvent such as IPA, and a mixed liquid containing an organic solvent and water such as DIW. When the processing liquid is a mixed liquid, the concentration of the organic solvent contained in the mixed liquid is not particularly limited and can be set as appropriate.

[0033] As shown in FIG. 2, the supply unit 13 includes at least a nozzle 13a, a multi-way valve 13b, a supply pipe 13c, an organic solvent supply unit 13d, and a water supply unit 13e.

[0034] The nozzle 13a is connected to the supply pipe 13c to which the processing liquid is supplied, and can discharge the processing liquid onto the surface Wf of the substrate W. The nozzle 13a is attached to the tip of an arm (not shown) extending horizontally. The arm is rotatable under the control of the control unit 130, and the nozzle 13a also moves as the arm rotates. When the nozzle 13a does not discharge the processing liquid, it is disposed at a retracted position outside the peripheral edge of the substrate W and outside the splash prevention cup 14. When discharging the processing liquid, the nozzle 13a is disposed above the spin base 12b, that is, above the central portion (axis A or its vicinity) of the surface Wf of the substrate W, by the rotation of the arm according to the operation command of the control unit 130.

[0035] The multi-way valve 13b can selectively supply a processing liquid containing at least any one of the separation liquids supplied from a plurality of separation liquid storage portions onto the surface Wf of the substrate W (details of the separation liquid storage portions and the separation liquids will be described later). The multi-way valve 13b includes a connection portion 131, a valve 132, a first valve 133, a second valve 134, and a third valve 135.

[0036] Valve 132 is provided in the middle of the path of supply pipe 13c that is pipe-connected to the downstream side of connection part 131. Valve 132 is electrically connected to control unit 130 and is normally closed. The opening and closing of valve 132 are controlled by the operation command of control unit 130. When valve 132 is opened by the operation command of control unit 130, the processing liquid is supplied from nozzle 13a to the surface Wf of substrate W through supply pipe 13c.

[0037] The first valve 133 is provided in the middle of the path of the first separation liquid supply pipe 32e that is pipe-connected to the upstream side of connection part 131. The second valve 134 is provided in the middle of the path of the second separation liquid supply pipe 33e that is pipe-connected to the upstream side of connection part 131. The third valve 135 is provided in the middle of the path of the third separation liquid supply pipe 34e that is pipe-connected to the upstream side of connection part 131. The first valve 133, the second valve 134, and the third valve 135 are each electrically connected to control unit 130 and are normally closed. The opening and closing of these valves are independently controlled by the operation command of control unit 130. Note that the details of the first separation liquid supply pipe 32e, the second separation liquid supply pipe 33e, and the third separation liquid supply pipe 34e will be described later.

[0038] The organic solvent supply unit 13d can supply unused organic solvent to the multi-way valve 13b. The organic solvent supply unit 13d includes a supply pipe 136 and an organic solvent storage unit 138. The organic solvent storage unit 138 is connected to the upstream side of the supply pipe 136, and the connection part 131 is connected to the downstream side. Also, a pump 144, a flow rate adjustment valve 145, and a valve 137 are sequentially provided in the middle of the path of the supply pipe 136 from the upstream side to the downstream side. The organic solvent storage unit 138 stores unused organic solvent. The pump 144 is controlled by the operation command of the control unit 130 and can send the unused organic solvent stored in the organic solvent storage unit 138 to the connection part 131. Also, the flow rate adjustment valve 145 can adjust the flow rate of the unused organic solvent supplied from the organic solvent storage unit 138 by the operation of the pump 144. The valve 137 is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 137 are controlled by the operation command of the control unit 130. When the valve 137 is opened by the operation command of the control unit 130, the unused organic solvent is supplied to the connection part 131 through the supply pipe 136. Note that the unused organic solvent is not particularly limited, and examples include IPA and the like.

[0039] The water supply unit 13e can supply unused water to the multi-way valve 13b. The water supply unit 13e includes a supply pipe 139 and a water storage unit 141. The water storage unit 141 is connected to the upstream side of the supply pipe 139, and the connection part 131 is connected to the downstream side. Also, a pump 146, a flow rate adjustment valve 147, and a valve 140 are sequentially provided in the middle of the path of the supply pipe 139 from the upstream side to the downstream side. The water storage unit 141 stores unused water. The pump 146 is controlled by an operation command of the control unit 130 and can send the unused water stored in the water storage unit 141 to the connection part 131. Also, the flow rate adjustment valve 147 can adjust the flow rate of the unused water supplied from the water storage unit 141 by the operation of the pump 146. The valve 140 is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 140 are controlled by an operation command of the control unit 130. When the valve 140 is opened by an operation command of the control unit 130, the unused organic solvent is supplied to the connection part 131 through the supply pipe 139. Note that the unused water is not particularly limited, and examples include DIW and the like.

[0040] The splash prevention cup 14 is provided so as to surround the spin base 12b. The splash prevention cup 14 is connected to a lifting drive mechanism (not shown) and can be lifted and lowered in the Z direction shown in FIG. 2. When supplying a rinse liquid or a processing liquid to the surface Wf of the substrate W, the splash prevention cup 14 is positioned at a predetermined position as shown in FIG. 2 by the lifting drive mechanism and surrounds the substrate W held by the chuck pin 12c from the side position. Thereby, it is possible to collect liquids such as the rinse liquid and the processing liquid that scatter from the substrate W and the spin base 12b.

[0041] <Recovery and reuse unit> Next, the configuration of the recovery and reuse unit 2 in the substrate processing unit 110 will be described below with reference to FIG. 2.

[0042] The recovery and reuse unit 2 recovers the processing liquid used to remove the water remaining on the surface Wf of the substrate W, separates and removes water from the recovered processing liquid, and makes it reusable. Specifically, as shown in FIG. 2, the recovery and reuse unit 2 includes at least a separation unit 20 and a separated liquid storage unit 30.

[0043] The separation unit 20 can recover the drainage composed of the processing liquid used for substrate processing and remove at least a part of the water from the recovered drainage. Here, the substrate processing means a process including supplying a processing liquid to the surface Wf of the substrate W and replacing the water remaining on the surface Wf of the substrate W with the processing liquid. The separation unit 20 includes at least a recovery pipe 21, an intermediate drainage storage unit 22, a drainage discharge pipe 23, a drainage storage unit 24, a separation membrane unit 25, a circulation path 26, a separated liquid discharge pipe 27, and a water discharge pipe 28.

[0044] The recovery pipe 21 supplies the drainage discharged from the splash prevention cup 14 to the intermediate drainage storage unit 22. One end of the recovery pipe 21 is connected to the splash prevention cup 14, and the other end is connected to the intermediate drainage storage unit 22. A valve 21a is provided in the middle of the path of the recovery pipe 21. The valve 21a is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 21a are controlled by the operation command of the control unit 130. When the valve 21a is opened by the operation command of the control unit 130, the drainage collected by the splash prevention cup 14 is supplied to the intermediate drainage storage unit 22 through the recovery pipe 21.

