Recovery and recycling unit, substrate processing apparatus having the same and substrate processing method

Abstract

To provide a recovery and recycling unit that reduces the amount of organic solvent waste while suppressing an increase in operating cost, thereby enabling a reduction in environmental impact, a substrate processing apparatus having the same and a substrate processing method.SOLUTION: A recovery and recycling unit 2 for recovering and recycling waste liquid discharged after substrate processing, comprises at least a separation section 20 for recovering waste liquid containing organic solvents and water, and separating the organic solvents from the recovered waste liquid, and the separation section 20 comprises a bubble generation section 24 that generates gas bubbles 202 in which organic solvents are adsorbed onto the surface by mixing gas into the waste liquid discharged after substrate processing, a swivel flow generation section 25 that generates a swivel flow in the waste liquid containing the bubbles 202, and a recovery section for recovering vaporized organic solvent gas generated from the swivel flow and / or organic solvent concentrated in the central portion of the swivel flow.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a recovery and reuse unit capable of recovering and reusing waste liquid discharged after substrate processing, a substrate processing apparatus including the same, and a substrate processing method. [Background technology]

[0002] In the manufacturing process of semiconductor devices and liquid crystal display devices, substrates such as semiconductor wafers and glass substrates for liquid crystal display devices are treated with a treatment liquid. Specifically, a chemical liquid is supplied to the main surface of the substrate to perform the chemical treatment on the substrate, and then a rinsing process is performed in which water such as deionized water (DIW) is supplied to the main surface of the substrate to wash away the chemical liquid on the substrate. Furthermore, after the rinsing process, a drying process is performed to remove water remaining on the substrate and dry the substrate.

[0003] On the other hand, 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 convex portion of the pattern) of the convex portion of the pattern having concaves and convexes has been increasing. Therefore, during a drying process, the surface tension acting on the interface between water that has entered the concave portion of the pattern and the gas in contact with the water attracts adjacent convex portions in the pattern, causing them to collapse, resulting in a problem known as pattern collapse. To address this problem of pattern collapse, for example, Patent Document 1 proposes a technique for drying the substrate by replacing water on the substrate with isopropyl alcohol (IPA). Here, in substrate processing using an organic solvent such as IPA, a wastewater mixture of water and the organic solvent is discharged. Therefore, from the perspective of reducing environmental impact, reuse of the wastewater has been investigated. As a technology for reusing such wastewater, for example, a method has been proposed in which water is separated from the wastewater by membrane separation using a zeolite membrane or the like, and the organic solvent is recovered and reused (Patent Document 2). This membrane separation technology does not require large-scale equipment, and can reduce equipment costs and energy consumption compared to distillation using a distillation column, for example. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-38595 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-41505 Summary of the Invention [Problem to be solved by the invention]

[0005] However, because separation membranes such as zeolite membranes have a short lifespan, their separation performance deteriorates in a short period of time compared to other separation technologies such as distillation. Therefore, to maintain good separation performance, the separation membranes must be replaced, which poses a problem of increased running costs for reusing wastewater.

[0006] The present invention has been made in consideration of the above-mentioned problems, and an object of the present invention is to provide a recovery and reuse unit that enables reduction in the amount of organic solvent waste and reduction in environmental load while suppressing an increase in running costs, as well as a substrate processing apparatus and a substrate processing method that include the same. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the recovery and reuse unit of the present invention is a recovery and reuse unit that recovers and reuses waste liquid discharged after substrate processing, and includes at least a separation section that recovers the waste liquid containing an organic solvent and water and separates the organic solvent from the recovered waste liquid, and the separation section includes: a bubble generation section that mixes a gas with the waste liquid discharged after the substrate processing to generate bubbles of the gas with the organic solvent adsorbed on the surface; a swirling flow generation section that generates a swirling flow in the waste liquid containing the bubbles; and a recovery section that recovers vaporized gas of the organic solvent generated from the swirling flow and / or the organic solvent concentrated in a central portion of the swirling flow.

[0008] In the above configuration, the swirling flow generating unit includes a storage tank that stores the waste liquid containing the gas bubbles, and a rotation drive unit that rotates the storage tank about the central axis of the storage tank to generate a swirling flow in the waste liquid containing the gas bubbles, and the recovery unit includes a condensation unit that liquefies the vaporized gas to produce an organic solvent.

[0009] In the above configuration, the swirl flow generating unit may include a storage tank that stores the waste liquid containing the gas bubbles, and a rotation drive unit that rotates the storage tank about a central axis of the storage tank to generate a swirl flow in the waste liquid containing the gas bubbles, and the recovery unit may include a suction unit that sucks in the gas bubbles that gather in a central portion of the swirl flow and the organic solvent that is concentrated in the central portion.

[0010] In the above configuration, the recovery section may further include a condensation section that liquefies the vaporized gas to produce an organic solvent.

[0011] In the above configuration, a supply pipe for flowing the waste liquid containing the bubbles is connected to the bubble generating section, the swirling flow generating section is provided inside the supply pipe, and further, a straight pipe section of a double pipe structure having an inner pipe and an outer pipe is connected to the downstream side of the supply pipe as the recovery section, and the organic solvent and the bubbles concentrated in the central part of the swirling flow are flowed through the inner pipe, and the water separated outside the central part of the swirling flow is flowed through the gap formed between the inner pipe and the outer pipe, thereby separating and recovering the organic solvent.

[0012] In order to solve the above-mentioned problems, a substrate processing apparatus according to the present invention is characterized by comprising a substrate processing unit that processes a pattern-formed surface of a substrate, and the above-mentioned recovery / reuse unit.

[0013] In order to solve the above-mentioned problems, the substrate processing method of the present invention is a substrate processing method for processing a pattern-formed surface of a substrate, and includes at least a separation step of recovering a waste liquid discharged after the substrate processing and containing an organic solvent and water, and separating the organic solvent from the recovered waste liquid, wherein the separation step includes a bubble generation step of mixing a gas with the waste liquid discharged after the substrate processing to generate bubbles of the gas with the organic solvent adsorbed on the surface thereof, a swirling flow generation step of generating a swirling flow in the waste liquid containing the bubbles, and a recovery step of recovering vaporized gas of the organic solvent generated from the swirling flow and / or the organic solvent concentrated in a central portion of the swirling flow.

[0014] In the above configuration, the swirling flow generating step is a step of storing the waste liquid containing the bubbles in a storage tank and rotating the storage tank around a central axis of the storage tank to generate a swirling flow in the waste liquid containing the bubbles, and the recovery step may include a condensation step of liquefying the vaporized gas to produce an organic solvent.

[0015] In the above-described configuration, the swirling flow generating step may be a step of storing the wastewater containing the gas bubbles in a storage tank and rotating the storage tank around a central axis of the storage tank to generate a swirling flow in the wastewater containing the gas bubbles, and the recovering step may be a step of aspirating and recovering the gas bubbles that gather in a central portion of the swirling flow and the organic solvent that is concentrated in the central portion.

[0016] The recovery step may be a step of liquefying the vaporized gas to generate and recover an organic solvent.

[0017] In the above configuration, the swirling flow generating step is a step of generating the swirling flow inside a supply pipe that flows the waste liquid containing the bubbles, and a straight pipe section of a double pipe structure having an inner pipe and an outer pipe is connected to the downstream side of the supply pipe, and the recovery step may be a step of flowing the organic solvent and the bubbles concentrated in the central part of the swirling flow into the inner pipe, and flowing the water separated outside the central part of the swirling flow into a gap section formed between the inner pipe and the outer pipe, thereby separating and recovering the organic solvent. [Effects of the Invention]

[0018] According to the present invention, after substrate processing, wastewater containing water and an organic solvent is collected, and then a gas is mixed with the wastewater to generate bubbles. Furthermore, a swirling flow is generated in the wastewater containing the bubbles, and at least the bubbles that gather in the center of the swirling flow are collected. Here, the organic solvent contained in the wastewater is adsorbed on the surface of the bubbles, so the organic solvent is separated from the water and concentrated in the center of the swirling flow. The organic solvent can then be recovered from the wastewater by recovering the organic solvent vapor generated mainly from the center of the swirling flow and / or recovering the organic solvent concentrated in the center of the swirling flow. This allows the organic solvent to be separated from water and recovered, reducing waste while suppressing increases in running costs compared to conventional techniques that recover organic solvents by membrane separation using a separation membrane. As a result, the present invention provides a recovery and reuse unit that can reduce the environmental impact of substrate processing, as well as a substrate processing apparatus and a substrate processing method equipped with the same. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a plan view showing a schematic configuration of a substrate processing apparatus according to a first embodiment of the present invention. [Figure 2] FIG. 1 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a first embodiment of the present invention. [Figure 3]1 is a cross-sectional view showing a schematic configuration of a bubble generating section in a recovery and reuse unit according to a first embodiment of the present invention. FIG. [Figure 4] 2 is an explanatory diagram showing a schematic configuration of a swirling flow generating section in the recovery and reuse unit according to the first embodiment of the present invention. FIG. [Figure 5] FIG. 10 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a second embodiment of the present invention. [Figure 6] FIG. 10 is an explanatory diagram showing a partial configuration of a swirl flow generating section and a suction section in a recovery and reuse unit according to a second embodiment of the present invention. [Figure 7] FIG. 10 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a third embodiment of the present invention. [Figure 8] FIG. 10 is a cross-sectional view showing a schematic configuration of a swirl flow generating section and a straight pipe section in a recovery and reuse unit according to a third embodiment of the present invention. [Figure 9] FIG. 10 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a fourth embodiment of the present invention. [Figure 10] FIG. 10 is an explanatory diagram showing a schematic configuration of a first re-separation section according to a first aspect of a recovery and reuse unit according to a fourth embodiment of the present invention. [Figure 11] FIG. 10 is an explanatory diagram showing a schematic configuration of a second re-separation section according to a second aspect of the recovery and reuse unit according to the fourth embodiment of the present invention. [Figure 12] FIG. 10 is an explanatory diagram schematically illustrating a separated liquid storage section and a heat pipe of a second re-separation section according to a second aspect of the recovery and reuse unit according to a fourth embodiment of the present invention. [Figure 13] An explanatory diagram schematically showing the separated liquid storage section, second irradiation section, annular cooling section, and condensed liquid cooling section of the third re-separation section relating to the third aspect of the recovery and reuse unit of the fourth embodiment of the present invention. [Figure 14] FIG. 10 is an explanatory diagram showing a schematic configuration of a fourth re-separation section according to a fourth aspect of the recovery and reuse unit according to the fourth embodiment of the present invention. [Figure 15]FIG. 10 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a fifth embodiment of the present invention. [Figure 16] FIG. 13 is an explanatory view schematically illustrating a substrate processing unit and a recovery / reuse unit of a substrate processing apparatus according to a sixth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] (First embodiment) A first embodiment of the present invention will be described below with reference to the drawings. However, parts that are not necessary for the description will be omitted, and some parts will be illustrated enlarged or reduced in size to facilitate the description.

