Liquid processing apparatus, gas processing apparatus, substrate processing apparatus, and liquid processing method

Abstract

To provide a technology that can suppress the decrease in the removal rate of organic solvents by activated carbon. [Solution] The liquid treatment apparatus 8 comprises an acidic liquid mixing unit 82 and an organic solvent removal unit 83. The acidic liquid mixing unit 82 mixes an acidic liquid A containing an acidic component with a liquid to be treated L containing an organic solvent and an alkaline component. The organic solvent removal unit 83 passes the liquid to be treated L mixed with the acidic liquid A through an activated carbon 831 to remove the organic solvent from the liquid to be treated L.

Description

Technical Field

[0001] The present disclosure relates to a liquid processing apparatus, a gas processing apparatus, a substrate processing apparatus, and a liquid processing method.

Background Art

[0002] In a substrate processing apparatus used in a manufacturing process of a semiconductor device or the like, for example, a processing liquid (e.g., a chemical solution, a rinse liquid, an organic solvent, etc.) is supplied to a substrate to process the substrate (e.g., Patent Documents 1 and 2). In such a substrate processing apparatus, the processing liquid discharged from the substrate after being supplied to the substrate is recovered and discharged as processing waste liquid. Further, in such a substrate processing apparatus, while the processing liquid is being supplied to the substrate, the atmosphere of the processing liquid filled in the chamber is drawn out from the chamber and discharged as processing exhaust gas. Patent Document 1 describes that a cleaning liquid is supplied to the processing exhaust gas discharged from the chamber, and the component to be removed contained in the processing exhaust gas is dissolved in the cleaning liquid to remove it from the processing exhaust gas and purify the processing exhaust gas.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] For example, in a substrate processing apparatus, when a chemical solution and an organic solvent are used as a processing liquid, the processing waste liquid and the processing exhaust gas may contain a chemical solution component and an organic solvent. Further, the used cleaning liquid used for purifying such processing exhaust gas becomes a liquid containing a chemical solution component and an organic solvent.

[0005] When removing organic solvents from a liquid containing them, activated carbon is used, for example. That is, when a liquid containing organic solvents is passed through activated carbon, the organic solvents are adsorbed by the activated carbon and removed from the liquid. However, experiments by the present inventors have revealed that when liquids containing not only organic solvents but also chemical components, such as the wastewater from the above-mentioned treatment or used cleaning solutions, are passed through activated carbon, the removal rate of organic solvents by the activated carbon may decrease.

[0006] This disclosure aims to provide a technology that can suppress the decrease in the removal rate of organic solvents by activated carbon. [Means for solving the problem]

[0007] The first embodiment is a liquid treatment apparatus comprising: an acidic liquid mixing unit that mixes an acidic liquid containing an acidic component with a liquid to be treated that contains an organic solvent and an alkaline component; and an organic solvent removal unit that passes the liquid to be treated mixed with the acidic liquid through activated carbon to remove the organic solvent from the liquid to be treated.

[0008] A second embodiment is a liquid processing apparatus according to the first embodiment, comprising a control unit for adjusting the amount of acidic liquid mixed with the liquid to be treated in the acidic liquid mixing unit, wherein the control unit adjusts the amount of acidic liquid mixed with the liquid to be treated such that the pH of the liquid to be treated after mixing with the acidic liquid is 8 or less.

[0009] A third embodiment is a liquid processing apparatus according to the second embodiment, wherein the control unit adjusts the amount of the acidic solution mixed with the liquid to be processed such that the pH of the liquid to be processed after mixing with the acidic solution is 8 or less and 6 or more.

[0010] A fourth embodiment is a liquid processing apparatus according to the second or third embodiment, comprising a pH sensor for measuring the pH of the liquid to be processed, wherein the control unit adjusts the amount of the acidic liquid to be mixed with the liquid to be processed based on the measurement value obtained by the pH sensor.

[0011] The fifth aspect is a liquid processing apparatus according to any of the first to fourth aspects, wherein the acidic liquid is dilute sulfuric acid.

[0012] The sixth embodiment is a gas processing apparatus comprising a liquid processing apparatus according to any of the first to fifth embodiments, a gas chamber in which a flow path for the gas to be processed is formed, and a cleaning liquid supply unit that supplies a cleaning liquid to the gas to be processed flowing inside the gas chamber, wherein the liquid to be processed is the cleaning liquid supplied to the gas to be processed.

[0013] The seventh embodiment is a gas treatment apparatus according to the sixth embodiment, wherein the cleaning liquid supply unit is provided below the gas chamber and comprises a tank for storing the cleaning liquid, a nozzle disposed inside the gas chamber, a supply pipe for supplying the cleaning liquid stored in the tank to the nozzle, and a circulation pipe for circulating the cleaning liquid stored in the tank, and the liquid treatment apparatus is provided in the circulation pipe.

[0014] The eighth aspect is a substrate processing apparatus comprising a gas processing apparatus according to the sixth or seventh aspect, The apparatus comprises a processing chamber, a rotating holding unit that holds a substrate in a horizontal position inside the processing chamber and rotates the substrate around a vertical axis of rotation, and a processing liquid supply unit that supplies one or more processing liquids to the substrate held by the rotating holding unit, wherein the gas to be processed is the exhaust gas discharged from the processing chamber.

[0015] The ninth aspect is a substrate processing apparatus according to the eighth aspect, wherein the one or more processing liquids contain the organic solvent, and after the processing liquid supply unit supplies the organic solvent to the substrate, the substrate is dried by increasing the rotation speed of the rotating holding unit.

[0016] The tenth embodiment is a substrate processing apparatus comprising: a liquid processing apparatus according to any of the first to fifth embodiments; a processing chamber; a rotating holding unit that holds a substrate in a horizontal position inside the processing chamber and rotates the substrate around a vertical axis of rotation; and a processing liquid supply unit that supplies one or more processing liquids to the substrate held by the rotating holding unit, wherein the liquid to be processed is the processing liquid that has been supplied to the substrate and then recovered.

[0017] The eleventh embodiment is a substrate processing apparatus according to the tenth embodiment, wherein the one or more processing liquids contain the organic solvent, and after the processing liquid supply unit supplies the organic solvent to the substrate, the substrate is dried by increasing the rotation speed of the rotating holding unit.

[0018] A twelfth aspect is a liquid treatment method comprising: an acidic liquid mixing step of mixing an acidic liquid containing an acidic component with a liquid to be treated that contains an organic solvent and an alkaline component; and an organic solvent removal step of passing the liquid to be treated, which has been mixed with the acidic liquid, through activated carbon to remove the organic solvent from the liquid to be treated. [Effects of the Invention]

[0019] In each of the first to twelfth embodiments, an acidic solution is mixed with the liquid to be treated before it passes through activated carbon. When an acidic solution is mixed with the liquid to be treated, at least some of the alkaline components contained in the liquid are neutralized by the acidic components and converted into salts. As a result, the adsorption pores of the activated carbon are less likely to be depleted by the alkaline components, and the amount of organic solvent adsorbed is less likely to decrease. In other words, the decrease in the removal rate of organic solvents by activated carbon is suppressed.

[0020] In particular, according to the second embodiment, the concentration of alkaline components in the treated solution after mixing with the acidic solution is sufficiently reduced. As a result, the depletion of the adsorption pores of the activated carbon by the alkaline components is sufficiently suppressed. Consequently, a decrease in the removal rate of organic solvents is sufficiently suppressed.

[0021] In particular, according to the third aspect, both the concentration of the alkaline component and the concentration of the acidic component in the liquid to be treated after being mixed with the acidic liquid can be made sufficiently small.

[0022] In particular, according to the fourth aspect, since an amount of acidic liquid corresponding to the pH of the liquid to be treated is mixed into the liquid to be treated, the usage amount of the acidic liquid is optimized.

Brief Description of the Drawings

[0023] [Figure 1] FIG. 1 is a plan view schematically showing a substrate processing apparatus according to the first embodiment. [Figure 2] FIG. 2 is a side view schematically showing a part of the substrate processing apparatus. [Figure 3] FIG. 3 is a block diagram showing the configuration of the control unit. [Figure 4] FIG. 4 is a side view schematically showing a gas processing apparatus. [Figure 5] FIG. 5 is a side view schematically showing a liquid processing apparatus. [Figure 6] FIG. 6 is a diagram showing the flow of the process performed in the liquid processing apparatus. [Figure 7] FIG. 7 is a diagram showing the results of an experiment for evaluating the removal rate of an organic solvent by activated carbon. [Figure 8] FIG. 8 is a side view schematically showing a part of the substrate processing apparatus according to the second embodiment. [Figure 9] FIG. 9 is a diagram schematically showing the state where the process drainage discharged from a plurality of substrate processing apparatuses merges. [Figure 10] FIG. 10 is a side view schematically showing a gas processing apparatus according to a modification.

Modes for Carrying Out the Invention

[0024] The embodiments will be described below with reference to the attached drawings. Note that the components described in these embodiments are merely examples and are not intended to limit the scope of this disclosure to them alone. Furthermore, the drawings are schematic representations, and for the sake of clarity, some components may be omitted, dimensions may be exaggerated or simplified, numbers may be exaggerated or simplified, and components may be simplified as appropriate. Also, the positional relationships of the components shown in the drawings are not necessarily accurately represented.

[0025] Expressions indicating relative or absolute positional relationships (e.g., "in one direction," "along one direction," "parallel," "orthogonal," "center," "concentric," "coaxial," etc.) shall, unless otherwise specified, not only strictly represent the positional relationship but also include states that are relatively displaced with respect to angle or distance, within a tolerance or range that yields equivalent functionality. Expressions indicating equality (e.g., "identical," "equal," "homogeneous," etc.) shall, unless otherwise specified, not only represent states that are quantitatively exactly equal but also include states where there are differences that yield tolerance or equivalent functionality. Expressions indicating shape (e.g., "circular," "elliptical," "quadrilateral," "cylindrical," etc.) shall, unless otherwise specified, not only strictly represent the shape geometrically but also include shapes within a range that yields equivalent functionality, such as having irregularities or chamfers. Expressions such as "equipped," "possessing," "containing," and "having" a component are not exclusive expressions that exclude the existence of other components. The expression "at least one of A, B, and C" includes "A only," "B only," "C only," "any two of A, B, and C," and "all of A, B, and C." When ordinal numbers such as "first" or "second" are used, these terms are used for convenience to facilitate understanding of the embodiments and are not limited to the order that may result from these ordinal numbers.

[0026] <<First Embodiment>> <1. Substrate Processing Equipment> (a) Configuration The configuration of the substrate processing apparatus 100 according to the first embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic plan view showing the substrate processing apparatus 100. Figure 2 is a schematic side view showing a part of the substrate processing apparatus 100.

[0027] The substrate processing apparatus 100 comprises a load port 1, an indexer robot 2, a main transport robot 3, a processing unit 4, a gas-liquid separator 5, a gas processing apparatus 6, and a control unit 7.