[0045] The intermediate drainage storage unit 22 is connected to the drainage storage unit 24 via the drainage discharge pipe 23. The intermediate drainage storage unit 22 can temporarily store the recovered drainage. A pump 23b and a valve 23a are sequentially provided in the middle of the path of the drainage discharge pipe 23 from the upstream side to the downstream side. The pump 23b is controlled by the operation command of the control unit 130 and can send the drainage stored in the intermediate drainage storage unit 22 to the drainage storage unit 24. The valve 23a is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 23a are controlled by the operation command of the control unit 130.

[0046] The drainage storage section 24 can store the drainage supplied from the intermediate drainage storage section 22 via the drainage discharge pipe 23. A circulation path 26 is connected to the drainage storage section 24. A separation membrane section 25 is provided in the middle of the circulation path 26. As a result, after discharging the drainage stored in the drainage storage section 24 and supplying it to the separation membrane section 25, at least a part of the water contained in the drainage can be separated by the separation membrane section 25, and the separated liquid obtained can be returned to the drainage storage section 24.

[0047] In addition, a drainage temperature adjustment section 24a is provided in the drainage storage section 24. The drainage temperature adjustment section 24a can adjust the temperature of the drainage stored in the drainage storage section 24. The drainage temperature adjustment section 24a is electrically connected to the control section 130, and adjusts the temperature of the drainage stored in the drainage temperature adjustment section 24a according to an operation command from the control section 130. Thereby, in the separation membrane section 25 described later, for example, when a zeolite membrane is used as the separation membrane, the separation performance of the zeolite membrane can be improved. In this case, as the temperature of the drainage stored in the drainage storage section 24, for example, when separating IPA and water in the waste liquid without vaporizing them, it is preferably in the range of 25°C (RT) to 80°C, more preferably in the range of 50°C to 80°C, and even more preferably in the range of 70°C to 80°C. The drainage temperature adjustment section 24a is not particularly limited, and for example, a known temperature adjustment mechanism such as a Peltier element or a pipe through which temperature-adjusted water passes can be used.

[0048] The separation membrane section 25 can separate and remove at least a part of the water contained in the drainage stored in the drainage storage section 24 from the drainage. Examples of the separation membrane used in the separation membrane section 25 include a dehydration membrane that allows water to permeate and does not allow organic solvents such as IPA to permeate. The separation membrane may be a polymer membrane made of a polymer material, an inorganic membrane made of an inorganic material, or a membrane other than these. Specific examples of the separation membrane include, as described above, a zeolite membrane formed of zeolite.

[0049] As described above, the separation membrane section 25 is provided in the circulation path 26, so that at least a part of the water contained in the drainage can be separated and the separated liquid can be returned to the drainage storage section 24. Further, a pump 26a is provided in the middle of the path of the circulation path 26, on the downstream side of the drainage storage section 24 and on the upstream side of the separation membrane section 25. The pump 26a is controlled by an operation command from the control section 130 and can circulate the drainage stored in the drainage storage section 24 through the circulation path 26. Further, a densitometer 26b for measuring the concentration of an organic solvent such as IPA in the separated liquid is provided on the downstream side of the separation membrane section 25. The value of the concentration of the organic solvent in the separated liquid measured by the densitometer 26b is input to the control section 130.

[0050] One end of the separated liquid discharge pipe 27 is connected to the drainage storage section 24, and the other end is connected to the separated liquid storage section 30. Further, a filter 27a is provided in the middle of the path of the separated liquid discharge pipe 27. The filter 27a can remove solids such as particles and impurities such as metal ions contained in the separated liquid. When removing metal ions, for example, an ion exchange resin or the like can be used as the filter 27a.

[0051] The water discharge pipe 28 is connected to the separation membrane section 25 and discharges the water separated from the drainage (or separated liquid) by the separation membrane section 25.

[0052] The separation liquid storage unit 30 can independently store the separation liquid generated in the separation unit 20 for each concentration of the organic solvent contained in the separation liquid. In the present embodiment, the separation liquid storage unit 30 includes at least a concentration meter 31, a first separation liquid storage unit 32, a second separation liquid storage unit 33, and a third separation liquid storage unit 34. In the first separation liquid storage unit 32, a separation liquid with the lowest concentration of the organic solvent (for example, the concentration of the organic solvent is 25% by mass based on the total mass of the separation liquid. Hereinafter, referred to as the "first separation liquid") is stored. In the third separation liquid storage unit 34, a separation liquid with the highest concentration of the organic solvent (for example, the concentration of the organic solvent is 75% by mass based on the total mass of the separation liquid. Hereinafter, referred to as the "third separation liquid") is stored. In the second separation liquid storage unit 33, a separation liquid with a concentration of the organic solvent higher than that of the first separation liquid and lower than that of the third separation liquid (for example, the concentration of the organic solvent is 50% by mass based on the total mass of the separation liquid. Hereinafter, referred to as the "second separation liquid") is stored.

[0053] The concentration meter 31 can measure the concentration of an organic solvent such as IPA in the separation liquid supplied from the drain liquid storage unit 24. The measured value of the concentration of the organic solvent in the separation liquid measured by the concentration meter 31 is input to the control unit 130.

[0054] The first separation liquid storage unit 32 includes at least a first supply pipe 32a, a first valve 32b, a first separation liquid storage tank 32c, a first separation liquid circulation path 32d, and a first separation liquid supply pipe 32e.

[0055] The first supply pipe 32a branches from the separation liquid discharge pipe 27 on the downstream side of the concentration meter 31 and is connected to the first separation liquid storage tank 32c through a pipeline. A first valve 32b is provided in the middle of the path of the first supply pipe 32a. The first valve 32b is electrically connected to the control unit 130. The opening and closing of the first valve 32b are controlled by an operation command of the control unit 130 based on the measured value of the concentration of the organic solvent measured by the concentration meter 31.

[0056] The first separation liquid storage tank 32c is connected to a first separation liquid circulation path 32d for circulating the first separation liquid stored in the first separation liquid storage tank 32c. Further, along the path of the first separation liquid circulation path 32d, a first pump 32f and a first filter 32g are sequentially provided from the upstream side to the downstream side. The first pump 32f is controlled by an operation command of the control unit 130 and can circulate the first separation liquid stored in the first separation liquid storage tank 32c through the first separation liquid circulation path 32d. The first filter 32g has a function of removing solids such as particles and impurities such as metal ions contained in the first separation liquid. When removing metal ions, as the first filter 32g, for example, an ion exchange resin or the like can be used.