[0021] In this specification, the term "substrate" refers to various substrates such as semiconductor substrates, glass substrates for photomasks, glass substrates for liquid crystal displays, glass substrates for plasma displays, substrates for FEDs (Field Emission Displays), substrates for optical disks, substrates for magnetic disks, and substrates for magneto-optical disks. Furthermore, in this specification, the term "pattern-formed surface" refers to a surface of a substrate on which a concave-convex pattern is formed in any region, regardless of whether the surface is flat, curved, or concave-convex. Furthermore, in this specification, the substrate is exemplified as one on which a circuit pattern or the like (hereinafter referred to as "pattern") is formed on only one main surface. Here, the pattern-formed surface (main surface) on which the pattern is formed is referred to as the "surface."

[0022] [Substrate processing equipment] <Overall configuration of substrate processing equipment> A substrate processing apparatus according to this embodiment will be described below with reference to Fig. 1. Fig. 1 is a plan view showing a schematic configuration of a 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 processing such as a rinse process using a rinse liquid and a replacement process with a processing liquid after the rinse process.

[0023] As shown in FIG. 1, the substrate processing apparatus 100 includes a substrate processing section 110 that performs various processes on substrates W, an indexer section 120, and a control section 130 that controls the substrate processing apparatus 100.

[0024] The indexer unit 120 has the function of supplying substrates W to the substrate processing unit 110 or retrieving substrates W from the substrate processing unit 110. Specifically, the indexer unit 120 has four container holders 121, each of which is provided with one container C. Examples of the container C include a FOUP (Front Opening Unified Pod), a SMIF (Standard Mechanical Interface) pod, and an OC (Open Cassette), which accommodate multiple substrates W in a sealed state. Note that, in this embodiment, an example will be described in which there are four container holders 121, but the present invention is not limited to this. There may be more than one container holder 121.

[0025] The indexer unit 120 further includes a first transport unit 122 for transporting substrates W. The first transport unit 122 is provided between the container holding unit 121 and the substrate processing unit 110. The first transport unit 122 includes a base unit 122a fixed to the apparatus housing, an articulated arm 122b rotatable about a vertical axis relative to the base unit 122a, and a hand 122c attached to the tip of the articulated arm 122b. The hand 122c is structured so that a substrate W can be placed on and held on its upper surface. The first transport unit 122 can access a container C held by the container holding unit 121 to remove an unprocessed substrate W from the container C or store a processed substrate W in the container C.

[0026] The substrate processing unit 110 performs a rinse process on the substrate W using a rinse liquid made of water, and a substitution process for substituting the rinse 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 transport unit 111 disposed approximately in the center in a plan view, four substrate processing units 1 disposed to surround the second transport unit 111, and a recovery / reuse unit 2 that recovers and reuses waste liquid discharged from the substrate processing units 1. Details of the substrate processing units 1 and the recovery / reuse unit 2 will be described later.

[0027] For example, a substrate transport robot can be used as the second transport part 111. The second transport part 111 randomly accesses each substrate processing unit 1 to transfer the substrate W. The substrate processing part 110 includes a plurality of substrate processing units 1 and a plurality of recovery / recycling units 2, thereby enabling parallel processing of a plurality of substrates W.

[0028] 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 composed of a computer having an arithmetic processing unit and a memory. The arithmetic processing unit uses a CPU that performs various arithmetic processing. The memory also includes a ROM, which is a read-only memory that stores a substrate processing program, a RAM, which is a read / write memory that stores various information, and a magnetic disk that stores control software, data, etc. The magnetic disk pre-stores substrate processing condition information (processing recipe) corresponding to the substrate W, control condition information for controlling the substrate processing apparatus 100, etc. The CPU reads the substrate processing condition information, control condition information, etc. into the RAM and controls each part of the substrate processing apparatus 100 according to the contents thereof.

[0029] <Substrate processing unit> Next, the configuration of the substrate processing unit 1 in the substrate processing section 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 / recycling unit 2 in the substrate processing apparatus of this embodiment. In FIG. 2, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationships of the illustrated objects. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0030] The substrate processing unit 1 includes at least a chamber 11 which is a container C for accommodating a substrate W, a substrate holding part 12 which holds the substrate W, a supply part 13 which supplies a processing liquid to the substrate W held by the substrate holding part 12, and a splash prevention cup 14 which collects rinsing liquid, processing liquid, etc. which are supplied to the substrate W held by the substrate holding part 12 and discharged outside the peripheral edge of the substrate W.

[0031] 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 the substrate W. A plurality of chuck pins 12c for gripping the peripheral edge of the substrate W are provided upright near the peripheral edge of the spin base 12b. The number of chuck pins 12c is not particularly limited, but it is preferable to provide at least three or more in order to securely hold the circular substrate W. In this embodiment, three chuck pins 12c 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 holds the substrate W by pressing against the outer peripheral edge of the substrate W supported by the substrate support pin.

[0032] The spin base 12b is connected to the rotation drive unit 12a. The rotation drive unit 12a rotates around an axis A along the Z direction in response to an operation command from 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, i.e., around the axis A.

[0033] 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-formed surface of the substrate W. Examples of the processing liquid include a liquid 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 appropriately.

[0034] As shown in FIG. 2, the supply unit 13 includes at least a nozzle 13a, a multiple valve 13b, a supply pipe 13c, and an organic solvent supply unit 13d.

[0035] The nozzle 13a is connected to a supply pipe 13c through 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) that extends horizontally. The arm is rotatable under the control of the control unit 130, and the nozzle 13a moves as the arm rotates. When the processing liquid is not being discharged, the nozzle 13a is positioned at a retracted position outside the peripheral edge of the substrate W and outside the splash prevention cup 14. When the processing liquid is being discharged, the arm is rotated by an operation command from the control unit 130, and the nozzle 13a is positioned above the spin base 12b, i.e., above the center of the surface Wf of the substrate W (on or near the axis A).

[0036] The multiple valve 13b can selectively supply the separation liquid supplied from the recovery / reuse unit 2 as a processing liquid onto the front surface Wf of the substrate W (the recovery / reuse unit 2 and the separation liquid will be described in detail later). The multiple valve 13b includes a connection part 131, a downstream valve 132, and an upstream valve 133.

[0037] The downstream valve 132 is provided midway along the path of the supply pipe 13c, which is connected to the downstream side of the connection part 131. The downstream valve 132 is electrically connected to the control part 130 and is normally closed. The opening and closing of the downstream valve 132 is controlled by an operation command from the control part 130. When the downstream valve 132 is opened by an operation command from the control part 130, the processing liquid is supplied from the nozzle 13a through the supply pipe 13c onto the front surface Wf of the substrate W.

[0038] The upstream valve 133 is provided midway along the route of the separated liquid discharge pipe 28, which is connected to the upstream side of the connection part 131. The upstream valve 133 is electrically connected to the control part 130 and is normally closed. The opening and closing of the upstream valve 133 is independently controlled by an operation command from the control part 130. The separated liquid discharge pipe 28 will be described in detail later.

[0039] The organic solvent supply unit 13d can supply unused organic solvent to the multiple valve 13b. The organic solvent supply unit 13d includes a supply pipe 136 and an organic solvent reservoir 138. The organic solvent reservoir 138 is connected to the upstream side of the supply pipe 136, and the connection unit 131 is connected to the downstream side. A pump 144, a flow rate control valve 145, and a valve 137 are sequentially provided along the supply pipe 136 from upstream to downstream. The organic solvent reservoir 138 stores unused organic solvent. The pump 144 is controlled by an operation command from the control unit 130, and can send unused organic solvent stored in the organic solvent reservoir 138 to the connection unit 131. The flow rate control valve 145 can adjust the flow rate of unused organic solvent supplied from the organic solvent reservoir 138 by operating 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 is controlled by an operation command from the control unit 130. When the valve 137 is opened by the operation command from the control unit 130, an unused organic solvent is supplied to the connection unit 131 through the supply pipe 136. The unused organic solvent is not particularly limited, and examples thereof include IPA.

[0040] The supply unit 13 may further include a water supply unit (not shown). The water supply unit can supply unused water to the multiple valve 13b.

[0041] The splash prevention cup 14 is provided to surround the spin base 12b. The splash prevention cup 14 is connected to a lifting mechanism (not shown) and is movable up and down in the Z direction shown in Fig. 2. When a rinse liquid or a processing liquid is supplied 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 mechanism, and surrounds the substrate W held by the chuck pins 12c from a lateral position. This makes it possible to collect liquids such as rinse liquid and processing liquid that splash from the substrate W or the spin base 12b.

[0042] <Recycling unit> Next, the configuration of the recovery / recycling unit 2 in the substrate processing section 110 will be described below with reference to FIGS.

[0043] The recovery and reuse unit 2 recovers the processing liquid used for substrate processing in the substrate processing unit 1, separates water and an organic solvent such as isopropyl alcohol from the recovered processing liquid, and makes the organic solvent reusable. The recovery and reuse unit 2 may be provided corresponding to a plurality of substrate processing units 1 as shown in Fig. 1, or may be provided individually for each substrate processing unit 1. Specifically, the recovery and reuse unit 2 includes at least a separation section 20, a condensation section 201 as a recovery section, and a separated liquid discharge pipe 28 as shown in Fig. 2.

[0044] The separation unit 20 can recover waste liquid consisting of the processing liquid used in substrate processing and remove water from the recovered waste liquid. The substrate processing here refers to a process of supplying a processing liquid to the surface Wf of the substrate W and replacing 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 waste liquid storage unit 22, a waste liquid discharge pipe 23, a bubble generator 24, and a swirl flow generator 25.

[0045] The recovery pipe 21 supplies the waste liquid discharged from the splash prevention cup 14 to the intermediate waste liquid storage section 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 waste liquid storage section 22. A valve 21a is provided midway along the recovery pipe 21. The valve 21a is electrically connected to the control section 130 and is normally closed. The opening and closing of the valve 21a is controlled by an operation command from the control section 130. When the valve 21a is opened by an operation command from the control section 130, the waste liquid collected in the splash prevention cup 14 passes through the recovery pipe 21 and is supplied to the intermediate waste liquid storage section 22.

[0046] The intermediate effluent storage section 22 is connected to the bubble generation section 24 via the effluent discharge pipe 23. The intermediate effluent storage section 22 can temporarily store the collected effluent. A filter 23a, a pump 23b, and a valve 23c are sequentially provided along the effluent discharge pipe 23 from upstream to downstream.

[0047] The filter 23a can remove impurities such as solids such as particles and metal ions contained in the effluent. When removing metal ions, for example, an ion exchange resin can be used as the filter 23a. The filter 23a may be omitted. The pump 23b is controlled by an operation command from the control unit 130, and can send the effluent stored in the intermediate effluent storage unit 22 to the bubble generation unit 24. The valve 23c is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 23c is controlled by an operation command from the control unit 130.

[0048] The bubble generating unit 24 has the function of mixing gas into the collected waste liquid and further generating minute bubbles of this gas. Specifically, as shown in Fig. 3, the bubble generating unit 24 at least includes a narrowed flow path section 24a, a gas supply pipe 24b, an open / close valve 24c, an enlarged flow path section 24d, and a two-phase mixture fluid supply pipe 24e as a supply pipe. Fig. 3 is a cross-sectional schematic diagram showing the general configuration of the bubble generating unit 24 according to this embodiment.

[0049] The narrowed flow path portion 24a is connected to the waste liquid discharge pipe 23 downstream of the waste liquid discharge pipe 23. The inner diameter of the narrowed flow path portion 24a is smaller than that of the waste liquid discharge pipe 23. As a result, the flow path of the narrowed flow path portion 24a is narrower than that of the waste liquid discharge pipe 23.