[0028] (Load port 1) The load port 1 is an interface for loading and unloading substrates 9 into and from a storage container (e.g., carrier C) that houses multiple substrates 9. Multiple load ports 1 are provided, for example (three in the example shown in the figure). Multiple load ports 1 are arranged in a single row horizontally, for example. The carrier C may be a type that houses the substrates 9 in a sealed space (e.g., FOUP (Front Opening Unified Pod), SMIF (Standard Mechanical Interface) pod, etc.) or a type that exposes the substrates 9 to the outside air (e.g., OC (Open Cassette), etc.).

[0029] (Indexer Robot 2) The indexer robot 2 is a transport device that transports the substrate 9. For example, the indexer robot 2 is a horizontal articulated robot and is equipped with a pair of hands 21, 21 for holding the substrate 9 and arms 22 connected to each hand 21. The indexer robot 2 is also equipped with a drive mechanism (not shown) for rotating each hand 21 and bending, rotating, and raising and lowering each arm 22. The indexer robot 2 transports the substrate 9 between the carrier C placed on the load port 1 and the main transport robot 3. That is, the indexer robot 2 accesses the carrier C placed on the load port 1 and performs an unloading operation (i.e., the operation of taking out the substrate 9 contained in the carrier C with the hands 21) and an loading operation (i.e., the operation of placing the substrate 9 held by the hands 21 into the carrier C). The indexer robot 2 also accesses the transfer position and transfers the substrate 9 to and from the main transport robot 3.

[0030] (Main transport robot 3) The main transport robot 3 is a transport device that transports the substrate 9. For example, the main transport robot 3 is a horizontal articulated robot and is equipped with a pair of hands 31, 31 for holding the substrate 9 and arms 32 connected to each hand 31. The main transport robot 3 is also equipped with a drive mechanism (not shown) for rotating each hand 31 and bending, rotating, and raising and lowering each arm 32. The main transport robot 3 transports the substrate 9 between the indexer robot 2 and each processing unit 4. That is, the main transport robot 3 accesses the transfer position and transfers the substrate 9 to the indexer robot 2. The main transport robot 3 also accesses the processing unit 4 and performs loading operations (i.e., loading the substrate 9 held by the hands 31 into the processing unit 4) and unloading operations (i.e., unloading the substrate 9 from the processing unit 4 with the hands 31).

[0031] (Processing Unit 4) The processing unit 4 performs a predetermined process on the substrate 9 using a processing liquid. The processing unit 4 processes the substrate 9 one at a time (so-called single-wafer processing). Multiple processing units 4 may be provided in the substrate processing apparatus 100. As an example, multiple (for example, three) processing units 4 stacked vertically constitute one tower, and multiple such towers (four in the example shown in the figure) are provided surrounding the main transport robot 3.

[0032] The processing unit 4 includes, for example, a processing chamber 41, a spin chuck 42, a cup 43, and a processing liquid supply unit 44.

[0033] The processing chamber 41 is a housing that forms a processing space for the substrate 9 inside. The processing chamber 41 houses a spin chuck 42, a cup 43, and various nozzles (chemical nozzle 44a, rinse nozzle 44b, and organic solvent nozzle 44c) of the processing liquid supply unit 44. As an example, a fan filter unit 411 is provided on the ceiling of the processing chamber 41. The fan filter unit 411 sends air that has been purified by the filter downwards. This creates a flow of clean air (downflow) from top to bottom inside the processing chamber 41.

[0034] The spin chuck 42 holds the substrate 9 in a horizontal position (with the thickness direction aligned with the vertical direction) inside the processing chamber 41, and rotates the substrate 9 around the rotation axis J (rotation holding part). Specifically, the spin chuck 42 comprises, for example, a disc-shaped spin base 421, a holding part 422 above it that holds the substrate 9 in a horizontal position, and a drive mechanism 423 that rotates the spin base 421 around the rotation axis J. Here, for example, the rotation axis J is defined as an axis extending vertically through the center of the main surface of the spin base 421. In this configuration, with the holding part 422 holding the substrate 9 above the spin base 421, when the drive mechanism 423 rotates the spin base 421 around the rotation axis J, the substrate 9 rotates around the rotation axis J in a horizontal position.

[0035] The cup 43 is a cylindrical member and is positioned coaxially with the rotation axis J, surrounding the spin chuck 42. In the example shown, the cup 43 has a shape in which the upper part tapers in diameter towards the top. A receiving portion 43a is provided at the lower end of the cup 43. A lifting mechanism (not shown) is connected to the cup 43, and the cup 43 is moved up and down between a processing position (for example, a position where the upper edge of the cup 43 is positioned above the substrate 9 held above the spin base 421) and a retracted position (for example, a position where the upper edge of the cup 43 is positioned below the spin base 421) by this lifting mechanism.

[0036] Cup 43 receives and collects the processing liquid that is supplied to the substrate 9 held by the spin chuck 42 and then discharged (sprayed) from the substrate 9. Cup 43 is connected to a drainage line (not shown) through a first recovery pipe 431, and the processing liquid received and collected in cup 43 (hereinafter referred to as "processing drainage liquid Lp") is discharged from the processing chamber 41 through the first recovery pipe 431 and guided to the drainage line. Cup 43 also draws in the atmosphere of the processing liquid filling the processing chamber 41. Specifically, for example, a second recovery pipe 432 is connected to cup 43, and a fan (not shown) is provided there. The suction force formed by this fan draws the atmosphere of the processing liquid filling the processing chamber 41 into cup 43. Cup 43 is connected to the gas-liquid separator 5 through the second recovery pipe 432, and the atmosphere of the processed liquid drawn into cup 43 (hereinafter referred to as "processing exhaust Gp") is discharged from the processing chamber 41 through the second recovery pipe 432 and led to the gas-liquid separator 5.

[0037] The processing liquid supply unit 44 supplies one or more processing liquids (here, a chemical solution as the first processing liquid, a rinsing liquid as the second processing liquid, and an organic solvent as the third processing liquid) to the substrate 9 held by the spin chuck 42. Specifically, the processing liquid supply unit 44 includes, for example, a chemical solution nozzle 44a, a rinsing liquid nozzle 44b, and an organic solvent nozzle 44c.

[0038] The chemical nozzle 44a supplies the chemical solution to the substrate 9. Specifically, the chemical nozzle 44a supplies the chemical solution to the substrate 9 by discharging the chemical solution toward the upper surface of the substrate 9 held by the spin chuck 42. The chemical nozzle 44a is connected to the chemical supply source 443a via a chemical pipe 442a in which a chemical valve 441a is inserted. When the chemical valve 441a is opened, the chemical solution supplied from the chemical supply source 443a is supplied to the chemical nozzle 44a through the chemical pipe 442a and discharged from the chemical nozzle 44a. The chemical solution used here is a liquid containing an alkaline component. As an example, the chemical solution is SC-1 (ammonia hydrogen peroxide solution).

[0039] The rinse liquid nozzle 44b supplies rinse liquid to the substrate 9. Specifically, the rinse liquid nozzle 44b supplies rinse liquid to the substrate 9 by discharging the rinse liquid toward the upper surface of the substrate 9 held by the spin chuck 42. The rinse liquid nozzle 44b is connected to the rinse liquid supply source 443b via the rinse liquid piping 442b, which has a rinse liquid valve 441b inserted between them. When the rinse liquid valve 441b is opened, the rinse liquid supplied from the rinse liquid supply source 443b is supplied to the rinse liquid nozzle 44b through the rinse liquid piping 442b and discharged from the rinse liquid nozzle 44b. The rinse liquid used here is a liquid containing water. As an example, the rinse liquid is pure water (deionized water).

[0040] The organic solvent nozzle 44c supplies the organic solvent to the substrate 9. Specifically, the organic solvent nozzle 44c supplies the organic solvent to the substrate 9 by discharging the organic solvent toward the upper surface of the substrate 9 held by the spin chuck 42. The organic solvent nozzle 44c is connected to the organic solvent supply source 443c via the organic solvent piping 442c, which has an organic solvent valve 441c inserted between them. When the organic solvent valve 441c is opened, the organic solvent supplied from the organic solvent supply source 443c is supplied to the organic solvent nozzle 44c through the organic solvent piping 442c and discharged from the organic solvent nozzle 44c. The organic solvent used here is, for example, a water-soluble organic solvent. As an example, the organic solvent is isopropyl alcohol (IPA).

[0041] (Gas-liquid separator 5) The gas-liquid separator 5 separates the fluid flowing into it into a gaseous component and a liquid component. Specifically, the gas-liquid separator 5 comprises, for example, a gas-liquid separation box 51, a liquid pipe 52 connected to the gas-liquid separation box 51, and a gas pipe 53 connected to the gas-liquid separation box 51. The liquid pipe 52 is provided penetrating the bottom wall of the gas-liquid separation box 51 such that its end opening (liquid outlet) 520 is positioned slightly higher than the bottom wall of the gas-liquid separation box 51. On the other hand, the gas pipe 53 is provided penetrating the bottom wall of the gas-liquid separation box 51 such that its end opening (gas outlet) 530 is positioned higher than the liquid outlet 520. In this configuration, when a fluid containing gaseous and liquid components flows into the gas-liquid separation box 51, most of the liquid components contained in the fluid (for example, droplet-like or mist-like components) fall inside the gas-liquid separation box 51 and are stored there, and then flow into the liquid piping 52 through the liquid outlet 520. On the other hand, the gaseous components contained in the fluid that flows into the gas-liquid separation box 51 flow into the gas piping 53 through the gas outlet 530. This separates the gaseous and liquid components.

[0042] A second recovery pipe 432 is connected to the gas-liquid separation box 51. A liquid pipe 52 is connected to a drain line (not shown), and a gas pipe 53 is connected to the gas treatment device 6. Therefore, the exhaust gas Gp discharged from the treatment chamber 41 flows into the gas-liquid separation box 51. The exhaust gas Gp is ​​separated into gaseous and liquid components, with the liquid component being led to the drain line via the liquid pipe 52, and the gaseous component being led to the gas treatment device 6 via the gas pipe 53. In other words, the liquid component contained in the exhaust gas Gp is ​​largely removed in the gas-liquid separator 5 before it is led to the gas treatment device 6 via the gas pipe 53.

[0043] (Gas treatment device 6) The gas treatment device 6 removes components to be removed from the gas to be treated by supplying a cleaning solution to the gas to be treated. In this case, the exhaust gas Gp discharged from the treatment chamber 41 becomes the gas to be treated in the gas treatment device 6. The gas treatment device 6 will be described later.

