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 or water from the recovered waste liquid, and the separation section 20 comprises a waste liquid storage section 24 that stores the waste liquid discharged after the substrate processing, a gas-liquid separation section for vaporizing either the water or the organic solvents contained in the waste liquid stored in the waste liquid storage section 24 to separate them from each other, and / or a solid-liquid separation section for solidifying the water contained in the waste liquid stored in the waste liquid storage section 24 and separating it from the organic solvents.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 effluent discharged after substrate processing, and includes at least a separation section that recovers the effluent containing an organic solvent and water and separates the organic solvent or the water from the recovered effluent, wherein the separation section includes: an effluent storage section that stores the effluent discharged after the substrate processing; a gas-liquid separation section that vaporizes either the organic solvent or the water in the effluent stored in the effluent storage section to separate them from each other; and / or a solid-liquid separation section that solidifies the water in the effluent stored in the effluent storage section to separate it from the organic solvent.

[0008] In the above configuration, the gas-liquid separation unit may include a first irradiation unit that irradiates the waste liquid stored in the waste liquid storage unit with first light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water, thereby vaporizing the water contained in the waste liquid.

[0009] In the above configuration, the gas-liquid separation unit may include a heating unit that heats the effluent stored in the effluent storage unit to a temperature that is equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water, thereby vaporizing the organic solvent, and a first cooling unit that cools the vaporized organic solvent to produce the organic solvent in a liquid state, and the boiling point of the organic solvent may be lower than the boiling point of water.

[0010] In the above configuration, the solid-liquid separation unit may include a second cooling unit that cools the effluent stored in the effluent storage unit to a temperature higher than the freezing point of the organic solvent and equal to or lower than the freezing point of water to precipitate ice, and the gas-liquid separation unit may include a second irradiation unit that irradiates the effluent containing ice precipitated by cooling by the second cooling unit with second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent to vaporize the organic solvent contained in the effluent, and a first cooling unit that cools the vaporized organic solvent to produce the organic solvent in liquid form, and the freezing point of the organic solvent may be lower than the freezing point of water.

[0011] In the above configuration, the solid-liquid separation unit may include a second cooling unit that cools the effluent stored in the effluent storage unit to a temperature that is higher than the freezing point of the organic solvent and equal to or lower than the freezing point of water to precipitate ice, and a removal unit that removes the ice in the effluent, and the freezing point of the organic solvent may be lower than the freezing point of water.

[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 or the water from the recovered waste liquid, wherein the separation step includes a storage step of storing the waste liquid discharged after the substrate processing, a gas-liquid separation step of vaporizing either the organic solvent or the water in the stored waste liquid to separate them from each other, and / or a solid-liquid separation step of solidifying the water in the stored waste liquid to separate it from the organic solvent.

[0014] In the above configuration, the gas-liquid separation step may include a first irradiation step of irradiating the stored waste liquid with first light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water, thereby vaporizing the water contained in the waste liquid.

[0015] In the above-described configuration, the gas-liquid separation step may include a heating step of heating the stored waste liquid to a temperature that is equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water to vaporize the organic solvent, and a first cooling step of cooling the vaporized organic solvent to produce the organic solvent in a liquid state, and the boiling point of the organic solvent may be lower than the boiling point of water.

[0016] In the above-described configuration, the solid-liquid separation step may include a second cooling step of cooling the stored effluent to a temperature higher than the freezing point of the organic solvent and equal to or lower than the freezing point of water to precipitate ice, and the gas-liquid separation step may include a second irradiation step of irradiating the effluent containing the ice precipitated in the second cooling step with second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent to vaporize the organic solvent contained in the effluent, and a first cooling step of cooling the vaporized organic solvent to produce the organic solvent in liquid form, wherein the freezing point of the organic solvent is lower than the freezing point of water.

[0017] In the above-described configuration, the solid-liquid separation step may include a second cooling step of cooling the stored effluent to a temperature higher than the freezing point of the organic solvent and equal to or lower than the freezing point of water to precipitate ice, and a removal step of removing the ice in the effluent, wherein the freezing point of the organic solvent is lower than the freezing point of water. [Effects of the Invention]

[0018] According to the present invention, after a substrate processing process is completed, a wastewater containing water and an organic solvent is recovered, and then either the water or the organic solvent contained in the wastewater is vaporized and separated. Alternatively, the water contained in the wastewater is solidified to form ice, which is then separated from the organic solvent. This allows the organic solvent to be recovered and the amount of waste organic solvent to be reduced 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 during 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] 10 is an explanatory diagram schematically illustrating another waste liquid storage section and a first irradiation section in the recovery and reuse unit according to the first embodiment of the present invention. FIG. [Figure 4] 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 5] FIG. 10 is an explanatory diagram schematically illustrating a waste liquid storage section and a heat pipe in a recovery and reuse unit according to a second embodiment of the present invention. [Figure 6]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 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 fourth embodiment of the present invention. [Figure 8] FIG. 10 is an explanatory diagram schematically showing a waste liquid storage section, a second irradiation section, a first cooling section, and a second cooling section in a recovery and reuse unit according to a fourth embodiment. [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 fifth embodiment of the present invention. [Figure 10] 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. [Figure 11] FIG. 13 is an explanatory diagram schematically illustrating a waste liquid storage section, a first irradiation section, and a heat pipe in a recovery and reuse unit according to a sixth embodiment. 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 100 of this embodiment. In FIG. 2, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationships of the objects shown. 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 FIG.

[0043] The recovery / reuse unit 2 recovers the processing liquid used for substrate processing in the substrate processing unit 1, and separates and removes water from the recovered processing liquid to make it reusable. The recovery / 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 / reuse unit 2 includes at least a separation section 20 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 waste liquid storage unit 24, a first irradiation unit 25, a circulation path 26, a separation membrane unit 27, and a separation liquid discharge pipe 28.

[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 effluent storage 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 the upstream side to the downstream side.

[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 effluent storage 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 effluent storage unit 24 includes a storage tank 24a and an exhaust pipe 24b provided on the upper part of the storage tank 24a. The storage tank 24a can store the effluent supplied from the intermediate effluent storage unit 22 via the effluent discharge pipe 23. The exhaust pipe 24b can also discharge water vapor generated by evaporation of water contained in the stored effluent to the outside of the effluent storage unit 24.

[0049] The first irradiating unit 25 irradiates the effluent stored in the effluent storage unit 24 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 25 functions as a gas-liquid separating unit that vaporizes the water contained in the effluent and separates it from the organic solvent. The first irradiating unit 25 is disposed, for example, above the effluent storage unit 24, and can irradiate the effluent stored in the effluent storage unit 24 with the first light from above.

[0050] Specifically, the first irradiation unit 25 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 wastewater storage unit 24. As a result, the water in the wastewater 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 wastewater. 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:

[0051] The circulation path 26 is sequentially provided, from upstream to downstream, with a pump 26a, a filter 26b, and a separation membrane unit 27. The pump 26a is controlled by operational commands from the control unit 130, and can send the organic solvent separated from the wastewater in the wastewater storage unit 24 to the circulation path 26. The filter 26b 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 26b. A three-way valve 26c is provided at the branch point where the separated liquid discharge pipe 28 branches off from the circulation path 26. By providing the three-way valve 26c at the branch point, the flow path of the separated liquid flowing through the circulation path 26 can be changed to the separated liquid discharge pipe 28. The three-way valve 26c is electrically connected to the control unit 130, and the change in flow path by the three-way valve 26c is controlled by operational commands from the control unit 130.