[0057] The first separation liquid supply pipe 32e is connected by a pipeline to the connection part 131 between the first separation liquid storage tank 32c and the multi-way valve 13b. Thereby, the first separation liquid stored in the first separation liquid storage tank 32c can be supplied to the connection part 131 of the multi-way valve 13b. Further, along the path of the first separation liquid supply pipe 32e, a pump 142 and a flow rate adjustment valve 143 are provided from the upstream side to the downstream side. The pump 142 is controlled by an operation command of the control unit 130 and can send out the first separation liquid stored in the first separation liquid storage tank 32c to the connection part 131. Also, the flow rate adjustment valve 143 can adjust the flow rate of the first separation liquid supplied from the first separation liquid storage tank 32c.

[0058] The second separation liquid storage section 33 includes at least a second supply pipe 33a, a second valve 33b, a second separation liquid storage tank 33c, a second separation liquid circulation path 33d, and a second separation liquid supply pipe 33e.

[0059] The second supply pipe 33a branches downstream of the branch point where the first supply pipe 32a branches from the separation liquid discharge pipe 27, and is connected to the second separation liquid storage tank 33c via a pipeline. A second valve 33b is provided in the middle of the path of the second supply pipe 33a. The second valve 33b is electrically connected to the control unit 130. The opening and closing of the second valve 33b is controlled by an operation command of the control unit 130 based on the measured value of the concentration of the organic solvent measured by the concentration meter 31.

[0060] A second separation liquid circulation path 33d for circulating the second separation liquid stored in the second separation liquid storage tank 33c is connected to the second separation liquid storage tank 33c. Further, a second pump 33f and a second filter 33g are sequentially provided in the middle of the path of the second separation liquid circulation path 33d from the upstream side to the downstream side. The second pump 33f is controlled by an operation command of the control unit 130, and can circulate the second separation liquid stored in the second separation liquid storage tank 33c through the second separation liquid circulation path 33d. The second filter 33g has a function of removing solids such as particles and impurities such as metal ions contained in the second separation liquid. When removing metal ions, for example, an ion exchange resin or the like can be used as the second filter 33g.

[0061] The second separation liquid supply pipe 33e is connected to the second separation liquid storage tank 33c and the connection portion 131 of the multi-way valve 13b via a pipeline. Thereby, the second separation liquid stored in the second separation liquid storage tank 33c can be supplied to the connection portion 131 of the multi-way valve 13b. Further, a pump 142 and a flow rate adjustment valve 143 are provided in the middle of the path of the second separation liquid supply pipe 33e from the upstream side to the downstream side. By operating the pump 142, the second separation liquid stored in the second separation liquid storage tank 33c can be supplied to the connection portion 131. Also, the flow rate adjustment valve 143 can adjust the flow rate of the second separation liquid supplied from the second separation liquid storage tank 33c.

[0062] The third separation liquid storage unit 34 includes at least a third supply pipe 34a, a third valve 34b, a third separation liquid storage tank 34c, a third separation liquid circulation path 34d, and a third separation liquid supply pipe 34e.

[0063] The third supply pipe 34a is connected on the downstream side of the branch point where the second supply pipe 33a branches from the separation liquid discharge pipe 27, and is connected to the third separation liquid storage tank 34c through a pipeline. A third valve 34b is provided in the middle of the path of the third supply pipe 34a. The third valve 34b is electrically connected to the control unit 130. The opening and closing of the third valve 34b is controlled by an operation command of the control unit 130 based on the measured value of the concentration of the organic solvent measured by the concentration meter 31.

[0064] A third separation liquid circulation path 34d for circulating the third separation liquid stored in the third separation liquid storage tank 34c is connected to the third separation liquid storage tank 34c. Further, a third pump 34f and a third filter 34g are sequentially provided in the middle of the path of the third separation liquid circulation path 34d from the upstream side to the downstream side. The third pump 34f is controlled by an operation command of the control unit 130, and can circulate the third separation liquid stored in the third separation liquid storage tank 34c through the third separation liquid circulation path 34d. The third filter 34g has a function of removing solids such as particles and impurities such as metal ions contained in the third separation liquid. When removing metal ions, as the third filter 34g, for example, an ion exchange resin or the like can be used.

[0065] The third separation liquid supply pipe 34e is connected by piping to the connection part 131 between the third separation liquid storage tank 34c and the multi-way valve 13b. Thereby, the third separation liquid stored in the third separation liquid storage tank 34c can be supplied to the connection part 131 of the multi-way valve 13b. Also, a pump 142 and a flow rate adjustment valve 143 are provided in the middle of the path of the third separation liquid supply pipe 34e, from the upstream side toward the downstream side. By operating the pump 142, the third separation liquid stored in the third separation liquid storage tank 34c can be supplied to the connection part 131. Also, the flow rate adjustment valve 143 can adjust the flow rate of the third separation liquid supplied from the third separation liquid storage tank 34c.

[0066] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus 100 of the present embodiment will be described below. The substrate processing method according to the present embodiment is used, for example, to recover a processing liquid containing an organic solvent used to remove a rinse liquid composed of water such as DIW remaining on the surface Wf of the substrate W, and to separate and remove water from the recovered processing liquid for reuse. Thereby, in the present embodiment, the amount of organic solvent to be discarded is reduced, enabling a reduction in the environmental load. More specifically, in the recovery and reuse of the processing liquid after substrate processing, the substrate processing method of the present embodiment includes a drainage step of draining the processing liquid after substrate processing, a separation step of recovering the drainage and removing at least a part of the water from the drainage, a storage step of independently storing the separation liquid composed of the drainage from which at least a part of the water has been removed in the separation step, for each different concentration of the organic solvent contained in the separation liquid, and a supply step of supplying a processing liquid containing at least any one of the separation liquids independently stored in the storage step to the surface Wf of the substrate W.

[0067] The drainage step is a step of discharging the processing liquid used for substrate processing on the surface Wf of the substrate W from the substrate processing unit 1. When the valve 21a is opened by an operation command from the control unit 130, the processing liquid collected by the splash prevention cup 14 is discharged as drainage through the recovery pipe 21 connected to the splash prevention cup 14. The drainage discharged through the recovery pipe 21 is stored in the intermediate drainage storage unit 22.

[0068] The separation process is a process of separating and removing at least a part of water from the drained liquid stored in the recovered intermediate drained liquid storage section 22 to generate a separated liquid. When the valve 23a is opened according to the operation command of the control unit 130, the drained liquid stored in the intermediate drained liquid storage section 22 is supplied to the drained liquid storage section 24 through the drained liquid discharge pipe 23 by the operation of the pump 23b. When a predetermined amount of drained liquid is stored in the drained liquid storage section 24, the control unit 130 issues an operation command to close the valve 23a.