[0044] (Control Unit 7) The control unit 7 controls the operation of each part of the substrate processing apparatus 100 (load port 1, indexer robot 2, main transport robot 3, processing unit 4 (specifically, spin chuck 42, cup 43 lifting mechanism, chemical valve 441a, rinse liquid valve 441b, organic solvent valve 441c, etc.), gas-liquid separator 5, gas processing apparatus 6, etc.). The control unit 7 is composed of, for example, a general-purpose computer with electrical circuits. As an example, as shown in Figure 3, the control unit 7 is composed of a CPU (Central Processor Unit) 71 that handles various calculation processes (data processing), a ROM (Read Only Memory) 72 that stores basic programs, etc., a RAM (Random Access Memory) 73 used as a work area when the CPU 71 performs predetermined processing (data processing), a storage device 74 (specifically, for example, a non-volatile storage device such as a flash memory or hard disk drive), a bus line 75 that connects these to each other, etc. A program P that defines the processing to be executed by the control unit 7 may be stored in the storage device 74 or RAM 73, etc. In this case, for example, the CPU 71 may execute program P, thereby controlling each part of the board processing apparatus 100 to the control unit 7, and the processing defined by program P may be executed in the board processing apparatus 100. That is, the CPU 71 may execute program P, and the circuit that performs the processing defined by program P may be realized in the control unit 7. However, some or all of the control performed by the control unit 7 (some or all of the circuit realized in the control unit 7) may be executed (realized) by hardware such as dedicated logic circuits. Furthermore, program P may be stored in a recording medium, and program P may be installed in the control unit 7 using this recording medium.

[0045] (b) Processing flow The series of processes performed in the substrate processing apparatus 100 will be explained further with reference to Figures 1 to 3. The series of processes performed in the substrate processing apparatus 100 proceed under the control of the control unit 7. That is, the control unit 7 controls each part of the substrate processing apparatus 100, thereby enabling the series of processes to proceed in the substrate processing apparatus 100.

[0046] First, the indexer robot 2 takes out the unprocessed substrate 9 contained in the carrier C placed on the load port 1, accesses the transfer position, and hands the substrate 9 to the main transport robot 3. When the main transport robot 3 receives the substrate 9 from the indexer robot 2, it carries the substrate 9 into the processing chamber 41 of the processing unit 4.

[0047] The substrate 9, once loaded into the processing chamber 41, is held by the spin chuck 42. Specifically, the substrate 9 is held horizontally above the spin base 421 by the holding unit 422. Once the substrate 9 is held by the spin chuck 42, the cup 43 moves from the retracted position to the processing position. Subsequently, the spin base 421 begins to rotate. This causes the substrate 9, held by the spin chuck 42, to begin rotating. Inside the processing chamber 41, a fan filter unit 411 constantly creates an airflow from top to bottom. The airflow that flows from top to bottom through the processing chamber 41 is drawn into the cup 43 by the suction force created by the fan provided in the second recovery pipe 432.

[0048] Next, the chemical valve 441a is opened. Then, the chemical (i.e., the chemical as the first processing liquid) supplied from the chemical supply source 443a is supplied to the chemical nozzle 44a through the chemical piping 442a and discharged from there. As a result, the chemical is supplied to the substrate 9 (i.e., the substrate 9 held and rotated by the spin chuck 42), and the substrate 9 is processed by the chemical. For example, if the chemical is SC-1, foreign matter such as particles is removed from the substrate 9 by the chemical. The chemical discharged (sprayed) from the rotating substrate 9 is received in the cup 43 and guided to the drain line through the first recovery pipe 431 as processed drainage liquid Lp. Meanwhile, the chemical atmosphere filling the processing chamber 41 is drawn into the cup 43 and flows into the gas-liquid separator 5 through the second recovery pipe 432 as processed exhaust gas Gp, where the liquid component is removed and then guided to the gas treatment device 6. After a predetermined time has elapsed since the dispensing of the chemical solution began, the chemical solution valve 441a is closed.

[0049] Next, the rinse liquid valve 441b is opened. Then, the rinse liquid supplied from the rinse liquid supply source 443b (i.e., the rinse liquid as the second treatment liquid) is supplied to the rinse liquid nozzle 44b through the rinse liquid piping 442b and discharged from there. As a result, the rinse liquid is supplied to the substrate 9 (i.e., the substrate 9 held and rotated by the spin chuck 42), and the chemical solution adhering to the substrate 9 is washed away (rinsed) by the rinse liquid. The chemical solution and rinse liquid discharged from the rotating substrate 9 are received in the cup 43 and led to the drain line through the first recovery pipe 431 as treatment wastewater Lp. Meanwhile, the atmosphere of chemical solution and rinse liquid filling the inside of the treatment chamber 41 is drawn into the cup 43 and flows into the gas-liquid separator 5 through the second recovery pipe 432 as treatment exhaust Gp, where the liquid component is removed and then led to the gas treatment device 6. After a predetermined time has elapsed since the start of the rinse fluid discharge, the rinse fluid valve 441b is closed.

[0050] Next, the organic solvent valve 441c is opened. Then, the organic solvent supplied from the organic solvent supply source 443c (i.e., the organic solvent as the third treatment liquid) is supplied to the organic solvent nozzle 44c through the organic solvent piping 442c and discharged from there. As a result, the organic solvent (in this case, IPA) is supplied to the substrate 9 (i.e., the substrate 9 held and rotated by the spin chuck 42), and the rinse liquid adhering to the substrate 9 is replaced with the organic solvent. The rinse liquid and organic solvent discharged from the rotating substrate 9 are received in the cup 43 and led to the drain line through the first recovery pipe 431 as treatment wastewater Lp. Meanwhile, the atmosphere of rinse liquid and organic solvent filling the inside of the treatment chamber 41 is drawn into the cup 43 and flows into the gas-liquid separator 5 through the second recovery pipe 432 as treatment exhaust Gp, where the liquid component is removed and then led to the gas treatment device 6. After a predetermined time has elapsed since the discharge of the organic solvent began, the organic solvent valve 441c is closed.

[0051] Next, the rotation speed of the spin base 421 is increased. As a result, the substrate 9 held in the spin chuck 42 rotates at high speed, and the organic solvent adhering to the substrate 9 is blown off by centrifugal force. This dries the substrate 9 (so-called spin drying). When the substrate 9 is rotated at high speed to blow off the adhering liquid, there is a risk that the patterns on the substrate 9 may collapse due to the surface tension of the adhering liquid. However, since the rinsing liquid adhering to the substrate 9 has been replaced in advance with an organic solvent that has lower surface tension, the collapse of the patterns is suppressed. The organic solvent discharged from the high-speed rotating substrate 9 is received in the cup 43 and guided to the drain line through the first recovery pipe 431 as processed wastewater Lp. Meanwhile, the atmosphere of organic solvent filling the inside of the processing chamber 41 is drawn into the cup 43 and flows into the gas-liquid separator 5 through the second recovery pipe 432 as processed exhaust gas Gp, where the liquid component is removed and then guided to the gas treatment device 6. When the substrate 9 is rotated at high speed for a predetermined time, the rotation of the spin base 421 stops. This stops the rotation of the substrate 9 held by the spin chuck 42. Subsequently, the spin chuck 42 releases its hold on the substrate 9, and the cup 43 moves from the processing position to the retracted position.

[0052] Next, the main transport robot 3 removes the processed substrate 9 from the processing chamber 41, accesses the transfer position, and hands the substrate 9 to the indexer robot 2. Upon receiving the substrate 9 from the main transport robot 3, the indexer robot 2 places the substrate 9 into the carrier C located on the load port 1. After the substrate 9 is removed from the processing chamber 41, a new substrate 9 is brought into the processing chamber 41, and the above series of processes is performed on this new substrate 9.

[0053] <2. Gas treatment equipment> (a) Configuration The configuration of the gas treatment device 6 will be explained with reference to Figure 4. Figure 4 is a schematic side view of the gas treatment device 6.

[0054] The gas treatment device 6 removes components to be removed from the gas to be treated G by supplying a cleaning solution Lw to the gas G (so-called scrubber). As described above, here, the exhaust gas Gp discharged from the treatment chamber 41 is led to the gas treatment device 6 via the gas-liquid separator 5 (Figure 2). In other words, the gas to be treated G in the gas treatment device 6 is the exhaust gas Gp discharged from the treatment chamber 41. As described above, in the treatment unit 4, a chemical solution, a rinsing solution, and an organic solvent are supplied to the substrate 9, so the exhaust gas Gp contains chemical solution components, rinsing solution components, and an organic solvent. In the gas treatment device 6, the organic solvent and chemical solution components are removed from the exhaust gas Gp by supplying a cleaning solution Lw to this exhaust gas Gp. In other words, the organic solvent and chemical solution components are the components to be removed.

[0055] The gas treatment device 6 includes, for example, a gas chamber 61, an inlet duct 62, an outlet duct 63, a fan 64, one or more (in this case, two) scrub filters 65a, 65b, one or more (in this case, two) mist filters 66a, 66b, a cleaning liquid supply unit 67, and a control unit 68.

[0056] (Gas Chamber 61) The gas chamber 61 is a housing that forms a flow path for the gas G to be treated. The gas chamber 61 is, for example, rectangular parallelepiped with an opening at its lower end. The opening at the lower end of the gas chamber 61 is connected to a first tank 671a and a second tank 671b (described later) so as to close it.

[0057] (Inlet duct 62) The inlet duct 62 is a duct for introducing the gas to be treated G into the gas chamber 61, and is provided on the side wall (first side wall) 61a of the gas chamber 61. Multiple inlet ducts 62 may be provided, and in this case, the multiple inlet ducts 62 may be arranged vertically. Here, the gas piping 53 of the gas-liquid separator 5 is connected to the inlet duct 62.

[0058] (Outlet duct 63) The outflow duct 63 is a duct for discharging the treated gas G, from which the target components have been removed, from inside the gas chamber 61, and is provided on the side wall (second side wall) 61b of the gas chamber 61 that faces the first side wall 61a.

[0059] (Fan 64) The fan 64 is installed, for example, inside the outlet duct 63 and forms a suction force. Specifically, for example, the fan 64 forms a suction force by sucking in air and blowing it out. The suction force formed by the fan 64 creates a flow (airflow) of the gas G to be treated. That is, the gas G to be treated flows into the gas chamber 61 via the inlet duct 62, flows through the inside of the gas chamber 61 from the side of the first side wall 61a to the side of the second side wall 61b, and flows out of the gas chamber 61 via the outlet duct 63.

[0060] However, in this case, three partitions (first partition 611, second partition 612, and third partition 613) are provided inside the gas chamber 61, thereby forming a meandering flow path inside the gas chamber 61. Specifically, the first partition 611 is positioned opposite the first side wall 61a, forming a first gas flow path V1 between them. The second partition 612 is positioned downstream of the first partition 611 and opposite it, forming a second gas flow path V2 between them. The third partition 613 is positioned downstream of the second partition 612 and opposite it, forming a third gas flow path V3 between them, and a fourth gas flow path V4 between them and the second side wall 61b. The first gas flow path V1, the second gas flow path V2, the third gas flow path V3, and the fourth gas flow path V4 are all connected to each other, forming a continuous meandering flow path. In other words, the first gas flow path V1 and the second gas flow path V2 are connected through a gap provided below the first partition 611, the second gas flow path V2 and the third gas flow path V3 are connected through a gap provided above the second partition 612, and the third gas flow path V3 and the fourth gas flow path V4 are connected through a gap provided below the third partition 613. Therefore, the gas to be treated G that flows into the gas chamber 61 from the inlet duct 62 flows downward through the first gas flow path V1 to the second gas flow path V2, flows upward through there to the third gas flow path V3, flows downward through there to the fourth gas flow path V4, flows upward through there to be discharged from the outlet duct 63.