[0052] The separation membrane section 27 can further separate water from the separated liquid (organic solvent) discharged from the waste liquid storage section 24. By providing the separation membrane section 27, the water removal rate can be further improved. An example of a separation membrane used in the separation membrane section 27 is a dehydration membrane that allows water to pass through but does not allow organic solvents such as IPA to pass through. 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 27a that discharges water separated from the waste liquid is connected to the separation membrane section 27.

[0053] One end of the separated liquid discharge pipe 28 is connected to the circulation path 26, and the other end is connected to the multiple valve 13b. This allows the separated liquid (organic solvent) from which water has been removed from the waste liquid to be supplied from the waste liquid storage section 24 to the multiple valve 13b. In addition, a pump 28a and a flow rate adjustment 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 section 130, and can supply the separated liquid to the connection section 131 of the multiple valve 13b. In addition, the flow rate adjustment valve 28b can adjust the flow rate of the separated liquid.

[0054] In the recovery and reuse unit 2 of this embodiment, an effluent reservoir 24' equipped with a centrifugal separation function as shown in FIG. 3 may be used instead of the effluent reservoir 24 shown in FIG. 3. FIG. 3 is a schematic diagram illustrating the overall configuration of the effluent reservoir 24' equipped with a centrifugal separation function. The effluent reservoir 24' shown in FIG. 3 includes a reservoir 24a, an exhaust pipe 24b, a rotational drive unit 24c, and a chamber 24d. The rotational drive unit 24c rotates around an axis B along the Z direction in response to an operation command from the control unit 130. The rotational drive unit 24c is mounted while holding the reservoir 24a and is configured with a known belt, motor, and rotating shaft. As the rotational drive unit 24c rotates around the axis B, the reservoir 24a held by the rotational drive unit 24c can also rotate around the axis B. The chamber 24d can accommodate the reservoir 24a and the rotational drive unit 24c. In addition, an exhaust pipe 24b is provided at the top of the chamber 24d, and can exhaust water vapor generated from the waste liquid.

[0055] In the waste liquid storage unit 24' shown in FIG. 3, by rotating the storage tank 24a, a swirling flow centered on axis B can be generated in the waste liquid stored in the storage tank 24a. In the swirling flow, water vapor generated by the irradiation of the first light by the first irradiation unit 25 has a low specific gravity and therefore gathers near the center of the storage tank 24a (axis B and its vicinity). As a result, larger bubbles made of water vapor are generated near the center of the storage tank 24a, and can be efficiently separated from the waste liquid. The rotation speed of the storage tank 24a can be set appropriately as needed.

[0056] Furthermore, in the recovery and reuse unit 2 of this embodiment, a separation membrane section 27 may be provided midway along the path of the waste liquid discharge pipe 23. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating water from the waste liquid.

[0057] [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 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 step of draining the processing liquid after substrate processing, a separating 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 separating step onto the surface Wf of the substrate W.

[0058] 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. 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. The waste liquid discharged through the recovery pipe 21 is stored in the intermediate waste liquid storage unit 22.

[0059] The separation process is a process of separating and removing water from the effluent collected and stored in the intermediate effluent storage unit 22 to obtain a separated liquid (organic solvent). When the valve 23c is opened in response to an operational command from the control unit 130, the pump 23b operates to send the effluent stored in the intermediate effluent storage unit 22 through the effluent discharge pipe 23 and to the storage tank 24a of the effluent storage unit 24, where it is stored (storage process). When a predetermined amount of effluent is stored in the storage tank 24a, the control unit 130 issues an operational command to the valve 23c to close the valve. Furthermore, in response to an operational command from the control unit 130, the first irradiation unit 25 irradiates the effluent stored in the storage tank 24a with 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 the organic solvent, but includes the absorption wavelength band of water. Therefore, only the water contained in the effluent evaporates as water vapor. Only the separated liquid (organic solvent) is stored in the storage tank 24a. The irradiation amount of the first light can be set appropriately as needed. The water vapor is exhausted from the exhaust pipe 24b. Furthermore, the degree of water vaporization can be controlled by adjusting the irradiation amount of the first light. For example, increasing the irradiation amount of the first light can promote the evaporation of water contained in the effluent, thereby increasing the amount of water vapor.

[0060] Furthermore, when an effluent storage unit 24' with a centrifugal separation function is used instead of the effluent storage unit 24 (see FIG. 3), the first light is irradiated by the first irradiator 25 while the storage tank 24a is rotated around the axis B. The rotation of the storage tank 24a is performed by the rotation drive unit 24c rotating in response to an operation command from the control unit 130. In this way, by swirling the effluent stored in the storage tank 24a by a swirling flow, even if water vapor is generated as tiny bubbles, the water vapor can be collected near the center of the storage tank 24a and turned into larger bubbles. As a result, the water vapor can be easily separated from the effluent. The rotation speed of the storage tank 24a is not particularly limited as long as it does not cause the stored effluent to overflow, and can be set appropriately.

[0061] When the water in the effluent is separated as water vapor and removed, the first irradiator 25 stops irradiating the first light in response to an operation command from the controller 130. Furthermore, when the effluent reservoir 24' is used, the controller 130 also stops the rotation of the rotation driver 24c in response to an operation command from the controller 130.

[0062] Furthermore, in the separation process, water is removed from the separated liquid (organic solvent) separated from the waste liquid using a separation membrane unit 27. Specifically, the organic solvent irradiated by the first irradiation unit 25 is circulated through a circulation path 26 by operation of a pump 26a. Impurities such as metal ions are removed from the organic solvent flowing through the circulation path 26 by a filter 26b installed midway through the circulation path 26, and then the water contained in the organic solvent is further separated and removed by the separation membrane unit 27. The separated water is discharged through a water discharge pipe 27a. 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 26c 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 26c, and the organic solvent is returned to the reservoir 24a via the circulation path 26. The circulation of the organic solvent in the circulation path 26 continues until the measured value of the concentration of the organic solvent by the concentration meter reaches the predetermined value.

[0063] The supplying step is a step of generating a processing liquid containing at least the separation liquid (organic solvent) obtained in the separating step and supplying the processing liquid to the surface Wf of the substrate W. In this step, the 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 separation liquid stored in the storage tank 24a is supplied to the multiple valve 13b via the separation liquid discharge pipe 28.

[0064] The concentration of the organic solvent contained in the processing liquid supplied to the substrate W may be adjusted by appropriately mixing the separation liquid supplied from the waste liquid reservoir 24, 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 adjustment 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 adjustment valve 145.

[0065] As described above, in this embodiment, the wastewater is 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 wastewater. 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 zeolite membranes, etc.

[0066] (Second embodiment) A second embodiment of the present invention will now be described.

[0067] [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.

[0068] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing unit 110 will be described below with reference to FIG. 4. FIG. 4 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 3 in the substrate processing apparatus of this embodiment. In FIG. 4, 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.