[0069] The drained liquid stored in the drained liquid storage section 24 is heated to a predetermined temperature by the drained liquid temperature adjustment section 24a according to the operation command of the control unit 130. Further, the drained liquid stored in the drained liquid storage section 24 is led out by the operation of the pump 26a and circulates through the circulation path 26. The drained liquid flowing through the circulation path 26 is separated and removed of at least a part of the water contained in the drained liquid in the separation membrane section 25 provided in the middle of the path of the circulation path 26. Since the drained liquid is heated by the drained liquid temperature adjustment section 24a, for example, when a zeolite membrane is used in the separation membrane section 25, the separation performance can be improved. The drained liquid from which at least a part of the water has been removed in the separation membrane section 25 is discharged as a separated liquid. Also, the water separated in the separation membrane section 25 is discharged from the water discharge pipe 28. The concentration of the organic solvent contained in the separated liquid is measured by the concentration meter 26b for the separated liquid discharged from the separation membrane section 25. When the measured value of the concentration of the organic solvent is input to the control unit 130 and it is determined that the measured value has not reached a predetermined value, the circulation of the separated liquid in the circulation path 26 continues until the measured value of the concentration of the organic solvent by the concentration meter 26b reaches the predetermined value. As a result, the drained liquid storage section 24 stores the separated liquid in which the concentration of the organic solvent has reached the predetermined value. Also, when it is determined that the measured value of the concentration of the organic solvent in the separated liquid has reached the predetermined value in the concentration meter 26b, the separated liquid is discharged from the separated liquid discharge pipe 27.

[0070] Here, a filter 27a is provided in the middle of the path of the separation liquid discharge pipe 27 for discharging the separation liquid from the drainage storage section 24. Therefore, in this step, for the separation liquid in which the concentration of the organic solvent has reached a predetermined value, the filter 27a can further separate and remove impurities such as particles and metal ions. During the separation step, it is preferable that the first valve 32b of the first separation liquid storage section 32, the second valve 33b of the second separation liquid storage section 33, and the third valve 34b of the third separation liquid storage section 34 are closed by the operation command of the control unit 130.

[0071] The storage step is a step of storing the separation liquid generated in the separation step independently for each concentration of the organic solvent. This step is performed after the separation liquid in which the concentration of the organic solvent has reached a predetermined value is stored in the drainage storage section 24. In this step, first, the concentration of the organic solvent is measured by the concentration meter 31 for the separation liquid flowing through the separation liquid discharge pipe 27. Further, the measured value of the concentration of the organic solvent is input to the control unit 130. Based on the input measured value of the concentration of the organic solvent, the control unit 130 issues an operation command to open any one of the first valve 32b, the second valve 33b, and the third valve 34b and close the other valves. For example, in the case of the separation liquid with the lowest concentration of the organic solvent, the control unit 130 issues an operation command to open the first valve 32b and close the second valve 33b and the third valve 34b. Thereby, the separation liquid with a low concentration of the organic solvent is stored as the first separation liquid in the first separation liquid storage tank 32c via the first supply pipe 32a. In this way, in this step, the separation liquid can be stored in any one of the first separation liquid storage tank 32c, the second separation liquid storage tank 33c, or the third separation liquid storage tank 34c for each different concentration of the organic solvent.

[0072] Furthermore, in the storage step, with respect to the first separation liquid stored in the first separation liquid storage tank 32c, while circulating the first separation liquid through the first separation liquid circulation path 32d, impurities in the first separation liquid are separated and removed by the first filter 32g. The circulation of the first separation liquid in the first separation liquid circulation path 32d is performed by operating the first pump 32f. This step is also performed for the second separation liquid and the third separation liquid stored in the second separation liquid storage tank 33c and the third separation liquid storage tank 34c, respectively, and impurities are removed using the second filter 33g and the third filter 34g in the second separation liquid circulation path 33d or the third separation liquid circulation path 34d, respectively.

[0073] The supply step is a step of generating a treatment liquid containing at least any one of the first separation liquid to the third separation liquid independently stored in the storage step and supplying it to the surface Wf of the substrate W. In this step, in order to use it as a rinse liquid and remove the water remaining on the surface Wf of the substrate W, the treatment liquid can be supplied onto the surface Wf of the substrate W and replaced with the treatment liquid.

[0074] Here, on the surface Wf of the substrate W, the most water remains immediately after substrate processing. Therefore, even if a processing liquid composed only of an organic solvent is supplied onto the surface Wf of the substrate W to replace and remove the water, since the organic solvent is a liquid that is inherently low in compatibility with water, it takes a certain amount of time or more to replace the water with the organic solvent. However, after replacing the water with a processing liquid having a low concentration of the organic solvent and then sequentially supplying processing liquids having a higher concentration of the organic solvent step by step, it is possible to replace and remove the water with the processing liquid composed of the organic solvent in a shorter time compared to the case where the processing liquid composed of the organic solvent is supplied from the beginning. Therefore, in this step, first, the first valve 133 is opened according to the operation command of the control unit 130, and the second valve 134 and the third valve 135 are closed, and the first separation liquid having the lowest concentration of the organic solvent is supplied from the first separation liquid storage tank 32c to the connection part 131 through the first separation liquid supply pipe 32e. Further, by opening the valve 132 according to the operation command of the control unit 130, the processing liquid composed of the first separation liquid is supplied onto the surface Wf of the substrate W through the supply pipe 13c and the nozzle 31a. Thereby, the water remaining on the surface Wf of the substrate W can be replaced with the processing liquid having the lowest concentration of the organic solvent.

[0075] Next, in order to replace the processing liquid composed of the first separation liquid remaining on the surface Wf of the substrate W with a processing liquid composed of a second separation liquid having a higher organic solvent concentration than the first separation liquid, the control unit 130 issues an operation command to open the second valve 134 and the valve 132, and to close the first valve 133 and the third valve 135. Subsequently, in order for the control unit 130 to replace the processing liquid composed of the second separation liquid remaining on the surface Wf of the substrate W with a processing liquid composed of a third separation liquid having a higher organic solvent concentration than the second separation liquid, the control unit 130 issues an operation command to open the third valve 135 and the valve 132, and to close the first valve 133 and the second valve 134. Finally, in order for the control unit 130 to replace the processing liquid composed of the third separation liquid remaining on the surface Wf of the substrate W with a processing liquid composed only of an organic solvent, the control unit 130 issues an operation command to open the valve 137 and to close the first valve 133, the second valve 134, and the third valve 135. In this way, the control unit 130 sequentially supplies processing liquids with a higher organic solvent concentration in stages, and finally supplies a processing liquid composed only of an organic solvent, so that the water remaining on the surface Wf of the substrate W can be replaced with the processing liquid and removed in a shorter time than before.