[0061] (Scrub filters 65a, 65b) The scrub filters 65a and 65b are filters that allow gas and liquid to pass through. As will become clear later, the scrub filters 65a and 65b are wetted with a cleaning solution Lw. The gas to be treated G comes into contact with the cleaning solution Lw as it passes through the scrub filters 65a and 65b wetted with the cleaning solution Lw. The scrub filters 65a and 65b are installed in the middle of a meandering flow path formed inside the gas chamber 61. Specifically, for example, the first scrub filter (upstream scrub filter) 65a is installed in the second gas flow path V2, and the second scrub filter (downstream scrub filter) 65b is installed in the fourth gas flow path V4. Therefore, the gas to be treated G passes upward through the upstream scrub filter 65a in the second gas flow path V2 and upward through the downstream scrub filter 65b in the fourth gas flow path V4.

[0062] (Mist filters 66a, 66b) The mist filters 66a and 66b are filters that allow gas to pass through while capturing liquid. Therefore, when the gas to be treated G passes through the mist filters 66a and 66b, the liquid components contained in the gas to be treated G cannot pass through the mist filters 66a and 66b (they are captured by the mist filters 66a and 66b), and only the gaseous components contained in the gas to be treated G pass through the mist filters 66a and 66b. The mist filters 66a and 66b are installed in the middle of the meandering flow path formed inside the gas chamber 61. Specifically, for example, the first mist filter (upstream mist filter) 66a is installed so as to close a gap provided above the second partition 612. The second mist filter (downstream mist filter) 66b is installed above the second side wall 61b, interposed between it and the outflow duct 63 (that is, the outflow duct 63 is connected to the gas chamber 61 via the downstream mist filter 66b). Therefore, the gas G to be treated passes through the upstream mist filter 66a when it flows from the second gas flow path V2 to the third gas flow path V3, and passes through the downstream mist filter 66b when it flows out from the fourth gas flow path V4 to the outlet duct 63.

[0063] (Cleaning fluid supply unit 67) The cleaning liquid supply unit 67 supplies cleaning liquid Lw to the gas G to be treated flowing inside the gas chamber 61. As an example, here two cleaning liquid supply units 67a and 67b are provided. The first cleaning liquid supply unit 67a supplies cleaning liquid Lw to the gas G to be treated flowing through the first gas flow path V1 and the second gas flow path V2. The second cleaning liquid supply unit 67b supplies cleaning liquid Lw to the gas G to be treated flowing through the fourth gas flow path V4.

[0064] a. First cleaning fluid supply unit 67a The first cleaning fluid supply unit 67a comprises a first tank 671a, a first fresh fluid piping 672a, a first supply piping 673a, and a first circulation piping 674a.

[0065] The first tank 671a is a storage tank for storing the cleaning fluid Lw and is located below the gas chamber 61. Specifically, the first tank 671a has an open upper end and is connected to close the opening at the lower end of the upstream portion of the gas chamber 61 (at least the portion including the lower part of the first gas flow path V1 and the second gas flow path V2).

[0066] The first fresh liquid piping 672a is a piping that supplies unused cleaning liquid Lw to the first tank 671a. Specifically, the first fresh liquid piping 672a is connected at one end to a source of unused cleaning liquid Lw (fresh liquid supply source) 6721, and at the other end to the first tank 671a. The first fresh liquid piping 672a is provided with a first fresh liquid valve 6722a. When the first fresh liquid valve 6722a is opened, unused cleaning liquid Lw supplied from the fresh liquid supply source 6721 flows into the first tank 671a through the first fresh liquid piping 672a and is stored there. The cleaning liquid Lw used here is, for example, water (for example, industrial water).

[0067] The first supply pipe 673a is a pipe that supplies the cleaning liquid Lw stored in the first tank 671a to the first spray nozzles 6731a located in the first gas flow path V1 and the second gas flow path V2, respectively. The first supply pipe 673a is connected to the first tank 671a at one end and to the first spray nozzles 6731a at the other end. Specifically, the first supply pipe 673a comprises a first portion extending vertically upward from the end connected to the first tank 671a into the third gas flow path V3, a second portion extending horizontally above the upstream scrub filter 65a in the second gas flow path V2, and a third portion extending vertically downward in the first gas flow path V1. The first spray nozzles 6731a are attached to the second portion and the third portion, respectively. The first supply pipe 673a is also provided with a first liquid transfer pump 6732a. When the first liquid supply pump 6732a is activated, the cleaning liquid Lw stored in the first tank 671a is pumped up from the first tank 671a and supplied to each first spray nozzle 6731a through the first supply pipe 673a, from where it is discharged in a mist. The cleaning liquid Lw discharged from the first spray nozzle 6731a attached to the third section is supplied to the first gas flow path V1 (and consequently to the gas G to be treated that flows through it), and the cleaning liquid Lw discharged from the first spray nozzle 6731a attached to the second section is supplied to the upstream scrub filter 65a (and consequently to the gas G to be treated that passes through it).

[0068] The first circulation pipe 674a is a pipe that circulates the cleaning liquid Lw stored in the first tank 671a. Both ends of the first circulation pipe 674a are connected to the first tank 671a. The first circulation pipe 674a is equipped with a first circulation pump 6741a that pumps the cleaning liquid Lw stored in the first tank 671a at the pressure necessary for circulation (circulation pressure). When the first circulation pump 6741a is operated, the cleaning liquid Lw stored in the first tank 671a flows out of the first tank 671a, flows through the first circulation pipe 674a, and flows back into the first tank 671a (i.e., circulates through the first circulation pipe 674a). A liquid treatment device 8 is provided in the middle of the first circulation pipe 674a. The liquid treatment device 8 will be described later.

[0069] b. Second cleaning fluid supply unit 67b The second cleaning fluid supply unit 67b comprises a second tank 671b, a second fresh fluid piping 672b, a second supply piping 673b, and a second circulation piping 674b.

[0070] The second tank 671b is a storage tank for storing the cleaning fluid Lw and is located below the gas chamber 61. Specifically, the second tank 671b has an open upper end and is connected to close the opening at the lower end of the downstream portion of the gas chamber 61 (at least the portion including the lower side of the fourth gas flow path V4). As an example, the second tank 671b is located adjacent to the first tank 671a at a position that overlaps with the third gas flow path V3 when viewed from above.

[0071] The second fresh liquid pipe 672b is a pipe that supplies unused cleaning liquid Lw to the second tank 671b. Specifically, the second fresh liquid pipe 672b is connected to the fresh liquid supply source 6721 at one end and to the second tank 671b at the other end. The second fresh liquid pipe 672b is provided with a second fresh liquid valve 6722b. When the second fresh liquid valve 6722b is opened, unused cleaning liquid Lw supplied from the fresh liquid supply source 6721 flows into the second tank 671b through the second fresh liquid pipe 672b and is stored there. As described above, the cleaning liquid Lw used here is, for example, water.

[0072] The second supply pipe 673b is a pipe that supplies the cleaning liquid Lw stored in the second tank 671b to the second spray nozzle 6731b located in the fourth gas flow path V4. The second supply pipe 673b is connected to the second tank 671b at one end and to the second spray nozzle 6731b at the other end. Specifically, the second supply pipe 673b comprises a first portion that extends vertically upward outside the gas chamber 61 from the end connected to the second tank 671b, and a second portion that extends horizontally above the downstream scrub filter 65b in the fourth gas flow path V4, with the second spray nozzle 6731b attached to the second portion. A second liquid transfer pump 6732b is also provided in the second supply pipe 673b. When the second liquid supply pump 6732b is activated, the cleaning liquid Lw stored in the second tank 671b is pumped up from the second tank 671b and supplied to each second spray nozzle 6731b via the second supply pipe 673b, from where it is discharged in a mist. The cleaning liquid Lw discharged from the second spray nozzles 6731b attached to the second section is supplied to the downstream scrub filter 65b (and consequently, the gas G to be treated that passes through it).

[0073] The second circulation pipe 674b is a pipe that circulates the cleaning liquid Lw stored in the second tank 671b. Both ends of the second circulation pipe 674b are connected to the second tank 671b. The second circulation pipe 674b is equipped with a second circulation pump 6741b that pumps the cleaning liquid Lw stored in the second tank 671b at the pressure necessary for circulation (circulation pressure). When the second circulation pump 6741b is operated, the cleaning liquid Lw stored in the second tank 671b flows out of the second tank 671b, flows through the second circulation pipe 674b, and flows back into the second tank 671b (i.e., circulates through the second circulation pipe 674b). A liquid treatment device 8 is installed in the middle of the second circulation pipe 674b. The liquid treatment device 8 will be described later.

[0074] (Control Unit 68) The control unit 68 controls the operation of each component of the gas processing apparatus 6 (fan 64, first fresh liquid valve 6722a, second fresh liquid valve 6722b, first liquid transfer pump 6732a, second liquid transfer pump 6732b, first circulation pump 6741a, second circulation pump 6741b, etc.). The control unit 68 is configured, for example, by a general-purpose computer with electrical circuits. Some or all of the control performed by the control unit 68 may be implemented in the control unit 7 of the substrate processing apparatus 100 (Figure 3). In addition, the control unit 68 may control the operation of each component of the gas processing apparatus 6 in response to instructions from the control unit 7 of the substrate processing apparatus 100.

[0075] (b) Processing flow The processes performed in the gas processing device 6 will be explained further with reference to Figure 4. The series of processes performed in the gas processing device 6 proceed under the control of the control unit 68. That is, the control unit 68 controls each part of the gas processing device 6, thereby enabling the series of processes to proceed in the gas processing device 6.

[0076] First, the first fresh liquid valve 6722a and the second fresh liquid valve 6722b are opened. Then, unused cleaning liquid Lw supplied from the fresh liquid supply source 6721 flows into the first tank 671a through the first fresh liquid piping 672a and is stored there, and also flows into the second tank 671b through the second fresh liquid piping 672b and is stored there. After a predetermined amount of cleaning liquid Lw has been stored in each of the first tanks 671a and 671b, the first liquid transfer pump 6732a and the second liquid transfer pump 6732b are started at an appropriate timing. As a result, the cleaning liquid Lw stored in the first tank 671a is pumped up from the first tank 671a and supplied to each first spray nozzle 6731a through the first supply piping 673a, and is discharged in a mist from each first spray nozzle 6731a. Furthermore, the cleaning liquid Lw stored in the second tank 671b is pumped up from the second tank 671b and supplied to each second spray nozzle 6731b via the second supply pipe 673b, and is discharged in a mist from each second spray nozzle 6731b.