[0069] 4, the recovery / reuse unit 3 of this embodiment, like the recovery / reuse unit 2 of the first embodiment, recovers the processing liquid used to remove water remaining on the front surface Wf of the substrate W, and separates and removes the water from the recovered processing liquid to make it reusable. Specifically, the recovery / reuse unit 3 includes at least a separation section 30, as shown in FIG.

[0070] The separation section 30 includes at least a recovery pipe 21, a waste liquid storage section 31, a heat pipe as a gas-liquid separation section, a circulation path 26, a separation membrane section 27, and a separated liquid discharge pipe .

[0071] The recovery pipe 21 directly supplies the waste liquid discharged from the splash prevention cup 14 to the waste liquid storage section 31. One end of the recovery pipe 21 is connected to the splash prevention cup 14, and the other end is connected to the waste liquid storage section 31. Along the path of the recovery pipe 21, a filter 23a, a pump 23b, and a valve 23c are provided in this order from the upstream side to the downstream side.

[0072] As shown in FIG. 5, the waste liquid storage unit 31 includes a storage tank 31a, an organic solvent recovery unit 31b for recovering the organic solvent, and a water discharge pipe 31f for discharging water separated from the waste liquid. FIG. 5 is a schematic explanatory diagram of the waste liquid storage unit 31 and the heat pipe 32. The storage tank 31a can store the waste liquid supplied from the splash prevention cup 14 via the recovery pipe 21. The organic solvent recovery unit 31b is provided above the liquid level of the waste liquid stored in the storage tank 31a and has an annular recovery unit 31c and an opening 31d. The annular recovery unit 31c is provided so as to extend in an annular shape from the inner wall of the storage tank 31a toward the center. The opening 31d is provided in the center of the annular recovery unit 31c and is formed by an annular wall 31e standing in a direction approximately perpendicular to the annular recovery unit 31c. The provision of annular wall 31e prevents the liquid organic solvent from flowing down into the waste liquid stored in storage tank 31a. Furthermore, the provision of opening 31d in the center of annular recovery unit 31c allows the vaporized organic solvent to rise to annular cooling unit 32b (details will be described later). Water discharge pipe 31f allows water separated from the waste liquid by vaporizing the organic solvent to be discharged from storage tank 31a to the outside.

[0073] The connection position of the recovery pipe 21 in the storage tank 31a is located below the position where the organic solvent recovery unit 31b is provided. In addition, the storage tank 31a is connected to the circulation path 26 so that the organic solvent recovered from the wastewater and stored in the organic solvent recovery unit 31b is discharged to the circulation path 26 and the organic solvent circulated through the circulation path 26 returns to the organic solvent recovery unit 31b.

[0074] As shown in FIG. 5, the heat pipe 32 includes a heating unit 32a and an annular cooling unit (first cooling unit) 32b. The heating unit 32a is thermally connected to the storage tank 31a and heats the wastewater stored in the storage tank 31a by radiating heat. The heating unit 32a heats the wastewater 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 wastewater. The annular cooling unit 32b absorbs heat (receives heat) from the organic solvent vaporized by the heating unit 32a and rising through the opening 31d, thereby cooling it. The annular cooling unit 32b can convert the organic solvent vapor to a liquid state by cooling it to a temperature lower than the liquefaction temperature of the organic solvent. The annular cooling unit 32b is annularly disposed around the central axis of the storage tank 31a. The annular cooling unit 32b has an inner diameter larger than the opening diameter of the opening 31d of the organic solvent recovery unit 31b. This allows the organic solvent in a liquid state to be reliably collected in the annular recovery portion 31c, and prevents it from dropping into the drainage through the opening 31d.

[0075] The circulation path 26 is sequentially provided, from upstream to downstream, with a pump 26a, a filter 26b, and a separation membrane unit 27. The pump 26a is controlled by operational commands from the control unit 130, and can send the organic solvent separated from the wastewater in the wastewater storage unit 31 to the circulation path 26. The filter 26b 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 26b. A three-way valve 26c is provided at the branch point where the separated liquid discharge pipe 28 branches off from the circulation path 26. By providing the three-way valve 26c at the branch point, the flow path of the separated liquid flowing through the circulation path 26 can be changed to the separated liquid discharge pipe 28. The three-way valve 26c is electrically connected to the control unit 130, and the change in flow path by the three-way valve 26c is controlled by operational commands from the control unit 130.

[0076] In the recovery / reuse unit 3 of this embodiment, a separation membrane section 27 may be further provided midway along the recovery pipe 21. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating the organic solvent from the wastewater.

[0077] Furthermore, in the recovery / reuse unit 3 of this embodiment, as in the recovery / reuse unit 2 of the first embodiment, a valve 21a and an intermediate effluent storage section 22 may be provided midway along the recovery pipe 21. More specifically, the valve 21a and the intermediate effluent storage section 22 may be provided sequentially between the splash prevention cup 14 and the filter 23a. This allows the separation process to proceed stably even when the discharge of effluent from the splash prevention cup 14 is delayed. Furthermore, even when heating the effluent using the heat pipe 32 requires time to separate the organic solvent, it is possible to prevent an excessive supply of effluent to the effluent storage section 31.

[0078] Furthermore, in the recovery and reuse unit 3 of this embodiment, a storage tank (not shown) for storing the separated liquid (organic solvent) may be provided midway along the circulation path 26. In this case, the storage tank is provided between the waste liquid storage section 31 and the pump 26a. By providing the storage tank, even when it takes time to separate a certain amount of organic solvent from the waste liquid into gas and liquid, the organic solvent can be stably circulated through the circulation path 26 or supplied to the multiple valve 13b.

[0079] [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 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 separating step onto the surface Wf of the substrate W. In this embodiment, the supplying step is the same as in the first embodiment, and therefore will not be described below.

[0080] First, in the draining step, when valve 23c is opened by an operation command from control unit 130, pump 23b is operated and the processing liquid collected in splash prevention cup 14 is discharged as drainage through recovery pipe 21 connected to splash prevention cup 14. Filter 23a is provided midway along recovery pipe 21, and filter 23a removes impurities from the drainage.

[0081] Next, in the separation step, the effluent from which impurities have been removed by the filter 23a is supplied to the storage tank 31a of the effluent storage unit 31 and stored therein (storage step). When a predetermined amount of effluent has been stored in the storage tank 31a, the control unit 130 issues an operation command to the valve 23c to close it. Furthermore, in response to an operation command from the control unit 130, the heating unit 32a of the heat pipe 32 heats the effluent stored in the storage tank 31a (gas-liquid separation step, heating step). As described above, the heating temperature of the heating unit 32a is in the range of the boiling point of the organic solvent or higher and lower than the boiling point of water. Therefore, only the organic solvent contained in the effluent vaporizes. The vaporized organic solvent rises through the opening 31d of the organic solvent recovery unit 31b and comes into contact with the annular cooling unit 32b, 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 drainage liquid but is collected in the annular recovery section 31c.

[0082] Furthermore, in the separation process, water is removed from the organic solvent separated from the wastewater using a separation membrane unit 27. Specifically, the organic solvent collected in the annular recovery unit 31c is circulated through the circulation path 26 by operating the pump 26a. After impurities such as metal ions are removed from the organic solvent flowing through the circulation path 26 by a filter 26b installed midway through the circulation path 26, the separation membrane unit 27 separates and removes the water contained in the organic solvent. The separated water is discharged through a water discharge pipe 27a. 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 26c 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 26c to change the flow path, and the organic solvent is returned to the annular recovery unit 31c of the organic solvent recovery unit 31b via the circulation path 26. The circulation of the organic solvent through the circulation path 26 continues until the measured value of the organic solvent concentration by the concentration meter reaches a predetermined value. The organic solvent separated from the wastewater in the separation step can be reused as a treatment liquid in the supply step, as in the first embodiment.