[0050] The gas supply pipe 24b is connected to the narrowed flow path portion 24a. The gas supply pipe 24b is also connected to a gas supply source (not shown). An on-off valve 24c is provided midway along the gas supply pipe 24b. The on-off valve 24c is electrically connected to the control unit 130 and is normally closed. The on-off of the on-off valve 24c is controlled by an operation command from the control unit 130. When the on-off valve 24c is opened by an operation command from the control unit 130, gas is supplied to the narrowed flow path portion 24a through the gas supply pipe 24b. The gas is not particularly limited, and examples thereof include nitrogen (N2) gas.

[0051] The expanded flow path section 24d is provided downstream of the narrowed flow path section 24a. A two-phase mixture fluid supply pipe 24e is connected to the downstream side of the expanded flow path section 24d. The expanded flow path section 24d has a tapered shape in which the inner diameter gradually increases toward the fluid outflow side (the direction of the arrow D in FIG. 3). Because the expanded flow path section 24d has such a tapered shape, tiny gas bubbles 202 are generated in the discharged fluid when the fluid flows from the narrowed flow path section 24a through the wider expanded flow path section 24d. As a result, a two-phase mixture fluid containing the bubbles 202 and the discharged fluid is generated in the expanded flow path section 24d. The organic solvent contained in the discharged fluid is adsorbed and present on the surfaces of the bubbles 202.

[0052] The two-phase mixture supply pipe 24e is connected at its downstream side to the swirl flow generating section 25. This allows the two-phase mixture generated in the bubble generating section 24 to be supplied to the swirl flow generating section 25.

[0053] The swirl flow generating section 25 has a function of generating a swirl flow in the wastewater containing minute bubbles 202, and separating the bubbles 202 and water by centrifugal separation. Specifically, as shown in Fig. 4, the swirl flow generating section 25 includes a storage tank 25a, an exhaust pipe 25b, a rotation drive section 25c, a chamber 25d, and an exhaust pipe 25e. Fig. 4 is an explanatory diagram showing a schematic configuration of the swirl flow generating section 25 in the recovery / reuse unit 2.

[0054] The rotational drive unit 25c rotates around axis B along the Z direction in response to an operation command from the control unit 130. The rotational drive unit 25c is mounted while holding the storage tank 25a, and is configured with a known belt, motor, and rotating shaft. As the rotational drive unit 25c rotates around axis B, the storage tank 25a held by the rotational drive unit 25c can also rotate around axis B. The chamber 25d can accommodate the storage tank 25a and the rotational drive unit 25c. The exhaust pipe 25b is provided at the top of the chamber 25d. The exhaust pipe 25b can exhaust gas generated from the swirling flow, including the vaporized gas of the organic solvent. In addition, a valve 25f is provided midway along the exhaust pipe 25b. The valve 25f is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 25f is controlled by an operation command from the control unit 130. When the valve 25f is opened in response to an operation command from the control unit 130, the gas containing the vaporized gas of the organic solvent is supplied to the condenser 201a (details of which will be described later). The discharge pipe 25e is provided at the bottom of the chamber 25d, and can discharge the waste liquid (water) remaining after the gas containing the vaporized gas of the organic solvent is separated.

[0055] In the swirl flow generating unit 25 shown in FIG. 4, by rotating the storage tank 25a, a swirl flow centered on axis B can be generated in the wastewater stored in the storage tank 25a. In the swirl flow, air bubbles 202, which have a low specific gravity, gather near the center of the storage tank 25a (at and around axis B), i.e., in the central portion 203 of the swirl flow. Furthermore, water, which has a higher specific gravity than the air bubbles 202, gathers in the outer portion 204 of the central portion 203 of the swirl flow. Therefore, larger air bubbles 202 made of gas are generated near the center of the storage tank 25a. Furthermore, organic solvents are adsorbed on the surfaces of the air bubbles 202. Therefore, by centrifuging the air bubbles 202 and water, the organic solvent contained in the wastewater can also be separated from the water. The rotation speed of the storage tank 25a can be set appropriately as needed.

[0056] The condensation section 201 includes a condenser 201a, a condensate discharge pipe 201b, and a separated liquid storage tank 201c that stores the condensate as a separated liquid. The condenser 201a is connected to the downstream end of the exhaust pipe 25b. The condenser 201a condenses the gas containing the vaporized gas of the organic solvent supplied from the exhaust pipe 25b. This liquefies at least the vaporized gas to obtain the organic solvent (condensate). The condenser 201a is connected to the exhaust pipe 25b downstream of the valve 25f. The condenser 201a is not particularly limited, and a known condenser can be used. The condensate discharge pipe 201b is connected to the condenser 201a at its upstream end and to the separated liquid storage tank 201c at its downstream end. The separated liquid storage tank 201c can temporarily store the organic solvent (condensate) discharged from the condenser 201a via the condensate discharge pipe 201b as a separated liquid. By providing the separated liquid storage tank 201c, even if it takes time to obtain a certain amount of organic solvent, the organic solvent can be stably supplied to the multiple valve 13b. Note that the separated liquid storage tank 201c may be omitted.

[0057] The upstream end of the separated liquid discharge pipe 28 is connected to the separated liquid storage tank 201c, and the other end is connected to the multiple valve 13b. This allows the organic solvent separated from the waste liquid to be supplied to the multiple valve 13b. A pump 28a and a flow rate control valve 28b are sequentially provided along the separated liquid discharge pipe 28 from the upstream side to the downstream side. The pump 28a is controlled by an operation command from the control unit 130, and can supply the organic solvent to the connection part 131 of the multiple valve 13b. The flow rate control valve 28b can adjust the flow rate of the organic solvent.

[0058] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus 100 of this embodiment will be described below. The substrate processing method according to this embodiment recovers a processing liquid containing an organic solvent that has been used to remove a rinse liquid composed of water, such as DIW, remaining on the surface Wf of the substrate W, and then separates and removes the water from the recovered processing liquid for reuse. This reduces the amount of organic solvent waste and reduces the environmental impact. More specifically, the substrate processing method according to this embodiment includes, in the recovery and reuse of the processing liquid after substrate processing, a draining process for draining the processing liquid after substrate processing, a separation process for recovering the drained liquid and separating the organic solvent from the drained liquid, and a supplying process for supplying the processing liquid containing at least the separated liquid (organic solvent) obtained in the separation process to the surface Wf of the substrate W.

[0059] The liquid draining step is a step of draining the processing liquid used in substrate processing on the front surface Wf of the substrate W from the substrate processing unit 1. In this step, first, when the valve 21a is opened in response to an operation command from the control unit 130, the processing liquid after substrate processing that has been collected in the splash prevention cup 14 is discharged as waste liquid through the recovery pipe 21 connected to the splash prevention cup 14. Furthermore, the waste liquid discharged through the recovery pipe 21 is stored in the intermediate waste liquid storage unit 22.

[0060] The separation step is a step of recovering the vaporized gas of the organic solvent from the recovered effluent to obtain the organic solvent. The separation step of this embodiment includes a bubble generation step of generating bubbles 202 in the effluent, a swirling flow generation step of generating a swirling flow in the effluent containing the bubbles 202, and a recovery step of recovering the vaporized gas of the organic solvent generated from the swirling flow.

[0061] The bubble generation process is a process in which gas is mixed into the wastewater after substrate processing and then tiny bubbles 202 of the gas are generated. In this process, first, the control unit 130 issues an operational command to open the valve 23c. Then, the pump 23b is activated, causing the wastewater stored in the intermediate wastewater storage unit 22 to flow through the wastewater discharge pipe 23 and be sent to the bubble generation unit 24. When the control unit 130 issues an operational command to open the on-off valve 24c, gas is supplied to the narrowed flow path portion 24a of the bubble generation unit 24 via the gas supply pipe 24b. When the wastewater mixed with the gas in the narrowed flow path portion 24a flows into the enlarged flow path portion 24d, tiny bubbles 202 are generated in the wastewater. This generates a two-phase mixture fluid containing tiny bubbles 202 in the wastewater. The amount of gas supplied to the wastewater is not particularly limited and can be set appropriately as needed.

[0062] The swirl flow generating step is a step of generating a swirl flow in a waste liquid (two-phase fluid mixture) containing minute bubbles 202, thereby separating the bubbles 202 and the organic solvent adsorbed on their surfaces from water. In this step, first, the two-phase fluid mixture containing the bubbles 202 generated by the bubble generation unit 24 is supplied to and stored in the storage tank 25a. Next, when a predetermined amount of the stored two-phase fluid mixture is reached, the control unit 130 issues an operation command to the valve 23c to close the valve. Furthermore, by rotating the rotation drive unit 25c about an axis B along the Z direction in response to an operation command from the control unit 130, the storage tank 25a held by the rotation drive unit 25c is also rotated about the axis B. This generates a swirl flow in the waste liquid containing the bubbles 202 stored in the storage tank 25a, and the bubbles 202 are collected near the center 203 of the storage tank 25a, generating larger bubbles 202. Furthermore, as the bubbles 202 gather in the center 203 of the swirling flow, the water contained in the discharged liquid gathers at the outer side 204 of the center 203 of the swirling flow. Here, since the organic solvent is adsorbed on the surfaces of the bubbles 202, the organic solvent and the water can be separated by centrifugal separation of the bubbles 202 and the water. The rotation speed of the storage tank 25a is not particularly limited as long as it does not cause the stored two-phase mixture fluid to overflow from the storage tank 25a, and can be set appropriately.

[0063] The recovery step is a step of recovering at least the bubbles 202 having the organic solvent adsorbed on their surfaces from the central portion 203 of the swirling flow. In this embodiment, the bubbles 202 that have gathered in the central portion 203 of the swirling flow become gas and are discharged through the exhaust pipe 25b. Because the organic solvent is also adsorbed on the surfaces of the bubbles 202, the vaporized gas of the organic solvent is also discharged through the exhaust pipe 25b. Furthermore, the gas containing the vaporized gas of the organic solvent is condensed in the condenser 201a of the condensation section 201 provided midway through the exhaust pipe 25b, thereby liquefying at least the vaporized gas and obtaining the organic solvent (condensation step). The obtained organic solvent is supplied to the separated liquid storage tank 201c through the condensate discharge pipe 201b and temporarily stored as the separated liquid. The waste liquid (water) remaining after the gas containing the vaporized organic solvent has been separated is discharged through the discharge pipe 25e.

[0064] The supplying step is a step of generating a processing liquid containing at least the organic solvent obtained in the recovering step and supplying the processing liquid to the surface Wf of the substrate W. In this step, a processing liquid is supplied to the surface Wf of the substrate W to replace the water used as a rinse liquid and to remove water remaining on the surface Wf of the substrate W. Specifically, the control unit 130 issues an operation command to open the flow rate adjustment valve 28b. As a result, the organic solvent stored in the separation liquid storage tank 201c is supplied to the multiple valve 13b via the separation liquid discharge pipe 28.

[0065] The concentration of the organic solvent contained in the processing liquid supplied to the substrate W may be adjusted by appropriately mixing the organic solvent supplied from the separation liquid storage tank 201c, the unused organic solvent supplied from the organic solvent supply unit 13d, and the unused water supplied from the water supply unit. In this case, the control unit 130 issues an operation command to the organic solvent supply unit 13d to independently open and close the upstream valve 133 while adjusting the flow rate with the flow rate control valve 28b. The control unit 130 also issues an operation command to the organic solvent supply unit 13d to open and close the valve 137 while adjusting the flow rate with the flow rate control valve 145.