[0076] Incidentally, the concentration of the organic solvent contained in the processing liquid supplied to the substrate W may be adjusted by appropriately mixing the first to third separation liquids supplied from the separation liquid storage unit 30, the unused organic solvent supplied from the organic solvent supply unit 13d, and the unused water supplied from the water supply unit 13e. In this case, the control unit 130 issues an operation command to independently open and close the first valve 133, the second valve 134, and the third valve 135 while adjusting the flow rate with the flow rate adjustment valve 143. Further, the control unit 130 issues an operation command to open and close the valve 137 while adjusting the flow rate with the flow rate adjustment valve 145 for the organic solvent supply unit 13d, and also issues an operation command to open and close the valve 140 while adjusting the flow rate with the flow rate adjustment valve 147 for the water supply unit 13e.

[0077] (Second Embodiment) The second embodiment of the present invention will be described below.

[0078] [Substrate Processing Apparatus] <Overall Configuration of Substrate Processing Apparatus and Substrate Processing Unit> The substrate processing apparatus according to the second embodiment has basically the same configuration as the substrate processing apparatus 100 according to the first embodiment, except for the recovery and reuse unit of the substrate processing unit 110 (see FIG. 1). Therefore, detailed descriptions of the indexer unit 120, the control unit 130, and the substrate processing unit 1 of the substrate processing unit 110 are omitted by attaching the same reference numerals.

[0079] <Recovery and Reuse Unit> Next, the configuration of the recovery and reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 3. FIG. 3 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery and reuse unit 2' in the substrate processing apparatus of the present embodiment. In FIG. 3, for the sake of clarity of the illustrated directional relationship, the XYZ orthogonal coordinate axes are appropriately displayed. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertically upward direction.

[0080] As shown in FIG. 3, the recovery and reuse unit 2' of the present embodiment is mainly different from the recovery and reuse unit 2 of the first embodiment in that the intermediate drainage storage unit 22 is omitted in the separation unit 20'. Also, in the separation unit 20', the separation liquid discharge pipe 27' for supplying the separation liquid to the separation liquid storage unit 30 is branched from the circulation path 26. More specifically, the separation unit 20' includes at least a recovery pipe 21, a drainage storage unit 24, a separation membrane unit 25, a circulation path 26, a separation liquid discharge pipe 27', and a water discharge pipe 28.

[0081] The recovery pipe 21 directly supplies the drainage discharged from the splash prevention cup 14 to the drainage storage section 24. One end of the recovery pipe 21 is connected to the splash prevention cup 14, and the other end is connected to the drainage storage section 24. Along the path of the recovery pipe 21, a densitometer 21b and a valve 21a are sequentially provided from the upstream side to the downstream side. The valve 21a is electrically connected to the control section 130 and is normally closed. The opening and closing of the valve 21a are controlled by an operation command from the control section 130. Also, the densitometer 21b measures the concentration of the organic solvent in the drainage discharged from the splash prevention cup 14. The measured value of the concentration of the organic solvent in the drainage measured by the densitometer 21b is input to the control section 130. Based on the input measured value of the concentration of the organic solvent in the drainage, the control section 130 issues an operation command for opening and closing the valve 21a.

[0082] In the circulation path 26, a pump 26a, a separation membrane section 25, and a densitometer 26b are sequentially provided from the upstream side to the downstream side. Also, at the branch point where the separated liquid discharge pipe 27' branches from the circulation path 26, a three-way valve 41 is provided. By providing the three-way valve 41 at the branch point, the flow path of the separated liquid flowing through the circulation path 26 can be changed to the separated liquid discharge pipe 27'. The three-way valve 41 is electrically connected to the control section 130, and the change of the flow path by the three-way valve 41 is controlled by an operation command from the control section 130.

[0083] The separated liquid discharge pipe 27' branches from the circulation path 26 and is connected to the separated liquid storage section 30. Also, along the path of the separated liquid discharge pipe 27', a filter 27a is provided upstream of the branch point where it branches from the first supply pipe 32a of the first separated liquid storage section 32. The filter 27a can remove solids such as particles and impurities such as metal ions contained in the separated liquid. When removing metal ions, as the filter 27a, for example, an ion exchange resin or the like can be used.

[0084] [Substrate Processing Method] Next, a substrate processing method using the substrate processing apparatus 100 of the present embodiment will be described below. The substrate processing method of this embodiment, similar to the case of the first embodiment, includes a drainage step of draining the processing liquid after substrate processing, a separation step of collecting the drainage and removing at least a part of water from the drainage, a storage step of independently storing the separated liquid generated in the separation step for each different concentration of the organic solvent contained in the separated liquid, and a supply step of supplying a processing liquid containing at least any one of the separated liquids independently stored in the storage step to the surface Wf of the substrate W. In this embodiment, since the supply step is the same as that in the first embodiment, the description thereof will be omitted below.

[0085] In the drainage step, when the processing liquid collected by the splash prevention cup 14 is discharged as drainage through the recovery pipe 21, the concentration of the organic solvent in the drainage is measured by a concentration meter 21b provided in the middle of the path of the recovery pipe 21. Further, the measured value of the concentration of the organic solvent is input to the control unit 130. When it is determined that the measured value is a predetermined value, the control unit 130 issues an operation command to open the valve 21a. Thereby, the drainage having a concentration of the organic solvent of a predetermined value is supplied to the drainage storage unit 24. When a predetermined amount of drainage is stored in the drainage storage unit 24, the control unit 130 issues an operation command to close the valve 21a.

[0086] Subsequently, in the separation step, at least a part of the water contained in the drainage stored in the drainage storage unit 24 is removed. That is, the drainage stored in the drainage storage unit 24 is circulated through the circulation path 26 by the operation of the pump 26a. The drainage flowing through the circulation path 26 is separated and removed at least a part of the water contained in the drainage in the separation membrane unit 25 provided in the middle of the path of the circulation path 26. The drainage from which at least a part of the water has been removed is discharged as a separated liquid from the separation membrane unit 25. Also, the water separated by the separation membrane unit 25 is discharged from the water discharge pipe 28. Further, the concentration of the organic solvent contained in the separated liquid is measured by the concentration meter 26b for the separated liquid discharged from the separation membrane unit 25. When the measured value of the concentration of the organic solvent is input to the control unit 130 and it is determined that the measured value has reached a predetermined value, the control unit 130 issues an operation command to the three-way valve 41 to change the flow path to the separated liquid discharge pipe 27'. Thereby, the separated liquid is sent to the separated liquid storage unit 30 through the separated liquid discharge pipe 27'. On the other hand, when it is determined that the measured value of the concentration of the organic solvent has not reached the predetermined value, no operation command for changing the flow path is issued to the three-way valve 41, and the separated liquid is returned to the drainage storage unit 24 through the circulation path 26. The circulation of the separated liquid in the circulation path 26 is continued until the measured value of the concentration of the organic solvent by the concentration meter 26b reaches a predetermined value. Thereby, the separated liquid in which the concentration of the organic solvent has reached a predetermined value is stored in the drainage storage unit 24. Note that since a filter 27a is provided in the middle of the path of the separated liquid discharge pipe 27, impurities such as particles are removed from the separated liquid flowing through the separated liquid discharge pipe 27. Also, during the separation step, it is preferable that the first valve 32b of the first separated liquid storage unit 32, the second valve 33b of the second separated liquid storage unit 33, and the third valve 34b of the third separated liquid storage unit 34 are closed by the operation command of the control unit 130.