[0083] As described above, in this embodiment, only the organic solvent contained in the wastewater is vaporized and separated by heating within a temperature range equal to or higher than the boiling point of the organic solvent and lower than the boiling point of 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 zeolite membranes or the like.

[0084] (Third embodiment) A third embodiment of the present invention will now be described.

[0085] [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 and second embodiments, except for the substrate processing units and the recovery / recycling unit of the substrate processing section 110 (see FIG. 1). Therefore, detailed description of the indexer section 120 and the control section 130 will be omitted, with the same reference numerals assigned to them.

[0086] <Substrate processing unit> The configuration of the substrate processing unit 1' in the substrate processing section 110 will be described below with reference to FIG. 6. FIG. 6 is an explanatory diagram schematically showing the substrate processing unit 1' and the recovery / recycling unit 4 in the substrate processing apparatus 100 of this embodiment. In FIG. 6, XYZ orthogonal coordinate axes are appropriately displayed to clarify the directional relationships of the objects shown. In the figure, the XY plane represents the horizontal plane, and the +Z direction represents the vertical upward direction.

[0087] The substrate processing unit 1' of this embodiment differs from the substrate processing unit 1 of the first embodiment in that it includes an SPM scattering prevention cup 15 for preventing scattering of SPM, which is a mixture of sulfuric acid and hydrogen peroxide solution. The SPM scattering prevention cup 15 is provided to surround the SPM scattering prevention cup 14. The SPM scattering prevention cup 15 is connected to a lifting drive mechanism (not shown) and is movable up and down in the Z direction shown in FIG. 6. When SPM is supplied to the surface Wf of the substrate W, the lifting drive mechanism lowers the SPM scattering prevention cup 14, and the SPM scattering prevention cup is positioned at a predetermined position as shown in FIG. 6, surrounding the substrate W held by the chuck pins 12c from a lateral position. This makes it possible to collect SPM scattered from the substrate W and the spin base 12b.

[0088] <Recycling unit> Next, the configuration of the recovery / recycling unit 4 in the substrate processing section 110 will be described below with reference to FIG.

[0089] 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, the recovery / reuse unit 4 includes at least a separation section 40, as shown in FIG.

[0090] The separation unit 40 includes at least a recovery pipe 21, an intermediate effluent storage unit 22, an effluent discharge pipe 23, an effluent storage unit 31, a heat pipe 32, a circulation path 26, a separation membrane unit 27, a separated liquid discharge pipe 28, and an SPM discharge unit 41.

[0091] The intermediate effluent reservoir 22 is connected to the effluent reservoir 31 via the effluent discharge pipe 23. The intermediate effluent reservoir 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.

[0092] The SPM discharge unit 41 includes an SPM recovery pipe 41a, a heat exchanger 41b, an SPM discharge pipe 41c, and a valve 41d. The SPM recovery pipe 41a recovers the SPM effluent discharged from the SPM scattering prevention cup 15. The heat exchanger 41b is connected to the SPM recovery pipe 41a and is provided inside the intermediate effluent storage unit 22. SPM is typically used for substrate processing at high temperatures, for example, 100°C or higher. Therefore, by flowing the SPM effluent through the heat exchanger 41b, the effluent stored in the intermediate effluent storage unit 22 can be heated by the heat of the effluent. The heat exchanger 41b is not particularly limited, and examples thereof include a throw-in type heat exchanger. The SPM discharge pipe 41c is connected to the heat exchanger 41b and discharges the SPM effluent used to heat the effluent stored in the intermediate effluent storage unit 22. Valve 41d is provided midway along the SPM recovery pipe 41a. Valve 41d is electrically connected to the control unit 130 and is normally closed. The opening and closing of valve 41d is controlled by an operation command from the control unit 130. When valve 41d is opened by an operation command from the control unit 130, the SPM wastewater collected by SPM scattering prevention cup 15 passes through SPM recovery pipe 41a and is supplied to heat exchanger 41b.

[0093] In the recovery / reuse unit 4 of this embodiment, a separation membrane section 27 may be further provided in the path of the waste liquid discharge pipe 23. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating the organic solvent from the waste liquid.

[0094] Furthermore, in the recovery and reuse unit 4 of this embodiment, a storage tank (not shown) for storing the separated liquid (organic solvent) may be provided midway along the circulation path 26. In this case, the storage tank is provided between the waste liquid storage section 31 and the pump 26a. By providing the storage tank, even when it takes time to separate a certain amount of organic solvent from the waste liquid into gas and liquid, the organic solvent can be stably circulated through the circulation path 26 or supplied to the multiple valve 13b.

[0095] [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, an SPM draining process of draining the SPM 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 containing at least the separated liquid (organic solvent) obtained in the separation process onto the surface Wf of the substrate W. Note that in this embodiment, the supplying process is the same as in the first embodiment, and therefore its description will be omitted below.

[0096] The liquid draining step is a step of draining, from the substrate processing unit 1′, the processing liquid used in substrate processing on the front surface Wf of the substrate W. When the valve 21a is opened in response to an operation command from the control unit 130, the processing liquid collected in the splash prevention cup 14 is discharged as waste liquid through the recovery pipe 21 connected to the splash prevention cup 14. The waste liquid discharged through the recovery pipe 21 is stored in the intermediate waste liquid storage unit 22.

[0097] The SPM discharge step is a step of discharging SPM used in substrate processing on the surface Wf of the substrate W from the substrate processing unit 1′. When the valve 41d is opened in response to an operation command from the control unit 130, the SPM collected in the SPM scattering prevention cup 15 is discharged as wastewater through the SPM recovery pipe 41a connected to the SPM scattering prevention cup 15 and supplied to the heat exchanger 41b. Because the SPM as wastewater is high in temperature, it heats the wastewater stored in the intermediate wastewater storage unit 22 as it flows through the heat exchanger 41b. By heating the wastewater in advance, it is possible to improve energy efficiency when the wastewater is heated by the heating unit 32a of the heat pipe 32 in the storage tank 31a of the wastewater storage unit 31 in the separation step described below, thereby achieving power saving.

[0098] The separation step is a step of producing a separated liquid (organic solvent) by separating and removing water from the effluent stored in the intermediate effluent storage section 22 and heated by the exhaust heat of the SPM. When the valve 23c is opened in response to an operation command from the control section 130, the pump 23b is operated to cause the effluent stored in the intermediate effluent storage section 22 to flow through the effluent discharge pipe 23, and impurities are removed by the filter 23a provided midway along the effluent discharge pipe 23.