[0066] As described above, in this embodiment, minute bubbles 202 with organic solvent adsorbed on their surfaces are generated in the wastewater, and these bubbles 202 are separated from the water by centrifugal separation using a swirling flow. Furthermore, by collecting the bubbles 202, the vaporized gas of the organic solvent adsorbed on the surfaces of the bubbles 202 is also collected at the same time, and the vaporized gas is condensed to obtain the organic solvent. This separation method can reduce the amount of organic solvent waste while suppressing increases in running costs, compared to conventional membrane separation methods using zeolite membranes or the like.

[0067] (Second embodiment) A second embodiment of the present invention will now be described.

[0068] [Substrate processing equipment] <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 (see FIG. 1), except for the recovery and reuse unit of the substrate processing section 110. Therefore, detailed descriptions of the indexer section 120, the control section 130, and the substrate processing units 1 of the substrate processing section 110 will be omitted and the same reference numerals will be used.

[0069] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 5. FIG. 5 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 3 in the substrate processing apparatus of this embodiment. In FIG. 5, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction. Furthermore, components having the same functions as those of the recovery / reuse unit 2 of the first embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0070] Similar to the recovery / reuse unit 2 of the first embodiment, the recovery / reuse unit 3 of the present embodiment recovers the processing liquid used to remove water remaining on the surface Wf of the substrate W, and separates the organic solvent from the recovered processing liquid to make it reusable. Specifically, as shown in FIG. 5 , the recovery / reuse unit 3 at least includes a separation section 30, a suction section 210 as a recovery section, and a separated liquid discharge pipe 28.

[0071] The separation section 30 includes at least a recovery pipe 21, an intermediate waste liquid storage section 22, a waste liquid discharge pipe 23, a bubble generation section 24, and a swirling flow generation section 25'. As shown in Fig. 6, the swirling flow generation section 25' differs from the swirling flow generation section 25 of the first embodiment in that it does not include an exhaust pipe 25b. Fig. 6 is an explanatory diagram showing a partial configuration of the swirling flow generation section 25' and the suction section 210 in the recovery / reuse unit 3.

[0072] The suction unit 210 can suction the organic solvent and air bubbles 202 in the central portion 203 of the swirling flow in the reservoir 25a. Specifically, the suction unit 210 includes a suction pipe 211, a suction pump 212, a valve 213, and a suction liquid reservoir 214, as shown in FIGS.

[0073] A suction port 211a is provided at the tip (one end) of the suction tube 211. The suction port 211a is preferably disposed inside the reservoir 25a, in the central portion 203 of the reservoir 25a (the region near axis B), near the bottom of the reservoir 25a. The other end of the suction tube 211 is connected to the aspirate reservoir 214. This allows the aspirate to be supplied to the aspirate reservoir 214. A suction pump 212 and a valve 213 are provided along the suction tube 211, sequentially from the upstream side. The suction pump 212 and the valve 213 are each electrically connected to the control unit 130. The suction pump 212 is controlled by an operation command from the control unit 130, and is capable of aspirating the organic solvent and air bubbles 202 from the reservoir 25a. The opening and closing of the valve 213 is controlled by an operation command from the control unit 130. When the valve 213 is opened in response to an operation command from the control unit 130, the aspirated liquid containing the organic solvent and the air bubbles 202 is supplied to the aspirated liquid reservoir 214. By providing the aspirated liquid reservoir 214, even when it takes time to separate a certain amount of organic solvent from the waste liquid, the organic solvent can be stably supplied to the multiple valve 13b.

[0074] In the recovery and reuse unit 3 of this embodiment, the suction pump 212, the valve 213, and the suction liquid storage tank 214 in the suction section 210 may be omitted, thereby simplifying the device configuration of the recovery and reuse unit 3. When such a device configuration is adopted, the pump 28a functions as a suction pump for sucking the organic solvent and the bubbles 202 from the storage tank 25a.

[0075] The recovery and reuse unit 3 of this embodiment may further include the condenser 201 of the first embodiment. In this case, the swirling flow generating unit is the swirling flow generating unit 25 of the first embodiment, which is equipped with the exhaust pipe 25b. The downstream end of the condensate discharge pipe 201b can be connected to the aspirated liquid storage tank 214, and the condensed liquid condensed in the condenser 201a can be stored in the aspirated liquid storage tank 214. By using the condenser 201 of the first embodiment in combination, it is possible to recover the vaporized gas of the organic solvent generated from the swirling flow of the wastewater. As a result, the organic solvent in the wastewater can be recovered more efficiently.

[0076] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus of this embodiment will be described below. The substrate processing method of this embodiment, in recovering and reusing the processing liquid after substrate processing, includes a draining step of draining the processing liquid after substrate processing, a separating step of recovering the drained liquid and separating the organic solvent from the drained liquid, and a supplying step of supplying the processing liquid containing at least the separated liquid (organic solvent) obtained in the separating step onto the surface Wf of the substrate W. In this embodiment, the draining step and the supplying step are the same as those in the first embodiment, and therefore will not be described below.

[0077] The separation step of this embodiment is a step of generating a swirling flow in the collected waste liquid, and obtaining the organic solvent by aspirating the bubbles 202 that gather in the center 203 of the swirling flow and the organic solvent concentrated in the center 203. The separation step of this embodiment includes a bubble generation step of generating bubbles 202 in the waste liquid, a swirling flow generation step of generating a swirling flow in the waste liquid containing the bubbles 202, and a recovery step of aspirating and recovering the organic solvent concentrated in the center 203 of the swirling flow.

[0078] The bubble generating step is the same as in the first embodiment, and therefore a detailed description thereof will be omitted.

[0079] The swirl flow generating step is a step of generating a swirl flow in waste liquid (two-phase fluid mixture) containing minute bubbles 202, thereby separating the bubbles 202 with the organic solvent adsorbed on the surface from water. In this step, first, the two-phase fluid mixture containing the bubbles 202 generated by the bubble generating unit 24 is supplied to and stored in the storage tank 25a. Next, when a predetermined amount of the stored two-phase fluid mixture is reached, the control unit 130 issues an operation command to the valve 23c to close the valve. Furthermore, by rotating the rotation drive unit 25c about an axis B along the Z direction in response to an operation command from the control unit 130, the storage tank 25a held by the rotation drive unit 25c is also rotated about the axis B. As a result, the waste liquid containing the bubbles 202 stored in the storage tank 25a is swirled by the swirl flow, and the bubbles 202 are collected near the center 203 of the storage tank 25a, generating larger bubbles 202. Furthermore, as the bubbles 202 gather in the central portion 203 of the swirling flow, the water contained in the discharged liquid gathers at the outer side 204 of the central portion 203 of the swirling flow. Here, since the organic solvent is adsorbed on the surfaces of the bubbles 202, the organic solvent and the water can be separated as a result of the centrifugation of the bubbles 202 and the water. As a result, the organic solvent is concentrated in the central portion 203 of the swirling flow. The rotation speed of the storage tank 25a is not particularly limited as long as it does not cause the stored two-phase mixture fluid to overflow from the storage tank 25a, and can be set appropriately.

[0080] The recovery step is a step of aspirating and recovering the organic solvent concentrated in the central portion 203 of the swirling flow. In this step, the control unit 130 first issues an operation command to the suction pump 212 to operate. It also issues an operation command to the valve 213 to open the valve. When the suction pump 212 operates, the air bubbles 202 that have collected in the central portion 203 of the swirling flow and the organic solvent concentrated in the central portion 203 are aspirated from the suction port 211a and supplied to the aspirated liquid storage tank 214 via the suction pipe 211. The aspirated organic solvent is temporarily stored in the aspirated liquid storage tank 214. The waste liquid (water) from which the organic solvent has been separated is discharged from the discharge pipe 25e.

[0081] As described above, in this embodiment, minute bubbles 202 having an organic solvent adsorbed on their surfaces are generated in the wastewater, and these bubbles 202 are separated from the water by centrifugal separation using a swirling flow. Furthermore, the bubbles 202 that gather in a central portion 203 of the swirling flow and the organic solvent concentrated in the central portion 203 are collected by suction, thereby separating the water from the water. This separation method can reduce the amount of organic solvent waste while suppressing an increase in running costs, compared to conventional membrane separation methods using a zeolite membrane or the like.

[0082] (Third embodiment) A third embodiment of the present invention will now be described.

[0083] [Substrate processing equipment] <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 embodiment (see FIG. 1), except for the recovery and reuse unit of the substrate processing section 110. Therefore, detailed descriptions of the indexer section 120, the control section 130, and the substrate processing units 1 of the substrate processing section 110 will be omitted and the same reference numerals will be used.

[0084] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 7. FIG. 7 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 4 in the substrate processing apparatus of this embodiment. In FIG. 7, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction. Furthermore, components having the same functions as those of the recovery / reuse unit 2 of the first embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0085] Similar to the recovery / reuse unit 2 of the first embodiment, the recovery / reuse unit 4 recovers the processing liquid used to remove water remaining on the surface Wf of the substrate W, and separates and removes the water from the recovered processing liquid to make it reusable. Specifically, as shown in FIG. 7 , the recovery / reuse unit 4 at least includes a separation section 40, a straight pipe section 221 as a recovery section, and a separated liquid discharge pipe 28.

[0086] The separation section 40 includes at least a recovery pipe 21 , an intermediate waste liquid storage section 22 , a waste liquid discharge pipe 23 , a bubble generating section 24 , and a swirling flow generating section 220 .

[0087] As shown in Fig. 8, the swirl flow generating section 220 is provided inside the two-phase mixture fluid supply pipe 24e of the bubble generation section 24. The swirl flow generating section 220 includes a blade support section 220a and a plurality of blade sections 220b (four in this embodiment) provided on the outer peripheral surface of the blade support section 220a. In this embodiment, the two-phase mixture fluid supply pipe 24e is preferably a straight pipe member. Fig. 8 is a cross-sectional schematic diagram showing the general configuration of the swirl flow generating section 220 and the straight pipe section 221.

[0088] The straight pipe portion 221 has a double pipe structure including an outer pipe 221a and an inner pipe 221b. The straight pipe portion 221 of this embodiment also includes an expanded diameter portion 221c, a discharge pipe 221d, and a closed portion 221e.

[0089] The outer pipe 221a is connected to the two-phase mixture fluid supply pipe 24e via the expanded diameter section 221c. The expanded diameter section 221c has a tapered shape in which the inner diameter gradually increases toward the outlet side of the swirling flow (the direction of the arrow indicated by E in FIG. 8). Because the expanded diameter section 221c has such a tapered shape, the organic solvent and bubbles 202 concentrated in the center of the swirling flow can be guided to the inner pipe 221b, and the water outside the center of the swirling flow can be guided to the gap α formed between the outer pipe 221a and the inner pipe 221b.

[0090] The upstream end of the inner pipe 221b is inserted from the downstream end of the outer pipe 221a. Meanwhile, the downstream end of the inner pipe 221b is connected to the separated liquid discharge pipe 28. The outer diameter of the inner pipe 221b is smaller than the inner diameter of the outer pipe 221a, thereby forming a gap α between the outer surface of the inner pipe 221b and the inner surface of the outer pipe 221a. A blocking portion 221e is provided in this gap α to block the gap α. The gap α is in communication with the discharge pipe 221d, allowing water to be discharged from the discharge pipe 221d.