[0087] In the storage step, based on the measured value of the concentration of the organic solvent in the separated liquid by the concentration meter 26b of the separation unit 20', the control unit 130 opens any one of the first valve 32b, the second valve 33b, and the third valve 34b, and issues an operation command to close the other valves. For example, in the case of the separated liquid with the lowest concentration of the organic solvent, the control unit 130 issues an operation command to open the first valve 32b and close the second valve 33b and the third valve 34b. As a result, the separated liquid with a low concentration of the organic solvent is stored in the first separated liquid storage tank 32c via the first supply pipe 32a. In this way, in this step, the separated liquid can be stored in any one of the first separated liquid storage tank 32c, the second separated liquid storage tank 33c, or the third separated liquid storage tank 34c for each different concentration of the organic solvent. In the storage step, the first to third separated liquids independently stored in any one of the first separated liquid storage section, the second separated liquid storage section, or the third separated liquid storage section are reused as a processing liquid in the supply step in the same manner as in the first embodiment.

[0088] (Third Embodiment) The third embodiment of the present invention will be described below.

[0089] [Substrate Processing Apparatus] <Overall Configuration of Substrate Processing Apparatus and Substrate Processing Unit> The substrate processing apparatus according to the third embodiment has basically the same configuration as the substrate processing apparatus 100 according to the first and second embodiments except for the recovery and reuse unit of the substrate processing unit 110 (see FIG. 1). Therefore, detailed descriptions of the indexer unit 120, the control unit 130, and the substrate processing unit 1 of the substrate processing unit 110 are omitted by attaching the same reference numerals.

[0090] <Recovery and Reuse Unit> Next, the configuration of the recovery and reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 4. FIG. 4 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery and reuse unit 2” in the substrate processing apparatus of the present embodiment. In FIG. 4, for the sake of clarity of the illustrated directional relationship, the XYZ orthogonal coordinate axes are appropriately displayed. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertically upward direction.

[0091] As shown in FIG. 4, the recovery and reuse unit 2” of the present embodiment mainly differs in that, compared with the recovery and reuse unit 2’ of the second embodiment, it uses a separation unit 20” provided with two first separation membrane parts 25a and second separation membrane parts 25b, and by enabling the change of the flow path of the drain liquid (or separation liquid), the separation performance can be changed. More specifically, the separation unit 20” includes at least a recovery pipe 21, a drain liquid storage part 24, a first separation membrane part 25a and a second separation membrane part 25b, a circulation path 26, a separation liquid discharge pipe 27”, a first water discharge pipe 28a and a second water discharge pipe 28b, and a bypass path 29.

[0092] In the circulation path 26, a pump 26a, a first separation membrane part 25a, a first concentration meter 42a, a second separation membrane part 25b, and a second concentration meter 42b are sequentially provided from the upstream side to the downstream side. Further, a bypass path 29 for bypassing the second separation membrane part 25b is provided in the circulation path 26. Thus, in the present embodiment, it is possible to form a first path in which the drain liquid (or separation liquid) flows only through the circulation path 26, and a second path in which the drain liquid (or separation liquid) flows through a part of the circulation path 26 and the bypass path 29. In the first path, more water can be separated and removed from the drain liquid (or separation liquid) using the two separation membrane parts of the first separation membrane part 25a and the second separation membrane part 25b, so that a separation liquid with a high concentration of the organic solvent can be generated. On the other hand, in the second path, water is separated and removed from the drain liquid (or separation liquid) only by the first separation membrane part 25a, so that a separation liquid with a relatively low concentration of the organic solvent can be generated.

[0093] The first separation membrane part 25a can separate and remove at least a part of the water contained in the drainage liquid stored in the drainage storage part 24 from the drainage liquid. Further, the second separation membrane part 25b can separate and remove at least a part of the water contained in the separated liquid discharged from the first separation membrane part 25a from the separated liquid. As the separation membrane used for the first separation membrane part 25a and the second separation membrane part 25b, the same one as the separation membrane in the separation membrane part 25 in the first embodiment can be used. Incidentally, the water separated by the first separation membrane part 25a is discharged from the first water discharge pipe 28a, and the water separated by the second separation membrane part 25b is discharged from the second water discharge pipe 28b.

[0094] As described above, since the first separation membrane part 25a and the second separation membrane part 25b are provided in the circulation path 26, the separated liquid obtained by separating at least a part of the water contained in the drainage liquid by these can be returned to the drainage storage part 24. Further, a pump 26a is provided in the middle of the path of the circulation path 26, on the downstream side of the drainage storage part 24 and on the upstream side of the first separation membrane part 25a. Furthermore, on the downstream side of the first separation membrane part 25a, a first concentration meter 42a for measuring the concentration of an organic solvent such as IPA in the separated liquid generated by the first separation membrane part 25a is provided. Also, on the downstream side of the second separation membrane part 25b, a second concentration meter 42b for measuring the concentration of an organic solvent such as IPA in the separated liquid generated by the second separation membrane part 25b is provided. The measured values of the concentration of the organic solvent in the separated liquid measured by the first concentration meter 42a and the second concentration meter 42b are input to the control unit 130.

[0095] The bypass circuit 29 is provided such that the separated liquid generated in the first separation membrane section 25a flows around the second separation membrane section 25b. More specifically, the bypass circuit 29 branches downstream of the first concentration meter 42a in the circulation path 26 and merges into the circulation path 26 downstream of the second concentration meter 42b. A first three-way valve 44 is provided at the branch point where the bypass circuit 29 branches from the circulation path 26, and a second three-way valve 45 is provided at the merge point where it merges into the circulation path 26. By providing the first three-way valve 44 at the branch point, the flow path of the separated liquid flowing through the circulation path 26 can be changed to the bypass circuit 29. Also, by providing the second three-way valve 45 at the merge point, the flow path of the separated liquid flowing through the bypass circuit 29 can be changed to the circulation path 26. The first three-way valve 44 and the second three-way valve 45 are electrically connected independently of the control unit 130, and the change of the flow path by the first three-way valve 44 and the second three-way valve 45 is controlled by the operation command of the control unit 130.