[0099] Furthermore, the effluent from which impurities have been removed by the filter 23a is supplied to the storage tank 31a of the effluent storage unit 31 and stored there (storage step). When a predetermined amount of effluent has been stored in the storage tank 31a, the control unit 130 issues an operation command to the valve 23c to close the valve. Furthermore, in response to an operation command from the control unit 130, the heating unit 32a of the heat pipe 32 heats the effluent stored in the storage tank 31a (gas-liquid separation step, heating step). The heating temperature of the heating unit 32a is in the range of the boiling point of the organic solvent or higher and lower than the boiling point of water. Therefore, only the organic solvent contained in the effluent is vaporized. The vaporized organic solvent rises through the opening 31d of the organic solvent recovery unit 31b and comes into contact with the annular cooling unit 32b, where it is cooled and becomes a liquid (gas-liquid separation step, first cooling step). The liquid organic solvent (separated liquid) does not fall into the effluent but is collected by the annular recovery unit 31c.

[0100] Furthermore, in the separation process, water is removed from the organic solvent separated from the wastewater using a separation membrane unit 27. Specifically, the organic solvent collected in the annular recovery unit 31c is circulated through the circulation path 26 by operating the pump 26a. After impurities such as metal ions are removed from the organic solvent flowing through the circulation path 26 by a filter 26b installed midway through the circulation path 26, the separation membrane unit 27 separates and removes the water contained in the organic solvent. The separated water is discharged through a water discharge pipe 27a. 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 26c 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 26c to change the flow path, and the organic solvent is returned to the annular recovery unit 31c of the organic solvent recovery unit 31b via the circulation path 26. The circulation of the organic solvent through the circulation path 26 continues until the measured value of the organic solvent concentration by the concentration meter reaches a predetermined value. The organic solvent separated from the wastewater in the separation step can be reused as a treatment liquid in the supply step, as in the first and second embodiments.

[0101] As described above, in this embodiment, the waste heat of used SPM is utilized to heat the wastewater within a temperature range equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water, thereby vaporizing and separating only the organic solvent contained in the wastewater. This separation method can further 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.

[0102] (Fourth embodiment) A fourth embodiment of the present invention will now be described.

[0103] [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.

[0104] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing apparatus 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 5 in the substrate processing apparatus 100 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.

[0105] 7, the recovery / reuse unit 5 of the present embodiment, like the recovery / reuse unit 2 of the first embodiment, recovers the processing liquid used to remove water remaining on the front surface Wf of the substrate W, and separates and removes the water from the recovered processing liquid to make it reusable. Specifically, the recovery / reuse unit 5 includes at least a separation section 50, as shown in FIG.

[0106] The separation section 50 includes at least a recovery pipe 21, an intermediate effluent storage section 22, an effluent discharge pipe 23, an effluent storage section 51, a second irradiation section (gas-liquid separation section), a circular cooling section (first cooling section), an effluent cooling section (second cooling section), a circulation path 26, a separation membrane section 27, and a separated liquid discharge pipe 28.

[0107] As shown in FIG. 8, the effluent storage unit 51 includes a storage tank 31a, an organic solvent recovery unit 31b for recovering the organic solvent, and a water discharge pipe 31f for discharging water separated from the effluent. FIG. 8 is an explanatory diagram schematically illustrating the effluent storage unit 51, the second irradiation unit 52, the annular cooling unit 53, and the effluent cooling unit 54. The storage tank 31a can store the effluent supplied from the intermediate effluent storage unit 22 via the effluent discharge pipe 23. The organic solvent recovery unit 31b is provided above the liquid level of the effluent stored in the storage tank 31a and has an annular recovery unit 31c and an opening 31d. The annular recovery unit 31c is provided so as to extend in an annular shape from the inner wall of the storage tank 31a toward the center. The opening 31d is provided in the center of the annular recovery unit 31c and is formed by an annular wall 31e standing in a direction approximately perpendicular to the annular recovery unit 31c. The provision of annular wall 31e prevents the liquid organic solvent from flowing down into the waste liquid stored in storage tank 31a. Furthermore, the provision of opening 31d in the center of annular recovery section 31c allows the vaporized organic solvent to rise to annular cooling section 53 (details of which will be described later). Water discharge pipe 31f allows water separated from the waste liquid by vaporizing the organic solvent to be discharged from storage tank 31a to the outside.

[0108] The second irradiator 52 irradiates the effluent stored in the storage tank 31a 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 52 functions as a gas-liquid separator that vaporizes the organic solvent contained in the effluent and separates it from the effluent. For example, if the storage tank 31a is transparent to the second light, the second irradiator 52 can be disposed on the side of the storage tank 31a to irradiate the effluent stored in the storage tank 31a with the second light.

[0109] The position where the second irradiating unit 52 is disposed is not particularly limited as long as the second light can be irradiated onto the effluent stored in the storage tank 31a. For example, the second irradiating unit 52 may be disposed inside the storage tank 31a. In this way, even if the storage tank 31a is not transparent to the second light, the second light can be irradiated onto the effluent stored in the storage tank 31a.

[0110] Specifically, the second irradiation unit 52 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 31a. As a result, the organic solvent in the effluent can be efficiently heated and vaporized. The organic solvent is separated from water in the effluent 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.

[0111] The annular cooling unit 53 cools the organic solvent that has evaporated from the effluent and rises through the opening 31d. The annular cooling unit 53 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 53 is annularly disposed about the central axis of the storage tank 31a. The annular cooling unit 53 is also formed so that its inner diameter is larger than the opening diameter of the opening 31d of the organic solvent recovery unit 31b. This ensures that the liquid organic solvent is reliably collected by the annular recovery unit 31c and prevents it from falling into the effluent through the opening 31d.

[0112] The effluent cooling unit 54 functions as a solid-liquid separation unit by cooling the effluent stored in the storage tank 31a to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice 55. A known device can be used as the effluent cooling unit 54, and specific examples include a Peltier element.

[0113] In the recovery / reuse unit 5 of this embodiment, a separation membrane section 27 may be further provided in the path of the waste liquid discharge pipe 23. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating the organic solvent from the waste liquid.

[0114] Furthermore, in the recovery and reuse unit 5 of this embodiment, a storage tank (not shown) for storing the separated liquid (organic solvent) may be provided midway along the circulation path 26. In this case, the storage tank is provided between the waste liquid storage section 51 and the pump 26a. By providing the storage tank, even when it takes time to separate a certain amount of organic solvent from the waste liquid into gas and liquid, the organic solvent can be stably circulated through the circulation path 26 or supplied to the multiple valve 13b.

[0115] [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 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 separating step onto the surface Wf of the substrate W. Note that 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.

[0116] The separation step is a step of separating and removing water from the effluent collected and stored in the effluent storage unit 51 to obtain a separated liquid (organic solvent). When the valve 23c is opened in response to an operational command from the control unit 130, the pump 23b operates to cause the effluent stored in the intermediate effluent storage unit 22 to flow through the effluent discharge pipe 23 and be sent to the storage tank 31a of the effluent storage unit 51, where it is stored (storage step). When a predetermined amount of effluent is stored in the storage tank 31a, the control unit 130 issues an operational command to close the valve 23c. Furthermore, in response to an operational command from the control unit 130, the effluent cooling unit 54 cools the effluent stored in the storage tank 31a (solid-liquid separation step, second cooling step). As described above, the cooling temperature of the effluent cooling unit 54 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 effluent solidifies, forming ice 55. This allows solid-liquid separation of the organic solvent and water to proceed in the wastewater.