[0091] In this embodiment, a storage tank for temporarily storing the separated organic solvent may be provided between the inner pipe 221b of the straight pipe portion 221 and the separated liquid discharge pipe 28. This allows the recovered organic solvent to be stably supplied to the multiple valve 13b even when it takes time to obtain a certain amount of organic solvent.

[0092] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus of this embodiment will be described below. The substrate processing method of this embodiment, in recovering and reusing the processing liquid after substrate processing, includes a draining step of draining the processing liquid after substrate processing, a separating step of recovering the drained liquid and separating the organic solvent from the drained liquid, and a supplying step of supplying the processing liquid containing at least the separated liquid (organic solvent) obtained in the separating step onto the surface Wf of the substrate W. In this embodiment, the draining step and the supplying step are the same as those in the first embodiment, and therefore will not be described below.

[0093] The separation process of this embodiment includes a bubble generation process of generating bubbles 202 in the wastewater, a swirling flow generation process of generating a swirling flow in the wastewater containing the bubbles 202, and a recovery process of flowing the organic solvent concentrated in the center of the swirling flow into the inner pipe 221b of the straight pipe section 221 having a double pipe structure, and flowing the separated water into the gap section α formed between the outer pipe 221a and the inner pipe 221b, thereby separating and recovering the organic solvent.

[0094] The bubble generating step is the same as in the first embodiment, and therefore a detailed description thereof will be omitted.

[0095] In the swirl flow generating step, first, a two-phase mixture containing bubbles 202 generated in the bubble generating unit 24 is supplied to the two-phase mixture supply pipe 24e. A swirl flow generating unit 220 is provided inside the two-phase mixture supply pipe 24e, and when the two-phase mixture flows through the swirl flow generating unit 220, the blades 220b rotate, thereby generating a swirling flow of the two-phase mixture. The swirling flow of the two-phase mixture flows in the direction indicated by arrow E while swirling around the pipe axis direction (the axial direction along the central axis F of the two-phase mixture supply pipe 24e). Therefore, the bubbles 202, which have a small specific gravity, are centrifuged and collected in the center of the swirling flow. On the other hand, water, which has a larger specific gravity than the bubbles 202, is collected outside the center of the swirling flow. Furthermore, because the organic solvent is adsorbed to the surfaces of the bubbles 202, the organic solvent also collects in the center of the swirling flow and is concentrated.

[0096] In the recovery process, when the swirling flow of the two-phase mixture fluid generated in the swirling flow generating process reaches the straight pipe section 221, the water separated outside the center of the swirling flow flows toward the gap α because the straight pipe section 221 is provided with the expanded diameter section 221c at its upstream end. Meanwhile, the air bubbles 202 and concentrated organic solvent in the center of the swirling flow flow through the inner pipe 221b. As a result, the two-phase mixture fluid is separated into the organic solvent and air bubbles 202, and water. The separated water is discharged from the discharge pipe 221d as a waste liquid. Meanwhile, the organic solvent and air bubbles 202 are supplied to the multiple valve 13b via the separated liquid discharge pipe 28, which is connected to the inner pipe 221b.

[0097] As described above, in this embodiment, minute bubbles 202 having an organic solvent adsorbed on their surfaces are generated in the wastewater, and a swirling flow is generated in the wastewater inside the two-phase mixture fluid supply pipe 24e. As a result, the organic solvent is concentrated in the center of the swirling flow, and the concentrated organic solvent is separated and recovered using the straight pipe section 221 having a double-pipe structure. This separation method can reduce the amount of organic solvent waste while suppressing an increase in running costs, compared to conventional membrane separation methods using a zeolite membrane or the like.

[0098] (Fourth embodiment) A fourth embodiment of the present invention will now be described.

[0099] [Substrate processing equipment] <Overall configuration of substrate processing apparatus and substrate processing unit> The substrate processing apparatus according to the fourth embodiment has basically the same configuration as the substrate processing apparatus 100 according to the first embodiment (see FIG. 1), except for the recovery and reuse unit of the substrate processing section 110. Therefore, detailed descriptions of the indexer section 120, the control section 130, and the substrate processing units 1 of the substrate processing section 110 will be omitted and the same reference numerals will be used.

[0100] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 9. FIG. 9 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 5 in the substrate processing apparatus of this embodiment. In FIG. 9, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction. Furthermore, components having the same functions as those of the recovery / reuse unit 2 of the first embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0101] 9, the recovery / reuse unit 5 of this embodiment, like the recovery / reuse unit 2 of the first embodiment, recovers the processing liquid used to remove water remaining on the surface Wf of the substrate W and separates the organic solvent from the recovered processing liquid to make it reusable. However, the recovery / reuse unit 5 of this embodiment differs from the recovery / reuse unit 2 of the first embodiment in that it uses a condensation section 201′ equipped with a condenser 201a and a condensed liquid discharge pipe 201b as a recovery section. The recovery / reuse unit 5 also differs in that it further includes a re-separation section 300. Note that in this embodiment, the condensation section 201 of the first embodiment, which further includes a separated liquid storage tank 201c, may be used as the condensation section.

[0102] The re-separation section 300 is provided at the downstream end of the condensate discharge pipe 201b and at the upstream end of the separated liquid discharge pipe 28, and has the function of further separating water contained in the separated liquid (organic solvent) that has been separated from the waste liquid in the separation section 20 and recovered as a condensate in the condensation section 201. Specific examples of the re-separation section 300 include the five modes described below.

[0103] 1. Re-separation unit according to the first aspect A first aspect of the re-separation section 300 is a first re-separation section 310 including a separation liquid storage section 311, a first irradiation section 312, a circulation path 313, and a separation membrane section 314, as shown in Fig. 10. Fig. 10 is an explanatory diagram showing a schematic configuration of the first re-separation section 310.

[0104] The separated liquid storage unit 311 includes a storage tank 311a and an exhaust pipe 311b provided above the storage tank 311a. The storage tank 311a can store the condensed liquid (separated liquid) supplied from the condenser 201a via the condensed liquid discharge pipe 201b. The exhaust pipe 311b can discharge water vapor generated by evaporation of water contained in the stored condensed liquid to the outside of the separated liquid storage unit 311.

[0105] The first irradiating unit 312 irradiates the condensate stored in the separated liquid storage unit 311 with first light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water. In this way, the first irradiating unit 312 functions as a gas-liquid separating unit that vaporizes the water contained in the condensate and separates it from the organic solvent. The first irradiating unit 312 is disposed, for example, above the separated liquid storage unit 311, so that the first light can be irradiated from above onto the condensate stored in the separated liquid storage unit 311.

[0106] Specifically, the first irradiation unit 312 includes, for example, a housing and a light source accommodated in the housing. The light source can irradiate first light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water. The first light is not absorbed by the organic solvent and passes through, so it can reach the inside of the separated liquid storage unit 311. As a result, the water in the condensate can be efficiently heated and vaporized. By vaporizing the water (i.e., by changing its state to water vapor and decreasing its density), it is separated from the organic solvent in the condensate. The absorption wavelength band of the organic solvent is set appropriately depending on the type of organic solvent. For example, when the organic solvent is IPA, the wavelength range that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water is 1200 cm -1 The areas are as follows:

[0107] The circulation path 313 is sequentially provided, from upstream to downstream, with a pump 313a, a filter 313b, and a separation membrane unit 314. The pump 313a is controlled by operational commands from the control unit 130, and can send the organic solvent separated from the condensate in the separated liquid storage unit 311 to the circulation path 313. The filter 313b can remove impurities such as metal ions contained in the organic solvent. To remove metal ions, for example, an ion exchange resin can be used as the filter 313b. A three-way valve 313c is provided at the branch point where the separated liquid discharge pipe 28 branches off from the circulation path 313. By providing the three-way valve 313c at the branch point, the flow path of the separated liquid flowing through the circulation path 313 can be changed to the separated liquid discharge pipe 28. The three-way valve 313c is electrically connected to the control unit 130, and the change in flow path by the three-way valve 313c is controlled by operational commands from the control unit 130.

[0108] The separation membrane section 314 can further separate water from the separated liquid (organic solvent) discharged from the separated liquid storage section 311. By providing the separation membrane section 314, the water removal rate can be further improved. An example of a separation membrane used in the separation membrane section 314 is a dehydration membrane that is permeable to water but not to organic solvents such as IPA. The separation membrane may be a polymer membrane made of a polymer material, an inorganic membrane made of an inorganic material, or other membranes. A specific example of a separation membrane is a zeolite membrane made of zeolite. A water discharge pipe 314a that discharges water separated from the waste liquid is connected to the separation membrane section 314.

[0109] In the first re-separation section 310 of this embodiment, the circulation path 313 and the separation membrane section 314 may be omitted.

[0110] 2. Re-separation unit according to the second aspect A second aspect of the re-separation section 300 is a second re-separation section 320, as shown in Fig. 11, which includes a separated liquid storage section 321, a heat pipe as a gas-liquid separation section, a circulation path 313, and a separation membrane section 314. Fig. 11 is an explanatory diagram showing a schematic configuration of the second re-separation section 320.

[0111] As shown in FIG. 12, the separated liquid storage unit 321 includes a storage tank 321a, an organic solvent recovery unit 321b for recovering the organic solvent, and a water discharge pipe 321f for discharging water separated from the condensate. FIG. 12 is a schematic diagram illustrating the separated liquid storage unit 321 and the heat pipe 322. The storage tank 321a can store the condensate (separated liquid) supplied from the condenser 201a via the condensate discharge pipe 201b. The organic solvent recovery unit 321b is provided above the liquid level of the condensate stored in the storage tank 321a and has an annular recovery unit 321c and an opening 321d. The annular recovery unit 321c is provided so as to extend in an annular shape from the inner wall of the storage tank 321a toward the center. The opening 321d is provided in the center of the annular recovery unit 321c and is formed by an annular wall 321e standing in a direction approximately perpendicular to the annular recovery unit 321c. The provision of annular wall 321e prevents the liquid organic solvent from flowing down into the condensate stored in storage tank 321a. Furthermore, the provision of opening 321d in the center of annular recovery unit 321c allows the vaporized organic solvent gas to rise to annular cooling unit 322b (first cooling unit, described in detail later). Water discharge pipe 321f can discharge water separated from the condensate by vaporizing the organic solvent from storage tank 321a to the outside.

[0112] In the storage tank 321a, the connection position of the condensate discharge pipe 201b is disposed below the position where the organic solvent recovery unit 321b is provided. In addition, the storage tank 321a is connected to a circulation path 313 so that the organic solvent recovered from the condensate and stored in the organic solvent recovery unit 321b is discharged to the circulation path 313 and the organic solvent circulated through the circulation path 313 returns to the organic solvent recovery unit 321b.