[0096] Also, a first filter 43a and a second filter 43b are sequentially provided in the bypass circuit 29 from the upstream side toward the downstream side. Further, in the bypass circuit 29, a separated liquid discharge pipe 27” is connected to the pipeline between the first filter 43a and the second filter 43b. The first filter 43a and the second filter 43b can remove solids such as particles and impurities such as metal ions contained in the separated liquid. When removing metal ions, as the first filter 43a and the second filter 43b, for example, an ion exchange resin or the like can be used.

[0097] The separated liquid discharge pipe 27” branches from the bypass circuit 29 and is connected to the separated liquid storage section 30. A three-way valve 43c is provided at the branch point where the separated liquid discharge pipe 27” branches from the bypass circuit 29. By providing the three-way valve 43c at the branch point, the flow path of the separated liquid flowing through the bypass circuit 29 can be changed to the separated liquid discharge pipe 27”. The three-way valve 43c is electrically connected to the control unit 130, and the change of the flow path by the three-way valve 43c is controlled by the operation command of the control unit 130.

[0098] [Substrate Processing Method] Next, a substrate processing method using the substrate processing apparatus 100 of the present embodiment will be described below. Similar to the cases of the first and second embodiments, the substrate processing method of the present embodiment includes a drainage step of draining the processing liquid after substrate processing, a separation step of recovering the drainage and removing at least a part of water from the drainage, a storage step of independently storing the separated liquid generated in the separation step for each different concentration of the organic solvent contained in the separated liquid, and a supply step of supplying a processing liquid containing at least any one of the separated liquids independently stored in the storage step to the surface Wf of the substrate W. In the present embodiment, since the drainage step is the same as that in the second embodiment and the supply step is the same as that in the first embodiment, these descriptions will be omitted below.

[0099] In the separation process, at least a part of the water contained in the drainage stored in the drainage storage unit 24 is removed. When removing water from the drainage in the first path, the drainage stored in the drainage storage unit 24 is circulated through the circulation path 26 by the operation of the pump 26a. The drainage flowing through the circulation path 26 is separated and removed of at least a part of the water contained in the drainage in the first separation membrane unit 25a provided in the middle of the path of the circulation path 26. The drainage from which at least a part of the water has been removed is discharged as a separated liquid from the first separation membrane unit 25a. Also, the water separated by the first separation membrane unit 25a is discharged from the first water discharge pipe 28a. Further, for the separated liquid discharged from the first separation membrane unit 25a, the concentration of the organic solvent contained in the separated liquid is measured by the first concentration meter 42a. When the measured value of the concentration of the organic solvent is input to the control unit 130 and it is determined that the value has not reached a predetermined value, no operation command for changing the flow path for the first three-way valve 44 is given, and the separated liquid is supplied to the second separation membrane unit 25b. Further, in the second separation membrane unit 25b, at least a part of the water contained in the separated liquid is removed. The water separated by the second separation membrane unit 25b is discharged from the second water discharge pipe 28b. Also, the control unit 130 gives an operation command to the second three-way valve 45 so that the circulation path 26 and the bypass path 29 do not communicate. Thereby, the separated liquid from which more water has been removed by the second separation membrane unit 25b flows through the circulation path 26 as it is and is returned to the drainage storage unit 24. The circulation of the separated liquid in the circulation path 26 is continued until the measured value of the concentration of the organic solvent by the second concentration meter 42b reaches a predetermined value. As a result, more water is removed, and a separated liquid with a high concentration of organic solvent is obtained and stored in the drainage storage unit 24.

[0100] On the other hand, when removing water from the drainage liquid in the second path, the drainage liquid stored in the drainage liquid storage unit 24 is circulated through the circulation path 26 by the operation of the pump 26a and supplied to the first separation membrane unit 25a. After at least a part of the water in the drainage liquid is removed in the first separation membrane unit 25a, the concentration of the organic solvent contained in the separation liquid thus obtained is measured by the first concentration meter 42a. When the measured value of the concentration of the organic solvent is input to the control unit 130 and it is determined that the measured value has reached a predetermined value, the control unit 130 issues an operation command to the first three-way valve 44 to change the flow path from the circulation path 26 to the bypass path 29. As a result, the separation liquid is sent to the bypass path 29. Here, when supplying the separation liquid to the separation liquid storage unit 30, the control unit 130 also issues an operation command to the three-way valve 43c to change the flow path from the bypass path 29 to the separation liquid discharge pipe 27". As a result, the separation liquid flowing through the bypass path 29 is sent to the separation liquid storage unit 30 via the separation liquid discharge pipe 27". On the other hand, when storing the separation liquid in the drainage liquid storage unit 24, the control unit 130 does not issue an operation command to the three-way valve 43c to change the flow path from the bypass path 29 to the separation liquid discharge pipe 27". Further, the control unit 130 issues an operation command to the second three-way valve 45 to change the flow path from the bypass path 29 to the downstream side of the circulation path 26. As a result, the separation liquid flowing through the bypass path 29 merges into the circulation path 26 and then returns to the drainage liquid storage unit 24. Incidentally, a first filter 43a and a second filter 43b are provided in the middle of the bypass path 29. Therefore, impurities such as particles are removed from the separation liquid supplied to the drainage liquid storage unit 24 and the separation liquid storage unit 30. Also, during the separation process, it is preferable that the first valve 32b of the first separation liquid storage unit 32, the second valve 33b of the second separation liquid storage unit 33, and the third valve 34b of the third separation liquid storage unit 34 are closed by the operation command of the control unit 130.

[0101] In the storage step, based on the measured values of the concentration of the organic solvent in the separated liquid by the first concentration meter 42a and the second concentration meter 42b of the separation unit 20”, the control unit 130 issues an operation command to open any one of the first valve 32b, the second valve 33b, and the third valve 34b and close the other valves. For example, when the concentration of the organic solvent in the separated liquid is the lowest, the control unit 130 issues an operation command to open the first valve 32b and close the second valve 33b and the third valve 34b. As a result, the separated liquid with a low concentration of the organic solvent is stored in the first separated liquid storage tank 32c via the first supply pipe 32a. In this way, in this step, the separated liquid can be stored in any one of the first separated liquid storage tank 32c, the second separated liquid storage tank 33c, or the third separated liquid storage tank 34c for each different concentration of the organic solvent. In the storage step, the first to third separated liquids independently stored in any one of the first separated liquid storage section, the second separated liquid storage section, or the third separated liquid storage section are reused as the processing liquid in the supply step in the same manner as in the first and second embodiments.

[0102] (Other matters) In the above description, the most preferred embodiment of the present invention has been described. However, the present invention is not limited to this embodiment, and various modifications can be made within a range substantially the same as the technical idea described in the claims of the present invention.