[0117] In this embodiment, the effluent collected in the splash prevention cup 14 is not directly supplied to the effluent storage section 51, but is temporarily stored in the intermediate effluent storage section 22, so that the separation process can proceed stably even when the discharge of the effluent from the splash prevention cup 14 is delayed. Also, even when it takes time to generate ice 55 by cooling the effluent using the effluent cooling section 54 (i.e., solid-liquid separation), it is possible to prevent the effluent from being excessively supplied to the effluent storage section 51.

[0118] In the separation step, the control unit 130 issues an operational command to the second irradiation unit 52, which irradiates the wastewater stored in the storage tank 31a 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 range of water but includes the absorption wavelength range of the organic solvent. Therefore, only the organic solvent contained in the wastewater is vaporized and evaporated. The vaporized organic solvent rises through the opening 31d of the organic solvent recovery unit 31b and is cooled by contacting the annular cooling unit 53 (gas-liquid separation step, first cooling step). The cooling temperature of the annular cooling unit 53 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 31c without falling into the wastewater. Only water, or water and ice 55, is stored in the storage tank 31a. Furthermore, the water remaining in the storage tank 31a is discharged through the water discharge pipe 31f. Furthermore, the ice 55 remaining in the storage tank 31a is thawed naturally or heated to turn into water, and then discharged through the water discharge pipe 31f. The irradiation amount of the second light can be set appropriately as needed. The water is discharged through the water discharge pipe 31f. 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 effluent, thereby increasing the amount of vapor of the organic solvent.

[0119] As described above, in this embodiment, the waste liquid is cooled to solidify the water, thereby performing solid-liquid separation, and the organic solvent in the waste liquid is vaporized to perform gas-liquid separation. This separation method can more efficiently separate and recover the organic solvent while suppressing an increase in running costs, compared to conventional membrane separation methods using a zeolite membrane or the like, and can reduce the amount of organic solvent discarded.

[0120] (Fifth embodiment) A fifth embodiment of the present invention will now be described.

[0121] [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.

[0122] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing apparatus 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 6 in the substrate processing apparatus 100 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.

[0123] 9, the recovery / reuse unit 6 of the present embodiment recovers the processing liquid used to remove water remaining on the front surface Wf of the substrate W, and separates and removes the water from the recovered processing liquid to make it reusable, similar to the recovery / reuse unit 2 of the first embodiment. Specifically, the recovery / reuse unit 6 includes at least a separation section 60, as shown in FIG.

[0124] The separation section 60 includes at least a recovery pipe 21, an intermediate effluent storage section 22, an effluent discharge pipe 23, an effluent storage section 61, an effluent cooling section (second cooling section) 62, a removal section 63, and a separated liquid discharge pipe 28.

[0125] The waste liquid storage section 61 can store the waste liquid supplied from the intermediate waste liquid storage section 22 via the waste liquid discharge pipe 23.

[0126] The effluent cooling unit 62 functions as a solid-liquid separation unit by cooling the effluent stored in the effluent storage unit 61 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 effluent cooling unit 62, a known cooling unit can be used, and specific examples include a Peltier element.

[0127] The removal unit 63 includes at least a circulation path 63a, a pump 63b, a filter 63c, and a valve 63d. The pump 63b, the filter 63c, and the valve 63d are sequentially arranged along the circulation path 63a from upstream to downstream. The pump 63b is controlled by operational commands from the control unit 130, and can solidify water in the wastewater storage unit 61 to separate the organic solvent into solid and liquid, and then send the organic solvent to the circulation path 63a. The filter 63c can separate and remove ice contained in the organic solvent. The valve 63d is electrically connected to the control unit 130 and is normally closed. The opening and closing of the valve 63d is controlled by operational commands from the control unit 130. The circulation path 63a, upstream of the filter 63c, may be cooled by a known cooling means.

[0128] In the recovery / reuse unit 6 of this embodiment, a separation membrane section 27 may be provided midway along the waste liquid discharge pipe 23. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating the organic solvent from the waste liquid.

[0129] Furthermore, in the recovery and reuse unit 6 of this embodiment, a separation membrane section 27 may be provided midway along the separated liquid discharge pipe 28. In this case, the separation membrane section 27 may be provided, for example, upstream of the pump 28a. This allows an organic solvent with extremely high purity to be supplied to the multiple valve 13b.

[0130] [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 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 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 separating step onto the surface Wf of the substrate W. Note that 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.

[0131] The separation step is a step of separating and removing water from the effluent collected and stored in the effluent storage section 61 to obtain a separated liquid (organic solvent). When the valve 23c is opened in response to an operational command from the control section 130, the pump 23b is actuated, causing the effluent stored in the intermediate effluent storage section 22 to flow through the effluent discharge pipe 23 and be sent to the effluent storage section 61, where it is stored (storage step). When a predetermined amount of effluent has been stored in the effluent storage section 61, the control section 130 issues an operational command to the valve 23c to close the valve. Furthermore, in response to an operational command from the control section 130, the effluent cooling section 62 cools the effluent stored in the effluent storage section 61 (solid-liquid separation step, second cooling step). As described above, the cooling temperature of the effluent cooling section 62 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 effluent solidifies to form ice. This allows solid-liquid separation of the organic solvent and water to proceed in the wastewater.

[0132] In this embodiment, the effluent collected in the splash prevention cup 14 is not directly supplied to the effluent storage section 61, but is temporarily stored in the intermediate effluent storage section 22, so that the separation process can proceed stably even when the discharge of the effluent from the splash prevention cup 14 is delayed. Also, even when it takes time to generate ice by cooling the effluent using the effluent cooling section 62 (i.e., solid-liquid separation), it is possible to prevent the effluent from being excessively supplied to the effluent storage section 61.

[0133] Subsequently, after ice is generated, valve 63d is opened by an operation command from control unit 130, and pump 63b is operated to circulate the waste liquid containing ice through circulation path 63a (removal process). Because filter 63c, which enables ice removal, is provided midway through circulation path 63a, the ice in the waste liquid is removed by filter 63c, and only the separated liquid (organic solvent) returns to waste liquid reservoir 61. The concentration of the separated liquid (organic solvent) 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 63d by an operation command and stops pump 63b. 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 63a continues until the measured value of the organic solvent concentration by the concentration meter reaches the predetermined value. The organic solvent separated from the waste liquid in the separation step can be reused as a treatment liquid in the supply step, in the same manner as in the first embodiment.

[0134] As described above, in this embodiment, the organic solvent in the effluent can be separated and recovered by cooling the effluent to solidify the water and perform solid-liquid separation, and then removing the ice using filter 63c. 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.

[0135] (Sixth embodiment) A sixth embodiment of the present invention will be described below.

[0136] [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.

[0137] <Recycling unit> Next, the configuration of the recovery / reuse unit in the substrate processing apparatus 110 will be described below with reference to FIG. 10. FIG. 10 is an explanatory diagram schematically showing the substrate processing unit 1 and the recovery / reuse unit 7 in the substrate processing apparatus 100 of this embodiment. In FIG. 10, 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 2 of the first embodiment are assigned the same reference numerals, and detailed description thereof will be omitted.

[0138] 10, the recovery / reuse unit 7 of the present embodiment, like the recovery / reuse unit 2 of the first embodiment, recovers the processing liquid used to remove water remaining on the front surface Wf of the substrate W, and separates and removes the water from the recovered processing liquid to make it reusable. Specifically, the recovery / reuse unit 7 includes at least a separation section 70, as shown in FIG.