[0113] As shown in FIG. 12, the heat pipe 322 includes a heating element 322a and an annular cooling element 322b. The heating element 322a is thermally connected to the storage tank 321a and heats the condensate stored in the storage tank 321a by radiating heat. The heating element 322a heats the condensate to a temperature equal to or higher than the boiling point of the organic solvent but lower than the boiling point of water, thereby vaporizing only the organic solvent and separating it from the condensate. The annular cooling element 322b absorbs heat (receives heat) from the organic solvent that has been vaporized by the heating element 322a and has risen through the opening 321d, thereby cooling it. The annular cooling element 322b can convert the vaporized organic solvent into a liquid state by cooling it to a temperature lower than the liquefaction temperature of the organic solvent. The annular cooling element 322b is arranged annularly around the central axis of the storage tank 321a. Furthermore, the inner diameter of the annular cooling unit 322b is larger than the diameter of the opening 321d of the organic solvent recovery unit 321b, which ensures that the liquid organic solvent is collected in the annular recovery unit 321c and prevents it from dropping into the condensate through the opening 321d.

[0114] In the second re-separation section 320 of this embodiment, the circulation path 313 and the separation membrane section 314 may be omitted.

[0115] 3. Re-separation unit according to the third aspect A third aspect of the re-separation section 300 is a third re-separation section 330, as shown in Figures 11 and 13, which includes a separated liquid storage section 331, a second irradiation section 332 as a gas-liquid separation section, a circular cooling section 333 as a first cooling section, a condensed liquid cooling section 334 as a second cooling section, a circulation path 313, and a separation membrane section 314.

[0116] As shown in FIG. 13, the separated liquid storage unit 331 includes a storage tank 321a, an organic solvent recovery unit 321b for recovering the organic solvent, and a water discharge pipe 321f for discharging water separated from the condensate. FIG. 13 is an explanatory diagram schematically showing the separated liquid storage unit 331, the second irradiation unit 332, the annular cooling unit 333, and the condensate cooling unit 334. The storage tank 321a can store the condensate (separated liquid) supplied from the condenser 201a via the condensate discharge pipe 201b. The organic solvent recovery unit 321b is provided above the liquid level of the condensate stored in the storage tank 321a and includes an annular recovery unit 321c and an opening 321d. The annular recovery unit 321c is provided so as to extend annularly from the inner wall of the storage tank 321a toward the center. Opening 321d is provided in the center of annular collection unit 321c and is formed by erecting annular wall 321e in a direction approximately perpendicular to annular collection unit 321c. Providing annular wall 321e prevents the liquid organic solvent from flowing down into the condensate stored in storage tank 321a. Furthermore, providing opening 321d in the center of annular collection unit 321c allows the vaporized organic solvent gas to rise to annular cooling unit 333 (details will be described later). Water discharge pipe 321f can discharge water separated from the condensate by vaporizing the organic solvent from storage tank 321a to the outside.

[0117] The second irradiator 332 irradiates the condensate stored in the storage tank 321a with second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent. In this way, the second irradiator 332 functions as a gas-liquid separator that vaporizes the organic solvent contained in the condensate and separates it from the condensate. For example, if the storage tank 321a is transparent to the second light, the second irradiator 332 can be disposed on the side of the storage tank 321a to irradiate the condensate stored in the storage tank 321a with the second light.

[0118] The position where second irradiator 332 is disposed is not particularly limited as long as it is a position where the second light can be irradiated onto the condensate stored in storage tank 321a. For example, second irradiator 332 may be disposed inside storage tank 321a. In this way, even if storage tank 321a is not transparent to the second light, the condensate stored in storage tank 321a can be irradiated with the second light.

[0119] Specifically, the second irradiation unit 332 includes, for example, a housing and a light source accommodated in the housing. The light source can irradiate second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent. The second light is not absorbed by water and passes through, so it can reach the inside of the storage tank 321a. As a result, the organic solvent in the condensate can be efficiently heated and vaporized. The organic solvent is separated from water in the condensate by vaporization. The absorption wavelength band of the organic solvent is set appropriately depending on the type of organic solvent. For example, when the organic solvent is IPA, the wavelength range that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent is 1200 cm -1 It will be an area that exceeds this.

[0120] The annular cooling unit 333 cools the organic solvent that has evaporated from the condensate and rises through the opening 321d. The annular cooling unit 333 can convert the organic solvent vapor to a liquid state by cooling it to a temperature below the liquefaction temperature of the organic solvent. The annular cooling unit 333 is annularly disposed about the central axis of the storage tank 321a. The annular cooling unit 333 is also formed so that its inner diameter is larger than the opening diameter of the opening 321d of the organic solvent recovery unit 321b. This ensures that the liquid organic solvent is reliably collected by the annular recovery unit 321c and prevents it from falling into the condensate through the opening 321d.

[0121] The condensate cooling unit 334 functions as a solid-liquid separation unit by cooling the condensate stored in the storage tank 321a to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice 335. A known device can be used as the condensate cooling unit 334, and specific examples include a Peltier element.

[0122] In the third re-separation section 330 of this embodiment, the circulation path 313 and the separation membrane section 314 may be omitted.

[0123] 4. Re-separation unit according to the fourth aspect A fourth aspect of the re-separation section 300 is a fourth re-separation section 340, as shown in Fig. 14, which includes a separated liquid storage section 341, a separated liquid cooling section 342 as a second cooling section, and a removal section 343. Fig. 14 is an explanatory diagram showing a schematic configuration of the fourth re-separation section 340.

[0124] The separated liquid storage section 341 can store the condensed liquid (separated liquid) supplied from the condenser 201a via the condensed liquid discharge pipe 201b.

[0125] The separated liquid cooling section 342 functions as a solid-liquid separation section by cooling the condensed liquid stored in the separated liquid storage section 341 to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice. As the separated liquid cooling section 342, a known device can be used, and specific examples include a Peltier element.

[0126] The removal unit 343 includes at least a circulation path 343a, a pump 343b, a filter 343c, and a valve 343d. The pump 343b, the filter 343c, and the valve 343d are sequentially arranged along the circulation path 343a from upstream to downstream. The pump 343b is controlled by operational commands from the control unit 130 and can send the organic solvent, which has been solidified and separated into solid and liquid in the separated liquid storage unit 341, to the circulation path 343a. The filter 343c can separate and remove ice contained in the organic solvent. The valve 343d is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 343d is controlled by operational commands from the control unit 130. The circulation path 343a, upstream of the filter 343c, may be cooled by a known cooling means.

[0127] 5. Re-separation unit according to the fifth aspect A fifth aspect of the re-separation section 300 is the aforementioned separation membrane section 314. That is, by providing the separation membrane section 314 at the downstream end of the condensate discharge pipe 201b and the upstream end of the separated liquid discharge pipe 28, it is possible to further separate water contained in the condensate (organic solvent) recovered as the separated liquid. Note that the separation membrane section 314 is as described above, and therefore a detailed description thereof will be omitted.

[0128] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus of this embodiment will be described below. The substrate processing method of this embodiment, in recovering and reusing the processing liquid after substrate processing, includes a draining step of draining the processing liquid after substrate processing, a separation step of recovering the drained liquid and removing at least a portion of the water from the drained liquid, and a supplying step of supplying the processing liquid containing at least the separated liquid (organic solvent) obtained in the separation step to the surface Wf of the substrate W. However, the substrate processing method of this embodiment differs from the substrate processing method of the first embodiment in that the separation step includes a re-separation step for further separating water from the condensed liquid obtained in the recovery step. Therefore, the following describes the re-separation step, and detailed descriptions of the other steps are omitted.

[0129] The re-separation step is a step in which water is further separated and removed from the condensate recovered by the condenser 201a to obtain a more pure organic solvent (separated liquid). The re-separation step is performed using any one of the first to fifth aspects of the re-separation section 300 described above. The re-separation step of this embodiment will be described below for each aspect.

[0130] 1. Re-separation step according to the first embodiment The re-separation step according to the first embodiment is carried out using a first re-separation section 310 shown in FIG.

[0131] First, the condensed liquid condensed by the condenser 201a flows through the condensate discharge pipe 201b and is stored in the storage tank 311a of the separated liquid storage unit 311 (storage process). When a predetermined amount of condensed liquid has been stored in the storage tank 311a, the control unit 130 issues an operational command to close the valve 25f. Furthermore, in response to an operational command from the control unit 130, the first irradiation unit 312 irradiates the condensed liquid stored in the storage tank 311a with the first light (gas-liquid separation process, first irradiation process). As described above, the wavelength range of the first light does not include the absorption wavelength band of organic solvents, but includes the absorption wavelength band of water. Therefore, only the water contained in the condensed liquid evaporates and becomes water vapor. Only the separated liquid (organic solvent) is stored in the storage tank 311a. The irradiation amount of the first light can be set appropriately as needed. The water vapor is exhausted from the exhaust pipe 311b. Furthermore, the degree of water evaporation can be controlled by adjusting the irradiation amount of the first light. For example, increasing the irradiation amount of the first light can promote evaporation of water contained in the condensate and increase the amount of water vapor.

[0132] Furthermore, in the re-separation step, water is removed from the separated liquid (organic solvent) separated from the condensate using a separation membrane unit 314. Specifically, the organic solvent irradiated by the first irradiation unit 312 is circulated through a circulation path 313 by operating a pump 313a. Impurities such as metal ions are removed from the organic solvent flowing through the circulation path 313 by a filter 313b installed midway along the circulation path 313, and then the water contained in the organic solvent is further separated and removed by a separation membrane unit 314. The separated water is discharged through a water discharge pipe 314a. The concentration of the organic solvent from which the impurities and water have been removed is measured, for example, using a concentration meter (not shown). Furthermore, the measured value of the organic solvent concentration is input to the control unit 130. If the measured value is determined to have reached a predetermined value, the control unit 130 issues an operational command to the three-way valve 313c to change the flow path to the separated liquid discharge pipe 28. As a result, the organic solvent is supplied to the multiple valve 13b via the separated liquid discharge pipe 28. On the other hand, if it is determined that the measured value of the concentration of the organic solvent has not reached the predetermined value, no operation command to change the flow path is sent to the three-way valve 313c, and the organic solvent is returned to the reservoir tank 311a via the circulation path 313. The circulation of the organic solvent in the circulation path 313 continues until the measured value of the concentration of the organic solvent by the concentration meter reaches the predetermined value.

[0133] As described above, in the substrate processing method including the re-separation step according to the first embodiment, first, bubbles 202 having the organic solvent adsorbed on their surfaces are separated from water by centrifugal separation using a swirling flow, and a gas containing the evaporated organic solvent is recovered. The condensate obtained by condensing this gas is then irradiated with light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water, thereby vaporizing and separating only the water contained in the condensate. This separation method allows for more efficient separation and recovery of the organic solvent while suppressing increases in running costs compared to conventional membrane separation methods using zeolite membranes, etc., and can reduce the amount of organic solvent waste.

[0134] 2. Re-separation step according to the second embodiment The re-separation step according to the second embodiment is carried out using a second re-separation section 320 shown in FIGS.

[0135] First, the condensed liquid condensed by the condenser 201a flows through the condensate discharge pipe 201b and is stored in the storage tank 321a of the separated liquid storage unit 321 (storage step). When a predetermined amount of condensed liquid has been stored in the storage tank 321a, the control unit 130 issues an operation command to the valve 25f to close it. Furthermore, in response to an operation command from the control unit 130, the heating unit 322a of the heat pipe 322 heats the condensed liquid stored in the storage tank 321a (gas-liquid separation step, heating step). The heating temperature of the heating unit 322a is equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water. Therefore, only the organic solvent contained in the condensed liquid vaporizes. The vaporized organic solvent rises through the opening 321d of the organic solvent recovery unit 321b and comes into contact with the annular cooling unit 322b, where it is cooled and becomes a liquid (gas-liquid separation step, first cooling step). The organic solvent in a liquid state (separated liquid) does not fall into the condensed liquid but is collected in the annular collection section 321c.