[0077] Next, the fan 64 is started. Then, the gas to be treated G (in this case, the exhaust gas Gp discharged from the treatment chamber 41) flows into the gas chamber 61 via the inlet duct 62. The gas to be treated G that has flowed into the gas chamber 61 flows sequentially through the first gas flow path V1, the second gas flow path V2, the third gas flow path V3, and the fourth gas flow path V4, and then flows out from inside the gas chamber 61 via the outlet duct 63. While the gas to be treated G flows sequentially through the first gas flow path V1, the second gas flow path V2, the third gas flow path V3, and the fourth gas flow path V4, the cleaning liquid Lw is supplied to the gas to be treated G, and the components to be removed (in this case, organic solvents and chemical components) are removed from the gas to be treated G.

[0078] In other words, in the first gas flow path V1, the gas to be treated G is supplied with cleaning liquid Lw discharged from the first spray nozzle 6731a. As a result, the components to be removed contained in the gas to be treated G dissolve in the cleaning liquid Lw and are removed from the gas to be treated G. The cleaning liquid Lw in which the components to be removed are dissolved (i.e., the cleaning liquid Lw containing the components to be removed) falls as droplets and is collected in the first tank 671a.

[0079] In the subsequent second gas flow path V2, the gas to be treated G passes through the upstream scrub filter 65a. The upstream scrub filter 65a is wetted by the cleaning liquid Lw discharged from the first spray nozzle 6731a. Therefore, the gas to be treated G comes into contact with the cleaning liquid Lw as it passes through the upstream scrub filter 65a. As a result, any remaining components to be removed in the gas to be treated G dissolve in the cleaning liquid Lw and are removed from the gas to be treated G. The cleaning liquid Lw containing the dissolved components falls as droplets and is collected in the first tank 671a.

[0080] When the gas to be treated G flows from the second gas channel V2 to the third gas channel V3, it passes through the upstream mist filter 66a. At this time, the liquid components contained in the gas to be treated G (i.e., the cleaning solution Lw in which the components to be removed are dissolved) cannot pass through the upstream mist filter 66a, and only the gaseous components contained in the gas to be treated G pass through the upstream mist filter 66a. The liquid components that could not pass through the upstream mist filter 66a fall as droplets and are collected in the first tank 671a.

[0081] In the subsequent fourth gas flow path V4, the gas to be treated G passes through the downstream scrub filter 65b. The downstream scrub filter 65b is wetted by the cleaning liquid Lw discharged from the second spray nozzle 6731b. Therefore, the gas to be treated G comes into contact with the cleaning liquid Lw as it passes through the downstream scrub filter 65b. As a result, any remaining components to be removed in the gas to be treated G dissolve in the cleaning liquid Lw and are removed from the gas to be treated G. The cleaning liquid Lw containing the dissolved components falls as droplets and is collected in the second tank 671b.

[0082] As the gas to be treated G flows from the fourth gas flow path V4 into the outlet duct 63, it passes through the downstream mist filter 66b. At this time, the liquid components contained in the gas to be treated G (i.e., the cleaning solution Lw in which the components to be removed are dissolved) cannot pass through the downstream mist filter 66b, and only the gaseous components contained in the gas to be treated G pass through the downstream mist filter 66b. The liquid components that could not pass through the downstream mist filter 66b fall as droplets and are collected in the second tank 671b.

[0083] The gas G to be treated, after passing through the downstream mist filter 66b, flows out of the gas chamber 61 via the outlet duct 63. The components to be removed have been sufficiently removed from the gas G to be treated after passing through the downstream mist filter 66b. In other words, at the stage when it flows out of the gas chamber 61, the gas G to be treated has become a harmless gas with a sufficiently low concentration of the components to be removed.

[0084] As described above, the cleaning solution Lw stored in the first tank 671a or the second tank 671b is discharged in a mist form inside the gas chamber 61 and supplied to the gas G to be treated flowing through it. After that, it falls as droplets and is received back into the original first tank 671a or second tank 671b. In other words, the cleaning solution Lw that was supplied to the gas G to be treated (used cleaning solution) returns to each of the first tank 671a and the second tank 671b. The used cleaning solution Lw contains the components to be removed that have been removed from the gas G to be treated. Therefore, as the used cleaning solution Lw returns, there is a risk that the concentration of the components to be removed in the cleaning solution Lw stored in each of the first tank 671a and the second tank 671b will increase. For example, if the cleaning solution Lw is supplied to the gas G to be treated at a flow rate of 2000 liters per hour for 3 hours, the concentration of the organic solvent (e.g., IPA) in the cleaning solution Lw stored in the first tank 671a (e.g., approximately 400 liters) may rise to about 2240 ppm, and the concentration of the chemical component (e.g., ammonium hydroxide (NH4OH) derived from SC-1) may rise to about 780 ppm. In addition, the concentration of IPA in the cleaning solution Lw stored in the second tank 671b (e.g., approximately 400 liters) may rise to about 390 ppm, and the concentration of ammonium hydroxide may rise to about 260 ppm.

[0085] However, here, while the cleaning liquid Lw is supplied to the gas to be treated G flowing through the gas chamber 61, the first circulation pump 6741a and the second circulation pump 6741b are operated so that the cleaning liquid Lw stored in the first tank 671a circulates through the first circulation pipe 674a, and the cleaning liquid Lw stored in the second tank 671b circulates through the second circulation pipe 674b. Here, a liquid treatment device 8 is provided in each of the first circulation pipe 674a and the second circulation pipe 674b (hereinafter, when the two are not distinguished, they will simply be referred to as "circulation pipe 674"). As will become clear later, in the liquid treatment device 8, the cleaning liquid Lw circulating in the circulation pipe 674 has its organic solvents removed, and the chemical components are changed into harmless components (salts) in conjunction with the removal of the organic solvents (detoxified). Therefore, an increase in the concentration of organic solvents and chemical components in the cleaning solution Lw stored in each of the first tank 671a and the second tank 671b (hereinafter, when the two are not distinguished, they will simply be referred to as "tank 671") is suppressed.

[0086] <3. Liquid treatment equipment> (a) Configuration The configuration of the liquid processing apparatus 8 will be explained with reference to Figure 5. Figure 5 is a schematic side view of the liquid processing apparatus 8.

[0087] The liquid treatment device 8 is installed in the piping (target piping) 80 through which the liquid to be treated (liquid to be treated) L flows, and removes (separates) organic solvents from the liquid to be treated L. As described above, in this case, the liquid treatment device 8 is installed in the circulation piping 674 connected to the tank 671. In this case, the target piping 80 is the circulation piping 674, and the liquid to be treated L is the cleaning liquid Lw stored in the tank 671. As described above, used cleaning liquid Lw supplied to the gas to be treated G returns to the tank 671, so the cleaning liquid Lw stored in the tank 671 contains the components to be removed (i.e., organic solvents and chemical components) removed from the gas to be treated G. For example, if the chemical is SC-1, the cleaning liquid Lw stored in the tank 671 contains ammonium hydroxide (NH4OH) derived from SC-1. In other words, the cleaning liquid Lw stored in the tank 671 contains organic solvents and alkaline components (specifically, it is an aqueous solution in which organic solvents and alkaline components are dissolved).

[0088] The liquid processing apparatus 8 includes a pH sensor 81, an acidic liquid mixing unit 82, an organic solvent removal unit 83, and a control unit 84.

[0089] (pH sensor 81) The pH sensor 81 is installed in the target piping 80 and measures the pH (hydrogen ion concentration) of the liquid to be treated L flowing through it. The pH sensor 81 is installed, for example, upstream of the acidic liquid mixing unit 82 (specifically, the mixing valve 823, which will be described later). As will be described later, in the acidic liquid mixing unit 82, acidic liquid A is mixed with the liquid to be treated L. If the pH sensor 81 is installed upstream of the acidic liquid mixing unit 82, the pH sensor 81 will measure the pH of the liquid to be treated L before acidic liquid A is mixed in. The measurement value acquired by the pH sensor 81 is input to the control unit 84.

[0090] (Acidic liquid mixing section 82) The acidic liquid mixing unit 82 mixes acidic liquid A with the liquid to be treated L. Specifically, the acidic liquid mixing unit 82 includes, for example, an acidic liquid supply source 821, an acidic liquid supply pipe 822, and a mixing valve 823.

[0091] The acidic solution supply source 821 is a source of acidic solution A. Here, "acidic solution A" is a solution containing an acidic component. For example, acidic solution A is dilute sulfuric acid, hydrochloric acid, or dilute hydrochloric acid. If the liquid to be treated L contains an alkaline component, when acidic solution A is mixed with the liquid to be treated L, at least a portion of the alkaline component is neutralized to form a salt. In other words, acidic solution A is a neutralizing solution that can neutralize the alkaline component contained in the liquid to be treated L.

[0092] The acidic liquid supply pipe 822 is a pipe that delivers acidic liquid A supplied from the acidic liquid supply source 821 to the target pipe 80. One end is connected to the acidic liquid supply source 821, and the other end is connected to a mixing valve 823 provided in the target pipe 80. A liquid transfer pump 822a is provided in the acidic liquid supply pipe 822. When the liquid transfer pump 822a is operated, acidic liquid A supplied from the acidic liquid supply source 821 flows into the mixing valve 823 through the acidic liquid supply pipe 822. A flow rate adjustment valve 822b is also provided in the acidic liquid supply pipe 822. The flow rate of acidic liquid A flowing into the mixing valve 823 through the acidic liquid supply pipe 822 (and consequently, the amount of acidic liquid A mixed with the liquid to be treated L) is determined by the opening degree of the flow rate adjustment valve 822b, and the opening degree of the flow rate adjustment valve 822b is adjusted (controlled) by the control unit 84.

[0093] The mixing valve 823 is formed, for example, using an in-line mixer. The mixing valve 823 is installed in the middle of the target piping 80 and mixes the liquid to be treated L flowing through the target piping 80 with the acidic liquid A flowing in from the acidic liquid supply piping 822 within the target piping 80. The mixing valve 823 is installed in the middle of the target piping 80, upstream of the organic solvent removal section 83. Therefore, the acidic liquid A is mixed with the liquid to be treated L before it flows into the organic solvent removal section 83.

[0094] (Organic solvent removal section 83) The organic solvent removal unit 83 removes organic solvents from the liquid to be treated L using activated carbon 831. That is, the organic solvent removal unit 83 removes organic solvents from the liquid to be treated L by passing the liquid to be treated L through the activated carbon 831 and adsorbing the organic solvents contained in the liquid to be treated L onto the activated carbon 831. However, as described above, the liquid to be treated L is mixed with acidic liquid A before flowing into the organic solvent removal unit 83. In other words, the organic solvent removal unit 83 removes organic solvents from the liquid to be treated L by passing the liquid to be treated L mixed with acidic liquid A through the activated carbon 831.