[0139] The separation unit 70 of this embodiment is characterized by including the first irradiation unit 25 of the first embodiment and the heat pipe 32 of the second embodiment. Specifically, the separation unit 70 includes at least a recovery pipe 21, a waste liquid storage unit 71, the first irradiation unit 25, the heat pipe 32 as a gas-liquid separation unit, a circulation path 26, a separation membrane unit 27, and a separated liquid discharge pipe 28.

[0140] As shown in FIG. 11 , the waste liquid storage unit 71 includes a storage tank 71a, an organic solvent recovery unit 31b for recovering the organic solvent, an exhaust pipe 71b provided at the top of the storage tank 71a, and a water discharge pipe 71c for discharging water separated from the waste liquid. FIG. 11 is an explanatory diagram schematically showing the waste liquid storage unit 71, the first irradiation unit 25, and the heat pipe 32. The storage tank 71a can store the waste liquid supplied from the splash prevention cup 14 via the recovery pipe 21. As described in the second embodiment, the organic solvent recovery unit 31b is provided above the liquid level of the waste liquid stored in the storage tank 71a and has an annular recovery unit 31c and an opening 31d. The annular recovery unit 31c is provided so as to extend in an annular shape from the inner wall of the storage tank 71a toward the center. The opening 31d is provided in the center of the annular recovery unit 31c and is formed by erecting an annular wall 31e in a direction approximately perpendicular to the annular recovery unit 31c. The provision of the annular wall 31e prevents the liquid organic solvent from flowing down into the wastewater stored in the storage tank 71a. Furthermore, the provision of the opening 31d in the center of the annular recovery unit 31c allows the vaporized organic solvent to rise to the annular cooling unit 32b. The exhaust pipe 71b can discharge water vapor generated by vaporization of water contained in the stored wastewater to the outside of the wastewater storage unit 71. The water discharge pipe 71c can discharge water separated from the wastewater by vaporizing the organic solvent from the storage tank 71a to the outside.

[0141] The connection position of the recovery pipe 21 in the storage tank 71a is located below the position where the organic solvent recovery unit 31b is provided. In addition, the storage tank 71a is connected to the circulation path 26 so that the organic solvent recovered from the wastewater and stored in the organic solvent recovery unit 31b is discharged to the circulation path 26, and the organic solvent circulated through the circulation path 26 returns to the organic solvent recovery unit 31b.

[0142] As described in the first embodiment, the first irradiator 25 irradiates the effluent stored in the effluent storage unit 71 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 irradiator 25 functions as a gas-liquid separator that vaporizes the water contained in the effluent and separates it from the organic solvent. For example, if the storage tank 71a is transparent to the first light, the first irradiator 25 can be disposed on the side of the storage tank 71a to irradiate the effluent stored in the storage tank 71a with the first light.

[0143] The position where the first irradiator 25 is disposed is not particularly limited as long as the first light can be irradiated onto the effluent stored in the storage tank 71a. For example, the first irradiator 25 may be disposed inside the storage tank 71a. In this way, even if the storage tank 71a is not transparent to the first light, the first light can be irradiated onto the effluent stored in the storage tank 71a.

[0144] In the recovery / reuse unit 7 of this embodiment, a separation membrane section 27 may be further provided midway along the recovery pipe 21. In this case, the separation membrane section 27 may be provided, for example, downstream of the valve 23c. This can further improve the efficiency of separating the organic solvent from the wastewater.

[0145] Furthermore, in the recovery and reuse unit 7 of this embodiment, a storage tank (not shown) for storing the separated liquid (organic solvent) may be provided midway along the circulation path 26. In this case, the storage tank is provided between the waste liquid storage section 71 and the pump 26a. By providing the storage tank, even when it takes time to separate a certain amount of organic solvent from the waste liquid into gas and liquid, the organic solvent can be stably circulated through the circulation path 26 or supplied to the multiple valve 13b.

[0146] [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 separating 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 containing at least the separated liquid (organic solvent) obtained in the separating process to the surface Wf of the substrate W. In this embodiment, the draining process is the same as in the second embodiment, and the supplying process is the same as in the first embodiment. Therefore, detailed explanations of these processes will be omitted.

[0147] The separation process is a process of separating and removing water from the waste liquid collected in the splash prevention cup 14 to obtain a separated liquid (organic solvent). When the valve 23c is opened in response to an operational command from the control unit 130, the pump 23b operates to supply the waste liquid, from which impurities have been removed by the filter 23a, to the storage tank 71a of the waste liquid storage unit 71, where the waste liquid is stored (storage process). Subsequently, when a predetermined amount of waste liquid has been stored in the storage tank 71a, the control unit 130 issues an operational command to close the valve 23c. Furthermore, in response to an operational command from the control unit 130, the first irradiation unit 25 irradiates the waste liquid stored in the storage tank 71a with a first light (gas-liquid separation process, first irradiation process). Because the wavelength range of the first light does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water, only the water contained in the waste liquid evaporates and becomes water vapor. This water vapor is exhausted from the exhaust pipe 71b.

[0148] Next, the separated liquid after being irradiated with the first light is heated using the heat pipe 32 (gas-liquid separation process, heating process). More specifically, the separated liquid stored in the storage tank 71a is heated by the heating section 32a of the heat pipe 32 to a temperature above the boiling point of the organic solvent and below the boiling point of water. This causes only the organic solvent to vaporize, and the vaporized organic solvent rises through the opening 31d of the organic solvent recovery section 31b. The vaporized organic solvent then comes into contact with the annular cooling section 32b and is cooled to a liquid state (gas-liquid separation process, first cooling process). The liquid organic solvent (separated liquid) does not fall into the drainage liquid but is collected in the annular recovery section 31c. The collected organic solvent is then supplied to the multiple valve 13b via the separated liquid discharge pipe 28 by the control section 130 issuing an operation command to open the flow rate adjustment valve 28b.

[0149] As described above, in this embodiment, the effluent is irradiated with first light that does not include the absorption wavelength band of the organic solvent but includes the absorption wavelength band of water, and then 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 to separate the water in the effluent into gas and liquid. 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 can reduce the amount of organic solvent waste.

[0150] (Other matters) The above description has been given of the most preferred embodiment of the present invention, but the present invention is not limited to this embodiment and various modifications are possible within the scope of the technical idea of ​​the present invention as set forth in the claims.

[0151] For example, in the recovery / reuse unit 2 according to the first embodiment, the effluent cooling unit 62 and the removal unit 63 according to the fifth embodiment may be combined to separate the organic solvent. Specifically, the effluent cooling unit 62 is provided in the storage tank 24a of the effluent storage unit 24, and the effluent stored in the storage tank 24a is cooled to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water. This causes ice to precipitate in the effluent, resulting in solid-liquid separation from the organic solvent. Furthermore, the removal unit 63 provided in the storage tank 24a circulates the effluent containing ice through the circulation path 63a, and only the ice is removed using the filter 63c. Next, the effluent from which the ice has been removed is returned to the storage tank 24a, and then the first irradiation unit 25 irradiates the effluent with first light to vaporize and separate the water contained in the effluent, leaving only the organic solvent stored in the storage tank 24a.