[0136] Furthermore, in the re-separation step, water is removed from the organic solvent separated from the condensate using a separation membrane unit 314. Specifically, the organic solvent collected in the annular recovery unit 321c is circulated through the circulation path 313 by operating the pump 313a. Impurities such as metal ions are removed from the organic solvent flowing through the circulation path 313 by a filter 313b installed midway along the circulation path 313, and then the water contained in the organic solvent is separated and removed by the separation membrane unit 314. The separated water is discharged through a water discharge pipe 314a. The concentration of the organic solvent from which the impurities and water have been removed is measured, for example, using a concentration meter (not shown). Furthermore, the measured value of the organic solvent concentration is input to the control unit 130. If the measured value is determined to have reached a predetermined value, the control unit 130 issues an operational command to the three-way valve 313c to change the flow path to the separated liquid discharge pipe 28. As a result, the organic solvent is supplied to the multiple valve 13b via the separated liquid discharge pipe 28. On the other hand, if it is determined that the measured value of the organic solvent concentration has not reached the predetermined value, no command is issued to the three-way valve 313c to change the flow path, and the organic solvent is returned to the annular recovery unit 321c of the organic solvent recovery unit 321b via the circulation path 313. The circulation of the organic solvent through the circulation path 313 continues until the measured value of the organic solvent concentration by the concentration meter reaches a predetermined value. The organic solvent obtained by further separating water in the re-separation step can be reused as a treatment liquid in the supply step, as in the first embodiment.

[0137] As described above, in the substrate processing method including the re-separation step according to the second embodiment, first, bubbles 202 having the organic solvent adsorbed on their surfaces are separated from water by centrifugal separation using a swirling flow, and a gas containing the vaporized organic solvent is recovered. The gas is then condensed to obtain a condensate, which is heated within a temperature range equal to or higher than the boiling point of the organic solvent but lower than the boiling point of water, thereby vaporizing and separating only the organic solvent contained in the condensate. This separation method allows for more efficient separation and recovery of the organic solvent while suppressing increases in running costs, compared to conventional membrane separation methods using zeolite membranes or the like, and reduces the amount of organic solvent waste.

[0138] 3. Re-separation step according to the third embodiment The re-separation step according to the third embodiment is carried out using a third re-separation section 330 shown in FIGS.

[0139] First, the condensate condensed by the condenser 201a flows through the condensate discharge pipe 201b and is stored in the storage tank 321a of the separated liquid storage unit 321 (storage step). When a predetermined amount of condensate has been stored in the storage tank 321a, the control unit 130 issues an operational command to the valve 25f to close it. Furthermore, in response to an operational command from the control unit 130, the condensate cooling unit 334 cools the condensate stored in the storage tank 321a (solid-liquid separation step, second cooling step). As described above, the cooling temperature of the condensate cooling unit 334 is higher than the freezing point of the organic solvent and lower than the freezing point of water. Therefore, only the water contained in the condensate solidifies, forming ice 335. This allows solid-liquid separation of the organic solvent and water to proceed in the condensate.

[0140] In the re-separation step, the control unit 130 issues an operational command to the second irradiation unit 332, which irradiates the condensate stored in the storage tank 321a with the second light (gas-liquid separation step, second irradiation step). As described above, the wavelength range of the second light excludes the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent. Therefore, only the organic solvent contained in the condensate vaporizes and evaporates. The vaporized organic solvent rises through the opening 321d of the organic solvent recovery unit 321b and is cooled by contacting the annular cooling unit 333 (gas-liquid separation step, first cooling step). The cooling temperature of the annular cooling unit 333 is below the liquefaction temperature of the organic solvent. As a result, the organic solvent vapor becomes liquid and is collected in the annular recovery unit 321c without falling into the condensate. Only water, or water and ice 335, is stored in the storage tank 321a. Furthermore, the water remaining in the storage tank 321a is discharged through the water discharge pipe 321f. Furthermore, the ice 335 remaining in the storage tank 321a is thawed naturally or heated to turn into water, and then discharged through the water discharge pipe 321f. The irradiation amount of the second light can be set appropriately as needed. The water is discharged through the water discharge pipe 321f. Furthermore, the degree of evaporation of the organic solvent can be controlled by adjusting the irradiation amount of the second light. For example, increasing the irradiation amount of the second light can promote evaporation of the organic solvent contained in the condensate, thereby increasing the amount of organic solvent vapor. The organic solvent obtained by further separating water in the re-separation step can be reused as a treatment liquid in the supply step, as in the first embodiment.

[0141] As described above, in the substrate processing method including the re-separation step according to the third embodiment, first, bubbles 202 having the organic solvent adsorbed on their surfaces are separated from water by centrifugal separation using a swirling flow, and a gas containing the vaporized organic solvent is recovered. The gas is then condensed, and the condensate is cooled to solidify the water for solid-liquid separation, and the organic solvent in the condensate is vaporized for gas-liquid separation. This separation method allows for more efficient separation and recovery of the organic solvent while suppressing increases in running costs, compared to conventional membrane separation methods using zeolite membranes or the like, and reduces the amount of organic solvent waste.

[0142] 4. Re-separation step according to the fourth embodiment The re-separation step according to the fourth embodiment is carried out using a fourth re-separation section 340 shown in FIG.

[0143] First, the condensed liquid condensed by the condenser 201a flows through the condensed liquid discharge pipe 201b and is stored in the separated liquid storage section 341 (storing step). When a predetermined amount of condensed liquid has been stored in the separated liquid storage section 341, the control section 130 issues an operational command to close the valve 25f. Furthermore, in response to an operational command from the control section 130, the separated liquid cooling section 342 cools the condensed liquid stored in the separated liquid storage section 341 (solid-liquid separation step, second cooling step). As described above, the cooling temperature of the separated liquid cooling section 342 is higher than the freezing point of the organic solvent and lower than the freezing point of water. Therefore, only the water contained in the condensed liquid solidifies to form ice. This allows solid-liquid separation of the organic solvent and water to proceed in the condensed liquid.

[0144] Subsequently, after ice is generated, valve 343d is opened by an operation command from control unit 130, and pump 343b is activated to circulate the condensate containing ice through circulation path 343a. Since filter 343c, which enables ice removal, is provided midway along circulation path 343a, the ice in the condensate is removed by filter 343c, and only the separated liquid (organic solvent) returns to separated liquid storage unit 341. The concentration of the separated liquid from which the ice has been removed is measured, for example, by a concentration meter (not shown). Furthermore, the measured value of the organic solvent concentration is input to control unit 130. If the measured value reaches a predetermined value, control unit 130 closes valve 343d by an operation command and stops pump 343b. On the other hand, if the measured value of the organic solvent concentration does not reach the predetermined value, the circulation of the separated liquid through circulation path 343a continues until the organic solvent concentration measured by the concentration meter reaches the predetermined value. The organic solvent obtained by further separating water in the re-separation step can be reused as a treatment liquid in the supply step in the same manner as in the first embodiment.

[0145] As described above, in the substrate processing method including the re-separation step according to the fourth embodiment, first, bubbles 202 having the organic solvent adsorbed on their surfaces are separated from water by centrifugal separation using a swirling flow, and a gas containing the evaporated organic solvent is recovered. The gas is then condensed, and the condensate is cooled to solidify the water contained in the condensate, thereby performing solid-liquid separation. The ice is then removed using filter 343c, and the organic solvent in the condensate is separated and recovered. This separation method can reduce the amount of organic solvent waste while suppressing increases in running costs, compared to conventional membrane separation methods using zeolite membranes or the like.

[0146] 5. Re-separation step according to the fifth embodiment The re-separation step according to the fifth embodiment is carried out using the separation membrane part 314.

[0147] That is, the condensed liquid condensed by the condenser 201a is supplied to the separation membrane section 314 via the condensed liquid discharge pipe 201b, where water contained in the condensed liquid is further separated and removed. The separated water is discharged from the water discharge pipe 314a. As a result, the organic solvent obtained by further separating water from the condensed liquid can be reused as a treatment liquid in the supply step, similar to the first embodiment.

[0148] As described above, in the substrate processing method including the re-separation step according to the fifth embodiment, first, bubbles 202 having the organic solvent adsorbed on their surfaces are separated from water by centrifugal separation using a swirling flow, and a gas containing the evaporated organic solvent is recovered. Furthermore, the gas is condensed, and the condensate is further separated from the water using separation membrane unit 314, thereby separating and recovering the organic solvent in the wastewater. This separation method allows for more efficient separation and recovery of the organic solvent than conventional membrane separation methods using, for example, a zeolite membrane, and reduces the amount of organic solvent waste.

[0149] (Fifth embodiment) A fifth embodiment of the present invention will now be described.

[0150] [Substrate processing equipment] <Overall configuration of substrate processing apparatus and substrate processing unit> The substrate processing apparatus according to the fifth embodiment has basically the same configuration as the substrate processing apparatus 100 according to the second embodiment (see FIG. 1), except for the recovery and reuse unit of the substrate processing section 110. Therefore, detailed descriptions of the indexer section 120, the control section 130, and the substrate processing units 1 of the substrate processing section 110 will be omitted and the same reference numerals will be used.

[0151] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing apparatus 110 will be described below with reference to FIG. 15. FIG. 15 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 6 in the substrate processing apparatus of this embodiment. In FIG. 15, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. In this figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction. Furthermore, components having the same functions as those of the recovery / reuse unit 3 of the second embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0152] 15, the recovery / reuse unit 6 of this embodiment, like the recovery / reuse unit 3 of the second embodiment, recovers the processing liquid used to remove water remaining on the surface Wf of the substrate W, and separates the organic solvent from the recovered processing liquid to make it reusable. However, the recovery / reuse unit 6 of this embodiment differs from the recovery / reuse unit 3 of the second embodiment in that it uses a suction part 210' including a suction pipe 211, a suction pump 212, and a valve 213 as a recovery part. The recovery / reuse unit 6 also differs in that it further includes the re-separation part 300 of the fourth embodiment.

[0153] As in the fourth embodiment, the re-separation unit 300 is composed of any one of the first re-separation unit 310, second re-separation unit 320, third re-separation unit 330, fourth re-separation unit 340, or separation membrane unit 314 (hereinafter, sometimes referred to as the "first re-separation unit 310, etc."). As shown in FIG. 15, the re-separation unit 300 is provided at the downstream end of the suction pipe 211 of the suction unit 210' and at the upstream end of the separated liquid discharge pipe 28. More specifically, for example, when the re-separation unit 300 is the first re-separation unit 310 according to the first aspect, the storage tank 311a is connected to the suction pipe 211, and the suction liquid (separated liquid) suctioned by the suction unit 210' is stored in the storage tank 311a (see FIG. 10). Furthermore, when the re-separation section 300 is the second re-separation section 320 according to the second embodiment or the third re-separation section 330 according to the third embodiment, the storage tank 321a is connected to the suction pipe 211, and the aspirated liquid (separated liquid) aspirated by the suction section 210′ ​​is stored in the storage tank 321a (see FIGS. 11, 12, and 13). Furthermore, when the re-separation section 300 is the fourth re-separation section 340 according to the fourth embodiment, the separation liquid storage section 341 is connected to the suction pipe 211, and the separation liquid storage section 341 stores the aspirated liquid (separated liquid) aspirated by the suction section 210′ ​​(see FIG. 14). Furthermore, when the re-separation section 300 is a separation membrane section 314 relating to the fifth embodiment, the separation membrane section 314 is the downstream end of the suction pipe 211 and is connected to the upstream end of the separation liquid discharge pipe 28, and the separation liquid separated by the separation membrane section 314 is stored in the separation liquid storage section 341.