[0095] The organic solvent removal unit 83 specifically includes, for example, an activated carbon column (activated carbon tower) 830 in which activated carbon 831 is packed into a container 832. The activated carbon column 830 is inserted into the target piping 80. That is, the liquid to be treated L flowing through the target piping 80 flows into the container 832 through an inlet 832a provided on one end of the container 832, passes through the activated carbon 831 packed therein, flows out of the container 832 through an outlet 832b provided on the other end of the container 832, and flows back into the target piping 80. When the liquid to be treated L passes through the activated carbon 831 packed in the container 832, the organic solvent contained in the liquid to be treated L (organic solvent dissolved in the liquid to be treated L) is adsorbed by the activated carbon 831 and removed from the liquid to be treated L. However, the activated carbon 831 used here is pre-treated to make it easier for hydroxyl groups (-OH) to be adsorbed. In other words, the activated carbon 831 is pre-treated to increase the amount of adsorption of substances containing hydroxyl groups. Many organic solvents, including IPA, contain hydroxyl groups, and by applying such treatment to the activated carbon 831, organic solvents containing hydroxyl groups become more easily adsorbed onto the activated carbon 831 (i.e., they become easier to remove from the liquid L being treated).

[0096] (Control Unit 84) The control unit 84 controls the operation of each component of the liquid processing device 8 (pH sensor 81, liquid delivery pump 822a, flow rate adjustment valve 822b, etc.). The control unit 84 is configured, for example, by a general-purpose computer with electrical circuits. Some or all of the control performed by the control unit 84 may be implemented by the control unit 7 of the substrate processing device 100 or the control unit 68 of the gas processing device 6 (Figure 3). Alternatively, the control unit 68 may control the operation of each component of the liquid processing device 8 in response to instructions from the control unit 7 of the substrate processing device 100 or the control unit 68 of the gas processing device 6.

[0097] The control unit 84 adjusts the amount of acidic liquid A mixed with the liquid to be treated L in the acidic liquid mixing unit 82. Specifically, the control unit 84 adjusts the amount of acidic liquid A mixed with the liquid to be treated L so that the pH of the liquid to be treated L after mixing with acidic liquid A falls within an appropriate range. The appropriate pH range is, for example, 8 or less. Preferably, the appropriate pH range is 8 or less and 6 or more, and particularly preferably 7. Specifically, for example, the control unit 84 calculates the amount of acidic liquid A (appropriate mixing amount) necessary to bring the pH of the liquid to be treated L within an appropriate range based on the measurement value obtained by the pH sensor 81, and adjusts the opening of the flow rate adjustment valve 822b so that the calculated appropriate mixing amount of acidic liquid A flows into the mixing valve 823. As a result, the appropriate mixing amount of acidic liquid A is mixed with the liquid to be treated L in the mixing valve 823, and the pH of the liquid to be treated L flowing out downstream of the mixing valve 823 (i.e., the liquid to be treated L after mixing with acidic liquid A) falls within an appropriate range.

[0098] (b) Processing flow The processes performed in the liquid processing apparatus 8 will be explained with reference to Figure 5 and Figure 6. Figure 6 is a diagram showing the flow of processes performed in the liquid processing apparatus 8. The series of processes performed in the liquid processing apparatus 8 proceed under the control of the control unit 84. That is, the control unit 84 controls each part of the liquid processing apparatus 8, thereby enabling the series of processes to proceed in the liquid processing apparatus 8.

[0099] Step S1: Acid solution mixing process First, acidic solution A is mixed with the liquid to be treated L (in this case, the cleaning liquid Lw flowing through the circulation pipe 674) that flows through the target pipe 80. If the liquid to be treated L contains alkaline components, when acidic solution A is mixed with the liquid to be treated L, at least a portion of the alkaline components are neutralized and become salts. However, the amount of acidic solution A mixed with the liquid to be treated L is adjusted by the control unit 84. Specifically, when the liquid to be treated L begins to flow through the target pipe 80, the control unit 84 acquires the pH measurement value of the liquid to be treated L flowing through the target pipe 80 in real time from the pH sensor 81 (step S11). If the liquid to be treated L contains alkaline components, the pH measurement value will be greater than 7. Next, based on the measurement value acquired in step S11, the control unit 84 calculates the amount of acidic solution A necessary to bring the pH of the liquid to be treated L within the appropriate range (appropriate mixing amount) (step S12). As described above, the appropriate range for pH is, for example, 8 or less. Furthermore, the appropriate pH range is preferably 8 or less and 6 or more, and particularly preferably 7. Needless to say, the larger the measured value obtained in step S11, the larger the appropriate mixing amount. Next, the control unit 84 adjusts the opening of the flow rate adjustment valve 822b so that the appropriate mixing amount of acidic liquid A calculated in step S12 flows into the mixing valve 823 (step S13). As a result, the appropriate mixing amount of acidic liquid A is mixed with the liquid to be treated L in the mixing valve 823, and the pH of the liquid to be treated L flowing out to the downstream side of the mixing valve 823 is within the appropriate range. In other words, the concentration of alkaline components in the liquid to be treated L flowing out to the downstream side of the mixing valve 823 is sufficiently reduced.

[0100] Step S2: Organic solvent removal process Next, the organic solvent is removed from the liquid to be treated L, which has been mixed with the acidic liquid A. That is, the liquid to be treated L, which has been mixed with the acidic liquid A in the mixing valve 823, flows further through the target piping 80 and into the organic solvent removal section 83, where it passes through the activated carbon 831. As it passes through the activated carbon 831, the organic solvent contained in the liquid to be treated L is adsorbed onto the activated carbon 831 and removed (separated) from the liquid to be treated L.

[0101] (c) Removal rate of organic solvents The liquid treatment apparatus 8 functions effectively when the liquid to be treated L contains an organic solvent and an alkaline component. The reason for this is explained below.

[0102] Refer to Figure 7. Figure 7 shows the results of an experiment evaluating the removal rate of organic solvents by activated carbon 831. In this experiment, sample solutions were passed through activated carbon 831 at various SV values, and the IPA concentration of the sample solutions after passing through activated carbon 831 was measured. Figure 7(a) shows the measurement results when a first sample solution containing IPA but not ammonium hydroxide was used as the sample solution. However, the initial IPA concentration of the first sample solution (concentration before passing through activated carbon 831) was 3500 ppm. Figure 7(b) shows the measurement results when a second sample solution containing both IPA and ammonium hydroxide was used as the sample solution. However, the initial IPA concentration of the second sample solution was 1700 ppm, and the initial ammonium hydroxide concentration was 5250 ppm. In both sample solutions, the solvent was water. Furthermore, the activated carbon 831 through which the first and second sample solutions pass is the same, and this activated carbon 831 has been pre-treated to increase the amount of adsorption of substances containing hydroxyl groups.

[0103] For example, when the first sample solution was passed through activated carbon 831 with an SV value of "5", the IPA concentration decreased from the initial value of 3500 ppm to 50 ppm (IPA removal rate of approximately 98%). On the other hand, when the second sample solution was passed through activated carbon 831 with the same SV value of "5", the IPA concentration only decreased from the initial value of 1700 ppm to 400 ppm (IPA removal rate of approximately 75%).

[0104] The reason why the removal rate of IPA from the second sample solution was lower than that of the first sample solution is thought to be because the second sample solution contains ammonium hydroxide, an alkaline component. In other words, since alkaline components have hydroxyl groups, they are easily adsorbed by activated carbon 831 to the same extent as IPA. Therefore, when the second sample solution containing IPA and ammonium hydroxide was passed through activated carbon 831, the IPA and ammonium hydroxide competed for the adsorption pores of the activated carbon 831, resulting in a decrease in the amount of IPA adsorbed (and consequently, a decrease in the IPA removal rate).

[0105] According to the liquid treatment device 8, even if the liquid to be treated L contains an organic solvent and an alkaline component, the organic solvent can be efficiently removed from the liquid to be treated L. That is, in the liquid treatment device 8, the acidic solution A is mixed with the liquid to be treated L before it is passed through the activated carbon 831. When the acidic solution A is mixed with the liquid to be treated L, at least a portion of the alkaline component contained in the liquid to be treated L is neutralized by the acidic component and converted into a salt. For example, if the liquid to be treated L contains ammonium hydroxide and dilute sulfuric acid is used as the acidic solution A, the neutralization reaction changes ammonium hydroxide (NH4OH) to ammonium sulfate ((NH4)2SO4). Also, for example, if the liquid to be treated L contains ammonium hydroxide and hydrochloric acid or dilute hydrochloric acid is used as the acidic solution A, the neutralization reaction changes ammonium hydroxide to ammonium chloride (NH4Cl). Alkaline components, having hydroxyl groups, are easily adsorbed by activated carbon 831 to the same extent as IPA, whereas salts, lacking hydroxyl groups, are less easily adsorbed by activated carbon 831 than IPA. In other words, by mixing acidic solution A with the liquid to be treated L before passing it through activated carbon 831, the adsorption pores of activated carbon 831 are less likely to be taken over by alkaline components. Therefore, the amount of IPA adsorbed is less likely to decrease. That is, the reduction in the removal rate of IPA by activated carbon 831 is suppressed.

[0106] <4. Effects> The liquid treatment apparatus 8 according to the above embodiment includes an acidic liquid mixing unit 82 that mixes an acidic liquid A containing an acidic component with a liquid to be treated L containing an organic solvent and an alkaline component, and an organic solvent removal unit 83 that passes the liquid to be treated L mixed with the acidic liquid A through activated carbon 831 to remove the organic solvent from the liquid to be treated L. As described above, when the acidic liquid A is mixed with the liquid to be treated L, at least a portion of the alkaline component contained in the liquid to be treated L is neutralized by the acidic component and changed into a salt. Therefore, the adsorption pores of the activated carbon 831 are less likely to be taken away by the alkaline component, and the amount of organic solvent adsorbed is less likely to decrease. In other words, a decrease in the removal rate of organic solvent by the activated carbon 831 is suppressed.

[0107] In particular, the liquid treatment apparatus 8 according to the above embodiment includes a control unit 84 that adjusts the amount of acidic liquid A mixed with the liquid to be treated L in the acidic liquid mixing unit 82. The control unit 84 adjusts the amount of acidic liquid A mixed with the liquid to be treated L so that the pH of the liquid to be treated L after mixing with acidic liquid A is 8 or less. With this configuration, the concentration of alkaline components in the liquid to be treated L after mixing with acidic liquid A is sufficiently reduced. As a result, the depletion of the adsorption pores of the activated carbon 831 by alkaline components is sufficiently suppressed. Consequently, a decrease in the removal rate of organic solvents by the activated carbon 831 is sufficiently suppressed. Furthermore, a sufficient reduction in the concentration of alkaline components in the liquid to be treated L means that almost all of the alkaline components contained in the liquid to be treated L are converted into harmless components (salts). Consequently, the liquid to be treated L is sufficiently detoxified.

[0108] Furthermore, when the control unit 84 adjusts the amount of acidic solution A mixed into the treated liquid L so that the pH of the treated liquid L after mixing with acidic solution A is 8 or less and 6 or more, the treated liquid L after mixing with acidic solution A is brought closer to neutral. In other words, the concentrations of both the alkaline component and the acidic component in the treated liquid L after mixing with acidic solution A can be made sufficiently low.