[0152] Furthermore, in the recovery / reuse unit 3 according to the second embodiment, the organic solvent can be separated by combining the effluent cooling section 62 and the removal section 63 according to the fifth embodiment. Specifically, the effluent cooling section 62 is provided in the storage tank 31a of the effluent storage section 31, and the effluent stored in the storage tank 31a is cooled to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water. This causes ice to precipitate in the effluent, resulting in solid-liquid separation from the organic solvent. Furthermore, the removal section 63 provided in the storage tank 24a circulates the effluent containing ice through the circulation path 63a, and only the ice is removed by the filter 63c. Subsequently, the effluent from which the ice has been removed is returned to the storage tank 24a and heated by the heat pipe 32 to vaporize and separate the water contained in the effluent, so that only the organic solvent is stored in the storage tank 31a.

[0153] Alternatively, the recovery / reuse unit 5 according to the fourth embodiment may be combined with the removal unit 63 according to the fifth embodiment to separate the organic solvent. In this case, the effluent cooling unit 54 first cools the effluent stored in the storage tank 31a of the effluent storage unit 31 to a temperature higher than the freezing point of the organic solvent but lower than the freezing point of water. This generates ice in the effluent, resulting in solid-liquid separation from the organic solvent. The removal unit 63 provided in the storage tank 24a then circulates the ice-containing effluent through the circulation path 63a, and the filter 63c removes only the ice. The effluent from which the ice has been removed is then returned to the storage tank 24a, and the second irradiation unit 52 irradiates the effluent with the second light to vaporize the organic solvent contained in the effluent. The vaporized organic solvent is then cooled in the circular cooling unit 53 to a liquid state, and then recovered by the organic solvent recovery unit 31b. [Explanation of symbols]

[0154] 1: substrate processing unit, 2 to 7: recovery and recycling unit, 13: supply section, 13b: multiple valve, 14: anti-scattering cup, 15: anti-scattering cup for SPM, 20: separation section, 21: recovery pipe, 22: intermediate waste liquid storage section, 23: waste liquid discharge pipe, 23a: filter, 24: waste liquid storage section, 24a: storage tank, 24b: exhaust pipe, 24c: rotation drive section, 24d: chamber, 25: first irradiation section, 26: circulation path, 26a: pump, 26b: filter, 26c: three-way valve, 27: separation membrane section, 27a: water discharge pipe, 28: separated liquid discharge pipe, 30: separation section, 31: waste liquid storage section, 31a: storage tank, 31b: organic solvent recovery section, 31c: annular recovery section, 31d: Opening, 31e: annular wall, 31f: water discharge pipe, 32: heat pipe, 32a: heating section, 32b: annular cooling section, 40: separation section, 41: SPM discharge section, 41a: SPM recovery pipe, 41b: heat exchange section, 41c: SPM discharge pipe, 50: separation section, 51: waste liquid storage section, 52: second irradiation section, 53: annular cooling section, 54: waste liquid cooling section, 60: separation section, 61: waste liquid storage section, 62: waste liquid cooling section, 63: removal section, 63a: circulation path, 63b: pump, 63c: filter, 70: separation section, 71: waste liquid storage section, 71a: storage tank, 71b: exhaust pipe, 71c: water discharge pipe, 100: substrate processing apparatus, 130: control section, 131: connection section, W: substrate, Wf: surface

Claims

1. A recovery and reuse unit that recovers and reuses wastewater discharged after substrate processing, a separation unit that recovers the waste liquid containing an organic solvent and water and separates the organic solvent or the water from the recovered waste liquid; The separation unit is a waste liquid storage section that stores the waste liquid discharged after the substrate processing; a gas-liquid separation unit that vaporizes either the organic solvent or the water in the effluent stored in the effluent storage unit to separate them from each other, and / or a solid-liquid separation unit that solidifies the water in the effluent stored in the effluent storage unit to separate it from the organic solvent; A recovery and reuse unit comprising:

2. The gas-liquid separation unit is 2. The recovery and reuse unit according to claim 1, further comprising: a first irradiation unit that irradiates the waste liquid stored in the waste liquid storage unit with first light that does not include an absorption wavelength band of the organic solvent but includes an absorption wavelength band of water, thereby vaporizing the water contained in the waste liquid.

3. The gas-liquid separation unit is a heating unit that heats the waste liquid stored in the waste liquid storage unit to a temperature that is equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water, thereby vaporizing the organic solvent; a first cooling unit that cools the vaporized organic solvent to generate the liquid organic solvent; Equipped with The recovery and reuse unit according to claim 1 , wherein the boiling point of the organic solvent is lower than the boiling point of the water.

4. The solid-liquid separation section a second cooling unit that cools the waste liquid stored in the waste liquid storage unit to a temperature that is higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice; The gas-liquid separation unit is a second irradiation unit that irradiates the effluent containing ice precipitated by cooling by the second cooling unit with second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent, thereby vaporizing the organic solvent contained in the effluent; a first cooling unit that cools the vaporized organic solvent to generate the liquid organic solvent; Equipped with The recovery and reuse unit of claim 1 , wherein the freezing point of the organic solvent is lower than the freezing point of the water.

5. The solid-liquid separation section a second cooling unit that cools the effluent stored in the effluent storage unit to a temperature that is higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice; a removal unit that removes the ice in the drained liquid; Equipped with The recovery and reuse unit of claim 1 , wherein the freezing point of the organic solvent is lower than the freezing point of the water.

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 or the water from the recovered waste liquid; The separation step comprises: a storing step of storing the wastewater discharged after the substrate processing; a gas-liquid separation step of vaporizing either the organic solvent or the water in the stored effluent to separate them from each other, and / or a solid-liquid separation step of solidifying the water in the stored effluent to separate it from the organic solvent; A substrate processing method comprising:

8. The gas-liquid separation step 8. The substrate processing method according to claim 7, further comprising: a first irradiation step of irradiating the stored waste liquid with first light that does not include an absorption wavelength band of the organic solvent but includes an absorption wavelength band of the water, thereby vaporizing the water contained in the waste liquid.

9. The gas-liquid separation step a heating step of heating the stored wastewater to a temperature equal to or higher than the boiling point of the organic solvent and lower than the boiling point of water to vaporize the organic solvent; a first cooling step of cooling the vaporized organic solvent to produce the organic solvent in a liquid state; Including, The substrate processing method according to claim 7 , wherein the boiling point of the organic solvent is lower than the boiling point of the water.

10. The solid-liquid separation step a second cooling step of cooling the stored wastewater to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice; The gas-liquid separation step a second irradiation step of irradiating the effluent containing the ice precipitated in the second cooling step with second light that does not include the absorption wavelength band of water but includes the absorption wavelength band of the organic solvent, thereby vaporizing the organic solvent contained in the effluent; a first cooling step of cooling the vaporized organic solvent to produce the organic solvent in a liquid state; Including, The substrate processing method according to claim 7 , wherein the freezing point of the organic solvent is lower than the freezing point of the water.

11. The solid-liquid separation step a second cooling step of cooling the stored wastewater to a temperature higher than the freezing point of the organic solvent and lower than the freezing point of water to precipitate ice; a removing step of removing the ice in the drained liquid; Including, The substrate processing method according to claim 7 , wherein the freezing point of the organic solvent is lower than the freezing point of the water.

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