[0103] For example, in the first to third embodiments, the case where three, i.e., the first separated liquid storage section, the second separated liquid storage section, and the third separated liquid storage section, are provided as the separated liquid storage sections has been described as an example. However, the present invention is not limited to this aspect, and it is sufficient to have at least two or more separated liquid storage sections. In this case, the configuration of the supply section can also be appropriately changed according to the number of the separated liquid storage sections. More specifically, according to the number of the separated liquid storage sections, the number of the separated liquid supply pipes for supplying the separated liquid to the multi-way valve, and the valves, pumps, and flow rate adjustment valves provided in the middle of the path of the separated liquid supply pipes can be appropriately changed.

[0104] In addition, in the first to third embodiments, the case where the water separated from the drainage liquid (or separation liquid) in the separation membrane section is discarded from the water discharge pipe has been described as an example. However, the present invention is not limited to this aspect, and the separated water may be reused. In this case, for example, the water discharge pipe for discarding water may be connected to the water storage section of the water supply section for supplying unused water. Thereby, the water separated in the separation membrane section can be contained in the treatment liquid instead of the unused water and reused.

Explanation of Signs

[0105] 1: Substrate processing unit, 2, 2’, 2”: Recycling and reuse unit, 13: Supply unit, 13a: Nozzle, 13b: Multi-way valve, 13c: Supply pipe, 13d: Organic solvent supply unit, 13e: Water supply unit, 14: Anti-scattering cup, 20, 20’, 20”: Separation unit, 21: Recovery pipe, 21a: Valve, 21b: Concentration meter, 22: Intermediate drain storage unit, 23: Drain discharge pipe, 23a: Valve, 23b: Pump, 24: Drain storage unit, 24a: Drain temperature adjustment unit, 25: Separation membrane unit, 25a: First separation membrane unit, 25b: Second separation membrane unit, 26: Circulation path, 26a: Pump, 26b: Concentration meter, 27, 27’, 27”: Separation liquid discharge pipe, 27a: Filter, 28: Water discharge pipe, 28a: First water discharge pipe, 28b: Second water discharge pipe, 29: Bypass, 30: Separation liquid storage unit, 31: Concentration meter, 31a: Nozzle, 32: First separation liquid storage unit, 32a: First supply pipe, 32b: First valve, 32c: First separation liquid storage tank, 32d: First separation liquid circulation path, 32e: First separation liquid supply pipe, 32f: First pump, 32g: First filter, 33: Second separation liquid storage unit, 33a: Second supply pipe, 33b: Second valve, 33c: Second separation liquid storage tank, 33d: Second separation liquid circulation path, 33e: Second separation liquid supply pipe, 33f: Second pump, 33g: Second filter, 34: Third separation liquid storage unit, 34a: Third supply pipe, 34b: Third valve, 34c: Third separation liquid storage tank, 34d: Third separation liquid circulation path, 34e: Third separation liquid supply pipe, 34f: Third pump, 34g: Third filter, 41: Three-way valve, 42a: First concentration meter, 42b: Second concentration meter, 43a: First filter, 43b: Second filter, 43c: Three-way valve, 44: First three-way valve, 45: Second three-way valve, 130: Control unit, 131: Connection unit, 132: Valve, 133: First valve, 134: Second valve, 135: Third valve, 136: Supply pipe, 137: Valve, 138: Organic solvent storage unit, 139: Supply pipe, 141: Water storage unit, W: Substrate, Wf: Surface

Claims

1. A substrate processing apparatus for processing a pattern formation surface of a substrate, comprising: a separation unit configured to collect a drainage liquid discharged after the substrate processing and containing an organic solvent and water, and remove at least a part of the water from the collected drainage liquid; a plurality of separation liquid storage units configured to independently store the separation liquid generated by removing at least a part of the water from the drainage liquid by the separation unit, for each different concentration of the organic solvent contained in the separation liquid; a supply unit configured to supply a processing liquid containing at least any one of the separation liquids independently stored in the plurality of separation liquid storage units to the pattern formation surface of the substrate; A substrate processing apparatus comprising the above components.

2. The plurality of separation liquid storage units are provided with separation liquid circulation paths for deriving the stored separation liquid and returning it to their respective separation liquid storage units, and a filter for removing impurities contained in the separation liquid is provided in the middle of the separation liquid circulation path. The substrate processing apparatus according to claim 1.

3. The separation unit includes: a drainage liquid storage unit for storing the collected drainage liquid; a separation membrane unit for separating and removing at least a part of the water from the drainage liquid derived from the drainage liquid storage unit; a circulation path for supplying the drainage liquid stored in the drainage liquid storage unit to the separation membrane unit and returning the separation liquid generated by the separation membrane unit to the drainage liquid storage unit; a water discharge pipe connected to the separation membrane unit for discharging the water separated by the separation membrane unit; The substrate processing apparatus according to claim 1, comprising the above components.

4. The supply unit includes a multi-way valve configured to selectively supply the processing liquid containing at least any one of the separation liquids supplied from the plurality of separation liquid storage units to the pattern formation surface. The substrate processing apparatus according to claim 1.

5. The supply unit further includes an organic solvent supply unit for supplying an unused organic solvent and a water supply unit for supplying unused water, and the multi-way valve mixes the organic solvent supplied from the organic solvent supply unit and / or the water supplied from the water supply unit with the separation liquid supplied from at least any one of the plurality of separation liquid storage units to generate the processing liquid. The substrate processing apparatus according to claim 4.

6. A substrate processing method for processing a pattern formation surface of a substrate, comprising: a separation step of collecting a drainage liquid discharged after the substrate processing and containing an organic solvent and water, and removing at least a part of the water from the collected drainage liquid; a storage step of independently storing a separated liquid produced by removing at least a part of the water from the discharged liquid in the separation step, the separated liquid having a different concentration of the organic solvent contained therein; a supplying step of supplying a processing liquid containing at least one of the separating liquids, each of which is stored independently, onto a pattern forming surface of the substrate; A method for processing a substrate, comprising:

7. 7. The substrate processing method according to claim 6, wherein the storing step comprises discharging the stored separated liquid, removing impurities from the separated liquid, and then returning the separated liquid to circulate it.

8. The separation step comprises: storing the collected effluent; separating and removing at least a portion of the water contained in the drainage liquid while circulating the drainage liquid; Discharging the water separated from the effluent; The method of claim 6 , further comprising:

9. 7. The substrate processing method according to claim 6, wherein the supplying step selectively supplies the processing liquid containing at least any one of the separating liquids to be supplied, onto the pattern formation surface.

10. 10. The substrate processing method according to claim 9, wherein the supplying step generates the processing liquid by mixing at least one of the separation liquids stored in the storing step with an unused organic solvent and / or unused water.

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