[0109] Furthermore, the liquid processing apparatus 8 according to the above embodiment includes a pH sensor 81 for measuring the pH of the liquid to be processed L, and the control unit 84 adjusts the amount of acidic liquid A mixed into the liquid to be processed L based on the measurement value obtained by the pH sensor 81. With this configuration, the amount of acidic liquid A corresponding to the pH of the liquid to be processed L is mixed into the liquid to be processed L, so the amount of acidic liquid A used is optimized.

[0110] Furthermore, the liquid treatment apparatus 8 according to the above embodiment is provided in the gas treatment apparatus 6 (i.e., the gas treatment apparatus 6 comprises a gas chamber 61 in which a flow path for the gas to be treated G is formed, and a cleaning liquid supply unit 67 that supplies cleaning liquid Lw to the gas to be treated G flowing inside the gas chamber 61), and the cleaning liquid Lw supplied to the gas to be treated G in the gas treatment apparatus 6 is used as the liquid to be treated L. With this configuration, even if the cleaning liquid Lw supplied to the gas to be treated G contains an organic solvent and an alkaline component, the liquid treatment apparatus 8 can efficiently remove the organic solvent from the cleaning liquid Lw.

[0111] In particular, in the above embodiment, in the gas treatment apparatus 6 in which the liquid treatment apparatus 8 is provided, the cleaning liquid supply unit 67 is provided below the gas chamber 61 and includes a tank 671 for storing cleaning liquid Lw, nozzles (spray nozzles) 6731a, 6731b arranged inside the gas chamber 61, supply pipes 673a, 673b for supplying the cleaning liquid Lw stored in the tank 671 to the spray nozzles 6731a, 6731b, and circulation pipes 674 for circulating the cleaning liquid Lw stored in the tank 671. The liquid treatment apparatus 8 is provided in the circulation pipes 674. With this configuration, it is possible to suppress the increase in the concentration of organic solvents and chemical components in the cleaning liquid Lw stored in the tank 671, so that the cleaning liquid Lw stored in the tank 671 can be repeatedly supplied to the gas G to be treated. This reduces the amount of cleaning liquid Lw used.

[0112] Furthermore, in the above embodiment, the gas treatment apparatus 6, which is equipped with the liquid treatment apparatus 8, is provided in the substrate treatment apparatus 100 (i.e., the substrate treatment apparatus 100 comprises a treatment chamber 41, a rotating holding unit (spin chuck) 42 that holds the substrate 9 in a horizontal position inside the treatment chamber 41 and rotates the substrate 9 around a vertical rotation axis, and a treatment liquid supply unit 44 that supplies treatment liquid to the substrate 9 held by the spin chuck 42), and the treatment exhaust gas Gp discharged from the treatment chamber 41 in the substrate treatment apparatus 100 is used as the gas to be treated G. In this configuration, if the treatment exhaust gas Gp contains an organic solvent and an alkaline component, the cleaning liquid Lw supplied to it will also contain an organic solvent and an alkaline component. Even in such a case, the liquid treatment apparatus 8 can efficiently remove the organic solvent from the cleaning liquid Lw.

[0113] <<Second Embodiment>> The configuration of the substrate processing apparatus 200 according to the second embodiment will be described with reference to Figure 8. Figure 8 is a schematic side view showing a part of the substrate processing apparatus 200. In the following description, elements similar to those described in the above embodiment will be denoted by the same reference numerals, and their descriptions will be omitted.

[0114] In the substrate processing apparatus 200, a liquid processing apparatus 8 is provided in the first recovery pipe 431 connected to the cup 43 of the processing unit 4. In this liquid processing apparatus 8, the target piping 80 is the first recovery pipe 431, and the liquid to be processed L is the processing wastewater flowing through the first recovery pipe 431 (i.e., the processing liquid supplied to the substrate 9, discharged from the substrate 9, and collected by the cup 43) Lp (Figure 5).

[0115] As described above, in the processing unit 4, a chemical solution, a rinse solution, and an organic solvent are sequentially supplied to the substrate 9. Therefore, for example, when the processing wastewater Lp discharged at each stage is mixed, the processing wastewater Lp will contain chemical solution components, rinse solution components, and an organic solvent. Depending on the processing recipe, the chemical solution and the organic solvent may be supplied to the substrate 9 in parallel, or the chemical solution and the organic solvent may be pre-mixed and supplied to the substrate 9. In this case, the resulting processing wastewater Lp will contain chemical solution components and an organic solvent. In these cases, for example, if the chemical solution is SC-1, the processing wastewater Lp will contain ammonium hydroxide derived from SC-1. In other words, the processing wastewater Lp will contain an organic solvent and an alkaline component. As described above, the liquid processing device 8 can efficiently remove the organic solvent from the liquid to be processed L, even if the liquid to be processed L contains an organic solvent and an alkaline component. In other words, according to this embodiment, even if the treated wastewater Lp contains an organic solvent and an alkaline component, the liquid treatment apparatus 8 can efficiently remove the organic solvent from the treated wastewater Lp.

[0116] As schematically shown in Figure 9, generally, multiple substrate processing devices 200 are installed in a factory. In this case, of the wastewater generated in each substrate processing device 200, liquids containing organic solvents are discharged into an organic solvent drain (organic solvent drain) 201, and liquids that do not contain organic solvents are discharged into a water drain (water drain) 202. If a liquid processing device 8 is not installed in the first recovery pipe 431, it is highly likely that almost the entire amount of processing wastewater Lp generated in the substrate processing device 200 will be discharged into the organic solvent drain 201. If almost the entire amount of processing wastewater Lp generated in each of the multiple substrate processing devices 200 installed in the factory flows into the organic solvent drain 201, the amount of liquid flowing through it will be very large, and the burden on the process of removing the organic solvent from it will be very large. In contrast, if a liquid processing device 8 is installed in the first recovery pipe 431 of each substrate processing device 200, the processing wastewater Lp flowing into the first recovery pipe 431 will have the organic solvent removed in the liquid processing device 8. Therefore, the treated wastewater Lp can be discharged into the water drain 202 instead of the organic solvent drain 201. As a result, the amount of liquid flowing into the organic solvent drain 201 can be significantly reduced. Consequently, the burden of the process of removing the organic solvent from the liquid flowing through the organic solvent drain 201 can be significantly reduced.

[0117] Furthermore, in many cases, the liquid composition of the wastewater Lp generated in each of the multiple substrate processing apparatuses 200 (for example, the concentration of the organic solvent contained, the concentration of the chemical components contained, etc.) differs from one another. When a liquid processing apparatus 8 is provided individually for each of the multiple substrate processing apparatuses 200, a liquid processing apparatus 8 optimized for the liquid composition of the wastewater Lp generated in the substrate processing apparatus 200 can be provided. Specifically, for example, in a substrate processing apparatus 200 that generates wastewater Lp with a relatively high concentration of organic solvent, the amount of activated carbon 831 packed into the activated carbon column 830 in the liquid processing apparatus 8 provided therein can be made relatively large. This extends the time until the activated carbon 831 breaksthrough. Also, for example, in a substrate processing apparatus 200 that generates wastewater Lp with a relatively high concentration of alkaline components, the concentration of the acidic liquid A stored in the acidic liquid supply source 821 in the liquid processing apparatus 8 provided therein can be made relatively large. This suppresses an increase in the appropriate mixing amount.

[0118] <<Variation>> The configurations and operations of the liquid processing apparatus 8, gas processing apparatus 6, and substrate processing apparatus 100, 200 according to each of the above embodiments can be modified as appropriate.

[0119] In the gas treatment apparatus 6 according to the above embodiment, each of the multiple tanks 671 was provided with a circulation pipe 674 (and consequently, a liquid treatment apparatus 8), but the circulation pipe 674 (and consequently, the liquid treatment apparatus 8) may be shared among the multiple tanks 671. Figure 10 schematically shows a side view of the gas treatment apparatus 6a according to this modified example. Here, a shared circulation pipe 675 is provided between the first tank 671a and the second tank 671b. The shared circulation pipe 675 is a pipe that circulates the cleaning liquid Lw stored in each of the first tank 671a and the second tank 671b. Specifically, the shared circulation pipe 675 has, for example, a junction Q1 at one end, and its upstream side branches into a first branch section 675a ​​and a second branch section 675b. The first branch section 675a ​​is connected to the first tank 671a, and the second branch section 675b is connected to the second tank 671b. Furthermore, the shared circulation piping 675 has a diversion section Q2 at its other end, and its downstream side branches into a third branch section 675c and a fourth branch section 675d. The third branch section 675c is connected to the first tank 671a, and the fourth branch section 675d is connected to the second tank 671b. In addition, a shared circulation pump 6751 is provided downstream of the confluence section Q1 and upstream of the diversion section Q2 in the shared circulation piping 675. The shared circulation pump 6751 pumps the cleaning liquid Lw stored in the first tank 671a and the second tank 671b at the pressure necessary for circulation (circulation pressure). In addition, a liquid treatment device 8 is provided downstream of the confluence section Q1 and upstream of the diversion section Q2 in the shared circulation piping 675. In this liquid treatment apparatus 8, the target piping 80 is a shared circulation pipe 675, and the liquid to be treated L is the cleaning liquid Lw stored in the first tank 671a and the second tank 671b. In this configuration, when the shared circulation pump 6751 is operated, the cleaning liquid Lw stored in the first tank 671a and the second tank 671b circulate through the shared circulation pipe 675. Specifically, the cleaning liquid Lw stored in the first tank 671a flows out of the first tank 671a through the first branch section 675a, and the cleaning liquid Lw stored in the second tank 671b flows out of the second tank 671b through the second branch section 675b, and they merge at the confluence section Q1.The cleaning liquid Lw that flows from the confluence Q1 through the shared circulation pipe 675 to the branching section Q2 flows partly into the first tank 671a through the third branch section 675c, and the remainder flows into the second tank 671b through the fourth branch section 675d. The cleaning liquid Lw circulating in the shared circulation pipe 675 has its organic solvents removed in the liquid treatment device 8, and the chemical components are converted into harmless components (salts) in conjunction with the removal of the organic solvents. Therefore, an increase in the concentration of organic solvents and chemical components in the cleaning liquid Lw stored in the first tank 671a and the second tank 671b is suppressed.

[0120] In the above embodiment, the pH sensor 81 may be located downstream of the acidic liquid mixing unit 82. Alternatively, the pH sensor 81 may be omitted. If the pH sensor 81 is omitted, the amount of acidic liquid A mixed with the liquid to be treated L in the acidic liquid mixing unit 82 may be specified by the operator. That is, the control unit 84 may adjust the amount of acidic liquid A mixed with the liquid to be treated L (specifically, the opening degree of the flow rate adjustment valve 822b) according to the operator's specification.