[0154] In this embodiment, the suction part 210 of the second embodiment further including the suction liquid reservoir 214 may be used in place of the suction part 210'.

[0155] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus of this embodiment will be described below. The substrate processing method of this embodiment, in recovering and reusing the processing liquid after substrate processing, includes a draining process of draining the processing liquid after substrate processing, a separation process of recovering the drained liquid and removing at least a portion of the water from the drained liquid, and a supplying process of supplying the processing liquid obtained in the separation process, which contains at least a separated liquid (organic solvent), to the surface Wf of the substrate W. However, the substrate processing method of this embodiment differs from the substrate processing method of the second embodiment in that the separation process includes a re-separation process for further separating water from the condensed liquid obtained in the recovery process. This re-separation process is performed by one of the first re-separation units 310, etc. Details of the re-separation process performed by one of these units are the same as those described in the fourth embodiment. Therefore, detailed description thereof will be omitted.

[0156] (Sixth embodiment) A sixth embodiment of the present invention will be described below.

[0157] [Substrate processing equipment] <Overall configuration of substrate processing apparatus and substrate processing unit> The substrate processing apparatus according to the sixth embodiment has basically the same configuration as the substrate processing apparatus 100 according to the third embodiment (see FIG. 1), except for the recovery and reuse unit of the substrate processing section 110. Therefore, detailed descriptions of the indexer section 120, the control section 130, and the substrate processing units 1 of the substrate processing section 110 will be omitted and the same reference numerals will be used.

[0158] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing apparatus 110 will be described below with reference to FIG. 16. FIG. 16 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 7 in the substrate processing apparatus of this embodiment. In FIG. 16, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationship of the illustrated objects. In this figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction. Furthermore, components having the same functions as those of the recovery / reuse unit 4 of the third embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0159] 16, the recovery / reuse unit 7 of the present embodiment, like the recovery / reuse unit 4 of the third embodiment, recovers the processing liquid used to remove water remaining on the surface Wf of the substrate W, and separates the organic solvent from the recovered processing liquid to make it reusable. However, the recovery / reuse unit 7 of the present embodiment differs from the recovery / reuse unit 4 of the third embodiment in that it further includes the re-separation section 300 of the fourth embodiment.

[0160] As in the fourth embodiment, the re-separation section 300 is configured as one of the first re-separation sections 310, etc. As shown in Fig. 16, the re-separation section 300 is provided at the downstream end of the straight pipe section 221 and at the upstream end of the separated liquid discharge pipe 28. More specifically, for example, when the re-separation section 300 is the first re-separation section 310 according to the first aspect, the storage tank 311a is connected to the inner pipe 221b of the straight pipe section 221, and the separated liquid separated by the straight pipe section 221 is stored in the storage tank 311a (see Fig. 10). Furthermore, when the re-separation section 300 is the second re-separation section 320 according to the second embodiment or the third re-separation section 330 according to the third embodiment, the storage tank 321a is connected to the inner pipe 221b of the straight pipe section 221, and the separated liquid separated by the straight pipe section 221 is stored in the storage tank 321a (see FIGS. 11, 12, and 13). Furthermore, when the re-separation section 300 is the fourth re-separation section 340 according to the fourth embodiment, the separated liquid storage section 341 is connected to the inner pipe 221b of the straight pipe section 221, and the separated liquid separated by the straight pipe section 221 is stored in the separated liquid storage section 341 (see FIG. 14). Furthermore, when the re-separation section 300 is a separation membrane section 314 relating to the fifth embodiment, the separation membrane section 314 is the downstream end of the suction pipe 211 and is connected to the upstream end of the separation liquid discharge pipe 28, and the separation liquid separated by the separation membrane section 314 is stored in the separation liquid storage section 341.

[0161] [Substrate processing method] Next, a substrate processing method using the substrate processing apparatus of this embodiment will be described below. The substrate processing method of this embodiment, in recovering and reusing the processing liquid after substrate processing, includes a draining process of draining the processing liquid after substrate processing, a separation process of recovering the drained liquid and removing at least a portion of the water from the drained liquid, and a supplying process of supplying the processing liquid obtained in the separation process, which contains at least a separated liquid (organic solvent), to the surface Wf of the substrate W. However, the substrate processing method of this embodiment differs from the substrate processing method of the third embodiment in that the separation process includes a re-separation process for further separating water from the separated liquid obtained in the recovery process. This re-separation process is performed by one of the first re-separation units 310, etc. Details of the re-separation process performed by one of these units are the same as those described in the fourth embodiment. Therefore, detailed description thereof will be omitted. [Explanation of symbols]

[0162] 1: substrate processing unit, 2 to 7: recovery and recycling unit, 13: supply section, 13b: multiple valve, 20: separation section, 21: recovery pipe, 22: intermediate waste liquid storage section, 23: waste liquid discharge pipe, 24: bubble generation section, 24a: flow path narrowing section, 24b: gas supply pipe, 24c: opening and closing valve, 24d: flow path enlargement section, 24e: two-phase mixed fluid supply pipe, 25: swirl flow generation section, 25a: storage tank, 25b: exhaust pipe, 25c : Rotation drive unit, 28: Separated liquid discharge pipe, 30: Separation unit, 40: Separation unit, 100: Substrate processing device, 130: Control unit, 201: Condensation unit, 201a: Condenser, 201b: Condensed liquid discharge pipe, 201c : Separated liquid storage tank, 210: Suction part, 211: Suction pipe, 211a: Suction port, 212: Suction pump, 214: Suction liquid storage tank, 220: Swirling flow generation part, 221: Straight pipe part, 221a: Outer pipe, 22 1b: inner pipe, 300: re-separation section, 310: first re-separation section, 311: separated liquid storage section, 311b: exhaust pipe, 311a: storage tank, 312: first irradiation section, 313: circulation path, 314: separation membrane section, 320: second re-separation section, 321e: annular wall, 321d: opening, 321f: water discharge pipe, 321c: annular recovery section, 321a: storage tank, 321b: organic solvent recovery section, 321: separated liquid storage section, 3 22: heat pipe, 322a: heating section, 322b: annular cooling section, 330: third re-separation section, 331: separated liquid storage section, 332: irradiation section, 333: annular cooling section, 334: condensed liquid cooling section, 340: fourth re-separation section, 341: separated liquid storage section, 342: separated liquid cooling section, 343: removal section, 343a: circulation path, 343c: filter, 343b: pump, W: substrate, Wf: surface, α: gap section

Claims

1. A recovery and reuse unit that recovers and reuses wastewater discharged after substrate processing, a separation unit that recovers the effluent containing an organic solvent and water and separates the organic solvent from the recovered effluent, The separation unit is a bubble generating unit that mixes a gas with the waste liquid discharged after the substrate processing to generate bubbles of the gas having the organic solvent adsorbed on the surface thereof; a swirl flow generating unit that generates a swirl flow in the wastewater containing the bubbles; a recovery section that recovers a vaporized gas of the organic solvent generated from the swirling flow and / or the organic solvent concentrated in a central portion of the swirling flow; A recovery and reuse unit comprising:

2. The swirl flow generating section is a storage tank for storing the wastewater containing the bubbles; a rotation drive unit that rotates the storage tank about a central axis of the storage tank to generate a swirling flow in the wastewater containing bubbles; Equipped with The recovery unit includes: The recovery and reuse unit according to claim 1 , further comprising a condenser that liquefies the vaporized gas to produce an organic solvent.

3. The swirl flow generating section is a storage tank for storing the wastewater containing the bubbles; a rotation drive unit that rotates the storage tank about a central axis of the storage tank to generate a swirling flow in the wastewater containing bubbles; Equipped with The recovery unit includes: The recovery and reuse unit according to claim 1 , further comprising a suction section that sucks the air bubbles that gather in a central portion of the swirling flow and the organic solvent that is concentrated in the central portion.

4. The recovery unit includes: The recovery and reuse unit according to claim 3 , further comprising a condenser that liquefies the vaporized gas to produce an organic solvent.

5. a supply pipe for flowing the waste liquid containing the bubbles is connected to the bubble generating unit; the swirl flow generating unit is provided inside the supply pipe, Furthermore, a straight pipe portion of a double pipe structure having an inner pipe and an outer pipe is connected to the downstream side of the supply pipe as the recovery section, 2. The recovery and reuse unit according to claim 1, wherein the organic solvent is separated and recovered by causing the concentrated organic solvent and the air bubbles to flow in a central portion of the swirling flow through the inner pipe, and causing the water separated outside the central portion of the swirling flow to flow in a gap formed between the inner pipe and the outer pipe.

6. a substrate processing unit for processing a pattern-formed surface of a substrate; A recovery and reuse unit according to any one of claims 1 to 5; A substrate processing apparatus comprising:

7. A substrate processing method for processing a pattern-formed surface of a substrate, comprising: the method includes at least a separation step of recovering a waste liquid discharged after the substrate processing and containing an organic solvent and water, and separating the organic solvent from the recovered waste liquid; The separation step comprises: a bubble generating step of mixing a gas with the waste liquid discharged after the substrate processing to generate bubbles of the gas with the organic solvent adsorbed on the surface thereof; a swirling flow generating step of generating a swirling flow in the wastewater containing the bubbles; a recovery step of recovering a vaporized gas of the organic solvent generated from the swirling flow and / or the organic solvent concentrated in a central portion of the swirling flow; A substrate processing method comprising:

8. The swirling flow generating step includes: storing the wastewater containing the bubbles in a storage tank; a step of rotating the storage tank around a central axis of the storage tank to generate a swirling flow in the wastewater containing bubbles, The recovery step includes: The substrate processing method according to claim 7 , further comprising a condensation step of liquefying the vaporized gas to produce an organic solvent.

9. The swirling flow generating step includes: storing the wastewater containing the bubbles in a storage tank; a step of rotating the storage tank around a central axis of the storage tank to generate a swirling flow in the wastewater containing bubbles, The recovery step includes:

8. The substrate processing method according to claim 7, further comprising the step of suctioning and recovering the bubbles that gather in a central portion of the swirling flow and the organic solvent that is concentrated in the central portion.

10. The recovery step includes: The substrate processing method according to claim 9 , further comprising the step of liquefying the vaporized gas to generate and recover an organic solvent.

11. the swirling flow generating step is a step of generating the swirling flow inside a supply pipe through which the waste liquid containing the bubbles flows, a straight pipe portion of a double pipe structure having an inner pipe and an outer pipe is connected to the downstream side of the supply pipe; 8. The substrate processing method according to claim 7, wherein the recovery step separates and recovers the organic solvent by causing the organic solvent and the air bubbles concentrated in a central portion of the swirling flow to flow through the inner pipe, and causing the water separated outside the central portion of the swirling flow to flow through a gap formed between the inner pipe and the outer pipe.

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