[0121] In the liquid treatment apparatus 8 according to the above embodiment, a heating unit for heating the activated carbon 831 may be provided in the activated carbon column 830. When the heating unit heats the activated carbon 831, the organic solvent adsorbed on the activated carbon 831 is released. This restores the adsorption capacity of the activated carbon 831. When a heating unit is provided, it is preferable to provide a recovery pipe in the activated carbon column 830 and recover the organic solvent released from the activated carbon 831 by heating through the recovery pipe. Needless to say, the heating of the activated carbon 831 by the heating unit is performed when the flow of the liquid to be treated L in the target piping 80 is stopped.

[0122] In the gas treatment apparatus 6 according to the above embodiment, the cleaning liquid supply unit 67 included a first cleaning liquid supply unit 67a that supplies cleaning liquid Lw to the gas to be treated G flowing through the first gas passage V1 and the second gas passage V2, and a second cleaning liquid supply unit 67b that supplies cleaning liquid Lw to the gas to be treated G flowing through the fourth gas passage V4. However, such a configuration is not essential. For example, a single cleaning liquid supply unit may be configured to supply gas to the gas to be treated G flowing through the first gas passage V1, the second gas passage V2, and the fourth gas passage V4. In this case, the cleaning liquid supply unit may include, for example, a tank connected to completely close the opening at the lower end of the gas chamber 61, a new liquid piping connected to the tank to supply unused cleaning liquid Lw to it, a supply piping for supplying the cleaning liquid Lw stored in the tank to the first gas passage V1, the second gas passage V2, and the fourth gas passage V4, and a circulation piping for circulating the cleaning liquid Lw stored in the tank. In this case, a liquid treatment device 8 is provided in the circulation piping.

[0123] In the processing unit 4 according to the above embodiment, multiple types of chemical solutions may be supplied to the substrate 9 held in the spin chuck 42. Specifically, for example, a first chemical solution nozzle for supplying a first chemical solution containing an acidic component to the substrate 9 and a second chemical solution nozzle for supplying a second chemical solution containing an alkaline component to the substrate 9 may be provided, and the first chemical solution, rinse solution, second chemical solution, rinse solution, and organic solvent may be supplied to the substrate 9 in this order. In this case, the processing exhaust gas Gp contains an acidic component derived from the first chemical solution, an alkaline component derived from the second chemical solution, a rinse solution component, and an organic solvent. However, even in this case, the used cleaning solution Lw supplied to the processing exhaust gas Gp is ​​likely to be alkaline. In other words, the cleaning solution Lw stored in the tank 671 is likely to be a liquid containing an organic solvent and an alkaline component. Therefore, the liquid processing device 8 functions effectively.

[0124] In the above embodiment, the number of gas-liquid separators 5 provided in the substrate processing apparatus 100 may be multiple or one. For example, each processing unit 4 may be connected to an individual gas-liquid separator 5, or multiple processing units 4 may be connected to the same gas-liquid separator 5 (specifically, for example, the second recovery pipes 432 of multiple processing units 4 may merge and be connected to the gas-liquid separator 5 downstream of the merging point).

[0125] In the above embodiment, the number of gas processing devices 6 provided in the substrate processing device 100 may be one or more. For example, all of the processing units 4 provided in the substrate processing device 100 may be connected to the same gas processing device 6 (specifically, for example, the gas piping 53 of each gas-liquid separator 5 to which the processing units 4 are connected may be connected to the same gas processing device 6), or the processing units 4 provided in the substrate processing device 100 may be connected to different gas processing devices 6.

[0126] In the third embodiment, the number of liquid treatment devices 8 provided in the substrate processing apparatus 200 may be multiple or one. For example, each processing unit 4 may have its own individual liquid treatment device 8 in its first recovery pipe 431, or the first recovery pipes 431 of multiple processing units 4 (for example, multiple processing units 4 belonging to the same tower, or all processing units 4 mounted on the substrate processing apparatus 100) may merge, with the liquid treatment device 8 provided downstream of the merging point.

[0127] In the above embodiment, the chemical solution is not limited to SC-1. For example, the chemical solution may contain at least one of the following: aqueous ammonia, organic alkali (e.g., TMAH: tetramethylammonium hydroxide, etc.). Even when these chemical solutions are used, the treatment wastewater Lp and the washing liquid Lw after being supplied to the treatment exhaust gas Gp will be alkaline (they will be liquids containing alkaline components). Therefore, the liquid treatment device 8 will function effectively.

[0128] In the above embodiments, the rinsing solution is not limited to deionized water. For example, the rinsing solution may be any of the following: carbonated water, electrolyzed ionized water, hydrogen water, ozonated water, and hydrochloric acid water at a diluted concentration (e.g., about 10 to 100 ppm).

[0129] In the above embodiments, the organic solvent is not limited to IPA. For example, the organic solvent may be at least one of HFE (hydrofluoroether), methanol, ethanol, acetone, and trans-1,2-dichloroethylene. Furthermore, the organic solvent does not have to consist of only a single component, but may be a liquid mixture of multiple components. As described above, if the organic solvent is a substance having a hydroxyl group, the activated carbon 831 that has been pre-treated to increase the adsorption capacity of the substance having a hydroxyl group can effectively adsorb the organic solvent.

[0130] In the substrate processing apparatus 100 according to the above embodiment, the substrate 9 to be processed may be, for example, a semiconductor substrate. Alternatively, the substrate 9 to be processed may be, for example, a photomask glass substrate, a liquid crystal display glass substrate, a plasma display glass substrate, a Field Emission Display (FED) substrate, an optical disc substrate, a magnetic disc substrate, a magneto-optical disc substrate, and the like. Furthermore, the substrate 9 to be processed may be circular or rectangular. Moreover, the substrate 9 to be processed does not have to be a perfect circle or a perfect rectangle, and may have notches, orientation flats, and other shaped portions.

[0131] The liquid treatment apparatus 8 does not necessarily have to be installed in the gas treatment apparatus 6 or the substrate treatment apparatus 200, but may be installed in various other devices. Also, the gas treatment apparatus 6 on which the liquid treatment apparatus 8 is installed does not necessarily have to be installed in the substrate treatment apparatus 100, but may be installed in various other devices.

[0132] As described above, the liquid processing apparatus, gas processing apparatus, substrate processing apparatus, and liquid processing method have been described in detail. However, the above descriptions are illustrative in all respects and do not limit the processing liquid storage apparatus, substrate processing apparatus, and processing liquid supply method. It is understood that countless variations not illustrated can be envisioned without falling outside the scope of this disclosure. The components described in each of the above embodiments and each of the above variations can be combined or omitted as appropriate, as long as they do not contradict each other. [Explanation of Symbols]

[0133] 8. Liquid treatment equipment 81 pH sensor 82 Acidic liquid mixing section 821 Acidic liquid source 822 Acidic liquid supply piping 822b Flow control valve 823 Mixing valve 83 Organic Solvent Removal Section 830 Activated Carbon Column 831 Activated carbon 832 Container 84 Control Unit 6,6a Gas treatment device 61 Gas Chamber 62 Inlet duct 63 Outlet duct 64 Fans 65a, 65b Scrub Filter 66a, 66b Mist Filter 67 Cleaning fluid supply unit 671a Tank No. 1 674a 1st circulation piping 671b Tank No. 2 674b 2nd circulation piping 68 Control Unit 100,200 Substrate Processing Equipment 4 Processing Units 41 Processing Chamber 42 Spin Chuck 43 cups 44 Processing liquid supply unit

Claims

1. An acidic liquid mixing unit mixes an acidic liquid containing an acidic component with a treatment liquid containing an organic solvent and an alkaline component, An organic solvent removal unit that removes the organic solvent from the liquid to be treated by passing the liquid to be treated, which is mixed with the acidic solution, through activated carbon. A liquid processing apparatus equipped with the following features.

2. A liquid processing apparatus according to claim 1, A control unit in the acidic liquid mixing unit adjusts the amount of the acidic liquid mixed with the liquid to be treated. Equipped with, The control unit adjusts the amount of the acidic solution mixed into the liquid to be treated so that the pH of the liquid to be treated after mixing with the acidic solution becomes 8 or less. Liquid treatment equipment.

3. A liquid processing apparatus according to claim 2, The control unit adjusts the amount of the acidic solution mixed into the liquid to be treated so that the pH of the liquid to be treated after mixing with the acidic solution is 8 or less and 6 or more. Liquid treatment equipment.

4. A liquid processing apparatus according to claim 2 or 3, A pH sensor for measuring the pH of the liquid to be treated. Equipped with, The control unit adjusts the amount of the acidic solution mixed into the liquid to be treated based on the measurement value obtained by the pH sensor. Liquid treatment equipment.

5. A liquid processing apparatus according to any one of claims 1 to 3, The acidic solution is dilute sulfuric acid. Liquid treatment equipment.

6. A liquid processing apparatus according to any one of claims 1 to 3, A gas chamber in which a flow path for the gas to be processed is formed inside, A cleaning liquid supply unit that supplies cleaning liquid to the gas to be treated flowing inside the gas chamber, Equipped with, The liquid to be treated is the cleaning liquid supplied to the gas to be treated. Gas treatment device.

7. A gas processing apparatus according to claim 6, The aforementioned cleaning fluid supply unit A tank for storing the cleaning liquid is provided below the gas chamber, A nozzle positioned inside the gas chamber, A supply pipe for supplying the cleaning liquid stored in the tank to the nozzle, A circulation pipe for circulating the cleaning liquid stored in the tank, Equipped with, The liquid treatment device is provided in the circulation piping. Gas treatment device.

8. The gas treatment apparatus according to claim 6, Processing chamber and A rotating holding unit that holds the substrate in a horizontal position inside the processing chamber and rotates the substrate around a vertical axis of rotation, A processing liquid supply unit that supplies one or more processing liquids to the substrate held by the rotating holding unit, Equipped with, The gas to be treated is the exhaust gas discharged from the processing chamber. Circuit board processing equipment.

9. A substrate processing apparatus according to claim 8, The one or more processing solutions mentioned above contain the organic solvent, After the processing liquid supply unit supplies the organic solvent to the substrate, the rotation speed of the rotating holding unit is increased, thereby drying the substrate. Circuit board processing equipment.

10. A liquid processing apparatus according to any one of claims 1 to 3, Processing chamber and A rotating holding unit that holds the substrate in a horizontal position inside the processing chamber and rotates the substrate around a vertical axis of rotation, A processing liquid supply unit that supplies one or more processing liquids to the substrate held by the rotating holding unit, Equipped with, The liquid to be treated is the liquid that has been supplied to the substrate and then recovered. Circuit board processing equipment.

11. A substrate processing apparatus according to claim 10, The one or more processing solutions mentioned above contain the organic solvent, After the processing liquid supply unit supplies the organic solvent to the substrate, the rotation speed of the rotating holding unit is increased, thereby drying the substrate. Circuit board processing equipment.

12. An acidic solution mixing step is performed in which an acidic solution containing an acidic component is mixed with a treatment solution containing an organic solvent and an alkaline component, An organic solvent removal step is performed by passing the liquid to be treated, which is mixed with the acidic solution, through activated carbon to remove the organic solvent from the liquid to be treated. A liquid treatment method comprising:

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